Morphological changes during the life cycle of Aureobasidium pullulans (de Bary) Arnaud.

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Kocková-Kratochvílová, A; Cernáková, M; Sláviková, E

1980-01-01

Aureobasidium pullulans (de Bary) Arnaud was isolated from different natural materials plant blossoms in particular. Elements of vegetative multiplication, structure of colonies and cultures in liquid media were analyzed in detail, leading to construction of the life cycle of this organism. Morphological polymorphism was found to be combined with the production of melanin and the polysaccharide pullulan. Morphological analysis served for a directed selection for studies of physiological properties of this organism and its practical application.

Genome sequencing of four Aureobasidium pullulans varieties: biotechnological potential, stress tolerance, and description of new species

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Gostinčar, Cene; Ohm, Robin A; Kogej, Tina; Sonjak, Silva; Turk, Martina; Zajc, Janja; Zalar, Polona; Grube, Martin; Sun, Hui; Han, James; Sharma, Aditi; Chiniquy, Jennifer; Ngan, Chew Yee; Lipzen, Anna; Barry, Kerrie

2014-01-01

Background Aureobasidium pullulans is a black-yeast-like fungus used for production of the polysaccharide pullulan and the antimycotic aureobasidin A, and as a biocontrol agent in agriculture. It can cause opportunistic human infections, and it inhabits various extreme environments. To promote the understanding of these traits, we performed de-novo genome sequencing of the four varieties of A. pullulans. Results The 25.43-29.62 Mb genomes of these four varieties of A. pullulans encode between...

Two-dimensional NMR data of a water-soluble β-(1→3, 1→6-glucan from Aureobasidium pullulans and schizophyllan from Schizophyllum commune

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Hiroyuki Kono

2017-12-01

Full Text Available This article contains two-dimensional (2D NMR experimental data, obtained by the Bruker BioSpin 500 MHz NMR spectrometer (Germany which can used for the determination of primary structures of schizophyllan from Schizophyllum commune (SPG and a water-soluble β-(1→3, 1→6-glucan from Aureobasidium pullulans. Data include analyzed the 2D NMR spectra of these β-glucans, which are related to the subject of an article in Carbohydrate Polymers, entitled “NMR spectroscopic structural characterization of a water-soluble β-(1→3, 1→6-glucan from A. pullulans” (Kono et al., 2017 [1]. Data can help to assign the 1H and 13C chemical shifts of the structurally complex polysaccharides. Keywords: NMR, β-(1→3, 1→6-glucan, Aureobasidium pullulans, Schizophyllan, Spectral data

Discovering the role of the apolipoprotein gene and the genes in the putative pullulan biosynthesis pathway on the synthesis of pullulan, heavy oil and melanin in Aureobasidium pullulans.

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Guo, Jian; Huang, Siyao; Chen, Yefu; Guo, Xuewu; Xiao, Dongguang

2017-12-18

Pullulan produced by Aureobasidium pullulans presents various applications in food manufacturing and pharmaceutical industry. However, the pullulan biosynthesis mechanism remains unclear. This work proposed a pathway suggesting that heavy oil and melanin may correlate with pullulan production. The effects of overexpression or deletion of genes encoding apolipoprotein, UDPG-pyrophosphorylase, glucosyltransferase, and α-phosphoglucose mutase on the production of pullulan, heavy oil, and melanin were examined. Pullulan production increased by 16.93 and 8.52% with the overexpression of UDPG-pyrophosphorylase and apolipoprotein genes, respectively. Nevertheless, the overexpression or deletion of other genes exerted little effect on pullulan biosynthesis. Heavy oil production increased by 146.30, 64.81, and 33.33% with the overexpression of UDPG-pyrophosphorylase, α-phosphoglucose mutase, and apolipoprotein genes, respectively. Furthermore, the syntheses of pullulan, heavy oil, and melanin can compete with one another. This work may provide new guidance to improve the production of pullulan, heavy oil, and melanin through genetic approach.

Effects of melanin on the accumulation of exopolysaccharides by Aureobasidium pullulans grown on nitrate.

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Zheng, Weifa; Campbell, Bradley S; McDougall, Barbara M; Seviour, Robert J

2008-11-01

Aureobasidium pullulans produced pullulan and melanin when grown in medium containing low nitrate levels. With high nitrate concentrations, however, this fungus produced a mixture of exopolysaccharides (EPS) without melanin synthesis. At 0.78 g l(-1) N as nitrate, where no melanin synthesis occurred, maximum EPS yields reached 6.92 g l(-1) and then decreased to the final yield of 2.36 g l(-1). Following melanin addition (0.1 g l(-1)), yields reached 7.02 g l(-1) at 48 h and fell to a final yield of 5.21 g l(-1). The EPS produced in high nitrate medium contained both pullulan and (1-->3)-beta-glucan, but only pullulan was produced with melanin-supplementation. With melanin addition a doubling of (1-->3)-beta-glucanase activity was observed in high nitrate medium compared to that without supplementation. On the other hand amylolytic activities disappeared in medium with melanin production or addition. Culture filtrates sustained a higher reducing capacity (RC) when melanin was present. Low RC appeared to reduce (1-->3)-beta-glucanase activity and increase amylolytic activities. Thus, higher RC appears to inhibit production/activity of amylose-degrading enzymes capable of degrading pullulan, and stimulates (1-->3)-beta-glucanase synthesis/activity, leading to a preferential accumulation of pullulan.

[Complete genome sequencing of polymalic acid-producing strain Aureobasidium pullulans CCTCC M2012223].

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Wang, Yongkang; Song, Xiaodan; Li, Xiaorong; Yang, Sang-tian; Zou, Xiang

2017-01-04

To explore the genome sequence of Aureobasidium pullulans CCTCC M2012223, analyze the key genes related to the biosynthesis of important metabolites, and provide genetic background for metabolic engineering. Complete genome of A. pullulans CCTCC M2012223 was sequenced by Illumina HiSeq high throughput sequencing platform. Then, fragment assembly, gene prediction, functional annotation, and GO/COG cluster were analyzed in comparison with those of other five A. pullulans varieties. The complete genome sequence of A. pullulans CCTCC M2012223 was 30756831 bp with an average GC content of 47.49%, and 9452 genes were successfully predicted. Genome-wide analysis showed that A. pullulans CCTCC M2012223 had the biggest genome assembly size. Protein sequences involved in the pullulan and polymalic acid pathway were highly conservative in all of six A. pullulans varieties. Although both A. pullulans CCTCC M2012223 and A. pullulans var. melanogenum have a close affinity, some point mutation and inserts were occurred in protein sequences involved in melanin biosynthesis. Genome information of A. pullulans CCTCC M2012223 was annotated and genes involved in melanin, pullulan and polymalic acid pathway were compared, which would provide a theoretical basis for genetic modification of metabolic pathway in A. pullulans.

Genome sequencing of four Aureobasidium pullulans varieties: biotechnological potential, stress tolerance, and description of new species.

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Gostinčar, Cene; Ohm, Robin A; Kogej, Tina; Sonjak, Silva; Turk, Martina; Zajc, Janja; Zalar, Polona; Grube, Martin; Sun, Hui; Han, James; Sharma, Aditi; Chiniquy, Jennifer; Ngan, Chew Yee; Lipzen, Anna; Barry, Kerrie; Grigoriev, Igor V; Gunde-Cimerman, Nina

2014-07-01

Aureobasidium pullulans is a black-yeast-like fungus used for production of the polysaccharide pullulan and the antimycotic aureobasidin A, and as a biocontrol agent in agriculture. It can cause opportunistic human infections, and it inhabits various extreme environments. To promote the understanding of these traits, we performed de-novo genome sequencing of the four varieties of A. pullulans. The 25.43-29.62 Mb genomes of these four varieties of A. pullulans encode between 10266 and 11866 predicted proteins. Their genomes encode most of the enzyme families involved in degradation of plant material and many sugar transporters, and they have genes possibly associated with degradation of plastic and aromatic compounds. Proteins believed to be involved in the synthesis of pullulan and siderophores, but not of aureobasidin A, are predicted. Putative stress-tolerance genes include several aquaporins and aquaglyceroporins, large numbers of alkali-metal cation transporters, genes for the synthesis of compatible solutes and melanin, all of the components of the high-osmolarity glycerol pathway, and bacteriorhodopsin-like proteins. All of these genomes contain a homothallic mating-type locus. The differences between these four varieties of A. pullulans are large enough to justify their redefinition as separate species: A. pullulans, A. melanogenum, A. subglaciale and A. namibiae. The redundancy observed in several gene families can be linked to the nutritional versatility of these species and their particular stress tolerance. The availability of the genome sequences of the four Aureobasidium species should improve their biotechnological exploitation and promote our understanding of their stress-tolerance mechanisms, diverse lifestyles, and pathogenic potential.

Liamocin oil from Aureobasidium pullulans has antibacterial activity with specificity for species of Streptococcus

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Liamocin oil from Aureobasidium pullulans NRRL 50380 was tested for antibacterial activity. Liamocins inhibited growth of Streptococcus agalactiae, S. uberis, S. mitis, S. infantarius, and S. mutans, with minimum inhibitory concentrations from 20 'g/ml to 78 'g/ml. Enterococcus faecalis was less sus...

Antibacterial activity of liamocins oil from Aureobasidium pullulans is specific for species of Streptococcus

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Liamocins are a heterogeneous mixture of denser-than-water oils produced by the fungus Aureobasidium pullulans. Liamocins have unique chemical structures with a mannitol head group linked to long chain polyester tails consisting of multiple 3,5-dihydroxydecanoic acid ester groups, some of which are ...

Biological activities of organic extracts of four Aureobasidium pullulans varieties isolated from extreme marine and terrestrial habitats.

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Botić, Tanja; Kralj-Kunčič, Marjetka; Sepčić, Kristina; Batista, Urška; Zalar, Polona; Knez, Željko; Gunde-Cimerman, Nina

2014-01-01

We report on the screening for biological activities of organic extracts from seven strains that represent four varieties of the fungus Aureobasidium pullulans, that is A. pullulans var. melanogenum, A. pullulans var. pullulans, A. pullulans var. subglaciale and A. pullulans var. namibiae. We monitored haemolysis, cytotoxicity, antioxidant capacity and growth inhibition against three bacterial species. The haemolytic activity of A. pullulans var. pullulans EXF-150 strain was due to five different haemolytically active fractions. Extracts from all of the other varieties contained at least one haemolytically active fraction. Short-term exposure of cell lines to these haemolytically active organic extracts resulted in more than 95% cytotoxicity. Strong antioxidant capacity, corresponding to 163.88 μg ascorbic acid equivalent per gram of total solid, was measured in the organic extract of the strain EXF-3382, obtained from A. pullulans var. melanogenum, isolated from the deep sea. Organic extracts from selected varieties of A. pullulans exhibited weak antibacterial activities.

Production of pigment-free pullulan by swollen cell in Aureobasidium pullulans NG which cell differentiation was affected by pH and nutrition.

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Li, Bing-xue; Zhang, Ning; Peng, Qing; Yin, Tie; Guan, Fei-fei; Wang, Gui-li; Li, Ying

2009-08-01

A black yeast strain "NG" was isolated from strawberry fruit and identified as Aureobasidium pullulans. Strain NG displayed yeast-like cell (YL), swollen cell (SC), septate swollen cell (SSC), meristematic structure (MS), and chlamydospore (CH) morphologies. pH was the key factor regulating cell morphogenesis of strain NG. Differentiation of YL controlled by extracellular pH had no relationship with nutrition level. YL was maintained at pH >6.0, but was transformed into SC at pH approximately 4.5. SC, a stable cell type of A. pullulans, could bud, septate, or transform into MS or CH, in response to nutrition level and low pH. SC produced swollen cell blastospores (SCB) at pH 2.1 with abundant nutrition, and could transform into MS at lower pH (1.5). SC was induced to form CH by low level nutrition and pH melanin) were produced by SC of strain NG. Pullulan content of the polysaccharides was very high (98.37%). Fourier-transform infrared spectroscopy confirmed that chemical structures of the polysaccharides and standard pullulan were identical. Swollen cells produced 2.08 mg/ml non-pigmented polysaccharides at 96 h in YPD medium. Controlling pH of fermentation is an effective and convenient method to harvest SC for melanin-free pullulan production.

Production of anti-streptococcal liamocins from agricultural biomass by Aureobasidium pullulans.

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Leathers, Timothy D; Price, Neil P J; Manitchotpisit, Pennapa; Bischoff, Kenneth M

2016-12-01

Liamocins are unique heavier-than-water "oils" produced by certain strains of the fungus Aureobasidium pullulans. Liamocins have antibacterial activity with specificity for Streptococcus sp. Previous studies reported that liamocin yields were highest from strains of A. pullulans belonging to phylogenetic clades 8, 9, and 11, cultured on medium containing sucrose. In this study, 27 strains from these clades were examined for the first time for production of liamocins from agricultural biomass substrates. Liamocin yields were highest from strains in phylogenetic clade 11, and yields were higher from cultures grown on sucrose than from those grown on pretreated wheat straw. However, when supplementary enzymes (cellulase, β-glucosidase, and xylanase) were added, liamocin production on pretreated wheat straw was equivalent to that on sucrose. Liamocins produced from wheat straw were free of the melanin contamination common in sucrose-grown cultures. Furthermore, MALDI-TOF MS analysis showed that liamocins produced from wheat straw were under-acetylated, resulting in higher proportions of the mannitol A1 and B1 species of liamocin, the latter of which has the highest biological activity against Streptococcus sp.

Aureobasidium pullulans infection in a patient with chronic lymphocytic leukemia

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Leonardo Rodrigues de Oliveira

2013-09-01

Full Text Available Saprophytic fungi are being increasingly recognized as etiologic agents of mycoses in immunosuppressed patients. We report a case of subcutaneous infiltration by Aureobasidium pullulans, likely due to traumatic inoculation, in a neutropenic patient during chemotherapy for chronic lymphocytic leukemia. The patient was treated with amphotericin B deoxycholate but was subsequently switched to itraconazole, which improved the lesion. This case highlights the importance of considering unusual fungal infections in critically ill patients such as those who are immunosuppressed due to chemotherapy. Diagnostic techniques and effective antifungal therapy have improved the prognosis of these cases.

Strain improvement and statistical optimization as a combined strategy for improving fructosyltransferase production by Aureobasidium pullulans NAC8

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Adedeji Nelson Ademakinwa

2017-12-01

A relatively low FTase-producing strain of Aureobasidium pullulans NAC8 was enhanced for optimum production using a two-pronged approach involving mutagenesis and statistical optimization. The improved mutant strain also had remarkable biotechnological properties that make it a suitable alternative than the wild-type.

[Amylase production by Aureobasidium pullulans in liquid and solid media].

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Lodato, P B; Forchiassin, F; Segovia de Huergo, M B

1997-01-01

Amylase production by a strain of Aureobasidium pullulans isolated in the laboratory was evaluated in liquid media (complex and synthetic) and in solid medium (wheat bran). There was an inhibitory effect in amylase production or amylase secretion by glucose. Asparagine was the best nitrogen source for amylase production (4-6 g/l). Only chlamidospores and melanin but not, amylase activity, were obtained with ammonium sulfate. Amylase production in solid culture was higher than the production obtained in the liquid media assayed. Optimum initial moisture content in solid culture ranged between 57 and 74%. No difference was observed in amylase production between solid media inoculated with cells grown in liquid or solid media.

Direct production of feruloyl oligosaccharides and hemicellulase inducement and distribution in a newly isolated Aureobasidium pullulans strain.

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Yu, Xiao-hong; Gu, Zhen-xin

2014-02-01

Studies were carried out to screen and identify strains that are able to directly produce ferulic oligosaccharides (FOs) from wheat bran (WB). The inducement and distribution of hemicellulases from strain 2012, which was identified as a non-melanin secreting strain of Aureobasidium pullulans (A. pullulans), were also determined. In a 60 g/L WB solution, A. pullulans could produce 545 nmol/L FOs, 64.12 IU/mL xylanase and 0.14 IU/mL ferulic acid esterase (FAE). A. pullulans was cultivated in media with WB, glucose, xylose, sucrose, lactose or xylan as the carbon source, and hemicellulases were mainly induced by xylan and WB and inhibited by glucose and sucrose. Xylanase and FAE were mainly present in the culture filtrate, xylosidase in the hyphal filaments and arabinofuranosidase was a membrane-bound enzyme. The yield of FOs was positively correlated to the hemicellulases activity, and significantly positively (P < 0.05) correlated to the xylanase activity (r = 0.992).

Development of a one-step gene knock-out and knock-in method for metabolic engineering of Aureobasidium pullulans.

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Guo, Jian; Wang, Yuanhua; Li, Baozhong; Huang, Siyao; Chen, Yefu; Guo, Xuewu; Xiao, Dongguang

2017-06-10

Aureobasidium pullulans is an increasingly attractive host for bio-production of pullulan, heavy oil, polymalic acid, and a large spectrum of extracellular enzymes. To date, genetic manipulation of A. pullulans mainly relies on time-consuming conventional restriction enzyme digestion and ligation methods. In this study, we present a one-step homologous recombination-based method for rapid genetic manipulation in A. pullulans. Overlaps measuring >40bp length and 10μg DNA segments for homologous recombination provided maximum benefits to transformation of A. pullulans. This optimized method was successfully applied to PKSIII gene (encodes polyketide synthase) knock-out and gltP gene (encodes glycolipid transfer protein) knock-in. After disruption of PKSIII gene, secretion of melanin decreased slightly. The melanin purified from disruptant showed lower reducing capacity compared with that of the parent strain, leading to a decrease in exopolysaccharide production. Knock-in of gltP gene resulted in at least 4.68-fold increase in heavy oil production depending on the carbon source used, indicating that gltP can regulate heavy oil synthesis in A. pullulans. Copyright © 2017 Elsevier B.V. All rights reserved.

Heterologous expression of Spathaspora passalidarum xylose reductase and xylitol dehydrogenase genes improved xylose fermentation ability of Aureobasidium pullulans.

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Guo, Jian; Huang, Siyao; Chen, Yefu; Guo, Xuewu; Xiao, Dongguang

2018-04-30

Aureobasidium pullulans is a yeast-like fungus that can ferment xylose to generate high-value-added products, such as pullulan, heavy oil, and melanin. The combinatorial expression of two xylose reductase (XR) genes and two xylitol dehydrogenase (XDH) genes from Spathaspora passalidarum and the heterologous expression of the Piromyces sp. xylose isomerase (XI) gene were induced in A. pullulans to increase the consumption capability of A. pullulans on xylose. The overexpression of XYL1.2 (encoding XR) and XYL2.2 (encoding XDH) was the most beneficial for xylose utilization, resulting in a 17.76% increase in consumed xylose compared with the parent strain, whereas the introduction of the Piromyces sp. XI pathway failed to enhance xylose utilization efficiency. Mutants with superior xylose fermentation performance exhibited increased intracellular reducing equivalents. The fermentation performance of all recombinant strains was not affected when glucose or sucrose was utilized as the carbon source. The strain with overexpression of XYL1.2 and XYL2.2 exhibited excellent fermentation performance with mimicked hydrolysate, and pullulan production increased by 97.72% compared with that of the parent strain. The present work indicates that the P4 mutant (using the XR/XDH pathway) with overexpressed XYL1.2 and XYL2.2 exhibited the best xylose fermentation performance. The P4 strain showed the highest intracellular reducing equivalents and XR and XDH activity, with consequently improved pullulan productivity and reduced melanin production. This valuable development in aerobic fermentation by the P4 strain may provide guidance for the biotransformation of xylose to high-value products by A. pullulans through genetic approach.

Purification, Characterization of Amylase from Indigenously Isolated Aureobasidium pullulans Cau 19 and Its Bioconjugates with Gold Nanoparticles.

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Mulay, Y R; Deopurkar, R L

2018-02-01

The amylase from Aureobasidium pullulans Cau 19 was purified by ammonium sulfate precipitation and Sephadex G-100 chromatography with a 9.25-fold increase in specific activity as compared to crude enzyme. Km and turn over values of the enzyme were 6.25 mg/mL and 5.0 × 10 2 /min, respectively. Effect of different metal ions on the purified enzyme was investigated; 1 mM calcium (Ca) and cobalt (Co) enhanced enzyme activity by twofold; copper (Cu) had no effect on the activity of the enzyme. Mercury (Hg) 1 mM caused 90% inactivation whereas iron (Fe) and manganese (Mn) caused 10 to 16% inhibition. Amylase from A. pullulans Cau 19 was bioconjugated to gold nanoparticles synthesized using the biomass of A. pullulans Cau 19. Fourier transform infrared spectroscopy confirmed the conjugation of the enzyme to the gold nanoparticles. Though, only 20% of the added enzyme was adsorbed/conjugated on gold nanoparticles, 80% of the adsorbed activity could be estimated in the assay. The conjugated enzyme exhibited better tolerance to a broad pH range of 3.0-9.0 and higher temperatures compared with native enzyme.

Aureobasidium pullulans Fermented Feruloyl Oligosaccharide: Optimization of Production, Preliminary Characterization, and Antioxidant Activity

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Xiaohong Yu

2013-11-01

Full Text Available Wheat bran (WB was subjected to processing with Aureobasidium pullulans (A. pullulans under selected conditions to partially break down the xylan into soluble products (mainly feruloyl oligosaccharides, FOs. The objective of this study was to investigate the technology for one-step fermentation of WB by A. pullulans without melanin secretion to produce FOs as well as to determine their structural features and antioxidant activity. Initial pH, inoculation quantity, and fermentation temperature were found to be efficient for releasing FOs according to the Plackett-Burman design (PBD. Based on the D-Optimal design, a yield of 904 nmol of FOs / L of fermentation broth was obtained under optimal conditions of initial pH 6.0, inoculation quantity 4.50%, and fermentation temperature 29 oC. Purification of FOs was performed with alcohol precipitation and Amberlite XAD-2. GC, IR, and ESI-MS demonstrated that FOs consist of feruloyl arabinosyl xylopentose (FAX5, Mw986, feruloyl arabinosyl xylotetraose (FAX4, Mw854, feruloyl arabinosyl xylotriose (FAX3, Mw722, and feruloyl arabinosyl xylobiose (FAX2, Mw590. Increasing the FO dose led to increased activity of SOD and GSH-Px in serum of S180 tumor-bearing mice, while the level of MDA was reduced, thus improving its in vivo antioxidant activity.

Plasticizers increase adhesion of the deteriogenic fungus Aureobasidium pullulans to polyvinyl chloride.

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Webb, J S; Van der Mei, H C; Nixon, M; Eastwood, I M; Greenhalgh, M; Read, S J; Robson, G D; Handley, P S

1999-08-01

Initial adhesion of fungi to plasticized polyvinyl chloride (pPVC) may determine subsequent colonization and biodeterioration processes. The deteriogenic fungus Aureobasidium pullulans was used to investigate the physicochemical nature of adhesion to both unplasticized PVC (uPVC) and pPVC containing the plasticizers dioctyl phthalate (DOP) and dioctyl adipate (DOA). A quantitative adhesion assay using image analysis identified fundamental differences in the mechanism of adhesion of A. pullulans blastospores to these substrata. Adhesion to pPVC was greater than that to uPVC by a maximum of 280% after a 4-h incubation with 10(8) blastospores ml(-1). That plasticizers enhance adhesion to PVC was confirmed by incorporating a dispersion of both DOA and DOP into the blastospore suspension. Adhesion to uPVC was increased by up to 308% in the presence of the dispersed plasticizers. Hydrophobic interactions were found to dominate adhesion to uPVC because (i) a strong positive correlation was observed between substratum hydrophobicity (measured by using a dynamic contact angle analyzer) and adhesion to a range of unplasticized polymers including uPVC, and (ii) neither the pH nor the electrolyte concentration of the suspension buffer, both of which influence electrostatic interactions, affected adhesion to uPVC. In contrast, adhesion to pPVC is principally controlled by electrostatic interactions. Enhanced adhesion to pPVC occurred despite a relative reduction of 13 degrees in the water contact angle of pPVC compared to that of uPVC. Furthermore, adhesion to pPVC was strongly dependent on both the pH and electrolyte concentration of the suspension medium, reaching maximum levels at pH 8 and with an electrolyte concentration of 10 mM NaCl. Plasticization with DOP and DOA therefore increases adhesion of A. pullulans blastospores to pPVC through an interaction mediated by electrostatic forces.

Production of poly(β-l-malic acid) by Aureobasidium pullulans HA-4D under solid-state fermentation.

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Xia, Jun; Li, Rongqing; He, Aiyong; Xu, Jiaxing; Liu, Xiaoyan; Li, Xiangqian; Xu, Jiming

2017-11-01

Poly(β-l-malic acid) (PMA) production by Aureobasidium pullulans HA-4D was carried out through solid-state fermentation (SSF) using agro-industrial residues. Maximum PMA production (75.4mg/g substrate) was obtained from a mixed substrate of sweet potato residue and wheat bran (1:1, w/w) supplemented with NaNO 3 (0.8%, w/w) and CaCO 3 (2%, w/w), with an initial moisture content of 70% and inoculum size of 13% (v/w) for 8days. Repeated-batch SSF was successfully conducted for 5 cycles with a high productivity. The scanning electron microscopy showed that the yeast-like cells of A. pullulans HA-4D could grow well on the solid substrate surface. Moreover, the cost analysis showed that the unit price of PMA in SSF was much lower than that of SmF. This is the first report on PMA production via SSF, and this study provided a new method to produce PMA from inexpensive agro-industrial residues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of Antimicrobial Films by Incorporation of Partially Purified Lysozyme into Biodegradable Films of Crude Exopolysaccharides Obtained from Aureobasidium pullulans Fermentation

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Nilay Kandemir

2005-01-01

Full Text Available Antimicrobial films were produced by incorporating partially purified lysozyme into films of crude exopolysaccharides (59 % pullulan obtained from Aureobasidium pullulans fermentation. After film making, the films containing lysozyme at 100, 260, 520 and 780 μg/cm2 showed 23 to 70 % of their expected enzyme activities. The highest recovery of enzyme activity (65–70 % after the film making was obtained in films prepared by incorporating lysozyme at 260 μg/cm2 (1409 U/cm2. The incorporation of disodium EDTA×2H2O and sucrose did not affect the initial lysozyme activity of the films significantly. With or without the presence of disodium EDTA×2H2O at 52 or 520 μg/cm2, lysozyme activity showed sufficient stability in the films during 21 days of cold storage. However, the presence of sucrose at 10 mg/cm2 in the films caused the destabilization of part of enzyme activity (almost 35 % at the end of storage. The combinational incorporation of lysozyme at 780 μg/cm2 (4227 U/cm2 and disodium EDTA×2H2O at 520 μg/cm2 gave antimicrobial films effective on Escherichia coli. However, in the studied lysozyme concentration range the films did not show any antimicrobial activity against Lactobacillus plantarum. This study clearly showed that the partially purified lysozyme and crude exopolysaccharides from Aureobasidium pullulans may be used to obtain antimicrobial films to increase the safety of foods.

Effects of sugar and amino acid supplementation on Aureobasidium pullulans NRRL 58536 antifungal activity against four Aspergillus species.

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Prasongsuk, Sehanat; Ployngam, Saowaluck; Wacharasindhu, Sumrit; Lotrakul, Pongtharin; Punnapayak, Hunsa

2013-09-01

Cultured cell extracts from ten tropical strains of Aureobasidium pullulans were screened for antifungal activity against four pathogenic Aspergillus species (Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, and Aspergillus terreus) using the well diffusion and conidial germination inhibition assays. The crude cell extract from A. pullulans NRRL 58536 resulted in the greatest fungicidal activity against all four Aspergillus species and so was selected for further investigation into enhancing the production of antifungal activity through optimization of the culture medium, carbon source (sucrose and glucose) and amino acid (phenylalanine, proline, and leucine) supplementation. Sucrose did not support the production of any detectable antifungal activity, while glucose did with the greatest antifungal activity against all four Aspergillus species being produced in cells grown in medium containing 2.5 % (w/v) glucose. With respect to the amino acid supplements, variable trends between the different Aspergillus species and amino acid combinations were observed, with the greatest antifungal activities being obtained when grown with phenylalanine plus leucine supplementation for activity against A. flavus, proline plus leucine for A. terreus, and phenylalanine plus proline and leucine for A. niger and A. fumigatus. Thin layer chromatography, spectrophotometry, high-performance liquid chromatography, (1)H-nuclear magnetic resonance, and MALDI-TOF mass spectrometry analyses were all consistent with the main component of the A. pullulans NRRL 58536 extracts being aureobasidins.

Isolation and Characterization of melanized yeast form of Aureobasidium pullulans and physiological studies on the melanization process

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El-Gamal, M.S.; El-Bialy, H.A.; Elsayed, M.A.; Khalifa, M.A.

2017-01-01

Melanin pigments have immense application potentials in the fields of agriculture , cosmetics and pharmaceutical industries . Isolation and characterization of melanin producer from local resources is the main aim of the present study . Six melanized yeast isolates were selected from seventeen isolation resources including natural sources (Eucalyptus globules plant), industrial wastes (Tomato paste processing) and surface contaminants (Bathrooms). The selected yeasts were screened for melanin production in an individual experiment , results revealed the ability of yeast isolate selected from wastes of tomato paste processing (W 3 ) to produce melanin at 300 mM concentration . The selected melanized yeast was identified as Aureobasidium pullulans according to the morphological characteristics and 18S rRNA . Melanin production by the selected yeast was maximized by optimization of the cultural conditions and nutritional parameters by nearly two folds ( 550 mM ). The highest melanin yield was achieved in the fermentation medium contains 30 gl -1 sucrose , 35 gl -1 peptone and 1 mM L - DOPA concentration after nine days of incubation at 30°C and its pH value is adjusted at 7.0. Melanin characterization by FTIR and NMR resemble aliphatic and aromatic composition of A . pullulans ’ s melanin . In conclusion, the selected yeast is a promising candidate for melanin production in a semipilot scale

Production and Properties of a Thermostable, pH-Stable Exo-Polygalacturonase Using Aureobasidium pullulans Isolated from Saharan Soil of Algeria Grown on Tomato Pomace.

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Bennamoun, Leila; Hiligsmann, Serge; Dakhmouche, Scheherazad; Ait-Kaki, Amel; Labbani, Fatima-Zohra Kenza; Nouadri, Tahar; Meraihi, Zahia; Turchetti, Benedetta; Buzzini, Pietro; Thonart, Philippe

2016-10-29

Polygalacturonase is a valuable biocatalyst for several industrial applications. Production of polygalacturonase using the Aureobasidium pullulans stain isolated from Saharan soil of Algeria was investigated. Its capacity to produce polygalacturonase was assessed under submerged culture using tomato pomace as an abundant agro-industrial substrate. Optimization of the medium components, which enhance polygalacturonase activity of the strain Aureobasidium pullulans , was achieved with the aid of response surface methodology. The composition of the optimized medium was as follows: tomato pomace 40 g/L, lactose 1.84 g/L, CaCl₂0.09 g/L and pH 5.16. Practical validation of the optimum medium provided polygalacturonase activity of 22.05 U/mL, which was 5-fold higher than in unoptimized conditions. Batch cultivation in a 20 L bioreactor performed with the optimal nutrients and conditions resulted in a high polygalacturonase content (25.75 U/mL). The enzyme showed stability over a range of temperature (5-90 °C) with an optimum temperature of 60 °C with pH 5.0, exhibiting 100% residual activity after 1h at 60 °C. This enzyme was stable at a broad pH range (5.0-10). The enzyme proved to be an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of polygalacturonic acid. Moreover, the exo-polygalacturonase was able to enhance the clarification of both apple and citrus juice. As a result, an economical polygalacturonase production process was defined and proposed using an industrial food by-product.

Production and Properties of a Thermostable, pH—Stable Exo-Polygalacturonase Using Aureobasidium pullulans Isolated from Saharan Soil of Algeria Grown on Tomato Pomace

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Leila Bennamoun

2016-10-01

Full Text Available Polygalacturonase is a valuable biocatalyst for several industrial applications. Production of polygalacturonase using the Aureobasidium pullulans stain isolated from Saharan soil of Algeria was investigated. Its capacity to produce polygalacturonase was assessed under submerged culture using tomato pomace as an abundant agro-industrial substrate. Optimization of the medium components, which enhance polygalacturonase activity of the strain Aureobasidium pullulans, was achieved with the aid of response surface methodology. The composition of the optimized medium was as follows: tomato pomace 40 g/L, lactose 1.84 g/L, CaCl20.09 g/L and pH 5.16. Practical validation of the optimum medium provided polygalacturonase activity of 22.05 U/mL, which was 5-fold higher than in unoptimized conditions. Batch cultivation in a 20 L bioreactor performed with the optimal nutrients and conditions resulted in a high polygalacturonase content (25.75 U/mL. The enzyme showed stability over a range of temperature (5–90 °C with an optimum temperature of 60 °C with pH 5.0, exhibiting 100% residual activity after 1h at 60 °C. This enzyme was stable at a broad pH range (5.0–10. The enzyme proved to be an exo-polygalacturonase, releasing galacturonic acid by hydrolysis of polygalacturonic acid. Moreover, the exo-polygalacturonase was able to enhance the clarification of both apple and citrus juice. As a result, an economical polygalacturonase production process was defined and proposed using an industrial food by-product.

Introduction of Aureobasidium pullulans to the Phyllosphere of Organically Grown Strawberries with Focus on Its Establishment and Interactions with the Resident Microbiome

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Annette Reineke

2013-10-01

Full Text Available Currently, there is little knowledge of the establishment of repeatedly applied biological control agents (BCAs in the phyllosphere of plants and, in particular, their interactions with the resident microbiome. Under field conditions, the BCA Aureobasidium pullulans was applied as a model organism to organically grown strawberries during two subsequent years (2011, 2012, either as single strain treatment or with the co-application of the entomopathogenic fungus Beauveria bassiana. Fungal and bacterial communities of strawberry leaves were investigated by means of plate counts and 454 pyrosequencing. The establishment of the introduced A. pullulans strains considerably differed between the two years, presumably due to distinct environmental conditions. Short-term and long-term effects of BCA applications on the composition and diversity of fungal communities could be observed as a result of successful establishment of A. pullulans, in 2011, showing, for instance, reduced diversity of fungal communities by competitive displacement shortly after BCA introduction. Due to considerable dynamics in untreated resident microbial communities in the phyllosphere in general, however, we suggest that even the effects caused by the applied BCA preparations in 2011 are negligible under practical conditions.

Aureobasidium pullulansas a biocontrol agent of blue mold in "Rocha" pear.

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Ferreira-Pinto, M M; Moura-Guedes, M C; Barreiro, M G; Pais, I; Santos, M R; Silva, M J

2006-01-01

The blue mold of "Rocha" pear caused by Penicillium expansum is an important postharvest disease which is adequately controlled by application of synthetic fungicides. In recent years, strategies like biological control have been considered a desirable alternative to chemicals. Several studies have demonstrated the potential of the yeast-like fungus Aureobasidium pullulans for control of postharvest decay of pear. A Portuguese isolate of Aureobasidium pullulans was characterized and evaluated for its activity in reducing postharvest blue mold decay of "Rocha" pear caused by Penicillium expansum. Study of optimal conditions for antagonist growth was carried out in six different culture media. The effect of four maturity stages of fruits in the development of A. pullulans was also studied. Biocontrol studies were performed with two concentrations of the antagonist (3 x 10(8) and 4 x 10(9) CFU/ml). A. pullulans growth was significantly different (P Corn Meal Agar (CMA) and Potato Dextrose Agar (PDA) media which contains the higher concentration of glucose (20 mg/l). Medium resulted from fruits of the first harvest date presented lower colony diameter. Inoculation of A. pullulans at 3 x 10(8) and 4 x 10(9) CFU/ml reduced the incidence of the disease by 23 and 63%, and reduced the lesion diameter by 36 and 46%, respectively.

Effects of Two-stage Controlled pH and Temperature vs. One-step Process for Hemicellulase Biosynthesis and Feruloyl Oligosaccharide Fermentation using Aureobasidium pullulans

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Xiaohong Yu

2016-04-01

Full Text Available A two-stage, pH- and temperature-controlled wheat bran fermentation method using Aureobasidium pullulans was investigated for feruloyl oligosaccharides (FOs production and the activities of xylanase, xylosidase, and ferulic acid esterase (FAE. A. pullulans secreted xylanase, xylosidase, and FAE at high levels in the initial pH of 4.0 to 5.0 and a fermentation liquid temperature of 31 °C to 33 °C. FOs production via two-stage fermentation (FOs 2 reached 1123 nmol/L after fermentation for 96 h, by controlling the initial pH at 4.0 and the initial temperature at 33 °C, and then changing the pH to 6.0 and the temperature to 29 °C at the same time at 36 h. This process was 12 h shorter and 219 nmol/L higher than a one-stage fermentation for producing FOs 1. Xylanase, xylosidase, and FAE activities were highly correlated with controlled pH and temperature and FOs biosynthesis rate. Thus, the combination of two-stage controlled pH and temperature could support mass production of FOs.

Production of poly(malic acid) from sugarcane juice in fermentation by Aureobasidium pullulans: Kinetics and process economics.

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Wei, Peilian; Cheng, Chi; Lin, Meng; Zhou, Yipin; Yang, Shang-Tian

2017-01-01

Poly(β-l-malic acid) (PMA) is a biodegradable polymer with many potential biomedical applications. PMA can be readily hydrolyzed to malic acid (MA), which is widely used as an acidulant in foods and pharmaceuticals. PMA production from sucrose and sugarcane juice by Aureobasidium pullulans ZX-10 was studied in shake-flasks and bioreactors, confirming that sugarcane juice can be used as an economical substrate without any pretreatment or nutrients supplementation. A high PMA titer of 116.3g/L and yield of 0.41g/g were achieved in fed-batch fermentation. A high productivity of 0.66g/L·h was achieved in repeated-batch fermentation with cell recycle. These results compared favorably with those obtained from glucose and other biomass feedstocks. A process economic analysis showed that PMA could be produced from sugarcane juice at a cost of $1.33/kg, offering a cost-competitive bio-based PMA for industrial applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anti-skin-aging benefits of exopolymers from Aureobasidium pullulans SM2001.

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Kim, Kyung Hu; Park, Soo Jin; Lee, Ji Eun; Lee, Young Joon; Song, Chang Hyun; Choi, Seong Hun; Ku, Sae Kwang; Kang, Su Jin

2014-01-01

There have been many attempts to search for affordable and effective functional cosmetic ingredients, especially from natural sources. As research into developing a functional cosmetic ingredient, we investigated whether exopolymers from Aureobasidium pullulans SM2001 (E-AP-SM2001) exert antioxidant, antiwrinkle, whitening, and skin moisturizing effects. Antioxidant effects of E-AP-SM2001 were determined by measuring free radical scavenging capacity and superoxide dismutase (SOD)-like activity. Antiwrinkle effects were assessed through the inhibition of hyaluronidase, elastase, collagenase, and matrix metalloproteinase (MMP)-1. Whitening effects were measured by tyrosinase inhibition assay, and by melanin formation test in B16/F10 melanoma cells. Skin moisturizing effects were detected by mouse skin water content test. E-AP-SM2001 showed potent DPPH radical scavenging activity and SOD-like effects. Additionally, hyaluronidase, elastase, collagenase, and MMP-1 activities were significantly inhibited by E-AP-SM2001. We also observed that E-AP-SM2001 effectively reduced melanin production by B16/F10 melanoma cells and mushroom tyrosinase activities. Furthermore, significant increases in skin water content were detected in E-AP-SM2001- treated mouse skin, as compared with vehicle-treated control skin. Notably, a mask pack containing E-AP-SM2001 showed a >twofold more extensive moisturizing effect compared with one containing Saccharomycopsis ferment filtrate. Our results suggest that E-AP-SM2001 has adequate antiaging, antiwrinkle, and whitening benefits and skin moisturizing effect. These effects involve reducing hyaluronidase, elastase, collagenase, and MMP-1 activities, as well as inhibition of melanin production and tyrosinase activities. Therefore, the antioxidant E-AP-SM2001 may serve as a predictable functional ingredient.

Variations in grain lipophilic phytochemicals, proteins and resistance to Fusarium spp. growth during grain storage as affected by biological plant protection with Aureobasidium pullulans (de Bary).

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Wachowska, Urszula; Tańska, Małgorzata; Konopka, Iwona

2016-06-16

Modern agriculture relies on an integrated approach, where chemical treatment is reduced to a minimum and replaced by biological control that involves the use of active microorganisms. The effect of the antagonistic yeast-like fungus Aureobasidium pullulans on proteins and bioactive compounds (alkylresorcinols, sterols, tocols and carotenoids) in winter wheat grain and on the colonization of wheat kernels by fungal microbiota, mainly Fusarium spp. pathogens, was investigated. Biological treatment contributed to a slight increase contents of tocols, alkylresorcinols and sterols in grain. At the same time, the variation of wheat grain proteins was low and not significant. Application of A. pullulans enhanced the natural yeast colonization after six months of grain storage and inhibited growth of F. culmorum pathogens penetrating wheat kernel. This study demonstrated that an integrated approach of wheat grain protection with the use of the yeast-like fungus A. pullulans reduced kernel colonization by Fusarium spp. pathogens and increased the content of nutritionally beneficial phytochemicals in wheat grain without a loss of gluten proteins responsible for baking value. Copyright © 2016. Published by Elsevier B.V.

Optimization of physico-chemical and nutritional parameters for a novel pullulan-producing fungus, Eurotium chevalieri.

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Gaur, R; Singh, R; Tiwari, S; Yadav, S K; Daramwal, N S

2010-09-01

To isolate the novel nonmelanin pullulan-producing fungi from soil and to optimize the physico-chemical and nutritional parameters for pullulan production. A selective enrichment method was followed for the isolation, along with development of a suitable medium for pullulan production, using shake flask experiments. Pullulan content was confirmed using pure pullulan and pullulanase hydrolysate. Eurotium chevalieri was able to produce maximum pullulan (38 ± 1·0 g l(-1) ) at 35°C, pH 5·5, 2·5% sucrose, 0·3% ammonium sulfate and 0·2% yeast extract in a shake flash culture medium with an agitation rate of 30 rev min(-1) for 65 h. The novel pullulan-producing fungus was identified as E. chevalieri (MTCC no. 9614), which was able to produce nonmelanin pullulan at from poorer carbon and nitrogen sources than Aureobasidium pullulans and may therefore be useful for the commercial production of pullulan. Eurotium chevalieri could produce pullulan in similar amounts to A. pullulans. Therefore, in future, this fungus could also be used for commercial pullulan production, because it is neither polymorphic nor melanin producing, hence its handling during pullulan fermentation will be easier and more economical. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.

Media optimization for elevated molecular weight and mass production of pigment-free pullulan.

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Yu, Xiaoliu; Wang, Yulei; Wei, Gongyuan; Dong, Yingying

2012-07-01

In this study, an Aureobasidium pullulans SZU 1001 mutant, deficient in pigment production, was screened by complex UV and γ-ray mutagenesis. Medium composition optimization for increased pullulan molecular weight and production was conducted using this mutant. Six nutrients: yeast extract, (NH4)2SO4, K2HPO4, NaCl, MgSO4·7H2O and CaCl2 were detected within pullulan production in flasks. It is shown that NaCl and K2HPO4 have significant influences on molecular weight of pullulan, while yeast extract and (NH4)2SO4 significantly affect pullulan yield. To achieve a higher molecular weight and more efficient pullulan production, a response surface methodology approach was introduced to predict an optimal nutrient combination. A molecular weight of 5.74 × 10(6) and pullulan yield on glucose of 51.30% were obtained under batch pullulan fermentation with the optimized media, which increased molecular weight and pullulan production by 97.25% and 11.04%, respectively compared with the control media. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of plastic composite support and pH profiles on pullulan production in a biofilm reactor.

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Cheng, Kuan-Chen; Demirci, Ali; Catchmark, Jeffrey M

2010-04-01

Pullulan is a linear homopolysaccharide which is composed of glucose units and often described as alpha-1, 6-linked maltotriose. The applications of pullulan range from usage as blood plasma substitutes to environmental pollution control agents. In this study, a biofilm reactor with plastic composite support (PCS) was evaluated for pullulan production using Aureobasidium pullulans. In test tube fermentations, PCS with soybean hulls, defatted soy bean flour, yeast extract, dried bovine red blood cells, and mineral salts was selected for biofilm reactor fermentation (due to its high nitrogen content, moderate nitrogen leaching rate, and high biomass attachment). Three pH profiles were later applied to evaluate their effects on pullulan production in a PCS biofilm reactor. The results demonstrated that when a constant pH at 5.0 was applied, the time course of pullulan production was advanced and the concentration of pullulan reached 32.9 g/L after 7-day cultivation, which is 1.8-fold higher than its respective suspension culture. The quality analysis demonstrated that the purity of produced pullulan was 95.8% and its viscosity was 2.4 centipoise. Fourier transform infrared spectroscopy spectra also supported the supposition that the produced exopolysaccharide was mostly pullulan. Overall, this study demonstrated that a biofilm reactor can be successfully implemented to enhance pullulan production and maintain its high purity.

Extracellular polysaccharides purified from Aureobasidium pullulans SM-2001 (Polycan) inhibit dexamethasone-induced muscle atrophy in mice

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Cho, Hyung-Rae; Park, Dong-Chan; Jung, Go-Woon

2018-01-01

The present study assessed the beneficial skeletal muscle-preserving effects of extracellular polysaccharides from Aureobasidium pullulans SM-2001 (Polycan) (EAP) on dexamethasone (DEXA)-induced catabolic muscle atrophy in mice. To investigate whether EAP prevented catabolic DEXA-induced muscle atrophy, and to examine its mechanisms of action, EAP (100, 200 and 400 mg/kg) was administered orally, once a day for 24 days. EAP treatment was initiated 2 weeks prior to DEXA treatment (1 mg/kg, once a day for 10 days) in mice. Body weight alterations, serum biochemistry, calf thickness, calf muscle strength, gastrocnemius muscle thickness and weight, gastrocnemius muscle antioxidant defense parameters, gastrocnemius muscle mRNA expression, histology and histomorphometry were subsequently assessed. After 24 days, DEXA control mice exhibited muscle atrophy according to all criteria indices. However, these muscle atrophy symptoms were significantly inhibited by oral treatment with all three doses of EAP. Regarding possible mechanisms of action, EAP exhibited favorable ameliorating effects on DEXA-induced catabolic muscle atrophy via antioxidant and anti-inflammatory effects; these effects were mediated by modulation of the expression of genes involved in muscle protein synthesis (AKT serine/threonine kinase 1, phosphatidylinositol 3-kinase, adenosine A1 receptor and transient receptor potential cation channel subfamily V member 4) and degradation (atrogin-1, muscle RING-finger protein-1, myostatin and sirtuin 1). Therefore, these results indicated that EAP may be helpful in improving muscle atrophies of various etiologies. EAP at 400 mg/kg exhibited favorable muscle protective effects against DEXA-induced catabolic muscle atrophy, comparable with the effects of oxymetholone (50 mg/kg), which has been used to treat various muscle disorders. PMID:29138805

Cofactor and CO2 donor regulation involved in reductive routes for polymalic acid production by Aureobasidium pullulans CCTCC M2012223.

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Zou, Xiang; Tu, Guangwei; Zan, Zhanquan

2014-10-01

Polymalic acid (PMA) is a water-soluble polyester with many attractive properties for biomedical application. Its monomer L-malic acid is widely used in the food industry and also a potential C4 platform chemical. Cofactor and CO2 donor involved in the reductive routes were investigated for PMA production by Aureobasidium pullulans. Biotin as the key cofactor of pyruvate carboxylase was favor for the PMA biosynthesis. Na2CO3 as CO2 donor can obviously improved PMA titer when compared with no CO2 supplier NaOH, and also exhibit more advantages than the other donor CaCO3 because of its water-soluble characteristic. A combinational process with addition of biotin 70 mg/L and Na2CO3 as the CO2 donor was scaled-up in 50 L fermentor, achieving the high product 34.3 g/L of PMA and productivity of 0.41 g/L h. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application.

Cloning, characterization, expression and antifungal activity of an alkaline serine protease of Aureobasidium pullulans PL5 involved in the biological control of postharvest pathogens.

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Zhang, Dianpeng; Spadaro, Davide; Valente, Silvia; Garibaldi, Angelo; Gullino, Maria Lodovica

2012-02-15

An alkaline protease gene was amplified from genomic DNA and cDNA of the antagonistic yeast-like fungus Aureobasidium pullulans PL5, a biocontrol agent effective against Monilinia laxa on stone fruit and Botrytis cinerea and Penicillium expansum on pome fruits. An open reading frame of 1248 bp encoding a 415-amino acid (aa) protein with a calculated molecular weight (M(r)) of 42.9 kDa and an isoelectric point (pI) of 4.5 was characterized. The cDNAALP5 gene had an 18-amino acid signal peptide, one N-gylcosylation, one histidine active site, and one serine active site. The ALP5 gene with a M(r) of 1351 bp contained two introns. One intron was of 54 bp, while the other was of 50 bp. Protein BLAST and phylogenetic tree analysis of the deduced amino sequences from the cDNAALP5 gene showed that the encoded protein had 100% homology to a protease enzyme (ALP2) of a sea strain of A. pullulans, suggesting that the protein ALP5 was an alkaline serine protease. Expression of ALP5 in Escherichia coli BL21 (DE3), followed by identification with Western-blotting, purification with Ni-NTA and analysis of enzymatic activity, yielded an homogeneous recombinant ALP5 which hydrolysed the substrate casein and inhibited the mycelial growth of the pathogens. At its optimal pH of 10.0 and reaction temperature of 50°C, the recombinant protease exhibited the highest activity towards the substrate casein, though the highest stability was at lower temperatures and pH between 7.0 and 9.0. This study provided the direct evidence that extracellular proteases secreted by the antagonist A. pullulans PL5 played a role in the biocontrol activities against some postharvest pathogens of apple and peach. Copyright © 2011 Elsevier B.V. All rights reserved.

Partial Optimization of Endo-1, 4-Β-Xylanase Production by Aureobasidium pullulansUsing Agro-Industrial Residues

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Shaghayegh Nasr

2013-12-01

This finding indicates the feasibility of growing of A. pullulans strain SN090 on wheat bran as an alternate economical substrate in order for reducing the costs of enzyme production and using this fortified agro-industrial byproduct in formulation of animal feed.

Occurrence and infection of Cladosporium, Fusarium, Epicoccum and Aureobasidium in withered rotten grapes during post-harvest dehydration.

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Lorenzini, Marilinda; Zapparoli, Giacomo

2015-11-01

Fungi like Cladosporium, Fusarium, Epicoccum and Aureobasidium can occur on withered grapes causing spoilage of passito wine. There is little or no information on the pathogenic role of these fungi. This study describes the isolation, incidence and identification of several isolates from different withered rotten grapes. Representative isolates grouped in several phenotypes were identified by phylogenetic analysis of internal transcribed spacer, actin or elongation factor gene sequences. Isolates of Cladosporium and Fusarium were ascribed to different species, of these C. ramotenellum, C. halotolerans and F. graminearum were isolated from Vitis vinifera for the first time. All Epicoccum and Aureobasidium isolates belonged to E. nigrum and A. pullulans, respectively. Random amplified DNA polymorphism analysis showed high level of heterogenicity among Epicoccum and Fusarium isolates. Infection assays were carried out to evaluate infectivity in some strains under different withering conditions. Fusarium spp. strains had similar infectivity, while significant variability was observed among Cladosporium spp. and E. nigrum strains. A. pullulans resulted particularly infective. This study provided insights into the occurrence and infection of these fungi in fruit-drying rooms with important implications towards control management during the withering.

A novel biosurfactant produced by Aureobasidium pullulans L3-GPY from a tiger lily wild flower, Lilium lancifolium Thunb.

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Kim, Jong Shik; Lee, In Kyoung; Yun, Bong Sik

2015-01-01

Yeast biosurfactants are important biotechnological products in the food industry, and they have medical and cosmeceutical applications owing to their specific modes of action, low toxicity, and applicability. Thus, we have isolated and examined biosurfactant-producing yeast for various industrial and medical applications. A rapid and simple method was developed to screen biosurfactant-producing yeasts for high production of eco-friendly biosurfactants. Using this method, several potential niches of biosurfactant-producing yeasts, such as wild flowers, were investigated. We successfully selected a yeast strain, L3-GPY, with potent surfactant activity from a tiger lily, Lilium lancifolium Thunb. Here, we report the first identification of strain L3-GPY as the black yeast Aureobasidium pullulans. In addition, we isolated a new low-surface-tension chemical, designated glycerol-liamocin, from the culture supernatant of strain L3-GPY through consecutive chromatography steps, involving an ODS column, solvent partition, silica gel, Sephadex LH-20, and an ODS Sep-Pak cartridge column. The chemical structure of glycerol-liamocin, determined by mass spectrometry and nuclear magnetic resonance spectroscopy, indicates that it is a novel compound with the molecular formula C33H62O12. Furthermore, glycerol-liamocin exhibited potent biosurfactant activity (31 mN/m). These results suggest that glycerol-liamocin is a potential novel biosurfactantfor use in various industrial applications.

Effects of nitrogen availability on polymalic acid biosynthesis in the yeast-like fungus Aureobasidium pullulans.

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Wang, Yongkang; Song, Xiaodan; Zhang, Yongjun; Wang, Bochu; Zou, Xiang

2016-08-22

Polymalic acid (PMA) is a novel polyester polymer that has been broadly used in the medical and food industries. Its monomer, L-malic acid, is also a potential C4 platform chemical. However, little is known about the mechanism of PMA biosynthesis in the yeast-like fungus, Aureobasidium pullulans. In this study, the effects of different nitrogen concentration on cell growth and PMA biosynthesis were investigated via comparative transcriptomics and proteomics analyses, and a related signaling pathway was also evaluated. A high final PMA titer of 44.00 ± 3.65 g/L (49.9 ± 4.14 g/L of malic acid after hydrolysis) was achieved in a 5-L fermentor under low nitrogen concentration (2 g/L of NH4NO3), which was 18.3 % higher yield than that obtained under high nitrogen concentration (10 g/L of NH4NO3). Comparative transcriptomics profiling revealed that a set of genes, related to the ribosome, ribosome biogenesis, proteasome, and nitrogen metabolism, were significantly up- or down-regulated under nitrogen sufficient conditions, which could be regulated by the TOR signaling pathway. Fourteen protein spots were identified via proteomics analysis, and were found to be associated with cell division and growth, energy metabolism, and the glycolytic pathway. qRT-PCR further confirmed that the expression levels of key genes involved in the PMA biosynthetic pathway (GLK, CS, FUM, DAT, and MCL) and the TOR signaling pathway (GS, TOR1, Tap42, and Gat1) were upregulated due to nitrogen limitation. Under rapamycin stress, PMA biosynthesis was obviously inhibited in a dose-dependent manner, and the transcription levels of TOR1, MCL, and DAT were also downregulated. The level of nitrogen could regulate cell growth and PMA biosynthesis. Low concentration of nitrogen was beneficial for PMA biosynthesis, which could upregulate the expression of key genes involved in the PMA biosynthesis pathway. Cell growth and PMA biosynthesis might be mediated by the TOR signaling pathway in

Production of Cellulolytic and Hemicellulolytic Enzymes From Aureobasidium pulluans on Solid State Fermentation

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Leite, Rodrigo Simões Ribeiro; Bocchini, Daniela Alonso; da Silva Martins, Eduardo; Silva, Dênis; Gomes, Eleni; da Silva, Roberto

This article investigates a strain of the yeast Aureobasidium pullulans for cellulase and hemicellulase production in solid state fermentation. Among the substrates analyzed, the wheat bran culture presented the highest enzymatic production (1.05 U/mL endoglucanase, 1.3 U/mL β-glucosidase, and 5.0 U/mL xylanase). Avicelase activity was not detected. The optimum pH and temperature for xylanase, endoglucanase and β-glucosidase were 5.0 and 50, 4.5 and 60, 4.0 and 75°C, respectively. These enzymes remained stable between a wide range of pH. The β-glucosidase was the most thermostable enzyme remaining 100% active when incubated at 75°C for 1 h.

Effect of Meadowsweet Flower Extract-Pullulan Coatings on Rhizopus Rot Development and Postharvest Quality of Cold-Stored Red Peppers

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Alicja Synowiec

2014-08-01

Full Text Available The study involved an examination of the antifungal activity on red peppers of pullulan coating (P and pullulan coating containing either water-ethanol (P + eEMF or ethanol extract of meadowsweet flowers (P + eEMF. Pullulan was obtained from a culture of Aureobasidium pullulans B-1 mutant. Both non-inoculated peppers and those artificially inoculated with Rhizopus arrhizus were coated and incubated at 24 °C for 5 days. The intensity of the decay caused by Rhizopus arrhizus in the peppers with P and P + eEMF coatings was nearly 3-fold lower, and in the case of P + weEMF 5-fold lower, than that observed in the control peppers. Additionally, the P + weEMF coating decreased, almost two-fold the severity of pepper decay compared to other samples. The influence of coating of pepper postharvest quality was examined after 30 days of storage at 6 °C and 70%–75% RH. All coatings formed a thin and well-attached additional layer of an intensified gloss. During storage, color, total soluble solid content and weight loss of coated peppers were subject to lower changes in comparison with uncoated ones. The results indicate the possibility of the application of pullulan coatings containing MFEs as an alternative to the chemical fungicides used to combat pepper postharvest diseases.

Production of novel types of antibacterial liamocins by diverse strains of Aureobasidium pullulans grown on different culture media

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Objective: The objective was to compare production of antibacterial liamocins by diverse strains of A. pullulans grown on different culture media. Results: Liamocins produced by strains of A. pullulans have potential agricultural and pharmaceutical applications as antibacterials with specificity aga...

40 CFR 23.11 - Holidays.

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2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Holidays. 23.11 Section 23.11... STATUTES § 23.11 Holidays. If the date determined under §§ 23.2 to 23.10 falls on a Federal holiday, then... that is not a Federal holiday. ...

HLC/pullulan and pullulan hydrogels: their microstructure, engineering process and biocompatibility

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Li, Xian [College of chemistry & materials science, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China); Shaanxi Key Laboratory of Degradable Biomedical Materials, Department of Chemical Engineering, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China); Xue, Wenjiao [Shannxi provincial institute of microbiology, Xi’ an 710043 (China); Liu, Yannan; Li, Weina [Shaanxi Key Laboratory of Degradable Biomedical Materials, Department of Chemical Engineering, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China); Fan, Daidi, E-mail: fandaidi@nwu.edu.cn [Shaanxi Key Laboratory of Degradable Biomedical Materials, Department of Chemical Engineering, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China); Zhu, Chenhui [Shaanxi Key Laboratory of Degradable Biomedical Materials, Department of Chemical Engineering, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China); Wang, Yaoyu, E-mail: wyaoyu@nwu.edu.cn [College of chemistry & materials science, Northwest University, Taibai North Road 229, Xi’an, Shaanxi 710069 (China)

2016-01-01

New locally injectable biomaterials that are suitable for use as soft tissue fillers are needed to address a significant unmet medical need. In this study, we used pullulan and human-like collagen (HLC) based hydrogels with various molecular weights (MWs) in combination therapy against tissue defects. Briefly, pullulan was crosslinked with NaIO{sub 4} to form a pullulan hydrogel and then may coupled with HLC using the reaction between the –NH{sub 2} end-group of HLC and the –CHO group present on the aldehyde pullulan to form the HLC/pullulan hydrogel, wherein the NaIO{sub 4} acted as the crosslinking and oxidizing agent. The good miscibility of pullulan and HLC in the hydrogels was confirmed via Fourier transform infrared spectroscopy, scanning electron microscopy, compression testing, enzyme degradation testing, cell adhesions, live/dead staining and subcutaneous filling assays. Here, pullulan hydrogels with various MWs were fabricated and physicochemically characterized. Limitations of the pullulan hydrogels included inflammation, poor mechanical strength, and degradation. By contrast, the properties of the HLC/pullulan hydrogels strongly enhanced. The efficacy of these hydrogels was evaluated both in vitro and in vivo. Our results indicate that HLC/pullulan hydrogels may have therapeutic value as efficient soft tissue fillers, with reduced inflammation, improved cell adhesion and delayed hydrogel degradation. - Graphical abstract: The HLC/pullulan hydrogels were prepared by dialysis, wet granulation and UV radiation after various MWs of pullulan and HLC were crosslinked with NaIO{sub 4}, and injected subcutaneously into Kunming mouse. The formation of HLC/pullulan hydrogels is due to the amide bond linkage with the amino group of HLC and the aldehyde groups in pullulan aqueous media after crosslinking by NaIO{sub 4}. HLC/pullulan hydrogels may have therapeutic value as efficient soft tissue fillers, with reduced inflammation, improved cell adhesion and

QUANTITATIVE IMAGING AND STATISTICAL ANALYSIS OF FLUORESCENCE IN SITU HYBRIDIZATION (FISH) OF AUREOBASIDIUM PULLULANS. (R823845)

Science.gov (United States)

AbstractImage and multifactorial statistical analyses were used to evaluate the intensity of fluorescence signal from cells of three strains of A. pullulans and one strain of Rhodosporidium toruloides, as an outgroup, hybridized with either a universal o...

