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Sample records for canavanine-glycine-bromothymol blue agar

  1. Adsorptive removal of methylene blue by agar: effects of NaCl and ethanol

    PubMed Central

    2012-01-01

    Adsorption of methylene blue (MB) on agar was investigated as a function of temperature (308-328 K), different concentrations of NaCl and HCl and various weight percentages of binary mixtures of ethanol with water. It was observed that the maximum experimental adsorption capacity, qm, exp, in water is up to 50 mg g-1 and decreases with increase in weight percentage of ethanol and NaCl and HCl concentration compared to that of water. Analysis of data using ARIAN model showed that MB adsorbs as monomer and dimer on the surface of agar. Binding constants of MB to agar were calculated using the Temkin isotherm. The process is exothermic in water and other solutions. The mean adsorption energy (E) value indicated binding of MB to agar is chemical adsorption. Kinetics of this interaction obeys from the pseudo-second-order model and diffusion of the MB molecules into the agar is the main rate-controlling step. PMID:22339759

  2. ACINETOBACTER SPP.: DISTINCT MORPHOLOGY ON EOSIN METHYLENE BLUE AGAR AS AN AID TO IDENTIFICATION IN DRINKING WATER

    EPA Science Inventory

    'Acinetobacter calcoaceticus', frequently found in drinking waters and implicated in nosocomial infections, was presumptively identified by its tiny, blue colonial appearance on Levine eosin methylene blue agar. All of the 33 isolates from drinking water showing this distinctive ...

  3. FIRST REPORT ON Cryptococcus neoformans IN PIGEON EXCRETA FROM PUBLIC AND RESIDENTIAL LOCATIONS IN THE METROPOLITAN AREA OF CUIAB, STATE OF MATO GROSSO, BRAZIL

    PubMed Central

    Takahara, Doracilde Terumi; Lazra, Mrcia dos Santos; Wanke, Bodo; Trilles, Luciana; Dutra, Valria; de Paula, Daphine Ariadne Jesus; Nakazato, Luciano; Anzai, Mariana Caselli; Leite, Diniz Pereira; Paula, Claudete Rodrigues; Hahn, Rosane Christine

    2013-01-01

    SUMMARY Cryptococcosis is a severe systemic mycosis caused by two species of Cryptococcus that affect humans and animals: C. neoformans and C. gattii. Cosmopolitan and emergent, the mycosis results from the interaction between a susceptible host and the environment. The occurrence of C. neoformans was evaluated in 122 samples of dried pigeon excreta collected in 49 locations in the City of Cuiab, State of Mato Grosso, Brazil, including public squares (n = 5), churches (n = 4), educational institutions (n = 3), health units (n = 8), open areas covered with asbestos (n = 4), residences (n = 23), factory (n = 1) and a prison (n = 1). Samples collected from July to December of 2010 were seeded on Niger seed agar (NSA). Dark brown colonies were identified by urease test, carbon source assimilation tests and canavanine-glycine-bromothymol blue medium. Polymerase chain reaction primer pairs specific for C. neoformans were also used for identification. Cryptococcus neoformans associated to pigeon excreta was isolated from eight (6.6%) samples corresponding to six (12.2%) locations. Cryptococcus neoformans was isolated from urban areas, predominantly in residences, constituting a risk of acquiring the disease by immunocompromised and immunocompetent individuals. PMID:24213188

  4. First report on Cryptococcus neoformans in pigeon excreta from public and residential locations in the metropolitan area of Cuiabá, State of Mato Grosso, Brazil.

    PubMed

    Takahara, Doracilde Terumi; Lazéra, Márcia dos Santos; Wanke, Bodo; Trilles, Luciana; Dutra, Valéria; Paula, Daphine Ariadne Jesus de; Nakazato, Luciano; Anzai, Mariana Caselli; Leite Júnior, Diniz Pereira; Paula, Claudete Rodrigues; Hahn, Rosane Christine

    2013-01-01

    Cryptococcosis is a severe systemic mycosis caused by two species of Cryptococcus that affect humans and animals: C. neoformans and C. gattii. Cosmopolitan and emergent, the mycosis results from the interaction between a susceptible host and the environment. The occurrence of C. neoformans was evaluated in 122 samples of dried pigeon excreta collected in 49 locations in the City of Cuiabá, State of Mato Grosso, Brazil, including public squares (n = 5), churches (n = 4), educational institutions (n = 3), health units (n = 8), open areas covered with asbestos (n = 4), residences (n = 23), factory (n = 1) and a prison (n = 1). Samples collected from July to December of 2010 were seeded on Niger seed agar (NSA). Dark brown colonies were identified by urease test, carbon source assimilation tests and canavanine-glycine-bromothymol blue medium. Polymerase chain reaction primer pairs specific for C. neoformans were also used for identification. Cryptococcus neoformans associated to pigeon excreta was isolated from eight (6.6%) samples corresponding to six (12.2%) locations. Cryptococcus neoformans was isolated from urban areas, predominantly in residences, constituting a risk of acquiring the disease by immunocompromised and immunocompetent individuals. PMID:24213188

  5. Cryptococcus species identification by multiplex PCR.

    PubMed

    Leal, Ana Lusia; Faganello, Josiane; Bassanesi, Maria Cristina; Vainstein, Marilene H

    2008-06-01

    Members of the Cryptococcus species complex are encapsulated basidiomycetous yeasts, which can affect the central nervous system (CNS) and if untreated may cause meningitis. Cryptococcus neoformans is an opportunistic pathogen causing infections mainly in immunocompromised individuals. Cryptococcus gattii is a primary pathogen responsible for a high incidence of cryptococcomas in the lung and brain and shows a delayed response to antifungal therapy. The differentiation between the two species is primarily based on their growth on and color change of canavanine - glycine-bromothymol blue agar (CGB). Since this test is not always reliable, a multiplex PCR to identify both Cryptococcus species using more than 130 samples was standardized and the results obtained compared to those with the CGB test, using the Crypto Check serotyping kit as the standard. The multiplex PCR was shown to be more specific than the CGB test, in that results obtained with it were in agreement with those from serotyping all the samples, while the data from the CGB test disagreed with 6 out of 131 samples. PMID:18415847

  6. Cryptococcus spp isolated from dust microhabitat in Brazilian libraries

    PubMed Central

    2012-01-01

    Background The Cryptococcus spp is currently composed of encapsulated yeasts of cosmopolitan distribution, including the etiological agents of cryptococcosis. The fungus are found mainly in substrates of animal and plant origin. Human infection occurs through inhalation of spores present in the environment. Methods Eighty-four swab collections were performed on dust found on books in three libraries in the city of Cuiabá, state of Mato Grosso, Brazil. The material was seeded in Sabouraud agar and then observed for characteristics compatible with colonies with a creamy to mucous aspect; the material was then isolated in birdseed (Niger) agar and cultivated at a temperature of 37°C for 5 to 7 days. Identification of isolated colonies was performed by microscopic observation in fresh preparations dyed with India ink, additional tests performed on CGB (L-canavanine glycine bromothymol blue), urea broth, and carbohydrate assimilation tests (auxanogram). Results Of the 84 samples collected from book dust, 18 (21.4%) were positive for Cryptococcus spp totalizing 41 UFC’s. The most frequently isolated species was C. gattii 15 (36.6%); followed by C. terreus, 12 (29.3%); C. luteolus 4 (9.8%); C. neoformans, and C. uniguttulatus 3 (7.3%), and C. albidus and C. humiculus with 2 (4.6%) of the isolates. Conclusion The high biodiversity of the yeasts of the Cryptococcus genus, isolated from different environmental sources in urban areas of Brazil suggests the possibility of individuals whose immune systems have been compromised or even healthy individuals coming into sources of fungal propagules on a daily bases throughout their lives. This study demonstrates the acquisition possible of cryptococcosis infection from dust in libraries. PMID:22682392

  7. Cryptococcus gattii-Induced Infections in Dogs from Southern Brazil.

    PubMed

    Headley, Selwyn Arlington; Di Santis, Giovana Wingeter; de Alcântara, Brígida Kussumoto; Costa, Thais Correa; da Silva, Elisangela Olegário; Pretto-Giordano, Lucienne Garcia; Gomes, Lucas Alécio; Alfieri, Amauri Alcindo; Bracarense, Ana Paula Frederico R L

    2015-10-01

    Cryptococcus gattii-induced cryptococcosis is an emerging infectious disease of humans and animals worldwide, with rare descriptions of this infection in domestic animals from Brazil. This study presents the findings associated with C. gattii in dogs from Londrina, Paraná, Southern Brazil. Two dogs, a 3-year-old, female German shepherd and a 6-year-old, male Boxer, were evaluated by a combination of pathological, mycological, and molecular diagnostic techniques. Significant pathological alterations included cryptococcal lymphadenitis, meningoencephalitis, tonsillitis, and rhinitis with nasal cryptococcomas in the German shepherd dog, while cryptococcal lymphadenitis and pneumonia were observed in the Boxer; both dogs had pseudocystic cryptococcosis. The mucicarmine histochemical stain readily identified the intralesional cryptococcal budding organisms in all affected tissues. Mycological culture and isolation confirmed the yeasts as C. gattii due to positive reaction with the L-canavanine glycine bromothymol blue agar. A PCR assay using the internal transcribed spacers (ITS)1 and ITS2 primers, which target the ITS1 and 2 regions including the 5.8S rRNA gene, amplified the desired amplicons; direct sequencing confirmed the isolate as C. gattii. ITS nucleotide differentiation demonstrated that the isolate forms part of the ITS type 4 Cryptococcus organisms which corresponds to the C. gattii VGII molecular subtype or the RAPD type 2 Cryptococcus organisms. Collectively, these findings confirmed the participation of C. gattii in the etiopathogenesis of the lesions observed in these dogs and expanded the epidemiological niche of this important mycotic agent to include Southern Brazil. It is noteworthy to mention that previous epidemiological studies have suggested that C. gattii-induced cryptococcosis is more frequently diagnosed in Northern relative to Southern Brazil, so these findings might suggest an expansion of the distribution of this agent within continental Brazil. PMID:26025661

  8. Use of urease-bromothymol blue-agar method for large-scale testing of urine on grain and seeds.

    PubMed

    Valdes, P A; Ziobro, G C; Ferrera, R S

    1996-01-01

    The current AOAC method (963.28) for large-scale (50 g) testing of urine on grain is based on the reaction of sodium in urine with magnesium uranyl acetate. Detection of sodium suggests that urine is present and that a test for urea is appropriate. Urea is detected with urease-bromothymol blue-paper and is confirmed through its reaction with xanthydrol to form dixanthylurea crystals, which are detected microscopically. The initial nonspecific test for sodium can be influenced by the presence of salt or other sodium compounds. Furthermore, the magnesium uranyl acetate spray used in Method 963.28 potentially exposes the analyst to the aerosol of a volatile, toxic uranium compound. Excess reagents and analyzed test portions must be disposed of as radioactive waste. In addition, Method 963.28 requires several steps to determine the presence of urea. The alternative AOAC method (972.41) tests for the presence of urea from urine on individual seeds. Urea is enzymatically decomposed to ammonia and carbon dioxide by urease. Liberated ammonia shifts the pH, changing the color of the indicator in the agar from yellow to blue. This study adapts Method 972.41 to larger test samples. Up to 25 g grains and seeds are sprayed with urease test agar instead of being individually immersed in the urease test agar. The modified method was used to analyze urea on seeds and grains of 24 plants from 4 families. The method has a limit of detection of one seed contaminated with 1 microgram urea. PMID:8757445

  9. Comparison of biotyping methods as alternative identification tools to molecular typing of pathogenic Cryptococcus species in sub-Saharan Africa.

    PubMed

    Nyazika, Tinashe K; Robertson, Valerie J; Nherera, Brenda; Mapondera, Prichard T; Meis, Jacques F; Hagen, Ferry

    2016-03-01

    Cryptococcal meningitis is the leading fungal infection and AIDS defining opportunistic illness in patients with late stage HIV infection, particularly in South-East Asia and sub-Saharan Africa. Given the high mortality, clinical differences and the extensive ecological niche of Cryptococcus neoformans and Cryptococcus gattii species complexes, there is need for laboratories in sub-Sahara African countries to adopt new and alternative reliable diagnostic algorithms that rapidly identify and distinguish these species. We biotyped 74 and then amplified fragment length polymorphism (AFLP) genotyped 66 Cryptococcus isolates from a cohort of patients with HIV-associated cryptococcal meningitis. C. gattii sensu lato was isolated at a prevalence of 16.7% (n = 11/66) and C. neoformans sensu stricto was responsible for 83.3% (n = 55/66) of the infections. l-Canavanine glycine bromothymol blue, yeast-carbon-base-d-proline-d-tryptophan and creatinine dextrose bromothymol blue thymine were able to distinguish pathogenic C. gattii sensu lato from C. neoformans sensu stricto species when compared with AFLP genotyping. This study demonstrates high C. gattii sensu lato prevalence in Zimbabwe. In addition, biotyping methods can be used as alternative diagnostic tools to molecular typing in resource-limited areas for differentiating pathogenic Cryptococcus species. PMID:26661484

  10. First Identification of Autochthonous Cryptococcus neoformans var. gattii Isolated from Goats with Predominantly Severe Pulmonary Disease in Spain

    PubMed Central

    Baró, Teresa; Torres-Rodríguez, Josep M.; De Mendoza, Miguel Hermoso; Morera, Yolanda; Alía, Concepción

    1998-01-01

    Cryptococcus neoformans var. gattii is associated with Eucalyptus trees growing in various tropical and subtropical regions of the world. The identification of 13 autochthonous strains of C. neoformans var. gattii in Spain is reported. These strains were isolated from lung (10 samples), liver (1 sample), and brain (2 samples) tissue specimens from six goats suffering from predominantly severe pulmonary disease that were autopsied. The animals were members of five different herds of goats grazing in rural areas of the province of Cáceres (Extremadura, Spain). Between 1990 and 1994, there were five outbreaks, in which between 2.5 and 12% of the goats were affected. Although respiratory symptoms (pneumonia) associated with cachexia were the predominant clinical picture in all outbreaks, brain and liver involvement was also documented in three of the five outbreaks. Biotyping was performed by culturing the isolates on l-canavanine-glycine-bromothymol blue medium and testing them for the assimilation of d-proline and d-tryptophan. Serotyping by agglutination tests confirmed the characterization of all strains as C. neoformans var. gattii serotype B. This is the first confirmation of the presence of this variety in Spain, with a peculiar ability to produce severe pulmonary and systemic disease in normal goats, particularly in the form of outbreaks of pneumonia in association with cachexia. PMID:9466758

  11. Genotypic diversity of environmental Cryptococcus neoformans isolates from Northern Portugal.

    PubMed

    Ferreira, Ana Sofia; Sampaio, Ana; Maduro, Ana Paula; Silva, Inês; Teles, Fernando; Martins, Maria da Luz; Inácio, João

    2014-02-01

    The Cryptococcus neoformans/C. gattii species complex members are the main agents of systemic cryptococcosis. This disease is believed to be acquired from the environment via fungal cell inhalation. Often, isolates recovered from environmental and clinical sources have proven to be genotypically similar. We assessed the occurrence of C. neoformans and C. gattii in environmental substrates collected in a Portuguese region. Twenty-eight isolates were identified as C. neoformans - five from decaying Eucalyptus leaves and 23 from domestic pigeon droppings. The isolates were genotyped using a URA5-RFLP approach. The C. neoformans VNIV (53.6%, n = 15) and VNI (32.1%, n = 9) genotypes were abundantly present among environmental isolates. The hybrid VNIII (14.3%, n = 4) genotype was underrepresented and the VNII was not found. Cryptococcus gattii was also not found although some isolates yielded a positive canavanine-glycine-bromothymol blue test. PMID:23848429

  12. Genotyping of Cryptococcus neoformans isolated from captive birds in Uberaba, Minas Gerais, Brazil.

    PubMed

    Ferreira-Paim, Kennio; Andrade-Silva, Leonardo; Mora, Delio Jose; Pedrosa, André Luiz; Rodrigues, Virmondes; Silva-Vergara, Mario León

    2011-09-01

    To evaluate Cryptococcus spp. molecular types isolated from captive birds' droppings, an epidemiological survey was carried out in Uberaba, Minas Gerais, Brazil, from December 2006 to September 2008. A total of 253 samples of bird excreta (120 fresh and 133 dry) were collected from pet shop cages and houses in different neighbourhoods. Cryptococcus neoformans was isolated in 19 (14.28%) dry samples and one fresh sample (0.84%). Cryptococcus laurentii was recovered from seven (5.26%) dry samples, but not in the fresh samples. The canavanine-glycine-bromothymol blue test was positive in all but one of the C. laurentii isolates. Cryptococcus neoformans molecular typing was performed using URA5-RFLP and the mating type locus using mating type specific PCR. Nineteen (95.0%) presented genotype VNI and one VNII (5.0%). In addition, all isolates presented mating type α. Thus, the genotype of the environmental C. neoformans isolates observed in this study is in accordance with others already reported around the world and adds information about its distribution in Brazil. Cryptococcus laurentii strains were typed using URA5-RFLP and M13 fingerprinting, which showed similar profiles among them. Thus, despite the low number of C. laurentii isolates analysed, their molecular profile is different from another already reported. PMID:20492533

  13. In vitro susceptibility characteristics of Cryptococcus neoformans varieties from AIDS patients in Goiânia, Brazil.

    PubMed

    de F L Fernandes, Orionalda; Passos, Xisto S; Souza, Lúcia K H; Miranda, André T B; Cerqueira, Carlos Henrique P V; Silva, Maria do Rosário R

    2003-09-01

    Sixty clinical isolates of Cryptococcus neoformans from AIDS from Goiânia, state of Goiás, Brazil, were characterized according to varieties, serotypes and tested for antifungal susceptibility. To differentiate the two varieties was used L-canavanine-glycine-bromothymol blue medium and to separate the serotypes was used slide agglutination test with Crypto Check Iatron. The Minimal Inhibitory Concentration (MIC) of fluconazole, itraconazole, and amphotericin B were determined by the National Committee for Clinical Laboratory Standards macrodilution method. Our results identified 56 isolates as C. neoformans var. neoformans serotype A and 4 isolates as C. neoformans var. gattii serotype B. MIC values for C. neoformans var. gattii were higher than C. neoformans var. neoformans. We verified that none isolate was resistant to itraconazole and to amphotericin B, but one C. neoformans var. neoformans and three C. neoformans var. gattii isolates were resistant to fluconazole. The presence of C. neoformans var. gattii fluconazole resistant indicates the importance of determining not only the variety of C. neoformans infecting the patients but also measuring the MIC of the isolate in order to properly orient treatment. PMID:14595465

  14. 21 CFR 184.1115 - Agar-agar.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Agar-agar. 184.1115 Section 184.1115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS §...

  15. Agar degradation by microorganisms and agar-degrading enzymes.

    PubMed

    Chi, Won-Jae; Chang, Yong-Keun; Hong, Soon-Kwang

    2012-05-01

    Agar is a mixture of heterogeneous galactans, mainly composed of 3,6-anhydro-L-galactoses (or L-galactose-6-sulfates) D-galactoses and L-galactoses (routinely in the forms of 3,6-anhydro-L-galactoses or L-galactose-6-sulfates) alternately linked by β-(1,4) and α-(1,3) linkages. It is a major component of the cell walls of red algae and has been used in a variety of laboratory and industrial applications, owing to its jellifying properties. Many microorganisms that can hydrolyze and metabolize agar as a carbon and energy source have been identified in seawater and marine sediments. Agarolytic microorganisms commonly produce agarases, which catalyze the hydrolysis of agar. Numerous agarases have been identified in microorganisms of various genera. They are classified according to their cleavage pattern into three types-α-agarase, β-agarase, and β-porphyranase. Although, in a broad sense, many other agarases are involved in complete hydrolysis of agar, most of those identified are β-agarases. In this article we review agarolytic microorganisms and their agar-hydrolyzing systems, covering β-agarases as well as α-agarases, α-neoagarobiose hydrolases, and β-porphyranases, with emphasis on the recent discoveries. We also present an overview of the biochemical and structural characteristics of the various types of agarases. Further, we summarize and compare the agar-hydrolyzing systems of two specific microorganisms: Gram-negative Saccharophagus degradans 2-40 and Gram-positive Streptomyces coelicolor A3(2). We conclude with a brief discussion of the importance of agarases and their possible future application in producing oligosaccharides with various nutraceutical activities and in sustainably generating stock chemicals for biorefinement and bioenergy. PMID:22526785

  16. Blue on Blues.

    PubMed

    Edlin, M

    1998-05-01

    Activists and regulators won't let Blue Cross & Blue Shield plans forget their roots. In fact, when these historic not-for-profits announce intentions to merge with other Blues or go for-profit, states demand repayment for years of foregone taxes. Charity has become the spoiler, dashing deal after deal. PMID:9646734

  17. Preparation of hydroxypropyl agars and their properties.

    PubMed

    Zhang, Xiaodong; Liu, Xin; Cao, Mingzhao; Xia, Kai; Zhang, Yuqiao

    2015-09-20

    A series of hydroxypropyl agars (HPAs) with different hydroxypropyl molar substitution (MS) were prepared and their physicochemical properties were characterized. After hydroxypropylation, the dissolving temperature, the gelling temperature, the gel melting temperature, the gel strength, and the thermal stability of agar all decreased except that its hygroscopicity increased. The gel skeleton structures of raw agar and HPAs were all of the porous network structures, but the pores of gel skeleton structure of HPAs became smaller and denser. PMID:26050892

  18. 48 CFR 401.371 - AGAR Advisories.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false AGAR Advisories. 401.371 Section 401.371 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL AGRICULTURE ACQUISITION REGULATION SYSTEM Agency Acquisition Regulations 401.371 AGAR Advisories. The SPE may issue...

  19. 48 CFR 401.371 - AGAR Advisories.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false AGAR Advisories. 401.371 Section 401.371 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL AGRICULTURE ACQUISITION REGULATION SYSTEM Agency Acquisition Regulations 401.371 AGAR Advisories. The SPE may issue...

  20. 48 CFR 401.371 - AGAR Advisories.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false AGAR Advisories. 401.371 Section 401.371 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL AGRICULTURE ACQUISITION REGULATION SYSTEM Agency Acquisition Regulations 401.371 AGAR Advisories. The SPE may issue...

  1. 48 CFR 401.371 - AGAR Advisories.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false AGAR Advisories. 401.371 Section 401.371 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL AGRICULTURE ACQUISITION REGULATION SYSTEM Agency Acquisition Regulations 401.371 AGAR Advisories. The SPE may issue...

  2. 48 CFR 401.371 - AGAR Advisories.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false AGAR Advisories. 401.371 Section 401.371 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE GENERAL AGRICULTURE ACQUISITION REGULATION SYSTEM Agency Acquisition Regulations 401.371 AGAR Advisories. The SPE may issue...

  3. Agar polysaccharides from Gracilaria species (Rhodophyta, Gracilariaceae).

    PubMed

    Marinho-Soriano, E

    2001-07-26

    Yield, physical and chemical properties of agar from three agarophytes species (Gracilaria gracilis, G. dura and G. bursa-pastoris) were determined. The agar yield from the three species varied significantly (P<0.01). The highest yields of agar (34.8%) and the lowest (30%) were obtained from G. bursa-pastoris and G. gracilis, respectively. Highest gel strength (630+/-15 g cm(-2)) was obtained from agar extracted from G. gracilis and lowest from G. bursa-pastoris (26+/-3.6 g cm(-2)). The values of 3,6-anhydrogalactose were similar for G. gracilis and G. dura and there were no significant differences among the species. The sulfate contents varied significantly (P<0.01) and the higher value was obtained from G. bursa-pastoris. Among the three species, G. gracilis showed superior agar quality than the other two species, hence it can be considered a good potential source for industrial use. PMID:11472802

  4. Prussian Blue

    MedlinePlus

    ... Prussian Blue Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir What is Prussian blue? How does Prussian blue work? Who can take Prussian blue? How is Prussian blue given? What are the side effects of Prussian blue? Where can I get Prussian ...

  5. Some Experiments With Agar-Grown Seedlings

    ERIC Educational Resources Information Center

    Freeland, P. W.

    1973-01-01

    Two percent agar gel is reported as a better medium for germination and growth studies. Students can be encouraged to undertake many simple experiments and make precise observations by using this medium. (PS)

  6. Characterization of physicochemical properties of carboxymethyl agar.

    PubMed

    Cao, Mingzhao; Liu, Xin; Luan, Jimei; Zhang, Xiaodong

    2014-10-13

    A series of carboxymethyl agars (CMAs) with different degree of substitution (DS) were prepared, and their properties were determined and analyzed. The results showed that with the increase of DS, the dissolving temperature, the gelling temperature, the gel melting temperature, the gel strength, the gel hardness, the gel fracturability, and the solution apparent viscosity of CMA all decreased, except that its gel cohesiveness and gel springiness increased. The variation process of agar molecules in solution from coil to helix could be observed by measuring the optical rotation of the solution at such a low concentration, at which even the solution could not form a gel. The gel skeleton microstructures of both agar and CMA were of porous network structure, and the pore size of CMA became smaller and denser with the increase of its DS. After carboxymethylation, the agar hygroscopicity was improved, but its thermal stability was lowered. PMID:25037374

  7. Disk Agar Diffusion Susceptibility Testing of Yeasts

    PubMed Central

    Saubolle, Michael A.; Hoeprich, Paul D.

    1978-01-01

    A disk agar diffusion method was developed for testing the susceptibility of rapidly growing yeasts in vitro. A totally defined, completely synthetic agar culture medium (synthetic amino acid medium, fungal) and clinical isolates of Candida spp. and Torulopsis glabrata were used. Turbidimetric adjustment of cell suspensions resulted in standard, reproducible inocula, which gave sharp, clear zones of inhibition when applied by an agar overlay method. Optimal disk loads were determined for amphotericin B, amphotericin B methyl ester, 5-fluorocytosine, clotrimazole, and miconazole. Disk potencies were stable over a 2-month period when stored in a vacuum desiccator at −30°C. Using an error ratebounded classification, the zones of inhibition were correlated with both broth dilution and agar dilution minimum inhibitory concentrations (MICs). With amphotericin B and amphotericin B methyl ester, all isolates were susceptible, yielding zone diameters which clustered within 5 mm. Overall correlations between zone diameters and broth dilution MICs with 5-fluorocytosine, miconazole, and clotrimazole were 97, 96, and 82% (excluding T. glabrata), respectively; correlations of zone diameters with agar dilution MICs were 96, 92, and 88%, respectively. Disk diffusion susceptibility testing of yeasts appears to be generally applicable. However, when results are equivocal, quantitative test methods should be used. PMID:568910

  8. Pigments of fly agaric (Amanita muscaria).

    PubMed

    Stintzing, Florian; Schliemann, Willibald

    2007-01-01

    The complex pigment pattern of fly agaric (Amanita muscaria) cap skins has been studied by LC-DAD and mass spectrometry. Among the betaxanthins the corresponding derivatives of serine, threonine, ethanolamine, alanine, Dopa, phenylalanine and tryptophan are reported for the first time to contribute to the pigment pattern of fly agarics. Betalamic acid, the chromophoric precursor of betaxanthins and betacyanins, muscaflavin and seco-dopas were also detected. Furthermore, the red-purple muscapurpurin and the red muscarubrin were tentatively assigned while further six betacyanin-like components could not be structurally allocated. Stability studies indicated a high susceptibility of pigment extracts to degradation which led to rapid colour loss thus rendering a complete characterization of betacyanin-like compounds impossible at present. Taking into account these difficulties the presented results may be a starting point for a comprehensive characterization of the pigment composition of fly agarics. PMID:18274277

  9. Luminescent DNA- and agar-based membranes.

    PubMed

    Leones, R; Fernandes, M; Ferreira, R A S; Cesarino, I; Lima, J F; Carlos, L D; Bermudez, V de Zea; Magon, C J; Donoso, J P; Silva, M M; Pawlicka, A

    2014-09-01

    Luminescent materials containing europium ions are investigated for different optical applications. They can be obtained using bio-macromolecules, which are promising alternatives to synthetic polymers based on the decreasing oil resources. This paper describes studies of the DNA- and Agar-europium triflate luminescent membranes and its potential technological applications are expanded to electroluminescent devices. Polarized optical microscopy demonstrated that the samples are birefringent with submicrometer anisotropy. The X-ray diffraction analysis revealed predominantly amorphous nature of the samples and the atomic force microscopy images showed a roughness of the membranes of 409.0 and 136.1 nm for the samples of DNA10Eu and Agar1.11Eu, respectively. The electron paramagnetic resonance spectra of the DNA(n)Eu membranes with the principal lines at g ? 2.0 and g ? 4.8 confirmed uniform distribution of rare earth ions in a disordered matrix. Moreover, these strong and narrow resonance lines for the samples of DNA(n)Eu when compared to the Agar(n)Eu suggested a presence of paramagnetic radicals arising from the DNA matrix. The emission spectra suggested that the Eu3+ ions occupy a single local environment in both matrices and the excitation spectra monitored around the Eu emission lines pointed out that the Eu3+ ions in the Agar host were mainly excited via the broad band component rather than by direct intra-4f(6) excitation, whereas the opposite case occurred for the DNA-based sample. PMID:25924317

  10. Use of agar agar stabilized milled zero-valent iron particles for in situ groundwater remediation

    NASA Astrophysics Data System (ADS)

    Schmid, Doris; Velimirović, Milica; Wagner, Stephan; Micić Batka, Vesna; von der Kammer, Frank; Hofmann, Thilo

    2015-04-01

    A major obstacle for use of nanoscale zero-valent iron (nZVI) particles as a nontoxic material for effective in situ degradation of chlorinated aliphatic hydrocarbons (CAHs) is the high production cost. For that reason, submicro-scale milled zero-valent iron particles were recently developed (milled ZVI, UVR-FIA, Germany) by grinding macroscopic raw materials of elementary iron as a cheaper alternative to products produced by solid-state reduction. However, milled ZVI particles tend to aggregate and due to the rather large particle size (d50= 11.9 µm) also rapidly sediment. To prevent aggregation and consequently sedimentation of milled ZVI particles and therefore improve the mobility after in situ application, the use of a stabilizer is considered in literature as a most promising option. In this study, milled ZVI particles (1 g L-1 of particle concentration) were stabilized by environmentally friendly polymer agar agar (>0.5 g L-1), which had a positive impact on the milled ZVI stability. Sedimentation rate was significantly decreased by increasing the suspension viscosity. Column transport experiments were performed for bare and agar agar stabilized milled ZVI particles in commercially available fine grained quartz sand (DORSILIT® Nr.8, Gebrüder Dorfner GmbH Co, Germany) and different porous media collected from brownfields. The experiments were carried out under field relevant injection conditions of 100 m d-1. The maximal travel distance (LT) of less than 10 cm was determined for non-stabilized suspension in fine grained quartz sand, while agar agar (1 g L-1) stabilized milled ZVI suspension revealed LT of 12 m. Similar results were observed for porous media from brownfields showing that mobility of agar agar stabilized particle suspensions was significantly improved compared to bare particles. Based on the mobility data, agar agar stabilized milled zero-valent iron particles could be used for in situ application. Finally, lab-scale batch degradation experiments were performed to determine the impact of agar agar on the reactivity of milled ZVI and investigate the apparent corrosion rate of particles by quantifying the hydrogen gas generated by anaerobic corrosion of milled ZVI. The results indicate that agar agar had a positive impact on the milled ZVI stability and mobility, however adverse impact on the reactivity towards trichloroethene (TCE) was observed compared to the non-stabilized material. On the other hand, this study shows that the apparent corrosion rate of non-stabilized and agar agar stabilized milled ZVI particles is in the same order of magnitude. These data indicate that the dechlorination pathway of TCE by agar agar stabilized milled ZVI particles is possibly impacted by blocking of the reactive sites and not hydrogen revealed during particles corrosion. Finally, calculated longevity of the particles based on the apparent corrosion rate is significantly prolonged compared to the longevity of the nZVI particles reported in previous studies. This research receives funding from the European Union's Seventh Framework Programme FP7/2007-2013 under grant agreement n°309517.

  11. Comparison of recovery of airborne microorganisms in a dairy cattle facility using selective agar and thin agar layer resuscitation media.

    PubMed

    Crozier-Dodson, Beth Ann; Fung, Daniel Y C

    2002-09-01

    Thin agar layer (TAL) medium was developed at Kansas State University to improve the resuscitation of injured cells and has been shown to result in higher recovery than is obtained with selective media alone for cold-, heat-, salt-, and acid-injured cells. The experiment presented here was designed to determine the effectiveness of the TAL method for the recovery of possibly injured organisms from air. Eleven agar media were used for the experiment: tryptic soy agar (TSA), MacConkey sorbitol agar (MSA), TAL-MSA, Baird-Parker (BP) agar, TAL-BP agar, modified Oxford (MOX) agar, TAL-MOX agar, xylose lysine sodium desoxycholate (XLD) agar, TAL-XLD agar, Yersinia-selective (CIN) agar, and TAL-CIN agar. The TAL plates were prepared by pipetting 6 ml of selective agar into a BBL Rodac plate (65 by 15 mm). Selective agar was allowed to solidify, and then each plate was overlaid with 6 ml of TSA. Selective agar plates were prepared by pipetting 12 ml of agar into BBL Rodac plates and allowing the agar to solidify. Samples were taken at an indoor cattle facility at five separate locations with a BioScience SAS air-sampling instrument. For each plate, 60 liters of air was sampled. Three replications of the experiment were performed. The TAL method resulted in higher counts of microorganisms on all media tested. In addition, 175 isolates were selected randomly and identified in order to test the selectivity of TAL and the selective media for target organisms. The data obtained in this study show that the TAL resuscitation method is effective and necessary for the recovery of airborne organisms that may be injured. PMID:12233864

  12. Syneresis and delayed detachment in agar plates.

    PubMed

    Divoux, Thibaut; Mao, Bosi; Snabre, Patrick

    2015-05-14

    Biogels made of crosslinked polymers such as proteins or polysaccharides behave as porous soft solids and store large amounts of solvent. These gels undergo spontaneous aging, called syneresis, which consists of the shrinkage of the gel matrix and the progressive expulsion of solvent. As a result, a biogel originally casted in a container often loses contact with the container sidewalls, and the detachment time is difficult to anticipate a priori, since it may occur over variable time spans (from hours to days). Here we report on syneresis phenomena in agar plates, which consist of Petri dishes filled with a gel mainly composed of agar. Direct observations and speckle pattern correlation analysis allow us to rationalize the delayed detachment of the gel from the sidewall of the Petri dish. The detachment time t* is surprisingly not controlled by the mass loss as one would intuitively expect. Instead, t* is strongly correlated to the gel minimum thickness emin measured along the sidewall of the plate, and increases as a robust function of emin, independently of the prior mass-loss history. Time-resolved correlation spectroscopy atypically applied to such weakly diffusive media gives access to the local thinning rate of the gel. This technique also allows us to detect the gel micro-displacements that are triggered by water evaporation prior to the detachment, and even to anticipate the latter from a few hours. Our work provides observables to predict the detachment time of agar gels in dishes, and highlights the relevance of speckle pattern correlation analysis for the quantitative investigation of the syneresis dynamics in biopolymer gels. PMID:25812667

  13. Characteristic features and dye degrading capability of agar-agar gel immobilized manganese peroxidase.

    PubMed

    Bilal, Muhammad; Asgher, Muhammad; Shahid, Muhammad; Bhatti, Haq Nawaz

    2016-05-01

    Immobilization of enzymes has been regarded as an efficient approach to develop biocatalyst with improved activity and stability characteristics under reaction conditions. In the present study, purified manganese peroxidase (MnP) from Ganoderma lucidum IBL-05 was immobilized in agar-agar support using entrapment technique. Maximum immobilization yield was accomplished at 4.0% agar-agar gel. The immobilized MnP exhibited better resistance to changes in pH and temperature than the free enzyme, with optimal conditions being pH 6.0 and 50°C. The kinetic parameters Km and Kcat/Km for free and entrapped MnP were calculated to be 65.6mM and 6.99M(-1)s(-1), and 82mM and 8.15M(-1)s(-1), respectively. Thermo-stability was significantly improved after immobilization. After 120h, the insolubilized MnP retained its activity up to 71.9% and 60.3% at 30°C and 40°C, respectively. It showed activity until 10th cycle and retained 74.3% residual activity after 3th cycle. The effects of H2O2, ionic strength and potential inhibitors on activity of free and immobilized enzyme were investigated. Moreover, the decolorization of three structurally different dyes was monitored in order to assess the degrading capability of the entrapped MnP. The decolorization efficiencies for all the tested dyes were 78.6-84.7% after 12h. The studies concluded that the toxicity of dyes aqueous solutions was significantly reduced after treatment. The remarkable catalytic, thermo-stability and re-cycling features of the agar-agar immobilized MnP display a high potential for biotechnological applications. PMID:26854887

  14. Blue Note

    ScienceCinema

    Murray Gibson

    2010-01-08

    Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast."Blue" notes are very harmonic notes that are missing from the equal temperament scale.The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting.

  15. Blue Note

    SciTech Connect

    Murray Gibson

    2007-04-27

    Argonne's Murray Gibson is a physicist whose life's work includes finding patterns among atoms. The love of distinguishing patterns also drives Gibson as a musician and Blues enthusiast."Blue" notes are very harmonic notes that are missing from the equal temperament scale.The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting.

  16. Blue lesions.

    PubMed

    Longo, Caterina; Scope, Alon; Lallas, Aimilios; Zalaudek, Iris; Moscarella, Elvira; Gardini, Stefano; Argenziano, Giuseppe; Pellacani, Giovanni

    2013-10-01

    Blue color is found in a wide range of malignant and benign melanocytic and nonmelanocytic lesions and in lesions that result from penetration of exogenous materials, such as radiation or amalgam tattoo or traumatic penetration of particles. Discriminating between different diagnostic entities that display blue color relies on careful patient examination and lesion assessment. Dermoscopically, the extent, distribution, and patterns created by blue color can help diagnose lesions with specificity and differentiate between benign and malignant entities. This article provides an overview of the main diagnoses whereby blue color can be found, providing simple management rules for these lesions. PMID:24075551

  17. Biological treatment of textile dyes by agar-agar immobilized consortium in a packed bed reactor.

    PubMed

    Patel, Yogesh; Gupte, Akshaya

    2015-03-01

    The decolorization of Acid Maroon V was investigated using bacterial consortium EDPA containing Enterobacter dissolvens AGYP1 and Pseudomonas aeruginosa AGYP2 immobilized in different entrapment matrices. The consortium displayed 96% removal of dye (100 mg/l) within 6 h when immobilized in agar-agar. Under optimum concentrations of agar-agar (3.0% w/v) and cell biomass (0.9 g% w/v), the consortium displayed decolorization for 18 successive batches of Acid Maroon V and also decolorized 14 other different textile dyes. A packed bed reactor under batch mode showed 89% decolorization of dye after 56 repetitive cycles. Under continuous flow mode, maximum color removal was achieved with bed length of 36 cm, hydraulic retention time of 2.66 h, and dye concentration of 100 mg/l. Additionally, the reactor decolorized relatively higher concentrations (100-2000 mg/l) of dye. The synthetic dye wastewater containing five textile dyes was decolorized 92% with 62% COD reduction using an immobilized consortium. PMID:25842535

  18. Screening fungicides for use in fish culture: Evaluation of the agar plug transfer, cellophane transfer, and agar dilution methods

    USGS Publications Warehouse

    Bailey, Tom A.

    1983-01-01

    The reliability, reproducibility, and usefulness of three screening methods -- the cellophane transfer, the agar plug transfer, and the agar dilution -- to screen aquatic fungicides were evaluated. Achlya flagellata and Saprolegnia hypogyna were exposed to 1, 10, and 100 mg/L of malachite green to test each method. The cellophane transfer and agar plug transfer techniques had similar reliability and reproducibility in rating fungicidal activity, and were both superior to the agar dilution technique. The agar plug transfer and agar dilution techniques adequately projected in vivo activity of malachite green, but the cellophane transfer technique overestimated its activity. Overall, the agar plug transfer technique most accurately rated the activity of malachite green and was the easiest test to perform. It therefore appears to be the method of choice for testing aquatic fungicides.

  19. Poisoning with brown fly agaric, Amanita regalis.

    PubMed

    Elonen, E; Tarssanen, L; Härkönen, M

    1979-01-01

    Three patients ate different amounts of a common northern mushroom, brown fly agaric, Amanita regalis. All of them believed they had eaten delicious parasol mushrooms, Macrolepiota procera. The symptoms of poisoning began 1--2 hours after ingestion of the mushrooms. All the patients had marked gastrointestinal symptoms: nausea and heavy vomiting. Two had central nervous system manifestations and cholinergic symptoms: hallucinations, confusion, or loss of consciousness as well as copious salivation, or sweating. All patients recovered within 4--24 hours without any damage to liver, kidneys or central nervous system. It seems that cooking the mushrooms does not completely neutralize the toxic agents of Amanita regalis. The analysis of fried mushrooms shows that it may be possible to identify mushrooms reliably from the remains of a meal. PMID:760400

  20. Improving agar electrospinnability with choline-based deep eutectic solvents.

    PubMed

    Sousa, Ana M M; Souza, Hiléia K S; Uknalis, Joseph; Liu, Shih-Chuan; Gonçalves, Maria P; Liu, LinShu

    2015-09-01

    Very recently our group has produced novel agar-based fibers by an electrospinning technique using water as solvent and polyvinyl alcohol (PVA) as co-blending polymer. Here, we tested the deep eutectic solvent (DES), (2-hydroxyethyl)trimethylammonium chloride/urea prepared at 1:2 molar ratio, as an alternative solvent medium for agar electrospinning. The electrospun materials were collected with an ethanol bath adapted to a previous electrospinning set-up. One weight percent agar-in-DES showed improved viscoelasticity and hence, spinnability, when compared to 1 wt% agar-in-water and pure agar nanofibers were successfully electrospun if working above the temperature of sol-gel transition (∼80 °C). By changing the solvent medium we decreased the PVA concentration (5 wt% starting solution) and successfully produced composite fibers with high agar contents (50/50 agar/PVA). Best composite fibers were formed with the 50/50 and 30/70 agar/PVA solutions. These fibers were mechanically resistant, showed tailorable surface roughness and diverse size distributions, with most of the diameters falling in the sub-micron range. Both nano and micro forms of agar fibers (used separately or combined) may have potential for the design of new and highly functional agar-based materials. PMID:26116384

  1. Cost-effective nanoporous Agar-Agar polymer/Nickel powder composite particle for effective bio-products adsorption by expanded bed chromatography.

    PubMed

    Asgari, Setareh; Jahanshahi, Mohsen; Rahimpour, Ahmad

    2014-09-26

    In the present work a novel kind of dense nanoporous composite matrix for expanded bed application has been successfully first prepared with Nickel powder as a densifier and was covered with Agar-Agar layer as a skeleton, through the method of water-in-oil emulsification. Agar-Agar is a porous and inexpensive polymer. In order to fabricate cost-effective adsorbent with favorable qualities Agar-Agar polymer was used. Thereafter, the customized composite particle was modified by pseudo-affinity dye-ligand, Reactive Blue 4 (RB4), aimed at preparing a pseudo-affinity adsorbent (RB4-Agar-Ni) for bioprodut adsorption from aqueous solution. Bovine Serum Albumin (BSA) was selected as a model protein to investigate the adsorption behavior in batchwise and expanded bed chromatography, and the obtained results were evaluated with that of Streamline™ (Amersham-Pharmacia Biotech, Sweden). Spherical appearance and porous structure of composite particles were observed by the optical microscope (OM) and scanning electronic microscope (SEM). The results suggested that the matrices followed the logarithmic normal size distribution with the range of 65-300 μm and average diameter of 126.81-151.47 μm, proper wet density of 1.64-2.78 g/ml, water content of 62.74-34%, porosity of 98-90% and pore size of about 38-130 nm. For better comprehension of the impact of solid phase properties on the performance of the expanded bed, the expansion and hydrodynamic properties of a composite matrix with a series of densities was evaluated and estimated by the retention time distribution method (RTD) in an expanded bed and was compared with that of other matrices. According to obtained results the expansion factors under the same fluid velocity decreased by increasing the matrix density. Moreover, the axial dispersion coefficient (Dax) is the most appropriate parameter for evaluating the stability of expanded bed, on various operating conditions, such as different flow velocity, bed expansion degree, viscosity of the liquid phase and the density of adsorbent. It was observed that the application of matrix with high density was proper for high operation, fluid velocity, since the addition of densifier improves the rigidity of the matrix. Three momentous factors, pH, ionic strength and initial concentration of BSA were analyzed. The best results showed that the adsorption equilibrium isotherms seems to follow a typical Langmuir isotherm and also the maximum adsorption capacity (qm) of BSA on RB4-Agar-Ni (64.01 mg/ml adsorbent) was higher than that on RB4-Streamline commercial adsorbent (about 54 mg.ml adsorbent). Additionally kinetic adsorption processes were characterized by the pseudo-first-order and pseudo-second-order kinetics equations. The experimental data followed the pseudo-first-order kinetic equation. Also the breakthrough curves were investigated. It was found that dynamic binding capacity (DBC) decreased with increasing the flow rate and the values of DBC decreased from 21.08 to 11.15 mg/ml adsorbent when the density of composite beads increased from 1.64 to 2.78 g/ml. All results indicate that the prepared composite is promising for efficient bioproduct adsorption with good hydrodynamic characteristics, high stability and it is suitable for expanded bed usage as a cost-effective adsorbent. PMID:25152492

  2. Rapid fluorescence method for screening Salmonella spp. from enteric differential agars.

    PubMed

    Aguirre, P M; Cacho, J B; Folgueira, L; López, M; García, J; Velasco, A C

    1990-01-01

    Four hundred thirty-two lactose-negative colonies isolated from human feces on stool differential agar media were flooded with one drop of MUCAP Test reagent (Biolife Italiana S.r.I., Milan, Italy) and observed under a Wood lamp for the development of a blue fluorescence over or around the colony. On the basis of manual and automated conventional tests for the screening of Salmonella spp., the MUCAP Test yielded the following results: 79 true-positives, 314 true-negatives, 35 false-positives, and 4 false-negatives (sensitivity, 95%; specificity, 90%; positive predictive value, 69%; negative predictive value, 99%). The specificity of the test performed on colonies isolated on MacConkey agar (95%) was higher than that performed on colonies isolated on SS agar (88%; P less than 0.03). The MUCAP Test is an easy, rapid, and sensitive method for the screening of colonies suspected of being Salmonella spp., reducing the number of biochemical tests needed. PMID:2405010

  3. A novel chromogenic ester agar medium for detection of Salmonellae.

    PubMed

    Cooke, V M; Miles, R J; Price, R G; Richardson, A C

    1999-02-01

    A novel agar medium, chromogenic Salmonella esterase (CSE) agar, for the differentiation of salmonellae is described. The agar contains peptones and nutrient extracts together with the following (grams per liter unless otherwise specified): 4-[2-(4-octanoyloxy-3, 5-dimethoxyphenyl)-vinyl]-quinolinium-1-(propan-3-yl carboxylic acid) bromide (SLPA-octanoate; bromide form), 0.3223; lactose, 14. 65; trisodium citrate dihydrate, 0.5; Tween 20, 3.0; ethyl 4-dimethylaminobenzoate, 0.035% (wt/vol), novobiocin, 70 mg liter-1. The key component of the medium is SLPA-octanoate, a newly synthesized ester formed from a C8 fatty acid and a phenolic chromophore. In CSE agar, the ester is hydrolyzed by Salmonella spp. to yield a brightly colored phenol which remains tightly bound within colonies. After 24 h of incubation at 37 or 42 degreesC, colonies of typical Salmonella spp. were burgundy colored on a transparent yellow background, whereas non-Salmonella spp. were white, cream, yellow or transparent. CSE agar was evaluated by using a panel of strains including a high proportion of Salmonella and non-Salmonella strains giving atypical reactions on other differential agars. The sensitivity (93.1%) of CSE agar for non-typhi salmonellae compared favorably with those of Rambach (82. 8%), xylose-lysine-deoxycholate (XLD; 91.4%), Hektoen-enteric (89.7%), and SM ID (91.4%) agars. The specificity (93.9%) was also comparable to those of other Salmonella media (SM ID agar, 95.9%; Rambach agar, 91.8%; XLD agar, 91.8%; Hektoen-enteric agar, 87.8%). Strains of Citrobacter freundii and Proteus spp. giving false-positive reactions with other media gave a negative color reaction on CSE agar. CSE agar enabled the detection of >30 Salmonella serotypes, including agona, anatum, enteritidis, hadar, heidelberg, infantis, montevideo, thompson, typhimurium, and virchow, which accounted for 91.8% of the salmonella isolates recorded by the Public Health Laboratory Service (Colindale, London, England) for 1997. PMID:9925620

  4. A Novel Chromogenic Ester Agar Medium for Detection of Salmonellae

    PubMed Central

    Cooke, Venitia M.; Miles, R. J.; Price, R. G.; Richardson, A. C.

    1999-01-01

    A novel agar medium, chromogenic Salmonella esterase (CSE) agar, for the differentiation of salmonellae is described. The agar contains peptones and nutrient extracts together with the following (grams per liter unless otherwise specified): 4-[2-(4-octanoyloxy-3,5-dimethoxyphenyl)-vinyl]-quinolinium-1-(propan-3-yl carboxylic acid) bromide (SLPA-octanoate; bromide form), 0.3223; lactose, 14.65; trisodium citrate dihydrate, 0.5; Tween 20, 3.0; ethyl 4-dimethylaminobenzoate, 0.035% (wt/vol), novobiocin, 70 mg liter?1. The key component of the medium is SLPA-octanoate, a newly synthesized ester formed from a C8 fatty acid and a phenolic chromophore. In CSE agar, the ester is hydrolyzed by Salmonella spp. to yield a brightly colored phenol which remains tightly bound within colonies. After 24 h of incubation at 37 or 42C, colonies of typical Salmonella spp. were burgundy colored on a transparent yellow background, whereas non-Salmonella spp. were white, cream, yellow or transparent. CSE agar was evaluated by using a panel of strains including a high proportion of Salmonella and non-Salmonella strains giving atypical reactions on other differential agars. The sensitivity (93.1%) of CSE agar for non-typhi salmonellae compared favorably with those of Rambach (82.8%), xylose-lysine-deoxycholate (XLD; 91.4%), Hektoen-enteric (89.7%), and SM ID (91.4%) agars. The specificity (93.9%) was also comparable to those of other Salmonella media (SM ID agar, 95.9%; Rambach agar, 91.8%; XLD agar, 91.8%; Hektoen-enteric agar, 87.8%). Strains of Citrobacter freundii and Proteus spp. giving false-positive reactions with other media gave a negative color reaction on CSE agar. CSE agar enabled the detection of >30 Salmonella serotypes, including agona, anatum, enteritidis, hadar, heidelberg, infantis, montevideo, thompson, typhimurium, and virchow, which accounted for 91.8% of the salmonella isolates recorded by the Public Health Laboratory Service (Colindale, London, England) for 1997. PMID:9925620

  5. Selected elements in fly agaric Amanita muscaria.

    PubMed

    Falandysz, J; Kunito, T; Kubota, R; Lipka, K; Mazur, A; Falandysz, Justyna J; Tanabe, S

    2007-09-01

    Concentrations of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Cs, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Pb, Rb, Se, Sb, Sr, V, Tl and Zn have been determined in the whole fruiting bodies, as well as separately in caps and stalks, of fly agaric collected from three geographically distant sites in northern part of Poland. The elements were determined using ICP-MS, ICP-OES, HG-AAS and CV-AAS, respectively. For elements such as Al, Ba, Cr, Fe, Ga, Mo, Mn, Pb, Sb, Sr, Tl, and V concentrations were similar in the caps and stalks, respectively, and for K, Zn, Ag, Ca, Cd, Cu, Hg, Mg, Rb and Se were greater in the caps, while for Co, Cs and Na in the stalks. For Ag, Al, Ba, Ca, Cd, Co, Cr, Cs, Fe, Ga, Hg, Mn, Mo, Pb, Rb, Sb, Sr, Tl and V concentration in the caps showed spatial variations (P<0.05), while for Cu, K, Mg, Na, Se and Zn was independent of the site. The elements such as K with median or mean in the caps between 37,000 and 43,000 microg/g.dm and Mg with 920 and 1,100 microg/g dm were most abundant. Next, within median values range from approximately 100 to 500 microg/g dm were such as Ca, Fe and Al, and in descending order they followed by Rb (100-400 microg/g dm); V, Na, Zn (50-200 microg/g dm); Cu, Mn (10-50 microg/g dm); Cd (10-20 microg/g dm); Se (5 microg/g dm); Ba (<1-3); Cr, Ag, Pb, Sr (<1-2 microg/g dm); Cs, Co, Hg (<1-1 microg/g dm); Ga (<0.5), Sb, Mo and Tl (<0.1 microg/g dm). PMID:17849303

  6. Blue Water

    The Canadian Coast Guard Ship Louis S. St-Laurent has a mechanical system that creates bubbles that rise to the surface and push ice away from the ship's hull. It also happens to churn the water into an amazing shade of blue....

  7. Effect of water structure on gelation of agar in glycerol solutions and phase diagram of agar organogels.

    PubMed

    Boral, Shilpi; Bohidar, H B

    2012-06-21

    A comprehensive study of hydration of polyanionic agar molecules in its solution and gel phase in glycerol-water binary solvent is reported. Raman spectroscopy results predict differential water structure arrangement for glycerol-water binary solvent, 0.02% (w/v) agar in glycerol solution and 0.3% (w/v) agar organogel. The 3200 cm(-1) Raman band pertaining to ice-like structure of water was found to increase in gel phase alike in glycerol-water solvent while it decreased in agar solutions with increase in glycerol concentration. In contrast, the partially structured water corresponding to the component 3310 cm(-1) of Raman spectra increased in agar solution, and decreased in gel phase similar to glycerol-water solvent case. We have explained these observations based on a simple model where the available oxygen to hydrogen atom ratio in a given solvent-polymer system uniquely defines hydration in solution and gel phases. The gelation concentration was found to increase from 0.18 (for water) to 0.22% (w/v) (50% v/v glycerol solution) as the glycerol concentration was raised. Correspondingly, the gelation temperature, T(g), showed a decline from 40 to 20 °C, and the gel melting temperature, T(m), revealed a reduction from 81 to 65 °C in the same glycerol concentration regime. Two distinctive features are evident here: (i) presence of glycerol as a cosolvent does not favor the gelation of agar as compared to water and (ii) agar organogels are softer than their hydrogels. A unique 3D phase diagram for the agar organogel is proposed. Circular dichroism data confirmed that the agar molecules retained their biological activity in these solvents. Thus, it is shown that thermo-mechanical properties of these organogels could be systematically tuned and adapted as per application requirement. PMID:22657388

  8. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... containing an agar gel used to examine antigen-antibody reactions. In immunodiffusion, antibodies and antigens migrate toward each other through gel which originally contained neither of these reagents. As...

  9. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... containing an agar gel used to examine antigen-antibody reactions. In immunodiffusion, antibodies and antigens migrate toward each other through gel which originally contained neither of these reagents. As...

  10. Agar/collagen membrane as skin dressing for wounds.

    PubMed

    Bao, Lei; Yang, Wei; Mao, Xuan; Mou, Shansong; Tang, Shunqing

    2008-12-01

    Agar, a highly hydrophilic polymer, has a special gel property and favorable biocompatibility, but moderate intension strength in an aqueous condition and a low degradation rate. In order to tailor both properties of mechanical intension and degradation, type I collagen was composited with agar in a certain ratio by drying at 50 degrees C or by a freeze-dry process. Glutaraldehyde was chosen as a crosslinking agent, and the most favorable condition for crosslinking was that the weight ratio of agar to glutaraldehyde was 66.7 and the pH value about 5. Dynamic mechanical analysis results showed that the single agar membrane had a modulus value between 640 MPa and 1064 MPa, but it was between 340 MPa and 819 MPa after being composited with type I collagen. It was discovered under an optical microscope that the pores were interconnected in the composite scaffolds instead of the honeycomb-like pores in a single type I collagen scaffold or the laminated gaps in a single agar scaffold. The results of an acute toxicity test disclosed that the composites were not toxic to mice although the composites were crosslinked with a certain concentration of glutaraldehyde. The results of gross examinations showed that when the composite membranes or scaffolds were applied to a repair rabbit skin lesion, the composites had a good repair effect without infection, liquid exudation or visible scar in the lesion covered with them. But in the control group, the autologous skin showed necrosis and there were a lot of scar tissues in the lesion site. H&E staining results showed that the repair tissue was similar to the normal one and very few scaffolds or membranes were left without degradation after 2 or 3 weeks. In conclusion, it is proved that type I collagen increases the toughness of the agar membrane, and the agar/type I collagen composites are promising biomaterials as wound dressings for healing burns or ulcers. PMID:19029613

  11. Hyperspectral imaging for detecting pathogens grown on agar plates

    NASA Astrophysics Data System (ADS)

    Yoon, Seung Chul; Lawrence, Kurt C.; Siragusa, Gregory R.; Line, John E.; Park, Bosoon; Windham, William R.

    2007-09-01

    This paper is concerned with the development of a hyperspectral imaging technique for detecting and identifying one of the most common foodborne pathogens, Campylobacter. Direct plating using agars is an effective tool for laboratory tests and analyses of microorganisms. The morphology (size, growth pattern, color, etc.) of colonies grown on agar plates has been widely used to tentatively differentiate organisms. However, it is sometimes difficult to differentiate target organisms like Campylobacters from other contaminants grown together on the same agar plates. A hyperspectral imaging system operating at the visible and near infrared (VNIR) spectral region from 400 nm to 900 nm was set up to measure spectral signatures of 17 different Campylobacter and non-Campylobacter subspecies. Protocols for culturing, imaging samples and for calibrating measured data were developed. The VNIR spectral library of all 17 organisms commonly encountered in poultry was established from calibrated hyperspectral images. A classification algorithm was developed to locate and identify Campylobacters, non-Campylobacter contaminants, and background agars with 99.29% accuracy. This research has a potential to be expanded to detect other pathogens grown on agar media.

  12. Fly agaric (Amanita muscaria) poisoning, case report and review.

    PubMed

    Satora, Leszek; Pach, Dorota; Butryn, Beata; Hydzik, Piotr; Balicka-Slusarczyk, Barbara

    2005-06-01

    Gathering and eating mushrooms and other plants containing psychoactive substances has become increasingly popular among young people experimenting with drugs. Dried fly agaric Amanita muscaria fruiting bodies were eaten by five young persons (18-21 years of age) at a party in order to evoke hallucinations. Visual and auditory hallucinations occurred in four of them, whereas a 18-year-old girl lost consciousness. The following morning, she went to the Clinic of Toxicology. Due to the fact that not all the active substances present in the fly agaric have been identified, and some of them have an effect after a period of latency, the patient was admitted for several days of observation during which check-up examinations were performed. After four days without any problems, she was discharged. The poisoning regressed with no organ complications. The remaining persons who had eaten the fly agaric were free from any complaints. PMID:15904689

  13. Differentiation of Candida dubliniensis from Candida albicans on Pal's Agar

    PubMed Central

    Al Mosaid, Asmaa; Sullivan, Derek J.; Coleman, David C.

    2003-01-01

    Production of a hyphal fringe around colonies grown on Pal's agar (sunflower seed agar) at 30°C for 48 to 72 h provides a simple means of discriminating between isolates of C. dubliniensis and C. albicans with 100% accuracy. Of 128 C. dubliniensis isolates tested on this medium, all produced a hyphal fringe. In contrast, none of the 124 C. albicans isolates tested produced a hyphal fringe. Pal's medium has the added advantage of being prepared from inexpensive, readily available seeds. PMID:14532221

  14. Is blood agar an alternative to sabouraud dextrose agar for the isolation of fungi in patients with mycotic keratitis.

    PubMed

    Reddy, Ashok Kumar; Brahmaiah, Upputuri; Narayen, Nitesh; Reddy, Ravi Kumar; Reddy, Rupak Kumar; Chitta, Meghraj; Prasad, Srinivas; Swarup, Rishi; Mohiuddin, Syed Maaz; Reddy, Madhukar; Aasuri, Murali K; Murthy, B S R; Bhide, Milind; Ahmed, Sajid

    2013-06-01

    To compare the blood agar (BA), sabouraud dextrose agar (SDA) and chocolate agar (CA) for the isolation of fungi in patients with mycotic keratitis. Corneal Scrapings of 229 patients with clinically diagnosed microbial keratitis were inoculated on BA, SDA, CA. The culture media were evaluated for the rate and time taken for the fungal growth. Seventy six of 229 patients had fungal keratitis. Fungus grew on BA in 60/76(78.9 %), on SDA in 76/76 (100 %), on CA in 40/76(52.6 %) patients. The fungi which grew on BA (60/76) also grown on SDA at the same time. The colony morphologies of different fungi were better on SDA than BA/CA. Among the different culture media, SDA is essential for the isolation fungi in patients with mycotic keratitis. PMID:23196788

  15. Hyperspectral Imaging for Detecting Pathogens Grown on Agar Plates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper is concerned with the development of a hyperspectral imaging technique for detecting and identifying one of the most common foodborne pathogens, Campylobacter. Direct plating using agars is an effective tool for laboratory tests and analyses of microorganisms. The morphology (size, growth...

  16. Internal structure and thermo-viscoelastic properties of agar ionogels.

    PubMed

    Sharma, Anshu; Rawat, Kamla; Solanki, Pratima R; Aswal, V K; Kohlbrecher, J; Bohidar, H B

    2015-12-10

    Ionic liquids (IL) can alter the physical properties of agar hydrogels. Rheology studies show that gels with wide range of storage moduli (gel strength) G0 values ranging from 1 to 20 KPa could be made in imidazolium based IL solutions where the IL concentration may not exceed 5% (w/v). Gelation and gel melting temperatures (tgel and Tm) could be altered by as much as ≈ 10 °C. Small angle neutron scattering studies revealed the presence of fibre bundles of agar double helices having typical length of 120 nm that increased to ≈ 180 nm under favorable conditions. These structures gain flexibility from the cladding of the agar bundles by IL molecules which in turn caused partial charge neutralization of its surface. Raman spectroscopy revealed differential hydration of these bundles. It was found that IL molecules with longer alkyl chain (more hydrophobic) altered the gel homogeneity, and changed its thermal and mechanical properties significantly. Therefore, customization of agar hydrogels in green solvent medium (IL solutions) widens the scope of its application potential that may include sensing. PMID:26428165

  17. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  18. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  19. 21 CFR 866.4600 - Ouchterlony agar plate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ouchterlony agar plate. 866.4600 Section 866.4600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents §...

  20. Improving agar electrospinnability with choline-based deep eutectic solvents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One percent agar (% wt) was dissolved in the deep eutectic solvent (DES), (2-hydroxyethyl) trimethylammonium chloride/urea at a 1:2 molar ratio, and successfully electrospun into nanofibers. An existing electrospinning set-up, operated at 50 deg C, was adapted for use with an ethanol bath to collect...

  1. Growth kinetics of three species of Tetrahymena on solid agar

    SciTech Connect

    Dobra, K.W.; McArdle, E.W.; Ehret, C.F.

    1980-01-01

    A nutrient-agar method without liquid overlay has been developed for cultivation of ciliates. Three species of Tetrahymena-T. pyriformis strain W, T. rostrata strain UNI, and T. vorax strain V/sub 2/S, representing the 3 main groups of Tetrahymena species, were used; however the method should apply to other ciliates. Growth on the surface of the agar was facilitated by an optimal surface-to-volume ratio yielding a high density of ciliates and short generation times. At the highest density achieved, the cells became irregularly hexagonal and formed a monolayer tissue on the agar. Ciliates grown on agar were like those in liquid culture, typical oral ciliature, food-vacuole formation, and typical cortical patterns being retained. Advantages of this method include high cell density, easy recovery, and optimal O/sub 2/ supply. The organisms can also be cultivated on the surface of sterile cellulose-nitrate filters, facilitating in situ fixation and staining as well as transfer into different media by transfer of filters with cells, without prior centrifugation and resuspension.

  2. Use of potato flakes agar in clinical mycology.

    PubMed

    Rinaldi, M G

    1982-06-01

    A formulation comprised of commercially available potato flakes, glucose, and agar provides a medium which is inexpensive, is easily prepared, and is particularly useful for the identification of mold fungi encountered in the clinical mycology laboratory. The inclusion of appropriate antimicrobial agents results in a selective medium effective in the isolation and identification of medically important fungi. PMID:7050152

  3. Recovery of Sublethally Injured Bacteria Using Selective Agar Overlays.

    ERIC Educational Resources Information Center

    McKillip, John L.

