Sample records for defined minimal medium

  1. Systematic development and optimization of chemically defined medium supporting high cell density growth of Bacillus coagulans.

    PubMed

    Chen, Yu; Dong, Fengqing; Wang, Yonghong

    2016-09-01

    With determined components and experimental reducibility, the chemically defined medium (CDM) and the minimal chemically defined medium (MCDM) are used in many metabolism and regulation studies. This research aimed to develop the chemically defined medium supporting high cell density growth of Bacillus coagulans, which is a promising producer of lactic acid and other bio-chemicals. In this study, a systematic methodology combining the experimental technique with flux balance analysis (FBA) was proposed to design and simplify a CDM. The single omission technique and single addition technique were employed to determine the essential and stimulatory compounds, before the optimization of their concentrations by the statistical method. In addition, to improve the growth rationally, in silico omission and addition were performed by FBA based on the construction of a medium-size metabolic model of B. coagulans 36D1. Thus, CDMs were developed to obtain considerable biomass production of at least five B. coagulans strains, in which two model strains B. coagulans 36D1 and ATCC 7050 were involved.

  2. A defined, glucose-limited mineral medium for the cultivation of Listeria spp.

    PubMed

    Schneebeli, Rudolf; Egli, Thomas

    2013-04-01

    Members of the genus Listeria are fastidious bacteria with respect to their nutritional requirements, and several minimal media described in the literature fail to support growth of all Listeria spp. Furthermore, strict limitation by a single nutrient, e.g., the carbon source, has not been demonstrated for any of the published minimal media. This is an important prerequisite for defined studies of growth and physiology, including "omics." Based on a theoretical analysis of previously published mineral media for Listeria, an improved, well-balanced growth medium was designed. It supports the growth, not only of all tested Listeria monocytogenes strains, but of all other Listeria species, with the exception of L. ivanovii. The growth performance of L. monocytogenes strain Scott A was tested in the newly designed medium; glucose served as the only carbon and energy source for growth, whereas neither the supplied amino acids nor the buffering and complexing components (MOPS [morpholinepropanesulfonic acid] and EDTA) supported growth. Omission of amino acids, trace elements, or vitamins, alone or in combination, resulted in considerably reduced biomass yields. Furthermore, we monitored the specific growth rates of various Listeria strains cultivated in the designed mineral medium and compared them to growth in complex medium (brain heart infusion broth [BHI]). The novel mineral medium was optimized for the commonly used strain L. monocytogenes Scott A to achieve optimum cell yields and maximum specific growth rates. This mineral medium is the first published synthetic medium for Listeria that has been shown to be strictly carbon (glucose) limited.

  3. A Defined, Glucose-Limited Mineral Medium for the Cultivation of Listeria spp.

    PubMed Central

    Schneebeli, Rudolf

    2013-01-01

    Members of the genus Listeria are fastidious bacteria with respect to their nutritional requirements, and several minimal media described in the literature fail to support growth of all Listeria spp. Furthermore, strict limitation by a single nutrient, e.g., the carbon source, has not been demonstrated for any of the published minimal media. This is an important prerequisite for defined studies of growth and physiology, including “omics.” Based on a theoretical analysis of previously published mineral media for Listeria, an improved, well-balanced growth medium was designed. It supports the growth, not only of all tested Listeria monocytogenes strains, but of all other Listeria species, with the exception of L. ivanovii. The growth performance of L. monocytogenes strain Scott A was tested in the newly designed medium; glucose served as the only carbon and energy source for growth, whereas neither the supplied amino acids nor the buffering and complexing components (MOPS [morpholinepropanesulfonic acid] and EDTA) supported growth. Omission of amino acids, trace elements, or vitamins, alone or in combination, resulted in considerably reduced biomass yields. Furthermore, we monitored the specific growth rates of various Listeria strains cultivated in the designed mineral medium and compared them to growth in complex medium (brain heart infusion broth [BHI]). The novel mineral medium was optimized for the commonly used strain L. monocytogenes Scott A to achieve optimum cell yields and maximum specific growth rates. This mineral medium is the first published synthetic medium for Listeria that has been shown to be strictly carbon (glucose) limited. PMID:23377938

  4. Improvement in ethanol productivity of engineered E. coli strain SSY13 in defined medium via adaptive evolution.

    PubMed

    Jilani, Syed Bilal; Venigalla, Siva Sai Krishna; Mattam, Anu Jose; Dev, Chandra; Yazdani, Syed Shams

    2017-09-01

    E. coli has the ability to ferment both C5 and C6 sugars and produce mixture of acids along with small amount of ethanol. In our previous study, we reported the construction of an ethanologenic E. coli strain by modulating flux through the endogenous pathways. In the current study, we made further changes in the strain to make the overall process industry friendly; the changes being (1) removal of plasmid, (2) use of low-cost defined medium, and (3) improvement in consumption rate of both C5 and C6 sugars. We first constructed a plasmid-free strain SSY13 and passaged it on AM1-xylose minimal medium plate for 150 days. Further passaging was done for 56 days in liquid AM1 medium containing either glucose or xylose on alternate days. We observed an increase in specific growth rate and carbon utilization rate with increase in passage numbers until 42 days for both glucose and xylose. The 42nd day passaged strain SSK42 fermented 113 g/L xylose in AM1 minimal medium and produced 51.1 g/L ethanol in 72 h at 89% of maximum theoretical yield with ethanol productivity of 1.4 g/L/h during 24-48 h of fermentation. The ethanol titer, yield and productivity were 49, 40 and 36% higher, respectively, for SSK42 as compared to unevolved SSY13 strain.

  5. Schlieren System and method for moving objects

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor)

    1995-01-01

    A system and method are provided for recording density changes in a flow field surrounding a moving object. A mask having an aperture for regulating the passage of images is placed in front of an image recording medium. An optical system is placed in front of the mask. A transition having a light field-of-view and a dark field-of-view is located beyond the test object. The optical system focuses an image of the transition at the mask such that the aperture causes a band of light to be defined on the image recording medium. The optical system further focuses an image of the object through the aperture of the mask so that the image of the object appears on the image recording medium. Relative motion is minimized between the mask and the transition. Relative motion is also minimized between the image recording medium and the image of the object. In this way, the image of the object and density changes in a flow field surrounding the object are recorded on the image recording medium when the object crosses the transition in front of the optical system.

  6. Nitrogen and Sulfur Requirements for Clostridium thermocellum and Caldicellulosiruptor bescii on Cellulosic Substrates in Minimal Nutrient Media

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kridelbaugh, Donna M; Nelson, Josh C; Engle, Nancy L

    2013-01-01

    Growth media for cellulolytic Clostridium thermocellum and Caldicellulosiruptor bescii bacteria usually contain excess nutrients that would increase costs for consolidated bioprocessing for biofuel production and create a waste stream with nitrogen, sulfur and phosphate. C. thermocellum was grown on crystalline cellulose with varying concentrations of nitrogen and sulfur compounds, and growth rate and alcohol production response curves were determined. Both bacteria assimilated sulfate in the presence of ascorbate reductant, increasing the ratio of oxidized to reduced fermentation products. From these results, a low ionic strength, defined minimal nutrient medium with decreased nitrogen, sulfur, phosphate and vitamin supplements was developed formore » the fermentation of cellobiose, cellulose and acid-pretreated Populus. Carbon and electron balance calculations indicate the unidentified residual fermentation products must include highly reduced molecules. Both bacterial populations were maintained in co-cultures with substrates containing xylan or hemicellulose in defined medium with sulfate and basal vitamin supplements.« less

  7. Design of an efficient medium for heterologous protein production in Yarrowia lipolytica: case of human interferon alpha 2b.

    PubMed

    Gasmi, Najla; Ayed, Atef; Nicaud, Jean-Marc; Kallel, Héla

    2011-05-20

    The non conventional yeast Yarrowia lipolytica has aroused a strong industrial interest for heterologous protein production. However most of the studies describing recombinant protein production by this yeast rely on the use of complex media, such media are not convenient for large scale production particularly for products intended for pharmaceutical applications. In addition medium composition can also affect the production yield. Hence it is necessary to design an efficient medium for therapeutic protein expression by this host. Five different media, including four minimal media and a complex medium, were assessed in shake flasks for the production of human interferon alpha 2b (hIFN α2b) by Y. lipolytica under the control of POX2 promoter inducible with oleic acid. The chemically defined medium SM4 formulated by Invitrogen for Pichia pastoris growth was the most suitable. Using statistical experimental design this medium was further optimized. The selected minimal medium consisting in SM4 supplemented with 10 mg/l FeCl₃, 1 g/l glutamate, 5 ml/l PTM1 (Pichia Trace Metals) solution and a vitamin solution composed of myo-inositol, thiamin and biotin was called GNY medium. Compared to shake flask, bioreactor culture in GNY medium resulted in 416-fold increase of hIFN α2b production and 2-fold increase of the biological activity. Furthermore, SM4 enrichment with 5 ml/l PTM1 solution contributed to protect hIFN α2b against the degradation by the 28 kDa protease identified by zymography gel in culture supernatant. The screening of the inhibitory effect of the trace elements present in PTM1 solution on the activity of this protease was achieved using a Box-Behnken design. Statistical data analysis showed that FeCl₃ and MnSO₄ had the most inhibitory effect. We have designed an efficient medium for large scale production of heterologous proteins by Y. lipolytica. The optimized medium GNY is suitable for the production of hIFN α2b with the advantage that no complex nitrogen sources with non-defined composition were required.

  8. Development of low cost medium for ethanol production from syngas by Clostridium ragsdalei.

    PubMed

    Gao, Jie; Atiyeh, Hasan K; Phillips, John R; Wilkins, Mark R; Huhnke, Raymond L

    2013-11-01

    The development of a low cost medium for ethanol production is critical for process feasibility. Ten media were formulated for Clostridium ragsdalei by reduction, elimination and replacement of expensive nutrients. Cost analysis and effects of medium components on growth and product formation were investigated. Fermentations were performed in 250 mL bottles using syngas (20% CO, 15% CO2, 5% H2 and 60% N2). The standard medium M1 cost is $9.83/L, of which 93% is attributed to morpholinoethane sulfonic acid (MES) buffer. Statistical analysis of the results showed that MES removal did not affect cell growth and ethanol production (P>0.05). Based on cells' elemental composition, a minimal mineral concentration medium M7 was formulated, which provided 29% higher ethanol yield from CO at 3% of the cost compared to medium M1. Ethanol yield from CO in the completely defined medium M9 was 36% higher than while at 5% the cost of medium M1. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Assessing the impact of minimizing arginine conversion in fully defined SILAC culture medium in human embryonic stem cells.

    PubMed

    Scheerlinck, Ellen; Van Steendam, Katleen; Daled, Simon; Govaert, Elisabeth; Vossaert, Liesbeth; Meert, Paulien; Van Nieuwerburgh, Filip; Van Soom, Ann; Peelman, Luc; De Sutter, Petra; Heindryckx, Björn; Dhaenens, Maarten; Deforce, Dieter

    2016-10-01

    We present a fully defined culture system (adapted Essential8 TM [E8 TM ] medium in combination with vitronectin) for human embryonic stem cells that can be used for SILAC purposes. Although a complete incorporation of the labels was observed after 4 days in culture, over 90% of precursors showed at least 10% conversion. To reduce this arginine conversion, E8 TM medium was modified by adding (1) l-proline, (2) l-ornithine, (3) N ω -hydroxy-nor-l-arginine acetate, or by (4) lowering the arginine concentration. Reduction of arginine conversion was best obtained by adding 5 mM l-ornithine, followed by 3.5 mM l-proline and by lowering the arginine concentration in the medium to 99.5 μM. No major changes in pluripotency and cell amount could be observed for the adapted E8 TM media with ornithine and proline. However, our subsequent ion mobility assisted data-independent acquisition (high-definition MS) proteome analysis cautions for ongoing changes in the proteome when aiming at longer term suppression of arginine conversion. © 2016 The Authors. Proteomics Published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Development of Competence of Haemophilus influenzae

    PubMed Central

    Spencer, Hugh T.; Herriott, Roger M.

    1965-01-01

    Spencer, Hugh T. (The Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md.), and Roger M. Herriott. Development of competence of Haemophilus influenzae. J. Bacteriol. 90:911–920. 1965.—A chemically defined nongrowth medium was developed for the induction of competence of Haemophilus influenzae by a stepdown procedure. Cells grown logarithmically in Heart Infusion Broth became competent after being transferred to a medium which consisted of amino acids, sodium fumarate, and inorganic salts. Chloramphenicol (2 μg/ml) or l-valine (1 μg/ml) in the nongrowth medium inhibited development of competence. The inhibitory action of l-valine was reversed by comparable concentrations of l-isoleucine. Kinetic studies of the development of competence showed a variable capacity of competent cells to take up deoxyribonucleic acid and reaffirmed earlier findings that competence was not transmissible in H. influenzae. Addition of nicotinamide adenine dinucleotide, thiamine, calcium pantothenate, uracil, and hypoxanthine to the medium for competence resulted in a minimal growth medium in which reduced levels of competence were developed. PMID:5294817

  11. Cultivation of a native alga for biomass and biofuel accumulation in coal bed methane production water

    USGS Publications Warehouse

    Hodgskiss, Logan H.; Nagy, Justin; Barnhart, Elliott P.; Cunningham, Alfred B.; Fields, Matthew W.

    2016-01-01

    Coal bed methane (CBM) production has resulted in thousands of ponds in the Powder River Basin of low-quality water in a water-challenged region. A green alga isolate, PW95, was isolated from a CBM production pond, and analysis of a partial ribosomal gene sequence indicated the isolate belongs to the Chlorococcaceae family. Different combinations of macro- and micronutrients were evaluated for PW95 growth in CBM water compared to a defined medium. A small level of growth was observed in unamended CBM water (0.15 g/l), and biomass increased (2-fold) in amended CBM water or defined growth medium. The highest growth rate was observed in CBM water amended with both N and P, and the unamended CBM water displayed the lowest growth rate. The highest lipid content (27%) was observed in CBM water with nitrate, and a significant level of lipid accumulation was not observed in the defined growth medium. Growth analysis indicated that nitrate deprivation coincided with lipid accumulation in CBM production water, and lipid accumulation did not increase with additional phosphorus limitation. The presented results show that CBM production wastewater can be minimally amended and used for the cultivation of a native, lipid-accumulating alga.

  12. Defining the minimal detectable change in scores on the eight-item Morisky Medication Adherence Scale.

    PubMed

    Muntner, Paul; Joyce, Cara; Holt, Elizabeth; He, Jiang; Morisky, Donald; Webber, Larry S; Krousel-Wood, Marie

    2011-05-01

    Self-report scales are used to assess medication adherence. Data on how to discriminate change in self-reported adherence over time from random variability are limited. To determine the minimal detectable change for scores on the 8-item Morisky Medication Adherence Scale (MMAS-8). The MMAS-8 was administered twice, using a standard telephone script, with administration separated by 14-22 days, to 210 participants taking antihypertensive medication in the CoSMO (Cohort Study of Medication Adherence among Older Adults). MMAS-8 scores were calculated and participants were grouped into previously defined categories (<6, 6 to <8, and 8 for low, medium, and high adherence). The mean (SD) age of participants was 78.1 (5.8) years, 43.8% were black, and 68.1% were women. Overall, 8.1% (17/210), 16.2% (34/210), and 51.0% (107/210) of participants had low, medium, and high MMAS-8 scores, respectively, at both survey administrations (overall agreement 75.2%; 158/210). The weighted κ statistic was 0.63 (95% CI 0.53 to 0.72). The intraclass correlation coefficient was 0.78. The within-person standard error of the mean for change in MMAS-8 scores was 0.81, which equated to a minimal detectable change of 1.98 points. Only 4.3% (9/210) of the participants had a change in MMAS-8 of 2 or more points between survey administrations. Within-person changes in MMAS-8 scores of 2 or more points over time may represent a real change in antihypertensive medication adherence.

  13. Regulation of Fumonisin B1 Biosynthesis and Conidiation in Fusarium verticillioides by a Cyclin-Like (C-Type) Gene, FCC1†

    PubMed Central

    Shim, Won-Bo; Woloshuk, Charles P.

    2001-01-01

    Fumonisins are a group of mycotoxins produced in corn kernels by the plant-pathogenic fungus Fusarium verticillioides. A mutant of the fungus, FT536, carrying a disrupted gene named FCC1 (for Fusarium cyclin C1) resulting in altered fumonisin B1 biosynthesis was generated. FCC1 contains an open reading frame of 1,018 bp, with one intron, and encodes a putative 319-amino-acid polypeptide. This protein is similar to UME3 (also called SRB11 or SSN8), a cyclin C of Saccharomyces cerevisiae, and contains three conserved motifs: a cyclin box, a PEST-rich region, and a destruction box. Also similar to the case for C-type cyclins, FCC1 was constitutively expressed during growth. When strain FT536 was grown on corn kernels or on defined minimal medium at pH 6, conidiation was reduced and FUM5, the polyketide synthase gene involved in fumonisin B1 biosynthesis, was not expressed. However, when the mutant was grown on a defined minimal medium at pH 3, conidiation was restored, and the blocks in expression of FUM5 and fumonisin B1 production were suppressed. Our data suggest that FCC1 plays an important role in signal transduction regulating secondary metabolism (fumonisin biosynthesis) and fungal development (conidiation) in F. verticillioides. PMID:11282612

  14. Characterization of the extremely arsenic-resistant Brevibacterium linens strain AE038-8 isolated from contaminated groundwater in Tucuman, Argentina

    DOE PAGES

    Maizel, Daniela; Blum, Jodi Switzer; Ferrero, Marcela A.; ...

    2015-12-10

    Brevibacterium linens AE038-8, isolated from As-contaminated groundwater in Tucumán (Argentina), is highly resistant to arsenic oxyanions, being able to tolerate up to 1 M As(V) and 75 mM As(III) in a complex medium. Strain AE038-8 was also able to reduce As(V) to As(III) when grown in complex medium but paradoxically it could not do this in a defined minimal medium with sodium acetate and ammonium sulfate as carbon and nitrogen sources, respectively. No oxidation of As(III) to As(V) was observed under any conditions. Here, three copies of the ars operon comprising arsenic resistance genes were found on B. linens AE038-8more » genome. In addition to the well known arsC, ACR3 and arsR, two copies of the arsO gene of unknown function were detected.« less

  15. Characterization of the extremely arsenic-resistant Brevibacterium linens strain AE038-8 isolated from contaminated groundwater in Tucuman, Argentina

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maizel, Daniela; Blum, Jodi Switzer; Ferrero, Marcela A.

    Brevibacterium linens AE038-8, isolated from As-contaminated groundwater in Tucumán (Argentina), is highly resistant to arsenic oxyanions, being able to tolerate up to 1 M As(V) and 75 mM As(III) in a complex medium. Strain AE038-8 was also able to reduce As(V) to As(III) when grown in complex medium but paradoxically it could not do this in a defined minimal medium with sodium acetate and ammonium sulfate as carbon and nitrogen sources, respectively. No oxidation of As(III) to As(V) was observed under any conditions. Here, three copies of the ars operon comprising arsenic resistance genes were found on B. linens AE038-8more » genome. In addition to the well known arsC, ACR3 and arsR, two copies of the arsO gene of unknown function were detected.« less

  16. Chemically defined medium and Caenorhabditis elegans

    NASA Technical Reports Server (NTRS)

    Szewczyk, Nathaniel J.; Kozak, Elena; Conley, Catharine A.

    2003-01-01

    BACKGROUND: C. elegans has been established as a powerful genetic system. Use of a chemically defined medium (C. elegans Maintenance Medium (CeMM)) now allows standardization and systematic manipulation of the nutrients that animals receive. Liquid cultivation allows automated culturing and experimentation and should be of use in large-scale growth and screening of animals. RESULTS: We find that CeMM is versatile and culturing is simple. CeMM can be used in a solid or liquid state, it can be stored unused for at least a year, unattended actively growing cultures may be maintained longer than with standard techniques, and standard C. elegans protocols work well with animals grown in defined medium. We also find that there are caveats to using defined medium. Animals in defined medium grow more slowly than on standard medium, appear to display adaptation to the defined medium, and display altered growth rates as they change the composition of the defined medium. CONCLUSIONS: As was suggested with the introduction of C. elegans as a potential genetic system, use of defined medium with C. elegans should prove a powerful tool.

  17. Contribution of volatiles to the antifungal effect of Lactobacillus paracasei in defined medium and yogurt.

    PubMed

    Aunsbjerg, S D; Honoré, A H; Marcussen, J; Ebrahimi, P; Vogensen, F K; Benfeldt, C; Skov, T; Knøchel, S

    2015-02-02

    Lactic acid bacteria with antifungal properties can be used to control spoilage of food and feed. Previously, most of the identified metabolites have been isolated from cell-free fermentate of lactic acid bacteria with methods suboptimal for detecting possible contribution from volatiles to the antifungal activity. The role of volatile compounds in the antifungal activity of Lactobacillus paracasei DGCC 2132 in a chemically defined interaction medium (CDIM) and yogurt was therefore investigated with a sampling technique minimizing volatile loss. Diacetyl was identified as the major volatile produced by L. paracasei DGCC 2132 in CDIM. When the strain was added to a yogurt medium diacetyl as well as other volatiles also increased but the metabolome was more complex. Removal of L. paracasei DGCC 2132 cells from CDIM fermentate resulted in loss of both volatiles, including diacetyl, and the antifungal activity towards two strains of Penicillium spp. When adding diacetyl to CDIM or yogurt without L. paracasei DGCC 2132, marked inhibition was observed. Besides diacetyl, the antifungal properties of acetoin were examined, but no antifungal activity was observed. Overall, the results demonstrate the contribution of diacetyl in the antifungal effect of L. paracasei DGCC 2132 and indicate that the importance of volatiles may have been previously underestimated. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Nutrient Composition Promotes Switching between Pellicle and Bottom Biofilm in Salmonella

    PubMed Central

    Paytubi, Sonia; Cansado, Cintia; Madrid, Cristina; Balsalobre, Carlos

    2017-01-01

    Salmonella is one of the most frequently reported causes of foodborne illness worldwide. Non-typhoidal serovars cause gastroenteritis in humans. Salmonella can grow on surfaces forming biofilms, contributing to its persistence since biofilms are difficult to eradicate due to the high resistance to antimicrobials and disinfectants. It has been described that there are two crucial biofilm promoting factors in Salmonella: curli and cellulose. The expression of both factors is coordinately regulated by the transcriptional regulator CsgD. Most biofilm studies of Salmonella have been performed by growing bacteria in low osmolarity rich medium and low temperature (25°C). In such conditions, the biofilm is formed at the air–liquid interface (pellicle biofilm). Remarkably, when Salmonella grow in minimal medium, biofilm formation switches from the air–liquid interface to the solid–liquid interface (bottom biofilm). In this report, the switching between pellicle and bottom biofilm has been characterized. Our data indicate that curli, but not cellulose, is crucial for the formation of both kinds of biofilms. In minimal medium, conditions promoting formation of bottom biofilm, a high transcriptional expression of csgD and consequently of the genes involved in the synthesis of curli and cellulose was detected. The nutritional status of the cells seems to be pivotal for the spatial distribution of the biofilms formed. When bacteria is growing in minimal medium the addition of amino acids downregulates the expression of csgB and causes the switch between bottom and pellicle biofilm. The crosstalk between general metabolism and biofilm formation is also highlighted by the fact that the metabolic sensor cAMP modulates the type of biofilm generated by Salmonella. Moreover, cAMP regulates transcriptional expression of csgD and stimulates pellicle biofilm formation, suggesting that the physiological conditions define the type of biofilm formed by Salmonella. The consequences of the switching between pellicle and bottom biofilm during either infection or survival in natural environments remain undercover. PMID:29163440

  19. Nutrient Composition Promotes Switching between Pellicle and Bottom Biofilm in Salmonella.

    PubMed

    Paytubi, Sonia; Cansado, Cintia; Madrid, Cristina; Balsalobre, Carlos

    2017-01-01

    Salmonella is one of the most frequently reported causes of foodborne illness worldwide. Non-typhoidal serovars cause gastroenteritis in humans. Salmonella can grow on surfaces forming biofilms, contributing to its persistence since biofilms are difficult to eradicate due to the high resistance to antimicrobials and disinfectants. It has been described that there are two crucial biofilm promoting factors in Salmonella : curli and cellulose. The expression of both factors is coordinately regulated by the transcriptional regulator CsgD. Most biofilm studies of Salmonella have been performed by growing bacteria in low osmolarity rich medium and low temperature (25°C). In such conditions, the biofilm is formed at the air-liquid interface (pellicle biofilm). Remarkably, when Salmonella grow in minimal medium, biofilm formation switches from the air-liquid interface to the solid-liquid interface (bottom biofilm). In this report, the switching between pellicle and bottom biofilm has been characterized. Our data indicate that curli, but not cellulose, is crucial for the formation of both kinds of biofilms. In minimal medium, conditions promoting formation of bottom biofilm, a high transcriptional expression of csgD and consequently of the genes involved in the synthesis of curli and cellulose was detected. The nutritional status of the cells seems to be pivotal for the spatial distribution of the biofilms formed. When bacteria is growing in minimal medium the addition of amino acids downregulates the expression of csgB and causes the switch between bottom and pellicle biofilm. The crosstalk between general metabolism and biofilm formation is also highlighted by the fact that the metabolic sensor cAMP modulates the type of biofilm generated by Salmonella . Moreover, cAMP regulates transcriptional expression of csgD and stimulates pellicle biofilm formation, suggesting that the physiological conditions define the type of biofilm formed by Salmonella . The consequences of the switching between pellicle and bottom biofilm during either infection or survival in natural environments remain undercover.

  20. Chemically Defined Medium and Caenorhabditis elegans: A Powerful Approach

    NASA Technical Reports Server (NTRS)

    Szewczyk, N. J.; Kozak, E.; Conley, C. A.

    2003-01-01

    C. elegans has been established as a powerful genetic system. Growth in a chemically defined medium (C. elegans Maintenance Medium (CeMM)) now allows standardization and systematic manipulation of the nutrients that animals receive. Liquid cultivation allows automated culturing and experimentation and should be of me in large-scale growth and screening of animals. Here we present our initial results from developing culture systems with CeMM. We find that CeMM is versatile and culturing is simple. CeMM can be used in a solid or liquid state, it can be stored unused for at least a year, unattended actively growing cultures may be maintained longer than with standard techniques, and standard C. elegans protocols work well with animals grown in defined medium. We also find that there are caveats of using defined medium. Animals in defined medium grow more slowly than on standard medium, appear to display adaptation to the defined medium, and display altered growth rates as they change defined medium composition. As was suggested with the introduction of C. elegans as a potential genetic system, use of defined medium with C. elegans should prove a powerful tool.

  1. Optimization of Pre-transplantation Conditions to Enhance the Efficacy of Mesenchymal Stem Cells

    PubMed Central

    Haque, Nazmul; Kasim, Noor Hayaty Abu; Rahman, Mohammad Tariqur

    2015-01-01

    Mesenchymal stem cells (MSCs) are considered a potential tool for cell based regenerative therapy due to their immunomodulatory property, differentiation potentials, trophic activity as well as large donor pool. Poor engraftment and short term survival of transplanted MSCs are recognized as major limitations which were linked to early cellular ageing, loss of chemokine markers during ex vivo expansion, and hyper-immunogenicity to xeno-contaminated MSCs. These problems can be minimized by ex vivo expansion of MSCs in hypoxic culture condition using well defined or xeno-free media i.e., media supplemented with growth factors, human serum or platelet lysate. In addition to ex vivo expansion in hypoxic culture condition using well defined media, this review article describes the potentials of transient adaptation of expanded MSCs in autologous serum supplemented medium prior to transplantation for long term regenerative benefits. Such transient adaptation in autologous serum supplemented medium may help to increase chemokine receptor expression and tissue specific differentiation of ex vivo expanded MSCs, thus would provide long term regenerative benefits. PMID:25678851

  2. Characterization of the extremely arsenic-resistant Brevibacterium linens strain AE038-8 isolated from contaminated groundwater in Tucumán, Argentina

    USGS Publications Warehouse

    Maizel, Daniela; Blum, Jodi S.; Ferrero, Marcela A.; Utturkar, Sagar M.; Brown, Steven D.; Rosen, Barry P.; Oremland, Ronald S.

    2015-01-01

    Brevibacterium linens AE038-8, isolated from As-contaminated groundwater in Tucumán (Argentina), is highly resistant to arsenic oxyanions, being able to tolerate up to 1 M As(V) and 75 mM As(III) in a complex medium. Strain AE038-8 was also able to reduce As(V) to As(III) when grown in complex medium but paradoxically it could not do this in a defined minimal medium with sodium acetate and ammonium sulfate as carbon and nitrogen sources, respectively. No oxidation of As(III) to As(V) was observed under any conditions. Three copies of the ars operon comprising arsenic resistance genes were found on B. linens AE038-8 genome. In addition to the well known arsC, ACR3 andarsR, two copies of the arsO gene of unknown function were detected.

  3. Growth of Bacillus methanolicus in seawater-based media.

    PubMed

    Komives, Claire F; Cheung, Louis Yip-Yan; Pluschkell, Stefanie B; Flickinger, Michael C

    2005-02-01

    Bacillus methanolicus has been proposed as a biocatalyst for the low cost production of commodity chemicals. The organism can use methanol as sole carbon and energy source, and it grows aerobically at elevated temperatures. Methanol can be made available from off-shore conversion of natural gas to methanol, through gas-to-liquid technology. Growth of the organism in seawater-based medium would further reduce the costs of chemical production performed near an off-shore natural gas source. The growth of strain PB1 (ATCC 51375) in shake flask experiments with trypticase soy broth medium showed minimal salt-inhibition at the concentration of NaCl in seawater. The ability of B. methanolicus PB1 to grow in Pacific Ocean water using methanol as a carbon and energy source was also tested. Following a simple adaptation procedure, PB1 was able to grow on methanol in semi-defined medium with 100% seawater with good growth yields and similar growth rates compared with those achieved on media prepared in deionized water.

  4. Comparative RNA-sequencing of the acarbose producer Actinoplanes sp. SE50/110 cultivated in different growth media.

    PubMed

    Schwientek, Patrick; Wendler, Sergej; Neshat, Armin; Eirich, Christina; Rückert, Christian; Klein, Andreas; Wehmeier, Udo F; Kalinowski, Jörn; Stoye, Jens; Pühler, Alfred

    2013-08-20

    Actinoplanes sp. SE50/110 is known as the producer of the alpha-glucosidase inhibitor acarbose, a potent drug in the treatment of type-2 diabetes mellitus. We conducted the first whole transcriptome analysis of Actinoplanes sp. SE50/110, using RNA-sequencing technology for comparative gene expression studies between cells grown in maltose minimal medium, maltose minimal medium with trace elements, and glucose complex medium. We first studied the behavior of Actinoplanes sp. SE50/110 cultivations in these three media and found that the different media had significant impact on growth rate and in particular on acarbose production. It was demonstrated that Actinoplanes sp. SE50/110 grew well in all three media, but acarbose biosynthesis was only observed in cultures grown in maltose minimal medium with and without trace elements. When comparing the expression profiles between the maltose minimal media with and without trace elements, only few significantly differentially expressed genes were found, which mainly code for uptake systems of metal ions provided in the trace element solution. In contrast, the comparison of expression profiles from maltose minimal medium and glucose complex medium revealed a large number of differentially expressed genes, of which the most conspicuous genes account for iron storage and uptake. Furthermore, the acarbose gene cluster was found to be highly expressed in maltose-containing media and almost silent in the glucose-containing medium. In addition, a putative antibiotic biosynthesis gene cluster was found to be similarly expressed as the acarbose cluster. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Characterization of Escherichia coli d-Cycloserine Transport and Resistant Mutants

    PubMed Central

    Baisa, Gary; Stabo, Nicholas J.

    2013-01-01

    d-Cycloserine (DCS) is a broad-spectrum antibiotic that inhibits d-alanine ligase and alanine racemase activity. When Escherichia coli K-12 or CFT073 is grown in minimal glucose or glycerol medium, CycA transports DCS into the cell. E. coli K-12 cycA and CFT073 cycA mutant strains display increased DCS resistance when grown in minimal medium. However, the cycA mutants exhibit no change in DCS sensitivity compared to their parental strains when grown in LB (CFT073 and K-12) or human urine (CFT073 only). These data suggest that cycA does not participate in DCS sensitivity when strains are grown in a non-minimal medium. The small RNA GvcB acts as a negative regulator of E. coli K-12 cycA expression when grown in LB. Three E. coli K-12 gcvB mutant strains failed to demonstrate a change in DCS sensitivity when grown in LB. This further suggests a limited role for cycA in DCS sensitivity. To aid in the identification of E. coli genes involved in DCS sensitivity when grown on complex media, the Keio K-12 mutant collection was screened for DCS-resistant strains. dadA, pnp, ubiE, ubiF, ubiG, ubiH, and ubiX mutant strains showed elevated DCS resistance. The phenotypes associated with these mutants were used to further define three previously characterized E. coli DCS-resistant strains (χ316, χ444, and χ453) isolated by Curtiss and colleagues (R. Curtiss, III, L. J. Charamella, C. M. Berg, and P. E. Harris, J. Bacteriol. 90:1238–1250, 1965). A dadA mutation was identified in both χ444 and χ453. In addition, results are presented that indicate for the first time that DCS can antagonize d-amino acid dehydrogenase (DadA) activity. PMID:23316042

  6. Induction of L-phenylalanine ammonia-lyase during utilization of phenylalanine as a carbon or nitrogen source in Rhodotorula glutinis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marusich, W.C.; Jensen, R.A.; Zamir, L.O.

    Rhodotorula glutinis is a convenient source of L-phenylalanine ammonia-lyase, an enzyme that is useful as a biochemical reagent in the assay of L-phenylalanine. There have been previous descriptions of induced lyase production in complex medium where induction occurs late in exponential growth, suggesting a role in secondary metabolism such as is the case in higher plants. A higher specific activity of L-phenylalanine ammonia-lyase (sixfold higher than in complex medium) can be obtained during midexponential growth in a defined medium containing L-phenylalanine as the sole source of carbon. L-phenylalanine will also induce lyase synthesis during exponential growth in minimal medium inmore » which L-phenylalanine is the sole source of nitrogen. The appearance of lyase in complex medium supplemented with L-phenylalanine is probably triggered fortuitously by exhaustion late in growth of a prime source of nitrogen. In this study, R. glutinis appeared to express a single lyase enzyme, regardless of whether induction was nitrogen signaled or carbon signaled. Thin-layer chromatographic analysis of ether extracts prepared fom cultures induced with doubly labeled (U-/sup 14/C; ring-4-/sup 3/H) L-phenylalanine provided evidence of a catabolic sequence containing cinnamic acid, benzoic acid, and 4-hydroxybenzoic acid as degradative intermediates. 3,4-Dihydroxybenzoic acid was not identified as a catabolic intermediate.« less

  7. Production of xanthan gum from a chemically defined medium introduction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weisrock, W.P.; Klein, H.S.

    1983-02-22

    Heteropolysaccharides produced by the action of Xanthomonas bacteria on carbohydrate media have a potential application as film forming agents, as thickeners in oil field drilling fluids and fracturing liquids and as emulsifying, stabilizing, and sizing agents. Heteropolysaccharides, particularly, xanthan gum, have a significant potential as mobility control agents in micellar polymer flooding. Xanthan gum has excellent viscosifying properties at low concentration, is resistant to shear degradation and exhibits only minimal losses in viscosity as a function of temperature, pH, and ionic strength. For these reasons, xanthan gum is an attractive alternative to synthetic polyacrylamides for enhanced oil recovery operations. 15more » claims.« less

  8. A radiative transfer model for remote sensing of laser induced fluorescence of phytoplankton in non-homogeneous turbid water

    NASA Technical Reports Server (NTRS)

    Venable, D. D.

    1980-01-01

    A radiative transfer computer model was developed to characterize the total flux of chlorophyll a fluoresced or backscattered photons when laser radiation is incident on turbid water that contains a non-homogeneous suspension of inorganic sediments and phytoplankton. The radiative transfer model is based on the Monte Carlo technique and assumes that: (1) the aquatic medium can be represented by a stratified concentration profile; and (2) that appropriate optical parameters can be defined for each layer. The model was designed to minimize the required computer resources and run time. Results are presented for an anacystis marinus culture.

  9. Patient, surgeon, and hospital disparities associated with benign hysterectomy approach and perioperative complications.