A carboxymethyl cellulase from a marine yeast ( Aureobasidium pullulans 98): Its purification, characterization, gene cloning and carboxymethyl cellulose digestion

Science.gov (United States)

Rong, Yanjun; Zhang, Liang; Chi, Zhenming; Wang, Xianghong

2015-10-01

We have reported that A. pullulans 98 produces a high yield of cellulase. In this study, a carboxymethyl cellulase (CMCase) in the supernatant of the culture of A. pullulans 98 was purified to homogeneity, and the maximum production of CMCase was 4.51 U (mg protein)-1. The SDS-PAGE analysis showed that the molecular mass of the purified CMCase was 67.0 kDa. The optimal temperature of the purified enzyme with considerable thermosensitivity was 40°C, much lower than that of the CMCases from other fungi. The optimal pH of the enzyme was 5.6, and the activity profile was stable in a range of acidity (pH 5.0-6.0). The enzyme was activated by Na+, Mg2+, Ca2+, K+, Fe2+ and Cu2+, however, it was inhibited by Fe3+, Ba2+, Zn2+, Mn2+ and Ag+. K m and V max values of the purified enzyme were 4.7 mg mL-1 and 0.57 µmol L-1 min-1 (mg protein)-1, respectively. Only oligosaccharides with different sizes were released from carboxymethylcellulose (CMC) after hydrolysis with the purified CMCase. The putative gene encoding CMCase was cloned from A. pullulans 98, which contained an open reading frame of 954 bp (EU978473). The protein deduced contained the conserved domain of cellulase superfamily (glucosyl hydrolase family 5). The N-terminal amino acid sequence of the purified CMCase was M-A-P-H-A-E-P-Q-S-Q-T-T-E-Q-T-S-S-G-Q-F, which was consistent with that deduced from the cloned gene. This suggested that the purified CMCase was indeed encoded by the cloned CMCase gene in this yeast.

12 CFR 231.1 - Authority, purpose, and scope.

Science.gov (United States)

2010-01-01

... markets. This part expands the Act's definition of “financial institution” to allow more financial market... SYSTEM NETTING ELIGIBILITY FOR FINANCIAL INSTITUTION (REGULATION EE) § 231.1 Authority, purpose, and.... 4401-4407). This part does not affect the status of those financial institutions specifically defined...

Optimization of physico-chemical and nutritional parameters for ...

African Journals Online (AJOL)

Optimization of physico-chemical and nutritional parameters for pullulan production by a mutant of thermotolerant Aureobasidium pullulans, in fed batch ... minutes, having killing rate of 70% level, produced 6 g l-1 higher pullulan as compared to the wild type without loosing thermotolerant and non-melanin producing ability.

Cloning, recombinant expression and characterization of a new ...

African Journals Online (AJOL)

A new amylase gene APGA1 was cloned from Aureobasidium pullulans NRRL 12974 and expressed in Pichia pastoris. This is the first report on cloning and expression of amylolytic gene from the industrially important microorganism A. pullulans. The purified recombinant protein with MW of 66 kDa and specific activity of ...

Production of pullulan from raw potato starch hydrolysates by a new strain of Auerobasidium pullulans.

Science.gov (United States)

Wu, Shengjun; Lu, Mingsheng; Chen, Jing; Fang, Yaowei; Wu, Leilei; Xu, Yan; Wang, Shujun

2016-01-01

In the present study, hydrolysis of potato starch with marine cold-adapted α-amylase and pullulan production from the hydrolysates by a new strain of Auerobasidium pullulans isolated from sea mud were conducted. The hydrolysis conditions were optimized as follows: reaction time 2h, pH 6.5, temperature 20°C, and α-amylase amount 12 U/g. Under these optimum hydrolysis conditions, the DE value of the potato starch hydrolysates reached to 49.56. The potato starch hydrolysates consist of glucose, maltose, isomaltose, maltotriose, and trace of other maltooligosaccharides with degree of polymerization ranged 4-7. The maximum production of pullulan at 96 h from the hydrolysate of potato starch was 36.17 g/L, which was higher than those obtained from glucose (22.07 g/L, p<0.05) and sucrose (31.42 g/L, p<0.05). Analysis of the high performance liquid chromatography of the hydrolysates of the pullulan product with pullulanase indicated that the main composition is maltotriose, thus confirming the pullulan structure of this pullulan product. Copyright © 2015 Elsevier B.V. All rights reserved.

Optimization of physico-chemical and nutritional parameters for ...

African Journals Online (AJOL)

hope&shola

2010-10-25

Oct 25, 2010 ... industrial production in order to reduce the cost of production. ... is of great economic importance with increased appli- ... industries (Seviour et al., 1992; Leathers, 2003). .... The various process parameters influencing pullulan production ..... formation by Aureobasidium pullulans in stirred tanks. Enzyme.

40 CFR 52.2311 - Motor vehicle antitampering.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Motor vehicle antitampering. 52.2311... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Texas § 52.2311 Motor vehicle... Emissions from Motor Vehicles” and 114.5 “Exclusions and Exceptions” on February 24, 1989, and September 6...

Aureobasidium melanogenum: a native of dark biofinishes on oil treated wood.

Science.gov (United States)

van Nieuwenhuijzen, Elke J; Houbraken, Jos A M P; Meijer, Martin; Adan, Olaf C G; Samson, Robert A

2016-05-01

The genus Aureobasidium, which is known as a wood staining mould, has been detected on oil treated woods in the specific stain formation called biofinish. This biofinish is used to develop a new protective, self-healing and decorative biotreatment for wood. In order to understand and control biofinish formation on oil treated wood, the occurrence of different Aureobasidium species on various wood surfaces was studied. Phenotypic variability within Aureobasidium strains presented limitations of morphological identification of Aureobasidium species. PCR amplification and Sanger sequencing of ITS and RPB2 were used to identify the culturable Aureobasidium species composition in mould stained wood surfaces with and without a biofinish. The analysed isolates showed that several Aureobasidium species were present and that Aureobasidium melanogenum was predominantly detected, regardless of the presence of a biofinish and the type of substrate. A. melanogenum was detected on wood samples exposed in the Netherlands, Cameroon, South Africa, Australia and Norway. ITS-specific PCR amplification, cloning and sequencing of DNA extracted from biofinish samples confirmed results of the culturing based method: A. melanogenum is predominant within the Aureobasidium population of biofinishes on pine sapwood treated with raw linseed oil and the outdoor placement in the Netherlands.

Eudragit E100 and Polysaccharide Polymer Blends as Matrices for ...

African Journals Online (AJOL)

Methods: LB, SCMC and E100 were blended in their dry (as purchased) state or modified by aqueous blending and subsequent lyophilization, prior to use as matrices in tablets. ... pullulan from Aureobasidium pullulans, 3-(3,4- .... the frozen polymer before sublimation and drying). Subsequently, milling generated a more.

Silk fibroin/pullulan blend films: Preparation and characterization

Energy Technology Data Exchange (ETDEWEB)

Shivananda, C. S.; Rao, B. Lakshmeesha; Madhukumar, R.; Asha, S. [Department of Studies in Physics, Mangalore University, Mangalagangotri – 574 199 (India); Sarojini, B. K. [Department of Industrial Chemistry, Mangalore University, Mangalagangotri, Mangalore –574 199 (India); Somashekhar, R. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore – 570 006 (India); Sangappa, Y., E-mail: syhalabhavi@yahoo.co.in [Department of Studies in Physics, Mangalore University, Mangalagangotri – 574 199 (India); School of Material Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

2016-05-23

In this work silk fibroin/pullulan blend films have been prepared by solution casting method. The blend films were examined for structural, and thermal properties using X-ray diffraction (XRD), thermogravimatric (TGA) and differential scanning calorimetry (DSC) analysis. The XRD results indicate that with the introduction of pullulan, the interaction between SF and pullulan in the blend films induced the conformation transition of SF films and amorphous phase increases with increasing pullulan ratio. The thermal properties of the blend films were improved significantly in the blend films.

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Box and other house cars built or placed in... APPLIANCE STANDARDS § 231.1 Box and other house cars built or placed in service before October 1, 1966. Except for box and other house cars that comply with either § 231.27 or § 231.28, each box and other...

The Synergism of Chemical Herbicides and Aureobasidium pullulans for Control Cleavers (Galium aparine L.) in Wheat

Institute of Scientific and Technical Information of China (English)

Liang CHENG

2015-01-01

Aureobasidium pul ulans, a biocontrol agent for the annual weed Galium aparine L. was evaluated in vitro for its compatibility with commercial formulation of five herbicides at 1X (recommended field rate), 0.5X, 0.2X, 0.1X, 0.067X, and 0.05X concentrations. Germination of A. pul ulans with paraquat, 2, 4-D, quizalofop-p, and clethodim treatment appeared reduced compared with germination of A. pul ulans with fluroxypyr treatment at al concentrations. Stunted and shorter germ tubes in comparison with the control were observed with 2, 4-D, quizalofop-p, and clethodim at 0.2X. Al concentration of paraquat, 2, 4-D, quizalofop-p, and clethodim except 0.05X, significantly decreased radial growth of A. pul ulans compared with its growth on the untreated PDA medium. Field trials to further develop A. pul ulans as bio-control agent for control G. aparine L. was conducted to test the effectiveness of this fungus in wheat plots for 2 years at the same location in Xining. Treatments included spore suspensions of A. pul ulans alone, a mixture of both fungus and fluroxypyr in wheat. Biocontrol agent effectiveness was estimated at approximately 7 and 14 days after treatment, as disease incidence, percent weed control, and weed biomass reduction. Significant reduction in weed biomass occurred in combination treatments, and potential exists to tank mix A. pul ulans with fluroxypyr. Leaf surface moisture and air temperatures fol owing application may account for inconsistencies in field results between years. This fungal organisms show potential as bioherbicides for weeds in G. aparine L.

An alternative anionic bio-sustainable anti-fungal agent: Investigation of its mode of action on the fungal cell membrane.

Science.gov (United States)

Stenbæk, Jonas; Löf, David; Falkman, Peter; Jensen, Bo; Cárdenas, Marité

2017-07-01

The potential of a lactylate (the sodium caproyl lactylate or C10 lactylate), a typical food grade emulsifier, as an anionic environmental friendly anti-fungal additive was tested in growth medium and formulated in a protective coating for exterior wood. Different laboratory growth tests on the blue stain fungus Aureobasidium pullulans were performed and its interactions on a model fungal cell membrane were studied. Promising short term anti-fungal effects in growth tests were observed, although significant but less dramatic effects took place in coating test on wood panels. Scanning electron microscope analysis shows clear differences in the amount of fungal slime on the mycelium of Aureobasidium pullulans when the fungus was exposed of C10 lactylate. This could indicate an effect on the pullulan and melanin production by the fungus. Moreover, the interaction studies on model fungal cell membranes show that C10 lactylate affects the phospholipid bilayer in a similar manner to other negative charged detergents. Copyright © 2017 Elsevier Inc. All rights reserved.

Exceptional oxygen barrier performance of pullulan nanocomposites with ultra-low loading of graphene oxide

Science.gov (United States)

Uysal Unalan, Ilke; Wan, Chaoying; Figiel, Łukasz; Olsson, Richard T.; Trabattoni, Silvia; Farris, Stefano

2015-07-01

Polymer nanocomposites are increasingly important in food packaging sectors. Biopolymer pullulan is promising in manufacturing packaging films or coatings due to its excellent optical clarity, mechanical strength, and high water-solubility as compared to other biopolymers. This work aims to enhance its oxygen barrier properties and overcome its intrinsic brittleness by utilizing two-dimensional planar graphene oxide (GO) nanoplatelets. It has been found that the addition of only 0.2 wt% of GO enhanced the tensile strength, Young’s modulus, and elongation at break of pullulan films by about 40, 44 and 52%, respectively. The light transmittance at 550 nm of the pullulan/GO films was 92.3% and haze values were within 3.0% threshold, which meets the general requirement for food packaging materials. In particular, the oxygen permeability coefficient of pullulan was reduced from 6337 to 2614 mL μm m-2 (24 h-1) atm-1 with as low as 0.05 wt% of GO loading and further to 1357 mL μm m-2 (24 h-1) atm-1 when GO concentration reached 0.3 wt%. The simultaneous improvement of the mechanical and oxygen barrier properties of pullulan was ascribed to the homogeneous distribution and prevalent unidirectional alignment of GO nanosheets, as determined from the characterization and theoretical modelling results. The exceptional oxygen barrier properties of pullulan/GO nanocomposites with enhanced mechanical flexibility and good optical clarity will add new values to high performance food packaging materials.

Oxidative stability of pullulan electrospun fibers containing fish oil

DEFF Research Database (Denmark)

García Moreno, Pedro Jesús; Damberg, Cecilie; Chronakis, Ioannis S.

2017-01-01

The effect of oil content and addition of natural antioxidants on the morphology and oxidative stability of pullulan ultra-thin fibers loaded with fish oil and obtained by electrospinning was investigated. Pullulan sub-micron fibers containing 10 and 30wt% fish oil were prepared and both presented...... into food matrices. These results show the feasibility to encapsulate fish oil in pullulan ultra-thin fibers and to improve their oxidative stability by adding natural antioxidants such as δ-tocopherol and rosemary extract. Therefore, this study might open up new opportunities for further technological...... development in the production of omega-3 nanodelivery systems, which have potential applications in different types of fortified foods. Encapsulation of fish oil in electrospun pullulan fibers stabilized by natural antioxidants....

Biodiesel production from Jatropha curcas oil catalyzed by whole ...

African Journals Online (AJOL)

my mord

2013-07-03

Jul 3, 2013 ... catalyzed by whole cells of Aureobasidium pullulans var. melanogenum ... friendly and renewable fuel that can be used directly in diesel engines ... methanol (or supercritical ethanol) transesterification is not commercially ...

Occurrence and diversity of marine yeasts in Antarctica environments

Science.gov (United States)

Zhang, Xue; Hua, Mingxia; Song, Chunli; Chi, Zhenming

2012-03-01

A total of 28 yeast strains were obtained from the sea sediment of Antarctica. According to the results of routine identification and molecular characterization, the strains belonged to species of Yarrowia lipolytica, Debaryomyces hansenii, Rhodotorula slooffiae, Rhodotorula mucilaginosa, Sporidiobolus salmonicolor, Aureobasidium pullulans, Mrakia frigida and Guehomyces pullulans, respectively. The Antarctica yeasts have wide potential applications in biotechnology, for some of them can produce β-galactosidase and killer toxins.

(Cu, Zn) واﻟﺳﻣﺎد اﻟﻌﻧﺎﺻر اﻟﺻﻐرى اﻟﻧﺷﺎط اﻟﻣﯾﮐروﺑﯾوﻟوﺟﻲ ﻟﺗر

African Journals Online (AJOL)

Aureobasidium Pullulans. وَ. Candida ablicans ... أﯾﺿﺎً ﮐﺎﻧت أﺑﺣﺎث. [14]. اﻟﺗﻲ وﺟدا ﻓﯾﮭﺎ أن. )Auerobasidium pullulans(. ﺗﺳﺗطﯾﻊ إﻧﺗﺎج. اﻟﻣﯾﻼﻧﯾن. (Melanin). وھذا ﯾﺳﺗﺣث إﻧ. زﯾم.

Exceptional oxygen barrier performance of pullulan nanocomposites with ultra-low loading of graphene oxide

International Nuclear Information System (INIS)

Unalan, Ilke Uysal; Farris, Stefano; Wan, Chaoying; Figiel, Łukasz; Olsson, Richard T; Trabattoni, Silvia

2015-01-01

Polymer nanocomposites are increasingly important in food packaging sectors. Biopolymer pullulan is promising in manufacturing packaging films or coatings due to its excellent optical clarity, mechanical strength, and high water-solubility as compared to other biopolymers. This work aims to enhance its oxygen barrier properties and overcome its intrinsic brittleness by utilizing two-dimensional planar graphene oxide (GO) nanoplatelets. It has been found that the addition of only 0.2 wt% of GO enhanced the tensile strength, Young’s modulus, and elongation at break of pullulan films by about 40, 44 and 52%, respectively. The light transmittance at 550 nm of the pullulan/GO films was 92.3% and haze values were within 3.0% threshold, which meets the general requirement for food packaging materials. In particular, the oxygen permeability coefficient of pullulan was reduced from 6337 to 2614 mL μm m"−"2 (24 h"−"1) atm"−"1 with as low as 0.05 wt% of GO loading and further to 1357 mL μm m"−"2 (24 h"−"1) atm"−"1 when GO concentration reached 0.3 wt%. The simultaneous improvement of the mechanical and oxygen barrier properties of pullulan was ascribed to the homogeneous distribution and prevalent unidirectional alignment of GO nanosheets, as determined from the characterization and theoretical modelling results. The exceptional oxygen barrier properties of pullulan/GO nanocomposites with enhanced mechanical flexibility and good optical clarity will add new values to high performance food packaging materials. (paper)

Synthesis and Characterization of Self-Assembled Nanogels Made of Pullulan

Directory of Open Access Journals (Sweden)

Sílvia A. Ferreira

2011-03-01

Full Text Available Self-assembled nanogels made of hydrophobized pullulan were obtained using a versatile, simple, reproducible and low-cost method. In a first reaction pullulan was modified with hydroxyethyl methacrylate or vinyl methacrylate, further modified in the second step with hydrophobic 1-hexadecanethiol, resulting as an amphiphilic material, which self-assembles in water via the hydrophobic interaction among alkyl chains. Structural features, size, shape, surface charge and stability of the nanogels were studied using hydrogen nuclear magnetic resonance, fluorescence spectroscopy, cryo-field emission scanning electron microscopy and dynamic light scattering. Above the critical aggregation concentration spherical polydisperse macromolecular micelles revealed long-term colloidal stability in aqueous medium, with a nearly neutral negative surface charge and mean hydrodynamic diameter in the range 100–400 nm, depending on the polymer degree of substitution. Good size stability was observed when nanogels were exposed to potential destabilizing pH conditions. While the size stability of the nanogel made of pullulan with vinyl methacrylate and more hydrophobic chains grafted was affected by the ionic strength and urea, nanogel made of pullulan with hydroxyethyl methacrylate and fewer hydrophobic chains grafted remained stable.

Development of chitosan-pullulan composite nanoparticles for nasal delivery of vaccines: in vivo studies.

Science.gov (United States)

Cevher, Erdal; Salomon, Stefan K; Somavarapu, Satyanarayana; Brocchini, Steve; Alpar, H Oya

2015-01-01

Here, we aimed at developing chitosan/pullulan composite nanoparticles and testing their potential as novel systems for the nasal delivery of diphtheria toxoid (DT). All the chitosan derivatives [N-trimethyl (TMC), chloride and glutamate] and carboxymethyl pullulan (CMP) were synthesised and antigen-loaded composites were prepared by polyion complexation of chitosan and pullulan derivatives (particle size: 239-405 nm; surface charge: +18 and +27 mV). Their immunological effects after intranasal administration to mice were compared to intramuscular route. Composite nanoparticles induced higher levels of IgG responses than particles formed with chitosan derivative and antigen. Nasally administered TMC-pullulan composites showed higher DT serum IgG titre when compared with the other composites. Co-encapsulation of CpG ODN within TMC-CMP-DT nanoparticles resulted in a balanced Th1/Th2 response. TMC/pullulan composite nanoparticles also induced highest cytokine levels compared to those of chitosan salts. These findings demonstrated that TMC-CMP-DT composite nanoparticles are promising delivery system for nasal vaccination.

Preactivated thiolated pullulan as a versatile excipient for mucosal drug targeting.

Science.gov (United States)

Leonaviciute, Gintare; Suchaoin, Wongsakorn; Matuszczak, Barbara; Lam, Hung Thanh; Mahmood, Arshad; Bernkop-Schnürch, Andreas

2016-10-20

The purpose of the present study was to generate a novel mucoadhesive thiolated pullulan with protected thiol moieties and to evaluate its suitability as mucosal drug delivery system. Two different synthetic pathways: bromination-nucleophilic substitution and reductive amination including periodate cleavage were utilized to synthesize such thiolated pullulans. The thiomer (pullulan-cysteamine) with the highest amount of free thiol groups was further enrolled in a reaction with 6-mercaptonicotinamide and its presence in pullulan structure was confirmed via NMR analysis. Furthermore, unmodified, thiolated and preactivated thiolated pullulan were investigated in terms of mucoadhesion via rotating cylinder studies and rheological synergism method as well as their toxicity potential over Caco-2 cells. Comparing both methods the reductive amination seems to be the method of choice resulting in comparatively higher coupling rates. Using this procedure pullulan-cysteamine conjugate displayed 1522±158μmol immobilized thiol groups and 280±70μmol free thiol groups per gram polymer. Furthermore, 82% of free thiol groups on this conjugate were linked with 6-mercaptonicotinamide (6-MNA). The adhesion time on the rotating cylinder was up to 46-fold prolonged in case of the thiolated polymer and up to 75-fold in case of the preactivated polymer. Rheological measurements of modified pullulan samples showed 98-fold and 160-fold increase in dynamic viscosity upon the addition of mucus within 60min, whereas unmodified pullulan did not show an increase in viscosity at all. Both conjugates had a minor effect on Caco-2 cell viability. Because of these features preactivated thiolated pullulan seems to represent a promising type of mucoadhesive polymers for the development of various mucosal drug delivery systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Improvement on Physical Properties of Pullulan Films by Novel Cross-Linking Strategy.

Science.gov (United States)

Chen, Chieh-Ting; Chen, Kuan-I; Chiang, Hsin-Han; Chen, Yu-Kuo; Cheng, Kuan-Chen

2017-01-01

Pullulan based films possess several advantages, including high transparency, low toxicity, good biodegradability, good mechanical properties, and low oxygen permeability, are preferable for food packaging. The application of pullulan films on food packaging, however, has inherent disadvantage of high water solubility. In this study, glutaraldehyde and glycerol were used as the cross-linking reagent and the plasticizer respectively to improve water resistance and physical properties of the pullulan films. Effects of cross-linking degree on physical properties, including water absorptions, swelling behaviors, water vapor permeability and tensile strengths of films were evaluated. FTIR results demonstrated that the pullulan films were successfully cross-linked by glutaraldehyde. The tensile strength of pullulan films could be enhanced significantly (P permeability. © 2016 Institute of Food Technologists®.

47 CFR 32.2311 - Station apparatus.

Science.gov (United States)

2010-10-01

... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2311 Station apparatus... company shall prepare a list of station apparatus which shall be used as its list of disposition units for... technicians, and others, shall be included in Account 2114, Tools and other work equipment, Account 2220...

77 FR 8731 - Aureobasidium pullulans

Science.gov (United States)

2012-02-15

.... Fliessbach, L. Tamm, F.P. Weibel, G.S. Wyss. 2008. Culturable fungi of stored `Golden Delicious' apple fruits... apply to me? You may be potentially affected by this action if you are an agricultural [[Page 8732

African Journal of Clinical and Experimental Microbiology - Vol 6, No ...

African Journals Online (AJOL)

Antistaphylococcal metabolite from Aureobasidium pullulans: production and characterization · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... Opportunistic infections and clinico-epidemiological factors in HIV/AIDS casesseen in a tertiary care hospital in Nepal · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

F-16 Microbially Influenced Corrosion (MIC) Characterization & Prevention Study

Science.gov (United States)

2011-05-12

Staphylococcus epidermidis Fungal Consortium Aspergillus fumigatus Fusarium oxysporum Penicillium oxalicum Rhodoturula sp . Trichoderma sp . Control... sp . (FI-18) – Hypocrea jecorina (FI-1) Penicillium oxalicum (FI-12) – Pleosporacea sp . (FI-17) Rhodoturala mucilaginosa (FI-7) – Ustilago maydis (FI...Growth, or Soil and Dirt Accumulation • Fungal Consortium – Aspergillus sp (FI-19) Aureobasidium pullulans (FI-16) – Fusarium oxysporum (FI-6) Fusarium

Optimization of fast disintegration tablets using pullulan as diluent by central composite experimental design

OpenAIRE

Patel, Dipil; Chauhan, Musharraf; Patel, Ravi; Patel, Jayvadan

2012-01-01

The objective of this work was to apply central composite experimental design to investigate main and interaction effect of formulation parameters in optimizing novel fast disintegration tablets formulation using pullulan as diluents. Face centered central composite experimental design was employed to optimize fast disintegration tablet formulation. The variables studied were concentration of diluents (pullulan, X1), superdisintigrant (sodium starch glycolate, X2), and direct compression aid ...

Augmented liver targeting of exosomes by surface modification with cationized pullulan.

Science.gov (United States)

Tamura, Ryo; Uemoto, Shinji; Tabata, Yasuhiko

2017-07-15

Exosomes are membrane nanoparticles containing biological substances that are employed as therapeutics in experimental inflammatory models. Surface modification of exosomes for better tissue targetability and enhancement of their therapeutic ability was recently attempted mainly using gene transfection techniques. Here, we show for the first time that the surface modification of exosomes with cationized pullulan, which has the ability to target hepatocyte asialoglycoprotein receptors, can target injured liver and enhance the therapeutic effect of exosomes. Surface modification can be achieved by a simple mixing of original exosomes and cationized pullulan and through an electrostatic interaction of both substances. The exosomes modified with cationized pullulan were internalized into HepG2 cells in vitro to a significantly greater extent than unmodified ones and this internalization was induced through the asialoglycoprotein receptor that was specifically expressed on HepG2 cells and hepatocytes. When injected intravenously into mice with concanavalin A-induced liver injury, the modified exosomes accumulated in the liver tissue, resulting in an enhanced anti-inflammatory effect in vivo. It is concluded that the surface modification with cationized pullulan promoted accumulation of the exosomes in the liver and the subsequent biological function, resulting in a greater therapeutic effect on liver injury. Exosomes have shown potentials as therapeutics for various inflammatory disease models. This study is the first to show the specific accumulation of exosomes in the liver and enhanced anti-inflammatory effect via the surface modification of exosomes using pullulan, which is specifically recognized by the asialoglycoprotein receptor (AGPR) on HepG2 cells and hepatocytes. The pullulan was expressed on the surface of PKH-labeled exosomes, and it led increased accumulation of PKH into HepG2 cells, whereas the accumulation was canceled by AGPR inhibitor. In the mouse

Pullulan as a potent green inhibitor for corrosion mitigation of aluminum composite: Electrochemical and surface studies.

Science.gov (United States)

B P, Charitha; Rao, Padmalatha

2018-06-01

This work emphasizes the corrosion inhibition ability of pullulan, an environmentally benign fungal polysaccharide on acid corrosion of 6061Aluminum-15% (v) SiC (P) composite material (Al-CM). The electrochemical measurements such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) studies were carried out for the corrosion inhibition studies. Conditions were optimized to obtain maximum inhibition efficiency, by performing the experiment at varying concentrations of inhibitor, in the temperature range of 308K- 323K. Surface morphology studies were done to reaffirm the adsorption of inhibitor on the surface of composite material. Pullulan acted as mixed type of inhibitor with a maximum efficiency of 89% at 303K for the addition of 1.0 gL -1 of inhibitor. Evaluation of kinetic and thermodynamic parameters revealed that inhibitor underwent physical adsorption onto the surface of Al-CM and obeyed Freundlich adsorption isotherm. The surface characterization like SEM-EDX, AFM confirmed the adsorption of pullulan molecule. Pullulan can be considered as effective, eco friendly green inhibitor for the corrosion control of Al-CM. Copyright © 2018 Elsevier B.V. All rights reserved.

Microbial Influenced Corrosion (MIC) Study

Science.gov (United States)

2012-05-23

fumigatus Fusarium oxysporum Fungal Consortium Penicillium oxalicum Rhodoturula sp . Trichoderma sp . Dosed with microbes known to influence Control...Hypocrea jecorina (FI-1) Penicillium oxalicum (FI-12) – Pleosporacea sp . (FI-17) Rhodoturala mucilaginosa (FI-7) – Ustilago maydis (FI-13) T t S t• es...and Dirt Accumulation • Fungal Consortium – Aspergillus sp (FI-19) Aureobasidium pullulans (FI-16) – Fusarium oxysporum (FI-6) Fusarium sp . (FI-18

Deoiledjatropha seed cake is a useful nutrient for pullulan production

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Choudhury Anirban

2012-03-01

Full Text Available Abstract Background Ever increasing demand for fossil fuels is a major factor for rapid depletion of these non-renewable energy resources, which has enhanced the interest of finding out alternative sources of energy. In recent years jatropha seed oil has been used extensively for production of bio-diesel and has shown significant potential to replace petroleum fuels at least partially. De-oiled jatropha seed cake (DOJSC which comprises of approximately 55 to 65% of the biomass is a byproduct of bio-diesel industry. DOJSC contains toxic components like phorbol esters which restricts its utilization as animal feed. Thus along with the enhancement of biodiesel production from jatropha, there is an associated problem of handling this toxic byproduct. Utilization of DOJSC as a feed stock for production of biochemicals may be an attractive solution to the problem. Pullulan is an industrially important polysaccharide with several potential applications in food, pharmaceuticals and cosmetic industries. However, the major bottleneck for commercial utilization of pullulan is its high cost. A cost effective process for pullulan production may be developed using DOJSC as sole nutrient source which will in turn also help in utilization of the byproduct of bio-diesel industry. Results In the present study, DOJSC has been used as a nutrient for production of pullulan, in place of conventional nutrients like yeast extract and peptone. Process optimization was done in shake flasks, and under optimized conditions (8% DOJSC, 15% dextrose, 28°C temperature, 200 rpm, 5% inoculum, 6.0 pH 83.98 g/L pullulan was obtained. The process was further validated in a 5 L laboratory scale fermenter. Conclusion This is the first report of using DOJSC as nutrient for production of an exopolysaccharide. Successful use of DOJSC as nutrient will help in finding significant application of this toxic byproduct of biodiesel industry. This in turn also have a significant impact on

Affect the Cross Linking Degree and Polymer Composition on the Mechanical Properties of Poly (vinyl alcohol/ Pullu-lan Films

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Shemaa Abdul Satar Soud

2018-04-01

Full Text Available In this study Cross-linked PVA/Pullulan film was prepared. Cross-linking reaction done by addi-tion of gluteraldehyde at different reaction time (10,30and 60 min. Chemical interaction, me-chanical, thermal properties, water solubility and film morphology was studied for cross-linked PVA/Pullulan, PVA and Pullulan only. Thus FTIR investigated formation of hydrogen bonding between pullulan and PVA with (GA. Tensile strength, tensile modulus and elongation (% at break for PVA/Pullulan film was improved with addition of (GA as the reaction time proceed equivalent with increasing PVA content

Incorporation of Rutin in Electrospun Pullulan/PVA Nanofibers for Novel UV-Resistant Properties.

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Qian, Yongfang; Qi, Mengjie; Zheng, Laijiu; King, Martin W; Lv, Lihua; Ye, Fang

2016-06-23

This study aimed to investigate the incorporation of rutin into electrospun pullulan and poly(vinyl alcohol) (PVA) nanofibers to obtain ultraviolet (UV)-resistant properties. The effect of weight ratios between pullulan and PVA, and the addition of rutin on the nanofibers' morphology and diameters were studied and characterized by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) analysis was utilized to investigate the interaction between pullulan and PVA, as well as with rutin. The results showed that the inclusion of PVA results in the increase in the fiber's diameter. The addition of rutin had no obvious effect on the fibers' average diameters when the content of rutin was less than 7.41%. FTIR results indicated that a hydrogen bond formed between pullulan and PVA, also between these polymers and rutin. Moreover, the addition of rutin could enhance the mechanical properties due to its stiff structure and could decrease the transmittance of UVA and UVB to be fewer than 5%; meanwhile, the value of ultraviolet protection factor (UPF) reached more than 40 and 50 when the content of rutin was 4.46% and 5.67%, respectively. Therefore, the electrospun pullulan/PVA/rutin nanofibrous mats showed excellent UV resistance and have potential applications in anti-ultraviolet packaging and dressing materials.

Statement of Basis/Proposed Plan for the F-Area Burning/Rubble Pits (231-F, 231-1F, and 231-2F)

International Nuclear Information System (INIS)

Palmer, E.

1996-08-01

The purpose of this source unit Statement of Basis/Proposed Plan is to describe the preferred alternative for addressing the F-Area Burning/Rubble Pits (231-F and 231-1F) and Rubble Pit (231-2F) (FBRP) source unit located at SRS, in southwestern Aiken County, South Carolina and to provide an opportunity for public input into the remedial action selection process

Childhood hypersensitivity pneumonitis associated with fungal contamination of indoor hydroponics.

Science.gov (United States)

Engelhart, Steffen; Rietschel, Ernst; Exner, Martin; Lange, Lars

2009-01-01

Childhood hypersensitivity pneumonitis (HP) is often associated with exposure to antigens in the home environment. We describe a case of HP associated with indoor hydroponics in a 14-year-old girl. Water samples from hydroponics revealed Aureobasidium pullulans as the dominant fungal micro-organism (10(4)CFU/ml). The diagnosis is supported by the existence of serum precipitating antibodies against A. pullulans, lymphocytic alveolitis on bronchoalveolar lavage (BAL) fluid, a corresponding reaction on a lung biopsy, and the sustained absence of clinical symptoms following the removal of hydroponics from the home. We conclude that hydroponics should be considered as potential sources of fungal contaminants when checking for indoor health complaints.

JPRS Report Science & Technology USSR: Life Sciences

Science.gov (United States)

1990-06-18

Fractionated Irradiation [V. N. Malakhovskiy, M. I. Bokk; RADIOBIOLOGIYA, Vol 29 No 3, May-Jun 89] 41 Melanin Acts as Radioprotector [A. Patyko...Alternaria alternata, Aureobasidium pullulans, Tricho- derma viride; but Aspergillus niger, Cladosporium her- barum, Stemphylium ilicis, and Ulocladium atrum...of the above. Melanin -producing micromycetes predominated on materials subjected to storage both in open fields and sheds. Determinations of

Functional Biomaterials: Solution Electrospinning and Gelation of Whey Protein and Pullulan

Science.gov (United States)

Sullivan, Stephanie Tolstedt

Utilizing biomaterials that are biodegradable, biocompatible and edible serve well for food products as well as biomedical applications. Biomaterials whey protein and pullulan both have these characteristics. Whey proteins (WP) have been used in food products for many years and more recently in pharmaceutical products. They have the ability to form both gels and stable foams. Pullulan (PULL) has also been used in both food and pharmaceutical products, and is a highly water soluble, non-gelling polysaccharide and has been used primarily as a film former. Herein, we investigate the ability of whey protein and pullulan to form nanofibers and gels. Combining their distinct properties allows the ability to uniquely manipulate nanofiber and gel characteristics and behavior for a variety of applications, from food to even tissue scaffolding. First, we determined the electrospinnability of aqueous whey protein solutions. Both whey protein isolate (WPI) and one of its major components beta--lactoglobulin (BLG), either in native or denatured form, yielded interesting micro and nanostructures when electrosprayed; while nanofiber production required blending with a spinnable polymer, poly(ethylene oxide) (PEO). WP:PEO solutions were also successfully electrospun at acidic pH (2≤pH≤3), which could improve shelf life. Fourier Transform Infrared Reflectance (FTIR) analysis of WP:PEO fiber mat indicated some variation in WP secondary structure with varying WPI concentration (as WPI increased, % alpha-helix increased and beta-turn decreased) and pH (as pH decreased from neutral (7.5) to acidic (2), % beta-sheet decreased and alpha-helix increased). X-ray Photoelectron Spectroscopy (XPS) also confirmed the presence of WP on the surface of the blend fibers, augmenting the FTIR analysis. Interestingly, WP:PEO composite nanofibers maintained its fibrous morphology at temperatures as high as 100 °C, above the 60 °C PEO melting point. Further, we show that the blend mats retained a

Pullulan-based composite scaffolds for bone tissue engineering: Improved osteoconductivity by pore wall mineralization.

Science.gov (United States)

Amrita; Arora, Aditya; Sharma, Poonam; Katti, Dhirendra S

2015-06-05

Porous hydrogels have been explored for bone tissue engineering; however their poor mechanical properties make them less suitable as bone graft substitutes. Since incorporation of fillers is a well-accepted method for improving mechanical properties of hydrogels, in this work pullulan hydrogels were reinforced with nano-crystalline hydroxyapatite (nHAp) (5 wt% nHAp in hydrogel) and poly(3-hydroxybutyrate) (PHB) fibers (3 wt% fibers in hydrogel) containing nHAp (3 wt% nHAp in fibers). Addition of these fillers to pullulan hydrogel improved compressive modulus of the scaffold by 10 fold. However, the hydrophilicity of pullulan did not support adhesion and spreading of cells. To overcome this limitation, porous composite scaffolds were modified using a double diffusion method that enabled deposition of hydroxyapatite on pore walls. This method resulted in rapid and uniform coating of HAp throughout the three-dimensional scaffolds which not only rendered them osteoconductive in vitro but also led to an improvement in their compressive modulus. These results demonstrate the potential of mineralized pullulan-based composite scaffolds in non-load bearing bone tissue engineering. Copyright © 2015 Elsevier Ltd. All rights reserved.

Antimicrobial activity of berberine--a constituent of Mahonia aquifolium.

Science.gov (United States)

Cernáková, M; Kostálová, D

2002-01-01

The antimicrobial activity of the protoberberine alkaloid, berberine, isolated from Mahonia aquifolium, was evaluated against 17 microorganisms including two Gram-negative bacteria--Pseudomonas aeruginosa and Escherichia coli (both resistant and sensitive), two Gram-positive bacteria--Bacillus subtilis and Staphylococcus aureus, Zoogloea ramigera, six filamentous fungi--Penicilium chrysogenum, Aspergillus niger, Aureobasidium pullulans (black and white strain), Trichoderma viride (original green strain and brown mutant), Fusarium nivale, Mycrosporum gypseum and two yeasts--Candida albicans and Saccharomyces cerevisiae. The IC50, minimum inhibitory concentration (MIC), minimum microbicidal concentration (MMC) and minimum microbistatic concentration (MMS) varied considerably depending on the microorganism tested, the sensitivity decreasing as follows: S. aureus > P. aeruginosa S (sensitive) > E. coli S > P. aeruginosa R (resistant) > E. coli R > B. subtilis > Z. ramigera > C. albicans > S. cerevisiae > A. pullulans B (black) > A. pullulans W (white) > T. viride Br (brown) > M. gypseum > A. niger > F. nivale > P. chrysogenum > T. viride G (green).

Efficacy of antimicrobial pullulan-based coating to improve internal quality and shelf-life of chicken eggs during storage.

Science.gov (United States)

Morsy, Mohamed K; Sharoba, Ashraf M; Khalaf, Hassan H; El-Tanahy, Hassan H; Cutter, Catherine N

2015-05-01

There has been a growing interest in the use of natural materials as a delivery mechanism for antimicrobials and coatings in foods. The aim of the present study was to evaluate the effectiveness of pullulan coatings to improve internal quality and shelf-life of fresh eggs during 10 wk of storage at 25 and 4 °C. Three treatments of eggs were evaluated as follows; non-coated (control; C), coated with pullulan (P), and coated with pullulan containing nisin (N). The effects of the pullulan coatings on microbiological qualities, physical properties, and freshness parameters were investigated and compared with non-coated eggs. For non-coated eggs, as storage time increased, yolk index, albumen index, and Haugh unit value decreased and weight loss increased. However, pullulan coatings (P or N) minimized weight loss (eggs (with a final B grade) 3 wk longer than non-coated eggs at 25 °C. At 4 °C, both P- and N-coated eggs went from AA to A grade after 9 wk and maintained the grade for 10 wk (4 wk longer than that of non-coated eggs). This study is the first to demonstrate that pullulan coatings can preserve the internal quality, prolong the shelf-life, and minimize weight loss of fresh eggs. © 2015 Institute of Food Technologists®

Cellularized Bilayer Pullulan-Gelatin Hydrogel for Skin Regeneration.

Science.gov (United States)

Nicholas, Mathew N; Jeschke, Marc G; Amini-Nik, Saeid

2016-05-01

Skin substitutes significantly reduce the morbidity and mortality of patients with burn injuries and chronic wounds. However, current skin substitutes have disadvantages related to high costs and inadequate skin regeneration due to highly inflammatory wounds. Thus, new skin substitutes are needed. By combining two polymers, pullulan, an inexpensive polysaccharide with antioxidant properties, and gelatin, a derivative of collagen with high water absorbency, we created a novel inexpensive hydrogel-named PG-1 for "pullulan-gelatin first generation hydrogel"-suitable for skin substitutes. After incorporating human fibroblasts and keratinocytes onto PG-1 using centrifugation over 5 days, we created a cellularized bilayer skin substitute. Cellularized PG-1 was compared to acellular PG-1 and no hydrogel (control) in vivo in a mouse excisional skin biopsy model using newly developed dome inserts to house the skin substitutes and prevent mouse skin contraction during wound healing. PG-1 had an average pore size of 61.69 μm with an ideal elastic modulus, swelling behavior, and biodegradability for use as a hydrogel for skin substitutes. Excellent skin cell viability, proliferation, differentiation, and morphology were visualized through live/dead assays, 5-bromo-2'-deoxyuridine proliferation assays, and confocal microscopy. Trichrome and immunohistochemical staining of excisional wounds treated with the cellularized skin substitute revealed thicker newly formed skin with a higher proportion of actively proliferating cells and incorporation of human cells compared to acellular PG-1 or control. Excisional wounds treated with acellular or cellularized hydrogels showed significantly less macrophage infiltration and increased angiogenesis 14 days post skin biopsy compared to control. These results show that PG-1 has ideal mechanical characteristics and allows ideal cellular characteristics. In vivo evidence suggests that cellularized PG-1 promotes skin regeneration and may

Yeasts and yeast-like organisms associated with fruits and blossoms of different fruit trees.

Science.gov (United States)

Vadkertiová, Renáta; Molnárová, Jana; Vránová, Dana; Sláviková, Elena

2012-12-01

Yeasts are common inhabitants of the phyllosphere, but our knowledge of their diversity in various plant organs is still limited. This study focused on the diversity of yeasts and yeast-like organisms associated with matured fruits and fully open blossoms of apple, plum, and pear trees, during 2 consecutive years at 3 localities in southwest Slovakia. The occurrence of yeasts and yeast-like organisms in fruit samples was 2½ times higher and the yeast community more diverse than that in blossom samples. Only 2 species (Aureobasidium pullulans and Metschnikowia pulcherrima) occurred regularly in the blossom samples, whereas Galactomyces candidus, Hanseniaspora guilliermondii, Hanseniaspora uvarum, M. pulcherrima, Pichia kluyveri, Pichia kudriavzevii, and Saccharomyces cerevisiae were the most frequently isolated species from the fruit samples. The ratio of the number of samples where only individual species were present to the number of samples where 2 or more species were found (consortium) was counted. The occurrence of individual species in comparison with consortia was much higher in blossom samples than in fruit samples. In the latter, consortia predominated. Aureobasidium pullulans, M. pulcherrima, and S. cerevisiae, isolated from both the fruits and blossoms, can be considered as resident yeast species of various fruit tree species cultivated in southwest Slovakia localities.

Deep optical survey of the stellar content of Sh2-311 region

Science.gov (United States)

Yadav, Ram Kesh; Pandey, A. K.; Sharma, Saurabh; Jose, J.; Ogura, K.; Kobayashi, N.; Samal, M. R.; Eswaraiah, C.; Chandola, H. C.

2015-01-01

The stellar content in and around Sh2-311 region have been studied using the deep optical observations as well as near-infrared (NIR) data from 2MASS. The region contains three clusters, viz. NGC 2467, Haffner 18 and Haffner 19. We have made an attempt to distinguish the stellar content of these individual regions as well as to re-determine their fundamental parameters such as distance, reddening, age, onto the basis of a new and more extended optical and infrared photometric data set. NGC 2467 and Haffner 19 are found to be located in the Perseus arm at the distances of 5.0 ± 0.4 kpc and 5.7 ± 0.4 kpc, respectively, whereas Haffner 18 is located at the distance of 11.2 ± 1.0 kpc. The clusters NGC 2467 and Haffner 19 might have formed from the same molecular cloud, whereas the cluster Haffner 18 is located in the outer galactic arm, i.e. the Norma-Cygnus arm. We identify 8 class II young stellar objects (YSOs) using the NIR (J-H)/(H-K) two colour diagram. We have estimated the age and mass of the YSOs identified in the present work and those by Snider et al. (2009) using the V/(V-I) colour-magnitude diagram. The estimated ages and mass range of the majority of the YSOs are ≲1 Myr and ∼0.4-3.5 M⊙, respectively, indicating that these sources could be T-Tauri stars or their siblings. Spatial distribution of the YSOs shows that some of the YSOs are distributed around the HII region Sh2-311, suggesting a triggered star formation at its periphery.

Effect of pullulan nanoparticle surface charges on HSA complexation and drug release behavior of HSA-bound nanoparticles.

Directory of Open Access Journals (Sweden)

Xiaojun Tao

Full Text Available Nanoparticle (NP compositions such as hydrophobicity and surface charge are vital to determine the presence and amount of human serum albumin (HSA binding. The HSA binding influences drug release, biocompatibility, biodistribution, and intercellular trafficking of nanoparticles (NPs. Here, we prepared 2 kinds of nanomaterials to investigate HSA binding and evaluated drug release of HSA-bound NPs. Polysaccharides (pullulan carboxyethylated to provide ionic derivatives were then conjugated to cholesterol groups to obtain cholesterol-modified carboxyethyl pullulan (CHCP. Cholesterol-modified pullulan (CHP conjugate was synthesized with a similar degree of substitution of cholesterol moiety to CHCP. CHCP formed self-aggregated NPs in aqueous solution with a spherical structure and zeta potential of -19.9 ± 0.23 mV, in contrast to -1.21 ± 0.12 mV of CHP NPs. NPs could quench albumin fluorescence intensity with maximum emission intensity gradually decreasing up to a plateau at 9 to 12 h. Binding constants were 1.12 × 10(5 M(-1 and 0.70 × 10(5 M(-1 to CHP and CHCP, respectively, as determined by Stern-Volmer analysis. The complexation between HSA and NPs was a gradual process driven by hydrophobic force and inhibited by NP surface charge and shell-core structure. HSA conformation was altered by NPs with reduction of α-helical content, depending on interaction time and particle surface charges. These NPs could represent a sustained release carrier for mitoxantrone in vitro, and the bound HSA assisted in enhancing sustained drug release.

Volatile emissions from an epiphytic fungus are semiochemicals for eusocial wasps.

Science.gov (United States)

Davis, Thomas Seth; Boundy-Mills, Kyria; Landolt, Peter J

2012-11-01

Microbes are ubiquitous on plant surfaces. However, interactions between epiphytic microbes and arthropods are rarely considered as a factor that affects arthropod behaviors. Here, volatile emissions from an epiphytic fungus were investigated as semiochemical attractants for two eusocial wasps. The fungus Aureobasidium pullulans was isolated from apples, and the volatile compounds emitted by fungal colonies were quantified. The attractiveness of fungal colonies and fungal volatiles to social wasps (Vespula spp.) were experimentally tested in the field. Three important findings emerged: (1) traps baited with A. pullulans caught 2750 % more wasps on average than unbaited control traps; (2) the major headspace volatiles emitted by A. pullulans were 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-phenylethyl alcohol; and (3) a synthetic blend of fungal volatiles attracted 4,933 % more wasps on average than unbaited controls. Wasps were most attracted to 2-methyl-1-butanol. The primary wasp species attracted to fungal volatiles were the western yellowjacket (Vespula pensylvanica) and the German yellowjacket (V. germanica), and both species externally vectored A. pullulans. This is the first study to link microbial volatile emissions with eusocial wasp behaviors, and these experiments indicate that volatile compounds emitted by an epiphytic fungus can be responsible for wasp attraction. This work implicates epiphytic microbes as important components in the community ecology of some eusocial hymenopterans, and fungal emissions may signal suitable nutrient sources to foraging wasps. Our experiments are suggestive of a potential symbiosis, but additional studies are needed to determine if eusocial wasp-fungal associations are widespread, and whether these associations are incidental, facultative, or obligate.

Screening of micro-organisms for decolorization of melanins produced by bluestain fungi.

Science.gov (United States)

Rättö, M; Chatani, M; Ritschkoff, A C; Viikari, L

2001-03-01

A total of 17 fungi and four bacteria were screened for their ability to decolorize melanin, using isolated extracellular melanin of the bluestain fungus Aureobasidium pullulans as substrate. On agar media, decolorization was observed by four fungal strains: Bjerkandera adusta VTT-D-99746, Galactomyces geotrichum VTT-D-84228, Trametes hirsuta VTT-D-95443 and Trametes versicolor VTT-D-99747. The four fungi were more efficient on nitrogen-limited medium than on complete medium. The melanin-decolorizing activity of G. geotrichum appeared to be located on the mycelium and could be liberated into the medium enzymatically.

Role of Pullulan in preparation of ceria nanoparticles and investigation of their biological activities

Science.gov (United States)

Khorrami, Mohammad Bagher; Sadeghnia, Hamid Reza; Pasdar, Alireza; Ghayour-Mobarhan, Majid; Riahi-Zanjani, Bamdad; Darroudi, Majid

2018-04-01

Throughout this work, a facile, environmental-friendly, and "green" method is delineated for preparing ceria nanoparticles (CNPs), which utilizes nontoxic and renewable degraded polysaccharide polymer including pullulan as a natural matrix. Pullulan behaves as a suitable stabilizing (capping) agent for CNPs that are effectively formed at various high temperatures, while they are structurally analyzed through different techniques such as TGA/DTG, XRD, FESEM, and FTIR instruments. This procedure was found to be comparable to the ones that were acquired from conventional preparation methods that employ hazardous materials, which confirms this approach to be an exquisite alternative in preparing CNPs through the benefit of bioorganic materials. The in vitro cytotoxicity studies on Neuro2A cells have mentioned nontoxic particles in a range of concentrations (0.97-125 μg/ml) and thus, we reckon that the prepared particular CNPs will have persistent utilization in various fields of biology and medicine.

Microfibrillated cellulose and borax as mechanical, O₂-barrier, and surface-modulating agents of pullulan biocomposite coatings on BOPP.

Science.gov (United States)

Cozzolino, Carlo A; Campanella, Gaetano; Türe, Hasan; Olsson, Richard T; Farris, Stefano

2016-06-05

Multifunctional composite coatings on bi-oriented polypropylene (BOPP) films were obtained using borax and microfibrillated cellulose (MFC) added to the main pullulan coating polymer. Spectroscopy analyses suggested that a first type of interaction occurred via hydrogen bonding between the C6OH group of pullulan and the hydroxyl groups of boric acid, while monodiol and didiol complexation represented a second mechanism. The deposition of the coatings yielded an increase in the elastic modulus of the entire plastic substrate (from ∼2GPa of the neat BOPP to ∼3.1GPa of the P/B+/MFC-coated BOPP). The addition of MFC yielded a decrease of both static and kinetic coefficients of friction of approximately 22% and 25%, respectively, as compared to the neat BOPP. All composite coatings dramatically increased the oxygen barrier performance of BOPP, especially under dry conditions. The deposition of the high hydrophilic coatings allowed to obtain highly wettable surfaces (water contact angle of ∼18°). Copyright © 2016 Elsevier Ltd. All rights reserved.

Oxidative stability of pullulan nanofibers loaded with fish oil: effect of oil content and antioxidants addition

DEFF Research Database (Denmark)

García Moreno, Pedro Jesús; Damberg, C.; Stephansen, K.

Electrospinning processing is a promising technique for the encapsulation of thermolabile bioactive compounds (e.g. fish oil) since it does not require the use of heat. Furthermore, the nano-microfibers (NMF) obtained present a reduced size, which makes them easier to disperse in food matrices...... compared to traditional encapsulates (e.g. microcapsules produced by spray-drying). Biopolymers such as proteins and polysaccharides are required for the production of food-grade NMF. In this sense, pullulan, which is a food-approved polysaccharide, is an interesting encapsulating material due to its high...... electrospinnability and low oxygen permeability. In light of the above, the aim of this work was to investigate the oxidative stability of omega-3 enriched pullulan NMF. First, the influence of fish oil content (10-20-30 %) on the properties of the electrospinning solutions (e.g. viscosity, conductivity and surface...

Coating with spermine-pullulan polymer enhances adenoviral transduction of mesenchymal stem cells

Directory of Open Access Journals (Sweden)

Wan L

2016-12-01

Full Text Available Li Wan,1,* Xinglei Yao,1–3,* Francesco Faiola,3 Bojun Liu,4 Tianyuan Zhang,2 Yasuhiko Tabata,5 Hiroyuki Mizuguchi,6 Shinsaku Nakagawa,7 Jian-Qing Gao,2 Robert Chunhua Zhao1 1Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Peking Union Medical College Hospital, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing, 2Institute of Pharmaceutics, Zhejiang University, Hangzhou, 3State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 4YouAn Hospital, Capital Medical University, Beijing, People’s Republic of China; 5Department of Biomaterials, Field of Tissue Engineering, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, 6Department of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, 7Department of Biotechnology and Therapeutics, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan *These authors contributed equally to this work Abstract: Mesenchymal stem cells (MSCs are adult stem cells with multilineage potential, which makes them attractive tools for regenerative medicine applications. Efficient gene transfer into MSCs is essential not only for basic research in developmental biology but also for therapeutic applications involving gene-modification in regenerative medicine. Adenovirus vectors (Advs can efficiently and transiently introduce an exogenous gene into many cell types via their primary receptors, the coxsackievirus and adenovirus receptors, but not into MSCs, which are deficient in coxsackievirus and adenovirus receptors expression. To overcome this problem, we developed an Adv coated with a spermine-pullulan (SP cationic polymer and investigated its physicochemical properties and internalization mechanisms. We demonstrated that the SP

An Injectable Enzymatically Crosslinked Carboxymethylated Pullulan/Chondroitin Sulfate Hydrogel for Cartilage Tissue Engineering

Science.gov (United States)

Chen, Feng; Yu, Songrui; Liu, Bing; Ni, Yunzhou; Yu, Chunyang; Su, Yue; Zhu, Xinyuan; Yu, Xiaowei; Zhou, Yongfeng; Yan, Deyue

2016-01-01

In this study, an enzymatically cross-linked injectable and biodegradable hydrogel system comprising carboxymethyl pullulan-tyramine (CMP-TA) and chondroitin sulfate-tyramine (CS-TA) conjugates was successfully developed under physiological conditions in the presence of both horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) for cartilage tissue engineering (CTTE). The HRP crosslinking method makes this injectable system feasible, minimally invasive and easily translatable for regenerative medicine applications. The physicochemical properties of the mechanically stable hydrogel system can be modulated by varying the weight ratio and concentration of polymer as well as the concentrations of crosslinking reagents. Additionally, the cellular behaviour of porcine auricular chondrocytes encapsulated into CMP-TA/CS-TA hydrogels demonstrates that the hydrogel system has a good cyto-compatibility. Specifically, compared to the CMP-TA hydrogel, these CMP-TA/CS-TA composite hydrogels have enhanced cell proliferation and increased cartilaginous ECM deposition, which significantly facilitate chondrogenesis. Furthermore, histological analysis indicates that the hydrogel system exhibits acceptable tissue compatibility by using a mouse subcutaneous implantation model. Overall, the novel injectable pullulan/chondroitin sulfate composite hydrogels presented here are expected to be useful biomaterial scaffold for regenerating cartilage tissue.

TEMPO-mediated oxidation of pullulan and influence of ionic strength and linear charge density on the dimensions of the obtained polyelectrolyte chains

NARCIS (Netherlands)

Nooy, A.E.J. de; Besemer, A.C.; Bekkum, H. van; Dijk, J.A.P.P. van; Smit, J.A.M.

1996-01-01

The applied pH during the TEMPO-mediated (2,2,6,6-tetramethylpiperidine-1-oxyl) oxidation of the polysaccharide pullulan has a substantial influence on the molar mass distribution of the products. The least degradation was found in the pH range 9.2-9.7 and especially at higher pH, significant

Tocopheryl pullulan-based self assembling nanomicelles for anti-cancer drug delivery

Energy Technology Data Exchange (ETDEWEB)

Wang, Jingyun, E-mail: wangjingyun67@dlut.edu.cn [School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024 (China); Cui, Shuang [School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024 (China); Bao, Yongming, E-mail: biosci@dlut.edu.cn [School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024 (China); Xing, Jishuang [School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024 (China); Hao, Wenbo [Department of Physics and Chemistry, Heihe University, Heihe 164300 (China)

2014-10-01

Amphiphilic α-tocopherol pullulan polymers (PUTC1, PUTC2, and PUTC3) with different degrees of substitution were synthesized as new carriers for anticancer drugs. The polymers easily self-assembled into nanomicelles through dialysis method. The critical micelle concentrations (CMCs) were 38.0, 8.0, and 4.3 mg/L for PUTC1, PUTC2, and PUTC3, respectively. 10-Hydroxycamptothecin (HCPT) used as a model drug was successfully loaded into the PUTC nanomicelles. Transmission electron microscopy images demonstrated that HCPT-loaded PUTC nanomicelles were almost spherical and had sizes ranging within 171.5–257.8 nm that increased with increased HCPT-loading content, as determined by dynamic laser scattering. The highest encapsulation efficiency of HCPT in PUTC nanomicelles reached 98.3%. The in vitro release of HCPT from PUTC micelles demonstrated sustained release for over 80 h. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assays showed that blank PUTC micelles were nontoxic to normal cells and that the HCPT-loaded PUTC2 nanomicelles showed higher cytotoxicity than the free drug, which was attributed to the enhanced cellular uptake of drug-loaded nanomicelles. Biodistribution experiments showed that PUTC micelles provided an excellent approach to rapid drug transport into cell nuclei. Moreover, the cellular uptake of micelles was found to be an energy-dependent and actin polymerization-associated endocytic process by endocytosis inhibition experiments. These results suggested that PUTC nanomicelles had considerable potential as a drug carrier for drug intracellular delivery in cancer therapy. - Highlights: • Tocopheryl pullulan-based (PUTC) self-assembling nanomicelles were fabricated. • These micelles showed low CMC and dispersed uniformly with regular spherical shape. • High entrapment efficiency and in vitro sustained release of HCPT in PUTC micelles • HCPT–PUTC micelles accumulated in cell nuclei and showed higher anticancer activity. �

Tocopheryl pullulan-based self assembling nanomicelles for anti-cancer drug delivery

International Nuclear Information System (INIS)

Wang, Jingyun; Cui, Shuang; Bao, Yongming; Xing, Jishuang; Hao, Wenbo

2014-01-01

Amphiphilic α-tocopherol pullulan polymers (PUTC1, PUTC2, and PUTC3) with different degrees of substitution were synthesized as new carriers for anticancer drugs. The polymers easily self-assembled into nanomicelles through dialysis method. The critical micelle concentrations (CMCs) were 38.0, 8.0, and 4.3 mg/L for PUTC1, PUTC2, and PUTC3, respectively. 10-Hydroxycamptothecin (HCPT) used as a model drug was successfully loaded into the PUTC nanomicelles. Transmission electron microscopy images demonstrated that HCPT-loaded PUTC nanomicelles were almost spherical and had sizes ranging within 171.5–257.8 nm that increased with increased HCPT-loading content, as determined by dynamic laser scattering. The highest encapsulation efficiency of HCPT in PUTC nanomicelles reached 98.3%. The in vitro release of HCPT from PUTC micelles demonstrated sustained release for over 80 h. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assays showed that blank PUTC micelles were nontoxic to normal cells and that the HCPT-loaded PUTC2 nanomicelles showed higher cytotoxicity than the free drug, which was attributed to the enhanced cellular uptake of drug-loaded nanomicelles. Biodistribution experiments showed that PUTC micelles provided an excellent approach to rapid drug transport into cell nuclei. Moreover, the cellular uptake of micelles was found to be an energy-dependent and actin polymerization-associated endocytic process by endocytosis inhibition experiments. These results suggested that PUTC nanomicelles had considerable potential as a drug carrier for drug intracellular delivery in cancer therapy. - Highlights: • Tocopheryl pullulan-based (PUTC) self-assembling nanomicelles were fabricated. • These micelles showed low CMC and dispersed uniformly with regular spherical shape. • High entrapment efficiency and in vitro sustained release of HCPT in PUTC micelles • HCPT–PUTC micelles accumulated in cell nuclei and showed higher anticancer activity. �

Production, Purification, and Gene Cloning of a β-Fructofuranosidase with a High Inulin-hydrolyzing Activity Produced by a Novel Yeast Aureobasidium sp. P6 Isolated from a Mangrove Ecosystem.