    2001-01-01

    This experiment subjects bacteria in a food sample and an environmental sample to conditions of sublethal stress in order to assess the effectiveness of the agar overlay method to recover sublethally injured cells compared to direct plating onto the appropriate selective medium. (SAH)

  4. The Blue Bottle Revisited.

    ERIC Educational Resources Information Center

    Vandaveer, Walter R., IV; Mosher, Mel

    1997-01-01

    Presents a modification of the classic Blue Bottle demonstration that involves the alkaline glucose reduction of methylene blue. Uses other indicators in the classic Blue Bottle to produce a rainbow of colors. (JRH)

  5. Thermal-induced ageing of agar solutions: impact on the structural and mechanical properties of agar gels

    NASA Astrophysics Data System (ADS)

    Mao, Bosi; Bentaleb, Ahmed; Louerat, Frédéric; Divoux, Thibaut; Snabre, Patrick

    Numerous hydrogels are prepared by cooling down to ambient temperature, aqueous polymer solutions brought to a boil. Although the incubation time of the polymer solution at such a high temperature could be used as a tuning parameter, its impact on the subsequent gelation has been poorly investigated. Here we study the effect of prolonged heating at 80°C on a 1.5% wt solution of agar, a natural polysaccharide. The incubation time is varied from a few hours up to five days. We show that the agar sol. continuously degrades as the result of both the hydrolysis and the intermolecular oxidation of the polymer chains. Furthermore, electronic microscopy and X-ray diffraction experiments reveal that gels formed from older agar sols display an increasingly coarser microstructure composed of micron-sized aggregated pieces of polysaccharides, in contrast with the fibrous-like structure of gels made from fresh sols. Along with structural changes prolonged incubation time leads to weaker gels of lower shear elastic modulus. Finally, macro-indentation experiments coupled to direct visualization show that increasing the incubation time of the agar sol. decreases the yield strain of the gel by a factor of three, while the rupture scenario turns continuously from brittle to ductile-like. Acknowledging funding from BioMérieux & CNRS.

  6. Development of a selective agar plate for the detection of Campylobacter spp. in fresh produce.

    PubMed

    Yoo, Jin-Hee; Choi, Na-Young; Bae, Young-Min; Lee, Jung-Su; Lee, Sun-Young

    2014-10-17

    This study was conducted to develop a selective medium for the detection of Campylobacter spp. in fresh produce. Campylobacter spp. (n=4), non-Campylobacter (showing positive results on Campylobacter selective agar) strains (n=49) isolated from fresh produce, indicator bacteria (n=13), and spoilage bacteria isolated from fresh produce (n=15) were plated on four Campylobacter selective media. Bolton agar and modified charcoal cefoperazone deoxycholate agar (mCCDA) exhibited higher sensitivity for Campylobacter spp. than did Preston agar and Hunt agar, although certain non-Campylobacter strains isolated from fresh produce by using a selective agar isolation method, were still able to grow on Bolton agar and mCCDA. To inhibit the growth of non-Campylobacter strains, Bolton agar and mCCDA were supplemented with 5 antibiotics (rifampicin, polymyxin B, sodium metabisulfite, sodium pyruvate, ferrous sulfate) and the growth of Campylobacter spp. (n=7) and non-Campylobacter strains (n=44) was evaluated. Although Bolton agar supplemented with rifampicin (BR agar) exhibited a higher selectivity for Campylobacter spp. than did mCCDA supplemented with antibiotics, certain non-Campylobacter strains were still able to grow on BR agar (18.8%). When BR agar with various concentrations of sulfamethoxazole-trimethoprim were tested with Campylobacter spp. (n=8) and non-Campylobacter (n=7), sulfamethoxazole-trimethoprim was inhibitory against 3 of 7 non-Campylobacter strains. Finally, we validated the use of BR agar containing 50mg/L sulfamethoxazole (BRS agar) or 0.5mg/L ciprofloxacin (BRCS agar) and other selective agars for the detection of Campylobacter spp. in chicken and fresh produce. All chicken samples were positive for Campylobacter spp. when tested on mCCDA, BR agar, and BRS agar. In fresh produce samples, BRS agar exhibited the highest selectivity for Campylobacter spp., demonstrating its suitability for the detection of Campylobacter spp. in fresh produce. PMID:25126968

  7. Comparison of chromogenic Biolog Rainbow agar Shigella/Aeromonas with xylose lysine desoxycholate agar for isolation and detection of Shigella spp. from foods.

    PubMed

    Zhang, Guodong; Lampel, Keith A

    2010-08-01

    Shigella outbreaks are widely reported throughout the world. However, it remains a challenge to isolate Shigella spp. from foods by using conventional microbiological media. The main objective of this study was to determine the effectiveness of a novel chromogenic medium, Rainbow agar Shigella/Aeromonas (Rainbow agar), for the isolation and detection of Shigella spp. in foods. All four Shigella species, S. sonnei, S. flexneri, S. dysenteriae, and S. boydii, were studied. Rainbow agar was compared with tryptic soy agar, xylose lysine desoxycholate agar (XLD), and Salmonella Shigella agar (SSA) for enumeration of Shigella spp. in pure culture. This chromogenic agar and XLD were also used to isolate Shigella spp. in artificially contaminated foods (4.8 log CFU/g of food), including lettuce, parsley, cilantro, spinach, potato salad, and shrimp. The inhibitory effect on Shigella growth by Rainbow agar was between that of XLD and SSA. All vegetables studied showed a moderately high background microflora on XLD and Rainbow agar. With artificially inoculated produce, Rainbow agar recovered about 1 to 2 log CFU more S. sonnei, S. dysenteriae, and S. boydii per g of food than did XLD. For potato salad and shrimp, which had low background microflora on Rainbow agar, Rainbow agar was slightly better in recovering Shigella spp. than XLD was in most cases. However, we found that the addition of streptomycin (6.25 mg/liter) to Rainbow agar could facilitate the isolation of Shigella in vegetables tested. In conclusion, Rainbow agar was a much more effective medium than was XLD for the isolation of Shigella spp. from foods. PMID:20819355

  8. Identification of Actinomyces israelii and Actinomyces naeslundii by Fluorescent-Antibody and Agar-Gel Diffusion Techniques1

    PubMed Central

    Lambert, Frank W.; Brown, June M.; Georg, Lucille K.

    1967-01-01

    This study was an attempt to develop a fluorescent-antibody (FA) test to differentiate Actinomyces israelii and A. naeslundii as an aid in their laboratory identification. Two strains of A. israelii (X522 and A601) and two strains of A. naeslundii (X454 and X600), which had received intensive study by several investigators, were used for the immunization of rabbits. Working titers, based on tests with antigens prepared from the homologous strains and from well-established heterologous strains, were determined for each labeled antibody preparation. These conjugates and their normal serum control conjugates were used separately to stain 85 cultures of Actinomyes species and 23 strains of other species that might be confused with them. Acetone-precipitated soluble antigens from these same strains were tested with different antisera in the agar-gel diffusion test. Results showed that A. israelii (X522 and A601) and A. naeslundii (X454 and X600) labeled antiglobulins, when used at their working titers, stained most strains of their homologous species. Agar-gel diffusion results showed general agreement with those of the FA tests. The two tests appear to be equal in sensitivity, but the FA test is more specific, since several cross-reactions were noted with the agar-gel diffusion test whereas no cross-reactions were obtained with the FA reagents. Agar-gel and FA studies suggest that at least two serotypes of A. israelii may be associated with human disease. Although the majority of strains tested in this study appear to belong to a common serotype, “serotype 1,” two strains of an apparent second serotype, “serotype 2,” were encountered. FA staining of tissue impression smears from experimentally infected mice was successful when a counterstain, Evans Blue dye, was used. PMID:4964473

  9. Detection of bacterioplankton in immersed cadavers using selective agar plates.

    PubMed

    Kakizaki, Eiji; Kozawa, Shuji; Tashiro, Noriko; Sakai, Masahiro; Yukawa, Nobuhiro

    2009-04-01

    We measured bacterioplankton in blood from cadavers retrieved from the sea (n=12), near estuaries (n=4), rivers (fresh water, n=8) and from bathtubs (n=4) as well as from non-drowned victims (n=10) discovered near aquatic environments. Blood from 11 victims drowned in seawater developed bioluminescent and/or blue colonies (oxidase test positive) on selective media containing 2-4% NaCl. Homology analyses of the 16S rRNA gene showed that all of them were marine bacteria (genera: Photobacterium, Vibrio, Shewanella, Psychrobacter). Blood from all victims drowned in rivers generated blue colonies on plates containing 3%, but not 4% NaCl. Homology analyses showed that the blue colonies were generated from bacteria that inhabit fresh water (Aeromonas). None of the blood samples from victims that drowned in bathtubs generated bioluminescent and blue colonies. However, all cadavers contained bacteria that produced unstained colonies (Staphylococcus, Bacillus, Enterobacter, Escherichia, etc.). Among non-drowned victims, blood from two gave rise to blue colonies on plates containing < or =3% NaCl (Pseudomonas). Of the cadavers found near estuaries, bioluminescent and blue colonies developed from two of them on media containing 2-4% NaCl (Photobacterium, Vibrio, Listonella), but not from two others on plates containing 4% NaCl (at < or =3%; blue colonies, Aeromonas; unstained colonies, Citrobacter, Vagococcus, Proteus, Enterobacter). These results suggested that the presence of numerous bacterioplankton in immersed cadavers could support a conclusion of death by drowning. PMID:19261520

  10. [Technological aspects of agar-hydrocolloid impression materials].

    PubMed

    Davidson, C L; Bekke-Hoekstra, I S

    1979-01-01

    Physical properties with clinical relevance has been tested on a number of agar hydrocolloid impression materials For 1 hour an almost perfect dimensional stability can be maintained when the impression is stored in water. Elasticity and strength are poor. Only the use of much bulk material may prevent damage during manipulation of the gel. The detail reproduceability meets all standards. A good compatibility with dental stone subsequently allows sharp details in the model. PMID:293792

  11. Modeling development of inhibition zones in an agar diffusion bioassay

    PubMed Central

    Chandrasekar, Vaishnavi; Knabel, Stephen J; Anantheswaran, Ramaswamy C

    2015-01-01

    A two-temperature agar diffusion bioassay is commonly used to quantify the concentration of nisin using Micrococcus luteus as the indicator microorganism. A finite element computational model based on Fick's second law of diffusion was used to predict the radius of the inhibition zone in this diffusion bioassay. The model developed was used to calculate nisin concentration profiles as a function of time and position within the agar. The minimum inhibitory concentration (MIC) of nisin against M. luteus was determined experimentally. The critical time (Tc) for growth of M. luteus within the agar diffusion bioassay was experimentally determined using incubation studies with nisin. The radius of the inhibition zone was predicted from the computational model as the location where the predicted nisin concentration at Tc was equal to MIC. The MIC was experimentally determined to be 0.156 μg mL−1, and Tc was determined to be 7 h. Good agreement (R2 = 0.984) was obtained between model-predicted and experimentally determined inhibition zone radii. PMID:26405525

  12. Modeling development of inhibition zones in an agar diffusion bioassay.

    PubMed

    Chandrasekar, Vaishnavi; Knabel, Stephen J; Anantheswaran, Ramaswamy C

    2015-09-01

    A two-temperature agar diffusion bioassay is commonly used to quantify the concentration of nisin using Micrococcus luteus as the indicator microorganism. A finite element computational model based on Fick's second law of diffusion was used to predict the radius of the inhibition zone in this diffusion bioassay. The model developed was used to calculate nisin concentration profiles as a function of time and position within the agar. The minimum inhibitory concentration (MIC) of nisin against M. luteus was determined experimentally. The critical time (T c) for growth of M. luteus within the agar diffusion bioassay was experimentally determined using incubation studies with nisin. The radius of the inhibition zone was predicted from the computational model as the location where the predicted nisin concentration at T c was equal to MIC. The MIC was experimentally determined to be 0.156 μg mL(-1), and T c was determined to be 7 h. Good agreement (R (2) = 0.984) was obtained between model-predicted and experimentally determined inhibition zone radii. PMID:26405525

  13. Electrospinning of agar/PVA aqueous solutions and its relation with rheological properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, we report the successful fabrication of agar-based nanofibers by an electrospinning technique using water as the solvent media. A tubeless spinneret was attached inside the electrospinning chamber, operated at 50 deg C, to avoid agar gelation. Pure agar solution 1% (w/w) showed inadequ...

  14. Agar-Gel Precipitin-Inhibition Test for Coccidioidomycosis

    PubMed Central

    Ray, John G.; Converse, John L.

    1967-01-01

    In this study of saprophytic and parasitic growth-phase extracts of Coccidioides immitis, an antigen from the spherule culture supernatant fluid detected a specific antibody in heretofore serologically negative suspect coccidioidomycosis human sera when diffused in agar-gel. This antigen-antibody reaction occurred also in some of the serologically positive human coccidioidomycosis sera. This study indicates that this antigen-antibody reaction should be utilized as a possible routine serological test for complete serodiagnosis. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:4964065

  15. Greening the Blue Bottle.

    ERIC Educational Resources Information Center

    Wellman, Whitney E.; Noble, Mark E.

    2003-01-01

    Compares the revised Blue Bottle formulation to the classical Blue Bottle. Indicates that the revised formulation gives a somewhat bluer solution, but initially slower reduction when compared to the classical formulation. (Author/KHR)

  16. Blue nightshade poisoning

    MedlinePlus

    ... when someone eats parts of the blue nightshade plant. This article is for information only. DO NOT ... is found in the blue nightshade ( Solanum dulcamara ) plant, especially in the fruit and leaves.

  17. Methylene blue test

    MedlinePlus

    The methylene blue test is a test to determine the type of methemoglobinemia , a blood disorder. ... tourniquet are removed. A dark green powder called methylene blue goes through the tube into your vein. The ...

  18. The Blue Water

    ERIC Educational Resources Information Center

    Berger, J. Joel

    1973-01-01

    Describes some of the advantages of an elementary science activity in which students discover that blowing through a straw into a bromthymol blue solution changes the color to yellow. Directions are provided for preparing the bromthymol blue solution. (JR)

  19. Comparison of Fecal Coliform Agar and Violet Red Bile Lactose Agar for Fecal Coliform Enumeration in Foods

    PubMed Central

    Leclercq, A.; Wanegue, C.; Baylac, P.

    2002-01-01

    A 24-h direct plating method for fecal coliform enumeration with a resuscitation step (preincubation for 2 h at 37 ± 1°C and transfer to 44 ± 1°C for 22 h) using fecal coliform agar (FCA) was compared with the 24-h standardized violet red bile lactose agar (VRBL) method. FCA and VRBL have equivalent specificities and sensitivities, except for lactose-positive non-fecal coliforms such as Hafnia alvei, which could form typical colonies on FCA and VRBL. Recovery of cold-stressed Escherichia coli in mashed potatoes on FCA was about 1 log unit lower than that with VRBL. When the FCA method was compared with standard VRBL for enumeration of fecal coliforms, based on counting carried out on 170 different food samples, results were not significantly different (P > 0.05). Based on 203 typical identified colonies selected as found on VRBL and FCA, the latter medium appears to allow the enumeration of more true fecal coliforms and has higher performance in certain ways (specificity, sensitivity, and negative and positive predictive values) than VRBL. Most colonies clearly identified on both media were E. coli and H. alvei, a non-fecal coliform. Therefore, the replacement of fecal coliform enumeration by E. coli enumeration to estimate food sanitary quality should be recommended. PMID:11916678

  20. Comparison between agar and methylcellulose cultures of human leukemic cells.

    PubMed

    Kubota, K; Preisler, H D; Sagawa, K; Minowada, J

    1981-08-01

    A comparison was made between the agar and methylcellulose culture systems with respect to their ability to support the clonal growth of leukemic cells obtained from patients with acute myeloblastic leukemia, acute lymphoblastic leukemia, and chronic myelogenous leukemia in blastic crisis. The number of clusters and/or colonies formed and the morphology of the cells within them varied from patient to patient. Nevertheless, no significant difference between the two culture systems within given leukemic specimens was found. No significant differences were noted among three different conditioned media used as sources of colony-stimulating activity. Most of the cells within clusters and colonies were identified to be immature members of granulocyte-macrophage series or to be indistinguishable from the preculture leukemic blast cells by morphological and cell surface marker studies. Cells from myeloid crisis in chronic myelogenous leukemia grew well in the cultures, but cells from lymphoid crisis did not proliferate. PMID:6941851

  1. Value of the K+ salt of carageenan as an agar substitute in routine bacteriological media.

    PubMed Central

    Lines, A D

    1977-01-01

    The K+ salt of carageenan has no distinct advantages as a gelling agent, but it compared favorably with agar in most of the media tested. The difficulty involved in the preparation of blood plates and the results obtained with this medium prohibit its complete acceptance as a substitute for agar in routine solid media. However, it could be a suitable substitute for agar in all other routine bacteriological media. PMID:596869

  2. Effect of Different Commerical Agar Preparations on the Inhibitory Activities of Phenols

    PubMed Central

    Sands, J. G.; Bennett, E. O.

    1966-01-01

    The minimal inhibitory concentrations of 11 phenolic inhibitors were compared in five commercial agars and in nutrient broth. It was found that the brand of agar affected the end point obtained for a particular inhibitor, and that the degree of antagonism varied with each compound studied. The results indicate that there are at least two deleterious factors present in agar, one of which is water-soluble and one which is not. The major portion of the total antagonism was due to the water-soluble factor, which could be removed by washing the agar in warm distilled water prior to use in the test medium. PMID:5959856

  3. Residual Agar Determination in Bacterial Spores by Electrospray Ionization Mass Spectrometry

    SciTech Connect

    Wahl, Karen L.; Colburn, Heather A.; Wunschel, David S.; Petersen, Catherine E.; Jarman, Kristin H.; Valentine, Nancy B.

    2010-02-15

    Presented here is an analytical method to detect residual agar from a bacterial spore sample as an indication of culturing on an agar plate. This method is based on the resolubilization of agar polysaccharide from a bacterial spore sample, enzymatic digestion, followed by electrospray ionization tandem mass spectrometry (ESI-MSn) analysis for detection of a specific agar fragment ion. A range of Bacillus species and strains were selected to demonstrate the effectiveness of this approach. The characteristic agar fragment ion was detected in the spores grown on agar that were washed from 1 to 5 times, irradiated or non-irradiated and not in the spores grown in broth. A sample containing approximately 108 spores is currently needed for confident detection of residual agar from culture on agar plates in the presence of bacterial spores with a limit of detection of approximately 1 ppm agar spiked into a broth-grown spore sample. The results of a proficiency test with 42 blinded samples are presented demonstrating the utility of this method with no false positives and only 3 false negatives for samples that were below the detection level of the method as documented.

  4. Effect of agar concentration on the matric potential of glycerol agar media and the germination and growth of xerophilic and non-xerophilic fungi.

    PubMed

    Huang, Yang; Chapman, Belinda; Wilson, Mark; Hocking, Ailsa D

    2009-07-31

    The concept of water activity (a(w)) does not differentiate between water status resulting from the interaction of water with solutes, and that from interaction of water with matrices, which is termed matric potential (psi(m)). This study reports the effect of agar concentration (1.5, 3.0, 4.5, 6.0, and 7.5%, w/w) on matric potential of glycerol agar media (GA) and the germination and growth of xerophilic fungi (Eurotium herbariorum and E. rubrum) and non-xerophilic fungi (Aspergillus niger, A. flavus, and Penicillium roqueforti) on GA with or without sorbic acid (0.1-0.4%, w/w) at 0.90 a(w) and 0.95 a(w). The matric potential of GA decreased when the agar concentration increased from 1.5 to 7.5%. When the agar concentration increased at each a(w), the radial growth rate of the xerophilic fungi generally increased but the biomass density (biomass per unit area) decreased, whereas the radial growth rate of the non-xerophilic fungi generally decreased but the biomass density was unchanged. In the absence of sorbic acid, the time to germination of each species was similar for all agar concentrations. In the presence of sorbic acid, the time to germination of some species was significantly longer at higher agar concentrations (4.5%-7.5%) than 1.5% agar. This study demonstrated the inhibition effect on germination and growth of non-xerophilic fungi and xerophilic fungi by decreased matric potential resulting from increased agar concentrations, and the different responses of non-xerophilic fungi and xerophilic fungi to water stress from solutes and matrices. The concept of matric potential may be useful in food microbiology to provide a better understanding of fungal growth in complex food matrices. PMID:19520449

  5. Glucose-sucrose-potassium tellurite-bacitracin agar, an alternative to mitis salivarius-bacitracin agar for enumeration of Streptococcus mutans.

    PubMed Central

    Tanzer, J M; Börjesson, A C; Laskowski, L; Kurasz, A B; Testa, M

    1984-01-01

    An agar medium for selective recovery and enumeration of Streptococcus mutans was developed as an alternative to mitis salivarius-bacitracin (MSB) agar. Combinations of dyes, antibiotics, and tellurite were added to a nonselective medium which, because of its sucrose content, allowed easy recognition of S. mutans colonies. Candle jar incubation for 2 days, by comparison with anaerobic incubation, reduced background flora but did not diminish S. mutans recoveries from clinical samples. Quantitative comparisons were made of the simultaneous recoveries of a number of authentic S. mutans serotype representatives and fresh clinical isolates, using various glucose-sucrose-potassium tellurite-bacitracin (GSTB) formulations and mitis salivarius, MSB, and blood agars. Mitis salivarius counts were not detectably different from blood counts, but counts on MSB were distinctly lower. A formulation of the new medium containing 5% glucose 5% sucrose, 0.001% potassium tellurite, 0.3 U of bacitracin per ml (hence GSTB), and 2% agar gave recoveries nearly equal to those on mitis salivarius agar and much greater than those on MSB. The medium yielded readily recognized S. mutans colonies and facilitated detection of intracellular polysaccharide formers upon flooding with I2 reagent. Freshly isolated serotype c, E, and f colonies could often be distinguished from serotype d and g colonies, a distinction made reliable by testing for intracellular polysaccharide. A study of 300 salivary samples revealed GSTB to give significantly higher recoveries than MSB. About 72% of all samples were substantially underestimated for S. mutans with MSB, and 6.7% of samples were falsely negative for S. mutans with MSB. Recovery of background flora on GSTB was as low or lower than on MSB, and both types of agar could be stored for at least 9 weeks without notable change of selectivity. Thus, GSTB agar appears to be simple and reliable to use and requires no anaerobic incubation. Caution is voiced about interpretation of data previously reported which evaluated S. mutans on MSB agar. Images PMID:6490852

  6. Glucose-sucrose-potassium tellurite-bacitracin agar, an alternative to mitis salivarius-bacitracin agar for enumeration of Streptococcus mutans.

    PubMed

    Tanzer, J M; Börjesson, A C; Laskowski, L; Kurasz, A B; Testa, M

    1984-10-01

    An agar medium for selective recovery and enumeration of Streptococcus mutans was developed as an alternative to mitis salivarius-bacitracin (MSB) agar. Combinations of dyes, antibiotics, and tellurite were added to a nonselective medium which, because of its sucrose content, allowed easy recognition of S. mutans colonies. Candle jar incubation for 2 days, by comparison with anaerobic incubation, reduced background flora but did not diminish S. mutans recoveries from clinical samples. Quantitative comparisons were made of the simultaneous recoveries of a number of authentic S. mutans serotype representatives and fresh clinical isolates, using various glucose-sucrose-potassium tellurite-bacitracin (GSTB) formulations and mitis salivarius, MSB, and blood agars. Mitis salivarius counts were not detectably different from blood counts, but counts on MSB were distinctly lower. A formulation of the new medium containing 5% glucose 5% sucrose, 0.001% potassium tellurite, 0.3 U of bacitracin per ml (hence GSTB), and 2% agar gave recoveries nearly equal to those on mitis salivarius agar and much greater than those on MSB. The medium yielded readily recognized S. mutans colonies and facilitated detection of intracellular polysaccharide formers upon flooding with I2 reagent. Freshly isolated serotype c, E, and f colonies could often be distinguished from serotype d and g colonies, a distinction made reliable by testing for intracellular polysaccharide. A study of 300 salivary samples revealed GSTB to give significantly higher recoveries than MSB. About 72% of all samples were substantially underestimated for S. mutans with MSB, and 6.7% of samples were falsely negative for S. mutans with MSB. Recovery of background flora on GSTB was as low or lower than on MSB, and both types of agar could be stored for at least 9 weeks without notable change of selectivity. Thus, GSTB agar appears to be simple and reliable to use and requires no anaerobic incubation. Caution is voiced about interpretation of data previously reported which evaluated S. mutans on MSB agar. PMID:6490852

  7. Blue-green algae

    MedlinePlus

    ... Lac Klamath, Anabaena, Aphanizomenon flos-aquae, Arthrospira maxima, Arthrospira platensis, BGA, Blue Green Algae, Blue-Green Micro-Algae, Cyanobacteria, Cyanobactérie, Cyanophycée, Dihe, Espirulina, Hawaiian Spirulina, Klamath, Klamath Lake Algae, Lyngbya wollei, Microcystis aeruginosa, ...

  8. Blue Willow Story Plates

    ERIC Educational Resources Information Center

    Fontes, Kris

    2009-01-01

    In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.

  9. FROM BLUE JEANS TO BLUE GENES

    PubMed Central

    Boon, Laurence M.; Vikkula, Miikka

    2010-01-01

    Cutaneous venous anomalies are common. They are blue in color and vary in size, number and location, and account for the majority of consultations at specialized interdisciplinary clinics for vascular anomalies. Venous lesions are clinically important as they cause pain, dysfunction, destruction of adjacent tissues and esthetic concern. Only resection and sclerotherapy are helpful, although not always curative. Understanding etiopathogenesis could help design animal models and develop novel therapeutic approaches. Dr Mulliken envisioned a project to uncover the genetic basis of an inherited form of venous malformation in a large New England family. Recruitment of two young fellows resulted in a collaborative project that unraveled the searched-for-gene and its mutation. This was an opening for a new era in the field of vascular anomalies. Two blue genes mutations were discovered, which account for the majority, if not all, of the inherited forms of venous anomalies, but other genes as well, for rheologically diverse lesions. Differential diagnosis and management has improved, and animal models are being made. This was achieved thanks to Dr Mulliken, who inspired two young investigators in blue jeans to find two blue genes. PMID:19190503

  10. Evaluation of fluorogenic TSC agar for recovering Clostridium perfringens in groundwater samples.

    PubMed

    Araujo, M; Sueiro, R A; Gmez, M J; Garrido, M J

    2001-01-01

    Clostridium perfringens is widely recognised as a reliable water pollution indicator. Since several media can be employed for the membrane filtration enumeration of this microorganism, the main aim of this work was to investigate the ability of fluorocult-supplemented TSC-agar (Merck) for recovering Cl. perfringens from public springs used for direct human consumption. Cl. perfringens recovery was also performed on mCP agar (Cultimed) according to Directive 98/83 as well as on TSC-Agar (Merck), TSN-Agar (Merck) and SPS-Agar (BBL) media. Variance analysis of data obtained showed no statistically significant differences in the counts obtained among all media employed in this work. However, the Cl. perfringens recovery efficiencies with TSC and fluorogenic TSC agars were significantly greater (P = < 0.05) than the corresponding values of mCP and TSN media. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that fluorogenic TSC agar was the most specific medium for Cl. perfringens recovery in groundwater samples (85.3% of typical colonies and 82.8% of atypical colonies confirmed). In summary, the membrane filtration technique with fluorogenic TSC agar showed the best performance characteristics of all the media tested as judged by their recovery efficiency and specificity in these water samples. PMID:11464756

  11. Physicochemical and morphological properties of plasticized poly(vinyl alcohol)-agar biodegradable films.

    PubMed

    Madera-Santana, T J; Freile-Pelegrín, Y; Azamar-Barrios, J A

    2014-08-01

    The effects of the addition of glycerol (GLY) on the physicochemical and morphological properties of poly(vinyl alcohol) (PVA)-agar films were reported. PVA-agar films were prepared by solution cast method, and the addition of GLY in PVA-agar films altered the optical properties, resulting in a decrease in opacity values and in the color difference (ΔE) of the films. Structural characterization using Fourier transformation infrared (FTIR) spectroscopy and X-ray diffraction (XRD) indicated that the presence of GLY altered the intensity of the bands (from 1200 to 800cm(-1)) and crystallinity. The characterization of the thermal properties indicated that an increase in the agar content produces a decrease in the melting temperature and augments the heat of fusion. Similar tendencies were observed in plasticized films, but at different magnification. The formulation that demonstrated the lowest mechanical properties contained 25wt.% agar, whereas the formulation that contained 75wt.% agar demonstrated a significant improvement. The water vapor transmission rate (WVTR) and surface morphology analysis demonstrated that the structure of PVA-agar films is reorganized upon GLY addition. The physicochemical properties of PVA-agar films using GLY as a plasticizer provide information for the application of this formulation as packaging material for specific food applications. PMID:24875313

  12. Ceftibuten-containing agar plate for detecting group B streptococci with reduced penicillin susceptibility (PRGBS).

    PubMed

    Kamiya, Chitose; Kimura, Kouji; Doyama, Yo; Miyazaki, Akira; Morimoto, Makiko; Banno, Hirotsugu; Nagano, Noriyuki; Jin, Wanchun; Wachino, Jun-ichi; Yamada, Keiko; Arakawa, Yoshichika

    2015-08-01

    Penicillins remain first-line agents for treatment of group B Streptococcus (Streptococcus agalactiae; GBS) infections; however, several reports have confirmed the existence of GBS with reduced penicillin susceptibility (PRGBS). Because no selective agar plates for detection of PRGBS are available to date, in this investigation, we developed the selective agar plate for detection of PRGBS. We used 19 genetically well-confirmed PRGBS isolates and 38 penicillin-susceptible GBS isolates identified in Japan. For preparation of trial PRGBS-selective agar plates, we added 1 of antimicrobial agents (among oxacillin, ceftizoxime, and ceftibuten) to a well-established GBS-selective agar plate. Among 12 trial PRGBS-selective agar plates, Muller-Hinton agar containing 128 μg/mL ceftibuten with 5% sheep blood, 8 μg/mL gentamicin, and 12 μg/mL nalidixic acid was the most appropriate selective agar for PRGBS, showing 100% sensitivity and 81.6% specificity. In cases of potential nosocomial spread of PRGBS, the selective agar plate could be useful and reliable. PMID:25959629

  13. Effects of season on the yield and quality of agar from Gracilaria species (Gracilariaceae, Rhodophyta).

    PubMed

    Marinho-Soriano, E; Bourret, E

    2003-12-01

    The effect of season on yield and physical properties of agars extracted from Gracia gracilis and G. bursa-pastoris were determined. The agar yield from G. gracilis was maximum during spring (30%) and minimum during autumn (19%). In G. bursa-pastoris, the agar yield was greatest in summer (36%) and lowest in winter (23%). Agar yield from G. bursa-pastoris was positively correlated with temperature (r=0.94; P<0.01) and salinity (r=0.97; P<0.01) and negatively with nitrogen content (r=-0.93; P<0.01). Agar gel strengths fluctuated from 229 to 828 gcm(-2) and 23 to 168 gcm(-2) for G. gracilis and G. bursa-pastoris, respectively. The gelling temperature showed significant seasonal variation for both species. Chemical analysis of agar from the two seaweeds indicated variation in 3,6-anhydrogalactose and sulfate content (P<0.01). Furthermore, there was an inverse correlation between the two chemical variables. In general, agar extracted from G. gracilis possessed better qualities than agar extracted from G. bursa-pastoris and can be considered a candidate for industrial use. PMID:14575957

  14. Lithium chloride-sodium propionate agar for the enumeration of bifidobacteria in fermented dairy products.

    PubMed

    Lapierre, L; Undeland, P; Cox, L J

    1992-05-01

    Lithium chloride-sodium propionate agar has been developed for the enumeration of bifidobacteria in fermented dairy products. The medium contains lithium chloride and sodium propionate to inhibit the growth of other lactic acid bacteria. Pure cultures of bifidobacteria, lactobacilli, and streptococci were tested for growth in this medium. With one exception, all bifidobacteria were able to grow in this medium and in a nonselective agar with a difference not exceeding .4 log units. However, none of the lactobacilli tested and only one strain each of Streptococcus salivarius ssp. thermophilus and Lactococcus lactis ssp. cremoris grew in lithium chloride-sodium propionate agar. In those cases, the numbers of colonies were lower in lithium chloride-sodium propionate agar by 1.26 and 2.51 log units, respectively, compared with a nonselective agar. Bifidobacteria were also selectively isolated from all fermented milks and cheeses analyzed. PMID:1317893

  15. [Evaluation of a new medium, eggplant (Solanum melongena) agar as a screening medium for Cryptococcus neoformans in environmental samples].

    PubMed

    Sengul, Mustafa; Ergin, Cağrı; Kartal, Tuğba

    2014-04-01

    Cryptococcus neofomans is an encapsulated yeast-like fungus that causes life-threatening infections, especially in immunosuppresive patients. C.neoformans infection is believed to be acquired via inhalation of aerosolized particles from the environment. Avian guano, decaying tree hollows and soil are the related known environmental niches. Brown pigmented yeast growth from the precursors in growth media is an important step for the identification and isolation of C.neoformans. Seeds of plants in nature are preferred owing to easy accessibility and low costs for the preparation of such media. Guizotia abysinicca (Niger seed) as Staib agar, Helianthus annus (Sunflower) as Pal's medium, Brassica nigra (Mustard) agar, tobacco agar, Mucuna pruriens (Velvet bean) seed agar, Perilla frutescens (Beefsteak plant) seed agar, Rubus fruticosus (Blackberry) agar and ground red hot pepper agar are pigment-based selective media for the differentiation of C.neoformans. The aim of this study was to observe the pigment production of C.neoformans in a new medium based on eggplant (Solanum melongena) and also to compare its performance with the simplified Staib, Pal's and tobacco agar for isolation from the environment. Three different eggplant-based medium (S.melongena Melanzaza viserba, S.melongena Pinstripe F1 and S.ovigerum Ivory F1) were included in the study. Pigment-forming eggplant medium, simplified Staib agar, Pal's agar and tobacco agar were used for the cultivation of the environmental swabbed samples from 19 Eucalyptus camaldulensis trunk hollows in continuous colonization region. While pigment formation were observed with S.melongena Melanzaza viserba and S.melongena Pinstripe F1 containing media, S.ovigerum Ivory F1 medium was found to be non-reactive. In colonization area (Gökova-Akyaka, Turkey), 11 (57.9%) out of 19 E.camaldulensis samples were positive with simplified Staib agar, Pal's agar and eggplant agar while 10 (52.6%) of them are positive with tobacco agar. C.neoformans colony forming unit (cfu) per plate were found as 51, 57 and 48 (median values) on simplified Staib agar, Pal's agar and eggplant agar, respectively, while tobacco agar has lower performance with 33 cfu/petri. No statistically significant difference were found between simplified Staib agar, Pal's agar and eggplant agar's performances for C.neoformans isolations from the nature (p=0.71). In conclusion, easily prepared eggplant agar is as functional as widely used media such as simplified Staib agar and Pal's agar for the isolation of C.neoformans from the natural environment. PMID:24819266

  16. Blue ocean strategy.

    PubMed

    Kim, W Chan; Mauborgne, Renée

    2004-10-01

    Despite a long-term decline in the circus industry, Cirque du Soleil profitably increased revenue 22-fold over the last ten years by reinventing the circus. Rather than competing within the confines of the existing industry or trying to steal customers from rivals, Cirque developed uncontested market space that made the competition irrelevant. Cirque created what the authors call a blue ocean, a previously unknown market space. In blue oceans, demand is created rather than fought over. There is ample opportunity for growth that is both profitable and rapid. In red oceans--that is, in all the industries already existing--companies compete by grabbing for a greater share of limited demand. As the market space gets more crowded, prospects for profits and growth decline. Products turn into commodities, and increasing competition turns the water bloody. There are two ways to create blue oceans. One is to launch completely new industries, as eBay did with online auctions. But it's much more common for a blue ocean to be created from within a red ocean when a company expands the boundaries of an existing industry. In studying more than 150 blue ocean creations in over 30 industries, the authors observed that the traditional units of strategic analysis--company and industry--are of limited use in explaining how and why blue oceans are created. The most appropriate unit of analysis is the strategic move, the set of managerial actions and decisions involved in making a major market-creating business offering. Creating blue oceans builds brands. So powerful is blue ocean strategy, in fact, that a blue ocean strategic move can create brand equity that lasts for decades. PMID:15559577

  17. Thermodynamically stable blue phases.

    PubMed

    Castles, F; Morris, S M; Terentjev, E M; Coles, H J

    2010-04-16

    We show theoretically that flexoelectricity stabilizes blue phases in chiral liquid crystals. Induced internal polarization reduces the elastic energy cost of splay and bend deformations surrounding singular lines in the director field. The energy of regions of double twist is unchanged. This in turn reduces the free energy of the blue phase with respect to that of the chiral nematic phase, leading to stability over a wider temperature range. The theory explains the discovery of large temperature range blue phases in highly flexoelectric "bimesogenic" and "bent-core" materials, and predicts how this range may be increased further. PMID:20482018

  18. Code blue: seizures.

    PubMed

    Hoerth, Matthew T; Drazkowski, Joseph F; Noe, Katherine H; Sirven, Joseph I

    2011-06-01

    Eyewitnesses frequently perceive seizures as life threatening. If an event occurs on the hospital premises, a "code blue" can be called which consumes considerable resources. The purpose of this study was to determine the frequency and characteristics of code blue calls for seizures and seizure mimickers. A retrospective review of a code blue log from 2001 through 2008 identified 50 seizure-like events, representing 5.3% of all codes. Twenty-eight (54%) occurred in inpatients; the other 22 (44%) events involved visitors or employees on the hospital premises. Eighty-six percent of the events were epileptic seizures. Seizure mimickers, particularly psychogenic nonepileptic seizures, were more common in the nonhospitalized group. Only five (17.9%) inpatients had a known diagnosis of epilepsy, compared with 17 (77.3%) of the nonhospitalized patients. This retrospective survey provides insights into how code blues are called on hospitalized versus nonhospitalized patients for seizure-like events. PMID:21546315

  19. A Hidden Pitfall in the Preparation of Agar Media Undermines Microorganism Cultivability

    PubMed Central

    Tanaka, Tomohiro; Kawasaki, Kosei; Daimon, Serina; Kitagawa, Wataru; Yamamoto, Kyosuke; Tamaki, Hideyuki; Tanaka, Michiko; Nakatsu, Cindy H.

    2014-01-01

    Microbiologists have been using agar growth medium for over 120 years. It revolutionized microbiology in the 1890s when microbiologists were seeking effective methods to isolate microorganisms, which led to the successful cultivation of microorganisms as single clones. But there has been a disparity between total cell counts and cultivable cell counts on plates, often referred to as the “great plate count anomaly,” that has long been a phenomenon that still remains unsolved. Here, we report that a common practice microbiologists have employed to prepare agar medium has a hidden pitfall: when phosphate was autoclaved together with agar to prepare solid growth media (PT medium), total colony counts were remarkably lower than those grown on agar plates in which phosphate and agar were separately autoclaved and mixed right before solidification (PS medium). We used a pure culture of Gemmatimonas aurantiaca T-27T and three representative sources of environmental samples, soil, sediment, and water, as inocula and compared colony counts between PT and PS agar plates. There were higher numbers of CFU on PS medium than on PT medium using G. aurantiaca or any of the environmental samples. Chemical analysis of PT agar plates suggested that hydrogen peroxide was contributing to growth inhibition. Comparison of 454 pyrosequences of the environmental samples to the isolates revealed that taxa grown on PS medium were more reflective of the original community structure than those grown on PT medium. Moreover, more hitherto-uncultivated microbes grew on PS than on PT medium. PMID:25281372

  20. On the properties of agar gel containing ionic and non-ionic surfactants.

    PubMed

    Prasad, Kamalesh; Siddhanta, A K; Rakshit, A K; Bhattacharya, Amit; Ghosh, Pushpito K

    2005-04-01

    Rheological and thermal properties of agar sol and gel in presence of various cationic, anionic and non-ionic surfactants are reported. The agar used was from the red seaweed Gelidiella acerosa. The gel strength, viscosity, rigidity (G'), gelling temperature and melting temperature were observed to decrease in presence of non-ionic surfactants whereas these were enhanced in presence of ionic surfactants. TGA studies showed that 1.5% agar gels containing non-ionic surfactants lose water at a lower temperature than the control agar gel whereas gels containing ionic surfactants hold on to water more tenaciously. DSC studies, on the other hand, show that the gel to sol transition occurs at lower temperatures in presence of non-ionic surfactants and at higher temperature in presence of ionic surfactants when compared with the control gel. The non-ionic surfactants, Triton X-100 and Brij 35, enabled relatively concentrated agar extractive to be filtered readily, as a result of which water usage in the process could be reduced by 50%. The surfactant was subsequently removed through freeze-thaw operations to restore the gelling capacity of the agar. The finding that 0.3-0.4% (w/v) sodium lauryl sulfate (SLS) lowers the sol-gel transition temperature from 41 to 36 degrees C without adversely affecting gel strength is another useful outcome of the study that may enable better formulations of bacteriological agar to be prepared. PMID:15811467

  1. Detection of Agar, by Analysis of Sugar Markers, Associated with Bacillus Anthracis Spores, After Culture

    SciTech Connect

    Wunschel, David S.; Colburn, Heather A.; Fox, Alvin; Fox, Karen F.; Harley, William M.; Wahl, Jon H.; Wahl, Karen L.

    2008-08-01

    Detection of small quantities of agar associated with spores of Bacillus anthracis could provide key information regarding its source or growth characteristics. Agar, widely used in growth of bacteria on solid surfaces, consists primarily of repeating polysaccharide units of 3,6-anhydro-L-galactose (AGal) and galactose (Gal) with sulfated and O-methylated galactoses present as minor constituents. Two variants of the alditol acetate procedure were evaluated for detection of potential agar markers associated with spores. The first method employed a reductive hydrolysis step, to stabilize labile anhydrogalactose, by converting to anhydrogalactitol. The second eliminated the reductive hydrolysis step simplifying the procedure. Anhydrogalactitol, derived from agar, was detected using both derivatization methods followed by gas chromatography-mass spectrometry (GC-MS) analysis. However, challenges with artefactual background (reductive hydrolysis) or marker destruction (hydrolysis) lead to the search for alternative sugar markers. A minor agar component, 6-O-methyl galactose (6-O-M gal), was readily detected in agar-grown but not broth-grown bacteria. Detection was optimized by the use of gas chromatography-tandem mass spectrometry (GC-MS-MS). With appropriate choice of sugar marker and analytical procedure, detection of sugar markers for agar has considerable potential in microbial forensics.

  2. Factors Affecting Selectivity of Brilliant Green-Phenol Red Agar for Salmonellae

    PubMed Central

    Moats, W. A.; Kinner, J. A.

    1974-01-01

    Commercial brilliant green (BG)-sulfa agar was found to be nonselective toward a test series of Enterobacteriaceae. Various formulations of BG were prepared by using Trypticase soy agar (BBL) as a base. Results were more reproducible when BG dye was added after sterilization than before. Sulfonamides improved selectivity as compared with brilliant green alone. Sulfanilamide (SN) was slightly more selective for salmonellae than other sulfonamides tested. Bile salts and sodium dodecyl sulfate markedly reduced the toxicity of BG to all the test bacteria. Enterobacter strains were most difficult to inhibit. A combination of 5 mg of BG and 1 g of SN/liter prevented growth of Proteus mirabilis and Escherichia coli and retarded growth of Enterobacter strains. The BG-SN agars were superior in selectivity to a series of commercial agars tested, and numbers of salmonellae recovered on BG-SN agar and Trypticase soy agar (BBL) were the same. Brilliant green agars with various degrees of selectivity are described. PMID:4589120

  3. A note on a selective agar medium for the enumeration of Flavobacterium species in water.

    PubMed

    Flint, K P

    1985-12-01

    A selective nutrient agar medium containing kanamycin at 50 micrograms/ml was developed for the isolation and enumeration of yellow-pigmented colonies from the River Sowe, Coventry. Such organisms were shown to be members of the heterogeneous genus Flavobacterium. Typically, yellow pigmented colonies constituted less than 10% of the colonies on nutrient agar alone but up to 70% on nutrient agar plus kanamycin. This medium is a useful addition to the range of media available for the isolation and further ecological study of particular species of this important group of micro-organisms. PMID:3831005

  4. Agar impression materials, dimensional stability and surface detail sharpness following treatment with disinfectant solutions.

    PubMed

    Olsson, S; Bergman, B; Bergman, M

    1987-01-01

    The influence of seven dissimilar disinfectants on the dimensional stability and the surface detail sharpness of two agar impression materials was studied. Two methods for treatment with disinfectant solutions were tested--immersion for 1 hour and spraying. In contrast to immersion the spraying method had no obvious influence on the agar material. It is concluded that if the disinfection method necessitates immersion of the impression in a solution for 1 hour or more the use of agar impression materials should be avoided. PMID:3480616

  5. Modeling of the Bacillus subtilis Bacterial Biofilm Growing on an Agar Substrate

    PubMed Central

    Wang, Xiaoling; Wang, Guoqing; Hao, Mudong

    2015-01-01

    Bacterial biofilms are organized communities composed of millions of microorganisms that accumulate on almost any kinds of surfaces. In this paper, a biofilm growth model on an agar substrate is developed based on mass conservation principles, Fick's first law, and Monod's kinetic reaction, by considering nutrient diffusion between biofilm and agar substrate. Our results show biofilm growth evolution characteristics such as biofilm thickness, active biomass, and nutrient concentration in the agar substrate. We quantitatively obtain biofilm growth dependence on different parameters. We provide an alternative mathematical method to describe other kinds of biofilm growth such as multiple bacterial species biofilm and also biofilm growth on various complex substrates. PMID:26355542

  6. Agar and broth dilution methods to determine the minimal inhibitory concentration (MIC) of antimicrobial substances.

    PubMed

    Wiegand, Irith; Hilpert, Kai; Hancock, Robert E W

    2008-01-01

    The aim of broth and agar dilution methods is to determine the lowest concentration of the assayed antimicrobial agent (minimal inhibitory concentration, MIC) that, under defined test conditions, inhibits the visible growth of the bacterium being investigated. MIC values are used to determine susceptibilities of bacteria to drugs and also to evaluate the activity of new antimicrobial agents. Agar dilution involves the incorporation of different concentrations of the antimicrobial substance into a nutrient agar medium followed by the application of a standardized number of cells to the surface of the agar plate. For broth dilution, often determined in 96-well microtiter plate format, bacteria are inoculated into a liquid growth medium in the presence of different concentrations of an antimicrobial agent. Growth is assessed after incubation for a defined period of time (16-20 h) and the MIC value is read. This protocol applies only to aerobic bacteria and can be completed in 3 d. PMID:18274517

  7. Proton beam writing of microstructures in Agar gel for patterned cell growth

    NASA Astrophysics Data System (ADS)

    Larisch, Wolfgang; Koal, Torsten; Werner, Ronald; Hohlweg, Marcus; Reinert, Tilo; Butz, Tilman

    2011-10-01

    A rather useful prerequisite for many biological and biophysical studies, e.g., for cell-cell communication or neuronal networks, is confined cell growth on micro-structured surfaces. Solidified Agar layers have smooth surfaces which are electrically neutral and thus inhibit receptor binding and cell adhesion. For the first time, Agar microstructures have been manufactured using proton beam writing (PBW). In the irradiated Agar material the polysaccharides are split into oligosaccharides which can easily be washed off leaving Agar-free areas for cell adhesion. The beam diameter of 1 μm allows the fabrication of compartments accommodating single cells which are connected by micrometer-sized channels. Using the external beam the production process is very fast. Up to 50 Petri dishes can be produced per day which makes this technique very suitable for biological investigations which require large throughputs.

  8. A fresh liver agar substrate for rearing small numbers of forensically important blow flies (Diptera: Calliphoridae)

    USGS Publications Warehouse

    Gruner, Susan V.; Slone, Daniel H.

    2014-01-01

    Forensically important calliphorids can be reared on a mixture of beef liver and agar. Small pieces of meat, especially fresh or frozen beef liver, will desiccate in 2–6 h, but this simple-to-make feeding substrate remains moist for at least 12 h at 25 and 30°C without desiccation, even in small (5 g) amounts. We determined the survivorship of small numbers of Chrysomya megacephala (F.) (first-instar larvae to adult eclosion) raised on 5 g of liver agar and fresh beef liver. We found that all larvae raised on 5 g of liver died due to desiccation, but survivorship on 5 g of liver agar was equivalent to that on larger (50 g) pieces of either liver agar or beef liver.

  9. [THE APPLICATION OF SELECTIVE CHROMOGENIC AGAR FOR DETECTING ENTEROBACTERIA WITH PRODUCTION OF BETA-LACTAMASES].

    PubMed

    Korobova, A G; Frolova, L N; Kliasova, G A

    2015-11-01

    The detection of enterobacteria with production of beta-lactamases of extended spectrum in selective chromogenic agar was analyzed The results ofdetection of beta-lactamases of extended spectrum was compared with "double disc" technique. The smears from mucous membrane of guttur and rectum from patients were analyzed in parallel on solid growth agar (Endo or Mac Conkey) and on selective agar CHROMagartm ESBL (CHROMagar France). The production of beta-lactamases of extended spectrum was confirmed using "double discs" technique. To exclude hyper-production of ampC beta-lactamases E-test was applied containing cefotetan and cefotetan with cloxacillin. The sampling consisted of 1552 samples from patients. The study permitted to isolate 1243 strains of enterobacteria on agar Endo or Mac Conkey and 409 strains of enterobacteria on selective agar CHROMagartm ESBL (Escherichia coli n = 226, Klebsiella pneumoniae n = 105, enterobacter spp. n = 35, Citrobacter spp. n = 21, others n = 22). The application of "double discs" technique confirmed production of beta-lactamases of extended spectrum in 386 (94%) out of 409 strains isolated on agar CHROMagartm ESBL. In 23 (6%) of strains no confirmation was established and hyper-production of ampC of beta-lactamases was established 15 out of total. Additionally, 8 were sensitive to cephalosporin of third generation. All enterobacteria isolated on agar Endo or Mac Conkey also were tested by "double discs" technique. Overall, 394 strains of enterobacteria with production of beta-lactamases of extended spectrum were obtained. On all agars (agar Endo or Mac Conkey and CHROMagartm ESBL)--263 (67%) strains; only on CHROMagartm ESBL--123 (31%) and only on agar Endo or Mac Conkey--8 (2%) (p < 0.0001). The sensitivity of selective agar CHROMagartm ESBL made up to 98% and specificity--97%. The resolution about detection of enterobacteria producing beta-lactamases of extended spectrum were submitted to clinic in 18-24 hours after arrival ofsamplesfrom patients in laboratory. The CHR OMagartm ESBL has higher sensitivity and specificity to detect enterobacteria with production of beta-lactamases of extended spectrum and can be applied in common laboratory practice. PMID:26999867

  10. Agars of Gelidiella acerosa of west and southeast coasts of India.

    PubMed

    Prasad, Kamalesh; Siddhanta, A K; Ganesan, M; Ramavat, B K; Jha, B; Ghosh, Pushpito K

    2007-07-01

    Seventeen agar samples were extracted from Gelidiella acerosa (Forsskal) Feldmann and Hamel (Rhodophyta, Gelidiales) specimens collected from nine different sites on the Indian coast-five from southeast coast and four from the west coast. The agar samples were analysed. The stability characteristics of the gels of selected agar samples were studied by rheometry under applied stress conditions, i.e. variation of the storage (G') and loss moduli (G'') were studied under varying frequency and duration (time) of the stress applied. Yield, apparent and dynamic viscosities, gelling and melting temperatures, 3,6-anhydrogalactose (3,6-AG), sulphate contents and TGA (Thermogravimetric Analysis) measurements of the products were done. It was observed that the best quality agar was produced by G. acerosa occurring in the Gulf of Mannar region in the southeast coast. The gel strengths and the viscosities of agars extracted from Gelidiella acerosa occurring in the Gulf of Mannar ranged from 500 to 700gcm(-2) and 33 to 45cP for 2001 collections and for 2002 collections the corresponding values were 450 to 845gcm(-2) and 55 to 67cP respectively. On the other hand, for the agar samples extracted from the west coast of India, the gel strength and viscosities values ranged from 225 to 400gcm(-2) and from 15 to 30cP, respectively. The agars obtained from G. acerosa collected from southeast coast have been found to be suitable for bacterial culture and molecular biology. This is the first report of superior quality of agar from the Indian agarophytes. PMID:16949817

  11. Low density, microcellular, dopable, agar/gelatin foams for pulsed power experiments

    SciTech Connect

    McNamara, W.F.; Aubert, J.H.

    1997-04-01

    Low-density, microcellular foams prepared from the natural polymers agar and gelatin have been developed for pulsed-power physics experiments. Numerous experiments were supported with foams having densities at or below 10 mg/cm{sup 3}. For some of the experiments, the agar/gelatin foam was uniformly doped with metallic elements using soluble salts. Depending on the method of preparation, cell sizes were typically below 10 microns and for one process were below 1.0 micron.

  12. Genome sequence of the agar-degrading marine bacterium Alteromonadaceae sp. strain G7.

    PubMed

    Kwak, Min-Jung; Song, Ju Yeon; Kim, Byung Kwon; Chi, Won-Jae; Kwon, Soon-Kyeong; Choi, Soobeom; Chang, Yong-Keun; Hong, Soon-Kwang; Kim, Jihyun F

    2012-12-01

    Here, we present the high-quality draft genome sequence of the agar-degrading marine gammaproteobacterium Alteromonadaceae sp. strain G7, which was isolated from coastal seawater to be utilized as a bioresource for production of agar-derived biofuels. The 3.91-Mb genome contains a number of genes encoding algal polysaccharide-degrading enzymes such as agarases and sulfatases. PMID:23209220

  13. Evidence of agar gel electrophoresis changes of lipoprotein-X after phospholipase A and deoxycholic acid.

    PubMed

    Frisón, J C; Ras, M R; Rubiés-Prat, J; Masdeu, S; Schwartz, S

    1977-01-01

    The effect of phospholipase A from snake venom and deoxycholic acid on lipoprotein-X (LP-X) recovered from the cathode side of a previous agar gel electrophoresis is described. Adding phospholipase A and deoxycholic acid to the removed cathodal fraction is followed by a marked migration to the anode side on a second electrophoresis procedure. This seems to confirm that phospholipase A and bile salts on LP-X particles modifying their agar gel electrophoretic migration characteristics. PMID:210069

  14. [GROWTH OF MICROMYCETES FROM DIFFERENT ECOLOGICAL NICHES ON AGAR NUTRIENT MEDIA].

    PubMed

    Kurchenko, I M; Yurieva, E M; Voychuk, S I

    2015-01-01

    Radial growth rate of (K(r)) 153 strains 6 species of micromycetes from different ecological niches was studied on 7 agar media: three standard (malt extract agar, potato-dextrose agar, Czapek's agar), and on agar media with plant polymers (carboxymethylcellulose, xylan, soluble starch and apple pectin). Endophytic and plant pathogenic strains (biotrophs) of all studied species did not differ significantly in their ability to grow on nutrient media of different composition--average values of K(r) for these two groups were the same (0,200 and 0,199 mm/h, respectively). Soil micromycetes (saprophytes) characterized by the lowest average growth rate (0,169 mm/h) and significantly differed from the endophytic and plant pathogenic ones. Average of the radial growth rates of studied microscopic fungi were higher on standard nutrient media than with plant polymers ones. Growth parameters of endophytes and plant pathogens of all studied species on various agar media differed from the soil strains. High growth rate of endophytic and plant pathogenic strains of Fusarium poae, Alternaria alternata and Ceratocystis sp. provides them the rapid colonization of plants. Penicillium funiculosum strains equally can exist as saprophytes in soil and as endophytic plant symbionts. A wide range of K(r) variation of endophytic dark pigmented Mycelia sterilia indicates the presence in this group of different species of micromycetes, which have no sporulation. PMID:26638483

  15. Complex impedance and conductivity of agar-based ion-conducting polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Nwanya, A. C.; Amaechi, C. I.; Udounwa, A. E.; Osuji, R. U.; Maaza, M.; Ezema, F. I.

    2015-04-01

    Agar-based electrolyte standing films with different salts and weak acids as ion and proton conductors were prepared and characterized by X-ray diffraction, UV-visible spectrophotometry, photoluminescence emission spectroscopy and electrochemical impedance spectroscopy. The salts used are lithium perchlorate (LiClO4) and potassium perchlorate (KClO4), while the weak acids used are acetic acid (CH3COOH) and lactic acid (C3H6O3). The values of the ion conductivity obtained for the agar-based polymer films are 6.54 × 10-8, 9.12 × 10-8, 3.53 × 10-8, 2.24 × 10-8 S/cm for the agar/acetic acid, agar/lactic acid, agar/LiClO4 and agar/KClO4 polymer films, respectively. As a function of temperature, the ion conductivity exhibits an Arrhenius behavior and the estimated activation energy is ≈0.1 eV for all the samples. The samples depicted high values of dielectric permittivity toward low frequencies which is due mostly to electrode polarization effect. The samples showed very high transparency (85-98 %) in the visible region, and this high transparency is one of the major requirements for application in electrochromic devices (ECD). The values of conductivity and activation energy obtained indicate that the electrolytes are good materials for application in ECD.

  16. Modification of kanamycin-esculin-azide agar to improve selectivity in the enumeration of fecal streptococci from water samples.

    PubMed Central

    Audicana, A; Perales, I; Borrego, J J

    1995-01-01

    Kanamycin-esculin-azide agar was modified by increasing the concentration of sodium azide to 0.4 g liter-1 and replacing kanamycin sulfate with 5 mg of oxolinic acid liter-1. The modification, named oxolinic acid-esculin-azide (OAA) agar, was compared with Slanetz-Bartley and KF agars by using drinking water and seawater samples. The OAA agar showed higher specificity, selectivity, and recovery efficiencies than those obtained by using the other media. In addition, no confirmation of typical colonies was needed when OAA agar was used, which significantly shortens the time of sample processing and increases the accuracy of the method. PMID:8534085

  17. Blue honeysuckle list 47

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript summarizes descriptions for two newly released Lonicera caerulea L., blue honeysuckle, cultivars released for northern production. This fruit is popular in Russia and in Japan, particularly Hokkaido. It has possibility as a new fruit cultivar for North America. The University of Sask...

  18. Great Blue Heron

    Great Blue Herons are found throughout much of North America, but are always associated with water. Because they fish by sight, they need relatively shallow water. Release of too much water through the canals north of the Everglades can interfere with their ability to find food....

  19. Comparative dermatology: blue nevus.

    PubMed

    Barros, Jefferson Alfredo de; Kafler, Cristiane Calcidoni; Barros, Juliano Cesar de; Proto, Rodrigo Sestito; Priscila dos Santos, Costa; Machado Filho, Carlos D'Apparecida

    2012-01-01

    There are elements in nature that may be compared to some dermatological lesions, such as the black pearl, which is very similar to a cellular blue nevus observed in the gluteus region of a 31-year-old male patient. PMID:22892793

  20. Evaluation of CP Chromo Select Agar for the enumeration of Clostridium perfringens from water.

    PubMed

    Manafi, Mammad; Waldherr, Kerstin; Kundi, Michael

    2013-10-01

    The European Directive on drinking water quality has included mCP agar as the reference method for recovering Clostridium perfringens from drinking waters. In the present study, three media (mCP, TSCF and CP Chromo Select Agar) were evaluated for recovery of C. perfringens in different surface water samples. Out of 139 water samples, using a membrane filtration technique, 131 samples (94.2%) were found to be presumptively positive for C. perfringens in at least one of the culture media. Green colored colonies on CP Chromo Select Agar (CCP agar) were counted as presumptive C. perfringens isolates. Out of 483 green colonies on CCP agar, 96.3% (465 strains, indole negative) were identified as C. perfringens, and 15 strains (3.1%) were indole positive and were identified as Clostridium sordellii, Clostridium bifermentans or Clostridium tetani. Only 3 strains (0.6%) gave false positive results and were identified as Clostridium fallax, Clostridium botulinum, and Clostridium tertium. Variance analysis of the data obtained shows statistically no significant differences in the counts obtained between media employed in this work. The mCP method is very onerous for routine screening and bacterial colonies could not be used for further biochemical testing. The colonies on CCP and TSCF were easy to count and subculture for confirmation tests. TSCF detects sulfite-reducing clostridia, including species other than C. perfringens, and in some cases excessive blackening of the agar frustrated counting of the colonies. If the contamination was too high, TSCF did not consistently produce black colonies and as a consequence, the colonies were white and gave false negative results. On the other hand, the identification of typical and atypical colonies isolated from all media demonstrated that CCP agar was the most useful medium for C. perfringens recovery in water samples. PMID:23816139

  1. Migration of chemotactic bacteria in soft agar: role of gel concentration.

    PubMed

    Croze, Ottavio A; Ferguson, Gail P; Cates, Michael E; Poon, Wilson C K

    2011-08-01

    We study the migration of chemotactic wild-type Escherichia coli populations in semisolid (soft) agar in the concentration range C = 0.15-0.5% (w/v). For C≲0.35%, expanding bacterial colonies display characteristic chemotactic rings. At C = 0.35%, however, bacteria migrate as broad circular bands rather than sharp rings. These are growth/diffusion waves arising because of suppression of chemotaxis by the agar and have not been previously reported experimentally to our knowledge. For C = 0.4-0.5%, expanding colonies do not span the depth of the agar and develop pronounced front instabilities. The migration front speed is weakly dependent on agar concentration at C < 0.25%, but decreases sharply above this value. We discuss these observations in terms of an extended Keller-Segel model for which we derived novel transport parameter expressions accounting for perturbations of the chemotactic response by collisions with the agar. The model makes it possible to fit the observed front speed decay in the range C = 0.15-0.35%, and its solutions qualitatively reproduce the observed transition from chemotactic to growth/diffusion bands. We discuss the implications of our results for the study of bacteria in porous media and for the design of improved bacteriological chemotaxis assays. PMID:21806920

  2. Antimicrobial and physical-mechanical properties of agar-based films incorporated with grapefruit seed extract.

    PubMed

    Kanmani, Paulraj; Rhim, Jong-Whan

    2014-02-15

    The use of synthetic petroleum based packaging films caused serious environmental problems due to their difficulty in recycling and poor biodegradability. Therefore, present study was aimed to develop natural biopolymer-based antimicrobial packaging films as an alternative for the synthetic packaging films. As a natural antimicrobial agent, grapefruit seed extract (GSE) has been incorporated into agar to prepare antimicrobial packaging film. The films with different concentrations of GSE were prepared by a solvent casting method and the resulting composite films were examined physically and mechanically. In addition, the films were characterized by FE-SEM, XRD, FT-IR and TGA. The incorporation of GSE caused increase in color, UV barrier, moisture content, water solubility and water vapor permeability, while decrease in surface hydrophobicity, tensile strength and elastic modulus of the films. As the concentration of GSE increased from 0.6 to 13.3 μg/mL, the physical and mechanical properties of the films were affected significantly. The addition of GSE changed film microstructure of the film, but did not influence the crystallinity of agar and thermal stability of the agar-based films. The agar/GSE films exhibited distinctive antimicrobial activity against three test food pathogens, such as Listeria monocytogenes, Bacillus cereus and Escherichia coli. These results suggest that agar/GSE films have potential to be used in an active food packaging systems for maintaining food safety and extending the shelf-life of the packaged food. PMID:24507339

  3. Characterization of bionanocomposite films prepared with agar and paper-mulberry pulp nanocellulose.

    PubMed

    Reddy, Jeevan Prasad; Rhim, Jong-Whan

    2014-09-22

    Crystallized nanocellulose (CNC) was separated from paper-mulberry (Broussonetia kazinoki Siebold) bast pulp by sulfuric acid hydrolysis method and they were blended with agar to prepare bionanocomposite films. The effect of CNC content (1, 3, 5 and 10 wt% based on agar) on the mechanical, water vapor permeability (WVP), and thermal properties of the nanocomposites were studied. Changes of the cellulose fibers in structure, morphology, crystallinity, and thermal properties of the films were evaluated using FT-IR, TEM, SEM, XRD, and TGA analysis methods. The CNC was composed of fibrous and spherical or elliptic granules of nano-cellulose with sizes of 50-60 nm. Properties of agar film such as mechanical and water vapor barrier properties were improved significantly (p<0.05) by blending with the CNC. The tensile modulus and tensile strength of agar film increased by 40% and 25%, respectively, in the composite film with 5 wt% of CNC, and the WVP of agar film decreased by 25% after formation of nanocomposite with 3 wt% of CNC. The CNC obtained from the paper-mulberry bast pulp can be used as a reinforcing agent for the preparation of bio-nanocomposites, and they have a high potential for the development of completely biodegradable food packaging materials. PMID:24906782

  4. Effects of shape and size of agar gels on heating uniformity during pulsed microwave treatment.

    PubMed

    Soto-Reyes, Nohemí; Temis-Pérez, Ana L; López-Malo, Aurelio; Rojas-Laguna, Roberto; Sosa-Morales, María Elena

    2015-05-01

    Model gel systems with different shape (sphere, cylinder, and slab) and size (180 and 290 g) were prepared with agar (5%) and sucrose (5%). Dielectric constant (ε'), loss factor (ε"), thermophysical properties, and temperature distribution of the model system were measured. Each agar model system was immersed and suspended in water, and then, heated in a microwave oven with intermittent heating until the core temperature reached 50 °C. The ε' and ε" of agar gels decreased when frequency increased. The density and thermal conductivity values of the agar gels were 1033 kg/m(3) and 0.55 W/m °C, respectively. The temperature distribution of sphere, cylinder, and slab was different when similar power doses were applied. The slab reached 50 °C in less time (10 min) and showed a more uniform heating than spheres and cylinders in both sizes. Agar model systems of 180 g heated faster than those of 290 g. The coldest point was the center of the model systems in all studied cases. Shape and size are critical food factors that affect the heating uniformity during microwave heating processes. PMID:25827444

  5. Migration of Chemotactic Bacteria in Soft Agar: Role of Gel Concentration

    PubMed Central

    Croze, Ottavio A.; Ferguson, Gail P.; Cates, Michael E.; Poon, Wilson C.K.