    PubMed

    Mehta, Ambar; Xu, Tim; Hutfless, Susan; Makary, Martin A; Sinno, Abdulrahman K; Tanner, Edward J; Stone, Rebecca L; Wang, Karen; Fader, Amanda N

    2017-05-01

    Hysterectomy is among the most common major surgical procedures performed in women. Approximately 450,000 hysterectomy procedures are performed each year in the United States for benign indications. However, little is known regarding contemporary US hysterectomy trends for women with benign disease with respect to operative technique and perioperative complications, and the association between these 2 factors with patient, surgeon, and hospital characteristics. We sought to describe contemporary hysterectomy trends and explore associations between patient, surgeon, and hospital characteristics with surgical approach and perioperative complications. Hysterectomies performed for benign indications by general gynecologists from July 2012 through September 2014 were analyzed in the all-payer Maryland Health Services Cost Review Commission database. We excluded hysterectomies performed by gynecologic oncologists, reproductive endocrinologists, and female pelvic medicine and reconstructive surgeons. We included both open hysterectomies and those performed by minimally invasive surgery, which included vaginal hysterectomies. Perioperative complications were defined using the Agency for Healthcare Research and Quality patient safety indicators. Surgeon hysterectomy volume during the 2-year study period was analyzed (0-5 cases annually = very low, 6-10 = low, 11-20 = medium, and ≥21 = high). We utilized logistic regression and negative binomial regression to identify patient, surgeon, and hospital characteristics associated with minimally invasive surgery utilization and perioperative complications, respectively. A total of 5660 hospitalizations were identified during the study period. Most patients (61.5%) had an open hysterectomy; 38.5% underwent a minimally invasive surgery procedure (25.1% robotic, 46.6% laparoscopic, 28.3% vaginal). Most surgeons (68.2%) were very low- or low-volume surgeons. Factors associated with a lower likelihood of undergoing minimally invasive surgery included older patient age (reference 45-64 years; 20-44 years: adjusted odds ratio, 1.16; 95% confidence interval, 1.05-1.28), black race (reference white; adjusted odds ratio, 0.70; 95% confidence interval, 0.63-0.78), Hispanic ethnicity (adjusted odds ratio, 0.62; 95% confidence interval, 0.48-0.80), smaller hospital (reference large; small: adjusted odds ratio, 0.26; 95% confidence interval, 0.15-0.45; medium: adjusted odds ratio, 0.87; 95% confidence interval, 0.79-0.96), medium hospital hysterectomy volume (reference ≥200 hysterectomies; 100-200: adjusted odds ratio, 0.78; 95% confidence interval, 0.71-0.87), and medium vs high surgeon volume (reference high; medium: adjusted odds ratio, 0.87; 95% confidence interval, 0.78-0.97). Complications occurred in 25.8% of open and 8.2% of minimally invasive hysterectomies (P < .0001). Minimally invasive hysterectomy (adjusted odds ratio, 0.22; 95% confidence interval, 0.17-0.27) and large hysterectomy volume hospitals (reference ≥200 hysterectomies; 1-100: adjusted odds ratio, 2.26; 95% confidence interval, 1.60-3.20; 101-200: adjusted odds ratio, 1.63; 95% confidence interval, 1.23-2.16) were associated with fewer complications, while patient payer, including Medicare (reference private; adjusted odds ratio, 1.86; 95% confidence interval, 1.33-2.61), Medicaid (adjusted odds ratio, 1.63; 95% confidence interval, 1.30-2.04), and self-pay status (adjusted odds ratio, 2.41; 95% confidence interval, 1.40-4.12), and very-low and low surgeon hysterectomy volume (reference ≥21 cases; 1-5 cases: adjusted odds ratio, 1.73; 95% confidence interval, 1.22-2.47; 6-10 cases: adjusted odds ratio, 1.60; 95% confidence interval, 1.11-2.23) were associated with perioperative complications. Use of minimally invasive hysterectomy for benign indications remains variable, with most patients undergoing open, more morbid procedures. Older and black patients and smaller hospitals are associated with open hysterectomy. Patient race and payer status, hysterectomy approach, and surgeon volume were associated with perioperative complications. Hysterectomies performed for benign indications by high-volume surgeons or by minimally invasive techniques may represent an opportunity to reduce preventable harm. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Production of biomass, polysaccharides, and ganoderic acid using non-conventional carbon sources under submerged culture of the Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.:Fr.)P. Karst. (higher Basidiomycetes).

    PubMed

    Zapata, Paola; Rojas, Diego; Atehortúa, Lucía

    2012-01-01

    The effect of different non-conventional carbon sources was studied in the submerged culture of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum, for simultaneous production of mycelial biomass, bioactive ganoderic acid, and polysaccharides, in less time, using non-conventional carbon sources to minimize the high costs of current culture media. The optimal medium composition was defined as (g/L): 50 of barley flour, 0.2 of KH2PO4, 0.1 of MgSO4ⁱ7H2O, and 1 NH4Cl. Cultivated under this complex culture medium, the mycelial biomass production was 23.49 ± 0.37 g/L; the extracellular polysaccharides production was 2.72 ± 0.11 g/L; the intracellular polysaccharides production was 2.22 ± 0.06 g/L; the ganoderic acids production was 299.67 ± 11.63 mg/L. One liter of culture medium developed in this project was priced at USD $ 0.11 if barley flour is used as carbon source or $ 0.13 with oat flour in order to get a good amount of products of interest.

  11. Identification of a laccase from Ganoderma lucidum CBS 229.93 having potential for enhancing cellulase catalyzed lignocellulose degradation.

    PubMed

    Sitarz, Anna K; Mikkelsen, Jørn D; Højrup, Peter; Meyer, Anne S

    2013-12-10

    Based on a differential pre-screening of 44 white-rot fungi on a lignocellulose-supplemented minimal medium, four basidiomycetes were selected for further study: Ganoderma lucidum, Polyporus brumalis, Polyporus ciliatus and Trametes versicolor. Only G. lucidum was able to grow vividly on malt extract or minimal media supplemented with alkali lignin. When grown on malt extract or minimal medium supplemented with lignocellulose (sugar cane bagasse), the crude G. lucidum protein extract exhibited high laccase activity, ∼3U/mL toward syringaldazine. This activity was 13-17 fold higher than the corresponding activities of the crude protein extracts of P. brumalis, P. ciliatus and T. versicolor. Native PAGE electrophoresis of the crude G. lucidum extract confirmed the presence of an active laccase. The G. lucidum laccase had a molecular weight of ∼62.5kDa, and a Km value of 0.107mM (determined on ABTS). A partial amino acid sequence analysis of four short de novo sequenced peptides, defined after trypsin digest analysis using MALDI-TOF MS/MS analysis, revealed 64-100% homology to sequences in related laccases in the UniProt database, but also indicated that certain sequence stretches had low homology. Addition of the laccase-rich G. lucidum broth to lignocellulosic biomass (pretreated sugar cane bagasse) together with a state-of-the-art cellulase enzyme preparation (Cellic™CTec1) produced significantly increased cellulolytic yields, which were also better than those obtained with a T. versicolor laccase addition, indicating that the laccase from G. lucidum has unique properties that may be momentous in lignocellulosic biomass conversion. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Induction of L-phenylalanine ammonia-lyase during utilization of phenylalanine as a carbon or nitrogen source in Rhodotorula glutinis.

    PubMed Central

    Marusich, W C; Jensen, R A; Zamir, L O

    1981-01-01

    Rhodotorula glutinis is a convenient source of L-phenylalanine ammonia-lyase, an enzyme that is useful as a biochemical reagent in the assay of L-phenylalanine. There have been previous descriptions of induced lyase production in complex medium where induction occurs late in exponential growth, suggesting a role in secondary metabolism such as is the case in higher plants. A higher specific activity of L-phenylalanine ammonia-lyase (sixfold higher than a complex medium) can be obtained during midexponential growth in a defined medium containing L-phenylalanine as the sole source of carbon. L-Phenylalanine will also induce lyase synthesis during exponential growth in minimal in which L-phenylalanine is the sole source of nitrogen. The appearance of lyase in complex medium supplemented with L-phenylalanine is probably triggered fortuitously by exhaustion late in growth of a prime source of nitrogen. In this study, R. glutinis appeared to express a single lyase enzyme, regardless of whether induction was nitrogen signaled or carbon signaled. Thin-layer chromatographic analysis of ether extracts prepared from cultures induced with doubly labeled (U-14C; ring-4-3H) L-phenylalanine provided evidence of a catabolic sequence containing cinnamic acid, benzoic acid, and 4-hydroxybenzoic acid as degradative intermediates. 3,4-Dihydroxybenzoic acid was not identified as a catabolic intermediate. PMID:7195398

  13. Targeting the expression of glutathione- and sulfate-dependent detoxification enzymes in HepG2 cells by oxygen in minimal and amino acid enriched medium.

    PubMed

    Usarek, Ewa; Graboń, Wojciech; Kaźmierczak, Beata; Barańczyk-Kuźma, Anna

    2016-02-01

    Cancer cells exhibit specific metabolism allowing them to survive and proliferate in various oxygen conditions and nutrients' availability. Hepatocytes are highly active metabolically and thus very sensitive to hypoxia. The purpose of the study was to investigate the effect of oxygen on the expression of phase II detoxification enzymes in hepatocellular carcinoma cells (HepG2) cultured in minimal and rich media (with nonessential amino acids and GSH). The cells were cultured at 1% hypoxia, 10% tissue normoxia, and 21% atmospheric normoxia. The total cell count was determined by trypan blue exclusion dye and the expression on mRNA level by RT-PCR. The result indicated that the expression of glutathione-dependent enzymes (GSTA, M, P, and GPX2) was sensitive to oxygen and medium type. At 1% hypoxia the enzyme expression (with the exception of GSTA) was higher in minimal compared to rich medium, whereas at 10% normoxia it was higher in the rich medium. The expression was oxygen-dependent in both types of medium. Among phenol sulfotransferase SULT1A1 was not sensitive to studied factors, whereas the expression of SULT1A3 was depended on oxygen only in minimal medium. It can be concluded that in HepG2 cells, the detoxification by conjugation with glutathione and, to a lower extent with sulfate, may be affected by hypoxia and/or limited nutrients' availability. Besides, because the data obtained at 10% oxygen significantly differ from those at 21%, the comparative studies on hypoxia should be performed in relation to 10% but not 21% oxygen. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. A defined medium for Leishmania culture allows definition of essential amino acids.

    PubMed

    Nayak, Archana; Akpunarlieva, Snezhana; Barrett, Michael; Burchmore, Richard

    2018-02-01

    Axenic culture of Leishmania is generally performed in rich, serum-supplemented media which sustain robust growth over multiple passages. The use of such undefined media, however, obscures proteomic analyses and confounds the study of metabolism. We have established a simple, defined culture medium that supports the sustained growth of promastigotes over multiple passages and which yields parasites that have similar infectivity to macrophages to parasites grown in a conventional semi-defined medium. We have exploited this medium to investigate the amino acid requirements of promastigotes in culture and have found that phenylalanine, tryptophan, arginine, leucine, lysine and valine are essential for viability in culture. Most of the 20 proteogenic amino acids promote growth of Leishmania promastigotes, with the exception of alanine, asparagine, and glycine. This defined medium will be useful for further studies of promastigote substrate requirements, and will facilitate future proteomic and metabolomic analyses. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PRINTED LABELS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  16. Modification of the Technical Properties of Lactobacillus johnsonii NCC 533 by Supplementing the Growth Medium with Unsaturated Fatty Acids ▿

    PubMed Central

    Muller, J. A.; Ross, R. P.; Sybesma, W. F. H.; Fitzgerald, G. F.; Stanton, C.

    2011-01-01

    The aim of this study was to investigate the influence of supplementing growth medium with unsaturated fatty acids on the technical properties of the probiotic strain Lactobacillus johnsonii NCC 533, such as heat and acid tolerance, and inhibition of Salmonella enterica serovar Typhimurium infection. Our results showed that the membrane composition and morphology of L. johnsonii NCC 533 were significantly changed by supplementing a minimal Lactobacillus medium with oleic, linoleic, and linolenic acids. The ratio of saturated to unsaturated plus cyclic fatty acids in the bacterial membrane decreased by almost 2-fold when minimal medium was supplemented with unsaturated fatty acids (10 μg/ml). The subsequent acid and heat tolerance of L. johnsonii decreased by 6- and 20-fold when the strain was grown in the presence of linoleic and linolenic acids, respectively, compared with growth in oleic acid (all at 10 μg/ml). Following acid exposure, significantly higher (P < 0.05) oleic acid content was detected in the membrane when growth medium was supplemented with linoleic or linolenic acid, indicating that saturation of the membrane fatty acids occurred during acid stress. Cell integrity was determined in real time during stressed conditions using a fluorescent viability kit in combination with flow cytometric analysis. Following heat shock (at 62.5°C for 5 min), L. johnsonii was unable to form colonies; however, 60% of the bacteria showed no cell integrity loss, which could indicate that the elevated heat inactivated vital processes within the cell, rendering it incapable of replication. Furthermore, L. johnsonii grown in fatty acid-enriched minimal medium had different adhesion properties and caused a 2-fold decrease in S. enterica serovar Typhimurium UK1-lux invasion of HT-29 epithelial cells compared with bacteria grown in minimal medium alone. This could be related to changes in the hydrophobicity and fluidity of the membrane. Our study shows that technical properties underlying probiotic survivability can be affected by nutrient composition of the growth medium. PMID:21821758

  17. Modification of the technical properties of Lactobacillus johnsonii NCC 533 by supplementing the growth medium with unsaturated fatty acids.

    PubMed

    Muller, J A; Ross, R P; Sybesma, W F H; Fitzgerald, G F; Stanton, C

    2011-10-01

    The aim of this study was to investigate the influence of supplementing growth medium with unsaturated fatty acids on the technical properties of the probiotic strain Lactobacillus johnsonii NCC 533, such as heat and acid tolerance, and inhibition of Salmonella enterica serovar Typhimurium infection. Our results showed that the membrane composition and morphology of L. johnsonii NCC 533 were significantly changed by supplementing a minimal Lactobacillus medium with oleic, linoleic, and linolenic acids. The ratio of saturated to unsaturated plus cyclic fatty acids in the bacterial membrane decreased by almost 2-fold when minimal medium was supplemented with unsaturated fatty acids (10 μg/ml). The subsequent acid and heat tolerance of L. johnsonii decreased by 6- and 20-fold when the strain was grown in the presence of linoleic and linolenic acids, respectively, compared with growth in oleic acid (all at 10 μg/ml). Following acid exposure, significantly higher (P < 0.05) oleic acid content was detected in the membrane when growth medium was supplemented with linoleic or linolenic acid, indicating that saturation of the membrane fatty acids occurred during acid stress. Cell integrity was determined in real time during stressed conditions using a fluorescent viability kit in combination with flow cytometric analysis. Following heat shock (at 62.5°C for 5 min), L. johnsonii was unable to form colonies; however, 60% of the bacteria showed no cell integrity loss, which could indicate that the elevated heat inactivated vital processes within the cell, rendering it incapable of replication. Furthermore, L. johnsonii grown in fatty acid-enriched minimal medium had different adhesion properties and caused a 2-fold decrease in S. enterica serovar Typhimurium UK1-lux invasion of HT-29 epithelial cells compared with bacteria grown in minimal medium alone. This could be related to changes in the hydrophobicity and fluidity of the membrane. Our study shows that technical properties underlying probiotic survivability can be affected by nutrient composition of the growth medium.

  18. Greedy algorithms in disordered systems

    NASA Astrophysics Data System (ADS)

    Duxbury, P. M.; Dobrin, R.

    1999-08-01

    We discuss search, minimal path and minimal spanning tree algorithms and their applications to disordered systems. Greedy algorithms solve these problems exactly, and are related to extremal dynamics in physics. Minimal cost path (Dijkstra) and minimal cost spanning tree (Prim) algorithms provide extremal dynamics for a polymer in a random medium (the KPZ universality class) and invasion percolation (without trapping) respectively.

  19. Chemically defined medium for cultivation of several epiphytic and phytopathogenic spiroplasmas.

    PubMed

    Lee, I M; Davis, R E

    1983-12-01

    A chemically defined medium, LD82, was formulated for in vitro cultivation of spiroplasmas. Medium LD82 supported good growth for four epiphytic and insect-pathogenic spiroplasmas, Spiroplasma floricola 23-6, Spiroplasma sp. strain SR3, Spiroplasma sp. strain brevi, and Spiroplasma sp. strain AS576, and of the phytopathogenic spiroplasmas Spiroplasma citri Maroc R8A2 and PC1. Titers of all six strains grown in defined medium LD82 reached 2.0 x 10 to 6.0 x 10 CFU/ml of culture. All spiroplasma strains tested formed colonies readily on agar medium LD82. None of the spiroplasmas formed typical fried-egg colonies. All formed diffuse colonies, but the forms of colonies differed somewhat among the spiroplasma strains. In preliminary studies of nutritional requirements, phospholipids slightly enhanced the growth of the epiphytic and insect-pathogenic strains in medium LD82 and were found essential for good growth of S. citri.

  20. Fatty acid and sterol composition of three phytomonas species.

    PubMed

    Nakamura, C V; Waldow, L; Pelegrinello, S R; Ueda-Nakamura, T; Filho, B A; Filho, B P

    1999-01-01

    Fatty acid and sterol analysis were performed on Phytomonas serpens and Phytomonas sp. grown in chemically defined and complex medium, and P. françai cultivated in complex medium. The three species of the genus Phytomonas had qualitatively identical fatty acid patterns. Oleic, linoleic, and linolenic were the major unsaturated fatty acids. Miristic and stearic were the major saturated fatty acids. Ergosterol was the only sterol isolated from Phytmonas sp. and P. serpens grown in a sterol-free medium, indicating that it was synthesized de novo. When P. françai that does not grow in defined medium was cultivated in a complex medium, cholesterol was the only sterol detected. The fatty acids and sterol isolated from Phytomonas sp. and P. serpens grown in a chemically defined lipid-free medium indicated that they were able to biosynthesize fatty acids and ergosterol from acetate or from acetate precursors such as glucose or threonine.

  1. Waste Minimization Assessment for Multilayered Printed Circuit Board Manufacturing

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manu facturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at s...

  2. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A PAINT MANUFACTURING PLANT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  3. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF REFURBISHED RAILCAR ASSEMBLIES

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected ...

  4. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PROTOTYPE PRINTED CIRCUIT BOARDS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  5. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF CAN-MANUFACTURING EQUIPMENT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but who lack the expertise to do so. aste Minimization Assessment Centers (WMACs) were established at ...

  6. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF SPEED REDUCTION EQUIPMENT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  7. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF CUSTOM MOLDED PLASTIC PRODUCTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected ...

  8. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A BUMPER REFINISHING PLANT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  9. Fructose-1,6-bisphosphate aldolase (class II) is the primary site of nickel toxicity in Escherichia coli.

    PubMed

    Macomber, Lee; Elsey, Scott P; Hausinger, Robert P

    2011-12-01

    Nickel is toxic to all forms of life, but the mechanisms of cell damage are unknown. Indeed, environmentally relevant nickel levels (8 µM) inhibit wild-type Escherichia coli growth on glucose minimal medium. The same concentration of nickel also inhibits growth on fructose, but not succinate, lactate or glycerol; these results suggest that fructose-1,6-bisphosphate aldolase (FbaA) is a target of nickel toxicity. Cells stressed by 8 µM Ni(II) for 20 min lost 75% of their FbaA activity, demonstrating that FbaA is inactivated during nickel stress. Furthermore, overexpression of fbaA restored growth of an rcnA mutant in glucose minimal medium supplemented with 4 µM Ni(II), thus confirming that FbaA is a primary target of nickel toxicity. This class II aldolase has an active site zinc and a non-catalytic zinc nearby. Purified FbaA lost 80 % of its activity within 2 min when challenged with 8 µM Ni(II). Nickel-challenged FbaA lost 0.8 zinc and gained 0.8 nickel per inactivated monomer. FbaA mutants (D144A and E174A) affecting the non-catalytic zinc were resistant to nickel inhibition. These results define the primary site of nickel toxicity in E. coli as the class II aldolase FbaA through binding to the non-catalytic zinc site. © 2011 Blackwell Publishing Ltd.

  10. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTUERE OF OUTDOOR ILLUMINATED SIGNS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  11. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF SHEET METAL COMPONENTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization ssessment Cente...

  12. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF BRAZED ALUMINUM OIL COOLERS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  13. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF ALUMINUM CANS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  14. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PRINTED CIRCUIT BOARDS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  15. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF IRON CASTINGS AND FABRICATED SHEET METAL PARTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  16. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION FOR A MANUFACTURER OF ALUMINUM AND STEEL PARTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization Assessment Cent...

  17. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF ALUMINUM AND STEEL PARTS

    EPA Science Inventory

    The U.S.Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-sized manufacturers who want to minimize their generation of waste but who lack the expertise to do so. In an effort to assist these manufacturers, Waste Minimization Assessment Ce...

  18. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PENNY BLANKS AND ZINC PRODUCTS

    EPA Science Inventory

    The U.S. EnvIronmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. aste Minimization Assessment Centers (WMACs) were established at selected u...

  19. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A METAL PARTS COATING PLANT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  20. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF CORN SYRUP AND CORN STARCH

    EPA Science Inventory

    The U.S.Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their geneation of waste but who lack the expertise to do so. In an effort to assist these manufacturers, Waste Minimization Assessment Cent...

  1. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF CUTTING AND WELDING EQUIPMENT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot program to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so in an effort to assist these manufacturers Waste Minimization Assessment Cent...

  2. WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF SILICON-CONTROLLED RECTIFIERS AND SCHOTTKY RECTIFIERS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. In an effort to assist these manufacturers Waste Minimization Assessment Ce...

  3. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF REBUILT RAILWAY CARS AND COMPONENTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium- size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at se...

  4. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF PRINTED PLASTIC BAGS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established ...

  5. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION FOR A MANUFACTURER OF COMPRESSED AIR EQUIPMENT COMPONENTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  6. Growth yields and fermentation balance of Bacteroides fragilis cultured in glucose-enriched medium.

    PubMed

    Frantz, J C; McCallum, R E

    1979-03-01

    Bacteroides fragilis is an obligate anaerobic bacterium classified with the gram-negative, non-sporeforming bacilli and is the Bacteroides species most frequently isolated from human infections. In the present study, experiments were designed to investigate growth characteristics of B. fragilis in a complex medium. In a minimal defined medium, which was employed for comparison purposes, B. fragilis grew with a generation time of 2 h. Growth of the organism in glucose-enriched medium used in the present study was superior. Maximum generation time was 60 min. Total and viable cells (colony-forming units) were 8.9 x 10(9) and 2.1 x 10(9), respectively, at maximum measurable growth. The molar growth yield (Ym) was 51.5. Growth yields were found to reach a maximum 2 to 3 h before maximum growth and to vary with respect to the phase of growth. Estimates of the fermentation products indicated that glucose was the sole energy substrate. Major products included acetic acid, propionic acid, lactic acid, and succinic acid. Other products included ethyl alcohol, pyruvic acid, and fumaric acid. No attempt was made to recover CO2 or formic acid. The OR balances from two experiments were 0.013 and -0.093 and the respective carbon recoveries were 6.268 and 6.241. The results of the present study show that B. fragilis is capable of rapid rates of growth in vitro by using glucose as the sole energy source.

  7. Stability of pathogenic colony types of Neisseria gonorrhoeae in liquid culture by using the parameters of colonial morphology and deoxyribonucleic acid transformation.

    PubMed Central

    La Scolea, L J; Dul, M J; Young, F E

    1975-01-01

    This investigation describes the surveillance of the colonial stability of the pathogenic type 1 from the gonococcal strain F62 to the nonvirulent types 3 and 4 in different liquid media. The maintenance of the colony types was monitored by the parameters of colonial morphology and deoxyribonucleic acid-mediated transformation. During growth in a complex medium, Mueller-Hinton broth, only 46.7% of the gonococcal population remained as type 1 after 12 h. The greatest change in the type 1 colony-forming units correlated with the decline in viable count. The conversion process could not be prevented by the continual maintenance of the gonococcus in logarithmic growth. The frequency of transformation from PRO(minus) (proline) to PRO(plus) was proportional to this decrease in type 1 colony-forming units. In contrast to Mueller-Hinton medium, the chemically defined minimal medium Gonococcal Genetic Medium (GGM) was capable of maintaining approximately 90% of the gonococcal population in the type 1 colonial form after 16 h of growth, despite a decrease in the viable count. Although the percentage of type 1 appeared to remain constant in GGM, the apparent transformation frequency increased approximately 24-fold from 0 to 12 h of growth. GGM appears to stimulate or maintain competence, as evidenced by an eightfold increase in transformation when cells are exposed to deoxyribonucleic acid in GGM as compared to Mueller-Hinton. PMID:809469

  8. Automating the selection of standard parallels for conic map projections

    NASA Astrophysics Data System (ADS)

    Šavriǒ, Bojan; Jenny, Bernhard

    2016-05-01

    Conic map projections are appropriate for mapping regions at medium and large scales with east-west extents at intermediate latitudes. Conic projections are appropriate for these cases because they show the mapped area with less distortion than other projections. In order to minimize the distortion of the mapped area, the two standard parallels of conic projections need to be selected carefully. Rules of thumb exist for placing the standard parallels based on the width-to-height ratio of the map. These rules of thumb are simple to apply, but do not result in maps with minimum distortion. There also exist more sophisticated methods that determine standard parallels such that distortion in the mapped area is minimized. These methods are computationally expensive and cannot be used for real-time web mapping and GIS applications where the projection is adjusted automatically to the displayed area. This article presents a polynomial model that quickly provides the standard parallels for the three most common conic map projections: the Albers equal-area, the Lambert conformal, and the equidistant conic projection. The model defines the standard parallels with polynomial expressions based on the spatial extent of the mapped area. The spatial extent is defined by the length of the mapped central meridian segment, the central latitude of the displayed area, and the width-to-height ratio of the map. The polynomial model was derived from 3825 maps-each with a different spatial extent and computationally determined standard parallels that minimize the mean scale distortion index. The resulting model is computationally simple and can be used for the automatic selection of the standard parallels of conic map projections in GIS software and web mapping applications.

  9. Mixing blade system for high-resistance media

    DOEpatents

    Kronberg, James W.

    1991-01-01

    A blade system for stirring and agitating a medium, comprising a shaft bearing a plurality of paddles, each having a different geometry and each having approximately the same rotational moment. The geometrically different paddles sweep through different volumes of the medium to minimize shear zone development and maximize the strength of the system with respect to medium-induced stress.

  10. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF HEATING, VENTILATING, AND AIR CONDITIONING EQUIPMENT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small- and medium-size manufacturers who want to minimize their generation of hazardous waste but lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at sel...

  11. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF BASEBALL BATS AND GOLF CLUBS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. aste Minimization Assessment Centers (WMACS) were established at selected un...

  12. ENVIRONMENTAL RESEARCH BRIEF: WASTE MINIMIZATION ASSESSMENT FOR A MANUFACTURER OF IRON CASTINGS AND FABRICATED SHEET METAL PARTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expense to do so. aste Minimization Assessment Centers (WMACS) were established at selected univ...

  13. Development and validation of a minimal growth medium for recycling Chlorella vulgaris culture.

    PubMed

    Hadj-Romdhane, F; Jaouen, P; Pruvost, J; Grizeau, D; Van Vooren, G; Bourseau, P

    2012-11-01

    When microalgae culture medium is recycled, ions (e.g. Na(+), K(+), Ca(2+)) that were not assimilated by the microalgae accumulate in the medium. Therefore, a growth medium (HAMGM) was developed that included ions that were more easily assimilated by Chlorella vulgaris, such as ammonium one (NH(4)(+)). Recycling performance was studied by carrying out 8-week continuous cultivation of C. vulgaris with recycled HAMGM medium. No loss of biomass productivity was observed compared to culture in a conventional medium, and accumulation of ions over time was negligible. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Mixing blade system for high-resistance media

    DOEpatents

    Kronberg, J.W.

    1991-07-09

    A blade system is described for stirring and agitating a medium, comprising a shaft bearing a plurality of paddles, each having a different geometry and each having approximately the same rotational moment. The geometrically different paddles sweep through different volumes of the medium to minimize shear zone development and maximize the strength of the system with respect to medium-induced stress. 6 figures.

  15. Planning for the Impacts of Highway Relief Routes on Small- and Medium-Size Communities

    DOT National Transportation Integrated Search

    2001-03-01

    This report explores possible strategies for minimizing the negative impacts and maximizing the positive impacts of highway relief routes on small- and medium-size communities in Texas. Planning strategies are identified through a : literature search...

  16. Carbohydrate Metabolism and Carbon Fixation in Roseobacter denitrificans OCh114

    PubMed Central

    Tang, Kuo-Hsiang; Feng, Xueyang; Tang, Yinjie J.; Blankenship, Robert E.

    2009-01-01

    The Roseobacter clade of aerobic marine proteobacteria, which compose 10–25% of the total marine bacterial community, has been reported to fix CO2, although it has not been determined what pathway is involved. In this study, we report the first metabolic studies on carbohydrate utilization, CO2 assimilation, and amino acid biosynthesis in the phototrophic Roseobacter clade bacterium Roseobacter denitrificans OCh114. We develop a new minimal medium containing defined carbon source(s), in which the requirements of yeast extract reported previously for the growth of R. denitrificans can be replaced by vitamin B12 (cyanocobalamin). Tracer experiments were carried out in R. denitrificans grown in a newly developed minimal medium containing isotopically labeled pyruvate, glucose or bicarbonate as a single carbon source or in combination. Through measurements of 13C-isotopomer labeling patterns in protein-derived amino acids, gene expression profiles, and enzymatic activity assays, we report that: (1) R. denitrificans uses the anaplerotic pathways mainly via the malic enzyme to fix 10–15% of protein carbon from CO2; (2) R. denitrificans employs the Entner-Doudoroff (ED) pathway for carbohydrate metabolism and the non-oxidative pentose phosphate pathway for the biosynthesis of histidine, ATP, and coenzymes; (3) the Embden-Meyerhof-Parnas (EMP, glycolysis) pathway is not active and the enzymatic activity of 6-phosphofructokinase (PFK) cannot be detected in R. denitrificans; and (4) isoleucine can be synthesized from both threonine-dependent (20% total flux) and citramalate-dependent (80% total flux) pathways using pyruvate as the sole carbon source. PMID:19794911

  17. Water reuse in the l-lysine fermentation process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hsiao, T.Y.; Glatz, C.E.

    1996-02-05

    L-Lysine is produced commercially by fermentation. As is typical for fermentation processes, a large amount of liquid waste is generated. To minimize the waste, which is mostly the broth effluent from the cation exchange column used for l-lysine recovery, the authors investigated a strategy of recycling a large fraction of this broth effluent to the subsequent fermentation. This was done on a lab-scale process with Corynebacterium glutamicum ATCC 21253 as the l-lysine-producing organisms. Broth effluent from a fermentation in a defined medium was able to replace 75% of the water for the subsequent batch; this recycle ratio was maintained formore » 3 sequential batches without affecting cell mass and l-lysine production. Broth effluent was recycled at 50% recycle ratio in a fermentation in a complex medium containing beet molasses. The first recycle batch had an 8% lower final l-lysine level, but 8% higher maximum cell mass. In addition to reducing the volume of liquid waste, this recycle strategy has the additional advantage of utilizing the ammonium desorbed from the ion-exchange column as a nitrogen source in the recycle fermentation. The major problem of recycling the effluent from the complex medium was in the cation-exchange operation, where column capacity was 17% lower for the recycle batch. The loss of column capacity probably results from the buildup of cations competing with l-lysine for binding.« less

  18. Tunable semiconductor lasers

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, Shervin (Inventor); Vanzyl, Jakob J. (Inventor); Yariv, Amnon (Inventor)

    2006-01-01

    Tunable semiconductor lasers are disclosed requiring minimized coupling regions. Multiple laser embodiments employ ring resonators or ring resonator pairs using only a single coupling region with the gain medium are detailed. Tuning can be performed by changing the phase of the coupling coefficient between the gain medium and a ring resonator of the laser. Another embodiment provides a tunable laser including two Mach-Zehnder interferometers in series and a reflector coupled to a gain medium.

  19. Ketoconazole inhibits Malassezia furfur morphogenesis in vitro under filamentation optimized conditions.

    PubMed

    Youngchim, Sirida; Nosanchuk, Joshua D; Chongkae, Siriporn; Vanittanokom, Nongnuch

    2017-01-01

    Malassezia furfur, a constituent of the normal human skin flora, is an etiological agent of pityriasis versicolor, which represents one of the most common human skin diseases. Under certain conditions, both exogenous and endogenous, the fungus can transition from a yeast form to a pathogenic mycelial form. To develop a standardized medium for reproducible production of the mycelial form of M. furfur to develop and optimize susceptibility testing for this pathogen, we examined and characterized variables, including kojic acid and glycine concentration, agar percentage, and pH, to generate a chemically defined minimal medium on which specific inoculums of M. furfur generated the most robust filamentation. Next, we examined the capacity of ketoconazole to inhibit the formation of M. furfur mycelial form. Both low and high, 0.01, 0.05 and 0.1 µg/ml concentrations of ketoconazole significantly inhibited filamentation at 11.9, 54.5 and 86.7%, respectively. Although ketoconazole can have a direct antifungal effect on both M. furfur yeast and mycelial cells, ketoconazole also has a dramatic impact on suppressing morphogenesis. Since mycelia typified the pathogenic form of Malassezia infection, the capacity of ketoconazole to block morphogenesis may represent an additional important effect of the antifungal.

  20. Control of Growth Rate by Initial Substrate Concentration at Values Below Maximum Rate

    PubMed Central

    Gaudy, Anthony F.; Obayashi, Alan; Gaudy, Elizabeth T.

    1971-01-01

    The hyperbolic relationship between specific growth rate, μ, and substrate concentration, proposed by Monod and used since as the basis for the theory of steady-state growth in continuous-flow systems, was tested experimentally in batch cultures. Use of a Flavobacterium sp. exhibiting a high saturation constant for growth in glucose minimal medium allowed direct measurement of growth rate and substrate concentration throughout the growth cycle in medium containing a rate-limiting initial concentration of glucose. Specific growth rates were also measured for a wide range of initial glucose concentrations. A plot of specific growth rate versus initial substrate concentration was found to fit the hyperbolic equation. However, the instantaneous relationship between specific growth rate and substrate concentration during growth, which is stated by the equation, was not observed. Well defined exponential growth phases were developed at initial substrate concentrations below that required for support of the maximum exponential growth rate and a constant doubling time was maintained until 50% of the substrate had been used. It is suggested that the external substrate concentration initially present “sets” the specific growth rate by establishing a steady-state internal concentration of substrate, possibly through control of the number of permeation sites. PMID:5137579

  1. Tricarboxylic acid cycle without malate dehydrogenase in Streptomyces coelicolor M-145.

    PubMed

    Takahashi-Íñiguez, Tóshiko; Barrios-Hernández, Joana; Rodríguez-Maldonado, Marion; Flores, María Elena

    2018-06-23

    The oxidation of malate to oxaloacetate is catalysed only by a nicotinamide adenine dinucleotide-dependent malate dehydrogenase encoded by SCO4827 in Streptomyces coelicolor. A mutant lacking the malate dehydrogenase gene was isolated and no enzymatic activity was detected. As expected, the ∆mdh mutant was unable to grow on malate as the sole carbon source. However, the mutant grew less in minimal medium with glucose and there was a delay of 36 h. The same behaviour was observed when the mutant was grown on minimal medium with casamino acids or glycerol. For unknown reasons, the mutant was not able to grow in YEME medium with glucose. The deficiency of malate dehydrogenase affected the expression of the isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase genes, decreasing the expression of both genes by approximately two- to threefold.

  2. Effect of stress induced by suboptimal growth factors on survival of Escherichia coli O157:H7.

    PubMed

    Uyttendaele, M; Taverniers, I; Debevere, J

    2001-05-21

    This study investigated the growth and survival of E. coli O157:H7 exposed to a combination of suboptimal factors (22 degrees C, 7 degrees C, -18 degrees C/0.5% NaCl, 5.0% NaCl/pH 7.0, pH 5.4, pH 4.5/addition of lactic acid) in a simulation medium for red meat (beef gravy). Prolonged survival was noted as the imposed stress was more severe, and as multiple growth factors became suboptimal. At a defined temperature (7 degrees C or -18 degrees C), survival was prolonged at the more acid, more suboptimal pH (pH 4.5 > pH 5.4 > pH 7.0) while at a defined pH (pH 4.5), better survival was observed at 7 degrees C than at 22 degrees C. This suggests that application of the hurdle concept for preservation of food may inhibit outgrowth but induce prolonged survival of E. coli O157:H7 in minimal processed foods. At both 22 degrees C and 7 degrees C, the addition of lactic acid instead of HCl to reduce pH (to pH 4.5) resulted in a more rapid decrease of E. coli O157:H7. High survival was observed in beef gravy, pH 5.4 at -18 degrees C (simulation of frozen meat)-reduction of log 3.0 to log 1.9 after 43 days--and in beef gravy, pH 4.5 and 5% NaCl at 7 degrees C (simulation of a fermented dried meat product kept in refrigeration)--less than 1 log reduction in 43 days. In these circumstances, however, a high degree of sublethal damage of the bacterial cells was noted. The degree of sublethal damage can be estimated from the difference in recovery of the pathogen on the non-selective TSA medium and the selective SMAC medium.