Science.gov (United States)

Jiang, Hong; Ma, Yan; Chi, Zhe; Liu, Guang-Lei; Chi, Zhen-Ming

2016-08-01

After screening of over 300 yeast strains isolated from the mangrove ecosystems, it was found that Aureobasidium sp. P6 strain had the highest inulin-hydrolyzing activity. Under the optimal conditions, this yeast strain produced an inulin-hydrolyzing activity of 30.98 ± 0.8 U/ml after 108 h of a 10-l fermentation. After the purification, a molecular weight of the enzyme which had the inulin-hydrolyzing activity was estimated to be 47.6 kDa, and the purified enzyme could actively hydrolyze both sucrose and inulin and exhibit a transfructosylating activity at 30.0 % sucrose, converting sucrose into fructooligosaccharides (FOS), indicating that the purified enzyme was a β-D-fructofuranosidase. After the full length of a β-D-fructofuranosidase gene (accession number KU308553) was cloned from Aureobasidium sp. P6 strain, a protein deduced from the cloned gene contained the conserved sequences MNDPNGL, RDP, ECP, FS, and Q of a glycosidehydrolase GH32 family, respectively, but did not contain a conserved sequence SVEVF, and the amino acid sequence of the protein from Aureobasidium sp. P6 strain had a high similarity to that of the β-fructofuranosidase from any other fungal strains. After deletion of the β-D-fructofuranosidase gene, the disruptant still had low inulin hydrolyzing and invertase activities and a trace amount of the transfructosylating activity, indicating that the gene encoding an inulinase may exist in the Aureobasidium sp. P6 strain.

Maintenance-energy-dependent dynamics of growth and poly(3-hydroxybutyrate) [P(3HB)] production by Azohydromonas lata MTCC 2311 using simple and renewable carbon substrates

OpenAIRE

Zafar,M.; Kumar,S.; Kumar,S.; Dhiman,A. K.; Park,H.-S.

2014-01-01

The dynamics of microbial growth and poly(3-hydroxybutyrate) [P(3HB)] production in growth/ non-growth phases of Azhohydromonas lata MTCC 2311 were studied using a maintenance-energy-dependent mathematical model. The values of calculated model kinetic parameters were: m s1 = 0.0005 h-1, k = 0.0965, µmax = 0.25 h-1 for glucose; m s1 = 0.003 h-1, k = 0.1229, µmax = 0.27 h-1 for fructose; and m s1 = 0.0076 h-1, k = 0.0694, µmax = 0.25 h-1 for sucrose. The experimental data of biomass growth, sub...

Frecuencia y resistencia bacteriana de Staphylococcus aureus en infecciones nosocomiales en el Hospital Universitario de Caracas, años 2004 y 2007

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Guillermo Borga Hernández

2010-01-01

Full Text Available Objetivo: Determinar la frecuencia de infecciones nosocomiales y resistencia a meticiclina de S. aureus en el Hospital Universitario de Caracas, primer semestre de años 2004 y 2007. Materiales y Métodos: Estudio descriptivo para determinar frecuencia de infecciones intrahospitalarias (IN y resistencia a meticiclina de S. aureus, se analizaron los informes de los Boletines de la Sub Comisión de Infecciones Hospitalarias del Hospital Universitario de Caracas correspondientes al primer semestre de los años 2004 y 2007 Resultados: En el año 2004 se registraron 1.608 casos de IN, 6,84% ocasionadas por S. aureus y 2.311 en el año 2007, 10,42% causadas por dicho microorganismo. La resistencia a la meticilina en el año 2004 fue 14% de las 110 cepas aisladas y en el 2007 fue de 68% de las 241 cepas aisladas. Conclusiones: Existe diferencia en la frecuencia de infecciones hospitalarias producidas por S. aureus y en la resistencia a meticiclina de las cepas en el HUC, mayor en el 2007 en comparación al 2004.

Water-soluble low-molecular-weight -(1, 3–1, 6 D-Glucan inhibit cedar pollinosis

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Tomoko Jippo

2015-02-01

Full Text Available Background: The incidence of allergic diseases such as allergic rhinitis, atopic dermatitis, asthma, and food allergies has increased in several countries. Mast cells have critical roles in various biologic processes related to allergic diseases. Mast cells express the high-affinity receptor for immunoglobulin (Ig E on their surface. The interaction of multivalent antigens with surface-bound IgE causes the secretion of granule-stored mediators, as well as the de novosynthesis of cytokines. Those mediators and cytokines proceed the allergic diseases. We investigated the effects of water-soluble, low-molecular-weight -(1, 3–1, 6 D-glucan isolated from Aureobasidium pullulans 1A1 strain black yeast (LMW--glucan on mast cell-mediated anaphylactic reactions. We reported that LMW--glucan dose-dependently inhibited the degranulation of mast cells. Furthermore, we found that orally administered LMW--glucan inhibited the IgE-mediated passive cutaneous anaphylaxis (PCA reaction in mice. Here, we examined if LMW--glucan had effects on Japanese cedar pollinosis. Findings: In a clinical study, a randomized, single-blind, placebo-controlled, parallel group study in 65 subjects (aged 2262 was performed. This study was undertaken 3 weeks before and until the end of the cedar pollen season. During the study, all subjects consumed one bottle of placebo or LMW--glucan daily and all subjects were required to record allergic symptoms in a diary. The LMW--glucan group had a significantly lower prevalence of sneezing, nose-blowing, tears, and hindrance to the activities of daily living than the placebo group. Conclusions: These results suggested that LMW--glucan could be an effective treatment for allergic diseases

Iodoacetyl-functionalized pullulan: A supplemental enhancer for single-domain antibody-polyclonal antibody sandwich enzyme-linked immunosorbent assay for detection of survivin.

Science.gov (United States)

Matsushita, Takahiko; Arai, Hidenao; Koyama, Tetsuo; Hatano, Ken; Nemoto, Naoto; Matsuoka, Koji

2017-11-01

Survivin, an inhibitor of the apoptosis protein family, is a potent tumor marker for diagnosis and prognosis. The enzyme-linked immunosorbent assay (ELISA) is one of the methods that has been used for detection of survivin. However, ELISA has several disadvantages caused by the use of conventional antibodies, and we have therefore been trying to develop a novel ELISA system using camelid single-domain antibodies (VHHs) as advantageous replacements. Here we report a supplemental approach to improve the VHH-polyclonal antibody sandwich ELISA for survivin detection. Iodoacetyl-functionalized pullulan was synthesized, and its thiol reactivity was characterized by a model reaction with l-cysteine. The thiophilic pullulan was applied to an immunoassay asan additive upon coating of standard assay plates with an anti-survivin VHH fusion protein with C-terminal cysteine. The results showed that the mole ratio of the additive to VHH had a significant effect on the consequent response. Mole ratios of 0.07, 0.7, and 7 led to 90% lower, 15% higher, and 69% lower responses, respectively, than the response of a positive control in which no additive was used. The background levels observed in any additive conditions were as low as that of a negative control lacking both VHH and the additive. These results indicate the applicability of the thiol-reactive pullulan as a response enhancer to VHH-based ELISA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Studium biodegradace polyhydroxyalkanoátů.

OpenAIRE

Wurstová, Agáta

2014-01-01

Diplomová práce je zaměřena na studium biodegradace polyhydroxyalkanoátů, konkrétně polymeru polyhydroxybutyrátu. První část práce se zabývá studiem biodegradace polyhydroxybutyrátu ve formě PHB prášku a PHB fólie pomocí vybraných druhů mikroorganismů z řad bakterií, kvasinek a plísní. Jako zástupce bakterií byl vybrán mikroorganismus Delftia acidovorans, z řad kvasinek Aureobasidium pullulans a ze zástupců plísní Aspergillus fumigatus. Aktivita extracelulární PHB depolymerázy byla analyzován...

Both a PKS and a PPTase are involved in melanin biosynthesis and regulation of Aureobasidium melanogenum XJ5-1 isolated from the Taklimakan desert.

Science.gov (United States)

Jiang, Hong; Liu, Guang-Lei; Chi, Zhe; Wang, Jian-Ming; Zhang, Ly-Ly; Chi, Zhen-Ming

2017-02-20

A PKS1 gene responsible for the melanin biosynthesis and a NPG1 gene in Aureobasidium melanogenum XJ5-1 were cloned and characterized. An ORF of the PKS1 gene encoding a protein with 2165 amino acids contained 6495bp while an ORF of the NPG1 gene encoding a protein with 340 amino acids had 1076bp. After analysis of their promoters, it was found that expression of both the PKS1 gene and the NPG1 gene was repressed by nitrogen sources and glucose, respectively. The PKS deduced from the cloned gene consisted of one ketosynthase, one acyl transferase, two acyl carrier proteins, one thioesterase and one cyclase while the PPTase belonged to the family Sfp-type. After disruption of the PKS1 gene and the NPG1 gene, expression of the PKS1 gene and the NPG1 gene and the melanin biosynthesis in the disruptants K5 and DP107 disappeared and expression of the PKS1 gene in the disruptant DP107 was also negatively influenced. However, after the NPG1 gene was complemented in the disruptant DP107, the melanin biosynthesis in the complementary strain BP17 was restored and expression of the PKS1 gene and the NPG1 gene was greatly enhanced, suggesting that the PKS was indeed activated and regulated by the PPTase and expression of the PKS1 gene and the NPG1 gene had a coordinate regulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Biocontrol ability and action mechanism of food-isolated yeast strains against Botrytis cinerea causing post-harvest bunch rot of table grape.

Science.gov (United States)

Parafati, Lucia; Vitale, Alessandro; Restuccia, Cristina; Cirvilleri, Gabriella

2015-05-01

Strains belonging to the species Saccharomyces cerevisiae, Wickerhamomyces anomalus, Metschnikowia pulcherrima and Aureobasidium pullulans, isolated from different food sources, were tested in vitro as biocontrol agents (BCAs) against the post-harvest pathogenic mold Botrytis cinerea. All yeast strains demonstrated antifungal activity at different levels depending on species and medium. Killer strains of W. anomalus and S. cerevisiae showed the highest biocontrol in vitro activity, as demonstrated by largest inhibition halos. The competition for iron and the ability to form biofilm and to colonize fruit wounds were hypothesized as the main action mechanisms for M. pulcherrima. The production of hydrolytic enzymes and the ability to colonize the wounds were the most important mechanisms for biocontrol activity in A. pullulans and W. anomalus, which also showed high ability to form biofilm. The production of volatile organic compounds (VOCs) with in vitro and in vivo inhibitory effect on pathogen growth was observed for the species W. anomalus, S. cerevisiae and M. pulcherrima. Our study clearly indicates that multiple modes of action may explain as M. pulcherrima provide excellent control of postharvest botrytis bunch rot of grape. Copyright © 2014 Elsevier Ltd. All rights reserved.

Self-Assembled Nanoparticles of Glycyrrhetic Acid-Modified Pullulan as a Novel Carrier of Curcumin

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Roufen Yuan

2014-08-01

Full Text Available Glycyrrhetic acid (GA-modified pullulan nanoparticles (GAP NPs were synthesized as a novel carrier of curcumin (CUR with a degree of substitution (DS of GA moieties within the range of 1.2–6.2 groups per hundred glucose units. In the present study, we investigated the physicochemical characteristics, release behavior, in vitro cytotoxicity and cellular uptake of the particles. Self-assembled GAP NPs with spherical shapes could readily improve the water solubility and stability of CUR. The CUR release was sustained and pH-dependent. The cellular uptake of CUR-GAP NPs was confirmed by green fluorescence in the cells. An MTT study showed CUR-GAP NPs with higher cytotoxicity in HepG2 cells than free CUR, but GAP NPs had no significant cytotoxicity. GAP is thus an excellent carrier for the solubilization, stabilization, and controlled delivery of CUR.

Diversidad de levaduras asociadas a chichas tradicionales de Colombia

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William Andrés López-Arboleda

2010-07-01

, Saccharomyces martiniae, Dekkera anomala, Aureobasidium pullulans y Candida pseudointermedia. La caracterización preliminar de los aislados obtenidos, basada en pruebas de tolerancia a etanol y halo-tolerancia, permitió identificar levaduras nativas con posible utilización biotecnológica en el sector industrial. Palabras clave: Levaduras; diversidad; chicha; identificación molecular; biotecnología Abstract In Colombia, knowledge about yeast communities has been limited because most reports have focused on yeast species with clinical relevance. The spontaneous fermentation of different substrates creates important habitats for analyzing wild yeast populations; for this reason, in this study we isolated and identified yeasts associated with the “chichas” of corn, pineapple, and “arracacha,” which are traditional fermented Colombian beverages. The most representative yeasts were isolated from “chicha” during its three phases of fermentation: initial, tumultuous and final. Initially, we made a partial characterization of isolated yeasts, including macroscopic and microscopic descriptions, physiological tests, and measurement of capacity for producing spores and filaments. However, because these techniques were not sufficient for identification of isolated yeasts to the level of genus and species, the study was complemented by using molecular techniques based on restriction analysis of the ITS1-5.8S rRNA gene-ITS2. When this technique did not permit us to obtain positive results and confirm the PCR-RFLP results, we used the sequence of the D1/D2 domain of the 26S rRNA gene instead for most representative isolates. With these techniques, we identified the most representative yeast species of the three classes of “chicha”: Candida tropicalis, Pichia kluyveri, Pichia guilliermondii, Hanseniapora guilliermondii, Pichia fermentans, Saccharomyces cerevisiae, Candida maltosa, Rhodotorula glutinis, Torulaspora delbrueckii, Hanseniaspora uvarum, Kazachstania exigua

Diversidad de levaduras asociadas a chichas tradicionales de Colombia

Directory of Open Access Journals (Sweden)

William Andrés López-Arboleda

2011-01-01

, Saccharomyces martiniae, Dekkera anomala, Aureobasidium pullulans y Candida pseudointermedia. La caracterización preliminar de los aislados obtenidos, basada en pruebas de tolerancia a etanol y halo-tolerancia, permitió identificar levaduras nativas con posible utilización biotecnológica en el sector industrial. Palabras clave: Levaduras; diversidad; chicha; identificación molecular; biotecnología Abstract In Colombia, knowledge about yeast communities has been limited because most reports have focused on yeast species with clinical relevance. The spontaneous fermentation of different substrates creates important habitats for analyzing wild yeast populations; for this reason, in this study we isolated and identified yeasts associated with the “chichas” of corn, pineapple, and “arracacha,” which are traditional fermented Colombian beverages. The most representative yeasts were isolated from “chicha” during its three phases of fermentation: initial, tumultuous and final. Initially, we made a partial characterization of isolated yeasts, including macroscopic and microscopic descriptions, physiological tests, and measurement of capacity for producing spores and filaments. However, because these techniques were not sufficient for identification of isolated yeasts to the level of genus and species, the study was complemented by using molecular techniques based on restriction analysis of the ITS1-5.8S rRNA gene-ITS2. When this technique did not permit us to obtain positive results and confirm the PCR-RFLP results, we used the sequence of the D1/D2 domain of the 26S rRNA gene instead for most representative isolates. With these techniques, we identified the most representative yeast species of the three classes of “chicha”: Candida tropicalis, Pichia kluyveri, Pichia guilliermondii, Hanseniapora guilliermondii, Pichia fermentans, Saccharomyces cerevisiae, Candida maltosa, Rhodotorula glutinis, Torulaspora delbrueckii, Hanseniaspora uvarum, Kazachstania exigua

Diversity and antifungal activity of the endophytic fungi associated with the native medicinal cactus Opuntia humifusa (Cactaceae) from the United States.

Science.gov (United States)

Silva-Hughes, Alice F; Wedge, David E; Cantrell, Charles L; Carvalho, Camila R; Pan, Zhiqiang; Moraes, Rita M; Madoxx, Victor L; Rosa, Luiz H

2015-06-01

The endophytic fungal community associated with the native cactus Opuntia humifusa in the United States was investigated and its potential for providing antifungal compounds. A hundred-eight endophytic fungal isolates were obtained and identified by molecular methods into 17 different taxa of the genera Alternaria, Aureobasidium, Biscogniauxia, Cladosporium, Cryptococcus, Curvularia, Diaporthe, Epicoccum, Paraconiothyrium, Pestalotiopsis and Phoma. The most frequent species associated with O. humifusa were Alternaria sp. 3, Aureobasidium pullulans and Diaporthe sp. The fungal community of O. humifusa had a high richness and diversity; additionally, the species richness obtained indicates that the sample effort was enough to recover the diversity pattern obtained. Six extracts of endophytes showed antifungal properties and (1)H NMR analyses of the extracts of Alternaria sp. 5 Ohu 8B2, Alternaria sp. 3 Ohu 30A, Cladosporium funiculosum Ohu 17C1 and Paraconiothyrium sp. Ohu 17A indicated the presence of functional groups associated with unsaturated fatty-acid olefinic protons and fatty acid methylene and methyl protons. GC-FID analysis of these extracts confirmed the presence of a mixture of different fatty acids. The (1)H NMR analyses of Biscogniauxia mediterranea Ohu 19B extracts showed the presence of aromatic compounds. From the extract of B. mediterranea we isolated the compound 5-methylmellein that displayed moderate antifungal activity against the phytopathogenic fungi Phomopsis obscurans. Our results suggest that native medicinal cacti of the United States can live symbiotically with rich and diverse endophytic communities and may be a source of bioactive molecules, including those able to inhibit or control plant disease pathogens. Copyright © 2015 Elsevier GmbH. All rights reserved.

The presence of the head coach during a small-sided game: effects on players´ internal load and technical performance. [La presencia del entrenador durante un juego reducido: efectos sobre la carga interna y rendimiento técnico].

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Moisés Falces-Prieto

2015-07-01

Full Text Available The aim of the study was to examine whether the presence/absence of the head coach influenced soccer players´ heart rate (HR, rating of perceived exertion (RPE and technical performance during a small-sided game (SSG. The participants in the study were 27 young male soccer players (age: 17.0 ± 1.0 years; height: 176.0 ± 5.2 cm; weight: 67.6 ± 7.9 kg; HRmax: 195.1 ± 0.7 bpm. The SSG were practiced with the presence (PHC or absence (AHC of the head coach. Each SSG had duration of 6 min followed by a 5 min rest period. Significant differences were observed for HRmax (PHC: 190.4 ± 10.8; AHC: 182.0 ± 11.9, HRmean (PHC: 175.3 ± 9.4; AHC: 167.0 ± 13.1, RPE (PHC: 7.6 ± 0.8; AHC: 5.8 ± 1.1 and >90% HRmax (PHC: 54.09 ± 33.14; AHC: 46.71 ± 35.61. Significant differences in 4 technical actions: % success in passing (PHC: 59.05 ± 23.11; AHC: 71.08 ± 18.69, % Unsuccessful Passes (UP (PHC: 40.95 ± 23.11; AHC: 28.92 ± 18.69, Number of UP (PHC: 3.19 ± 1.69; AHC: 2.26 ± 1.58 and total number of control-conduction-passes (CCP + Successful Passes (SP (PHC: 0.81 ± 0.83, AHC: 0.52 ± 0.64. This study shows that the presence or not of the head coach during SSG significantly influences the intensity of the players and the technical/tactical actions. Resumen El objetivo del estudio fue examinar como la presencia/ausencia del entrenador, influyó sobre la frecuencia cardíaca (FC, percepción subjetiva del esfuerzo (PSE y rendimiento técnico durante un juego reducido (JR. Participaron 27 jugadores jóvenes (edad: 17.0 ± 1.0 años; altura: 176.0 ± 5.2 cm; peso: 67.6 ± 7.9 kg; FCmax: 195.1 ± 0.7 ppm. El JR fue realizado en presencia (PE /ausencia (AE del entrenador. Cada JR tuvo una duración de 6 min seguida de 5 min de recuperación. Se observaron diferencias significativas en la carga interna: PE (FCmax:190.4 ± 10.8; FCmed:175.3 ± 9.4; PSE: 7.6 ± 0.8 y >90% FCmax: 54.09 ± 33.14 AE (FCmax:182.0 ± 11.9; FCmed:167.0 ± 13.1; PSE: 5.8 ± 1.1 y

Дрожжи в борьбе с возбудителем заболевания серая гниль Botrytis cinerea

OpenAIRE

Храбрых, О.; Барайщук, Г.; Kollar, Andreas; Jelkmann, Wilhelm

2007-01-01

Серая гниль наиболее распространенное и вредоносное заболевание, вызываемое грибом Botrytis cinerea.The ability of yeasts to inhibit the growth and development of the fungus Botrytis cinerea causes grey mould was detected in vitro during co-culturing the micro organisms on agar plates and in liquid conditions. The radial growth of the pathogen was inhibited in the presence of many tested yeasts on agar plates. In liquid, Aureobasidium pullulans, Cryptococcus laurentii, Candida sake, Hansenias...

Self-assembled nanocomplexes of anionic pullulan and polyallylamine for DNA and pH-sensitive intracellular drug delivery

Science.gov (United States)

Vora, Lalit; Tyagi, Monica; Patel, Ketan; Gupta, Sanjay; Vavia, Pradeep

2014-12-01

The amalgamation of chemotherapy and gene therapy is promising treatment option for cancer. In this study, novel biocompatible self-assembled nanocomplexes (NCs) between carboxylmethylated pullulan t335 (CMP) with polyallylamine (CMP-PAA NCs) were developed for plasmid DNA (pDNA) and pH-sensitive doxorubicin (DOX) delivery. DOX was conjugated to CMP (DOX-CMP) via hydrazone and confirmed by FTIR and 1H-NMR. In vitro release studies of pH-sensitive DOX-CMP conjugate showed 23 and 85 % release after 48 h at pH 7.4 (physiological pH) and pH 5 (intracellular/tumoral pH), respectively. The CMP-PAA NCs or DOX-CMP-PAA NCs self-assembled into a nanosized (successful cellular uptake of DOX-CMP-PAA NCs in HEK293 cells. Thus, NCs hold great potential for targeted pDNA and pH-sensitive intratumoral drug delivery.

Pullulan microcarriers for bone tissue regeneration

Energy Technology Data Exchange (ETDEWEB)

Aydogdu, Hazal [Middle East Technical University, Department of Biomedical Engineering, Ankara 06800 (Turkey); Keskin, Dilek [Middle East Technical University, Department of Biomedical Engineering, Ankara 06800 (Turkey); Middle East Technical University, Department of Engineering Sciences, Ankara 06800 (Turkey); METU BIOMATEN Center of Excellence in Biomaterials and Tissue Engineering, Ankara 06800 (Turkey); Baran, Erkan Turker, E-mail: erkanturkerbaran@gmail.com [METU BIOMATEN Center of Excellence in Biomaterials and Tissue Engineering, Ankara 06800 (Turkey); Tezcaner, Aysen, E-mail: tezcaner@metu.edu.tr [Middle East Technical University, Department of Biomedical Engineering, Ankara 06800 (Turkey); Middle East Technical University, Department of Engineering Sciences, Ankara 06800 (Turkey); METU BIOMATEN Center of Excellence in Biomaterials and Tissue Engineering, Ankara 06800 (Turkey)

2016-06-01

Microcarrier systems offer a convenient way to repair bone defects as injectable cell carriers that can be applied with small incisions owing to their small size and spherical shape. In this study, pullulan (PULL) microspheres were fabricated and characterized as cell carriers for bone tissue engineering applications. PULL was cross-linked by trisodium trimetaphosphate (STMP) to enhance the stability of the microspheres. Improved cytocompatibility was achieved by silk fibroin (SF) coating and biomimetic mineralization on the surface by incubating in simulated body fluid (SBF). X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescent microscopy analysis confirmed biomimetic mineralization and SF coating on microspheres. The degradation analysis revealed that PULL microspheres had a slow degradation rate with 8% degradation in two weeks period indicating that the microspheres would support the formation of new bone tissue. Furthermore, the mechanical tests showed that the microspheres had a high mechanical stability that was significantly enhanced with the biomimetic mineralization. In vitro cell culture studies with SaOs-2 cells showed that cell viability was higher on SF and SBF coated microspheres on 7th day compared to PULL ones under dynamic conditions. Alkaline phosphatase activity was higher for SF coated microspheres in comparison to uncoated microspheres when dynamic culture condition was applied. The results suggest that both organic and inorganic surface modifications can be applied on PULL microspheres to prepare a biocompatible microcarrier system with suitable properties for bone tissue engineering. - Highlights: • Porous PULL microspheres were prepared as cell carrier for the first time. • Mineralization on the microspheres improved their mechanical properties. • Mineralization and SF coating enhanced cell proliferation on PULL microspheres.

Pullulan microcarriers for bone tissue regeneration

International Nuclear Information System (INIS)

Aydogdu, Hazal; Keskin, Dilek; Baran, Erkan Turker; Tezcaner, Aysen

2016-01-01

Microcarrier systems offer a convenient way to repair bone defects as injectable cell carriers that can be applied with small incisions owing to their small size and spherical shape. In this study, pullulan (PULL) microspheres were fabricated and characterized as cell carriers for bone tissue engineering applications. PULL was cross-linked by trisodium trimetaphosphate (STMP) to enhance the stability of the microspheres. Improved cytocompatibility was achieved by silk fibroin (SF) coating and biomimetic mineralization on the surface by incubating in simulated body fluid (SBF). X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescent microscopy analysis confirmed biomimetic mineralization and SF coating on microspheres. The degradation analysis revealed that PULL microspheres had a slow degradation rate with 8% degradation in two weeks period indicating that the microspheres would support the formation of new bone tissue. Furthermore, the mechanical tests showed that the microspheres had a high mechanical stability that was significantly enhanced with the biomimetic mineralization. In vitro cell culture studies with SaOs-2 cells showed that cell viability was higher on SF and SBF coated microspheres on 7th day compared to PULL ones under dynamic conditions. Alkaline phosphatase activity was higher for SF coated microspheres in comparison to uncoated microspheres when dynamic culture condition was applied. The results suggest that both organic and inorganic surface modifications can be applied on PULL microspheres to prepare a biocompatible microcarrier system with suitable properties for bone tissue engineering. - Highlights: • Porous PULL microspheres were prepared as cell carrier for the first time. • Mineralization on the microspheres improved their mechanical properties. • Mineralization and SF coating enhanced cell proliferation on PULL microspheres.

Blending of soluble corn fiber with pullulan, sorbitol, or fructose attenuates glycemic and insulinemic responses in the dog and affects hydrolytic digestion in vitro.

Science.gov (United States)

de Godoy, M R C; Knapp, B K; Bauer, L L; Swanson, K S; Fahey, G C

2013-08-01

The objective of these experiments was to measure in vitro hydrolytic digestion and glycemic and insulinemic responses of select carbohydrate blends, all containing the novel carbohydrate soluble corn fiber (SCF). Two SCF that varied in their method of production were used to formulate the carbohydrate blends. One set of blends contained a SCF that was spray dried (SCFsd) and then blended with different amounts of either pullulan, sorbitol, or fructose. The other set of blends contained a SCF produced using longer evaporation time (SCF) and then blended with different ratios of pullulan, sorbitol, and fructose. Free sugar concentrations found in the individual SCFsd and SCF substrates were low but varied. Spray-dried soluble corn fiber had a reduced free sugar concentration compared with SCF (2.8 vs. 14.2%). Glucose was the main free sugar found in both SCFsd and SCF but at different concentrations (2.7 vs. 12.7%, respectively). The majority of the SCFsd blends were completely hydrolyzed to their monosaccharide components. Glucose accounted for most of the hydrolyzed monosaccharides for SCFsd and all the SCFsd blends. Hydrolyzed monosaccharide concentrations for the SCF:pullulan:sorbitol:fructose blends followed similar trends to the SCFsd blends where greater percentages of fructose and sorbitol resulted in decreased (P sorbitol. Total released monosaccharides were high in SCFsd blends containing either 50% fructose or sorbitol, but the combination resulted in reduced concentrations of glucose released (P sorbitol:fructose blends also had intermediate to high released monosaccharides as a result of in vitro hydrolytic digestion. All SCF blends resulted in decreased glycemic and insulinemic responses compared with the maltodextrin control (P sorbitol in the blends had the greatest impact on glycemic and insulinemic responses, even at concentrations as low as 5% of the blends. Overall, SCF and their blends may prove beneficial as components of low glycemic

Fungi from interior organs of free-living small mammals in Czechoslovakia and Yugoslavia.

Science.gov (United States)

Hubálek, Z; Rosický, B; Otcenásek, M

1980-01-01

A total of 308 fungi was isolated from interior organs (lungs, spleen, liver) of 529 small mammals belonging to 21 species, 7 families and 3 orders (Insectivora, Chiroptera, Rodentia), some of these being potentially pathogenic to vertebrates (e.g. Aspergillus flavus, A. fumigatus, Geotrichum candidum, Mucor pusillus, Rhizopus arrhizus). In one vole (Microtus arvalis) captured in South Moravia, adiaspiromycosis (Emmonsia crescens) was demonstrated. Comparison of mycoflora of hair and that of interior organs of wild small mammals revealed that out of the total number of isolates the following fungi were represented in a higher proportion from visceral organs than from the hair: Aspergillus (A. amstelodami, A. flavus, A. repens), Aureobasidium (A. pullulans), Candida, Cladosporium (C. herbarum), Cryptococcus, Fusarium, Gliocladium (G. deliquescens), Helminthosporium, Kloeckera, Mucor (M. fragilis, M. hiemalis, M. pusillus), Paecilomyces marquandii, Penicillium (P. purpurogenum), Phoma, Rhizopus arrhizus, Scopulariopsis (S. candida, S. koningii) and Torulopsis.

Maintenance-energy-dependent dynamics of growth and poly(3-hydroxybutyrate [P(3HB] production by Azohydromonas lata MTCC 2311 using simple and renewable carbon substrates

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M. Zafar

2014-06-01

Full Text Available The dynamics of microbial growth and poly(3-hydroxybutyrate [P(3HB] production in growth/ non-growth phases of Azhohydromonas lata MTCC 2311 were studied using a maintenance-energy-dependent mathematical model. The values of calculated model kinetic parameters were: m s1 = 0.0005 h-1, k = 0.0965, µmax = 0.25 h-1 for glucose; m s1 = 0.003 h-1, k = 0.1229, µmax = 0.27 h-1 for fructose; and m s1 = 0.0076 h-1, k = 0.0694, µmax = 0.25 h-1 for sucrose. The experimental data of biomass growth, substrate consumption, and P(3HB production on different carbon substrates were mathematically fitted using non-linear least square optimization technique and similar trends, but different levels were observed at varying initial carbon substrate concentration. Further, on the basis of substrate assimilation potential, cane molasses was used as an inexpensive and renewable carbon source for P(3HB production. Besides, the physico-chemical, thermal, and material properties of synthesized P(3HB were determined which reveal its suitability in various applications.

Fungal melanins and their interactions with metals.

Science.gov (United States)

Fogarty, R V; Tobin, J M

1996-09-01

Fungal melanins are dark brown or black pigments located in cell walls. They also exist as extracellular polymers. Melanized fungi possess increased virulence and resistance to microbial attack as well as enhanced survival while under environmental stress. Melanins contain various functional groups which provide an array of multiple nonequivalent binding sites for metal ions. Pigmented Cladosporium cladosporoides was shown to biosorb 2.5- to four-fold more Ni, Cu, Zn, Cd, and Pb than albino Penicillium digitatum and at four- to six-fold higher rates. Metal desorption was significantly lower for extracellular melanin than from pigmented or albino biomass which indicated the strength of the melanin-metal bond. At equilibrium, tributyltin chloride (TBTC) concentrations of 2.5 mM, pigmented and albino Aureobasidium pullulans absorbed approximately 0.9 and 0.7 mumol TBTC mg -1 dry wt, respectively, whereas purified extracellular melanin exhibited uptake levels of approximately 22 mumol TBTC mg-1 dry wt at an equilibrium concentration of only 0.4 mM. Addition of melanin to the growth medium reduced the toxic effect of CuSO4 and TBTC due to melanin metal binding and sequestration.

American Peptide Symposium Proceedings (13th) Held in Edmonton, Alberta, Canada on June 20-25, 1993. Peptides: Chemistry, Structure and Biology

Science.gov (United States)

1993-06-20

protein . rceloMEIS w-mdeimidobenzol UtMA I,-Nfoer N-hydroxy- SONaY succinimide ester iniraioa units 14CM melanin concentrating luM keyhole limpet MCPSA...cyclic depsipeptide aureobasidin A (1), isolated as a major component from the culture medium of the black yeast Aureobasidium puUukans R 106, exhibits

Cross-reactivity among antigens of different air-borne fungi detected by ELISA using five monoclonal antibodies against Penicillium notatum.

Science.gov (United States)

Shen, H D; Lin, W L; Chen, R J; Han, S H

1990-10-01

Cross-reactivity among antigens of 12 genera of air-borne fungi, 13 species of Penicillium, and 5 species of Aspergillus was studied by ELISA using five monoclonal antibodies (MoAbs) against Penicillium notatum. Epitopes recognized by all the five MoAbs were susceptible to treatment of mild periodate oxidation and may therefore be associated with carbohydrates. Furthermore, our results showed that there is cross-reactivity among antigens of Penicillium, Aspergillus, and Eurotium species. By using these MoAbs, cross reactivity was not detected between antigens of Penicillium notatum and antigens of Fusarium solani, Alternaria porri, Cladosporium cladosporoides, Curvularia species, Nigrospora species, Aureobasidium pullulans, Wallemia species, Rhizopus arrhizus, and Candida albicans. Cross-reactivity among antigens of 11 species of Penicillium and 5 species of Aspergillus could be detected by ELISA using one of the five MoAbs (MoAb P15). The fact that there may be cross-reactivity among antigens of closely related fungi species should be considered in the diagnosis and treatment of mold allergic diseases.

Genetics of trehalose biosynthesis in desert-derived Aureobasidium melanogenum and role of trehalose in the adaptation of the yeast to extreme environments.

Science.gov (United States)

Jiang, Hong; Liu, Guang-Lei; Chi, Zhe; Hu, Zhong; Chi, Zhen-Ming

2018-04-01

Melanin plays an important role in the stress adaptation of Aureobasidium melanogenum XJ5-1 isolated from the Taklimakan desert. A trehalose-6-phosphate synthase gene (TPS1 gene) was cloned from K5, characterized, and then deleted to determine the role of trehalose in the stress adaptation of the albino mutant K5. No stress response element and heat shock element were found in the promoter of the TPS1 gene. Deletion of the TPS1 gene in the albino mutant rendered a strain DT43 unable to synthesize any trehalose, but DT43 still could grow in glucose, suggesting that its hexokinase was insensitive to inhibition by trehalose-6-phosphate. Overexpression of the TPS1 gene enhanced trehalose biosynthesis in strain ET6. DT43 could not grow at 33 °C, whereas K5, ET6, and XJ5-1 could grow well at this temperature. Compared with K5 and ET6, DT43 was highly sensitive to heat shock treatment, high oxidation, and high desiccation, but all the three strains demonstrated the same sensitivity to UV light and high NaCl concentration. Therefore, trehalose played an important role in the adaptation of K5 to heat shock treatment, high oxidation, and high desiccation.

Enhanced conjugation stability and blood circulation time of macromolecular gadolinium-DTPA contrast agent

Energy Technology Data Exchange (ETDEWEB)

Jenjob, Ratchapol [Department of New Drug Development, School of Medicine, Inha University, 2F A-dong, Jeongseok Bldg., Sinheung-dong 3-ga, Jung-gu, Incheon 400-712 (Korea, Republic of); Kun, Na [Department of Biotechnology, The Catholic University of Korea, 43 Jibong-ro, Wonmi-gu, Bucheon-si, Gyeonggi-do 420-743 (Korea, Republic of); Ghee, Jung Yeon [Utah-Inha DDS and Advanced Therapeutics, B-403 Meet-You-All Tower, SongdoTechnopark, 7–50, Songdo-dong, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Shen, Zheyu; Wu, Xiaoxia [Division of Functional Materials and Nano-Devices, Ningbo Institute of Materials Technology & Engineering (NIMTE), Chinese Academy of Sciences, 519 Zhuangshi Street, Zhenhai District, Ningbo, Zhejiang 315201 (China); Cho, Steve K., E-mail: scho@gist.ac.kr [Division of Liberal Arts and Science, GIST College, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of); Lee, Don Haeng [Utah-Inha DDS and Advanced Therapeutics, B-403 Meet-You-All Tower, SongdoTechnopark, 7–50, Songdo-dong, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Department of Internal Medicine, School of Medicine, Inha University Hospital, Incheon 420-751 (Korea, Republic of); Yang, Su-Geun, E-mail: Sugeun.Yang@Inha.ac.kr [Department of New Drug Development, School of Medicine, Inha University, 2F A-dong, Jeongseok Bldg., Sinheung-dong 3-ga, Jung-gu, Incheon 400-712 (Korea, Republic of)

2016-04-01

In this study, we prepared macromolecular MR T1 contrast agent: pullulan-conjugated Gd diethylene triamine pentaacetate (Gd-DTPA-Pullulan) and estimated residual free Gd{sup 3+}, chelation stability in competition with metal ions, plasma and tissue pharmacokinetics, and abdominal MR contrast on rats. Residual free Gd{sup 3+} in Gd-DTPA-Pullulan was measured using colorimetric spectroscopy. The transmetalation of Gd{sup 3+} incubated with Ca{sup 2+} was performed by using a dialysis membrane (MWCO 100–500 Da) and investigated by ICP-OES. The plasma concentration profiles of Gd-DTPA-Pullulan were estimated after intravenous injection at a dose 0.1 mmol/kg of Gd. The coronal-plane abdominal images of normal rats were observed by MR imaging. The content of free Gd{sup 3+}, the toxic residual form, was less than 0.01%. Chelation stability of Gd-DTPA-Pullulan was estimated, and only 0.2% and 0.00045% of Gd{sup 3+} were released from Gd-DTPA-Pullulan after 2 h incubation with Ca{sup 2+} and Fe{sup 2+}, respectively. Gd-DTPA-Pullulan displayed the extended plasma half-life (t{sub 1/2,α} = 0.43 h, t{sub 1/2,β} = 2.32 h), much longer than 0.11 h and 0.79 h of Gd-EOB-DTPA. Abdominal MR imaging showed Gd-DTPA-Pullulan maintained initial MR contrast for 30 min. The extended plasma half-life of Gd-DTPA-Pullulan probably allows the prolonged MR acquisition time in clinic with enhanced MR contrast. - Highlights: • Macromolecule (pullulan) conjugated Gd contrast agent (Gd-DTPA-Pullulan) showed the extended plasma half-life (t{sub 1/2,α} = 0.43 h, t{sub 1/2,β} = 2.32 h) in comparison with Gd-EOB-DTPA • Gd-DTPA-pullulan T1 contrast agent exhibited strong chelation stability against Gd. • The extended blood circulation attributed the enhanced and prolonged MR contrast on abdominal region of rats. • The extended blood circulation may provide prolonged MR acquisition time window in clinics.

Development of ecofriendly bionanocomposite: Whey protein isolate/pullulan films with nano-SiO2.

Science.gov (United States)

Hassannia-Kolaee, Mahbobeh; Khodaiyan, Faramarz; Pourahmad, Rezvan; Shahabi-Ghahfarrokhi, Iman

2016-05-01

During the past decade, the limitation of petroleum based polymers, the high price of oil, and the environmental concern were attracted the attention of researchers to develop biobased polymers. The composition of different biopolymers and the reinforcement with nano filler are common methods to improve the drawbacks of biopolymers. In this study whey protein isolate/pullulan (WPI/PUL) films contain 1%, 3%, and 5% (w/w) nano-SiO2 (NS) were prepared by a casting method. Tensile strength of nanocomposite films increased after increasing NS content, but elongation at break decreased, simultaneously. Water absorption, moisture content, solubility in water improved in the wake of increasing NS content because NS increase the cohesiveness of the polymer matrix and improved the barrier and water resistance properties of the films. water vapor permeability of film specimens decreased by increasing NS content. Uniform distribution of NS into polymer matrix was confirmed by scanning electron microscopy (SEM). XRD pattern and thermal analysis revealed increasing crystallinity and increasing Tg of film specimens with increasing NS content, respectively. According to our result WPI/PUL/NS films possess potential to be used as environment friendly packaging films to improve shelf life of food and can be used as promising alternative to petroleum based packaging films. Copyright © 2016 Elsevier B.V. All rights reserved.

Self-assembled nanocomplexes of anionic pullulan and polyallylamine for DNA and pH-sensitive intracellular drug delivery

International Nuclear Information System (INIS)

Vora, Lalit; Tyagi, Monica; Patel, Ketan; Gupta, Sanjay; Vavia, Pradeep

2014-01-01

The amalgamation of chemotherapy and gene therapy is promising treatment option for cancer. In this study, novel biocompatible self-assembled nanocomplexes (NCs) between carboxylmethylated pullulan t335 (CMP) with polyallylamine (CMP–PAA NCs) were developed for plasmid DNA (pDNA) and pH-sensitive doxorubicin (DOX) delivery. DOX was conjugated to CMP (DOX–CMP) via hydrazone and confirmed by FTIR and 1 H-NMR. In vitro release studies of pH-sensitive DOX–CMP conjugate showed 23 and 85 % release after 48 h at pH 7.4 (physiological pH) and pH 5 (intracellular/tumoral pH), respectively. The CMP–PAA NCs or DOX–CMP–PAA NCs self-assembled into a nanosized (<250 nm) spherical shape as confirmed by DLS and TEM. The hemolysis and cytotoxicity study indicated that the CMP–PAA NCs did not show cytotoxicity in comparison with plain polyallylamine. Gel retardation assay showed complete binding of pDNA with CMP–PAA NCs at 1:2 weight ratio. CMP–PAA NCs/pDNA showed significantly higher transfection in HEK293 cells compared to PAA/pDNA complexes. Confocal imaging demonstrated successful cellular uptake of DOX–CMP–PAA NCs in HEK293 cells. Thus, NCs hold great potential for targeted pDNA and pH-sensitive intratumoral drug delivery

On Positive Solutions for the Rational Difference Equation Systems x n+1 = A/x n y n (2), and y n+1 = By n /x n-1 y n-1.

Science.gov (United States)

Ma, Hui-Li; Feng, Hui

2014-01-01

Our aim in this paper is to investigate the behavior of positive solutions for the following systems of rational difference equations: x n+1 = A/x n y n (2), and y n+1 = By n /x n-1 y n-1, n = 0,1,…, where x -1, x 0, y -1, and y 0 are positive real numbers and A and B are positive constants.

76 FR 16686 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Science.gov (United States)

2011-03-25

... Butler Butler County/K W 1/4580 2/3/11 ILS or LOC RWY 8, Amdt 7B Scholter Field. 7-Apr-11 FL Orlando Orlando Sanford 1/4606 2/3/11 ILS or LOC RWY 9L, Amdt 3 Intl. 7-Apr-11 FL Orlando Orlando Sanford 1/4608 2/3/11 NDB B, Orig Intl. 7-Apr-11 FL Orlando Orlando Sanford 1/4609 2/3/11 ILS or LOC RWY 27R, Amdt 1...

QUANTITATIVE FLUORESCENCE IN SITU HYBRIDIZATION OF AUREOBASIDIUM PULLULANS ON MICROSCOPE SLIDES AND LEAF SURFACES. (R823845)

Science.gov (United States)

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Increased prevalence of IgG-induced sensitization and hypersensitivity pneumonitis (humidifier lung) in nonsmokers exposed to aerosols of a contaminated air conditioner.

Science.gov (United States)

Baur, X; Richter, G; Pethran, A; Czuppon, A B; Schwaiblmair, M

1992-01-01

Specific IgG antibodies against antigens of a contaminated air conditioner were estimated in serum of 134 workers of a printing company. Altogether 64% of the workers investigated revealed significantly elevated levels (> 3 U/ml) of IgG antibodies specific to these antigens as compared to a nonexposed control group. The occurrence of IgG antibodies for microbial extracts were 25% for Fusarium, 23% for Penicillium notatum, 13% for Alternaria tenuis, 12% for Aureobasidium pullulans, 9% for Sphaeropsidales species, 3% for Micropolyspora faeni, 2% for Aspergillus fumigatus and 2% for Thermoactionomyces vulgaris. Out of the 86 workers with elevated IgG antibodies for air conditioner antigens, 59 were nonsmokers. Considering a cut-off level of 10 U/ml IgG for high values, the proportion of smokers to nonsmokers becomes even more pronounced (6 to 36 respectively, binominal test p air conditioners are the best choice as antigen source for the diagnosis of humidifier lung in exposed workers. Nonsmokers are shown to have a high risk for immunological sensitization.

Fungi associated with black mould on baobab trees in southern Africa.

Science.gov (United States)

Cruywagen, Elsie M; Crous, Pedro W; Roux, Jolanda; Slippers, Bernard; Wingfield, Michael J

2015-07-01

There have been numerous reports in the scientific and popular literature suggesting that African baobab (Adansonia digitata) trees are dying, with symptoms including a black mould on their bark. The aim of this study was to determine the identity of the fungi causing this black mould and to consider whether they might be affecting the health of trees. The fungi were identified by sequencing directly from mycelium on the infected tissue as well as from cultures on agar. Sequence data for the ITS region of the rDNA resulted in the identification of four fungi including Aureobasidium pullulans, Toxicocladosporium irritans and a new species of Rachicladosporium described here as Rachicladosporium africanum. A single isolate of an unknown Cladosporium sp. was also found. These fungi, referred to here as black mould, are not true sooty mould fungi and they were shown to penetrate below the bark of infected tissue, causing a distinct host reaction. Although infections can lead to dieback of small twigs on severely infected branches, the mould was not found to kill trees.

Plant-microbe interactions: Plant hormone production by phylloplane fungi. Research report

Energy Technology Data Exchange (ETDEWEB)

Tuomi, T.; Ilvesoksa, J.; Rosenqvist, H.

1993-06-23

The molds Botrytis cinerea, Cladosporium cladosporioides and the yeast Aureobasidium pullulans, isolated from the leaves of three short-rotation Salix clones, were found to produce indole-3-acetic acid (a growth promoter of plants). Abscisic acid (a growth inhibitor of plants) production was detected in B. cinerea. The contents of indole-3-acetic acid and abscisic acid in the leaves of the Salix clones and the amounts of fungal propagules in these leaves were also measured, in order to evaluate whether the amounts of plant growth regulators produced by the fungi would make a significant contribution to the hormonal quantities of the leaves. The content of abscisic acid, and to a lesser degree that of indole-3-acetic acid, showed a positive correlation with the frequency of infection by the hormone producing organisms. The amounts of hormone producing fungi on leaves that bore visible colonies were, however, not sufficiently high to support the argument that neither the fungal production of abscisic nor indole-3-acetic acid would to a significant degree contribute to the hormonal contents of the leaves of the Salix clones.

New view on In{sub x}Ga{sub 1-x}N{sub y}As{sub 1-y}alloys

Energy Technology Data Exchange (ETDEWEB)

Elyukhin, Vyacheslav A. [Departamento de Ingenieria Electrica, Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Avenida Instituto Politecnico Nacional 2508, 07360, Mexico (Mexico)

2015-12-15

Semiconductors with isoelectronic centers are actively studied to fabricate arrays of identical single photon emitters. Self-assembling of 4N10In and 1N4In clusters in GaAs-rich In{sub x}Ga{sub 1-x}N{sub y}As{sub 1-y} is represented. All or almost all In atoms are in 4N10In clusters from 0 to 800 C in In{sub x}Ga{sub 1-x}N{sub y}As{sub 1-y} with x = 1 x 10{sup -4}, y = 1 x 10{sup -4} and x = 1 x 10{sup -5}, y = 1 x 10{sup -5}. All or almost all nitrogen atoms are in 1N4In clusters if x = 0.01, y = 1 x 10{sup -4} and x = 1 x 10{sup -3}, y = 1 x 10{sup -6}. There are both types of clusters in alloys with x = 5 x 10{sup -5}, y = 5 x 10{sup -7}; x = 2 x 10{sup -4}, y = 2 x 10{sup -6}; x = 1 x 10{sup -4}, y = 1 x 10{sup -5} and x = 2 x 10{sup -3}, y = 2 x 10{sup -4} and portions of nitrogen atoms in clusters depend on the composition and temperature. Thus, In{sub x}Ga{sub 1-x}N{sub y}As{sub 1-y} are promising semiconductors to obtain arrays of identical isoelectronic clusters with the desirable density. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Enhanced conjugation stability and blood circulation time of macromolecular gadolinium-DTPA contrast agent.

Science.gov (United States)

Jenjob, Ratchapol; Kun, Na; Ghee, Jung Yeon; Shen, Zheyu; Wu, Xiaoxia; Cho, Steve K; Lee, Don Haeng; Yang, Su-Geun

2016-04-01

In this study, we prepared macromolecular MR T1 contrast agent: pullulan-conjugated Gd diethylene triamine pentaacetate (Gd-DTPA-Pullulan) and estimated residual free Gd(3+), chelation stability in competition with metal ions, plasma and tissue pharmacokinetics, and abdominal MR contrast on rats. Residual free Gd(3+) in Gd-DTPA-Pullulan was measured using colorimetric spectroscopy. The transmetalation of Gd(3+) incubated with Ca(2+) was performed by using a dialysis membrane (MWCO 100-500 Da) and investigated by ICP-OES. The plasma concentration profiles of Gd-DTPA-Pullulan were estimated after intravenous injection at a dose 0.1 mmol/kg of Gd. The coronal-plane abdominal images of normal rats were observed by MR imaging. The content of free Gd(3+), the toxic residual form, was less than 0.01%. Chelation stability of Gd-DTPA-Pullulan was estimated, and only 0.2% and 0.00045% of Gd(3+) were released from Gd-DTPA-Pullulan after 2h incubation with Ca(2+) and Fe(2+), respectively. Gd-DTPA-Pullulan displayed the extended plasma half-life (t1/2,α=0.43 h, t1/2,β=2.32 h), much longer than 0.11h and 0.79 h of Gd-EOB-DTPA. Abdominal MR imaging showed Gd-DTPA-Pullulan maintained initial MR contrast for 30 min. The extended plasma half-life of Gd-DTPA-Pullulan probably allows the prolonged MR acquisition time in clinic with enhanced MR contrast. Copyright © 2016 Elsevier B.V. All rights reserved.

Site Environmental Report for 2008, Volume 1

Energy Technology Data Exchange (ETDEWEB)

Lackner, Regina; Baskin, David; Fox, Robert; Jelinski, John; Pauer, Ron; Thorson, Patrick; Wahl, Linnea; Xu, Suying

2009-09-21

The Site Environmental Report for 2008 is an integrated report on the environmental programs at Lawrence Berkeley National Laboratory and satisfies the requirements of DOE order 231.1A, Environment, Safety, and Health Reporting. Volume II contains individual data results from surveillance and monitoring activities

Application of ATR-FTIR Spectroscopy to Compare the Cell Materials of Wood Decay Fungi with Wood Mould Fungi

Directory of Open Access Journals (Sweden)

Barun Shankar Gupta

2015-01-01

Full Text Available Wood fungi create vast damage among standing trees and all types of wood materials. The objectives of this study are to (a characterize the cell materials of two major wood decay fungi (Basidiomycota, namely, Trametes versicolor and Postia placenta, and (b compare the cell materials of decay fungi with four wood mould fungi (Ascomycota, namely, Aureobasidium pullulans, Alternaria alternata, Cladosporium cladosporioides, and Ulocladium atrum. Fourier transform infrared (FTIR spectroscopy is used to characterize the microbial cellular materials. The results showed that the IR bands for the fatty acid at ∼2900 cm−1 were different for the two-decay-fungi genre. Postia placenta shows more absorbance peaks at the fatty acid region. Band ratio indices for amide I and amide II from protein amino acids were higher for the mould fungi (Ascomycota than the decay fungi (Basidiomycota. Similarly, the band ratio index calculated for the protein end methyl group was found to be higher for the mould fungi than the decay fungi. Mould fungi along with the decay fungi demonstrated a positive correlation (R2=0.75 between amide I and amide II indices. The three-component multivariate, principal component analysis showed a strong correlation of amide and protein band indices.

Análise da contaminação fúngica em amostras de Cassia acutifolia Delile (sene e Peumus boldus (Molina Lyons (boldo-do-Chile comercializadas na cidade de Campinas, Brasil Analysis of the fungal contamination in Cassia acutifolia Delile (sene and Peumus boldus (Molina Lyons (boldo-do-Chile sold in Campinas, Brazil

Directory of Open Access Journals (Sweden)

Liliana de O. Rocha

2004-12-01

Full Text Available A sociedade atual tem buscado a fitoterapia como um importante recurso terapêutico, sendo a avaliação da qualidade microbiológica destes produtos um requisito essencial, considerando a sua origem. Deste modo, o objetivo da pesquisa foi realizar a contagem e a identificação de fungos filamentosos em 20 amostras de folhas de Cassia acutifolia Delile (sene e de Peumus boldus (Molina Lyons (boldo-do-Chile comercializadas em farmácias de manipulação e mercados da cidade de Campinas, Brasil, usando as técnicas microbiológicas clássicas. Os resultados obtidos evidenciaram que 45% das amostras analisadas se situavam fora dos padrões estabelecidos pela Organização Mundial da Saúde (OMS. Não foram observadas diferenças significativas na análise quantitativa da contaminação fúngica entre amostras comercializadas em farmácias de manipulação e mercados, tanto para o boldo-do-Chile como para a sene. Os fungos identificados nestas amostras foram: Aspergillus, Penicillium, Phoma, Cladosporium, Trichoderma, Rhizopus, Mucor, Aureobasidium pullulans, Mycelia sterilia, Acremonium e Monilia sitophila. Estes resultados demonstraram o baixo nível de qualidade desses fitoterápicos, pois, além do elevado número de amostras contaminadas, foram identificados fungos de gêneros produtores de micotoxinas, como o Aspergillus e o Penicillium. Verifica-se a urgência na realização de adequado controle de qualidade microbiológico dos fitoterápicos e de implantação de fiscalização efetiva, para garantir a segurança e eficácia destes produtos.The consumption of medicinal plants has increased during the last years. The purpose of this study was to evaluate and identify fungi specimens present in samples of Cassia acutifolia Delile (20 (sene and Peumus boldus (Molina Lyons (Boldo-do-Chile (20, that were purchased in drugstores and markets of Campinas, Brazil, by usual methods. The results showed that 45% of samples did not fit the minimum

Differential roles for neuropeptide Y Y1 and Y5 receptors in anxiety and sedation

DEFF Research Database (Denmark)

Sørensen, Gunnar; Lindberg, Camilla; Wörtwein, Gitta

2004-01-01

PP(1-7),NPY(19-23),Ala(31),Aib(32),Gln(34)]hPP) in the elevated plus maze and open field tests. As with NPY, the Y1 agonist had a dose-dependent anxiolytic-like effect in both behavioral tests. In contrast to NPY, which caused significant sedation in the open field test, the Y1 agonist was without...... sedative effect. The Y2 agonist showed neither anxiolytic-like nor sedative effects. The Y5 agonist showed anxiolytic-like activity in both behavioral tests and caused sedation in the same dose range as NPY in the open field test. These results indicate that anxiolytic-like effects of i...... NPY receptors in anxiety and sedation remains a possibility. In the present study, we addressed this issue by testing the effects of intracerebroventricular (i.c.v.) injection of NPY as well as specific receptor agonists for the Y1 receptor ([D-His(26)]NPY), Y2 receptor (C2-NPY), and Y5 receptor ([c...

Crosslinked pullulan/cellulose acetate fibrous scaffolds for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Atila, Deniz [Department of Engineering Sciences, Middle East Technical University (Turkey); Keskin, Dilek [Department of Engineering Sciences, Middle East Technical University (Turkey); Biomaterials and Tissue Engineering Center of Excellence, Middle East Technical University (Turkey); Tezcaner, Ayşen, E-mail: tezcaner@metu.edu.tr [Department of Engineering Sciences, Middle East Technical University (Turkey); Biomaterials and Tissue Engineering Center of Excellence, Middle East Technical University (Turkey)

2016-12-01

Natural polymer based fibrous scaffolds have been explored for bone tissue engineering applications; however, their inadequate 3-dimensionality and poor mechanical properties are among the concerns for their use as bone substitutes. In this study, pullulan (P) and cellulose acetate (CA), two polysaccharides, were electrospun at various P/CA ratios (P{sub 80}/CA{sub 20}, P{sub 50}/CA{sub 50}, and P{sub 20}/CA{sub 80}%) to develop 3D fibrous network. The scaffolds were then crosslinked with trisodium trimetaphosphate (STMP) to improve the mechanical properties and to delay fast weight loss. The lowest weight loss was observed for the groups that were crosslinked with P/STMP 2/1 for 10 min. Fiber morphologies of P{sub 50}/CA{sub 50} were more uniform without phase separation and this group was crosslinked most efficiently among groups. It was found that mechanical properties of P{sub 20}/CA{sub 80} and P{sub 50}/CA{sub 50} were higher than that of P{sub 80}/CA{sub 20.} After crosslinking strain values of P{sub 50}/CA{sub 50} scaffolds were improved and these scaffolds became more stable. Unlike P{sub 80}/CA{sub 20,} uncrosslinked P{sub 50}/CA{sub 50} and P{sub 20}/CA{sub 80} were not lost in PBS. Among all groups, crosslinked P{sub 50}/CA{sub 50} scaffolds had more uniform pores; therefore this group was used for bioactivity and cell culture studies. Apatite-like structures were observed on fibers after SBF incubation. Human Osteogenic Sarcoma Cell Line (Saos-2) seeded onto crosslinked P{sub 50}/CA{sub 50} scaffolds adhered and proliferated. The functionality of cells was tested by measuring ALP activity of the cells and the results indicated their osteoblastic differentiation. In vitro tests showed that scaffolds were cytocompatible. To sum up, crosslinked P{sub 50}/CA{sub 50} scaffolds were proposed as candidate cell carriers for bone tissue engineering applications. - Highlights: • Crosslinked 3D electrospun P/CA scaffolds were prepared for the first time. • CA

Characterization of pectinase activity for enology from yeasts occurring in Argentine Bonarda grape

Science.gov (United States)

Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata

2015-01-01

Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce β-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking. PMID:26413065

Oil type and cross-linking influence growth of Aureobasidium melanogenum on vegetable oils as a single carbon source.