    2011-01-01

    We study the migration of chemotactic wild-type Escherichia coli populations in semisolid (soft) agar in the concentration range C = 0.15–0.5% (w/v). For C≲0.35%, expanding bacterial colonies display characteristic chemotactic rings. At C = 0.35%, however, bacteria migrate as broad circular bands rather than sharp rings. These are growth/diffusion waves arising because of suppression of chemotaxis by the agar and have not been previously reported experimentally to our knowledge. For C = 0.4–0.5%, expanding colonies do not span the depth of the agar and develop pronounced front instabilities. The migration front speed is weakly dependent on agar concentration at C < 0.25%, but decreases sharply above this value. We discuss these observations in terms of an extended Keller-Segel model for which we derived novel transport parameter expressions accounting for perturbations of the chemotactic response by collisions with the agar. The model makes it possible to fit the observed front speed decay in the range C = 0.15–0.35%, and its solutions qualitatively reproduce the observed transition from chemotactic to growth/diffusion bands. We discuss the implications of our results for the study of bacteria in porous media and for the design of improved bacteriological chemotaxis assays. PMID:21806920

  6. Coiling is Not Essential to Anhydrobiosis by Aphelenchus avenae on Agar Amended with Sucrose

    PubMed Central

    Otsubo, R; Yoshiga, T; Kondo, E; Ishibashi, N

    2006-01-01

    The roles of preconditioning and coiling upon entrance into anhydrobiosis by Aphelenchus avenae were tested via video-assisted analysis at 252°C. Fourth-stage juveniles or young adults of A. avenae were individually placed on 5% agar containing 0.8 M sucrose. Nematodes became quiescent within 3 hr, then gradually resumed a low level of activity and assumed a coiled posture. High desiccation survival rate was recorded when nematodes were incubated on agar for more than 6 hr; the survival rates were 0%, 3%, 73%, and 92% for 0, 2, 6, and 12 hr on agar, respectively. All nematodes placed on agar for 24 hr or more revived after rehydration following desiccation. Once nematodes were on agar for a sufficient time, no difference in desiccation survival was observed between nematodes taking a coiled posture and those uncoiled artificially. Based on these results, exposure to osmotic stress for 6 hr can prepare A. aveae physiologically for anhydrobiosis, but coiling does not appear to be a physiological requirement for desiccation in survival. PMID:19259428

  7. The Blue Emu

    NASA Technical Reports Server (NTRS)

    Descalzi, Doug; Gillett, John; Gordon, Carlton; Keener, ED; Novak, Ken; Puente, Laura

    1993-01-01

    The primary goal in designing the Blue Emu was to provide an airline with a cost efficient and profitable means of transporting passengers between the major cities in Aeroworld. The design attacks the market where a demand for inexpensive transportation exists and for this reason the Blue Emu is an attractive investment for any airline. In order to provide a profitable aircraft, special attention was paid to cost and economics. For example, in manufacturing, simplicity was stressed in structural design to reduce construction time and cost. Aerodynamic design employed a tapered wing which reduced the induced drag coefficient while also reducing the weight of the wing. Even the propulsion system was selected with cost effectiveness in mind, yet also to maintain the marketability of the aircraft. Thus, in every aspect of the design, consideration was given to economics and marketability of the final product.

  8. Voyager 1 'Blue Movie'

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This is the original Voyager 'Blue Movie' (so named because it was built from Blue filter images). It records the approach of Voyager 1 during a period of over 60 Jupiter days. Notice the difference in speed and direction of the various zones of the atmosphere. The interaction of the atmospheric clouds and storms shows how dynamic the Jovian atmosphere is.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 66 images taken once every Jupiter rotation period (about 10 hours). This time-lapse movie uses images taken every time Jupiter longitude 68W passed under the spacecraft. These images were acquired in the Blue filter from Jan. 6 to Feb. 3 1979. The spacecraft flew from 58 million kilometers to 31 million kilometers from Jupiter during that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  9. [DNA and chemical analyses of commercial fly agaric-related products].

    PubMed

    Maruyama, Takuro; Kawahara, Nobuo; Fukiharu, Toshimitsu; Yokoyama, Kazumasa; Makino, Yukiko; Goda, Yukihiro

    2005-04-01

    Since June 6, 2002, psilocin and psilocybin-containing fungi (commonly called "magic mushrooms") have been regulated by the Narcotics and Psychotropics Control Law in Japan. However, various fly agaric-related products are now entering the Japanese market via the internet. In this study, fly agaric-related products available in this way were investigated for raw materials by DNA analysis and for additives by chemical analysis. Nucleotide sequence analysis of the mitochondrial 12S rDNA region suggested that these fly agaric-related products originate from A. muscaria or A. muscaria var. persicina. Furthermore, they were classified into three strains based on the ITS2-LSU nucleotide sequence. Harmine derivatives and/or tryptamine derivatives were detected in some of these products by LC/MS analysis. In accordance with this, the matK gene of Peganum harmala was found in all of the harmine derivative-containing samples. PMID:16018591

  10. Eradication of bovine leukemia virus infection in commercial dairy herds using the agar gel immunodiffusion test.

    PubMed Central

    Shettigara, P T; Samagh, B S; Lobinowich, E M

    1986-01-01

    Demands for bovine leukemia virus test negative breeding cattle and for semen from bovine leukemia virus test negative bulls by several countries have encouraged the eradication of bovine leukemia virus infection from selected herds in Canada. This project was undertaken to evaluate the suitability of the agar gel immunodiffusion test, standardized to detect anti-bovine leukemia virus glycoprotein antibodies, for eradication of bovine leukemia virus from commercial dairy herds. Of nine participating herds, the prevalence rate of bovine leukemia virus infection was low (less than 10%) in three, medium (11-30%) in four and high (greater than 30%) in two. The herds were tested by the agar gel immunodiffusion test, reactors were removed and the herds were then retested at regular intervals. The results indicate that it is possible to eliminate bovine leukemia virus infection from the herds after two to three cycles of agar gel immunodiffusion tests and prompt removal of the reactors. PMID:3019498

  11. Effects of disinfection of combined agar/alginate impressions on the dimensional accuracy of stone casts.

    PubMed

    Hiraguchi, Hisako; Nakagawa, Hisami; Kaketani, Masahiro; Hirose, Hideharu; Nishiyama, Minoru

    2007-05-01

    This study investigated the effects of disinfection of combined agar/alginate impressions on the dimensional accuracy of resultant stone casts. Impressions of a master cast designed to simulate an abutment tooth were prepared by combining each of two brands of cartridge-form agar impression materials with an alginate impression material. The impressions were immersed in 1% sodium hypochlorite for 10 minutes or 2% glutaraldehyde for 30 minutes. The remaining impressions were sprayed with these two disinfectants and then stored in sealed bags for 10, 30, 60, and 120 minutes. Stone casts obtained from the non-disinfected impressions were also prepared as control. Changes in diameter of the stone casts were then measured. Results indicated that storage for 10 minutes after spraying with 1% sodium hypochlorite was an appropriate disinfection method for combined agar/alginate impressions, as well as immersion in 1% sodium hypochlorite for 10 minutes. PMID:17694758

  12. Homogeneous matrix deposition on dried agar for MALDI imaging mass spectrometry of microbial cultures.

    PubMed

    Hoffmann, Thomas; Dorrestein, Pieter C

    2015-11-01

    Matrix deposition on agar-based microbial colonies for MALDI imaging mass spectrometry is often complicated by the complex media on which microbes are grown. This Application Note demonstrates how consecutive short spray pulses of a matrix solution can form an evenly closed matrix layer on dried agar. Compared with sieving dry matrix onto wet agar, this method supports analyte cocrystallization, which results in significantly more signals, higher signal-to-noise ratios, and improved ionization efficiency. The even matrix layer improves spot-to-spot precision of measured m/z values when using TOF mass spectrometers. With this technique, we established reproducible imaging mass spectrometry of myxobacterial cultures on nutrient-rich cultivation media, which was not possible with the sieving technique. Graphical Abstract ᅟ. PMID:26297185

  13. Growth kinetics of Salmonella enterica in Hajna tetrathionate broth, Rappaport broth and modified semisolid Rappaport agar

    PubMed Central

    FUJIHARA, Masatoshi; TABUCHI, Hiroyuki; UEGAKI, Kaho

    2015-01-01

    To determine the appropriate method for isolating Salmonella enterica, we compared the growth of S. enterica serovars using three selective enrichment media. S. enterica was more successfully isolated from artificially contaminated fecal samples after enrichment in Hajna tetrathionate broth or modified semisolid Rappaport agar than in Rappaport broth. Since most bacteria (other than motile S. enterica) do not migrate on modified semisolid Rappaport agar, the growth characteristics of S. enterica can be interpreted easily and quickly. Two S. enterica isolates did not migrate on modified semisolid Rappaport agar, but did grow in Hajna tetrathionate broth, which suggests that the combined use of these selective enrichment media is appropriate for isolating S. enterica. PMID:26498402

  14. An agar diffusion study comparing the antimicrobial activity of Nanoseal with some other endodontic sealers.

    PubMed

    Aal-Saraj, Ali Burak; Ariffin, Zaihan; Masudi, Sam'an Malik

    2012-08-01

    The aim of this study was to evaluate the antimicrobial activity of a new experimental nano-hydroxyapatite epoxy resin-based sealer (Nanoseal) with several other commercially available sealers; AH26, Tubliseal, Sealapex and Roekoseal against Enterococcus faecalis, Pseudomonas aeruginosa, Streptococcus mutans, Streptococcus sobrinus and Escherichia coli for up to 7 days. Agar diffusion was used in this study. Fifty Muller-Hinton agar plates were prepared and divided into five experimental groups (n = 10), for each micro-organism. Another 10 agar plates were used as positive and negative controls. Endodontic sealers were tested against each micro-organism. Inhibition zones produced were recorded. The results of this study showed that all test materials exhibited inhibition zones towards the tested micro-organisms for 7 days except for Roekoseal, which showed no inhibition zones. Nanoseal and AH26 exhibited similar zones of inhibition. Significant difference was found between Nanoseal and the other tested sealers (P < 0.001). PMID:22827817

  15. Blood agar to detect virulence factors in tap water heterotrophic bacteria.

    PubMed Central

    Payment, P; Coffin, E; Paquette, G

    1994-01-01

    Cytolytic colonies were found in 57% of tap water samples, and up to 6% of samples were found to contain bacteria having three or more virulence factors. The factors evaluated were cytotoxicity, hemolysis, cell adherence, and cell invasiveness. Overall, 17% of the samples contained cytolytic colonies that were adherent and hemolytic. Among the media tested, tryptic soy agar with sheep blood (incubated at 35 degrees C for 48 h) was the best medium for the detection of cytolytic colonies. Of the colonies growing on this medium, 13% were cytolytic, whereas on medium R2A, less than 3% were cytolytic. Furthermore, when tryptic soy agar with blood was used, 24% of the samples contained colonies with at least three virulence factors whereas only 5% were positive with R2A. Routine monitoring by using tryptic soy agar with sheep blood is suggested as an appropriate procedure for the detection of bacteria with pathogenic potential in drinking water. PMID:8017913

  16. Homogeneous Matrix Deposition on Dried Agar for MALDI Imaging Mass Spectrometry of Microbial Cultures

    NASA Astrophysics Data System (ADS)

    Hoffmann, Thomas; Dorrestein, Pieter C.

    2015-11-01

    Matrix deposition on agar-based microbial colonies for MALDI imaging mass spectrometry is often complicated by the complex media on which microbes are grown. This Application Note demonstrates how consecutive short spray pulses of a matrix solution can form an evenly closed matrix layer on dried agar. Compared with sieving dry matrix onto wet agar, this method supports analyte cocrystallization, which results in significantly more signals, higher signal-to-noise ratios, and improved ionization efficiency. The even matrix layer improves spot-to-spot precision of measured m/z values when using TOF mass spectrometers. With this technique, we established reproducible imaging mass spectrometry of myxobacterial cultures on nutrient-rich cultivation media, which was not possible with the sieving technique.

  17. Use of Rambach Propylene Glycol Containing Agar for identification of Salmonella spp.

    PubMed Central

    Gruenewald, R; Henderson, R W; Yappow, S

    1991-01-01

    When grown on Rambach Propylene Glycol Containing Agar (Rambach agar), 216 of 230 (93.9%) Salmonella organisms isolated from patients and 54 of 62 (87.1%) Salmonella stock cultures produced a crimson-colored growth. Of the 14 clinical Salmonella isolates which displayed colors other than crimson, 8 were Salmonella typhi, 2 were Salmonella paratyphi A, and 4 belonged to other commonly isolated serotypes. All eight Salmonella stock cultures which failed to produce a crimson color belonged to rarely isolated serotypes. In contrast, of 83 non-Salmonella stock cultures distributed among 29 bacterial species, none produced a crimson color. These results suggest that while Rambach agar cannot preidentify S. typhi and S. paratyphi A, the medium can be used for the presumptive identification and can assist in the definitive identification of the overwhelming majority of Salmonella isolates. PMID:1939598

  18. Serogroup identification of Neisseria meningitidis: comparison of an antiserum agar method with bacterial slide agglutination.

    PubMed Central

    Craven, D E; Frasch, C E; Robbins, J B; Feldman, H A

    1978-01-01

    A serum agar method for serogrouping Neisseria meningitidis is described and compared with conventional bacterial slide agglutination. There was 93% agreement for 300 strains examined individually by each method. Among strains from serogroups A, B, C, Y, and W135, there was 100% correlation, whereas strains from serogroup 29E (Z') had only 67% correlation. The serum agar method was rapid, as well as easy to perform and interpret. The potential benefits of this method for epidemiological studies and reference laboratories processing large numbers of meningococcal isolates are emphasized. Images PMID:96123

  19. Multilaboratory evaluation of an agar diffusion disk susceptibility test for rapidly growing anaerobic bacteria.

    PubMed

    Barry, A L; Fuchs, P C; Gerlach, E H; Allen, S D; Acar, J F; Aldridge, K E; Bourgault, A M; Grimm, H; Hall, G S; Heizmann, W

    1990-01-01

    A multilaboratory collaborative study was undertaken to determine whether the anaerobic disk diffusion test of Horn et al. could be performed reproducibly and accurately. Tests with nine different antimicrobial disks were evaluated. Reproducibility of the agar diffusion disk method was similar to that of the reference agar dilution test procedure. The anaerobic disk diffusion procedure was found to be a potentially useful method for testing some antimicrobial agents against rapidly growing anaerobes belonging to the Bacteroides fragilis group. These promising results warrant further investigations and validations. PMID:2406872

  20. Production of a Blue Pigment (Glaukothalin) by Marine Rheinheimera spp.

    PubMed Central

    Grossart, Hans-Peter; Thorwest, Marc; Plitzko, Inken; Brinkhoff, Thorsten; Simon, Meinhard; Zeeck, Axel

    2009-01-01

    Two ?-Proteobacteria strains, that is, HP1 and HP9, which both produce a diffusible deep blue pigment, were isolated from the German Wadden Sea and from the resund, Denmark, respectively. Both strains affiliate with the genus Rheinheimera. Small amounts of the pigment could be extracted from HP1 grown in a 50 L fermenter and were purified chromatographically. Chemical analysis of the pigment including NMR and mass spectrometry led to a molecular formula of C34H56N4O4 (m.w. 584.85) which has not yet been reported in literature. The molecule is highly symmetrically and consists of two heterocyclic halves to which aliphatic side chains are attached. The pigment has been named glaukothalin due to its blue color and its marine origin (glaukos, gr. = blue, thalatta, gr. = sea). Production of glaukothalin on MB2216 agar plates by our Rheinheimera strains is affected in the presence of other bacterial strains either increasing or decreasing pigment production. The addition of a single amino acid, arginine (5 gl?1), greatly increases pigment production by our Rheinheimera strains. Even though the production of glaukothalin leads to inhibitory activity against three bacterial strains from marine particles, our Rheinheimera isolates are inhibited by various bacteria of different phylogenetic groups. The ecological role of glaukothalin production by Rheinheimera strains, however, remains largely unknown. PMID:20016676

  1. Blue companions of Cepheids

    NASA Technical Reports Server (NTRS)

    Bohm-Vitense, E.; Proffitt, C.

    1985-01-01

    Twenty-one Cepheids, known or suspected to have blue companions, were studied with the International Ultraviolet Explorer satellite. For 13 of them, companions were indeed seen, though they were generally fainter in the UV than expected. For four Population I Cepheids, the suspected companions were not seen. For none of the Population II Cepheids could a companion be detected. The effective temperatures and luminosities of the companions which could be observed are discussed, and the positions of Cepheids and companions in the T(eff) luminosity diagrams are compared with positions expected from stellar evolution calculations.

  2. Flexoelectric blue phases.

    PubMed

    Alexander, G P; Yeomans, J M

    2007-08-10

    We describe the occurrence and properties of liquid crystal phases showing two dimensional splay and bend distortions which are stabilized by flexoelectric interactions. These phases are characterized by regions of locally double splayed order separated by topological defects and are thus analogous to the blue phases of cholesteric liquid crystals. We present a mean-field analysis based upon the Landau-de Gennes Q-tensor theory and construct a phase diagram for flexoelectric structures using analytic and numerical results. We stress the similarities and discrepancies between the cholesteric and flexoelectric cases. PMID:17930865

  3. Hyperspectral image reconstruction using RGB color for foodborne pathogen detection on agar plates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reports the latest development of a color vision technique for detecting colonies of foodborne pathogens grown on agar plates with a hyperspectral image classification model that was developed using full hyperspectral data. The hyperspectral classification model depended on reflectance sp...

  4. EFFECT OF IMPACT STRESS ON MICROBIAL RECOVERY ON AN AGAR SURFACE

    EPA Science Inventory

    Microbial stress due to the impaction of microorganisms onto an agar collection surface was studied experimentally. he relative recovery rates of aerosolized Pseudomonas fluorescens and Micrococcus luteus were determined as a function of the impaction velocity by using a moving a...

  5. A simple agar plate method, using micro-algae, for herbicide bio-assay or detection.

    PubMed

    Wright, S J

    1975-07-01

    A simple, inexpensive method is described for the bio-assay of herbicides using micro-algae growing on agar plates. A result is obtainable in 2 days and the method is suitable for biodetection of herbicide residues, or toxicity studies on soil or aquatic pollutants. PMID:1148432

  6. Radiation survival of murine and human melanoma cells utilizing two assay systems: monolayer and soft agar.

    PubMed Central

    Yohem, K. H.; Slymen, D. J.; Bregman, M. D.; Meyskens, F. L.

    1988-01-01

    The radiation response of murine and human melanoma cells assayed in bilayer soft agar and monolayer was examined. Cells from the murine melanoma Cloudman S91 CCL 53.1 cell line and three human melanoma cell strains (C8146C, C8161, and R83-4) developed in our laboratory were irradiated by single dose X-rays and plated either in agar or on plastic. D0 values were the same within 95% confidence intervals for cells from the human melanoma cell strains C8146C, C8161, and R83-4 but were dissimilar for the murine cell line CCL 53.1 Dq values were different for all cells studied. The shape of the survival curve for all four melanomas was not identical for cells assayed in soft agar versus cells grown on plastic. This would indicate that apparent radiosensitivity was influenced by the method of assay although there were no apparent consistent differences between the curves generated by monolayer or bilayer soft agar assays. PMID:3348949

  7. Applying Agar's Concept of "Languaculture" to Explain Asian Students' Experiences in the Australian Tertiary Context

    ERIC Educational Resources Information Center

    Norris, Lindy; Tsedendamba, Nara

    2015-01-01

    This paper reports part of a broader qualitative case study of Asian students "translation" (Agar, 2006) to study in an Australian university. The paper is concerned with the experiences of eight participants and their involvement in a training programme in the use of language learning strategies (LLS) to support their engagement with…

  8. THE MICROGARDENING COOKBOOK, DIRECTIONS FOR PREPARING DISHES AND TUBES OF STERILE NUTRIENT AGAR.

    ERIC Educational Resources Information Center

    CHANDLER, MARION N.

    THIS BOOKLET WAS PREPARED FOR TEACHER USE IN ASSOCIATION WITH THE ELEMENTARY SCIENCE STUDY UNIT "MICROGARDENING." IT CONTAINS DIRECTIONS FOR PREPARING CULTURE DISHES AND TUBES OF NUTRIENT STERILE AGAR FOR FUNGAL AND/OR BACTERIAL GROWTH. IT INCLUDES (1) LISTS OF NEEDED SUPPLIES AND EQUIPMENT, (2) DIRECTIONS FOR THE PREPARATION AND STERILIZATION OF…

  9. Comparison of the antibacterial activity of chelating agents using the agar diffusion method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agar diffusion assay was used to examine antibacterial activity of 2 metal chelators. Concentrations of 0 to 40 mM of ethylenediaminetetraacetic acid (EDTA) and ethylenediamine-N,N’-disuccinic acid (EDDS) were prepared in 1.0 M potassium hydroxide (KOH). The pH of the solutions was adjusted to 1...

  10. MODIFIED AGAR MEDIUM FOR DETECTING ENVIRONMENTAL SALMONELLAE BY THE MOST-PROBABLE-NUMBER METHOD

    EPA Science Inventory

    Salmonellae in the environment remain a potential source of disease. Low numbers of salmonellae have been detected and enumerated from environmental samples by most probable number methods that require careful colony selection from plated agar medium. A modified xylose lysine bri...

  11. Development of hyperspectral imaging technique for salmonella enteritidis and typhimurium on agar plates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella is a common cause of foodborne disease resulting from the consumption of contaminated food products. Although a direct plating method is widely used for presumptive positive screening of pathogenic Salmonella colonies on agar plates, it is labor-intensive, time-consuming and also prone to...

  12. Mercury in fruiting bodies of Fly Agaric Amanita muscaria (L.: Fr.) Pers. collected from Poland

    NASA Astrophysics Data System (ADS)

    Falandysz, J.; Lipka, K.

    2003-05-01

    Total mercury concentrations were determined in the fruiting bodies of Fly Agaric Amanita muscaria (L.: FL) Pers. and underlying soil substrate collected from several sites in Poland in 1993-2000 to evaluate mercury status as contaminant and bioindicating features of this species. The samples were collected from the spatially distant sites such as: Zaborski Landscape Park, Mierzeja Wiślana Landscape Park, Wdzydzki Landscape Park, Borecka Forest, Tucholskie Forest, Wieluńska Upland, the communities of Gubin, Manowo, Lubiana and Morag. Total mercury content of caps and stalks of Fly agaric varied widely depending on the sites examined. The range of the mean mercury concentrations for all 17 sites was between 96±10 and 1900±1400 ng/g dry wt for the caps and between 6l±32 and 920±760 ng/g dry wt for the stalks, while between 4.4±3.1 and 150±20 ng/g were noted for soil substrate samples from 9 sites examined. Fly agaric independently of the site examined showed relatively good capacity to accumulate total mercury and BCF values varied between 16±10 and 74±15 for the caps and between 11±8 and 42±10 for the stalks. Nevertheless, relatively high bioconcentration potential of mercury by Fly agaric seems to be specific for that species and under soil mercury concentrations noted no bioindication properties of this mushroom could be observed.

  13. Automated agar plate streaker: a linear plater on Society for Biomolecular Sciences standard plates.

    PubMed

    King, Gregory W; Kath, Gary S; Siciliano, Sal; Simpson, Neal; Masurekar, Prakash; Sigmund, Jan; Polishook, Jon; Skwish, Stephen; Bills, Gerald; Genilloud, Olga; Peláez, Fernando; Martín, Jesus; Dufresne, Claude

    2006-09-01

    Several protocols for bacterial isolation and techniques for aerobic plate counting rely on the use of a spiral plater to deposit concentration gradients of microbial suspensions onto a circular agar plate to isolate colony growth. The advantage of applying a gradient of concentrations across the agar surface is that the original microbiological sample can be applied at a single concentration rather than as multiple serial dilutions. The spiral plater gradually dilutes the sample across a compact area and therefore saves time preparing dilutions and multiple agar plates. Commercial spiral platers are not automated and require manual sample loading. Dispensing of the sample volume and rate of gradients are often very limited in range. Furthermore, the spiral sample application cannot be used with rectangular microplates. Another limitation of commercial spiral platers is that they are useful only for dilute, filtered suspensions and cannot plate suspensions of coarse organic particles therefore precluding the use of many kinds of microorganism-containing substrata. An automated agar plate spreader capable of processing 99 rectangular microplates in unattended mode is described. This novel instrument is capable of dispensing discrete volumes of sample in a linear pattern. It can be programmed to dispense a sample suspense at a uniform application rate or across a decreasing concentration gradient. PMID:16844965

  14. Alternative plasticizers for the production of thermo-compressed agar films

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One percent agar (% wt) was dissolved in the deep eutectic solvent (DES), (2-hydroxyethyl) trimethylammonium chloride/urea at a 1:2 molar ratio, and successfully Electrospun into nanofibers. An existing electrospinning set-up, operated at 50 deg C, was adapted for use with an ethanol bath to collect...

  15. A modified micro chamber agar spot slide culture technique for microscopic examination of filamentous fungi.

    PubMed

    Prakash, Peralam Yegneswaran; Bhargava, Kanika

    2016-04-01

    The slide culture technique aids in the study of undisturbed microscopic morphological details of filamentous fungi. The existing methods for setting up of slide culture are quite cumbersome, time-consuming and require elaborate preparation. We describe a modified and easy to perform micro chamber agar spot slide culture technique. PMID:26924158

  16. Investigation of dental alginate and agar impression materials as a brain simulant for ballistic testing.

    PubMed

    Falland-Cheung, Lisa; Piccione, Neil; Zhao, Tianqi; Lazarjan, Milad Soltanipour; Hanlin, Suzanne; Jermy, Mark; Waddell, J Neil

    2016-06-01

    Routine forensic research into in vitro skin/skull/brain ballistic blood backspatter behavior has traditionally used gelatin at a 1:10 Water:Powder (W:P) ratio by volume as a brain simulant. A limitation of gelatin is its high elasticity compared to brain tissue. Therefore this study investigated the use of dental alginate and agar impression materials as a brain simulant for ballistic testing. Fresh deer brain, alginate (W:P ratio 91.5:8.5) and agar (W:P ratio 81:19) specimens (n=10) (11×22×33mm) were placed in transparent Perspex boxes of the same internal dimensions prior to shooting with a 0.22inch caliber high velocity air gun. Quantitative analysis to establish kinetic energy loss, vertical displacement elastic behavior and qualitative analysis to establish elasticity behavior was done via high-speed camera footage (SA5, Photron, Japan) using Photron Fastcam Viewer software (Version 3.5.1, Photron, Japan) and visual observation. Damage mechanisms and behavior were qualitatively established by observation of the materials during and after shooting. The qualitative analysis found that of the two simulant materials tested, agar behaved more like brain in terms of damage and showed similar mechanical response to brain during the passage of the projectile, in terms of energy absorption and vertical velocity displacement. In conclusion agar showed a mechanical and subsequent damage response that was similar to brain compared to alginate. PMID:27131216

  17. Evolutionary consequences of putative intra- and interspecific hybridization in agaric fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agaric fungi of the southern Appalachians including the Great Smoky Mountains National Park are often heterozygous for the rDNA internal transcribed spacer region (ITS) with >42% of collections showing some level of heterozygosity for indels and/or base-pair substitutions. For these collections, int...

  18. Seasonal variation in the biomass and agar yield from Gracilaria cervicornis and Hydropuntia cornea from Brazil.

    PubMed

    Marinho-Soriano, E; Silva, T S; Moreira, W S

    2001-04-01

    Seasonality of biomass and agar yield from two agarophytes (G. cervicornis and H. cornea) was determined. The biomass from G. cervicornis was higher (390 g m-2) during the dry season and lower during the rainy season (129 g m-2). The data analysis for G. cervicornis revealed a significant seasonal variation (P < 0.05). H. cornea did not show a clear seasonal variation and was present only from March to August. The peak in biomass for this species was recorded in April (383 g m-2) and was significantly different from the other months (P < 0.05). The agar yield for G. cervicornis varied from 11% to 20%, with generally higher values recorded during the dry season. The agar yield showed a highly significant variation (P < 0.001). Agar yield from H. cornea ranged from 29% to 41%, with a peak recorded in June. The results above indicate that H. cornea can be considered a good candidate for commercial use. PMID:11272017

  19. A Method for Cell Culture and Maintenance of Ammonia-Oxidizing Archaea in Agar Stab.

    PubMed

    Chu, Yeon-Jin; Lee, Jin-Young; Shin, So-Ra; Kim, Geun-Joong

    2015-12-01

    Ammonia oxidizing archaea (AOA) are predominantly found and closely linked with geochemical cycling of nitrogen in non-extreme habitats. However, these strains have mainly been investigated using liquid cultures of enriched cells. Here, we provide an agar stab as a simple and reliable means of cultivating and maintaining AOA. PMID:26543273

  20. Production of microbial medium from defatted brebra (Milletia ferruginea) seed flour to substitute commercial peptone agar

    PubMed Central

    Andualem, Berhanu; Gessesse, Amare

    2013-01-01

    Objective To investigate and optimize microbial media that substitute peptone agar using brebra seed defatted flour. Methods 'Defatted process, inoculums preparation, evaluation of bacterial growth, preparation of cooked and hydrolyzed media and growth turbidity of tested bacteria were determined. Results Two percent defatted flour was found to be suitable concentration for the growth of pathogenic bacteria: Escherichia coli (ATCC 25922) (E. coli), Pseudomonas aeruginosa (ATCC 27853), Salmonella (NCTC 8385) and Shigella flexneri (ATCC 12022) (S. flexneri), while 3% defatted flour was suitable for Staphylococcus aureus (ATCC 25923) (S. aureus). E. coli (93±1) and S. flexneri (524±1) colony count were significantly (P≤0.05) greater in defatted flour without supplement than in supplemented medium. E. coli [(3.72×109±2) CFU/mL], S. aureus [(7.4×109±2) CFU/mL], S. flexneri [(4.03×109±2) CFU/mL] and Salmonella [(2.37×109±1) CFU/mL] in non-hydrolyzed sample were statistically (P≤0.05) greater than hydrolyzed one and commercial peptone agar. Colony count of Salmonella [(4.55×109±3) CFU/mL], S. flexneri [(5.40×109±3) CFU/mL] and Lyesria moncytogenes (ATCC 19116) [(5.4×109±3) CFU/mL] on raw defatted flour agar was significantly (P≤0.05) greater than cooked defatted flour and commercial peptone agar. Biomass of E. coli, S. aureus, Salmonella and Enterococcus faecalis in non-hydrolyzed defatted flour is highly increased over hydrolyzed defatted flour and commercial peptone broth. Conclusions The defatted flour agar was found to be better microbial media or comparable with peptone agar. The substances in it can serve as sources of carbon, nitrogen, vitamins and minerals that are essential to support the growth of microorganisms without any supplements. Currently, all supplements of peptone agar are very expensive in the market. PMID:24075344

  1. Blue ocean leadership.

    PubMed

    Kim, W Chan; Mauborgne, Renée

    2014-05-01

    Ten years ago, two INSEAD professors broke ground by introducing "blue ocean strategy," a new model for discovering uncontested markets that are ripe for growth. In this article, they apply their concepts and tools to what is perhaps the greatest challenge of leadership: closing the gulf between the potential and the realized talent and energy of employees. Research indicates that this gulf is vast: According to Gallup, 70% of workers are disengaged from their jobs. If companies could find a way to convert them into engaged employees, the results could be transformative. The trouble is, managers lack a clear understanding of what changes they could make to bring out the best in everyone. Here, Kim and Mauborgne offer a solution to that problem: a systematic approach to uncovering, at each level of the organization, which leadership acts and activities will inspire employees to give their all, and a process for getting managers throughout the company to start doing them. Blue ocean leadership works because the managers' "customers"-that is, the people managers oversee and report to-are involved in identifying what's effective and what isn't. Moreover, the approach doesn't require leaders to alter who they are, just to undertake a different set of tasks. And that kind of change is much easier to implement and track than changes to values and mind-sets. PMID:24956870

  2. Project Blue Revolution

    SciTech Connect

    Takahashi, P.K.

    1996-12-01

    In June of 1992, the National Science Foundation and National Oceanic and Atmospheric Administration sponsored a strategic planning workshop, involving 35 ocean technologists representing the Atlantic, Gulf, and Pacific marine communities, to develop a proactive plan for the commercialization of national Exclusive Economic Zone resources. This meeting was the culmination of a series of gatherings held over the past decade, each treating specific ocean applications. The blue-ribbon panel recommended the consolidation of all ocean resource development activities within the federal government,a nd named the Department of Commerce as the ideal agency to manage this office, congressional oversight hearings to reestablish ocean priorities,a nd a broad spectrum of major ocean enterprises for the 21st century. During this same period, an international workshop was held in Hawaii with 50 invited specialists from six countries to discuss the merits of a cooperative program identified as Project Blue Revolution. The attendees determined that a 1 ha (100,000 sq ft) floating platform powered by ocean thermal energy conversion and at a projected cost of $500,000,000 to serve as an incubator for facilitating the commercialization of ocean resources and supporting marine science research, was a feasible venture.

  3. Effect of impact stress on microbial recovery on an agar surface.

    PubMed Central

    Stewart, S L; Grinshpun, S A; Willeke, K; Terzieva, S; Ulevicius, V; Donnelly, J

    1995-01-01

    Microbial stress due to the impaction of microorganisms onto an agar collection surface was studied experimentally. The relative recovery rates of aerosolized Pseudomonas fluorescens and Micrococcus luteus were determined as a function of the impaction velocity by using a moving agar slide impactor operating over a flow rate range from 3.8 to 40 liters/min yielding impaction velocities from 24 to 250 m/s. As a reference, the sixth stage of the Andersen Six-Stage Viable Particle Sizing Sampler was used at its operating flow rate of 28.3 liters/min (24 m/s). At a collection efficiency of close to 100% for the agar slide impactor, an increase in sampling flow rate and, therefore, in impaction velocity produced a significant decline in the percentage of microorganisms recovered. Conversely, when the collection efficiency was less than 100%, greater recovery and lower injury rates occurred. The highest relative rate of recovery (approximately 51% for P. fluorescens and approximately 62% for M. luteus) was obtained on the complete (Trypticase soy agar) medium at 40 and 24 m/s (6.4 and 3.8 liters/min), respectively. M. luteus demonstrated less damage than P. fluorescens, suggesting the hardy nature of the gram-positive strain versus that of the gram-negative microorganism. Comparison of results from the agar slide and Andersen impactors at the same sampling velocity showed that recovery and injury due to collection depends not only on the magnitude of the impaction velocity but also on the degree to which the microorganisms may be embedded in the collection medium.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7747946

  4. Differentiating non-0157:H7 STEC serogroups from ground beef plated on agar media by hyperspetral imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: The development of an assay to detect and confirm a positive non-O157:H7 isolate is challenging when mixed morphologically results are obtained from the serogroups growing on Rainbow agar. Rainbow agar is only claimed by the manufacturer to be very specific for E.coli O157:H7 strain...

  5. Effect of lignin on water vapor barrier, mechanical, and structural properties of agar/lignin composite films.

    PubMed

    Shankar, Shiv; Reddy, Jeevan Prasad; Rhim, Jong-Whan

    2015-11-01

    Biodegradable composite films were prepared using two renewable resources based biopolymers, agar and lignin alkali. The lignin was used as a reinforcing material and agar as a biopolymer matrix. The effect of lignin concentration (1, 3, 5, and 10wt%) on the performance of the composite films was studied. In addition, the mechanical, water vapor barrier, UV light barrier properties, FE-SEM, and TGA of the films were analyzed. The agar/lignin films exhibited higher mechanical and UV barrier properties along with lower water vapor permeability compared to the neat agar film. The FTIR and SEM results showed the compatibility of lignin with agar polymer. The swelling ratio and moisture content of agar/lignin composite films were decreased with increase in lignin content. The thermostability and char content of agar/lignin composite films increased with increased lignin content. The results suggested that agar/lignin films have a potential to be used as a UV barrier food packaging material for maintaining food safety and extending the shelf-life of the packaged food. PMID:26271435

  6. Agar-block microcosms for controlled plant tissue decomposition by aerobic fungi.

    PubMed

    Schilling, Jonathan S; Jacobson, K Brook

    2011-01-01

    The two principal methods for studying fungal biodegradation of lignocellulosic plant tissues were developed for wood preservative testing (soil-block; agar-block). It is well-accepted that soil-block microcosms yield higher decay rates, fewer moisture issues, lower variability among studies, and higher thresholds of preservative toxicity. Soil-block testing is thus the more utilized technique and has been standardized by American Society for Testing and Materials (ASTM) (method D 1413-07). The soil-block design has drawbacks, however, using locally-variable soil sources and in limiting the control of nutrients external (exogenous) to the decaying tissues. These drawbacks have emerged as a problem in applying this method to other, increasingly popular research aims. These modern aims include degrading lignocellulosics for bioenergy research, testing bioremediation of co-metabolized toxics, evaluating oxidative mechanisms, and tracking translocated elements along hyphal networks. Soil-blocks do not lend enough control in these applications. A refined agar-block approach is necessary. Here, we use the brown rot wood-degrading fungus Serpula lacrymans to degrade wood in agar-block microcosms, using deep Petri dishes with low-calcium agar. We test the role of exogenous gypsum on decay in a time-series, to demonstrate the utility and expected variability. Blocks from a single board rip (longitudinal cut) are conditioned, weighed, autoclaved, and introduced aseptically atop plastic mesh. Fungal inoculations are at each block face, with exogenous gypsum added at interfaces. Harvests are aseptic until the final destructive harvest. These microcosms are designed to avoid block contact with agar or Petri dish walls. Condensation is minimized during plate pours and during incubation. Finally, inoculum/gypsum/wood spacing is minimized but without allowing contact. These less technical aspects of agar-block design are also the most common causes of failure and the key source of variability among studies. Video publication is therefore useful in this case, and we demonstrate low-variability, high-quality results. PMID:21339715

  7. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus.

    PubMed

    Laarhoven, Bob; Elissen, H J H; Temmink, H; Buisman, C J N

    2016-01-01

    An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv). The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml), 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin). With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates. PMID:26937632

  8. Agar Sediment Test for Assessing the Suitability of Organic Waste Streams for Recovering Nutrients by the Aquatic Worm Lumbriculus variegatus

    PubMed Central

    Laarhoven, Bob; Elissen, H. J. H.; Temmink, H.; Buisman, C. J. N.

    2016-01-01

    An agar sediment test was developed to evaluate the suitability of organic waste streams from the food industry for recovering nutrients by the aquatic worm Lumbriculus variegatus (Lv). The effects of agar gel, sand, and food quantities in the sediment test on worm growth, reproduction, and water quality were studied. Agar gel addition ameliorated growth conditions by reducing food hydrolysis and altering sediment structure. Best results for combined reproduction and growth were obtained with 0.6% agar-gel (20 ml), 10 g. fine sand, 40 g. coarse sand, and 105 mg fish food (Tetramin). With agar gel, ingestion and growth is more the result of addition of food in its original quality. Final tests with secondary potato starch sludge and wheat bran demonstrated that this test is appropriate for the comparison of solid feedstuffs and suspended organic waste streams. This test method is expected to be suitable for organic waste studies using other sediment dwelling invertebrates. PMID:26937632

  9. Melanoma and satellite blue papule.

    PubMed

    Oliveira, André; Arzberger, Edith; Massone, Cesare; Zalaudek, Iris; Fink-Puches, Regina; Hofmann-Wellenhof, Rainer

    2014-07-01

    The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis. PMID:25126462

  10. Melanoma and satellite blue papule

    PubMed Central

    Oliveira, André; Arzberger, Edith; Massone, Cesare; Zalaudek, Iris; Fink-Puches, Regina; Hofmann-Wellenhof, Rainer

    2014-01-01

    The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis. PMID:25126462

  11. Synthesis and applications of poly(2-hydroxyethylmethacrylate) grafted agar: a microwave based approach.

    PubMed

    Rani, G Usha; Mishra, Sumit; Pathak, Gopal; Jha, Usha; Sen, Gautam

    2013-10-01

    Synthesis of graft copolymers under the influence of microwave radiation alone is a rapid, efficient, clean, cheap, convenient, energy-saving and green method. Grafting of poly(2-hydroxyethylmethacrylate) on agar backbone was carried out under the influence of microwave radiation. The synthesis is optimized in terms of percentage grafting and intrinsic viscosity, by varying the microwave irradiation time and monomer (2-hydroxyethylmethacrylate) concentration. The synthesized graft copolymers have been characterized by intrinsic viscosity measurement, FTIR spectroscopy, UV-spectroscopy, elemental analysis (C, H, N, & S), thermal studies and scanning electron microscopy (SEM). Flocculation efficacy of the synthesized graft copolymers was studied in 0.25% kaolin and 1% coal fine suspension, through 'jar test' procedure. Further, flocculation efficacy of the best grade, coagulant (alum) and agar were studied for possible application in remediation of metals from river water. PMID:23850679

  12. Enumeration of Fecal Clostridium perfringens Spores in Egg Yolk-Free Tryptose-Sulfite-Cycloserine Agar

    PubMed Central

    Hauschild, A. H. W.; Hilsheimer, R.; Griffith, D. W.

    1974-01-01

    The Shahidi-Ferguson perfringens, tryptose-sulfite-cycloserine (TSC), and egg yolk-free TSC agars have been tested for their suitability to enumerate fecal spores of Clostridium perfringens. When these spores comprised at least 20% of the total anaerobe spores, equally accurate counts were obtained in the three media. With lower ratios of C. perfringens spores, the most accurate counts were obtained in egg yolk-free TSC agar. The median C. perfringens spore count of 60 normal fecal specimens was log 3.4/g. A nonmotile, sulfite- and nitrate-reducing Clostridium, not identifiable with any known clostridial species, was isolated from 14 out of 60 fecal specimans. It was not differentiated from C. perfringens in the nitrite motility test, but could be distinguished by its inability to liquefy gelatin. PMID:4363369

  13. Co-precipitation with PVP and Agar to Improve Physicomechanical Properties of Ibuprofen

    PubMed Central

    Maghsoodi, Maryam; Kiafar, Farhad

    2013-01-01

    Objective(s) : Ibuprofen is a problematic drug in tableting due to its viscoelastic properties. Additionally its high cohesivity results in low flowability. In this study, co-precipitation of ibuprofen with varying concentration of agar and PVP to optimize properties of Ibuprofen was carried out. Materials and Methods: Co-precipitates of ibuprofen- PVP or agar were prepared by solvent evaporation technique under vacuum condition. Differential scanning calorimetry (DSC), X -ray diffraction of powder (XRDP) and FT-IR spectroscopy were used to investigate the solid state characteristics of the co-precipitates. The dissolution behavior, flowability, particle size and compaction properties of various batches were also studied. Results: Co-precipitation of drug with agar led to a change in habit from needle to plate shape crystals, while drug –PVP co-precipitates had agglomerated structure and consisted of numerous crystals which had been aggregated together. The co-precipitates showed improved flow properties compared with ibuprofen alone. Precipitation of ibuprofen with these additives led to modification in the dissolution of the drug. Agar in 1% w/w improved slightly the dissolution rate of drug while PVP had a negative impact and led to reduction in the dissolution rate of drug to less than that of pure drug. The all obtained co-precipitates exhibited significantly improved tableting behavior compared with drug crystals alone. This may be due to this fact that, the polymer covering the drug particles increases and changes the nature of the surface area available for interparticulate bonds between particles. DSC, XRDP and FT-IR experiments showed that drug particles, in co-precipitates samples, did not undergo polymorphic modifications. Conclusion: The study highlights the influence of polymeric additives on crystallization process leading to modified performance. PMID:24250936

  14. Co-precipitation with PVP and Agar to Improve Physicomechanical Properties of Ibuprofen

    PubMed Central

    Maghsoodi, Maryam; Kiafar, Farhad

    2013-01-01

    Objective(s) : Ibuprofen is a problematic drug in tableting due to its viscoelastic properties. Additionally its high cohesivity results in low flowability. In this study, co-precipitation of ibuprofen with varying concentration of agar and PVP to optimize properties of Ibuprofen was carried out. Materials and Methods: Co-precipitates of ibuprofen- PVP or agar were prepared by solvent evaporation technique under vacuum condition. Differential scanning calorimetry (DSC), X -ray diffraction of powder (XRDP) and FT-IR spectroscopy were used to investigate the solid state characteristics of the co-precipitates. The dissolution behavior, flowability, particle size and compaction properties of various batches were also studied. Results: Co-precipitation of drug with agar led to a change in habit from needle to plate shape crystals, while drug –PVP co-precipitates had agglomerated structure and consisted of numerous crystals which had been aggregated together. The co-precipitates showed improved flow properties compared with ibuprofen alone. Precipitation of ibuprofen with these additives led to modification in the dissolution of the drug. Agar in 1% w/w improved slightly the dissolution rate of drug while PVP had a negative impact and led to reduction in the dissolution rate of drug to less than that of pure drug. The all obtained co-precipitates exhibited significantly improved tableting behavior compared with drug crystals alone. This may be due to this fact that, the polymer covering the drug particles increases and changes the nature of the surface area available for interparticulate bonds between particles. DSC, XRDP and FT-IR experiments showed that drug particles, in co-precipitates samples, did not undergo polymorphic modifications. Conclusion: The study highlights the influence of polymeric additives on crystallization process leading to modified performance. PMID:24250942

  15. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus

    PubMed Central

    Cold, Emma R.; Freyria, Nastasia J.; Martínez Martínez, Joaquín; Fernández Robledo, José A.

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham’s F12–5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham’s F12–5% FBS– 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham’s F12–5% FBS– 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications. PMID:27149378

  16. Agar Plate Method for Detection and Enumeration of Alkylbenzenesulfonate-Degrading Microorganisms

    PubMed Central

    Ohwada, Kouichi

    1975-01-01

    A simple method for detection and enumeration of alkylbenzenesulfonate (ABS)-degrading microorganisms by using agar plates was developed and used in microbiological studies of coastal marine and polluted river waters. The method depends upon the color responses of neutral red in alkaline medium. Neutral red changes from pink, when it enters into ABS micelles, to yellow, when the ABS is degraded, and does not form micelles. When neutral red-tris(hydroxymethyl)-aminomethane buffer solution and then cationic surfactant solution were sprayed onto the agar surface of ABS-nutrient agar cultures, transparent haloes appeared around the colonies of ABS-degrading microorganisms against a pink background. Viable counts of ABS-degrading bacteria isolated from both seawater and freshwater environments were considerably higher in polluted waters than in less polluted areas. Viable counts of ABS-degrading bacteria averaged 1.5 × 105/ml in samples from the surface water of polluted Tokyo Bay and 3.0 × 104/ml in samples from the surface water of polluted Tamagawa River but were fewer in number in samples from less polluted waters. Images PMID:234155

  17. Mode of Action of an Inhibitor from Agar on Growth and Hemagglutination of Group A Arboviruses

    PubMed Central

    Colón, Julio I.; Idoine, Jane B.; Brand, Orville M.; Costlow, Richard D.

    1965-01-01

    Colón, Julio I. (Fort Detrick, Frederick, Md.), Jane B. Idoine, Orville M. Brand, and Richard D. Costlow. Mode of action of an inhibitor from agar on growth and hemagglutination of group A arboviruses. J. Bacteriol. 90:172–179. 1965.—A polysaccharide obtained from agar, and having properties similar to a previously described sulfated polysaccharide, was observed to inhibit growth and hemagglutination of some group A arboviruses. The evidence presented confirms that the inhibitory activity, in part, is the result of direct interaction between the agar polysaccharide (AP) and free virus particles. Additional evidence indicates that inhibition of viral growth also occurs as the result of interaction between AP and the chick-fibroblast cells used for propagation of the virus. The possibility was considered, therefore, that at least two different inhibitors could be present in AP—one that reacts directly with the virus particle and another that reacts with host cells. AP does not induce the production of interferon in the test system used. PMID:16562015

  18. Alternative plasticizers for the production of thermo-compressed agar films.

    PubMed

    Sousa, Ana M M; Souza, Hilia K S; Liu, LinShu; Gonalves, Maria P

    2015-05-01

    Agar films were produced by thermo-compression using choline chloride (ChCl) as a plasticizer with urea. The three solid components were mixed together with the salt and urea (minor components) added to agar (main component) according to a fixed mass ratio of, respectively, 1.16:1:5. A central composite rotatable design (CCRD) with three parameters, 2(3), was used to evaluate the effects of temperature (X1; C), time (X2; min) and applied load (X3; kN) of heat-pressing on the maximum tensile strength (TS) of the films (Y; MPa). Mixtures of urea and agar prepared at a mass ratio of 1:5 did not form homogeneous films suggesting the important plasticizing role of the salt. Heat-pressing the mixtures at more draconian conditions led to much darker and opaque films, with better mechanical resistance (higher values of TS). The most resistant film (? 15 MPa) was obtained at 140C, 20 min and 176 kN. Selected films, including the optimal, showed similar water sorption profiles and close values of water vapor permeability (? 2.5-3.7 10(-9)gm(-1)s(-1)Pa(-1)). The fracture behavior and mechanical properties of the films were greatly affected by additional water plasticization when the films were stored at different conditions of relative humidity. PMID:25727746

  19. Use of an agar culture technique for establishing lymphoid cell lines from Marek's disease lymphomas.

    PubMed

    Payne, L N; Howes, K; Rennie, M; Bumstead, J M; Kidd, A W

    1981-12-01

    Lymphoblastoid cell lines derived from Marek's disease (MD) lymphomas have been established with difficulty by a number of workers. We have compared with conventional liquid culture methods the efficiency of a new technique for establishing lymphoid cell lines in which lymphoma cells were cultured initially in agar medium. Cells from 39/79 lymphomas gave rise to loose lymphoid colonies in the seeded agar after 7 days' incubation at 41 degrees C. Two types of macrophage colony also developed. When lymphoid colonies in agar were transferred to liquid culture, 23/39 gave rise to permanent lymphoid cell lines, compared with 8/33 comparable cultures initiated in liquid medium. Twenty-nine new cell lines have been developed from Rhode Island Red, line 6 and line 7 chickens. All carry T-cell markers and the MD tumour-associated surface antigen (MATSA) and showed variable but low responsiveness to lectin mitogens. The new cell lines, when first established, consisted mainly of small, lymphocytoid cells, but, after varying times, these changed into typical lymphoblastoid lines and an increased expression of an embryonic antigen was associated with this change. The lymphocytoid line cells were more slowly growing and density-dependent than were the lymphoblastoid cells, and lymphocytoid lines grew better at 41 degrees C and lymphoblastoid lines better at 37 degrees C. MD virus could be rescued from some of the lines but others appeared to be true non-producers. PMID:7199514

  20. Evaluation of cephamycins as supplements to selective agar for detecting Campylobacter spp. in chicken carcass rinses.

    PubMed

    Chon, Jung-Whan; Kim, Young-Ji; Kim, Hong-Seok; Kim, Dong-Hyeon; Kim, Hyunsook; Song, Kwang-Young; Sung, Kidon; Seo, Kun-Ho

    2016-04-16

    Although cefoperazone is the most commonly used antibiotic in Campylobacter-selective media, the distribution of cefoperazone-resistant bacteria such as extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli is increasing. Here we evaluated the potential of cephamycins for use as supplements to improve modified charcoal-cefoperazone-deoxycholate agar (mCCDA) by replacing cefoperazone with the same concentrations (32mg/L) of cefotetan (modified charcoal-cefotetan-deoxycholate agar, mCCtDA) and cefoxitin (modified charcoal-cefoxitin-deoxycholate agar, mCCxDA). In chicken carcass rinse samples, the number of mCCDA plates detecting for Campylobacter (18/70, 26%) was significantly lower than that of mCCtDA (42/70, 60%) or mCCxDA plates (40/70, 57%). The number of mCCDA plates (70/70, 100%) that were contaminated with non-Campylobacter species was significantly higher than that of mCCtDA (20/70, 29%) or mCCxDA plates (21/70, 30%). The most common competing species identified using mCCDA was ESBL-producing E. coli, while Pseudomonas species frequently appeared on mCCtDA and mCCxDA. PMID:26915052

  1. How do microorganisms influence trace element uptake by plants? Screening in an agar model rhizosphere.

    NASA Astrophysics Data System (ADS)

    Marchetti, M.; Robinson, B. H.; Evangelou, M. W. H.; Vachey, A.; Schwitzguebel, J. P.; Bernier-Latmani, R.; Schulin, R.

    2009-04-01

    Trace elements (TE) are essential for humans and plants, but they may be toxic if their concentration is too high. For this reason, the management of TE in soils is very important. In some cases it may be necessary to increase the uptake of nutrients or TE by plants, for example in a biofortification perspective. Conversely, in some other cases TE uptake by plants should be decreased, for instance to avoid heavy metals entering the food chain via edible crops. Microorganisms living in the rhizosphere affect trace element (TE) uptake by plants. However, due to the complexity of this space and the variety of microorganisms that occur there, it is difficult to isolate the effect of any particular strain. To overcome this hurdle, we developed a system in which we grew plants under sterile conditions in agar and inoculated their rhizosphere with a single, well-defined microbial strain. For many years, agar has been used as a growth substrate for microorganisms and plant tissues. It is cheap, easy to use, and can be autoclaved to ensure its sterility. Because of its widespread use, an experiment conducted using this substrate can be reproduced under the same conditions in any laboratory. In contrast to soil, there is little interaction between the trace elements and the agar matrix. There are many studies investigating the influence of microorganisms on TE uptake by plants. However, so far only a small variety of microorganisms has been tested on few plant species. Therefore, the first objective of our research was to develop a method to rapidly screen a large variety of microorganisms on various plant species. Once this goal was achieved, we sought to study the effect of single, well-defined microbial strains on TE uptake by sunflower and wheat. The substrate for plants growth was a 10% agar solution prepared with modified Hoagland's solution and a TE solution containing 1 mg/kg Pb and molar equivalents of Cu, Ni and Zn. The agar solution was autoclaved and poured into sterile, transparent plastic boxes, whose lid was equipped with a filter allowing gas exchanges without contamination by external microorganisms. The seed surface was sterilised and the plants grew one week in agar before their rhizosphere was inoculated with LB broth containing a pure bacterial strain or agar plugs colonized by fungal hyphae. We tested 14 strains, with 5 replicates per treatment and a control where the system was inoculated with sterile LB broth. The plants grew for 2 weeks in a climate chamber and their shoots were analysed for their TEs by ICP-OES. Samples of agar and roots were collected to confirm microbial colonization of the rhizosphere, respectively sterile conditions in the control treatments. Concerning the method development, the plants grew without visible toxicity in all the boxes, and the analysis of root and agar samples indicated that the controls were sterile and the strains inoculated were growing along the roots. More than 90% of the TE and nutrients added to the system were in the liquid fraction of the agar medium, thus available for root uptake. The screening showed that the microorganisms in general decreased TE uptake by wheat and sunflower, although some of them had an opposite effect on the plants. However, with the same plant species, the microorganisms had a consistent effect on all TE tested, i.e. a given single strain caused the same effect (increase or decrease of TE uptake) on all TE tested. In sunflower, 3 microorganisms (Paenibacillus polymyxa, Pythium ultimum and Rhizoctonia solani) decreased Cu and Zn uptake by 50% compared to the control treatment. These three species are common soil microorganisms. All three are known to exude auxin, a phytohormone. This hormone can modify root morphology and physiology and thus may affect TE uptake by plants. R. solani and P. ultimum are root pathogens. Their effect was opposite to what we expected. If roots are damaged, TE should have flooded into the plant and accumulate in the tissues, but this was not the case. One explanation could be the biosorption of TE by these microorganisms, reducing the uptake by plant. Conversely to sunflower, none of the microorganisms tested showed a significant effect on TE uptake by wheat. With our research, we created an agar system allowing the screening of several microbial strains for their effect on plant TE uptake. Future work will involve screening of several other strains in a wide range of conditions in agar. A method validation with a pot experiment is also needed, as some interactions in this artificial rhizosphere may be different from those that would take place in soil. We will also pursue the investigation of two interesting mechanisms revealed by the screening: the effect of pathogens and phytohormone-exuding microorganisms on TE uptake by plants.

  2. A rapid agar-diffusion test for quantifying the toxic effects of copper on microorganisms.

    PubMed

    Rzycki, H

    1992-01-01

    The rapid agar diffusion test for quantifying the toxic effects of copper on microorganisms was elaborated. The assay was run in standard Petri dishes containing Czapek Solution Agar (Difco). Immediately after inoculation with the organism tested 3.2 mm diameter wells were punched in the agar. Wells were filled (20 microliters) with distilled water (control) and a range of solutions containing 128 to 4096 ppm Cu2+ (as CuSO4). After incubation (2-5 days, 26 degrees C) the diameters of Cu-inhibition zones were measured. Cu-sensitivity indices (ICu's) were calculated according to the formula: ICu = a2/(3.2-b), where: a--slope of the linear regression equation: log [Cu] (x)--inhibition zone diameter (y), b--intercept of the same equation. Additionally for characterization of Cu-sensitivity of the organism tested the predicted highest non-inhibitory Cu concentration (10c) was calculated, where: c = (3.2-b)/a. Both ICu's and adjusted average diameters of Cu-inhibition zones characterized well the Cu-sensitivity in organisms tested, as indicated by the statistical analyses. ICu's correlated very well (negative correlation) with 50% effective doses (Ed50's) of Cu2+ for mycelial growth of Cylindrocarpon destructans. The applicability of the elaborated assay in ecotoxicological studies was discussed. PMID:1283491

  3. New agar microspheres for the separation and purification of natural products.

    PubMed

    Ge, Chunling; Hu, Yu; Zhang, Fan; Lv, Yongqin; Tan, Tianwei

    2014-11-01

    A new type of agar chromatography media has been prepared with a yield over 80% using a water-in-oil emulsion technique. These microspheres have regular spherical shapes and particle diameters in the range 40-165 μm (average ∼90 μm). Cross-linking of the resulting agar microspheres with epichlorohydrin and 1,4-butanediol diglycidyl ether enhanced their mechanical and thermal stability. The alkaline conditions used during the cross-linking reaction also decreased the content of ionized sulfate groups of the polysaccharide, thus reducing the nonspecific adsorption of positively charged molecules. The cross-linked agar microspheres were functionalized with (i) branched poly(ethyleneimine) to obtain a stationary phase useful for the separation of proteins in an anion-exchange mode and (ii) with poly-β-cyclodextrin enabling direct isolation and purification of puerarin from a crude extract of Radix puerariae. Using a 23.5 mL column loaded with 20 mg extract (0.85 mg/mL gel), puerarin with a purity of 96% was recovered with a yield of 86%. PMID:25156195

  4. Isolation of Clostridium difficile from faecal specimens--a comparison of chromID C. difficile agar and cycloserine-cefoxitin-fructose agar.

    PubMed

    Carson, Kerry C; Boseiwaqa, Lusiana V; Thean, Sara K; Foster, Niki F; Riley, Thomas V

    2013-09-01

    The culture of toxigenic Clostridium difficile from stool specimens is still seen as the gold standard for the laboratory diagnosis of C. difficile infection (CDI). bioMérieux have released ChromID Cdiff chromogenic agar (CDIF) for the isolation and identification of C. difficile in 24 h. In this study, we compared CDIF to pre-reduced cycloserine-cefoxitin-fructose agar with sodium taurocholate (TCCFA) in the examination of glutamate dehydrogenase-positive faecal specimens that were either GeneOhm positive or negative, using direct culture or culture following alcohol shock. Direct culture on CDIF had a sensitivity of 100 % and recovery of 94 % while for TCCFA these were 87 % and 82 %, respectively. For GeneOhm-positive alcohol-shocked faecal samples, sensitivity and recovery on CDIF was similar to direct culture while on TCCFA they were about 10 % higher. For direct culture, there was a significant difference between growth on CDIF at 24 h and TCCFA at 48 h (P = 0.001) and between the two media at 48 h (P<0.001). A total of 142 strains of C. difficile were recovered in pure culture from all GeneOhm-positive samples used in this study and 11 (7.7 %) of these were A(-)B(-)CDT(-) and may represent mixed infections of toxigenic and non-toxigenic C. difficile. The most dominant ribotype was UK 014 (14.7 %) followed by 002 (11.9 %) and 020 (11.9 %), and 36 % of toxigenic isolates, including an A(-)B(+)CDT(-) strain, could not be assigned a UK ribotype. CDIF outperformed pre-reduced TCCFA by negating the need for alcohol shock treatment and by giving a time saving of 24 h in the isolation of C. difficile. CDIF plates were also more selective than TCCFA and C. difficile colonies were easy to identify and subculture prior to strain typing. PMID:23579394

  5. Blue ellipticals in compact groups

    NASA Technical Reports Server (NTRS)

    Zepf, Stephen E.; Whitmore, Bradley C.

    1990-01-01

    By studying galaxies in compact groups, the authors examine the hypothesis that mergers of spiral galaxies make elliptical galaxies. The authors combine dynamical models of the merger-rich compact group environment with stellar evolution models and predict that roughly 15 percent of compact group ellipticals should be 0.15 mag bluer in B - R color than normal ellipticals. The published colors of these galaxies suggest the existence of this predicted blue population, but a normal distribution with large random errors can not be ruled out based on these data alone. However, the authors have new ultraviolet blue visual data which confirm the blue color of the two ellipticals with blue B - R colors for which they have their own colors. This confirmation of a population of blue ellipticals indicates that interactions are occurring in compact groups, but a blue color in one index alone does not require that these ellipticals are recent products of the merger of two spirals. The authors demonstrate how optical spectroscopy in the blue may distinguish between a true spiral + spiral merger and the swallowing of a gas-rich system by an already formed elliptical. The authors also show that the sum of the luminosity of the galaxies in each group is consistent with the hypothesis that the final stage in the evolution of compact group is an elliptical galaxy.

  6. Blue moons and Martian sunsets.

    PubMed

    Ehlers, Kurt; Chakrabarty, Rajan; Moosmüller, Hans

    2014-03-20

    The familiar yellow or orange disks of the moon and sun, especially when they are low in the sky, and brilliant red sunsets are a result of the selective extinction (scattering plus absorption) of blue light by atmospheric gas molecules and small aerosols, a phenomenon explainable using the Rayleigh scattering approximation. On rare occasions, dust or smoke aerosols can cause the extinction of red light to exceed that for blue, resulting in the disks of the sun and moon to appear as blue. Unlike Earth, the atmosphere of Mars is dominated by micron-size dust aerosols, and the sky during sunset takes on a bluish glow. Here we investigate the role of dust aerosols in the blue Martian sunsets and the occasional blue moons and suns on Earth. We use the Mie theory and the Debye series to calculate the wavelength-dependent optical properties of dust aerosols most commonly found on Mars. Our findings show that while wavelength selective extinction can cause the sun's disk to appear blue, the color of the glow surrounding the sun as observed from Mars is due to the dominance of near-forward scattering of blue light by dust particles and cannot be explained by a simple, Rayleigh-like selective extinction explanation. PMID:24663457

  7. Blue-fluorescent antibodies.

    PubMed

    Simeonov, A; Matsushita, M; Juban, E A; Thompson, E H; Hoffman, T Z; Beuscher, A E; Taylor, M J; Wirsching, P; Rettig, W; McCusker, J K; Stevens, R C; Millar, D P; Schultz, P G; Lerner, R A; Janda, K D

    2000-10-13

    The forte of catalytic antibodies has resided in the control of the ground-state reaction coordinate. A principle and method are now described in which antibodies can direct the outcome of photophysical and photochemical events that take place on excited-state potential energy surfaces. The key component is a chemically reactive optical sensor that provides a direct report of the dynamic interplay between protein and ligand at the active site. To illustrate the concept, we used a trans-stilbene hapten to elicit a panel of monoclonal antibodies that displayed a range of fluorescent spectral behavior when bound to a trans-stilbene substrate. Several antibodies yielded a blue fluorescence indicative of an excited-state complex or "exciplex" between trans-stilbene and the antibody. The antibodies controlled the isomerization coordinate of trans-stilbene and dynamically coupled this manifold with an active-site residue. A step was taken toward the use of antibody-based photochemical sensors for diagnostic and clinical applications. PMID:11030644

  8. Blue-Fluorescent Antibodies

    NASA Astrophysics Data System (ADS)

    Simeonov, Anton; Matsushita, Masayuki; Juban, Eric A.; Thompson, Elizabeth H. Z.; Hoffman, Timothy Z.; Beuscher, Albert E.; Taylor, Matthew J.; Wirsching, Peter; Rettig, Wolfgang; McCusker, James K.; Stevens, Raymond C.; Millar, David P.; Schultz, Peter G.; Lerner, Richard A.; Janda, Kim D.

    2000-10-01

    The forte of catalytic antibodies has resided in the control of the ground-state reaction coordinate. A principle and method are now described in which antibodies can direct the outcome of photophysical and photochemical events that take place on excited-state potential energy surfaces. The key component is a chemically reactive optical sensor that provides a direct report of the dynamic interplay between protein and ligand at the active site. To illustrate the concept, we used a trans-stilbene hapten to elicit a panel of monoclonal antibodies that displayed a range of fluorescent spectral behavior when bound to a trans-stilbene substrate. Several antibodies yielded a blue fluorescence indicative of an excited-state complex or ``exciplex'' between trans-stilbene and the antibody. The antibodies controlled the isomerization coordinate of trans-stilbene and dynamically coupled this manifold with an active-site residue. A step was taken toward the use of antibody-based photochemical sensors for diagnostic and clinical applications.