  3. The observed life cycle of a baroclinic instability

    NASA Technical Reports Server (NTRS)

    Randel, W. J.; Stanford, J. L.

    1985-01-01

    Medium-scale waves (zonal wavenumbers 4-7) frequently dominate Southern Hemisphere summer circulation patterns. Randel and Stanford have studied the dynamics of these features, demonstrating that the medium-scale waves result from baroclinic excitation and exhibit well-defined life cycles. This study details the evolution of the medium-scale waves during a particular life cycle. The specific case chosen exhibits a high degree of zonal symmetry, prompting study based upon zonally averaged diagnostics. An analysis of the medium-scale wave energetics reveals a well-defined life cycle of baroclinic growth, maturity, and barotropic decay. Eliassen-Palm flux diagrams detail the daily wave structure and its interaction with the zonally-averaged flow.

  4. Generalized minimal principle for rotor filaments.

    PubMed

    Dierckx, Hans; Wellner, Marcel; Bernus, Olivier; Verschelde, Henri

    2015-05-01

    To a reaction-diffusion medium with an inhomogeneous anisotropic diffusion tensor D, we add a fourth spatial dimension such that the determinant of the diffusion tensor is constant in four dimensions. We propose a generalized minimal principle for rotor filaments, stating that the scroll wave filament strives to minimize its surface area in the higher-dimensional space. As a consequence, stationary scroll wave filaments in the original 3D medium are geodesic curves with respect to the metric tensor G=det(D)D(-1). The theory is confirmed by numerical simulations for positive and negative filament tension and a model with a non-stationary spiral core. We conclude that filaments in cardiac tissue with positive tension preferentially reside or anchor in regions where cardiac cells are less interconnected, such as portions of the cardiac wall with a large number of cleavage planes.

  5. Cladding for transverse-pumped solid-state laser

    NASA Technical Reports Server (NTRS)

    Byer, Robert L. (Inventor); Fan, Tso Y. (Inventor)

    1989-01-01

    In a transverse pumped, solid state laser, a nonabsorptive cladding surrounds a gain medium. A single tranverse mode, namely the Transverse Electromagnetic (TEM) sub 00 mode, is provided. The TEM sub 00 model has a cross sectional diameter greater than a transverse dimension of the gain medium but less than a transverse dimension of the cladding. The required size of the gain medium is minimized while a threshold for laser output is lowered.

  6. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF LOCKING DEVICES (EPA/600/S-95/013)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  7. ENVIRONMENTAL RESEARCH BRIEF: POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF FOOD SERVICE EQUIPMENT

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization Assessment Cent...

  8. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF BOURBON WHISKEY (EPA/600/S-95/010

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  9. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF POWER SUPPLIES (EPA/600/S-95/025)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  10. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF METAL FASTENERS (EPA/600/S-95/016)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  11. ENVIRONMENTAL RESEARCH BRIEF: POLLUTION PREVENTION FOR A MANUFACTURER OF METAL FASTENERS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization Assessment Cent...

  12. ENVIRONMENTAL RESEARCH BRIEF: POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF REBUILT INDUSTRIAL CRANKSHAFTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization Assessment Cent...

  13. CO.sub.2 laser

    DOEpatents

    Rink, John P.

    1977-01-01

    The disclosure relates to a pulsed gas laser comprising an optical resonant cavity, a CO.sub.2 lasing medium, structure for containing the CO.sub.2 lasing medium within the optical cavity and a device for causing a population inversion in the lasing medium, with a novel improvement comprising structure for causing a laser pulse comprising a wavelength in the near 14 .mu.m and near 16 .mu.m range. The structure for cooling the CO.sub.2 lasing medium to less than about -40.degree. C as well is a structure for pumping the maximum inversion of CO.sub.2 molecules within the lasing medium by minimizing the population in the 010 level.

  14. Inferring the Minimal Genome of Mesoplasma florum by Comparative Genomics and Transposon Mutagenesis.

    PubMed

    Baby, Vincent; Lachance, Jean-Christophe; Gagnon, Jules; Lucier, Jean-François; Matteau, Dominick; Knight, Tom; Rodrigue, Sébastien

    2018-01-01

    The creation and comparison of minimal genomes will help better define the most fundamental mechanisms supporting life. Mesoplasma florum is a near-minimal, fast-growing, nonpathogenic bacterium potentially amenable to genome reduction efforts. In a comparative genomic study of 13 M. florum strains, including 11 newly sequenced genomes, we have identified the core genome and open pangenome of this species. Our results show that all of the strains have approximately 80% of their gene content in common. Of the remaining 20%, 17% of the genes were found in multiple strains and 3% were unique to any given strain. On the basis of random transposon mutagenesis, we also estimated that ~290 out of 720 genes are essential for M. florum L1 in rich medium. We next evaluated different genome reduction scenarios for M. florum L1 by using gene conservation and essentiality data, as well as comparisons with the first working approximation of a minimal organism, Mycoplasma mycoides JCVI-syn3.0. Our results suggest that 409 of the 473 M. mycoides JCVI-syn3.0 genes have orthologs in M. florum L1. Conversely, 57 putatively essential M. florum L1 genes have no homolog in M. mycoides JCVI-syn3.0. This suggests differences in minimal genome compositions, even for these evolutionarily closely related bacteria. IMPORTANCE The last years have witnessed the development of whole-genome cloning and transplantation methods and the complete synthesis of entire chromosomes. Recently, the first minimal cell, Mycoplasma mycoides JCVI-syn3.0, was created. Despite these milestone achievements, several questions remain to be answered. For example, is the composition of minimal genomes virtually identical in phylogenetically related species? On the basis of comparative genomics and transposon mutagenesis, we investigated this question by using an alternative model, Mesoplasma florum, that is also amenable to genome reduction efforts. Our results suggest that the creation of additional minimal genomes could help reveal different gene compositions and strategies that can support life, even within closely related species.

  15. Correlation of endothelin-1 concentration and angiotensin-converting enzyme activity with the staging of liver fibrosis.

    PubMed

    Kardum, Dusko; Fabijanić, Damir; Lukić, Anita; Romić, Zeljko; Petrovecki, Mladen; Bogdanović, Zoran; Jurić, Klara; Urek-Crncević, Marija; Banić, Marko

    2012-06-01

    Increased serum angiotensin-converting enzyme (SACE) activity and serum concentration of endothelin-1 (ET-1) were found in liver cirrhosis. We investigated a correlation between the different stages of liver fibrosis and SACE activity and serum ET-1 concentration. Seventy patients with pathohistologically established chronic liver disease were divided in three groups according to Ishak criteria for liver fibrosis: minimal fibrosis (Ishak score 0-1, n =20), medium fibrosis (Ishak score 2-5, n=20) and cirrhosis (Ishak score 6, n=30). SACE activity and ET-1 concentration were determined using commercial ELISA kits. SACE activity and ET-1 concentrations were proportional to the severity of disease, the highest being in patients with liver cirrhosis. Maximal increase in SACE activity was found between minimal and medium fibrosis while maximal increase in ET-1 concentration was revealed between medium fibrosis and cirrhosis. The analysis of the Receiver Operating Characteristic (ROC) curve for SACE activity suggested a cut-off value to separate minimal from medium fibrosis at 59.00 U/L (sensitivity 100%, specificity 64.7%). The cut-off value for serum ET-1 concentration to separate medium fibrosis from cirrhosis was 12.4 pg/mL (sensitivity 96.8%, specificity 94.4%). A positive correlation between SACE activity and ET-1 concentration was registered (Spearman's ñ = 0.438, p = 0.004). Both SACE activity and ET-1 concentration were increased in all stages of liver fibrosis. Cut-off points for SACE activity and ET-1 concentration could be a biochemical marker for the progression of fibrosis. Positive correlation between SACE activity and ET-1 concentration might indicate their interaction in the development of liver cirrhosis.

  16. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF STAINLESS STEEL PIPES AND FITTINGS (EPA/600/S-95/017)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  17. POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF FOOD SERVICE EQUIPMENT (EPA/600/S-95/026)

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. Waste Minimization Assessment Centers (WMACs) were established at selected u...

  18. ENVIRONMENTAL RESEARCH BRIEF: POLLUTION PREVENTION ASSESSMENT FOR A MANUFACTURER OF GEAR CASES FOR OUTBOARD MOTORS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has funded a pilot project to assist small and medium-size manufacturers who want to minimize their generation of waste but who lack the expertise to do so. n an effort to assist these manufacturers Waste Minimization Assessment Cent...

  19. Elimination of formate production in Clostridium thermocellum.

    PubMed

    Rydzak, Thomas; Lynd, Lee R; Guss, Adam M

    2015-09-01

    The ability of Clostridium thermocellum to rapidly degrade cellulose and ferment resulting hydrolysis products into ethanol makes it a promising platform organism for cellulosic biofuel production via consolidated bioprocessing. Currently, however, ethanol yield is far below theoretical maximum due to branched product pathways that divert carbon and electrons towards formate, H2, lactate, acetate, and secreted amino acids. To redirect carbon and electron flux away from formate, genes encoding pyruvate:formate lyase (pflB) and PFL-activating enzyme (pflA) were deleted. Formate production in the resulting Δpfl strain was eliminated and acetate production decreased by 50 % on both complex and defined medium. The growth rate of the Δpfl strain decreased by 2.9-fold on defined medium and biphasic growth was observed on complex medium. Supplementation of defined medium with 2 mM formate restored Δpfl growth rate to 80 % of the parent strain. The role of pfl in metabolic engineering strategies and C1 metabolism is discussed.

  20. Elimination of formate production in Clostridium thermocellum

    DOE PAGES

    Rydzak, Thomas; Lynd, Lee R.; Guss, Adam M.

    2015-07-11

    We study the ability of Clostridium thermocellum to rapidly degrade cellulose and ferment resulting hydrolysis products into ethanol makes it a promising platform organism for cellulosic biofuel production via consolidated bioprocessing. Currently, however, ethanol yield are far below theoretical maximum due to branched product pathways that divert carbon and electrons towards formate, H 2, lactate, acetate, and secreted amino acids. To redirect carbon and electron flux away from formate, pyruvate:formate lyase (pfl) and respective PFL-activating enzyme were deleted. Formate production in the resulting Δpfl strain was eliminated and acetate production decreased by 50% on both complex and defined medium. Growthmore » rate of Δpfl decreased by 2.9-fold on defined medium and diauxic growth was observed on complex medium. Supplementation of defined medium with 2 mM formate restored Δpfl growth rate to 80% of the parent strain. Finally, we discuss the role of pfl in metabolic engineering strategies and C 1 metabolism.« less

  1. NF-1 Dependent Gene Regulation in Drosophila Melanogaster

    DTIC Science & Technology

    2004-04-01

    standard cornmeal medium at 25oC in a humidified incubator. Flies were collected and frozen in liquid nitrogen at the same time of day to minimize...melanogaster media, strains and heat-shock conditions Flies were raised at room temperature (22–248C) on standard cornmeal medium. The Nf1 mutants Nf1P1 and

  2. Light-driven phase shifter

    DOEpatents

    Early, James W.

    1990-01-01

    A light-driven phase shifter is provided for modulating a transmission light beam. A gaseous medium such as argon is provided with electron energy states excited to populate a metastable state. A tunable dye laser is selected with a wavelength effective to deplete the metastable electron state and may be intensity modulated. The dye laser is directed through the gaseous medium to define a first optical path having an index of refraction determined by the gaseous medium having a depleted metastable electron state. A transmission laser beam is also directed through the gaseous medium to define a second optical path at least partially coincident with the first optical path. The intensity of the dye laser beam may then be varied to phase modulate the transmission laser beam.

  3. Cryopreservation of Human Pluripotent Stem Cells in Defined Medium

    PubMed Central

    Liu, Weiwei; Chen, Guokai

    2014-01-01

    This protocol describes a cryopreservation procedure using an enzyme-free dissociation method to harvest cells and preserve cells in albumin-free chemically defined E8 medium for human pluripotent stem cells (hPSCs). The dissociation by EDTA/PBS produces small cell aggregates that allow high survival efficiency in passaging and cryopreservation. The preservation in E8 medium eliminates serum or other animal products, and is suitable for the increasing demand for high quality hPSCs in translational research. In combination with the special feature of EDTA/PBS dissociation, this protocol allows efficient cryopreservation in more time-saving manner. PMID:25366897

  4. Drazepinone, a trisubstituted tetrahydronaphthofuroazepinone with herbicidal activity produced by Drechslera siccans.

    PubMed

    Evidente, Antonio; Andolfi, Anna; Vurro, Maurizio; Fracchiolla, Mariano; Zonno, Maria Chiara; Motta, Andrea

    2005-03-01

    When grown in a minimal-defined medium, a strain of Drechslera siccans, a pathogenic fungus isolated from seeds of Lolium perenne, produced phytotoxic metabolites. This strain is one of the best toxin producers among several grass pathogenic fungal strains collected and tested to find phytotoxins to be used as natural herbicides of monocot weeds. From the culture filtrates of D. siccans, we isolated a new phytotoxic trisubstituted naphthofuroazepinone, named drazepinone, and characterised it as a 3,5,12a-trimethyl-2,5,5a,12a-tetrahydro-1H-naphtho[2',3':4,5]furo[2,3-b]azepin-2-one. Assayed at 2 microg microl(-1) solution the novel metabolite proved to have broad-spectrum herbicidal properties, without antibacterial and antifungal activities, and low zootoxic activity. Its original chemical structure and the interesting biological properties make drazepinone a potential natural herbicide.

  5. Considerations, measurements and logistics associated with low-energy cyclotron decommissioning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sunderland, J. J.; Erdahl, C. E.; Bender, B. R.

    2012-12-19

    The University of Iowa's 20-year-old 17 MeV Scanditronix cyclotron underwent decommissioning in the summer of 2011. To satisfy local, state and federal regulations defining removal, transportation and long-term safe and environmentally secure disposal of the 22 ton activated cyclotron, a series of nuclear spectroscopic measurements were performed to characterize the nature and extent of proton and neutron activation of the 22-ton cyclotron, its associated targets, and the concrete wall that was demolished to remove the old cyclotron. Neutron activation of the concrete wall was minimal and below exempt concentrations resulting in standard landfill disposal. The cyclotron assessment revealed the expectedmore » array of short and medium-lived radionuclides. Subsequent calculations suggest that meaningful levels residual activity will have decayed virtually to background after 15 years, with the total residual activity of the entire cyclotron dropping below 37 MBq (1 mCi).« less

  6. Application of advanced high speed turboprop technology to future civil short-haul transport aircraft design

    NASA Technical Reports Server (NTRS)

    Conlon, J. A.; Bowles, J. V.

    1978-01-01

    With an overall goal of defining the needs and requirements for short-haul transport aircraft research and development, the objective of this paper is to determine the performance and noise impact of short-haul transport aircraft designed with an advanced turboprop propulsion system. This propulsion system features high-speed propellers that have more blades and reduced diameters. Aircraft are designed for short and medium field lengths; mission block fuel and direct operating costs (DOC) are used as performance measures. The propeller diameter was optimized to minimize DOC. Two methods are employed to estimate the weight of the acoustic treatment needed to reduce interior noise to an acceptable level. Results show decreasing gross weight, block fuel, DOC, engine size, and optimum propfan diameter with increasing field length. The choice of acoustic treatment method has a significant effect on the aircraft design.

  7. Genome-wide essential gene identification in Streptococcus sanguinis

    PubMed Central

    Xu, Ping; Ge, Xiuchun; Chen, Lei; Wang, Xiaojing; Dou, Yuetan; Xu, Jerry Z.; Patel, Jenishkumar R.; Stone, Victoria; Trinh, My; Evans, Karra; Kitten, Todd; Bonchev, Danail; Buck, Gregory A.

    2011-01-01

    A clear perception of gene essentiality in bacterial pathogens is pivotal for identifying drug targets to combat emergence of new pathogens and antibiotic-resistant bacteria, for synthetic biology, and for understanding the origins of life. We have constructed a comprehensive set of deletion mutants and systematically identified a clearly defined set of essential genes for Streptococcus sanguinis. Our results were confirmed by growing S. sanguinis in minimal medium and by double-knockout of paralogous or isozyme genes. Careful examination revealed that these essential genes were associated with only three basic categories of biological functions: maintenance of the cell envelope, energy production, and processing of genetic information. Our finding was subsequently validated in two other pathogenic streptococcal species, Streptococcus pneumoniae and Streptococcus mutans and in two other gram-positive pathogens, Bacillus subtilis and Staphylococcus aureus. Our analysis has thus led to a simplified model that permits reliable prediction of gene essentiality. PMID:22355642

  8. Extracellular accumulation of recombinant protein by Escherichia coli in a defined medium.

    PubMed

    Fu, Xiang-Yang

    2010-09-01

    Extracellular accumulation of recombinant proteins in the culture medium of Escherichia coli is desirable but difficult to obtain. The inner or cytoplasmic membrane and the outer membrane of E. coli are two barriers for releasing recombinant proteins expressed in the cytoplasm into the culture medium. Even if recombinant proteins have been exported into the periplasm, a space between the outer membrane and the inner membrane, the outer membrane remains the last barrier for their extracellular release. However, when E. coli was cultured in a particular defined medium, recombinant proteins exported into the periplasm could diffuse into the culture medium automatically. If a nonionic detergent, Triton X-100, was added in the medium, recombinant proteins expressed in the cytoplasm could also be released into the culture medium. It was then that extracellular accumulation of recombinant proteins could be obtained by exporting them into the periplasm or releasing them from the cytoplasm with Triton X-100 addition. The tactics described herein provided simple and valuable methods for achieving extracellular production of recombinant proteins in E. coli.

  9. The Effect of Radiation on the Normal and Oestrone-treated Mouse Vagina Grown in vitro

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lasnitzki, Ilse

    1961-06-01

    The effect of radiation on the differentiation of normal and oestrone- treated organ cultures of the mouse vagina was studied during growth in natural and in chemically defined medium. After explanation into either type of medium without addition of the hormone the vaginal epithelium spontaneously forms new squamous keratinising epithelium which displaces the original secretory epithelium. Addition of oestrone to the medium stimulates the growth of the new cells and hastens and increases keratin synthesis. Exposure to 200 r of x rays given one day after explanation inhibits the squamous development, suppresses keratin formation and preserves the original epithelium inmore » both normal and oestrone-treated explants grown in natural medium. Radiation of cultures kept in defined medium fails to influence the normal squamous differentiation and keratinisation. The mechanism of radiation action is discussed in the light of the differnet results obtained under the two conditions. (auth)« less

  10. Metabolomic profiling in perinatal asphyxia: a promising new field.

    PubMed

    Denihan, Niamh M; Boylan, Geraldine B; Murray, Deirdre M

    2015-01-01

    Metabolomics, the latest "omic" technology, is defined as the comprehensive study of all low molecular weight biochemicals, "metabolites" present in an organism. As a systems biology approach, metabolomics has huge potential to progress our understanding of perinatal asphyxia and neonatal hypoxic-ischaemic encephalopathy, by uniquely detecting rapid biochemical pathway alterations in response to the hypoxic environment. The study of metabolomic biomarkers in the immediate neonatal period is not a trivial task and requires a number of specific considerations, unique to this disease and population. Recruiting a clearly defined cohort requires standardised multicentre recruitment with broad inclusion criteria and the participation of a range of multidisciplinary staff. Minimally invasive biospecimen collection is a priority for biomarker discovery. Umbilical cord blood presents an ideal medium as large volumes can be easily extracted and stored and the sample is not confounded by postnatal disease progression. Pristine biobanking and phenotyping are essential to ensure the validity of metabolomic findings. This paper provides an overview of the current state of the art in the field of metabolomics in perinatal asphyxia and neonatal hypoxic-ischaemic encephalopathy. We detail the considerations required to ensure high quality sampling and analysis, to support scientific progression in this important field.

  11. Metabolomic Profiling in Perinatal Asphyxia: A Promising New Field

    PubMed Central

    Denihan, Niamh M.; Boylan, Geraldine B.; Murray, Deirdre M.

    2015-01-01

    Metabolomics, the latest “omic” technology, is defined as the comprehensive study of all low molecular weight biochemicals, “metabolites” present in an organism. As a systems biology approach, metabolomics has huge potential to progress our understanding of perinatal asphyxia and neonatal hypoxic-ischaemic encephalopathy, by uniquely detecting rapid biochemical pathway alterations in response to the hypoxic environment. The study of metabolomic biomarkers in the immediate neonatal period is not a trivial task and requires a number of specific considerations, unique to this disease and population. Recruiting a clearly defined cohort requires standardised multicentre recruitment with broad inclusion criteria and the participation of a range of multidisciplinary staff. Minimally invasive biospecimen collection is a priority for biomarker discovery. Umbilical cord blood presents an ideal medium as large volumes can be easily extracted and stored and the sample is not confounded by postnatal disease progression. Pristine biobanking and phenotyping are essential to ensure the validity of metabolomic findings. This paper provides an overview of the current state of the art in the field of metabolomics in perinatal asphyxia and neonatal hypoxic-ischaemic encephalopathy. We detail the considerations required to ensure high quality sampling and analysis, to support scientific progression in this important field. PMID:25802843

  12. The effect of biological and chemical factors on the uptake and toxicity of cadmium in the duckweed Lemna trisulca L

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huebert, D.B.

    1992-01-01

    The duckweed Lemna trisulca L. was grown in axenic cultures in a filter-sterilized medium. A portion of the medium was replaced regularly during experiments. The amount replaced doubled every two days. metal concentrations in the medium wee measured on the last day of experiments. The only organic compound added was FeEDTA at a concentration of 9 [mu]M. The chelating capacity of the medium was therefore minimal, defined and controlled. The nutrient medium and environmental conditions supported a doubling time of 1.6 to 2.4 days over a 14 day culture period. Under the above conditions, the EC50 (concentration at which amore » 50% effect is observed) for Cd and 0.99 [mu]M based on multiplication rate and 0.56 [mu]M based on final yield. The NOEC (no observable effect concentration) for Cd was between 120 and 150 [mu]g Cd/g dry wt. based on internal Cd, and 0.08 [mu]M based on external Cd. Internal Cd may be a superior estimate of toxicity because it avoids the problems associated with metal speciation in the external medium and allows for a comparison with field data. Lemna trisulca responded within 2 days to the addition of 0.64 [mu]M Cd. No tolerance to Cd was induced even after 6 weeks of exposure. The calculated response of L. trisulca to Cd may have been influenced by the multiplication rate of control cultures, which varied from 1.6 to 2.4 days. Calcium had no effect on Cd uptake or toxicity. Zinc antagonized Cd toxicity but had a variable effect on Cd uptake depending on its concentration. Zinc was about fifteen times less toxic than Cd. The uptake and toxicity of Cd and Zn were almost completely prevented when the level of available EDTA was in excess of the CD or Zn concentration. These data indicate that biological and chemical factors can profoundly influence the effect of toxicants on living organisms. These factors must be considered to ensure that toxicity studies are not confounded by effects extraneous to the actual effect of the toxicant.« less

  13. Isolation, Cloning and Expression of the Genes for Microbial Polyurethane Degradation

    DTIC Science & Technology

    1991-02-20

    Aspergillus niger --fungi ATCC 12668 Trichoderma sp.--fungi The minimal salts medium is as follows: 72 Minimal (NH4) 2s O 4 1.000 gm/L KH2PO4 5.000 gm/L MGSO 4...culture ATCC 35698 Arthobacter globiformis--bacteria ATCC 11172 Pseudomonas putida--bacteria ATCC 10196 Aspergillus oryzae--fungi ATCC 9642

  14. Cloning and characterization of the glutamate dehydrogenase gene in Streptococcus bovis.

    PubMed

    Ando, Tasuke; Sugawara, Yoko; Nishio, Ryohei; Murakami, Miho; Isogai, Emiko; Yoneyama, Hiroshi

    2017-07-01

    Streptococcus bovis, an etiologic agent of rumen acidosis in cattle, is a rumen bacterium that can grow in a chemically defined medium containing ammonia as a sole source of nitrogen. To understand its ability to assimilate inorganic ammonia, we focused on the function of glutamate dehydrogenase. In order to identify the gene encoding this enzyme, we first amplified an internal region of the gene by using degenerate primers corresponding to hexameric family I and NAD(P) + binding motifs. Subsequently, inverse PCR was used to identify the whole gene, comprising an open reading frame of 1350 bp that encodes 449 amino acid residues that appear to have the substrate binding site of glutamate dehydrogenase observed in other organisms. Upon introduction of a recombinant plasmid harboring the gene into an Escherichia coli glutamate auxotroph lacking glutamate dehydrogenase and glutamate synthase, the transformants gained the ability to grow on minimal medium without glutamate supplementation. When cell extracts of the transformant were resolved by blue native polyacrylamide gel electrophoresis followed by activity staining, a single protein band appeared that corresponded to the size of S. bovis glutamate dehydrogenase. Based on these results, we concluded that the gene obtained encodes glutamate dehydrogenase in S. bovis. © 2016 Japanese Society of Animal Science.

  15. Bioengineering pediatric scaffold-free auricular cartilaginous constructs.

    PubMed

    Akbari, Pedram; Waldman, Stephen D; Cushing, Sharon L; Papsin, Blake C; Propst, Evan J; Weber, Joanna F; Yeger, Herman; Farhat, Walid A

    2017-05-01

    The use of exogenous materials as scaffolds in cartilage tissue engineering has limited the clinical application of resultant constructs due to the risk of postoperative complications. In an effort to minimize such complications, we aim to generate human, scaffold-free auricular cartilaginous constructs. Laboratory study using pediatric auricular cartilage. Remnant, normal pediatric auricular cartilage samples that would have otherwise been discarded were collected and digested to free cells. Harvested cells were cultured and expanded in vitro for two passages and plated as micromass cultures. The culture medium was replaced with a chemically defined chondrogenic medium, and cellular monolayers surrounding micromass cultures were continuously scraped off. Constructs were allowed to mature for a period of 8 weeks. Micromass constructs showed mechanical stability and structurally resembled native auricular tissue, with a perichondrium-like layer of cells surrounding the inner cartilaginous zone. Constructs accumulated equivalent sulphated glycosaminoglycan and 50% of collagen content compared to native auricular cartilage by mass, while displaying 156% more cellularity. High-density micromass cultures of pediatric auricular chondrocytes can generate stable cartilaginous constructs following prolonged chondrogenic inductions in vitro. This technique is an essential step toward the development of three-dimensional constructs to recreate clinically applicable auricular cartilaginous constructs. NA. Laryngoscope, 127:E153-E158, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  16. Nutritional Control of Chronological Aging and Heterochromatin in Saccharomyces cerevisiae.

    PubMed

    McCleary, David F; Rine, Jasper

    2017-03-01

    Calorie restriction extends life span in organisms as diverse as yeast and mammals through incompletely understood mechanisms.The role of NAD + -dependent deacetylases known as Sirtuins in this process, particularly in the yeast Saccharomyces cerevisiae , is controversial. We measured chronological life span of wild-type and sir2 Δ strains over a higher glucose range than typically used for studying yeast calorie restriction. sir2 Δ extended life span in high glucose complete minimal medium and had little effect in low glucose medium, revealing a partial role for Sir2 in the calorie-restriction response under these conditions. Experiments performed on cells grown in rich medium with a newly developed genetic strategy revealed that sir2 Δ shortened life span in low glucose while having little effect in high glucose, again revealing a partial role for Sir2 In complete minimal media, Sir2 shortened life span as glucose levels increased; whereas in rich media, Sir2 extended life span as glucose levels decreased. Using a genetic strategy to measure the strength of gene silencing at HML , we determined increasing glucose stabilized Sir2-based silencing during growth on complete minimal media. Conversely, increasing glucose destabilized Sir-based silencing during growth on rich media, specifically during late cell divisions. In rich medium, silencing was far less stable in high glucose than in low glucose during stationary phase. Therefore, Sir2 was involved in a response to nutrient cues including glucose that regulates chronological aging, possibly through Sir2-dependent modification of chromatin or deacetylation of a nonhistone protein. Copyright © 2017 by the Genetics Society of America.

  17. Enterobactin-mediated iron transport in Pseudomonas aeruginosa.

    PubMed Central

    Poole, K; Young, L; Neshat, S

    1990-01-01

    A pyoverdine-deficient strain of Pseudomonas aeruginosa was unable to grow in an iron-deficient minimal medium in the presence of the nonmetabolizable iron chelator ethylene diamine-di(omega-hydroxyphenol acetic acid) (EDDHA), although addition of enterobactin to EDDHA-containing minimal media did restore growth of the pyoverdine-deficient P. aeruginosa. Consistent with the apparent ability of enterobactin to provide iron to P. aeruginosa, enterobactin-dependent 55Fe3+ uptake was observed in cells of P. aeruginosa previously grown in an iron-deficient medium containing enterobactin (or enterobactin-containing Escherichia coli culture supernatant). This uptake was energy dependent, was observable at low concentrations (60 nM) of FeCl3, and was absent in cells cultured without enterobactin. A novel protein with a molecular weight of approximately 80,000 was identified in the outer membranes of cells grown in iron-deficient minimal medium containing enterobactin, concomitant with the induction of enterobactin-dependent iron uptake. A Tn501 insertion mutant lacking this protein was isolated and shown to be deficient in enterobactin-mediated iron transport at 60 nM FeCl3, although it still exhibited enterobactin-dependent growth in iron-deficient medium containing EDDHA. It was subsequently observed that the mutant was, however, capable of enterobactin-mediated iron transport at much higher concentrations (600 nM) of FeCl3. Indeed, enterobactin-dependent iron uptake at this concentration of iron was observed in both the mutant and parent strains irrespective of whether they had been cultured in the presence of enterobactin.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:2174865

  18. Saccharomyces cerevisiae oxidative response evaluation by cyclic voltammetry and gas chromatography-mass spectrometry.

    PubMed

    Castro, Cristiana C; Gunning, Caitriona; Oliveira, Carla M; Couto, José A; Teixeira, José A; Martins, Rui C; Ferreira, António C Silva

    2012-07-25

    This study is focused on the evaluation of the impact of Saccharomyces cerevisiae metabolism in the profile of compounds with antioxidant capacity in a synthetic wine during fermentation. A bioanalytical pipeline, which allows for biological systems fingerprinting and sample classification by combining electrochemical features with biochemical background, is proposed. To achieve this objective, alcoholic fermentations of a minimal medium supplemented with phenolic acids were evaluated daily during 11 days, for electrochemical profile, phenolic acids, and the volatile fermentation fraction, using cyclic voltametry, high-performance liquid chromatography-diode array detection, and headspace/solid-phase microextraction/gas chromatography-mass spectrometry (target and nontarget approaches), respectively. It was found that acetic acid, 2-phenylethanol, and isoamyl acetate are compounds with a significative contribution for samples metabolic variability, and the electrochemical features demonstrated redox-potential changes throughout the alcoholic fermentations, showing at the end a similar pattern to normal wines. Moreover, S. cerevisiae had the capacity of producing chlorogenic acid in the supplemented medium fermentation from simple precursors present in the minimal medium.

  19. CBI: Systems or Medium?

    ERIC Educational Resources Information Center

    Higginbotham-Wheat, Nancy L.

    This paper addresses one area of conflict in decisionmaking in computer-based instruction (CBI) research: the relationship between the researcher's definition of CBI either as a medium or as an integrated system and the design of meaningful research questions. (A medium is defined here as a device for the delivery of instruction, while an…

  20. Degradation of Coal by the Fungi Polyporus versicolor and Poria monticola

    PubMed Central

    Cohen, Martin S.; Gabriele, Peter D.

    1982-01-01

    We report that two species of basidiomycete fungi (Polyporus versicolor and Poria monticola) grow in minimal liquid or solid medium when supplemented with crushed lignite coal. The fungi also grow directly on crushed lignite coal. The growth of both fungi was observed qualitatively as the production and extension of hyphae. No fungal growth occurred in minimal agar medium without coal. The fungi degraded solid lignite coal to a black liquid product which never appeared in cultures unless fungi and coal were present together. Apparently, lignite coal can serve as the principal substrate for the growth of the fungi. Infrared analyses of the liquid products of lignite degradation showed both similarities to and differences from the original lignite. Images PMID:16346060

  1. Parallel Optical Random Access Memory (PORAM)

    NASA Technical Reports Server (NTRS)

    Alphonse, G. A.

    1989-01-01

    It is shown that the need to minimize component count, power and size, and to maximize packing density require a parallel optical random access memory to be designed in a two-level hierarchy: a modular level and an interconnect level. Three module designs are proposed, in the order of research and development requirements. The first uses state-of-the-art components, including individually addressed laser diode arrays, acousto-optic (AO) deflectors and magneto-optic (MO) storage medium, aimed at moderate size, moderate power, and high packing density. The next design level uses an electron-trapping (ET) medium to reduce optical power requirements. The third design uses a beam-steering grating surface emitter (GSE) array to reduce size further and minimize the number of components.

  2. Quantification of biofilm structures by the novel computer program COMSTAT.

    PubMed

    Heydorn, A; Nielsen, A T; Hentzer, M; Sternberg, C; Givskov, M; Ersbøll, B K; Molin, S

    2000-10-01

    The structural organization of four microbial communities was analysed by a novel computer program, COMSTAT, which comprises ten features for quantifying three-dimensional biofilm image stacks. Monospecies biofilms of each of the four bacteria, Pseudomonas: putida, P. aureofaciens, P. fluorescens and P. aeruginosa, tagged with the green fluorescent protein (GFP) were grown in flow chambers with a defined minimal medium as substrate. Analysis by the COMSTAT program of four variables describing biofilm structure - mean thickness, roughness, substratum coverage and surface to volume ratio - showed that the four Pseudomonas: strains represent different modes of biofilm growth. P. putida had a unique developmental pattern starting with single cells on the substratum growing into micro-colonies, which were eventually succeeded by long filaments and elongated cell clusters. P. aeruginosa colonized the entire substratum, and formed flat, uniform biofilms. P. aureofaciens resembled P. aeruginosa, but had a stronger tendency to form micro-colonies. Finally, the biofilm structures of P. fluorescens had a phenotype intermediate between those of P. putida and P. aureofaciens. Analysis of biofilms of P. aureofaciens growing on 0.03 mM, 0.1 mM or 0.5 mM citrate minimal media showed that mean biofilm thickness increased with increasing citrate concentration. Moreover, biofilm roughness increased with lower citrate concentrations, whereas surface to volume ratio increased with higher citrate concentrations.

  3. A rapid and versatile method for the isolation, purification and cryogenic storage of Schwann cells from adult rodent nerves

    PubMed Central

    Andersen, Natalia D.; Srinivas, Shruthi; Piñero, Gonzalo; Monje, Paula V.

    2016-01-01

    We herein developed a protocol for the rapid procurement of adult nerve-derived Schwann cells (SCs) that was optimized to implement an immediate enzymatic dissociation of fresh nerve tissue while maintaining high cell viability, improving yields and minimizing fibroblast and myelin contamination. This protocol introduces: (1) an efficient method for enzymatic cell release immediately after removal of the epineurium and extensive teasing of the nerve fibers; (2) an adaptable drop-plating method for selective cell attachment, removal of myelin debris, and expansion of the initial SC population in chemically defined medium; (3) a magnetic-activated cell sorting purification protocol for rapid and effective fibroblast elimination; and (4) an optional step of cryopreservation for the storage of the excess of cells. Highly proliferative SC cultures devoid of myelin and fibroblast growth were obtained within three days of nerve processing. Characterization of the initial, expanded, and cryopreserved cell products confirmed maintenance of SC identity, viability and growth rates throughout the process. Most importantly, SCs retained their sensitivity to mitogens and potential for differentiation even after cryopreservation. To conclude, this easy-to-implement and clinically relevant protocol allows for the preparation of expandable homogeneous SC cultures while minimizing time, manipulation of the cells, and exposure to culture variables. PMID:27549422

  4. High energy XeBr electric discharge laser

    DOEpatents

    Sze, Robert C.; Scott, Peter B.