Science.gov (United States)

Peeters, Loes H M; Huinink, Hendrik P; Voogt, Benjamin; Adan, Olaf C G

2018-03-12

Aureobasidium melanogenum is the main fungus found in a spontaneously formed biofilm on a oil-treated wood. This dark colored biofilm functions as a protective coating. To better understand biofilm formation, in this study A. melanogenum was cultured on olive oil and raw linseed oil. Metabolic activity and oil conversion were measured. The results show that A. melanogenum is able to grow on linseed oil and olive oil as a single carbon source. The fungus produces the enzyme lipase to convert the oil into fatty acids and glycerol. Metabolic activity and oil conversion were equal on linseed oil and olive oil. The fungus was not able to grow on severe cross-linked linseed oil, meaning that the degree of cross-linking of the oil is important for growth of A. melanogenum. Dark coloring of the colony was seen on linseed oil, which might be a stress response on the presence of autoxidation products in linseed oil. The colony on olive oil showed delayed melanin production indicating an inhibitory effect of olive oil on melanin production. © 2018 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

[Preparation and spectral characterization of CdS(y)Te(1-y) thin films].

Science.gov (United States)

Li, Wei; Feng, Liang-Huan; Wu, Li-Li; Zhang, Jing-Quan; Li, Bing; Lei, Zhi; Cai, Ya-Ping; Zheng, Jia-Gui; Cai, Wei; Zhang, Dong-Min

2008-03-01

CdS(y)Te(1-y) (0 co-evaporation of powders of CdTe and CdS. For the characterization of the structure and composition of the CdS(y)Te(1-y) thin films the X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) were used. The results indicate that the values of sulfur content y detected and controlled by the quartz wafer detector show good agreement with the EDS results. The films were found to be cubic for x or = 0.3. The 20-50 nm of grain sizes for CdS(y)Te(1-y) thin films were calculated using a method of XRD analysis. Finally, the optical properties of CdS(y)Te(1-y) thin films were characterized by UV-Vis-NIR spectroscopy alone. According to a method from Swanepoel, together with the first-order Sellmeier model, the thickness, of d-535 nm, energy gap of E(g)-1.41 eV, absorption coefficient, alpha(lambda) and refractive index, n(lambda) of CdS(0.22) Te(0.78) thin films were determined from the transmittance at normal incidence of light in the wavelength range 300-2 500 nm. The results also indicate that the CdS(y)Te(1-y) thin films with any composition (0 co-evaporation, and the method to characterize the optical properties of CdS(y)Te(1-y) thin films can be implemented for other semiconductor thin films.

Purification and properties of a thermostable pullulanase from Clostridium thermosulfurgenes EM1 which hydrolyses both. alpha. -1,6 and. alpha. -1,4-glycosidic linkages

Energy Technology Data Exchange (ETDEWEB)

Spreinat, A [Goettingen Univ. (Germany, F.R.). Inst. fuer Mikrobiologie; Antranikian, G [Technische Univ. Hamburg-Harburg, Hamburg (Germany, F. R.). Arbeitsbereich Biotechnologie 1

1990-08-01

A novel thermostable pullulanase, secreted by the thermophilic anaerobic bacterium Clostridium thermosulfurogenes EM1, was purified and characterized. Applying anion exchange chromatography and gel filtration the enzyme was purified 47-fold and had a specific activity of 200 units/mg. The molecular mass of this thermostable enzyme was determined to be 102 000 daltons and consisted of a single subunit. The enzyme was able to attack specifically the {alpha}-1,6-glycosidic linkages in pullulan and caused its complete hydrolysis to maltotriose. Surprisingly and unlike the enzyme from Klebsiella pneumoniae, the purified enzyme from this anaerobic thermophile exhibited, in addition to its debranching and pullulanase activity, an {alpha}-1,4 hydrolysing activity as well. By the action of this single polypeptide chain various branched and linear polysaccharides were completely converted to two major products, namely maltose and maltotriose. The K{sub m} values of this enzyme for pullulan and amylose were determined to be 1.33 mg/ml and 0.38 mg/ml, respectively. This debranching enzyme displays a temperature optimum at 60deg-65deg C and a pH optimum at 5.5-6.0. The application of this new class of pullulanase (pullulanase type II) in industry will significantly enhance the starch saccharification process. (orig.).

Impact of concomitant Y and Mn substitution on properties of La{sub 1-z}Y{sub z}Fe{sub 1-y}Mn{sub y}AsO{sub 0.9}F{sub 0.1}

Energy Technology Data Exchange (ETDEWEB)

Kappenberger, Rhea; Hammerath, Franziska; Wurmehl, Sabine; Buechner, Bernd [Leibniz Institute for Solid State and Materials Research Dresden, IFW Dresden (Germany); Institut fuer Festkoerperphysik, TU Dresden, Dresden (Germany); Asfaw Afrassa, Mesfin [Leibniz Institute for Solid State and Materials Research Dresden, IFW Dresden (Germany); Addis Ababa University, College of Natural Science, Addis Ababa (Ethiopia); Rousse, Pierre; Hess, Christian; Prando, Giacomo; Moroni, Matteo; Wolter, Anja U.B. [Leibniz Institute for Solid State and Materials Research Dresden, IFW Dresden (Germany); Sanna, Samuele; Carretta, Pietro [Dipartimento di Fisica e Unita di CNISM, Pavia (Italy); Lamura, Gianrico [Universita di Genova (Italy); CNR-SPIN, Genova (Italy); Kamusella, Sirko; Klauss, Hans-Henning [Institut fuer Festkoerperphysik, TU Dresden, Dresden (Germany)

2016-07-01

The substitution of constituents is frequently used as a local probe to check the microscopic properties of an unconventional superconductor in response to such an ''impurity''. In this talk, we present several structural parameters and the superconducting critical temperatures in response to different substitution levels of Mn and Y in La{sub 1-z}Y{sub z}Fe{sub 1-y}Mn{sub y}AsO{sub 0.9}F{sub 0.1}. We will discuss our findings in the light of chemical pressure inflicted by Y, which has a significantly smaller ionic radius than La, and strong electron localization caused by small amounts of paramagnetic Mn impurities.

House Fly (Musca domestica L. Attraction to Insect Honeydew.

Directory of Open Access Journals (Sweden)

Kim Y Hung

Full Text Available House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the

House Fly (Musca domestica L.) Attraction to Insect Honeydew.

Science.gov (United States)

Hung, Kim Y; Michailides, Themis J; Millar, Jocelyn G; Wayadande, Astri; Gerry, Alec C

2015-01-01

House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

House Fly (Musca domestica L.) Attraction to Insect Honeydew

Science.gov (United States)

Hung, Kim Y.; Michailides, Themis J.; Millar, Jocelyn G.; Wayadande, Astri; Gerry, Alec C.

2015-01-01

House flies are of major concern as vectors of food-borne pathogens to food crops. House flies are common pests on cattle feedlots and dairies, where they develop in and feed on animal waste. By contacting animal waste, house flies can acquire human pathogenic bacteria such as Escherichia coli and Salmonella spp., in addition to other bacteria, viruses, or parasites that may infect humans and animals. The subsequent dispersal of house flies from animal facilities to nearby agricultural fields containing food crops may lead to pre-harvest food contamination with these pathogens. We hypothesized that odors from honeydew, the sugary excreta produced by sucking insects feeding on crops, or molds and fungi growing on honeydew, may attract house flies, thereby increasing the risk of food crop contamination. House fly attraction to honeydew-contaminated plant material was evaluated using a laboratory bioassay. House flies were attracted to the following plant-pest-honeydew combinations: citrus mealybug on squash fruit, pea aphid on faba bean plants, whitefly on navel orange and grapefruit leaves, and combined citrus mealybug and cottony cushion scale on mandarin orange leaves. House flies were not attracted to field-collected samples of lerp psyllids on eucalyptus plants or aphids on crepe myrtle leaves. Fungi associated with field-collected honeydews were isolated and identified for further study as possible emitters of volatiles attractive to house flies. Two fungal species, Aureobasidium pullulans and Cladosporium cladosporioides, were repeatedly isolated from field-collected honeydew samples. Both fungal species were grown in potato dextrose enrichment broth and house fly attraction to volatiles from these fungal cultures was evaluated. House flies were attracted to odors from A. pullulans cultures but not to those of C. cladosporioides. Identification of specific honeydew odors that are attractive to house flies could be valuable for the development of improved house

Yeasts and coliform bacteria of water accumulated in bromeliads of mangrove and sand dune ecosystems of southeast Brazil.

Science.gov (United States)

Hagler, A N; Rosa, C A; Morais, P B; Mendonça-Hagler, L C; Franco, G M; Araujo, F V; Soares, C A

1993-10-01

Yeasts and coliform bacteria were isolated from water that accumulated in the central cups and adjacent leaf axilae of two bromeliads, Neoregelia cruenta of a coastal sand dune and Quesnelia quesneliana of a mangrove ecosystem near the city of Rio de Janeiro, Brazil. The mean total coliform counts were above 10,000 per 100 mL for waters of both plants, but the mean fecal coliform counts were only 74 per 100 mL for Q. quesneliana and mostly undetected in water from N. cruenta. Of 90 fecal coliform isolates, 51 were typical of Escherichia coli in colony morphology and indol, methyl red, Volges-Proskauer, and citrate (IMViC) tests. Seven representatives of the typical E. coli cultures were identified as this species, but the identifications of nine other coliform bacteria were mostly dubious. The yeast community of N. cruenta was typical of plant surfaces with basidiomycetous yeasts anamorphs, and the black yeast Aureobasidium pullulans was prevalent. Quesnelia quesneliana had a substantial proportion of ascomycetous yeasts and their anamorphs, including a probable new biotype of Saccharomyces unisporus. Our results suggested that the microbial communities in bromeliad waters are typically autochtonous and not contaminants.

Genome sequence of the olive tree, Olea europaea.

Science.gov (United States)

Cruz, Fernando; Julca, Irene; Gómez-Garrido, Jèssica; Loska, Damian; Marcet-Houben, Marina; Cano, Emilio; Galán, Beatriz; Frias, Leonor; Ribeca, Paolo; Derdak, Sophia; Gut, Marta; Sánchez-Fernández, Manuel; García, Jose Luis; Gut, Ivo G; Vargas, Pablo; Alioto, Tyler S; Gabaldón, Toni

2016-06-27

The Mediterranean olive tree (Olea europaea subsp. europaea) was one of the first trees to be domesticated and is currently of major agricultural importance in the Mediterranean region as the source of olive oil. The molecular bases underlying the phenotypic differences among domesticated cultivars, or between domesticated olive trees and their wild relatives, remain poorly understood. Both wild and cultivated olive trees have 46 chromosomes (2n). A total of 543 Gb of raw DNA sequence from whole genome shotgun sequencing, and a fosmid library containing 155,000 clones from a 1,000+ year-old olive tree (cv. Farga) were generated by Illumina sequencing using different combinations of mate-pair and pair-end libraries. Assembly gave a final genome with a scaffold N50 of 443 kb, and a total length of 1.31 Gb, which represents 95 % of the estimated genome length (1.38 Gb). In addition, the associated fungus Aureobasidium pullulans was partially sequenced. Genome annotation, assisted by RNA sequencing from leaf, root, and fruit tissues at various stages, resulted in 56,349 unique protein coding genes, suggesting recent genomic expansion. Genome completeness, as estimated using the CEGMA pipeline, reached 98.79 %. The assembled draft genome of O. europaea will provide a valuable resource for the study of the evolution and domestication processes of this important tree, and allow determination of the genetic bases of key phenotypic traits. Moreover, it will enhance breeding programs and the formation of new varieties.

Study of Stark Effect in n-doped 1.55 μm InN0.92yP1-1.92yBiy/InP MQWs

Science.gov (United States)

Bilel, C.; Chakir, K.; Rebey, A.; Alrowaili, Z. A.

2018-05-01

The effect of an applied electric field on electronic band structure and optical absorption properties of n-doped InN0.92y P1-1.92y Bi y /InP multiple quantum wells (MQWs) was theoretically studied using a self-consistent calculation combined with the 16-band anti-crossing model. The incorporation of N and Bi atoms into an InP host matrix leads to rapid reduction of the band gap energy covering a large infrared range. The optimization of the well parameters, such as the well/barrier widths, N/Bi compositions and doping density, allowed us to obtain InN0.92y P1-1.92y Bi y /InP MQWs operating at the wavelength 1.55 μm. Application of the electric field causes a red-shift of the fundamental transition energy T 1 accompanied by a significant change in the spatial distribution of confined electron density. The Stark effect on the absorption coefficient of n-doped InN0.92y P1-1.92y Bi y /InP MQWs was investigated. The Bi composition of these MQWs was adjusted for each electric field value in order to maintain the wavelength emission at 1.55 μm.

Production and electrical parameters of La /SUB 1-x/ Ca /SUB x/ Cr /SUB 1-y/ Ni /SUB y/ O3 (x ranging from 0-0.3; y ranging from 0-1)

International Nuclear Information System (INIS)

Kononyuk, I.F.; Surmach, N.G.; Tolochko, S.P.

1986-01-01

This paper deals with the conditions for the formation of LaCr /SUB 1-y/ Ni /SUB y/ O 3 , La /SUB 1-x/ Ca /SUB x/ CrO 3 , and La /SUB 1-x/ Ca /SUB x/ Cr /SUB 1-y/ Ni /SUB y/ O 3 solid solutions and the electrical parameters of these. The initial materials were lanthanum, calcium, nickel, and chromium nitrates of pure or analytical grade. It is shown that partial replacement of lanthanum by calcium does not have any substantial effect on the electrical parameters of La /SUB 1-x/ Ca /SUB x/ Cr /SUB 1-y/ Ni /SUB y/ O 3 solid solutions for y = 0.2-0.6, but it increases the conductivity of La /SUB 1-x/ Ca /SUB x/ CrO 3 by three orders of magnitude as x varies from 0 to 0.3. The electrical parameters are virtually the same for lanthanum chromites containing calcium and strontium. The solubility of calcium in lanthanum chromite is reduced in the presence of nickel

EFECTO DEL 1-METILCICLOPROPENO (1-MCP Y TRATAMIENTO HIDROTÉRMICO SOBRE LA FISIOLOGÍA Y CALIDAD DEL MANGO 'KEITT'

Directory of Open Access Journals (Sweden)

J. A. Osuna-García

2007-01-01

Full Text Available El objetivo del presente trabajo fue evaluar el efecto del 1-MCP (0 y 300 nl·litro-1 y diferentes niveles de tratamiento hidrotérmico (0, 52 °C por 5 min y 46 °C por 110 min sobre la fisiología y calidad de mango 'Keitt'. Se analizó velocidad de respiración, pérdida de peso, firmeza, color de pulpa, sólidos solubles totales y porcentaje de frutos enfermos. Se encontró que la efectividad del 1-MCP varió acorde al nivel de tratamiento hidrotérmico. En frutos sin hidrotérmico el 1-MCP disminuyó velocidad de respiración, no influyó en la pérdida de peso, mantuvo cuatro veces más la firmeza y retrasó el cambio de color de pulpa y el aumento de los sólidos solubles. Sin embargo, bajo tratamiento hidrotérmico por 5 min el 1-MCP incrementó velocidad de respiración, no influyó en la pérdida de peso, mantuvo dos veces más la firmeza de pulpa, retrasó el desarrollo del color de pulpa y mantuvo sin cambios los sólidos solubles. La efectividad del 1-MCP sobre firmeza y pérdida de peso fue significativamente afectada por el tratamiento hidrotérmico de 110 min, y no tuvo ningún efecto sobre el control de enfermedades, sin embargo, el tratamiento con agua caliente por 5 min redujo en más de 50 % la presencia de frutos enfermos. El 1-MCP en combinación con el tratamiento hidrotérmico de 5 min alargó en cinco días la vida de anaquel de los frutos y podría ser una alternativa viable en mercados que no requieren tratamiento hidrotérmico cuarentenario para el control de mosca de la fruta.

Pseudobinary glassy compositions (AsSex)1-y(AsTex)y

International Nuclear Information System (INIS)

El Mously, M.K.; El Dem, M.B.

1987-09-01

The ternery glassy composition of the general formula (AsSe x ) 1-y (AsTe x ) y can be considered as a pseudobinary system at x=1, 3/2 and 5/2 and 0 ≤ y ≤ 1. The results of DTA, electrical conductivity measurements, density of such glasses as well as the X-ray diffraction of the crystallized samples have been used to confirm this point of view and to explain the presence of new phases not shown in the simple binary systems As-Se and As-Te. The possibility of transformation of the glassy network from partially polymerized state MCN (molecular cluster network) to completely polymerized state CRN (continuous random network) by mixing two structural units was also discussed. (author). 12 refs, 7 figs, 2 tabs

Nanopowders Y{sub 1−y}Nd{sub y}V{sub 1−x}Cr{sub x}O{sub 4} with y=0 and 1; x=0, 0.1, 0.2 and 0.5 synthesized by a sol–gel process. Relationship between morphological characteristics and optical properties

Energy Technology Data Exchange (ETDEWEB)

Alcaraz, L. [Departamento de Química Inorgánica I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Isasi, J., E-mail: isasi@quim.ucm.es [Departamento de Química Inorgánica I, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Caballero, A.C. [Departamento de Electrocerámica, Instituto de Cerámica y Vidrio (CSIC), Kelsen, 5, 28049 Madrid (Spain); Izquierdo, J.G.; Bañares, L. [Departamento de Química Física I and Centro de Láseres Ultrarrápidos, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)

2015-05-15

Y{sub 1−y}Nd{sub y}V{sub 1−x}Cr{sub x}O{sub 4} nanopowders with y=0 and 0.1; x=0, 0.1, 0.2 and 0.5, have been synthetized by a sol–gel process followed by heating in an oxygen flow. This second treatment was done only in the case of samples containing chromium. The samples have been characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structural analysis revealed that when chromium was inserted at vanadium-sites in Y{sub 0.9}Nd{sub 0.1}VO{sub 4}, the host retained the tetragonal symmetry corresponding to a zircon-type structure, attributed to the space group I4{sub 1}/amd. In addition, a loss of crystallinity was observed when chromium substitutes vanadium into the Y{sub 0.9}Nd{sub 0.1}VO{sub 4} host. The morphological studies revealed agglomerates of spherical particles whose size is increased with the Cr content and confirmed the composition of all synthetized samples. FTIR spectra of these samples exhibit a broadening and a slight shift of the bands around 830 cm{sup −1} towards higher values of frequency when the chromium content increases. The effect of vanadium substitution by chromium on the optical properties was also evaluated by UV–vis absorption and photoluminescence (PL) spectroscopies. The broad UV band absorption is due to the presence of Cr{sup 5+}. A decrease of PL emission is found when chromium substitutes vanadium in the YVO{sub 4} host. - Highlights: • Nanophosphors Y{sub 1−y}Nd{sub y}V{sub 1−x}Cr{sub x}O{sub 4} with y=0, 0.1 and x=0, 0.1, 0.2 and 0.5 have been synthesized. • Structural analysis reveals structural distortions associated to chromium insertion. • Morphological studies confirm the nanocristalline size and the stoichiometry of synthesized samples. • Chromium insertion causes a decrease of the PL emission intensity.

In vitro corrosion of Mg–1.21Li–1.12Ca–1Y alloy

Directory of Open Access Journals (Sweden)

Rongchang Zeng

2014-10-01

Full Text Available The influence of the microstructure on mechanical properties and corrosion behavior of the Mg–1.21Li–1.12Ca–1Y alloy was investigated using OM, SEM, XRD, EPMA, EDS, tensile tests and corrosion measurements. The results demonstrated that the microstructure of the Mg–1.21Li–1.12Ca–1Y alloy was characterized by α-Mg substrate and intermetallic compounds Mg2Ca and Mg24Y5. Most of the fine Mg2Ca particles for the as-cast alloy were distributed along the grain boundaries, while for the as-extruded along the extrusion direction. The Mg24Y5 particles with a larger size than the Mg2Ca particles were positioned inside the grains. The mechanical properties of Mg–1.21Li–1.12Ca–1Y alloy were improved by the grain refinement and dispersion strengthening. Corrosion pits initiated at the α-Mg matrix neighboring the Mg2Ca particles and subsequently the alloy exhibited general corrosion and filiform corrosion as the corrosion product layer of Mg(OH2 and MgCO3 became compact and thick.

Galvanomagnetic effects in n-Hg1-x-yCdxMnyTe and n-Hg1-yMnyTe crystals with εg>0

International Nuclear Information System (INIS)

Gluzman, N.G.; Lerinman, N.K.; Sabirzyanova, L.D.; Bodnaruk, O.A.; Gorbatyuk, I.N.; Rarenko, I.M.

1989-01-01

Longitudinal ρ zz and transverse ρ xx magnetoresistances and R hall coefficient in H magnetic fields up to 100 kE at 1.2≤T≤300 K are measured at n-Hg 1-x-y Cd x Mn y Te and n-Hg 1-y Mn y Te crystals (100≤ε g ≤260 meV) with N D -N A ≅10 15 cm -3 . Shubnikov-de-Gaas (SG) oscillations were observed at all specimens. Maxima positions of SG oscillations depend on T. For Hg 1-y Mn y Te crystals the position of zero maximum is shifted to large H direction, it is caused by abrupt (as compared to zone one) reduction of summary g-factor. Magnetophonon oscillations are determined at longitudinal magnetoresistance. Transition from metal conductivity to activation one occuring in magnetic field is studied; activation energy in nonmetallic range is determined. Some peculiarities of galvanomagnetic phenomena in n-Hg 1-y Mn y Te specimens, which indicate presence of p-type inclusions in n-type crystals, are determined

Fe site occupancy and superconductivity in Y1-zCazBaz(Cu1-xFex)3O6+y

International Nuclear Information System (INIS)

Smith, M.G.; Taylor, R.D.; Oesterreicher, H.

1990-01-01

X-ray diffraction and 57 Fe Moessbauer spectroscopy studies show that partial substitution of Ca for Y in Y 1-z Ca z Ba 2 (Cu 1-x Fe x ) 3 O 6+y (0.05 ≤ z ≤ 0.15,0.003 ≤ x ≤ 0.20) result in increased Fe solubility and a larger percentage of Fe occupancy of the Cu(2) plane site (prepared conventionally). Materials with z > 0.00 have a slightly depressed superconducting transition onset temperature T c relative to the z = 0.00 compounds. It is also shown that Fe occupancy of the Cu(2) site in Y 1-z Ca z Ba 2 (Cu 1-x Fe x ) 3 O 6+y can be substantially increased when these materials are treated at high temperatures in inert atmospheres followed by oxygenation at low temperatures. T c decreases more rapidly in these latter materials compared to the conventionally prepared ones. Implications concerning ordered Fe cluster formation and superconducting pair breaking in the Cu(2) site are drawn. 7 refs., 4 tabs

Nanopowders Y1−yNdyV1−xCrxO4 with y=0 and 1; x=0, 0.1, 0.2 and 0.5 synthesized by a sol–gel process. Relationship between morphological characteristics and optical properties

International Nuclear Information System (INIS)

Alcaraz, L.; Isasi, J.; Caballero, A.C.; Izquierdo, J.G.; Bañares, L.

2015-01-01

Y 1−y Nd y V 1−x Cr x O 4 nanopowders with y=0 and 0.1; x=0, 0.1, 0.2 and 0.5, have been synthetized by a sol–gel process followed by heating in an oxygen flow. This second treatment was done only in the case of samples containing chromium. The samples have been characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structural analysis revealed that when chromium was inserted at vanadium-sites in Y 0.9 Nd 0.1 VO 4 , the host retained the tetragonal symmetry corresponding to a zircon-type structure, attributed to the space group I4 1 /amd. In addition, a loss of crystallinity was observed when chromium substitutes vanadium into the Y 0.9 Nd 0.1 VO 4 host. The morphological studies revealed agglomerates of spherical particles whose size is increased with the Cr content and confirmed the composition of all synthetized samples. FTIR spectra of these samples exhibit a broadening and a slight shift of the bands around 830 cm −1 towards higher values of frequency when the chromium content increases. The effect of vanadium substitution by chromium on the optical properties was also evaluated by UV–vis absorption and photoluminescence (PL) spectroscopies. The broad UV band absorption is due to the presence of Cr 5+ . A decrease of PL emission is found when chromium substitutes vanadium in the YVO 4 host. - Highlights: • Nanophosphors Y 1−y Nd y V 1−x Cr x O 4 with y=0, 0.1 and x=0, 0.1, 0.2 and 0.5 have been synthesized. • Structural analysis reveals structural distortions associated to chromium insertion. • Morphological studies confirm the nanocristalline size and the stoichiometry of synthesized samples. • Chromium insertion causes a decrease of the PL emission intensity

LOS GENES BRCA1 y BRCA2. ESTUDIO MOLECULAR

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N. Alonso

2006-11-01

Full Text Available RESUMENEn los últimos años, se realizaron numerosos estudios para establecer la predisposición hereditaria al cáncer y las alteraciones mutacionales a nivel de genes susceptibles de originar cáncer de mama y ovario. En 1994 se identificaron los genes BRCA1 (Breast Cancer Gene 1 y BRCA2 (Breast Cancer Gene 2 como susceptibles de cáncer de mama y ovario. En la actualidad se sabe que las mutaciones en BRCA1 y BRCA2 están lejos de explicar la totalidad de los casos de cáncer de mama y/o ovario, y a pesar de que se postulan alteraciones mutacionales en otros genes como CHEK2, TP53 y PTEN, el BRCA1 y BRCA2, siguen teniendo su importancia y utilidad en la valoración del riesgo de predisposición hereditaria. Aunque las cifras son variables según los distintos estudios y autores, se trata en cualquier caso de porcentajes importantes. Entre el 15 y el 85% de las mujeres portadoras de mutación BRCA 1 o BRCA 2 tienen riesgo de desarrollar un cáncer de mama y entre un 10 y 60% de desarrollar un cáncer de ovario. ABSTRACT:In the last years, numerous studies were made to establish the hereditary predisposition to the cancer and the mutationals alterations at level of genes susceptible to originate breast and ovarian cancers. In 1994 genes BRCA1 (Breast Cancer Gene 1 and BRCA2 were identified (Breast Cancer Gene 2 as susceptible of both of breast and ovarian cancers. At the present time, it is knows that the mutations in BRCA 1 and BRCA 2 are far from explaining the totality of the cases of breast cancer and/or ovary, and although mutationals alterations in other genes like CHEK2, TP53 and PTEN, the BRCA1 and BRCA2 are postulated, they continue having his importance and utility in the valuation of the risk of hereditary predisposition. Correlations between both BRCA1 and BRCA2 levels with tumour grade metastasis and prognostic accuracy. Between 15 and 85% of the carrying women of mutation BRCA 1 or BRCA 2 have risk of developing a cancer of breast

Electrical properties of the LaLi y Co1 - y O3 - δ (0 ≤ y ≤ 0.10) oxides

Science.gov (United States)

Vecherskii, S. I.; Konopel'ko, M. A.; Batalov, N. N.; Antonov, B. D.; Reznitskikh, O. G.; Yaroslavtseva, T. V.

2017-08-01

The effect of the Li ion concentration on the phase composition, the electrical conductivity, and the thermoelectric power of the LaLi y Co1- y O3-δ (0 ≤ y ≤ 0.1) oxides synthesized by cocrystallization has been studied. It is found that the region of the perovskite-like solid solution LaLi y Co1- y O3-δ is no higher than y = 0.037. In the temperature range 300-1020 K, lithium alloying leads to an increase in the electrical conductivity and a decrease in the positive thermoelectric power of the single-phase samples compared to LaCoO3-δ. The results are discussed using the density of states model proposed by Senarus Rodriguez and Goodenough for LaCoO3-δ and La1- x Sr x CoO3-δ and using the Mott theory of noncrystalline substances.

Oligo-DNA custom macroarray for monitoring major pathogenic and non-pathogenic fungi and bacteria in the phyllosphere of apple trees.

Science.gov (United States)

He, Ying-Hong; Isono, Sayaka; Shibuya, Makoto; Tsuji, Masaharu; Adkar Purushothama, Charith-Raj; Tanaka, Kazuaki; Sano, Teruo

2012-01-01

To monitor the richness in microbial inhabitants in the phyllosphere of apple trees cultivated under various cultural and environmental conditions, we developed an oligo-DNA macroarray for major pathogenic and non-pathogenic fungi and bacteria inhabiting the phyllosphere of apple trees. First, we isolated culturable fungi and bacteria from apple orchards by an agar-plate culture method, and detected 32 fungal and 34 bacterial species. Alternaria, Aureobasidium, Cladosporium, Rhodotorula, Cystofilobasidium, and Epicoccum genera were predominant among the fungi, and Bacillus, Pseudomonas, Sphingomonas, Methylobacterium, and Pantoea genera were predominant among the bacteria. Based on the data, we selected 29 major non-pathogenic and 12 phytopathogenic fungi and bacteria as the targets of macroarray. Forty-one species-specific 40-base pair long oligo-DNA sequences were selected from the nucleotide sequences of rDNA-internal transcribed spacer region for fungi and 16S rDNA for bacteria. The oligo-DNAs were fixed on nylon membrane and hybridized with digoxigenin-labeled cRNA probes prepared for each species. All arrays except those for Alternaria, Bacillus, and their related species, were specifically hybridized. The array was sensitive enough to detect 10(3) CFU for Aureobasidium pullulans and Bacillus cereus. Nucleotide sequencing of 100 each of independent fungal rDNA-ITS and bacterial 16S-rDNA sequences from apple tree was in agreement with the macroarray data obtained using the same sample. Finally, we analyzed the richness in the microbial inhabitants in the samples collected from apple trees in four orchards. Major apple pathogens that cause scab, Alternaria blotch, and Marssonina blotch were detected along with several non-phytopathogenic fungal and bacterial inhabitants. The macroarray technique presented here is a strong tool to monitor the major microbial species and the community structures in the phyllosphere of apple trees and identify key species

Oligo-DNA custom macroarray for monitoring major pathogenic and non-pathogenic fungi and bacteria in the phyllosphere of apple trees.

Directory of Open Access Journals (Sweden)

Ying-Hong He

Full Text Available BACKGROUND: To monitor the richness in microbial inhabitants in the phyllosphere of apple trees cultivated under various cultural and environmental conditions, we developed an oligo-DNA macroarray for major pathogenic and non-pathogenic fungi and bacteria inhabiting the phyllosphere of apple trees. METHODS AND FINDINGS: First, we isolated culturable fungi and bacteria from apple orchards by an agar-plate culture method, and detected 32 fungal and 34 bacterial species. Alternaria, Aureobasidium, Cladosporium, Rhodotorula, Cystofilobasidium, and Epicoccum genera were predominant among the fungi, and Bacillus, Pseudomonas, Sphingomonas, Methylobacterium, and Pantoea genera were predominant among the bacteria. Based on the data, we selected 29 major non-pathogenic and 12 phytopathogenic fungi and bacteria as the targets of macroarray. Forty-one species-specific 40-base pair long oligo-DNA sequences were selected from the nucleotide sequences of rDNA-internal transcribed spacer region for fungi and 16S rDNA for bacteria. The oligo-DNAs were fixed on nylon membrane and hybridized with digoxigenin-labeled cRNA probes prepared for each species. All arrays except those for Alternaria, Bacillus, and their related species, were specifically hybridized. The array was sensitive enough to detect 10(3 CFU for Aureobasidium pullulans and Bacillus cereus. Nucleotide sequencing of 100 each of independent fungal rDNA-ITS and bacterial 16S-rDNA sequences from apple tree was in agreement with the macroarray data obtained using the same sample. Finally, we analyzed the richness in the microbial inhabitants in the samples collected from apple trees in four orchards. Major apple pathogens that cause scab, Alternaria blotch, and Marssonina blotch were detected along with several non-phytopathogenic fungal and bacterial inhabitants. CONCLUSIONS: The macroarray technique presented here is a strong tool to monitor the major microbial species and the community structures in

Observation of spin reorientation in layered manganites La1.2Sr1.8(Mn1-yRuy)2O7 (0.0=<y=<0.2) by Lorentz transmission electron microscopy

International Nuclear Information System (INIS)

Yu, X.Z.; Uchida, M.; Onose, Y.; He, J.P.; Kaneko, Y.; Asaka, T.; Kimoto, K.; Matsui, Y.; Arima, T.; Tokura, Y.

2006-01-01

The effect of Ru substitution for Mn in bilayered oxides La 1.2 Sr 1.8 (Mn 1-y Ru y ) 2 O 7 (0= for the y=0 crystal to the c-axis for y=0.2, and it rotates away from the c-axis for the y=0.05 and y=0.07 crystals with decreasing temperature. Furthermore, maze-shaped magnetic domain structures were observed in the (001) thin crystals with 0.05=< y=<0.2. Changes in domain size and structure indicate that the uniaxial magnetic anisotropy becomes stronger as Ru content y increases

Fungal contaminants in man-made water systems connected to municipal water.

Science.gov (United States)

Kadaifciler, Duygu Göksay; Demirel, Rasime

2018-04-01

Water-related fungi are known to cause taste and odor problems, as well as negative health effects, and can lead to water-pipeline clogging. There is no legal regulation on the occurrence of fungi in water environments. However, much research has been performed, but further studies are needed. The main objectives of this study were to evaluate the fungal load and the presence of mycotoxigenic fungi in man-made water systems (for homes, hospitals, and shopping centers) connected to municipal water in Istanbul, Turkey. The mean fungal concentrations found in the different water samples were 98 colony-forming units (CFU)/100 mL in shopping centers, 51 CFU/100 mL in hospitals, and 23 CFU/100 mL in homes. The dominant fungal species were identified as Aureobasidium pullulans and Fusarium oxysporum. Aflatoxigenic Aspergillus flavus and ochratoxigenic Aspergillus westerdijkiae were only detected in the hospital water samples. Alternaria alternata, Aspergillus clavatus, Aspergillus fumigatus, and Cladosporium cladosporioides were also detected in the samples. The study reveals that the municipal water supplies, available for different purposes, could thus contain mycotoxigenic fungi. It was concluded that current disinfection procedures may be insufficient, and the presence of the above-mentioned fungi is important for people with suppressed immune systems.

Microglia P2Y13 Receptors Prevent Astrocyte Proliferation Mediated by P2Y1 Receptors

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Clara Quintas

2018-05-01

Full Text Available Cerebral inflammation is a common feature of several neurodegenerative diseases that requires a fine interplay between astrocytes and microglia to acquire appropriate phenotypes for an efficient response to neuronal damage. During brain inflammation, ATP is massively released into the extracellular medium and converted into ADP. Both nucleotides acting on P2 receptors, modulate astrogliosis through mechanisms involving microglia-astrocytes communication. In previous studies, primary cultures of astrocytes and co-cultures of astrocytes and microglia were used to investigate the influence of microglia on astroglial proliferation induced by ADPβS, a stable ADP analog. In astrocyte cultures, ADPβS increased cell proliferation through activation of P2Y1 and P2Y12 receptors, an effect abolished in co-cultures (of astrocytes with ∼12.5% microglia. The possibility that the loss of the ADPβS-mediated effect could have been caused by a microglia-induced degradation of ADPβS or by a preferential microglial localization of P2Y1 or P2Y12 receptors was excluded. Since ADPβS also activates P2Y13 receptors, the contribution of microglial P2Y13 receptors to prevent the proliferative effect of ADPβS in co-cultures was investigated. The results obtained indicate that P2Y13 receptors are low expressed in astrocytes and mainly expressed in microglia. Furthermore, in co-cultures, ADPβS induced astroglial proliferation in the presence of the selective P2Y13 antagonist MRS 2211 (3 μM and of the selective P2Y12 antagonist AR-C66096 (0.1 μM, suggesting that activation of microglial P2Y12 and P2Y13 receptors may induce the release of messengers that inhibit astroglial proliferation mediated by P2Y1,12 receptors. In this microglia-astrocyte paracrine communication, P2Y12 receptors exert opposite effects in astroglial proliferation as a result of its cellular localization: cooperating in astrocytes with P2Y1 receptors to directly stimulate proliferation and in

Regulation of P2Y1 receptor traffic by sorting Nexin 1 is retromer independent.

Science.gov (United States)

Nisar, Shaista; Kelly, Eamonn; Cullen, Pete J; Mundell, Stuart J

2010-04-01

The activity and traffic of G-protein coupled receptors (GPCRs) is tightly controlled. Recent work from our laboratory has shown that P2Y(1) and P2Y(12) responsiveness is rapidly and reversibly modulated in human platelets and that the underlying mechanism requires receptor trafficking as an essential part of this process. However, little is known about the molecular mechanisms underlying P2Y receptor traffic. Sorting nexin 1 (SNX1) has been shown to regulate the endosomal sorting of cell surface receptors either to lysosomes where they are downregulated or back to the cell surface. These functions may in part be due to interactions of SNX1 with the mammalian retromer complex. In this study, we investigated the role of SNX1 in P2Y receptor trafficking. We show that P2Y(1) receptors recycle via a slow recycling pathway that is regulated by SNX1, whereas P2Y(12) receptors return to the cell surface via a rapid route that is SNX1 independent. SNX1 inhibition caused a dramatic increase in the rate of P2Y(1) receptor recycling, whereas inhibition of Vps26 and Vps35 known to be present in retromer had no effect, indicating that SNX1 regulation of P2Y(1) receptor recycling is retromer independent. In addition, inhibition of SNX4, 6 and 17 proteins did not affect P2Y(1) receptor recycling. SNX1 has also been implicated in GPCR degradation; however, we provide evidence that P2Y receptor degradation is SNX1 independent. These data describe a novel function of SNX1 in the regulation of P2Y(1) receptor recycling and suggest that SNX1 plays multiple roles in endocytic trafficking of GPCRs.

Y1 receptors for neuropeptide Y are coupled to mobilization of intracellular calcium and inhibition of adenylate cyclase

DEFF Research Database (Denmark)

Aakerlund, L; Gether, U; Fuhlendorff, J

1990-01-01

Two types of binding sites have previously been described for neuropeptide Y (NPY), called Y1 and Y2 receptors. The intracellular events following Y1 receptor activation was studied in the human neuroblastoma cell line SK-N-MC. Both NPY and the specific Y1 receptor ligand, [Leu31,Pro34]-NPY, caused...

Site Environmental Report for 2010, Volumes 1 & 2

Energy Technology Data Exchange (ETDEWEB)

Baskin, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bauters, Tim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Borglin, Ned [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fox, Robert [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Horst, Blair [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jelinski, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lackner, Ginny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Philliber, Jeff [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rothermich, Nancy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Thorson, Patrick [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wahl, Linnea [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Xu, Suying [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2011-09-01

LBNL is a multiprogram scientific facility operated by the UC for the DOE. LBNL’s research is directed toward the physical, biological, environmental, and computational sciences, in order to deliver scientific knowledge and discoveries pertinent to DOE’s missions. This annual Site Environmental Report covers activities conducted in CY 2010. The format and content of this report satisfy the requirements of DOE Order 231.1A, Environment, Safety, and Health Reporting,1 and the operating contract between UC and DOE

49 CFR 231.3 - Drop-end high-side gondola cars.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Drop-end high-side gondola cars. 231.3 Section 231... gondola cars. (a) Hand brakes—(1) Number. Same as specified for “Box and other house cars” (see § 231.1(a)(1)). (2) Dimensions. Same as specified for “Box and other house cars” (see § 231.1(a)(2)). (3...

49 CFR 231.5 - Drop-end low-side gondola cars.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Drop-end low-side gondola cars. 231.5 Section 231... gondola cars. (a) Hand brakes—(1) Number. Same as specified for “Box and other house cars” (see § 231.1(a)(1)). (2) Dimensions. Same as specified for “Box and other house cars” (see § 231.1(a)(2)). (3...

Transport properties of the LiNi{sub 1-y}Co{sub y}O{sub 2} system

Energy Technology Data Exchange (ETDEWEB)

Molenda, J.; Wilk, P.; Marzec, J. [Department of Solid State Chemistry, Stanislaw Staszic University of Mining and Metallurgy, Al. A. Mickiewicza 30, 30-059 Cracow (Poland)

1999-04-15

In this paper results are presented concerning structure, electrical conductivity and thermoelectric power measurements of the LiNi{sub 1-y}Co{sub y}O{sub 2} system. It has been stated that holes are dominating carriers. It has been also found that cobalt worsens the transport properties of the LiNi{sub 1-y}Co{sub y}O{sub 2} system

[Diversity and community structure of endophytic fungi from Taxus chinensis var. mairei].

Science.gov (United States)

2014-07-01

A total of 628 endophytic fungi were isolated from 480 tissue segments of needles and branches of Taxus chinensis var. mairei. According to morphological characteristics and ITS sequences, they represented 43 taxa in 28 genera, of which 10 Hyphomycetes, 20 Coelomycetes, 12 Ascomycetes and 1 unknown fungus. Phomopsis mali was confirmed as the dominant species. In accordance with relative frequency, Alternaria alternata, Aureobasidium pullulans, Colletotrichum boninense, C. gloeosporioides, Epicoccum nigrum , Fungal sp., Fusarium lateritium, Glomerella cingulata, Magnaporthales sp. , Nigrospora oryzae, Pestalotiopsis maculiformans, P. microspora, Peyronellaea glomerata and Xylaria sp. 1 were more common in T. chinensis var. mairei. T. chinensis var. mairei were severely infected by endophytic fungi. Endophytic fungi were found in 81 percent of plant tissues with a high diversity. Distribution ranges of endophytic fungi were influenced by tissue properties. The colonization rate, richness, diversity of endophytic fungi in needles were obviously lower than in branches, and kinds of endophytic fungi between branches were more similar than those in needles, thus endophytic fungi had tissue preference. In addition, tissue age influenced the community structure of endophytic fungi. The elder branch tissues were, the higher colonization rate, richness, diversity of endophytic fungi were. Systematic studying the diversity and community structure of endophytic fungi in T. chinensis var. mairei and clarifying their distribution regularity in plant tissues would offer basic data and scientific basis for their development and utilization. Discussing the presence of fungal pathogens in healthy plant tissues would be of positive significance for source protection of T. chinensis var. mairei.

ISOMERIZACIÓN DEL 1-CICLOHEXILOCTANO EN ZEOLITAS H-ZSM-22 Y H-Y

Directory of Open Access Journals (Sweden)

Jorge Quintero

2009-06-01

Full Text Available En este trabajo presentamos los resultados de la evaluacion energetica de los intermediarios de la isomerización del 1-ciclohexiloctano en dos etapas. La primera etapa corresponde a la isomerización del 1-ciclohexiloctano en fase gaseosa vía carbocationes clásicos, usando el nivel de teoría DFT/B3LYP y conjunto de funciones base 6-31G.  En la segunda etapa se desarrolló la coordenada de reacción de la isomerización del 1-ciclohexiloctano en presencia de zeolitas ácidas H-ZSM-22 y H-Y empleando el método ONIOM, usando los niveles de teoría B3LYP/6-31G:UFF. Nuestros resultados muestran diferencias significativas entre las reacciones en fase gaseosa y condensada. Estas diferencias ponen de manifiesto la influencia del confinamiento cuántico que sufren las moléculas al interior de los sistemas microporosos del tipo zeolitas.

Silica-supported tungsten carbynes (≡SiO)xW(≡CH)(Me)y (x = 1, y = 2; X = 2, y = 1): New efficient catalysts for alkyne cyclotrimerization

KAUST Repository

Riache, Nassima

2015-02-23

The activity of silica-supported tungsten carbyne complexes (≡SiO)xW(≡CH)(Me)y (x = 1, y = 2; x = 2, y = 1) toward alkynes is reported. We found that they are efficient precatalysts for terminal alkyne cyclotrimerization with high TONs. We also demonstrate that this catalyst species is active for alkyne cyclotrimerization without the formation of significant alkyne metathesis products. Additional DFT calculations highlight the importance of the W coordination sphere in supporting this experimental behavior.

Stability of Cd_1_–_xZn_xO_yS_1_–_y Quaternary Alloys Assessed with First-Principles Calculations

International Nuclear Information System (INIS)

Varley, Joel B.; He, Xiaoqing; Rockett, Angus; Lordi, Vincenzo

2017-01-01

One route to decreasing the absorption in CdS buffer layers in Cu(In,Ga)Se_2 and Cu_2ZnSn(S,Se)_4 thin-film photovoltaics is by alloying. Here we use first-principles calculations based on hybrid functionals to assess the energetics and stability of quaternary Cd, Zn, O, and S (Cd_1_–_xZn_xO_yS_1_–_y) alloys within a regular solution model. Our results identify that full miscibility of most Cd_1_–_xZn_xO_yS_1_–_y compositions and even binaries like Zn(O,S) is outside typical photovoltaic processing conditions. Finally, the results suggest that the tendency for phase separation of the oxysulfides may drive the nucleation of other phases such as sulfates that have been increasingly observed in oxygenated CdS and ZnS.

Thermoelectric properties of p-type Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2}

Energy Technology Data Exchange (ETDEWEB)

Ahn, Kyunghan [Department of Chemistry, Northwestern University, Evanston, IL 60208 (United States); Center for Nanoparticle Research, Institute for Basic Science, (IBS), Seoul 151-742 (Korea, Republic of); Kong, Huijun; Uher, Ctirad [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Kanatzidis, Mercouri G., E-mail: m-kanatzidis@northwestern.edu [Department of Chemistry, Northwestern University, Evanston, IL 60208 (United States)

2016-10-15

The thermoelectric properties of Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} (4≤m≤16, −0.1≤x≤0.3, 1/3≤y≤2/3, 0.2≤z≤0.4; Lead Antimony Silver Tellurium Tin, LASTT-m) compositions were investigated in the temperature range of 300 to ~670 K. All samples crystallize in the average NaCl-type structure without any noticeable second phase and exhibit very narrow bandgaps of <0.1 eV. We studied a range of m values, silver concentrations (x), Pb/Sn ratios (y), and antimony concentrations (z) to determine their effects on the thermoelectric properties. The samples were investigated as melt grown polycrystalline ingots. Varying the Ag contents, the Pb/Sn ratios, and the Sb contents off-stoichiometry allowed us to control the electrical conductivity, the Seebeck coefficient, and the thermal conductivity. The electrical conductivity tends to decrease with decreasing m values. The highest ZT of ~1.1 was achieved at ~660 K for Ag{sub 0.9}Pb{sub 5}Sn{sub 5}Sb{sub 0.8}Te{sub 12} mainly due to the very low lattice thermal conductivity of ~0.4 W/(m K) around 660 K. Also, samples with charge-balanced stoichiometries, Ag(Pb{sub 1−y}Sn{sub y}){sub m}SbTe{sub m+2}, were studied and found to exhibit a lower power factor and higher lattice thermal conductivity than the Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} compositions. - Graphical abstract: The Ag{sub 1−x}(Pb{sub 1−y}Sn{sub y}){sub m}Sb{sub 1−z}Te{sub m+2} system defines a complex and flexible class of tunable thermoelectric class of materials with high performance.

Control of Co content and SOFC cathode performance in Y1-ySr2+yCu3-xCoxO7+δ

Science.gov (United States)

Šimo, F.; Payne, J. L.; Demont, A.; Sayers, R.; Li, Ming; Collins, C. M.; Pitcher, M. J.; Claridge, J. B.; Rosseinsky, M. J.

2014-11-01

The electrochemical performance of the layered perovskite YSr2Cu3-xCoxO7+δ, a potential solid oxide fuel cell (SOFC) cathode, is improved by increasing the Co content from x = 1.00 to a maximum of x = 1.30. Single phase samples with x > 1.00 are obtained by tuning the Y/Sr ratio, yielding the composition Y1-ySr2+yCu3-xCoxO7+δ (where y ≤ 0.05). The high temperature structure of Y0.95Sr2.05Cu1.7Co1.3O7+δ at 740 °C is characterised by powder neutron diffraction and the potential of this Co-enriched material as a SOFC cathode is investigated by combining AC impedance spectroscopy, four-probe DC conductivity and powder XRD measurements to determine its electrochemical properties along with its thermal stability and compatibility with a range of commercially available electrolytes. The material is shown to be compatible with doped ceria electrolytes at 900 °C.

Estudio experimental y teórico de mezclas líquidas binarias formadas por 1-alcoholes y ciclohexilamina

OpenAIRE

Sanz del Soto, Luis Felipe

2016-01-01

Mediante la medida experimental de la densidad, viscosidad, índice de refracción y permitividad a tres temperaturas (293.15, 298.15 y 303.15 K) y el cálculo de diferentes magnitudes derivadas, se ha procedido a estudiar las interacciones intermoleculares que se producen en las mezclas líquidas binarias de 1-alcohol (metanol, 1-propanol, 1-butanol, 1-heptanol y 1-decanol) con la ciclohexilamina. Departamento de Física Aplicada Doctorado en Física

Analytical representation of the thermal conductivity and electrical resistivity of UC/sub 1 +- x/, PuC/sub 1-x/, and (U/sub y/Pu/sub 1-y/)C/sub 1 +- x/

International Nuclear Information System (INIS)

Storms, E.K.

1982-12-01

This report uses selected measurements from the literature to construct analytical expressions that describe the electrical and thermal conductivity of pure, high-density UC/sub 1 +- x/, PuC/sub 1-x/, and (U/sub y/Pu/sub 1-y/C/sub 1 +- x/ as a function of x,y, and temperature. The approach shows that many of the differences between the reported measurements can be resolved if the carbon cntent of the single-phase material is taken into account. Analytical expressions are also given that describe the temperature variation of the phase boundaries for these phases. 16 figures

Ghrelin interacts with neuropeptide Y Y1 and opioid receptors to increase food reward.

Science.gov (United States)

Skibicka, Karolina P; Shirazi, Rozita H; Hansson, Caroline; Dickson, Suzanne L

2012-03-01

Ghrelin, a stomach-derived hormone, is an orexigenic peptide that was recently shown to potently increase food reward behavior. The neurochemical circuitry that links ghrelin to the mesolimbic system and food reward behavior remains unclear. Here we examined the contribution of neuropeptide Y (NPY) and opioids to ghrelin's effects on food motivation and intake. Both systems have well-established links to the mesolimbic ventral tegmental area (VTA) and reward/motivation control. NPY mediates the effect of ghrelin on food intake via activation of NPY-Y1 receptor (NPY-Y1R); their connection with respect to motivated behavior is unexplored. The role of opioids in any aspect of ghrelin's action on food-oriented behaviors is unknown. Rats were trained in a progressive ratio sucrose-induced operant schedule to measure food reward/motivation behavior. Chow intake was measured immediately after the operant test. In separate experiments, we explored the suppressive effects of a selective NPY-Y1R antagonist or opioid receptor antagonist naltrexone, injected either intracerebroventricularly or intra-VTA, on ghrelin-induced food reward behavior. The ventricular ghrelin-induced increase in sucrose-motivated behavior and chow intake were completely blocked by intracerebroventricular pretreatment with either an NPY-Y1R antagonist or naltrexone. The intra-VTA ghrelin-induced sucrose-motivated behavior was blocked only by intra-VTA naltrexone. In contrast, the intra-VTA ghrelin-stimulated chow intake was attenuated only by intra-VTA NPY-Y1 blockade. Finally, ghrelin infusion was associated with an elevated VTA μ-opioid receptor expression. Thus, we identify central NPY and opioid signaling as the necessary mediators of food intake and reward effects of ghrelin and localize these interactions to the mesolimbic VTA.

Purification and characterization of a novel plantaricin, KL-1Y, from Lactobacillus plantarum KL-1.

Science.gov (United States)

Rumjuankiat, Kittaporn; Perez, Rodney Horanda; Pilasombut, Komkhae; Keawsompong, Suttipun; Zendo, Takeshi; Sonomoto, Kenji; Nitisinprasert, Sunee

2015-06-01

Three bacteriocins from Lactobacillus plantarum KL-1 were successfully purified using ammonium sulfate precipitation, cation-exchange chromatography and reverse-phase HPLC. The bacteriocin peptides KL-1X, -1Y and -1Z had molecular masses of 3053.82, 3498.16 and 3533.16 Da, respectively. All three peptides were stable at pH 2-12 and 25 °C and at high temperatures of 80 and 100 °C for 30 min and 121 °C for 15 min. However, they differed in their susceptibility to proteolytic enzymes and their inhibition spectra. KL-1Y showed broad inhibitory activities against Gram-positive and Gram-negative bacteria, including Salmonella enterica serovar Enteritidis DMST 17368, Pseudomonas aeruginosa ATCC 15442, P. aeruginosa ATCC 9027, Escherichia coli O157:H7 and E. coli ATCC 8739. KL-1X and -1Z inhibited only Gram-positive bacteria. KL-1X, KL-1Y and KL-1Z exhibited synergistic activity. The successful amino acid sequencing of KL-1Y had a hydrophobicity of approximately 30 % and no cysteine residues suggested its novelty, and it was designated "plantaricin KL-1Y". Plantaricin KL-1Y exhibited bactericidal activity against Bacillus cereus JCM 2152(T). Compared to nisin, KL-1Y displayed broad inhibitory activities of 200, 800, 1600, 800, 400 and 400 AU/mL against the growth of Bacillus coagulans JCM 2257(T), B. cereus JCM 2152(T), Listeria innocua ATCC 33090(T), Staphylococcus aureus TISTR 118, E. coli O157:H7 and E. coli ATCC 8739, respectively, whereas nisin had similar activities against only B. coagulans JCM 2257(T) and B. cereus JCM 2152(T). Therefore, the novel plantaricin KL-1Y is a promising antimicrobial substance for food safety uses in the future.

Conocimientos y prácticas sobre la nueva influenza A (H1N1 en trabajadores de salud y pacientes ambulatorios, Perú (mayo 2009

Directory of Open Access Journals (Sweden)

Jeannette Ávila

2009-07-01

Full Text Available Con el objetivo de determinar el nivel de conocimientos, las actitudes y prácticas de los pacientes y del personal de salud a inicios de la pandemia de la nueva Influenza A H1N1, desarrollamos un estudio descriptivo de corte transversal en establecimientos del Ministerio de Salud del Perú (MINSA sobre 313 usuarios y 244 trabajadores de 4 ciudades del país. El 38% de los pacientes encuestados asocia la nueva Influenza A (H1N1 con los cerdos o aves, un 17% no reconoce que la transmisión es de persona a persona, asimismo, entre el 35% a 50% utiliza la mano para cubrirse nariz y boca al estornudar o toser y no tiene práctica de higiene de manos. En el caso del personal de salud, el 99% advierte la transmisión humana y el 86% conoce la definición de caso sospechoso de Influenza A (H1N1. Entre el 83% y 95% de los trabajadores encuestados reconocen las medidas de protección individual recomendadas por el MINSA. En ambos grupos la televisión es el medio más visto (60% y por dónde recibe mayor información sobre Influenza A (H1N1, además, en los trabajadores de salud, un medio frecuente de información sobre el tema también es el internet (11%.

Grewia Gum 1: Some Mechanical and Swelling Properties of ...

African Journals Online (AJOL)

Erah

Methods: Compacts (500 mg) of both freeze-dried and air-dried grewia gum were separately ... grewia gum films were compared with films of pullulan and guar gum which were similarly prepared. .... Freeze-drying was carried out using an.

The marine isotope stage 1-5 cryptotephra record of Tenaghi Philippon, Greece: Towards a detailed tephrostratigraphic framework for the Eastern Mediterranean region

Science.gov (United States)

Wulf, Sabine; Hardiman, Mark J.; Staff, Richard A.; Koutsodendris, Andreas; Appelt, Oona; Blockley, Simon P. E.; Lowe, J. John; Manning, Christina J.; Ottolini, Luisa; Schmitt, Axel K.; Smith, Victoria C.; Tomlinson, Emma L.; Vakhrameeva, Polina; Knipping, Maria; Kotthoff, Ulrich; Milner, Alice M.; Müller, Ulrich C.; Christanis, Kimon; Kalaitzidis, Stavros; Tzedakis, Polychronis C.; Schmiedl, Gerhard; Pross, Jörg

2018-04-01

The iconic climate archive of Tenaghi Philippon (TP), NE Greece, allows the study of short-term palaeoclimatic and environmental change throughout the past 1.3 Ma. To provide high-quality age control for detailed palaeoclimate reconstructions based on the TP archive, (crypto)tephra studies of a peat core 'TP-2005' have been carried out for the 0-130 ka interval. The results show that the TP basin is ideally positioned to receive tephra fall from both the Italian and Aegean Arc volcanic provinces. Two visible tephra layers, the Santorini Cape Riva/Y-2 (c. 22 ka) and the Campanian Ignimbrite (CI)/Y-5 (c. 39.8 ka) tephras, and six primary cryptotephra layers, namely the early Holocene E1 tephra from the Aeolian Islands (c. 8.3 ka), the Campanian Y-3 (c. 29 ka) and X-6 tephras (c. 109.5 ka), as well as counterpart tephras TM-18-1d (c. 40.4 ka), TM-23-11 (c. 92.4 ka) and TM-33-1a (c. 116.7 ka) from the Lago Grande di Monticchio sequence (southern Italy), were identified along with repeatedly redeposited Y-2 and CI tephra material. Bayesian modelling of the ages of seven of the primary tephra layers, 60 radiocarbon measurements and 20 palynological control points have been applied to markedly improve the chronology of the TP archive. This revised chronology constrains the age of tephra TM-18-1d to 40.90-41.66 cal ka BP (95.4% range). Several tephra layers identified in the TP record form important isochrons for correlating this archive with other terrestrial (e.g., Lago Grande di Monticchio, Sulmona Basin and Lake Ohrid) and marine (e.g., Adriatic Sea core PRAD 1-2 and Aegean Sea core LC21) palaeoclimate records in the Mediterranean region.

Agonist-induced desensitization of adenylyl cyclase in Y1 adrenocortical tumor cells

International Nuclear Information System (INIS)

Olson, M.F.; Tsao, J.; Pon, D.J.; Schimmer, B.P.

1991-01-01

Y1 adrenocortical tumor cells (Y1DS) and Y1 mutants resistant to ACTH-induced desensitization of adenylyl cyclase (Y1DR) were transfected with a gene encoding the mouse beta 2-adrenergic receptor (beta 2-AR). Transfectants expressed beta 2-ARs that were able to stimulate adenylyl cyclase activity and steroid biosynthesis. These transfectants were used to explore the basis for the DR mutation in Y1 cells. The authors demonstrate that beta-adrenergic agonists desensitize the adenylyl cyclase system in transfected Y1DS cells whereas transfected Y1DR cells are resistant to desensitization by beta-adrenergic agonists. The fate of the beta 2-ARs during desensitization was evaluated by photoaffinity labelling with [125I]iodocyanopindolol diazerine. Desensitization of Y1DS transfectants was accompanied by a modest loss in receptor density that was insufficient to account for the complete loss of responsiveness to beta-adrenergic agonists. The extent of receptor loss induced by beta-adrenergic agonists in Y1DR transfectants exceeded that in the Y1DS transfectants indicating that the mutation which protects Y1DR cells from agonist-induced desensitization is prior to receptor down-regulation in the desensitization pathway. From these results we infer that ACTH and isoproterenol desensitize adenylyl cyclase by a common pathway and that receptor loss is not a major component of the desensitization process in these cells

Thermoelectric properties of Ca1-xYxMnO3 and Ca0.9Y0.1-yFeyMnO3 perovskite compounds

DEFF Research Database (Denmark)

Thuy, Nguyen Thi; Minh, Dang Le; Van Nong, Ngo

2012-01-01

Polycrystalline Ca1-xYxMnO3 (x = 0.0; 0.1; 0.3; 0.5; 0.7) and Ca0.9Y0.1-yFeyMnO3 (y = 0.00; 0.01; 0.03; 0.05) compounds were prepared by solid-state reaction. X-ray diffraction (XRD) analysis revealed all XRD peaks of all the samples as identical to the orthorhombic structure. The thermoelectric ...

On the simultaneous Pell equations x 2 - (4m 2 - 1)y 2 = y 2 - pz 2 ...

African Journals Online (AJOL)

Let m be a positive integer, and let p be an odd prime. By using certain properties of Pell and quartic diophantine equations with some elementary number theory methods, we prove that the system of equations x2 - (4m2 - 1)y2 = 1 and y2 - pz2 = 1 has positive integer solutions (x, y, z) if and only if p ≡ 7(mod 8) and m = 1/4 ...

Comparación productiva de vacas holstein y F1 blanco orejinero (BON x holstein 1. producción y calidad de la leche.

Directory of Open Access Journals (Sweden)

Quijano Bernal Jorge H.