  9. AgarTrap-mediated genetic transformation using intact gemmae/gemmalings of the liverwort Marchantia polymorpha L.

    PubMed

    Tsuboyama-Tanaka, Shoko; Kodama, Yutaka

    2015-03-01

    The dioecious liverwort, Marchantia polymorpha L., is an emerging model plant. Various molecular biological techniques have been optimized for M. polymorpha for the past several years, and recently we reported a simplified Agrobacterium-mediated transformation method using sporelings (immature thalli from spores) of M. polymorpha. This method, termed AgarTrap (Agar-utilized Transformation with Pouring Solutions), completed by exchanging appropriate solutions on a single Petri dish to produce a sufficient number of independent transgenic sporelings. However, because spores are produced by crosses between males and females, the genetic backgrounds of resulting transgenic sporelings are not uniform. To easily produce transgenic liverworts with a uniform genetic background using AgarTrap, we developed an AgarTrap-mediated transformation method using intact gemmae/gemmalings produced by asexual reproduction. Using AgarTrap with male and female gemmae/gemmalings produced a sufficient number of independent transgenic gemmalings with uniform genetic backgrounds. The optimized transformation efficiencies were approximately 30 and 50 % in males and females, respectively. As with AgarTrap using sporelings, AgarTrap using intact gemmae/gemmalings will be useful in promoting studies of the molecular biology of M. polymorpha. PMID:25663453

  10. Agar disk elution method for susceptibility testing of Mycobacterium marinum and Mycobacterium fortuitum complex to sulfonamides and antibiotics.

    PubMed Central

    Stone, M S; Wallace, R J; Swenson, J M; Thornsberry, C; Christensen, L A

    1983-01-01

    An agar disk elution method using round well plates, supplemented Mueller-Hinton agar, and commercial drug disks is described for susceptibility testing of Mycobacterium marinum and the rapidly growing mycobacteria to antibiotics and sulfonamides. By this method, 14 of 14 strains of M. marinum were susceptible to rifampin, doxycycline, minocycline, and trimethoprim-sulfamethoxazole. Identical results were obtained with Middlebrook 7H10 agar and drugs prepared from standard powders. With 58 isolates of Mycobacterium fortuitum and Mycobacterium chelonei, this method had a 92% correlation with broth minimal inhibitory concentration determinations for cefoxitin and greater than 98% for doxycycline, kanamycin, amikacin, and the sulfonamides. Sixty-nine percent of isolates of M. chelonei susceptible to amikacin on supplemented Mueller-Hinton agar were resistant on 7H10 agar, and 15 of 16 M. chelonei isolates susceptible to erythromycin in broth were resistant by disk elution when an endpoint of no growth was used with either agar. The agar disk elution method offers a practical method for testing of most antibacterial agents against these mycobacterial species. Images PMID:6651277

  11. Blue metal complex pigments involved in blue flower color.

    PubMed

    Takeda, Kosaku

    2006-05-01

    The blue pigment of cornflower, protocyanin, has been investigated for a long time, but its precise structure was not entirely explained until recently. The molecular structure of the pigment was recently shown to be a metal complex of six molecules each of anthocyanin and flavone glycoside, with one ferric iron, one magnesium and two calcium ions by X-ray crystallographic analysis. The studies provided the answer to the question posed in the early part of the last century, "why is the cornflower blue and rose red when both flowers contain the same anthocyanin?" This work was achieved on the basis of the results of long years of the studies made by many researchers. In this review, the author focuses on the investigations of the blue metal complex pigments involved in the bluing of flowers, commelinin from Commelina commusis, protocyanin from Centaurea cyanus, protodelphin from Salvia patens and hydrangea blue pigment. PMID:25792777

  12. Blue metal complex pigments involved in blue flower color

    PubMed Central

    Takeda, Kosaku

    2006-01-01

    The blue pigment of cornflower, protocyanin, has been investigated for a long time, but its precise structure was not entirely explained until recently. The molecular structure of the pigment was recently shown to be a metal complex of six molecules each of anthocyanin and flavone glycoside, with one ferric iron, one magnesium and two calcium ions by X-ray crystallographic analysis. The studies provided the answer to the question posed in the early part of the last century, why is the cornflower blue and rose red when both flowers contain the same anthocyanin? This work was achieved on the basis of the results of long years of the studies made by many researchers. In this review, the author focuses on the investigations of the blue metal complex pigments involved in the bluing of flowers, commelinin from Commelina commusis, protocyanin from Centaurea cyanus, protodelphin from Salvia patens and hydrangea blue pigment. PMID:25792777

  13. Growth of Yersinia pseudotuberculosis and Yersinia enterocolitica biotype 3B serotype O3 inhibited on cefsulodin-Irgasan-novobiocin agar.

    PubMed Central

    Fukushima, H; Gomyoda, M

    1986-01-01

    A total of 169 strains of Yersinia spp. were analyzed for their ability to grow on two different kinds of cefsulodin-Irgasan-novobiocin (CIN) agar containing 15 or 4 micrograms of cefsulodin per ml, on salmonella-shigella agar, and on MacConkey agar. CIN media inhibited the growth of Yersinia pseudotuberculosis and Yersinia enterocolitica biotype 3B serotype O3 (3B/O3) but not the growth of the other Yersinia organisms used. Relative to growth on Trypticase soy agar (BBL Microbiology Systems, Cockeysville, Md.) with 6% yeast extract, 48 and 44% of Y. pseudotuberculosis and Y. enterocolitica 3B/O3 strains, respectively, were inhibited on CIN I agar (low cefsulodin concentration), and 83 and 54%, respectively, were inhibited on CIN II agar (high cefsulodin concentration) after incubation for 24 h at 32 degrees C. The inhibition of Y. pseudotuberculosis growth was significantly more extensive on CIN II agar than on CIN I agar. The MICs of cefsulodin and novobiocin clearly indicated a higher susceptibility for Y. pseudotuberculosis than for the other Yersinia organisms at 32 degrees C. All Y. pseudotuberculosis strains were susceptible to cefsulodin at 15 micrograms/ml (the approximate concentration used in CIN II agar). Y. enterocolitica 3B/O3 strains were resistant to cefsulodin, Irgasan, and novobiocin at the concentrations used in CIN media. These findings show that cefsulodin inhibits the growth of Y. pseudotuberculosis at the concentration used in CIN media and that growth inhibition of Y. enterocolitica 3B/O3 is related to a component of the CIN Base. PMID:3722357

  14. Hazards of solar blue light

    SciTech Connect

    Okuno, Tsutomu

    2008-06-01

    Short-wavelength visible light (blue light) of the Sun has caused retinal damage in people who have stared fixedly at the Sun without adequate protection. The author quantified the blue-light hazard of the Sun according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines by measuring the spectral radiance of the Sun. The results showed that the exposure limit for blue light can be easily exceeded when people view the Sun and that the solar blue-light hazard generally increases with solar elevation, which is in accordance with a model of the atmospheric extinction of sunlight. Viewing the Sun can be very hazardous and therefore should be avoided except at very low solar elevations.

  15. Hazards of solar blue light.

    PubMed

    Okuno, Tsutomu

    2008-06-01

    Short-wavelength visible light (blue light) of the Sun has caused retinal damage in people who have stared fixedly at the Sun without adequate protection. The author quantified the blue-light hazard of the Sun according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines by measuring the spectral radiance of the Sun. The results showed that the exposure limit for blue light can be easily exceeded when people view the Sun and that the solar blue-light hazard generally increases with solar elevation, which is in accordance with a model of the atmospheric extinction of sunlight. Viewing the Sun can be very hazardous and therefore should be avoided except at very low solar elevations. PMID:18516116

  16. In vitro/in vivo evaluation of agar nanospheres for pulmonary delivery of bupropion HCl.

    PubMed

    Varshosaz, Jaleh; Minaiyan, Mohsen; Zaki, Mohammad Reza; Fathi, Milad; Jaleh, Hossein

    2016-07-01

    Bupropion HCl is an atypical antidepressant drug with rapid and high first-pass metabolism. Sustained release dosage form of this drug is suggested for reducing its side effects which are mainly seizures. The aim of the present study was to design pulmonary agar nanospheres of bupropion HCl with effective systemic absorption and extended release properties. Bupropion HCl was encapsulated in agar nanospheres by ionic gelation, and characterized for physical and release properties. Pharmacokinetic studies on nanospheres were performed on rats by intratracheal spraying of 5 mg/kg of drug in form of nanospheres compared to intravenous and pulmonary delivery of the same dose as simple solution of the drug. The optimized nanoparticles showed particle size of 320 ± 90 nm with polydispersity index of 0.85, the zeta potential of -29.6 mV, drug loading efficiency of 43.1 ± 0.28% and release efficiency of 66.7 ± 2%. The area under the serum concentration-time profile for the pulmonary nanospheres versus simple solution was 10 237.84 versus 28.8 µg/ml min, Tmax of 360 versus 60 min and the Cmax of 1927.93 versus9.93 ng/ml, respectively. The absolute bioavailability of the drug was 86.69% for nanospheres and 0.25% for pulmonary simple solution. Our results indicate that pulmonary delivery of bupropion loaded agar nanospheres achieves systemic exposure and extends serum levels of the drug. PMID:25835223

  17. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin

    NASA Astrophysics Data System (ADS)

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C.

    2015-03-01

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure—PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery.

  18. Cavitation-enhanced delivery of insulin in agar and porcine models of human skin.

    PubMed

    Feiszthuber, Helga; Bhatnagar, Sunali; Gyöngy, Miklós; Coussios, Constantin-C

    2015-03-21

    Ultrasound-assisted transdermal insulin delivery offers a less painful and less invasive alternative to subcutaneous insulin injections. However, ultrasound-based drug delivery, otherwise known as sonophoresis, is a highly variable phenomenon, in part dependent on cavitation. The aim of the current work is to investigate the role of cavitation in transdermal insulin delivery. Fluorescently stained, soluble Actrapid insulin was placed on the surface of human skin-mimicking materials subjected to 265 kHz, 10% duty cycle focused ultrasound. A confocally and coaxially aligned 5 MHz broadband ultrasound transducer was used to detect cavitation. Two different skin models were used. The first model, 3% agar hydrogel, was insonated with a range of pressures (0.25-1.40 MPa peak rarefactional focal pressure-PRFP), with and without cavitation nuclei embedded within the agar at a concentration of 0.05% w/v. The second, porcine skin was insonated at 1.00 and 1.40 MPa PRFP. In both models, fluorescence measurements were used to determine penetration depth and concentration of delivered insulin. Results show that in agar gel, both insulin penetration depth and concentration only increased significantly in the presence of inertial cavitation, with up to a 40% enhancement. In porcine skin the amount of fluorescent insulin was higher in the epidermis of those samples that were exposed to ultrasound compared to the control samples, but there was no significant increase in penetration distance. The results underline the importance of instigating and monitoring inertial cavitation during transdermal insulin delivery. PMID:25716689

  19. Coma in the course of severe poisoning after consumption of red fly agaric (Amanita muscaria).

    PubMed

    Mikaszewska-Sokolewicz, Małgorzata A; Pankowska, Sylwestra; Janiak, Marek; Pruszczyk, Piotr; Łazowski, Tomasz; Jankowski, Krzysztof

    2016-01-01

    Red fly agaric poisoning is rare. It can be consumed for suicidal purposes or its psychedelic effect. The paper describes the case of a young men, who fell into a coma after ingestion of the red toadstools. Quick identification of the poison, early use of gastric lavage and symptomatic treatment resulted in regression of symptoms and lead to the patient's discharge from the hospital on the third day after intoxication. Authors discussing the poisonous alkaloids contained in the red toadtools: ibotenic acid, muscimol, muscasone and muscarine and theirs properties, responsible for the symptoms of intoxication. PMID:26828668

  20. Amino acid mediated synthesis of silver nanoparticles and preparation of antimicrobial agar/silver nanoparticles composite films.

    PubMed

    Shankar, Shiv; Rhim, Jong-Whan

    2015-10-01

    Silver nanoparticles (AgNPs) were synthesized using amino acids (tyrosine and tryptophan) as reducing and capping agents, and they were incorporated into the agar to prepare antimicrobial composite films. The AgNPs solutions exhibited characteristic absorption peak at 420 nm that showed a red shift to ∼434 nm after forming composite with agar. XRD data demonstrated the crystalline structure of AgNPs with dominant (111) facet. Apparent surface color and transmittance of agar films were greatly influenced by the AgNPs. The incorporation of AgNPs into agar did not exhibit any change in chemical structure, thermal stability, moisture content, and water vapor permeability. The water contact angle, tensile strength, and modulus decreased slightly, but elongation at break increased after AgNPs incorporation. The agar/AgNPs nanocomposite films possessed strong antibacterial activity against Listeria monocytogenes and Escherichia coli. The agar/AgNPs film could be applied to the active food packaging by controlling the food-borne pathogens. PMID:26076636

  1. ABC chromogenic agar: a cost-effective alternative to standard enteric media for Salmonella spp. isolation from routine stool samples.

    PubMed

    O'Neill, W; Cooke, R P D; Plumb, H; Kennedy, P

    2003-01-01

    Salmonellosis is the second most common cause of bacterial gastroenteritis, yet the yield from routine stool culture is low. Commonly used selective enteric media have poor specificities for salmonella identification, resulting in a high laboratory workload. A special chromogenic medium, ABC agar, is a promising alternative but its cost-effectiveness has not been evaluated in diagnostic laboratories. A collaborative study is therefore undertaken in two district general hospitals laboratories. Routine stool samples (n=866) were subcultured onto ABC agar half plates after selective enrichment in selenite broth. Similarly, 246 and 620 stool samples were subcultured onto desoxycholate lactose sucrose (DCLS) and xylose lactose desoxycholate (XLD) whole agar plates, respectively. Salmonella spp. were isolated from only 14 (1.6%) of stool samples tested. Specificity was significantly higher for ABC (98%) than DCLS (67%) or XLD (78%) agars. Welcan workload units (ABC 4.8, XLD and DCLS both 7.3) and costs per specimen (ABC 1.26 pounds sterling, DCLS 3.81 pounds sterling and XLD 1.83 pounds sterling) were similarly lower with ABC agar. The results indicate that ABC chromogenic agar offers improvements in specificity, workload and costs over conventional enteric media for Salmonella spp. isolation. PMID:14725333

  2. Blue-noise multitone dithering.

    PubMed

    Bacca Rodriguez, J; Arce, G R; Lau, D L

    2008-08-01

    The introduction of the blue-noise spectra-high-frequency white noise with minimal energy at low frequencies-has had a profound impact on digital halftoning for binary display devices, such as inkjet printers, because it represents an optimal distribution of black and white pixels producing the illusion of a given shade of gray. The blue-noise model, however, does not directly translate to printing with multiple ink intensities. New multilevel printing and display technologies require the development of corresponding quantization algorithms for continuous tone images, namely multitoning. In order to define an optimal distribution of multitone pixels, this paper develops the theory and design of multitone, blue-noise dithering. Here, arbitrary multitone dot patterns are modeled as a layered superposition of stack-constrained binary patterns. Multitone blue-noise exhibits minimum energy at low frequencies and a staircase-like, ascending, spectral pattern at higher frequencies. The optimum spectral profile is described by a set of principal frequencies and amplitudes whose calculation requires the definition of a spectral coherence structure governing the interaction between patterns of dots of different intensities. Efficient algorithms for the generation of multitone, blue-noise dither patterns are also introduced. PMID:18632346

  3. Mechanical and water barrier properties of agar/κ-carrageenan/konjac glucomannan ternary blend biohydrogel films.

    PubMed

    Rhim, Jong-Whan; Wang, Long-Feng

    2013-07-01

    Multicomponent hydrogel films composed of agar, κ-carrageenan, konjac glucomannan powder, and nanoclay (Cloisite(®) 30B) were prepared and their mechanical and water barrier properties such as water vapor permeability (WVP), water contact angle (CA), water solubility (WS), water uptake ratio (WUR), water vapor uptake ratio (WVUR) were determined. Mechanical, water vapor barrier, and water resistance properties of the ternary blend film exhibited middle range of individual component films, however, they increased significantly after formation of nanocomposite with the clay. Especially, the water holding capacity of the ternary blend biopolymer films increased tremendously, from 800% to 1681% of WUR for agar and κ-carrageenan films up to 5118% and 5488% of WUR for the ternary blend and ternary blend nanocomposite films, respectively. Water vapor adsorption behavior of films was also tested by water vapor adsorption kinetics and water vapor adsorption isotherms test. Preliminary test result for fresh spinach packaging revealed that the ternary blend biohydrogel films had a high potential for the use as an antifogging film for packaging highly respiring agricultural produce. In addition, the ternary blend nanocomposite film showed an antimicrobial activity against Gram-positive bacteria, Listeria monocytogenes. PMID:23688456

  4. Evaluation of a Modified Cefsulodin-Irgasan-Novobiocin Agar for Isolation of Yersinia spp

    PubMed Central

    Tan, Lai Kuan; Ooi, Peck Toung; Carniel, Elisabeth; Thong, Kwai Lin

    2014-01-01

    Y. enterocolitica and Y. pseudotuberculosis are important food borne pathogens. However, the presence of competitive microbiota makes the isolation of Y. enterocolitica and Y. pseudotuberculosis from naturally contaminated foods difficult. We attempted to evaluate the performance of a modified Cefsulodin-Irgasan-Novobiocin (CIN) agar in the differentiation of Y. enterocolitica from non-Yersinia species, particularly the natural intestinal microbiota. The modified CIN enabled the growth of Y. enterocolitica colonies with the same efficiency as CIN and Luria-Bertani agar. The detection limits of the modified CIN for Y. enterocolitica in culture medium (10 cfu/ml) and in artificially contaminated pork (104 cfu/ml) were also comparable to those of CIN. However, the modified CIN provided a better discrimination of Yersinia colonies from other bacteria exhibiting Yersinia-like colonies on CIN (H2S-producing Citrobacter freundii, C. braakii, Enterobacter cloacae, Aeromonas hydrophila, Providencia rettgeri, and Morganella morganii). The modified CIN exhibited a higher recovery rate of Y. enterocolitica from artificially prepared bacterial cultures and naturally contaminated samples compared with CIN. Our results thus demonstrated that the use of modified CIN may be a valuable means to increase the recovery rate of food borne Yersinia from natural samples, which are usually contaminated by multiple types of bacteria. PMID:25170941

  5. Abolition of Swarming of Proteus by p-Nitrophenyl Glycerin: Application to Blood Agar Media

    PubMed Central

    Williams, Fred D.

    1973-01-01

    Comparative plate counts were made of Staphylococcus aureus and Streptococcus pyogenes growing on blood agar supplemented with individual chemicals to abolish the swarming of Proteus. B-phenylethanol, sodium azide, and p-nitrophenyl glycerin (PNPG) were used as anti-swarm agents. Each anti-swarm agent effectively abolished swarming for 24 h, but azide failed to control swarming for longer periods of incubation. In addition, azide displayed growth inhibition towards the staphylococci and streptococci resulting in no hemolysis and reduced viable cell numbers with the streptococci. Phenylethanol showed reduced viable cell numbers with the streptococci and unreliable hemolytic reactions. At 0.1 to 0.3 mM, PNPG proved to be a superior anti-swarm agent in that it showed no growth inhibition and allowed normal hemolysis, but abolished swarming for extended periods of time. When laboratory strains of Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa. Listeria monocytogenes, and Vibrio cholerae were screened on a blood agar medium containing 0.1 mm PNPG, they displayed similar growth and hemolytic characteristics to the identical medium without PNPG. PMID:4715553

  6. Cinemicrographic Study of the Development of Subsurface Colonies of Staphylococcus aureus in Soft Agar

    PubMed Central

    Wilkins, Judd R.; Darnell, Wayne L.; Boykin, Elizabeth H.

    1972-01-01

    Cinemicrographic studies revealed that the development of elongated subsurface colonies of Staphylococcus aureus in soft agar (<0.2% agar) originated with a colony-forming unit of about 10 to 20 cells. It was then observed that small clusters of 3 to 12 cells broke off from the main colony unit and drifted away under the combined influence of gravity and Brownian motion. Once the downward or slightly sideward motion of the small clusters ceased, the clusters would continue to increase in size; at the same time, additional small clusters broke off, and the cycle was repeated until the entire colony was formed. Displacement and velocity measurements were made on the drifting small clusters. When compared with the dimensional growth rate and geometry of the subsurface colony, these showed that a correlation existed between the movement and velocity of the small clusters and the subsequent colony development. A relationship between the role of gravity reported in these results and the development of spherical colonies after rotation on a clinostat is suggested. Images PMID:4565637

  7. In vitro biocompatibility study of keratin/agar scaffold for tissue engineering.

    PubMed

    Nayak, Kush Kumar; Gupta, Pratima

    2015-11-01

    The porous scaffold was fabricated from a binary blend of keratin/agar for tissue engineering. The miscibility of keratin and agar polymers into their blend was confirmed by Fourier transform infrared spectroscopy and X-ray diffractometer study. The scaffold fabricated from freeze extraction method resulted in a porous interconnected structure with apparent porosity 94.40±2.34%. Scanning electron microscopy study reveals the presence of interconnected pores with a pore size ranges from 50 to 300μm. The hydrophilic nature of the scaffold was confirmed by water retention capacity studies, which was observed 160±7.89%. The scaffold's tensile strength of 0.154±0.031MPa and percent of elongation at break with 16.33±2.52% justify its mechanical capability. The positive antimicrobial property and in vitro degradation was recorded for the fabricated scaffold. The in vitro biocompatibility study of the scaffolds confirms the attachment and proliferation of the cultured mammalian myofibroblast cell line. Negative cytotoxicity and a viable cell growth ensure that the fabricated scaffold can serve a potential source of biomaterial for tissue engineering and can be applicable for wound healing and skin regeneration. PMID:26188296

  8. Mitis salivarius-bacitracin 10% sacarose agar for oral streptococci and Streptococcus mutans counts.

    PubMed

    Gutiérrez de Annan, S; Ruíz de Valladares, R E; Benito de Cárdenas, I L

    1997-01-01

    The MSB Agar (mitis salivarius-bacitracin) 20% sacarose medium is frequently used for the isolation and count of total streptococci and Streptococcus mutans. Although it is considered a selective culture medium for this micro-organism, S. mutans recovery in this medium is much lower than in this Mitis Salivarius Agar (MSA). Because the number of S. mutans in saliva is used for estimating caries risk and activity from a microbiological stand point, the aim of this work was to find a modification of the MSB 20% sacarose medium so that it would offer not only selectivity in the isolation but also maximum recovery. This would detect people at risk more efficiency and would evaluate the preventive odontological treatments more accurately. The results show that: 1) the greatest recovery of total streptococci and S. mutans is obtained in the MSB 10% sacarose medium, 2) S. mutans must be incubated in aerobiosis and the total streptococci in a candle jar (10% CO2). MSB 10% sacarose medium is proposed as a choice medium for the microbiological estimation of cariogenic risk and activity, to detect infection levels and evaluate preventive odontological treatments. PMID:11885081

  9. Visualization of Biosurfactant Film Flow in a Bacillus subtilis Swarm Colony on an Agar Plate

    PubMed Central

    Kim, Kyunghoon; Kim, Jung Kyung

    2015-01-01

    Collective bacterial dynamics plays a crucial role in colony development. Although many research groups have studied the behavior of fluidic swarm colonies, the detailed mechanics of its motion remains elusive. Here, we developed a visualization method using submicron fluorescent beads for investigating the flow field in a thin layer of fluid that covers a Bacillus subtilis swarm colony growing on an agar plate. The beads were initially embedded in the agar plate and subsequently distributed spontaneously at the upper surface of the expanding colony. We conducted long-term live cell imaging of the B. subtilis colony using the fluorescent tracers, and obtained high-resolution velocity maps of microscale vortices in the swarm colony using particle image velocimetry. A distinct periodic fluctuation in the average speed and vorticity of flow in swarm colony was observed at the inner region of the colony, and correlated with the switch between bacterial swarming and growth phases. At the advancing edge of the colony, both the magnitudes of velocity and vorticity of flow in swarm colony were inversely correlated with the spreading speed of the swarm edge. The advanced imaging tool developed in this study would facilitate further understanding of the effect of micro vortices in swarm colony on the collective dynamics of bacteria. PMID:26343634

  10. Evaluation of a modified Cefsulodin-Irgasan-Novobiocin agar for isolation of Yersinia spp.

    PubMed

    Tan, Lai Kuan; Ooi, Peck Toung; Carniel, Elisabeth; Thong, Kwai Lin

    2014-01-01

    Y. enterocolitica and Y. pseudotuberculosis are important food borne pathogens. However, the presence of competitive microbiota makes the isolation of Y. enterocolitica and Y. pseudotuberculosis from naturally contaminated foods difficult. We attempted to evaluate the performance of a modified Cefsulodin-Irgasan-Novobiocin (CIN) agar in the differentiation of Y. enterocolitica from non-Yersinia species, particularly the natural intestinal microbiota. The modified CIN enabled the growth of Y. enterocolitica colonies with the same efficiency as CIN and Luria-Bertani agar. The detection limits of the modified CIN for Y. enterocolitica in culture medium (10 cfu/ml) and in artificially contaminated pork (10(4) cfu/ml) were also comparable to those of CIN. However, the modified CIN provided a better discrimination of Yersinia colonies from other bacteria exhibiting Yersinia-like colonies on CIN (H2S-producing Citrobacter freundii, C. braakii, Enterobacter cloacae, Aeromonas hydrophila, Providencia rettgeri, and Morganella morganii). The modified CIN exhibited a higher recovery rate of Y. enterocolitica from artificially prepared bacterial cultures and naturally contaminated samples compared with CIN. Our results thus demonstrated that the use of modified CIN may be a valuable means to increase the recovery rate of food borne Yersinia from natural samples, which are usually contaminated by multiple types of bacteria. PMID:25170941

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

    PubMed

    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 < or = 0.001) according to the various media and time of incubation. Best results were obtained in 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. PMID:17390846

  12. Colonic cell growth and mucin degradation in rats fed diets containing various levels of beta-carotene with and without dietary agar.

    PubMed

    Hwa, S H; Shiau, S Y

    1993-06-01

    1. To either an agar-containing diet or an agar-free diet, 0, 0.3 and 2.0 mg/100 g of beta-carotene were incorporated and fed to groups of five rats for 28 days. 2. Weight gain and food consumption of rats fed different dietary groups did not show a significant difference (P > 0.05). 3. Colon weight, colonic mucosal DNA and RNA were generally higher in rats fed agar diets than rats fed agar-free diets at either beta-carotene supplementation level. 4. Mucinase activity was higher (P < 0.05) in rats fed the agar diet than in rats fed an agar-free diet without beta-carotene. However, the difference was not observed (P > 0.05) when beta-carotene was incorporated. 5. These data suggest that colonic mucin degradation in rats fed an agar diet decreased when the dietary beta-carotene inclusion level increased. PMID:7687211

  13. Evaluation of the Granada agar plate for detection of vaginal and rectal group B streptococci in pregnant women.

    PubMed

    Gil, E G; Rodríguez, M C; Bartolomé, R; Berjano, B; Cabero, L; Andreu, A

    1999-08-01

    Granada medium was evaluated for the detection of group B streptococci (GBS) in vaginal and rectal swabs compared with selective Columbia blood agar and selective Lim broth. From May 1996 to March 1998, 702 pregnant women (35 to 37 weeks of gestation) participated in this three-phase study; 103 (14.7%) of these women carried GBS. In the first phase of the experiment (n = 273 women), vaginorectal specimens were collected on the same swab; the sensitivities of Granada tube, selective Columbia blood agar, and Lim broth were 31.4, 94.3, and 74.3%, respectively. In the second and third phases (n = 429 women), vaginal and rectal specimens were collected separately; the sensitivities of Granada plate, selective Columbia blood agar, and Lim broth (subcultured at 4 h on selective Columbia agar in the second phase and at 18 to 24 h in Granada plate in the third phase) were 91.1, 83.9, and 75%, respectively, in the second phase and 88.5, 90.4, and 63.5%, respectively, in the third phase. There were no statistically significant differences in GBS recovery between the Granada agar plate and selective Columbia blood agar, but the Granada plate provided a clear advantage; the characteristic red-orange colonies produced overnight by GBS can be identified by the naked eye and is so specific that further identification is unnecessary. The use of the Granada tube and Lim broth did not result in increased isolation of GBS. In conclusion, the Granada agar plate is highly sensitive for detecting GBS in vaginal and rectal swabs from pregnant women and can provide results in 18 to 24 h. PMID:10405415

  14. Evaluation of the Granada Agar Plate for Detection of Vaginal and Rectal Group B Streptococci in Pregnant Women

    PubMed Central

    Gil, E. García; Rodríguez, M. C.; Bartolomé, R.; Berjano, B.; Cabero, L.; Andreu, A.

    1999-01-01

    Granada medium was evaluated for the detection of group B streptococci (GBS) in vaginal and rectal swabs compared with selective Columbia blood agar and selective Lim broth. From May 1996 to March 1998, 702 pregnant women (35 to 37 weeks of gestation) participated in this three-phase study; 103 (14.7%) of these women carried GBS. In the first phase of the experiment (n = 273 women), vaginorectal specimens were collected on the same swab; the sensitivities of Granada tube, selective Columbia blood agar, and Lim broth were 31.4, 94.3, and 74.3%, respectively. In the second and third phases (n = 429 women), vaginal and rectal specimens were collected separately; the sensitivities of Granada plate, selective Columbia blood agar, and Lim broth (subcultured at 4 h on selective Columbia agar in the second phase and at 18 to 24 h in Granada plate in the third phase) were 91.1, 83.9, and 75%, respectively, in the second phase and 88.5, 90.4, and 63.5%, respectively, in the third phase. There were no statistically significant differences in GBS recovery between the Granada agar plate and selective Columbia blood agar, but the Granada plate provided a clear advantage; the characteristic red-orange colonies produced overnight by GBS can be identified by the naked eye and is so specific that further identification is unnecessary. The use of the Granada tube and Lim broth did not result in increased isolation of GBS. In conclusion, the Granada agar plate is highly sensitive for detecting GBS in vaginal and rectal swabs from pregnant women and can provide results in 18 to 24 h. PMID:10405415

  15. Blue light emitting thiogallate phosphor

    DOEpatents

    Dye, Robert C.; Smith, David C.; King, Christopher N.; Tuenge, Richard T.

    1998-01-01

    A crystalline blue emitting thiogallate phosphor of the formula RGa.sub.2 S.sub.4 :Ce.sub.x where R is selected from the group consisting of calcium, strontium, barium and zinc, and x is from about 1 to 10 atomic percent, the phosphor characterized as having a crystalline microstructure on the size order of from about 100 .ANG. to about 10,000 .ANG. is provided together with a process of preparing a crystalline blue emitting thiogallate phosphor by depositing on a substrate by CVD and resultant thin film electroluminescent devices including a layer of such deposited phosphor on an ordinary glass substrate.

  16. The Blue-Collar Brain

    PubMed Central

    Van Orden, Guy; Hollis, Geoff; Wallot, Sebastian

    2012-01-01

    Much effort has gone into elucidating control of the body by the brain, less so the role of the body in controlling the brain. This essay develops the idea that the brain does a great deal of work in the service of behavior that is controlled by the body, a blue-collar role compared to the white-collar control exercised by the body. The argument that supports a blue-collar role for the brain is also consistent with recent discoveries clarifying the white-collar role of synergies across the body’s tensegrity structure, and the evidence of critical phenomena in brain and behavior. PMID:22719730

  17. Blue-green upconversion laser

    DOEpatents

    Nguyen, Dinh C.; Faulkner, George E.

    1990-01-01

    A blue-green laser (450-550 nm) uses a host crystal doped with Tm.sup.3+. The Tm.sup.+ is excited through upconversion by a red pumping laser and an IR pumping laser to a state which transitions to a relatively lower energy level through emissions in the blue-green band, e.g., 450.20 nm at 75 K. The exciting laser may be tunable dye lasers or may be solid-state semiconductor laser, e.g., GaAlAs and InGaAlP.

  18. Blue-green upconversion laser

    DOEpatents

    Nguyen, D.C.; Faulkner, G.E.

    1990-08-14

    A blue-green laser (450--550 nm) uses a host crystal doped with Tm[sup 3+]. The Tm[sup 3+] is excited through upconversion by a red pumping laser and an IR pumping laser to a state which transitions to a relatively lower energy level through emissions in the blue-green band, e.g., 450.20 nm at 75 K. The exciting laser may be tunable dye lasers or may be solid-state semiconductor laser, e.g., GaAlAs and InGaAlP. 3 figs.

  19. Colonyzer: automated quantification of micro-organism growth characteristics on solid agar

    PubMed Central

    2010-01-01

    Background High-throughput screens comparing growth rates of arrays of distinct micro-organism cultures on solid agar are useful, rapid methods of quantifying genetic interactions. Growth rate is an informative phenotype which can be estimated by measuring cell densities at one or more times after inoculation. Precise estimates can be made by inoculating cultures onto agar and capturing cell density frequently by plate-scanning or photography, especially throughout the exponential growth phase, and summarising growth with a simple dynamic model (e.g. the logistic growth model). In order to parametrize such a model, a robust image analysis tool capable of capturing a wide range of cell densities from plate photographs is required. Results Colonyzer is a collection of image analysis algorithms for automatic quantification of the size, granularity, colour and location of micro-organism cultures grown on solid agar. Colonyzer is uniquely sensitive to extremely low cell densities photographed after dilute liquid culture inoculation (spotting) due to image segmentation using a mixed Gaussian model for plate-wide thresholding based on pixel intensity. Colonyzer is robust to slight experimental imperfections and corrects for lighting gradients which would otherwise introduce spatial bias to cell density estimates without the need for imaging dummy plates. Colonyzer is general enough to quantify cultures growing in any rectangular array format, either growing after pinning with a dense inoculum or growing with the irregular morphology characteristic of spotted cultures. Colonyzer was developed using the open source packages: Python, RPy and the Python Imaging Library and its source code and documentation are available on SourceForge under GNU General Public License. Colonyzer is adaptable to suit specific requirements: e.g. automatic detection of cultures at irregular locations on streaked plates for robotic picking, or decreasing analysis time by disabling components such as lighting correction or colour measures. Conclusion Colonyzer can automatically quantify culture growth from large batches of captured images of microbial cultures grown during genome-wide scans over the wide range of cell densities observable after highly dilute liquid spot inoculation, as well as after more concentrated pinning inoculation. Colonyzer is open-source, allowing users to assess it, adapt it to particular research requirements and to contribute to its development. PMID:20509870

  20. M-RTLV agar, a novel selective medium to distinguish Lactobacillus casei and Lactobacillus paracasei from Lactobacillus rhamnosus.

    PubMed

    Sakai, Takafumi; Oishi, Kenji; Asahara, Takashi; Takada, Toshihiko; Yuki, Norikatsu; Matsumoto, Kazumasa; Nomoto, Koji; Kushiro, Akira

    2010-05-15

    We developed a novel selective medium, modified-rhamnose-2,3,5-triphenyltetrazolium chloride-LBS-vancomycin agar (M-RTLV agar), that utilizes the fermentability of L-rhamnose to distinguish Lactobacillus casei and Lactobacillus paracasei from Lactobacillus rhamnosus. Whereas L. casei and L. paracasei formed red colonies on the M-RTLV agar, L. rhamnosus formed either pink-toned colonies or white colonies with a red spot. An intervention study was conducted to confirm the capability of M-RTLV agar to detect ingested L. casei when recovered from human feces. Subjects consumed one bottle daily of a fermented milk product (Yakult or Yakult Light, which contains L. casei strain Shirota; LcS) for 7 days. Diluents of the fecal samples were cultivated on M-RTLV agar. We were able to enumerate circular medium-sized red colonies, which were morphologically similar to L. casei/L. paracasei but clearly distinguishable from the remaining colonies owing to the color difference. These colonies were then subjected to enzyme-linked immunosorbent assay in order to identify the LcS. The viable counts of LcS were 6.6+/-0.7 log(10) CFU/g feces after intake of Yakult and 6.5+/-0.6 log(10) CFU/g feces after intake of Yakult Light (mean+/-SD). PMID:20385416

  1. Infrared thermography analysis of thermal diffusion induced by RF magnetic field on agar phantoms loaded with magnetic nanoparticles

    NASA Astrophysics Data System (ADS)

    Bante-Guerra, Jose; Macías, J. D.; Caballero-Aguilar, L.; Vales-Pinzón, C.; Alvarado-Gil, J. J.

    2013-02-01

    Recently, several treatments for fighting malignant tumors have been designed. However these procedures have well known inconveniences, depending on their applicability, tumor size and side effects, among others. Magnetic hyperthermia is a safe, non-invasive method for cancer therapy. This treatment is applied via elevation of target tissue temperature by dissipation of heat from Magnetic Nanoparticles (MNPs), previously located within the tumor. The induction of heat causes cell death and therefore the removal of the tumor. In this work the thermal diffusion in phantoms of agar loaded with magnetic nanoparticles (MNPs) is studied using the infrared thermography technique, which is widely used in biology/medicine (e.g. skin temperature mapping). Agar is one of the materials used to simulate different types of body tissues, these samples are known as "phantoms". Agar is of natural origin, low cost and high degree of biocompatibility. In this work the agar gel was embedded with MNPs by coprecipitation and placed in an alternating magnetic field radiation. As a consequence, the energy from the radiation source is dissipated as heat and then transferred from the MNP to the gel, increasing its temperature. For the temperature analysis, the samples of agar gel were stimulated by RF magnetic field generated by coils. Heating was measured with infrared thermography using a Thermovision A20M infrared camera. Thermographic images allowed obtaining the dependence of thermal diffusion in the phantom as a function of the magnitude of the applied RF magnetic field and the load of magnetic particles.

  2. Nobel Prize for blue LEDs

    NASA Astrophysics Data System (ADS)

    Kraftmakher, Yaakov

    2015-05-01

    A brief review of lighting technologies is presented. Unavoidable restrictions for incandescent light bulbs caused by the Planck distribution and properties of the human eye are illustrated. The efficiency and luminous efficacy of thermal radiation are calculated for various temperatures; the results clearly show the limitations for thermal radiators. The only way to overcome these limitations is using non-thermal radiators, such as fluorescent lamps and light-emitting diodes (LEDs). Unique advantages of LEDs undoubtedly made a revolution in this field. A crucial element of this progress is the blue LEDs (Nobel Prize 2014). Some experiments with a blue and a green LED are described: (i) the luminescence triggered in a green-yellow phosphor inside a white LED by the blue LED; (ii) radiant spectra and ‘efficiency droop’ in the LEDs; (iii) modulation of the blue LED up to 4 MHz; and (iv) the h/e ratio from the turn-on voltage of the green LED. The experiments are suitable for undergraduate laboratories and usable as classroom demonstrations.

  3. Singing' the Black and Blues

    ERIC Educational Resources Information Center

    Fisher, Diane

    2004-01-01

    It is so obvious that the sky is blue in the daytime and black at night, but it took the smartest humans thousands of years of observation, thought, discussion, conjecture, and analysis to finally come up with answers that make scientific sense as to why the sky is these colors. This article discusses light and the scientific research

  4. Singing' the Black and Blues

    ERIC Educational Resources Information Center

    Fisher, Diane

    2004-01-01

    It is so obvious that the sky is blue in the daytime and black at night, but it took the smartest humans thousands of years of observation, thought, discussion, conjecture, and analysis to finally come up with answers that make scientific sense as to why the sky is these colors. This article discusses light and the scientific research…

  5. Optically Modulatable Blue Fluorescent Proteins

    PubMed Central

    Jablonski, Amy E.; Vegh, Russell B.; Hsiang, Jung-Cheng; Bommarius, Bettina; Chen, Yen-Cheng; Solntsev, Kyril M.; Bommarius, Andreas S.; Tolbert, Laren M.; Dickson, Robert M.

    2014-01-01

    Blue fluorescent proteins (BFPs) offer visualization of protein location and behavior, but often suffer from high autofluorescent background and poor signal discrimination. Through dual-laser excitation of bright and photoinduced dark states, mutations to the residues surrounding the BFP chromophore enable long-wavelength optical modulation of BFP emission. Such dark state engineering enables violet-excited blue emission to be increased upon lower energy, green co-illumination. Turning this green co-illumination on and off at a specific frequency dynamically modulates collected blue fluorescence without generating additional background. Interpreted as transient photoconversion between neutral cis- and anionic trans- chromophoric forms, mutations tune photoisomerization and ground state tautomerizations to enable long-wavelength depopulation of the millisecond-lived, spectrally shifted dark states. Single mutations to the tyrosine-based blue fluorescent protein T203V/S205V exhibit enhanced modulation depth and varied frequency. Importantly, analogous single point mutations in the non-modulatable BFP, mKalama1, creates a modulatable variant. Building modulatable BFPs offers opportunities for improved BFP signal discrimination vs. background, greatly enhancing their utility. PMID:24099419

  6. Nutrient Requirements of Renibacterium salmoninarum on Agar and in Broth Media.

    PubMed

    Daly, J G; Stevenson, R M

    1993-07-01

    In well-aerated broth cultures, good growth of Renibacterium salmoninarum was obtained in a serum-free medium consisting of 1% peptone, 1% yeast extract, and 0.1% l-cysteine (PYC broth). In contrast, serum or charcoal is required for growth on agar medium. Charcoal treatment of broth media, either before bacterial inoculation or during growth, increased the growth of R. salmoninarum, whereas the surfactants Tween 20 and Tween 80 inhibited growth. l-Cysteine was essential for optimal growth. Other organic sulfur compounds, such as d-cysteine, l-methionine, homocysteine, homocysteine thiolactone, and reduced glutathione, supported only lower levels of growth, while cystine and dithiothreitol did not allow growth. PMID:16348993

  7. Nutrient Requirements of Renibacterium salmoninarum on Agar and in Broth Media

    PubMed Central

    Daly, J. G.; Stevenson, R. M. W.

    1993-01-01

    In well-aerated broth cultures, good growth of Renibacterium salmoninarum was obtained in a serum-free medium consisting of 1% peptone, 1% yeast extract, and 0.1% l-cysteine (PYC broth). In contrast, serum or charcoal is required for growth on agar medium. Charcoal treatment of broth media, either before bacterial inoculation or during growth, increased the growth of R. salmoninarum, whereas the surfactants Tween 20 and Tween 80 inhibited growth. l-Cysteine was essential for optimal growth. Other organic sulfur compounds, such as d-cysteine, l-methionine, homocysteine, homocysteine thiolactone, and reduced glutathione, supported only lower levels of growth, while cystine and dithiothreitol did not allow growth. PMID:16348993

  8. Charcoal agar, a new growth medium for the fish disease bacterium Renibacterium salmoninarum.

    PubMed Central

    Daly, J G; Stevenson, R M

    1985-01-01

    Charcoal is an effective replacement for serum in media for the isolation and culture of Renibacterium salmoninarum, the causative agent of bacterial kidney disease in salmonid fish. The medium, KDM-C, contains 10 g of peptone, 0.5 g of yeast extract, 1 g of L-cysteine hydrochloride, 1 g of activated charcoal, and 15 g of agar per liter and is adjusted to pH 6.8 with NaOH before autoclaving. Eight strains of R. salmoninarum grew from dilute inocula as well on KDM-C as on a standard serum-containing medium (KDM-2). The medium was effective for both primary isolations from fish and repeated transfers and has potential value for antigen preparation and physiological studies. Images PMID:4083882

  9. Growth of Bacillus cereus on solid media as affected by agar, sodium chloride, and potassium sorbate.

    PubMed

    Stecchini, M L; Del Torre, M; Donda, S; Maltini, E

    2000-07-01

    The effect of two independent variables: microstructure, as modified by the agar content (1.0, 4.0, 7.0%), and water activity (a(w)), as modified by the NaCl content (0.5, 2.5, 4.5%), in the absence or in the presence of potassium sorbate (0.0; 2,000 ppm) on Bacillus cereus growth on solid media was studied. The time to visible growth (TVG) and the radial growth rate (RGR) of colonies were evaluated. TVG was not affected by microstructure and K-sorbate, although when a(w) was reduced, TVG tended to increase. RGR depended on linear effects of microstructure and a(w) variables and their interaction. When K-sorbate was added to cultural media, RGR was reduced significantly. However, in the presence of K-sorbate, RGR was found to change only when a(w) vas varied. PMID:10914662

  10. Serotyping reanalysis of unserotypable Actinobacillus pleuropneumoniae isolates by agar gel diffusion test.

    PubMed

    Morioka, Ayako; Shimazaki, Yoko; Uchiyama, Mariko; Suzuki, Shoko

    2016-05-01

    We observed increasing unserotypable (UT) Actinobacillus pleuropneumoniae isolates using agar gel diffusion (AGD) test. To reanalyze their serovar, we performed rapid slide agglutination (RSA) test and multiplex PCR for 47 UT isolates. Of these, 25 were serovar 1 (UT-serovar 1), 20 were serovar 2 (UT-serovar 2) and 2 were serovar 15 (UT-serovar 15). We examined serotyping antigen extraction temperature to determine heat influence. UT-serovar 1 and 15 were influenced by heat, because their precipitation lines were observed in the case of low antigen extraction temperature. To investigate the relationship between antigenicity and genotype, we performed pulsed-field gel electrophoresis (PFGE) analysis using UT-serovar 2 and 15. The predominant PFGE pattern of UT-serovar 2 was identical to that of serovar 2. PMID:26726101

  11. Cell cytotoxicity and mycotoxin and secondary metabolite production by common penicillia on cheese agar.

    PubMed

    Larsen, Thomas Ostenfeld; Gareis, Manfred; Frisvad, Jens Christian

    2002-10-01

    Known or potential new fungal starter culture species such as Penicillium camemberti, P. roqueforti, P. nalgiovense, P. caseifulvum, and P. solitum have been cultivated on a cheese agar medium together with the common cheese contaminants P. commune, P. crustosum, P. discolor, P. atramentosum, and P. nordicum. Secondary metabolites were extracted and analyzed by HPLC-DAD and tested for cytotoxicity by using the MTT-cell culture assay. Metabolites such as cyclopiazonic acid, roquefortine C, and penitrem A, previously reported from cheese, were detected together with sclerotigenin, solistatin, meleagrin, oxaline, compactins, diaportins, chaetoglobosins, rugulovasines, verrucolones, anacines, verrucines, cyclopeptines, viridicatins, and viridic acid, all metabolites not previously reported from cheese. The two P. nalgiovense extracts were the most toxic in the MTT-cell culture test. These extracts contained diaportines together with a number of unknown compounds. P. roqueforti extracts were not toxic at all. Fungal extracts from the rest of the studied penicillia were toxic at levels between these two extremes. PMID:12358494

  12. Antimicrobial Disk Susceptibility Testing of Leptospira spp. Using Leptospira Vanaporn Wuthiekanun (LVW) Agar

    PubMed Central

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Langla, Sayan; White, Nicholas J.; Day, Nicholas P. J.; Limmathurotsakul, Direk; Peacock, Sharon J.

    2015-01-01

    Leptospira Vanaporn Wuthiekanun (LVW) agar was used to develop a disk diffusion assay for Leptospira spp. Ten pathogenic Leptospira isolates were tested, all of which were susceptible to 17 antimicrobial agents (amoxicillin/clavulanic acid, amoxicillin, azithromycin, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, doripenem, doxycycline, gentamicin, linezolid, nitrofurantoin, penicillin, piperacillin/tazobactam, and tetracycline). All 10 isolates had no zone of growth inhibition for four antimicrobials (fosfomycin, nalidixic acid, rifampicin, and trimethoprim/sulfamethoxazole). Of the ten Leptospira, seven had a growth inhibition zone of ≤ 21 mm for aztreonam, the zone diameter susceptibility break point for Enterobacteriaceae. This assay could find utility as a simple screening method during the epidemiological surveillance of antimicrobial resistance in Leptospira spp. PMID:26055750

  13. Antimicrobial Disk Susceptibility Testing of Leptospira spp. Using Leptospira Vanaporn Wuthiekanun (LVW) Agar.

    PubMed

    Wuthiekanun, Vanaporn; Amornchai, Premjit; Langla, Sayan; White, Nicholas J; Day, Nicholas P J; Limmathurotsakul, Direk; Peacock, Sharon J

    2015-08-01

    Leptospira Vanaporn Wuthiekanun (LVW) agar was used to develop a disk diffusion assay for Leptospira spp. Ten pathogenic Leptospira isolates were tested, all of which were susceptible to 17 antimicrobial agents (amoxicillin/clavulanic acid, amoxicillin, azithromycin, cefoxitin, ceftazidime, ceftriaxone, chloramphenicol, ciprofloxacin, clindamycin, doripenem, doxycycline, gentamicin, linezolid, nitrofurantoin, penicillin, piperacillin/tazobactam, and tetracycline). All 10 isolates had no zone of growth inhibition for four antimicrobials (fosfomycin, nalidixic acid, rifampicin, and trimethoprim/sulfamethoxazole). Of the ten Leptospira, seven had a growth inhibition zone of ≤ 21 mm for aztreonam, the zone diameter susceptibility break point for Enterobacteriaceae. This assay could find utility as a simple screening method during the epidemiological surveillance of antimicrobial resistance in Leptospira spp. PMID:26055750

  14. Bacterial culture detection and identification in blood agar plates with an optoelectronic nose.

    PubMed

    Lim, Sung H; Mix, Samantha; Anikst, Victoria; Budvytiene, Indre; Eiden, Michael; Churi, Yair; Queralto, Nuria; Berliner, Anders; Martino, Raymond A; Rhodes, Paul A; Banaei, Niaz

    2016-02-01

    Clinical microbiology automation is currently limited by the lack of an in-plate culture identification system. Using an inexpensive, printed, disposable colorimetric sensor array (CSA) responsive to the volatiles emitted into plate headspace by microorganisms during growth, we report here that not only the presence but the species of bacteria growing in plate was identified before colonies are visible. In 1894 trials, 15 pathogenic bacterial species cultured on blood agar were identified with 91.0% sensitivity and 99.4% specificity within 3 hours of detection. The results indicate CSAs integrated into Petri dish lids present a novel paradigm to speciate microorganisms, well-suited to integration into automated plate handling systems. PMID:26753182

  15. Stimulating growth and xylindein production of Chlorociboria aeruginascens in agar-based systems

    PubMed Central

    2012-01-01

    Four isolates of Chlorociboria aeruginascens were tested for possible stimulatory effects when grown on malt agar media containing wood additives. The addition of any of the four types of test wood (Acer saccharum, Populus tremuloides, spalted P. tremuloides, and Ailanthus altissima), stimulated colony growth and xylindein production in C. aeruginascens. Addition of any amount of wood produced more growth than no wood additions, while ground wood produced more growth than chopped wood. Of the wood types tested, A. saccharum wood stimulated all four isolates, while spalted Populus tremuloides stimulated three of the four isolates. High glucose and sucrose amounts may be partially responsible for the greater stimulatory affect of some woods over others. The development of this simple and reliable method for growth and pigment stimulation of C. aeruginascens in laboratory conditions will allow for further development of this fungus for decorative and commercial use. PMID:22409931

  16. Serotyping reanalysis of unserotypable Actinobacillus pleuropneumoniae isolates by agar gel diffusion test

    PubMed Central

    MORIOKA, Ayako; SHIMAZAKI, Yoko; UCHIYAMA, Mariko; SUZUKI, Shoko

    2016-01-01

    We observed increasing unserotypable (UT) Actinobacillus pleuropneumoniae isolates using agar gel diffusion (AGD) test. To reanalyze their serovar, we performed rapid slide agglutination (RSA) test and multiplex PCR for 47 UT isolates. Of these, 25 were serovar 1 (UT-serovar 1), 20 were serovar 2 (UT-serovar 2) and 2 were serovar 15 (UT-serovar 15). We examined serotyping antigen extraction temperature to determine heat influence. UT-serovar 1 and 15 were influenced by heat, because their precipitation lines were observed in the case of low antigen extraction temperature. To investigate the relationship between antigenicity and genotype, we performed pulsed-field gel electrophoresis (PFGE) analysis using UT-serovar 2 and 15. The predominant PFGE pattern of UT-serovar 2 was identical to that of serovar 2. PMID:26726101

  17. Evaluation of agar dilution and broth microdilution methods to determine the disinfectant susceptibility.

    PubMed

    Wu, Guoyan; Yang, Qianru; Long, Mei; Guo, Lijuan; Li, Bei; Meng, Yue; Zhang, Anyun; Wang, Hongning; Liu, Shuliang; Zou, Likou

    2015-11-01

    A variety of disinfectants have been widely used in veterinary hygiene, food industries and environments, which could induce the development of bacterial resistance to disinfectants. The methods used to investigate antimicrobial effects of disinfectant vary considerably among studies, making comparisons difficult. In this study, agar dilution and broth microdilution methods were used to compare the antimicrobial activities of four quaternary ammonium compounds (QACs) against foodborne and zoonotic pathogens. The potential relationship between the presence of QACs resistance genes and phenotypic resistance to QACs was also investigated. Our results indicated that the minimum inhibitory concentrations (MICs) determined by two methods might be different depended upon different QACs and bacteria applied. Regardless of the testing methods, Klebsiella pneumoniae was more tolerant among Gram-negative strains to four QACs, followed by Salmonella and Escherichia coli. The agreement between MICs obtained by the two methods was good, for benzalkonium chloride (78.15%), didecyldimethylammonium chloride (DDAC) (82.35%), cetylpyridinium chloride (CTPC) (97.48%) and cetyltrimethylammonium bromide (CTAB) (99.16%), respectively. Among all Gram-negative bacteria, 94.55% (n=52) of qacEΔ1-positive strains showed higher MICs (512 mg l(-1)) to CTAB. The qacEΔ1 gene was highly associated (P<0.05) with the high MICs of QACs (⩾512 mg l(-1)). In addition, DDAC remained as the most effective disinfectant against both Gram-positive and Gram-negative bacteria. This is the first study that compared the agar dilution and broth microdilution methods to assess the antimicrobial activity of QACs. The study demonstrated the need to standardize method that would be used in evaluating QACs antimicrobial properties in the future. PMID:25944532

  18. 21 CFR 73.50 - Ultramarine blue.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ultramarine blue is a blue pigment obtained by calcining a mixture of kaolin, sulfur, sodium carbonate, and... order to vary the shade. The pigment is a complex sodium aluminum sulfo-silicate having the...

  19. 21 CFR 73.50 - Ultramarine blue.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ultramarine blue is a blue pigment obtained by calcining a mixture of kaolin, sulfur, sodium carbonate, and... order to vary the shade. The pigment is a complex sodium aluminum sulfo-silicate having the...

  20. 21 CFR 73.50 - Ultramarine blue.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ultramarine blue is a blue pigment obtained by calcining a mixture of kaolin, sulfur, sodium carbonate, and... order to vary the shade. The pigment is a complex sodium aluminum sulfo-silicate having the...

  1. 21 CFR 73.50 - Ultramarine blue.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ultramarine blue is a blue pigment obtained by calcining a mixture of kaolin, sulfur, sodium carbonate, and... order to vary the shade. The pigment is a complex sodium aluminum sulfo-silicate having the...

  2. Establishment of MICs of moxalactam for control and reference anaerobic organisms in agar dilution and microdilution techniques.

    PubMed

    Sutter, V L; Emmerman, J; Randall, E; Zabransky, R J; Birk, R J

    1985-03-01

    The MICs of moxalactam were determined for eight National Committee for Clinical Laboratory Standards control and reference strains and for Fusobacterium nucleatum ATCC 10953 by agar and microdilution techniques. The recommended MIC for the control strain Bacteroides fragilis in both agar and microdilution tests is 0.5 micrograms/ml. Recommended MICs for Bacteroides thetaiotaomicron ATCC 29741 and Clostridium perfringens ATCC 13124 by agar dilution are 8 and 0.063 micrograms/ml, respectively. These two strains gave inconsistent results in microdilution tests. Variation in results with microdilution procedures was seen, which illustrates problems in reading endpoints and with modifications of media. Recommended MICs for the reference strains are presented. PMID:3888103

  3. Impaction onto a Glass Slide or Agar versus Impingement into a Liquid for the Collection and Recovery of Airborne Microorganisms

    PubMed Central

    Juozaitis, Arvydas; Willeke, Klaus; Grinshpun, Sergey A.; Donnelly, Jean

    1994-01-01

    To study impaction versus impingement for the collection and recovery of viable airborne microorganisms, three new bioaerosol samplers have been designed and built. They differ from each other by the medium onto which the bioaerosol particles are collected (glass, agar, and liquid) but have the same inlet and collection geometries and the same sampling flow rate. The bioaerosol concentrations recorded by three different collection techniques have been compared with each other: impaction onto a glass slide, impaction onto an agar medium, and impingement into a liquid. It was found that the particle collection efficiency of agar slide impaction depends on the concentration of agar in the collection medium and on the sampling time, when samples are collected on a nonmoving agar slide. Impingement into a liquid showed anomalous behavior with respect to the sampling flow rate. Optimal sampling conditions in which all three new samplers exhibit the same overall sampling efficiency for nonbiological particles have been established. Inlet and collection efficiencies of about 100% have been achieved for all three devices at a sampling flow rate of 10 liters/min. The new agar slide impactor and the new impinger were then used to study the biological factors affecting the overall sampling efficiency. Laboratory experiments on the total recovery of a typical environmental microorganism, Pseudomonas fluorescens ATCC 13525, showed that both sampling methods, impaction and impingement, provided essentially the same total recovery when relatively nonstressed microorganisms were sampled under optimal sampling conditions. Comparison tests of the newly developed bioaerosol samplers with those commercially available showed that the incorporation of our research findings into the design of the new samplers yields better performance data than data from currently available samplers. PMID:16349217

  4. Hair Sheep Blood, Citrated or Defibrinated, Fulfills All Requirements of Blood Agar for Diagnostic Microbiology Laboratory Tests

    PubMed Central

    Yeh, Ellen; Pinsky, Benjamin A.; Banaei, Niaz; Baron, Ellen Jo

    2009-01-01

    Background Blood agar is used for the identification and antibiotic susceptibility testing of many bacterial pathogens. In the developing world, microbiologists use human blood agar because of the high cost and inhospitable conditions for raising wool sheep or horses to supply blood. Many pathogens either fail to grow entirely or exhibit morphologies and hemolytic patterns on human blood agar that confound colony recognition. Furthermore, human blood can be hazardous to handle due to HIV and hepatitis [1], [2]. This study investigated whether blood from hair sheep, a hardy, low-maintenance variety of sheep adapted for hot climates, was suitable for routine clinical microbiology studies. Methods and Findings Hair sheep blood obtained by jugular venipuncture was anticoagulated by either manual defibrination or collection in human blood bank bags containing citrate-phosphate-dextrose. Trypticase soy 5% blood agar was made from both forms of hair sheep blood and commercial defibrinated wool sheep blood. Growth characteristics, colony morphologies, and hemolytic patterns of selected human pathogens, including several streptococcal species, were evaluated. Specialized identification tests, including CAMP test, reverse CAMP test, and satellite colony formation with Haemophilus influenzae and Abiotrophia defectiva were also performed. Mueller-Hinton blood agar plates prepared from the three blood types were compared in antibiotic susceptibility tests by disk diffusion and E-test. Conclusions The results of all studies showed that blood agar prepared from citrated hair sheep blood is suitable for microbiological tests used in routine identification and susceptibility profiling of human pathogens. The validation of citrated hair sheep blood eliminates the labor-intensive and equipment-requiring process of manual defibrination. Use of hair sheep blood, in lieu of human blood currently used by many developing world laboratories and as an alternative to cost-prohibitive commercial sheep blood, offers the opportunity to dramatically improve the safety and accuracy of laboratory diagnosis of pathogenic bacteria in resource-poor countries. PMID:19578541

  5. Appressorium-mediated penetration of Magnaporthe oryzae and Colletotrichum orbiculare into surface-cross-linked agar media.

    PubMed

    Tanaka, Eiji

    2015-05-01

    Many phytopathogenic fungi form appressoria on some artificial substances. However, it is difficult to induce appressorium-mediated penetration into artificial substances. In the present study, novel artificial agar media were developed to investigate the in vitro penetration process of phytopathogenic fungi. The media contained sodium carboxymethyl cellulose or sodium alginate, and the surfaces were subjected to ionic cross-linking using trivalent metal ions. The hemibiotrophic phytopathogenic fungi, rice blast fungus and cucurbit anthracnose fungus, formed appressoria and penetrated into the surface cross-linked artificial agar media from the base of appressoria. These artificial media appeared to induce fungal infection behaviour that occurred on host plants. PMID:25877547

  6. A new rhythm for the Blues.

    PubMed

    Tokarski, C

    1995-03-01

    If 1994 was the year the nation's Blue Cross and Blue Shield plans surpassed their managed care competitors in enrollment, 1995 is shaping up to be the year the Blues lead the stampede to form integrated delivery systems. Plus, a look at the new BC/BS chief, Patrick Hays. PMID:7866438

  7. 21 CFR 73.50 - Ultramarine blue.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Ultramarine blue. 73.50 Section 73.50 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... ultramarine blue is a blue pigment obtained by calcining a mixture of kaolin, sulfur, sodium carbonate,...

  8. On Seeing Reddish Green and Yellowish Blue.

    ERIC Educational Resources Information Center

    Crane, Hewitt D.; Piantanida, Thomas P.

    1983-01-01

    Stabilization of the retinal image of the boundary between a pair of red/green or yellow/blue stripes, but not their outer edges, results in the entire region being perceived simultaneously as both red/green or yellow/blue. This suggests that the percepts of reddish-green/yellowish-blue apparently are possible in corticocortical color vision…

  9. Status of Blue Ridge Reservoir

    SciTech Connect

    Not Available

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  10. The Physics of the Blues

    NASA Astrophysics Data System (ADS)

    Gibson, J. Murray

    2009-03-01

    In looking at the commonalities between music and science, one sees that the musician's palette is based on the principles of physics. The pitch of a musical note is determined by the frequency of the sound wave. The scales that musicians use to create and play music can be viewed as a set of rules. What makes music interesting is how musicians develop those rules and create ambiguity with them. I will discuss the evolution of western musical scales in this context. As a particular example, ``Blue'' notes are very harmonic notes that are missing from the equal temperament scale. The techniques of piano blues and jazz represent the melding of African and Western music into something totally new and exciting. Live keyboard demonstrations will be used. Beyond any redeeming entertainment value the talk will emphasize the serious connections between science and art in music. Nevertheless tips will be accepted.

  11. Ol' Blue Eyes, in Focus

    ERIC Educational Resources Information Center

    Nelson, Michael

    2009-01-01

    Scholarly books with "identity" and "culture" in the title have loomed large on academic publishing lists for several years. Scholarly books with "Sinatra" in the title are a more recent phenomenon. Despite his six-decade career as the Voice (the 1940s), the Chairman of the Board (the 50s and 60s), and Ol' Blue Eyes (the 70s through his death, in…

  12. Uncovering Blue Diffuse Dwarf Galaxies

    NASA Astrophysics Data System (ADS)

    James, Bethan; Koposov, Sergey; Stark, Daniel; Belokurov, Vasily; Pettini, Max; Olszewski, Edward W.

    2015-01-01

    Extremely metal-poor galaxies (XMPs) and the star-formation within their chemically pristine environments are fundamental to our understanding of the galaxy formation process at early times. However, traditional emission-line surveys detect only the brightest metal-poor galaxies where star-formation occurs in compact, starbursting environments, and thereby give us only a partial view of the dwarf galaxy population. To avoid such biases, we have developed a new search algorithm based on the morphological, rather then spectral, properties of XMPs and have applied to the Sloan Digital Sky Survey database of images. Using this novel approach, we have discovered ~100 previously undetected, faint blue galaxies, each with isolated HII regions embedded in a diffuse continuum. In this talk I will present the first results from follow-up optical spectroscopy of this sample, which reveals these blue diffuse dwarfs (BDDs) to be young, very metal-poor and actively forming stars despite their intrinsically low luminosities. I will present evidence showing that BDDs appear to bridge the gap between quiescent dwarf irregular (dIrr) galaxies and blue compact galaxies (BCDs) and as such offer an ideal opportunity to assess how star-formation occurs in more `normal' metal-poor systems.

  13. Models of Individual Blue Stragglers

    NASA Astrophysics Data System (ADS)

    Sills, Alison

    This chapter describes the current state of models of individual blue stragglers. Stellar collisions, binary mergers (or coalescence), and partial or ongoing mass transfer have all been studied in some detail. The products of stellar collisions retain memory of their parent stars and are not fully mixed. Very high initial rotation rates must be reduced by an unknown process to allow the stars to collapse to the main sequence. The more massive collision products have shorter lifetimes than normal stars of the same mass, while products between low mass stars are long-lived and look very much like normal stars of their mass. Mass transfer can result in a merger, or can produce another binary system with a blue straggler and the remnant of the original primary. The products of binary mass transfer cover a larger portion of the colour-magnitude diagram than collision products for two reasons: there are more possible configurations which produce blue stragglers, and there are differing contributions to the blended light of the system. The effects of rotation may be substantial in both collision and merger products, and could result in significant mixing unless angular momentum is lost shortly after the formation event. Surface abundances may provide ways to distinguish between the formation mechanisms, but care must be taken to model the various mixing mechanisms properly before drawing strong conclusions. Avenues for future work are outlined.