    1981-01-01

    A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

  5. High energy XeBr electric discharge laser

    DOEpatents

    Sze, R.C.; Scott, P.B.

    A high energy XeBr laser for producing coherent radiation at 282 nm is disclosed. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr, is used as the halogen donor which undergoes harpooning reactions with Xe/sub M/ to form XeBr.

  6. Growing media [Chapter 5

    Treesearch

    Douglass F. Jacobs; Thomas D. Landis; Tara Luna

    2009-01-01

    Selecting the proper growing medium is one of the most important considerations in nursery plant production. A growing medium can be defined as a substance through which roots grow and extract water and nutrients. In native plant nurseries, a growing medium can consist of native soil but is more commonly an "artificial soil" composed of materials such as peat...

  7. Liposome encapsulated soy lecithin and cholesterol can efficiently replace chicken egg yolk in human semen cryopreservation medium.

    PubMed

    Mutalik, Srinivas; Salian, Sujith Raj; Avadhani, Kiran; Menon, Jyothsna; Joshi, Haritima; Hegde, Aswathi Raju; Kumar, Pratap; Kalthur, Guruprasad; Adiga, Satish Kumar

    2014-06-01

    Cryopreservation of spermatozoa plays a significant role in reproductive medicine and fertility preservation. Chicken egg yolk is used as an extender in cryopreservation of human spermatozoa using glycerol egg yolk citrate (GEYC) buffered medium. Even though 50% survival of spermatozoa is generally achieved with this method, the risk of high levels of endotoxins and transmission pathogens from chicken egg yolk is a matter of concern. In the present study we attempted to establish a chemically defined cryopreservation medium which can replace the chicken egg yolk without affecting sperm survival. Ejaculates from 28 men were cryopreserved with GEYC based freezing medium or liposome encapsulated soy lecithin-cholesterol based freezing medium (LFM). The semen samples were subjected to rapid thawing after 14 days of storage in liquid nitrogen. Post-thaw analysis indicated significantly higher post-thaw motility and sperm survival in spermatozoa cryopreserved with LFM compared to conventional GEYC freezing medium. The soy lecithin and cholesterol at the ratio of 80:20 with sucrose showed the highest percentage of post-thaw motility and survival compared to the other compositions. In conclusion, chemically defined cryopreservation medium with liposome encapsulated soy lecithin and cholesterol can effectively replace the chicken egg yolk from human semen cryopreservation medium without compromising post-thaw outcome.

  8. A critical synopsis: Continuous growth of proximal tubular kidney epithelial cells in hormone-supplemented serum-free medium

    NASA Technical Reports Server (NTRS)

    Chuman, L. M.; FINE; COHEN; Saier, M. H.

    1985-01-01

    The kidney forms urine and reabsorbs electrolytes and water. Kidney cell lines and hormone supplemented serum free medium were used for growth. The hormones were insulin, transferrin, vasopressin, cholesterol, prostaglandins, hydrocortisone, and triidothyronine. Epithelial cell lines are polar and form hemicysts. The Madin-Darby canine kidney(MDCK) cell line used is distal tubulelike. LLC-PK sub 1 cells are derived from pig kidneys and have the properties of different kidney segments. The LLC-PK sub 1 cells with proximal tubule properties were maintained in hormone-supplemented serum free medium. Seven factors (the aforementioned homrones and selenium) were needed for growth. Hormone-defined medium supported LLC-PK sub 1 cell growth, allowed transport (as seen by hemicyst formation), and influenced cell morphology. Vasopressin (used for growth and morphology) could be partially replaced by isobutylmethylxanthine or dibutyryl cAMP. The defined medium was used to isolate rabbit proximal tubule kidney epithelial cells free of fibroblasts.

  9. Margins of safety provided by COSHH Essentials and the ILO Chemical Control Toolkit.

    PubMed

    Jones, Rachael M; Nicas, Mark

    2006-03-01

    COSHH Essentials, developed by the UK Health and Safety Executive, and the Chemical Control Toolkit (Toolkit) proposed by the International Labor Organization, are 'control banding' approaches to workplace risk management intended for use by proprietors of small and medium-sized businesses. Both systems group chemical substances into hazard bands based on toxicological endpoint and potency. COSSH Essentials uses the European Union's Risk-phrases (R-phrases), whereas the Toolkit uses R-phrases and the Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. Each hazard band is associated with a range of airborne concentrations, termed exposure bands, which are to be attained by the implementation of recommended control technologies. Here we analyze the margin of safety afforded by the systems and, for each hazard band, define the minimal margin as the ratio of the minimum airborne concentration that produced the toxicological endpoint of interest in experimental animals to the maximum concentration in workplace air permitted by the exposure band. We found that the minimal margins were always <100, with some ranging to <1, and inversely related to molecular weight. The Toolkit-GHS system generally produced margins equal to or larger than COSHH Essentials, suggesting that the Toolkit-GHS system is more protective of worker health. Although, these systems predict exposures comparable with current occupational exposure limits, we argue that the minimal margins are better indicators of health protection. Further, given the small margins observed, we feel it is important that revisions of these systems provide the exposure bands to users, so as to permit evaluation of control technology capture efficiency.

  10. Angiostrongylus cantonensis (Nematode: Metastrongiloidea): in vitro cultivation of infective third-stage larvae to fourth-stage larvae.

    PubMed

    Lin, Rong-Jyh; He, Jie-Wen; Chung, Li-Yu; Lee, June-Der; Wang, Jiun-Jye; Yen, Chuan-Min

    2013-01-01

    The present study to attempt to cultivate Angiostrongylus cantonensis from third-stage larvae (AcL3) to fourth-stage larvae (AcL4) in vitro in defined complete culture medium that contained with Minimum Essential Medium Eagle (MEM), supplemented amino acid (AA), amine (AM), fatty acid (FA), carbohydrate (CA) and 20% fetal calf serum (FCS) was successful. When AcL3 were cultured in the defined complete culture medium at 37°C in a 5% CO2 atmosphere, the larvae began to develop to AcL4 after 30 days of cultivation, and were enclosed within the sheaths of the third molts of the life cycle. Under these conditions, the larvae developed uniformly and reached to the fourth-stage 36 days. The morphology of AcL3 develop to AcL4 were recording and analyzing. Then comparison of A. cantonensis larval morphology and development between in vitro cultivation in defined complete culture medium and in vivo cultivation in infective BALB/c mice. The larvae that had been cultivated in vitro were smaller than AcL4 of infective BALB/c mice. However the AcL3 that were cultured using defined incomplete culture medium (MEM plus 20% FCS with AA+AM, FA, CA, AA+AM+FA, FA+CA, CA+AA+AM or not) did not adequately survive and develop. Accordingly, the inference is made that only the defined complete medium enable AcL3 develop to AcL4 in vitro. Some nematodes have been successfully cultured into mature worms but only a few researches have been made to cultivate A. cantonensis in vitro. The present study is the first to have succeeded in developing AcL3 to AcL4 by in vitro cultivation. Finally, the results of in vitro cultivation studies herein contribute to improving media for the effective development and growth of A. cantonensis. The gap in the A. cantonensis life cycle when the larvae are cultivated in vitro from third-stage larvae to fourth-stage larvae can thus be solved.

  11. The New Field Quantities and the Poynting Theorem in Material Medium with Magnetic Monopoles

    NASA Astrophysics Data System (ADS)

    Zor, Ömer

    2016-12-01

    The duality transformation was used to define the polarization mechanisms that arise from magnetic monopoles. Then, a dimensional analysis was conducted to describe the displacement and magnetic intensity vectors (constitutive equations) in SI units. Finally, symmetric Maxwell equations in a material medium with new field quantities were introduced. Hence, the Lorentz force and the Poynting theorem were defined with these new field quantities, and many possible definitions of them were constructed.

  12. Directed Biosynthesis of Oriented Crystalline Cellulose for Advanced Composite Fibers

    DTIC Science & Technology

    2012-05-03

    8 growth rate Table 2. An optimized minimal salts high conductivity growth medium (named 9 Son-Matsuoka- Fructose , SMF) based on the optimized...basis for a high -conductivity medium for Acetobacter that also contained corn steep liquor. List of Figures Figure 1. Scanning electron micrographs of...bacterial cellulose production include corn steep liquor (Matsuoka et al., 1996) apples, beer wort (Brown, 1886; Herrmann, 1928), corn syrup , kale (black

  13. Chemically Defined and Xeno-Free Cryopreservation of Human Adipose-Derived Stem Cells

    PubMed Central

    López, Melany; Bollag, Roni J.; Yu, Jack C.; Isales, Carlos M.; Eroglu, Ali

    2016-01-01

    The stromal compartment of adipose tissue harbors multipotent cells known as adipose-derived stem cells (ASCs). These cells can differentiate into various lineages including osteogenic, chrondrogenic, adipogenic, and neurogenic; this cellular fraction may be easily obtained in large quantities through a clinically safe liposuction procedure. Therefore, ASCs offer exceptional opportunities for tissue engineering and regenerative medicine. However, current practices involving ASCs typically use fetal bovine serum (FBS)-based cryopreservation solutions that are associated with risks of immunological reactions and of transmitting infectious diseases and prions. To realize clinical applications of ASCs, serum- and xeno-free defined cryopreservation methods are needed. To this end, an animal product-free chemically defined cryopreservation medium was formulated by adding two antioxidants (reduced glutathione and ascorbic acid 2-phosphate), two polymers (PVA and ficoll), two permeating cryoprotectants (ethylene glycol and dimethylsulfoxide), a disaccharide (trehalose), and a calcium chelator (EGTA) to HEPES-buffered DMEM/F12. To limit the number of experimental groups, the concentration of trehalose, both polymers, and EGTA was fixed while the presence of the permeating CPAs and antioxidants was varied. ASCs suspended either in different versions of the defined medium or in the conventional undefined cryopreservation medium (10% dimethylsulfoxide+10% DMEM/F12+80% serum) were cooled to -70°C at 1°C/min before being plunged into liquid nitrogen. Samples were thawed either in air or in a water bath at 37°C. The presence of antioxidants along with 3.5% concentration of each penetrating cryoprotectant improved the freezing outcome to the level of the undefined cryopreservation medium, but the plating efficiency was still lower than that of unfrozen controls. Subsequently, increasing the concentration of both permeating cryoprotectants to 5% further improved the plating efficiency to the level of unfrozen controls. Moreover, ASCs cryopreserved in this defined medium retained their multipotency and chromosomal normality. These results are of significance for tissue engineering and clinical applications of stem cells. PMID:27010403

  14. Iron in Neisseria meningitidis: minimum requirements, effects of limitation, and characteristics of uptake.

    PubMed Central

    Archibald, F S; DeVoe, I W

    1978-01-01

    A simple defined medium (neisseria defined medium) was devised that does not require iron extraction to produce iron-limited growth of Neisseria meningitidis (SDIC). Comparison of this medium to Mueller-Hinton broth and agar showed nearly identical growth rates and yields. The defined medium was used in batch cultures to determine the disappearance of iron from the medium and its uptake by cells. To avoid a number of problems inherent in batch culture, continuous culture, in which iron and dissolved oxygen were varied independently, was used. Most of the cellular iron was found to be nonheme and associated with the particulate fraction in sonically disrupted cells. Nonheme and catalase-heme iron were reduced by iron starvation far more than cytochromes b and c and N,N,N',N'-tetramethylphenylenediamine-oxidase. The respiration rate and efficiency also decreased under iron limitation, whereas generation times increased. The iron-starved meningococcus took up iron by an energy-independent system operating in the first minute after an iron pulse and a slower energy-dependent system inhibited by respiratory poisons and an uncoupler. The energy-dependent system showed saturation kinetics and was stimulated nearly fourfold by iron privation. In addition, to determine the availability to the meningococcus of the iron in selected compounds, a sensitive assay was devised in which an iron-limited continuous culture was pulsed with the iron-containing compound. PMID:101516

  15. Hepatotoxin N-nitrosomorpholine-induced carcinogenesis in rat liver: ex vivo exploration of preneoplastic and neoplastic hepatocytes.

    PubMed

    Jeong, Jin Sook; Lee, Sang Hyeung; Jung, Kap Joong; Choi, Yong C; Park, Woong Yang; Kim, In Hoo; Kim, Sang Soon

    2003-02-01

    N-nitrosomorpholine (NNM) is a hepatotoxic and hepatocarcinogenic agent. This agent was administered in the form of drinking water which contained 200 mg of NNM/liter. Its time-dependent intake profile showed four phases over 20 weeks, followed by a fifth phase where only water was supplied. Most frequently, hepatocellular carcinoma appeared between the end of phase IV and the beginning of phase V. At 5 weeks of NNM administration, foci of altered hepatocytes (FAH) containing 100-1000 hepatocytes could be isolated together with free hepatocytes by the collagenase perfusion method. When these foci were grown on the William's Medium E containing hormonally defined medium, they were able to survive approximately twice as long as normal hepatocytes At 10 weeks of NNM administration, few FAH were isolated together with free hepatocytes. The hepatocytes which had been placed under extended chemical stress showed increased heat tolerance (7 to 8 h) at 43 degrees C, while normal hepatocytes could survive 3 to 4 h. At the neoplastic phase spanning the end of the 20 weeks of the NNM administration and water phase, the rats bearing hepatocellular carcinoma entered the terminal stage, where observable tumor masses could be isolated from the tumor bearing liver and tested for ex vivo growth in tissue culture. After stabilization of the isolated primary hepatoma cells through 10 passages of propagation on William's Medium E or minimal Eagle's medium containing 10% FBS, their gene expression profile was analyzed by DNA microarray and compared with the profile of normal hepatocytes. The comparison revealed that upregulation involved ribosome-dependent protein synthesis, including 40S ribosomal proteins (S4, S7, S18, S20), 60S ribosomal proteins (L6, L21, L32, L37, P1), initiation factor 4A, and elongation factor 1alpha.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jassal, K; Sarkar, B; Ganesh, T

    Purpose: The study investigates the effect of fluence smoothing parameter on VMAT plans for ten head-neck cancer patients using Monaco5.00.04. Methods: VMAT plans were created using Monaco5.00.04 planning system for 10 head-neck patients. Four plans were generated for each patient using available smoothing parameters i.e. high, medium, low and off. The number of monitor units required to deliver 1 cGy was defined as a modulation degree; and was taken as a measure of plan complexity. Routinely used plan quality parameters Conformity index (CI) and Homogeneity index (HI) were used in the study. As a protocol our center, practices “medium” smoothingmore » for clinical implementation. Plans with medium smoothing were opted as reference plans due to the clinical acceptance and dosimetric verifications made on these plans. Plans were generated by varying the smoothing parameter and re-optimization was done. The PTV was evaluated for D98%, D95%, D50%, D1% and prescription isodose volume (PIV). For critical organs; spine and parotids the parameters recorded were D1cc and Dmean respectively. Results: The cohort had the median prescription as 6000 cGy in the range of 6600 cGy - 4500 cGy. The modulation degree was observed to increase up to 6% from reference to the most complex plan. High smoothing had about 11% increase in segments which marginally (0.5 to 1%) increased the homogeneity index while conformity index remains constant. For spine the maximum D1cc was observed in medium smoothing as 4639.8 cGy, this plan was clinically accepted and dosimetrically verified. Similarly for parotids, the Dmean was 2011.9 cGy and 1817.05 cGy. Conclusion: The sensitivity of plan quality in terms of smoothing options (high, medium, low and off) available in Monaco 5.00.04 was resulted in minimal difference in terms of target coverage, conformity index and homogeneity index. Similarly changing smoothing did not result in any enhanced advantage in sparing of critical organs.« less

  17. A protocol describing the use of a recombinant protein-based, animal product-free medium (APEL) for human embryonic stem cell differentiation as spin embryoid bodies.

    PubMed

    Ng, Elizabeth S; Davis, Richard; Stanley, Edouard G; Elefanty, Andrew G

    2008-01-01

    In order to promote the uniform and reproducible differentiation of human embryonic stem cells (HESCs) in response to exogenously added growth factors, we have developed a method (spin embryoid bodies (EBs)) that uses a recombinant protein-based, animal product-free medium in which HESCs are aggregated by centrifugation to form EBs. In this protocol we describe the formulation of this medium, denoted APEL (Albumin Polyvinylalcohol Essential Lipids), and its use in spin EB differentiation of HESCs. We also describe a more economical variant, BPEL (Bovine Serum Albumin (BSA) Polyvinylalchohol Essential Lipids), in which BSA replaces the recombinant human albumin. The integration of a medium that includes only defined and recombinant components with a defined number of cells to initiate EB formation results in a generally applicable, robust platform for growth factor-directed HESC differentiation.

  18. Formulation of a minimal nutritional medium for enhanced lipid productivity in Chlorella sp. and Botryococcus sp. using response surface methodology.

    PubMed

    Vishwakarma, Rashi; Dhar, Dolly Wattal; Pabbi, Sunil

    2018-03-01

    Chlorella sp. MCC 7 and Botryococcus sp. MCC 31 were investigated to enable large-scale biodiesel production from minimal constituents in the growth medium. Response surface methodology (RSM) was used to maximise the biomass productivity and lipid yield using only nitrogen (N), phosphorus (P) and potassium (K) as urea, single super phosphate and muriate of potash. The optimum values were 0.42 g/L nitrogen; 0.14 g/L phosphorus and 0.22 g/L potassium for Chlorella sp.; and 0.46 g/L; 0.14 g/L and 0.25 g/L for Botryococcus sp. Lipid yield of 42% for Chlorella sp. and 52% in Botryococcus sp. was observed. An enhancement in lipid yield by approximately 55% for Chlorella sp. and 73% for Botryococcus sp. was registered as compared to original nutrient medium. Fourier transform infrared (FTIR) analysis of extracted lipids revealed characteristic bands for triglycerides. This study provided utilisation of a practicable nutrient recipe in the form of N, P, K input for enhanced lipid yield from the selected microalgal strains.

  19. Enzymes of the Isoleucine-Valine Pathway in Acinetobacter

    PubMed Central

    Twarog, Robert

    1972-01-01

    Regulation of four of the enzymes required for isoleucine and valine biosynthesis in Acinetobacter was studied. A three- to fourfold derepression of acetohydroxyacid synthetase was routinely observed in two different wild-type strains when grown in minimal medium relative to cells grown in minimal medium supplemented with leucine, valine, and isoleucine. A similar degree of synthetase derepression was observed in appropriately grown isoleucine or leucine auxotrophs. No significant derepression of threonine deaminase or transaminase B occurred in either wild-type or mutant cells grown under a variety of conditions. Three amino acid analogues were tested with wild-type cells; except for a two- to threefold derepression of dihydroxyacid dehydrase when high concentrations of aminobutyric acid were added to the medium, essentially the same results were obtained. Experiments showed that threonine deaminase is subject to feedback inhibition by isoleucine and that valine reverses this inhibition. Cooperative effects in threonine deaminase were demonstrated with crude extracts. The data indicate that the synthesis of isoleucine and valine in Acinetobacter is regulated by repression control of acetohydroxyacid synthetase and feedback inhibition of threonine deaminase and acetohydroxyacid synthetase. PMID:4669215

  20. Analysis of Fatty Acid and Growth Profiles in Ten Shewanella spp. to Associate Phylogenetic Relationships

    DTIC Science & Technology

    2015-10-25

    in a defined medium composed of half-strength Marine Broth adjusted to pH 6, 7, or 8 in a 50 mM phosphate buffer, both growth characteristics and...work had broad phylogenetic diversity (Fig. 1) and were isolated from mostly marine environments. S. putrefaciens was the only strain that was not...the defined medium that supported growth of most of the strains tested was marine broth diluted to half strength with 50 mM phosphate buffer (½-MB

  1. Rapid Induction of Cerebral Organoids From Human Induced Pluripotent Stem Cells Using a Chemically Defined Hydrogel and Defined Cell Culture Medium.

    PubMed

    Lindborg, Beth A; Brekke, John H; Vegoe, Amanda L; Ulrich, Connor B; Haider, Kerri T; Subramaniam, Sandhya; Venhuizen, Scott L; Eide, Cindy R; Orchard, Paul J; Chen, Weili; Wang, Qi; Pelaez, Francisco; Scott, Carolyn M; Kokkoli, Efrosini; Keirstead, Susan A; Dutton, James R; Tolar, Jakub; O'Brien, Timothy D

    2016-07-01

    Tissue organoids are a promising technology that may accelerate development of the societal and NIH mandate for precision medicine. Here we describe a robust and simple method for generating cerebral organoids (cOrgs) from human pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. By using no additional neural induction components, cOrgs appeared on the hydrogel surface within 10-14 days, and under static culture conditions, they attained sizes up to 3 mm in greatest dimension by day 28. Histologically, the organoids showed neural rosette and neural tube-like structures and evidence of early corticogenesis. Immunostaining and quantitative reverse-transcription polymerase chain reaction demonstrated protein and gene expression representative of forebrain, midbrain, and hindbrain development. Physiologic studies showed responses to glutamate and depolarization in many cells, consistent with neural behavior. The method of cerebral organoid generation described here facilitates access to this technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. Tissue organoids are a promising technology with many potential applications, such as pharmaceutical screens and development of in vitro disease models, particularly for human polygenic conditions where animal models are insufficient. This work describes a robust and simple method for generating cerebral organoids from human induced pluripotent stem cells by using a chemically defined hydrogel material and chemically defined culture medium. This method, by virtue of its simplicity and use of defined materials, greatly facilitates access to cerebral organoid technology, enables scalable applications, and provides a potential pathway to translational applications where defined components are desirable. ©AlphaMed Press.

  2. Maintaining oncologic integrity with minimally invasive resection of pediatric embryonal tumors.

    PubMed

    Phelps, Hannah M; Ayers, Gregory D; Ndolo, Josephine M; Dietrich, Hannah L; Watson, Katherine D; Hilmes, Melissa A; Lovvorn, Harold N

    2018-05-08

    Embryonal tumors arise typically in infants and young children and are often massive at presentation. Operative resection is a cornerstone in the multimodal treatment of embryonal tumors but potentially disrupts therapeutic timelines. When used appropriately, minimally invasive surgery can minimize treatment delays. The oncologic integrity and safety attainable with minimally invasive resection of embryonal tumors, however, remains controversial. Query of the Vanderbilt Cancer Registry identified all children treated for intracavitary, embryonal tumors during a 15-year period. Tumors were assessed radiographically to measure volume (mL) and image-defined risk factors (neuroblastic tumors only) at time of diagnosis, and at preresection and postresection. Patient and tumor characteristics, perioperative details, and oncologic outcomes were compared between minimally invasive surgery and open resection of tumors of comparable size. A total of 202 patients were treated for 206 intracavitary embryonal tumors, of which 178 were resected either open (n = 152, 85%) or with minimally invasive surgery (n = 26, 15%). The 5-year, relapse-free, and overall survival were not significantly different after minimally invasive surgery or open resection of tumors having a volume less than 100 mL, corresponding to the largest resected with minimally invasive surgery (P = .249 and P = .124, respectively). No difference in margin status or lymph node sampling between the 2 operative approaches was detected (p = .333 and p = .070, respectively). Advantages associated with minimally invasive surgery were decreased blood loss (P < .001), decreased operating time (P = .002), and shorter hospital stay (P < .001). Characteristically, minimally invasive surgery was used for smaller volume and earlier stage neuroblastic tumors without image-defined risk factors. When selected appropriately, minimally invasive resection of pediatric embryonal tumors, particularly neuroblastic tumors, provides acceptable oncologic integrity. Large tumor volume, small patient size, and image-defined risk factors may limit the broader applicability of minimally invasive surgery. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. An Analytic Approach to Projectile Motion in a Linear Resisting Medium

    ERIC Educational Resources Information Center

    Stewart, Sean M.

    2006-01-01

    The time of flight, range and the angle which maximizes the range of a projectile in a linear resisting medium are expressed in analytic form in terms of the recently defined Lambert W function. From the closed-form solutions a number of results characteristic to the motion of the projectile in a linear resisting medium are analytically confirmed,…

  4. On multiple crack identification by ultrasonic scanning

    NASA Astrophysics Data System (ADS)

    Brigante, M.; Sumbatyan, M. A.

    2018-04-01

    The present work develops an approach which reduces operator equations arising in the engineering problems to the problem of minimizing the discrepancy functional. For this minimization, an algorithm of random global search is proposed, which is allied to some genetic algorithms. The efficiency of the method is demonstrated by the solving problem of simultaneous identification of several linear cracks forming an array in an elastic medium by using the circular Ultrasonic scanning.

  5. High energy KrCl electric discharge laser

    DOEpatents

    Sze, Robert C.; Scott, Peter B.

    1981-01-01

    A high energy KrCl laser for producing coherent radiation at 222 nm. Output energies on the order of 100 mJ per pulse are produced utilizing a discharge excitation source to minimize formation of molecular ions, thereby minimizing absorption of laser radiation by the active medium. Additionally, HCl is used as a halogen donor which undergoes a harpooning reaction with metastable Kr.sub.M * to form KrCl.

  6. High energy KrCl electric discharge laser

    DOEpatents

    Sze, R.C.; Scott, P.B.

    A high energy KrCl laser is presented for producing coherent radiation at 222 nm. Output energies on the order of 100 mJ per pulse are produced utilizing a discharge excitation source to minimize formation of molecular ions, thereby minimizing absorption of laser radiation by the active medium. Additionally, HCl is used as a halogen donor which undergoes a harpooning reaction with metastable Kr/sub M/ to form KrCl.

  7. Acridine orange staining reaction as an index of physiological activity in Escherichia coli

    NASA Technical Reports Server (NTRS)

    McFeters, G. A.; Singh, A.; Byun, S.; Callis, P. R.; Williams, S.

    1991-01-01

    The assumption that the acridine orange (AO) color reaction may be used as an index of physiological activity was investigated in laboratory grown Escherichia coli. Spectrofluorometric observations of purified nucleic acids, ribosomes and the microscopic color of bacteriophage-infected cells stained with AO confirmed the theory that single-stranded nucleic acids emit orange to red fluorescence while those that are double-stranded fluoresce green in vivo. Bacteria growing actively in a rich medium could be distinguished from cells in stationary phase by the AO reaction. Cells from log phase appeared red, whereas those in stationary phase were green. However, this differentiation was not seen when the bacteria were grown in a minimal medium or when a variation of the staining method was used. Also, shifting bacteria in stationary phase to starvation conditions rapidly changed their AO staining reaction. Boiling and exposure to lethal concentrations of azide and formalin resulted in stationary-phase cells that appeared red after staining but bacteria killed with chlorine remained green. These findings indicate that the AO staining reaction may be suggestive of physiological activity under defined conditions. However, variables in staining and fixation procedures as well as uncertainties associated with mixed bacterial populations in environmental samples may produce results that are not consistent with the classical interpretation of this reaction. The importance of validating the putative physiological implications of this staining reaction is stressed.

  8. Isolation of previously uncultured rumen bacteria by dilution to extinction using a new liquid culture medium.

    PubMed

    Kenters, Nikki; Henderson, Gemma; Jeyanathan, Jeyamalar; Kittelmann, Sandra; Janssen, Peter H

    2011-01-01

    A new anaerobic medium that mimics the salts composition of rumen fluid was used in conjunction with a dilution method of liquid culture to isolate fermentative bacteria from the rumen of a grass-fed sheep. The aim was to inoculate a large number of culture tubes each with a mean of <1 culturable cell, which should maximize the number of cultures that develop from a single bacterium. This minimizes the effort that has to be put into purifying the resultant cultures. Of 1000 tubes, 139 were growth positive. Of the 93 that were able to be subcultured, 54 (58%) appeared to be pure cultures. The phylogenetic placements of these 54 cultures, together with another 6 cultures obtained from a preliminary study, were determined. Using a criterion of <93% 16S rRNA gene sequence identity to a previously named bacterium as a proxy for defining a new genus, 27 (45%) of the 60 cultures belonged to 14 potentially novel genera. Many of these had 16S rRNA genes that shared >97% sequence identity to genes of uncultured bacteria detected in various gastrointestinal environments. This strategy has therefore allowed us to cultivate many novel rumen bacteria, opening the way to overcoming the lack of cultures of many of the groups detected using cultivation-independent methods. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Method for optical pumping of thin laser media at high average power

    DOEpatents

    Zapata, Luis E [Livermore, CA; Beach, Raymond J [Livermore, CA; Honea, Eric C [Sunol, CA; Payne, Stephen A [Castro Valley, CA

    2004-07-13

    A thin, planar laser material is bonded to a light guide of an index-matched material forming a composite disk. Diode array or other pump light is introduced into the composite disk through the edges of the disk. Pump light trapped within the composite disk depletes as it multi-passes the laser medium before reaching an opposing edge of the disk. The resulting compound optical structure efficiently delivers concentrated pump light and to a laser medium of minimum thickness. The external face of the laser medium is used for cooling. A high performance cooler attached to the external face of the laser medium rejects heat. Laser beam extraction is parallel to the heat flux to minimize optical distortions.

  10. Recombinant host cells and media for ethanol production

    DOEpatents

    Wood, Brent E; Ingram, Lonnie O; Yomano, Lorraine P; York, Sean W

    2014-02-18

    Disclosed are recombinant host cells suitable for degrading an oligosaccharide that have been optimized for growth and production of high yields of ethanol, and methods of making and using these cells. The invention further provides minimal media comprising urea-like compounds for economical production of ethanol by recombinant microorganisms. Recombinant host cells in accordance with the invention are modified by gene mutation to eliminate genes responsible for the production of unwanted products other than ethanol, thereby increasing the yield of ethanol produced from the oligosaccharides, relative to unmutated parent strains. The new and improved strains of recombinant bacteria are capable of superior ethanol productivity and yield when grown under conditions suitable for fermentation in minimal growth media containing inexpensive reagents. Systems optimized for ethanol production combine a selected optimized minimal medium with a recombinant host cell optimized for use in the selected medium. Preferred systems are suitable for efficient ethanol production by simultaneous saccharification and fermentation (SSF) using lignocellulose as an oligosaccharide source. The invention also provides novel isolated polynucleotide sequences, polypeptide sequences, vectors and antibodies.

  11. Preferential flow occurs in unsaturated conditions

    USGS Publications Warehouse

    Nimmo, John R.

    2012-01-01

    Because it commonly generates high-speed, high-volume flow with minimal exposure to solid earth materials, preferential flow in the unsaturated zone is a dominant influence in many problems of infiltration, recharge, contaminant transport, and ecohydrology. By definition, preferential flow occurs in a portion of a medium – that is, a preferred part, whether a pathway, pore, or macroscopic subvolume. There are many possible classification schemes, but usual consideration of preferential flow includes macropore or fracture flow, funneled flow determined by macroscale heterogeneities, and fingered flow determined by hydraulic instability rather than intrinsic heterogeneity. That preferential flow is spatially concentrated associates it with other characteristics that are typical, although not defining: it tends to be unusually fast, to transport high fluxes, and to occur with hydraulic disequilibrium within the medium. It also has a tendency to occur in association with large conduits and high water content, although these are less universal than is commonly assumed. Predictive unsaturated-zone flow models in common use employ several different criteria for when and where preferential flow occurs, almost always requiring a nearly saturated medium. A threshold to be exceeded may be specified in terms of the following (i) water content; (ii) matric potential, typically a value high enough to cause capillary filling in a macropore of minimum size; (iii) infiltration capacity or other indication of incipient surface ponding; or (iv) other conditions related to total filling of certain pores. Yet preferential flow does occur without meeting these criteria. My purpose in this commentary is to point out important exceptions and implications of ignoring them. Some of these pertain mainly to macropore flow, others to fingered or funneled flow, and others to combined or undifferentiated flow modes.

  12. Minimizing communication cost among distributed controllers in software defined networks

    NASA Astrophysics Data System (ADS)

    Arlimatti, Shivaleela; Elbreiki, Walid; Hassan, Suhaidi; Habbal, Adib; Elshaikh, Mohamed

    2016-08-01

    Software Defined Networking (SDN) is a new paradigm to increase the flexibility of today's network by promising for a programmable network. The fundamental idea behind this new architecture is to simplify network complexity by decoupling control plane and data plane of the network devices, and by making the control plane centralized. Recently controllers have distributed to solve the problem of single point of failure, and to increase scalability and flexibility during workload distribution. Even though, controllers are flexible and scalable to accommodate more number of network switches, yet the problem of intercommunication cost between distributed controllers is still challenging issue in the Software Defined Network environment. This paper, aims to fill the gap by proposing a new mechanism, which minimizes intercommunication cost with graph partitioning algorithm, an NP hard problem. The methodology proposed in this paper is, swapping of network elements between controller domains to minimize communication cost by calculating communication gain. The swapping of elements minimizes inter and intra communication cost among network domains. We validate our work with the OMNeT++ simulation environment tool. Simulation results show that the proposed mechanism minimizes the inter domain communication cost among controllers compared to traditional distributed controllers.

  13. Minimal measures on surfaces of higher genus

    NASA Astrophysics Data System (ADS)

    Wang, Fang

    We study the minimal measures for positive definite autonomous Lagrangian systems defined on the tangent bundles of compact surfaces with genus greater than one. We present some results on the structure of minimal measures on compact surfaces. Specifically, we give a finer description of the structure of minimal measures with rational rotation vectors for geodesic flows on compact surfaces.

  14. Biodegradation of isopropanol and acetone under denitrifying conditions by Thauera sp. TK001 for nitrate-mediated microbially enhanced oil recovery.

    PubMed

    Fida, Tekle Tafese; Gassara, Fatma; Voordouw, Gerrit

    2017-07-15

    Amendment of reservoir fluid with injected substrates can enhance the growth and activity of microbes. The present study used isopropyl alcohol (IPA) or acetone to enhance the indigenous anaerobic nitrate-reducing bacterium Thauera sp. TK001. The strain was able to grow on IPA or acetone and nitrate. To monitor effects of strain TK001 on oil recovery, sand-packed columns containing heavy oil were flooded with minimal medium at atmospheric or high (400psi) pressure. Bioreactors were then inoculated with 0.5 pore volume (PV) of minimal medium containing Thauera sp. TK001 with 25mM of acetone or 22.2mM of IPA with or without 80mM nitrate. Incubation without flow for two weeks and subsequent injection with minimal medium gave an additional 17.0±6.7% of residual oil in place (ROIP) from low-pressure bioreactors and an additional 18.3% of ROIP from the high-pressure bioreactors. These results indicate that acetone or IPA, which are commonly used organic solvents, are good substrates for nitrate-mediated microbial enhanced oil recovery (MEOR), comparable to glucose, acetate or molasses, tested previously. This technology may be used for coupling biodegradation of IPA and/or acetone in waste streams to MEOR where these waste streams are generated in close proximity to an oil field. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. SiGe epitaxial memory for neuromorphic computing with reproducible high performance based on engineered dislocations

    NASA Astrophysics Data System (ADS)

    Choi, Shinhyun; Tan, Scott H.; Li, Zefan; Kim, Yunjo; Choi, Chanyeol; Chen, Pai-Yu; Yeon, Hanwool; Yu, Shimeng; Kim, Jeehwan

    2018-01-01

    Although several types of architecture combining memory cells and transistors have been used to demonstrate artificial synaptic arrays, they usually present limited scalability and high power consumption. Transistor-free analog switching devices may overcome these limitations, yet the typical switching process they rely on—formation of filaments in an amorphous medium—is not easily controlled and hence hampers the spatial and temporal reproducibility of the performance. Here, we demonstrate analog resistive switching devices that possess desired characteristics for neuromorphic computing networks with minimal performance variations using a single-crystalline SiGe layer epitaxially grown on Si as a switching medium. Such epitaxial random access memories utilize threading dislocations in SiGe to confine metal filaments in a defined, one-dimensional channel. This confinement results in drastically enhanced switching uniformity and long retention/high endurance with a high analog on/off ratio. Simulations using the MNIST handwritten recognition data set prove that epitaxial random access memories can operate with an online learning accuracy of 95.1%.