2000-12-01

Full Text Available Se estimaron los porcentajes de heterosis para la producción de leche, duración de la lactancia y calidad de la leche ( porcentaje de grasa y proteína, en vacas Holstein y F1 (BON x HOLSTEIN del Centro Paysandú, propiedad de la Universidad Nacional de Colombia, situado en el corregimiento Santa Elena, municipio de Medellín, a 2600 m.s.n.m., con temperatura promedio de 12,5C, correspondiendo a la formación bosque muy húmedo montano bajo (bmh-MB. La producción de leche fue afectada significativamente (P 0,01 y proteína (2,8 y 2,9%; P >0,01 para Holstein y F1 BON x Holstein respectivamente. En el BON estos valores fueron 278 kg, 114 días de lactancia, 4,6% de grasa y 3,9% de proteína en la leche. Los porcentajes de heterosis con base en el promedio de razas fueron: 4,20%, 16,70%, -12,80% y -12.20% para producción de leche, duración de lactancia, porcentaje de grasa y porcentaje de proteína respectivamente, todos altamente significativos (P<0,01. Los porcentajes de heterosis tomando como referencia la raza Holstein fueron: -45,20%, -21,50%, 6,25% y 5,35% en el mismo orden de las características anteriormente citadas. En general, los porcentajes de heterosis fueron menores a los reportados en la literatura. Se concluye que el F1 ha desempeñado un papel preponderante en el mejoramiento de la calidad de la leche en el Centro Paysandú, presentado porcentajes de heterosis medios para la calidad de la leche con referencia a la raza Holstein. Esto puede ser confirmado al analizar el porcentaje de grasa desde 1994, cuando parieron las primeras vacas F1, presentado coeficiente de regresión y correlación de 0,02 y 0,55 respectivamente. En la actualidad, el promedio para el porcentaje de grasa y proteína en el hato es de 3,45% y 3,03% respectivamente. Si sólo se tuviese la raza Holstein, estos porcentajes serían de 3,20% y 2,80%, significativamente menores.

Theoretical investigations on magnetocaloric effect in Er{sub 1−y}Tb{sub y}Al{sub 2} series

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, P.O., E-mail: paula.ribeiro@gmail.com [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil); Alho, B.P.; Alvarenga, T.S.T.; Nóbrega, E.P.; Sousa, V.S.R. de [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil); Carvalho, A. Magnus G. [Laboratório Nacional de Luz Síncrotron, CNPEM, 13083-970 Campinas, SP (Brazil); Caldas, A. [Sociedade Unificada de Ensino Superior e Cultura, SUESC, 20211-351 Rio de Janeiro, RJ (Brazil); Oliveira, N.A. de; Ranke, P.J. von [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil)

2015-04-01

We report on the magnetic and magnetocaloric effect calculations in rare earth Er{sub 1−y}Tb{sub y}Al{sub 2} compounds (y=0.00, 0.25, 0.5, 0.75 and 1.00). Our model Hamiltonian has contributions of the crystalline electrical field anisotropy in both Er and Tb magnetic sublattices, disorder in exchange interactions among Er–Er, Tb–Tb and Er–Tb magnetic ions and the Zeeman effect. The magnetization, the isothermal entropy change (ΔS{sub T}) and the adiabatic temperature change (ΔT{sub ad}) dependence on temperature were simulated and, compared with the experimental data available. - Highlights: • Modeling Er{sub (1−y)}Tb{sub y}Al{sub 2} intermetallic compounds. • Magnetic entropy changes in Er{sub (1−y)}Tb{sub y}Al{sub 2}. • Adiabatic temperature changes in Er{sub 0.75}Tb{sub 0.25}Al{sub 2} and Er{sub 0.65}Tb{sub 0.35}Al{sub 2} compounds.

Immobilized Burkholderia cepacia Lipase on pH-Responsive Pullulan Derivatives with Improved Enantioselectivity in Chiral Resolution

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Li Xu

2018-01-01

Full Text Available A kind of pH-responsive particle was synthesized using modified pullulan polysaccharide. The synthesized particle possessed a series of merits, such as good dispersity, chemical stability and variability of particle size, making it a suitable carrier for enzyme immobilization. Then, Burkholderia cepacia lipase (BCL, a promising biocatalyst in transesterification reaction, was immobilized on the synthesized particle. The highest catalytic activity and immobilization efficiency were achieved at pH 6.5 because the particle size was obviously enlarged and correspondingly the adsorption surface for BCL was significantly increased. The immobilization enzyme loading was further optimized, and the derivative lipase was applied in chiral resolution. Under the optimal reaction conditions, the immobilized BCL showed a very good performance and significantly shortened the reaction equilibrium time from 30 h of the free lipase to 2 h with a conversion rate of 50.0% and ees at 99.2%. The immobilized lipase also exhibited good operational stability; after being used for 10 cycles, it still retained over 80% of its original activity. Moreover, it could keep more than 80% activity after storage for 20 days at room temperature in a dry environment. In addition, to learn the potential mechanism, the morphology of the particles and the immobilized lipase were both characterized with a scanning electron microscope and confocal laser scanning microscopy. It was found that the enlarged spherical surface of the particle in low pH values probably led to high immobilized efficiency, resulting in the improvement of enantioselectivity activity in chiral resolution.

Algunos complejos de carboxilatos de uranio (IV y 1-pirazolilborato

Directory of Open Access Journals (Sweden)

Omar Velasquez

2009-07-01

Full Text Available En este trabajo se presenta la síntesis y caracterización, mediante espectroscopia de infrarojo y H'—NMR de complejos de acetato de uranio, dietil carbamatos y dietilditiocarbamatos y 1—pirazolil—borato.

Control of Ge1-x-ySixSny layer lattice constant for energy band alignment in Ge1-xSnx/Ge1-x-ySixSny heterostructures

Science.gov (United States)

Fukuda, Masahiro; Watanabe, Kazuhiro; Sakashita, Mitsuo; Kurosawa, Masashi; Nakatsuka, Osamu; Zaima, Shigeaki

2017-10-01

The energy band alignment of Ge1-xSnx/Ge1-x-ySixSny heterostructures was investigated, and control of the valence band offset at the Ge1-xSnx/Ge1-x-ySixSny heterointerface was achieved by controlling the Si and Sn contents in the Ge1-x-ySixSny layer. The valence band offset in the Ge0.902Sn0.098/Ge0.41Si0.50Sn0.09 heterostructure was evaluated to be as high as 330 meV, and its conduction band offset was estimated to be 150 meV by considering the energy bandgap calculated from the theoretical prediction. In addition, the formation of the strain-relaxed Ge1-x-ySixSny layer was examined and the crystalline structure was characterized. The epitaxial growth of a strain-relaxed Ge0.64Si0.21Sn0.15 layer with the degree of strain relaxation of 55% was examined using a virtual Ge substrate. Moreover, enhancement of the strain relaxation was demonstrated by post-deposition annealing, where a degree of strain relaxation of 70% was achieved after annealing at 400 °C. These results indicate the possibility for enhancing the indirect-direct crossover with a strained and high-Sn-content Ge1-xSnx layer on a strain-relaxed Ge1-x-ySixSny layer, realizing preferable carrier confinement by type-I energy band alignment with high conduction and valence band offsets.

Crecimiento y desarrollo de niños y jóvenes con diabetes mellitus tipo 1

Directory of Open Access Journals (Sweden)

Enrique Rotemberg Wilf

Full Text Available Resumen La diabetes mellitus es un síndrome metabólico que se caracteriza por hiperglucemia con alteración en el metabolismo de los carbohidratos, proteínas y grasas, causada por deficiencias en la producción o en la utilización de la insulina. Es la enfermedad endocrinometabólica más frecuente de la infancia y adolescencia. La diabetes tipo 1 es una condición crónica debido a la destrucción de las células beta de los islotes de Langerhans del páncreas por enfermedad autoinmune o sin causa conocida. El crecimiento y desarrollo general y cráneo facial del individuo van a estar influenciados por distintos factores que actúan interrelacionados. Los profesionales de la salud deben controlar la evolución del niño con diabetes 1 especialmente durante la pubertad. Es probable encontrar diferencias de crecimiento y desarrollo entre jóvenes con eficaz o con pobre control glucémico, en especial si la enfermedad es de inicio prepuberal y si es o no diagnosticada en forma precoz. La diabetes mellitus tipo 1 puede afectar la salud buco-dental de niños y adolescentes, con posibles consecuencias en la vida adulta

Waste Isolation Pilot Plant Annual Site Environmental Report for 2016

Energy Technology Data Exchange (ETDEWEB)

Ward, Anderson [Carlsbad Field Office (CBFO), NM (United States); Basabilvazo, George T. [Carlsbad Field Office (CBFO), NM (United States)

2017-09-01

The purpose of the Waste Isolation Pilot Plant (WIPP) Annual Site Environmental Report for 2016 (ASER) is to provide the information required by U.S. Department of Energy (DOE) Order 231.1B, Environment, Safety, and Health Reporting. The DOE Carlsbad Field Office (CBFO) and the management and operating contractor (MOC) maintain and preserve the environmental resources at the WIPP facility. DOE Order 231.1B; DOE Order 436.1, Departmental Sustainability; and DOE Order 458.1, Radiation Protection of the Public and the Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and workers, and preservation of the environment. This report was prepared in accordance with DOE Order 231.1B, which requires DOE facilities to submit an ASER to the DOE Headquarters Chief Health, Safety, and Security Officer.

Modeling and optimization of poly(3hydroxybutyrate-co-3hydroxyvalerate) production from cane molasses by Azohydromonas lata MTCC 2311 in a stirred-tank reactor: effect of agitation and aeration regimes.

Science.gov (United States)

Zafar, Mohd; Kumar, Shashi; Kumar, Surendra; Dhiman, Amit K

2012-07-01

The effects of agitation and aeration rates on copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] production by Azohydromonas lata MTCC 2311 using cane molasses supplemented with propionic acid in a bioreactor were investigated. The experiments were conducted in a three-level factorial design by varying the impeller (150-500 rev min(-1)) and aeration (0.5-1.5 vvm) rates. Further, the data were fitted to mathematical models [quadratic polynomial equation and artificial neural network (ANN)] and process variables were optimized by genetic algorithm-coupled models. ANN and hybrid ANN-GA were found superior for modeling and optimization of process variables, respectively. The maximum copolymer concentration of 7.45 g l(-1) with 21.50 mol% of 3HV was predicted at process variables: agitation speed, 287 rev min(-1); and aeration rate, 0.85 vvm, which upon validation gave 7.20 g l(-1) of P(3HB-co-3HV) with 21 mol% of 3HV with the prediction error (%) of 3.38 and 2.32, respectively. Agitation speed established a relative high importance of 72.19% than of aeration rate (27.80%) for copolymer accumulation. The volumetric gas-liquid mass transfer coefficient (k (L) a) was strongly affected by agitation and aeration rates. The highest P(3HB-co-3HV) productivity of 0.163 g l(-1) h(-1) was achieved at 0.17 s(-1) of k (L) a value. During the early phase of copolymer production process, 3HB monomers were accumulated, which were shifted to 3HV units (9-21%) during the cultivation period of 24-42 h. The enhancement of 7.5 and 34% were reported for P(3HB-co-3HV) production and 3HV content, respectively, by hybrid ANN-GA paradigm, which revealed the significant utilization of cane molasses for improved copolymer production.

Interband Stark effects in InxGa1-xAs/InyAl1-yAs coupled step quantum wells

International Nuclear Information System (INIS)

Kim, J.H.; Kim, T.W.; Yoo, K.H.

2005-01-01

The effects of an electric field on the interband transitions in In x Ga 1-x As/In y Al 1-y As coupled step quantum wells have been investigated both experimentally and theoretically. A In x Ga 1-x As/In y Al 1-y As coupled step quantum well sample consisted of the two sets of a 50 Aa In 0.53 Ga 0.47 As shallow quantum well and a 50 Aa In 0.65 Ga 0.35 As deep step quantum well bounded by two thick In 0.52 Al 0.48 As barriers separated by a 30 Aa In 0.52 Al 0.48 As embedded potential barrier. The Stark shift of the interband transition energy in the In x Ga 1-x As/In y Al 1-y As coupled step quantum well is larger than that of the single quantum well, and the oscillator strength in the In x Ga 1-x As/In y Al 1-y As coupled step quantum well is larger than that in a coupled rectangular quantum well. These results indicate that In x Ga 1-x As/In y Al 1-y As coupled step quantum wells hold promise for potential applications in optoelectron devices, such as tunable lasers

Effects of artificial holes in very large single-grain Y_1_._5Ba_2Cu_3O_7_-_y bulk superconductors

International Nuclear Information System (INIS)

Park, S. D.; Jun, B. H.; Kim, C. J.; Park, H. W.

2017-01-01

The effects of artificial holes on the trapped magnetic fields and magnetic levitation forces of very large single-grain Y_1_._5Ba_2Cu_3O_7_-_y (Y1.5) bulk superconductors were studied. Artificial holes were made for Y1.5 powder compacts by die pressing using cylindrical dies with a diameter of 30 mm or 40 m, or rectangular dies with a side length of 50 mm. The single grain Y1.5 bulk superconductors (25 mm, 33 mm in diameter and 42 mm in side length) with artificial holes were fabricated using a top-seeded melt growth (TSMG) process for the die-pressed Y1.5 powder compacts. The magnetic levitation forces at 77 K of the 25 mm single grain Y1.5 samples with one (diameters of 4.2 mm) or six artificial holes (diameters of 2.5 mm) were 10-17% higher than that of the Y1.5 sample without artificial holes. The trapped magnetic fields at 77 K of the Y1.5 samples with artificial holes were also 9.6-18% higher than that of the Y1.5 sample without artificial holes. The 33 mm and 42 mm single grain Y1.5 samples with artificial holes (2.5 mm and 4.2 mm in diameter) also showed trapped magnetic fields 10-13% higher than that of the Y1.5 samples without artificial holes in spite of the reduced superconducting volume fraction due to the presence of artificial holes. The property enhancement in the large single grain Y1.5 bulk superconductors appears to be attributed to the formation of the pore-free regions near the artificial holes and the homogeneous oxygen distribution in the large Y123 grains

Phase conversion from hexagonal CuS(y)Se(1-y) to cubic Cu(2-x)S(y)Se(1-y): composition variation, morphology evolution, optical tuning, and solar cell applications.

Science.gov (United States)

Xu, Jun; Yang, Xia; Yang, Qingdan; Zhang, Wenjun; Lee, Chun-Sing

2014-09-24

In this work, we report a simple and low-temperature approach for the controllable synthesis of ternary Cu-S-Se alloys featuring tunable crystal structures, compositions, morphologies, and optical properties. Hexagonal CuS(y)Se(1-y) nanoplates and face centered cubic (fcc) Cu(2-x)S(y)Se(1-y) single-crystal-like stacked nanoplate assemblies are synthesized, and their phase conversion mechanism is well investigated. It is found that both copper content and chalcogen composition (S/Se atomic ratio) of the Cu-S-Se alloys are tunable during the phase conversion process. Formation of the unique single-crystal-like stacked nanoplate assemblies is resulted from oriented stacking coupled with the Ostwald ripening effect. Remarkably, optical tuning for continuous red shifts of both the band-gap absorption and the near-infrared localized surface plasmon resonance are achieved. Furthermore, the novel Cu-S-Se alloys are utilized for the first time as highly efficient counter electrodes (CEs) in quantum dot sensitized solar cells (QDSSCs), showing outstanding electrocatalytic activity for polysulfide electrolyte regeneration and yielding a 135% enhancement in power conversion efficiency (PCE) as compared to the noble metal Pt counter electrode.

Grain dust originating from organic and conventional farming as a potential source of biological agents causing respiratory diseases in farmers.

Science.gov (United States)

Zukiewicz-Sobczak, Wioletta A; Cholewa, Grażyna; Krasowska, Ewelina; Chmielewska-Badora, Jolanta; Zwoliński, Jacek; Sobczak, Paweł

2013-12-01

Agricultural producers are exposed to a number of different health risks associated with their work environment. The objective of the study was to assess the degree of colonization by fungi in terms of quantity and in terms of variety of species the samples taken from the settled dust from combine threshing of rye cultivation from organic and conventional farms in the Province of Lublin. This paper is a preliminary quantitative assessment of the species of fungi colonizing the samples of settled dust collected during combine threshing from organic and conventional farms in the Province of Lublin. One of the stages of the project was the classification of biosafety BSL (biosafety level) of selected isolates and API ZYM tests to evaluate the potential ability of isolates to cause adverse health effects. To determine the concentration and composition of fungi in collected samples plate dilution method was used with two media: Malt Agar and Potato Dextrose Agar. MOST COMMONLY ISOLATED FUNGI IN SETTLED DUST SAMPLES COLLECTED DURING COMBINE THRESHING FROM ORGANIC FARMS, ON PDA MEDIUM WERE: Alternaria alternata and Aureobasidium pullulans. Cultures on MA medium were dominated by Alternaria alternata, Mycelia sterilia and Fusarium poae. In samples of dust from conventional crops, the predominant species was Alternaria alternata on PDA medium and on MA medium. The obtained results show a potential risk of people involved in agricultural work.

Study on the effects of near-future ocean acidification on marine yeasts: a microcosm approach

Science.gov (United States)

Krause, Evamaria; Wichels, Antje; Erler, René; Gerdts, Gunnar

2013-12-01

Marine yeasts play an important role in biodegradation and nutrient cycling and are often associated with marine flora and fauna. They show maximum growth at pH levels lower than present-day seawater pH. Thus, contrary to many other marine organisms, they may actually profit from ocean acidification. Hence, we conducted a microcosm study, incubating natural seawater from the North Sea at present-day pH (8.10) and two near-future pH levels (7.81 and 7.67). Yeasts were isolated from the initial seawater sample and after 2 and 4 weeks of incubation. Isolates were classified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and representative isolates were identified by partial sequencing of the large subunit rRNA gene. From the initial seawater sample, we predominantly isolated a yeast-like filamentous fungus related to Aureobasidium pullulans, Cryptococcus sp., Candida sake, and various cold-adapted yeasts. After incubation, we found more different yeast species at near-future pH levels than at present-day pH. Yeasts reacting to low pH were related to Leucosporidium scottii, Rhodotorula mucilaginosa, Cryptococcus sp., and Debaryomyces hansenii. Our results suggest that these yeasts will benefit from seawater pH reductions and give a first indication that the importance of yeasts will increase in a more acidic ocean.

Biotechnological Applications of Dimorphic Yeasts

Science.gov (United States)

Doiphode, N.; Joshi, C.; Ghormade, V.; Deshpande, M. V.

The dimorphic yeasts have the equilibrium between spherical growth (budding) and polarized (hyphal or pseudohyphal tip elongation) which can be triggered by change in the environmental conditions. The reversible growth phenomenon has made dimorphic yeasts as an useful model to understand fungal evolution and fungal differentiation, in general. In nature dimorphism is clearly evident in plant and animal fungal pathogens, which survive and most importantly proliferate in the respective hosts. However, number of organisms with no known pathogenic behaviour also show such a transition, which can be exploited for the technological applications due to their different biochemical make up under different morphologies. For instance, chitin and chitosan production using dimorphic Saccharomyces, Mucor, Rhizopus and Benjaminiella, oil degradation and biotransformation with yeast-form of Yarrowia species, bioremediation of organic pollutants, exopolysac-charide production by yeast-phase of Aureobasidium pullulans, to name a few. Myrothecium verrucaria can be used for seed dressing in its yeast form and it produces a mycolytic enzyme complex in its hyphal-form for the biocontrol of fungal pathogens, while Beauveria bassiana and other entomopathogens kill the insect pest by producing yeast- like cells in the insect body. The form-specific expression of protease, chitinase, lipase, ornithine decarboxylase, glutamate dehydrogenases, etc. make Benjaminiella poitrasii, Basidiobolus sp., and Mucor rouxii strains important in bioremediation, nanobiotechnology, fungal evolution and other areas.

Bloque 1. Temas 1 y 2. Contenidos, evolución epistemológica y fuentes de la Geografía Rural

OpenAIRE

Segrelles, José Antonio

2011-01-01

Los temas 1 y 2 se incluyen en el bloque 1 y se dedican al análisis de la evolución epistemológica de la geografía rural y a las fuentes para el estudio de esta disciplina, respetivamente. Dentro de la evolución epistemológica se presta especial atención al concepto de geografía rural, a las diversas interpretaciones que éste ha tenido, a la diferente forma en que la geografía rural ha sido estudiada por los diferentes enfoques que ha jalonado su desarrollo científico en el marco de la evoluc...

Iniciativa personal y emprendedora del alumnado de Primaria y 1º ciclo Secundaria: Aspectos personales, familiares y escolares

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Rosalia Romero Tena

2016-10-01

Full Text Available Objeto: Conocer qué aspectos familiares, personales, del centro, del aula y del tipo de enseñanza fomentan la iniciativa personal y emprendedora. Describir el estado actual de la cuestión. Diseño/metodología: Elaborar y validar el instrumento de evaluación para conocer la iniciativa personal y emprendedora del alumnado de Primaria y 1º ciclo de Secundaria. Administrar a centros andaluces el cuestionario de corte cuantitativo -ítems tipo Likert y dicotómicos- de cuatro dimensiones: entorno cercano, centro, actividades didácticas, medios didácticos usados, clima escolar e iniciativa personal. Aportaciones y resultados: El alumno adquiere sus primeras experiencias sobre lo que significa ser una persona emprendedora de la familia y del entorno cercano. El tipo de enseñanza que se imparte el centro así como la utilización de los recursos y medios disponibles marcan el desarrollo de su actitud como persona emprendedora. Las relaciones con los compañeros y con las personas implicadas en sus vidas influyen en tener mayor o menor iniciativa ante las situaciones. Los resultados de la dimensión Iniciativa Personal  (liderazgo, creatividad, logros y percepción del control señalan que a los estudiantes de estas edades les cuesta exponer y defender sus ideas, les agrada que les enseñen de forma diferente y no tienen interés en hacer propuestas. Limitaciones: Económicas, temporales, espaciales y del modelo conceptual. Implicaciones prácticas: Los hallazgos ofrecen pautas a considerar en el diseño de programas educativos que trabajen tanto en la "sensibilización" como en la "preparación" para fomentar la actitud de iniciativa personal y emprendedora. Implicaciones sociales: Concienciar a la comunidad educativa del centro de la importancia de implicar a todos los miembros en el fomento la cultura emprendedora. Valor añadido: Cuando existe una cultura emprendedora en el centro todas las acciones están dirigidas a desarrollar esas

The diversity, extracellular enzymatic activities and photoprotective compounds of yeasts isolated in Antarctica

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Aline B. M Vaz

2011-09-01

Full Text Available The diversity of yeasts collected from different sites in Antarctica (Admiralty Bay, King George Island and Port Foster Bay and Deception Island and their ability to produce extracellular enzymes and mycosporines were studied. Samples were collected during the austral summer season, between November 2006 and January 2007, from the rhizosphere of Deschampsia antarctica, ornithogenic (penguin guano soil, soil, marine and lake sediments, marine water and freshwater from lakes. A total of 89 isolates belonging to the following genera were recovered: Bensingtonia, Candida, Cryptococcus, Debaryomyces, Dioszegia, Exophiala, Filobasidium, Issatchenkia (Pichia, Kodamaea, Leucosporidium, Leucosporidiella, Metschnikowia, Nadsonia, Pichia, Rhodotorula, and Sporidiobolus, and the yeast-like fungi Aureobasidium, Leuconeurospora and Microglossum. Cryptococcus victoriae was the most frequently identified species. Several species isolated in our study have been previously reported to be Antarctic psychophilic yeasts, including Cr. antarcticus, Cr. victoriae, Dioszegia hungarica and Leucosporidium scottii. The cosmopolitan yeast species A. pullulans, C. zeylanoides, D. hansenii, I. orientalis, K. ohmeri, P. guilliermondii, Rh. mucilaginosa, and S. salmonicolor were also isolated. Five possible new species were identified. Sixty percent of the yeasts had at least one detectable extracellular enzymatic activity. Cryptococcus antarcticus, D. aurantiaca, D. crocea, D. hungarica, Dioszegia sp., E. xenobiotica, Rh. glaciales, Rh. laryngis, Microglossum sp. 1 and Microglossum sp. 2 produced mycosporines. Of the yeast isolates, 41.7% produced pigments and/or mycosporines and could be considered adapted to survive in Antarctica. Most of the yeasts had extracellular enzymatic activities at 4ºC and 20ºC, indicating that they could be metabolically active in the sampled substrates.

Los virus Influenza y la nueva pandemia A/H1N1

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Miguel Talledo

2011-07-01

Full Text Available Los virus Influenza pertenecen a la familia Orthomyxoviridae, virus con genoma RNA de sentido negativo segmentado. Los virus influenza tipo A infectan a humanos y otros organismos, y son los agentes causantes de influenza en humanos. Resaltan entre sus principales proteínas la Hemaglutinina y la Neuraminidasa, que son utilizadas en la clasificación de los miembros de este grupo. Estos virus mutan continuamente, exhibiendo patrones muy estudiados, como el cambio y la deriva antigénica, siendo uno de los principales eventos de recombinación el reordenamiento. Todos los subtipos se encuentran en aves acuáticas silvestres, aunque se han encontrado otros hospederos, como equinos, visones, ballenas, focas, cerdos, gallinas y pavos, entre otros. Tanto las aves salvajes, las aves domésticas y el cerdo juegan un rol fundamental en la adaptación progresiva del virus al hospedero humano. Aunque los subtipos H2N2 y H3N2 han sido muy comunes, el subtipo H1N1 ha reemergido con mutaciones que le han permitido alcanzar el estado de pandemia en 2009. Este nuevo virus surge de un virus generado por triple reordenamiento con el virus humano, porcino norteamericano y aviar, conteniendo a su vez segmentos génicos de virus influenza porcina euroasiática. Esto ha hecho que el virus presente una enfermedad humana moderada y solamente severa y hasta letal en casos de individuos con condiciones médicas previas. A nivel mundial ha causado más de 134,510 casos y en el Perú alcanza cerca de 3,700 casos. El estado actual indica que la pandemia está por llegar a su pico máximo en el Perú, debido a la alta morbilidad del virus coincidente con la estación más fría del año. Es importante contener al máximo la dispersión del virus, ya que cuanto mayor sea el número de personas que infecte, el mismo estará sometido a un mayor número de eventos de recombinación genética por reordenamiento con virus influenza humanos previos y esto puede condicionar a la

Core-Shell Zn x Cd1- x Se/Zn y Cd1- y Se Quantum Dots for Nonvolatile Memory and Electroluminescent Device Applications

Science.gov (United States)

Al-Amoody, Fuad; Suarez, Ernesto; Rodriguez, Angel; Heller, E.; Huang, Wenli; Jain, F.

2011-08-01

This paper presents a floating quantum dot (QD) gate nonvolatile memory device using high-energy-gap Zn y Cd1- y Se-cladded Zn x Cd1- x Se quantum dots ( y > x) with tunneling layers comprising nearly lattice-matched semiconductors (e.g., ZnS/ZnMgS) on Si channels. Also presented is the fabrication of an electroluminescent (EL) device with embedded cladded ZnCdSe quantum dots. These ZnCdSe quantum dots were embedded between indium tin oxide (ITO) on glass and a top Schottky metal electrode deposited on a thin CsF barrier. These QDs, which were nucleated in a photo-assisted microwave plasma (PMP) metalorganic chemical vapor deposition (MOCVD) reactor, were grown between the source and drain regions on a p-type silicon substrate of the nonvolatile memory device. The composition of QD cladding, which relates to the value of y in Zn y Cd1- y Se, was engineered by the intensity of ultraviolet light, which controlled the incorporation of zinc in ZnCdSe. The QD quality is comparable to those deposited by other methods. Characteristics and modeling of the II-VI quantum dots as well as two diverse types of devices are presented in this paper.

ESTUDIO CONFORMACIONAL EN ALGUNAS 1,3-OXAZINAS Y 1,3-BENZOXAZINAS EMPLEANDO METODOS TEORICOS.

OpenAIRE

HURTADO OCAMPO, SANDRA MARCELA; HURTADO OCAMPO, SANDRA MARCELA

2007-01-01

En la década del cincuenta, resultados experimentales entregados por Urbanski y colaboradores [1] pusieron en evidencia propiedades antituberculósicas y antitumorales en compuestos del tipo 5-nitro-R-N-1 ,3- oxazínicos. Como resultado de un proceso relati 187p.

Structural evolution and dielectric properties of (Ba{sub 1−x}Nd{sub x})(Ti{sub 1−y}Fe{sub y})O{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Han, D.-D. [Research Center for Materials Science and Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); College of Chemistry, Northeast Normal University, Changchun 130024 (China); Lu, D.-Y., E-mail: cninjp11232000@yahoo.com [Research Center for Materials Science and Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China); Sun, X.-Y. [Research Center for Materials Science and Engineering, Jilin Institute of Chemical Technology, Jilin 132022 (China)

2013-11-05

Highlights: •Structural evolution and dielectric properties of (Ba{sub 1−x}Nd{sub x})(Ti{sub 1−y}Fe{sub y})O{sub 3} were studied. •A cubic ceramic with x = y = 0.05 exhibits a high-k Y5V behavior (ε{sub RT}{sup ′} = 6790). •The T{sub m} in BNTF with x = 0.05 decreased linearly at a rate of −5 °C/mol% Fe ions. •Evolution in the 840 cm{sup −1} Raman band gives evidence for Nd{sup 3+}–Fe{sup 3+} complex formation. •Defect chemistry associated with structure evolution is discussed. -- Abstract: The influence of donor and acceptor co-doping on structure and dielectric properties of (Ba{sub 1−x}Nd{sub x})(Ti{sub 1−y}Fe{sub y})O{sub 3} (BNTF) (x = 0.05, y = 0.01–0.07; and x = 0–0.08, y = 0.05) ceramics was investigated with X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), Raman spectroscopy, and dielectric measurements. When x < y, two types of Nd{sup 3+}–Fe{sup 3+} and Fe{sup 3+}–V{sub O}–Fe{sup 3+} defect complexes formed and could not coexist, leading to the mixed phases of cubic and hexagonal. A single-phase ceramic with a cubic or tetragonal structure formed for x ⩾ y and the dielectric-peak temperature (T{sub m}) in BNTF with x = 0.05 decreased linearly with increasing y at a rate of −5 °C/mol% Fe ions. A high-k Y5V behavior can be realized at x = y = 0.05 (i.e., C-N5F5). The same concentrations of Nd{sup 3+} and Fe{sup 3+} formed Nd{sup 3+}–Fe{sup 3+} complexes, which could effectively suppress the dielectric loss and silence the 840 cm{sup −1} band called “Raman charge effect” associated with Nd{sup 3+} donors. C-N5F5 exhibited a cubic structure, medium-sized grains (3.3 μm), low dielectric loss (<0.06), and high-k Y5V behavior (ε{sub RT}{sup ′} = 6790). Defect chemistry associated with structure evolution is discussed.

Conocimientos y prácticas sobre la prevención y el control de la influenza AH1N1 en una comunidad de Floridablanca, Santander

OpenAIRE

María Paula Sarmiento; Oliverio Suárez; Jesús Antonio Sanabria; Cristhian Eduardo Pérez; Laura del Pilar Cadena; María Eugenia Niño

2011-01-01

Introducción. La influenza AH1N1 generó una pandemia durante el año 2009, para la cual los gobiernos de todo el mundo desarrollaron medidas de mitigación y control de la propagación. En el departamento de Santander se pusieron en práctica planes de prevención orientados a la comunidad. Objetivo. Evaluar los conocimientos y prácticas de la población sobre la prevención y control de la pandemia de influenza AH1N1. Materiales y métodos. Se trató de un estudio transversal con muestreo no pr...

Evolution of Yeast Consortia during the Fermentation of Kalamata Natural Black Olives upon Two Initial Acidification Treatments

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Stamatoula Bonatsou

2018-01-01

Full Text Available The objective of this study was to elucidate the yeast consortia structure and dynamics during Greek-style processing of Kalamata natural black olives in different brine solutions. Olives were subjected to spontaneous fermentation in 7% (w/v NaCl brine solution (control treatment or brine acidified with (a 0.5% (v/v vinegar, and (b 0.1% (v/v lactic acid at the onset of fermentation. Changes in microbial counts, pH, acidity, organic acids, sugars, and alcohols were analyzed for a period of 187 days. Yeast consortia diversity was evaluated at days 4, 34, 90, 140, and 187 of fermentation. A total of 260 isolates were characterized at sub-species level by rep-PCR genomic fingerprinting with the oligo-nucleotide primer (GTG5. The characterization of yeast isolates at species level was performed by sequencing of the D1/D2 domain of 26S rRNA gene. Results showed that yeasts dominated the process presenting a relatively broad range of biodiversity composed of 11 genera and 21 species. No lactic acid bacteria (LAB or Enterobacteriaceae could be enumerated after 20 and 10 days of fermentation, respectively. The dominant yeast species at the beginning were Aureobasidium pullulans for control and vinegar acidification treatments, and Candida naeodendra for lactic acid treatment. Between 34 and 140 days the dominant species were Candida boidinii, Candida molendinolei and Saccharomyces cerevisiae. In the end of fermentation the dominant species in all processes were C. boidinii and C. molendinolei, followed by Pichia manshurica and S. cerevisiae in lactic acid acidification treatment, P. manshurica in vinegar acidification treatment, and Pichia membranifaciens in control fermentation.

Possible involvement of neuropeptide Y Y1 receptors in antidepressant like effect of agmatine in rats.

Science.gov (United States)

Kotagale, Nandkishor R; Paliwal, Nikhilesh P; Aglawe, Manish M; Umekar, Milind J; Taksande, Brijesh G

2013-09-01

Agmatine and neuropeptide Y (NPY) are widely distributed in central nervous system and critically involved in modulation of depressive behavior in experimental animals. However their mutual interaction, if any, in regulation of depression remain largely unexplored. In the present study we explored the possible interaction between agmatine and neuropeptide Y in regulation of depression like behavior in forced swim test. We found that acute intracerebroventricular (i.c.v.) administration of agmatine (20-40μg/rat), NPY (5 and 10μg/rat) and NPY Y1 receptor agonist, [Leu(31), Pro(34)]-NPY (0.4 and 0.8ng/rat) dose dependently decreased immobility time in forced swim test indicating their antidepressant like effects. In combination studies, the antidepressant like effect of agmatine (10μg/rat) was significantly potentiated by NPY (1 and 5μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2 and 0.4ng/rat, icv) pretreatment. Conversely, pretreatment of animals with NPY Y1 receptor antagonist, BIBP3226 (0.1ng/rat, i.c.v.) completely blocked the antidepressant like effect of agmatine (20-40μg/rat) and its synergistic effect with NPY (1μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2ng/rat, icv). The results of the present study showed that, agmatine exerts antidepressant like effects via NPYergic system possibly mediated by the NPY Y1 receptor subtypes and suggest that interaction between agmatine and neuropeptide Y may be relevant to generate the therapeutic strategies for the treatment of depression. Copyright © 2013 Elsevier Inc. All rights reserved.

RELACIÓN DE LOS NIVELES DE HBA1C (% Y DE “FRUCTOSAMINA” (mg/dL EN SUJETOS SALUDABLES Y DIABÉTICOS TIPO 1

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M. Guerra

2007-06-01

Full Text Available Es importante determinar y monitorear el mantenimiento del control metabólico en los pacientes diabéticos. Dado que las concentraciones de hemoglobina glicosilada (HbA1c y de proteínas glicadas diferentes a la hemoglobina, conocidas colectivamente como “fructosamina”, son indicadores del aumento sostenido de la glicemia durante un período de tiempo, se decidió estudiar estos parámetros sanguíneos en un grupo de pacientes diabéticos tipo I en Bogotá, y compararlos con un grupo de individuos saludables.El grupo control estuvo conformado por 25 estudiantes saludables de la Pontificia Universidad Javeriana, Bogotá, DC, seleccionados al azar, y el experimental, por 25 pacientes diabéticos tipo I contactados a través de la Asociación Colombiana de Diabetes, con edades comprendidas entre 15 a 25 años. Con los datos obtenidos se realizaron análisis de regresión y análisis de correlación lineal múltiple. Los resultados mostraron correlación alta (r=0,9 entre HbA1c y “fructosamina”. Se encontró diferencias significantes (p<0,05 entre los controles y los pacientes para ambos parámetros. Los valores de HbA1c y de “fructosamina” fueron independientes de la concentración de glucosa sanguínea durante el estudio.

Improved thermal stability and hole mobilities in a strained-Si/strained-Si1-yGe y/strained-Si heterostructure grown on a relaxed Si1-xGe x buffer

International Nuclear Information System (INIS)

Gupta, Saurabh; Lee, Minjoo L.; Isaacson, David M.; Fitzgerald, Eugene A.

2005-01-01

A dual channel heterostructure consisting of strained-Si/strained-Si 1-y Ge y on relaxed Si 1-x Ge x (y > x), provides a platform for fabricating metal-oxide-semiconductor field-effect transistors (MOSFETs) with high hole mobilities (μ eff ) which depend directly on Ge concentration and strain in the strained-Si 1-y Ge y layer. Ge out-diffuses from the strained-Si 1-y Ge y layer into relaxed Si 1-x Ge x during high temperature processing, reducing peak Ge concentration and strain in the strained-Si 1-y Ge y layer and degrades hole μ eff in these dual channel heterostructures. A heterostructure consisting of strained-Si/strained-Si 1-y Ge y /strained-Si, referred to as a trilayer heterostructure, grown on relaxed Si 1-x Ge x has much reduced Ge out-flux from the strained-Si 1-y Ge y layer and retains higher μ eff after thermal processing. Improved hole μ eff over similar dual channel heterostructures is also observed in this heterostructure. This could be a result of preventing the hole wavefunction tunneling into the low μ eff relaxed Si 1-x Ge x layer due to the additional valence band offset provided by the underlying strained-Si layer. A diffusion coefficient has been formulated and implemented in a finite difference scheme for predicting the thermal budget of the strained SiGe heterostructures. It shows that the trilayer heterostructures have superior thermal budgets at higher Ge concentrations. Ring-shaped MOSFETs were fabricated on both platforms and subjected to various processing temperatures in order to compare the extent of μ eff reduction with thermal budget. Hole μ eff enhancements are retained to a much higher extent in a trilayer heterostructure after high temperature processing as compared to a dual channel heterostructure. The improved thermal stability and hole μ eff of a trilayer heterostructure makes it an ideal platform for fabricating high μ eff MOSFETs that can be processed over higher temperatures without significant losses in hole �

Identification of 6H1 as a P2Y purinoceptor: P2Y5.

Science.gov (United States)

Webb, T E; Kaplan, M G; Barnard, E A

1996-02-06

We have determined the identity of the orphan G-protein coupled receptor cDNA, 6H1, present in activated chicken T cells, as a subtype of P2Y purinoceptor. This identification is based on first on the degree of sequence identity shared with recently cloned members of the P2Y receptor family and second on the pharmacological profile. Upon transient expression in COS-7 cells the 6H1 receptor bound the radiolabel [35S]dATP alpha S specifically and with high affinity (Kd, 10 nM). This specific binding could be competitively displaced by a range of ligands active at P2 purinoceptors, with ATP being the most active (K (i)), 116 nM). Such competition studies have established the following rank order of activity: ATP ADP 2-methylthioATP alpha, beta-methylene ATP, UTP, thus confirming 6H1 as a member of the growing family of P2Y purinoceptors. As the fifth receptor of this type to be identified we suggest that it be named P2Y5.

Oxygen transport in La1-xSrxFe1-yMnyO3-δ perovskites

DEFF Research Database (Denmark)

Mikkelsen, L.; Andersen, I.G.K.; Skou, E.M.

2002-01-01

The oxygen transport in La1-xSrxFe1-yMnyO3-delta (LSFM) with 0 less than or equal to x less than or equal to 0.5 and y = 0.2 and 03 has been examined with a thermogravimetric method. As long as x less than or equal to y, the oxygen transport was found to be very slow while the oxygen transport in...

Synthesis and characterization of perovskite-type Sr{sub x}Y{sub 1−x}FeO{sub 3−δ} (0.63≤x<1.0) and Sr{sub 0.75}Y{sub 0.25}Fe{sub 1−y}M{sub y}O{sub 3−δ} (M=Cr, Mn, Ni), (y=0.2, 0.33, 0.5)

Energy Technology Data Exchange (ETDEWEB)

Biendicho, J.J. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); The ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX Oxfordshire (United Kingdom); Shafeie, S. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Frenck, L. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Université Pierre et Marie Curie, 75005 Paris (France); Gavrilova, D. [M.V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Böhme, S. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Technische Universität Chemnitz, Institut für Chemie, Straße der Nationen 62, D-09111 Chemnitz (Germany); Bettanini, A.M. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); Department of Molecular Sciences and Nanosystems, University Ca’ Foscari of Venice, 30123 Venice (Italy); Svedlindh, P. [Department of Engineering Sciences, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden); Hull, S. [The ISIS Facility, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX Oxfordshire (United Kingdom); Zhao, Z. [School of Industrial Engineering and Management, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Istomin, S.Ya., E-mail: istomin@icr.chem.msu.ru [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden); M.V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Grins, J.; Svensson, G. [Department of Materials and Environmental Chemistry, Stockholm University, S-106 91 Stockholm (Sweden)

2013-04-15

Oxygen-deficient ferrates with the cubic perovskite structure Sr{sub x}Y{sub 1−x}FeO{sub 3−δ} were prepared in air (0.71≤x≤0.91) as well as in N{sub 2} (x=0.75 and 0.79) at 1573 K. The oxygen content of the compounds prepared in air increases with increasing strontium content from 3−δ=2.79(2) for x=0.75 to 3−δ=2.83(2) for x=0.91. Refinement of the crystal structure of Sr{sub 0.75}Y{sub 0.25}FeO{sub 2.79} using TOF neutron powder diffraction (NPD) data shows high anisotropic atomic displacement parameter (ADP) for the oxygen atom resulting from a substantial cation and anion disorder. Electron diffraction (ED) and high-resolution electron microscopy (HREM) studies of Sr{sub 0.75}Y{sub 0.25}FeO{sub 2.79} reveal a modulation along 〈1 0 0〉{sub p} with G± ∼0.4〈1 0 0〉{sub p} indicating a local ordering of oxygen vacancies. Magnetic susceptibility measurements at 5–390 K show spin-glass behaviour with dominating antiferromagnetic coupling between the magnetic moments of Fe cations. Among the studied compositions, Sr{sub 0.75}Y{sub 0.25}FeO{sub 2.79} shows the lowest thermal expansion coefficient (TEC) of 10.5 ppm/K in air at 298–673 K. At 773–1173 K TEC increases up to 17.2 ppm/K due to substantial reduction of oxygen content. The latter also results in a dramatic decrease of the electrical conductivity in air above 673 K. Partial substitution of Fe by Cr, Mn and Ni according to the formula Sr{sub 0.75}Y{sub 0.25}Fe{sub 1−y}M{sub y}O{sub 3−δ} (y=0.2, 0.33, 0.5) leads to cubic perovskites for all substituents with y=0.2. Their TECs are higher in comparison with un-doped Sr{sub 0.75}Y{sub 0.25}FeO{sub 2.79}. Only M=Ni has increased electrical conductivity compared to un-doped Sr{sub 0.75}Y{sub 0.25}FeO{sub 2.79}. - Graphical abstract: Oxygen-deficient ferrates with the cubic perovskite structure Sr{sub x}Y{sub 1−x}FeO{sub 3−δ} were prepared both in air (0.71≤x≤0.91) and N{sub 2} (x=0.75 and 0.79) at 1573 K. Refinement of the

Actitudes y comportamientos preventivos durante la pandemia degripe (H1N1 2009 en España

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Fernando Agüero Santagelo

2011-01-01

Full Text Available Fundamentos: En la primavera de 2009 la aparición del nuevo virus de la gripe (H1N1 2009 causó una enorme alarma social. El objetivo de este estudio es describir los conocimientos y las percepciones de riesgo sobre la enfermedad y su vacuna así como las medidas preventivas adoptadas por la población general en España. Métodos: Encuesta telefónica en dos oleadas a una muestra de teléfonos fijos con cuotas por edad, sexo, Comunidades Autonómicas y tamaño de municipio. El cuestionario incluía preguntas sobre percepciones, medidas preventivas y vacunación contra la gripe (H1N1 2009. Se realizó un análisis estadístico descriptivo de las principales variables del estudio y se aplicó la prueba chi-cuadrado para estudiar la relación estadística para datos categóricos. Resultados: Respondieron el cuestionario 1.627 personas. 823 (51,6% eran mujeres; 502 (30,9% tenían entre 18 y 35 años y 580 (35,6% entre 35 y 55. 729 (49,1% eran trabajadores manuales y 857 (52,7% vivían en municipios de más de 50.000 habitantes. Únicamente un 15,7% de los que respondieron se sentía a riesgo de contraer la enfermedad, percepción que disminuyó al 3,9% en la segunda oleada, tra el pico epidémico. En conjunto, más del 80% (n=1.353 pensaba que se había generado alarma social, y el 77% adoptó al menos una medida preventiva. Las medidas preventivas más frecuentemente adoptadas fueron cubrirse la boca y la nariz con un pañuelo al toser o estornudar (n=951 ; 58,5% y la higiene de manos (n= 624 ; 38,4%. Conclusión: Las principales medidas adoptadas fueron las recomendadas por las autoridades sanitarias.

Conocimientos y prácticas sobre la nueva influenza A (H1N1) en trabajadores de salud y pacientes ambulatorios, Perú (mayo 2009)

OpenAIRE

Jeannette Ávila; César V. Munayco; Jorge Gomez; Juan Nunura; Jerónimo Canahuiri

2009-01-01

Con el objetivo de determinar el nivel de conocimientos, las actitudes y prácticas de los pacientes y del personal de salud a inicios de la pandemia de la nueva Influenza A H1N1, desarrollamos un estudio descriptivo de corte transversal en establecimientos del Ministerio de Salud del Perú (MINSA) sobre 313 usuarios y 244 trabajadores de 4 ciudades del país. El 38% de los pacientes encuestados asocia la nueva Influenza A (H1N1) con los cerdos o aves, un 17% no reconoce que la transmisión es de...

Enhanced Y1-receptor-mediated vasoconstrictive action of neuropeptide Y (NPY) in superior mesenteric arteries in portal hypertension.

Science.gov (United States)

Wiest, Reiner; Jurzik, Lars; Moleda, Lukas; Froh, Matthias; Schnabl, Bernd; von Hörsten, Stephan; Schölmerich, Juergen; Straub, Rainer H

2006-03-01

Vascular hyporeactivity to catecholamines contributes to arterial vasodilation and hemodynamic dysregulation in portal hypertension. Neuropeptide Y (NPY) is a sympathetic neurotransmitter facilitating adrenergic vasoconstriction via Y1-receptors on the vascular smooth muscle. Therefore, we investigated its role for vascular reactivity in the superior mesenteric artery (SMA) of portal vein ligated (PVL) and sham operated rats. In vitro perfused SMA vascular beds of rats were tested for the cumulative dose-response to NPY dependent on the presence and level of alpha1-adrenergic vascular tone (methoxamine MT: 0.3-10 microM). Moreover, the effect of NPY (50 nM) on vascular responsiveness to alpha1-adrenergic stimulation (MT: 0.3-300 microM) was evaluated. Y1-receptor function was tested by Y1-selective inhibition using BIBP-3226 (1 microM). NPY dose-dependently and endothelium-independently enhanced MT-pre-constriction in SMA. This potentiation was increasingly effective with increasing adrenergic pre-stimulation and being more pronounced in PVL rats as compared to sham rats at high MT concentrations. NPY enhanced vascular contractility only in PVL rats correcting the adrenergic vascular hyporeactivity. Y1-receptor inhibition completely abolished NPY-evoked vasoconstrictive effects. NPY endothelium-independently potentiates adrenergic vasoconstriction via Y1-receptors being more pronounced in portal hypertension improving mesenteric vascular contractility and thereby correcting the splanchnic vascular hyporeactivity. This makes NPY a superior vasoconstrictor counterbalancing arterial vasodilation in portal hypertension.

Identification, expression and phylogenetic analysis of EgG1Y162 from Echinococcus granulosus

Science.gov (United States)

Zhang, Fengbo; Ma, Xiumin; Zhu, Yuejie; Wang, Hongying; Liu, Xianfei; Zhu, Min; Ma, Haimei; Wen, Hao; Fan, Haining; Ding, Jianbing

2014-01-01

Objective: This study was to clone, identify and analyze the characteristics of egG1Y162 gene from Echinococcus granulosus. Methods: Genomic DNA and total RNAs were extracted from four different developmental stages of protoscolex, germinal layer, adult and egg of Echinococcus granulosus, respectively. Fluorescent quantitative PCR was used for analyzing the expression of egG1Y162 gene. Prokaryotic expression plasmid of pET41a-EgG1Y162 was constructed to express recombinant His-EgG1Y162 antigen. Western blot analysis was performed to detect antigenicity of EgG1Y162 antigen. Gene sequence, amino acid alignment and phylogenetic tree of EgG1Y162 were analyzed by BLAST, online Spidey and MEGA4 software, respectively. Results: EgG1Y162 gene was expressed in four developmental stages of Echinococcus granulosus. And, egG1Y162 gene expression was the highest in the adult stage, with the relative value of 19.526, significantly higher than other three stages. Additionally, Western blot analysis revealed that EgG1Y162 recombinant protein had good reaction with serum samples from Echinococcus granulosus infected human and dog. Moreover, EgG1Y162 antigen was phylogenetically closest to EmY162 antigen, with the similarity over 90%. Conclusion: Our study identified EgG1Y162 antigen in Echinococcus granulosus for the first time. EgG1Y162 antigen had a high similarity with EmY162 antigen, with the genetic differences mainly existing in the intron region. And, EgG1Y162 recombinant protein showed good antigenicity. PMID:25337206

Identification, expression and phylogenetic analysis of EgG1Y162 from Echinococcus granulosus.

Science.gov (United States)

Zhang, Fengbo; Ma, Xiumin; Zhu, Yuejie; Wang, Hongying; Liu, Xianfei; Zhu, Min; Ma, Haimei; Wen, Hao; Fan, Haining; Ding, Jianbing

2014-01-01

This study was to clone, identify and analyze the characteristics of egG1Y162 gene from Echinococcus granulosus. Genomic DNA and total RNAs were extracted from four different developmental stages of protoscolex, germinal layer, adult and egg of Echinococcus granulosus, respectively. Fluorescent quantitative PCR was used for analyzing the expression of egG1Y162 gene. Prokaryotic expression plasmid of pET41a-EgG1Y162 was constructed to express recombinant His-EgG1Y162 antigen. Western blot analysis was performed to detect antigenicity of EgG1Y162 antigen. Gene sequence, amino acid alignment and phylogenetic tree of EgG1Y162 were analyzed by BLAST, online Spidey and MEGA4 software, respectively. EgG1Y162 gene was expressed in four developmental stages of Echinococcus granulosus. And, egG1Y162 gene expression was the highest in the adult stage, with the relative value of 19.526, significantly higher than other three stages. Additionally, Western blot analysis revealed that EgG1Y162 recombinant protein had good reaction with serum samples from Echinococcus granulosus infected human and dog. Moreover, EgG1Y162 antigen was phylogenetically closest to EmY162 antigen, with the similarity over 90%. Our study identified EgG1Y162 antigen in Echinococcus granulosus for the first time. EgG1Y162 antigen had a high similarity with EmY162 antigen, with the genetic differences mainly existing in the intron region. And, EgG1Y162 recombinant protein showed good antigenicity.

VARIABILIDAD GENÉTICA DE PARENTALES Y POBLACIONES F1 INTER E INTRAESPECÍFICAS DE Physalis peruviana L. Y P. floridana Rydb.

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JHON ALEXANDER BERDUGO CELY

2015-03-01

Full Text Available RESUMEN La uchuva, Physalis peruviana, es un frutal andino de importancia para la exportación; el principal limitante de su producción en Colombia es el marchitamiento vascular ocasionado por Fusarium oxysporum. En el presente trabajo se propuso generar poblaciones F1 entre parentales contrastantes por su respuesta a éste patógeno y evaluarlas molecularmente como apoyo al conocimiento y uso de los recursos genéticos de la especie. Para ello, cuatro genotipos de P. peruviana y uno de la especie relacionada P. floridana, fueron caracterizados a nivel morfo-agronómico empleando 34 variables cualitativas y 20 cuantitativas, y a nivel molecular con 328 marcadores tipoCOSII y 154 IRGs. Dichos genotipos se utilizaron como parentales para la generación y caracterización molecular de poblaciones F1. Las variables cuantitativas permitieron diferenciar las especies P. floridana y P. peruviana así como genotipos cultivados y silvestres dentro de P. peruviana. Se encontró un 100% de viabilidad en cruces F1 intraespecíficos y un 50% en interespecíficos, siendo viables aquellos donde P. floridana fue receptor de polen. A nivel molecular no se identificaron polimorfismos dentro de P. peruviana pero sí entre P. floridana y P. Peruviana. En una población F1 de 51 individuos generada entre las especies se encontró un total de 127 alelos con un promedio de 3,18 por locus, un PIC de 0,358 y altos valores de heterocigocidad (Ho: 0,737 y He: 0,449. Los análisis de PCA y agrupamiento permitieron discriminar la población F1 en tres grupos, en su mayoría con mayor similitud al parental P. floridana. Lo anterior se reflejó en una distorsión mendeliana del 75% favorecida por la presencia de un 63,75% de alelos maternos. El estudio aporta conocimiento sobre la cruzabilidad en uchuva y la variabilidad genética de genotipos parentales y poblaciones F1.

Magnetic tri-axial orientation in (Y1-xErx)2Ba4Cu7O15-y superconductors

International Nuclear Information System (INIS)

Horii, S.; Okuhira, S.; Yamaki, M.; Haruta, M.; Maeda, T.; Shimoyama, J.

2011-01-01

(Y 1-x Er x ) 2 Ba 4 Cu 7 O 15-y [(Y,Er)247] was synthesized for clarifying a magnetic role of Er ion. The three magnetization axes of (Y,Er)247 were obtained from tri-axial orientation using a modulated rotation magnetic field. Magnetic anisotropy of Er ion is roughly ten times higher than that for Y247 at room temperature. Importance of rare-earth ions was shown for reduction of required magnetic fields in the tri-axial magnetic orientation. We report the tri-axial grain-orientation effects under a modulated rotation magnetic field for (Y 1-x Er x ) 2 Ba 4 Cu 7 O y [(Y, Er)247]. The magnetic easy axis at room temperature was drastically changed around x ∼ 0.1; however, the Er-doping levels for the conversion of magnetic easy axes from the c-axis to the ab-direction and from the a- to b-axes were quite different. Tri-axial single-ion magnetic anisotropy of Er 3+ was roughly 10 times greater than tri-axial magnetic anisotropy generated by both the superconducting CuO 2 plane and the blocking Cu-O chain layer. An appropriate choice of rare-earth (RE) ions in RE-based cuprate superconductors enables the reduction of the required magnetic field for the production of bulks and thick films based on the magnetic orientation technique.

Magnetic ordering and charge transport in electron-doped La1-yCeyMnO3 (0.1 ≤ y ≤ 0.3) films

International Nuclear Information System (INIS)

Prokhorov, V.G.; Kaminsky, G.G.; Flis, V.S.; Hyun, Y.H.; Park, S.Y.; Lee, Y.P.; Svetchnikov, V.L.

2009-01-01

The microstructure and the magnetic and transport properties of as-deposited La 10-y Ce y MnO 3 (0.1≤ y≤ 0.3) films prepared by pulsed laser deposition are investigated in a wide region of temperature and magnetic field. The microstructure analysis reveals that all films have a high c-oriented texture, an orthorhombic crystal lattice, and a negligible quantity of CeO 2 inclusions. The observed strip-domain phase with a periodic spacing of about 3c, the crystal lattice of which is the same as for the basic film phase, exhibits magnetic behavior typical for the Griffiths phase. Regions of the double-period modulated phase are found at room temperature in the y=0.1 film, which is interpreted as Mn 3+ /Mn 2+ ordering with a partial ferromagnetic → antiferromagnetic transition at T N ≤ 80 K. At the same time, the investigation reveals that the magnetic and transport properties of the electron-doped La 1-y Ce y MnO 3 films, driven by cation doping, are similar to those for the hole-doped La/Ca manganites. Therefore, one can conclude that there is no fundamental difference between the mechanisms of spin ordering and charge transport in the hole-doped and electron-doped manganites

CYP1A1, CYP2E1 Y RIESGO A CÁNCER GÁSTRICO EN UNA POBLACIÓN COLOMBIANA DE ALTA INCIDENCIA

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Eduardo Castaño

2009-09-01

Full Text Available El objetivo fue probar la hipótesis de que en casos y controles, de una población colombiana con alta incidencia de cáncer gástrico, muestran diferencias significativas entre las frecuencias de los polimorfismos genéticos CYP1A1-m2 y CYP2E1-c2; y a la vez, probar si hay diferencias entre el hábito del tabaquismo, el consumo de licor y el estrato socioeconómico; así como también sus posibles interacciones. Ochenta y siete pacientes afectados por cáncer gástrico e igual número de controles, del mismo grupo poblacional, genéticamente aislado, pertenecientes a la comunidad “paisa” del departamento de Caldas, fueron genotipíficados por medio de PCR-RFLPs para los polimorfismos CYP1A1-m2 y CYP2E1-c2. Además, se tuvo en cuenta las variables socioeconómicas y el estilo de vida, con respecto al tabaquismo y al consumo de alcohol. Los resultados encontrados sugieren que los portadores del polimorfismo CYP2E1-c2, asociado con mayor actividad metabólica, tienen mayor riesgo a desarrollar cáncer gástrico (OR=3.6, CI95% 1.6-8.1/p=0,002. En contraste, la frecuencia del polimorfismo CYP1A1*2A (MspI, también asociado con mayor actividad enzimática, mostró similar frecuencia entre los dos grupos. El tabaquismo y el estrato socioeconómico bajo, también mostraron diferencias significativas. En conclusión, se evidencia interacción significativa entre gen-ambiente, particularmente entre el tabaquismo y los alelos bioactiavantes CYP2E1- c2 y CYP1A1-m2, que pueden alterar la susceptibilidad a cáncer de estómago en esta región Andina del noroeste de Sur América.

Heat-capacity measurement on (Zr1-ySny)Ox from 325 to 905 K

International Nuclear Information System (INIS)

Tsuji, Toshihide; Amaya, Masaki; Naito, Keiji

1993-01-01

Heat capacities of (Zr 1-y Sn y )O 0.17 and (Zr 1-y Sn y )O 0.28 (y=0-0.07) having α''-ZrO ∼1/6 and α''-ZrO x type crystal structures, respectively, were measured from 325 to 905 K by using an adiabatic scanning calorimeter. Two kinds of heat capacity anomalies were observed for all samples. The anomaly at lower temperatures is attributed to a nonequilibrium phenomenon. Another anomaly at higher temperatures is assigned to an order-disorder rearrangement of oxygen atoms. The transition temperature, transition enthalpy and entropy changes due to the order-disorder transition decreased with increasing tin content, indicating that arrangement of oxygen atoms in the lower temperature phase may be partially disordered by substituting tin for zirconium. The entropy change due to the order-disorder transition for (Zr 1-y Sn y )O 0.17 and (Zr 1-y Sn y )O 0.28 solid solutions is compared with the theoretical value. The solubility limits of (Zr 1-y Sn y )O 0.17 and (Zr 1-y Sn y )O 0.28 were determined from the variation of lattice constants, transition temperature, transition enthalpy and entropy changes against tin content. (orig.)

Competition assays and physiological experiments of soil and phyllosphere yeasts identify Candida subhashii as a novel antagonist of filamentous fungi.