  14. The Cryptochrome Blue Light Receptors

    PubMed Central

    Yu, Xuhong; Liu, Hongtao; Klejnot, John; Lin, Chentao

    2010-01-01

    Cryptochromes are photolyase-like blue light receptors originally discovered in Arabidopsis but later found in other plants, microbes, and animals. Arabidopsis has two cryptochromes, CRY1 and CRY2, which mediate primarily blue light inhibition of hypocotyl elongation and photoperiodic control of floral initiation, respectively. In addition, cryptochromes also regulate over a dozen other light responses, including circadian rhythms, tropic growth, stomata opening, guard cell development, root development, bacterial and viral pathogen responses, abiotic stress responses, cell cycles, programmed cell death, apical dominance, fruit and ovule development, seed dormancy, and magnetoreception. Cryptochromes have two domains, the N-terminal PHR (Photolyase-Homologous Region) domain that bind the chromophore FAD (flavin adenine dinucleotide), and the CCE (CRY C-terminal Extension) domain that appears intrinsically unstructured but critical to the function and regulation of cryptochromes. Most cryptochromes accumulate in the nucleus, and they undergo blue light-dependent phosphorylation or ubiquitination. It is hypothesized that photons excite electrons of the flavin molecule, resulting in redox reaction or circular electron shuttle and conformational changes of the photoreceptors. The photoexcited cryptochrome are phosphorylated to adopt an open conformation, which interacts with signaling partner proteins to alter gene expression at both transcriptional and posttranslational levels and consequently the metabolic and developmental programs of plants. PMID:21841916

  15. Evaluation of a new agar medium containing cetrimide, kanamycin and nalidixic acid for isolation and enhancement of pigment production of Pseudomonas aeruginosa in clinical samples.

    PubMed

    Kodaka, Hidemasa; Iwata, Morihiro; Yumoto, Shigeo; Kashitani, Fusako

    2003-01-01

    A new selective agar medium (CKNA), containing cetrimide 0.3 g/l, kanamycin sulfate 50 mg/l, and nalidixic acid 5 mg/l, was developed for the isolation of Pseudomonas aeruginosa. It was compared to Nalidixic Acid Cetrimide agar (NAC), Pseudomonas Aeruginosa Selective Agar (PASA) and Pseudosel(TM) agar (CET) using 1,148 clinical specimens. The sensitivities rates of P. aeruginosa with CKNA, NAC, PASA, and CET were 88.2%, 81.3%, 79.2%, and 84.0%, respectively. The specificities of CKNA, NAC, PASA, and CET were 99.2%, 98.4%, 99.2%, and 99.7%, respectively. PMID:12964184

  16. Inflation and alternatives with blue tensor spectra

    SciTech Connect

    Wang, Yi; Xue, Wei E-mail: wei.xue@sissa.it

    2014-10-01

    We study the tilt of the primordial gravitational waves spectrum. A hint of blue tilt is shown from analyzing the BICEP2 and POLARBEAR data. Motivated by this, we explore the possibilities of blue tensor spectra from the very early universe cosmology models, including null energy condition violating inflation, inflation with general initial conditions, and string gas cosmology, etc. For the simplest G-inflation, blue tensor spectrum also implies blue scalar spectrum. In general, the inflation models with blue tensor spectra indicate large non-Gaussianities. On the other hand, string gas cosmology predicts blue tensor spectrum with highly Gaussian fluctuations. If further experiments do confirm the blue tensor spectrum, non-Gaussianity becomes a distinguishing test between inflation and alternatives.

  17. Controlled evaluation of the agar-slide and radiometric blood culture systems for the detection of bacteremia and fungemia.

    PubMed Central

    Weinstein, M P; Reller, L B; Mirrett, S; Stratton, C W; Reimer, L G; Wang, W L

    1986-01-01

    A commercially available agar-slide blood culture bottle (Septi-Chek; Roche Diagnostics, Div. Hoffman-La Roche, Inc., Nutley, N.J.) was compared with the radiometric blood culture system (BACTEC; Johnston Laboratories, Inc., Towson, Md.) in 8,544 paired blood cultures from adult patients. The systems were inoculated with equal volumes (10 ml) of blood. Overall, there was no statistically significant difference between the two systems in the recovery of clinically important microorganisms, but significantly more members of the family Enterobacteriaceae other than Escherichia coli were detected by the agar-slide system (P less than 0.005). The agar-slide system detected more fungi, and the BACTEC detected more anaerobic bacteria; however, small numbers of recovered organisms precluded statistical significance. When microorganisms grew in both systems, their presence was detected one or more days earlier in the BACTEC (P less than 0.001). More contaminants grew in the agar-slide system (P less than 0.001). Both systems performed well, and either system should provide high yield and prompt detection of positive blood cultures in patients with bacteremia and fungemia if used in an optimal way as recommended by the respective manufacturers. PMID:3517047

  18. Hydrogen-bond-mediated in situ fabrication of AgNPs/agar/PAN electrospun nanofibers as reproducible SERS substrates.

    PubMed

    Yang, Tong; Yang, Hui; Zhen, Shu Jun; Huang, Cheng Zhi

    2015-01-28

    Reproducibility in surface enhanced Raman scattering (SERS) measurements is a challenge. This work developed a facile way to make highly dispersed uniform silver nanoparticles (AgNPs) loaded in the agar/polyacrylonitrile (PAN) nanofibers by the coupling the electrospinning technology from metal complex-containing polymer solution and in situ photoreductive technique. Agar, as hydrophilic component, was introduced into the electrospinning solution considering that its abundant hydroxyl group sites could greatly improve the contents of silver ions in the polymers because of the rich silver ion chelated with the hydroxyl group, whereas hydrophilic agar was integrated with hydrophobic PAN by -OH···N≡C- hydrogen bonds as a bridge. Meanwhile, the in situ photoreductive reaction was made under different light irradiations such as desk lamp, 365 nm UV-lamp, and 254 nm UV-lamp. High yield of stable AgNPs with highly uniform and dispersion are available in the agar/PAN nanofibers after the in situ photoreductive reaction, supplying the possibility of reproducible SERS signals. To identify that concept of proof, a facile approach for the determination of malachite green (MG) in three environmental practical samples was demonstrated by using the composite nanofibrous material irradiated by 365 nm UV-lamp, giving the minimum detection concentration of MG as low as 0.1 μmol/L with a good linear response ranging from 0.1-100 μmol/L (R(2) = 0.9960). PMID:25546719

  19. [Clinical assessment of novel ChromID ESBL agar plates for detection of ESBL producers in the family Enterobacteriaceae].

    PubMed

    Kasuga, Eriko; Matsumoto, Takehisa; Hidaka, Eiko; Oguchi, Harumi; Kanai, Shinichiro; Oana, Kozue; Yamauchi, Kazuyoshi; Honda, Takayuki; Kawakami, Yoshiyuki

    2009-01-01

    Extended-Spectrum beta-Lactamase (ESBL)-producers in the family Enterobacteriaceae are recognized worldwide as nosocomial pathogens, however it is difficult to screen them in the routine laboratory processing. ChromID ESBL agar newly developed for screening ESBL-producing Enterobacteriaceae was released in Japan in April, 2007. We evaluated the clinical assessment of ChromID ESBL agar in routine microbiology laboratory. The 47 strains investigated were clinical isolates belonging to the family Enterobacteriaceae with the MICs of cefpodoxime greater than 2 mug/ml. The 27 ESBL-producers examined were comprising of 19 Escherichia coli, 3 Klebsiella oxytoca, 1 Citrobacter freundii, 3 Enterobacter cloacae, and 1 S. marcescens (ESBL group) and 20 ESBL non-producers consiating of 5 K. oxytoca, 1 Proteus mirabilis, 1 P. vlugaris, 2 Serratia marcescens, 8 C. freundii, 2 Enterobacter cloacae, and 1 E. aerogenes (non-ESBL group). Characterization of beta-lactamase genes was carried out by use of polymerase chain reaction. As the results, the sensitivity and the specificity of ChromID ESBL agar plates after incubation for 18 hours was 100% and 20%, respectively. It should be noted that the values of specificity was extremely low compared with those of the sensitivity. These findings clearly suggested that in cases of utilizing ChromID ESBL agar plates, it should be important to consider its characteristic properties, as even the ESBL-non-producers could grow on these media only when they were resistant to CPDX. PMID:20528091

  20. False susceptibility of enterococci to aminoglycosides with blood-enriched Mueller-Hinton agar for disk susceptibility testing.

    PubMed

    Jenkins, R D; Stevens, S L; Craythorn, J M; Thomas, T W; Guinan, M E; Matsen, J M

    1985-09-01

    Disk diffusion susceptibility tests for enterococci are frequently modified by adding 5% sheep blood (SB) to Mueller-Hinton agar; the performance standards from the National Committee for Clinical Laboratory Standards sanction this addition. Susceptibility testing of aminoglycoside antibiotics is not recommended for enterococci; in actual practice, however, some laboratories do include aminoglycoside antibiotics routinely, and others may test upon request or in selected situations. In examining 50 clinical isolates of enterococci, SB-enriched Mueller-Hinton agar frequently gave enlarged zone sizes that falsely indicated susceptibility (72% for gentamicin and tobramycin), with the average increase in zone size being 6.3 and 7.6 mm, respectively. Comparison agar dilution MICs demonstrated uniform resistance, with or without added SB. The effect was shown to be caused by heme in concentrations as low as 0.03 micrograms/ml, which, when combined with aminoglycoside antibiotics, caused a synergistic growth inhibition of the enterococci, resulting in larger aminoglycoside antibiotic zones. We postulate that the heme effect is related to a catalytic cleavage of intracellular H2O2 and resultant lipid peroxidation. No other organism or antimicrobial agent tested demonstrated a similar effect, although other investigators have shown a similar phenomenon with the broad-spectrum cephalosporins. Because enterococci grow well and give accurate susceptibility results on Mueller-Hinton agar without SB supplementation and because of the spectrum of definable problems with a number of antimicrobial agents, we recommend that enterococci routinely be tested without SB. PMID:4044795

  1. Multi-chamber electroosmosis using textile reinforced agar membranes--A promising concept for the future of hemodialysis.

    PubMed

    Kofler, Markus; Lenninger, Margit; Mayer, Gert; Neuwirt, Hannes; Grimm, Michael; Bechtold, Thomas

    2016-01-20

    Renal replacement therapy options are limited to hemodialysis and peritoneal dialysis (70% of US patients) or renal transplantation. Diffusion processes are the main physico-chemical principle behind hemodialysis. An alternative way to achieve liquid flow through membranes bases on the electroosmotic flow which is observed as electrokinetic phenomenon in porous membranes which bear surface charges. Agar consists of the non-ionic agarose and the negatively charged agaropectine thus an electroosmotic flux is observed in analytical electrophoresis. In this study the potential electroosmosis on textile reinforced agar membranes as separation method was investigated. Using a five-chamber electrolysis cell and an agar membrane/cellulose fabric composite an intensive electroosmotic flow of 1-2 ml cm(2) h(-1) at 100 mA cell current could be observed. The movement of cations in the negatively charged agar structure led to an intensive electroosmotic flux, which also transported uncharged molecules such as urea, glucose through the membrane. Separation of uncharged low molecular weight molecules is determined by the membrane characteristic. The transport of ions (K(+), PO4(3-), creatinine) and uncharged molecules (urea, glucose) in electroosmotic separation experiments was monitored using a pH 5.5 phosphate electrolyte with the aim to assess the overall transport processes in the electrochemical cell. The results demonstrate the potential of the method for filtration of biological fluids in the absence of external pressure or high shear rates. PMID:26572331

  2. Effects of immersion disinfection of agar-alginate combined impressions on the surface properties of stone casts.

    PubMed

    Iwasaki, Yukiko; Hiraguchi, Hisako; Iwasaki, Eriko; Yoneyama, Takayuki

    2016-01-01

    This study investigated the effects of disinfection of agar-alginate combined impressions on the surface properties of the resulting stone casts. Two brands of cartridge-form agar impression material and one alginate impression material were used. Agar-alginate combined impressions of smooth glass plates were prepared. The impressions were immersed in 0.55% ortho-phthalaldehyde solution or 0.5% sodium hypochlorite solution for 1, 3, 5 and 10 min. A stone cast made with an impression that had not been immersed was prepared as a control. The surface roughness (Ra) of the stone casts was measured, and the cast surfaces were observed by SEM. Immersion of agar-alginate combined impressions in 0.5% sodium hypochlorite solution for up to 10 min had no serious adverse effects on the surface properties of the stone casts. In contrast, even 1 min of immersion in 0.55% ortho-phthalaldehyde solution caused deterioration of the cast surface properties. PMID:26843442

  3. Revisiting an agar-based plate method: what the static biofilm method can offer for biofilm research.

    PubMed

    Oja, Terhi; Blomqvist, Brianna; Buckingham-Meyer, Kelli; Goeres, Darla; Vuorela, Pia; Fallarero, Adyary

    2014-12-01

    The development of biofilms in static plates was monitored. Glass coupons were placed on agar covered with filter paper, which was inoculated with suspended bacteria. The viable cell density, biofilms matrix and biomass were quantified. The method is excellent for adhesion and material studies, due to its simplicity and flexibility. PMID:25455020

  4. Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the present paper, we test the suitability of Choline-Cl/urea (DES-U) and Choline-Cl/glycerol (DES-G) eutectic mixtures at 1:2 molar ratios for the production of agar biodegradable films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and s...

  5. Polish Terms for "Blue" in the Perspective of Vantage Theory

    ERIC Educational Resources Information Center

    Stanulewicz, Danuta

    2010-01-01

    The Polish set of terms for blue includes, inter alia, the following adjectives: "niebieski" "blue", "blekitny" "(sky) blue", "granatowy" "navy blue", "lazurowy" "azure", "modry" "(intense) blue" and "siny" "(grey) violet-blue". The adjective "niebieski" is the basic term; however, it shares some of its functions with "blekitny", which is

  6. Polish Terms for "Blue" in the Perspective of Vantage Theory

    ERIC Educational Resources Information Center

    Stanulewicz, Danuta

    2010-01-01

    The Polish set of terms for blue includes, inter alia, the following adjectives: "niebieski" "blue", "blekitny" "(sky) blue", "granatowy" "navy blue", "lazurowy" "azure", "modry" "(intense) blue" and "siny" "(grey) violet-blue". The adjective "niebieski" is the basic term; however, it shares some of its functions with "blekitny", which is…

  7. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by α-chitin nanoparticles.

    PubMed

    Dhananasekaran, Solairaj; Palanivel, Rameshthangam; Pappu, Srinivasan

    2016-01-01

    Expelling of dyestuff into water resource system causes major thread to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Therefore, an attempt was made to study the adsorption of dyestuff (Methylene Blue (MB), Bromophenol Blue (BPB) and Coomassie Brilliant Blue (CBB)) by α-chitin nanoparticles (CNP) prepared from Penaeus monodon (Fabricius, 1798) shell waste. On contrary to the most recognizable adsorption studies using chitin, this is the first study using unique nanoparticles of ⩽50 nm used for the dye adsorption process. The results showed that the adsorption process increased with increase in the concentration of CNP, contact time and temperature with the dyestuff, whereas the adsorption process decreased with increase in the initial dye concentration and strong acidic pH. The results from Fourier transform infrared (FTIR) spectroscopy confirmed that the interaction between dyestuff and CNP involved physical adsorption. The adsorption process obeys Langmuir isotherm (R (2) values were 0.992, 0.999 and 0.992 for MB, BPB and CBB, and RL value lies between 0 and 1 for all the three dyes) and pseudo second order kinetics (R (2) values were 0.996, 0.999 and 0.996 for MB, BPB and CBB) more effectively. The isotherm and kinetic models confirmed that CNP can be used as a suitable adsorbent material for the removal of dyestuff from effluents. PMID:26843977

  8. Adsorption of Methylene Blue, Bromophenol Blue, and Coomassie Brilliant Blue by α-chitin nanoparticles

    PubMed Central

    Dhananasekaran, Solairaj; Palanivel, Rameshthangam; Pappu, Srinivasan

    2015-01-01

    Expelling of dyestuff into water resource system causes major thread to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Therefore, an attempt was made to study the adsorption of dyestuff (Methylene Blue (MB), Bromophenol Blue (BPB) and Coomassie Brilliant Blue (CBB)) by α-chitin nanoparticles (CNP) prepared from Penaeus monodon (Fabricius, 1798) shell waste. On contrary to the most recognizable adsorption studies using chitin, this is the first study using unique nanoparticles of ⩽50 nm used for the dye adsorption process. The results showed that the adsorption process increased with increase in the concentration of CNP, contact time and temperature with the dyestuff, whereas the adsorption process decreased with increase in the initial dye concentration and strong acidic pH. The results from Fourier transform infrared (FTIR) spectroscopy confirmed that the interaction between dyestuff and CNP involved physical adsorption. The adsorption process obeys Langmuir isotherm (R2 values were 0.992, 0.999 and 0.992 for MB, BPB and CBB, and RL value lies between 0 and 1 for all the three dyes) and pseudo second order kinetics (R2 values were 0.996, 0.999 and 0.996 for MB, BPB and CBB) more effectively. The isotherm and kinetic models confirmed that CNP can be used as a suitable adsorbent material for the removal of dyestuff from effluents. PMID:26843977

  9. Characterisation of Elastic and Acoustic Properties of an Agar-Based Tissue Mimicking Material.

    PubMed

    Brewin, M P; Birch, M J; Mehta, D J; Reeves, J W; Shaw, S; Kruse, C; Whiteman, J R; Hu, S; Kenz, Z R; Banks, H T; Greenwald, S E

    2015-10-01

    As a first step towards an acoustic localisation device for coronary stenosis to provide a non-invasive means of diagnosing arterial disease, measurements are reported for an agar-based tissue mimicking material (TMM) of the shear wave propagation velocity, attenuation and viscoelastic constants, together with one dimensional quasi-static elastic moduli and Poisson's ratio. Phase velocity and attenuation coefficients, determined by generating and detecting shear waves piezo-electrically in the range 300 Hz-2 kHz, were 3.2-7.5 ms(-1) and 320 dBm(-1). Quasi-static Young's modulus, shear modulus and Poisson's ratio, obtained by compressive or shear loading of cylindrical specimens were 150-160 kPa; 54-56 kPa and 0.37-0.44. The dynamic Young's and shear moduli, derived from fitting viscoelastic internal variables by an iterative statistical inverse solver to freely oscillating specimens were 230 and 33 kPa and the corresponding relaxation times, 0.046 and 0.036 s. The results were self-consistent, repeatable and provide baseline data required for the computational modelling of wave propagation in a phantom. PMID:25773982

  10. Development and validation of a microbiological agar assay for determination of cefuroxime sodium in pharmaceutical preparations.

    PubMed

    Schmidt, Cleber A; Agarrayua, Danielle A; Laporta, Luciane V; Machado, Jaison C; Manfio, Maria L; Bittencourt, Celso F

    2009-06-01

    Cefuroxime (CFU) is a semi-synthetic cephalosporin with a relatively broad-spectrum antimicrobial activity, and belongs to the second generation of cephalosporins. Regarding the quality control of medicines, a validated microbiological assay for determination of cefuroxime sodium in pharmaceutical formulations has not been reported yet. With this purpose, this paper reports the development and validation of a simple, sensitive, accurate and reproducible agar diffusion method to quantify CFU sodium in injectable formulations. The assay is based on the inhibitory effect of CFU upon the strain of Staphylococcus aureus ATCC 6538P used as test microorganism. The results were treated statistically by analysis of variance and were found to be linear (r=0.9998) in the selected range of 8.0-32.0 microg/ml; precise [repeatability: relative standard deviation (RSD)=1.56%; intermediate precision: between-day RSD=1.27%; between analyst RSD=1.13%] and accurate (101.58%). The bioassay specificity was studied by evaluation of degraded sample at 50 degrees C with analysis at 0, 24 and 48 h in parallel with the pharmacopeial liquid chromatography method for CFU. The results demonstrated the validity of the proposed bioassay, which allows reliable quantitation of CFU sodium in pharmaceutical samples and therefore can be used as a useful alternative methodology for the routine quality control of this medicine. PMID:19344741

  11. Fungistatic activity of flaxseed in potato dextrose agar and a fresh noodle system.

    PubMed

    Xu, Yingying; Hall, Clifford; Wolf-Hall, Charlene; Manthey, Frank

    2008-02-10

    Although numerous researchers have studied flaxseed as a food ingredient for its health benefits, flaxseed (Linum usitatissimum) has never been considered as a food preservative. The objective of this study was to investigate the effect of flaxseed flour (FF) concentration (0, 6, 9, 12, and 15% wt/wt), cultivar ('Omega' and brown) and source (four seed companies located in Minnesota and North Dakota) on flaxseed fungistatic activity. Fungal radial growth was used to assess the fungistatic activity of FF in both potato dextrose agar (PDA) medium and a fresh noodle system. Strains of Penicillium chrysogenum, Aspergillus flavus, Fusarium graminearum, and a Penicillium sp. isolated from molded noodles were used as the test microorganisms. Results showed that growth of F. graminearum was completely inhibited at all FF concentrations in PDA, and the inhibition of the other three test microorganisms increased with increasing FF concentrations. In the model noodle system, FF concentration at 9% or higher significantly reduced the mold count of fresh noodle during storage. In the inoculated noodle system, 6% FF addition was sufficient to significantly inhibit the growth of F. graminearum and A. flavus, whereas 9% FF concentrations showed fungistatic activity against P. chrysogenum and the Penicillium sp. isolate. Differences in the degree of mold inhibition were found among FFs obtained from different sources and cultivars. Results suggested that flaxseed possesses fungistatic activity and could be used as a multifunctional food ingredient. PMID:18077042

  12. Dichromated agar: a promising doped biocopolymer for real time holographic recording

    NASA Astrophysics Data System (ADS)

    Bolte, Michèle; Israëli, Yaël; Rivaton, Agnès; Lessard, Roger A.

    2006-09-01

    Agar is a natural polysaccharide which, when doped with dichromate ammonium, can be considered as a promising light sensitive material used for real time hologram recording. The volume transmission gratings were recorded with a Kypton laser at 413 nm and they were read in real-time with a He/Ne laser at 632.8 nm contrary to dichromated gelatin. The so obtained holograms formed were phase holograms due to a refraction index modulation. The optimisation of chemical and physical parameters was investigated in order to form high quality holograms. It was demonstrated the crucial role played by the remaining water in the final film on the value of the diffraction efficiency. In the optimal conditions, a maximum diffraction efficiency of 37 % was attained. Both on-off experiments and the storage of the exposed materials at room temperature and in the dark reveal that the holograms were stable. An attempt to rationalize the set of results in terms of chemical structure of the polymeric matrix and of its ability to stabilize chromium (V) is presented.

  13. Mercury and its bioconcentration factors in fly agaric (Amanita muscaria) from spatially distant sites in Poland.

    PubMed

    Falandysz, J; Lipka, K; Mazur, A

    2007-09-01

    Total mercury content has been determined in the fruiting bodies of fly agaric (Amanita muscaria) and topsoil layer (0-10 cm) collected from 14 spatially distant sites across Poland. Mercury was measured by cold-vapor atomic absorption spectroscopy (CV-AAS) after nitric acid (mushrooms) or nitric acid and sulfuric acid (soil) digestion of the samples. The caps, depending on the site, contained total mercury at mean concentrations from 0.24+/-0.13 to 1.4+/-0.6 microg/g dm (median 0.19-1.4 microg/g dm), and stalks from 0.18+/-0.06 to 0.71+/-0.26 microg/g dm (median 0.18-0.67 microg/g dm). An overall-mean the total mercury content for 204 caps and stalks was, respectively, 0.73+/-0.55 (0.05-3.3 microg/g dm) and 0.43+/-0.33 (0.09-2.3 microg/g dm). PMID:17849304

  14. Theoretical and experimental NMR studies on muscimol from fly agaric mushroom (Amanita muscaria).

    PubMed

    Kupka, Teobald; Wieczorek, Piotr P

    2016-01-15

    In this article we report results of combined theoretical and experimental NMR studies on muscimol, the bioactive alkaloid from fly agaric mushroom (Amanita muscaria). The assignment of (1)H and (13)C NMR spectra of muscimol in DMSO-d6 was supported by additional two-dimensional heteronuclear correlated spectra (2D NMR) and gauge independent atomic orbital (GIAO) NMR calculations using density functional theory (DFT). The effect of solvent in theoretical calculations was included via polarized continuum model (PCM) and the hybrid three-parameter B3LYP density functional in combination with 6-311++G(3df,2pd) basis set enabled calculation of reliable structures of non-ionized (neutral) molecule and its NH and zwitterionic forms in the gas phase, chloroform, DMSO and water. GIAO NMR calculations, using equilibrium and rovibrationally averaged geometry, at B3LYP/6-31G* and B3LYP/aug-cc-pVTZ-J levels of theory provided muscimol nuclear magnetic shieldings. The theoretical proton and carbon chemical shifts were critically compared with experimental NMR spectra measured in DMSO. Our results provide useful information on its structure in solution. We believe that such data could improve the understanding of basic features of muscimol at atomistic level and provide another tool in studies related to GABA analogs. PMID:26312739

  15. Theoretical and experimental NMR studies on muscimol from fly agaric mushroom (Amanita muscaria)

    NASA Astrophysics Data System (ADS)

    Kupka, Teobald; Wieczorek, Piotr P.

    2016-01-01

    In this article we report results of combined theoretical and experimental NMR studies on muscimol, the bioactive alkaloid from fly agaric mushroom (Amanita muscaria). The assignment of 1H and 13C NMR spectra of muscimol in DMSO-d6 was supported by additional two-dimensional heteronuclear correlated spectra (2D NMR) and gauge independent atomic orbital (GIAO) NMR calculations using density functional theory (DFT). The effect of solvent in theoretical calculations was included via polarized continuum model (PCM) and the hybrid three-parameter B3LYP density functional in combination with 6-311++G(3df,2pd) basis set enabled calculation of reliable structures of non-ionized (neutral) molecule and its NH and zwitterionic forms in the gas phase, chloroform, DMSO and water. GIAO NMR calculations, using equilibrium and rovibrationally averaged geometry, at B3LYP/6-31G* and B3LYP/aug-cc-pVTZ-J levels of theory provided muscimol nuclear magnetic shieldings. The theoretical proton and carbon chemical shifts were critically compared with experimental NMR spectra measured in DMSO. Our results provide useful information on its structure in solution. We believe that such data could improve the understanding of basic features of muscimol at atomistic level and provide another tool in studies related to GABA analogs.

  16. Evaluation of Brilliance ESBL Agar, a Novel Chromogenic Medium for Detection of Extended-Spectrum-Beta- Lactamase-Producing Enterobacteriaceae▿

    PubMed Central

    Huang, Te-Din; Bogaerts, Pierre; Berhin, Catherine; Guisset, Amelie; Glupczynski, Youri

    2010-01-01

    The aim of this study was to evaluate the performance of Brilliance ESBL agar (OX; Oxoid, Basingstoke, United Kingdom), a novel chromogenic agar for the selective isolation and the presumptive identification of extended-spectrum-beta-lactamase (ESBL)-producing Enterobacteriaceae. A panel of 200 clinical Gram-negative Enterobacteriaceae and nonfermenting isolates with defined resistance mechanisms was inoculated onto OX and onto ChromID ESBL agar (BM; bioMérieux, Marcy l'Etoile, France) chromogenic medium in the first part of the study to evaluate the growth selectivity and chromogenic features of these two media. Of the 156 Enterobacteriaceae challenge isolates, 8 fully susceptible isolates were inhibited, all 98 ESBL producers were detected, and 50 isolates harboring other resistance mechanisms were recovered on both chromogenic agars. In the second phase, 528 clinical samples (including 344 fecal specimens) were plated onto OX, BM, and MacConkey agar with a ceftazidime disk (MCC) for the screening of ESBL-producing Enterobacteriaceae. Growth on at least one medium was observed with 144 (27%) of the clinical samples screened. A total of 182 isolates, including 109 (60%) of Enterobacteriaceae, were recovered and 70 of these (from 59 specimens) were confirmed as ESBL-producing isolates. The sensitivities of MCC, BM, and OX were 74.6%, 94.9%, and 94.9%, respectively. The specificities of MCC, BM, and OX by specimens reached 94.9%, 95.5%, and 95.7%, respectively, when only colored colonies were considered on the two selective chromogenic media. The high negative predictive value (99.3%) found for OX suggests that this medium may constitute an excellent screening tool for the rapid exclusion of patients not carrying ESBL producers. PMID:20410342

  17. Spectroscopy of blue stellar objects

    NASA Technical Reports Server (NTRS)

    Mitchell, K. J.; Warnock, A., III; Nations, H. L.; Barden, S. C.

    1983-01-01

    Spectra have been obtained for the brightest objects from a list of blue stellar objects found in a Palomar Schmidt field centered on Kapteyn Selected Area 28. Four of the objects presented here comprise a complete sample of objects with UV excess and magnitudes brighter than or equal to B = 16.3 mag. The object with the largest UV excess is a previously undiscovered quasar of redshift 0.25 and cataloged B magnitude of 15.6 mag. The object shows some evidence of variability. Spectroscopy for one bright object in a companion field centered on Selected Area 29 is also presented.

  18. Comparison of Six Chromogenic Agar Media for the Isolation of a Broad Variety of Non-O157 Shigatoxin-Producing Escherichia coli (STEC) Serogroups

    PubMed Central

    Verhaegen, Bavo; De Reu, Koen; Heyndrickx, Marc; De Zutter, Lieven

    2015-01-01

    The isolation of non-O157 STEC from food samples has proved to be challenging. The selection of a suitable selective isolation agar remains problematic. The purpose of this study was to qualitatively and quantitatively evaluate six chromogenic agar media for the isolation of STEC: Tryptone Bile X-glucuronide agar (TBX), Rainbow® Agar O157 (RB), Rapid E. coli O157:H7 (RE), Modified MacConkey Agar (mMac), CHROMagarTM STEC (Chr ST) and chromIDTM EHEC (Chr ID). During this study, 45 E. coli strains were used, including 39 STEC strains belonging to 16 different O serogroups and 6 non-STEC E. coli. All E. coli strains were able to grow on TBX and RB, whereas one STEC strain was unable to grow on Chr ID and a number of other STEC strains did not grow on mMac, CHROMagar STEC and Rapid E. coli O157:H7. However, only the latter three agars were selective enough to completely inhibit the growth of the non-STEC E. coli. Our conclusion was that paired use of a more selective agar such as CHROMagar STEC together with a less selective agar like TBX or Chr ID might be the best solution for isolating non-O157 STEC from food. PMID:26090610

  19. Equivalency testing of TTC Tergitol 7 agar (ISO 9308-1:2000) with five culture media for the detection of E. coli in water samples in Greece.

    PubMed

    Mavridou, A; Smeti, E; Mandilara, G; Mandilara, G; Boufa, P; Vagiona-Arvanitidou, M; Vantarakis, A; Vassilandonopoulou, G; Pappa, O; Roussia, V; Tzouanopoulos, A; Livadara, M; Aisopou, I; Maraka, V; Nikolaou, E; Mandilara, G

    2010-01-01

    In this study ten laboratories in Greece compared the performance of reference method TTC Tergitol 7 Agar (with the additional test of beta-glucuronidase production) with five alternative methods, to detect E. coli in water, in line with European Water Directive recommendations. The samples were prepared by spiking drinking water with sewage effluent following a standard protocol. Chlorinated and non-chlorinated samples were used. The statistical analysis was based on the mean relative difference of confirmed counts and was performed in line with ISO 17994. The results showed that in total, three of the alternative methods (Chromocult Coliform agar, Membrane Lauryl Sulfate agar and Trypton Bilex-glucuronidase medium) were not different from TTC Tergitol 7 agar (TTC Tergitol 7 agar vs Chromocult Coliform agar, 294 samples, mean RD% 5.55; vs MLSA, 302 samples, mean RD% 1; vs TBX, 297 samples, mean RD% -2.78). The other two alternative methods (Membrane Faecal coliform medium and Colilert 18/ Quantitray) gave significantly higher counts than TTC Tergitol 7 agar (TTC Tergitol 7 agar vs MFc, 303 samples, mean RD% 8.81; vs Colilert-18/Quantitray, 76 samples, mean RD% 18.91). In other words, the alternative methods generated performance that was as reliable as, or even better than, the reference method. This study will help laboratories in Greece overcome culture and counting problems deriving from the EU reference method for E. coli counts in water samples. PMID:20057092

  20. Use of agar diffusion assay to evaluate bactericidal activity of formulations of alkaline salts of fatty acids against bacteria associated with poultry processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agar diffusion assay was used to examine antibacterial activity of alkaline salts of fatty acids (FA). Wells in agar media seeded with bacteria were filled with FA-potassium hydroxide (KOH) solutions, plates were incubated, and zones of inhibition were measured. The relationship between bacteric...

  1. In vitro antifungal susceptibility testing of Scopulariopsis brevicaulis strains using agar diffusion method.

    PubMed

    Skóra, Magdalena; Macura, Anna B

    2011-01-01

    The genus Scopulariopsis is a common soil saprotroph and has been isolated from air, organic waste and also from plant, animal and human tissues. Scopulariopsis has mainly been associated in humans with superficial mycoses, but it has also been described as the cause of subcutaneous and invasive infections. The most common aetiological agent of infections in humans is Scopulariopsis brevicaulis. This species has been reported to be resistant in vitro to broad-spectrum antifungal agents available today. The aim of the study was to establish in vitro antifungal susceptibility of 35 S. brevicaulis strains against amphotericin B (AMB), flucytosine (FC), caspofungin (CAS), terbinafine (TER), ciclopirox (CIC), voriconazole (VOR), clotrimazole (CTR), miconazole (MCZ), econazole (ECO), ketoconazole (KET), itraconazole (ITR), and fluconazole (FLU). Antifungal susceptibility tests were evaluated by an agar diffusion method (Neo-Sensitabs, Rosco, Denmark). AMB, FC, CAS, ITR and FLU showed no antifungal activity against S. brevicaulis. TER, CIC, CTR, KET, VOR, ECO, and MCZ revealed inhibitory activity for S. brevicaulis, but it varied for each of the drugs. The best antifungal effect was observed for TER and CIC. All isolates had large inhibition zones for TER and CIC. CTR was also inhibitory for all tested S. brevicaulis isolates, but the diameters of inhibition zones were smaller than for TER and CIC. Nearly 89% isolates showed inhibition zones for KET and the mean diameter of the inhibition zone was comparable to CTR. The least antifungal activity exhibited VQR, ECO and MCZ. Because of the multiresistance of S. brevicaulis, infections due to this species may not respond to particular antifungal treatment and other therapeutic approaches should be considered, e.g., combined therapy and/or surgery. PMID:21682097

  2. Evaluation of the antibacterial effects of vancomycin hydrochloride released from agar-gelatin-bioactive glass composites.

    PubMed

    Rivadeneira, Josefina; Di Virgilio, Ana Laura; Audisio, M Carina; Boccaccini, Aldo R; Gorustovich, Alejandro A

    2015-02-01

    The aim of this work was to evaluate the perfomance of agar-gelatin (AG) composites and AG-containing 45S5 bioactive glass (BG) microparticles (AGBG) in relation to their water uptake capacity, sustained release of a drug over time, and antibacterial effects. The composites were fabricated by the gel-casting method. To impart the local drug release capacity, vancomycin hydrochloride (VC) was loaded in the composites in concentrations of 0.5 and 1 mg ml(-1). VC release was assessed in distilled water at 37 °C up to 72 h and quantified spectrophotometrically. The antibacterial activity of composites was evaluated by the inhibition zone test and the plate count method. The experiments were performed in vitro up to 48 h on three staphylococcus strains: Staphylococcus aureus ATCC29213, S. aureus ATCC6538 and Staphylococcus epidermidis ATCC12228. The results showed that the addition of BG to AG composites did not affect the degree of water uptake. The release of VC was significantly affected by the presence of BG. VC release was higher from AGBGVC films than from AGVC ones over prolonged incubation times. Bacterial inhibition zones were found around the composites. The halos were larger when the cells were put in contact with AGVC composites than when they were put in contact with AGBGVC ones. Nevertheless, the viable count method demonstrated that the composites inhibited Staphylococcus cell growth with no statistical differences. In conclusion, the addition of BG did not reflect an improvement in the parameters studied. On the other hand, composites loaded with VC would have a role in prophylaxis against bacterial infection. PMID:25586240

  3. Comparative performance of Thin Layer Agar and Löwenstein-Jensen culture for diagnosis of tuberculosis.

    PubMed

    Battaglioli, T; Rintiswati, N; Martin, A; Palupi, K R; Bernaerts, G; Dwihardiani, B; Ahmad, R A; Matthys, F; Mahendradhata, Y; Van der Stuyft, P

    2013-11-01

    Sputum smear microscopy for the diagnosis of tuberculosis (TB) is cheap and simple but its sensitivity is low. Culture on Löwenstein-Jensen (LJ) is more sensitive but it takes a long time to yield results. Thin-Layer Agar (TLA) culture was suggested as an equally sensitive and faster alternative. We evaluated the performance of TLA for diagnosing TB in Jogjakarta, Indonesia. People with suspected TB presenting from July 2010 to July 2011 to two chest clinics of the National TB Control Programme network of Jogjakarta were eligible for inclusion. A sputum sample was sent to the Gadjah Mada University microbiology laboratory for concentration, smearing, Ziehl-Neelsen staining and culture on LJ and TLA. Sensitivity of cultures was evaluated against a composite reference standard (any positive culture). Time to detection of Mycobacteria was recorded. Out of 1414 samples, 164 (12%) were smear positive, 99 (7%) were scanty and 1151 (81%) were negative. On TLA and LJ respectively, 168 (12%) and 149 (11%) samples were positive, 72 (5%) and 32 (2%) were contaminated (κ = 0.64; 95% CI 0.59-0.69, p <0.01). Using the reference standard, 196 (14%) TB cases were identified. The sensitivity of TLA was 0.86 (95% CI 0.80-0.90), significantly higher (p 0.03) than for LJ (0.76; 95% CI 0.69-0.81). The median time to detection in days was significantly shorter (p <0.01) for TLA (12; 95% CI 11-13) than for LJ (44; 95% CI 43-45). TLA is a rapid and sensitive method for the diagnosis of TB. Implementation studies to evaluate the cost-effectiveness and impact of its introduction into programmatic settings are urgently needed. PMID:23738759

  4. Preparation and application of agar/alginate/collagen ternary blend functional food packaging films.

    PubMed

    Wang, Long-Feng; Rhim, Jong-Whan

    2015-09-01

    Ternary blend agar/alginate/collagen (A/A/C) hydrogel films with silver nanoparticles (AgNPs) and grapefruit seed extract (GSE) were prepared. Their performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water contact angle (CA), water swelling ratio (SR), water solubility (WS), and antimicrobial activity were determined. The A/A/C film was highly transparent, and both AgNPs and GSE incorporated blend films (A/A/C(AgNPs) and A/A/C(GSE)) exhibited UV-screening effect, especially, the A/A/C(GSE) film had high UV-screening effect without sacrificing the transmittance. In addition, the A/A/C blend films formed efficient hydrogel film with the water holding capacity of 23.6 times of their weight. Both A/A/C(AgNPs) and A/A/C(GSE) composite films exhibited strong antimicrobial activity against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) food-borne pathogenic bacteria. The test results of fresh potatoes packaging revealed that all the A/A/C ternary blend films prevented forming of condensed water on the packaged film surface, both A/A/C(AgNPs) and A/A/C(GSE) composite films prevented greening of potatoes during storage. The results indicate that the ternary blend hydrogel films incorporated with AgNPs or GSE can be used not only as antifogging packaging films for highly respiring fresh agriculture produce, but also as an active food packaging system utilizing their strong antimicrobial activity. PMID:26187189

  5. Geothermal Technologies Program Blue Ribbon Panel Recommendations

    SciTech Connect

    none,

    2011-06-17

    The Geothermal Technologies Program assembled a geothermal Blue Ribbon Panel on March 22-23, 2011 in Albuquerque, New Mexico for a guided discussion on the future of geothermal energy in the United States and the role of the DOE Program. The Geothermal Blue Ribbon Panel Report captures the discussions and recommendations of the experts. An addendum is available here: http://www.eere.energy.gov/geothermal/pdfs/gtp_blue_ribbon_panel_report_addendum10-2011.pdf

  6. Morphological responses of wheat to blue light.

    PubMed

    Barnes, C; Bugbee, B

    1992-01-01

    Blue light significantly increased tillering in wheat (Triticum aestivum L.) plants grown at the same photosynthetic photon flux (PPF). Plants were grown under two levels of blue light (400-500 nm) in a controlled environment with continuous irradiation. Plants received either 50 micromoles m-2 s-1 of blue light or 2 micromoles m-2 s-1 blue light from filtered metal halide lamps at a total irradiance of 200 micromoles m-2 s-1 PPF (400-700 nm). Plants tillered an average of 25% more under the higher level of blue light. Blue light also caused a small, but consistent, increase in main culm development, measured as Haun stage. Leaf length was reduced by higher levels of blue light, while plant dry-mass was not significantly affected by blue light. Applying the principle of equivalent light action, the results suggest that tillering and leaf elongation are mediated by the blue-UV light receptor(s) because phytochrome photoequilibrium for each treatment were nearly identical. PMID:11537086

  7. Polymer stabilized and dispersed blue phases

    NASA Astrophysics Data System (ADS)

    Kemiklioglu, Emine

    Blue phase liquid crystal (BPLC) materials have potential for advanced applications of display material and technology based on their optical behaviors, such as field-induced birefringence and sub-millisecond response time, which is at least one order of magnitude faster than the present nematic liquid crystal based displays. Since blue phases appear in the narrow temperature range between the chiral nematic and the isotropic phases, there is a temperature range limitation for the application of blue phase liquid crystal. In this dissertation, we have developed blue phase liquid crystal materials with a wide temperature range and low driving voltage. The first goal was to develop wide-temperature range blue phase liquid crystal materials using several stabilization methods notably polymer stabilization, doping of carbon-nanotubes and bent-core molecules. The temperature range could be expanded more than 54°C via the polymer stabilization. The second goal was to explore the polymer dispersed blue phase liquid crystal combining the advantages of the polymer dispersion method and blue phase materials. Polymer encapsulated blue phase films showed a large Kerr constant, low switching voltage and fast response time. Moreover, the temperature range of encapsulated blue phase films were successfully expanded from 9°C to 54°C .

  8. Morphological responses of wheat to blue light

    NASA Technical Reports Server (NTRS)

    Barnes, C.; Bugbee, B.

    1992-01-01

    Blue light significantly increased tillering in wheat (Triticum aestivum L.) plants grown at the same photosynthetic photon flux (PPF). Plants were grown under two levels of blue light (400-500 nm) in a controlled environment with continuous irradiation. Plants received either 50 micromoles m-2 s-1 of blue light or 2 micromoles m-2 s-1 blue light from filtered metal halide lamps at a total irradiance of 200 micromoles m-2 s-1 PPF (400-700 nm). Plants tillered an average of 25% more under the higher level of blue light. Blue light also caused a small, but consistent, increase in main culm development, measured as Haun stage. Leaf length was reduced by higher levels of blue light, while plant dry-mass was not significantly affected by blue light. Applying the principle of equivalent light action, the results suggest that tillering and leaf elongation are mediated by the blue-UV light receptor(s) because phytochrome photoequilibrium for each treatment were nearly identical.

  9. Screening for ligninolytic enzymes from autochthonous fungi and applications for decolorization of Remazole Marine Blue

    PubMed Central

    Erden, Emre; Ucar, M. Cigdem; Gezer, Tekin; Pazarlioglu, Nurdan Kasikara

    2009-01-01

    This study presents new and alternative fungal strains for the production of ligninolytic enzymes which have great potential to use in industrial and biotechnological processes. Thirty autochthonous fungal strains were harvested from Bornova-Izmir in Turkiye. In the fresh fruitbody extracts laccase, manganese peroxidase and lignin peroxidase activities, which are the principal enzymes responsible for ligninocellulose degradation by Basidiomycetes, were screened. Spores of some of the basidiomycetes species such as Cortinarius sp., Trametes versicolor, Pleurotus ostreatus, Abortiporus biennis, Lyophyllum subglobisporium, Ramaria stricta, Ganoderma carnosum, Lactarius delicious ve Lepista nuda were isolated and investigated optimum cultivation conditions in submerged fermentation for high yields of ligninolytic enzyme production. In addition, isolated fungal strains were monitored on agar plates whether having the capability of decolorization of a textile dye Remazol Marine Blue. PMID:24031371

  10. Alternative to the soft-agar assay that permits high-throughput drug and genetic screens for cellular transformation

    PubMed Central

    Rotem, Asaf; Janzer, Andreas; Izar, Benjamin; Ji, Zhe; Doench, John G.; Garraway, Levi A.; Struhl, Kevin

    2015-01-01

    Colony formation in soft agar is the gold-standard assay for cellular transformation in vitro, but it is unsuited for high-throughput screening. Here, we describe an assay for cellular transformation that involves growth in low attachment (GILA) conditions and is strongly correlated with the soft-agar assay. Using GILA, we describe high-throughput screens for drugs and genes that selectively inhibit or increase transformation, but not proliferation. Such molecules are unlikely to be found through conventional drug screening, and they include kinase inhibitors and drugs for noncancer diseases. In addition to known oncogenes, the genetic screen identifies genes that contribute to cellular transformation. Lastly, we demonstrate the ability of Food and Drug Administration-approved noncancer drugs to selectively kill ovarian cancer cells derived from patients with chemotherapy-resistant disease, suggesting this approach may provide useful information for personalized cancer treatment. PMID:25902495

  11. Effect of EDTA on Pb(II) Uptake and Translocation by Tumbleweed (Salsola Kali): Agar and Hydroponics Studies

    SciTech Connect

    de la Rosa, Guadalupe; Gardea-Torresdey, Jorge L.; Peralta-Videa, Jose R.; Aldrich, Mary

    2004-03-31

    Environmental accumulation of Pb represents a worldwide health hazard. While conventional cleanup techniques are generally expensive and soil disturbing, phytoremediation represents an inexpensive friendly option for the removal of contaminants from soil and water. In this research, tumbleweed (Salsola kali) plants exposed for 15 days to Pb(NO3)2 at 80 and 125 ppm in hydroponics and agar media, demonstrated a high capacity to uptake lead. The results showed that the plants cultivated in agar accumulated 25563, 5534 and 2185 mg Pb kg-1 DW in roots, stems and leaves, respectively. Moreover, Pb concentrations found in hydroponically grown tumbleweed plants tissues were 30744, 1511 and 1421 mg kg-1 DW in roots, stems and leaves, respectively. It was observed that EDTA enhanced Pb translocation. No Pb phytotoxic effects were observed during the experimental time period. Cellular structural features were also observed using TEM.

  12. [Tryptose sulphite cycloserine agar for the recovery of Clostridium perfringens in surface waters: a study of different modes of utilization].

    PubMed

    Nusca, A; Orefice, L; Paradiso, R

    2007-01-01

    In the recent European Drinking Water Directive, Clostridium perfringens has assumed increasing importance so as to be considered a primary contamination indicator. Therefore it emerged the necessity to make culture methods, aimed at its recovery, more specific and sensitive. In this study we have verified the ability of Tryptose Sulphite Cycloserine Agar plates (TSC Agar), prepared and stored before the use at refrigeration temperature (+4 degrees) for different times, to show typical colonies, using both, the single layer and double layer techniques. Results show that storage of the prepared medium, even for a few days, decrease the recovery of typical colonies although such negative effect is minimized by using the double layer technique. PMID:17405507

  13. Diffusion in immobilized-cell agar layers: influence of bacterial growth on the diffusivity of potassium chloride.

    PubMed

    Mignot, L; Junter, G A

    1990-05-01

    The diffusivity of potassium chloride in composite agar slab/microporous membrane structures loaded with various amounts of Escherichia coli whole cells was determined using both time-lag and steady-state methods. The diffusion coefficient of KCl decreased linearly with the logarithm of the immobilized-cell content. The effect exerted by bacterial growth inside the immobilization matrices on KCl diffusivity was then investigated. The diffusion coefficient of KCl obtained by time-lag analysis decreased during incubation of the immobilized-cell structures, whereas less consistent results arose from the steady-state method. An apparent doubling time for immobilized E. coli, increasing with the initial cell content of the gel, was obtained from the calibration relationship between KCl diffusivity and the number of organisms in agar. PMID:1366531

  14. [Clinical symptoms and circumastances of acute poisonings with fly agaric (Amanita muscaria) and panther cap (Amanita pantherina)].

    PubMed

    Łukasik-Głebocka, Magdalena; Druzdz, Artur; Naskret, Maciej

    2011-01-01

    Mushroom poisonings in Poland are quite common, especially in summer and autumn, but fly agaric (Amanita muscaria) and panther cap (Amanita pantherina) are rather rare cause of these intoxications. Fly agaric is a cause of deliberate poisoning, whereas panther cap poisoning also happens accidentally. The main toxins of these two mushrooms are ibotenic acid (pantherine, agarine), muscimol, muscazone and muscaridine. The other bioactive substances are stizolobic and stizolobinic acids and aminodicarboxyethylthiopropanoic acids. All these compounds are responsible for diverse picture of intoxication. An analysis of patients with Amanita muscaria and Amanita pantherina poisoning hospitalized in the Poznan Departament of Toxicology revealed that symptoms occurred after 30 minutes to 2 hours with vomiting, hallucinations, restlessness, increased psychomotor drive and central nervous system depression. Other antycholinergic symptoms like tachycardia and increased blood pressure, mydriasis, dry and red skin were seen only in a few cases. Acute respiratory failure was the most dangerous symptom observed in the course of poisoning. PMID:22010435

  15. Use of hydrogen peroxide treatment and crystal violet agar plates for selective recovery of bacteriophages from natural environments

    SciTech Connect

    Asghari, A.; Farrah, S.R.; Bitton, G. )

    1992-04-01

    Hydrogen peroxide inactivated bacteriophages and bacteria at different rates. A concentration of 0.1% hydrogen peroxide reduced the numbers of several bacteria by an average of 94% but caused an average of 25% inactivation in the numbers of bacteriophages tested. Treating natural samples with hydrogen peroxide selectively reduced the indigenous bacterial flora and permitted better visualization of plaques of lawns of Escherichia coli C-3000. In some cases indigenous gram-positive bacteria were relatively resistant to hydrogen peroxide, but their growth could be limited by incorporation of crystal violet into the bottom agar used for plaque assays. The use of hydrogen peroxide treatment and crystal violet-containing plates permitted recovery of more phages from natural samples than did other procedures, such as chloroform pretreatment or the use of selective plating agar such as EC medium.

  16. Cytological comparison of leaves and stems of Prunus avium L. shoots cultured on a solid medium with agar or gelrite.

    PubMed

    Franck, T; Crvecoeur, M; Wuest, J; Greppin, H; Gaspar, T

    1998-01-01

    An axillary proliferating clone of Prunus avium L. was subcultured every four weeks on solid MS medium with agar as the gelling agent. Vitrification (hyperhydricity) of shoots was induced in one four week cycle with the same medium except that agar was replaced by gelrite. During culture on the vitrifying medium, the water content of the shoots progressively increased with a parallel decrease in chlorophyll content. Cytological differences between the leaves and stems of the vitrified and normal shoots were detected by light and electron (both transmission and scanning) microscopy. Leaves of vitrified shoots were characterized by lower number of chloroplasts in the palisade parenchyma and by a defective cuticle. The stems of vitrified shoots had a less developed and lignifled xylem tissue, lacked sclerenchymatic areas and showed hypertrophy of the cortical parenchyma. More intense vacuolar activity with evaginations of the chloroplast envelope into the vacuole was noted in cells of vitrified leaves. PMID:9554582

  17. Preparation of agar nanospheres: comparison of response surface and artificial neural network modeling by a genetic algorithm approach.

    PubMed

    Zaki, Mohammad Reza; Varshosaz, Jaleh; Fathi, Milad

    2015-05-20

    Multivariate nature of drug loaded nanospheres manufacturing in term of multiplicity of involved factors makes it a time consuming and expensive process. In this study genetic algorithm (GA) and artificial neural network (ANN), two tools inspired by natural process, were employed to optimize and simulate the manufacturing process of agar nanospheres. The efficiency of GA was evaluated against the response surface methodology (RSM). The studied responses included particle size, poly dispersity index, zeta potential, drug loading and release efficiency. GA predicted greater extremum values for response factors compared to RSM. However, real values showed some deviations from predicted data. Appropriate agreement was found between ANN model predicted and real values for all five response factors with high correlation coefficients. GA was more successful than RSM in optimization and along with ANN were efficient tools in optimizing and modeling the fabrication process of drug loaded in agar nanospheres. PMID:25817674

  18. [An observation on the histological structure of Oncomelania hupensis soft tissue by agar-paraffin double-embedding method].

    PubMed

    Tan, Ping; Zhang, Jie; Li, Qing; Yu, Zhi-jun

    2014-12-01

    In order to study the histological structure of Oncomelania hupensis soft tissue, the fixed soft tissues of O. hupensis were pre-embedded in the agar and made blocks, then dehydrated, transparentized, immersed in paraffin, sectioned, and stained with haematoxylin-eosin (HE). Permanent slides of O. hupensis soft tissue were obtained. The histological structure of soft tissues was clear under the microscope. PMID:25902672

  19. Wrinkly-Spreader fitness in the two-dimensional agar plate microcosm: maladaptation, compensation and ecological success.

    PubMed

    Spiers, Andrew J

    2007-01-01

    Bacterial adaptation to new environments often leads to the establishment of new genotypes with significantly altered phenotypes. In the Wrinkly Spreader (WS), ecological success in static liquid microcosms was through the rapid colonisation of the air-liquid interface by the production of a cellulose-based biofilm. Rapid surface spreading was also seen on agar plates, but in this two-dimensional environment the WS appears maladapted and rapidly reverts to the ancestral smooth (SM)-like colony genotype. In this work, the fitness of WS relative to SM in mixed colonies was found to be low, confirming the WS instability on agar plates. By examining defined WS mutants, the maladaptive characteristic was found to be the expression of cellulose. SM-like revertants had a higher growth rate than WS and no longer expressed significant amounts of cellulose, further confirming that the expression of this high-cost polymer was the basis of maladaptation and the target of compensatory mutation in developing colonies. However, examination of the fate of WS-founded populations in either multiple-colony or single mega-colony agar plate microcosms demonstrated that the loss of WS lineages could be reduced under conditions in which the rapid spreading colony phenotype could dominate nutrient and oxygen access more effectively than competing SM/SM-like genotypes. WS-like isolates recovered from such populations showed increased WS phenotype stability as well as changes in the degree of colony spreading, confirming that the WS was adapting to the two-dimensional agar plate microcosm. PMID:17710140

  20. Isolation of Shiga Toxin-Producing Escherichia coli from Ground Beef Using Multiple Combinations of Enrichment Broths and Selective Agars.

    PubMed

    Brusa, Victoria; Piñeyro, Pablo E; Galli, Lucía; Linares, Luciano H; Ortega, Emanuel E; Padola, Nora L; Leotta, Gerardo A

    2016-03-01

    Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens, and beef cattle are recognized as the principal reservoir. The aims of this study were (1) to identify the most sensitive combination of selective enrichment broths and agars for STEC isolation in artificially inoculated ground beef samples, and (2) to evaluate the most efficient combination(s) of methods for naturally contaminated ground beef samples. A total of 192 ground beef samples were artificially inoculated with STEC and non-stx bacterial strains. A combination of four enrichment broths and three agars were evaluated for sensitivity, specificity, and positive predictive value for STEC isolation from experimentally inoculated samples. Enrichments with either modified tryptic soy broth (mTSB) containing 8 mg/L novobiocin (mTSB-8) or modified Escherichia coli (mEC) broth followed by isolation in MacConkey agar were the most sensitive combinations for STEC isolation of artificially inoculated samples. Independently, both enrichments media followed by isolation in MacConkey were used to evaluate ground beef samples from 43 retail stores, yielding 65.1% and 58.1% stx-positive samples by RT-PCR, respectively. No difference was observed in the isolate proportions between these two methods (8/25 [32%] and 8/28 [28.6%]). Identical serotypes and stx genotypes were observed in STEC strains isolated from the same samples by either method. In this study, no single enrichment protocol was sufficient to detect all STEC in artificially inoculated samples and had considerable variation in detection ability with naturally contaminated samples. Moreover, none of the single or combinations of multiple isolation agars used were capable of identifying all STEC serogroups in either artificially inoculated or naturally occurring STEC-contaminated ground beef. Therefore, it may be prudent to conclude that there is no single method or combination of isolation methods capable of identifying all STEC serogroups. PMID:26836701

  1. Epidemiology of Klebsiella oxytoca-Associated Diarrhea Detected by Simmons Citrate Agar Supplemented with Inositol, Tryptophan, and Bile Salts

    PubMed Central

    Cheng, Vincent C. C.; Yam, Wing-Cheong; Tsang, Lee-Lee; Yau, Miranda C. Y.; Siu, Gilman K. H.; Wong, Sally C. Y.; Chan, Jasper F. W.; To, Kelvin K. W.; Tse, Herman; Hung, Ivan F. N.; Tai, Josepha W. M.; Ho, Pak-Leung

    2012-01-01

    We studied the clinical and epidemiological characteristics of Klebsiella oxytoca-associated diarrhea in hospitalized patients in Hong Kong. Between 1 November 2009 and 30 April 2011, all inositol-fermenting colonies found on Simmons citrate agar supplemented with inositol, tryptophan, and bile salts (SCITB agar) used for the culturing of diarrheal stool samples were screened by a spot indole test for K. oxytoca. The overall sensitivity of SCITB agar plus the spot indole test (93.3%) for the detection of K. oxytoca in stool samples was superior to that of MacConkey agar (63.3%), while the specificities were 100% and 60.4%, respectively. The former achieved a 23-fold reduction in the workload and cost of subsequent standard biochemical identifications. Cytotoxin production and the clonality of K. oxytoca were determined by a cell culture cytotoxicity neutralization assay using HEp-2 cells and pulsed-field gel electrophoresis (PFGE), respectively. Of 5,581 stool samples from 3,537 patients, K. oxytoca was cultured from 117/5,581 (2.1%) stool samples from 104/3,537 (2.9%) patients. Seventy-six of 104 (73.1%) patients with K. oxytoca had no copathogens in their diarrheal stool samples. Twenty-four (31.6%) of 76 patients carried cytotoxin-producing strains, which were significantly associated with antibiotic therapy after hospital admission (50% versus 21.2%; P = 0.01). Health care-associated diarrhea was found in 44 (42%) of 104 patients with K. oxytoca, but there was no epidemiological linkage suggestive of a nosocomial outbreak, and PFGE showed a diverse pattern. None of the patients with cytotoxin-producing K. oxytoca developed antibiotic-associated hemorrhagic colitis, suggesting that K. oxytoca can cause a mild disease manifesting as uncomplicated antibiotic-associated diarrhea with winter seasonality. PMID:22357507

  2. Epidemiology of Klebsiella oxytoca-associated diarrhea detected by Simmons citrate agar supplemented with inositol, tryptophan, and bile salts.

    PubMed

    Cheng, Vincent C C; Yam, Wing-Cheong; Tsang, Lee-Lee; Yau, Miranda C Y; Siu, Gilman K H; Wong, Sally C Y; Chan, Jasper F W; To, Kelvin K W; Tse, Herman; Hung, Ivan F N; Tai, Josepha W M; Ho, Pak-Leung; Yuen, Kwok-Yung

    2012-05-01

    We studied the clinical and epidemiological characteristics of Klebsiella oxytoca-associated diarrhea in hospitalized patients in Hong Kong. Between 1 November 2009 and 30 April 2011, all inositol-fermenting colonies found on Simmons citrate agar supplemented with inositol, tryptophan, and bile salts (SCITB agar) used for the culturing of diarrheal stool samples were screened by a spot indole test for K. oxytoca. The overall sensitivity of SCITB agar plus the spot indole test (93.3%) for the detection of K. oxytoca in stool samples was superior to that of MacConkey agar (63.3%), while the specificities were 100% and 60.4%, respectively. The former achieved a 23-fold reduction in the workload and cost of subsequent standard biochemical identifications. Cytotoxin production and the clonality of K. oxytoca were determined by a cell culture cytotoxicity neutralization assay using HEp-2 cells and pulsed-field gel electrophoresis (PFGE), respectively. Of 5,581 stool samples from 3,537 patients, K. oxytoca was cultured from 117/5,581 (2.1%) stool samples from 104/3,537 (2.9%) patients. Seventy-six of 104 (73.1%) patients with K. oxytoca had no copathogens in their diarrheal stool samples. Twenty-four (31.6%) of 76 patients carried cytotoxin-producing strains, which were significantly associated with antibiotic therapy after hospital admission (50% versus 21.2%; P = 0.01). Health care-associated diarrhea was found in 44 (42%) of 104 patients with K. oxytoca, but there was no epidemiological linkage suggestive of a nosocomial outbreak, and PFGE showed a diverse pattern. None of the patients with cytotoxin-producing K. oxytoca developed antibiotic-associated hemorrhagic colitis, suggesting that K. oxytoca can cause a mild disease manifesting as uncomplicated antibiotic-associated diarrhea with winter seasonality. PMID:22357507

  3. Beyond Agar: Gel Substrates with Improved Optical Clarity and Drug Efficiency and Reduced Autofluorescence for Microbial Growth Experiments

    PubMed Central

    Jaeger, Philipp A.; McElfresh, Cameron; Wong, Lily R.

    2015-01-01

    Agar, a seaweed extract, has been the standard support matrix for microbial experiments for over a century. Recent developments in high-throughput genetic screens have created a need to reevaluate the suitability of agar for use as colony support, as modern robotic printing systems now routinely spot thousands of colonies within the area of a single microtiter plate. Identifying optimal biophysical, biochemical, and biological properties of the gel support matrix in these extreme experimental conditions is instrumental to achieving the best possible reproducibility and sensitivity. Here we systematically evaluate a range of gelling agents by using the yeast Saccharomyces cerevisiae as a model microbe. We find that carrageenan and Phytagel have superior optical clarity and reduced autofluorescence, crucial for high-resolution imaging and fluorescent reporter screens. Nutrient choice and use of refined Noble agar or pure agarose reduce the effective dose of numerous selective drugs by >50%, potentially enabling large cost savings in genetic screens. Using thousands of mutant yeast strains to compare colony growth between substrates, we found no evidence of significant growth or nutrient biases between gel substrates, indicating that researchers could freely pick and choose the optimal gel for their respective application and experimental condition. PMID:26070672

  4. Inhibition of Aspergillus flavus on agar media and brown rice cereal bars using cold atmospheric plasma treatment.

    PubMed

    Suhem, Kitiya; Matan, Narumol; Nisoa, Mudtorlep; Matan, Nirundorn

    2013-02-01

    This study aimed to optimize the operating parameters of cold atmospheric plasma treatment to inhibit the growth of Aspergillus flavus on agar media and brown rice cereal bars. The effects of argon plasma jet treatment on the growth of A. flavus on malt extract agar (MEA) at powers of 20 W and 40 W with exposure times at 5, 15 and 25 min were studied using response surface methodology (RSM) with a central composite face-centered (CCF) design. Multiple regression analysis indicated that plasma treatment at 40 W for 25 min is most effective for inhibiting growth of A. flavus on the agar medium. On brown rice cereal bars, plasma powered at 40 W for 20 min was capable of giving protection against A. flavus growth for up to 20 days under storage conditions of 25°C and 100% RH. These results demonstrated the potential of cold atmospheric plasma jet treatment to control mold growth on various food products. PMID:23279819

  5. Choline chloride based ionic liquid analogues as tool for the fabrication of agar films with improved mechanical properties.