  16. A chemically defined culture medium containing Rho kinase inhibitor Y-27632 for the fabrication of stratified squamous epithelial cell grafts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aslanova, Afag; Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, TWIns, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666; Takagi, Ryo

    With the development of a culture method for stratified squamous epithelial cells, tissue-engineered epithelial cell sheets have been successfully applied as clinical cell grafts. However, the implementation of these cell sheets without the use of any animal-derived materials is highly desirable. In this study, Rho-associated protein kinase inhibitor Y-27632 was used to develop a chemically defined culture medium for the fabrication of stratified epithelial cell grafts consisting of human epidermal and oral keratinocytes, and the proliferation activity, cell morphology, and gene expressions of the keratinocytes were analyzed. The results of a colorimetric assay indicated that Y-27632 significantly promoted the proliferationmore » of the keratinocytes in culture media both with and without fetal bovine serum (FBS), although there were no indications of Y-27632 efficacy on cell morphology and stratification of the keratinocytes in culture medium without any animal-derived materials. The results of quantitative RT-PCR revealed that gene expressions correlated with cell adhesion, cell–cell junction, proliferation markers, and stem/progenitor markers in cultured keratinocytes were not strongly affected by the addition of Y-27632 to the culture medium. Moreover, gene expressions of differentiation markers in stratified keratinocytes cultured in medium without FBS were nearly identical to those of keratinocytes co-cultured with 3T3 feeder cells. Interestingly, the expressions of differentiation markers in cultured stratified keratinocytes were suppressed by FBS, whereas they were reconstructed by either co-culture of a 3T3 feeder layer or addition of Y-27632 into the culture medium containing FBS. These findings indicate that Y-27632 is a useful supplement for the development of a chemically defined culture medium for fabrication of stratified epithelial cell grafts for clinical applications for the purpose of developing the culture medium with a lower risk of pathogen transmission that might arise from animal-derived materials. - Highlights: • Y-27632 promotes the proliferation of human keratinocytes. • Human keratinocytes with Y-27632 can stratify similarly to traditional method. • Y-27632 is useful for culture medium of human keratinocyte in clinical setting.« less

  17. Determination of lytic enzyme activities of indigenous Trichoderma isolates from Pakistan.

    PubMed

    Asad, Saeed Ahmad; Tabassum, Ayesha; Hameed, Abdul; Hassan, Fayyaz Ul; Afzal, Aftab; Khan, Sabaz Ali; Ahmed, Rafiq; Shahzad, Muhammad

    2015-01-01

    This study investigated lytic enzyme activities in three indigenous Trichoderma strains namely, Trichoderma asperellum, Trichoderma harzianum and Trichoderma sp. Native Trichoderma strains and a virulent strain of Rhizoctonia solani isolated from infected bean plants were also included in the study. Enzyme activities were determined by measuring sugar reduction by dinitrosalicylic acid (DNS) method using suitable substrates. The antagonists were cultured in minimal salt medium with the following modifications: medium A (1 g of glucose), medium B (0.5 g of glucose + 0.5 g of deactivated R. solani mycelia), medium C (1.0 g of deactivated respective antagonist mycelium) and medium D (1 g of deactivated R. solani mycelia). T asperellum showed presence of higher amounts of chitinases, β-1, 3-glucanases and xylanases in extracellular protein extracts from medium D as compared to medium A. While, the higher activities of glucosidases and endoglucanses were shown in medium D extracts by T. harzianum. β-glucosidase activities were lower compared with other enzymes; however, activities of the extracts of medium D were significantly different. T. asperellum exhibited maximum inhibition (97.7%). On the other hand, Trichoderma sp. did not show any effect on mycelia growth of R. solani on crude extract.

  18. Determination of lytic enzyme activities of indigenous Trichoderma isolates from Pakistan

    PubMed Central

    Asad, Saeed Ahmad; Tabassum, Ayesha; Hameed, Abdul; Hassan, Fayyaz ul; Afzal, Aftab; Khan, Sabaz Ali; Ahmed, Rafiq; Shahzad, Muhammad

    2015-01-01

    Abstract This study investigated lytic enzyme activities in three indigenous Trichoderma strains namely, Trichoderma asperellum, Trichoderma harzianum and Trichoderma sp. Native Trichoderma strains and a virulent strain of Rhizoctonia solani isolated from infected bean plants were also included in the study. Enzyme activities were determined by measuring sugar reduction by dinitrosalicylic acid (DNS) method using suitable substrates. The antagonists were cultured in minimal salt medium with the following modifications: medium A (1 g of glucose), medium B (0.5 g of glucose + 0.5 g of deactivated R. solani mycelia), medium C (1.0 g of deactivated respective antagonist mycelium) and medium D (1 g of deactivated R. solani mycelia). T asperellum showed presence of higher amounts of chitinases, β-1, 3-glucanases and xylanases in extracellular protein extracts from medium D as compared to medium A. While, the higher activities of glucosidases and endoglucanses were shown in medium D extracts by T. harzianum. β-glucosidase activities were lower compared with other enzymes; however, activities of the extracts of medium D were significantly different. T. asperellum exhibited maximum inhibition (97.7%). On the other hand, Trichoderma sp. did not show any effect on mycelia growth of R. solani on crude extract. PMID:26691463

  19. Biological and physicochemical characterization of a serum- and xeno-free chemically defined cryopreservation procedure for adult human progenitor cells.

    PubMed

    Zeisberger, Steffen M; Schulz, Julia C; Mairhofer, Mario; Ponsaerts, Peter; Wouters, Guy; Doerr, Daniel; Katsen-Globa, Alisa; Ehrbar, Martin; Hescheler, Jurgen; Hoerstrup, Simon P; Zisch, Andreas H; Kolbus, Andrea; Zimmermann, Heiko

    2011-01-01

    While therapeutic cell transplantations using progenitor cells are increasingly evolving towards phase I and II clinical trials and chemically defined cell culture is established, standardization in biobanking is still in the stage of infancy. In this study, the EU FP6-funded CRYSTAL (CRYo-banking of Stem cells for human Therapeutic AppLication) consortium aimed to validate novel Standard Operating Procedures (SOPs) to perform and validate xeno-free and chemically defined cryopreservation of human progenitor cells and to reduce the amount of the potentially toxic cryoprotectant additive (CPA) dimethyl sulfoxide (DMSO). To achieve this goal, three human adult progenitor and stem cell populations-umbilical cord blood (UCB)-derived erythroid cells (UCB-ECs), UCB-derived endothelial colony forming cells (UCB-ECFCs), and adipose tissue (AT)-derived mesenchymal stromal cells (AT-MSCs)-were cryopreserved in chemically defined medium supplemented with 10% or 5% DMSO. Cell recovery, cell repopulation, and functionality were evaluated postthaw in comparison to cryopreservation in standard fetal bovine serum (FBS)-containing freezing medium. Even with a reduction of the DMSO CPA to 5%, postthaw cell count and viability assays indicated no overall significant difference versus standard cryomedium. Additionally, to compare cellular morphology/membrane integrity and ice crystal formation during cryopreservation, multiphoton laser-scanning cryomicroscopy (cryo-MPLSM) and scanning electron microscopy (SEM) were used. Neither cryo-MPLSM nor SEM indicated differences in membrane integrity for the tested cell populations under various conditions. Moreover, no influence was observed on functional properties of the cells following cryopreservation in chemically defined freezing medium, except for UCB-ECs, which showed a significantly reduced differentiation capacity after cryopreservation in chemically defined medium supplemented with 5% DMSO. In summary, these results demonstrate the feasibility and robustness of standardized xeno-free cryopreservation of different human progenitor cells and encourage their use even more in the field of tissue-engineering and regenerative medicine.

  20. CD-ROM preparation: An overview and guide

    NASA Technical Reports Server (NTRS)

    Daniel, Ralph E.; Jeschke, Mark W.; Schroer, James A.

    1995-01-01

    A primer on the options and procedures involved in producing CD-ROM products in a small to medium sized business operation is presented in language that persons with a minimal technical background can easily understand. The capabilities, limitations, and standards of CD-ROM technology are surveyed. Emphasis is placed on CD-ROM production, especially upon design, data conversion to an electronic medium, data file preparation, the use of vendors, and the steps for in-house production of CD-ROM products.

  1. Vertical ascending electrophoresis of cells with a minimal stabilizing medium

    NASA Technical Reports Server (NTRS)

    Omenyi, S. N.; Snyder, R. S.

    1983-01-01

    Vertical fractionation of a mixture of fixed horse and human red blood cells layered over a stabilizing support medium was done to give a valid comparison with proposed space experiments. In particular, the effects of sample thickness and concentration on zone migration rate were investigated. Electrophoretic mobilities of horse and human cells calculated from zone migration rates were compatible with those obtained by microelectrophoresis. Complete cell separation was observed when low power and effective cooling were employed.

  2. Method for electrically producing dispersions of a nonconductive fluid in a conductive medium

    DOEpatents

    DePaoli, D.W.; Tsouris, C.; Feng, J.Q.

    1998-06-09

    A method is described for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway. 4 figs.

  3. Method for electrically producing dispersions of a nonconductive fluid in a conductive medium

    DOEpatents

    DePaoli, David W.; Tsouris, Constantinos; Feng, James Q.

    1998-01-01

    A method for use in electrically forming dispersions of a nonconducting fluid in a conductive medium that minimizes power consumption, gas generation, and sparking between the electrode of the nozzle and the conductive medium. The method utilizes a nozzle having a passageway, the wall of which serves as the nozzle electrode, for the transport of the nonconducting fluid into the conductive medium. A second passageway provides for the transport of a flowing low conductivity buffer fluid which results in a region of the low conductivity buffer fluid immediately adjacent the outlet from the first passageway to create the necessary protection from high current drain and sparking. An electrical potential difference applied between the nozzle electrode and an electrode in contact with the conductive medium causes formation of small droplets or bubbles of the nonconducting fluid within the conductive medium. A preferred embodiment has the first and second passageways arranged in a concentric configuration, with the outlet tip of the first passageway withdrawn into the second passageway.

  4. Localization of a small change in a multiple scattering environment without modeling of the actual medium.

    PubMed

    Rakotonarivo, S T; Walker, S C; Kuperman, W A; Roux, P

    2011-12-01

    A method to actively localize a small perturbation in a multiple scattering medium using a collection of remote acoustic sensors is presented. The approach requires only minimal modeling and no knowledge of the scatterer distribution and properties of the scattering medium and the perturbation. The medium is ensonified before and after a perturbation is introduced. The coherent difference between the measured signals then reveals all field components that have interacted with the perturbation. A simple single scatter filter (that ignores the presence of the medium scatterers) is matched to the earliest change of the coherent difference to localize the perturbation. Using a multi-source/receiver laboratory setup in air, the technique has been successfully tested with experimental data at frequencies varying from 30 to 60 kHz (wavelength ranging from 0.5 to 1 cm) for cm-scale scatterers in a scattering medium with a size two to five times bigger than its transport mean free path. © 2011 Acoustical Society of America

  5. Image analysis technique as a tool to identify morphological changes in Trametes versicolor pellets according to exopolysaccharide or laccase production.

    PubMed

    Tavares, Ana P M; Silva, Rui P; Amaral, António L; Ferreira, Eugénio C; Xavier, Ana M R B

    2014-02-01

    Image analysis technique was applied to identify morphological changes of pellets from white-rot fungus Trametes versicolor on agitated submerged cultures during the production of exopolysaccharide (EPS) or ligninolytic enzymes. Batch tests with four different experimental conditions were carried out. Two different culture media were used, namely yeast medium or Trametes defined medium and the addition of lignolytic inducers as xylidine or pulp and paper industrial effluent were evaluated. Laccase activity, EPS production, and final biomass contents were determined for batch assays and the pellets morphology was assessed by image analysis techniques. The obtained data allowed establishing the choice of the metabolic pathways according to the experimental conditions, either for laccase enzymatic production in the Trametes defined medium, or for EPS production in the rich Yeast Medium experiments. Furthermore, the image processing and analysis methodology allowed for a better comprehension of the physiological phenomena with respect to the corresponding pellets morphological stages.

  6. Astrocytes produce an insulin-like neurotrophic factor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kadle, R.; Suksang, C.; Fellows, R.E.

    1986-05-01

    They have previously reported that survival of dissociated neurons from fetal rat telencephalon plated at low density in serum-free, hormone-free defined medium is enhanced in the presence of insulin. In the absence of insulin a similar effect on neuronal survival is observed if cells are grown in medium conditioned by glial cells. The present study was carried out to characterize the insulin-like neurotrophic activity present in the glial conditioned medium (GLCM). Conditioned medium from confluent cultures of astrogial cells maintained in a serum free defined medium without insulin was collected every two or three days. A 5 to 30kDa fractionmore » of this medium was obtained by filtering it sequentially through YM30 and YM5 membrane filters. Binding of /sup 125/I-insulin to high density neuronal cultures was inhibited 43% by this fraction. Radioimmunoassay for insulin indicated that 1-2 ng of immuno-reactive insulin were present per ml of GLCM. Immunosequestration of the factor by insulin antibodies bound to protein A agarose gel resulted in loss of neurotrophic activity of the 5 to 30 kDa fraction. These results indicate that cultured astrocytes produce a factor immunologically and biochemically similar to insulin. This factor enhances the survival of neurons in culture and may be important for their normal development and differentiation.« less

  7. A Newly Defined and Xeno-Free Culture Medium Supports Every-Other-Day Medium Replacement in the Generation and Long-Term Cultivation of Human Pluripotent Stem Cells.

    PubMed

    Ahmadian Baghbaderani, Behnam; Tian, Xinghui; Scotty Cadet, Jean; Shah, Kevan; Walde, Amy; Tran, Huan; Kovarcik, Don Paul; Clarke, Diana; Fellner, Thomas

    2016-01-01

    Human pluripotent stem cells (hPSCs) present an unprecedented opportunity to advance human health by offering an alternative and renewable cell resource for cellular therapeutics and regenerative medicine. The present demand for high quality hPSCs for use in both research and clinical studies underscores the need to develop technologies that will simplify the cultivation process and control variability. Here we describe the development of a robust, defined and xeno-free hPSC medium that supports reliable propagation of hPSCs and generation of human induced pluripotent stem cells (hiPSCs) from multiple somatic cell types; long-term serial subculturing of hPSCs with every-other-day (EOD) medium replacement; and banking fully characterized hPSCs. The hPSCs cultured in this medium for over 40 passages are genetically stable, retain high expression levels of the pluripotency markers TRA-1-60, TRA-1-81, Oct-3/4 and SSEA-4, and readily differentiate into ectoderm, mesoderm and endoderm. Importantly, the medium plays an integral role in establishing a cGMP-compliant process for the manufacturing of hiPSCs that can be used for generation of clinically relevant cell types for cell replacement therapy applications.

  8. Minimal metabolic pathway structure is consistent with associated biomolecular interactions

    PubMed Central

    Bordbar, Aarash; Nagarajan, Harish; Lewis, Nathan E; Latif, Haythem; Ebrahim, Ali; Federowicz, Stephen; Schellenberger, Jan; Palsson, Bernhard O

    2014-01-01

    Pathways are a universal paradigm for functionally describing cellular processes. Even though advances in high-throughput data generation have transformed biology, the core of our biological understanding, and hence data interpretation, is still predicated on human-defined pathways. Here, we introduce an unbiased, pathway structure for genome-scale metabolic networks defined based on principles of parsimony that do not mimic canonical human-defined textbook pathways. Instead, these minimal pathways better describe multiple independent pathway-associated biomolecular interaction datasets suggesting a functional organization for metabolism based on parsimonious use of cellular components. We use the inherent predictive capability of these pathways to experimentally discover novel transcriptional regulatory interactions in Escherichia coli metabolism for three transcription factors, effectively doubling the known regulatory roles for Nac and MntR. This study suggests an underlying and fundamental principle in the evolutionary selection of pathway structures; namely, that pathways may be minimal, independent, and segregated. PMID:24987116

  9. A holistic evaluation of risks in coastal regions under changing climatic, environmental and socioeconomic conditions: the Theseus Decision Support System.

    NASA Astrophysics Data System (ADS)

    Losada, I. J.; Garcia Alonso, E.; Mendez, F. J.; Zanuttigh, B.; Nicholls, R. J.; Thompson, R.; Vanderlinden, J. P.; Fernandez, F.; Ondiviela, B.; Diaz-Simal, P.; Bagli, S.

    2012-04-01

    There is a general acceptance that global changes associated with natural hazards and socioeconomic processes are occurring at a faster pace than ever, with deep implications in terms of risk exposure and environmental impact. The capacity of coastal areas to adapt and react to these changes will be a key factor in the future preservation of life standards and represents a great challenge for politicians, scientists and professionals at any level. Within the large scope of Theseus Project (EU 7th Framework Program), one of the main objectives is to design a tool to help decision makers in defining optimal strategies to minimize risks within a certain city or coastal area in a three-fold sense: economic losses, human damages and environmental impacts. The resulting software, the Theseus-DSS, links the most relevant physical processes (waves, sea-levels, hard and soft structures, coastal erosion and inland flooding) with the potential impact zones (marine and inland), considering their functions (ecosystems) and uses (economic units), and the dependence of this functions and uses upon the prevailing physical conditions. The new software tries to fill a gap among the existing tools, based on the following pillars: • Seamless integration of disciplines: physics, engineering, ecology, social sciences and economy. • Intermediate spatial scales (1- 10 km) and medium-to- long time spans (1-10 years). • Decision-making based on a balance between deterministic models and expert, discussion-based assumptions. The user of the Theseus-DSS will be able either to check the consequences of predefined scenarios at a particular study site, or to create user-defined scenarios, run them and compare the results with other scenarios. The results are expressed, locally and at an aggregate level, in the three aforementioned dimensions: economic losses (€/year), mean annual expected live losses (persons/year) and impact on habitats (null, low, medium and high).

  10. Rate of deoxygenation modulates rheologic behavior of sickle red blood cells at a given mean corpuscular hemoglobin concentration.

    PubMed

    Kaul, D K; Liu, X D

    1999-01-01

    Although the mean corpuscular hemoglobin concentration (MCHC) plays a dominant role in the rheologic behavior of deoxygenated density-defined sickle red blood cells (SS RBCs), previous studies have not explored the relationship between the rate of deoxygenation and the bulk viscosity of SS RBCs at a given MCHC. In the present study, we have subjected density-defined SS classes (i.e., medium-density SS4 and dense SS5 discocytes) to varying deoxygenation rates. This approach has allowed us to minimize the effects of SS RBC heterogeneity and investigate the effect of deoxygenation rates at a given MCHC. The results show that the percentages of granular cells, classic sickle cells and holly leaf forms in deoxygenated samples are significantly influenced by the rate of deoxygenation and the MCHC of a given discocyte subpopulation. Increasing the deoxygenation rate using high K+ medium (pH 6.8), results in a greater percentage of granular cells in SS4 suspensions, accompanied by a pronounced increase in the bulk viscosity of these cells compared with gradually deoxygenated samples (mainly classic sickle cells and holly leaf forms). The effect of MCHC becomes apparent when SS5 dense cells are subjected to varying deoxygenation rates. At a given deoxygenation rate, SS5 dense discocytes show a greater increase in the percentage of granular cells than that observed for SS4 RBCs. Also, at a given deoxygenation rate, SS5 suspensions exhibit a higher viscosity than SS4 suspensions with fast deoxygenation resulting in maximal increase in viscosity. Although MCHC is the main determinant of SS RBC rheologic behavior, these studies demonstrate for the first time that at a given MCHC, the rate of deoxygenation (hence HbS polymerization rates) further modulates the rheologic behavior of SS RBCs. Thus, both MCHC and the deoxygenation rate may contribute to microcirculatory flow behavior of SS RBCs.

  11. The web-based information system for small and medium enterprises of Tomsk region

    NASA Astrophysics Data System (ADS)

    Senchenko, P. V.; Zhukovskiy, O. I.; Gritsenko, Yu B.; Senchenko, A. P.; Gritsenko, L. M.; Kovaleva, E. V.

    2017-01-01

    This paper presents the web enabled automated information data support system of small and medium-sized enterprises of Tomsk region. We define the purpose and application field of the system. In addition, we build a generic architecture and find system functions.

  12. Homogeneity requirements for minimizing self-focusing damage by strong electromagnetic waves

    NASA Technical Reports Server (NTRS)

    Jokipii, J. R.; Marburger, J.

    1973-01-01

    The Rytov approximation for wave propagation in random media is generalized to include the effects of self-focusing. Solutions are obtained which show how the intensity fluctuations, which are either initially present in the wave or which are induced by the random inhomogeneities in the media, grow catastrophically. These solutions may be used to obtain conditions on the homogeneity of the medium, or of the incident beam, for reduction or elimination of catastrophic self-focusing in the medium.

  13. Helix handedness of Leptospira interrogans as determined by scanning electron microscopy.

    PubMed Central

    Carleton, O; Charon, N W; Allender, P; O'Brien, S

    1979-01-01

    Representative serovars and strains of the seven genetic groups of Leptospira interrogans, and two previously studied serovars, were all found to form exclusively right-handed helices as determined by scanning electron microscopy. No change in handedness occurred in cells grown in a minimal medium (Tween-80 albumin) compared to cells grown in a rich medium (rabbit serum). The right-handedness of the organisms was related to the evolution, cell wall structure, and the mechanism of motility of L. interrogans. Images PMID:438122

  14. Biosynthesis of branched-chain amino acids is essential for effective symbioses between betarhizobia and Mimosa pudica.

    PubMed

    Chen, Wen-Ming; Prell, Jurgen; James, Euan K; Sheu, Der-Shyan; Sheu, Shih-Yi

    2012-07-01

    Burkholderia phymatum STM815 and Cupriavidus taiwanensis LMG19424 are betaproteobacterial strains that can effectively nodulate several species of the large legume genus Mimosa. A Tn5 mutant, derived from B. phymatum STM815 (KM60), and another derived from C. taiwanensis LMG19424 (KM184-55) induced Fix(-) nodules on Mimosa pudica. The Tn5-interrupted genes of the mutants showed strong homologies to ilvE, which encodes a branched-chain amino acid aminotransferase, and leuC, which encodes the large subunit of isopropylmalate isomerase. Both enzymes are known to be involved in the biosynthetic pathways for branched-chain amino acids (BCAAs) (leucine, valine and isoleucine). The B. phymatum ilvE mutant, KM60, was not auxotrophic for BCAAs and could grow well on minimal medium with pyruvate as a carbon source and ammonia as a nitrogen source. However, it grew less efficiently than the wild-type (WT) strain when ammonia was substituted with valine or isoleucine as a nitrogen source. The BCAA aminotransferase activity of KM60 was significantly reduced relative to the WT strain, especially with isoleucine and valine as amino group donors. The C. taiwanensis leuC mutant, KM184-55, could not grow on a minimal medium with pyruvate as a carbon source and ammonia as a nitrogen source, but its growth was restored when leucine was added to the medium. The isopropylmalate isomerase activity of KM184-55 was completely lost compared with the WT strain. Both mutants recovered their respective enzyme activities after complementation with the WT ilvE or leuC genes and were subsequently able to grow as well as their parental strains on minimal medium. They were also able to form nitrogen-fixing nodules on M. pudica. We conclude that the biosynthesis of BCAAs is essential for the free-living growth of betarhizobia, as well as for their ability to form effective symbioses with their host plant.

  15. A novel culture medium designed for the simultaneous enhancement of biomass and lipid production by Chlorella vulgaris UTEX 26.

    PubMed

    Ramírez-López, Citlally; Chairez, Isaac; Fernández-Linares, Luis

    2016-07-01

    A novel culture medium to enhance the biomass and lipid production simultaneously by Chlorella vulgaris UTEX 26 was designed in three stages of optimization. Initially, a culture medium was inferred applying the response surface method to adjust six factors [NaNO3, NH4HCO3, MgSO4·7H2O, KH2PO4, K2HPO4 and (NH4)2HPO4], which were selected on the basement of BBM (Bold's Basal Medium) and HAMGM (Highly Assimilable Minimal Growth Medium) culture media. Afterwards, the nitrogen source compound was optimized to reduce both, ammonium and nitrate concentrations. As result of the optimization process, the proposed culture medium improved 40% the biomass (0.73gL(-1)) compared with the BBM medium and 85% the lipid concentration (281mgL(-1)), with respect to HAMGM medium. Some culture media components concentrations were reduced up to 50%. Gas chromatography analysis revealed that C16:0, C18:0, C18:1, C18:2 and C18:3 were the major fatty acids produced by C. vulgaris UTEX 26. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Investigation of the Klinkenberg effect in a micro/nanoporous medium by direct simulation Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Yang, Guang; Weigand, Bernhard

    2018-04-01

    The pressure-driven gas transport characteristics through a porous medium consisting of arrays of discrete elements is investigated by using the direct simulation Monte Carlo (DSMC) method. Different porous structures are considered, accounting for both two- and three-dimensional arrangements of basic microscale and nanoscale elements. The pore scale flow patterns in the porous medium are obtained, and the Knudsen diffusion in the pores is studied in detail for slip and transition flow regimes. A new effective pore size of the porous medium is defined, which is a function of the porosity, the tortuosity, the contraction factor, and the intrinsic permeability of the porous medium. It is found that the Klinkenberg effect in different porous structures can be fully described by the Knudsen number characterized by the effective pore size. The accuracies of some widely used Klinkenberg correlations are evaluated by the present DSMC results. It is also found that the available correlations for apparent permeability, most of which are derived from simple pipe or channel flows, can still be applicative for more complex porous media flows, by using the effective pore size defined in this study.

  17. Many Denjoy minimal sets for monotone recurrence relations

    NASA Astrophysics Data System (ADS)

    Wang, Ya-Nan; Qin, Wen-Xin

    2014-09-01

    We extend Mather's work (1985 Comment. Math. Helv. 60 508-57) to high-dimensional cylinder maps defined by monotone recurrence relations, e.g. the generalized Frenkel-Kontorova model with finite range interactions. We construct uncountably many Denjoy minimal sets provided that the Birkhoff minimizers with some irrational rotation number ω do not form a foliation.

  18. Effects of exercise and manual therapy on pain associated with hip osteoarthritis: a systematic review and meta-analysis.

    PubMed

    Beumer, Lucy; Wong, Jennie; Warden, Stuart J; Kemp, Joanne L; Foster, Paul; Crossley, Kay M

    2016-04-01

    To explore the effects of exercise (water-based or land-based) and/or manual therapies on pain in adults with clinically and/or radiographically diagnosed hip osteoarthritis (OA). A systematic review and meta-analysis was performed, with patient reported pain assessed using a visual analogue scale (VAS) or the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain subscale. Data were grouped by follow-up time (0-3 months=short term; 4-12 months=medium term and; >12 months=long term), and standardised mean differences (SMD) with 95% CIs were used to establish intervention effect sizes. Study quality was assessed using modified PEDro scores. 19 trials were included. Four studies showed short-term benefits favouring water-based exercise over minimal control using the WOMAC pain subscale (SMD -0.53, 95% CI -0.96 to -0.10). Six studies supported a short-term benefit of land-based exercise compared to minimal control on VAS assessed pain (SMD -0.49, 95% CI -0.70 to -0.29). There were no medium (SMD -0.23, 95% CI -0.48 to 0.03) or long (SMD -0.22, 95% CI -0.51 to 0.06) term benefits of exercise therapy, or benefit of combining exercise therapy with manual therapy (SMD -0.38, 95% CI -0.88 to 0.13) when compared to minimal control. Best available evidence indicates that exercise therapy (whether land-based or water-based) is more effective than minimal control in managing pain associated with hip OA in the short term. Larger high-quality RCTs are needed to establish the effectiveness of exercise and manual therapies in the medium and long term. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  19. Diode end pumped laser and harmonic generator using same

    NASA Technical Reports Server (NTRS)

    Byer, Robert L. (Inventor); Dixon, George J. (Inventor); Kane, Thomas J. (Inventor)

    1988-01-01

    A second harmonic, optical generator is disclosed in which a laser diode produces an output pumping beam which is focused by means of a graded, refractive index rod lens into a rod of lasant material, such as Nd:YAG, disposed within an optical resonator to pump the lasant material and to excite the optical resonator at a fundamental wavelength. A non-linear electro-optic material such as MgO:LiNbO.sub.3 is coupled to the excited, fundamental mode of the optical resonator to produce a non-linear interaction with the fundamental wavelength producing a harmonic. In one embodiment, the gain medium and the non-linear material are disposed within an optical resonator defined by a pair of reflectors, one of which is formed on a face of the gain medium and the second of which is formed on a face of the non-linear medium. In another embodiment, the non-linear, electro-optic material is doped with the lasant ion such that the gain medium and the non-linear doubling material are co-extensive in volume. In another embodiment, a non-linear, doubling material is disposed in an optical resonator external of the laser gai medium for improved stability of the second harmonic generation process. In another embodiment, the laser gain medium andthe non-linear material are bonded together by means of an optically transparent cement to form a mechanically stable, monolithic structure. In another embodiment, the non-linear material has reflective faces formed thereon to define a ring resonator to decouple reflections from the non-linear medium back to the gain medium for improved stability.

  20. Solids-based concentrated solar power receiver

    DOEpatents

    None

    2018-04-10

    A concentrated solar power (CSP) system includes channels arranged to convey a flowing solids medium descending under gravity. The channels form a light-absorbing surface configured to absorb solar flux from a heliostat field. The channels may be independently supported, for example by suspension, and gaps between the channels are sized to accommodate thermal expansion. The light absorbing surface may be sloped so that the inside surfaces of the channels proximate to the light absorbing surface define downward-slanting channel floors, and the flowing solids medium flows along these floors. Baffles may be disposed inside the channels and oriented across the direction of descent of the flowing solids medium. The channels may include wedge-shaped walls forming the light-absorbing surface and defining multiple-reflection light paths for solar flux from the heliostat field incident on the light-absorbing surface.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Costa, David A.; Cournoyer, Michael E.; Merhege, James F.

    Criticality is the state of a nuclear chain reacting medium when the chain reaction is just self-sustaining (or critical). Criticality is dependent on nine interrelated parameters. Moreover, we design criticality safety controls in order to constrain these parameters to minimize fissions and maximize neutron leakage and absorption in other materials, which makes criticality more difficult or impossible to achieve. We present the consequences of criticality accidents are discussed, the nine interrelated parameters that combine to affect criticality are described, and criticality safety controls used to minimize the likelihood of a criticality accident are presented.

  2. Metabolic Genetic Screens Reveal Multidimensional Regulation of Virulence Gene Expression in Listeria monocytogenes and an Aminopeptidase That Is Critical for PrfA Protein Activation.

    PubMed

    Friedman, Sivan; Linsky, Marika; Lobel, Lior; Rabinovich, Lev; Sigal, Nadejda; Herskovits, Anat A

    2017-06-01

    Listeria monocytogenes is an environmental saprophyte and intracellular bacterial pathogen. Upon invading mammalian cells, the bacterium senses abrupt changes in its metabolic environment, which are rapidly transduced to regulation of virulence gene expression. To explore the relationship between L. monocytogenes metabolism and virulence, we monitored virulence gene expression dynamics across a library of genetic mutants grown under two metabolic conditions known to activate the virulent state: charcoal-treated rich medium containing glucose-1-phosphate and minimal defined medium containing limiting concentrations of branched-chain amino acids (BCAAs). We identified over 100 distinct mutants that exhibit aberrant virulence gene expression profiles, the majority of which mapped to nonessential metabolic genes. Mutants displayed enhanced, decreased, and early and late virulence gene expression profiles, as well as persistent levels, demonstrating a high plasticity in virulence gene regulation. Among the mutants, one was noteworthy for its particularly low virulence gene expression level and mapped to an X-prolyl aminopeptidase (PepP). We show that this peptidase plays a role in posttranslational activation of the major virulence regulator, PrfA. Specifically, PepP mediates recruitment of PrfA to the cytoplasmic membrane, a step identified as critical for PrfA protein activation. This study establishes a novel step in the complex mechanism of PrfA activation and further highlights the cross regulation of metabolism and virulence. Copyright © 2017 American Society for Microbiology.

  3. The effect of "single" vs "double" eyelids on the perceived attractiveness of Chinese women.

    PubMed

    Hwang, Harry S; Spiegel, Jeffrey H

    2014-03-01

    A well-defined supratarsal crease has often been considered attractive, representing a significant component in a beautiful upper eyelid. Approximately 50% of East and Southeast Asian women are born with either a minimal or absent supratarsal eyelid crease. Among people of Chinese descent, the creation of a supratarsal crease ("double" eyelid blepharoplasty) is the most common cosmetic surgical procedure, but no comparative study has assessed the height by which an upper eyelid crease is deemed most attractive and depending on cultural background. The authors assess how attractiveness is interpreted by different cultural groups to determine whether double-eyelid blepharoplasty enhances attractiveness according to both Chinese and non-Chinese observers. Facial photographs were taken of 19 women of Chinese descent. The photographs were enhanced with computer imaging software to generate 3 additional pictures, depicting low, medium, and high upper eyelid creases on each model. Via an Internet-based survey tool, Chinese and non-Chinese observers were asked to rate the attractiveness of the faces with each potential eyelid position. (Surveys are available online at www.aestheticsurgeryjournal.com, as Appendix 1 and Appendix 2.) Both Chinese and non-Chinese observers considered the medium-height upper eyelid crease most attractive (P < .00001). An absent upper eyelid crease was deemed the least attractive (P < .00001). These preference data for eyelid height can be used to better counsel patients on perceived attractiveness and expectations for surgical results, since these results further elucidate which facial features are universally considered attractive.

  4. Physiologic Determinants of Radiation Resistance in Deinococcus radiodurans

    PubMed Central

    Venkateswaran, Amudhan; McFarlan, Sara C.; Ghosal, Debabrota; Minton, Kenneth W.; Vasilenko, Alexander; Makarova, Kira; Wackett, Lawrence P.; Daly, Michael J.

    2000-01-01

    Immense volumes of radioactive wastes, which were generated during nuclear weapons production, were disposed of directly in the ground during the Cold War, a period when national security priorities often surmounted concerns over the environment. The bacterium Deinococcus radiodurans is the most radiation-resistant organism known and is currently being engineered for remediation of the toxic metal and organic components of these environmental wastes. Understanding the biotic potential of D. radiodurans and its global physiological integrity in nutritionally restricted radioactive environments is important in development of this organism for in situ bioremediation. We have previously shown that D. radiodurans can grow on rich medium in the presence of continuous radiation (6,000 rads/h) without lethality. In this study we developed a chemically defined minimal medium that can be used to analyze growth of this organism in the presence and in the absence of continuous radiation; whereas cell growth was not affected in the absence of radiation, cells did not grow and were killed in the presence of continuous radiation. Under nutrient-limiting conditions, DNA repair was found to be limited by the metabolic capabilities of D. radiodurans and not by any nutritionally induced defect in genetic repair. The results of our growth studies and analysis of the complete D. radiodurans genomic sequence support the hypothesis that there are several defects in D. radiodurans global metabolic regulation that limit carbon, nitrogen, and DNA metabolism. We identified key nutritional constituents that restore growth of D. radiodurans in nutritionally limiting radioactive environments. PMID:10831446

  5. Targeted gene disruption of glycerol-3-phosphate dehydrogenase in Colletotrichum gloeosporioides reveals evidence that glycerol is a significant transferred nutrient from host plant to fungal pathogen.

    PubMed

    Wei, Yangdou; Shen, Wenyun; Dauk, Melanie; Wang, Feng; Selvaraj, Gopalan; Zou, Jitao

    2004-01-02

    Unidirectional transfer of nutrients from plant host to pathogen represents a most revealing aspect of the parasitic lifestyle of plant pathogens. Whereas much effort has been focused on sugars and amino acids, the identification of other significant metabolites is equally important for comprehensive characterization of metabolic interactions between plants and biotrophic fungal pathogens. Employing a strategy of targeted gene disruption, we generated a mutant strain (gpdhDelta) defective in glycerol-3-phosphate dehydrogenase in a hemibiotrophic plant pathogen, Colletotrichum gloeosporioides f.sp. malvae. The gpdhDelta strain had severe defects in carbon utilization as it could use neither glucose nor amino acids for sustained growth. Although the mutant mycelia were able to grow on potato dextrose agar medium, they displayed arrhythmicity in growth and failure to conidiate. The metabolic defect of gpdhDelta could be entirely ameliorated by glycerol in chemically defined minimal medium. Furthermore, glycerol was the one and only metabolite that could restore rhythmic growth and conidiation of gpdhDelta. Despite the profound defects in carbon source utilization, in planta the gpdhDelta strain exhibited normal pathogenicity, proceeded normally in its life cycle, and produced abundant conidia. Analysis of plant tissues at the peripheral zone of fungal infection sites revealed a time-dependent reduction in glycerol content. This study provides strong evidence for a role of glycerol as a significant transferred metabolite from plant to fungal pathogen.

  6. Studies of the Acetate Kinase-Phosphotransacetylase and the Butanediol-Forming Systems in Aerobacter aerogenes

    PubMed Central

    Brown, T. D. K.; Pereira, C. R. S.; Størmer, F. C.