Science.gov (United States)

Hilber-Bodmer, Maja; Schmid, Michael; Ahrens, Christian H; Freimoser, Florian M

2017-01-05

While recent advances in next generation sequencing technologies have enabled researchers to readily identify countless microbial species in soil, rhizosphere, and phyllosphere microbiomes, the biological functions of the majority of these species are unknown. Functional studies are therefore urgently needed in order to characterize the plethora of microorganisms that are being identified and to point out species that may be used for biotechnology or plant protection. Here, we used a dual culture assay and growth analyses to characterise yeasts (40 different isolates) and their antagonistic effect on 16 filamentous fungi; comprising plant pathogens, antagonists, and saprophytes. Overall, this competition screen of 640 pairwise combinations revealed a broad range of outcomes, ranging from small stimulatory effects of some yeasts up to a growth inhibition of more than 80% by individual species. On average, yeasts isolated from soil suppressed filamentous fungi more strongly than phyllosphere yeasts and the antagonistic activity was a species-/isolate-specific property and not dependent on the filamentous fungus a yeast was interacting with. The isolates with the strongest antagonistic activity were Metschnikowia pulcherrima, Hanseniaspora sp., Cyberlindnera sargentensis, Aureobasidium pullulans, Candida subhashii, and Pichia kluyveri. Among these, the soil yeasts (C. sargentensis, A. pullulans, C. subhashii) assimilated and/or oxidized more di-, tri- and tetrasaccharides and organic acids than yeasts from the phyllosphere. Only the two yeasts C. subhashii and M. pulcherrima were able to grow with N-acetyl-glucosamine as carbon source. The competition assays and physiological experiments described here identified known antagonists that have been implicated in the biological control of plant pathogenic fungi in the past, but also little characterised species such as C. subhashii. Overall, soil yeasts were more antagonistic and metabolically versatile than yeasts from

Polymorphic phase transition and morphotropic phase boundary in Ba{sub 1-x}Ca{sub x}Ti{sub 1-y}Zr{sub y}O{sub 3} ceramics

Energy Technology Data Exchange (ETDEWEB)

Abdessalem, M. Ben; Aydi, S.; Aydi, A.; Abdelmoula, N.; Khemakhem, H. [Universite de Sfax, Faculte des Sciences de Sfax (FSS), Laboratoire des Materiaux Multifonctionnels et Applications (LaMMA) LR16ES18, B.P.1171, Sfax (Tunisia); Sassi, Z. [Laboratoire de Genie Electrique et Ferroelectricite (LGEF) de L' INSA de Lyon, Lyon (France)

2017-09-15

This paper deals with Ca and Zr co-doped BaTiO{sub 3} (BCTZ{sub (x,} {sub y)}) (x = 0.1, 0.13, 0.2 and y = 0.05, 0.1, 0.15). These ceramics were prepared using the conventional solid state method. The symmetry, dielectric properties, Raman spectroscopy, ferroelectric behavior and piezoelectric effect were examined. X-ray diffraction (XRD) results display that morphotropic boundary occurs from tetragonal to orthorhombic region of BCZT{sub (x=0.1,} {sub 0.2,} {sub y=0.05,} {sub 0.1)} and polymorphic phase transitions from tetragonal to orthorhombic, orthorhombic to rhombohedral regions of BCZT{sub (x=0.13,} {sub y=0.1)}. The evolution of the Raman spectra was investigated as a function of compositions at room temperature, in correlation with XRD analysis and dielectric measurements. We note that the substitution of Ca in Ba site and Zr ions in Ti site slightly decreased the cubic-tetragonal temperature transition (T{sub C}) and increased the orthorhombic-tetragonal (T{sub 1}) and rhombohedral-orthorhombic (T{sub 2}) temperatures transitions. The ferroelectric properties were examined by a P-E hysteresis loop. The two parameters ΔT{sub 1} and ΔT{sub 2} are defined as ΔT{sub 1} = T{sub C} - T{sub 1} and ΔT{sub 2} = T{sub C} - T{sub 2}, they come close to T{sub C} for x = 0.13, y = 0.1, which reveals that this composition is around the polymorphic phase. The excellent piezoelectric coefficient of d{sub 33} = 288 pC N{sup -1}, the electromechanical coupling factor k{sub p} = 40%, high constant dielectric 9105, coercive field E{sub c} = 0.32 (KV mm{sup -1}) and remanent polarization P{sub r} = 0.1 (μc mm{sup -2}) were obtained for composition x = 0.13, y = 0.1. (orig.)

Nanocrystalline La1-xSrxCo1-yFe yO3 perovskites fabricated by the micro-emulsion route for high frequency response devices fabrications

KAUST Repository

Azhar Khan, Muhammad; Khan, Kamran; Mahmood, Azhar; Murtaza, Gulam; Akhtar, Majid Niaz; Ali, Irshad M.; Shahid, Muhammad; Shakir, Imran; Farooq Warsi, Muhammad

2014-01-01

Nanocrystalline La1-xSrxCo1-yFe yO3 (x=0.00-0.60) perovskites were fabricated by a cheap economic route (i.e. micro-emulsion method) and characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), fourier transform infrared (FTIR

Influence of Rare Earth Elements on Microstructure and Mechanical Properties of Mg{sub 97}Zn{sub 1}Y{sub 1}RE{sub 1} Alloys

Energy Technology Data Exchange (ETDEWEB)

Kim, Jonghyun, E-mail: joindoc@kumamoto-u.ac.jp [Department of Material Science, Magnesium Research Center (MRC), Kumamoto University, Kumamoto, 860-8555 (Japan); Kawamura, Y. [Department of Material Science, Magnesium Research Center (MRC), Kumamoto University, Kumamoto, 860-8555 (Japan)

2013-06-20

Mg{sub 97}Zn{sub 1}Y{sub 1}RE{sub 1} (RE=La, Ce, Nd and Sm, at. %) alloys were prepared by high-frequency induction melting in an Ar atmosphere. Rods were extruded at 623 K and a ram speed of 2.5 mm·s{sup −1} using a circular die with an extrusion ratio of 10. The microstructure and mechanical properties of the extruded alloys were investigated. The Mg{sub 97}Zn{sub 1}Y{sub 1}Nd{sub 1} and Mg{sub 97}Zn{sub 1}Y{sub 1}Sm{sub 1} alloys consisted of only two phases: α-Mg and a Mg-RE intermetallic compound. The Mg{sub 97}Zn{sub 1}Y{sub 1}La{sub 1} and Mg{sub 97}Zn{sub 1}Y{sub 1}Ce{sub 1} alloys consisted of three phases: α-Mg, a Mg-RE intermetallic compound, and a Mg{sub 12}ZnY phase with a long-period stacking ordered (LPSO) phase. Additionally, after extrusion, the three-phase Mg{sub 97}Zn{sub 1}Y{sub 1}RE{sub 1} alloys, i.e., those with an LPSO phase, had a stratified microstructure and exhibited better mechanical properties than those without an LPSO. At room temperature, the yield strength and ultimate tensile strength of the three-phase Mg{sub 97}Zn{sub 1}Y{sub 1}La{sub 1} and Mg{sub 97}Zn{sub 1}Y{sub 1}Ce{sub 1} alloys were 381–384 MPa and 427–429 MPa, respectively, and yield strengths greater than 280 MPa were observed at the elevated temperature of 523 K.

Rhizobacterially induced protection of watermelon against Didymella bryoniae.

Science.gov (United States)

Nga, N T T; Giau, N T; Long, N T; Lübeck, M; Shetty, N P; de Neergaard, E; Thuy, T T T; Kim, P V; Jørgensen, H J L

2010-08-01

To identify rhizobacteria from the Mekong Delta of Vietnam, which can systemically protect watermelon against Didymella bryoniae and elucidate the mechanisms involved in the protection conferred by isolate Pseudomonas aeruginosa 23(1-1). Bacteria were isolated from watermelon roots and their antagonistic ability tested in vitro. Of 190 strains, 68 were able to inhibit D. bryoniae by production of antibiotics. Four strains were able to reduce foliar infection by D. bryoniae when applied to watermelon seeds before sowing. Strain Ps. aeruginosa 23(1-1) was chosen for investigations of the mechanisms involved in protection and ability to control disease under field conditions. In the field, the bacterium was able to significantly reduce disease in two consecutive seasons and increase yield. Furthermore, it colonized watermelon plants endophytically, with higher numbers in plants infected by D. bryoniae than in noninoculated plants. To elucidate the mechanisms involved in protection, the infection biology of the pathogen was studied in bacterially treated and control plants. Pseudomonas aeruginosa 23(1-1) treatment inhibited pathogen penetration and this was associated with hydrogen peroxide accumulation, increased peroxidase activity and occurrence of new peroxidase isoforms, thus indicating that resistance was induced. The endophytic bacterium Ps. aeruginosa 23(1-1) can control D. bryoniae in watermelon by antibiosis and induced resistance under greenhouse and field conditions. These findings suggest that rhizobacteria from native soils in Vietnam can be used to control gummy stem blight of watermelon through various mechanisms including induction of resistance.

Factores de riesgo de hospitalización por gripe (H1N1 2009 y efectividad de intervenciones farmacológicas y no farmacológicas en su prevención. Estudio de casos y controles

Directory of Open Access Journals (Sweden)

Angela Domínguez

2011-01-01

Full Text Available Entre las medidas farmacológicas de posible utilidad para limitar el impacto de las pandemias gripales en la comunidad están los fármacos antivirales (inhibidores de la neuraminidasa y las vacunas antigripales y antineumocócicas, ya que la gripe predispone a la neumonía bacteriana por StrVptoUoUUus pnVumonWTV. Entre las medidas no farmacológicas destacan la higiene de manos y la higiene respiratoria. La falta de conocimiento de la efectividad de dichas medidas en situación de pandemia justifica que en septiembre de 2009, ante la solicitud de proyectos de investigación por parte del Ministerio de Ciencia e Innovación en su Programa de Investigación sobre la gripe (H1N1 2009 en España, el CIBER de Epidemiología y Salud Pública presentara un proyecto multicéntrico de casos y controles emparejados por edad, hospital y fecha de hospitalización para investigar sobre estos aspectos en 37 hospitales de 7 comunidades autónomas. Por cada caso hospitalizado confirmado de gripe pandémica se seleccionaba 1 caso confirmado ambulatorio y 3 controles (2 hospitalarios y 1 ambulatorio. En los casos y en los controles se recogían variables demográficas, condiciones médicas subyacentes, utilización de antivirales, vacunas recibidas y hábitos de higiene. En los casos hospitalizados se recogieron, además, información relativa al tratamiento antiviral y evolución de la enfermedad. Hasta octubre 2010 se habían reclutado un total de 3.750 pacientes y se está realizando la depuración de los datos y la recuperación de variables. La implicación de las Direcciones Generales de Salud Pública ha sido fundamental para la adecuación del proyecto a la evolución de la pandemia.

EFECTO DEL 1-METILCICLOPROPENO (1-MCP SOBRE LA FISIOLOGÍA Y CALIDAD DE FRUTOS DE JACA (Artocarpus heterophyllus Lam.

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M. Mata-Montes de Oca

2007-01-01

Full Text Available Debido a sus características de color y sabor de pulpa, la demanda de fruta de jaca se ha incrementado considerablemente. La mayoría de la producción de Nayarit es exportada a los Estados Unidos de Norteamérica. Sin embargo, debido a su corta vida de anaquel y susceptibilidad al daño por frío la fruta es exportada vía aérea con altos costos de flete. Se reporta que el 1-Metilciclopropeno (1-MCP retarda el proceso de madurez, alarga la vida de anaquel y mantiene la calidad de varios frutales, así que el objetivo de este estudio fue evaluar el efecto del 1-MCP sobre la fisiología y calidad del fruto de jaca almacenado a 20 ºC. Las frutas fueron cosechadas en madurez fisiológica, lavadas y tratadas con 1-MCP a 100 y 300 nl·litro-1 en cámaras selladas por 12 h a 20 ± 1 ºC; 85 ± 5 % de HR manteniendo un testigo sin tratar. Las variables evaluadas fueron: velocidad de respiración y de producción de etileno, sólidos solubles totales, acidez titulable, firmeza de la pulpa y de la fruta entera, color en la pulpa y pérdida de peso. El 1-MCP no afectó la mayoría de las variables de calidad pero retrasó significativamente la velocidad de respiración y la producción de etileno así como el ablandamiento de la pulpa, lo que permitió prolongar la vida de anaquel hasta por ocho y 12 días a 100 y 300 nl·litro-1, respectivamente.

Meta-1 y Mat-1, proteínas metacíclicas en leishmania: clonación, expresión y caracterización inmunológica

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Christof Berberich

2000-02-01

Full Text Available

Los parásitos del género Leishmania causan un amplio espectro clínico de enfermedades en el hombre, referidos colectivamente como leismaniasis. Estos parásitos en la naturaleza se encuentran como dos estadíos. Uno de promastigote, el cual es flagelado, móvil y es la forma encontrada en el intestino del insecto vector y otro de amastigote, el cual es inmóvil, no presenta flagelo y es la forma encontrada dentro de los macrófagos del hospedero mamífero. El promastigote dentro del insecto, sufre una serie de modificaciones que lo transforman desde una forma poco o nada infectivo conocido como promastigote procíclico hasta una forma altamente infectiva o promastigote metacíclico. Este proceso es de vital importancia ya que asegura la producción de parásitos infectivos y con una capacidad aumentada de resistir el ataque del sistema inmune del hospedero vertebrado. Sin embargo, los mecanismos bioquímicos y moleculares de este proceso de diferenciación apenas están siendo dilucidados. Durante la metaciclogénesis se sabe que el parásito modula la expresión de algunas moléculas involucradas en la virulencia. Con el empleo de técnicas que permiten aislar genes expresados diferencialmente se han logrado identificar los genes Meta-1 y Mat-1, que tienen la particularidad de que sus marcos de lectura en el promastigote metacíclico tienen una tasa de transcripción mayor que en promastigotes procíclicos, al menos en Leishmania major. En el presente trabajo se muestra la expresión como proteínas recombinantes de estos dos genes metacíclicos. Además , se presentará una evaluación preliminar de la respuesta inmune humoral y celular frente a las proteínas Meta- 1 y Mat-1 de L. infantum. Para la evaluación humoral se emplearon sueros de pacientes con leishmaniasis cutánea, mucocutánea y visceral, mediante Elisa y Western blot. Títulos bajos de anticuerpos

High-temperature vaporization of thorium-uranium mixed monocarbide (Th1-y, Uy)C

International Nuclear Information System (INIS)

Koyama, Tadafumi; Yamawaki, Michio

1989-01-01

Vaporization thermodynamics of thorium-uranium mixed monocarbide phase (Th 1-y , U y )C was studied by mass spectrometric Knudsen effusion method for the compositions of (Th 0.9 , U 0.1 )C 0.855 , (Th 0.8 , U 0.2 )C 0.973 and (Th 0.6 , U 0.4 )C 0.973 . The partial vapor pressures of Th(g) and U(g) and activities of Th and U of these mixed monocarbides were determined at temperatures ranging from about 2000 to 2200 K. Further, the partial pressures of Th(g) and U(g) and activities of Th and U of the stoichiometric mixed monocarbides (Th 1-y , U y )C 1.00 were evaluated by compensating for the effect of carbon content. The Gibbs energies of formation of stoichiometric (Th 1-y , U y )C 1.00 were also evaluated. (orig.)

Herpesvirus canino 1: agente etiológico y enfermedad

OpenAIRE

Galosi, Cecilia Mónica

2007-01-01

El herpesvirus canino 1 es un alphaherpesvirus del cual se describe un solo serotipo. Este virus fue aislado en varios paises y en Europa es enzoótico en la población canina. Es uno de los principales agentes infecciosos relacionados a lesiones vesiculares en mucosas genitales y es causante de desórdenes reproductivos en caninos tales como reabsorciones fetales, abortos y muertes perinatales. Participa ocasionalmente como causante de la denominada Tos de las Perreras. Epidemiológicamente revi...

Therapeutic potential of combined anti-IL-1β IgY and anti-TNF-α IgY in guinea pigs with allergic rhinitis induced by ovalbumin.

Science.gov (United States)

Guo-Zhu, Hu; Xi-Ling, Zhu; Zhu, Wen; Li-Hua, Wu; Dan, He; Xiao-Mu, Wu; Wen-Yun, Zhou; Wei-Xu, Hu

2015-03-01

We have previously demonstrated that anti-IL-1β immunoglobulin yolk(IgY) inhibits pathological responses in allergic asthma guinea pigs induced by ovalbumin(OVA). This study aims to determine whether the combined blockade of IL-1β and TNF-α can more effectively inhibit allergic inflammation in allergic rhinitis(AR) guinea pigs induced by OVA. Healthy guinea pigs treated with saline were used as the healthy control. The AR guinea pigs induced by OVA were randomly divided into (1) the AR model group containing negative control animals treated with intranasal saline; (2) the 0.1% non-specific IgY treatment group treated with non-specific IgY; (3) the 0.1% anti-TNF-α IgY treatment group treated with 0.1% anti-TNF-α IgY; (4) the 0.1% anti-IL-1β IgY treatment group treated with 0.1% anti-IL-1β IgY; (5) the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group treated with 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY; and (6) the fluticasone propionate treatment group treated with fluticasone propionate. Cytokines were measured using an enzyme-linked immunosorbent assay. The results showed that IL-1β, IL-5, IL-9, IL-13, IL-18, IL-22, IL-33, TNF-α, TGF-β1 and OVA-specific IgE levels in the peripheral blood (PB) and nasal lavage fluid (NLF) significantly decreased at 2h, 4h or 8h in the 0.1% combined anti-IL-1β IgY and anti-TNF-α IgY treatment group compared to the AR model group and the 0.1% non-specific IgY treatment group (P<0.05). The data suggest that blockade of IL-1β and TNF-α by intranasal instillation of combined anti-IL-1β IgY and anti-TNF-α IgY could be a potential alternative strategy for preventing and treating allergic rhinitis. Copyright © 2014. Published by Elsevier B.V.

Fotometría y polarimetría de Lynga 1

Science.gov (United States)

Brusasco, M. A.; Baume, G.; Vázquez, R. A.

Se presentan los resultados de las observaciones fotométricas CCD-UBVRI hasta magnitud aproximadamente V = 18 y polarimétricas hasta V = 13 en la zona del cúmulo abierto Lynga 1. El mismo se halla en una dirección cercana a un remanente de supernova y fue estudiado previamente por Peterson y FitzGerald (1988) mediante fotometría fotoeléctrica. Se ha redeterminado el enrojecimiento, la distancia y la edad de dicho objeto. Se han hallado además los valores de las pendientes de las funciones de luminosidad y de masa comparándoselas con las de otros cúmulos de edades similares.

CAVEOLINA-1 implicaciones fisiológicas y patológicas

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Vanesa Pereira-Prado

Full Text Available Las caveolas son invaginaciones de la membrana plasmática conformada por proteínas denominadas caveolinas. De las tres isoformas de caveolina la más estudiada en el transcurso de los años es caveolina-1 (cav-1, quien juega un papel importante en la señalización celular y su gen CAV-1 corresponde a la familia de genes supresores tumorales. Debido a su rol dependiente del contexto en el cual se encuentra, la función y participación de cav-1 a nivel tumoral es compleja y aún permanece controvertida. Cav-1 interactúa con una serie de moléculas-receptores que regulan inicialmente los pasos de la transformación celular a la malignidad, participando a su vez en el ciclo celular, la angiogénesis, la remodelación de la matriz extracelular, la proliferación celular, entre otras. El estudio de esta molécula adquiere importancia en función a su utilidad como biomarcador asociado a diagnóstico, pronóstico y posible blanco terapéutico en procesos patológicos.

Prácticas sexuales de riesgo y seroprevalencia de infección por VIH-1. HTLV-1, sífilis y hepatitis B en varones drogadictos no endovenosos de Lima.

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Dany MUÑOZ

1997-07-01

Full Text Available Objetivo: Investigar la prevalencia de prácticas sexuales de riesgo para infección por Enfermedades de Transmisión Sexual (ETS y la seroprevalencia de infección por VIH-1, HTLV-1, Hepatitis B y Sífilis en varones Drogadictos no Endovenosos (DNEV de Lima e identificar si ellos podrían ser considerados como grupo de alto riesgo de infección para HIV. Material y métodos: Encuesta anónima por entrevista directa sobre practicas sexuales y antecedentes de ETS, y análisis serológico para anticuerpos contra VIH, HTLV-1, HBc y T pallidum de 298 DNEV voluntarios del Instituto de Salud Mental "Honorio Delgado - Hideyo Noguchi" y de 10 Organizaciones No Gubernamentales ("Comunidades Terapéuticas" de Lima Metropolitana entre Abril y Agosto de 1996. Resultados: Cinco (1.7% muestras fueron positivas para VIH y una resultó indeterminada (ELISA positivo y WB banda gp 160 presente. Siete (2.3% positivas para HTLV- 1, treinta y cuatro (11.4% positivas para Ab Anti-HBc; y una (0.3% fue RPR y FTA-Abs positiva. El promedio de edad fué 28.8 ± 8.1 años. El promedio de tiempo de consumo de drogas más frecuente fue 6.9 ± 6.2 años con el 80% más de un año. Durante la etapa de consumo: el promedio del número de parejas sexuales fue 53.9 ± 243 con una mediana de 15. De los DNEV mantuvieron relaciones sexuales con Parejas Sexuales Estables el 79%, con Encuentros Casuales el 82%, con Meretrices el 62.4% y con Homosexuales el 60%; el uso consistente de condón es bajo con todos los tipos de parejas sexuales y en todos los tipos de relaciones sexuales pero aumenta significativamente en las relaciones sexuales con meretrices. Con el uso de drogas existe un aumento en el número de parejas sexuales y mayor frecuencia de algunas prácticas sexuales de riesgo tal como el coito anal con todos los tipos de parejas sexuales, así mismo un elevado porcentaje (75% mantienen relaciones sexuales estando drogados, y el 32.9% intercambian drogas por sexo. El 43

Receptor subtypes Y1 and Y5 are involved in the renal effects of neuropeptide Y

NARCIS (Netherlands)

Bischoff, A.; Avramidis, P.; Erdbrügger, W.; Münter, K.; Michel, M. C.

1997-01-01

1. Systemic infusion of neuropeptide Y (NPY) reduces renal blood flow and can concomitantly increase diuresis, natriuresis and calciuresis in anaesthetized rats. The present study was designed to investigate whether the apparently contradictory NPY effects on renal blood flow and urine formation and

Magnetic and transport properties of the (Tb{sub 1-} {sub x} Y {sub x} )Mn{sub 2}Si{sub 2} and TbMn{sub 2}(Si{sub 1-} {sub y} Ge {sub y} ){sub 2} systems

Energy Technology Data Exchange (ETDEWEB)

Granovsky, S.A. [Department of Physics, M.V. Lomonosov Moscow State University, Leninskie Gory GSP-2 119992 Moscow (Russian Federation) and TU Dresden, Institut fuer Festkoerperphysik, D-01062, Dresden (Germany)]. E-mail: ser@plms.phys.msu.ru; Gaidukova, I.Yu. [Department of Physics, M.V. Lomonosov Moscow State University, Leninskie Gory GSP-2 119992 Moscow (Russian Federation); Doerr, M. [TU Dresden, Institut fuer Festkoerperphysik, D-01062, Dresden (Germany); Loewenhaupt, M. [TU Dresden, Institut fuer Festkoerperphysik, D-01062, Dresden (Germany); Markosyan, A.S. [Department of Physics, M.V. Lomonosov Moscow State University, Leninskie Gory GSP-2 119992 Moscow (Russian Federation)

2005-04-15

Magnetic and transport characteristics of pseudo-ternary compounds (Tb{sub 1-} {sub x} Y {sub x} )Mn{sub 2}Si{sub 2} and TbMn{sub 2}(Si{sub 1-} {sub y} Ge {sub y} ){sub 2} have been studied. The role of the 4f-3d exchange and Mn-Mn distances in the formation of the magnetic structure of these compounds is discussed.

Structural and electronic properties of zinc blende B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloys via first-principle calculations

Energy Technology Data Exchange (ETDEWEB)

Abdiche, A., E-mail: abdiche_a@yahoo.fr [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Baghdad, R. [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Departement de Technologie, Universite de Mascara, 29000 Mascara (Algeria); Department of Physics and Astronomy, King Saud University, P.O Box 2455, Riyadh 11451 (Saudi Arabia); Riane, R. [Computational Materials Science Laboratory, University Research of Sidi-Bel-Abbes, 22000 Algeria (Algeria); Al-Douri, Y. [Institute of Nono Electronic Engineering, University Malaysia Perlis, 01000 Kangar, Perlis (Malaysia); Guemou, M. [Engineering Physics Laboratory, Tiaret University, 14000 Tiaret (Algeria); Bin-Omran, S. [Department of Physics and Astronomy, King Saud University, P.O Box 2455, Riyadh 11451 (Saudi Arabia)

2012-02-01

The structural and electronic properties of cubic zinc blende BN, BP, AlN and AlP compounds and their B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloys, have been calculated using the non relativistic full-potential linearized-augmented plane wave FP-LAPW method. The exchange-correlation potential is treated with the local density approximation of Perdew and Wang (LDA-PW) as well as the generalized gradient approximation (GGA) of Perdew-Burke and Ernzerhof (GGA-PBE). The calculated structural properties of BN, BP, AlN and AlP compounds are in good agreement with the available experimental and theoretical data. A nonlinear variation of compositions x and y with the lattice constants, bulk modulus, direct and indirect band gaps is found. The calculated bowing of the fundamental band gaps is in good agreement with the available experimental and theoretical value. To our knowledge this is the first quantitative theoretical investigation on B{sub x}Al{sub 1-x}N{sub y}P{sub 1-y} quaternary alloy and still awaits experimental confirmations.

Neuropeptide Y Y1 receptor hippocampal overexpression via viral vectors is associated with modest anxiolytic-like and proconvulsant effects in mice

DEFF Research Database (Denmark)

Olesen, Mikkel V; Christiansen, Søren Hofman Oliveira; Gøtzsche, Casper René

2012-01-01

overexpression was found to be associated with modest anxiolytic-like effect in the open field and elevated plus maze tests, but no effect was seen on depression-like behavior using the tail suspension and forced swim tests. However, the rAAV-Y1 vector modestly aggravated kainate-induced seizures. These data...... in the hippocampus of adult mice and tested the animals in anxiety- and depression-like behavior. Hippocampal Y1 receptors have been suggested to mediate seizure-promoting effect, so the effects of rAAV-induced Y1 receptor overexpression were also tested in kainate-induced seizures. Y1 receptor transgene...

Resolution and evolution of the duck-billed platypus karyotype with an X1Y1X2Y2X3Y3X4Y4X5Y5 male sex chromosome constitution.

Science.gov (United States)

Rens, Willem; Grützner, Frank; O'brien, Patricia C M; Fairclough, Helen; Graves, Jennifer A M; Ferguson-Smith, Malcolm A

2004-11-16

The platypus (2n = 52) has a complex karyotype that has been controversial over the last three decades. The presence of unpaired chromosomes and an unknown sex-determining system especially has defied attempts at conventional analysis. This article reports on the preparation of chromosome-specific probes from flow-sorted chromosomes and their application in the identification and classification of all platypus chromosomes. This work reveals that the male karyotype has 21 pairs of chromosomes and 10 unpaired chromosomes (E1-E10), which are linked by short regions of homology to form a multivalent chain in meiosis. The female karyotype differs in that five of these unpaired elements (E1, E3, E5, E7, and E9) are each present in duplicate, whereas the remaining five unpaired elements (E2, E4, E6, E8, and E10) are absent. This finding indicates that sex is determined by the alternate segregation of the chain of 10 during spermatogenesis so that equal numbers of sperm bear either one of the two groups of five elements, i.e., five X and five Y chromosomes. Chromosome painting reveals that these X and Y chromosomes contain pairing (XY shared) and differential (X- or Y-specific) segments. Y differential regions must contain male-determining genes, and X differential regions should be dosage-compensated in the female. Two models for the evolution of the sex-determining system are presented. The resolution of the longstanding debate over the platypus karyotype is an important step toward the understanding of mechanisms of sex determination, dosage compensation, and karyotype evolution.

The effect of substrate temperature upon the compositions of Mg and Se in Zn{sub 1-x}Mg{sub x}Se{sub y}Te{sub 1-y} layer grown by MOVPE

Energy Technology Data Exchange (ETDEWEB)

Nishio, M.; Ito, R.; Tanaka, K.; Urata, K.; Nakamura, Y.; Tanaka, T. [Department of Electrical and Electronic Engineering, Graduate School of Science and Engineering, Saga University, 1 Honjo, Saga 840-8502 (Japan); Saito, K.; Guo, Q.X. [Synchrotron Light Application Center, Saga University, 1 Honjo, Saga 840-8502 (Japan)

2014-07-15

The growth of Zn{sub 1-x}Mg{sub x}Se{sub y}Te{sub 1-y} layers was performed on (100) ZnTe substrate by metalorganic vapour phase epitaxy using dimethylzinc, bis-methylcyclopentadienyl-magnesium, diethyltelluride and diethylselenide. The effects of substrate temperature upon the compositions of Mg and Se have been investigated. The Mg composition in Zn{sub 1-x}Mg{sub x}Se{sub y}Te{sub 1-y} layer is significantly enhanced at low substrate temperature. Although the Se composition decreases with decreasing the substrate temperature, Zn{sub 1-x}Mg{sub x}Se{sub y}Te{sub 1-y} layer with a relatively high Se composition of 0.3 is obtainable at a low substrate temperature as low as 380 C. For all the layers, a two-mode behaviour with ZnTe- and MgTe-like longitudinal optical phonon modes is confirmed by Raman scattering. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Oxygen potential of Th1-yUyO2+x

International Nuclear Information System (INIS)

Schram, R.P.C.; Cordfunke, E.H.P.

1996-03-01

Oxygen potentials of UO 2 -ThO 2 solid solutions (Th 1-y U y O 2+x ) were retrieved from literature and stored in a database. For each datapoint the oxygen pressure p O 2 the nonstoichiometry x, the temperature T and the uranium concentration y was specified. The data were analyzed using a defect model, which includes electronic disorder, point defects and cluster formation. In addition, the thermochemical representation of Lindemer and Besmann for UO 2+x was extended for the analysis of the Th 1-y U y O 2+x data. The solid solution is regarded as an ideal ternary mixture of UO 2 , ThO 2 and a hypothetical compound U a O b . The thermodynamic properties of this compound U a O b were determined in two oxygen pressure ranges of the database. In both the defect model and thermochemical approach ThO 2 is treated as an inert compound that does not participate in any of the chemical equilibria describing the oxygen potential. (orig.)

Microbial Production of Malic Acid from Biofuel-Related Coproducts and Biomass

Directory of Open Access Journals (Sweden)

Thomas P. West

2017-04-01

Full Text Available The dicarboxylic acid malic acid synthesized as part of the tricarboxylic acid cycle can be produced in excess by certain microorganisms. Although malic acid is produced industrially to a lesser extent than citric acid, malic acid has industrial applications in foods and pharmaceuticals as an acidulant among other uses. Only recently has the production of this organic acid from coproducts of industrial bioprocessing been investigated. It has been shown that malic acid can be synthesized by microbes from coproducts generated during biofuel production. More specifically, malic acid has been shown to be synthesized by species of the fungus Aspergillus on thin stillage, a coproduct from corn-based ethanol production, and on crude glycerol, a coproduct from biodiesel production. In addition, the fungus Ustilago trichophora has also been shown to produce malic acid from crude glycerol. With respect to bacteria, a strain of the thermophilic actinobacterium Thermobifida fusca has been shown to produce malic acid from cellulose and treated lignocellulosic biomass. An alternate method of producing malic acid is to use agricultural biomass converted to syngas or biooil as a substrate for fungal bioconversion. Production of poly(β-l-malic acid by strains of Aureobasidium pullulans from agricultural biomass has been reported where the polymalic acid is subsequently hydrolyzed to malic acid. This review examines applications of malic acid, metabolic pathways that synthesize malic acid and microbial malic acid production from biofuel-related coproducts, lignocellulosic biomass and poly(β-l-malic acid.

Removal of Cr(VI) from aqueous solution by fungal biomass

Energy Technology Data Exchange (ETDEWEB)

Ahluwalia, Sarabjeet Singh [Department of Biotechnology, General Shivdev Singh Diwan Gurbachan Singh Khalsa College, Patiala, Punjab (India); Goyal, Dinesh [Department of Biotechnology and Environmental Sciences, Thapar University, Patiala, Punjab (India)

2010-10-15

Chromium compounds are released by industrial processes including leather production, mining, petroleum refining, in textile industry and dyeing. They are a significant threat to the environment and public health because of their toxicity. Removal of hexavalent chromium by living biomass of different fungi was effective in the order of Aspergillus terricola>Aspergillus niger>Acremonium strictum>Aureobasidium pullulans>Paecilomyces variotii>Aspergillus foetidus>Cladosporium resinae>Phanerochaete chrysosporium. Non-living dried fungal biomass showed higher potential for metal removal than living cells. Among all fungi dead biomass of P. chrysosporium, C. resinae and P. variotii had the maximum specific chromium uptake capacity, which was 11.02, 10.69 and 10.35 mg/g of dry biomass respectively at pH 4.0-5.0 in batch sorption. Removal of Cr(VI) by P. chrysosporium from multi-metallic synthetic solution as well as chrome effluent was significant by bringing down the residual concentration to 0.1 mg/L in the effluent, which falls within the permissible range and its removal was not affected by the presence of other metal ions such as Fe, Zn and Ni. Fourier transform infrared spectral analysis revealed the presence of carboxylate (C=O) and amine (-NH{sup +}{sub 3}-NH{sup +}{sub 2}) functional groups commonly present on the cell surface of all fungi, with possible involvement in chromium binding. The result indicates that non-living fungal biomass either obtained as a by-product of fermentation industry or mass produced using inexpensive culture media can be used for bioremediation of Cr(VI) from chrome effluent on large scale. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Microstructure analyses and thermoelectric properties of Ag1−xPb18Sb1+yTe20

International Nuclear Information System (INIS)

Perlt, S.; Höche, Th.; Dadda, J.; Müller, E.; Bauer Pereira, P.; Hermann, R.; Sarahan, M.; Pippel, E.; Brydson, R.

2012-01-01

This study reports microstructural investigations of long-term annealed Ag 1−x Pb m Sb 1+y Te 2+m (m=18, x=y=0, hereinafter referred to as AgPb 18 SbTe 20 ) (Lead–Antimony–Silver–Tellurium, LAST-18) as well as of Ag 1−x Pb 18 Sb 1+y Te 20 , i.e. Ag-deficient and Sb-excess LAST-18 (x≠0,y≠0), respectively. Two different length scales are explored. The micrometer scale was evaluated by SEM to analyze the volume fraction and the number of secondary phases as well as the impact of processing parameters on the homogeneity of bulk samples. For AgPb 18 SbTe 20 , site-specific FIB liftout of TEM lamellae from thermoelectrically characterized samples was accomplished to investigate the structure on the nanometer scale. High-resolution TEM and energy-filtered TEM were performed to reveal shape and size distribution of nanoprecipitates, respectively. A hypothesis concerning the structure–property relationship is set out within the frame of a gradient annealing experiment. This study is completed by results dealing with inhomogeneities on the micrometer scale of Ag 1−x Pb 18 Sb 1+y Te 20 and its electronic properties. Highlights: ► SEM and TEM microstructure investigation of long-term annealed AgPb 18 SbTe 20 . ► SEM and thermoelectric studies on Ag 1−x Pb 18 Sb 1+y Te 20 . ► Discussion concerning structure–property relationship in long-term annealed AgPb 18 SbTe 20 . ► Correlation between Ag 1−x Pb 18 Sb 1+y Te 20 microscale structure and electronic properties.

DIVERSIDAD DE LEVADURAS ASOCIADAS A INFLORESCENCIAS DE MANGO Y FLORES DE 'LULO ARBÓREO' DIVERSIDADE DE LEVEDURAS ASSOCIADAS A INFLORESCÊNCIAS DE MANGA E FLORES DE 'LULO ARBÓREO' YEAST DIVERSITY ASSOCIATED TO INFLORESCENCES OF MANGO AND FLOWERS OF 'LULO ARBOREO'

Directory of Open Access Journals (Sweden)

JACKELINE GAVIRIA V.

2012-12-01

Full Text Available En Colombia, el conocimiento de levaduras ha sido limitado a especies de interés clínico. El micro-hábitat aéreo de las flores, presenta un área de gran interés para el aislamiento de levaduras con importancia en el campo industrial, por su potencial uso como controlador biológico. El objetivo de este trabajo es analizar la diversidad de levaduras asociadas a inflorescencia de Mango (Mangífera índica y flores de Lulo arbóreo (Solanum wrightii. Para dicha finalidad se trabajó con 96 aislados, a los cuales se les realizó caracterización fenotípica y posteriores pruebas de MSP-PCR Fingerprinting. Estas pruebas fueron complementadas con amplificación parcial y secuenciación del segmento 26S del ADNr para identificación a nivel de especie. El patrón de diversidad encontrado refleja una dominancia de la especie Candida leandrae en flores de lulo arbóreo, también se presentaron especies como Cryptococcus laurentii, Candida parazyma, Aeurobasidium pullulans y Pseudozyma tsukubaensis. Las inflorescencias de mango presentaron especies como Sydowia eucalypti, Cryptococcus flavescens, C. laurentii, C. nemorosus, C. heveanensis, Pichia kluyveri, Pseudozyma tsukubaensis y Candida asparagi. Se logró identificar hasta el nivel taxonómico de especie el total de los aislados encontrados, además se hallaron especies con potencial uso biotecnológico.Na Colômbia, o conhecimento das leveduras é limitado a espécies de interesse clinico. O micro-habitat aéreo das flores apresenta um interessante campo para o isolamento de leveduras com importância na indústria pelo seu potencial uso em controle biológico. O objetivo deste trabalho foi analisar a diversidade de leveduras associadas a inflorescências de Manga (Mangifera indica e flores de 'lulo' (Solanum wrightii. Para isso, foram analisados 96 isolados, que foram caracterizados com testes fenotípicos e MSP-PCR Fingerprinting complementadas com sequenciamento parcial da região 26S do r

Effects of artificial holes in very large single-grain Y{sub 1.5}Ba{sub 2}Cu{sub 3}O{sub 7-y} bulk superconductors

Energy Technology Data Exchange (ETDEWEB)

Park, S. D.; Jun, B. H.; Kim, C. J. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, H. W. [Korea University of Technology and Education, Cheonan (Korea, Republic of)

2017-09-15

The effects of artificial holes on the trapped magnetic fields and magnetic levitation forces of very large single-grain Y{sub 1.5}Ba{sub 2}Cu{sub 3}O{sub 7-y} (Y1.5) bulk superconductors were studied. Artificial holes were made for Y1.5 powder compacts by die pressing using cylindrical dies with a diameter of 30 mm or 40 m, or rectangular dies with a side length of 50 mm. The single grain Y1.5 bulk superconductors (25 mm, 33 mm in diameter and 42 mm in side length) with artificial holes were fabricated using a top-seeded melt growth (TSMG) process for the die-pressed Y1.5 powder compacts. The magnetic levitation forces at 77 K of the 25 mm single grain Y1.5 samples with one (diameters of 4.2 mm) or six artificial holes (diameters of 2.5 mm) were 10-17% higher than that of the Y1.5 sample without artificial holes. The trapped magnetic fields at 77 K of the Y1.5 samples with artificial holes were also 9.6-18% higher than that of the Y1.5 sample without artificial holes. The 33 mm and 42 mm single grain Y1.5 samples with artificial holes (2.5 mm and 4.2 mm in diameter) also showed trapped magnetic fields 10-13% higher than that of the Y1.5 samples without artificial holes in spite of the reduced superconducting volume fraction due to the presence of artificial holes. The property enhancement in the large single grain Y1.5 bulk superconductors appears to be attributed to the formation of the pore-free regions near the artificial holes and the homogeneous oxygen distribution in the large Y123 grains.

Influence of roadside pollution on the phylloplane microbial community of Alnus nepalensis (Betulaceae

Directory of Open Access Journals (Sweden)

S.R Joshi

2008-09-01

Aureobasidium pollulans, Fusarium oxysporum and Mortierella sp. in the polluted site may be due to their resistance to pollutants in roadside conditions. Rev. Biol. Trop. 56 (3: 1521-1529. Epub 2008 September 30.La región nororiental de la India está experimentando un rápido desarrollo industrial y debido a la topografía montañosa de la región, los automóviles descargan variedad de contaminantes. Actividades humanas como moler piedra y construir caminos también aumentan el polvo atmosférico y la contaminación con metales pesados. Este estudio compara microorganismos en superficies foliares del árbol Alnus nepalensis (Betulaceae. Se estudió uno sitio en una intersección de Shillong, con alta densidad de tráfico (8 000-9 000 vehículos pesados/día, tomada como el sitio contaminado, y otro en un bosque aproximadamente a 500 m de la carretera (sitio no contaminado. Se contabilizaron bacterias, hongos, plomo, zinc, cobre, cadmio y sulfuro. La población bacteriana era más alta en el sitio no contaminado. La población bacteriana mostró una correlación negativa significativa con el contenido de plomo, cinc, cobre, cadmio y sulfuro foliares en el sitio contaminado, mientras que en el sitio no contaminado la correlación fue insignificante. La población de hongos también fue más alta en el sitio no contaminado. Un total de 29 especies de hongos fueron aislados A. nepalensis: 16 en el sitio contaminado y 28 en el no contaminado. Algunas especies de hongos como Mortierella sp., Fusarium oxysporum y Aureobasidium pollulans fueron dominantes en el sitio contaminado. El número de hongos y bacterias fue significativamente menor en el sitio contaminado. El coeficiente de correlación indicó un efecto perjudicial de metales como el plomo, el zinc, el cobre, el cadmio y el sulfuro en esta comunidad que habitan superficies de hojas. La especificidad de ciertos hongos al sitio no contaminado se puede atribuir a su sensibilidad a la contaminación. El predominio de

Electrical conductivity and reaction with lithium of LiFe{sub 1-y}Mn{sub y}PO{sub 4} olivine-type cathode materials

Energy Technology Data Exchange (ETDEWEB)

Molenda, J.; Ojczyk, W.; Marzec, J. [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland)

2007-12-06

Structural, electrical and electrochemical properties of Mn-substituted phospho-olivines LiFe{sub 1-y}Mn{sub y}PO{sub 4} were investigated and compared to those of LiFePO{sub 4}. Rietvield refined XRD patterns taken in the course of delithiation process showed apparent difference between phase compositions of these cathode materials upon lithium extraction. Contrary to the LiFePO{sub 4} and LiMnPO{sub 4} compositions for which a two-phase mechanism of electrochemical lithium extraction/insertion is observed, in case of Mn-substituted LiFe{sub 1-y}Mn{sub y}PO{sub 4} samples a single-phase mechanism of deintercalation was observed in the studied range of lithium concentration. Electrochemical characterization of the cathode materials were performed in Li/Li{sup +}/Li{sub x}Fe{sub 1-y}Mn{sub y}PO{sub 4}-type cells for y = 0.0, 0.25, 0.55, 0.75 and 1.0 compositions. Voltammery studies showed low reversibility of the lithium extraction process in the high-voltage ''manganese'' range, while in the ''iron'' range the reversibility of lithium extraction is high. Impedance measurements of the LiFe{sub 1-y}Mn{sub y}PO{sub 4} cathode materials, which enabled separation of the ionic and electronic components of their entire electrical conductivity, showed distinct influence of Mn content on the electronic part of conductivity. EIS measurements performed at different states of cell charge revealed that the charge-transfer impedance in Li{sub x}Fe{sub 1-y}Mn{sub y}PO{sub 4} is much lower than that of Li{sub x}FePO{sub 4}. (author)

Dispersal, density dependence, and population dynamics of a fungal microbe on leaf surfaces.

Science.gov (United States)

Woody, Scott T; Ives, Anthony R; Nordheim, Erik V; Andrews, John H

2007-06-01

Despite the ubiquity and importance of microbes in nature, little is known about their natural population dynamics, especially for those that occupy terrestrial habitats. Here we investigate the dynamics of the yeast-like fungus Aureobasidium pullulans (Ap) on apple leaves in an orchard. We asked three questions. (1) Is variation in fungal population density among leaves caused by variation in leaf carrying capacities and strong density-dependent population growth that maintains densities near carrying capacity? (2) Do resident populations have competitive advantages over immigrant cells? (3) Do Ap dynamics differ at different times during the growing season? To address these questions, we performed two experiments at different times in the growing season. Both experiments used a 2 x 2 factorial design: treatment 1 removed fungal cells from leaves to reveal density-dependent population growth, and treatment 2 inoculated leaves with an Ap strain engineered to express green fluorescent protein (GFP), which made it possible to track the fate of immigrant cells. The experiments showed that natural populations of Ap vary greatly in density due to sustained differences in carrying capacities among leaves. The maintenance of populations close to carrying capacities indicates strong density-dependent processes. Furthermore, resident populations are strongly competitive against immigrants, while immigrants have little impact on residents. Finally, statistical models showed high population growth rates of resident cells in one experiment but not in the other, suggesting that Ap experiences relatively "good" and "bad" periods for population growth. This picture of Ap dynamics conforms to commonly held, but rarely demonstrated, expectations of microbe dynamics in nature. It also highlights the importance of local processes, as opposed to immigration, in determining the abundance and dynamics of microbes on surfaces in terrestrial systems.

Sequence-based analysis of the Vitis vinifera L. cv Cabernet Sauvignon grape must mycobiome in three South African vineyards employing distinct agronomic systems

Directory of Open Access Journals (Sweden)

MATHABATHA EVODIA SETATI

2015-11-01

Full Text Available Recent microbiomic research of agricultural habitats has highlighted tremendous microbial biodiversity associated with such ecosystems. Data generated in vineyards have furthermore highlighted significant regional differences in vineyard biodiversity, hinting at the possibility that such differences might be responsible for regional differences in wine style and character, a hypothesis referred to as microbial terroir. The current study further contributes to this body of work by comparing the mycobiome associated with South African (SA Cabernet Sauvignon grapes in three neighboring vineyards that employ different agronomic approaches, and comparing the outcome with similar data sets from Californian vineyards. The aim of this study was to fully characterize the mycobiomes associated with the grapes from these vineyards. The data revealed approximately 10 times more fungal diversity than what is typically retrieved from culture-based studies. The Biodynamic vineyard was found to harbor a more diverse fungal community (H = 2.6 than the conventional (H = 2.1 and integrated (H = 1.8 vineyards. The data show that ascomycota are the most abundant phylum in the three vineyards, with Aureobasidium pullulans and its close relative Kabatiella microsticta being the most dominant fungi. This is the first report to reveal a high incidence of K. microsticta in the grape/wine ecosystem. Different common wine yeast species, such as Metschnikowia pulcherrima and Starmerella bacillaris dominated the mycobiome in the three vineyards. The data show that the filamentous fungi are the most abundant community in grape must although they are not regarded as relevant during wine fermentation. Comparison of metagenomic datasets from the three SA vineyards and previously published data from Californian vineyards revealed only 25% of the fungi in the SA dataset was also present in the Californian dataset, with greater variation evident amongst ubiquitous epiphytic fungi.

Sequence-based Analysis of the Vitis vinifera L. cv Cabernet Sauvignon Grape Must Mycobiome in Three South African Vineyards Employing Distinct Agronomic Systems.

Science.gov (United States)

Setati, Mathabatha E; Jacobson, Daniel; Bauer, Florian F

2015-01-01

Recent microbiomic research of agricultural habitats has highlighted tremendous microbial biodiversity associated with such ecosystems. Data generated in vineyards have furthermore highlighted significant regional differences in vineyard biodiversity, hinting at the possibility that such differences might be responsible for regional differences in wine style and character, a hypothesis referred to as "microbial terroir." The current study further contributes to this body of work by comparing the mycobiome associated with South African (SA) Cabernet Sauvignon grapes in three neighboring vineyards that employ different agronomic approaches, and comparing the outcome with similar data sets from Californian vineyards. The aim of this study was to fully characterize the mycobiomes associated with the grapes from these vineyards. The data revealed approximately 10 times more fungal diversity than what is typically retrieved from culture-based studies. The Biodynamic vineyard was found to harbor a more diverse fungal community (H = 2.6) than the conventional (H = 2.1) and integrated (H = 1.8) vineyards. The data show that ascomycota are the most abundant phylum in the three vineyards, with Aureobasidium pullulans and its close relative Kabatiella microsticta being the most dominant fungi. This is the first report to reveal a high incidence of K. microsticta in the grape/wine ecosystem. Different common wine yeast species, such as Metschnikowia pulcherrima and Starmerella bacillaris dominated the mycobiome in the three vineyards. The data show that the filamentous fungi are the most abundant community in grape must although they are not regarded as relevant during wine fermentation. Comparison of metagenomic datasets from the three SA vineyards and previously published data from Californian vineyards revealed only 25% of the fungi in the SA dataset was also present in the Californian dataset, with greater variation evident amongst ubiquitous epiphytic fungi.

Heterojunction laser operation of N-free and N-doped GaAs/sub 1-y/P/sub y/ (y=0.42--0.43, lambdaapprox.6200 A, 77 degreeK) near the direct-indirect transition (yapprox.y/subc/approx. =0.46)

International Nuclear Information System (INIS)

Coleman, J.J.; Holonyak, N. Jr.; Ludowise, M.J.; Wright, P.D.; Groves, W.O.; Keune, D.L.; Craford, M.G.

1975-01-01

The successful LPE growth of In/sub 1-x/Ga/sub x/P/sub 1-z/As/sub z//GaAs/sub 1-y/P/sub y/ single heterojunctions on VPE substrates makes possible the study of stimulated emission in N-free and N-doped GaAs/sub 1-y/P/sub y/ in a region (y=0.42--0.43) much closer to the direct-indirect transition (yequivalenty/subc/=0.46, 77 degreeK) than previously. Laser operation in N-free GaAs/sub 1-y/P/sub y/ on the GAMMA-Zn (E/sub Gamma/-E)) recombination transition has been achieved at energies as high as 2.00 eV (lambda=6200 A), and some line narrowing has been observed at energies as high as 2.01 eV (lambda=6170 A, y=0.43). In contrast to diodes made on lower composition substrates, the diodes of this work do not change their threshold current densities in the range 77--4.2 degreeK, indicating that laser operation occurs on direct transitions lying within approx.kT of the indirect donor states (Te) associated with the X conduction-band minima. From E/sub Gamma/+kTapprox.E/subX/-E/subd/ (y=0.42- []0.43), the depth of indirect Te donor states in GaAs/sub 1-y/P/sub y/ is estimated to fall in the range E/subd/=22--32 meV. Nitrogen doping in these laser diodes increases the threshold current densities since the N impurity is an efficient trap and introduces competing indirect recombination. For y=0.42--0.43 GaAs/sub 1-y/P/sub y/, heterojunction laser operation on the N trap lies approx.10 meV lower in energy than on the GAMMA-Zn transition. Beyond y=0.42--0.43, the N trap may be required for stimulated emission, but in this range diode operation at high currents becomes difficult because of the large change in carrier mobility

The electronic and optical properties of quaternary GaAs1-x-y N x Bi y alloy lattice-matched to GaAs: a first-principles study.

Science.gov (United States)

Ma, Xiaoyang; Li, Dechun; Zhao, Shengzhi; Li, Guiqiu; Yang, Kejian

2014-01-01

First-principles calculations based on density functional theory have been performed for the quaternary GaAs1-x-y N x Bi y alloy lattice-matched to GaAs. Using the state-of-the-art computational method with the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, electronic, and optical properties were obtained, including band structures, density of states (DOSs), dielectric function, absorption coefficient, refractive index, energy loss function, and reflectivity. It is found that the lattice constant of GaAs1-x-y N x Bi y alloy with y/x =1.718 can match to GaAs. With the incorporation of N and Bi into GaAs, the band gap of GaAs1-x-y N x Bi y becomes small and remains direct. The calculated optical properties indicate that GaAs1-x-y N x Bi y has higher optical efficiency as it has less energy loss than GaAs. In addition, it is also found that the electronic and optical properties of GaAs1-x-y N x Bi y alloy can be further controlled by tuning the N and Bi compositions in this alloy. These results suggest promising applications of GaAs1-x-y N x Bi y quaternary alloys in optoelectronic devices.

SEVILLA Y EL SEVILLA 1 (1972-2015 / Seville and the Seville 1(1972-2015

Directory of Open Access Journals (Sweden)

Valentín Trillo Martínez

2015-05-01

Full Text Available RESUMEN En 2012 el edificio de oficinas Sevilla 1 cumplía cuarenta años desde su inauguración. Obra de Fernando Villanueva, Manuel Trillo y Luis Fernando Gómez-Estern, arquitectos de la firma OTAISA, fue pionero en la ciudad en cuanto a su funcionalidad exclusiva, concepto de espacio de trabajo diáfano y técnica constructiva utilizada, basada en el empleo riguroso de un módulo de fachada en hormigón prefabricado con el que se controló la totalidad de la envolvente del inmueble. Después de este tiempo, en un entorno urbano muy evolucionado y consolidado, el edificio sigue teniendo un aspecto saludable. Su estudio y análisis subrayaran la importancia del edificio en el crecimiento de la ciudad y en el prolífico periodo de la oficina de arquitectura OTAISA que ocupó su onceava planta durante nueves años. Dirigida por Felipe Medina, oficina de arquitectura extensa y plural, importó la manera americana de entender la profesión como empresa, persiguiendo el equilibrio de la calidad, la capacidad y del rendimiento. Sus relaciones con una incipiente Escuela de Arquitectura sevillana, en una aún pequeña ciudad poco profesionalizada, resultaron inevitables.

Cell-specific expression of calcineurin immunoreactivity within the rat basolateral amygdala complex and colocalization with the neuropeptide Y Y1 receptor.

Science.gov (United States)

Leitermann, Randy J; Sajdyk, Tammy J; Urban, Janice H

2012-10-01

Neuropeptide Y (NPY) produces potent anxiolytic effects via activation of NPY Y1 receptors (Y1r) within the basolateral amygdaloid complex (BLA). The role of NPY in the BLA was recently expanded to include the ability to produce stress resilience and long-lasting reductions in anxiety-like behavior. These persistent behavioral effects are dependent upon activity of the protein phosphatase, calcineurin (CaN), which has long been associated with shaping long-term synaptic signaling. Furthermore, NPY-induced reductions in anxiety-like behavior persist months after intra-BLA delivery, which together indicate a form of neuronal plasticity had likely occurred. To define a site of action for NPY-induced CaN signaling within the BLA, we employed multi-label immunohistochemistry to determine which cell types express CaN and if CaN colocalizes with the Y1r. We have previously reported that both major neuronal cell populations in the BLA, pyramidal projection neurons and GABAergic interneurons, express the Y1r. Therefore, this current study evaluated CaN immunoreactivity in these cell types, along with Y1r immunoreactivity. Antibodies against calcium-calmodulin kinase II (CaMKII) and GABA were used to identify pyramidal neurons and GABAergic interneurons, respectively. A large population of CaN immunoreactive cells displayed Y1r immunoreactivity (90%). Nearly all (98%) pyramidal neurons displayed CaN immunoreactivity, while only a small percentage of interneurons (10%) contained CaN immunoreactivity. Overall, these anatomical findings provide a model whereby NPY could directly regulate CaN activity in the BLA via activation of the Y1r on CaN-expressing, pyramidal neurons. Importantly, they support BLA pyramidal neurons as prime targets for neuronal plasticity associated with the long-term reductions in anxiety-like behavior produced by NPY injections into the BLA. Copyright © 2012 Elsevier B.V. All rights reserved.

Insertion of a specific fungal 3'-phosphoadenosine-5'-phosphatase motif into a plant homologue improves halotolerance and drought tolerance of plants.

Science.gov (United States)

Gašparič, Meti Buh; Lenassi, Metka; Gostinčar, Cene; Rotter, Ana; Plemenitaš, Ana; Gunde-Cimerman, Nina; Gruden, Kristina; Zel, Jana

2013-01-01

Soil salinity and drought are among the most serious agricultural and environmental problems of today. Therefore, investigations of plant resistance to abiotic stress have received a lot of attention in recent years. In this study, we identified the complete coding sequence of a 3'-phosphoadenosine-5'-phosphatase protein, ApHal2, from the halotolerant yeast Aureobasidium pullulans. Expression of the ApHAL2 gene in a Saccharomyces cerevisiae hal2 mutant complemented the mutant auxotrophy for methionine, and rescued the growth of the hal2 mutant in media with high NaCl concentrations. A 21-amino-acids-long region of the ApHal2 enzyme was inserted into the Arabidopsis thaliana homologue of Hal2, the SAL1 phosphatase. The inserted sequence included the META motif, which has previously been implicated in increased sodium tolerance of the Hal2 homologue from a related fungal species. Transgenic Arabidopsis plants overexpressing this modified SAL1 (mSAL1) showed improved halotolerance and drought tolerance. In a medium with an elevated salt concentration, mSAL1-expressing plants were twice as likely to have roots in a higher length category in comparison with the wild-type Arabidopsis and with plants overexpressing the native SAL1, and had 5% to 10% larger leaf surface area under moderate and severe salt stress, respectively. Similarly, after moderate drought exposure, the mSAL1-expressing plants showed 14% increased dry weight after revitalisation, with no increase in dry weight of the wild-type plants. With severe drought, plants overexpressing native SAL1 had the worst rehydration success, consistent with the recently proposed role of SAL1 in severe drought. This was not observed for plants expressing mSAL1. Therefore, the presence of this fungal META motif sequence is beneficial under conditions of increased salinity and moderate drought, and shows no drawbacks for plant survival under severe drought. This demonstrates that adaptations of extremotolerant fungi should

Microstrain engineered magnetic properties in Bi1-x Ca x Fe1-y Ti y O3-δ nanoparticles: deviation from Néel’s 1/d size-dependent magnetization behaviour

Science.gov (United States)

Mocherla, Pavana S. V.; Sahana, M. B.; Gopalan, R.; Ramachandra Rao, M. S.; Nanda, B. R. K.; Sudakar, C.

2017-10-01

Magnetization of antiferromagnetic nanoparticles is known to generally scale up inversely to their diameter (d) according to Néel’s model. Here we report a deviation from this conventional linear 1/d dependence, altered significantly by the microstrain, in Ca and Ti substituted BiFeO3 nanoparticles. Magnetic properties of microstrain-controlled Bi1-x Ca x Fe1-y Ti y O3-δ (y  =  0 and x  =  y) nanoparticles are analyzed as a function of their size ranging from 18 nm to 200 nm. A complex interdependence of doping concentration (x or y), annealing temperature (T), microstrain (ɛ) and particle size (d) is established. X-ray diffraction studies reveal a linear variation of microstrain with inverse particle size, 1/d nm-1 (i.e. ɛ · d  =  16.5 nm·%). A rapid increase in the saturation magnetization below a critical size d c ~ 35 nm, exhibiting a (1/d) α (α  ≈  2.6) dependence, is attributed to the influence of microstrain. We propose an empirical formula M \\propto (1/d)ɛ β (β  ≈  1.6) to highlight the contributions from both the size and microstrain towards the total magnetization in the doped systems. The magnetization observed in nanoparticles is thus, a result of the competing magnetic contribution from the terminated spin cycloid on the surface and counteracting microstrain present at a given size.

HIPERTENSIÓN Y EMBARAZO: UN ESTUDIO VASCULAR DE LOS RECEPTORES α1-ADRENÉRGICOS

OpenAIRE

Pérez Ordaz, Leticia

2012-01-01

Los receptores α1-adrenérgicos medan la contracción del musculo liso vascular. Son activados por catecolaminas, adrenalina y noradrenalina para inducir un incremento en la concentración de calcio intracelular. Tres subtipos de receptores α1-adrenérgicos forman esta familia (α1A, α1B y α1D). Cambios en la respuesta contráctil del musculo liso vascular han sido establecidos en hipertensión y embarazo, y cuando estos factores fueron individualmente evaluados, respuestas increme...