    PubMed

    Sousa, Ana M M; Souza, Hiléia K S; Latona, Nicholas; Liu, Cheng-Kung; Gonçalves, Maria P; Liu, LinShu

    2014-10-13

    In the present paper, we test the suitability of ChCl/urea (DES-U) and ChCl/glycerol (DES-G) eutectic mixtures, each one prepared at 1:2 molar ratio, for the production of agar films. A three-step process is proposed: pre-solubilization of polymer in DES followed by compression-molding and subsequent drying. The mechanical properties, water resistance and microstructure of the films were evaluated at different polymer concentrations (i.e. 2-6%, w/w). DES-U showed by far, the best film forming ability. Agreeing with the diffusion and SEM data, films with the best mechanical properties were found at the lowest and highest agar concentrations (tensile strengths of 24.2-42 MPa and elongations of 15.4-38.9%). The water sorption and contact angle studies suggested increased hydrophilicity for the film containing the lowest concentration of agar. The use of choline chloride based ionic liquid analogues as solvent and plasticizer might be a promising tool for the development of new non-aqueous materials based on seaweed polysaccharides. PMID:25037344

  6. Irradiation of silver and agar/silver nanoparticles with argon, oxygen glow discharge plasma, and mercury lamp.

    PubMed

    Ahmad, Mahmoud M; Abdel-Wahab, Essam A; El-Maaref, A A; Rawway, Mohammed; Shaaban, Essam R

    2014-01-01

    The irradiation effect of argon, oxygen glow discharge plasma, and mercury lamp on silver and agar/silver nanoparticle samples is studied. The irradiation time dependence of the synthesized silver and agar/silver nanoparticle absorption spectra and their antibacterial effect are studied and compared. In the agar/silver nanoparticle sample, as the irradiation time of argon glow discharge plasma or mercury lamp increases, the peak intensity and the full width at half maximum, FWHM, of the surface plasmon resonance absorption band is increased, however a decrease of the peak intensity with oxygen glow plasma has been observed. In the silver nanoparticle sample, as the irradiation time of argon, oxygen glow discharge plasma or mercury lamp increases, the peak intensity of the surface plasmon resonance absorption band is increased, however, there is no significant change in the FWHM of the surface plasmon resonance absorption band. The SEM results for both samples showed nanoparticle formation with mean size about 50 nm and 40 nm respectively. Throughout the irradiation time with the argon, oxygen glow discharge plasma or mercury lamp, the antibacterial activity of several kinds of Gram-positive and Gram-negative bacteria has been examined. PMID:25184109

  7. Mechanical touch responses of Arabidopsis TCH1-3 mutant roots on inclined hard-agar surface

    NASA Astrophysics Data System (ADS)

    Zha, Guodong; Wang, Bochu; Liu, Junyu; Yan, Jie; Zhu, Liqing; Yang, Xingyan

    2016-01-01

    The gravity-induced mechanical touch stimulus can affect plant root architecture. Mechanical touch responses of plant roots are an important aspect of plant root growth and development. Previous studies have reported that Arabidopsis TCH1-3 genes are involved in mechano-related events, how-ever, the physiological functions of TCH1-3 genes in Arabidopsis root mechanoresponses remain unclear. In the present study, we applied an inclined hard agar plate method to produce mechanical touch stimulus, and provided evidence that altered mechanical environment could influence root growth. Furthermore, tch1-3 Arabidopsis mutants were investigated on inclined agar surfaces to explore the functions of TCH1-3 genes on Arabidopsis root mechanoresponses. The results showed that two tch2 mutants, cml24-2 and cml24-4, exhibited significantly reduced root length, biased skewing, and decreased density of lateral root. In addition, primary root length and density of lateral root of tch3 (cml12-2) was significantly decreased on inclined agar surfaces. This study indicates that the tch2 and tch3 mutants are hypersensitive to mechanical touch stimulus, and TCH2 (CML24-2 and CML24-4) and TCH3 (CML12-2) genes may participate in the mechanical touch response of Arabidopsis roots.

  8. Mutational analysis of flagellum-independent surface spreading of Serratia marcescens 274 on a low-agar medium.

    PubMed Central

    Matsuyama, T; Bhasin, A; Harshey, R M

    1995-01-01

    In a previous study (J. O'Rear, L. Alberti, and R. M. Harshey, J. Bacteriol. 174:6125-6137, 1992) we reported the isolation of several transposon mutants of Serratia marcescens 274 that were defective either in swarming alone or in both swimming and swarming motility. All the nonflagellate (Fla-) mutants, while defective in both types of motility, were able to spread rapidly on the surface of low-agar (0.35%) media. We show here that some of the swarming-defective mutants are defective in the production of serrawettin W1, an extracellular cyclic lipopeptide produced by S. marcescens 274. When combined with a Fla defect, the serrawettin (Swt) mutants are deficient in spreading on low-agar media. The spreading deficiency can be overcome by serrawettin supplied extracellularly. Introduction of Fla defects into chemotaxis mutants does not affect this mode of surface translocation. These results suggest that spreading may be a passive form of translocation. We also report that swarming defects in all mutants showing a Dps phenotype (able to swarm within the inoculated area but unable to move outward) in the earlier study can be overcome by changing the commercial source of agar. PMID:7860610

  9. Methylthymol blue in Fricke gels

    NASA Astrophysics Data System (ADS)

    Penev, K. I.; Mequanint, K.

    2015-01-01

    The initial trial of methylthymol blue (MTB) as a chelator for ferric iron in Fricke gel dosimeters, used for three-dimensional (3D) dosimetry in cancer radiotherapy, is reported. MTB is a structural analogue of the conventionally used xylenol orange (XO); however, the absorbance spectrum of the ferric-MTB complex is shifted to higher wavelengths, which should allow for lower amount of light scattering during gel scanning. In this study, two gelatin substrates, two sources of XO and one source of MTB have been compared. The MTB- containing gels exhibited similar dose response and diffusion coefficient to the XO-containing gels at their wavelengths of maximum absorption (620 and 585 nm, respectively). In addition, the MTB gels gave an excellent dose response at 633 nm, which is an important wavelength that is already used with other 3D dosimeters.

  10. Long-persistence blue phosphors

    NASA Technical Reports Server (NTRS)

    Yen, William M. (Inventor); Jia, Weiyi (Inventor); Lu, Lizhu (Inventor); Yuan, Huabiao (Inventor)

    2000-01-01

    This invention relates to phosphors including long-persistence blue phosphors. Phosphors of the invention are represented by the general formula: MO . mAl.sub.2 O.sub.3 :Eu.sup.2+,R.sup.3+ wherein m is a number ranging from about 1.6 to about 2.2, M is Sr or a combination of Sr with Ca and Ba or both, R.sup.3+ is a trivalent metal ion or trivalent Bi or a mixture of these trivalent ions, Eu.sup.2+ is present at a level up to about 5 mol % of M, and R.sup.3+ is present at a level up to about 5 mol % of M. Phosphors of this invention include powders, ceramics, single crystals and single crystal fibers. A method of manufacturing improved phosphors and a method of manufacturing single crystal phosphors are also provided.

  11. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    ERIC Educational Resources Information Center

    Liebl, Michael

    2010-01-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of

  12. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    ERIC Educational Resources Information Center

    Liebl, Michael

    2010-01-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of…

  13. Blue collection bag after ileal diversion.

    PubMed

    Hildreth, T A; Cass, A S

    1978-02-01

    Five children with ileal diversions have shown asymptomatic blue staining of the urine collection bags. A tryptophan derivative (indican) in the urine that oxidizes to indigo blue on exposure to air is thought to be the cause of this benign transient phenomenon. PMID:628994

  14. HOW TO MANAGE THE BLUE ORCHARD BEE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book explains how to raise blue orchard bee (Osmia lignaria) populations for orchard pollination. The book starts with an overview of orchard pollination requirements, followed by a detailed account on the natural history of the blue orchard bee. The following chapters describe how to build nes...

  15. Blue enhanced light sources: opportunities and risks

    NASA Astrophysics Data System (ADS)

    Lang, Dieter

    2012-03-01

    Natural daylight is characterized by high proportions of blue light. By proof of a third type of photoreceptor in the human eye which is only sensitive in this spectral region and by subsequent studies it has become obvious that these blue proportions are essential for human health and well being. In various studies beneficial effects of indoor lighting with higher blue spectral proportions have been proven. On the other hand with increasing use of light sources having enhanced blue light for indoor illumination questions are arising about potential health risks attributed to blue light. Especially LED are showing distinct emission characteristics in the blue. Recently the French agency for food, environmental and occupational health & safety ANSES have raised the question on health issues related to LED light sources and have claimed to avoid use of LED for lighting in schools. In this paper parameters which are relevant for potential health risks will be shown and their contribution to risk factors will quantitatively be discussed. It will be shown how to differentiate between photometric parameters for assessment of beneficial as well as hazardous effects. Guidelines will be discussed how blue enhanced light sources can be used in applications to optimally support human health and well being and simultaneously avoid any risks attributed to blue light by a proper design of lighting parameters. In the conclusion it will be shown that no inherent health risks are related to LED lighting with a proper lighting design.

  16. Isolation and detection of extended spectrum β-lactamase (ESBL)-producing enterobacteriaceae from meat using chromogenic agars and isothermal loop-mediated amplification (LAMP) assays.

    PubMed

    Anjum, M F; Lemma, F; Cork, D J; Meunier, D; Murphy, N; North, S E; Woodford, N; Haines, J; Randall, L P

    2013-12-01

    The aim of this work was to develop a molecular method using loop-mediated isothermal amplification (LAMP) for detection of extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae from meat, and to compare it with different isolation agars and microarrays. LAMP assays were developed for CTX-M groups 1, 2, and 9 and OXA-10-like genes. Chicken, lamb, beef, pork, and turkey samples were spiked with 10, 100, and 1,000 cfu/gram using 8 strains of ESBL-producing Enterobacteriaceae (CTX-M sequence types 1, 2, 3, 14, 15, OXA-11, SHV-2, TEM-52) +/- a mix of competitor organisms. Samples were enriched overnight in buffered peptone water (BPW) +/- antibacterials before plating to CHROMagar CTX, OXOID ESBL Brilliance agar, and MacConkey agar with 1 mg/L cefotaxime. Selected BPW broths were also tested using LAMP assays, microarrays and using cefpodoxime discs on agar. For isolation/detection of ESBL producers from beef, pork, lamb, and turkey spiked with 10 or 100 cfu/gram ESBL (natural flora only), all agars and the LAMP assays showed 100% sensitivity and specificity for ESBL spike strains. For chicken samples, both LAMP and chromogenic agars showed improved sensitivity and specificity for isolation of ESBLs compared with MacConkey agar, particularly with competitor bacteria added. In comparison, the cefpodoxime disc method and microarray showed reduced sensitivity. PMID:24329955

  17. [Comparison of ertapenem-EMB Agar with traditional methods for screening carbapenem-resistant Klebsiella pneumoniae from rectal swabs].

    PubMed

    Perçin, Duygu; Colakoğlu, Selcan; Durmaz, Süleyman; Ekincioğlu, Pınar

    2012-10-01

    Detection of rectal colonization with carbapenem-resistant Klebsiella pneumoniae (CRKP) is the most important step in the infection control protocols in order to prevent infections caused by CRKP which has an increasing incidence all over the world. In this study, it was aimed to compare the detection rate of 2 mg/L ertapenem EMB agar medium with the other methods recommended by various international guidelines. These methods include direct plate method using ertapenem disc, enrichment method in tryptic soy broth containing 2 mg/L ertapenem and the investigation of the predominant betalactamases in the colonized patients. The lowest inoculum detected by different methods was determined by using simulative challenge test prepared for this purpose. The ability to detect CRKP from rectal swabs was evaluated by using the clinical specimens of 801 patients. For all bacteria isolated, carbapenem susceptibility was evaluated by using E-test method, the presence of beta-lactamases was determined by using modified Hodge test (MHT), and the carbapenemase genes were investigated by using multiplex polymerase chain reaction (PCR). The lowest inoculum detected by ertapenem-EMB agar was 50 CFU/mL whereas the lowest inocula were 1 x 105 and 1 x 103, respectively by tryptic soy broth with ertapenem and direct plate method. No resistance gene were identified by PCR in 13 (39.4%) of 33 isolates, whereas blaOXA-48 was detected in 19 (95%) and blaIMP in 1 (5%) of 20 positive isolates. All of the positive strains were resistant to imipenem and ertapenem, while 2 (10%) strains were found to be susceptible to doripenem and meropenem. While MHT was negative in all strains which were negative for resistance genes, all resistance gene positive strains except one blaOXA-48 strain that was also sensitive to doripenem and meropenem, were found to be positive with MHT. According to the results of PCR, the sensitivities of the three methods were found to be 80%. The specificities, positive and negative predictive values were found to be 15.4%, 59% and 33.3% for ertapenem-EMB agar, 23%, 61.5% and 42.9% for broth with ertapenem and 61.5%, 76% and 66.6% for direct plate method, respectively. Average labor time of the methods (isolation + identification + sensitivity + MHT) was determined as 48 hours for ertapenem-EMB agar, whereas it was 96 hours for the other methods. In conclusion, since ertapenem- EMB agar method is a sensitive and rapid method, it can be used safely for the preliminary detection of CRKP without increasing the workload of the laboratory. PMID:23188568

  18. Featured Molecules: Ascorbic Acid and Methylene Blue

    NASA Astrophysics Data System (ADS)

    Coleman, William F.; Wildman, Randall J.

    2003-05-01

    The WebWare molecules of the month for May are featured in several articles in this issue. "Arsenic: Not So Evil After All?" discusses the pharmaceutical uses of methylene blue and its development as the first synthetic drug used against a specific disease. The JCE Classroom Activity "Out of the Blue" and the article "Greening the Blue Bottle" feature methylene blue and ascorbic acid as two key ingredients in the formulation of the blue bottle. You can also see a colorful example of these two molecules in action on the cover. "Sailing on the 'C': A Vitamin Titration with a Twist" describes an experiment to determine the vitamin C (ascorbic acid) content of citrus fruits and challenges students, as eighteenth-century sea captains, to decide the best fruit to take on a long voyage. Fully manipulable (Chime) versions of these and other molecules are available at Only@JCE Online.

  19. Characterization and optimization of hydrogen production by a salt water blue-green alga Oscillatoria sp. Miami BG 7. II - Use of immobilization for enhancement of hydrogen production

    NASA Technical Reports Server (NTRS)

    Phlips, E. J.; Mitsui, A.

    1986-01-01

    The technique of cellular immobilization was applied to the process of hydrogen photoproduction of nonheterocystous, filamentous marine blue-green alga, Oscillatoria sp. Miami BG 7. Immobilization with agar significantly improved the rate and longevity of hydrogen production, compared to free cell suspensions. Rates of H2 production in excess of 13 microliters H2 mg dry/wt h were observed and hydrogen production was sustained for three weeks. Immobilization also provided some stabilization to environmental variability and was adaptable to outdoor light conditions. In general, immobilization provides significant advantages for the production and maintenance of hydrogen photoproduction for this strain.

  20. Retinal Effects Of Blue Light Exposure

    NASA Astrophysics Data System (ADS)

    Ham, William T.; Mueller, Harold A.; Ruffolo, J. J.

    1980-10-01

    Recent research has shown that blue light exposure is an important factor in certain types of retinal injury. The mammalian ocular media transmits the spectral band 400-1400 nm to the retina. The short wavelengths (400-550 nm) produce a photochemical or actinic type of damage, while the longer wavelengths (550-1400 nm) produce thermal damage. Distinction between the two types of retinal damage are discussed briefly and the importance of the blue light effect for solar retinitis and eclipse blindness is emphasized. The significance of blue light retinal injury is summarized for various environmental and occupational exposures.

  1. Sleep deprivation and the postnatal blues.

    PubMed

    Wilkie, G; Shapiro, C M

    1992-05-01

    This prospective study of 63 women was designed to investigate the relationship between sleep disruption prior to the birth, during labour and in the early postpartum period and the subsequent development of the postnatal blues. The results from this preliminary study suggest that two factors: (a) a night-time labour; and (b) a history of sleep disruption in the latter stages of pregnancy, may have aetiological importance in the development of postnatal blues. There was little evidence from this study to suggest that sleep disruption on the nights following the birth, the third sleep factor investigated, had any impact on the expression of the blues. PMID:1593506

  2. Optimization of modified Middlebrook 7H11 agar for isolation of Mycobacterium bovis from raw milk cheese.

    PubMed

    Forgrave, R; Donaghy, J A; Fisher, A; Rowe, M T

    2014-10-01

    Reports have highlighted the absence of contemporary peer reviewed publications pertaining to Mycobacterium bovis culture from raw milk and cheese. By replicating traditional methods, cheese-making methodology and equipment were devised to produce Cheddar (n = 6) and Caerphilly (n = 3) artificially contaminated with M. bovis (three genotypes) under stringent laboratory-containment guidelines for handling hazardous microbiological material. Middlebrook 7H11, modified for M. bovis isolation, was assessed for capacity to enumerate M. bovis despite changing cheese microflora and prolonged M. bovis exposure to the cheese matrix using maturing cheese test portions (n = 63; up to 16 weeks). Malachite green (MG) containing media isolated M. bovis at significantly (P < 0·05) lower levels than unmodified Middlebrook 7H11 agar despite MG being a common adjunct of Middlebrook 7H11 agar modified for M. bovis growth. Subsequently, a selective MG-free Middlebrook 7H11 agar modified using haemolysed red cells and calf serum was demonstrated as the best performing (P < 0·05) medium for recovery of M. bovis from typical UK cheese types, Cheddar and Caerphilly. Significance and impact of the study: Following increased M. bovis infection of UK cattle, the risk posed to consumers from consumption of unpasteurized milk and dairy products has changed. Furthermore, published methods for the culture and molecular detection of M. bovis in raw milk products are limited. Cheese-making protocols and M. bovis culture media reported here provide tools for further investigation of M. bovis survival during all stages of cheese manufacture and could inform future assessment of the risk to consumers from M. bovis contamination of unpasteurized dairy products. PMID:24888395

  3. Performance of an Agar Dilution Method and a Vitek 2 Card for Detection of Inducible Clindamycin Resistance in Staphylococcus spp.?

    PubMed Central

    Lavalle, Christian; Rouleau, Danielle; Gaudreau, Christiane; Roger, Michel; Tsimiklis, Catherine; Locas, Marie-Claude; Gagnon, Simon; Delorme, Jocelyn; Labb, Annie-Claude

    2010-01-01

    The D-zone test detects inducible clindamycin resistance in Staphylococcus spp. Two other methods not described by the Clinical and Laboratory Standards Institute (CLSI) are available to test for this resistance mechanism: an agar dilution method and new Vitek 2 cards. This study evaluated the performance of both methods in detecting inducible clindamycin resistance. Nonduplicate clinical strains of Staphylococcus spp. (111 Staphylococcus aureus and 52 coagulase-negative staphylococcus strains), intermediate or resistant to erythromycin but susceptible to clindamycin, were obtained from three hospitals in Montreal, Quebec, Canada. Molecular analysis to detect resistance genes was conducted on all strains. A Mueller-Hinton agar containing 1 mg of erythromycin and 0.5 mg of clindamycin/liter was used for the dilution method, and two inocula were tested: 104 and 105 CFU per spot. Plates were read at 24 and 48 h. The Vitek 2 AST-P580 card was used according to the manufacturer's recommendations. The results were compared to those of the D-zone test. The D-zone test was positive in 134 of 163 (82%) strains. With the 104 CFU inoculum, the sensitivities were 84 and 99% at 24 and 48 h, respectively. The 105 CFU inoculum increased the sensitivities at 24 and 48 h to 91 and 100%, respectively. The specificity was 100% for the 104 CFU inoculum at 24 h and 97% for the other combinations. The sensitivity and specificity for the Vitek 2 card were 93 and 100%, respectively. The performance of both the agar dilution method and the Vitek 2 card was good, but these methods were not as sensitive as the D-zone test at 24 h. PMID:20164285

  4. Reliability of the agar based method to assess the production of degradative enzymes in clinical isolates of Candida albicans.

    PubMed

    Arantes, Paula Tamião; Sanitá, Paula Volpato; Santezi, Carolina; Barbeiro, Camila de Oliveira; Reina, Bárbara Donadon; Vergani, Carlos Eduardo; Dovigo, Lívia Nordi

    2016-03-01

    The aim of this study was to establish a reproducible protocol using the methodology of hyaline zones around the colonies on specific agar plates for phospholipase and proteinase production. This was an in vitro double-blind experiment, in which the dependent variables were the enzymatic activity measurements (Pz) for the production of phospholipase (Pz-ph) and the production of secreted aspartyl proteinases (Pz-sap). Three independent variables give rise to different measurement protocols. All measurements were carried out at two different moments by four examiners (E1, E2, E3, and E4). The minimum sample size was 30 Candida albicans clinical isolates. Specific agar plates for phospholipase and SAPs production were prepared according the literature. The intra-and inter-examiner reproducibility for each protocol was estimated using the Intraclass Correlation Coefficient (ICC) and its confidence interval (95% CI). Based on the results obtained for both phospholipase and SAPs, there appears to be no consensus on the protocol chosen for each particular examiner. Measuring the colonies in triplicate may be the main factor associated with the increase in measurement accuracy and should therefore take precedence over measuring only one colony. When only one examiner is responsible for taking measurements, a standard protocol should be put in place and the statistical calibration of this researcher should be done prior to data collection. However, if two or more researchers are involved in the assessment of agar plates, our results suggest that the protocols using software to undertake plate reading is preferred. PMID:26705836

  5. Comparison of NNA Agar Culture and Selective Broth Culture for Detection of Group B Streptococcal Colonization in Women

    PubMed Central

    Dunne, W. Michael; Holland-Staley, Carol A.

    1998-01-01

    In 1996, the Centers for Disease Control and Prevention recommended the use of a selective broth culture for the improved detection of genital tract or anorectal carriage of group B streptococci (GBS) in pregnant women. In order to verify this recommendation in our laboratory, we compared the sensitivity of Todd-Hewitt medium with gentamicin and nalidixic acid (SBM) with our current method of direct plating on blood agar medium containing neomycin and nalidixic acid (NNA). Five hundred consecutive cervicovaginal and anorectal specimens submitted for GBS culture were included in the study. Swabs were plated onto NNA and the swabs were immersed in SBM, followed by overnight incubation at 35°C. On the following day, the NNA plates were examined for colonies typical of GBS and the organisms were identified by the CAMP test or by latex agglutination. SBM cultures were subcultured onto blood agar and CNA agar plates, and the plates were reincubated for 24 h. Negative specimens from either medium were incubated for an additional 24 h and were examined again before finalization of the results. GBS were recovered from 78 specimens by both methods; from SBM only for 17 specimens (sensitivity, 86%) and from NNA only for 16 specimens (sensitivity, 85%). A moderate to heavy growth of Enterococcus faecalis was observed on plates containing NNA-positive, SBM-negative specimens. Competitive growth studies suggested that E. faecalis suppressed the growth potential of GBS in SBM. Our study suggests that direct plating on NNA, as a single method, is equivalent in sensitivity to SBM for the recovery of GBS, and the results are often available 24 h sooner. However, it appears that both direct plating and selective broth amplification techniques are required for the maximum level of identification of colonization with GBS in pregnant women. PMID:9666009

  6. Enumerating actinomycetes in compost bioaerosols at source—Use of soil compost agar to address plate 'masking'

    NASA Astrophysics Data System (ADS)

    Taha, M. P. M.; Drew, G. H.; Tamer Vestlund, A.; Aldred, D.; Longhurst, P. J.; Pollard, S. J. T.

    Actinomycetes are the dominant bacteria isolated from bioaerosols sampled at composting facilities. Here, a novel method for the isolation of actinomycetes is reported, overcoming masking of conventional agar plates, as well as reducing analysis time and costs. Repeatable and reliable actinomycetes growth was best achieved using a soil compost media at an incubation temperature of 44 °C and 7 days' incubation. The results are of particular value to waste management operators and their advisors undertaking regulatory risk assessments that support environmental approvals for compost facilities.

  7. High internal phase agar hydrogel dispersions in cocoa butter and chocolate as a route towards reducing fat content.

    PubMed

    Skelhon, Thomas S; Olsson, Patrik K A; Morgan, Adam R; Bon, Stefan A F

    2013-09-01

    Reducing the fat content of chocolate formulations is a major challenge for the confectionery industry. We report the suspension of aqueous microgel agar particles of up to 80% v/v within sunflower oil, cocoa butter, and ultimately chocolate. The optimised emulsification process involves a shear-cooling step. We demonstrate the versatility of our method when applied to white, milk, and dark chocolate formulations, whilst preserving the desired polymorph V of the cocoa butter matrix. In addition, we show that this technology can be used as a strategy to disperse alcoholic beverages into chocolate confectionery. PMID:23799607

  8. Enumeration of coagulase and thermonuclease-positive Staphylococcus spp. in raw milk and fresh soft cheese: an evaluation of Baird-Parker agar, Rabbit Plasma Fibrinogen agar and the Petrifilm Staph Express count system.

    PubMed

    Viçosa, Gabriela Nogueira; Moraes, Paula Mendonça; Yamazi, Anderson Keizo; Nero, Luís Augusto

    2010-06-01

    Staphylococcus spp. are microorganisms that are naturally present in milk and dairy products and are often associated with food-borne diseases outbreaks due to the ability of some strains to produce thermostable enterotoxins. This ability is usually associated with coagulase and thermonuclease production, characteristics that are considered in the microbiological analyses for the control of such microorganisms. The objective of this study was to evaluate the culture media and the methodologies used for the enumeration of coagulase and thermonuclease-positive Staphylococcus spp. in raw milk and fresh soft cheese. Samples of artificially contaminated milk (with coagulase-positive Staphylococcus reference strains) and samples of naturally contaminated raw milk and cheese were submitted for enumeration in Baird-Parker agar (BP), Rabbit Plasma Fibrinogen agar (RPFA) and in the Petrifilm Staph Express count system (STX). No significant differences (P > 0.05) were observed between the mean counts obtained in all of the evaluated culture media. RPFA and STX had good correlation indices between the total and typical colony counts as well as with coagulase and the thermonuclease-positive colony counts. Thus, there is a better association between coagulase and thermonuclease production to typical colony morphology developed on these culture media, leading to more accurate and reliable results than with BP, which demonstrated lower correlation indices between these counts. PMID:20417392

  9. Blue Ribbon Commission Tour of Hanford Site

    ScienceCinema

    Paul Saueressig

    2010-09-01

    The Blue Ribbon Commission on America's Nuclear Future toured the Department of Energy's Hanford Site on July 14, 2010. Commission members, invited guests, and members of the public visited facilities that store high-level, radioactive waste.

  10. Fingermarks detection by eosin-blue dye.

    PubMed

    Sodhi, G S; Kaur, J

    2001-01-01

    Eosin-blue (I) dye, along with a phase transfer catalyst, has been used to detect latent fingerprints on a wide range of surfaces, including paper, glass, steel, lamination sheets, polythene, plastic and bakelite. PMID:11056271

  11. Studies on plasma processing of blue dust

    NASA Astrophysics Data System (ADS)

    Samal, S. K.; P, Sindhoora L.; Mishra, S. C.; Mishra, B.

    2015-02-01

    Plasma smelting was carried out using blue dust and petroleum coke mixtures for five different compositions. By altering percentage of reductant and type of plasma forming gas, recovery rate and degree of metallization were calculated in order to examine the extent of reduction of blue dust. The products were characterized by XRD and optical microscopy techniques. The results of these investigations exhibited that highest degree of metallization and recovery rate of about 98% and 86% respectively, were achieved for nitrogen plasma smelted products.

  12. Si-based blue light emitting diode

    NASA Astrophysics Data System (ADS)

    Namavar, Fereydoon

    1994-05-01

    Phase 1 results demonstrated for the first time a strong, stable blue-green emission from C-implanted red-emitting porous silicon. The objective of Phase 1 was to obtain blue-green emission from porous Si structure either by increasing the bandgap of the substrate by growth of Si-C random alloys prior to forming nanostructures with quantum confined properties, or by increasing the confinement energy of red-emitting Si nanostructures. Porous structures fabricated from group 4 alloys epitaxially grown by chemical vapor deposition (CVD) resulted in an enhancement in light emission of about one order of magnitude after incorporation of a very small amount of carbon in the epitaxial grown films. Strong blue-green light emission was observed by the naked eye from C-implanted and annealed porous Si. Using AlGaAs as a reference, we observed that the intensity of blue-green emission was one order of magnitude higher than that of the original red-emitting porous Si. Catholuminescence measurements of our samples performed at the University of Colorado show blue emission at 1.80 eV and 2.80 eV. Fourier transform infrared (FTIR) spectra of a blue-green emitting porous structure shows an IR absorption line identical to that of SiC and electron diffraction studies clearly show reflections corresponding to beta-SiC. Phase 1 results indicate that blue-green light is from SiC nanostructures with quantum confined properties. This material may be used to fabricate blue light-emitting Si-based devices which can be easily integrated into Si technology.

  13. MitoBlue: A Nontoxic and Photostable Blue-Emitting Dye That Selectively Labels Functional Mitochondria

    PubMed Central

    2014-01-01

    We report the discovery of a fluorogenic dye, N1,N3-di(2-aminidonaphthalen-6-yl) propane-1,3-diamine, MitoBlue, which selectively stains functional mitochondria while displaying low toxicity, bright blue emission, and high resistance to photobleaching. Additionally, we show that a biotin-labeled MitoBlue derivative can be used as a handle for the delivery of streptavidin-tagged species to the mitochondria. PMID:25325672

  14. Blue space geographies: Enabling health in place.

    PubMed

    Foley, Ronan; Kistemann, Thomas

    2015-09-01

    Drawing from research on therapeutic landscapes and relationships between environment, health and wellbeing, we propose the idea of 'healthy blue space' as an important new development Complementing research on healthy green space, blue space is defined as; 'health-enabling places and spaces, where water is at the centre of a range of environments with identifiable potential for the promotion of human wellbeing'. Using theoretical ideas from emotional and relational geographies and critical understandings of salutogenesis, the value of blue space to health and wellbeing is recognised and evaluated. Six individual papers from five different countries consider how health can be enabled in mixed blue space settings. Four sub-themes; embodiment, inter-subjectivity, activity and meaning, document multiple experiences within a range of healthy blue spaces. Finally, we suggest a considerable research agenda - theoretical, methodological and applied - for future work within different forms of blue space. All are suggested as having public health policy relevance in social and public space. PMID:26238330

  15. Blue-phase liquid crystal droplets

    PubMed Central

    Martínez-González, José A.; Zhou, Ye; Rahimi, Mohammad; Bukusoglu, Emre; Abbott, Nicholas L.; de Pablo, Juan J.

    2015-01-01

    Blue phases of liquid crystals represent unique ordered states of matter in which arrays of defects are organized into striking patterns. Most studies of blue phases to date have focused on bulk properties. In this work, we present a systematic study of blue phases confined into spherical droplets. It is found that, in addition to the so-called blue phases I and II, several new morphologies arise under confinement, with a complexity that increases with the chirality of the medium and with a nature that can be altered by surface anchoring. Through a combination of simulations and experiments, it is also found that one can control the wavelength at which blue-phase droplets absorb light by manipulating either their size or the strength of the anchoring, thereby providing a liquid–state analog of nanoparticles, where dimensions are used to control absorbance or emission. The results presented in this work also suggest that there are conditions where confinement increases the range of stability of blue phases, thereby providing intriguing prospects for applications. PMID:26460039

  16. Comparison of spiral gradient endpoint and agar dilution methods for susceptibility testing of anaerobic bacteria: a multilaboratory collaborative evaluation.

    PubMed

    Wexler, H M; Molitoris, E; Murray, P R; Washington, J; Zabransky, R J; Edelstein, P H; Finegold, S M

    1996-01-01

    A multilaboratory collaborative study was carried out to assess the utility of the spiral gradient endpoint (SGE) method for the determination of the antimicrobial susceptibilities of anaerobes and to evaluate the equivalence of the MICs obtained by the SGE method with those obtained by the reference agar dilution method of the National Committee for Clinical Laboratory Standards. The standard deviation of the MIC obtained by the SGE method for the five participating laboratories was +/- 0.26 of a twofold dilution, whereas it was +/- 1 twofold dilution by the reference method. The interlaboratory reproducibility of the results for two control strains tested with imipenem, chloramphenicol, and metronidazole indicated that 96% of the measurements fell within +/- 1 twofold dilution of the mode. The equivalence of the SGE method with the agar dilution method was assessed with a wide variety of anaerobic organisms. The MICs by both methods were within 1 doubling dilution in 93% of the measurements (n = 1,074). Discrepancies generally occurred with those organism-drug combinations that resulted in tailing endpoints (Fusobacterium nucleatum, 86% agreement) or in cases of light growth (Peptostreptococcus spp., 86% agreement). PMID:8748295

  17. Malt-yeast extract-sucrose agar, a suitable medium for enumeration and isolation of fungi from silage.

    PubMed Central

    Skaar, I; Stenwig, H

    1996-01-01

    A general medium named malt-yeast extract-sucrose agar (MYSA) containing oxgall was designed. The medium was intended for the enumeration and isolation of molds and yeasts in routine examinations of animal feed stuffs. In this study MYSA was tested as a general medium for mycological examination of silage. The medium was compared with dichloran-rose bengal medium (DRBC) in an examination of more than 500 specimens of big bale grass silage. Selected characteristics of known fungal species commonly isolated from feeds were examined after growth on MYSA and DRBC and on malt extract agar, used as a noninhibitory control medium. MYSA suppressed bacterial growth, without affecting the growth of fungi common in feeds. The fungi growing on MYSA were easily recognized, and the medium seemed to slow radial growth of fungal colonies, which permitted, easy counting. The number of species found was higher on MYSA than on DRBC. When we compared MYSA with DRBC for mycological examination of grass silage samples, MYSA was found to be the medium of choice. PMID:8837416

  18. An evaluation of the CHO/HGPRT mutation assay involving suspension cultures and soft agar cloning: results for 33 chemicals.

    PubMed

    Oberly, T J; Rexroat, M A; Bewsey, B J; Richardson, K K; Michaelis, K C

    1990-01-01

    The Chinese hamster ovary cell assay (CHO), which measures forward mutation of the HGPRT locus, is used in several laboratories for the detection of mutagens. A procedure involving treatment of CHO cells in suspension culture and mutant selection in soft agar cloning has been developed (Oberly TJ, Bewsey BJ, Probst GS (1987): Mutat Res 182:99-111). In order to evaluate the effectiveness of these modifications, 33 chemicals representing six chemical classes were tested, and the results were compared to findings obtained in other tests for genotoxicity at Lilly Research Laboratories (LRL). A positive response was obtained with 21 chemicals, all of which are recognized mutagens. Of the 12 compounds that produced negative results, 4 were considered to be mutagens and/or carcinogens. Twelve of the compounds mentioned in this report have been previously tested in the CHO/HGPRT assay by other laboratories, and the results showed strong agreement between laboratories. These findings support the conclusion that the use of suspension cultures and soft agar cloning in the CHO assay provides a sensitive test for the identification of mutagens and is a viable alternative to the traditional monolayer procedure of O'Neill et al. (O'Neill JP, Couch DB, Machanoff R, San Sebastian JR, Brimer PA, Hsie AW (1977): Mutat Res 45:103-109). PMID:2253605

  19. In vitro fermentation and prebiotic potential of novel low molecular weight polysaccharides derived from agar and alginate seaweeds.

    PubMed

    Ramnani, Priya; Chitarrari, Roberto; Tuohy, Kieran; Grant, John; Hotchkiss, Sarah; Philp, Kevin; Campbell, Ross; Gill, Chris; Rowland, Ian

    2012-02-01

    Fermentation properties and prebiotic potential of novel low molecular weight polysaccharides (LMWPs) derived from agar and alginate bearing seaweeds was investigated. Ten LMWPs were supplemented to pH, temperature controlled anaerobic batch cultures inoculated with human feces from three donors, in triplicate. Microbiota changes were monitored using Fluorescent in-situ hybridization and short chain fatty acids, the fermentation end products were analysed using gas chromatography. Of the ten LMWPs tested, Gelidium seaweed CC2253 of molecular weight 64.64 KDa showed a significant increase in bifidobacterial populations from log(10) 8.06 at 0 h to log(10) 8.55 at 24 h (p = 0.018). For total bacterial populations, alginate powder CC2238 produced a significant increase from log(10) 9.01 at 0 h to log(10) 9.58 at 24 h (p = 0.032). No changes were observed in the other bacterial groups tested viz. Bacteroides, Lactobacilli/Enterococci, Eubacterium rectale/Clostridium coccoides and Clostridium histolyticum. The polysaccharides also showed significant increases in total SCFA production, particularly acetic and propionic acids, indicating that they were readily fermented. In conclusion, some LMWPs derived from agar and alginate bearing seaweeds were fermented by gut bacteria and exhibited potential to be used a novel source of prebiotics. PMID:21924371

  20. Agar-Silica-Gel Heating Phantom May Be Suitable for Long-Term Quality Assurance of MRgHIFU

    NASA Astrophysics Data System (ADS)

    Partanen, Ari

    2009-04-01

    In MRgHIFU, the purpose of frequent quality assurance is to detect changes in system performance to prevent adverse effects during treatments. Due to high ultrasound intensities in MRgHIFU, it is essential to assure that the procedure is safe and efficacious and that image-based guidance of the treatment is reliable. We aimed to develop a guideline for MRgHIFU QA by acquiring MR temperature maps during ultrasonic heating of an agar-silica-gel phantom over a four month-period using three separate MRgHIFU uterine leiomyoma treatment systems. From this data, the stability of the maximum temperature elevation, the targeting accuracy, and the dimensions of the heated volume were analyzed. Additionally, we studied the sensitivity of these parameters to reveal hypothetical decrease in HIFU performance. After calibration, the mean targeting offsets of the heated volume were observed to be less than 2 mm in the three orthogonal directions. The measured maximum temperature elevation and the length and the width of the heated volume remained consistent throughout the four-month period. Furthermore, it was found that the parameters under investigation were sensitive to reveal the decreased HIFU performance. We conclude that an agar-silica -based phantom is suitable for targeting accuracy and heating properties QA of MRgHIFU system even in long-term use. Moreover, this simple QA method may be used to reveal small changes in HIFU performance assuring consistent functionality and safety of the MRgHIFU system.

  1. Highly efficient synthesis of exopolysaccharides by Lactobacillus curvatus DPPMA10 during growth in hydrolyzed wheat flour agar.

    PubMed

    Minervini, F; De Angelis, M; Surico, R F; Di Cagno, R; Gänzle, M; Gobbetti, M

    2010-06-30

    The aim of this study was to optimize the production of exopolysaccharides (EPS) by sourdough Lactobacillus curvatus DPPMA10 for industrial application. The effects of pH, temperature, planktonic or attached cells and of some food matrices as substrates were studied. Wheat flour hydrolysate (WFH), reconstituted skimmed milk (RSM) and whey milk were supplemented with fresh yeast extract, mineral salts, and/or molasses. Non-controlled pH, starting from 5.6 to 3.5, was the optimal condition for L. curvatus DPPMA10. Temperature of 30 degrees C was also found to be optimal. Solid surfaces (agar culture media) stimulated attached bacteria to synthesize EPS (> or = of two-fold, P<0.05) with respect to planktonic cells (broth media). The highest production of EPS (ca. 46-50 g/kg of wet medium) was found during growth as attached cells in WFH agar supplemented with glucose, sucrose or molasses, mineral salts and fresh yeast extract at 30 degrees C for 48 h. As shown by high-performance liquid chromatography analysis, glucose was the only hydrolysis end-product for EPS synthesized during 48 h of incubation. The EPS synthesized by L. curvatus DPPMA10 improved the quality of bread and was utilized as carbon course by intestinal strains of lactobacilli and bifidobacteria. The synthesis of EPS by L. curvatus DPPMA10 under the conditions of this study may open new perspectives for their industrial applications. PMID:20398955

  2. Dependence of ablative ability of high-intensity focused ultrasound cavitation-based histotripsy on mechanical properties of agar.

    PubMed

    Xu, Jin; Bigelow, Timothy A; Davis, Gabriel; Avendano, Alex; Shrotriya, Pranav; Bergler, Kevin; Hu, Zhong

    2014-12-01

    Cavitation-based histotripsy uses high-intensity focused ultrasound at low duty factor to create bubble clouds inside tissue to liquefy a region, and provides better fidelity to planned lesion coordinates and the ability to perform real-time monitoring. The goal of this study was to identify the most important mechanical properties for predicting lesion dimensions, among these three: Young's modulus, bending strength, and fracture toughness. Lesions were generated inside tissue-mimicking agar, and correlations were examined between the mechanical properties and the lesion dimensions, quantified by lesion volume and by the width and length of the equivalent bubble cluster. Histotripsy was applied to agar samples with varied properties. A cuboid of 4.5 mm width (lateral to focal plane) and 6 mm depth (along beam axis) was scanned in a raster pattern with respective step sizes of 0.75 and 3 mm. The exposure at each treatment location was either 15, 30, or 60 s. Results showed that only Young's modulus influenced histotripsy's ablative ability and was significantly correlated with lesion volume and bubble cluster dimensions. The other two properties had negligible effects on lesion formation. Also, exposure time differentially affected the width and depth of the bubble cluster volume. PMID:25480051

  3. Determination of in vitro synergy for dual antimicrobial therapy against resistant Neisseria gonorrhoeae using Etest and agar dilution.

    PubMed

    Wind, Carolien M; de Vries, Henry J C; van Dam, Alje P

    2015-03-01

    In response to antimicrobial resistance of Neisseria gonorrhoeae to last-resort extended-spectrum cephalosporins, combination therapy of azithromycin+ceftriaxone is now recommended. Dual therapy can be effective to treat monoresistant strains as well as multidrug-resistant strains, preferably employing the effect of in vitro synergy. As reports on in vitro synergy of azithromycin+ceftriaxone in N. gonorrhoeae are conflicting, in this study an evaluation of this combination was performed using a cross-wise Etest method and agar dilution. Synergy was defined as a fractional inhibitory concentration index (FICI) of ≤0.5. To identify other dual treatment options for gonorrhoea, in vitro synergy was evaluated for 65 dual antimicrobial combinations using Etest. Azithromycin, cefixime, ceftriaxone, colistin, ertapenem, fosfomycin, gentamicin, minocycline, moxifloxacin, rifampicin, spectinomycin and tigecycline were screened for synergy in all possible combinations. No synergy or antagonism was found for any of the 65 combinations. The geometric mean FICI ranged from 0.82 to 2.00. The mean FICI of azithromycin+ceftriaxone was 1.18 (Etest) and 0.55 (agar dilution). The difference between both methods did not result in a difference in interpretation of synergy. Ceftriaxone-resistant strain F89 was tested in all combinations and no synergy was found for any of them. Most importantly, the ceftriaxone minimum inhibitory concentration of F89 was not decreased below the breakpoint with any concentration of azithromycin. PMID:25532741

  4. 49 CFR 218.23 - Blue signal display.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Blue signal display. 218.23 Section 218.23..., DEPARTMENT OF TRANSPORTATION RAILROAD OPERATING PRACTICES Blue Signal Protection of Workers 218.23 Blue signal display. (a) Blue signals displayed in accordance with 218.25, 218.27, or 218.29 signify...

  5. Methemoglobinemia induced by methylene blue pertubation during laparoscopy.

    PubMed

    Bilgin, H; Ozcan, B; Bilgin, T

    1998-05-01

    Methylene blue is used to check tubal patency during laparoscopy. A case of methemoglobinemia which was induced by methylene blue is presented. Methemoglobinemia is usually treated with methylene blue; however, in patients with glucose-6-phosphate dehydrogenase deficiency, methylene blue can induce methemoglobinemia. PMID:9605379

  6. Comparison of Alcian Blue, Trypan Blue, and Toluidine Blue for Visualization of the Primo Vascular System Floating in Lymph Ducts

    PubMed Central

    Kim, Da-Un; Han, Jae Won; Jung, Sharon Jiyoon; Lee, Seung Hwan; Cha, Richard; Chang, Byung-Soo; Soh, Kwang-Sup

    2015-01-01

    The primo vascular system (PVS), floating in lymph ducts, was too transparent to be observed by using a stereomicroscope. It was only detectable with the aid of staining dyes, for instance, Alcian blue, which was injected into the lymph nodes. Some dyes were absorbed preferentially by the PVS than the lymph wall. It remains a standing problem to know what dyes are absorbed better by the PVS than the lymph walls. Such information would be useful to unravel the biochemical properties of the PVS that are badly in need for obtaining large amount of PVS specimens. In the current work we tried two other familiar dyes which were used in PVS research before. We found that Trypan blue and toluidine blue did not visualize the PVS. Trypan blue was cleared by the natural washing. Toluidine blue did not stain the PVS, but it did leave stained spots in the lymph wall and its surrounding tissues, and it leaked out of the lymph wall to stain surrounding connective tissues. These completely different behaviors of the three dyes were found for the first time in the current work and provide valuable information to elucidate the mechanism through which some special dyes stained the PVS preferentially compared to the lymphatic wall. PMID:26379749

  7. Variations on the "Blue-Bottle" Demonstration Using Food Items That Contain FD&C Blue #1

    ERIC Educational Resources Information Center

    Staiger, Felicia A.; Peterson, Joshua P.; Campbell, Dean J.

    2015-01-01

    Erioglaucine dye (FD&C Blue #1) can be used instead of methylene blue in the classic "blue-bottle" demonstration. Food items containing FD&C Blue #1 and reducing species such as sugars can therefore be used at the heart of this demonstration, which simply requires the addition of strong base such as sodium hydroxide lye.

  8. Use of big data by Blue Cross and Blue Shield of North Carolina.

    PubMed

    Helm-Murtagh, Susan C

    2014-01-01

    The health care industry is grappling with the challenges of working with and analyzing large, complex, diverse data sets. Blue Cross and Blue Shield of North Carolina provides several promising examples of how big data can be used to reduce the cost of care, to predict and manage health risks, and to improve clinical outcomes. PMID:24830494

  9. Room-Temperature Liquid Crystal Blue Phases

    NASA Astrophysics Data System (ADS)

    Taushanoff, Stefanie; van Le, Khoa; Twieg, Robert; Jakli, Antal

    2009-03-01

    The ``blue phases'' of a highly chiral liquid crystal are defect-studded structures of double-twist cylinders that are laced together. The three phases, BPI*, BPII* and BPIII* differ only in the packing of the double-twist cylinders. Until recently, blue phases were of limited practical use because they appeared for only a very narrow temperature range. Mixtures that show BPI* and BPII* phases for wide temperature ranges at or around room temperature are now available [1]. Relatively wide temperature BPIII (the blue fog) phase so far was available only at very high temperatures [2]. Here we present mixtures with room-temperature wide range BPIII* phase and compare the ability of chiral dopants to form the different blue phases in a base nematic mixture. PDLC films cast with blue-phase material are also examined.[3pt] [1] H. Coles and M. Pivnenko, Nature 2005 436-18 997-1000 [0pt] [2] C. V. Yelamaggad, I. S. Shashikala, G. Liao, D.S. Shankar Rao, S. K. Prasad , Q. Li A. Jakli, Chem. Mater Comm, 2006, 18, 6100-6102

  10. "Blue and seven phenomena" among Japanese students.

    PubMed

    Saito, M

    1999-10-01

    To investigate color and number preferences in Japan, 586 university undergraduates (239 men and 347 women; M age = 20.9 yr.) were asked to name a color (Question 1), to name their preferred color (Question 2), and to name their preferred number between zero and nine (Question 3). The results showed that Japanese students chose blue (33.5%) or red (26.0%) when asked to name a color but that red was not chosen as frequently as blue as a preferred color (red: 11.1%, blue: 37.1%). Sex differences were found on both Questions 1 and 2 by chi-squared test. Black was chosen more by men, while pink was selected more by women. 22.5% subjects also selected the number seven, supporting Simon's observation of the "blue-seven phenomenon." The reasons given for the choice showed that seven was "a lucky number" and "represented happiness" among Japanese students. Four colors (blue, red, white, and black) accounted for 76.8% and 65.1% of responses to Questions 1 and 2, respectively, and odd numbers 68.4% for Question 3. PMID:10597589

  11. [Analysis of bactericidal material generated by electrical devices advertising bactericidal ability against bacteria on the agar gel plates].

    PubMed

    Nishimura, Hidekazu

    2012-11-01

    Several Japanese companies sell electrical devices advertised as effective in inactivating viruses and killing bacteria by releasing special materials, e.g., Plasmacluster ions, Nanoe particle and minus ions, into the air. These companies claim that their devices killed bacteria on plates in their own experiments. We tested device effectiveness using the same experiments from the Plasmacluster ioniser SHARP Co., Japan, the Nanoe generator Panasonic Co., Japan, and the Vion KING JIM Co., Japan, to test their advertising claims. Bactericidal ability on agar plate was tested, using Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus cereus, and Enterococcus faecalis as follows: the medium containing a certain amount of each bacterium was put onto an agar plate and smeared. Plates were kept in a closed chamber (inner volume 14.4 m3) or a glove box (inner volume 0.2 m), with one of the devices run for 2 hours. Plates not exposed to any device were used as controls. Each plate was retrieved and put in an incubator to count the number of bacterial colonies formed on the plate. There was no significant difference in the number of colonies on plates exposed to devices compared to control, in the number for all devices, or in all bacteria tested in experiments in the 14.4 m3 chamber. These results strongly suggest that these devices have almost no bactericidal effect, at least in space exceeding this volume. Colony formation was suppressed in the glove box in all devices and in all bacteria tested except P. aeruginosa, although the degree of suppression differed among experiments. The colony formation suppression mechanism was analyzed, and indicated that:colony formation did not change even after the removal of Plasmacluster ions, Nanoe particles, or negative ions from the air, while colony formation was decreased drastically by the removal of ozone from space, which was revealed to be generated inevitably during device operation. These results strongly suggest that the bactericidal effect seen only on the agar plate in narrow space was explained by ozone released in space as a by-product, not by special materials as advertising claimed. It is thus important to analyze the effect of special materials such as those done in this study and to suggest the involvement of ozone as the true cause, as have been done in this study, in evaluating bactericidal effect or viral inactivation as advertised by these companies. PMID:23367847

  12. Blue laser devices for optical data storage

    NASA Astrophysics Data System (ADS)

    Lenth, Wilfried; Kozlovsky, William J.; Risk, William P.

    1991-07-01

    A number of different techniques have been used for nonlinear frequency upconversion of near-infrared semiconductor diode lasers to blue wavelengths. Intracavity frequency doubling of a diode-laser-pumped 946- nm Nd:YAG laser resulted in generation of 9.5 mW of blue 473-nm power. A special electronic servo technique was devised to lock the output frequency of a single-mode GaAlAs diode laser to a monolithic KNbO3 resonator. Using this approach, 54 mW of 428-nm output were obtained with an electrical-to-optical conversion efficiency of approximately equals 12%. The use of nonlinear waveguide devices for frequency doubling of near- infrared diode lasers is promising for the development of miniaturized, low-cost blue laser sources.

  13. Higher recovery rate of microorganisms from cerebrospinal fluid samples by the BACTEC culture system in comparison with agar culture.

    PubMed

    Calderaro, Adriana; Martinelli, Monica; Montecchini, Sara; Motta, Federica; Covan, Silvia; Larini, Sandra; Medici, Maria Cristina; Arcangeletti, Maria Cristina; Chezzi, Carlo; De Conto, Flora

    2016-04-01

    The aim of this study was to assess the diagnostic value of the BACTEC FX blood culture (BC) system as compared to the agar culture (AC) of cerebrospinal fluid samples (CSF), evaluating the recovery rate and the time to detection of microorganisms in a 3.5-year period. From December 2011 to May 2015, 1326 CSF samples (694 patients) were submitted to both AC and BC. Among the 150 positive samples (96 patients), 165 microorganisms were detected: 81 by both the protocols, 77 by BC alone, and 7 by AC alone, demonstrating a higher detection rate of BC (95.8%) than AC (53.3%). Although BC presents some disadvantages, it is able to improve the yield of clinically significant microorganisms, and it could potentially reduce the reporting time as compared to AC. The results obtained highlighted the necessity of a combined approach for the successful detection of central nervous system microbial infections. PMID:26867963

  14. Germination of non-irradiated and gamma-irradiated fungal spores on water agar and natural soil.

    PubMed

    El-Abyad, M S; Ismail, I K

    1979-01-01

    Germination and germ-tube lengths of non-irradiated and gamma-irradiated spores of eight soil fungi were studied on water agar and on natural soil. Non-irradiated spores showed variable degrees of sensitivity to the fungistatic factor in natural soil. Lower doses of gamma-irradiation (5 K rad) produced stimulus to germination and germ-tube lengths without losing the fungistatic properties of the fungi concerned. Germination at the rest of treatments (100 and 500 K rad) showed significant inhibition, the magnitude of which is a function of the dose used. Germ-tube lengths did not follow the same pattern. The results are discussed in view of the nutritional theory of fungistasis. PMID:396932

  15. The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds.

    PubMed

    Pusnik, Mascha; Imeri, Minire; Deppierraz, Grégoire; Bruinink, Arie; Zinn, Manfred

    2016-01-01

    A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds, and this at higher sensitivity and in a quantitative way. PMID:26861591

  16. Biomimetic synthesis of hollow calcium carbonate with the existence of the agar matrix and bovine serum albumin.

    PubMed

    Feng, Jianhua; Wu, Gang; Qing, Chengsong

    2016-01-01

    Proteins play important roles in the process of biomineralization. Vaterite and calcite have been synthesized by the reaction of Na2CO3 and CaCl2 in the bovine serum albumin (BSA) and agar system. The samples have been characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The shape of CaCO3 crystal has been analyzed by scanning electronic microscopy (SEM). The results show that calcite is a single product in the absence of BSA, but the product is a mixture of calcite and vaterite in the presence of BSA. The spheral shell of CaCO3 crystal was obtained when the concentration of BSA increased to 9.0mg/mL. PMID:26478327

  17. Preliminary identification of beta-hemolytic streptococci in throat swab cultures with a commercial blood agar slide (streptocult).

    PubMed Central

    Christensen, P; Danielsson, D; Hovelius, B; Kjellander, J

    1982-01-01

    A commercial blood agar slide (Streptocult, Orion Diagnostica) was used for preliminary identification of beta-hemolytic streptococci of groups A, C, and G in throat swab specimens. The sensitivity of the test was 93.6% and the specificity was 94.7%, as judged from 580 specimens. A model is suggested for routine processing of throat swab specimens, involving inoculation and reading of the slide in general practice and transport of positive or inconclusive slides to a bacteriology laboratory for isolation and serological grouping of beta-hemolytic streptococci. The model combines preliminary detection of beta-hemolytic streptococci within 24 h with the reliability of serological groupings, and should reduce the volume of specimens sent to the laboratory considerably. Images PMID:7050155

  18. The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds

    PubMed Central

    Pusnik, Mascha; Imeri, Minire; Deppierraz, Grégoire; Bruinink, Arie; Zinn, Manfred

    2016-01-01

    A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds, and this at higher sensitivity and in a quantitative way. PMID:26861591

  19. Some observations on the three-dimensional growth of L5178Y cell colonies in soft agar culture.

    NASA Technical Reports Server (NTRS)

    Dalen, H.; Burki, H. J.

    1971-01-01

    The three-dimensional organization of spherical colonies formed by L5178Y cells grown in soft agar cultures was investigated by light and scanning electron microscopy. Visible colonies were formed after 7 days of incubation and increased in size for more than 2 weeks. At this time the colonies contained a central core of necrotic cells surrounded by an outer shell of normal-looking cells in loose contact with each other. Cross sectional radioautographs revealed that tritiated precursors were incorporated only into those cells in the ?viable cell' shell and not in the necrotic center of the colony. It is pointed out that increased knowledge of the factors leading to this type of three-dimensional organization is of particular interest, since it is similar to the conditions found in certain types of solid tumors (Thomlinson and Gray, 1955).

  20. Identification of non-mutans streptococci organisms in dental plaques recovering on mitis-salivarius bacitracin agar medium.

    PubMed

    Yoo, So Young; Kim, Pyung Sik; Hwang, Ho-Keel; Lim, Seong-Hoon; Kim, Kwang-Won; Choe, Son-Jin; Min, Byung-Moo; Kook, Joong-Ki

    2005-04-01

    The objective of this study was to both isolate and identify non-mutans streptococci organisms (non-MSO) from dental plaques recovered on mitis-salivarius sucrose bacitracin agar (MSB) plates. The dental plaque samples, which had been collected from 63 human subjects, were diluted and plated on MSB. The bacteria growing on the MSB plates were then identified with biochemical tests, as well as with 16S rDNA cloning and sequencing techniques. Our data indicated that bacteria from 30 subjects had been recovered on the MSB plates. Among the 21 typical colonies selected from the 30 subjects, 12 colonies, derived from 10 subjects, were identified as non-MSO. These 12 colonies were determined to be Streptococcus anginosus (8 colonies), S. sanguinis (1 colony), and Pantoea agglomerans (3 colonies). These results strongly suggest that a new selective medium will be required for the reliable isolation of mutans streptococci. PMID:15880098

  1. Effects of extracellular matrix proteins on macrophage differentiation, growth, and function: comparison of liquid and agar culture systems

    NASA Technical Reports Server (NTRS)

    Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Both spaceflight and skeletal unloading suppress the haematopoietic differentiation of macrophages (Sonnenfeld et al., Aviat. Space Environ. Med., 61:648-653, 1990; Armstrong et al., J. Appl. Physiol., 75:2734-2739, 1993). The mechanism behind this reduction in haematopoiesis has yet to be elucidated. However, changes in bone marrow extracellular matrix (ECM) may be involved. To further understand the role of ECM products in macrophage differentiation, we have performed experiments evaluating the effects of fibronectin, laminin, collagen type I, and collagen type IV on macrophage development and function. Bone marrow-derived macrophages cultured on four different ECM substrates in liquid culture medium showed less growth than those cultured on plastic. Significant morphological differences were seen on each of the substrates used. Phenotypically and functionally, as measured by class II major histocompatibility molecule (MHCII) expression, MAC-2 expression, and the secretion of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), these macrophages were similar. In contrast, bone marrow-derived macrophages cultured in suspension, using agar, showed no difference in growth when exposed to ECM proteins. However, IL-6 and TNF-alpha secretion was affected by fibronectin, laminin, collagen type I, and collagen type IV in a concentration-dependent manner. We conclude that the ECM products fibronectin, laminin, collagen type I, and collagen type IV have profound effects on macrophage development and function. Additionally, we suggest that an ECM-supplemented agar culture system provides an environment more analogous to in vivo bone marrow than does a traditional liquid culture system.

  2. Evaluation of a New Selective Chromogenic Agar Medium for Detection of Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae▿

    PubMed Central

    Glupczynski, Youri; Berhin, Catherine; Bauraing, Caroline; Bogaerts, Pierre

    2007-01-01

    A novel chromogenic agar medium (ESBL-Bx; bioMérieux, Marcy l'Etoile, France) was compared to MacConkey agar supplemented with 2 mg ceftazidime/liter (MCKC) for the selective isolation and presumptive identification of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae directly from clinical samples. Of a total of 644 clinical specimens (including 551 fecal samples), 496 yielded no growth and 148 yielded growth on one or both media. Overall, 44 ESBL-producing Enterobacteriaceae strains (Escherichia coli [n = 17], Enterobacter aerogenes [n = 17], Klebsiella spp. [n = 5], and Citrobacter freundii [n = 5]) were isolated from 37 specimens by a combination of both methods after 18 to 24 h of incubation. The sensitivities were 97.7 and 84.1% for ESBL-Bx and MCKC, respectively, with 43 ESBL-positive strains isolated as colored colonies from 36 specimens on ESBL-Bx versus 37 ESBL-positive organisms isolated from 32 specimens on MCKC. The specificities by specimens were 89 and 91% for ESBL-Bx and MCKC, respectively. On either one of the two media, natural AmpC-hyperproducing Enterobacter spp. (n = 25) and Citrobacter spp. (n = 14) were the most common false positives as well as non-ESBL-producing Klebsiella oxytoca (n = 18) on ESBL-Bx and Morganella morganii (n = 10) on MCKC. We conclude that ESBL-Bx is a sensitive and specific medium for the isolation of ESBL-producing Enterobacteriaceae from clinical samples. The main advantages of ESBL-Bx over MCKC reside in its chromogenic character and its sensitivity and selectivity, which enabled the recovery and presumptive identification of most ESBL-producing Enterobacteriaceae within 24 h and reduced by 27% the need for unnecessary identification and confirmation of ESBL testing when disregarding all colorless colonies growing on this medium. PMID:17182756

  3. Comparison of automated BAX PCR and standard culture methods for detection of Listeria monocytogenes in blue Crabmeat (Callinectus sapidus) and blue crab processing plants.

    PubMed

    Pagadala, Sivaranjani; Parveen, Salina; Schwarz, Jurgen G; Rippen, Thomas; Luchansky, John B

    2011-11-01

    This study compared the automated BAX PCR with the standard culture method (SCM) to detect Listeria monocytogenes in blue crab processing plants. Raw crabs, crabmeat, and environmental sponge samples were collected monthly from seven processing plants during the plant operating season, May through November 2006. For detection of L. monocytogenes in raw crabs and crabmeat, enrichment was performed in Listeria enrichment broth, whereas for environmental samples, demi-Fraser broth was used, and then plating on both Oxford agar and L. monocytogenes plating medium was done. Enriched samples were also analyzed by BAX PCR. A total of 960 samples were examined; 59 were positive by BAX PCR and 43 by SCM. Overall, there was no significant difference (P ? 0.05) between the methods for detecting the presence of L. monocytogenes in samples collected from crab processing plants. Twenty-two and 18 raw crab samples were positive for L. monocytogenes by SCM and BAX PCR, respectively. Twenty and 32 environmental samples were positive for L. monocytogenes by SCM and BAX PCR, respectively, whereas only one and nine finished products were positive. The sensitivities of BAX PCR for detecting L. monocytogenes in raw crabs, crabmeat, and environmental samples were 59.1, 100, and 60%, respectively. The results of this study indicate that BAX PCR is as sensitive as SCM for detecting L. monocytogenes in crabmeat, but more sensitive than SCM for detecting this bacterium in raw crabs and environmental samples. PMID:22054196

  4. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    NASA Astrophysics Data System (ADS)

    Liebl, Michael

    2010-05-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available.2-5 Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of classroom demonstrations have been described for showing the effects.6-11 This paper describes how these demonstrations can be enhanced by using a spectrometer to measure the preferential scattering of the shorter wavelength light.

  5. Eastward migration of blue-winged teal

    USGS Publications Warehouse

    Sharp, B.

    1972-01-01

    Of 3,789 recoveries of blue-winged teal (Anas discors) banded prior to the hunting season in the prairie pothole region, 183 (4.8 percent) were recovered, due east in New England, Ontario, Quebec, and the Maritime Provinces during the subsequent hunting season. Of 19 recoveries looked at in detail, all were banded as either hatching-year (flying young) or local (flightless young) birds. A blue-winged teal banded in Minnesota in September was retrapped in October in South Carolina, before being shot later that month in Colombia, South America.

  6. Complexation between carrageenan and methylene blue for sensor design

    NASA Astrophysics Data System (ADS)

    Ling, Yew Pei; Heng, Lee Yook

    2013-11-01

    Theoretical studies on the methylene blue (MB)-carrageenans complexation at solution and solid states have been carried out via ultraviolet spectrophotoscopy and reflectometry methods. The equilibrium constant (Ka) of the MBcarrageenans complexation follows the order of Iota > Lambda > Kappa carrageenans, which indicated Iota-carrageenan forms a stable complex. MB-carrageenan complexation reaction showed decrease in Ka value from 210.71 ppm-1 to 114.57 ppm-1 when the reaction temperature increased from 298 K to 323 K. Le Chatelier's principle and mass action law explained that the MB-carrageenan complexation was an exothermic reaction (ΔH=-18.54 kJmol-1) that release heat. Thus MB-carrageenan complex was less stable at high temperature and tend to dissociate into free MB and carrageenan molecules. It was also supported by the van't Hoff equation. The reaction is a spontaneous process (ΔG=-13.23 kJmol-1) where the randomness of the molecules reduced (ΔS=-17.83 Jmol-1K-1) due to complexation. Besides, linear regression of the concentration and absorption of the MB-carrageenan reaction obeys the Beer Lambert law, which elucidated that the complexation process was not affected by any concentration dependent factors such as aggregation and self-quenching. Moreover, linear Benesi Hilderbrend plot revealed that the interaction between MB and carrageenan was a reversible and stoichiometric reaction with 1:1 ratio. However, the molar extinction coefficient (ɛ) and molar adsorption coefficient (μa) of the MB-carrageenan complex were lower compared to free MB, described that the complex was less adsorptive. The sensor constructed based on these theoretical investigations showed response behavior that was similar with solution test as both have attraction for carrageenans in the sequence of Iota-, Lambda-, Kappa- carrageenans. Likewise, carrageenan sensor was more selective towards Iota-carrageenan than to Lambda- and Kappa-carrageenans, and no response observed when tested with agar, alginate and glucose. Therefore the sensor is able to detect carrageenans specifically and offers rapid detection without the need of sample pretreatment when compared to conventional methods.

  7. Enumeration of sublethally injured Escherichia coli O157:H7 ATCC 43895 and Escherichia coli strain B-41560 using selective agar overlays versus commercial methods.

    PubMed

    Smith, Amanda R; Ellison, Alysha L; Robinson, Amanda L; Drake, Maryanne; McDowell, Susan A; Mitchell, James K; Gerard, Patrick D; Heckler, Rachel A; McKillip, John L

    2013-04-01

    Quality control procedures during food processing may involve direct inoculation of food samples onto appropriate selective media for subsequent enumeration. However, sublethally injured bacteria often fail to grow, enabling them to evade detection and intervention measures and ultimately threaten the health of consumers. This study compares traditional selective and nonselective agar-based overlays versus two commercial systems (Petrifilm and Easygel) for recovery of injured E. coli B-41560 and O157:H7 strains. Bacteria were propagated in tryptic soy broth (TSB), ground beef slurry, and infant milk formula to a density of 10(6) to 10(8) CFU/ml and then were stressed for 6 min either in lactic acid (pH 4.5) or heat shocked for 3 min at 60°C. Samples were pour plated in basal layers of either tryptic soy agar (TSA), sorbitol MacConkey agar (SMAC), or violet red bile agar (VRB) and were resuscitated for 4 h prior to addition of agar overlays. Other stressed bacteria were plated directly onto Petrifilm and Easygel. Results indicate that selective and nonselective agar overlays recovered significantly higher numbers (greater than 1 log) of acid- and heat-injured E. coli O157:H7 from TSB, ground beef, and infant milk formula compared with direct plating onto selective media, Petrifilm, or Easygel, while no significant differences among these media combinations were observed for stressed E. coli B-41560. Nonstressed bacteria from TSB and ground beef were also recovered at densities significantly higher in nonselective TSA-TSA and in VRB-VRB and SMAC-SMAC compared with Petrifilm and Easygel. These data underscore the need to implement food safety measures that address sublethally injured pathogens such as E. coli O157:H7 in order to avoid underestimation of true densities for target pathogens. PMID:23575132

  8. Photodynamic antimicrobial chemotherapy on Streptococcus mutans using curcumin and toluidine blue activated by a novel LED device.