    1972-01-01

    Mutants of Aerobacter aerogenes devoid of acetate kinase and phosphotransacetylase activities were isolated by selection for resistance to fluoroacetate on lactate medium. The mutants were used to study the role of the acetate kinase-phosphotransacetylase system in growth on acetate and glucose. Acetate kinase-negative and phosphotransacetylase-negative mutants were unable to grow on acetate minimal medium. Their growth rates on glucose minimal medium were identical with that of the parent strain under aerobic conditions, but lower growth rates were observed in the mutant strains during anaerobic growth on glucose medium. The mutants were unable to incorporate [2-14C]-acetate rapidly while growing on glycerol. Variations in acetate kinase and phosphotransacetylase levels during growth on glucose were studied. The specific activities of the enzymes increased approximately fivefold during aerobic growth on glucose in batch culture. The enzyme levels were also studied during anaerobic growth on glucose at constant pH (pH 5.8 and 7.0). Smaller increases in specific activities were found under these conditions. The role of acetate in the induction of the diacetyl (acetoin) reductase was investigated using a mutant deficient in both acetate kinase and phosphotransacetylase. The effect of pH on the induction of this enzyme during growth on glucose under anaerobic conditions was tested. The data support the idea that free acetic acid is the inducer for the enzymes of the butanediol-forming pathway in A. aerogenes. PMID:4640502

  7. The growth of Paracoccus halodenitrificans in a defined medium

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Tomlinson, G. A.

    1984-01-01

    A synthetic medium, consisting of inorganic salts and any of a number of carbon sources, supported the aerobic growth of Paracoccus halodenitrificans when supplemented with thiamine. The same medium plus a nitrogenous oxide supported anaerobic growth when additionally supplemented with methionine. The observation that vitamin B12 or betaine replaced methionine suggested that P. halodenitrificans had a defect in the cobalamin dependent pathway for methionine biosynthesis, as well as the inability to synthesize betanine when growing anaerobically.

  8. The growth of paracoccus halodenitrificans in a defined medium

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Tomlinson, G. A.

    1983-01-01

    A synthetic medium, consisting of inorganic salts and any of a number of carbon sources, supported the aerobic growth of Paracoccus halodenitrificans when supplemented with thiamine. The same medium plus a nitrogenous oxide supported anaerobic growth when additionally supplemented with methionine. The observation that vitamin B12 or betaine replaced methionine suggested that P. halodenitrificans had a defect in the cobalamin dependent pathway for methionine biosynthesis, as well as the inability to synthesize betaine when growing anaerobically.

  9. Stimulation of GABA-Induced Ca2+ Influx Enhances Maturation of Human Induced Pluripotent Stem Cell-Derived Neurons

    PubMed Central

    Rushton, David J.; Mattis, Virginia B.; Svendsen, Clive N.; Allen, Nicholas D.; Kemp, Paul J.

    2013-01-01

    Optimal use of patient-derived, induced pluripotent stem cells for modeling neuronal diseases is crucially dependent upon the proper physiological maturation of derived neurons. As a strategy to develop defined differentiation protocols that optimize electrophysiological function, we investigated the role of Ca2+ channel regulation by astrocyte conditioned medium in neuronal maturation, using whole-cell patch clamp and Ca2+ imaging. Standard control medium supported basic differentiation of induced pluripotent stem cell-derived neurons, as assayed by the ability to fire simple, single, induced action potentials. In contrast, treatment with astrocyte conditioned medium elicited complex and spontaneous neuronal activity, often with rhythmic and biphasic characteristics. Such augmented spontaneous activity correlated with astrocyte conditioned medium-evoked hyperpolarization and was dependent upon regulated function of L-, N- and R-type Ca2+ channels. The requirement for astrocyte conditioned medium could be substituted by simply supplementing control differentiation medium with high Ca2+ or γ-amino butyric acid (GABA). Importantly, even in the absence of GABA signalling, opening Ca2+ channels directly using Bay K8644 was able to hyperpolarise neurons and enhance excitability, producing fully functional neurons. These data provide mechanistic insight into how secreted astrocyte factors control differentiation and, importantly, suggest that pharmacological modulation of Ca2+ channel function leads to the development of a defined protocol for improved maturation of induced pluripotent stem cell-derived neurons. PMID:24278369

  10. High power regenerative laser amplifier

    DOEpatents

    Miller, John L.; Hackel, Lloyd A.; Dane, Clifford B.; Zapata, Luis E.

    1994-01-01

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

  11. High power regenerative laser amplifier

    DOEpatents

    Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

    1994-02-08

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

  12. Quality assurance of multiport image-guided minimally invasive surgery at the lateral skull base.

    PubMed

    Nau-Hermes, Maria; Schmitt, Robert; Becker, Meike; El-Hakimi, Wissam; Hansen, Stefan; Klenzner, Thomas; Schipper, Jörg

    2014-01-01

    For multiport image-guided minimally invasive surgery at the lateral skull base a quality management is necessary to avoid the damage of closely spaced critical neurovascular structures. So far there is no standardized method applicable independently from the surgery. Therefore, we adapt a quality management method, the quality gates (QG), which is well established in, for example, the automotive industry and apply it to multiport image-guided minimally invasive surgery. QG divide a process into different sections. Passing between sections can only be achieved if previously defined requirements are fulfilled which secures the process chain. An interdisciplinary team of otosurgeons, computer scientists, and engineers has worked together to define the quality gates and the corresponding criteria that need to be fulfilled before passing each quality gate. In order to evaluate the defined QG and their criteria, the new surgery method was applied with a first prototype at a human skull cadaver model. We show that the QG method can ensure a safe multiport minimally invasive surgical process at the lateral skull base. Therewith, we present an approach towards the standardization of quality assurance of surgical processes.

  13. Quality Assurance of Multiport Image-Guided Minimally Invasive Surgery at the Lateral Skull Base

    PubMed Central

    Nau-Hermes, Maria; Schmitt, Robert; Becker, Meike; El-Hakimi, Wissam; Hansen, Stefan; Klenzner, Thomas; Schipper, Jörg

    2014-01-01

    For multiport image-guided minimally invasive surgery at the lateral skull base a quality management is necessary to avoid the damage of closely spaced critical neurovascular structures. So far there is no standardized method applicable independently from the surgery. Therefore, we adapt a quality management method, the quality gates (QG), which is well established in, for example, the automotive industry and apply it to multiport image-guided minimally invasive surgery. QG divide a process into different sections. Passing between sections can only be achieved if previously defined requirements are fulfilled which secures the process chain. An interdisciplinary team of otosurgeons, computer scientists, and engineers has worked together to define the quality gates and the corresponding criteria that need to be fulfilled before passing each quality gate. In order to evaluate the defined QG and their criteria, the new surgery method was applied with a first prototype at a human skull cadaver model. We show that the QG method can ensure a safe multiport minimally invasive surgical process at the lateral skull base. Therewith, we present an approach towards the standardization of quality assurance of surgical processes. PMID:25105146

  14. Optimization of Culture Medium Enhances Viable Biomass Production and Biocontrol Efficacy of the Antagonistic Yeast, Candida diversa.

    PubMed

    Liu, Jia; Li, Guangkun; Sui, Yuan

    2017-01-01

    Viable biomass production is a key determinant of suitability of antagonistic yeasts as potential biocontrol agents. This study investigated the effects of three metal ions (magnesium, ferrous, and zinc) on biomass production and viability of the antagonistic yeast, Candida diversa . Using response surface methodology to optimize medium components, a maximum biomass was obtained, when the collective Mg 2+ , Fe 2+ , and Zn 2+ concentrations were adjusted in a minimal mineral (MM) medium. Compared with the unmodified MM, and three ion-deficient MM media, yeast cells cultured in the three ion-modified MM medium exhibited a lower level of cellular oxidative damage, and a higher level of antioxidant enzyme activity. A biocontrol assay indicated that C. diversa grown in the ion-modified MM exhibited the greatest level of control of gray mold on apple fruit. These results provide new information on culture medium optimization to grow yeast antagonists in order to improve biomass production and biocontrol efficacy.

  15. Optimization of Culture Medium Enhances Viable Biomass Production and Biocontrol Efficacy of the Antagonistic Yeast, Candida diversa

    PubMed Central

    Liu, Jia; Li, Guangkun; Sui, Yuan

    2017-01-01

    Viable biomass production is a key determinant of suitability of antagonistic yeasts as potential biocontrol agents. This study investigated the effects of three metal ions (magnesium, ferrous, and zinc) on biomass production and viability of the antagonistic yeast, Candida diversa. Using response surface methodology to optimize medium components, a maximum biomass was obtained, when the collective Mg2+, Fe2+, and Zn2+ concentrations were adjusted in a minimal mineral (MM) medium. Compared with the unmodified MM, and three ion-deficient MM media, yeast cells cultured in the three ion-modified MM medium exhibited a lower level of cellular oxidative damage, and a higher level of antioxidant enzyme activity. A biocontrol assay indicated that C. diversa grown in the ion-modified MM exhibited the greatest level of control of gray mold on apple fruit. These results provide new information on culture medium optimization to grow yeast antagonists in order to improve biomass production and biocontrol efficacy. PMID:29089939

  16. Mass Media Preference Patterns: A Cross-Media Study.

    ERIC Educational Resources Information Center

    Williams, Dwight A., Jr.

    This study defined "preference types" (types of people who use various media) and looked at constructs people used in deciding their preferences. Preferences in one medium were compared with preferences in another medium for the same group of people. The six media studied were television, radio, movies, magazines, brand commercials, and political…

  17. Internet Shopping Behavior of College of Education Students

    ERIC Educational Resources Information Center

    Kiyici, Mubin

    2012-01-01

    Internet is an important facilitator for human and humans use this medium almost every phase. As a shopping medium, internet attract human so attract researcher. Younger people can adapt newer technologies so they can adapt internet as shopping tool. In this research it is tried to define college of education students' online shopping behavior and…

  18. Reading on Paper and Digitally: What the Past Decades of Empirical Research Reveal

    ERIC Educational Resources Information Center

    Singer, Lauren M.; Alexander, Patricia A.

    2017-01-01

    This systematic literature review was undertaken primarily to examine the role that print and digitally mediums play in text comprehension. Overall, results suggest that medium plays an influential role under certain text or task conditions or for certain readers. Additional goals were to identify how researchers defined and measured…

  19. Quantum description of a field in macroscopic electrodynamics and photon properties in transparent media

    NASA Astrophysics Data System (ADS)

    Toptygin, I. N.

    2017-12-01

    Applying a quantum mechanical treatment to a high-frequency macroscopic electromagnetic field and radiative phenomena in a medium, we construct quantum operators for energy-momentum tensor components in dispersive media and find their eigenvalues, which are different in the Minkowski and Abraham representations. It is shown that the photon momentum in a medium resulting from the quantization of the vector potential differs from that defined from Abraham’s symmetric energy-momentum-tensor but is equal to the momentum defined from the Minkowski tensor. A similar result is obtained by calculating the intrinsic angular momentum (spin) of an electro-magnetic field in the medium. Only the Minkowski tensor leads to the experimentally confirmed spin values that are multiples of ħ, providing the grounds for choosing the Minkowski representation as the proper form for the momentum density of a transverse electromagnetic field in a transparent medium, in both classical and quantum descriptions of the field. The Abraham representation is unsuitable for this purpose and leads to contradictions. The conclusion drawn does not apply to quasistatic and static fields.

  20. Medium Effects on Minimum Inhibitory Concentrations of Nylon-3 Polymers against E. coli

    PubMed Central

    Choi, Heejun; Chakraborty, Saswata; Liu, Runhui; Gellman, Samuel H.; Weisshaar, James C.

    2014-01-01

    Minimum inhibitory concentrations (MICs) against E. coli were measured for three nylon-3 polymers using Luria-Bertani broth (LB), brain-heart infusion broth (BHI), and a chemically defined complete medium (EZRDM). The polymers differ in the ratio of hydrophobic to cationic subunits. The cationic homopolymer is inert against E. coli in BHI and LB, but becomes highly potent in EZRDM. A mixed hydrophobic/cationic polymer with a hydrophobic t-butylbenzoyl group at its N-terminus is effective in BHI, but becomes more effective in EZRDM. Supplementation of EZRDM with the tryptic digest of casein (often found in LB) recapitulates the LB and BHI behavior. Additional evidence suggests that polyanionic peptides present in LB and BHI may form electrostatic complexes with cationic polymers, decreasing activity by diminishing binding to the anionic lipopolysaccharide layer of E. coli. In contrast, two natural antimicrobial peptides show no medium effects. Thus, the use of a chemically defined medium helps to reveal factors that influence antimicrobial potency of cationic polymers and functional differences between these polymers and evolved antimicrobial peptides. PMID:25153714

  1. The down-regulation of the mitogenic fibrinogen receptor (MFR) in serum-containing medium does not occur in defined medium.

    PubMed

    Levesque, J P; Hatzfeld, A; Domart, I; Hatzfeld, J

    1990-02-01

    Normal human hemopoietic cells such as early bone marrow progenitors, or lymphoma-derived cell lines such as Raji or JM cells, possess a low-affinity receptor specific for fibrinogen. This receptor triggers a mitogenic effect. It differs from the glycoprotein IIb-IIIa which is involved in fibrinogen-induced platelet aggregation. We demonstrate here that this mitogenic fibrinogen receptor (MFR) can be internalized or reexpressed, depending on culture conditions. Internalization was temperature-dependent. At 37 degrees C in the presence of cycloheximide or actinomycin D, the half-life of cell surface MFRs was 2 h, independent of receptor occupancy. Binding of fibrinogen to the MFR resulted in a down-regulation which was fibrinogen dose-dependent. This occurred in serum-supplemented medium but not in defined medium supplemented with fatty acids. Reexpression of MFRs could be induced in 28 to 42 h by serum removal. The down-regulation of mitogenic receptors in plasma or serum could explain why normal cells do not proliferate in the peripheral blood.

  2. Tween 80 effect on glucosyltransferase synthesis by Streptococcus salivarius.

    PubMed Central

    Wittenberger, C L; Beaman, A J; Lee, L N

    1978-01-01

    Streptococcus salivarius (ATCC 25975) produced very low or nondetectable amounts of the extracellular enzyme glucosyltransferase (GTase) when grown in a chemically defined medium. The addition of Tween 80 to this medium resulted in the production of markedly enhanced levels of the enzyme. Oleic acid, the methyl ester of oleic acid, and sucrose each could not substitute for Tween 80 in this regard. The surfactant had no direct activating effect on performed enzyme activity. Tween 80 also stimulated the production of GTase by concentrated cells suspended in defined medium during a time when no measurable growth occurred. Under these conditions, the stimulatory effect of Tween 80 was blocked by chloramphenicol. It was further found that the surfactant dramatically stimulated the differential rate of GTase synthesis. These and other data strongly suggest that Tween 80 stimulates the production of extracellular GTase by acting either directly or indirectly at the level of enzyme synthesis. PMID:618839

  3. Magnitude of pseudopotential localization errors in fixed node diffusion quantum Monte Carlo

    DOE PAGES

    Kent, Paul R.; Krogel, Jaron T.

    2017-06-22

    Growth in computational resources has lead to the application of real space diffusion quantum Monte Carlo to increasingly heavy elements. Although generally assumed to be small, we find that when using standard techniques, the pseudopotential localization error can be large, on the order of an electron volt for an isolated cerium atom. We formally show that the localization error can be reduced to zero with improvements to the Jastrow factor alone, and we define a metric of Jastrow sensitivity that may be useful in the design of pseudopotentials. We employ an extrapolation scheme to extract the bare fixed node energymore » and estimate the localization error in both the locality approximation and the T-moves schemes for the Ce atom in charge states 3+/4+. The locality approximation exhibits the lowest Jastrow sensitivity and generally smaller localization errors than T-moves although the locality approximation energy approaches the localization free limit from above/below for the 3+/4+ charge state. We find that energy minimized Jastrow factors including three-body electron-electron-ion terms are the most effective at reducing the localization error for both the locality approximation and T-moves for the case of the Ce atom. Less complex or variance minimized Jastrows are generally less effective. Finally, our results suggest that further improvements to Jastrow factors and trial wavefunction forms may be needed to reduce localization errors to chemical accuracy when medium core pseudopotentials are applied to heavy elements such as Ce.« less

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kent, Paul R.; Krogel, Jaron T.

    Growth in computational resources has lead to the application of real space diffusion quantum Monte Carlo to increasingly heavy elements. Although generally assumed to be small, we find that when using standard techniques, the pseudopotential localization error can be large, on the order of an electron volt for an isolated cerium atom. We formally show that the localization error can be reduced to zero with improvements to the Jastrow factor alone, and we define a metric of Jastrow sensitivity that may be useful in the design of pseudopotentials. We employ an extrapolation scheme to extract the bare fixed node energymore » and estimate the localization error in both the locality approximation and the T-moves schemes for the Ce atom in charge states 3+/4+. The locality approximation exhibits the lowest Jastrow sensitivity and generally smaller localization errors than T-moves although the locality approximation energy approaches the localization free limit from above/below for the 3+/4+ charge state. We find that energy minimized Jastrow factors including three-body electron-electron-ion terms are the most effective at reducing the localization error for both the locality approximation and T-moves for the case of the Ce atom. Less complex or variance minimized Jastrows are generally less effective. Finally, our results suggest that further improvements to Jastrow factors and trial wavefunction forms may be needed to reduce localization errors to chemical accuracy when medium core pseudopotentials are applied to heavy elements such as Ce.« less

  5. Improved Medium for Selecting Nitrate-Nonutilizing (nit) Mutants of Verticillium dahliae.

    PubMed

    Korolev, N; Katan, T

    1997-10-01

    ABSTRACT Nitrate-nonutilizing (nit) mutants are commonly used to determine vegetative compatibility between isolates of Verticillium dahliae by complementation (heterokaryon) testing. These mutants emerge spontaneously as chlorate-resistant sectors growing out of partially restricted, wild-type colonies on chlorate-amended media. The commonly used chlorate media are based on minimal medium (MMC) or cornmeal agar (CMC), amended with potassium chlorate. nit mutants recovered on these media constituted 10 to 36%(on MMC) and 25 to 45%(on CMC) of the apparently resistant sectors. An improved water agar chlorate medium (WAC) is described that is more effective for selecting chlorate-resistant nit mutants. WAC medium consists of agar (2%), glucose (0.02%), and potassium chlorate (2 to 5%). On WAC, growth of most V. dahliae isolates was strongly inhibited, and 66 to 100%(average >80%) of the chlorate-resistant sectors formed were nit mutants. Most mutants were characterized as nit1, and about 6% as NitM.

  6. Potting procedure for electronic components

    NASA Technical Reports Server (NTRS)

    Rubino, A. G.; Zimmerman, J.

    1977-01-01

    Potting process is modified to effect a match more closely between embedded electronic components, potting mediums, and thermal environment. Application of room-temperature vulcanizing silicone rubber band cured in modified thermal cycle minimizes coil-to-resin adhesion and thus lowers stresses between transformer and potting compound.

  7. The development of internet based ship design support system for small and medium sized shipyards

    NASA Astrophysics Data System (ADS)

    Shin, Sung-Chul; Lee, Soon-Sup; Kang, Dong-Hoon; Lee, Kyung-Ho

    2012-03-01

    In this paper, a prototype of ship basic planning system is implemented for the small and medium sized shipyards based on the internet technology and concurrent engineering concept. The system is designed from the user requirements. Consequently, standardized development environment and tools are selected. These tools are used for the system development to define and evaluate core application technologies. The system will contribute to increasing competitiveness of small and medium sized shipyards in the 21st century industrial en-vironment.

  8. Production of High-Viscosity Whey Broths by a Lactose-Utilizing Xanthomonas campestris Strain.

    PubMed

    Schwartz, R D; Bodie, E A

    1985-12-01

    Xanthomonas campestris BB-1L was isolated by enrichment and selection by serial passage in a lactose-minimal medium. When BB-1L was subsequently grown in medium containing only 4% whey and 0.05% yeast extract, the lactose was consumed and broth viscosities greater than 500 cps at a 12 s shear rate were produced. Prolonged maintenance in whey resulted in the loss of the ability of BB-1L to produce viscous broths in whey, indicating a reversion to preferential growth on whey protein, like the parent strain.

  9. Biodegradation of indole at high concentration by persolvent fermentation with Pseudomonas sp. ST-200.

    PubMed

    Doukyu, N; Aono, R

    1997-05-01

    Pseudomonas sp. strain ST-200 grew on indole as a sole carbon source. The minimal inhibitory concentration of indole was 0.3 mg/ml for ST-200. However, ST-200 grew in a persolvent fermentation system containing a large amount of indole (a medium containing 20% by vol. diphenylmethane and 4 mg/ml indole), because most of the indole was partitioned in the organic solvent layer. When the organism was grown in the medium containing indole at 1 mg/ml in the presence of diphenylmethane, more than 98% of the indole was consumed after 48h. Isatic acid (0.4 mg/ml) and isatin (0.03 mg/ml) were produced as the metabolites in the aqueous medium layer.

  10. Frequency-domain method for measuring spectral properties in multiple-scattering media: methemoglobin absorption spectrum in a tissuelike phantom

    NASA Astrophysics Data System (ADS)

    Fishkin, Joshua B.; So, Peter T. C.; Cerussi, Albert E.; Gratton, Enrico; Fantini, Sergio; Franceschini, Maria Angela

    1995-03-01

    We have measured the optical absorption and scattering coefficient spectra of a multiple-scattering medium (i.e., a biological tissue-simulating phantom comprising a lipid colloid) containing methemoglobin by using frequency-domain techniques. The methemoglobin absorption spectrum determined in the multiple-scattering medium is in excellent agreement with a corrected methemoglobin absorption spectrum obtained from a steady-state spectrophotometer measurement of the optical density of a minimally scattering medium. The determination of the corrected methemoglobin absorption spectrum takes into account the scattering from impurities in the methemoglobin solution containing no lipid colloid. Frequency-domain techniques allow for the separation of the absorbing from the scattering properties of multiple-scattering media, and these techniques thus provide an absolute

  11. Inducible in vivo DNA footprints define sequences necessary for UV light activation of the parsley chalcone synthase gene.

    PubMed Central

    Schulze-Lefert, P; Dangl, J L; Becker-André, M; Hahlbrock, K; Schulz, W

    1989-01-01

    We began characterization of the protein--DNA interactions necessary for UV light induced transcriptional activation of the gene encoding chalcone synthase (CHS), a key plant defense enzyme. Three light dependent in vivo footprints appear on a 90 bp stretch of the CHS promoter with a time course correlated with the onset of CHS transcription. We define a minimal light responsive promoter by functional analysis of truncated CHS promoter fusions with a reporter gene in transient expression experiments in parsley protoplasts. Two of the three footprinted sequence 'boxes' reside within the minimal promoter. Replacement of 10 bp within either of these 'boxes' leads to complete loss of light responsiveness. We conclude that these sequences define the necessary cis elements of the minimal CHS promoter's light responsive element. One of the functionally defined 'boxes' is homologous to an element implicated in regulation of genes involved in photosynthesis. These data represent the first example in a plant defense gene of an induced change in protein--DNA contacts necessary for transcriptional activation. Also, our data argue strongly that divergent light induced biosynthetic pathways share common regulatory units. Images PMID:2566481

  12. The Proportion of Minimally Verbal Children with Autism Spectrum Disorder in a Community-Based Early Intervention Programme

    ERIC Educational Resources Information Center

    Rose, V.; Trembath, D.; Keen, D.; Paynter, J.

    2016-01-01

    Background: Estimates of the proportion of children with autism spectrum disorder (ASD) who are minimally verbal vary from 25% to 35%. However, there is a lack of consensus in defining minimally verbal and few detailed reports of communication outcomes for these children following intervention. The aim of this study was to explore how minimally…

  13. Understanding Definitions of Minimally Verbal across Instruments: Evidence for Subgroups within Minimally Verbal Children and Adolescents with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Bal, Vanessa Hus; Katz, Terry; Bishop, Somer L.; Krasileva, Kate

    2016-01-01

    Background: Minimally verbal (MV) children with autism spectrum disorder (ASD) are often assumed to be profoundly cognitively impaired and excluded from analyses due to challenges completing standardized testing protocols. A literature aimed at increasing understanding of this subgroup is emerging; however, the many methods used to define MV…

  14. Ozone-augmented percutaneous discectomy: a novel treatment option for refractory discogenic sciatica.

    PubMed

    Crockett, M T; Moynagh, M; Long, N; Kilcoyne, A; Dicker, P; Synnott, K; Eustace, S J

    2014-12-01

    To assess the short and medium-term efficacy and safety of a novel, minimally invasive therapeutic option combining automated percutaneous lumbar discectomy, intradiscal ozone injection, and caudal epidural: ozone-augmented percutaneous discectomy (OPLD). One hundred and forty-seven patients with a clinical and radiological diagnosis of discogenic sciatica who were refractory to initial therapy were included. Fifty patients underwent OPLD whilst 97 underwent a further caudal epidural. Outcomes were evaluated using McNab's score, improvement in visual analogue score (VAS) pain score, and requirement for further intervention. Follow-up occurred at 1 and 6 months, and comparison was made between groups. OPLD achieved successful outcomes in almost three-quarters of patients in the short and medium term. OPLD achieved superior outcomes at 1 and 6 months compared to caudal epidural. There was a reduced requirement for further intervention in the OPLD group. No significant complications occurred in either group. OPLD is a safe and effective treatment for patients with refractory discogenic sciatica in the short and medium term. OPLD has the potential to offer an alternative second-line minimally invasive treatment option that could reduce the requirement for surgery in this patient cohort. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  15. Missense suppression in Coprinus lagopus associated wtih a chromosome duplication.

    PubMed

    Lewis, D; Casselton, L A

    1975-05-01

    Amongst some 70 recessive suppressors of a met-I mutation in Coprinus lagopus, one unstable suppressor was identified. The unstable suppressor, designated sup-6plus, could be maintained on minimal medium, but was lost within 24h on minimal medium containing more than 1-7 p.p.m. DL-methionine or 0-75 p.p.m. L-methionine. Isolation of hyphal tips from the monokaryotic strain carrying sup-6plus yielded three types of colony: the unstable parental type, the stable met-I auxotroph and a stable prototroph which was slow-growing and inhibited by methionine in the growth medium. This stable sup-6plus type was recovered with difficulty by resolving dikaryons formed between the unstable sup-6plus strain and strains carring the wild-type allele of the suppressor gene. From sexual crosses, neither the unstable nor stable sup-6plus type segregated, only the met-I auxotrophic revertant. The unstable sup-6plus strain is thought to have an extra chromosome carrying the sup-6plus mutation. For vigorous growth the wild-type allele, sup-6, is indispensable and would be carried on the homologous chromosome. The selective pressures on different media account for loss of the duplicated chromosomes. The results are interpreted as missense suppression by a mutant of an indispensable tRNA.

  16. Cost-effective defined medium for the production of polyhydroxyalkanoates using agricultural raw materials.

    PubMed

    Suwannasing, Waranya; Imai, Tsuyoshi; Kaewkannetra, Pakawadee

    2015-10-01

    According to the cost of carbon substrate for producing biopolymer of polyhydroxyalkanoates (PHAs) still has a barrier to extend in an industrial scale. The aim of this work was to evaluate the defined PHAs media containing the agricultural raw materials of pineapple and sugarcane to produce PHAs by Bacillus strain. Batch fermentation was carried out in flask scale to compare the efficiency of defined media using statistical methodology. The defined medium 8 of pineapple was achieved the highest PHAs concentration and productivity (1.86 g/L and 0.077 g/Lh). The effect of pH and aeration was extensively studied in a fermentor. The results were revealed that PHAs production would be increased from the condition of uncontrolled pH and at higher aeration rate. The extracted PHAs clearly showed in a homopolymer structure of poly(3-hydroxybutyrate) (PHB) with melting temperature (Tm) of 172°C 54.39% crystallinity. Copyright © 2015. Published by Elsevier Ltd.

  17. Water jacket for solid particle solar receiver

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wasyluk, David T.

    A solar receiver includes: water jacket panels each having a light-receiving side and a back side with a watertight sealed plenum defined in-between; light apertures passing through the watertight sealed plenums to receive light from the light-receiving sides of the water jacket panels; a heat transfer medium gap defined between the back sides of the water jacket panels and a cylindrical back plate; and light channeling tubes optically coupled with the light apertures and extending into the heat transfer medium gap. In some embodiments ends of the light apertures at the light receiving side of the water jacket panel aremore » welded together to define at least a portion of the light-receiving side. A cylindrical solar receiver may be constructed using a plurality of such water jacket panels arranged with their light-receiving sides facing outward.« less

  18. Microgravity alters the physiological characteristics of Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895 under different nutrient conditions.

    PubMed

    Kim, H W; Matin, A; Rhee, M S

    2014-04-01

    The aim of this study is to provide understanding of microgravity effects on important food-borne bacteria, Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895, cultured in nutrient-rich or minimal medium. Physiological characteristics, such as growth (measured by optical density and plating), cell morphology, and pH, were monitored under low-shear modeled microgravity (LSMMG; space conditions) and normal gravity (NG; Earth conditions). In nutrient-rich medium, all strains except ATCC 35150 showed significantly higher optical density after 6 h of culture under LSMMG conditions than under NG conditions (P < 0.05). LSMMG-cultured cells were approximately 1.8 times larger than NG-cultured cells at 24 h; therefore, it was assumed that the increase in optical density was due to the size of individual cells rather than an increase in the cell population. The higher pH of the NG cultures relative to that of the LSMMG cultures suggests that nitrogen metabolism was slower in the latter. After 24 h of culturing in minimal media, LSMMG-cultured cells had an optical density 1.3 times higher than that of NG-cultured cells; thus, the higher optical density in the LSMMG cultures may be due to an increase in both cell size and number. Since bacteria actively grew under LSMMG conditions in minimal medium despite the lower pH, it is of some concern that LSMMG-cultured E. coli O157:H7 may be able to adapt well to acidic environments. These changes may be caused by changes in nutrient metabolism under LSMMG conditions, although this needs to be demonstrated in future studies.

  19. Growth and differentiation of a murine interleukin-3-producing myelomonocytic leukemia cell line in a protein-free chemically defined medium.

    PubMed

    Kajigaya, Y; Ikuta, K; Sasaki, H; Matsuyama, S

    1990-10-01

    We established the continuous growth of WEHI-3B D+ cells in protein-free chemically defined F-12 medium by stepwise decreases in the concentration of fetal calf serum. This cell line, designated as WEHI-3B-Y1, has now been propagated in protein-free F-12 medium for 3 years. The population-doubling time of the cells in culture is about 24 hr. WEHI-3B-Y1 cells are immature undifferentiated cells which show positive staining for naphthol ASD chloroacetate esterase and alpha-naphthyl butyrate esterase and spontaneously exhibit a low level of differentiation to mature granulocytes and macrophages. Medium conditioned by WEHI-3B-Y1 cells stimulated the proliferation of an interleukin-3 (IL-3)-dependent FDCP-2 cell line. This conditioned medium was shown to have erythroid burst-promoting activity when assayed using normal murine bone marrow. The colony formation of WEHI-3B-Y1 cells in semi-solid agar culture was not stimulated by purified recombinant human granulocyte colony-stimulating factor (rhG-CSF). However, in the presence of human transferrin, rhG-CSF enhanced the number of colonies of WEHI-3B-Y1 cells but did not induce their differentiation. These results suggest that WEHI-3B-Y1 cells cultured in protein-free medium produced murine IL-3. In addition, human G-CSF enhanced the clonal growth but did not induce the differentiation of WEHI-3B-Y1 cells cultured in serum-free medium.

  20. Culturing Selenastrum capricornutum (Chlorophyta) in a synthetic algal nutrient medium with defined mineral particulates

    USGS Publications Warehouse

    Kuwabara, J.S.; Davis, J.A.; Chang, Cecily C.Y.

    1985-01-01

    Algal nutrient studies in chemically-defined media typically employ a synthetic chelator to prevent iron hydroxide precipitation. Micronutrient-particulate interactions may, however, significantly affect chemical speciation and hence biovailability of these nutrients in natural waters. A technique is described by which Selenastrum capricornutum Printz (Chlorophyta) may be cultured in a medium where trace metal speciation (except iron) is controlled, not by organic chelation, but by sorption onto titanium dioxide. Application of this culturing protocol in conjunction with results from sorption studies of nutrient ions on mineral particles provides a means of studying biological impacts of sorptive processes in aquatic environments. ?? 1985 Dr W. Junk Publishers.

  1. Permeability of model porous medium formed by random discs

    NASA Astrophysics Data System (ADS)

    Gubaidullin, A. A.; Gubkin, A. S.; Igoshin, D. E.; Ignatev, P. A.

    2018-03-01

    Two-dimension model of the porous medium with skeleton of randomly located overlapping discs is proposed. The geometry and computational grid are built in open package Salome. Flow of Newtonian liquid in longitudinal and transverse directions is calculated and its flow rate is defined. The numerical solution of the Navier-Stokes equations for a given pressure drop at the boundaries of the area is realized in the open package OpenFOAM. Calculated value of flow rate is used for defining of permeability coefficient on the base of Darcy law. For evaluating of representativeness of computational domain the permeability coefficients in longitudinal and transverse directions are compered.

  2. A Genome-Scale Metabolic Reconstruction of Mycoplasma genitalium, iPS189

    PubMed Central

    Suthers, Patrick F.; Dasika, Madhukar S.; Kumar, Vinay Satish; Denisov, Gennady; Glass, John I.; Maranas, Costas D.

    2009-01-01

    With a genome size of ∼580 kb and approximately 480 protein coding regions, Mycoplasma genitalium is one of the smallest known self-replicating organisms and, additionally, has extremely fastidious nutrient requirements. The reduced genomic content of M. genitalium has led researchers to suggest that the molecular assembly contained in this organism may be a close approximation to the minimal set of genes required for bacterial growth. Here, we introduce a systematic approach for the construction and curation of a genome-scale in silico metabolic model for M. genitalium. Key challenges included estimation of biomass composition, handling of enzymes with broad specificities, and the lack of a defined medium. Computational tools were subsequently employed to identify and resolve connectivity gaps in the model as well as growth prediction inconsistencies with gene essentiality experimental data. The curated model, M. genitalium iPS189 (262 reactions, 274 metabolites), is 87% accurate in recapitulating in vivo gene essentiality results for M. genitalium. Approaches and tools described herein provide a roadmap for the automated construction of in silico metabolic models of other organisms. PMID:19214212

  3. MoMaS reactive transport benchmark using PFLOTRAN

    NASA Astrophysics Data System (ADS)

    Park, H.

    2017-12-01

    MoMaS benchmark was developed to enhance numerical simulation capability for reactive transport modeling in porous media. The benchmark was published in late September of 2009; it is not taken from a real chemical system, but realistic and numerically challenging tests. PFLOTRAN is a state-of-art massively parallel subsurface flow and reactive transport code that is being used in multiple nuclear waste repository projects at Sandia National Laboratories including Waste Isolation Pilot Plant and Used Fuel Disposition. MoMaS benchmark has three independent tests with easy, medium, and hard chemical complexity. This paper demonstrates how PFLOTRAN is applied to this benchmark exercise and shows results of the easy benchmark test case which includes mixing of aqueous components and surface complexation. Surface complexations consist of monodentate and bidentate reactions which introduces difficulty in defining selectivity coefficient if the reaction applies to a bulk reference volume. The selectivity coefficient becomes porosity dependent for bidentate reaction in heterogeneous porous media. The benchmark is solved by PFLOTRAN with minimal modification to address the issue and unit conversions were made properly to suit PFLOTRAN.

  4. Reduction of variance in spectral estimates for correction of ultrasonic aberration.

    PubMed

    Astheimer, Jeffrey P; Pilkington, Wayne C; Waag, Robert C

    2006-01-01

    A variance reduction factor is defined to describe the rate of convergence and accuracy of spectra estimated from overlapping ultrasonic scattering volumes when the scattering is from a spatially uncorrelated medium. Assuming that the individual volumes are localized by a spherically symmetric Gaussian window and that centers of the volumes are located on orbits of an icosahedral rotation group, the factor is minimized by adjusting the weight and radius of each orbit. Conditions necessary for the application of the variance reduction method, particularly for statistical estimation of aberration, are examined. The smallest possible value of the factor is found by allowing an unlimited number of centers constrained only to be within a ball rather than on icosahedral orbits. Computations using orbits formed by icosahedral vertices, face centers, and edge midpoints with a constraint radius limited to a small multiple of the Gaussian width show that a significant reduction of variance can be achieved from a small number of centers in the confined volume and that this reduction is nearly the maximum obtainable from an unlimited number of centers in the same volume.