Architectural Processes and Physicochemical Properties of CoO/ZnO and Zn 1− x Co x O/Co 1− y Zn y O Nanocomposites

KAUST Repository

Yao, Ke Xin

2009-01-29

In this work we synthesized two inverse kinds of cobalt and zinc oxide nanocomposites (CoO/ZnO and Zn1-xCoxO/Co 1-yZnyO) and compared methodologistic features observed from the syntheses. The binary oxide system chosen herein is because divalent cobalt and zinc have very similar ion radii, and they interdiffuse easily when forming doped structures. A "two-pot" process was devised for the CoO/ZnO composites, in which mesocrystalline cores of CoO were formed first, followed by introduction of an overlayer of ZnO nanoparticles to the core surfaces. In contrast, a "one-pot" process was developed for the Zn1-xCoxO/Co1-yZnyO composites. In particular, hollow and/or multishelled Zn1-xCoxO cores (in wurtzite phase) serve as a support for the nanospheres of Co 1-yZnyO (in rock-salt phase) in this latter method. Our findings indicate that while "multi-pot" synthesis is a prevailing methodology for composite nanoparticles, simpler "one-pot" synthesis can be an effective approach for preparation of more complex nanocomposite materials, especially for interdoped metal oxides. As an example, our as-prepared binary oxide composites Zn1-xCoxO/Co 1-yZnyO have shown good catalytic activity for oxidation of carbon monoxide at relatively low reaction temperatures. © 2009 American Chemical Society.

MHEALTH Y TICS EN LOS CUIDADOS DE LA DIABETES MELLITUS TIPO 1

OpenAIRE

Ramos Fernández, Javier

2017-01-01

La diabetes mellitus tipo 1 es una enfermedad crónica consistente en un cuadro metabólico caracterizado por hiperglucemia mantenida, provocada por un déficit absoluto de insulina y por lo tanto, es necesaria su administración exógena; Constituye el 10% de los casos de diabetes en la población general, y se da en niños y adolescentes con gran diferencia (95%) 1. Debido a que es una enfermedad crónica, debemos realizar una educación precoz y profunda sobre los hábitos de vida de las personas di...

UPCSat-1: Desarrollo, integración y caracterización de los paneles solares y el sensor óptico

OpenAIRE

Pedret Otero, Alfred

2012-01-01

En este proyecto se detalla el proceso de montaje de los paneles solares del UPCSat-1, así como de los diferentes componentes y sensores que equipan estos paneles. Se ha realizado una detallada descripción del proceso y las técnicas utilizadas en el montaje, que ha permitido la detección de errores en el diseño y en los protocolos utilizados, obteniendo como resultado un proceso de montaje que garantiza el correcto funcionamiento de los paneles solares del UPCSat-1. Se pr...

Photocatalytic hydrogen generation over Eosin Y-Sensitized TS-1 zeolite

International Nuclear Information System (INIS)

Zhang Xiaojie; Jin Zhiliang; Li Yuexiang; Li Shuben; Lu Gongxuan

2008-01-01

Eosin Y-sensitized TS-1 zeolite was studied for the photo-reduction of water into hydrogen driven by visible light (λ ≥ 420 nm). The optimal pH and weight ratio between Eosin Y and TS-1 zeolite is 7 and 1/8, respectively. In the presence of triethanolamine (TEA) as an electron donor, the highest rate of hydrogen generation and apparent quantum efficiency are 34 μmol h -1 and 9.4%, respectively, under visible light irradiation (λ ≥ 420 nm). Short-term stability test indicates that the catalyst is rather stable during 50 h photoreaction

Photocatalytic hydrogen generation over Eosin Y-Sensitized TS-1 zeolite

Energy Technology Data Exchange (ETDEWEB)

Zhang Xiaojie [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100101 (China); Jin Zhiliang [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Li Yuexiang [Department of Chemistry, Nanchang University, Nanjing Road 245, Nanchang 330047 (China); Li Shuben [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China); Lu Gongxuan [State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Tianshui Zhong Road 18, Lanzhou 730000 (China)], E-mail: gxlu@lzb.ac.cn

2008-05-30

Eosin Y-sensitized TS-1 zeolite was studied for the photo-reduction of water into hydrogen driven by visible light ({lambda} {>=} 420 nm). The optimal pH and weight ratio between Eosin Y and TS-1 zeolite is 7 and 1/8, respectively. In the presence of triethanolamine (TEA) as an electron donor, the highest rate of hydrogen generation and apparent quantum efficiency are 34 {mu}mol h{sup -1} and 9.4%, respectively, under visible light irradiation ({lambda} {>=} 420 nm). Short-term stability test indicates that the catalyst is rather stable during 50 h photoreaction.

Distribution of impurity states and charge transport in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Liu, Yuanfeng; Makongo, Julien P.A. [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Page, Alexander [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Sahoo, Pranati [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Uher, Ctirad [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Stokes, Kevin [The Advanced Materials Research Institute, Department of Physics, University of New Orleans, New Orleans, LA 70148 (United States); Poudeu, Pierre F.P., E-mail: ppoudeup@umich.edu [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

2016-02-15

Energy filtering of charge carriers in a semiconducting matrix using atomically coherent nanostructures can lead to a significant improvement of the thermoelectric figure of merit of the resulting composite. In this work, several half-Heusler/full-Heusler (HH/FH) nanocomposites with general compositions Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} (0≤x≤0.15 and y=0.005, 0.01 and 0.025) were synthesized in order to investigate the behavior of extrinsic carriers at the HH/FH interfaces. Electronic transport data showed that energy filtering of carriers at the HH/FH interfaces in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} samples strongly depends on the doping level (y value) as well as the energy levels occupied by impurity states in the samples. For example, it was found that carrier filtering at HH/FH interfaces is negligible in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} (y=0.01 and 0.025) composites where donor states originating from Sb dopant dominate electronic conduction. However, we observed a drastic decrease in the effective carrier density upon introduction of HH/FH interfaces for the mechanically alloyed Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 0.995}Sb{sub 0.005} samples where donor states from unintentional Fe impurities contribute the largest fraction of conduction electrons. This work demonstrates the ability to synergistically integrate the concepts of doping and energy filtering through nanostructuring for the optimization of electronic transport in semiconductors. - Graphical abstract: Electronic transport in semiconducting half-Heusler (HH) matrices containing full-Heusler (FH) nanoinclusions strongly depends on the energy distribution of impurity states within the HH matrix with respect to the magnitude of the potential energy barrier at the HH/FH interfaces. - Highlights: • Coherent nanostructures enhanced thermoelectric behavior of half-Heusler alloys. • Nanostructures act as energy filter of

Central nervous system neuropeptide Y signaling via the Y1 receptor partially dissociates feeding behavior from lipoprotein metabolism in lean rats.

Science.gov (United States)

Rojas, Jennifer M; Stafford, John M; Saadat, Sanaz; Printz, Richard L; Beck-Sickinger, Annette G; Niswender, Kevin D

2012-12-15

Elevated plasma triglyceride (TG) levels contribute to an atherogenic dyslipidemia that is associated with obesity, diabetes, and metabolic syndrome. Numerous models of obesity are characterized by increased central nervous system (CNS) neuropeptide Y (NPY) tone that contributes to excess food intake and obesity. Previously, we demonstrated that intracerebroventricular (icv) administration of NPY in lean fasted rats also elevates hepatic production of very low-density lipoprotein (VLDL)-TG. Thus, we hypothesize that elevated CNS NPY action contributes to not only the pathogenesis of obesity but also dyslipidemia. Here, we sought to determine whether the effects of NPY on feeding and/or obesity are dissociable from effects on hepatic VLDL-TG secretion. Pair-fed, icv NPY-treated, chow-fed Long-Evans rats develop hypertriglyceridemia in the absence of increased food intake and body fat accumulation compared with vehicle-treated controls. We then modulated CNS NPY signaling by icv injection of selective NPY receptor agonists and found that Y1, Y2, Y4, and Y5 receptor agonists all induced hyperphagia in lean, ad libitum chow-fed Long-Evans rats, with the Y2 receptor agonist having the most pronounced effect. Next, we found that at equipotent doses for food intake NPY Y1 receptor agonist had the most robust effect on VLDL-TG secretion, a Y2 receptor agonist had a modest effect, and no effect was observed for Y4 and Y5 receptor agonists. These findings, using selective agonists, suggest the possibility that the effect of CNS NPY signaling on hepatic VLDL-TG secretion may be relatively dissociable from effects on feeding behavior via the Y1 receptor.

Tunable thermodynamic activity of La x Sr1-x Mn y Al1-y O3-δ (0 ≤ x ≤ 1, 0 ≤ y ≤ 1) perovskites for solar thermochemical fuel synthesis.

Science.gov (United States)

Ezbiri, M; Takacs, M; Theiler, D; Michalsky, R; Steinfeld, A

2017-02-28

Nonstoichiometric metal oxides with variable valence are attractive redox materials for thermochemical and electrochemical fuel processing. To guide the design of advanced redox materials for solar-driven splitting of CO 2 and/or H 2 O to produce CO and/or H 2 (syngas), we investigate the equilibrium thermodynamics of the La x Sr 1- x Mn y Al 1- y O 3- δ perovskite family (0 ≤ x ≤ 1, 0 ≤ y ≤ 1) and La 0.6 Ca 0.4 Mn 0.8 Al 0.2 O 3- δ , and compare them to those of CeO 2 as the baseline. Oxygen nonstoichiometry measurements from 1573 to 1773 K and from 0.206 to 180 mbar O 2 show a tunable reduction extent, increasing with increasing Sr content. Maximal nonstoichiometry of 0.32 is established with La 0.2 Sr 0.8 Mn 0.8 Al 0.2 O 3- δ at 1773 K and 2.37 mbar O 2 . As a trend, we find that oxygen capacities are most sensitive to the A-cation composition. Partial molar enthalpy, entropy and Gibbs free energy changes for oxide reduction are extracted from the experimental data using defect models for Mn 4+ /Mn 3+ and Mn 3+ /Mn 2+ redox couples. We find that perovskites exhibit typically decreasing enthalpy changes with increasing nonstoichiometries. This desirable characteristic is most pronounced by La 0.6 Sr 0.4 Mn 0.4 Al 0.6 O 3- δ , rendering it attractive for CO 2 and H 2 O splitting. Generally, perovskites show lower enthalpy and entropy changes than ceria, resulting in more favorable reduction but less favorable oxidation equilibria. The energy penalties due to larger temperature swings and excess oxidants are discussed in particular. Using electronic structure theory, we conclude with a practical methodology estimating thermodynamic activity to rationally design perovskites with variable stoichiometry and valence.

Adult exposure to tributyltin affects hypothalamic neuropeptide Y, Y1 receptor distribution, and circulating leptin in mice.

Science.gov (United States)

Bo, E; Farinetti, A; Marraudino, M; Sterchele, D; Eva, C; Gotti, S; Panzica, G

2016-07-01

Tributyltin (TBT), a pesticide used in antifouling paints, is toxic for aquatic invertebrates. In vertebrates, TBT may act in obesogen- inducing adipogenetic gene transcription for adipocyte differentiation. In a previous study, we demonstrated that acute administration of TBT induces c-fos expression in the arcuate nucleus. Therefore, in this study, we tested the hypothesis that adult exposure to TBT may alter a part of the nervous pathways controlling animal food intake. In particular, we investigated the expression of neuropeptide Y (NPY) immunoreactivity. This neuropeptide forms neural circuits dedicated to food assumption and its action is mediated by Y1 receptors that are widely expressed in the hypothalamic nuclei responsible for the regulation of food intake and energy homeostasis. To this purpose, TBT was orally administered at a dose of 0.025 mg/kg/day/body weight to adult animals [male and female C57BL/6 (Y1-LacZ transgenic mice] for 4 weeks. No differences were found in body weight and fat deposition, but we observed a significant increase in feed efficiency in TBT-treated male mice and a significant decrease in circulating leptin in both sexes. Computerized quantitative analysis of NPY immunoreactivity and Y1-related β-galactosidase activity demonstrated a statistically significant reduction in NPY and Y1 transgene expression in the hypothalamic circuit controlling food intake of treated male mice in comparison with controls. In conclusion, the present results indicate that adult exposure to TBT is profoundly interfering with the nervous circuits involved in the stimulation of food intake. © 2016 American Society of Andrology and European Academy of Andrology.

Scintillation properties of polycrystalline LaxY1-xO3 ceramic

Science.gov (United States)

Sahi, Sunil; Chen, Wei; Kenarangui, Rasool

2015-03-01

Scintillators are the material that absorbs the high-energy photons and emits visible photons. Scintillators are commonly used in radiation detector for security, medical imaging, industrial applications and high energy physics research. Two main types of scintillators are inorganic single crystals and organic (plastic or liquid) scintillators. Inorganic single crystals are expensive and difficult to grow in desire shape and size. Also, some efficient inorganic scintillator such as NaI and CsI are not environmental friendly. But on the other hand, organic scintillators have low density and hence poor energy resolution which limits their use in gamma spectroscopy. Polycrystalline ceramic can be a cost effective alternative to expensive inorganic single crystal scintillators. Here we have fabricated La0.2Y1.8O3 ceramic scintillator and studied their luminescence and scintillation properties. Ceramic scintillators were fabricated by vacuum sintering of La0.2Y1.8O3 nanoparticles at temperature below the melting point. La0.2Y1.8O3 ceramic were characterized structurally using XRD and TEM. Photoluminescence and radioluminescence studies were done using UV and X-ray as an excitation source. We have used gamma isotopes with different energy to studies the scintillation properties of La0.2Y1.8O3 scintillator. Preliminary studies of La0.2Y1.8O3 scintillator shows promising result with energy resolution comparable to that of NaI and CsI.

Structural and intrinsic Josephson properties of Bi{sub 2}Sr{sub 2}Ca{sub 1−y}Y{sub y}Cu{sub 2}O{sub 8+δ} single crystal

Energy Technology Data Exchange (ETDEWEB)

Yamaki, K., E-mail: kyamaki@cc.utsunomiya-u.ac.jp; Murata, K.; Irie, A.

2016-10-15

Highlights: • Single crystals of yttrium-doped BSCCO (BSCYCO) were grown by a self-flux method. • T{sub c} and c-axis lattice constant of BSCYCO were controlled by the substitution of Y. • A multibranch structure was observed up to y = 0.10 (Bi{sub 2}Sr{sub 2}Ca{sub 1−y}Y{sub y}Cu{sub 2}O{sub 8+δ}). • The BSCYCO mesa has higher maximum voltage compared with nondoped BSCCO. - Abstract: In this study, Bi{sub 2}Sr{sub 2}Ca{sub 1−y}Y{sub y}Cu{sub 2}O{sub 8+δ} (BSCYCO) single crystals with yttrium doping content of y = 0–0.30 were synthesized by a self-flux method. The critical temperature and c-axis lattice constant of BSCYCO were controlled by the substitution of yttrium at the calcium site. A 290 × 90 × 0.4 µm{sup 3} mesa structure was fabricated using photolithography and argon-ion milling. A multibranch structure in current–voltage characteristics was successfully observed for mesas of BSCYCO (y = 0–0.10). The critical current of intrinsic Josephson junctions (IJJs) in BSCYCO mesas was systematically investigated.

Acoplamiento molecular y actividad antibacteriana de las tioureas (R,R-N,N´-bis(1-ciclohexiletiltiourea y (R,R-N,N´-bis(1-feniletiltiourea

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Fabían Martínez Flores

2013-05-01

Full Text Available Las tioureas, son compuestos resultantes de sustituir el átomo de oxígeno de la urea (NH2CONH2 por un átomo de azufre (NH2CSNH2. Actualmente se ha visto que las tioureas presentan diversas actividades biológicas, dentro de las que se encuentra la antimicrobiana. En el presente estudio se evaluó la actividad antibacteriana mediante acoplamiento molecular entre la enzima DNA girasa (receptor y las tioureas (R, R-N,N´-bis(1 ciclohexiletiltiourea (CYTU1 y (R,R-N,N´-bis(1-feniletiltiourea (CYTU2 como ligando en busca del posible mecanismo de acción de estos compuestos, los resultados muestran que existe interacción entre la enzima y ambas tioureas en el sitio activo. Por otro lado, también se evaluó la actividad antibacteriana frente a cepas de Sthapylococcus aureus, Escherichia coli y Pseudomonas fluorescens, mediante el método de microdilución en caldo con la adición de bromuro de 3-(4,5-dimetil-2-tiazolil-2,5-difeniltetrazolium (MTT, como parte del ensayo de viabilidad, mostrando una disminución de la misma sólo contra las bacterias gram negativas, siendo la tiourea CYTU2 la que mostró mejor actividad antibacteriana. Molecular docking and antibacterial activity thioureas (R,R-N,N´-bis(1-cyclohexyethylthiourea and (R,R-N,N´-bis(1-phenylethylthiourea Abstract Thioureas are resultant compounds of substitute the oxygen atom from urea (NH2CONH2 for a sulfur atom (NH2CSNH2. There are evidential that show the biological activity of thioureas, within which are antibacterial activity. We studied the antibacterial activity of two thioureas (R,R-N,N´-bis(1 cyclohexylethylthiourea (CYTU1 y (R,R-N,N´-bis(1 phenylethylthiourea (CYTU2 in silico using Molecular Docking between the DNA gyrase enzyme (receptor and the two thioureas (ligand. The results showed interaction between DNA girase and both thioureas on the pocket of the enzyme. By other hand, the biological activity was evaluated against the following bacterial strains: Sthapylococcus

Mek1Y130C mice recapitulate aspects of human cardio-facio-cutaneous syndrome

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Aoidi, Rifdat; Houde, Nicolas; Landry-Truchon, Kim; Holter, Michael; Jacquet, Kevin; Charron, Louis; Yu, Benjamin D.; Rauen, Katherine A.; Bisson, Nicolas; Newbern, Jason

2018-01-01

ABSTRACT The RAS/MAPK signaling pathway is one of the most investigated pathways, owing to its established role in numerous cellular processes and implication in cancer. Germline mutations in genes encoding members of the RAS/MAPK pathway also cause severe developmental syndromes collectively known as RASopathies. These syndromes share overlapping characteristics, including craniofacial dysmorphology, cardiac malformations, cutaneous abnormalities and developmental delay. Cardio-facio-cutaneous syndrome (CFC) is a rare RASopathy associated with mutations in BRAF, KRAS, MEK1 (MAP2K1) and MEK2 (MAP2K2). MEK1 and MEK2 mutations are found in ∼25% of the CFC patients and the MEK1Y130C substitution is the most common one. However, little is known about the origins and mechanisms responsible for the development of CFC. To our knowledge, no mouse model carrying RASopathy-linked Mek1 or Mek2 gene mutations has been reported. To investigate the molecular and developmental consequences of the Mek1Y130C mutation, we generated a mouse line carrying this mutation. Analysis of mice from a Mek1 allelic series revealed that the Mek1Y130C allele expresses both wild-type and Y130C mutant forms of MEK1. However, despite reduced levels of MEK1 protein and the lower abundance of MEK1 Y130C protein than wild type, Mek1Y130C mutants showed increased ERK (MAPK) protein activation in response to growth factors, supporting a role for MEK1 Y130C in hyperactivation of the RAS/MAPK pathway, leading to CFC. Mek1Y130C mutant mice exhibited pulmonary artery stenosis, cranial dysmorphia and neurological anomalies, including increased numbers of GFAP+ astrocytes and Olig2+ oligodendrocytes in regions of the cerebral cortex. These data indicate that the Mek1Y130C mutation recapitulates major aspects of CFC, providing a new animal model to investigate the physiopathology of this RASopathy. This article has an associated First Person interview with the first author of the paper. PMID:29590634

Immersion vaccination against Yersinia ruckeri O1, biotype 2 confers cross protection against Y. ruckeri O1 biotype 1

DEFF Research Database (Denmark)

Raida, Martin Kristian; Neumann, Lukas; Kragelund Strøm, Helene

A new biotype 2 of Y. ruckeri O1, which lacks motility has proven highly virulent for rainbow trout, and is causing disease in cultured trout even in fish vaccinated with commercial ERM biotype 1 vaccines. Not much is known about immunity against biotype 2, and therefore have we produced a Y...... resulted in very low mortalities with no significant difference in mortality between vaccinated and mock-vaccinated fish. Challenge with biotype 1 resulted in a significantly lower mortality (P=0.0001) in the vaccinated group. This result was confirmed 15 months post vaccination (P... 2 confers significant cross protection against biotype 1....

Pullulan-coated phospholipid and Pluronic F68 complex nanoparticles for carrying IR780 and paclitaxel to treat hepatocellular carcinoma by combining photothermal therapy/photodynamic therapy and chemotherapy

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Wang D

2017-12-01

Full Text Available Dan Wang,1,* Sipei Zhang,1,* Tao Zhang,1 Guoyun Wan,1 Bowei Chen,1 Qingqing Xiong,2 Jie Zhang,3 Wenxue Zhang,4 Yinsong Wang1 1Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics (Theranostics, School of Pharmacy, Tianjin Medical University, 2Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, 3Surgery Department, 4Radiotherapy Department, Tianjin Medical University General Hospital, Tianjin, China *These authors contributed equally to this work Abstract: IR780, a near-infrared dye, can also be used as a photosensitizer both for photothermal therapy (PTT and photodynamic therapy (PDT. In this study, we designed a simple but effective nanoparticle system for carrying IR780 and paclitaxel, thus hoping to combine PTT/PDT and chemotherapy to treat hepatocellular carcinoma (HCC. This nanosystem, named PDF nanoparticles, consisted of phospholipid/Pluronic F68 complex nanocores and pullulan shells. IR780 and paclitaxel were loaded separately into PDF nanoparticles to form PDFI and PDFP nanoparticles, which had regular sphere shapes and relatively small sizes. Upon near-infrared laser irradiation at 808 nm, PDFI nanoparticles showed strong PTT/PDT efficacy both in vitro and in vivo. In MHCC-97H cells, the combined treatment of PDFI nanoparticles/laser irradiation and PDFP nanoparticles exhibited significant synergistic effects on inhibiting cell proliferation and inducing cell apoptosis and cell cycle arrest at G2/M phase. In MHCC-97H tumor-bearing mice, PDFI nanoparticles exhibited excellent HCC-targeting and accumulating capability after intravenous injection. Furthermore, the combined treatment of PDFI nanoparticles/laser irradiation and PDFP nanoparticles also effectively inhibited the tumor growth and the tumor angiogenesis in MHCC-97H tumor-bearing mice. In summary, we put forward a therapeutic

Expresionismo, racionalismo y arquitectura orgánica en Alemania y en Dinamarca: Häring y Scharoun; Jacobsen y Utzon

OpenAIRE

González Capitel, Antón

1996-01-01

1. Expresionismo, racionalismo y arquitectura orgánica en Alemania y en Dinamarca: Haring y Scharoun; Jacobsen y Utzon 1. 1. La obra tardía de Hugo Haring 1. 2. La integración del expresionismo y del organicismo en la obra de Scharoun 1. 2. 1. Los edificios escolares como lugares orgánicos 1. 2. 2. Los extremos de la complejidad formal en Scharoun. Uno: viviendas 1. 2. 3. Los extremos de la complejidad formal. Dos: varios auditorios y una biblioteca 1. 3. Continuidad ...

Functional and molecular evidence for heteromeric association of P2Y1 receptor with P2Y2 and P2Y4 receptors in mouse granulocytes.

Science.gov (United States)

Ribeiro-Filho, Antonio Carlos; Buri, Marcus Vinicius; Barros, Carlos Castilho; Dreyfuss, Juliana Luporini; Nader, Helena Bonciani; Justo, Giselle Zenker; Craveiro, Rogério Bastos; Pesquero, João Bosco; Miranda, Antonio; Ferreira, Alice Teixeira; Paredes-Gamero, Edgar Julian

2016-07-07

All hematopoietic cells express P2 receptors, however pharmacological characteristics such as expression and affinity in granulocytes are unknown. Pharmacological characteristics of P2 receptors were evaluated by Ca(2+) measurements using Fura-2 fluorophore. P2 receptors expression were analyzed by flow cytometry and RT-PCR. P2 interaction were shown by coimmunoprecipitation, western blotting and FRET. Granulocytes were responsive to P2Y agonists, whereas P2X agonists were ineffective. Ca(2+) increase, elicited by ADP and UTP was dependent on intracellular stocks and sensitive to G-coupled receptor inhibition. Moreover, MRS2179, a specific antagonist of the P2Y1 receptor, abolished ADP response. Interestingly, ADP and UTP exhibited full heterologous desensitization, suggesting that these agonists interact with the same receptor. The heteromeric association between P2Y1 receptor and the P2Y2 and P2Y4 receptors was shown by immunoprecipitation and FRET analysis. Clear evidence of heteromeric association of P2Y receptors was found during the evaluation of P2 receptors present in mice granulocytes, which could impact in the classical pharmacology of P2Y receptors in granulocytes.

Transformation of Astrocytes to a Neuroprotective Phenotype by Microglia via P2Y1 Receptor Downregulation

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Youichi Shinozaki

2017-05-01

Full Text Available Microglia and astrocytes become reactive following traumatic brain injury (TBI. However, the coordination of this reactivity and its relation to pathophysiology are unclear. Here, we show that microglia transform astrocytes into a neuroprotective phenotype via downregulation of the P2Y1 purinergic receptor. TBI initially caused microglial activation in the injury core, followed by reactive astrogliosis in the peri-injured region and formation of a neuroprotective astrocyte scar. Equivalent changes to astrocytes were observed in vitro after injury. This change in astrocyte phenotype resulted from P2Y1 receptor downregulation, mediated by microglia-derived cytokines. In mice, astrocyte-specific P2Y1 receptor overexpression (Astro-P2Y1OE counteracted scar formation, while astrocyte-specific P2Y1 receptor knockdown (Astro-P2Y1KD facilitated scar formation, suggesting critical roles of P2Y1 receptors in the transformation. Astro-P2Y1OE and Astro-P2Y1KD mice showed increased and reduced neuronal damage, respectively. Altogether, our findings indicate that microglia-astrocyte interaction, involving a purinergic signal, is essential for the formation of neuroprotective astrocytes.

Modelación molecular y variación estructural de las integrasas de dos retrovirus humanos: HTLV-I y VIH-1

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Felipe García Vallejo

2009-01-01

Materiales y métodos: Tanto la integrasa del HTLV-I como la del VIH-1 son proteínas compuestas por 288 residuos de aminoácidos. Se encontró un parecido de estructuras terciarias entre los dominios catalíticos de las IN de VIH-1, ASV y RSV con la del HTLVI. A partir de 103 secuencias completas de la integrasa del VIH-1 se registraron, en 46 codones, un total de 53 sustituciones que se localizaron en diferentes posiciones de la proteína nativa; las más frecuentes fueron: N27G (32,1%, A265V (30,1%, L101I (31,1% y T123A (27,0%. Ninguna de las sustituciones más frecuentemente encontradas generó un cambio en el plegamiento nativo de la correspondiente región. Conclusión: La estructura tridimensional del dominio central catalítico de la integrasa condicionaría su actividad y su relación con moléculas potencialmente inhibidoras. Las sustituciones observadas fueron neutrales sin alterar la estructura nativa. Los resultados obtenidos confirman que la integrasa es un nuevo y promisorio blanco para el desarrollo de terapias antirretrovirales más efectivas en el siglo xxi.

Compositional dependence of the band-gap of Ge{sub 1−x−y}Si{sub x}Sn{sub y} alloys

Energy Technology Data Exchange (ETDEWEB)

Wendav, Torsten, E-mail: wendav@physik.hu-berlin.de [AG Theoretische Optik & Photonik, Humboldt Universität zu Berlin, Newtonstr. 15, 12489 Berlin (Germany); Fischer, Inga A.; Oehme, Michael; Schulze, Jörg [Institut für Halbleitertechnik, Universität Stuttgart, Pfaffenwaldring 47, 70569 Stuttgart (Germany); Montanari, Michele; Zoellner, Marvin Hartwig; Klesse, Wolfgang [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Capellini, Giovanni [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Dipartimento di Scienze, Università Roma Tre, Viale Marconi 446, 00146 Roma (Italy); Driesch, Nils von den; Buca, Dan [Peter Grünberg Institute 9 (PGI 9) and JARA-Fundamentals of Future Information Technologies, Forschungszentrum Jülich, 52428 Jülich (Germany); Busch, Kurt [AG Theoretische Optik & Photonik, Humboldt Universität zu Berlin, Newtonstr. 15, 12489 Berlin (Germany); Max-Born-Institut, Max-Born-Str. 2 A, 12489 Berlin (Germany)

2016-06-13

The group-IV semiconductor alloy Ge{sub 1−x−y}Si{sub x}Sn{sub y} has recently attracted great interest due to its prospective potential for use in optoelectronics, electronics, and photovoltaics. Here, we investigate molecular beam epitaxy grown Ge{sub 1−x−y}Si{sub x}Sn{sub y} alloys lattice-matched to Ge with large Si and Sn concentrations of up to 42% and 10%, respectively. The samples were characterized in detail by Rutherford backscattering/channeling spectroscopy for composition and crystal quality, x-ray diffraction for strain determination, and photoluminescence spectroscopy for the assessment of band-gap energies. Moreover, the experimentally extracted material parameters were used to determine the SiSn bowing and to make predictions about the optical transition energy.

DINÁMICA FAMILIAR, ENVEJECIMIENTO Y DETERIORO FUNCIONAL EN MÉXICO 1

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Verónica Montes de Oca

2010-01-01

Full Text Available 1.Documento preparado para la II Conferencia intergubernamental sobre envejecimiento, Brasilia, Brasil, 4-6 de diciembre del 2007. El presente documento se inscribe en la discusión sobre las transformaciones que han experimentado las familias en México en el siglo XX, y como se asoman algunas dinámicas al interior que son resultado del alargamiento en la esperanza de vida individual y de la presencia de limitaciones funcionales en los miembros en edad avanzada. Se reflexiona sobre los cambios sociales y demográficos en los hogares, las estrategias de apoyo y cuidado hacia las personas adultas mayores con presencia de enfermedades y limitaciones funcionales a partir de cálculos realizados con base en la Encuesta Nacional sobre Salud y Envejecimiento (2001. Si bien hay un esfuerzo de las instituciones de salud y de los arreglos familiares para atender esta situación, este artículo permite mostrar la fuerza y debilidad del sistema de protección social en la procuración de cuidados y apoyos hacia las personas en la vejez con limitaciones funcionales. Presenta algunos retos y áreas de acción relevantes para las instituciones gubernamentales y no gubernamentales. La idea que se propone, con base en este análisis, es reaccionar activamente entre instituciones, familias y sociedad para apoyar a la vejez que experimenta el deterioro progresivo de sus facultades físicas y mentales. Palabras-claves: dinámica familiar; vejez; deterioro funcional.

Hormona luteinizante y actividad ovárica en respuesta a kisspeptina-10 y su asociación con IGF-1 y leptina en becerras pre-púberes

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Rubén Santos Echeverría

2014-01-01

Full Text Available Se evaluó el efecto de la kisspeptina-10 (Kiss-10, administrada repetidamente, sobre la liberación de LH y la actividad ovárica en becerras pre-púberes. Asimismo, se determinó la asociación de IGF-1 y leptina s éricas con dichos efectos. Catorce (14 becerras Holstein o Suizo Pardo por Cebú (11.2±0.2 meses de edad; 187.4±6.3 kg de peso, se asignaron aleatoriamente para recibir cada dos horas, durante tres días una aplicación i.v. de Ki ss-10 (Kisspeptina- 1 0; 5 μg/kg de peso; n=7 o solución salina fisiológica (Testigo, n=7. Se colectó sangre cada 15 min de las 0-6, 24-30 y 72-78 h, y cada 2 h hasta las 84 h. Cada aplicación de Kiss-10 fue seguida de un incremento de LH, cuya magn itud (área bajo la curva disminuyó ( P 0.05, y ninguna becerra manifestó actividad ovárica cíclica. Se concluye que la Kiss-10 administrada repetidamente a becerras pre-púberes es un estímulo suficiente para evocar incr ementos consistentes de LH, para inducir la ovulación y actividad lútea en animales con concentraciones séri cas elevadas de IGF-1 y bajas de leptina, pero no para inducir la ciclicidad estral.

Vigilancia en red de los serotipos y la susceptibilidad antimicrobiana de Salmonella spp., Shigella spp. Y Vibrio cholerae O1, 1997 - 1999

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Nélida Muñoz

2000-09-01

Full Text Available En 1997, el Grupo de Microbiología del INS estableció un programa en red con los Laboratorios de Salud Pública (LSP del país y el apoyo de la OPS, para la vigilancia de los principales patógenos causantes de enfermedad diarreica aguda. El objetivo fue conocer los serotipos y los patrones de resistencia antimicrobiana de Salmonella spp., Shigella spp. y Vibrio cholerae O1. Los aislamientos fueron confirmados de acuerdo con los esquemas de identificación bioquímica y serológica estandarizados y la determinación de la susceptibilidad antimicrobiana se realizó por la técnica de difusión de disco (Kirby-Bauer. De 1997 a 1999, participaron 22 LSP con el envio de 976 aislamientos, 96% de origen clínico y 4% de alimentos; 34% Salmonella spp., 23% Shigella spp. y 42% V. cholerae 01. La distribución por serotipo de Salmonella fue 39% S. Enteritidis, 27% S. Typhimurium, 9% grupo El, 5% S. Typhi y 20% otros serotipos; de los aislamientos de Shigella, 67% fueron S. grupo flexneriza, 30% S sonnei, 2% S. dysenteriae y 1% S. boydii. Para V. cholerae 01, 99% fue serotipo Ogawa. La susceptibilidad antimicrobiana determinó que 56% de los aislamientos de Salmonella eran resistentes y 22% multirresistentes, con un patrón predominante de ampicilina, tetraciclina y trimetoprim-sulfa (SXT. De los aislamientos de Shigella, 97% fueron resistentes y 57% multirresistentes, con un patrón de ampicilina, tetraciclina, cloranfenicol y SXT. No se observaron cambios en la susceptibilidad de V. cholerae O1. Este estudio enfatiza la importancia de continuar con el programa de vigilancia, para conocer la epidemiologia de la EDA en Colombia, darle un tratamiento óptimo a estas infecciones y poder diseñar programas para disminuir la diseminación de bacterias resistentes.

Las reglas angloamericanas de catalogación y la norma ISO 690 - 1 y 2

OpenAIRE

Campos Herrera, Airelys

2007-01-01

Se define la catalogación como etapa del ciclo de procesamiento de la información, así como sus diferencias con el proceso de descripción bibliográfica. Se comparan las reglas angloamericanas de catalogación, segunda edición, con las normas ISO 690 - 1 y 2 para la descripción bibliográfica con respecto a: organismo creador, finalidad, alcance, estructura, tipos de asientos, niveles de descripción y sintaxis. Cataloguing, a phase within the cycle of information processing, as well as its di...

Pre-diabetes augments neuropeptide Y1- and α1-receptor control of basal hindlimb vascular tone in young ZDF rats.

Directory of Open Access Journals (Sweden)

Nicole M Novielli

Full Text Available Peripheral vascular disease in pre-diabetes may involve altered sympathetically-mediated vascular control. Thus, we investigated if pre-diabetes modifies baseline sympathetic Y(1-receptor (Y(1R and α(1-receptor (α(1R control of hindlimb blood flow (Q(fem and vascular conductance (VC.Q(fem and VC were measured in pre-diabetic ZDF rats (PD and lean controls (CTRL under infusion of BIBP3226 (Y(1R antagonist, prazosin (α(1R antagonist and BIBP3226+prazosin. Neuropeptide Y (NPY concentration and Y(1R and α(1R expression were determined from hindlimb skeletal muscle samples.Baseline Q(fem and VC were similar between groups. Independent infusions of BIBP3226 and prazosin led to increases in Q(fem and VC in CTRL and PD, where responses were greater in PD (p<0.05. The percent change in VC following both drugs was also greater in PD compared to CTRL (p<0.05. As well, Q(fem and VC responses to combined blockade (BIBP3226+prazosin were greater in PD compared to CTRL (p<0.05. Interestingly, an absence of synergistic effects was observed within groups, as the sum of the VC responses to independent drug infusions was similar to responses following combined blockade. Finally, white and red vastus skeletal muscle NPY concentration, Y(1R expression and α(1R expression were greater in PD compared to CTRL.For the first time, we report heightened baseline Y(1R and α(1R sympathetic control of Q(fem and VC in pre-diabetic ZDF rats. In support, our data suggest that augmented sympathetic ligand and receptor expression in pre-diabetes may contribute to vascular dysregulation.

Luminescence properties of LiSr2Y1-xLnxO4 (Ln=Eu,Tb,Tm) (0≤x≤1)

International Nuclear Information System (INIS)

Kubota, S.; Suzuyama, Y.; Yamane, H.; Shimada, M.

1998-01-01

Investigations of the luminescence properties of LiSr 2 Y 1-x Eu x O 4 , LiSr 2 Y 1-x Tb x O 4 and LiSr 2 Y 1-x Tm x O 4 (0≤x≤1) at room temperature are reported. These samples were synthesized by a solid state reaction. The excitation spectra of Tb 3+ emission in LiSr 2 Y 1-x Tb x O 4 (0≤x≤1) consist of broad bands corresponding to a transition between the 4f 8 and 4f 7 5d 1 states of Tb 3+ . The maximum intensity is situated at about 318 nm. This is at a much longer wavelength than those of other Tb 3+ doped phosphors. This is explained by a large offset of the adiabatic potential curve of the 4f 7 5d 1 state. (orig.)

Crystalline electric field at the rare-earth sites in RxY1-xCo5+y compounds (R= Dy and Tb)

International Nuclear Information System (INIS)

Han Xiufeng; Jin Hanmin; Chen Hong; Guo Guanghua; Zhao Tiesong

1992-01-01

The magnetic properties of R x Y 1-x Co 5+y compounds are reproduced well by a calculation based on the single-ion model. The values of the exchange field H cx and crystalline-electric-field parameters A m n at the rare-earth ion sites in R x Y 1-x Co 5+y (R = Dy and Tb) are evaluated by fitting the calculations to the experiments. The experiments include the temperature dependence of the spontaneous magnetization, the temperature dependence of the normalized magnetic moments of the rare-earth ions, the temperature dependence of the cone angle, the magnetization curves along the crystal axes at 4.2 K, and the hyperfine field at the Dy ion site

QCD sum rules study of the JPC=1-- charmonium Y mesons

International Nuclear Information System (INIS)

Albuquerque, R.M.; Nielsen, M.

2009-01-01

We use QCD sum rules to test the nature of the recently observed mesons Y(4260), Y(4350) and Y(4660), assumed to be exotic four-quark (cc-bar qq-bar) or (cc-bar ss-bar) states with J PC =1 -- . We work at leading order in α s , consider the contributions of higher dimension condensates and keep terms which are linear in the strange quark mass m s . We find for the (cc-bar ss-bar) state a mass m Y =(4.65±0.10) GeV which is compatible with the experimental candidate Y(4660), while for the (cc-bar qq-bar) state we find a mass m Y =(4.49±0.11) GeV, which is still consistent with the mass of the experimental candidate Y(4350). With the tetraquark structure we are working we cannot explain the Y(4260) as a tetraquark state. We also consider molecular D s0 D-bar s * and D 0 D-bar * states. For the D s0 D-bar s * molecular state we get m D s0 D -bar s* =(4.42±0.10) GeV which is consistent, considering the errors, with the mass of the meson Y(4350) and for the D 0 D-bar* molecular state we get m D 0 D -bar*=(4.27±0.10) GeV in excellent agreement with the mass of the meson Y(4260)

Behavior of the irreversibility line in the new superconductor La{sub 1.5+x}Ba{sub 1.5+x-y}Ca{sub y}Cu{sub 3}O{sub z}

Energy Technology Data Exchange (ETDEWEB)

Parra Vargas, C.A. [Grupo de Fisica de Materiales, Escuela de Fisica, Universidad Pedagogica y Tecnologica de Colombia, Tunja (Colombia); Pimentel, J.L.; Pureur, P. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, RS (Brazil); Landinez Tellez, D.A. [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, AA 5997, Bogota DC (Colombia); Roa-Rojas, J., E-mail: carlos.parra@uptc.edu.co [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, AA 5997, Bogota DC (Colombia)

2012-08-15

The irreversibility properties of high-T{sub c} superconductors are of major importance for technological applications. For example, a high irreversibility magnetic field is a more desirable quality for a superconductor . The irreversibility line in the H-T plane is constituted by experimental points, which divides the irreversible and reversible behavior of the magnetization. The irreversibility lines for series of La{sub 1.5+x}Ba{sub 1.5+x-y}Ca{sub y}Cu{sub 3}O{sub z} polycrystalline samples with different doping were investigated. The samples were synthesized using the usual solid estate reaction method. Rietveld-type refinement of x-ray diffraction patterns permitted to determine the crystallization of material in a tetragonal structure. Curves of magnetization ZFC-FC for the system La{sub 1.5+x}Ba{sub 1.5+x-y}Ca{sub y}Cu{sub 3}O{sub z}, were measured in magnetic fields of the 10-20,000 Oe, and allowed to obtain the values for the irreversibility and critical temperatures. The data of irreversibility temperature allowed demarcating the irreversibility line, T{sub irr}(H). Two main lines are used for the interpretation of the irreversibility line: one of those which suppose that the vortexes are activated thermally and the other proposes that associated to T{sub irr} a phase transition occurs. The irreversibility line is described by a power law. The obtained results allow concluding that in the system La{sub 1.5+x}Ba{sub 1.5+x-y}Ca{sub y}Cu{sub 3}O{sub z} a characteristic bend of the Almeida-Thouless (AT) tendency is dominant for low fields and a bend Gabay-Toulouse (GT) behavior for high magnetic fields. This feature of the irreversibility line has been reported as a characteristic of granular superconductors and it corroborates the topological effects of vortexes mentioned by several authors .

Synthesis, crystal structure investigation and magnetism of the complex metal-rich boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) with Th{sub 7}Fe{sub 3}-type structure

Energy Technology Data Exchange (ETDEWEB)

Misse, Patrick R.N.; Mbarki, Mohammed [Institute of Inorganic Chemistry, RWTH Aachen University, 52066 Aachen (Germany); Fokwa, Boniface P.T., E-mail: boniface.fokwa@ac.rwth-aachen.de [Institute of Inorganic Chemistry, RWTH Aachen University, 52066 Aachen (Germany)

2012-08-15

Powder samples and single crystals of the new complex boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) have been synthesized by arc-melting the elements under purified argon atmosphere on a water-cooled copper crucible. The products, which have metallic luster, were structurally characterized by single-crystal and powder X-ray diffraction as well as EDX measurements. Within the whole solid solution range the hexagonal Th{sub 7}Fe{sub 3} structure type (space group P6{sub 3}mc, no. 186, Z=2) was identified. Single-crystal structure refinement results indicate the presence of chromium at two sites (6c and 2b) of the available three metal Wyckoff sites, with a pronounced preference for the 6c site. An unexpected Rh/Ru site preference was found in the Ru-rich region only, leading to two different magnetic behaviors in the solid solution: The Rh-rich region shows a temperature-independent (Pauli) paramagnetism whereas an additional temperature-dependent paramagnetic component is found in the Ru-rich region. - Graphical abstract: The new complex boride series Cr{sub x}(Rh{sub 1-y}Ru{sub y}){sub 7-x}B{sub 3} (x=0.88-1; y=0-1) has been synthesized by arc melting the elements under purified argon atmosphere. Beside the 3d/4d site preference within the whole solid solution, an unexpected Rh/Ru site preference was found in the Ru-rich region only, leading to two different magnetic behaviors: The Rh-rich region shows a temperature-independent (Pauli) paramagnetism whereas an additional temperature-dependent paramagnetic component is found in the Ru-rich region. Highlights: Black-Right-Pointing-Pointer Synthesis of a new boride series fulfilling Vegard Acute-Accent s rule. Black-Right-Pointing-Pointer 3d/4d site preference. Black-Right-Pointing-Pointer Unexpected Ru/Rh site preference. Black-Right-Pointing-Pointer Rh-rich region is Pauli paramagnetic. Black-Right-Pointing-Pointer Ru-rich region is Pauli and temperature-dependent paramagnetic.

Theoretical investigations on the magnetocaloric and barocaloric effects in Tb{sub y}Gd{sub (1−y)}Al{sub 2} series

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, P.O.; Alho, B.P.; Alvarenga, T.S.T.; Nóbrega, E.P. [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil); Carvalho, A.Magnus G. [Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo – UNIFESP, 12231-280 São José dos Campos, SP (Brazil); Instituto Nacional de Metrologia, Qualidade e Tecnologia – INMETRO, 25250-020 Duque de Caxias, RJ (Brazil); Sousa, V.S.R. de; Caldas, A.; Oliveira, N.A. de [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil); Ranke, P.J. von, E-mail: von.ranke@uol.com.br [Instituto de Física, Universidade do Estado do Rio de Janeiro – UERJ, Rua São Francisco Xavier, 524, 20550-013 RJ (Brazil)

2013-06-25

Highlights: ► Anisotropic magnetocaloric effect in in Tb{sub 0.4}Gd{sub 0.6}Al{sub 2}. ► Prediction of barocaloric effect in Tb{sub 0.4}Gd{sub 0.6}Al{sub 2}. ►An optimal hybrid magnetocaloric material using Tb{sub y}Gd{sub (1-y)}Al{sub 2} compounds. -- Abstract: We report the calculations on the magnetocaloric and barocaloric effects in ferromagnetic series Tb{sub y}Gd{sub (1−y)}Al{sub 2}. Our model includes the crystalline electrical field interaction, exchange interactions among Tb–Tb, Gd–Gd and Tb–Gd magnetic ions and the Zeeman effect for an anisotropic system. The lattice and electronic entropies were included in adiabatic processes. The magnetocaloric effect calculated for magnetic field changes along the easy magnetic direction 〈1 1 1〉 is in good agreement with the experimental data. Calculation along the hard magnetization direction 〈0 0 1〉 predicts anomalous magnetocaloric effect, which was ascribed to the spin reorientation processes. From the available experimental data of Curie temperature dependence on pressure, the exchange model parameters were scaled and the barocaloric effect was calculated.

Electronic band structure calculations for GaxIn1−xASyP1−y alloys lattice matched to InP

International Nuclear Information System (INIS)

Bechiri, A; Benmakhlouf, F; Allouache, H; Bacha, S; Bouarissa, N

2012-01-01

A pseudopotential formalism coupled with the virtual crystal approximation are applied to study the effect of compositional disorder upon electronic band structure of cubic Ga x In 1−x As y P 1−y quarternary alloys lattice matched to InP. The effects of compositional variations are properly included in the calculations. Very good agreement is obtained between the calculated values and the available experimental data for the lattice–matched alloy to InP. The absorption at the fundamental optical gaps is found to be direct within a whole range of the y composition whatever the lattice-matching to the substrate of interest. The alloy system Ga x In 1−x As y P 1−y lattice matched to InP is suggested to be suitable for an efficient light emitting device (ELED) material.

Nitrogen lattice location in MOVPE grown Ga1-xInxNyAs1-y films using ion beam channeling

International Nuclear Information System (INIS)

Nebiki, Takuya; Narusawa, Tadashi; Kumagai, Akiko; Doi, Hideyuki; Saito, Tadashi; Takagishi, Shigenori

2006-01-01

We have investigated the nitrogen lattice location in MOVPE grown Ga 1-x In x N y As 1-y with x=0.07 and y=0.025 by means of ion beam channeling technique. In this system, the lattice constant of the Ga 1-x In x N y As 1-y film is equal to GaAs lattice. Therefore, we can grow apparently no strain, high quality and very thick GaInNAs film on GaAs substrate. The quality of the films as well as the lattice location of In and N were characterized by channeling Rutherford backscattering spectrometry and nuclear reaction analysis using 3.95 MeV He 2+ beam. The fraction of substitutional nitrogen in the film was measured using the 14 N(α,p) 17 O endothermic nuclear reaction. Our results indicate that more than 90% of In and N atoms are located the substitutional site, however, N atoms are slightly displaced by ∼0.2 A from the lattice site. We suggest that the GaInNAs film has a local strain or point defects around the N atoms. (author)

Ba{sub y}Sr{sub 1−y}TiO{sub 3} buffer layers for strain tuning of infinite-layer Sr{sub 1−x}La{sub x}CuO{sub 2} thin films

Energy Technology Data Exchange (ETDEWEB)

Sakuma, Keita, E-mail: sakuma.keita@d.mbox.nagoya-u.ac.jp; Ito, Masataka; He, Yilun; Hajiri, Tetsuya; Ueda, Kenji; Asano, Hidefumi

2016-08-01

We report on the precise tuning of lattice strain in an infinite-layer electron-doped high temperature superconductor Sr{sub 1−x}La{sub x}CuO{sub 2} (SLCO; a{sub SLCO} = 0.3949 nm for x = 0.1), which is a perovskite-related oxide, using perovskite BaTiO{sub 3}–SrTiO{sub 3} (BSTO; Ba{sub y}Sr{sub 1−y}TiO{sub 3}) buffer layers. The BSTO buffer layers formed on (001) (La{sub 0.18}Sr{sub 0.82})(Al{sub 0.59}Ta{sub 0.41})O{sub 3} substrates by magnetron sputtering were fully relaxed with high crystalline quality due to high oxygen partial pressure deposition and post annealing at 950 °C. The lattice constants of the BSTO buffer layers could be controlled in the range of 0.3926–0.3973 nm by changing the Ba content (y = 0.2–0.7). These BSTO buffer layers allow coherent growth of SLCO thin films, and a clear dependence of the superconducting transition temperature on the lattice strain was observed. The fabrication of these BSTO/superconductor heterostructures may provide novel devices composed of functional perovskite thin films, in addition to a general approach for the precise control of lattice strain in functional perovskite thin films. - Highlights: • Ba{sub y}Sr{sub 1−y}TiO{sub 3} buffer layers were developed for the strain tuning of perovskite-related oxides. • Strain effect in Sr{sub 1−x}La{sub x}CuO{sub 2} was investigated by using Ba{sub y}Sr{sub 1−y}TiO{sub 3} buffer layers. • Ba{sub y}Sr{sub 1−y}TiO{sub 3} buffer layers can be used to tune the strain in other perovskite oxides.

NMR study of Y2(Co1-xFex)14B compounds

International Nuclear Information System (INIS)

Maruyama, F.; Ichinose, K.; Nagai, H.; Adachi, K.; Misawa, M.; Tsujimura, A.

1992-01-01

59 Co and 89 Y NMR of Y 2 (Co 1-x Fe x ) 14 B compounds has been measured at 4.2 K. The line positions shift rapidly to higher frequency for x≤0.3 and are almost constant for 0.3 1 and 8j 2 sites give a large contribution to the anisotropy of the 3d sublattice. (orig.)

Extracellular enzymatic activities and physiological profiles of yeasts colonizing fruit trees.

Science.gov (United States)

Molnárová, Jana; Vadkertiová, Renáta; Stratilová, Eva

2014-07-01

Yeasts form a significant and diverse part of the phyllosphere microbiota. Some yeasts that inhabit plants have been found to exhibit extracellular enzymatic activities. The aim of the present study was to investigate the ability of yeasts isolated from leaves, fruits, and blossoms of fruit trees cultivated in Southwest Slovakia to produce extracellular enzymes, and to discover whether the yeasts originating from these plant organs differ from each other in their physiological properties. In total, 92 strains belonging to 29 different species were tested for: extracellular protease, β-glucosidase, lipase, and polygalacturonase activities; fermentation abilities; the assimilation of xylose, saccharose and alcohols (methanol, ethanol, glycerol); and for growth in a medium with 33% glucose. The black yeast Aureobasidium pullulans showed the largest spectrum of activities of all the species tested. Almost 70% of the strains tested demonstrated some enzymatic activity, and more than 90% utilized one of the carbon compounds tested. Intraspecies variations were found for the species of the genera Cryptococcus and Pseudozyma. Interspecies differences of strains exhibiting some enzymatic activities and utilizing alcohols were also noted. The largest proportion of the yeasts exhibited β-glucosidase activity and assimilated alcohols independently of their origin. The highest number of strains positive for all activities tested was found among the yeasts associated with leaves. Yeasts isolated from blossoms assimilated saccharose and D-xylose the most frequently of all the yeasts tested. The majority of the fruit-inhabiting yeasts grew in the medium with higher osmotic pressure. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Characterization of a monoclonal antibody (P40) against the 68 kD major allergen of Penicillium notatum.

Science.gov (United States)

Shen, H D; Choo, K B; Chen, J H; Lin, W L; Chang, Z N; Han, S H

1992-04-01

A monoclonal antibody (MoAb P40) against the 68 kD major allergen of Penicillium notatum (P. notatum) was obtained by immunizing the mouse with a crude extract of P. notatum. Analysed by two-dimensional gel electrophoresis and immunoblotting, P40 reacted with two different isoforms of the 68 kD component of P. notatum with pIs of 5.4 and 5.5. In addition to P. notatum, P40 showed positive ELISA activity to Aspergillus fumigatus (A. fumigatus) but not to components of six other fungi including Alternaria porri, Cladosporium cladosporoides, Aureobasidium pullulans, Fusarium solani, Rhizopus arrhizus and Candida albicans. Analysed by ELISA, MoAb P40 also showed positive activity to two (P. frequentans and P. roseopurpureum) of the 10 other Penicillium species and two (A. terreus and A. flavus) of the four other Aspergillus species tested. SDS-PAGE and immunoblotting studies demonstrated P40 positive reactivity to components with MW of about 67 kD in all these Penicillium and Aspergillus species with positive ELISA activity to P40. Furthermore, immunoblotting activity of MoAb P40 to the 67 kD component of A. niger was also observed. The epitope of the 68 kD allergen of P. notatum recognized by MoAb P40 was resistant to treatment of periodate oxidation with concentration of NaIO4 up to 20 mM. This MoAb may thus be useful in the characterization and purification of the 68 kD allergen from crude extracts, and in the molecular cloning of allergen genes.

Yeast Identification During Fermentation of Turkish Gemlik Olives.

Science.gov (United States)

Mujdeci, Gamze; Arévalo-Villena, María; Ozbas, Z Yesim; Briones Pérez, Ana

2018-05-01

Naturally fermented black table olives of the Gemlik variety are one of the most consumed fermented products in Turkey. The objective of this work was to identify yeast strains isolated during their natural fermentation by using Restriction Fragments Lengths Polymorphism-Polimerase Chain Reaction (RFLP-PCR) and DNA sequencing methods. The study also focused on determining the effect of regional differences on yeast microflora of naturally fermented Gemlik olives. A total of 47 yeast strains belonging to 12 different species which had been previously isolated from the natural brine of Akhisar and Iznik-Gemlik cv. olives were characterized by molecular methods. Forty-two of the tested strains could be identified by RFLP-PCR to species level. These yeast species were determined as Candida mycetangi, Candida hellenica, Candida membranaefaciens, Candida famata, Candida pelliculosa, Saccharomyces cerevisiae, and Zygosaccharomyces mrakii. Five strains were identified by DNA sequencing. These strains belonged to three different species: Aureobasidium pullulans, Kloeckera apiculate, and Cryptococcus saitoi. The most frequent species were C. famata and C. pelliculosa in both regions. This work studies the yeasts from Turkish table olives which could prove to be of importance to the food industry in that area. On the other hand, it compares identification by molecular and classical biochemical methods and offers an idea about the differences between the ecosystems of Gemlik olives in the Akhisar (AO) and Iznik (IO) regions. The study could be useful in characterizing a very important product and, in this way, could help to promote its marketing. © 2018 Institute of Food Technologists®.

Environmental Metabarcoding Reveals Contrasting Belowground and Aboveground Fungal Communities from Poplar at a Hg Phytomanagement Site.

Science.gov (United States)

Durand, Alexis; Maillard, François; Foulon, Julie; Gweon, Hyun S; Valot, Benoit; Chalot, Michel

2017-11-01

Characterization of microbial communities in stressful conditions at a field level is rather scarce, especially when considering fungal communities from aboveground habitats. We aimed at characterizing fungal communities from different poplar habitats at a Hg-contaminated phytomanagement site by using Illumina-based sequencing, network analysis approach, and direct isolation of Hg-resistant fungal strains. The highest diversity estimated by the Shannon index was found for soil communities, which was negatively affected by soil Hg concentration. Among the significant correlations between soil operational taxonomic units (OTUs) in the co-occurrence network, 80% were negatively correlated revealing dominance of a pattern of mutual exclusion. The fungal communities associated with Populus roots mostly consisted of OTUs from the symbiotic guild, such as members of the Thelephoraceae, thus explaining the lowest diversity found for root communities. Additionally, root communities showed the highest network connectivity index, while rarely detected OTUs from the Glomeromycetes may have a central role in the root network. Unexpectedly high richness and diversity were found for aboveground habitats, compared to the root habitat. The aboveground habitats were dominated by yeasts from the Lalaria, Davidiella, and Bensingtonia genera, not detected in belowground habitats. Leaf and stem habitats were characterized by few dominant OTUs such as those from the Dothideomycete class producing mutual exclusion with other OTUs. Aureobasidium pullulans, one of the dominating OTUs, was further isolated from the leaf habitat, in addition to Nakazawaea populi species, which were found to be Hg resistant. Altogether, these findings will provide an improved point of reference for microbial research on inoculation-based programs of tailings dumps.

Metabarcoding Analysis of Fungal Diversity in the Phyllosphere and Carposphere of Olive (Olea europaea).

Science.gov (United States)

Abdelfattah, Ahmed; Li Destri Nicosia, Maria Giulia; Cacciola, Santa Olga; Droby, Samir; Schena, Leonardo

2015-01-01

The fungal diversity associated with leaves, flowers and fruits of olive (Olea europaea) was investigated in different phenological stages (May, June, October and December) using an implemented metabarcoding approach. It consisted of the 454 pyrosequencing of the fungal ITS2 region and the subsequent phylogenetic analysis of relevant genera along with validated reference sequences. Most sequences were identified up to the species level or were associated with a restricted number of related taxa enabling supported speculations regarding their biological role. Analyses revealed a rich fungal community with 195 different OTUs. Ascomycota was the dominating phyla representing 93.6% of the total number of detected sequences followed by unidentified fungi (3.6%) and Basidiomycota (2.8%). A higher level of diversity was revealed for leaves compared to flowers and fruits. Among plant pathogens the genus Colletotrichum represented by three species (C. godetiae syn. C. clavatum, C. acutatum s.s and C. karstii) was the most abundant on ripe fruits but it was also detected in other organs. Pseudocercospora cladosporioides was detected with a high frequency in all leaf samples and to a less extent in ripe fruits. A much lower relative frequency was revealed for Spilocaea oleagina and for other putative pathogens including Fusarium spp., Neofusicoccum spp., and Alternaria spp. Among non-pathogen taxa, Aureobasidium pullulans, the species complex of Cladosporium cladosporioides and Devriesia spp. were the most represented. This study highlights the existence of a complex fungal consortium including both phytopathogenic and potentially antagonistic microorganisms that can have a significant impact on olive productions.

Y-12 Groundwater Protection Program Groundwater Monitoring Data Compendium, Revision 1

Energy Technology Data Exchange (ETDEWEB)

None

2006-12-01

This document is a compendium of water quality and hydrologic characterization data obtained through December 2005 from the network of groundwater monitoring wells and surface water sampling stations (including springs and building sumps) at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) in Oak Ridge, Tennessee that have been sampled since January 2003. The primary objectives of this document, hereafter referenced as the Y-12 Groundwater Protection Program (GWPP) Compendium, are to: (1) Serve as a single-source reference for monitoring data that meet the requirements of the Y-12 GWPP, as defined in the Y-12 GWPP Management Plan (BWXT Y-12 L.L.C. [BWXT] 2004); (2) Maintain a detailed analysis and evaluation of the monitoring data for each applicable well, spring, and surface water sampling station, with a focus on results for the primary inorganic, organic, and radiological contaminants in groundwater and surface water at Y-12; and (3) Ensure retention of ''institutional knowledge'' obtained over the long-term (>20-year) history of groundwater and surface water monitoring at Y-12 and the related sources of groundwater and surface water contamination. To achieve these goals, the Y-12 GWPP Compendium brings together salient hydrologic, geologic, geochemical, water-quality, and environmental compliance information that is otherwise disseminated throughout numerous technical documents and reports prepared in support of completed and ongoing environmental contamination assessment, remediation, and monitoring activities performed at Y-12. The following subsections provide background information regarding the overall scope and format of the Y-12 GWPP Compendium and the planned approach for distribution and revision (i.e., administration) of this ''living'' document.