    PubMed

    Paschoal, Marco Aurelio; Lin, Meng; Santos-Pinto, Lourdes; Duarte, Simone

    2015-02-01

    Photodynamic antimicrobial chemotherapy (PACT) is an antimicrobial approach that uses photosensitizers (PS) in combination with light sources at specific wavelengths aiming the production of reactive oxygen species. The long illumination time necessary to active PS is a challenge in PACT. Thus, this study investigated the antimicrobial effect of a novel single source of light-emitting diode (LED) light that covers the entire spectrum of visible light beyond interchangeable probes at high power intensity. Blue and red LED probes were used into different exposure times to active different concentrations of curcumin (C) and toluidine blue (T) on planktonic suspensions of Streptococcus mutans UA 159 (S. mutans). S. mutans were standardized and submitted to (1) PACT treatment at three concentrations of C and T exposure at three radiant exposures of a blue LED (BL) (C+BL+) and a red LED (RL) (T+RL+), (2) C (C+BL-) or T alone (T+RL-), (3) both LED lights (C-BL+ and T-RL+), and (4) neither PS nor LED illumination (control group: C-BL- and T-RL-). Aliquots of the suspensions were diluted and cultured on blood agar plates. The number of colony-forming units was calculated after 48 h. The groups submitted to PACT presented a lethal photokilling rate to all PS concentrations at tested dosimetries. The comparison to control group when PS and LED lights used alone demonstrated no decrease in the number of viable bacterial counts. The novel LED device in combination with curcumin and toluidine blue promoted an effective photoinactivation of S. mutans suspensions at ultrashort light illumination times. PMID:24249357

  9. Oral Actinomyces Isolates Forming Red Colonies on Brain Heart Blood Agar Can Be Unambiguously Classified as A. odontolyticus by Macroscopic Examination

    PubMed Central

    Kaetzke, Annette; Körner, Henrike; Kneist, Susanne; Eschrich, Klaus

    2003-01-01

    The accurate classification of oral Actinomyces isolates as one species is difficult. Out of 18 Actinomyces isolates forming red colonies on brain heart blood agar, 12 could be straightforwardly assigned as Actinomyces odontolyticus by biochemical, morphological, and chemotaxonomic characteristics. For the remaining six isolates, the results of the different identification methods were inconsistent. By sequencing a 16S ribosomal DNA fragment by a rapid mass spectrometric method, all isolates could be identified unambiguously as A. odontolyticus. This result proves the importance of red colony pigmentation on brain heart blood agar together with the characteristic cell morphology for unequivocal assignment of oral Actinomyces isolates to the species A. odontolyticus. PMID:12904382

  10. Visualising DNA in Classrooms Using Nile Blue

    ERIC Educational Resources Information Center

    Milne, Christine; Roche, Scott; McKay, David

    2008-01-01

    Giving students the opportunity to extract, manipulate and visualise DNA molecules enhances a constructivist approach to learning about modern techniques in biology and biotechnology Visualisation usually requires agarose gel electrophoresis and staining. In this article, we report on an alternative DNA stain, Nile Blue A, that may be used in the…

  11. Blue beetle-killed pine park

    Stripped bark from a dead pine tree reveals the tell-tale blue streaks of a mountain pine beetle attack. Mountain pine beetle outbreaks can result in the loss of millions of pine trees throughout western North America. The beetles lay eggs and develop in the bark of mountain trees, especially lodge...

  12. Authoritarianism and the Blue-Collar Student.

    ERIC Educational Resources Information Center

    Carnahan, Robert E.; Cancro, John Patrick

    The relationship between students' family background (blue-collar versus nonblue-collar) and authoritarianism, as measured by the California F-Scale, was studied. In addition, strategies that might be used to assist faculty in teaching students with authoritarian tendencies are suggested. The sample consisted of 222 students attending a two-year…

  13. Blue whales respond to anthropogenic noise.

    PubMed

    Melcón, Mariana L; Cummins, Amanda J; Kerosky, Sara M; Roche, Lauren K; Wiggins, Sean M; Hildebrand, John A

    2012-01-01

    Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood. PMID:22393434

  14. Blue LED irradiation to hydration of skin

    NASA Astrophysics Data System (ADS)

    Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

    2015-06-01

    Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

  15. 21 CFR 133.106 - Blue cheese.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... having the same physical and chemical properties. It is characterized by the presence of bluish-green... ingredients. (i) Blue or green color in an amount to neutralize the natural yellow color of the curd. (ii... or cuts in consumer-sized packages or to the surface of the bulk cheese during curing. (v)...

  16. T's and Blues. Specialized Information Service.

    ERIC Educational Resources Information Center

    Do It Now Foundation, Phoenix, AZ.

    This compilation of journal articles provides basic information on abuse of Talwin, a mild prescription painkiller (T's), and Pyribenzamine, a nonprescription antihistimine (Blues). These two drugs, taken in combination, produce an effect similar to that produced by heroin. Stories from "Drug Survival News,""Emergency Medicine," and "FDA Consumer"

  17. Heparin sensing: Blue-chip binding

    NASA Astrophysics Data System (ADS)

    Shriver, Zachary; Sasisekharan, Ram

    2013-08-01

    Heparin is an anionic polysaccharide that has tremendous clinical importance as an anticoagulant. Several dyes have been developed that can detect heparin, and the latest example -- named Mallard Blue -- has now been shown to have excellent sensing properties under biologically relevant conditions.

  18. Blue Whales Respond to Anthropogenic Noise

    PubMed Central

    Melcón, Mariana L.; Cummins, Amanda J.; Kerosky, Sara M.; Roche, Lauren K.; Wiggins, Sean M.; Hildebrand, John A.

    2012-01-01

    Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood. PMID:22393434

  19. A Code Blue Answer to Training

    ERIC Educational Resources Information Center

    Huneycutt, Richy; Callahan, Barbara; Welch, Alexis

    2008-01-01

    Code Blue addresses the capacity challenges in healthcare training. This pilot, grant funded project, focuses on a holistic approach to selecting and educating career ready and capable students and training them to be confident and competent healthcare workers. Lessons learned from this project will be assessed and reviewed for replication.

  20. Great Blue Heron and Great Egret

    A great blue heron and great egret in the parking lot by the Big Cypress Bend boardwalk at Fakahatchee Strand State Preserve. The heron is enjoying a fish dinner thanks to the hunting skills of the egret. While the egret had initially held a fish in it's beak, the heron's squabbling caused the...

  1. [The dangers of blue light: True story!].

    PubMed

    Renard, G; Leid, J

    2016-05-01

    The dangers of the blue light are the object of numerous publications, for both the scientific community and the general public. The new prolific development of light sources emitting potentially toxic blue light (415-455nm) ranges from LED (Light Emitting Diodes) lamps for interior lighting to television screens, computers, digital tablets and smartphones using OLED (Organic Light Emitting Diode) or AMOLED (Active-Matrix Organic Light Emitting Diode) technology. First we will review some technical terms and the main characteristics of light perceived by the human eye. Then we will discuss scientific proof of the toxicity of blue light to the eye, which may cause cataract or macular degeneration. Analysis of the light spectra of several light sources, from natural light to LED lamps, will allow us to specify even better the dangers related to each light source. LED lamps, whether used as components for interior lighting or screens, are of concern if they are used for extended viewing times and at short distance. While we can protect ourselves from natural blue light by wearing colored glasses which filter out, on both front and back surfaces, the toxic wavelengths, it is more difficult to protect oneself from LED lamps in internal lighting, the use of which should be restricted to "white warmth" lamps (2700K). As far as OLED or AMOLED screens are concerned, the only effective protection consists of using them occasionally and only for a short period of time. PMID:27039979

  2. The Blues/Rock Group Biography

    ERIC Educational Resources Information Center

    Lindsay, Brian

    1974-01-01

    Blues and rock groups provide vivid topics for research and writing at the secondary level. Instructional suggestions acknowledge the abundance of both fact and flack noting the need for discrimination between the two by both teacher and student in the research and evaluation processes. (JH)

  3. Practices of Blue Ribbon Catholic Schools, 2001.

    ERIC Educational Resources Information Center

    Kealey, Robert J., Comp.

    For almost 20 years, the U.S. Department of Education has invited schools to seek the Blue Ribbon School Award. A large number of Catholic schools have received this award. For this publication, the Department of Elementary Schools Executive Committee requested principals of awarded schools to write a short article on an exemplary school program…

  4. Quirks of dye nomenclature. 3. Trypan blue.

    PubMed

    Cooksey, C J

    2014-11-01

    Trypan blue is colorant from the 19(th) century that has an association with Africa as a chemotherapeutic agent against protozoan (Trypanosomal) infections, which cause sleeping sickness. The dye still is used for staining biopsies, living cells and organisms, and it also has been used as a colorant for textiles. PMID:24867494

  5. KEPONE: TOXICITY AND BIOACCUMULATION IN BLUE CRABS

    EPA Science Inventory

    Two long-term studies were conducted to determine toxicity, uptake and duration of Kepone in blue crabs (Callinectes sapidus). In the first, Kepone was administered to crabs in seawater 0.03 or 0.3 micrograms Kepone/l or food (eastern oyster, Crassostrea virginica, containing 0.2...

  6. Blue-noise halftoning for hexagonal grids.

    PubMed

    Lau, Daniel L; Ulichney, Robert

    2006-05-01

    In this paper, we closely scrutinize the spatial and spectral properties of aperiodic halftoning schemes on rectangular and hexagonal sampling grids. Traditionally, hexagonal sampling grids have been shunned due to their inability to preserve the high-frequency components of blue-noise dither patterns at gray-levels near one-half, but as will be shown, only through the introduction of diagonal correlations between dots can even rectangular sampling grids preserve these frequencies. And by allowing the sampling grid to constrain the placement of dots, a particular algorithm may introduce visual artifacts just as disturbing as excess energy below the principal frequency. If, instead, the algorithm maintains radial symmetry by introducing a minimum degree of clustering, then that algorithm can maintain its grid defiance illusion fundamental to the spirit of the blue-noise model. As such, this paper shows that hexagonal grids are preferrable because they can support gray-levels near one-half with less required clustering of minority pixels and a higher principal frequency. Along with a thorough Fourier analysis of blue-noise dither patterns on both rectangular and hexagonal sampling grids, this paper also demonstrates the construction of a blue-noise dither array for hexagonal grids. PMID:16671307

  7. Visualising DNA in Classrooms Using Nile Blue

    ERIC Educational Resources Information Center

    Milne, Christine; Roche, Scott; McKay, David

    2008-01-01

    Giving students the opportunity to extract, manipulate and visualise DNA molecules enhances a constructivist approach to learning about modern techniques in biology and biotechnology Visualisation usually requires agarose gel electrophoresis and staining. In this article, we report on an alternative DNA stain, Nile Blue A, that may be used in the

  8. T's and Blues. Specialized Information Service.

    ERIC Educational Resources Information Center

    Do It Now Foundation, Phoenix, AZ.

    This compilation of journal articles provides basic information on abuse of Talwin, a mild prescription painkiller (T's), and Pyribenzamine, a nonprescription antihistimine (Blues). These two drugs, taken in combination, produce an effect similar to that produced by heroin. Stories from "Drug Survival News,""Emergency Medicine," and "FDA Consumer"…

  9. Blue nano titania made in diffusion flames.

    PubMed

    Teleki, Alexandra; Pratsinis, Sotiris E

    2009-05-21

    Blue titanium suboxide nanoparticles (including Magneli phases) were formed directly without any post-processing or addition of dopants by combustion of titanium-tetra-isopropoxide (TTIP) vapor at atmospheric pressure. Particle size, phase composition, rutile and anatase crystal sizes as well as the blue coloration were controlled by rapid quenching of the flame with a critical flow nozzle placed at various heights above the burner. The particles showed a broad absorption in the near-infrared region and retained their blue color upon storage in ambient atmosphere. A high concentration of paramagnetic Ti3+ centres was found in the substoichiometric particles by electron paramagnetic resonance (EPR) spectroscopy. Furthermore particles with controlled band gap energy from 3.2 to 3.6 eV were made by controlling the burner-nozzle-distance from 10 to 1 cm, respectively. The color robustness and extent of suboxidation could be further enhanced by co-oxidation of TTIP with hexamethyldisiloxane in the flame resulting in SiO2-coated titanium suboxide particles. The process is cost-effective and green while the particles produced can replace traditional blue colored, cobalt-containing pigments. PMID:19421486

  10. Geographical Study of American Blues Culture

    ERIC Educational Resources Information Center

    Strait, John B.

    2010-01-01

    Music is not often utilized in teaching geography, despite the fact that many scholars orient their research around analyzing both the historical and spatial dimensions of musical expression. This article reports on the use of a teaching module that utilizes blues culture as a lens to understand the geographical history of the United States. The…

  11. Avoiding the Negative: Blue Jeans Baseball

    ERIC Educational Resources Information Center

    Maggard, Bob

    1978-01-01

    Blue Jeans Baseball, for eight- to twelve-year old children, is based on the concept that everyone plays. No coaches are allowed; everyone bats once per inning; defensive players rotate positions. These and other rules reduce the emphasis on competition and increase the emphasis on skill development. (MJB)

  12. 7 CFR 1217.2 - Blue Ribbon Commission or BRC.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING..., PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Softwood Lumber Research, Promotion, Consumer Education, and Industry Information Order Definitions § 1217.2 Blue Ribbon Commission or BRC. Blue...

  13. Comparison of eight different agars for the recovery of clinically relevant non-O157 Shiga toxin-producing Escherichia coli from baby spinach, cilantro, alfalfa sprouts and raw milk.

    PubMed

    Kase, Julie A; Maounounen-Laasri, Anna; Son, Insook; Lin, Andrew; Hammack, Thomas S

    2015-04-01

    The FDA Bacteriological Analytical Manual (BAM) Chapter 4a recommends several agars for isolating non-O157 Shiga toxin-producing Escherichia coli (STEC); not all have been thoroughly tested for recovering STECs from food. Using E. coli strains representing ten clinically relevant O serogroups (O26, O45, O91, O103, O104, O111, O113, O121, O128, O145) in artificially-contaminated fresh produce--bagged baby spinach, alfalfa sprouts, cilantro, and raw milk--we evaluated the performance of 8 different agars. Performance was highly dependent upon strain used and the presence of inhibitors, but not necessarily dependent on food matrix. Tellurite resistant-negative strains, O91:-, O103:H6, O104:H21, O113:H21, and O128, grew poorly on CHROMagar STEC, Rainbow agar O157, and a modified Rainbow O157 (mRB) agar. Although adding washed sheep's blood to CHROMagar STEC and mRB agars improved overall performance; however, this also reversed the inhibition of non-target bacteria provided by original formulations. Variable colony coloration made selecting colonies from Rainbow agar O157 and mRB agars difficult. Study results support a strategy using inclusive agars (e.g. L-EMB, SHIBAM) in combination with selective agars (R & F E. coli O157:H7, CHROMagar STEC) to allow for recovery of the most STECs while increasing the probability of recovering STEC in high bacterial count matrices. PMID:25475297

  14. Developing the urban blue: Comparative health responses to blue and green urban open spaces in Germany.

    PubMed

    Völker, Sebastian; Kistemann, Thomas

    2015-09-01

    Recently, new perspectives upon healthy urban open spaces propose that open spaces can be regarded as urban green or blue spaces. However, there has so far been very little research into blue environments and their benefits for mental well-being. Our article focuses on the effects of water in cities, "urban blue" (as compared to "urban green"), on human health and well-being. To assess the mental well-being of visitors, we conducted qualitative semi-standardised interviews (n=113), asking which differences in well-being occur when visiting urban green and blue spaces in high-density areas of the inner city in Dusseldorf and Cologne, Germany. Although we found many similarities, some health-enhancing effects for users turned out to be prominent for urban blue in the four conceptual therapeutic landscape dimensions: experienced, symbolic, social and activity space. These effects include enhanced contemplation, emotional bonding, participation, and physical activity. The results suggest that urban blue as a health-promoting factor needs more detailed and accurate determination and examination of its general and local health-enhancing effects. PMID:25475835

  15. Strain-rate and temperature dependent material properties of Agar and Gellan Gum used in biomedical applications.

    PubMed

    Schiavi, Alessandro; Cuccaro, Rugiada; Troia, Adriano

    2016-01-01

    Agar and Gellan Gum are biocompatible polymers extensively used in several fields of tissue engineering research (e.g. tissue replacement, tissue support, tissue mimicking), due to their mechanical behaviour effectively representative of actual biological tissues. Since mechanical properties of artificial tissues are related to biocompatibility and functionality of medical implants and significantly influence adhesion, growth and differentiation of cells in tissue-engineering scaffolds, an accurate characterization of Young׳s modulus and relaxation time processes is needed. In this study, the strain-rate and temperature dependent material properties of Agarose and one among the numerous kind of Gellan Gum commercially available, known as Phytagel(®), have been investigated. Nine hydrogel samples have been realized with different mechanical properties: the first one Agar-based as a reference material, the further eight samples Gellan Gum based in which the effect of dispersed solid particles like kieselguhr and SiC, as enhancing mechanical properties factors, have been investigated as a function of concentration. Stress-strain has been investigated in compression and relaxation time has been evaluated by means of the Kohlrausch-Williams-Watts time decay function. Mechanical properties have been measured as a function of temperature between 20 °C and 35 °C and at different strain rates, from ~10(-3)s(-1) and ~10(-2)s(-1) (or deformation rate from ~0.01 mms(-1) to ~0.1 mms(-1)). From experimental data, the combined temperature and strain-rate dependence of hydrogels Young׳s modulus is determined on the basis of a constitutive model. In addition to a dependence of Young׳s modulus on temperature, a remarkable influence of strain-rate has been observed, especially in the sample containing solid particles; in same ranges of temperature and strain-rate, also relaxation time variations have been monitored in order to identify a possible dependence of damping properties on temperature and strain-rate. The result is the impossibility to determine univocally mechanical properties of studied biomaterials without a proper definition of boundary conditions at which they have been obtained. PMID:26318572

  16. Preparation, Optimization, and Screening of the Effect of Processing Variables on Agar Nanospheres Loaded with Bupropion HCl by a D-Optimal Design

    PubMed Central

    Varshosaz, Jaleh; Zaki, Mohammad Reza; Minaiyan, Mohsen; Banoozadeh, Jaafar

    2015-01-01

    Bupropion is an atypical antidepressant drug. Fluctuating in its serum levels following oral administration of immediate release dosage forms leads to occasional seizure. The aim of the present work was designing of sustained release bupropion HCl nanospheres suited for pulmonary delivery. Agar nanospheres were prepared by transferring the w/o emulsion to solid in oil (s/o) suspension. Calcium chloride was used as cross-linking agent and hydroxypropyl β-cyclodextrin (HPβCD) was used as permeability enhancer. A response surface D-optimal design was used for optimization of nanospheres. Independent factors included in the design were calcium chloride percent, speed of homogenization, agar percent, and HPβCD percent. Optimum condition was predicted to be achieved when the calcium chloride was set at 7.19%, homogenization speed at 8500 rpm, agar content at 2%, and HPβCD at 0.12%. The optimized nanoparticles showed particle size of 587 nm, zeta potential of −30.9 mV, drug loading efficiency of 38.6%, and release efficiency of 51% until 5 h. The nanospheres showed high degree of bioadhesiveness. D-optimal response surface method is a satisfactory design to optimize the fabrication of bupropion HCl loaded agar nanospheres and these nanospheres can be successively exploited to deliver bupropion in a controlled manner for a sufficiently extended period. PMID:26090423

  17. Use of agar diffusion assay to measure bactericidal activity of alkaline salts of fatty acids against bacteria associated with poultry processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The agar diffusion assay was used to examine antibacterial activity of alkaline salts of caproic, caprylic, capric, lauric, and myristic acids. A 0.5M concentration of each fatty acid was dissolved in 1.0 M potassium hydroxide (KOH), and pH of the mixtures was adjusted to 10.5 with citric acid. Solu...

  18. A comparison of a new centrifuge sugar flotation technique with the agar method for the extraction of immature Culicoides (Diptera: Ceratopogonidae) life stages from salt marsh soils.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two sampling techniques, agar extraction (AE) and centrifuge sugar flotation extraction (CSFE) were compared to determine their relative efficacy to recover immature stages of Culicoides spp from salt marsh substrates. Three types of samples (seeded with known numbers of larvae, homogenized field s...

  19. Maya blue: a computational and spectroscopic study.

    PubMed

    Giustetto, Roberto; Llabrés I Xamena, Francesc X; Ricchiardi, Gabriele; Bordiga, Silvia; Damin, Alessandro; Gobetto, Roberto; Chierotti, Michele R

    2005-10-20

    Maya Blue pigment, used in pre-Colombian America by the ancient Mayas, is a complex between the clay palygorskite and the indigo dye. The pigment can be manufactured by mixing palygorskite and indigo and heating to T > 120 degrees C. The most quoted hypothesis states that the dye molecules enter the microchannels which permeate the clay structure, thus creating a stable complex. Maya Blue shows a remarkable chemical stability, presumably caused by interactions formed between indigo and clay surfaces. This work aims at studying the nature of these interactions by means of computational and spectroscopic techniques. The encapsulation of indigo inside the clay framework was tested by means of molecular modeling techniques. The calculation of the reaction energies confirmed that the formation of the clay-organic complex can occur only if palygorskite is heated at temperatures well above the water desorption step, when the release of water is entropically favored. H-bonds between the clay framework and the indigo were detected by means of spectroscopic methods. FTIR spectroscopy on outgassed palygorskite and freshly synthesized Maya Blue samples showed that the presence of indigo modifies the spectroscopic features of both structural and zeolitic water, although no clear bands of the dye groups could be observed, presumably due to its very low concentration. The positions and intensities of delta(H2O) and nu(H2O) modes showed that part of the structural water molecules interact via a hydrogen bond with the C=O or N-H groups of indigo. Micro-Raman spectra clearly evidenced the presence of indigo both in original and in freshly synthesized Maya Blue. The nu(C=O) symmetric mode of Maya Blue red-shifts with respect to pure indigo, as the result of the formation of H-bonds with the nearest clay structural water. Ab initio quantum methods were applied on the indigo molecule, both isolated and linked through H-bonds with water, to calculate the magnitude of the expected vibrational shifts. Calculated and experimental vibrational shifts appeared to be in good agreement. The presence of a peak at 17.8 ppm and the shift of the N-H signal in the 1H MAS NMR spectrum of Maya Blue provide evidence of hydrogen bond interactions between indigo and palygorskite in agreement with IR and ab initio methods. PMID:16853500

  20. 49 CFR 173.216 - Asbestos, blue, brown or white.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Asbestos, blue, brown or white. 173.216 Section 173.216 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Class 7 § 173.216 Asbestos, blue, brown or white. (a) Asbestos, blue, brown or white, includes each...

  1. 49 CFR 173.216 - Asbestos, blue, brown or white.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Asbestos, blue, brown or white. 173.216 Section 173.216 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS... Class 7 § 173.216 Asbestos, blue, brown or white. (a) Asbestos, blue, brown or white, includes each...

  2. 77 FR 55895 - Permanent Closure of Cincinnati Blue Ash Airport

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Federal Aviation Administration Permanent Closure of Cincinnati Blue Ash Airport AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of permanent closure of Cincinnati Blue Ash Airport (ISZ). SUMMARY: The... Cincinnati advising that on August 29, 2012, it was permanently closing Cincinnati Blue Ash Airport...

  3. Is blue light good or bad for plants?

    PubMed

    Dougher, T A; Bugbee, B G

    1998-01-01

    Blue photons are energetically expensive so the most energy-efficient lamps contain the least blue light. Blue photons are not used efficiently in photosynthesis, but blue light has dramatic effects on plant development. We studied the growth and development of soybean, wheat, and lettuce plants under high-pressure sodium and metal halide lamps with yellow filters creating five fractions of blue light (0.5%, 3.5%, 6%, 1 8%, and 26% blue) at 500 micromoles m-2 s-1 and (< 0.1%, 1.7%, 6%, 12%, and 26%) at 200 mol m-2 s-1. The response was species dependent. Lettuce was highly sensitive to blue light fraction and had an optimum dry weight and leaf area at about 6% blue, but results were complicated by sensitivity to lamp type. Wheat and soybean were less sensitive to blue light, but dry mass and leaf area decreased steadily with increasing blue light. Blue light fraction significantly affected specific leaf area (SLA, m2 kg-1) and chlorophyll in lettuce, but had no significant effect on wheat and soybeans. The data suggest that lettuce benefits from some added blue light, but soybean and wheat may not. PMID:11541668

  4. Multicenter Evaluation of MRSASelect II Chromogenic Agar for Identification of Methicillin-Resistant Staphylococcus aureus from Wound and Nasal Specimens

    PubMed Central

    Newton, Duane W.; Ledeboer, Nathan A.; Young, Carol; Clark, Andrew E.; Connoly, Jessica; Wolk, Donna M.

    2015-01-01

    Hospitals strive to reduce methicillin-resistant Staphylococcus aureus (MRSA) prevalence via active surveillance of inpatient populations. Rapid and inexpensive screening methods are utilized when molecular methods are not operationally feasible. In this multisite clinical trial, the utility of Bio-Rad's MRSASelect II was evaluated for MRSA identification from remnant nares and wound swabs. The prevalence of MRSA was 11.1% (n = 1,384) from nares samples and 18.1% (n = 842) from wound samples. MRSASelect II had an overall concordance of 95.4% (confidence interval [CI] = 94.5% to 96.2%) compared to a broth-enriched reference standard. Comparisons between results, stratified by examination times, exhibited a nonsignificant trend toward increased positivity at prolonged incubation times. Cefoxitin screening of colonies directly from MRSASelect II was 96.7% (95.8% to 97.3%) concordant compared to testing of colonies following broth enrichment. A comparison of MRSASelect and MRSASelect II revealed no statistical differences; however, the latter exhibited earlier positivity, greater selectivity, and more intense indicator staining, which resulted in facilitated differentiation of positive results. MRSASelect II agar is a simple, rapid, and robust method to routinely screen patients for MRSA colonization without the need for additional testing. PMID:26582836

  5. Correlation between Agar Plate Screening and Solid-State Fermentation for the Prediction of Cellulase Production by Trichoderma Strains

    PubMed Central

    Florencio, Camila; Couri, Sonia; Farinas, Cristiane Sanchez

    2012-01-01

    The viability of converting biomass into biofuels and chemicals still requires further development towards the reduction of the enzyme production costs. Thus, there is a growing demand for the development of efficient procedures for selection of cellulase-producing microorganisms. This work correlates qualitative screening using agar plate assays with quantitative measurements of cellulase production during cultivation under solid-state fermentation (SSF). The initial screening step consisted of observation of the growth of 78 preselected strains of the genus Trichoderma on plates, using microcrystalline cellulose as carbon source. The 49 strains that were able to grow on this substrate were then subjected to a second screening step using the Congo red test. From this test it was possible to select 10 strains that presented the highest enzymatic indices (EI), with values ranging from 1.51 to 1.90. SSF cultivations using sugarcane bagasse and wheat bran as substrates were performed using selected strains. The CG 104NH strain presented the highest EGase activity (25.93 UI·g−1). The EI results obtained in the screening procedure using plates were compared with cellulase production under SSF. A correlation coefficient (R2) of 0.977 was obtained between the Congo red test and SSF, demonstrating that the two methodologies were in good agreement. PMID:23227312

  6. Mutations in Arabidopsis thaliana genes involved in the tryptophan biosynthesis pathway affect root waving on tilted agar surfaces

    NASA Technical Reports Server (NTRS)

    Rutherford, R.; Gallois, P.; Masson, P. H.

    1998-01-01

    Arabidopsis thaliana roots grow in a wavy pattern upon a slanted surface. A novel mutation in the anthranilate synthase alpha 1 (ASA1) gene, named trp5-2wvc1, and mutations in the tryptophan synthase alpha and beta 1 genes (trp3-1 and trp2-1, respectively) confer a compressed root wave phenotype on tilted agar surfaces. When trp5-2wvc1 seedlings are grown on media supplemented with anthranilate metabolites, their roots wave like wild type. Genetic and pharmacological experiments argue that the compressed root wave phenotypes of trp5-2wvc1, trp2-1 and trp3-1 seedlings are not due to reduced IAA biosynthetic potential, but rather to a deficiency in L-tryptophan (L-Trp), or in a L-Trp derivative. Although the roots of 7-day-old seedlings possess higher concentrations of free L-Trp than the shoot as a whole, trp5-2wvc1 mutants show no detectable alteration in L-Trp levels in either tissue type, suggesting that a very localized shortage of L-Trp, or of a L-Trp-derived compound, is responsible for the observed phenotype.

  7. Antimicrobial Susceptibilities of Commonly Encountered Bacterial Isolates to Fosfomycin Determined by Agar Dilution and Disk Diffusion Methods▿

    PubMed Central

    Lu, Ching-Lan; Liu, Chia-Ying; Huang, Yu-Tsung; Liao, Chun-Hsing; Teng, Lee-Jene; Turnidge, John D.; Hsueh, Po-Ren

    2011-01-01

    We studied the antimicrobial activity of fosfomycin against 960 strains of commonly encountered bacteria associated with urinary tract infection using standard agar dilution and disk diffusion methods. Species studied included 3 common species of Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia; methicillin-susceptible and -resistant Staphylococcus aureus; and vancomycin-susceptible and resistant Enterococcus faecalis and E. faecium. MICs and inhibition zone diameters were interpreted in accordance with both the currently recommended Clinical and Laboratory Standards Institute (CLSI) criteria for urinary tract isolates of Escherichia coli and Enterococcus faecalis and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria for Enterobacteriaceae. Tentative zone diameter interpretive criteria were developed for species not currently published by CLSI or EUCAST. Escherichia coli was uniformly susceptible to fosfomycin, as were most strains of Klebsiella pneumoniae and Enterobacter cloacae. A. baumannii was resistant to fosfomycin, while the prevalence of resistance in P. aeruginosa and S. maltophilia was greatly affected by the choice of MIC breakpoint. New tentative zone diameter criteria for K. pneumoniae, E. cloacae, S. aureus, and E. faecium were able to be set, providing some interim laboratory guidance for disk diffusion until further breakpoint evaluations are undertaken by CLSI and EUCAST. PMID:21670185

  8. Evaluation of Tazobactam-Supplemented, Modified Charcoal-Cefoperazone-Deoxycholate Agar for Qualitative Detection of Campylobacter from Chicken Carcass Rinse.

    PubMed

    Chon, Jung-Whan; Kim, Young-Ji; Kim, Hong-Seok; Kim, Dong-Hyeon; Jeong, Dong Kwan; Seo, Kun-Ho

    2016-05-01

    Overgrowth of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli on modified charcoal-cefoperazone-deoxycholate agar (mCCDA) is the most common confounding factor for the isolation of Campylobacter from poultry samples. mCCDA modified by supplementation with tazobactam, an ESBL inhibitor, was evaluated for Campylobacter isolation from chicken carcass rinse with regard to isolation rate and selectivity. In total, 120 whole chicken carcasses purchased from retail stores were rinsed with buffered peptone water enriched with 2× blood-free Bolton broth at 42°C for 48 h and then inoculated onto mCCDA with and without tazobactam supplementation (mCCDA or T-mCCDA) at 42°C for 48 h under microaerobic conditions. Suspect colonies were subcultured and confirmed by colony PCR. Plates with tazobactam exhibited a higher Campylobacter isolation rate (56.7% vs. 30.8%, p < 0.05) and selectivity (0.8 vs. 83.3% plates contaminated with non-Campylobacter, p < 0.05) than mCCDA. Thus, tazobactam-supplemented mCCDA would be a useful option for qualitative detection of Campylobacter in chicken carcass rinse. PMID:27043031

  9. Analysis of Keystone Enzyme in Agar Hydrolysis Provides Insight into the Degradation (of a Polysaccharide from) Red Seaweeds*

    PubMed Central

    Hehemann, Jan-Hendrik; Smyth, Leo; Yadav, Anuj; Vocadlo, David J.; Boraston, Alisdair B.

    2012-01-01

    Agars are abundant polysaccharides from marine red algae, and their chemical structure consists of alternating d-galactose and 3,6-anhydro-l-galactose residues, the latter of which are presumed to make the polymer recalcitrant to degradation by most terrestrial bacteria. Here we study a family 117 glycoside hydrolase (BpGH117) encoded within a recently discovered locus from the human gut bacterium Bacteroides plebeius. Consistent with this locus being involved in agarocolloid degradation, we show that BpGH117 is an exo-acting 3,6-anhydro-α-(1,3)-l-galactosidase that removes the 3,6-anhydrogalactose from the non-reducing end of neoagaro-oligosaccharides. A Michaelis complex of BpGH117 with neoagarobiose reveals the distortion of the constrained 3,6-anhydro-l-galactose into a conformation that favors catalysis. Furthermore, this complex, supported by analysis of site-directed mutants, provides evidence for an organization of the active site and positioning of the catalytic residues that are consistent with an inverting mechanism of catalysis and suggests that a histidine residue acts as the general acid. This latter feature differs from the vast majority of glycoside hydrolases, which use a carboxylic acid, highlighting the alternative strategies that enzymes may utilize in catalyzing the cleavage of glycosidic bonds. PMID:22393053

  10. The use of antibiotics to improve phage detection and enumeration by the double-layer agar technique

    PubMed Central

    2009-01-01

    Background The Double-Layer Agar (DLA) technique is extensively used in phage research to enumerate and identify phages and to isolate mutants and new phages. Many phages form large and well-defined plaques that are easily observed so that they can be enumerated when plated by the DLA technique. However, some give rise to small and turbid plaques that are very difficult to detect and count. To overcome these problems, some authors have suggested the use of dyes to improve the contrast between the plaques and the turbid host lawns. It has been reported that some antibiotics stimulate bacteria to produce phages, resulting in an increase in final titer. Thus, antibiotics might contribute to increasing plaque size in solid media. Results Antibiotics with different mechanisms of action were tested for their ability to enhance plaque morphology without suppressing phage development. Some antibiotics increased the phage plaque surface by up to 50-fold. Conclusion This work presents a modification of the DLA technique that can be used routinely in the laboratory, leading to a more accurate enumeration of phages that would be difficult or even impossible otherwise. PMID:19627589

  11. Comparison of agar dilution and antibiotic gradient strip test with broth microdilution for susceptibility testing of swine Brachyspira species.

    PubMed

    Mirajkar, Nandita S; Gebhart, Connie J

    2016-03-01

    Production-limiting diseases in swine caused by Brachyspira are characterized by mucohemorrhagic diarrhea (B. hyodysenteriae and "B. hampsonii") or mild colitis (B. pilosicoli), while B. murdochii is often isolated from healthy pigs. Emergence of novel pathogenic Brachyspira species and strains with reduced susceptibility to commonly used antimicrobials has reinforced the need for standardized susceptibility testing. Two methods are currently used for Brachyspira susceptibility testing: agar dilution (AD) and broth microdilution (BMD). However, these tests have primarily been used for B. hyodysenteriae and rarely for B. pilosicoli. Information on the use of commercial susceptibility testing products such as antibiotic gradient strips is lacking. Our main objective was to validate and compare the susceptibility results, measured as the minimum inhibitory concentration (MIC), of 6 antimicrobials for 4 Brachyspira species (B. hyodysenteriae, "B. hampsonii", B. pilosicoli, and B. murdochii) by BMD and AD (tiamulin, valnemulin, lincomycin, tylosin, and carbadox) or antibiotic gradient strip (doxycycline) methods. In general, the results of a high percentage of all 4 Brachyspira species differed by ±1 log2 dilution or less by BMD and AD for tiamulin, valnemulin, lincomycin, and tylosin, and by BMD and antibiotic gradient strip for doxycycline. The carbadox MICs obtained by BMD were 1-5 doubling dilutions different than those obtained by AD. BMD for Brachyspira was quicker to perform with less ambiguous interpretation of results when compared with AD and antibiotic gradient strip methods, and the results confirm the utility of BMD in routine diagnostics. PMID:26965233

  12. Evaluation of isolation procedures and chromogenic agar media for the detection of MRSA in nasal swabs from pigs and veal calves.

    PubMed

    Graveland, Haitske; van Duijkeren, Engeline; van Nes, Arie; Schoormans, Anky; Broekhuizen-Stins, Marian; Oosting-van Schothorst, Isabella; Heederik, Dick; Wagenaar, Jaap A

    2009-10-20

    Since the emergence of MRSA in livestock, screening of animals for the detection of MRSA is widely practised. Different procedures are published for animal samples but a systematic comparison of methods has not been performed. The objective of this study was to compare three available commonly used procedures and three chromogenic agars for detecting MRSA in nasal swabs from pigs (n=70) and veal calves (n=100). Procedures 1 and 2 used a pre-enrichment comprising Mueller Hinton broth with 6.5% NaCl followed by selective enrichment with 4 microg/ml oxacillin+75 microg/ml aztreonam (procedure 1) and 5 microg/ml ceftizoxime+75 microg/ml aztreonam (procedure 2) respectively. Procedure 3 used a selective enrichment broth only, containing 4% NaCl, 5 microg/ml ceftizoxime+50 microg/ml aztreonam. After selective enrichment, media were streaked on to three different chromogenic agars. Significantly more MRSA were found for pig as well as for veal calf samples with procedures 1 and 2. No significant differences were found between procedures 1 and 2. For nasal swabs from pigs significantly more MRSA-positive samples were found when MRSA Screen (Oxoid) or MRSASelect (Bio-Rad) agars were used compared to MSRA ID (bioMrieux). For calf samples no significant differences between the different agars were found. In conclusion, the results of this study show that procedures 1 and 2, both using additional high salt pre-enrichment are superior and should be recommended for MRSA detection in nasal swabs from pigs and veal calves. The preferred choice of chromogenic agar depends on the sample matrix. PMID:19559546

  13. Comparison of the Agar Block and Lieber-DeCarli Diets to Study Chronic Alcohol Consumption in an Aging Model of Fischer 344 Female Rats

    PubMed Central

    Sharda, Daniel R.; Miller-Lee, Jennifer L.; Kanski, Gregory M.; Hunter, J. Craig; Lang, Charles H.; Kennett, Mary J.; Korzick, Donna H.

    2012-01-01

    Introduction Post-menopausal women have a greater risk of developing alcoholic complications compared to age-matched men. Unfortunately, animal models of chronic ethanol consumption with estrogen deficiency are lacking. Here, we characterize the ability of the agar block and Lieber-DeCarli models of chronic ethanol consumption to produce elevated blood alcohol content (BAC) and liver pathology in the F344 postmenopausal animal model of aging. Methods Adult (3 mo) and aged (18 mo) F344 ovary-intact or ovariectomized rats were administered ethanol for 14-20 weeks as follows: diet 1, standard chow access, 10% ethanol in drinking water, and 40% ethanol in agar blocks; diet 2, diet 1 plus low phytoestrogen chow (known to effect ethanol metabolism) for the final 4 weeks; diet 3, Lieber-DeCarli all liquid diet with 36% kcal ethanol. Control animals were matched isocalorically with dextrin. Results For the agar block diet, average BAC was 13 ± 4 mg/dL across groups. BAC was unaffected by reducing dietary phytoestrogen content (12 ± 4 mg/dL), which is known to interfere with ethanol metabolism. Liver pathology was unaffected by the agar block diet. In contrast, the Lieber-DeCarli diet resulted in BAC of 45 ± 5 mg/dL in conjunction with more severe hepatopathology. Discussion We conclude that the Lieber-DeCarli diet produces greater BAC and hepatopathology to study the effects of chronic ethanol administration in the F344 postmenopausal rodent model of aging when compared to an ethanol agar block diet. PMID:22951285

  14. Phycobilisomes in Blue-Green Algae

    PubMed Central

    Wildman, Ruth B.; Bowen, C. C.

    1974-01-01

    Fifteen species of freshwater blue-green algae, including unicellular, filamentous, and colonial forms, were subjected to a variety of fixatives, fixation conditions, and stains for comparison of the preservation of phycobilisomes. Absorption spectra of the corresponding in vivo and released photosynthetic pigments, in 10 of the species that were maintained in culture, demonstrated the presence of phycocyanin in all 10 species and phycoerythrin in only 2 of them. Spectroscope and electron microscope evidence was obtained for localization of phycobiliproteins in phycobilisomes of Nostoc muscorum. Phycobilisomes were observed in all species examined in situ, strenghening the hypothesis that phycobilisomes are common to all phycobiliprotein-containing photosynthetic blue-green algae. Images PMID:4204443

  15. Colloidal particles in blue phase liquid crystals.

    PubMed

    Pawsey, Anne C; Clegg, Paul S

    2015-05-01

    We study the effect of disorder on the phase transitions of a system already dominated by defects. Micron-sized colloidal particles are dispersed chiral nematic liquid crystals which exhibit a blue phase (BP). The colloids are a source of disorder, disrupting the liquid crystal as the system is heated from the cholesteric to the isotropic phase through the blue phase. The colloids act as a preferential site for the growth of BPI from the cholesteric; in high chirality samples BPII also forms. In both BPI and BPII the colloids lead to localised melting to the isotropic, giving rise to faceted isotropic inclusions. This is in contrast to the behaviour of a cholesteric LC where colloids lead to system spanning defects. PMID:25698218

  16. Experiencing Blues at the Crossroads: A Place-Based Method for Teaching the Geography of Blues Culture

    ERIC Educational Resources Information Center

    Strait, John

    2012-01-01

    This article offers a pedagogical module that explores the geography of blues culture across the Mississippi Delta. By focusing on blues culture, rather than simply blues music itself, this project provides a forum for understanding the broader geographical conditions from which this musical form emerged. This module utilizes place-based

  17. Experiencing Blues at the Crossroads: A Place-Based Method for Teaching the Geography of Blues Culture

    ERIC Educational Resources Information Center

    Strait, John

    2012-01-01

    This article offers a pedagogical module that explores the geography of blues culture across the Mississippi Delta. By focusing on blues culture, rather than simply blues music itself, this project provides a forum for understanding the broader geographical conditions from which this musical form emerged. This module utilizes place-based…

  18. Chitosan/Prussian blue-based biosensors

    NASA Astrophysics Data System (ADS)

    Wang, Yiting; Zhu, Jianzhong; Zhu, Rongjin; Zhu, Ziqiang; Lai, Zongsheng; Chen, Zongyou

    2003-06-01

    Chitosan/Prussian blue (PB) based biosensors, including a glucose sensor, a glutamate sensor and a galactose sensor have been developed. The biosensors exhibit excellent performance; in particular, the interference of ascorbic and uric acids can be avoided due to selective permeability of chitosan film and electro-catalysis of the PB layer to H2O2. The biosensors have been applied to detect glucose, galactose and glutamate in human blood serum and fermented solution.

  19. Luminescence conversion of blue light emitting diodes

    NASA Astrophysics Data System (ADS)

    Schlotter, P.; Schmidt, R.; Schneider, J.

    Using blue-emitting GaN/6HSiC chips as primary light sources, we have fabricated green, yellow, red and white emitting LEDs. The generation of mixed colors, as turquoise and magenta is also demonstrated. The underlying physical principle is that of luminescence down-conversion (Stokes shift), as typical for organic luminescent dye molecules. A white emitting LED, using an inorganic converter, Y3Al5O12:Ce3+( ), has also been realized.

  20. Eta Carinae and Other Luminous Blue Variables

    NASA Technical Reports Server (NTRS)

    Corcoran, M. F.

    2006-01-01

    Luminous Blue Variables (LBVs) are believed to be evolved, extremely massive stars close to the Eddington Limit and hence prone to bouts of large-scale, unstable mass loss. I discuss current understanding of the evolutionary state of these objects, the role duplicity may play and known physical characteristics of these stars using the X-ray luminous LBVs Eta Carinae and HD 5980 as test cases.

  1. Automated detection of Antarctic blue whale calls.

    PubMed

    Socheleau, Francois-Xavier; Leroy, Emmanuelle; Pecci, Andres Carvallo; Samaran, Flore; Bonnel, Julien; Royer, Jean-Yves

    2015-11-01

    This paper addresses the problem of automated detection of Z-calls emitted by Antarctic blue whales (B. m. intermedia). The proposed solution is based on a subspace detector of sigmoidal-frequency signals with unknown time-varying amplitude. This detection strategy takes into account frequency variations of blue whale calls as well as the presence of other transient sounds that can interfere with Z-calls (such as airguns or other whale calls). The proposed method has been tested on more than 105 h of acoustic data containing about 2200 Z-calls (as found by an experienced human operator). This method is shown to have a correct-detection rate of up to more than 15% better than the extensible bioacoustic tool package, a spectrogram-based correlation detector commonly used to study blue whales. Because the proposed method relies on subspace detection, it does not suffer from some drawbacks of correlation-based detectors. In particular, it does not require the choice of an a priori fixed and subjective template. The analytic expression of the detection performance is also derived, which provides crucial information for higher level analyses such as animal density estimation from acoustic data. Finally, the detection threshold automatically adapts to the soundscape in order not to violate a user-specified false alarm rate. PMID:26627784

  2. QCD and the BlueGene

    SciTech Connect

    Vranas, P

    2007-06-18

    Quantum Chromodynamics is the theory of nuclear and sub-nuclear physics. It is a celebrated theory and one of its inventors, F. Wilczek, has termed it as '... our most perfect physical theory'. Part of this is related to the fact that QCD can be numerically simulated from first principles using the methods of lattice gauge theory. The computational demands of QCD are enormous and have not only played a role in the history of supercomputers but are also helping define their future. Here I will discuss the intimate relation of QCD and massively parallel supercomputers with focus on the Blue Gene supercomputer and QCD thermodynamics. I will present results on the performance of QCD on the Blue Gene as well as physics simulation results of QCD at temperatures high enough that sub-nuclear matter transitions to a plasma state of elementary particles, the quark gluon plasma. This state of matter is thought to have existed at around 10 microseconds after the big bang. Current heavy ion experiments are in the quest of reproducing it for the first time since then. And numerical simulations of QCD on the Blue Gene systems are calculating the theoretical values of fundamental parameters so that comparisons of experiment and theory can be made.

  3. The Blue Comet: A Railroad's Astronomical Heritage

    NASA Astrophysics Data System (ADS)

    Rumstay, Kenneth S.

    2009-01-01

    Between 1929 February 21 and 1941 September 27, the Central New Jersey Railroad operated a luxury passenger train between Jersey City and Atlantic City. Named The Blue Comet, the locomotive, tender, and coaches sported a unique royal blue paint scheme designed to evoke images of celestial bodies speeding through space. Inside each car were etched window panes and lampshades featuring stars and comets. And each coach sported the name of a famous comet on its side; these comets were of course named for their discoverers. Some of the astronomers honored in this unique fashion remain famous to this day, or at least their comets do. The names D'Arrest, Barnard, Encke, Faye, Giacobini, Halley, Olbers, Temple, Tuttle, and Westphal are familiar ones. But Biela, Brorsen, deVico, Spitaler, and Winnecke have now largely faded into obscurity; their stories are recounted here. Although more than sixty years have elapsed since its last run, The Blue Comet, perhaps the most famous passenger train in American history, lives on in the memories of millions of passengers and railfans. This famous train returned to the attention of millions of television viewers on the evening of 2007 June 3, in an episode of the HBO series The Sopranos. This work was supported by a faculty development grant from Valdosta State University.

  4. Collimated blue light generation in rubidium vapor

    NASA Astrophysics Data System (ADS)

    Kienlen, Marcus B.; Holte, Noah T.; Dassonville, Hunter A.; Dawes, Andrew M. C.; Iversen, Kurt D.; McLaughlin, Ryan M.; Mayer, Shannon K.

    2013-06-01

    We describe an experiment for generating and characterizing a beam of collimated blue light (CBL) in a rubidium vapor. Two low-power, grating-feedback diode lasers, operating at 780.2 nm (5S1/2→5P3/2) and 776.0 nm (5P3/2→5D5/2), respectively, provide step-wise excitation to the 5D excited state in rubidium. Under the right experimental conditions, cascade decay through the 6P excited state will yield a collimated blue (420-nm) beam of light with high temporal and spatial coherence. We investigate the production of a blue beam under a variety of experimental conditions and characterize the spatial coherence and spectral characteristics. This experiment provides advanced undergraduate students with a unique opportunity to investigate nonlinear optical phenomena in the laboratory and uses equipment that is commonly available in laboratories equipped to investigate diode-laser-based absorption spectroscopy in rubidium.

  5. Methylene blue promotes quiescence of rat neural progenitor cells

    PubMed Central

    Xie, Luokun; Choudhury, Gourav R.; Wang, Jixian; Park, Yong; Liu, Ran; Yuan, Fang; Zhang, Chun-Li; Yorio, Thomas; Jin, Kunlin; Yang, Shao-Hua

    2014-01-01

    Neural stem cell-based treatment holds a new therapeutic opportunity for neurodegenerative disorders. Here, we investigated the effect of methylene blue on proliferation and differentiation of rat neural progenitor cells (NPCs) both in vitro and in vivo. We found that methylene blue inhibited proliferation and promoted quiescence of NPCs in vitro without affecting committed neuronal differentiation. Consistently, intracerebroventricular infusion of methylene blue significantly inhibited NPC proliferation at the subventricular zone (SVZ). Methylene blue inhibited mTOR signaling along with down-regulation of cyclins in NPCs in vitro and in vivo. In summary, our study indicates that methylene blue may delay NPC senescence through enhancing NPCs quiescence. PMID:25339866

  6. Gilvimarinus polysaccharolyticus sp. nov., an agar-digesting bacterium isolated from seaweed, and emended description of the genus Gilvimarinus.

    PubMed

    Cheng, Hong; Zhang, Shun; Huo, Ying-Yi; Jiang, Xia-Wei; Zhang, Xin-Qi; Pan, Jie; Zhu, Xu-Fen; Wu, Min

    2015-02-01

    A taxonomic study was carried out on strain YN3(T), which was isolated from a seaweed sample taken from the coast of Weihai, China. The bacterium was Gram-stain-negative, rod-shaped, and could grow at pH 5.0-10.0 and 4-32 °C in the presence of 0-9.0 % (w/v) NaCl. Strain YN3(T) was positive for the hydrolysis of polysaccharides, such as agar, starch and xylan. The predominant respiratory quinone was ubiquinone-8. The major fatty acids were C16 : 1ω7c and/or iso-C15 : 0 2-OH, C16 : 0 and C18 : 1ω7c. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine, and two unidentified glycolipids. The genomic DNA G+C content was 49.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YN3(T) should be assigned to the genus Gilvimarinus. 'Gilvimarinus agarilyticus' KCTC 23325 and Gilvimarinus chinensis QM42(T) had the closest phylogenetic relationship to strain YN3(T), and showed 97.9 % and 95.8 % sequence similarities, respectively. On the basis of phenotypic, chemotaxonomic and genotypic data and DNA-DNA hybridization studies, we propose that strain YN3(T) represents a novel species of the genus Gilvimarinus, for which the name Gilvimarinus polysaccharolyticus sp. nov. is proposed. The type strain is YN3(T) ( = KCTC 32438(T) = JCM 19198(T)). An emended description of the genus Gilvimarinus is also presented. PMID:25392347

  7. VIDAS Salmonella (SLM) assay method EasySLM with ChromID Salmonella (SM2) Agar. Performance Tested Method 020901.

    PubMed

    Johnson, Ronald; Mills, John; Colón-Reveles, Judith

    2009-01-01

    A method modification study was conducted for the VIDAS Salmonella (SLM) assay (AOAC Performance Tested Method 020901) using the EasySLM method to validate a matrix extension for peanut butter. The VIDAS EasySLM method is a simple enrichment procedure compared to traditional Salmonella methods, requiring only pre-enrichment and a single selective enrichment media, Salmonella Xpress 2 (SX2) broth. SX2 replaces the two selective broths in traditional methods and eliminates the M broth transfer, incubation, and subsequent pooling of M broths prior to VIDAS assay. The validation study was conducted under the AOAC Research Institute Emergency Response Validation program. VIDAS SLM was compared to the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) method for detection of S. enterica ser. Typhimurium in peanut butter. All peanut butter samples were prepared, blind-coded, and shipped to the method developers' laboratory by Q Laboratories. In addition, Q Laboratories performed most probable number and reference method analyses on peanut butter samples. The VIDAS EasySLM ChromID Salmonella (SM2) Agar was previously validated in the Performance Tested Methods program for the detection of Salmonella in roast beef, raw ground pork, turkey, pork sausage, raw chicken breast, dry pet food, whole milk, ice cream, bagged spinach, shrimp (raw, peeled), raw cod, spent irrigation water, pecans, peanut butter, dry pasta, cake mix, ground black pepper, nonfat dry milk, liquid eggs, cantaloupe, and orange juice. In the matrix extension study for peanut butter, the VIDAS EasySLM method was shown to be equivalent to the appropriate reference culture procedure using both buffered peptone water pre-enrichment and the FDA-BAM lactose pre-enrichment in the two-step enrichment method with SX2 media. The current study extends the validation to include peanut butter. PMID:20166608

  8. Accumulation of dibenzocyclooctadiene lignans in agar cultures and in stationary and agitated liquid cultures of Schisandra chinensis (Turcz.) Baill.

    PubMed

    Szopa, Agnieszka; Kokotkiewicz, Adam; Marzec-Wróblewska, Urszula; Bucinski, Adam; Luczkiewicz, Maria; Ekiert, Halina

    2016-05-01

    Schisandra chinensis plant in vitro cultures were maintained on Murashige and Skoog (MS) medium supplemented with 3 mg/l 6-benzyladenine (BA) and 1 mg/l 1-naphthaleneacetic acid (NAA) in an agar system and also in two different liquid systems: stationary and agitated. Liquid cultures were grown in batch (30 and 60 days) and fed-batch modes. In the methanolic extracts from lyophilized biomasses and in the media, quantification of fourteen dibenzocyclooctadiene lignans identified based on co-chromatography with authentic standards using high-performance liquid chromatography with diode array detection (HPLC-DAD) and/or liquid chromatography with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI-MS) methods. For comparison purposes, phytochemical analyses were performed of lignans in the leaves and fruits of the parent plant. The main lignans detected in the biomass extracts from all the tested systems were schisandrin (max. 65.62 mg/100 g dry weight (DW)), angeloyl-/tigloylgomisin Q (max. 49.73 mg/100 g DW), deoxyschisandrin (max. 43.65 mg/100 g DW), and gomisin A (max. 34.36 mg/100 g DW). The highest total amounts of lignans in the two tested stationary systems were found in extracts from the biomass harvested after 30 days of batch cultivation: 237.86 mg/100 g DW and 274.65 mg/100 g DW, respectively. In the agitated culture, the total content reached a maximum value of 244.80 mg/100 g DW after 60 days of the fed-batch mode of cultivation. The lignans were not detected in the media. This is the first report which documents the potential usefulness of S. chinensis shoot cultures cultivated in liquid systems for practical purposes. PMID:26685855

  9. Compensation of blue phase I by blue phase II in optoeletronic device.

    PubMed

    Lan, Yi-Fen; Tsai, Cheng-Yeh; Lu, Jen-Kuei; Sugiura, Norio

    2013-02-25

    Compensation effect of blue phase I (BP I) with blue phase II (BP II) liquid crystal was demonstrated. BP I and BP II were co-exist in the optoeletronic device by polymer stabilization. Consequently, disadvantages of BP I and BP II were greatly improved by compensation effect and resulted in high contrast ratio, low hysteresis and fast falling time. Mechanism of compensation effect was explained by relaxation ability of lattice structure under electrical field and compensation structure was well confirmed by Bragg's reflectance spectrum and Commission International de l'Éclairage chromaticity diagram. PMID:23482036

  10. MOCK OBSERVATIONS OF BLUE STRAGGLERS IN GLOBULAR CLUSTER MODELS

    SciTech Connect

    Sills, Alison; Glebbeek, Evert; Chatterjee, Sourav; Rasio, Frederic A. E-mail: e.glebbeek@astro.ru.nl E-mail: rasio@northwestern.edu

    2013-11-10

    We created artificial color-magnitude diagrams of Monte Carlo dynamical models of globular clusters and then used observational methods to determine the number of blue stragglers in those clusters. We compared these blue stragglers to various cluster properties, mimicking work that has been done for blue stragglers in Milky Way globular clusters to determine the dominant formation mechanism(s) of this unusual stellar population. We find that a mass-based prescription for selecting blue stragglers will select approximately twice as many blue stragglers than a selection criterion that was developed for observations of real clusters. However, the two numbers of blue stragglers are well-correlated, so either selection criterion can be used to characterize the blue straggler population of a cluster. We confirm previous results that the simplified prescription for the evolution of a collision or merger product in the BSE code overestimates their lifetimes. We show that our model blue stragglers follow similar trends with cluster properties (core mass, binary fraction, total mass, collision rate) as the true Milky Way blue stragglers as long as we restrict ourselves to model clusters with an initial binary fraction higher than 5%. We also show that, in contrast to earlier work, the number of blue stragglers in the cluster core does have a weak dependence on the collisional parameter Γ in both our models and in Milky Way globular clusters.

  11. Nile Blue derivatives as lysosomotropic photosensitizers

    NASA Astrophysics Data System (ADS)

    Lin, Chi-Wei; Shulok, Janine R.; Kirley, S. D.; Cincotta, Louis; Foley, James W.

    1991-06-01

    The benzophenoxazines, including several Nile blue analogues, are a unique group of dyes that localize selectively in animal tumors. Chemical modifications of Nile blue A can yield derivatives with high 1O2 quantum yields. These derivatives represent a group of potentially effective photosensitizers for selective phototherapy of malignant tumors. In vitro evaluation of these derivatives has indicated that those with high 1O2 yields are very effective in mediating the photocytotoxicity of tumor cells. This photodynamic effect is most likely mediated through the action of 1O2, since photoirradiation under D2O enhanced and under hypoxic conditions diminished the photocytotoxic action. The subcellular localization of these photosensitizers in bladder tumor cells in culture was examined by light and fluorescence microscopies as well as by histochemical and biochemical studies. The results indicate that these dyes are localized primarily in the lysosome. The cellular uptake and retention of these dyes is energy- and pH-dependent. Agents such as nigericin, which alter the transmembrane pH gradient, reduced uptake and enhanced efflux of the dyes, while agents such as valinomycin, which reduce cellular membrane potential, had no effect on the uptake. These findings are consistent with having ion-trapping as the mechanism for the uptake of these dyes. Photoirradiation of sensitizer-treated cells obliterated lysosomes in a light-dose and drug-dose dependent fashion. Release of the hydrolytic enzymes may be the main cause for subsequent cell death since the cytolytic effect was reduced by a specific inhibitor of lysosomal proteolytic enzyme. A lysosomotropic photosensitization mechanism is therefore proposed for the photocytotoxic action of the Nile blue derivatives. This mechanism may provide an approach to the development of new photosensitizers for the effective and selective destruction of malignant tumors.

  12. Extreme and Intermediate Blue Horizontal Branch Stars

    NASA Astrophysics Data System (ADS)

    D'Cruz, N.; Rood, R.; O'Connell, R.; Dorman, B.; Dickens, R.

    1996-12-01

    The blue horizontal branch population consists of extreme horizontal branch (EHB) stars and the cooler intermediate blue horizontal branch (IBHB) stars. EHB stars have very tiny hydrogen envelopes (<= 0.05M_sun) as a result of extreme mass loss during the red giant branch (RGB) phase. They occupy a small range in mass and evolve at high effective temperatures after core He exhaustion. Their prodigious UV emission makes them the leading contenders for the source of the ultraviolet excess phenomenon seen in elliptical galaxies and spiral bulges. Using our stellar evolution code, STEV, we have studied the effects of extreme RGB mass loss on the HB over the metallicity range -2.26 <= [Fe/H] <= +0.37. Mass loss followed Reimers' mass loss formula. Extreme mass loss causes some stars to end their lives as He white dwarfs; the others ignite He at high temperatures and form a ``blue hook'' at the blue end of the canonical Zero-Age HB. We considered the distribution of initial HB masses as a probability distribution in Reimers' mass loss efficiency parameter, etaR, rather than directly as a mass probability distribution. For globular cluster abundances, the range of etaR producing EHB stars was comparable to that producing normal HB stars. As metallicity is increased, the range and magnitude of etaR varies only slightly, whereas the range of etaR producing mid-HB stars becomes very small, implying that the HB will be bimodal provided etaR is large enough. Further details can be found in ApJ, 466, 359 (1996). To determine how etaR might vary with metallicty, we have obtained fiber spectra of IBHB stars in the globular cluster omega Cen using the 3.9m Anglo-Australian telescope. T_eff, log g and [Ca/H] are being determined from the spectra. Our initial analysis indicates that for stars in the 7500 - 8200 K range, the distribution of [Ca/H] in the IBHB stars is different from that of omega Cen's giants and variables. There are comparatively more lower metallicity IBHB stars. This work is still in progress.

  13. Blue running of the primordial tensor spectrum

    SciTech Connect

    Gong, Jinn-Ouk

    2014-07-01

    We examine the possibility of positive spectral index of the power spectrum of the primordial tensor perturbation produced during inflation in the light of the detection of the B-mode polarization by the BICEP2 collaboration. We find a blue tilt is in general possible when the slow-roll parameter decays rapidly. We present two known examples in which a positive spectral index for the tensor power spectrum can be obtained. We also briefly discuss other consistency tests for further studies on inflationary dynamics.

  14. Slow-blue PanSTARRS transients

    NASA Astrophysics Data System (ADS)

    MacLeod, Chelsea L.; Bruce, Alastair; Lawrence, Andy; Ward, Martin; Collinson, James; Elvis, Martin; Gezari, Suvi; Smartt, Steven; Smith, Ken; Wright, Darryl; Fraser, Morgan

    2015-01-01

    Photometric and spectroscopic monitoring of 50 blue, nuclear "transients" in PanSTARRS-1 has revealed different types of extremely variable AGN. The majority show a gradual brightening by ~2 mag from the SDSS observation a decade ago and may represent a new class of AGN microlensed by foreground galaxies. Spectra from the William Herschel Telescope identify these as z~1 AGN with atypical spectroscopic properties. We present an analysis of their photometric and spectroscopic variability in an effort to constrain the detailed structure of the source AGN.

  15. Blue Marble Space Institute essay contest

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-04-01

    The Blue Marble Space Institute of Science, based in Seattle, Wash., is inviting college students to participate in its essay contest. Essays need to address the question, "In the next 100 years, how can human civilization prepare for the long-term changes to the Earth system that will occur over the coming millennium?" According to the institute, the purpose of the contest is "to stimulate creative thinking relating to space exploration and global issues by exploring how changes in the Earth system will affect humanity's future."

  16. Crystalline lens capsule staining with trypan blue.

    PubMed

    Laureano, Joseph San; Coroneo, Minas T

    2004-10-01

    A 1-step method for staining the anterior lens capsule with trypan blue is described. The dye is instilled via a paracentesis port at the start of cataract extraction. As aqueous humor is allowed to exit the anterior chamber (AC), which consequently shallows, the resulting pupil block confines the dye to the AC. An ophthalmic viscosurgical device (OVD) is used to flush dye-stained aqueous from the AC, circumventing the need for AC washout. Although the OVD may be tinged with dye, this does not impede performing capsulorhexis. This method does not add to the surgical time, requires no additional instruments or materials, and is safe. PMID:15474812

  17. Trypan blue dye for anterior segment surgeries

    PubMed Central

    Jhanji, V; Chan, E; Das, S; Zhang, H; Vajpayee, R B

    2011-01-01

    Use of vital dyes in ophthalmic surgery has gained increased importance in the past few years. Trypan blue (TB) has been a popular choice among anterior segment surgeons mainly due to its safety, ease of availability, and remarkable ability to enable an easy surgery in difficult situations mostly related to visibility of the targeted tissue. It is being used in cataract surgery since nearly a decade and its utilization has been extended to other anterior segment surgeries like trabeculectomy and corneal transplantation. This review will discuss the techniques and outcome of TB dye-assisted anterior segment surgeries. PMID:21681214

  18. Blue, green, orange, and red upconversion laser

    DOEpatents

    Xie, P.; Gosnell, T.R.

    1998-09-08

    A laser is disclosed for outputting visible light at the wavelengths of blue, green, orange and red light. This is accomplished through the doping of a substrate, such as an optical fiber or waveguide, with Pr{sup 3+} ions and Yb{sup 3+} ions. A light pump such as a diode laser is used to excite these ions into energy states which will produce lasing at the desired wavelengths. Tuning elements such as prisms and gratings can be employed to select desired wavelengths for output. 11 figs.

  19. Blue, green, orange, and red upconversion laser

    DOEpatents

    Xie, Ping; Gosnell, Timothy R.

    1998-01-01

    A laser for outputting visible light at the wavelengths of blue, green, orange and red light. This is accomplished through the doping of a substrate, such as an optical fiber or waveguide, with Pr.sup.3+ ions and Yb.sup.3+ ions. A light pump such as a diode laser is used to excite these ions into energy states which will produce lasing at the desired wavelengths. Tuning elements such as prisms and gratings can be employed to select desired wavelengths for output.