  5. Study of power management technology for orbital multi-100KWe applications. Volume 2: Study results

    NASA Technical Reports Server (NTRS)

    Mildice, J. W.

    1980-01-01

    The preliminary requirements and technology advances required for cost effective space power management systems for multi-100 kilowatt requirements were identified. System requirements were defined by establishing a baseline space platform in the 250 KE KWe range and examining typical user loads and interfaces. The most critical design parameters identified for detailed analysis include: increased distribution voltages and space plasma losses, the choice between ac and dc distribution systems, shuttle servicing effects on reliability, life cycle costs, and frequency impacts to power management system and payload systems for AC transmission. The first choice for a power management system for this kind of application and size range is a hybrid ac/dc combination with the following major features: modular design and construction-sized minimum weight/life cycle cost; high voltage transmission (100 Vac RMS); medium voltage array or = 440 Vdc); resonant inversion; transformer rotary joint; high frequency power transmission line or = 20 KHz); energy storage on array side or rotary joint; fully redundant; and 10 year life with minimal replacement and repair.

  6. Design in Context: A Conceptual Framework for the Study of Computer Software in Higher Education.

    ERIC Educational Resources Information Center

    Kozma, Robert B.; Bangert-Drowns, Robert L.

    The conceptual groundwork needed to examine the impact of technology, primarily microcomputers, on student learning is presented. Medium, method, and context are tied with a science of design. In section I, research on technology in higher education is reviewed, medium and method are defined, and interaction with context is discussed. Taxonomies…

  7. Establishment of a Polychlorinated Biphenyl-Dechlorinating Microbial Consortium, Specific for Doubly Flanked Chlorines, in a Defined, Sediment-Free Medium

    PubMed Central

    Wu, Qingzhong; Sowers, Kevin R.; May, Harold D.

    2000-01-01

    Estuarine sediment from Charleston Harbor, South Carolina, was used as inoculum for the development of an anaerobic enrichment culture that specifically dechlorinates doubly flanked chlorines (i.e., chlorines bound to carbon that are flanked on both sides by other chlorine-carbon bonds) of polychlorinated biphenyls (PCBs). Dechlorination was restricted to the para chlorine in cultures enriched with 10 mM fumarate, 50 ppm (173 μM) 2,3,4,5-tetrachlorobiphenyl, and no sediment. Initially the rate of dechlorination decreased upon the removal of sediment from the medium. However, the dechlorinating activity was sustainable, and following sequential transfer in a defined, sediment-free estuarine medium, the activity increased to levels near that observed with sediment. The culture was nonmethanogenic, and molybdate, ampicillin, chloramphenicol, neomycin, and streptomycin inhibited dechlorination activity; bromoethanesulfonate and vancomycin did not. Addition of 17 PCB congeners indicated that the culture specifically removes double flanked chlorines, preferably in the para position, and does not attack ortho chlorines. This is the first microbial consortium shown to para or meta dechlorinate a PCB congener in a defined sediment-free medium. It is the second PCB-dechlorinating enrichment culture to be sustained in the absence of sediment, but its dechlorinating capabilities are entirely different from those of the other sediment-free PCB-dechlorinating culture, an ortho-dechlorinating consortium, and do not match any previously published Aroclor-dechlorinating patterns. PMID:10618202

  8. 16 CFR 1115.26 - Guidelines and policies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SUBSTANTIAL PRODUCT HAZARD REPORTS Guidelines and Requirements for Mandatory Recall Notices § 1115.26... minimize the use of highly technical or legal terminology. (3) A recall notice should be targeted and...; (ii) Computer, radio, television, or other electronic transmission or medium; (iii) Video news release...

  9. 16 CFR 1115.26 - Guidelines and policies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SUBSTANTIAL PRODUCT HAZARD REPORTS Guidelines and Requirements for Mandatory Recall Notices § 1115.26... minimize the use of highly technical or legal terminology. (3) A recall notice should be targeted and...; (ii) Computer, radio, television, or other electronic transmission or medium; (iii) Video news release...

  10. The TVT-obturator surgical procedure for the treatment of female stress urinary incontinence: a clinical update.

    PubMed

    Waltregny, David; de Leval, Jean

    2009-03-01

    Six years ago, the inside-out transobturator tape TVT-O procedure was developed for the surgical treatment of female stress urinary incontinence (SUI) with the aim of minimizing the risk of urethra and bladder injuries and ensuring minimal tissue dissection. Initial feasibility and efficacy studies suggested that the TVT-O procedure is associated with high SUI cure rates and low morbidity at short term. A recent analysis of medium-term results indicated that the TVT-O procedure is efficient, with maintenance, after a 3-year minimum follow-up, of cure rates comparing favorably with those reported for TVT. No late complications were observed. As of July 2008, more than 35 clinical papers, including ten randomized trials and two national registries, have been published on the outcome of the TVT-O surgery. Results from these studies have confirmed that the TVT-O procedure is safe and as efficient as the TVT procedure, at least in the short/medium term.

  11. N-Lauroylation during the Expression of Recombinant N-Myristoylated Proteins: Implications and Solutions.

    PubMed

    Flamm, Andrea Gabriele; Le Roux, Anabel-Lise; Mateos, Borja; Díaz-Lobo, Mireia; Storch, Barbara; Breuker, Kathrin; Konrat, Robert; Pons, Miquel; Coudevylle, Nicolas

    2016-01-01

    Incorporation of myristic acid onto the N terminus of a protein is a crucial modification that promotes membrane binding and correct localization of important components of signaling pathways. Recombinant expression of N-myristoylated proteins in Escherichia coli can be achieved by co-expressing yeast N-myristoyltransferase and supplementing the growth medium with myristic acid. However, undesired incorporation of the 12-carbon fatty acid lauric acid can also occur (leading to heterogeneous samples), especially when the available carbon sources are scarce, as it is the case in minimal medium for the expression of isotopically enriched samples. By applying this method to the brain acid soluble protein 1 and the 1-185 N-terminal region of c-Src, we show the significant, and protein-specific, differences in the membrane binding properties of lauroylated and myristoylated forms. We also present a robust strategy for obtaining lauryl-free samples of myristoylated proteins in both rich and minimal media. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  12. Formulation and Statistical Optimization of Culture Medium for Improved Production of Antimicrobial Compound by Streptomyces sp. JAJ06

    PubMed Central

    Arul Jose, Polpass; Sivakala, Kunjukrishnan Kamalakshi; Jebakumar, Solomon Robinson David

    2013-01-01

    Streptomyces sp. JAJ06 is a seawater-dependent antibiotic producer, previously isolated and characterised from an Indian coastal solar saltern. This paper reports replacement of seawater with a defined salt formulation in production medium and subsequent statistical media optimization to ensure consistent as well as improved antibiotic production by Streptomyces sp. JAJ06. This strain was observed to be proficient to produce antibiotic compound with incorporation of chemically defined sodium-chloride-based salt formulation instead of seawater into the production medium. Plackett-Burman design experiment was applied, and three media constituents, starch, KBr, and CaCO3, were recognised to have significant effect on the antibiotic production of Streptomyces JAJ06 at their individual levels. Subsequently, Response surface methodology with Box-Behnken design was employed to optimize these influencing medium constituents for the improved antibiotic production of Streptomyces sp. JAJ06. A total of 17 experiments were conducted towards the construction of a quadratic model and a second-order polynomial equation. Optimum levels of medium constituents were obtained by analysis of the model and numerical optimization method. When the strain JAJ06 was cultivated in the optimized medium, the antibiotic activity was increased to 173.3 U/mL, 26.8% increase as compared to the original (136.7 U/mL). This study found a useful way to cultivate Streptomyces sp. JAJ06 for enhanced production of antibiotic compound. PMID:24454383

  13. A primer on criticality safety

    DOE PAGES

    Costa, David A.; Cournoyer, Michael E.; Merhege, James F.; ...

    2017-05-01

    Criticality is the state of a nuclear chain reacting medium when the chain reaction is just self-sustaining (or critical). Criticality is dependent on nine interrelated parameters. Moreover, we design criticality safety controls in order to constrain these parameters to minimize fissions and maximize neutron leakage and absorption in other materials, which makes criticality more difficult or impossible to achieve. We present the consequences of criticality accidents are discussed, the nine interrelated parameters that combine to affect criticality are described, and criticality safety controls used to minimize the likelihood of a criticality accident are presented.

  14. Minimizing both dropped formulas and concepts in knowledge fusion

    NASA Astrophysics Data System (ADS)

    Grégoire, Éric

    2006-04-01

    In this paper, a new family of approaches to fuse inconsistent knowledge sources is introduced in a standard logical setting. They combine two preference criteria to arbitrate between conflicting information: the minimization of falsified formulas and the minimization of the number of the different atoms that are involved in those formulas. Although these criteria exhibit a syntactical flavor, the approaches are semantically-defined.

  15. Low-dose vaporized cannabis significantly improves neuropathic pain.

    PubMed

    Wilsey, Barth; Marcotte, Thomas; Deutsch, Reena; Gouaux, Ben; Sakai, Staci; Donaghe, Haylee

    2013-02-01

    We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling medium-dose (3.53%), low-dose (1.29%), or placebo cannabis with the primary outcome being visual analog scale pain intensity. Psychoactive side effects and neuropsychological performance were also evaluated. Mixed-effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the 2 active dose groups' results (P > .7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo versus low-dose, 2.9 for placebo versus medium-dose, and 25 for medium- versus low-dose. As these NNTs are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well tolerated, and neuropsychological effects were of limited duration and readily reversible within 1 to 2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain. The analgesia obtained from a low dose of delta-9-tetrahydrocannabinol (1.29%) in patients, most of whom were experiencing neuropathic pain despite conventional treatments, is a clinically significant outcome. In general, the effect sizes on cognitive testing were consistent with this minimal dose. As a result, one might not anticipate a significant impact on daily functioning. Published by Elsevier Inc.

  16. Evaluation of Contrail Reduction Strategies Based on Aircraft Flight Distances

    NASA Technical Reports Server (NTRS)

    Chen, Neil Y.; Sridhar, Banavar; Li, Jinhua; Ng, Hok Kwan

    2012-01-01

    This paper evaluates a set of contrail reduction strategies based on the flight range of aircraft as contrail reduction strategies have different impacts on aircraft depending on how they plan to fly. In general, aircraft with longer flight distances cruise at the altitudes where contrails are more likely to form. The concept of the contrail frequency index is used to quantify contrail impacts. The strategy for reducing the persistent contrail formation is to minimize the contrail frequency index by altering the aircraft's cruising altitude. A user-defined factor is used to trade off between contrail reduction and extra CO2 emissions. A higher value of tradeoff factor results in more contrail reduction and extra CO2 emissions. Results show that contrail reduction strategies using various tradeo factors behave differently from short-range flights to long-range ights. Analysis shows that short-distance flights (less than 500 miles) are the most frequent flights but contribute least to contrail reduction. Therefore these aircraft have the lowest priority when applying contrail reduction strategies. Medium-distance flights (500 to 1000 miles) have a higher priority if the goal is to achieve maximum contrail reduction in total; long-distance flights (1000 to 1500 miles) have a higher priority if the goal is to achieve maximum contrail reduction per flight. The characteristics of transcontinental flights (greater than 1500 miles) vary with different weather days so the priority of applying contrail reduction strategies to the group needs to be evaluated based on the locations of the contrail areas during any given day. For the days tested, medium-distance ights contribute up to 42.6% of the reduction among the groups during a day. The contrail frequency index per 1,000 miles for medium-distance, long-distance, and transcontinental flights can be reduced by an average of 75%. The results provide a starting point for developing operational policies to reduce the impact of aviation on climate based on aircraft flight distances.

  17. POLLUTION PREVENTION POSSIBILITIES FOR SMALL AND MEDIUM-SIZED INDUSTRIES: RESULTS OF THE WRITE PROJECTS

    EPA Science Inventory

    The Waste Reduction Innovative Technology Evaluation Program (WRITE) was a pilot program with six (6) states and one (1) local government, to identify priority needs at the respective governmental level, find promising waste minimization technologies and perform an evaluation to ...

  18. 16 CFR § 1115.26 - Guidelines and policies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REGULATIONS SUBSTANTIAL PRODUCT HAZARD REPORTS Guidelines and Requirements for Mandatory Recall Notices § 1115... minimize the use of highly technical or legal terminology. (3) A recall notice should be targeted and...; (ii) Computer, radio, television, or other electronic transmission or medium; (iii) Video news release...

  19. High Aflatoxin Production on a Chemically Defined Medium 1

    PubMed Central

    Reddy, T. V.; Viswanathan, L.; Venkitasubramanian, T. A.

    1971-01-01

    Aspergillus parasiticus ATCC 15517 produced 28 to 30 mg of aflatoxin per 100 ml of a medium containing sucrose, asparagine, and salts in stationary and shaken cultures. In the absence of asparagine in the medium, the toxin yields fell drastically, and the thin-layer chromatograms of the chloroform extracts of the cultures indicated the total absence of aflatoxin G1 and the presence of new intense blue and green fluorescent bands having RF values lower than aflatoxins. Initial pH was critical and had to be around 4.5 for good growth and high toxin production on this medium. Optimum concentrations of KH2PO4 and MgSO4·7H2O in the medium were much lower than those normally used in fungal growth media. PMID:5119206

  20. Continuous Culture of Ruminal Microorganisms in Chemically Defined Medium1

    PubMed Central

    Quinn, Loyd Y.; Burroughs, Wise; Christiansen, William C.

    1962-01-01

    Ruminal ciliates have been grown in continuous culture in chemically defined media and in the absence of viable bacteria. Oligotrichic ruminal ciliates seem to require insoluble carbohydrates for growth; the holotrichic ciliates require soluble carbohydrates, but at low concentrations. Both groups of ciliates utilize amino acids as their principal nitrogen source when these are supplied in micromolar concentrations; at millimolar concentrations, amino acids are toxic, possibly from excessive ammonia formation arising from ciliate deaminase activity. Holotrichic ruminal ciliates are destroyed by overdeposition of amylopectin when glucose is present above 0.1% concentration in the medium. Ecological requirements of ruminal ciliates are also described. Images FIG. 1 FIG. 2 PMID:13972780

  1. Determination of minimal clinically important change in early and advanced Parkinson's disease.

    PubMed

    Hauser, Robert A; Auinger, Peggy

    2011-04-01

    Two common primary efficacy outcome measures in Parkinson's disease (PD) are change in Unified Parkinson's Disease Rating Scale (UPDRS) scores in early PD and change in "off" time in patients with motor fluctuations. Defining the minimal clinically important change (MCIC) in these outcome measures is important to interpret the clinical relevance of changes observed in clinical trials and other situations. We analyzed data from 2 multicenter, placebo-controlled, randomized clinical trials of rasagiline; TEMPO studied 404 early PD subjects, and PRESTO studied 472 levodopa-treated subjects with motor fluctuations. An anchor-based approach using clinical global impression of improvement (CGI-I) was used to determine MCIC for UPDRS scores and daily "off" time. MCIC was defined as mean change in actively treated subjects rated minimally improved on CGI-I. Receiver operating characteristic (ROC) curves defined optimal cutoffs discriminating between changed and unchanged subjects. MCIC for improvement in total UPDRS score (parts I-III) in early PD was determined to be -3.5 points based on mean scores and -3.0 points based on ROC curves. In addition, we found an MCIC for reduction in "off" time of 1.0 hours as defined by mean reduction in "off" time in active treated subjects self-rated as minimally improved on CGI-I minus mean reduction in "off" time in placebo-treated subjects self-rated as unchanged (1.9-0.9 hours). We hypothesize that many methodological factors can influence determination of the MCIC, and a range of values is likely to emerge from multiple studies. Copyright © 2011 Movement Disorder Society.

  2. Glycerophosphate as a phosphorus source in a defined medium for Pichia pastoris fermentation.

    PubMed

    Zhang, Wenhui; Sinha, Jayanta; Meagher, Michael M

    2006-08-01

    Pichia pastoris has emerged as a commercially important yeast for the production of a vast majority of recombinant therapeutic proteins and vaccines. The organism can be grown to very high cell densities using a defined basal salts media (BSM). However, BSM contains bi-cation or tri-cation phosphate, which precipitates out of the medium at pH above 5.5, although the optimal fermentation pH of most recombinant protein fermentation varies between 5.5 and 7.0. In this article, the application of glycerophosphates was investigated as a substitute phosphate source in an effort to eliminate precipitation. The solubility of BSM containing sodium or potassium glycerophosphates was examined before and after autoclaving at various pHs. Sodium glycerophosphate was found stable at autoclave temperature but formed complexes with coexisting magnesium and calcium ions that were insoluble above pH 7.0. Medium where sodium glycerophosphate was autoclaved separately and then added to the growth medium did not produce any precipitate up to pH 10.5. The performance of P. pastoris fermentations expressing alpha-galactosidase and ovine interferon-tau using a glycerolphosphate-based medium was found to be comparable to a conventional BSM. The results from this work demonstrate that sodium glycerophosphate can be assimilated by the P. pastoris strains and can be employed as a reliable phosphorus source for both cell growth and recombinant protein production.

  3. Analysis of operational requirements for medium density air transportation. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The medium density air travel market was studied to determine the aircraft design and operational requirements. The impact of operational characteristics on the air travel system and the economic viability of the study aircraft were also evaluated. Medium density is defined in terms of numbers of people transported (20 to 500 passengers per day on round trip routes), and frequency of service ( a minumium of two and maximum of eight round trips per day) for 10 regional carriers. The operational characteristics of aircraft best suited to serve the medium density air transportation market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations could be conducted. The impact of selected aircraft on the medium density market, economics, and operations is ascertained. Research and technology objectives for future programs in medium density air transportation are identified and ranked.

  4. Denitration of 2,4,6-trinitrotoluene in aqueous solutions using small-molecular-weight catalyst(s) secreted by Pseudomonas aeruginosa ESA-5.

    PubMed

    Stenuit, Ben; Eyers, Laurent; Rozenberg, Raoul; Habib-Jiwan, Jean-Louis; Matthijs, Sandra; Cornelis, Pierre; Agathos, Spiros N

    2009-03-15

    The denitration of 2,4,6-trinitrotoluene (TNT) can produce mono- or dinitro aromatic compounds susceptible to microbial mineralization. In the present study, denitration of TNT and other nitro aromatic compounds was investigated with a solid-phase extract obtained from the culture supernatant of Pseudomonas aeruginosa ESA-5 grown on a chemically defined aerobic medium. When the C18 solid-phase extract containing extracellular catalysts (EC) was incubated with TNT and NAD(P)H, we observed a significant release of nitrite. The concentration of nitrite released in the reaction medium was strongly dependent on the concentration of NAD(P)H and EC. Denitration also occurred with two TNT-related molecules, 2,4,6-trinitrobenzaldehyde, and 2,4,6-trinitrobenzyl alcohol. The release of nitrite was coupled with the formation of two polar metabolites, and mass spectrometry analyses indicated that each of these compounds had lost two nitro groups from the trinitro aromatic parent molecule. During this process, the production of toxic reduced TNT metabolites was minimal. The incubation of EC with TNT, NAD(P)H, and specific scavengers of reactive oxygen species suggested the involvement of superoxide radicals (O2*-) and hydrogen peroxide in the denitration process. Results obtained in this study reveal for the first time that extracellular small-molecular-weight substance(s) of bacterial origin can serve as green catalyst(s) to initiate TNT denitration. In addition, this study gives clear evidence for the production of a TNT metabolite bearing a single nitro groupfollowing a denitration reaction with catalyst(s) of biotic origin.

  5. Accounting for patient size in the optimization of dose and image quality of pelvis cone beam CT protocols on the Varian OBI system.

    PubMed

    Wood, Tim J; Moore, Craig S; Horsfield, Carl J; Saunderson, John R; Beavis, Andrew W

    2015-01-01

    The purpose of this study was to develop size-based radiotherapy kilovoltage cone beam CT (CBCT) protocols for the pelvis. Image noise was measured in an elliptical phantom of varying size for a range of exposure factors. Based on a previously defined "small pelvis" reference patient and CBCT protocol, appropriate exposure factors for small, medium, large and extra-large patients were derived which approximate the image noise behaviour observed on a Philips CT scanner (Philips Medical Systems, Best, Netherlands) with automatic exposure control (AEC). Selection criteria, based on maximum tube current-time product per rotation selected during the radiotherapy treatment planning scan, were derived based on an audit of patient size. It has been demonstrated that 110 kVp yields acceptable image noise for reduced patient dose in pelvic CBCT scans of small, medium and large patients, when compared with manufacturer's default settings (125 kVp). Conversely, extra-large patients require increased exposure factors to give acceptable images. 57% of patients in the local population now receive much lower radiation doses, whereas 13% require higher doses (but now yield acceptable images). The implementation of size-based exposure protocols has significantly reduced radiation dose to the majority of patients with no negative impact on image quality. Increased doses are required on the largest patients to give adequate image quality. The development of size-based CBCT protocols that use the planning CT scan (with AEC) to determine which protocol is appropriate ensures adequate image quality whilst minimizing patient radiation dose.

  6. Algal growth response to particle-bound orthophosphate and zinc.

    USGS Publications Warehouse

    Kuwabara, J.S.; Davis, J.A.; Chang, Cecily C.Y.

    1986-01-01

    Effects of Zn (0-1 mu M total Zn(II)) and orthophosphate (8-12 mu M total P) additions on growth indices for the chlorophyte Selenastrum capricornutum were examined in a medium containing 50 mg liter-1 colloidal titania. Over the Zn(II) concentration range used, detrimental growth and yield effects were observed. Addition of P to a synthetic growth medium increased stationary phase cell density, but had minimal effect on growth rate and duration of lag phase. Presence of TiO2 particles in culture media significantly reduced Zn and P dissolved fractions.-from Authors

  7. Production of High-Viscosity Whey Broths by a Lactose-Utilizing Xanthomonas campestris Strain

    PubMed Central

    Schwartz, Robert D.; Bodie, Elizabeth A.

    1985-01-01

    Xanthomonas campestris BB-1L was isolated by enrichment and selection by serial passage in a lactose-minimal medium. When BB-1L was subsequently grown in medium containing only 4% whey and 0.05% yeast extract, the lactose was consumed and broth viscosities greater than 500 cps at a 12 s−1 shear rate were produced. Prolonged maintenance in whey resulted in the loss of the ability of BB-1L to produce viscous broths in whey, indicating a reversion to preferential growth on whey protein, like the parent strain. PMID:16346946

  8. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A NUCLEAR POWERED ELECTRICAL GENERATING STATION.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  9. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF COMMERCIAL REFRIGERATION UNITS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  10. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF COMMERCIAL REFRIGERATION UNITS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of the...

  11. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ARTISTS' SUPPLY PAINTS.

    EPA Science Inventory

    The Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of the sites...

  12. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ELECTROPLATING CHEMICAL PRODUCTS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  13. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A SCRAP METAL RECOVERY FACILITY.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of the...

  14. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ORTHOPEDIC IMPLANTS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  15. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ORTHOPEDIC IMPLANTS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  16. Method of producing purified carotenoid compounds

    NASA Technical Reports Server (NTRS)

    Eggink, Laura (Inventor)

    2007-01-01

    A method of producing a carotenoid in solid form includes culturing a strain of Chlorophyta algae cells in a minimal inorganic medium and separating the algae comprising a solid form of carotenoid. In one embodiment f the invention, the strain of Chlorophyta algae cells includes a strain f Chlamydomonas algae cells.

  17. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A REMANUFACTURER OF AUTOMOBILE RADIATORS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  18. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A REMANUFACTURER OF AUTOMOBILE RADIATORS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  19. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A STATE DEPARTMENT OF TRANSPORTATION.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the State of New Jersey. One of th...

  20. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF WRITING INSTRUMENTS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  1. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR AN AUTOBODY REPAIR FACILITY.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of the...

  2. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF HARDENED STEEL GEARS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of the...

  3. High-Aspect-Ratio Rotating Cell-Culture Vessel

    NASA Technical Reports Server (NTRS)

    Wolf, David A.; Sams, Clarence; Schwarz, Ray P.

    1992-01-01

    Cylindrical rotating cell-culture vessel with thin culture-medium layer of large surface area provides exchange of nutrients and products of metabolism with minimal agitation. Rotation causes averaging of buoyant forces otherwise separating components of different densities. Vessel enables growth of cells in homogeneous distribution with little agitation and little shear stress.

  4. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF FINISHED LEATHER.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  5. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ELECTROPLATED WIRE.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of the...

  6. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A NUCLEAR POWERED ELECTRICAL GENERATING STATION

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  7. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A TRANSPORTER OF BULK PLASTIC PELLETS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  8. Exploring the cost-utility of stratified primary care management for low back pain compared with current best practice within risk-defined subgroups.

    PubMed

    Whitehurst, David G T; Bryan, Stirling; Lewis, Martyn; Hill, Jonathan; Hay, Elaine M

    2012-11-01

    Stratified management for low back pain according to patients' prognosis and matched care pathways has been shown to be an effective treatment approach in primary care. The aim of this within-trial study was to determine the economic implications of providing such an intervention, compared with non-stratified current best practice, within specific risk-defined subgroups (low-risk, medium-risk and high-risk). Within a cost-utility framework, the base-case analysis estimated the incremental healthcare cost per additional quality-adjusted life year (QALY), using the EQ-5D to generate QALYs, for each risk-defined subgroup. Uncertainty was explored with cost-utility planes and acceptability curves. Sensitivity analyses were performed to consider alternative costing methodologies, including the assessment of societal loss relating to work absence and the incorporation of generic (ie, non-back pain) healthcare utilisation. The stratified management approach was a cost-effective treatment strategy compared with current best practice within each risk-defined subgroup, exhibiting dominance (greater benefit and lower costs) for medium-risk patients and acceptable incremental cost to utility ratios for low-risk and high-risk patients. The likelihood that stratified care provides a cost-effective use of resources exceeds 90% at willingness-to-pay thresholds of £4000 (≈ 4500; $6500) per additional QALY for the medium-risk and high-risk groups. Patients receiving stratified care also reported fewer back pain-related days off work in all three subgroups. Compared with current best practice, stratified primary care management for low back pain provides a highly cost-effective use of resources across all risk-defined subgroups.

  9. Relationship between pH and Medium Dissolved Solids in Terms of Growth and Metabolism of Lactobacilli and Saccharomyces cerevisiae during Ethanol Production

    PubMed Central

    Narendranath, Neelakantam V.; Power, Ronan

    2005-01-01

    The specific growth rates of four species of lactobacilli decreased linearly with increases in the concentration of dissolved solids (sugars) in liquid growth medium. This was most likely due to the osmotic stress exerted by the sugars on the bacteria. The reduction in growth rates corresponded to decreased lactic acid production. Medium pH was another factor studied. As the medium pH decreased from 5.5 to 4.0, there was a reduction in the specific growth rate of lactobacilli and a corresponding decrease in the lactic acid produced. In contrast, medium pH did not have any significant effect on the specific growth rate of yeast at any particular concentration of dissolved solids in the medium. However, medium pH had a significant (P < 0.001) effect on ethanol production. A medium pH of 5.5 resulted in maximal ethanol production in all media with different concentrations of dissolved solids. When the data were analyzed as a 4 (pH levels) by 4 (concentrations of dissolved solids) factorial experiment, there was no synergistic effect (P > 0.2923) observed between pH of the medium and concentration of dissolved solids of the medium in reducing bacterial growth and metabolism. The data suggest that reduction of initial medium pH to 4.0 for the control of lactobacilli during ethanol production is not a good practice as there is a reduction (P < 0.001) in the ethanol produced by the yeast at pH 4.0. Setting the mash (medium) with ≥30% (wt/vol) dissolved solids at a pH of 5.0 to 5.5 will minimize the effects of bacterial contamination and maximize ethanol production by yeast. PMID:15870306

  10. The regulation of progesterone receptor by 17 beta estradiol and tamoxifen in the Zr-75-1 human breast cancer cell line in defined medium.

    PubMed

    Allegra, J C; Korat, O; Do, H M; Lippman, M

    1981-01-01

    The regulation of progesterone receptor by 17 beta estradiol and tamoxifen in the ZR-75-1 human breast cancer cell line in defined medium is described. ZR-75-1 cells maintained in serum free hormone supplemented medium minus estradiol lack progesterone receptor activity. Readdition of estradiol to these cells leads to a marked stimulation of progesterone receptor activity (0 to greater than 100 fmols of specifically bound progesterone per million cells). Tamoxifen (10(-6)M-10(-8)M) does not stimulate progesterone receptor activity in this cell line. The presence of progesterone receptor activity is not directly related to growth. Withdrawal of insulin in the continued presence of estradiol has no effect on progesterone receptor concentration although net cell growth ceases. Conversely, withdrawal of estradiol in the continued presence of insulin induces a cessation of net cell growth accompanied by a loss of all progesterone receptor activity within 3-5 days.

  11. Coal char oxidation kinetics in air medium

    NASA Astrophysics Data System (ADS)

    Slyusarskiy, K. V.; Jankovskiy, S. A.; Korotkikh, A. G.; Sorokin, I. V.

    2017-01-01

    Research on oxidation in air medium process of three different coal chars with various carbon content was presented. The anthracite, T-grade bituminous coal and 2B-grade lignite char powders with particle size less than 80 µm were studied. The coal char oxidation was studied by isothermal method using coupled TG-DSC analyzer Netzsch STA 449 Jupiter F3 in the temperature range 1000-1200 °C. Experiments were carried out at ambient pressure. Volumetric flow rate of oxidation medium into analyzer chamber was 250 ml/min and consisted of oxygen and argon with volumetric ratio 24:1. Based on experimental data, the average rate of carbon oxidation reaction values were defined at each temperature. Kinetic constants (frequency factor and activation energy) of reaction were defined as well via 1st order Arrhenius equation. Activation energy values are in good agreement with the data presented in the literature. Activation energy values for anthracite char are 1.6-1.7 times higher than those for bituminous coal and lignite chars, respectively.

  12. Combined genetic transformation and nutritional assay for identification of Moraxella nonliquefaciens.

    PubMed Central

    Juni, E; Heym, G A; Maurer, M J; Miller, M L

    1987-01-01

    A combined genetic transformation and nutritional assay is described that permits definitive identification of clinically isolated strains of Moraxella nonliquefaciens. Crude DNA preparations of strains of various Moraxella species were used to transform nutritional mutants of a stably competent strain of M. nonliquefaciens for ability to grow on a defined medium (Mn-B). DNA samples from 24 independently isolated strains of M. nonliquefaciens all resulted in massive (4+) transformation of each of two mutant assay strains. DNA samples from strains of M. bovis and M. lacunata frequently gave weak (1+) transformation of one of the mutant assay strains (Mn64) but almost always failed to transform another assay strain (Mn136). DNA samples from eight other Moraxella species failed completely to transform either of the mutant assay strains. When streaked on the defined medium used for the transformation assay (Mn-B), 23 of the 24 strains of M. nonliquefaciens grew well, but all strains of M. bovis and M. lacunata failed to grow on this medium. Images PMID:3654942

  13. Forces exerted by a correlated fluid on embedded inclusions.

    PubMed

    Bitbol, Anne-Florence; Fournier, Jean-Baptiste

    2011-06-01

    We investigate the forces exerted on embedded inclusions by a fluid medium with long-range correlations, described by an effective scalar field theory. Such forces are the basis for the medium-mediated Casimir-like force. To study these forces beyond thermal average, it is necessary to define them in each microstate of the medium. Two different definitions of these forces are currently used in the literature. We study the assumptions underlying them. We show that only the definition that uses the stress tensor of the medium gives the sought-after force exerted by the medium on an embedded inclusion. If a second inclusion is embedded in the medium, the thermal average of this force gives the usual Casimir-like force between the two inclusions. The other definition can be used in the different physical case of an object that interacts with the medium without being embedded in it. We show in a simple example that the two definitions yield different results for the variance of the Casimir-like force.

  14. Establishment of a Brazilian line of human embryonic stem cells in defined medium: implications for cell therapy in an ethnically diverse population.

    PubMed

    Fraga, Ana M; Sukoyan, Marina; Rajan, Prithi; Braga, Daniela Paes de Almeida Ferreira; Iaconelli, Assumpto; Franco, José Gonçalves; Borges, Edson; Pereira, Lygia V

    2011-01-01

    Pluripotent human embryonic stem (hES) cells are an important experimental tool for basic and applied research, and a potential source of different tissues for transplantation. However, one important challenge for the clinical use of these cells is the issue of immunocompatibility, which may be dealt with by the establishment of hES cell banks to attend different populations. Here we describe the derivation and characterization of a line of hES cells from the Brazilian population, named BR-1, in commercial defined medium. In contrast to the other hES cell lines established in defined medium, BR-1 maintained a stable normal karyotype as determined by genomic array analysis after 6 months in continuous culture (passage 29). To our knowledge, this is the first reported line of hES cells derived in South America. We have determined its genomic ancestry and compared the HLA-profile of BR-1 and another 22 hES cell lines established elsewhere with those of the Brazilian population, finding they would match only 0.011% of those individuals. Our results highlight the challenges involved in hES cell banking for populations with a high degree of ethnic admixture.

  15. Statistical optimization of culture conditions for the production of enniatins H, I, and MK1688 by Fusarium oxysporum KFCC 11363P.

    PubMed

    Lee, Hee-Seok; Kang, Jea-Wook; Kim, Byung Hee; Park, Sang-Gyu; Lee, Chan

    2011-03-01

    The aim of this study was to optimize the culture conditions for the production of biological cyclic hexadepsipeptides (enniatins H, I and MK1688) from Fusarium oxysporum KFCC 11363P. Tests of 10 complete or chemically defined liquid culture media revealed that Fusarium defined medium was the best for the production of enniatins (produced amounts: enniatin H, 185.4 mg/L; enniatin I, 349.1mg/L; enniatin MK1688, 541.1mg/L; and total enniatins, 1075.6 mg/L). On the eighth day after inoculation, the maximal production of enniatins was observed at 25°C in Fusarium defined medium. The optimal carbon and nitrogen sources for producing biological cyclic hexadepsipeptides (enniatins H, I, and MK1688) were sucrose and NaNO(3), respectively, and their optimal concentrations were determined by the principle of response surface methodology. It was confirmed that using the optimized growth medium compositions increased the amounts of enniatins H, I, and MK1688, and total enniatins produced to 695.2, 882.4, 824.8, and 2398.5mg/L, respectively. These findings will assist in formulating microbiological media useful for enniatin research. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  16. Generation of hematopoietic stem cells from human embryonic stem cells using a defined, stepwise, serum-free, and serum replacement-free monolayer culture method.

    PubMed

    Kim, So-Jung; Jung, Ji-Won; Ha, Hye-Yeong; Koo, Soo Kyung; Kim, Eung-Gook; Kim, Jung-Hyun

    2017-03-01

    Embryonic stem cells (ESCs) can be expanded infinitely in vitro and have the potential to differentiate into hematopoietic stem cells (HSCs); thus, they are considered a useful source of cells for HSC production. Although several technical in vitro methods for engineering HSCs from pluripotent stem cells have been developed, clinical application of HSCs engineered from pluripotent stem cells is restricted because of the possibility of xenogeneic contamination resulting from the use of murine materials. Human ESCs (CHA-hES15) were cultured on growth factor-reduced Matrigel-coated dishes in the mTeSR1 serum-free medium. When the cells were 70% confluent, we initiated HSC differentiation by three methods involving (1) knockout serum replacement (KSR), cytokines, TGFb1, EPO, and FLT3L; (2) KSR, cytokines, and bFGF; or (3) cytokines and bFGF. Among the three differentiation methods, the minimal number of cytokines without KSR resulted in the greatest production of HSCs. The optimized method resulted in a higher proportion of CD34 + CD43 + hematopoietic progenitor cells (HPCs) and CD34 + CD45 + HPCs compared to the other methods. In addition, the HSCs showed the potential to differentiate into multiple lineages of hematopoietic cells in vitro . In this study, we optimized a two-step, serum-free, animal protein-free, KSR-free, feeder-free, chemically defined monolayer culture method for generation of HSCs and hematopoietic stem and progenitor cells (HSPCs) from human ESCs.