Effect of layer composition on band spectrum of CdxHg1-xTe - CdyHg1-yTe-type superlattices

International Nuclear Information System (INIS)

Gerchikov, L.G.; Subashiev, A.V.; Salman Dalla

1993-01-01

Evolution of energy spectrum of Cd x Hg 1-x Te -Cd y Hg 1-y Te superlattices at variation of layer composition is considered. Transition from 3 type superlattice to 1 type superlattice occurring for y=0.16 is studied comprehensively. In this case, dependence of the width of superlattice forbidden zone on layer thickness is shown to become more smooth, than in CdTe - HgTe superlattice and it gives more possibilities to use such superlattices for making IR phototransistors. 10 refs., 4 figs

Phase formation in the (1-y)BiFeO{sub 3}-yBiScO{sub 3} system under ambient and high pressure

Energy Technology Data Exchange (ETDEWEB)

Salak, A.N., E-mail: salak@ua.pt [Department of Materials and Ceramic Engineering and CICECO – Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro (Portugal); Khalyavin, D.D., E-mail: dmitry.khalyavin@stfc.ac.uk [ISIS Facility, Rutherford Appleton Laboratory, Chilton, OX11 0QX Didcot (United Kingdom); Pushkarev, A.V.; Radyush, Yu.V.; Olekhnovich, N.M. [Scientific-Practical Materials Research Centre of NAS of Belarus, P. Brovka Street, 19, 220072 Minsk (Belarus); Shilin, A.D.; Rubanik, V.V. [Institute of Technical Acoustics of NAS of Belarus, Lyudnikov Avenue, 13, 210023 Vitebsk (Belarus)

2017-03-15

Formation and thermal stability of perovskite phases in the BiFe{sub 1-y}Sc{sub y}O{sub 3} system (0≤y≤0.70) were studied. When the iron-to-scandium substitution rate does not exceed about 15 at%, the single-phase perovskite ceramics with the rhombohedral R3c symmetry (as that of the parent compound, BiFeO{sub 3}) can be prepared from the stoichiometric mixture of the respective oxides at ambient pressure. Thermal treatment of the oxide mixtures with a higher content of scandium results in formation of two main phases, namely a BiFeO{sub 3}-like R3c phase and a cubic (I23) sillenite-type phase based on γ-Bi{sub 2}O{sub 3}. Single-phase perovskite ceramics of the BiFe{sub 1-y}Sc{sub y}O{sub 3} composition were synthesized under high pressure from the thermally treated oxide mixtures. When y is between 0 and 0.25 the high-pressure prepared phase is the rhombohedral R3c with the √2a{sub p}×√2a{sub p}×2√3a{sub p} superstructure (a{sub p} ~ 4 Å is the pseudocubic perovskite unit-cell parameter). The orthorhombic Pnma phase (√2a{sub p}×4a{sub p}×2√2a{sub p}) was obtained in the range of 0.30≤y≤0.60, while the monoclinic C2/c phase (√6a{sub p}×√2a{sub p}×√6a{sub p}) is formed when y=0.70. The normalized unit-cell volume drops at the crossover from the rhombohedral to the orthorhombic composition range. The perovskite BiFe{sub 1-y}Sc{sub y}O{sub 3} phases prepared under high pressure are metastable regardless of their symmetry. At ambient pressure, the phases with the compositions in the ranges of 0.20≤y≤0.25, 0.30≤y<0.50 and 0.50≤y≤0.70 start to decompose above 970, 920 and 870 K, respectively. - Graphical abstract: Formation of perovskite phases in the BiFe{sub 1-y}Sc{sub y}O{sub 3} system when y≥0.15 requires application of pressure of several GPa. The phases formed under high pressure: R3c (0.20≤y≤0.25), Pnma (0.30≤y≤0.60) and C2/c (y≥0.70) are metastable. - Highlights: • Maximal Fe-to-Sc substitution rate in Bi

Y-chromosome-specific microsatellite mutation rates re-examined using a minisatellite, MSY1.

Science.gov (United States)

Jobling, M A; Heyer, E; Dieltjes, P; de Knijff, P

1999-10-01

Polymorphic Y-chromosome-specific microsatellites are becoming increasingly used in evolutionary and forensic studies and, in particular, in dating the origins of Y-chromosomal lineages. Previously, haplotyping of Y chromosomes from males belonging to a set of deep-rooting pedigrees was used to estimate a conservative average Y-chromosomal microsatellite mutation rate of 2.1 x 10(-3)per locus per generation. A number of males showed multiple differences in haplotypes compared with other males within their pedigrees, and these were excluded from the calculation of this estimate, on the grounds that non-paternity was a more probable explanation than multiple mutation within a lineage. Here we reanalyse the pedigrees using an independent highly polymorphic system, the Y-specific minisatellite, MSY1. This supports the hypothesis of non-paternity where more than one microsatellite difference was observed, provides further support for the previously deduced microsatellite mutation rate and throws light on the mutation dynamics of MSY1 itself, suggesting that single-step changes are not the only mode of mutation.

The thermal expansion coefficient of Ga/sub x/In/sub 1-x/As/sub y/P/sub 1-y/ epitaxial layers grown on InP substrate

International Nuclear Information System (INIS)

Pietsch, U.; Marlow, D.

1986-01-01

The amount of the measured room temperature thermal expansion coefficient of tetragonal strained layers grown lattice matched on the InP substrate used is about 30% greater the expected one for a cubic 'relaxed' material. This issue has to be taken into account for the determination of the composition of the quarternary Ga/sub x/In/sub 1-x/As/sub y/P/sub 1-y/ layers from both X-ray and photoluminescence data as well as for the estimation of the thermally created stress field of optoelectronic devices. (author)

Exciton-related nonlinear optical response and photoluminescence in dilute nitrogen In{sub x}Ga{sub 1−x}N{sub y}As{sub 1−y}/GaAs cylindrically shaped quantum dots

Energy Technology Data Exchange (ETDEWEB)

Duque, C.M.; Morales, A.L. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia); Mora-Ramos, M.E. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia); Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca, Morelos (Mexico); Duque, C.A. [Grupo de Materia Condensada-UdeA, Instituto de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín (Colombia)

2014-10-15

An investigation of the effects of the dilute nitrogen contents in the exciton states of cylindrical In{sub x}Ga{sub 1−x}N{sub y}As{sub 1−y}/GaAs quantum dots is presented. The exciton states in the system are obtained within the effective mass theory and the band anti-crossing model. Exciton-related nonlinear optical absorption and refractive index change, as well as excitonic photoluminescence are studied with the help of the calculated exciton states. - Highlights: • Theoretical study of excitons in cylindrical In{sub x}Ga{sub 1−x}N{sub y}As{sub 1−y}/GaAs quantum dots. • Calculations of binding energy for different configurations of electron-hole pairs. • Nonlinear optical absorption and refractive index changes. • Dependence of photoluminescence energy transitions with several inputs.

Electrical resistivity and thermopower of Y1-xPrxCo2 Compounds

International Nuclear Information System (INIS)

Uchima, K; Takaesu, Y; Teruya, A; Akamine, H; Kakihana, M; Tomori, K; Uejo, T; Nakamura, A; Hedo, M; Nakama, T; Yagasaki, K; Burkov, A T

2015-01-01

Electrical resistivity ρ and thermopower S of the pseudo-binary compounds of Y 1-x Pr x Co 2 have been measured in the temperature range between 2 and 300 K under magnetic fields up to 10 T, together with the pressure measurements of ρ and S in Y 0.4 Pr 0.6 Co 2 . The Curie temperature decreases with decreasing x, and vanishes at the critical composition x c ≈ 0.4, where the residual resistivity attains a maximum value. The Curie temperature and the residual resistivity of Y 0.4 Pr 0.6 Co 2 show the same pressure dependence as those of the heavy-rare-earth based compounds. These behaviors of ρ and S indicate the inhomogeneous distribution of the Co 3d magnetization. The magnetoresistance of the light-rare earth Y 1-x Pr x Co 2 system is negative in the whole range of x, except for x = 0 and 1, which is a characteristic behavior related with magnetic state and magnitude of the effective field acting on the Co 3d subsystem

Identification of Y (4008), Y (4140), Y (4260), and Y (4360) as Tetraquark States

International Nuclear Information System (INIS)

Zhou Ping; Deng Cheng-Rong; Ping Jia-Lun

2015-01-01

Within the framework of a color flux-tube model with a four-body confinement potential, the tetraquark states [cq][c¯q¯] (q = u or d) with I J"P"C = 01"− "− are systematically investigated. The numerical results indicate that states Y (4008), Y (4140), Y (4260), and Y (4360) can be uniformly described as tetraquark states [cq][c¯q¯] with n"2"S"+"1 L_J of 1"1 P_1, 1"5 P_1, 2"5 P_1 and 1"5F_1, respectively, in the color flux-tube model. They are compact three-dimensional spatial configurations similar to a rugby ball, higher orbital angular momentum L, more prolate. The four-body confinement interaction based on a color flux-tube picture should be responsible for the formation of those compact tetraquark states. (paper)

Genotipificación de polimorfismos moleculares en los genes CYP2E1, GSTM1 y GSTT1 para evaluar susceptibilidad a Cáncer gastrointestinal en una población paisa

Directory of Open Access Journals (Sweden)

DL. Zuluaga

2001-07-01

Full Text Available Entre los años 2001 y 2002 se recogieron 40 muestras de pacientes diagnosticados con cáncergastrointestinal en los departamentos de Antioquia y Caldas, a los cuales se les determinó elgenotipo molecular para los genes CYP2E1, GSTM1 y GSTT1 en sangre y se les realizó una entre-vista para analizar su consumo de alcohol, cigarrillo y alimentos quemados y/o embutidos, ya queestudios previos en otras poblaciones han sugerido la asociación de algunos polimorfismos de estos genes (en combinación o no con factores ambientales, con una predisposición a la enfermedad. Por tanto, se comparó estadísticamente las frecuencias genotípicas con las de unapoblación de controles sanos apareada con los casos por edad y sexo, y se observó la suscep-tibilidad a cáncer gastrointestinal, mediante el análisis de asociación a polimorfismos en los genesque codifican para las enzimas CYP2E1, GSTM1 Y GSTT1 del metabolismo de xenobióticos.

Intermolecular Interactions between Eosin Y and Caffeine Using 1H-NMR Spectroscopy

Directory of Open Access Journals (Sweden)

Macduff O. Okuom

2013-01-01

Full Text Available DETECHIP has been used in testing analytes including caffeine, cocaine, and tetrahydrocannabinol (THC from marijuana, as well as date rape and club drugs such as flunitrazepam, gamma-hydroxybutyric acid (GHB, and methamphetamine. This study investigates the intermolecular interaction between DETECHIP sensor eosin Y (DC1 and the analyte (caffeine that is responsible for the fluorescence and color changes observed in the actual array. Using 1H-NMR, 1H-COSY, and 1H-DOSY NMR methods, a proton exchange from C-8 of caffeine to eosin Y is proposed.

Arrestin scaffolds NHERF1 to the P2Y12 receptor to regulate receptor internalization.

Science.gov (United States)

Nisar, Shaista P; Cunningham, Margaret; Saxena, Kunal; Pope, Robert J; Kelly, Eamonn; Mundell, Stuart J

2012-07-13

We have recently shown in a patient with mild bleeding that the PDZ-binding motif of the platelet G protein-coupled P2Y(12) receptor (P2Y(12)R) is required for effective receptor traffic in human platelets. In this study we show for the first time that the PDZ motif-binding protein NHERF1 exerts a major role in potentiating G protein-coupled receptor (GPCR) internalization. NHERF1 interacts with the C-tail of the P2Y(12)R and unlike many other GPCRs, NHERF1 interaction is required for effective P2Y(12)R internalization. In vitro and prior to agonist stimulation P2Y(12)R/NHERF1 interaction requires the intact PDZ binding motif of this receptor. Interestingly on receptor stimulation NHERF1 no longer interacts directly with the receptor but instead binds to the receptor via the endocytic scaffolding protein arrestin. These findings suggest a novel model by which arrestin can serve as an adaptor to promote NHERF1 interaction with a GPCR to facilitate effective NHERF1-dependent receptor internalization.

Structural and electronic properties of Ga{sub 1-x}In{sub x} As{sub 1-y}N{sub y} quaternary semiconductor alloy on GaAs substrate

Energy Technology Data Exchange (ETDEWEB)

Aslan, Metin, E-mail: maslan@sakarya.edu.tr [Sakarya University, Art, Science Faculty, Department of Physics, Esentepe Campus, 54187 Sakarya (Turkey); Yalc Latin-Small-Letter-Dotless-I n, Battal G.; Uestuendag, Mehmet [Sakarya University, Art, Science Faculty, Department of Physics, Esentepe Campus, 54187 Sakarya (Turkey)

2012-04-05

Highlights: Black-Right-Pointing-Pointer In this study we used DFT in the frame of LDA approach to determine electronic and structural properties of GaInAsN alloy. Black-Right-Pointing-Pointer We calculated lattice parameter and band gap energy of binary (GaAs, InAs, and GaN), ternary (GaInAs, GaAsN) and quaternary (GaInAsN) semiconductor alloys. Black-Right-Pointing-Pointer We formulated lattice parameter of GaInAsN respect to In and N composition. Black-Right-Pointing-Pointer We investigated different In and N composition of GaInAsN/GaAs heterostructure for various device applications. - Abstract: We have presented structural and electronic properties of binary (GaAs, GaN and InAs), ternary (Ga{sub 1-x}In{sub x}As and GaAs{sub 1-y}N{sub y}) and quaternary (Ga{sub 1-x}In{sub x}As{sub 1-y}N{sub y}) semiconductor alloys by using a first-principles pseudopotential technique. The structural and electronic properties of Zinc-Blende phase of these materials have been calculated by using the local density approximation (LDA) of the density-functional theory (DFT). To obtain the lattice parameter and band gap energy of the (GaInAsN) quaternary semiconductor alloy we separately calculated the lattice constant and band gap energies of ternary semiconductor alloys, namely GaAsN and GaInAs. The calculated lattice constant, bulk modulus and the direct band gaps for studied semiconductors showed great parallelism with the previous available theoretical and experimental studies.

Defect structure, electronic conductivity and expansion of properties of (La1−xSrx)sCo1−yNiyO3−δ

DEFF Research Database (Denmark)

Hjalmarsson, Per; Søgaard, Martin; Mogensen, Mogens Bjerg

2010-01-01

This study reports on oxygen nonstoichiometry, electronic conductivity and lattice expansion of three compositions as function of T and PO2 in the (La1−xSrx)sCo1−yNiyO3−δ (x=0.1, y=0.4; x=0.1, y=0.3; x=0.2, y=0.2) materials system. The nonstoichiometry data were successfully fitted using the itin......This study reports on oxygen nonstoichiometry, electronic conductivity and lattice expansion of three compositions as function of T and PO2 in the (La1−xSrx)sCo1−yNiyO3−δ (x=0.1, y=0.4; x=0.1, y=0.3; x=0.2, y=0.2) materials system. The nonstoichiometry data were successfully fitted using...... the itinerant electron model which indicates the existence of delocalized electronic states. This was also reflected in the high electronic conductivities, above 1000 S cm−1, measured for all three compositions. The electronic conductivity was shown to decrease linearly with the oxygen nonstoichiometry...... parameter, δ, supporting that the conductivity is dependent on p-type charge carriers. Comparing calculated p-type mobilities with data reported in literature on La1−xSrxCoO3 indicated that Ni-substitution into (La1−xSrx)sCoO3−δ increases the p-type mobility. The electronic conductivity was also found...

Y-27632 Increases Sensitivity of PANC-1 Cells to EGCG in Regulating Cell Proliferation and Migration.

Science.gov (United States)

Liu, Xing; Bi, Yongyi

2016-10-03

BACKGROUND The study aimed to investigate the inhibitory effect of (1R,4r)-4-((R)-1-aminoethyl)-N-(pyridin-4-yl) cyclohexanecarboxamide (Y-27632) and (-)-epigallocatechin-3-gallate (EGCG) on the proliferation and migration of PANC-1 cells. EGCG, found in green tea, has been previously shown to be one of the most abundant and powerful catechins in cancer prevention and treatment. Y-27632, a selective inhibitor of rho-associated protein kinase 1, is widely used in treating cardiovascular disease, inflammation, and cancer. MATERIAL AND METHODS PANC-1 cells, maintained in Dulbecco's Modified Eagle's Medium, were treated with dimethyl sulfoxide (control) as well as different concentrations (20, 40, 60, and 80 μg/mL) of EGCG for 48 h. In addition, PANC-1 cells were treated separately with 60 μg/mL EGCG, 20 μM Y-27632, and EGCG combined with Y-27632 (60 μg/mL EGCG + 20 μM Y-27632) for 48 h. The effect of EGCG and Y-27632 on the proliferation and migration of PANC-1 cells was evaluated using Cell Counting Kit-8 and transwell migration assays. The expression of peroxisome proliferator-activated receptor alpha (PPARα) and Caspase-3 mRNA was determined by Quantitative real-time polymerase chain reaction (RT-qPCR). RESULTS EGCG (20-80 μg/mL) inhibited cell viability in a dose-dependent manner. Y-27632 enhanced the sensitivity of PANC-1 cells to EGCG (by increasing the expression of PPARa and Caspase-3 mRNA) and suppressed cell proliferation. PANC-1 cell migration was inhibited by treatment with a combination of EGCG and Y-27632. CONCLUSIONS Y-27632 increases the sensitivity of PANC-1 cells to EGCG in regulating cell proliferation and migration, which is likely to be related to the expression of PPARa mRNA and Caspase-3 mRNA.

Crystallisation kinetics of amorphous Fe72.5-xCu1Nb4.5Si10+x+yB12-y alloy

International Nuclear Information System (INIS)

Miglierini, M.; Lipka, J.; Sitek, J.

1994-01-01

Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 and Fe 72.5-x Cu 1 Nb 4.5 Si 10+x+y B 12-y alloys are compared from the point of view of crystallisation behaviour and changes in the short-range order in the amorphous reminder. The increase in Nb to 4.5 at.% in the latter system slows down the formation of nanocrystals to approximately 40% even after 16 hours of anneal at 550 C for x = 0.5, y = 3. Segregation-induced changes in the short-range order are manifested via hyperfine field distributions corresponding to the amorphous reminder. (orig.)

Optical characterization in Pb(Zr{sub 1-x} Ti{sub x}){sub 1-y} Nb{sub y} O{sub 3} ferroelectric ceramic system

Energy Technology Data Exchange (ETDEWEB)

Durruthy-Rodriguez, M.D. [Instituto de Cibernetica, Matematica y Fisica, CITMA, Departamento de Fisica Aplicada, La Habana (Cuba); CINVESTAV-Unidad Queretaro, IPN, Santiago de Queretaro, Queretaro (Mexico); Costa-Marrero, J.; Hernandez-Garcia, M. [Instituto de Cibernetica, Matematica y Fisica, CITMA, Departamento de Fisica Aplicada, La Habana (Cuba); Calderon-Pinar, F. [Universidad de La Habana, Laboratorio de Magnetismo, Instituto de Ciencia y Tecnologia de Materiales, La Habana (Cuba); Malfatti, Celia [Universidade Federal do Rio Grande do Sul, Departamento de Metalurgia, Escola de Engenharia, Porto Alegre, RS (Brazil); Yanez-Limon, J.M. [CINVESTAV-Unidad Queretaro, IPN, Santiago de Queretaro, Queretaro (Mexico)

2011-05-15

In this work, visible photoluminescence was observed at room temperature in a sintered Pb(Zr{sub 1-x}Ti{sub x}){sub 1-y}Nb{sub y}O{sub 3} perovskite-type structure system, doped with Nb using the next excitation bands 325, 373 and 457 nm. The intensity and energy of such emissions have been studied by changing the Nb concentration (0<y<0.01) and the Ti content (x), with x=0.20,0.40,0.53,0.60 and 0.80, on both sides of the morphotropic phase boundary (MPB) zone. The principal bands become visible at energies of 1.73, 2.56 and 3.35 eV. The results reveal the role of the Nb{sup 5+} ion substitutions by Zr{sup 4+} or Ti{sup 4+} ions and the symmetry presented in the rhombohedral or tetragonal side of the MPB. Raman spectra which are similar for compositions: 20/80, 40/60 and 53/47 (tetragonal phases) show nine bands, centered around 137, 194, 269, 331, 434, 550, 612, 712 and 750 cm{sup -1}. The spectra for samples 60/40 and 80/20, rhombohedral phase, show significant differences, only six bands appear, centered around 124, 209, 234, 330, 549 and 682 cm{sup -1}. In addition, optical absorption spectroscopy, structural and micro-structural measurements were carried out by using Uv-vis spectroscopy, X-ray diffraction and scanning electron microscopy techniques, respectively. The experimental results of band gap energy, e.g., in our samples are in accordance with the findings by J. Baedi et al. in the calculations of band structure, energy gap and density of states for different phases of Pb(Zr{sub 1-x} Ti{sub x})O{sub 3} using density functional theory (DFT). (orig.)

Tratamiento del concepto de ser vivo y los reinos monera, protista y fungi en la atención a la diversidad de 1º ESO

OpenAIRE

Nepote Gorriz, Ainara

2012-01-01

Los contenidos que se tratan en este proyecto intentando diseñar unos contenidos y actividades conceptualmente transparentes para el alumnado, se dividen en 2 grandes apartados: primero se trata el concepto de ser vivo con 3 actividades diferentes, y luego los reinos monera, protista y fungi. Los objetivos generales que se establecen para este proyecto son los siguientes: 1. Acercar el concepto de ser vivo a alumnos y a alumnas de atención de la diversidad de 1º ESO ampliand...

Monte-Carlo investigation of in-plane electron transport in tensile strained Si and Si{_{1-y}}C{_y} (y {leq 0.03})

Science.gov (United States)

Dollfus, Ph.; Galdin, S.; Hesto, P.

1999-07-01

Electron transport properties in tensile strained Si-based materials are theoretically analyzed using Monte-Carlo calculation. We focus our interest on in-plane transport in Si and Si{1-y}Cy (yleq 0.03), grown respectively on Effect-Transistor application. In comparison with unstrained Si, the tensile strain effect is shown to be very attractive in Si: drift mobilities greater than 3000 cm^2/Vs are obtained at 300 K for a Ge fraction mole of 0.2 in the pseudo-substrate. In the Si{1-y}Cy/Si system, that does not need any pseudo-substrate, the beneficial strain effect on transport is counterbalanced by the alloy scattering whose influence on mobility is studied. If the alloy potential is greater than about 1 eV, the advantage of strain-induced reduction of effective mass is lost in terms of stationary transport performance at 300 K.

Waset Isolation Pilot Plant Annual Site Environmental Report for 2006

Energy Technology Data Exchange (ETDEWEB)

Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

2007-09-26

The purpose of the Waste Isolation Pilot Plant Annual Site Environmental Report for 2006 (ASER) is to provide information required by U.S. Department of Energy (DOE) Order 231.1A, Environment, Safety, and Health Reporting. Specifically, the ASER presents summary environmental data that: (a) Characterize site environmental management performance; (b) Summarize environmental occurrences and responses reported during the calendar year; (c) Confirm compliance with environmental standards and requirements; and (d) Highlight significant facility programs and efforts. The DOE Carlsbad Field Office (CBFO) and Washington TRU Solutions LLC (WTS) maintain and preserve the environmental resources at the WIPP site. DOE Order 231.1A; DOE Order 450.1, Environmental Protection Program; and DOE Order 5400.5, Radiation Protection of the Public and Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and the environment. This report was prepared in accordance with DOE Order 231.1A. This order requires that DOE facilities submit an ASER to the DOE Headquarters Office of the Assistant Secretary for Environment, Safety, and Health. The WIPP Hazardous Waste Facility Permit (HWFP) (No. NM4890139088-TSDF [treatment, storage, and disposal facility]) further requires that the ASER be provided to the New Mexico Environment Department (NMED).

Waset Isolation Pilot Plant Annual Site Environmental Report for 2006

International Nuclear Information System (INIS)

2007-01-01

The purpose of the Waste Isolation Pilot Plant Annual Site Environmental Report for 2006 (ASER) is to provide information required by U.S. Department of Energy (DOE) Order 231.1A, Environment, Safety, and Health Reporting. Specifically, the ASER presents summary environmental data that: (a) Characterize site environmental management performance; (b) Summarize environmental occurrences and responses reported during the calendar year; (c) Confirm compliance with environmental standards and requirements; and (d) Highlight significant facility programs and efforts. The DOE Carlsbad Field Office (CBFO) and Washington TRU Solutions LLC (WTS) maintain and preserve the environmental resources at the WIPP site. DOE Order 231.1A; DOE Order 450.1, Environmental Protection Program; and DOE Order 5400.5, Radiation Protection of the Public and Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and the environment. This report was prepared in accordance with DOE Order 231.1A. This order requires that DOE facilities submit an ASER to the DOE Headquarters Office of the Assistant Secretary for Environment, Safety, and Health. The WIPP Hazardous Waste Facility Permit (HWFP) (No. NM4890139088-TSDF [treatment, storage, and disposal facility]) further requires that the ASER be provided to the New Mexico Environment Department (NMED).

Artificial intelligence based modeling and optimization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production process by using Azohydromonas lata MTCC 2311 from cane molasses supplemented with volatile fatty acids: a genetic algorithm paradigm.

Science.gov (United States)

Zafar, Mohd; Kumar, Shashi; Kumar, Surendra; Dhiman, Amit K

2012-01-01

The present work describes the optimization of medium variables for the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] by Azohydromonas lata MTCC 2311 using cane molasses supplemented with propionic acid. Genetic algorithm (GA) has been used for the optimization of P(3HB-co-3HV) production through the simulation of artificial neural network (ANN) and response surface methodology (RSM). The predictions by ANN are better than those of RSM and in good agreement with experimental findings. The highest P(3HB-co-3HV) concentration and 3HV content have been reported as 7.35 g/l and 16.84 mol%, respectively by hybrid ANN-GA. Upon validation, 7.20 g/l and 16.30 mol% of P(3HB-co-3HV) concentration and 3HV content have been found in the shake flask, whereas 6.70 g/l and 16.35 mol%, have been observed in a 3 l bioreactor, respectively. The specific growth rate and P(3HB-co-3HV) accumulation rate of 0.29 per h and 0.16 g/lh determined with cane molasses are comparable to those observed on pure substrates. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nanostructuring and high thermoelectric efficiency in p-type Ag(Pb{sub 1-y}Sn{sub y}){sub m}SbTe{sub 2{sub +m}}

Energy Technology Data Exchange (ETDEWEB)

Androulakis, J; Hsu, K F; Pcionek, R; Kanatzidis, M G [Department of Chemistry, Michigan Sate University, East Lansing, MI 48824-1793 (United States); Kong, H; Uher, C [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); D' Angelo, J J; Downey, A; Hogan, T [Electrical and Computer Engineering Department, Michigan State University, East Lansing, MI 48824-1226 (United States)

2006-05-02

The p-type Ag(Pb{sub 1-y}Sn{sub y}){sub m}SbTe{sub 2{sub +m}} materials shown in the figure demonstrate promising thermoelectric properties that are controlled with the parameters y and m. They can reach a maximum figure of merit of {proportional_to} 1.45 at 630 K. This surpasses the figure of merit of the present state-of-the-art p-type materials such as TAGS (1.2) and PbTe (0.8) at comparable temperatures. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

Upper limit for the emission of monoenergetic photons in Y(1S)- and Y(2S)-meson decays

International Nuclear Information System (INIS)

Albrecht, H.; Binder, U.; Harder, G.; Lembke-Koppitz, I.; Philipp, A.; Schmidt-Parzefall, W.; Schroeder, H.; Schulz, H.D.; Wurth, R.; Drescher, H.; Graewe, B.; Matthiesen, U.; Scheck, H.; Spengler, J.; Wegener, D.; Edwards, K.W.; Kapitza, H.; Yun, J.C.; Frisken, W.R.; Fukunaga, C.; Goddard, M.; Gilkinson, D.J.; Gingrich, D.M.; Kim, P.C.H.; Kutschke, R.; MacFarlane, D.B.; McKenna, J.A.; Orr, R.S.; Padley, P.; Prentice, J.D.; Seywerd, H.C.J.; Stacey, B.J.; Yoon, T.S.; Ammar, R.; Coppage, D.; Davis, R.; Kanekal, S.; Kwak, N.; Kernel, G.; Plesko, M.; Childers, R.; Darden, C.W.; Gennow, H.

1985-08-01

We report the results of a search for monoenergetic photons in the decay of both the Y(1S)- and the Y(2S)-meson. Photons converted in the beam tube or the drift chamber inner wall, and photons detected with the barrel shower counters of the ARGUS detector, respectively, have been used in the analysis. No narrow peak is observed in the energy interval 0.5 GeV<=Esub(γ)<=4.0 GeV. (orig.)

Composición de leche de vacas Criollo, Guzerat y sus cruzas F1 y su relación con el peso al destete de las crías

Directory of Open Access Journals (Sweden)

Guillermo Martínez Velázquez

2010-01-01

Full Text Available Se utilizaron 619 registros productivos generados entre 2001 y 2003 por vacas Guzerat (G, Criollo (C, Guzerat x Criollo (GC y Criollo x Guzerat (CG. Las variables estudiadas fueron porcentaje de grasa (%G, proteína (%P, lactosa (%L y sólidos no grasos (%SNG contenidos en la leche y kilogramos de grasa (GP, proteína (PP, lactosa (LP y sólidos no grasos (SNGP producidos por lactancia. También se evaluaron peso al nacer (PN y peso al destete ajustado a 210 días de edad (PA210 y se estimaron efectos genéticos directos, maternos, de heterosis y la relación entre componentes de la leche y PA210. Para %G, %P, %L, %SNG, GP, PP, LP y SNGP los modelos incluyeron los efectos fijos de grupo genético de la vaca (GEN, número de parto (NP, año de parto (A, época de parto (E, días posparto (D e interacciones de dos factores (F. Para PN y PA210 los modelos incluyeron GEN, NP, A, E y F. Se estimaron correlaciones residuales entre componentes de la leche y PA210. Heterosis fue importante (P<0.05 para GP (5.07+1.9 kg, PP (4.97+1.5 kg, LP (7.04+2.1 kg, SNGP (13.48+3.8 kg, PN (-1.30+0.6 kg y PA210 (12.65+4.2 kg. Los efectos genéticos directos para LP, SNGP, PN y PA210 fueron favorables (P<0.05 a G en 11.08+3.7, 16.98+6.6, 3.80+1.1 y 37.60+7.6 kg. Se detectaron correlaciones importantes (P<0.05 de PA210 con GP (0.16, LP (0.21 y SNGP (0.19. Las correlaciones sugieren que la cantidad de componentes en la leche fue importante para determinar el peso al destete de los becerros.

Coexistence of 3d-ferromagnetism and superconductivity in (Li{sub 1-x}Fe{sub x}OH)(Fe{sub 1-y}Li{sub y}Se)

Energy Technology Data Exchange (ETDEWEB)

Brueckner, Felix; Sarkar, Rajib; Kamusella, Sirko; Klauss, Hans-Henning [Institut fuer Festkoerperphysik, Technische Universitaet Dresden (Germany); Luetkens, Hubertus [Paul-Scherrer-Institut, Villigen (Switzerland); Pachmayr, Ursula; Nitsche, Fabian; Johrendt, Dirk [Department Chemie, Ludwig-Maximilians-Universitaet Muenchen (Germany)

2015-07-01

In the family of iron-based superconductors, where the superconducting dome is usually separated from the magnetic phase, only few compounds show ferromagnetism arising in the superconducting state. The so far discovered examples show ferromagnetic ordering of Eu{sup 2+} ions. In this context, the presented ordering of iron orbitals in (Li{sub 1-x}Fe{sub x}OH)(Fe{sub 1-y}Li{sub y}Se) is unique. We performed a wealth of experimental methods to characterize the physics in this system, including dc resistivity and magnetization. With use of local probes (μSR,NMR,Moessbauer), we are able to describe the emergence of bulk ferromagnetism and superconductivity in a microscopic scale. Both phenomena can coexist, though they compete with each other, due to a spatial separation in the multilayer system.

Eficiencia de cultivo in vitro de Toxoplasma gondii en las líneas celulares THP1 y Vero

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Jorge Andrés Cuellar

2012-03-01

Full Text Available Introducción. El cultivo in vitro es un método importante para la obtención de Toxoplasma gondii confines de diagnóstico clínico o biotecnológico. Objetivo. Determinar el porcentaje de invasión y producción de T. gondii en las líneas celulares THP1y Vero. Materiales y métodos. Se determinó la curva de crecimiento para las células Vero y THP1 por conteoen hemocitómetro. Posteriormente, se identificó el porcentaje de invasión de T. gondii en células THP1y Vero por citometría de flujo, en diferentes proporciones célula/taquizoíto de 1/5, 1/20, 1/50. Por otrolado, se calculó el índice de rendimiento de T. gondii, cepa RH, y del aislamiento CIBM1 en célulasTHP1. Resultados. Las células Vero crecen más rápidamente que las células THP1, con un crecimientoexponencial en un periodo de siete días. El aislamiento CIBM1 infecta las células THP1 en las tresproporciones diferentes de 1/5,1/20 y 1/50 con porcentajes de invasión de 57,1 %, 15,5 % y 12,2 %, yen células Vero, de 25,3 %, 17,8 % y 8,8 %. La cepa RH de T. gondii mostró porcentajes de invasiónmás bajos, de 32,6 %, 14,8 % y 8,1 % en células THP1 y de 22,3 %, 14,1 % y 3,4 % en células Vero. Conclusiones. El aislamiento CIBM1 presentó mayor rendimiento con respecto a la cepa RH de T.gondii en células THP1, siendo estas células una buena línea para estudiar el proceso de invasión yprobar candidatos farmacológicos para reducir la infección por T. gondii.   doi: http://dx.doi.org/10.7705/biomedica.v32i3.485

BRCA1 and TP53 Gene-Mutations: Family Predisposition and Radioecological Risk of Developing Breast Cancer.

Science.gov (United States)

Apsalikov, Bakytbek; Manambaeva, Zukhra; Ospanov, Erlan; Massabayeva, Meruyert; Zhabagin, Kuantkan; Zhagiparova, Zhanar; Maximov, Vladymir; Voropaeva, Elena; Apsalikov, Kazbek; Belikhina, Tatiana; Abdrahmanov, Ramil; Cherepkova, Elena; Tanatarov, Sayat; Massadykov, Adilzhan; Urazalina, Naylia

2016-01-01

Frequencies of polymorphisms of genes BRCA1 and TP53 in breast cancer (BC) patients with a BC family history and radiation history were assessed and compared in the Semey region of Kazakhstan. The study included 60 women directly irradiated by the activities of the Semipalatinsk test site with a calculated effective equivalent dose of 500 mSv and their first generation descendants (group BC+Her+Exp); 65 women with family BC and absence of radiological history - the effective equivalent dose due to anthropogenic sources not exceeding 50 mSv (group BC+Her-Exp). The comparison group consisted of 65 women patients with breast cancer without family and radiological history (BC-Her-Exp). The control group comprised 60 women without breast cancer and without family and radiological history (nonBC). We carried out the genotyping of the polymorphisms c.2311T>C, c.4308T>C and 5382insC of the BRCA1 gene and rs1042522 of the TP53 gene. The frequency of the polymorphism c.2311T>C was significantly higher in patients of the group BC+Her+Exp than in healthy women, and of the polymorphism 5382insC in BC+Her+Exp compared to all other groups. The frequency of the rs1042522 polymorphism of TP53 was significantly higher in all groups of patients with breast cancer compared with the control group. Differences between groups of women with breast cancer were significant only in BC+Her+Exp vs. BC+Her-Exp. Combinations of polymorphisms of the genes BRCA1 and TP53 predominated in women with a family and radiological history.

X1X1X2X2/X1X2Y sex chromosome systems in the Neotropical Gymnotiformes electric fish of the genus Brachyhypopomus

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Adauto Lima Cardoso

2015-06-01

Full Text Available Several types of sex chromosome systems have been recorded among Gymnotiformes, including male and female heterogamety, simple and multiple sex chromosomes, and different mechanisms of origin and evolution. The X1X1X2X2/X1X2Y systems identified in three species of this order are considered homoplasic for the group. In the genus Brachyhypopomus, only B. gauderio presented this type of system. Herein we describe the karyotypes of Brachyhypopomus pinnicaudatus and B. n. sp. FLAV, which have an X1X1X2X2/X1X2Y sex chromosome system that evolved via fusion between an autosome and the Y chromosome. The morphology of the chromosomes and the meiotic pairing suggest that the sex chromosomes of B. gauderio and B. pinnicaudatus have a common origin, whereas in B . n. sp. FLAV the sex chromosome system evolved independently. However, we cannot discard the possibility of common origin followed by distinct processes of differentiation. The identification of two new karyotypes with an X1X1X2X2/X1X2Y sex chromosome system in Gymnotiformes makes it the most common among the karyotyped species of the group. Comparisons of these karyotypes and the evolutionary history of the taxa indicate independent origins for their sex chromosomes systems. The recurrent emergence of the X1X1X2X2/X1X2Y system may represent sex chromosomes turnover events in Gymnotiformes.

Influence of substitutional disorder on the electrical transport and the superconducting properties of Fe{sub 1+z}Te{sub 1−x−y}Se{sub x}S{sub y}

Energy Technology Data Exchange (ETDEWEB)

Rodríguez, M.G. [Laboratorio de Bajas Temperaturas, Departamento de Física, FCEyNUBA and IFIBA-CONICET, Buenos Aires (Argentina); Polla, G.; Ramos, C.P. [Gerencia de Investigación y Aplicaciones, CAC-CNEA, San Martín (Argentina); Acha, C., E-mail: acha@df.uba.ar [Laboratorio de Bajas Temperaturas, Departamento de Física, FCEyNUBA and IFIBA-CONICET, Buenos Aires (Argentina)

2015-11-15

We have carried out an investigation of the structural, magnetic, transport and superconducting properties of Fe{sub 1+z}Te{sub 1−x−y}Se{sub x}S{sub y} ceramic compounds, for z = 0 and some specific Se (0 ≤ x ≤ 0.5) and S (0 ≤ y ≤ 0.12) contents. The incorporation of Se and S to the FeTe structure produces a progressive reduction of the crystallographic parameters as well as different degrees of structural disorder associated with the differences of the ionic radius of the substituting cations. In the present study, we measure transport properties of this family of compounds and we show the direct influence of disorder in the normal and superconductor states. We notice that the structural disorder correlates with a variable range hopping conducting regime observed at temperatures T > 200 K. At lower temperatures, all the samples except the one with the highest degree of disorder show a crossover to a metallic-like regime, probably related to the transport of resilient-quasi-particles associated with the proximity of a Fermi liquid state at temperatures below the superconducting transition. Moreover, the superconducting properties are depressed only for that particular sample, in accordance to the condition that superconductivity is affected by disorder when the electronic localization length ξ{sub L} becomes smaller than the coherence length ξ{sub SC}. - Highlights: • New Fe(1 + z)Te(1−x−y)Se(x)S(y) ceramic samples were synthesized. • Structural, magnetic, transport and superconducting properties are presented. • Nonmagnetic disorder determines a VRH conduction regime near room temperature. • Superconductivity is affected by disorder.

Implementación física, lógica, seguridad y respaldos en Cloud de la red de voz IP y datos del Distrito Educativo Ambato 1

OpenAIRE

Masaquiza Pinto, William Danilo

2017-01-01

1. Introducción. --2. Planteamiento de la Propuesta de Trabajo. --3. Marco Teórico. --4. Metodología. --5. Resultados. --6. Conclusiones y Recomendaciones. --Apéndices. La presente investigación tiene como objetivo implementar la red de voz IP y datos del Distrito Educativo Ambato 1 de manera física y lógica con medidas de seguridad y respaldos en Cloud (nube) para garantizar resultados eficaces y eficientes en la sistematización de procesos, aprovechando las NTICs, enfocado en redes infor...

Superconducting transition temperature in the Y(1-x)M(x)Ba2Cu3O(y) system

Science.gov (United States)

Suzuki, Takeyuki; Yamazaki, Tsutomu; Sekine, Ryuuta; Koukitsu, Akinori; Seki, Hisashi

1989-04-01

Experimental results are presented for the inclusion of compositional additives, M, to the sintered high-temperature superconductor Y(1-x)M(x)Ba2Cu3O(y); M can be the oxides of Mg, Ce, Gd, Yb, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Zn, B, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi, and Te, as well as Li, Na, K, Ca, Sr, and La carbonates. Temperature dependence of the electrical resistance was measured down to about 80 K. Attention is given to the influence of ionic radius and the valence of the M species.

Environmental Performance Report 2013: Annual Site Environmental Report per the U.S. Department of Energy Order 231.1-1B (Management Publication)

Energy Technology Data Exchange (ETDEWEB)

Schlomberg, K.; Eickhoff, J.; Beatty, B.; Braus, G.; Durbin, L.; Fiehweg, R.; Ray, M.; Ryon, T.; Schmitz, E.

2014-08-01

The National Renewable Energy Laboratory's (NREL's) Environmental Performance Report provides a description of the laboratory's environmental management activities for 2013, including information on environmental and sustainability performance, environmental compliance activities and status, and environmental protection programs, highlights, and successes. The purpose of this report is to ensure that U.S. Department of Energy (DOE) and the public receive timely, accurate information about events that have affected or could adversely affect the health, safety, and security of the public or workers; the environment; or the operations of DOE facilities. This report meets the requirements of the Annual Site Environmental Report and is prepared in accordance with the DOE Order 231.1B, Environment, Safety and Health Reporting.

Synthesis and characterization of (Lu{sub 1−x−y}Y{sub x}Ce{sub y}){sub 2}SiO{sub 5} luminescent powders with fast decay time

Energy Technology Data Exchange (ETDEWEB)

Aburto-Crespo, M. [Programa de Posgrado en Física de Materiales CICESE-UNAM, Km. 107 Carretera Tij-Ens, Ensenada, B. C. 22860, México (Mexico); Hirata, G.A., E-mail: hirata@cnyn.unam.mx [Centro de Nanociencias y Nanotecnología-Universidad Nacional Autónoma de México, Km. 107 Carretera Tijuana-Ensenada, Ensenada, B. C. 22860, México (Mexico); McKittrick, J. [University of California at San Diego, La Jolla, CA 92093-0411 (United States)

2013-04-15

The structural and luminescent properties of blue-emitting (Lu{sub 1−x−y}Y{sub x}Ce{sub y}){sub 2}SiO{sub 5} (0.1≤x≤0.4, y=0.05, 0.005) phosphors prepared by combustion synthesis and post-annealed at 1200 °C for different annealing times are reported. X-ray diffraction analysis revealed the formation of a (Lu,Y){sub 2}SiO{sub 5} solid solution as a majority phase with small traces of a residual phase that was identified as Lu{sub 2}SiO{sub 7}. Under long-UV excitation, the powders yield a very bright blue-emission consisting of two bands with maximum emissions located at λ=405 nm and λ=440 nm, both corresponding to the Ce{sup 3+} allowed transitions {sup 2}D{sub 3/2}→{sup 2}F{sub 5/2} and {sup 2}D{sub 5/2}→{sup 2}F{sub 7/2}, respectively. Moreover, luminescence decay times of 38–45 ns were measured, which depend on the composition, making these powders excellent candidates for application as scintillators in medical imaging. -- Highlights: ► A facile technique to fabricate (Lu,Y)-oxyorthosilicate nanophosphors is presented. ► The structural and excellent luminescent properties including excitation, emission and short decay times are reported. ► The Ce-doped oxyorthosilicates nanophosphors present a fast decay time of the order of 38–45 ns.

Architectural Processes and Physicochemical Properties of CoO/ZnO and Zn 1− x Co x O/Co 1− y Zn y O Nanocomposites

KAUST Repository

Yao, Ke Xin; Zeng, Hua Chun

2009-01-01

complex nanocomposite materials, especially for interdoped metal oxides. As an example, our as-prepared binary oxide composites Zn1-xCoxO/Co 1-yZnyO have shown good catalytic activity for oxidation of carbon monoxide at relatively low reaction temperatures

Dual mechanism of chromatin remodeling in the common shrew sex trivalent (XY 1Y 2

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Sergey N. Matveevsky

2017-11-01

Full Text Available Here we focus on the XY1Y2 condition in male common shrew Sorex araneus Linnaeus, 1758, applying electron microscopy and immunocytochemistry for a comprehensive analysis of structure, synapsis and behaviour of the sex trivalent in pachytene spermatocytes. The pachytene sex trivalent consists of three distinct parts: short and long synaptic SC fragments (between the X and Y1 and between the X and Y2, respectively and a long asynaptic region of the X in-between. Chromatin inactivation was revealed in the XY1 synaptic region, the asynaptic region of the X and a very small asynaptic part of the Y2. This inactive part of the sex trivalent, that we named the ‘head’, forms a typical sex body and is located at the periphery of the meiotic nucleus at mid pachytene. The second part or ‘tail’, a long region of synapsis between the X and Y2 chromosomes, is directed from the periphery into the nucleus. Based on the distribution patterns of four proteins involved in chromatin inactivation, we propose a model of meiotic silencing in shrew sex chromosomes. Thus, we conclude that pachytene sex chromosomes are structurally and functionally two different chromatin domains with specific nuclear topology: the peripheral inactivated ‘true’ sex chromosome regions (part of the X and the Y1 and more centrally located transcriptionally active autosomal segments (part of the X and the Y2.

Magnetic susceptibilities of Ca/sub y/U/sub 1-y/O/sub 2+x/ solid solutions

International Nuclear Information System (INIS)

Hinatsu, Y.; Fujino, T.

1988-01-01

Magnetic susceptibilities of Ca/sub y/U/sub 1-y/O/sub 2+x/ solid solutions with fluorite structure were measured from 4.2 K to room temperature. An antiferromagnetic transition was observed for all the solid solutions examined in this study (y ≤ 0.33). The Neel temperature of the oxygen-hypostoichiometric solid solutions (x 2 solid solutions, but different from that of (U,Th)O 2 solid solutions. The effective magnetic moment decreased with increasing calcium concentration, which indicates the oxidation of uranium in the solid solutions. From the analysis of the magnetic susceptibility data, it was found that the oxidation state of uranium was either tetravalent or pentavalent. The Neel temperature of the hyperstoichiometric solid solutions (x > 0) did not change appreciably with calcium concentrations. From the comparison of the magnetic susceptibility data of the hypostoichiometric solid solutions with those of the hyperstoichiometric solid solutions, the effect of oxygen vacancies is more significant than that of interstitial oxygens on the decrease of magnetic interactions between uranium ions

Enhancement of the response to purinergic agonists in P2Y1 transfected 1321N1 cells by antagonists suramin and PPADS.

Science.gov (United States)

Brown, C A; Charlton, S J; Boarder, M R

1997-03-01

1. We have previously shown that both suramin and pyridoxal-phosphate-6-azophenyl-2',4' disulphonic acid (PPADS) act as antagonists at transfected P2Y1 receptors. Here we show that under certain experimental conditions these two P2 antagonists can enhance the response to agonists acting at these receptors. 2. The expression of either P2Y1 or P2Y2 receptors in 1321N1 human astrocytoma cells results, on a change of medium, in an elevation of basal (no added agonist) accumulation of [3H]-inositol(poly)phosphates([3H]-InsPx) compared to cells not expressing these receptors. This elevation is much greater in P2Y1 transfectants than in P2Y, transfectants. 3. Both PPADS and suramin reduced this basal level of [3H]-InsPx accumulation in the P2Y1 expressing cells. 4. When a protocol was used which required changing the culture medium, antagonists were added at a concentration which reduced the basal accumulation by about 50%, there was a significant stimulation in response to increasing concentrations of 2-methylthioadenosine 5'-triphosphate (2MeSATP), in the absence of antagonists there was no significant effect of the agonist. 5. However, when 2MeSATP was added in the absence of a change of medium and with no antagonist present, there was a several fold increase in [3H]-InsPx accumulation. These results show that a release of endogenous agonist activity (possibly ATP/ADP) from the P2Y1 expressing cells can create conditions in which a response to an agonist such as 2MeSATP can only be seen in the presence of a competitive antagonist.

PET imaging of HER1-expressing xenografts in mice with 86Y-CHX-A''-DTPA-cetuximab

International Nuclear Information System (INIS)

Nayak, Tapan K.; Regino, Celeste A.S.; Milenic, Diane E.; Garmestani, Kayhan; Baidoo, Kwamena E.; Brechbiel, Martin W.; Wong, Karen J.; Szajek, Lawrence P.

2010-01-01

Cetuximab is a recombinant, human/mouse chimeric IgG 1 monoclonal antibody that binds to the epidermal growth factor receptor (EGFR/HER1). Cetuximab is approved for the treatment of patients with HER1-expressing metastatic colorectal cancer. Limitations in currently reported radiolabeled cetuximab for PET applications prompted the development of 86 Y-CHX-A''-DTPA-cetuximab as an alternative for imaging HER1-expressing cancer. 86 Y-CHX-A''-DTPA-cetuximab can also serve as a surrogate marker for 90 Y therapy. Bifunctional chelate, CHX-A''-DTPA was conjugated to cetuximab and radiolabeled with 86 Y. In vitro immunoreactivity was assessed in HER1-expressing A431 cells. In vivo biodistribution, PET imaging and noncompartmental pharmacokinetics were performed in mice bearing HER1-expressing human colorectal (LS-174T and HT29), prostate (PC-3 and DU145), ovarian (SKOV3) and pancreatic (SHAW) tumor xenografts. Receptor blockage was demonstrated by coinjection of either 0.1 or 0.2 mg cetuximab. 86 Y-CHX-A''-DTPA-cetuximab was routinely prepared with a specific activity of 1.5-2 GBq/mg and in vitro cell-binding in the range 65-75%. Biodistribution and PET imaging studies demonstrated high HER1-specific tumor uptake of the radiotracer and clearance from nonspecific organs. In LS-174T tumor-bearing mice injected with 86 Y-CHX-A''-DTPA-cetuximab alone, 86 Y-CHX-A''-DTPA-cetuximab plus 0.1 mg cetuximab or 0.2 mg cetuximab, the tumor uptake values at 3 days were 29.3 ± 4.2, 10.4 ± 0.5 and 6.4 ± 0.3%ID/g, respectively, demonstrating dose-dependent blockage of the target. Tumors were clearly visualized 1 day after injecting 3.8-4.0 MBq 86 Y-CHX-A''-DTPA-cetuximab. Quantitative PET revealed the highest tumor uptake in LS-174T (29.55 ± 2.67%ID/cm 3 ) and the lowest tumor uptake in PC-3 (15.92 ± 1.55%ID/cm 3 ) xenografts at 3 days after injection. Tumor uptake values quantified by PET were closely correlated (r 2 = 0.9, n = 18) with values determined by biodistribution studies

Waste Isolation Pilot Plant Annual Site Environmental Report for 2010

International Nuclear Information System (INIS)

2011-01-01

The purpose of the Waste Isolation Pilot Plant (WIPP) Annual Site Environmental Report for 2010 (ASER) is to provide information required by U.S. Department of Energy (DOE) Order 231.1A, Environment, Safety, and Health Reporting. Specifically, the ASER presents summary environmental data to: (1) Characterize site environmental management performance. (2) Summarize environmental occurrences and responses reported during the calendar year. (3) Confirm compliance with environmental standards and requirements. (4) Highlight significant environmental accomplishments, including progress toward the DOE Environmental Sustainability Goals made through implementation of the WIPP Environmental Management System (EMS). The DOE Carlsbad Field Office (CBFO) and the management and operating contractor (MOC), Washington TRU Solutions LLC (WTS), maintain and preserve the environmental resources at the WIPP. DOE Order 231.1A; DOE Order 450.1A, Environmental Protection Program; and DOE Order 5400.5, Radiation Protection of the Public and the Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and workers, and preservation of the environment. This report was prepared in accordance with DOE Order 231.1A, which requires that DOE facilities submit an ASER to the DOE Headquarters Chief Health, Safety, and Security Officer. The WIPP Hazardous Waste Facility Permit Number NM4890139088-TSDF (Permit) further requires that the ASER be provided to the New Mexico Environment Department (NMED).

Waste Isolation Pilot Plant Annual Site Environmental Report for 2010

Energy Technology Data Exchange (ETDEWEB)

None

2011-09-01

The purpose of the Waste Isolation Pilot Plant (WIPP) Annual Site Environmental Report for 2010 (ASER) is to provide information required by U.S. Department of Energy (DOE) Order 231.1A, Environment, Safety, and Health Reporting. Specifically, the ASER presents summary environmental data to: (1) Characterize site environmental management performance. (2) Summarize environmental occurrences and responses reported during the calendar year. (3) Confirm compliance with environmental standards and requirements. (4) Highlight significant environmental accomplishments, including progress toward the DOE Environmental Sustainability Goals made through implementation of the WIPP Environmental Management System (EMS). The DOE Carlsbad Field Office (CBFO) and the management and operating contractor (MOC), Washington TRU Solutions LLC (WTS), maintain and preserve the environmental resources at the WIPP. DOE Order 231.1A; DOE Order 450.1A, Environmental Protection Program; and DOE Order 5400.5, Radiation Protection of the Public and the Environment, require that the affected environment at and near DOE facilities be monitored to ensure the safety and health of the public and workers, and preservation of the environment. This report was prepared in accordance with DOE Order 231.1A, which requires that DOE facilities submit an ASER to the DOE Headquarters Chief Health, Safety, and Security Officer. The WIPP Hazardous Waste Facility Permit Number NM4890139088-TSDF (Permit) further requires that the ASER be provided to the New Mexico Environment Department (NMED).

Crystallo-chemistry of actinide nitrides (U1-yPuy)N and effect of impurities

International Nuclear Information System (INIS)

Beauvy, M.; Coulon-Picard, E.; Pelletier, M.

2004-01-01

Investigations on actinide nitrides has been done in our Laboratories for Fast Breeder Reactors since the seventies and some properties are reported to show the interest for these fuels. Today, the actinide nitrides are reconsidered as possible fuels for the future fission reactors (GFR and LMFR selected by the international forum Generation IV). The results of new investigations on crystal structure of mixed mono-nitrides (U,Pu)N, and the effects of oxygen and carbon contaminations on this structure are presented. The cubic 'NaCl-fcc' type structure of actinide nitrides AnN with space group O5/h-Fm3m does not respect the 'Vegard law' model for the mixed nitrides (U 1-y Pu y )N. These nitrides are usually considered with strong metallic character associated with partial ionic bonding, but the ionic contribution in the An-N bonding determined in this work is very important and near 41.6% for UN and PuN. From results published on resistivity of mixed nitrides, the data on bonding must be also modified for partial covalence. This is in good agreement with the experimental lattice parameters which are not compatible with dominant metallic bonding. The numbers of bonding electrons in the nitrides (U 1-y Pu y )N are reevaluated and the low values proposed comparatively with those previously published confirm the strong ionic character with high concentration of An 3+ ions. The solubility of oxygen and carbon in actinide nitrides (U 1-y Pu y )N are discussed from measurements on volume concentration of actinide oxide phase, total oxygen and carbon contents, and lattice parameter of nitrides. The oxygen solubility limit in UN is near 1000 ppm, with a lightly higher value of 1200 ppm for the mixed nitride (U 0.8 Pu 0.2 )N. The effects of oxygen or carbon atoms in the lattice of (U 1-y Pu y )N are analysed

An analysis of the distribution and dose response of chromosome aberrations in human lymphocytes after in vitro exposure to 137cesium gamma radiation

International Nuclear Information System (INIS)

Doggett, N.A.; McKenzie, W.H.

1983-01-01

The chromosome aberration yield for human lymphocytes exposed in vitro to various doses of 137 Cesium has been studied. Dicentric, total acentric, and excess acentric data were seen to follow a Possion distribution. Calculated total hits demonstrated over-dispersion which could possibly be accounted for by a greater occurrence of single-hit phenomena being repaired than two-hit exchange processes. The resulting distribution generally contained an under-representation of cells with odd numbers of hits and an over-representation of zero-and even-hit classes as compared with Poisson predicted values. The relationship between dicentric yield and dose received in rads was fitted to the linear-quadratic formula Y=αD+βD 2 for dicentrics, yielding values of (20.1+-3.8)x10 -4 (aberrations/cell)/rad and (1.89+-0.75)x10 -6 (aberrations/cell)/rad 2 for α and β respectively. A plot of percent ''normal'' cells versus the dose in rads resembled cell survival curves and was fitted to the relation P(D)=100 esup(-Y) where Y=αD+αD 2 with α=(23+-11)x10 -4 rad -1 and β=(8.3+-2.5)x10 -6 rad -2 . A possible use of scoring ''normal'' cells for purposes of biological dosimetry is presented. (orig.)

CONSTITUYENTES VOLÁTILES DE DOS VARIEDADES DE GUAYABA (Psidium guajava L.: Palmira ICA-1 y Glum Sali

Directory of Open Access Journals (Sweden)

Clara E Quijano C

2010-08-01

Full Text Available Los constituyentes volátiles de la pulpa de dos variedades de guayaba (Psidium guajava L (Palmira ICA-1 y Glum Salí, fueron obtenidos por extracción L-L (pentano: diclorometano 1:1; los extractos concentrados se fraccionaron por Cromatografía de Columna y se analizaron por CGAR Y CGAR-EM. De la variedad Palmira - ICA-1 se identificaron 86 compuestos, siendo mayoritarios el acetato de cinamilo, el acetato de (Z 3-hexenilo y el alcohol cinnamílico. En la variedad Glum Sali, se determinaron 77 constituyentes, de los cuales predominaron cuantitativamente el (E-2-hexenal, el hexanal y el tetradecano. La principal diferencia en la composición de volátiles entre las dos variedades es el alto contenido de esteres en la primera variedad, mientras que en la Glum Sali predominaron los hidrocarburos y los aldehidos C(,. De los compuestos volátiles identificados en este trabajo, la 4- hidroxi-4-metil-2-pentanona, la 3-heptanona, el 3-hidroxibutanoato de etilo, el acetato de 2-hidroxietilo, el 1,2-propanodiol, el 1,2-etanodiol, el acetato de 3-metilbutilo y el 3-metil-2 butanol son reportados por primera vez como constituyentes del aroma de guayaba.

Structure and magnetic properties of GdxY1−xFeO3 obtained by mechanosynthesis

International Nuclear Information System (INIS)

Bolarín-Miró, A.M.; Sánchez-De Jesús, F.; Cortés-Escobedo, C.A.; Valenzuela, R.; Ammar, S.

2014-01-01

Highlights: • Orthohombic GDxY1-xFeO3 was obtained by mechanosynthesis after 5 h of milling. • Mechanosynthesized GdxY1-xFeO3 show weak ferromagnetic behavior. • Mechanosynthesis promotes unexpected magnetic properties in GdxY1-xFeO3. • The maximum magnetization that was reached 7.7 emu/g for Gdo.75Y0.25FeO3. • For Gd0.5Y0.5FeO3, the magnetization decreases down to 2.1 emu/g. -- Abstract: Solid solutions of yttrium–gadolinium orthoferrites Gd x Y 1−x FeO 3 (0 ⩽ x ⩽ 1) were prepared by high-energy ball milling. The aim of this work was to study the influence of the synthesis parameters on the crystal structure and the magnetic behavior of these solid solutions. The precursors, Fe 2 O 3 , Y 2 O 3 and Gd 2 O 3 , mixed in a stoichiometric ratio to obtain these orthoferrites, were milled for different times (up to 5 h). X-ray diffraction and Rietveld refinement were used to elucidate the phase transformation as a function of the milling time. Results showed the complete formation of orthoferrite with an orthorhombic structure (S.G. Pbnm) without any annealing after 5 h of milling for all of the compositions. The effect of the synthesis process and the x value on the crystal structure and the magnetic properties were also studied. All of the synthesized powders demonstrated weak ferromagnetic behavior. In particular, an increase in the maximum magnetization for all the compositions was found, with a maximum that reached 7.7 emu/g for Gd 0.75 Y 0.25 FeO 3 . For Gd 0.5 Y 0.5 FeO 3 , the magnetization decreases down to 2.1 emu/g. A small contamination of metallic Fe was confirmed through electron spin resonance experiments