  20. Spectroscopic surveys of faint blue stars

    NASA Technical Reports Server (NTRS)

    Wegner, Gary; Boley, Forrest I.; Swanson, Steven R.; Mcmahan, Robert K.

    1987-01-01

    Spectroscopy of 450 faint blue stars obtained with the spectrograph and intensified Reticon scanner on the 1.3 m telescope at the McGraw Hill Observatory located at Kitt Peak are examined. The study is limited to objects brighter than V = 17.0 in magnitude. It is found that the relative numbers of objects such as white dwarfs, QSOs and CVs in the Kisco survey (Noguchi et al. 1980) is similar to that in the survey of Green et al., (1986).

  1. Measuring star formation rates in blue galaxies

    NASA Technical Reports Server (NTRS)

    Gallagher, John S., III; Hunter, Deidre A.

    1987-01-01

    The problems associated with measurements of star formation rates in galaxies are briefly reviewed, and specific models are presented for determinations of current star formation rates from H alpha and Far Infrared (FIR) luminosities. The models are applied to a sample of optically blue irregular galaxies, and the results are discussed in terms of star forming histories. It appears likely that typical irregular galaxies are forming stars at nearly constant rates, although a few examples of systems with enhanced star forming activity are found among HII regions and luminous irregular galaxies.

  2. Pulsational Mass Loss in Luminous Blue Variables

    NASA Astrophysics Data System (ADS)

    Lovekin, C. C.; Guzik, J. A.

    2012-12-01

    Luminous Blue Variables are evolved stars which experience periods of enhanced mass loss and outbursts. During these outbursts, the star stays at constant luminosity, but appears to become cooler. The S Doradus type variability, unlike the more extreme eruptions seen in η Car, occur on timescales of years to decades. The origin of the variability is still not understood, nor is the connection to extreme objects such as η Car. In this work, we examine hydrodynamic models of radial pulsation including time-dependent convection in massive stars, looking for the conditions necessary to trigger S Doradus type variability.

  3. Historical sources about diseases, death and embalming regarding the family of Jean Antoine Michel Agar, Minister of Finance of Gioacchino Murat.

    PubMed

    Marinozzi, S; Gazzaniga, V; Giuffra, V; Fornaciari, G

    2011-06-01

    Among the mummies preserved in the Basilica of San Domenico Maggiore in Naples, there are the bodies of the wife and three children of Jean Antoine Michel Agar, Minister of Finance of Naple's Kingdom during the Monarchy of Joachim Murat (1808-1815). Between 1983 and 1987 paleopathological analyses were performed; in particular, X-ray examination allowed investigation of the health status of the Agar family members and reconstruction of the embalming processes used to preserve the bodies. In addition, an analysis of the historical and archival documents was carried out, to formulate hypotheses about the causes of death, demonstrating how these sources could become important instruments to obtain diagnoses and pathological histories. PMID:22043603

  4. Evaluation of Five Chromogenic Agar Media and the Rosco Rapid Carb Screen Kit for Detection and Confirmation of Carbapenemase Production in Gram-Negative Bacilli

    PubMed Central

    Gilmour, Matthew W.; DeGagne, Pat; Nichol, Kim; Karlowsky, James A.

    2014-01-01

    An efficient workflow to screen for and confirm the presence of carbapenemase-producing Gram-negative bacilli was developed by evaluating five chromogenic screening agar media and two confirmatory assays, the Rapid Carb screen test (Rosco Diagnostica A/S, Taastrup, Denmark) and the modified Hodge test. A panel of 150 isolates was used, including 49 carbapenemase-producing isolates representing a variety of β-lactamase enzyme classes. An evaluation of analytical performance, assay cost, and turnaround time indicated that the preferred workflow (screening test followed by confirmatory testing) was the chromID Carba agar medium (bioMérieux, Marcy l'Étoile, France), followed by the Rapid Carb screen test, yielding a combined sensitivity of 89.8% and a specificity of 100%. As an optional component of the workflow, a determination of carbapenemase gene class via molecular means could be performed subsequent to confirmatory testing. PMID:25355764

  5. Preparation of nanocellulose from micro-crystalline cellulose: The effect on the performance and properties of agar-based composite films.

    PubMed

    Shankar, Shiv; Rhim, Jong-Whan

    2016-01-01

    A facile approach has been performed to prepare nanocellulose (NC) from micro-crystalline cellulose (MCC) and test their effect on the performance properties of agar-based composite films. The NC was characterized by STEM, XRD, FTIR, and TGA. The NC was well dispersed in distilled water after sonication and their size was in the range of 100-500nm. The XRD results revealed the crystallinity of NC. The crystallinity index of NC (0.71) was decreased compared to the MCC (0.81). The effect of NC or MCC content (1, 3, 5 and 10wt% based on agar) on the mechanical, water vapor permeability (WVP), and thermal properties of the composites were studied. The NC obtained from MCC can be used as a reinforcing agent for the preparation of biodegradable composites films for their potential use in the development of biodegradable food packaging materials. PMID:26453846

  6. Evaluation of Remel Spectra CRE Agar for Detection of Carbapenem-Resistant Bacteria from Rectal Swabs Obtained from Residents of a Long-Term-Care Facility

    PubMed Central

    Urban, Carl M.; Kreiswirth, Barry N.; Chen, Liang; Osorio, Giuliana; Kopacz, Joanna; Labaze, Georges; Segal-Maurer, Sorana

    2015-01-01

    We compared the Remel Spectra CRE agar plate to CDC standard methodology for the isolation of carbapenem-resistant Enterobacteriaceae (CRE) from 300 rectal swab specimens obtained from patients residing in a long-term-care facility (LTCF). Multiplex PCR experiments were performed on isolates to identify specific Klebsiella pneumoniae carbapenemases (KPC) and additional ?-lactamases. Of the 300 patients, 72 (24%) harbored CRE and were PCR positive for KPC enzymes. The Remel Spectra CRE plates detected KPC-type CRE in isolates from 70 of 72 patients (97.2%), while the CDC method detected CRE in 56 of 72 (77.8%). CRE identification results were available in 18 h compared to 36 h for the CDC method. Remel Spectra CRE agar plates can provide useful means for a fast and reliable method for detecting KPC-type CRE and for accelerated institution of appropriate infection control precautions. PMID:26085613

  7. Comparison of the Copan eSwab System with an Agar Swab Transport System for Maintenance of Fastidious Anaerobic Bacterium Viability.

    PubMed

    Tyrrell, Kerin L; Citron, Diane M; Leoncio, Eliza S; Goldstein, Ellie J C

    2016-05-01

    We compared the eSwab system to a swab with an anaerobic transport semisolid agar system for their capacities to maintain the viability of 20 species of fastidious anaerobes inoculated on the bench and held at ambient or refrigerator temperature for 24 or 48 h. On average, both systems maintained similar viabilities among analogous groups of organisms at both temperatures, although there were quantitative differences among some species. PMID:26888906

  8. Structure elucidation of auxofuran, a metabolite involved in stimulating growth of fly agaric, produced by the mycorrhiza helper bacterium Streptomyces AcH 505.

    PubMed

    Keller, Simone; Schneider, Kathrin; Süssmuth, Roderich D

    2006-12-01

    Mycorrhiza helper bacterium Streptomyces strain AcH 505 stimulates ectomycorrhiza formation between spruce and fly agaric by supporting fungal growth whereas growth of pathogenic fungi is suppressed. A fungal growth promoting substance was isolated and the chemical structure elucidated by mass spectrometry and NMR spectroscopy. The absolute configuration of the novel fungal growth promoting compound auxofuran (1) was deduced from NMR data with the help of Mosher esters. PMID:17323648

  9. Comparison of the Copan eSwab System with an Agar Swab Transport System for Maintenance of Fastidious Anaerobic Bacterium Viability

    PubMed Central

    Citron, Diane M.; Leoncio, Eliza S.; Goldstein, Ellie J. C.

    2016-01-01

    We compared the eSwab system to a swab with an anaerobic transport semisolid agar system for their capacities to maintain the viability of 20 species of fastidious anaerobes inoculated on the bench and held at ambient or refrigerator temperature for 24 or 48 h. On average, both systems maintained similar viabilities among analogous groups of organisms at both temperatures, although there were quantitative differences among some species. PMID:26888906

  10. A modified MacConkey agar for selective enumeration of necrotoxigenic E. coli O55 and probiotic E. coli Nissle 1917.

    PubMed

    Splichalova, Alla; Splichal, Igor; Sonnenborn, Ulrich; Rada, Vojtech

    2014-09-01

    An agar selective enumeration of necrotoxigenic Escherichia coli O55 (NTEC2) and probiotic E. coli Nissle 1917, using modified MacConkey agar, was developed to study bacterial interference between these E. coli strains in a gnotobiotic piglet model. Replacement of lactose with saccharose in the agar enables the direct visual enumeration of red colonies of E. coli O55 and yellow colonies of E. coli Nissle 1917 that are co-cultured in the same Petri dish. A total of 336 colonies (168 for each color) were subjected to strain-specific PCR identification with LNA probes. Sensitivity, specificity, and positive and negative predictive values were 96.43%, 95.83%, 95.86% and 96.41% respectively in E. coli O55, and 98.21%, 97.02%, 97.06% and 98.19% respectively in E. coli Nissle 1917. Color-based enumeration of both E. coli strains in colonic contents and mesenteric lymph nodes homogenates of gnotobiotic piglets demonstrated the applicability of this method for the gnotobiotic piglet model of enteric diseases. PMID:25008462

  11. Evaluation of Escherichia coli O157:H7 in apple juice with Cornus fruit (Cornus officinalis Sieb. et Zucc.) extract by conventional media and thin agar layer method.

    PubMed

    Wu, Vivian C H; Qiu, Xujian; Peggy Hsieh, Y-H

    2008-02-01

    Escherichia coli O157:H7 survival in apple juice supplemented with Cornus fruit (Cornus officinalis Sieb. et Zucc.) extract was studied. Inoculated samples with or without Cornus fruit extract were kept at 21 and 7 degrees C. Microbial analysis was conducted on days 0, 1, 3, 5, and 7. MacConkey sorbitol agar (MSA), tryptic soy agar (TSA), and thin agar layer (TAL) medium were used to compare the recovery of bacteria stressed under combination treatment. Influence of temperature, storage time, and Cornus fruit on survival of cells was evaluated. The most dramatic reduction of E. coli O157:H7 was observed in apple juice with Cornus fruit extract at 21 degrees C. At 7 degrees C, E. coli O157:H7 was reduced by 2.3logcfu/ml in the apple juice with Cornus fruit extract compared to the control sample on day 7. TAL and TSA were more efficient than MSA. Cornus fruit extract can be used in combination with temperature and storage time controls to inactivate E. coli O157:H7 in apple juice. This study has shown that TAL is a viable method of recovering and differentiating injured microorganisms and apple juice supplemented with Cornus fruit has potential as a value-added beverage with antimicrobial effects and potential health benefits. PMID:17993394

  12. Fuzzy logic color detection: Blue areas in melanoma dermoscopy images.

    PubMed

    Lingala, Mounika; Stanley, R Joe; Rader, Ryan K; Hagerty, Jason; Rabinovitz, Harold S; Oliviero, Margaret; Choudhry, Iqra; Stoecker, William V

    2014-07-01

    Fuzzy logic image analysis techniques were used to analyze three shades of blue (lavender blue, light blue, and dark blue) in dermoscopic images for melanoma detection. A logistic regression model provided up to 82.7% accuracy for melanoma discrimination for 866 images. With a support vector machines (SVM) classifier, lower accuracy was obtained for individual shades (79.9-80.1%) compared with up to 81.4% accuracy with multiple shades. All fuzzy blue logic alpha cuts scored higher than the crisp case. Fuzzy logic techniques applied to multiple shades of blue can assist in melanoma detection. These vector-based fuzzy logic techniques can be extended to other image analysis problems involving multiple colors or color shades. PMID:24786720

  13. An anion channel in Arabidopsis hypocotyls activated by blue light

    NASA Technical Reports Server (NTRS)

    Cho, M. H.; Spalding, E. P.; Evans, M. L. (Principal Investigator)

    1996-01-01

    A rapid, transient depolarization of the plasma membrane in seedling stems is one of the earliest effects of blue light detected in plants. It appears to play a role in transducing blue light into inhibition of hypocotyl (stem) elongation, and perhaps other responses. The possibility that activation of a Cl- conductance is part of the depolarization mechanism was raised previously and addressed here. By patch clamping hypocotyl cells isolated from dark-grown (etiolated) Arabidopsis seedlings, blue light was found to activate an anion channel residing at the plasma membrane. An anion-channel blocker commonly known as NPPB 15-nitro-2-(3-phenylpropylamino)-benzoic acid] potently and reversibly blocked this anion channel. NPPB also blocked the blue-light-induced depolarization in vivo and decreased the inhibitory effect of blue light on hypocotyl elongation. These results indicate that activation of this anion channel plays a role in transducing blue light into growth inhibition.

  14. Blue LEDs feasibility for tissue fluorescence analysis

    NASA Astrophysics Data System (ADS)

    Dets, Sergiy M.; Denisov, Nikolay A.

    2000-04-01

    We considered the limited number of light-induced fluorescence applications for marketed ultra-bright blue LEDs where they can compete with versatile laser sources. Satisfactory optical output and miniature size as well as low power consumption of blue LEDs emitting at 470 nm allow to consider them as a promising alternatives to metal vapor or gas lasers used in many expires LIF applications. Available to authors LEDs form Hewlett-Packard, Micro Electronics Corp., Nichia Chemical Industries Ltd. and Toyoda Gosei Co. were tested to comply with demands to a tissue excitation source for portable spectroscopes. The optical performance of LEDs has shown that selected group of InGaN LEDs could be successfully used for that. The miniature illuminator that includes LED, focusing condenser, filter set and distal fiberoptic light concentrator was designed and tested in conjunction with portable CCD- equipped spectroscope. Operating in dark condition the proposed LED illuminator provides the level of fluorescence signal sufficient to detect spectral abnormalities in human Caucasian skin and excised gastrointestinal samples. All tissue autofluorescence data taken under LED illumination were compared with readings under He-Cd laser excitation and showed a good match. A new diagnostic designs based on LEDs were considered for clinical use.

  15. Strategic blue-green communication filters

    NASA Astrophysics Data System (ADS)

    Rosenberg, W. J.

    1984-04-01

    The project began as an effort to construct narrowband, wide-field-of-view, large-aperture, plastic, birefringent filters suitable for blue-green communications. During the course of the study we investigated the use of crystalline materials in addition to plastic films, and we studied filter design theory in order to find designs more suitable to the blue-green system requirements. In addition, we constructed a quartz, 2A filter for the 1981 SLCAIR experiment. In this report we have included an introduction to the principles of narrowband, wide-field-of-view, birefringent filters. This section is included since the subject matter is not readily available except piecemeal in technical journals. Section 3 is a discussion of the materials which were considered during this study. It contains subsections devoted to crystals, plastics and analog element, respectively. A class of new lossless filter designs is described in Section 4. These designs are expected to provide a basis for high-transmission filters in the future. The operational SLCAIR-81 filter is described in Section 5. It was part of the successful experiment which demonstrated communication to the USN Dolphin, a research submarine. Finally, in Section 6 we describe the non-vignetting filter design which was discovered during this study. It represents a significant throughput advantage for crystal filters used in non-imaging applications.

  16. Pulsations and outbursts of luminous blue variables

    SciTech Connect

    Cox, A.N.; Guzik, J.A.; Soukup, M.S.; Despain, K.M.

    1997-06-01

    We propose an outburst mechanism for the most luminous stars in our and other galaxies. These million solar luminosity stars, with masses (after earlier mass loss) of between 20 and maybe 70 solar masses, are pulsationally unstable for both radial and low-degree nonradial modes. Some of these modes are ``strange,`` meaning mostly that the pulsations are concentrated near the stellar surface and have very rapid growth rates in linear theory. The pulsation driving is by both the high iron line opacity (near 150,000 K) and the helium opacity (near 30,000 K) kappa effects. Periods range from 5 to 40 days. Depending on the composition, pulsations periodically produce luminosities above the Eddington limit for deep layers. The radiative luminosity creates an outward push that readily eases the very low gamma envelope to very large outburst radii. A key point is that a super-Eddington luminosity cannot be taken up by the sluggish convection rapidly enough to prevent an outward acceleration of much of the envelope. As the helium abundance in the envelope stellar material increases by ordinary wind mass loss and the luminous blue variable outbursts, the opacity in the deep pulsation driving layers decreases. This makes the current Eddington luminosity even higher so that pulsations can then no longer give radiative luminosities exceeding the limit. For the lower mass and luminosity luminous blue variables there is considerably less iron line opacity driving, and pulsations are almost all caused by the helium ionization kappa effect.

  17. Host materials for blue phosphorescent OLEDs

    NASA Astrophysics Data System (ADS)

    Wagner, Daniel; Rothmann, Michael; Strohriegl, Peter; Lennartz, Christian; Münster, Ingo; Wagenblast, Gerhard; Schildknecht, Christian

    2012-09-01

    PCTrz, a new bipolar host material containing a phenoxy-carbazole separated from a biscarbazolyl-triazine by a non-conjugated ether bond is presented. Computational calculations demonstrated the separation of PCTrz into an oxidation and a reduction site. A phosphorescent OLED with PCTrz as host and FIrpic as blue emitter yielded high current efficiencies of up to 16.2 cd/A. Additionally two electron transporting host materials DBFTaz and DBFTazC, both containing 1,2,4-triazole moieies, were synthesized and characterized. The triazole moiety in DBFTaz was formed by a classical ring closure reaction between a N-benzoylbenzimidate and a hydrazine. For DBFTazC we used another synthetical pathway which involves subsequent coupling of a carbazole and a triazole moiety to a dibenzofuran core. Both triazoles posses high triplet energies of 2.95 eV for DBFTaz and 2.97 eV for DBFTazC, which make the compounds interesting as matrix materials for blue phosphorescent OLEDs.

  18. Differential migration of Blue Grouse in Colorado

    USGS Publications Warehouse

    Cade, Brian S.; Hoffman, Richard W.

    1993-01-01

    We examined migration of adult Blue Grouse (Dendragapus obscurus) in north-central Colorado by radio tracking 13 males and 19 females. Elevational changes associated with movements to winter areas were greater for males (median = 488 m, range = 183-671 m) than females (median = 122 m, range = -61-760 m). Males (median = 10.5 km, range = 1.0-29.4 km) also moved farther than females (median = 1.0 km, range = 0.1-28.0 km), resulting in partial segregation of sexes during winter. Directional orientation of movements to wintering areas was nonrandom for long-distance (>3 km) migrants. Median elevational change (122 m) and distance (0.6 km) between the first-winter and first-breeding areas for seven juvenile females were similar to movements of adult females. Males (median = 7 July) departed breeding areas earlier than females (median = 11 August), but arrived (median = 14 October) on winter areas about the same time as females (median = 23 October). Both sexes exhibited fidelity to winter areas. The average distance between winter locations ranged from 94 to 312 m (median = 135 m) for 11 radio-marked adults, suggesting Blue Grouse were sedentary on their winter ranges.

  19. Maya blue: a clay-organic pigment?

    PubMed

    Van Olphen, H

    1966-11-01

    Maya Blue, a pigment used by the Mayas in Yucatan, is remarkably stable: the color is not destroyed by hot concentrated mineral acids or by heating to about 250 degrees C. The principal constituent is the colorless mineral attapulgite. It is proposed that the pigment is an adsorption complex of attapulgite and natural indigo; a synthetic equivalent may be prepared from attapulgite and either indoxylester or indigo, or by applying the vat-dyeing technique, with reduced indigo.The low dye content of the pigment (less than 0.5 percent) indicates that the dye is absorbed only on the external surfaces of the attapulgite particles and not throughout the channels in their structures. The complex as such is not stable to acids, but the stability displayed by Maya Blue is achieved simply by heating the complex to from 75 degrees to 150 degrees C for several days. An analogous stable pigment can be prepared from sepiolite and indigo. No stable pigments could be prepared from clays with platelike structures or from zeolites. PMID:17778806

  20. Raphael Meldola, his blue and his times.

    PubMed

    Travis, A S

    2012-05-01

    Raphael Meldola (1849-1915), English industrial and academic chemist, spectroscopist, naturalist, educator and lobbyist for science, is today almost a forgotten scientist whose life is celebrated only with a medal awarded by the Royal Society of Chemistry that honors achievement by younger chemists. In the 1870-80s, however, he invented a number of important synthetic dyestuffs including the cotton dyes isamine blue and Meldola's blue, and also naphthol green B, all of which have had application in biology and medicine. I describe here the early emergence of the synthetic dye industry, the first science-based industry, Meldola's role in its development, and his own inventions. Meldola's wide ranging achievements in science led to appointments as president of important professional scientific and manufacturers' societies. He was a fervent disciple of natural selection, a correspondent of Charles Darwin, and a prominent 19(th)-century neo-Darwinian. In 1886, drawing on analogies with evolutionary theory, he warned the British that neglect of science, particularly chemistry, would lead to industrial decline and even extinction, though his message generally was ignored, at least until 1914. PMID:22148999

  1. The Return of the Blue Butterfly

    NASA Astrophysics Data System (ADS)

    Santos, Anabela

    2014-05-01

    The Return of the Blue Butterfly The English writer Charles Dickens once wrote: "I only ask to be free. The butterflies are free". But are they really? The work that I performed with a group of students from 8th grade, had a starting point of climate change and the implications it has on ecosystems. Joining the passion I have for butterflies, I realized that they are also in danger of extinction due to these climatic effects. Thus, it was easy to seduce my students wanting to know more. Luckily I found Dr. Paula Seixas Arnaldo, a researcher at the University of Trás-os-Montes and Alto Douro, who has worked on butterflies and precisely investigated this issue. Portugal is the southern limit of butterfly-blue (Phengaris alcon), and has been many years in the red book of endangered species. Butterfly-blue is very demanding of their habitat, and disappears very easily if ideal conditions are not satisfied. Increased fragmentation of landscapes and degradation of suitable habitats, are considered the greatest challenges of the conservation of Phengaris butterfly in Portugal. In recent decades, climate change has also changed butterfly-blue spatial distribution with a movement of the species northward to colder locations, and dispersion in latitude. Butterflies of Europe must escape to the North because of the heat. Dr. Paula Seixas Arnaldo and her research team began a project, completed in December 2013, wanted to preserve and restore priority habitats recognized by the European Union to help species in danger of disappearing with increasing temperature. The blue butterfly is extremely important because it is a key indicator of the quality of these habitats. In the field, the butterflies are monitored to collect all possible data in order to identify the key species. Butterflies start flying in early July and cease in late August. Mating takes about an hour and occurs in the first days of life. The gentian-peat (Gentiana pneumonanthe) serves as the host plant for laying eggs. Each female lays an average of 60 eggs. Larva must grow in a plant near an anthill of Myrmica aloba species. This is important because butterfly larvae are myrmecophilous, living with ants that feed the butterfly larvae for 11 months, because the ants think the butterfly larvae are ant larvae. In early summer the larvae pupate in the nest of ants. Before expanding their wings, they have to leave quickly to avoid being killed by ants when the ants discover have been deceived. My students became aware of this research; we studied and prepared in order to carry out fieldwork. Thus students learn the content and curricular in a scientifically fun way, first with group work in the classroom with my guidance and in a second stage carry knowledge to the field under the guidance of Dra Paula Seixas Arnaldo. We know where we started ... where we arrives is success!

  2. Bounceback: Blues thrive as markets cool toward HMOs.

    PubMed

    Cunningham, Robert; Sherlock, Douglas B

    2002-01-01

    Enrollment in Blue Cross and Blue Shield (BCBS) plans has grown by almost seventeen million since 1994, and recent financial performance indicators are positive for most plans in the Blues system. These gains have been achieved by for-profit, nonprofit, and mutually owned plans. A journalistic analysis of distinctive features contributing to recent successes is offered, combining observations of financial analysts, health services researchers, and BCBS officials. Long-term stability, broad provider networks, and conservative financial management have given the Blues advantages vis-à-vis many managed care organizations that have lost market share in the same period. PMID:11900082

  3. Jupiter in blue, ultraviolet and near infrared

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These three images of Jupiter, taken through the narrow angle camera of NASA's Cassini spacecraft from a distance of 77.6 million kilometers (48.2 million miles) on October 8, reveal more than is apparent to the naked eye through a telescope.

    The image on the left was taken through the blue filter. The one in the middle was taken in the ultraviolet. The one on the right was taken in the near infrared.

    The blue-light filter is within the part of the electromagnetic spectrum detectable by the human eye. The appearance of Jupiter in this image is, consequently, very familiar. The Great Red Spot (below and to the right of center) and the planet's well-known banded cloud lanes are obvious. The brighter bands of clouds are called zones and are probably composed of ammonia ice particles. The darker bands are called belts and are made dark by particles of unknown composition intermixed with the ammonia ice.

    Jupiter's appearance changes dramatically in the ultraviolet and near infrared images. These images are near negatives of each other and illustrate the way in which observations in different wavelength regions can reveal different physical regimes on the planet.

    All gases scatter sunlight efficiently at short wavelengths; this is why the sky appears blue on Earth. The effect is even more pronounced in the ultraviolet. The gases in Jupiter's atmosphere, above the clouds, are no different. They scatter strongly in the ultraviolet, making the deep banded cloud layers invisible in the middle image. Only the very high altitude haze appears dark against the bright background. The contrast is reversed in the near infrared, where methane gas, abundant on Jupiter but not on Earth, is strongly absorbing and therefore appears dark. Again the deep clouds are invisible, but now the high altitude haze appears relatively bright against the dark background. High altitude haze is seen over the poles and the equator.

    The Great Red Spot, prominent in all images, is obviously a feature whose influence extends high in the atmosphere. As the Cassini cameras continue to return images of Jupiter, it will be possible to construct a three-dimensional picture of how clouds form and evolve by watching the changing appearance of Jupiter in different spectral regions.

    JPL manages the Cassini mission for NASA's Office of Space Science, Washington, D.C. JPl is a division of the California Institute of Technology in Pasadena.

  4. Violet and blue light blocking intraocular lenses: photoprotection versus photoreception

    PubMed Central

    Mainster, M A

    2006-01-01

    Aim To analyse how intraocular lens (IOL) chromophores affect retinal photoprotection and the sensitivity of scotopic vision, melanopsin photoreception, and melatonin suppression. Methods Transmittance spectra of IOLs, high pass spectral filters, human crystalline lenses, and sunglasses are used with spectral data for acute ultraviolet (UV)‐blue photic retinopathy (“blue light hazard” phototoxicity), aphakic scotopic luminous efficiency, melanopsin sensitivity, and melatonin suppression to compute the effect of spectral filters on retinal photoprotection, scotopic sensitivity, and circadian photoentrainment. Results Retinal photoprotection increases and photoreception decreases as high pass filters progressively attenuate additional short wavelength light. Violet blocking IOLs reduce retinal exposure to UV (200–400 nm) radiation and violet (400–440 nm) light. Blue blocking IOLs attenuate blue (440–500 nm) and shorter wavelength optical radiation. Blue blocking IOLs theoretically provide better photoprotection but worse photoreception than conventional UV only blocking IOLs. Violet blocking IOLs offer similar UV‐blue photoprotection but better scotopic and melanopsin photoreception than blue blocking IOLs. Sunglasses provide roughly 50% more UV‐blue photoprotection than either violet or blue blocking IOLs. Conclusions Action spectra for most retinal photosensitisers increase or peak in the violet part of the spectrum. Melanopsin, melatonin suppression, and rhodopsin sensitivities are all maximal in the blue part of the spectrum. Scotopic sensitivity and circadian photoentrainment decline with ageing. UV blocking IOLs provide older adults with the best possible rhodopsin and melanopsin sensitivity. Blue and violet blocking IOLs provide less photoprotection than middle aged crystalline lenses, which do not prevent age related macular degeneration (AMD). Thus, pseudophakes should wear sunglasses in bright environments if the unproved phototoxicity‐AMD hypothesis is valid. PMID:16714268

  5. Blue Light Protects Against Temporal Frequency Sensitive Refractive Changes

    PubMed Central

    Rucker, Frances; Britton, Stephanie; Spatcher, Molly; Hanowsky, Stephan

    2015-01-01

    Purpose Time spent outdoors is protective against myopia. The outdoors allows exposure to short-wavelength (blue light) rich sunlight, while indoor illuminants can be deficient at short-wavelengths. In the current experiment, we investigate the role of blue light, and temporal sensitivity, in the emmetropization response. Methods Five-day-old chicks were exposed to sinusoidal luminance modulation of white light (with blue; N = 82) or yellow light (without blue; N = 83) at 80% contrast, at one of six temporal frequencies: 0, 0.2, 1, 2, 5, 10 Hz daily for 3 days. Mean illumination was 680 lux. Changes in ocular components and corneal curvature were measured. Results Refraction, eye length, and choroidal changes were dependent on the presence of blue light (P < 0.03, all) and on temporal frequency (P < 0.03, all). In the presence of blue light, refraction did not change across frequencies (mean change −0.24 [diopters] D), while in the absence of blue light, we observed a hyperopic shift (>1 D) at high frequencies, and a myopic shift (>−0.6 D) at low frequencies. With blue light there was little difference in eye growth across frequencies (77 μm), while in the absence of blue light, eyes grew more at low temporal frequencies and less at high temporal frequencies (10 vs. 0.2 Hz: 145 μm; P < 0.003). Overall, neonatal astigmatism was reduced with blue light. Conclusions Illuminants rich in blue light can protect against myopic eye growth when the eye is exposed to slow changes in luminance contrast as might occur with near work. PMID:26393671

  6. FIrpic: archetypal blue phosphorescent emitter for electroluminescence.

    PubMed

    Baranoff, Etienne; Curchod, Basile F E

    2015-05-14

    FIrpic is the most investigated bis-cyclometallated iridium complex in particular in the context of organic light emitting diodes (OLEDs) because of its attractive sky-blue emission, high emission efficiency, and suitable energy levels. In this Perspective we review the synthesis, structural characterisations, and key properties of this emitter. We also survey the theoretical studies and summarise a series of selected monochromatic electroluminescent devices using FIrpic as the emitting dopant. Finally we highlight important shortcomings of FIrpic as an emitter for OLEDs. Despite the large body of work dedicated to this material, it is manifest that the understanding of photophysical and electrochemical processes are only broadly understood mainly because of the different environment in which these properties are measured, i.e., isolated molecules in solvent vs. device. PMID:25388935

  7. CO 2 entrapment in natural ultramarine blue

    NASA Astrophysics Data System (ADS)

    Miliani, Costanza; Daveri, Alessia; Brunetti, Brunetto Giovanni; Sgamellotti, Antonio

    2008-12-01

    Ultramarine blue pigments (in the form of highly concentrated KBr discs) have been examined by transmission infrared spectroscopy. Evidence of entrapment of carbon dioxide in the natural pigment from Afghanistan was indicated by the absorption band at 2340 cm -1 and a low frequency satellite corresponding to the 13CO 2 isotopologue. The thermal behavior of natural ultramarine, has been studied by FTIR, UV-vis spectroscopy, and XRD, from 300 K to 1120 K. Measurements show that CO 2 and the encapsulated S3- chromophore behave in the same way during the heating experiment, starting to be released only at about 670 K when the apertures of the sodalite β-cages became larger as an effect of temperature.

  8. Methylene Blue: Magic Bullet for Vasoplegia?

    PubMed

    Hosseinian, Leila; Weiner, Menachem; Levin, Matthew A; Fischer, Gregory W

    2016-01-01

    Methylene blue (MB) has received much attention in the perioperative and critical care literature because of its ability to antagonize the profound vasodilation seen in distributive (also referred to as vasodilatory or vasoplegic) shock states. This review will discuss the pharmacologic properties of MB and review the critical care, liver transplantation, and cardiac anesthesia literature with respect to the efficacy and safety of MB for the treatment of shock. Although improved blood pressure has consistently been demonstrated with the use of MB in small trials and case reports, better oxygen delivery or decreased mortality with MB use has not been demonstrated. Large randomized controlled trials are still necessary to identify the role of MB in hemodynamic resuscitation of the critically ill. PMID:26678471

  9. Blue Skies Research and the global economy

    NASA Astrophysics Data System (ADS)

    Braben, Donald W.

    2002-11-01

    Robert Solow's seminal work of the 1950s showed that science and technology are major sources of long-term global economic growth. But we have recently changed the ways that science and technology are managed. Industrial and academic research once thrived on individual freedom and flair. Progressively for the past three decades or so, however, research has been focused on short-term objectives selected by consensus. Global per-capita growth has steadily declined. Scientific enterprise is losing diversity. Blue Skies Research can help to restore diversity and to create the new technologies that can stimulate growth, but funding agencies nowadays rarely allow total freedom. A new coefficient of adventurousness is described. Its use, or other means, may help restore economic growth to its former levels.

  10. Rapid coomassie blue staining of protein gels.

    PubMed

    Simpson, Richard J

    2010-04-01

    Coomassie brilliant blue R250 (CBR-250) and silver staining are the most widely used methods for the routine visualization of proteins separated by SDS-PAGE. CBR-250 is an organic dye that complexes with basic amino acids, such as arginine, lysine, and histidine, as well as tyrosine. Conventional CBR-250 staining is capable of detecting as little as 30-100 ng of protein, but sensitivity can be improved by performing the staining and destaining at elevated temperatures. The method described in this protocol, which is a modified version of the conventional Coomassie protocol, speeds up the destaining process for faster results with increased sensitivity and is compatible with mass-spectrometry-based methods for identifying proteins. PMID:20360367

  11. Approaches toward a blue semiconductor laser

    NASA Technical Reports Server (NTRS)

    Ladany, I.

    1989-01-01

    Possible approaches for obtaining semiconductor diode laser action in the blue region of the spectrum are surveyed. A discussion of diode lasers is included along with a review of the current status of visible emitters, presently limited to 670 nm. Methods are discussed for shifting laser emission toward shorter wavelengths, including the use of II-IV materials, the increase in the bandgap of III-V materials by addition of nitrogen, and changing the bandstructure from indirect to direct by incorporating interstitial atoms or by constructing superlattices. Non-pn-junction injection methods are surveyed, including avalanche breakdown, Langmuir-Blodgett diodes, heterostructures, carrier accumulation, and Berglund diodes. Prospects of inventing new multinary semiconducting materials are discussed, and a number of novel materials described in the literature are tabulated. New approaches available through the development of quantum wells and superlattices are described, including resonant tunneling and the synthesis of arbitrary bandgap materials through multiple quantum wells.

  12. Ultrasound promoted synthesis of Nile Blue derivatives.

    PubMed

    Raju, B Rama; Sampaio, Diogo M F; Silva, M M; Coutinho, Paulo J G; Gonçalves, M Sameiro T

    2014-01-01

    Ultrasound irradiation was used for the first time towards the synthesis of new Nile Blue related benzo[a]phenoxazinium chlorides possessing isopentylamino, (2-cyclohexylethyl)amino and phenethylamino groups at 5-position of the heterocyclic system. The efficacy of sonochemistry was investigated with some of our earlier reported synthesis of benzo[a]phenoxazinium chlorides. This newer protocol proved competent in terms of reaction times and enhanced yields. Photophysical studies carried out in ethanol, water and simulated physiological conditions, revealed that emission maxima occurred in the range 644-656 nm, with high fluorescent quantum yields. Other attractive feature exhibited by these materials includes good thermal stability. These properties might be useful in the development of fluorescent probes for biotechnology. PMID:23769749

  13. Identification of human megakaryocytes with rhodanile blue.

    PubMed

    Kass, L

    1985-04-01

    Using the oxazine dye rhodanile blue, large typical megakaryocytes and small megakaryocytes (micromegakaryocytes) from the bone marrows of normal persons, and from patients with a variety of preleukemic disorders, acute lymphoblastic and nonlymphoblastic leukemia, chronic granulocytic leukemia, and idiopathic thrombocytopenic purpura as an example of nonmalignant but abnormal megakaryocytopoiesis, showed intense pink staining of the cytoplasm. This pink metachromasia was not obliterated by prior digestion with either diastase or ribonuclease, but was markedly diminished or obliterated by preincubation with hyaluronidase, suggesting that the stain may detect a high content of acid mucopolysaccharides in megakaryocytes. Since the stain is simple, direct, and reproducible, it may represent a useful addition to the cytochemistry of megakaryocytes and complement the more complex immunologic techniques available currently. PMID:2580502

  14. Image vectorization using blue-noise sampling

    NASA Astrophysics Data System (ADS)

    Zhao, Jiaojiao; Feng, Jie; Zhou, Bingfeng

    2013-03-01

    Current image vectorization techniques mainly deal with images with simple and plain colors. For full-color photographs, many difficulties still exist in object segmentation, feature line extraction, and color distribution reconstruction, etc. In this paper, we propose a high-efficiency image vectorization method based on importance sampling and triangulation. A set of blue-noise sampling points is first generated on the image plane by an improved error-diffusion sampling method. The point set well preserves the features in the image. Then after triangulation on this point set, color information can be recorded on the mesh vertices to form a vector image. After certain image editing, e.g. scaling or transforming, the whole image can be reconstructed by color interpolating inside each triangle. Experiments show that the method has high performing efficiency and abilities in feature-preserving. It will bring benefits to many applications, e.g. image compressing, editing, transmitting and resolution enhancement.

  15. Big Blue Transgenic Mouse lacl mutation analysis

    SciTech Connect

    Stiegler, G.L.; Stillwell, L.C. )

    1993-01-01

    In this report the authors describe a rapid general method for mutant blue plaque molecular analysis. The mutant analysis discussed here resulted from radon inhalation exposure. The described method circumvents Stratagene's plasmid isolation and ensuing sequence analysis of the entire lac1 gene. The authors have adapted the polymerase chain reaction (PCR) method and single-strand conformation polymorphism (SSCP) analysis for localizing mutations within the lac1 coding region. Three overlapping PCR products of approximately 450 bp representing the entire lac1 coding region are used for SSCP analysis. Those PCR products with an altered SSCP electrophoretic migration focus the mutation to a smaller region of the lac1 gene that is analyzed by direct cycle sequencing. 5 refs., 1 fig.

  16. Retrofitting outlet tunnel for Blue River Project

    SciTech Connect

    Shen, Y.Y.; Stow, J.A.; Edmister, T.D.

    1995-12-31

    The major development of the Blue River Project is to use the existing tunnel to supply water to a penstock and turbine located in a proposed powerhouse. The flood release through the tunnel is presently discharged by open channel flow. After the modification, the outlet and a new gate structure will be pressurized to allow combined usage of hydropower and flood release. The velocity through the new gate will increase by almost 70 percent. A complex transition was designed to house the bifurcation to penstock and to the new dual gate structure. A comprehensive physical model study was conducted to examine the effectiveness of the transition. Turbulent pressure fluctuation tests and analyses were performed from upstream of the bifurcation through the new gates. A revised transition was designed to minimize any potential pressure fluctuation and cavitation problems.

  17. Blue Marble: Remote Characterization of Habitable Planets

    NASA Technical Reports Server (NTRS)

    Woolf, Neville; Lewis, Brian; Chartres, James; Genova, Anthony

    2009-01-01

    The study of the nature and distribution of habitable environments beyond the Solar System is a key area for Astrobiology research. At the present time, our Earth is the only habitable planet that can be characterized in the same way that we might characterize planets beyond the Solar System. Due to limitations in our current and near-future technology, it is likely that extra-solar planets will be observed as single-pixel objects. To understand this data, we must develop skills in analyzing and interpreting the radiation obtained from a single pixel. These skills must include the study of the time variation of the radiation, and the range of its photometric, spectroscopic and polarimetric properties. In addition, to understand whether we are properly analyzing the single pixel data, we need to compare it with a ground truth of modest resolution images in key spectral bands. This paper discusses the concept for a mission called Blue Marble that would obtain data of the Earth using a combination of spectropolarimetry, spectrophotometry, and selected band imaging. To obtain imagery of the proper resolution, it is desirable to place the Blue Marble spacecraft no closer than the outer region of cis-lunar space. This paper explores a conceptual mission design that takes advantage of low-cost launchers, bus designs and mission elements to provide a cost effective observing platform located at one of the stable Earth-moon Lagrangian points (L4, L5). The mission design allows for the development and use of novel technologies, such as a spinning moon sensor for attitude control, and leverages lessons-learned from previous low-cost spacecraft such as Lunar Prospector to yield a low-risk mission concept.

  18. Photophysical properties of blue - emitting silicon nanoparticles.

    PubMed

    Portolés, Manuel J Llansola; Nieto, Felipe Rodriguez; Soria, Delia B; Amalvy, Javier I; Peruzzo, Pablo J; Mártire, Daniel O; Kotler, Mónica; Holub, Oliver; Gonzalez, Mónica C

    2009-08-01

    Silicon nanoparticles with strong blue photoluminescence were synthesized by electrochemical etching of silicon wafers and ultrasonically removed under N(2) atmosphere in organic solvents to produce colloids. Thermal treatment leads to the formation of colloidal Si particles of 3 ± 1 nm diameter, which upon excitation with 340 - 380 nm light exhibited room temperature luminescence in the range from 400 to 500 nm. The emission and the one- and two-photon excitation spectra of the particles are not sensitive to surface functionalization with methyl 2-methylprop-2-enoate. However, the derivatized particles show higher emission quantum yields in air-saturated suspensions (44%) than the underivatized particles (27%), as well as higher stability of its dispersions.FTIR and XPS spectra indicate a significant surface oxidation of the particles. The Si:O:C ratio at the surface of the derivatized particles estimated from XPS is Si(3)O(6)(C(5)O(2)H(y))(1), with y = 7 - 8. Vibronic spacing is observed in both the emission and excitation spectra. The information obtained from one-photon excitation experiments (emission and excitation spectra, photoluminescence quantum yields, luminescence decay lifetimes and anisotropy correlation lifetimes), as well as from two-photon excitation fluorescence correlation spectroscopy (brightness and diffusion coefficients) and TEM indicate that the blue-emitting particles are monodisperse and ball-shaped. Particle size clearly determines the emission and excitation spectral region, as expected from quantum confinement, but the presence and extent of Si-O species on the silicon networks seem crucial for determining the spectrum features and intensity of emission. The nanoparticles could hold great potential as quantum dots for applications as luminescence sensors in biology and environmental science. PMID:22866180

  19. Lethal effect of blue light-activated hydrogen peroxide, curcumin and erythrosine as potential oral photosensitizers on the viability of Porphyromonas gingivalis and Fusobacterium nucleatum

    PubMed Central

    Habiboallh, Ghanbari; Mahbobeh, Naderi Nasab; Mina, Zareian Jahromi; Majid, Zakeri; Nooshin, Arjmand

    2015-01-01

    Objectives: Recently, photodynamic therapy (PDT) has been introduced as a new modality in oral bacterial decontamination. Current research aims to evaluate the effect of photodynamic killing of visible blue light in the presence of hydrogen peroxide, curcumin and erythrosine as potential oral photosensitizers on Porphyromonas gingivalis associated with periodontal bone loss and Fusobacterium nucleatum associated with soft tissue inflammation. Materials and methods: Standard suspension of P. gingivalis and F. nucleatum were exposed to Light Emitting Diode (LED) (440–480 nm) in combination with erythrosine (22 µm), curcumin (60 µM) and hydrogen peroxide (0.3 mM) for 5 min. Bacterial samples from each treatment groups (radiation-only group, photosensitizer-only group and blue light-activated photosensitizer group) were subcultured onto the surface of agar plates. Survival of these bacteria was determined by counting the number of colony forming units (CFU) after incubation. Results: Results for antibacterial assays on P. gingivalis confirmed that curcumin, Hydrogen peroxide and erythrosine alone exerted a moderate bactericidal effect which enhanced noticeably in conjugation with visible light. The survival rate of P. gingivalis reached zero present when the suspension exposed to blue light-activated curcumin and hydrogen peroxide for 2 min. Besides, curcumin exerted a remarkable antibacterial activity against F. nucleatum in comparison with erythrosine and hydrogen peroxide (P=0.00). Furthermore, the bactericidal effect of visible light alone on P. gingivalis as black-pigmented bacteria was significant. Conclusion: Our result suggested that visible blue light in the presence of erythrosine, curcumin and hydrogen peroxide would be consider as a potential approach of PDT to kill the main gramnegative periodontal pathogens. From a clinical standpoint, this regimen could be established as an additional minimally invasive antibacterial treatment of plaque induced periodontal pathologies. PMID:26246690

  20. Is a diagnostic system based exclusively on agar gel immunodiffusion adequate for controlling the spread of equine infectious anaemia?

    PubMed

    Scicluna, Maria Teresa; Issel, Charles J; Cook, Frank R; Manna, Giuseppe; Cersini, Antonella; Rosone, Francesca; Frontoso, Raffaele; Caprioli, Andrea; Antognetti, Valeria; Antonetti, Valeria; Autorino, Gian Luca

    2013-07-26

    To improve the efficiency of the National equine infectious anaemia (EIA) surveillance program in Italy, a three-tiered diagnostic system has been adopted. This procedure involves initial screening by ELISA (Tier 1) with test-positive samples confirmed by the agar gel immunodiffusion test (AGIDT) (Tier 2) and, in the case of ELISA positive/AGIDT negative results, final determination by immunoblot (IB) (Tier 3). During this evaluation, 74,880 samples, principally collected from two Regions of Central Italy (Latium and Abruzzo) were examined, with 44 identified as negative in AGIDT but positive in both ELISA and IB. As the majority of these reactions occurred in mules, an observational study was conducted in this hybrid equid species to investigate if there is a correlation between plasma-associated viral loads and serological reactivity, to test the hypothesis that false-negative or very weak positive AGIDT results are associated with elite control of EIA virus (EIAV) replication accompanied by reduced transmission risks. The study animals consisted of 5 mules with positive AGIDT readings, along with another 5 giving negative or very weak positive results in this test. All mules were seropositive in Elisa and IB. Samples were collected routinely during an initial 56-day observation period, prior to dexamethasone treatment lasting 10 days, to determine the effect of immune suppression (IS) on clinical, humoral and virological responses. All mules were monitored for a further 28 days from day 0 of IS. None of the animals experienced relevant clinical responses before IS and there were no significant changes in antibody levels in ELISA, IB or AGIDT. However, plasma-associated viral-RNA (vRNA) loads, as determined using TaqMan(®) based RT-PCR, showed unexpectedly high sample to sample variation in all mules, demonstrating host-mediated control of viral replication is not constant over time. Furthermore, there was no apparent correlation between vRNA loads and antibody reactivity in serological tests. Analysis of PCR products established all mules were infected with viruses possessing nucleotide sequence similarity, varying from 77 to 96%, to previously identified European EIAV strains. Following IS, all mules showed increases in plasma-associated vRNA loads, suggesting control of EIAV replication is mediated by immune responses in this hybrid species. However, only three mules showed anamnestic humoral responses to rises in viral loads, as defined by at least a four-fold increase in ELISA titre, while two remained AGIDT-negative. This study demonstrates that viral loads in equids with consistent ELISA/IB positive-AGIDT negative to very weak positive test results (Group N) can be equivalent to those that produce clearly positive results in all three serologic tests (Group P). Therefore, such animals do not pose inherently lower risks for the transmission of EIAV. Consequently, the exclusive use of the AGIDT, as prescribed by the World Organization of Animal Health (OIE) for diagnosis of EIA prior to the international movement of horses, can report as negative some EIAV-infected equids. These results dramatically underscore the necessity of combining the specificity of AGIDT with tests with higher sensitivity, such as the ELISA and the power of the IB to enhance the accuracy of EIA diagnosis. PMID:23618837

  1. 77 FR 68117 - Blue Summit Wind, LLC; Notice of Petition for Declaratory Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-15

    ... Energy Regulatory Commission Blue Summit Wind, LLC; Notice of Petition for Declaratory Order Take notice... (Commission) Rules of Practice and Procedure 18 CFR 385.207(a)(2), Blue Summit Wind, LLC (Blue Summit) filed a...) interconnection facilities that deliver power from the Blue Summit's wind energy generator (Blue Summit...

  2. BLUE JOINT WILDERNESS STUDY AREA, MONTANA, AND BLUE JOINT ROADLESS AREA, IDAHO.

    USGS Publications Warehouse

    Lund, Karen; Benham, John R.

    1984-01-01

    During field studies of the Blue Joint Wilderness Study Area, Montana, and the Blue Joint Roadless Area, Idaho, areas of substantiated resource potential for epithermal precious-metal vein deposits were identified in areas of hydrothermal alteration and fossil hot springs activity in the Eocene volcanic rocks. Areas with substantiated resource potential for cobalt, copper, silver, and barite resources of the sediment-hosted type were identified in the Proterozoic quartz schist of the eastern part of the area. Probable potential exists for molybdenum in a prophyry system; anomalously high molybdenum values are coincident with high values for precious and base metals and uranium in some places. The geologic terrane precludes the occurrence of fossil fuel resources.

  3. 76 FR 35909 - Temporary Concession Contract for Blue Ridge Parkway

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... National Park Service Temporary Concession Contract for Blue Ridge Parkway AGENCY: National Park Service, Interior. ACTION: Notice of proposed award of temporary concession contracts for Blue Ridge Parkway, NC/VA...) proposes to award temporary concession contracts for the conduct of certain visitor services within...

  4. Pluto’s Blue Haze - Duration: 88 seconds.

    NASA Video Gallery

    The sky on Pluto is blue! Kind of. This is Pluto in an Minute. So it’s not exactly the case that the sky on Pluto is blue, rather, what the New Horizons science team has found in recent images do...

  5. 36 CFR 7.34 - Blue Ridge Parkway.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Blue Ridge Parkway. 7.34 Section 7.34 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.34 Blue Ridge Parkway. (a) Snowmobiles. After consideration of any special situations,...

  6. 36 CFR 7.34 - Blue Ridge Parkway.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Blue Ridge Parkway. 7.34 Section 7.34 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.34 Blue Ridge Parkway. (a) Snowmobiles. After consideration of any special situations,...

  7. OBSTACLES TO BLUE-COLLAR PARTICIPATION IN ADULT EDUCATION.

    ERIC Educational Resources Information Center

    LONDON, JACK; WENKERT, ROBERT

    WITH THE INCREASING LEISURE TIME OF BLUE-COLLAR WORKERS, CONCERN IS GROWING OVER THEIR LOW PARTICIPATION IN ADULT EDUCATION PROGRAMS. MYTHS ABOUT BLUE-COLLAR WORKERS WHICH STAND IN THEIR WAY INCLUDE--LOWER CLASS APATHY, INCAPABILITY OF SUSTAINED INTELLECTUAL EFFORT, AND LACK OF APPRECIATION OF THE VALUE OF EDUCATION. OBSTACLES INHERING IN SOCIAL…

  8. Blue Jays Win! Crows Go Down in Defeat.

    ERIC Educational Resources Information Center

    Wuthrick, Marjorie A.

    1990-01-01

    Teachers tend to teach children in different reading groups in qualitatively different ways. Crows (slower readers) work on phonics in isolation twice as often as more accomplished Blue Jays and spend much less time on reading silently or in context. Since this situation inhibits reading achievement, teachers should seek Blue Jay potential in

  9. Using the Blue Gourami in Ethological and Embryological Studies.

    ERIC Educational Resources Information Center

    Thompson, Theresa; Pollak, Edward I.

    1981-01-01

    Lists advantages in the use of the blue gourami in laboratory experiments on reproduction and embryogenesis. Materials and procedures for maintaining and spawning blue gouramis are provided. Also includes details on microscopic examination of developing embryos and histological techniques for microscope slide preparation. (CS)

  10. 75 FR 5485 - Blue Ribbon Commission on America's Nuclear Future

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... HOUSE, WASHINGTON, January 29, 2010 [FR Doc. 2010-2421 Filed 2-2-10; 8:45 am] Billing code 6450-01-P ... Documents#0;#0; ] Memorandum of January 29, 2010 Blue Ribbon Commission on America's Nuclear Future... material. Accordingly, I request that you establish a Blue Ribbon Commission on America's Nuclear...

  11. 3 CFR - Blue Ribbon Commission on America's Nuclear Future

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 3 The President 1 2011-01-01 2011-01-01 false Blue Ribbon Commission on America's Nuclear Future Presidential Documents Other Presidential Documents Memorandum of January 29, 2010 Blue Ribbon Commission on America's Nuclear Future Memorandum for the Secretary of Energy Expanding our Nation's capacity to generate clean nuclear energy is crucial...

  12. Conservation Reasoning Ability and Performance on BSCS Blue Version Examinations

    ERIC Educational Resources Information Center

    Lawson, Anton E.; Nordland, Floyd H.

    1977-01-01

    Twenty-three high school biology students using the Biological Sciences Curriculum Study (BSCS) Blue Textbook were administered a weight conservation and two volume conservation tasks. A majority performed below formal-operational level, indicating that these students would be likely to encounter difficuluty with BSCS Blue Version materials. (MLH)

  13. Blue light effects on rose photosynthesis and photomorphogenesis.

    PubMed

    Abidi, F; Girault, T; Douillet, O; Guillemain, G; Sintes, G; Laffaire, M; Ben Ahmed, H; Smiti, S; Huché-Thélier, L; Leduc, N

    2013-01-01

    Through its impact on photosynthesis and morphogenesis, light is the environmental factor that most affects plant architecture. Using light rather than chemicals to manage plant architecture could reduce the impact on the environment. However, the understanding of how light modulates plant architecture is still poor and further research is needed. To address this question, we examined the development of two rose cultivars, Rosa hybrida'Radrazz' and Rosa chinensis'Old Blush', cultivated under two light qualities. Plants were grown from one-node cuttings for 6 weeks under white or blue light at equal photosynthetic efficiencies. While plant development was totally inhibited in darkness, blue light could sustain full development from bud burst until flowering. Blue light reduced the net CO(2) assimilation rate of fully expanded leaves in both cultivars, despite increasing stomatal conductance and intercellular CO(2) concentrations. In 'Radrazz', the reduction in CO(2) assimilation under blue light was related to a decrease in photosynthetic pigment content, while in both cultivars, the chl a/b ratio increased. Surprisingly, blue light could induce the same organogenetic activity of the shoot apical meristem, growth of the metamers and flower development as white light. The normal development of rose plants under blue light reveals the strong adaptive properties of rose plants to their light environment. It also indicates that photomorphogenetic processes can all be triggered by blue wavelengths and that despite a lower assimilation rate, blue light can provide sufficient energy via photosynthesis to sustain normal growth and development in roses. PMID:22686322

  14. Contemporary Use of Ticagrelor in Interventional Practice (from Blue Cross Blue Shield of Michigan Cardiovascular Consortium).

    PubMed

    Karve, Amrita M; Seth, Milan; Sharma, Manoj; LaLonde, Thomas; Dixon, Simon; Wohns, David; Gurm, Hitinder S

    2015-06-01

    Ticagrelor has greater antiplatelet activity than clopidogrel and is approved for use in patients with acute coronary syndrome (ACS). There are limited data on use of ticagrelor in real-world practice. We assessed ticagrelor use in 64,600 patients who underwent percutaneous coronary intervention from January 2012 to March 2014 at 47 Michigan hospitals in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium. Preprocedural risk of major adverse events was estimated with Blue Cross Blue Shield of Michigan Cardiovascular Consortium risk prediction models. The proportion of patients receiving clopidogrel, prasugrel, and ticagrelor was 72% (n = 46,864), 20% (n = 12,596), and 8% (n = 5,140), respectively, using ticagrelor increasing over time. Ticagrelor was used at 45 hospitals, ranging from 0.5% to 64.9% of discharges. Patients receiving ticagrelor were older (63.6 vs 59.4), more often women (32.9% vs 26.7%), and were more likely to present with ST-segment elevation myocardial infarction (24.4% vs 18.8%), cardiogenic shock within 24 hours (1.3% vs 0.9%), and anginal class IV (47.8% vs 43.0%) (p <0.05). Compared with prasugrel, ticagrelor was prescribed in patients with a higher predicted risk of percutaneous coronary intervention complications: contrast nephropathy (2.5% vs 1.6%), transfusion (2.2% vs 1.4%), and death (1.2% vs 0.7%) (p <0.001); >10% of patients were given prasugrel or ticagrelor for a non-ACS indication. Ticagrelor is prescribed to a higher risk population, and 1 in 10 patients prescribed ticagrelor or prasugrel did not have ACS. PMID:25846767

  15. How does the blue-ringed octopus (Hapalochlaena lunulata) flash its blue rings?

    PubMed

    Mäthger, Lydia M; Bell, George R R; Kuzirian, Alan M; Allen, Justine J; Hanlon, Roger T

    2012-11-01

    The blue-ringed octopus (Hapalochlaena lunulata), one of the world's most venomous animals, has long captivated and endangered a large audience: children playing at the beach, divers turning over rocks, and biologists researching neurotoxins. These small animals spend much of their time in hiding, showing effective camouflage patterns. When disturbed, the octopus will flash around 60 iridescent blue rings and, when strongly harassed, bite and deliver a neurotoxin that can kill a human. Here, we describe the flashing mechanism and optical properties of these rings. The rings contain physiologically inert multilayer reflectors, arranged to reflect blue-green light in a broad viewing direction. Dark pigmented chromatophores are found beneath and around each ring to enhance contrast. No chromatophores are above the ring; this is unusual for cephalopods, which typically use chromatophores to cover or spectrally modify iridescence. The fast flashes are achieved using muscles under direct neural control. The ring is hidden by contraction of muscles above the iridophores; relaxation of these muscles and contraction of muscles outside the ring expose the iridescence. This mechanism of producing iridescent signals has not previously been reported in cephalopods and we suggest that it is an exceptionally effective way to create a fast and conspicuous warning display. PMID:23053367

  16. The invention of blue and purple pigments in ancient times.

    PubMed

    Berke, Heinz

    2007-01-01

    This tutorial review examines manmade blue and purple pigments appearing in antiquity. They were obtained by chemical synthesis from mineral starting materials and refer to chemical compounds: Egyptian Blue (CaCuSi4O10), Han Blue (BaCuSi4O10) and Han Purple (BaCuSi2O6), Maya Blue (x.indigo.(Mg,Al)4Si8(O,OH,H2O)24) and Ultramarine Blue (Na,Ca)8(AlSiO12)(S, SO4,Cl). The Egyptian and Chinese copper-based pigments are assumed to have been developed independently and are presumably an outcome of the historical developments in glazing techniques. A technology transfer from Egypt into China cannot be fully excluded but, based on the facts acquired up to now, looks less probable. PMID:17173142

  17. Ochrovirga pacifica gen. nov., sp. nov., a novel agar-lytic marine bacterium of the family Flavobacteriaceae isolated from a seaweed.

    PubMed

    Kwon, Young-Kyung; Kim, Ji Hyung; Kim, Jennifer Jooyoun; Yang, Sung-Hyun; Ye, Bo-Ram; Heo, Soo-Jin; Hyun, Jung-Ho; Qian, Zhong-Ji; Park, Heung-Sik; Kang, Do-Hyung; Oh, Chulhong

    2014-10-01

    A strain designated as S85(T) was isolated from a seaweed collected from coastal area of Chuuk State in Micronesia. The strain was gram-negative, rod-shaped, and non-motile and formed yellow colonies on the SWY agar (0.2 % yeast extract and 1.5 % agar in seawater) and Marine agar 2216. The strain grew at pH 5-9 (optimum, pH 8), at 15-40 °C (optimum, 25-28 °C), and with 1-9 % (w/v) NaCl (optimum, 3 %). The phylogenetic analysis based on 16S rRNA gene sequence showed that strain S85(T) was related to Lutibacter litoralis CL-TF09(T) and Maritimimonas rapanae A31(T) with 91.4 % and with 90.5 % similarity, respectively. The dominant fatty acids were iso-C15:0, iso-C15:0 3-OH and iso-C17:0 3-OH, C16:0 3-OH and summed feature 3 (C16:1 ω7c and/or iso-C15:0 2-OH). The major isoprenoid quinone was MK-6. The DNA G+C content of the type strain was 34.6 mol %. The major polar lipids were phosphatidylethanolamine, an unknown glycolipid and two unknown polar lipids. Based on this polyphasic taxonomic data, strain S85(T) stands for a novel species of a new genus, and we propose the name Ochrovirga pacifica gen. nov., sp. nov. The type strain of O. pacifica is S85(T) (=KCCM 90106 =JCM 18327(T)). PMID:24842302

  18. Effect of post-treatments and concentration of cotton linter cellulose nanocrystals on the properties of agar-based nanocomposite films.

    PubMed

    Oun, Ahmed A; Rhim, Jong-Whan

    2015-12-10

    Cellulose nanocrystals (CNCs) were prepared by acid hydrolysis of cotton linter pulp fibers and three different purification methods, i.e., without post purification (CNC1), dialyzed against distilled water (CNC2), and neutralized with NaOH (CNC3), and their effect on film properties was evaluated by preparation of agar/CNCs composite films. All the CNCs were rod in shape with diameter of 15-50 nm and length of 210-480 nm. FTIR result indicated that there was no distinctive differences in the chemical structure between CNCs and cotton linter cellulose fiber. No significant relationship was observed between the sulfate content and crystallinity index of CNCs. The CNC3 showed higher thermal stability than the other type of CNCs due to the less adverse effect on the thermal stability of sulfate groups induced by the neutralization with NaOH. The tensile strength (TS) of agar film increased by 15% with incorporation of 5 wt% of CNC3, on the contrary, it decreased by 10% and 15% with incorporation of CNC1 and CNC2, respectively. Other performance properties of agar/CNCs composite films such as optical and water vapor barrier properties showed that the CNC3 was more effective filler than the other CNCs. In the range of concentration of CNC3 tested (1-10 wt%), inclusion of 5 wt% of CNC3 was the maximum concentration for improving or maintaining film properties of the composite films. The neutralization of acid hydrolyzed cellulose using NaOH was simple and convenient for the preparation of CNC and bionanocomposite films. PMID:26428095

  19. Investigation of the effect of power ultrasound on the nucleation of water during freezing of agar gel samples in tubing vials.

    PubMed

    Kiani, Hossein; Sun, Da-Wen; Delgado, Adriana; Zhang, Zhihang

    2012-05-01

    Nucleation, as an important stage of freezing process, can be induced by the irradiation of power ultrasound. In this study, the effect of irradiation temperature (-2 °C, -3 °C, -4 °C and -5 °C), irradiation duration (0s, 1s, 3s, 5s, 10s or 15s) and ultrasound intensity (0.07 W cm(-2), 0.14 W cm(-2), 0.25 W cm(-2), 0.35 W cm(-2) and 0.42 W cm(-2)) on the dynamic nucleation of ice in agar gel samples was studied. The samples were frozen in an ethylene glycol-water mixture (-20 °C) in an ultrasonic bath system after putting them into tubing vials. Results indicated that ultrasound irradiation is able to initiate nucleation at different supercooled temperatures (from -5 °C to -2 °C) in agar gel if optimum intensity and duration of ultrasound were chosen. Evaluation of the effect of 0.25 W cm(-2) ultrasound intensity and different durations of ultrasound application on agar gels showed that 1s was not long enough to induce nucleation, 3s induced the nucleation repeatedly but longer irradiation durations resulted in the generation of heat and therefore nucleation was postponed. Investigation of the effect of ultrasound intensity revealed that higher intensities of ultrasound were effective when a shorter period of irradiation was used, while lower intensities only resulted in nucleation when a longer irradiation time was applied. In addition to this, higher intensities were not effective at longer irradiation times due to the heat generated in the samples by the heating effect of ultrasound. In conclusion, the use of ultrasound as a means to control the crystallization process offers promising application in freezing of solid foods, however, optimum conditions should be selected. PMID:22070859

  20. Light?scattering sensor for real?time identification of Vibrio parahaemolyticus, Vibrio vulnificus and Vibrio cholerae colonies on solid agar plate

    PubMed Central

    Huff, Karleigh; Aroonnual, Amornrat; Littlejohn, Amy E. Fleishman; Rajwa, Bartek; Bae, Euiwon; Banada, Padmapriya P.; Patsekin, Valery; Hirleman, E. Daniel; Robinson, J. Paul; Richards, Gary P.; Bhunia, Arun K.

    2012-01-01

    Summary The three most common pathogenic species of Vibrio, Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus, are of major concerns due to increased incidence of water? and seafood?related outbreaks and illness worldwide. Current methods are lengthy and require biochemical and molecular confirmation. A novel label?free forward light?scattering sensor was developed to detect and identify colonies of these three pathogens in real time in the presence of other vibrios in food or water samples. Vibrio colonies grown on agar plates were illuminated by a 635?nm laser beam and scatter?image signatures were acquired using a CCD (charge?coupled device) camera in an automated BARDOT (BActerial Rapid Detection using Optical light?scattering Technology) system. Although a limited number of Vibrio species was tested, each produced a unique light?scattering signature that is consistent from colony to colony. Subsequently a pattern recognition system analysing the collected light?scatter information provided classification in 1?2?min with an accuracy of 99%. The light?scattering signatures were unaffected by subjecting the bacteria to physiological stressors: osmotic imbalance, acid, heat and recovery from a viable but non?culturable state. Furthermore, employing a standard sample enrichment in alkaline peptone water for 6?h followed by plating on selective thiosulphate citrate bile salts sucrose agar at 30C for ??12?h, the light?scattering sensor successfully detected V.?cholerae, V.?parahaemolyticus and V.?vulnificus present in oyster or water samples in 18?h even in the presence of other vibrios or other bacteria, indicating the suitability of the sensor as a powerful screening tool for pathogens on agar plates. PMID:22613192