  17. Optimization of a chondrogenic medium through the use of factorial design of experiments.

    PubMed

    Enochson, Lars; Brittberg, Mats; Lindahl, Anders

    2012-12-01

    The standard culture system for in vitro cartilage research is based on cells in a three-dimensional micromass culture and a defined medium containing the chondrogenic key growth factor, transforming growth factor (TGF)-β1. The aim of this study was to optimize the medium for chondrocyte micromass culture. Human chondrocytes were cultured in different media formulations, designed with a factorial design of experiments (DoE) approach and based on the standard medium for redifferentiation. The significant factors for the redifferentiation of the chondrocytes were determined and optimized in a two-step process through the use of response surface methodology. TGF-β1, dexamethasone, and glucose were significant factors for differentiating the chondrocytes. Compared to the standard medium, TGF-β1 was increased 30%, dexamethasone reduced 50%, and glucose increased 22%. The potency of the optimized medium was validated in a comparative study against the standard medium. The optimized medium resulted in micromass cultures with increased expression of genes important for the articular chondrocyte phenotype and in cultures with increased glycosaminoglycan/DNA content. Optimizing the standard medium with the efficient DoE method, a new medium that gave better redifferentiation for articular chondrocytes was determined.

  18. Fiber optic assembly and method of making same

    DOEpatents

    Kramer, D.P.; Beckman, T.M.

    1997-09-02

    There is provided an assembly having a light guiding medium sealed to a holder. Preferably the holder is a metal shell and a light guiding medium is an optical fiber of glass or sapphire whisker. The assembly includes a sealing medium which sealingly engages the metal holder to the fiber. In the formation of the assembly, the seal is essentially hermetic having a capability of minimizing leakage having a helium leak rate of less than 1{times}10{sup {minus}8} cubic centimeters per second and high strength having a capability of withstanding pressures of 100,000 psi or greater. The features of the assembly are obtained by a specific preparation method and by selection of specific starting materials. The fiber is selected to have a sufficiently high coefficient of thermal expansion which minimizes strains in the component during fabrication, as a result of fabrication, and during use. The other components are selected to be of a material having compatible coefficients of thermal expansion (TEC) where the TEC of the holder is greater than or equal to the TEC of the sealing material. The TEC of the sealing material is in turn greater than or equal to the TEC of the fiber. It is preferred that the materials be selected so that their respective coefficients of thermal expansion are as close as possible to one another and they may all be equal. 4 figs.

  19. Fiber optic assembly and method of making same

    DOEpatents

    Kramer, Daniel P.; Beckman, Thomas M.

    1997-09-02

    There is provided an assembly having a light guiding medium sealed to a her. Preferably the holder is a metal shell and a light guiding medium is an optical fiber of glass or sapphire whisker. The assembly includes a sealing medium which sealingly engages the metal holder to the fiber. In the formation of the assembly, the seal is essentially hermetic having a capability of minimizing leakage having a helium leak rate of less than 1.times.10.sup.-8 cubic centimeters per second and high strength having a capability of withstanding pressures of 100,000 psi or greater. The features of the assembly are obtained by a specific preparation method and by selection of specific starting materials. The fiber is selected to have a sufficiently high coefficient of thermal expansion which minimizes strains in the component during fabrication, as a result of fabrication, and during use. The other components are selected to be of a material having compatible coefficients of thermal expansion (TEC) where the TEC of the holder is greater than or equal to the TEC of the sealing material. The TEC of the sealing material is in turn greater than or equal to the TEC of the fiber. It is preferred that the materials be selected so that their respective coefficients of thermal expansion are as close as possible to one another and they may all be equal.

  20. An alternative method for the analysis of melanin production in Cryptococcus neoformans sensu lato and Cryptococcus gattii sensu lato.

    PubMed

    Brilhante, Raimunda S N; España, Jaime D A; de Alencar, Lucas P; Pereira, Vandbergue S; Castelo-Branco, Débora de S C M; Pereira-Neto, Waldemiro de A; Cordeiro, Rossana de A; Sidrim, José J C; Rocha, Marcos F G

    2017-10-01

    Melanin is an important virulence factor for several microorganisms, including Cryptococcus neoformans sensu lato and Cryptococcus gattii sensu lato, thus, the assessment of melanin production and its quantification may contribute to the understanding of microbial pathogenesis. The objective of this study was to standardise an alternative method for the production and indirect quantification of melanin in C. neoformans sensu lato and C. gattii sensu lato. Eight C. neoformans sensu lato and three C. gattii sensu lato, identified through URA5 methodology, Candida parapsilosis ATCC 22019 (negative control) and one Hortaea werneckii (positive control) were inoculated on minimal medium agar with or without L-DOPA, in duplicate, and incubated at 35°C, for 7 days. Pictures were taken from the third to the seventh day, under standardised conditions in a photographic chamber. Then, photographs were analysed using grayscale images. All Cryptococcus spp. strains produced melanin after growth on minimal medium agar containing L-DOPA. C. parapsilosis ATCC 22019 did not produce melanin on medium containing L-DOPA, while H. werneckii presented the strongest pigmentation. This new method allows the indirect analysis of melanin production through pixel quantification in grayscale images, enabling the study of substances that can modulate melanin production. © 2017 Blackwell Verlag GmbH.

  1. How accurate is our clinical prediction of "minimal prostate cancer"?

    PubMed

    Leibovici, Dan; Shikanov, Sergey; Gofrit, Ofer N; Zagaja, Gregory P; Shilo, Yaniv; Shalhav, Arieh L

    2013-07-01

    Recommendations for active surveillance versus immediate treatment for low risk prostate cancer are based on biopsy and clinical data, assuming that a low volume of well-differentiated carcinoma will be associated with a low progression risk. However, the accuracy of clinical prediction of minimal prostate cancer (MPC) is unclear. To define preoperative predictors for MPC in prostatectomy specimens and to examine the accuracy of such prediction. Data collected on 1526 consecutive radical prostatectomy patients operated in a single center between 2003 and 2008 included: age, body mass index, preoperative prostate-specific antigen level, biopsy Gleason score, clinical stage, percentage of positive biopsy cores, and maximal core length (MCL) involvement. MPC was defined as < 5% of prostate volume involvement with organ-confined Gleason score < or = 6. Univariate and multivariate logistic regression analyses were used to define independent predictors of minimal disease. Classification and Regression Tree (CART) analysis was used to define cutoff values for the predictors and measure the accuracy of prediction. MPC was found in 241 patients (15.8%). Clinical stage, biopsy Gleason's score, percent of positive biopsy cores, and maximal involved core length were associated with minimal disease (OR 0.42, 0.1, 0.92, and 0.9, respectively). Independent predictors of MPC included: biopsy Gleason score, percent of positive cores and MCL (OR 0.21, 095 and 0.95, respectively). CART showed that when the MCL exceeded 11.5%, the likelihood of MPC was 3.8%. Conversely, when applying the most favorable preoperative conditions (Gleason < or = 6, < 20% positive cores, MCL < or = 11.5%) the chance of minimal disease was 41%. Biopsy Gleason score, the percent of positive cores and MCL are independently associated with MPC. While preoperative prediction of significant prostate cancer was accurate, clinical prediction of MPC was incorrect 59% of the time. Caution is necessary when implementing clinical data as selection criteria for active surveillance.

  2. Minimal measures for Euler-Lagrange flows on finite covering spaces

    NASA Astrophysics Data System (ADS)

    Wang, Fang; Xia, Zhihong

    2016-12-01

    In this paper we study the minimal measures for positive definite Lagrangian systems on compact manifolds. We are particularly interested in manifolds with more complicated fundamental groups. Mather’s theory classifies the minimal or action-minimizing measures according to the first (co-)homology group of a given manifold. We extend Mather’s notion of minimal measures to a larger class for compact manifolds with non-commutative fundamental groups, and use finite coverings to study the structure of these extended minimal measures. We also define action-minimizers and minimal measures in the homotopical sense. Our program is to study the structure of homotopical minimal measures by considering Mather’s minimal measures on finite covering spaces. Our goal is to show that, in general, manifolds with a non-commutative fundamental group have a richer set of minimal measures, hence a richer dynamical structure. As an example, we study the geodesic flow on surfaces of higher genus. Indeed, by going to the finite covering spaces, the set of minimal measures is much larger and more interesting.

  3. Relation of perioperative deaths to hospital volume among patients undergoing pancreatic resection for malignancy.

    PubMed Central

    Lieberman, M D; Kilburn, H; Lindsey, M; Brennan, M F

    1995-01-01

    OBJECTIVE: The authors examined the effect of hospital and surgeon volume on perioperative mortality rates after pancreatic resection for the treatment of pancreatic cancer. METHODS: Discharge abstracts from 1972 patients who had undergone pancreaticoduodenectomy or total pancreatectomy for malignancy in New York State between 1984 and 1991 were obtained from the Statewide Planning and Research Cooperative System. Logistic regression analysis was used to determine the relationship between hospital and surgeon experience to perioperative outcome. RESULTS: More than 75% of patients underwent resection at minimal-volume (fewer than 10 cases) or low-volume (10-50 cases) centers (defined as hospitals in which a minimal number of resections were performed in a given year), and these hospitals represented 98% of the institutions treating peripancreatic cancer. The two high-volume hospitals (more than 81 cases) demonstrated a significantly lower perioperative mortality rate (4.0%) compared with the minimal- (21.8%) and low-volume (12.3%) hospitals (p < 0.001). The perioperative mortality rate was 15.5% for low-volume (fewer than 9 cases) surgeons (defined as surgeons who had performed a minimal number of resections in any hospital in a given year) (n = 687) compared with 4.7% for high-volume (more than 41 cases) pancreatic surgeons (n = 4) (p < 0.001). Logistic regression analysis demonstrated that perioperative death is significantly (p < 0.05) related to hospital volume, but the surgeon's experience is not significantly related to perioperative deaths when hospital volume is controlled. CONCLUSIONS: These data support a defined minimum hospital experience for elective pancreatectomy for malignancy to minimize perioperative deaths. PMID:7487211

  4. DNASynth: a software application to optimization of artificial gene synthesis

    NASA Astrophysics Data System (ADS)

    Muczyński, Jan; Nowak, Robert M.

    2017-08-01

    DNASynth is a client-server software application in which the client runs in a web browser. The aim of this program is to support and optimize process of artificial gene synthesizing using Ligase Chain Reaction. Thanks to LCR it is possible to obtain DNA strand coding defined by user peptide. The DNA sequence is calculated by optimization algorithm that consider optimal codon usage, minimal energy of secondary structures and minimal number of required LCR. Additionally absence of sequences characteristic for defined by user set of restriction enzymes is guaranteed. The presented software was tested on synthetic and real data.

  5. Heavy metal toxicity to bacteria - are the existing growth media accurate enough to determine heavy metal toxicity?

    PubMed

    Rathnayake, I V N; Megharaj, Mallavarapu; Krishnamurti, G S R; Bolan, Nanthi S; Naidu, Ravi

    2013-01-01

    A new minimal medium was formulated considering the limitations of the existing media for testing heavy metal sensitivity to bacteria. Toxicity of cadmium and copper to three bacteria was investigated in the new medium and compared with three other media commonly used to study the effect of the toxic metals. Based on speciation data arrived at using ion-selective electrodes, the available free-metal concentration in solution was highest in the MES-buffered medium. This finding was strongly supported by the estimated EC(50) values for the metals tested based on the toxicity bioassays. The free-ionic cadmium and copper concentrations in the medium provide more accurate determination of metal concentrations that affects the bacteria, than with most of other existing media. This will avoid doubts on other media and misleading conclusions relevant to the toxicity of heavy metals to bacteria and provides a better option for the study of metal-bacteria interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Finding Space for Non-Dominant Languages in Education: Language Policy and Medium of Instruction in Timor-Leste 2000-2012

    ERIC Educational Resources Information Center

    Taylor-Leech, Kerry

    2013-01-01

    Timor-Leste offers a rich case study of the array of discursive influences on medium-of-instruction (MOI) policy in multilingual, post-colonial developing contexts. MOI policy in this young nation is a site of tension between struggles to define national identity in the shadow of colonial language ideologies and the globalised discourses of…

  7. Chemical Growth Regulators for Guayule Plants

    NASA Technical Reports Server (NTRS)

    Dastoor, M. N.; Schubert, W. W.; Petersen, G. R.

    1982-01-01

    Test Tubes containing Guayule - tissue cultures were used in experiments to test effects of chemical-growth regulators. The shoots grew in response to addition of 2-(3,4-dichlorophenoxy)-triethylamine (triethylamine (TEA) derivative) to agar medium. Preliminary results indicate that a class of compounds that promotes growth in soil may also promote growth in a culture medium. Further experiments are needed to define the effect of the TEA derivative.

  8. Bipolar plate/diffuser for a proton exchange membrane fuel cell

    DOEpatents

    Besmann, Theodore M.; Burchell, Timothy D.

    2001-01-01

    A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

  9. Bipolar plate/diffuser for a proton exchange membrane fuel cell

    DOEpatents

    Besmann, Theodore M.; Burchell, Timothy D.

    2000-01-01

    A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

  10. Gap-minimal systems of notations and the constructible hierarchy

    NASA Technical Reports Server (NTRS)

    Lucian, M. L.

    1972-01-01

    If a constructibly countable ordinal alpha is a gap ordinal, then the order type of the set of index ordinals smaller than alpha is exactly alpha. The gap ordinals are the only points of discontinuity of a certain ordinal-valued function. The notion of gap minimality for well ordered systems of notations is defined, and the existence of gap-minimal systems of notations of arbitrarily large constructibly countable length is established.

  11. Minimally Invasive Mitral Valve Surgery III

    PubMed Central

    Lehr, Eric J.; Guy, T. Sloane; Smith, Robert L.; Grossi, Eugene A.; Shemin, Richard J.; Rodriguez, Evelio; Ailawadi, Gorav; Agnihotri, Arvind K.; Fayers, Trevor M.; Hargrove, W. Clark; Hummel, Brian W.; Khan, Junaid H.; Malaisrie, S. Chris; Mehall, John R.; Murphy, Douglas A.; Ryan, William H.; Salemi, Arash; Segurola, Romualdo J.; Smith, J. Michael; Wolfe, J. Alan; Weldner, Paul W.; Barnhart, Glenn R.; Goldman, Scott M.; Lewis, Clifton T. P.

    2016-01-01

    Abstract Minimally invasive mitral valve operations are increasingly common in the United States, but robotic-assisted approaches have not been widely adopted for a variety of reasons. This expert opinion reviews the state of the art and defines best practices, training, and techniques for developing a successful robotics program. PMID:27662478

  12. POLLUTION BALANCE: A NEW METHODOLOGY FOR MINIMIZING WASTE PRODUCTION IN MANUFACTURING PROCESSES.

    EPA Science Inventory

    A new methodolgy based on a generic pollution balance equation, has been developed for minimizing waste production in manufacturing processes. A "pollution index," defined as the mass of waste produced per unit mass of a product, has been introduced to provide a quantitative meas...

  13. Storage Optimization of Educational System Data

    ERIC Educational Resources Information Center

    Boja, Catalin

    2006-01-01

    There are described methods used to minimize data files dimension. There are defined indicators for measuring size of files and databases. The storage optimization process is based on selecting from a multitude of data storage models the one that satisfies the propose problem objective, maximization or minimization of the optimum criterion that is…

  14. A Defense of Semantic Minimalism

    ERIC Educational Resources Information Center

    Kim, Su

    2012-01-01

    Semantic Minimalism is a position about the semantic content of declarative sentences, i.e., the content that is determined entirely by syntax. It is defined by the following two points: "Point 1": The semantic content is a complete/truth-conditional proposition. "Point 2": The semantic content is useful to a theory of…

  15. Nuclear and mitochondrial DNA in blastocoele fluid and embryo culture medium: evidence and potential clinical use.

    PubMed

    Hammond, Elizabeth R; Shelling, Andrew N; Cree, Lynsey M

    2016-08-01

    The ability to screen embryos for aneuploidy or inherited disorders in a minimally invasive manner may represent a major advancement for the future of embryo viability assessment. Recent studies have demonstrated that both blastocoele fluid and embryo culture medium contain genetic material, which can be isolated and subjected to downstream genetic analysis. The blastocoele fluid may represent an alternative source of nuclear DNA for aneuploidy testing, although the degree to which the isolated genetic material is solely representative of the developing embryo is currently unclear. In addition to nuclear DNA, mitochondrial DNA (mtDNA) can be detected in the embryo culture medium. Currently, the origin of this nuclear and mtDNA has not been fully evaluated and there are several potential sources of contamination that may contribute to the genetic material detected in the culture medium. There is however evidence that the mtDNA content of the culture medium is related to embryo fragmentation levels and its presence is predictive of blastulation, indicating that embryo development may influence the levels of genetic material detected. If the levels of genetic material are strongly related to aspects of embryo quality, then this may be a novel biomarker of embryo viability. If the genetic material does have an embryo origin, the mechanisms by which DNA may be released into the blastocoele fluid and embryo culture medium are unknown, although apoptosis may play a role. While the presence of this genetic material is an exciting discovery, the DNA in the blastocoele fluid and embryo culture medium appears to be of low yield and integrity, which makes it challenging to study. Further research aimed at assessing the methodologies used for both isolating and analysing this genetic material, as well as tracing its origin, are needed in order to evaluate its potential for clinical use. Should such methodologies prove to be routinely successful and the DNA recovered demonstrated to be embryonic in origin, then they may be used in a minimally invasive and less technical methodology for genetic analysis and embryo viability assessment than those currently available. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Development of a chemically defined platform fed-batch culture media for monoclonal antibody-producing CHO cell lines with optimized choline content.

    PubMed

    Kuwae, Shinobu; Miyakawa, Ichiko; Doi, Tomohiro

    2018-01-11

    A chemically defined platform basal medium and feed media were developed using a single Chinese hamster ovary (CHO) cell line that produces a monoclonal antibody (mAb). Cell line A, which showed a peak viable cell density of 5.9 × 10 6  cells/mL and a final mAb titer of 0.5 g/L in batch culture, was selected for the platform media development. Stoichiometrically balanced feed media were developed using glucose as an indicator of cell metabolism to determine the feed rates of all other nutrients. A fed-batch culture of cell line A using the platform fed-batch medium yielded a 6.4 g/L mAb titer, which was 12-fold higher than that of the batch culture. To examine the applicability of the platform basal medium and feed media, three other cell lines (A16, B, and C) that produce mAbs were cultured using the platform fed-batch medium, and they yielded mAb titers of 8.4, 3.3, and 6.2 g/L, respectively. The peak viable cell densities of the three cell lines ranged from 1.3 × 10 7 to 1.8 × 10 7  cells/mL. These results show that the nutritionally balanced fed-batch medium and feeds worked well for other cell lines. During the medium development, we found that choline limitation caused a lower cell viability, a lower mAb titer, a higher mAb aggregate content, and a higher mannose-5 content. The optimal choline chloride to glucose ratio for the CHO cell fed-batch culture was determined. Our platform basal medium and feed media will shorten the medium-development time for mAb-producing cell lines.

  17. Corrosion testing using isotopes

    DOEpatents

    Hohorst, Frederick A.

    1995-12-05

    A method for determining the corrosion behavior of a material with respect to a medium in contact with the material by: implanting a substantially chemically inert gas in a matrix so that corrosion experienced by the material causes the inert gas to enter the medium; placing the medium in contact with the material; and measuring the amount of inert gas which enters the medium. A test sample of a material whose resistance to corrosion by a medium is to be tested, composed of: a body of the material, which body has a surface to be contacted by the medium; and a substantially chemically inert gas implanted into the body to a depth below the surface. A test sample of a material whose resistance to corrosion by a medium is to be tested, composed of: a substrate of material which is easily corroded by the medium, the substrate having a surface; a substantially chemically inert gas implanted into the substrate; and a sheet of the material whose resistance to corrosion is to be tested, the sheet being disposed against the surface of the substrate and having a defined thickness.

  18. A Novel Cell Type Enables B. subtilis to Escape from Unsuccessful Sporulation in Minimal Medium.

    PubMed

    Defeu Soufo, Hervé Joël

    2016-01-01

    Sporulation is the most enduring survival strategy developed by several bacterial species. However, spore development of the model organism Bacillus subtilis has mainly been studied by means of media or conditions optimized for the induction of sporogenesis. Here, I show that during prolonged growth during stationary phase in minimal medium, B. subtilis undergoes an asymmetric cell division that produces small and round-shaped, DNA containing cells. In contrast to wild-type cells, mutants harboring spo0A or spoIIIE / sftA double mutations neither sporulate nor produce this special cell type, providing evidence that the small round cells emerge from the abortion of endospore formation. In most cases observed, the small round cells arise in the presence of sigma H but absence of sigma F activity, different from cases of abortive sporulation described for rich media. These data suggest that in minimal media, many cells are able to initiate but fail to complete spore development, and therefore return to normal growth as rods. This work reveals that the continuation of asymmetric cell division, which results in the formation of the small round cells, is a way for cells to delay or escape from-unsuccessful-sporulation. Based on these findings, I suggest to name the here described cell type as "dwarf cells" to distinguish them from the well-known minicells observed in mutants defective in septum placement or proper chromosome partitioning.

  19. Effect of Soybean Casein Digest Agar Lot on Number of Bacillus stearothermophilus Spores Recovered †

    PubMed Central

    Pflug, I. J.; Smith, Geraldine M.; Christensen, Ronald

    1981-01-01

    In recent years it has become increasingly apparent that Bacillus stearothermophilus spores are affected by various environmental factors that influence the performance of the spores as biological indicators. One environmental factor is the recovery medium. The effect of different lots of commercial soybean casein digest agar on the number of colony-forming units per plate was examined in two series of experiments: (i) several lots of medium from two manufacturers were compared in single experiments, and (ii) paired media experiments with four lots of medium were carried out and yielded three-point survivor curves. The results demonstrate that commercial soybean casein digest agar is variable on a lot-to-lot basis. The variation was lowest when recovering unheated or minimally heated spores and increased greatly with the severity of heating. PMID:16345822

  20. A brief dataset on the model-based evaluation of the growth performance of Bacillus coagulans and l-lactic acid production in a lignin-supplemented medium.

    PubMed

    Glaser, Robert; Venus, Joachim

    2017-04-01

    The data presented in this article are related to the research article entitled "Model-based characterization of growth performance and l-lactic acid production with high optical purity by thermophilic Bacillus coagulans in a lignin-supplemented mixed substrate medium (R. Glaser and J. Venus, 2016) [1]". This data survey provides the information on characterization of three Bacillus coagulans strains. Information on cofermentation of lignocellulose-related sugars in lignin-containing media is given. Basic characterization data are supported by optical-density high-throughput screening and parameter adjustment to logistic growth models. Lab scale fermentation procedures are examined by model adjustment of a Monod kinetics-based growth model. Lignin consumption is analyzed using the data on decolorization of a lignin-supplemented minimal medium.

  1. Collaborative investigation of broth microdilution and semisolid agar dilution for in vitro susceptibility testing of Candida albicans.

    PubMed Central

    Shawar, R; Paetznick, V; Witte, Z; Ensign, L G; Anaissie, E; LaRocco, M

    1992-01-01

    A study was performed in two laboratories to evaluate the effect of growth medium and test methodology on inter- and intralaboratory variations in the MICs of amphotericin B (AMB), flucytosine (5FC), fluconazole (FLU), itraconazole (ITRA), and the triazole Sch 39304 (SCH) against 14 isolates of Candida albicans. Testing was performed by broth microdilution and semisolid agar dilution with the following media, buffered to pH 7.0 with morpholinepropanesulfonic acid (MOPS): buffered yeast nitrogen base (BYNB), Eagle's minimal essential medium (EMEM), RPMI 1640 medium (RPMI), and synthetic amino acid medium for fungi (SAAMF). Inocula were standardized spectrophotometrically, and endpoints were defined by the complete absence of growth for AMB and by no more than 25% of the growth in the drug-free control for all other agents. Comparative analyses of median MICs, as determined by each test method, were made for all drug-medium combinations. Both methods yielded similar (+/- 1 twofold dilution) median MICs for AMB in EMEM and RPMI, 5FC in all media, and FLU in EMEM, RPMI, and SAAMF. In contrast, substantial between-method variations in median MICs were seen for AMB in BYNB and SAAMF, FLU In BYNB, and ITRA and SCH in all media. Interlaboratory concordance of median MICs was good for AMB, 5FC, and FLU but poor for ITRA and SCH in all media. Endpoint determinations were analyzed by use of kappa statistical analyses for evaluating the strength of observer agreement. Moderate to almost perfect interlaboratory agreement occurred with AMB and 5FC in all media and with FLU in EMEM, RPMI, and SAAMF, irrespective of the test method. Slight to almost perfect interlaboratory agreement occurred with ITRA and SCH in EMEM, RPMI, and SAAMF when tested by semisolid agar dilution but not broth microdilution. Kappa values assessing intralaboratory agreement between methods were high for 5FC in all media, for AMB in BYNB, ENEM, and RPMI, and for FLU in EMEM, RPMI, and SAAMF. One laboratory, but not the other, reported substantial to almost perfect agreement between methods for ITRA, and SCH in EMEM, RPMI, and SAAMF. Both laboratories reported poor agreement between methods for the azoles in BYNB. Discrepancies noted in azole-BYNB combinations were largely due to the greater inhibitory effect of these agents in BYNB than in other media. These results indicate that the semisolid agar dilution and broth microdilution methods with EMEM or RPMI yield equivalent and reproducible MICs for AMB, 5FC, and FLU but not ITRA and SCH. PMID:1500502

  2. Collaborative investigation of broth microdilution and semisolid agar dilution for in vitro susceptibility testing of Candida albicans.

    PubMed

    Shawar, R; Paetznick, V; Witte, Z; Ensign, L G; Anaissie, E; LaRocco, M

    1992-08-01

    A study was performed in two laboratories to evaluate the effect of growth medium and test methodology on inter- and intralaboratory variations in the MICs of amphotericin B (AMB), flucytosine (5FC), fluconazole (FLU), itraconazole (ITRA), and the triazole Sch 39304 (SCH) against 14 isolates of Candida albicans. Testing was performed by broth microdilution and semisolid agar dilution with the following media, buffered to pH 7.0 with morpholinepropanesulfonic acid (MOPS): buffered yeast nitrogen base (BYNB), Eagle's minimal essential medium (EMEM), RPMI 1640 medium (RPMI), and synthetic amino acid medium for fungi (SAAMF). Inocula were standardized spectrophotometrically, and endpoints were defined by the complete absence of growth for AMB and by no more than 25% of the growth in the drug-free control for all other agents. Comparative analyses of median MICs, as determined by each test method, were made for all drug-medium combinations. Both methods yielded similar (+/- 1 twofold dilution) median MICs for AMB in EMEM and RPMI, 5FC in all media, and FLU in EMEM, RPMI, and SAAMF. In contrast, substantial between-method variations in median MICs were seen for AMB in BYNB and SAAMF, FLU In BYNB, and ITRA and SCH in all media. Interlaboratory concordance of median MICs was good for AMB, 5FC, and FLU but poor for ITRA and SCH in all media. Endpoint determinations were analyzed by use of kappa statistical analyses for evaluating the strength of observer agreement. Moderate to almost perfect interlaboratory agreement occurred with AMB and 5FC in all media and with FLU in EMEM, RPMI, and SAAMF, irrespective of the test method. Slight to almost perfect interlaboratory agreement occurred with ITRA and SCH in EMEM, RPMI, and SAAMF when tested by semisolid agar dilution but not broth microdilution. Kappa values assessing intralaboratory agreement between methods were high for 5FC in all media, for AMB in BYNB, ENEM, and RPMI, and for FLU in EMEM, RPMI, and SAAMF. One laboratory, but not the other, reported substantial to almost perfect agreement between methods for ITRA, and SCH in EMEM, RPMI, and SAAMF. Both laboratories reported poor agreement between methods for the azoles in BYNB. Discrepancies noted in azole-BYNB combinations were largely due to the greater inhibitory effect of these agents in BYNB than in other media. These results indicate that the semisolid agar dilution and broth microdilution methods with EMEM or RPMI yield equivalent and reproducible MICs for AMB, 5FC, and FLU but not ITRA and SCH.

  3. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ROOM AIR CONDITIONING UNITS AND HUMIDIFIERS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE), to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of th...

  4. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A FOSSIL FUEL-FIRED ELECTRICAL GENERATING STATION.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of the...

  5. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF FINE CHEMICALS USING BATCH PROCESSES.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of the...

  6. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF PAINTS PRIMARILY FOR METAL FINISHING.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  7. Screening of Natural Antimicrobials for Inhibition of E. coli O157:H7 in a Solidified Apple Juice Medium

    USDA-ARS?s Scientific Manuscript database

    Introduction: Naturally occurring antimicrobials such as plant extracts and essential oils have been used in the food industry for years. Due to increased consumer demand for minimally processed juices there has been increased interest in the use of novel antimicrobial compounds isolated from natur...

  8. Getting Set to Go: Upgrading Migration through an Innovative Educational Programme

    ERIC Educational Resources Information Center

    Khandelwal, Rajiv; Gilbert, Elon

    2007-01-01

    In the context of areas that have little prospect in the medium term of providing even minimal livelihoods locally for their overwhelming poor and increasingly migration-dependent rural populations, what does education for sustainable development (ESD) mean? Do efforts to qualitatively improve migration offer a viable strategy for reducing poverty…

  9. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A LOCAL BOARD OF EDUCATION IN NEW JERSEY.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at 30 small- to medium-sized businesses in the state of New Jersey. One of the si...

  10. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF SYSTEMS TO PRODUCE SEMICONDUCTORS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  11. WASTE REDUCTION ACTIVITIES AND OPTIONS AT A PRINTER OF FORMS AND SUPPLIES FOR THE LEGAL PROFESSION

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small-to medium-sized businesses in the state of New Jersey. One of the ...

  12. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A FOSSIL FUEL-FIRED ELECTRICAL GENERATING STATION

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  13. Improved Properties of Medium-Density Particleboard Manufactured from Saline Creeping Wild Rye and HDPE Plastic

    USDA-ARS?s Scientific Manuscript database

    Creeping Wild Rye (CWR), Leymus triticoides, is a salt-tolerant perennial grass used for mitigating the problems of saltilization and alkalization in drainage irrigation water and soil to minimize potential pollution of water streams. In this study, CWR was used as a raw material to manufacture med...

  14. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A LAMINATOR OF PAPER AND CARDBOARD PACKAGES.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  15. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR AN ELECTRICAL UTILITY TRANSMISSION SYSTEM MONITORING AND MAINTENANCE FACILITY

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  16. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR AN ELECTRICAL UTILITY TRANSMISSION SYSTEM MONITORING AND MAINTENANCE FACILITY.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  17. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTI- VITIES AND OPTIONS FOR A MANUFACTURER OF GENERAL PURPOSE PAINTS AND PAINTING SUPPLIES

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  18. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTI- VITIES AND OPTIONS FOR A FABRICATOR AND FINISHER OF STEEL COMPUTER CABINETS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  19. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A PRINTING PLATE PREPARATION SECTION OF A NEWSPAPER.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  20. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF PLASTIC CONTAINERS BY INJECTION MOLDING.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. ne of the ...

  1. Does the Medium Dictate the Message? Cultivating E-Communication in an Asynchronous Environment.

    ERIC Educational Resources Information Center

    Kiernan, Mary; Thomas, Pete; Woodroffe, Mark

    Virtual learning environments (VLEs) are often perceived by education establishments as an opportunity to widen access without traditional overheads. An integral part of most VLEs is asynchronous computer conferencing and on-line moderators must help students migrate quickly to the new virtual environment to minimize learning disruption. This…

  2. Spatial-temporal dynamics of Newtonian and viscoelastic turbulence in channel flow

    NASA Astrophysics Data System (ADS)

    Wang, Sung-Ning; Shekar, Ashwin; Graham, Michael

    2016-11-01

    Introducing a trace amount of polymer into liquid turbulent flows can result in substantial reduction of friction drag. This phenomenon has been widely used in fluid transport; however, the mechanism is not well understood. Past studies have found that in minimal domain turbulent simulations, there areoccasional time periods when flow exhibits features such as weaker vortices, lower friction drag and larger log-law slope; these have been denoted as "hibernatingturbulence". Here we address the question of whether similar behavior arises spatio-temporally in extended domains, focusing on turbulence at friction Reynolds numbers near transition and Weissenberg numbers resulting in low-medium drag reduction. By using image analysis and conditional sampling tools, we identify the hibernating states in extended domains and show that they display striking similarity as those in minimal domains. The hibernating states among different Weissenberg numbers exhibit similar flow statistics, suggesting they are unaltered by low to medium viscoelasticity. In addition, the polymer is much less stretched during hibernation. Finally, these hibernating states vanish as Reynolds number increases. However, they reoccur and gradually become dominant with increasing viscoelasticity.

  3. A complete collection of single-gene deletion mutants of Acinetobacter baylyi ADP1

    PubMed Central

    de Berardinis, Véronique; Vallenet, David; Castelli, Vanina; Besnard, Marielle; Pinet, Agnès; Cruaud, Corinne; Samair, Sumitta; Lechaplais, Christophe; Gyapay, Gabor; Richez, Céline; Durot, Maxime; Kreimeyer, Annett; Le Fèvre, François; Schächter, Vincent; Pezo, Valérie; Döring, Volker; Scarpelli, Claude; Médigue, Claudine; Cohen, Georges N; Marlière, Philippe; Salanoubat, Marcel; Weissenbach, Jean

    2008-01-01

    We have constructed a collection of single-gene deletion mutants for all dispensable genes of the soil bacterium Acinetobacter baylyi ADP1. A total of 2594 deletion mutants were obtained, whereas 499 (16%) were not, and are therefore candidate essential genes for life on minimal medium. This essentiality data set is 88% consistent with the Escherichia coli data set inferred from the Keio mutant collection profiled for growth on minimal medium, while 80% of the orthologous genes described as essential in Pseudomonas aeruginosa are also essential in ADP1. Several strategies were undertaken to investigate ADP1 metabolism by (1) searching for discrepancies between our essentiality data and current metabolic knowledge, (2) comparing this essentiality data set to those from other organisms, (3) systematic phenotyping of the mutant collection on a variety of carbon sources (quinate, 2-3 butanediol, glucose, etc.). This collection provides a new resource for the study of gene function by forward and reverse genetic approaches and constitutes a robust experimental data source for systems biology approaches. PMID:18319726

  4. Improvement of Storage Medium for Cultured Human Retinal Pigment Epithelial Cells Using Factorial Design.

    PubMed

    Pasovic, L; Utheim, T P; Reppe, S; Khan, A Z; Jackson, C J; Thiede, B; Berg, J P; Messelt, E B; Eidet, J R

    2018-04-09

    Storage of human retinal pigment epithelium (hRPE) can contribute to the advancement of cell-based RPE replacement therapies. The present study aimed to improve the quality of stored hRPE cultures by identifying storage medium additives that, alone or in combination, contribute to enhancing cell viability while preserving morphology and phenotype. hRPE cells were cultured in the presence of the silk protein sericin until pigmentation. Cells were then stored for 10 days in storage medium plus sericin and either one of 46 different additives. Individual effects of each additive on cell viability were assessed using epifluorescence microscopy. Factorial design identified promising additive combinations by extrapolating their individual effects. Supplementing the storage medium with sericin combined with adenosine, L-ascorbic acid and allopurinol resulted in the highest cell viability (98.6 ± 0.5%) after storage for three days, as measured by epifluorescence microscopy. Flow cytometry validated the findings. Proteomics identified 61 upregulated and 65 downregulated proteins in this storage group compared to the unstored control. Transmission electron microscopy demonstrated the presence of melanosomes after storage in the optimized medium. We conclude that the combination of adenosine, L-ascorbic acid, allopurinol and sericin in minimal essential medium preserves RPE pigmentation while maintaining cell viability during storage.

  5. 40 CFR Table 1a to Subpart Ec of... - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... limits HMIWI size Small Medium Large Averaging time 1 Methodfor demonstrating compliance 2 Particulate matter Milligrams per dry standard cubic meter (grains per dry standard cubic foot) 69 (0.03) 34 (0.015.../furans (grains per billion dry standard cubic feet) or nanograms per dry standard cubic meter TEQ (grains...

  6. 40 CFR Table 1b to Subpart Ec of... - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... HMIWI size Small Medium Large Averaging time 1 Method fordemonstrating compliance 2 Particulate matter Milligrams per dry standard cubic meter (grains per dry standard cubic foot) 66 (0.029) 22 (0.0095) 18 (0.../furans (grains per billion dry standard cubic feet) or nanograms per dry standard cubic meter TEQ (grains...

  7. Impact of Medium and Substrate on Growth of Pseudomonas Fluorescens Biofilms on Polyurethane Paint

    DTIC Science & Technology

    2011-02-01

    biofilm formation on polyurethane (PU) coatings, and to define how those parameters contribute to polyurethane biodegradation. We used a batch flow system...determine which factors best support the growth and persistence of Pseudomonas fluorescens biofilms . Factors that enhance biofilm formation and...AFRL-RX-WP-TP-2011-4131 IMPACT OF MEDIUM AND SUBSTRATE ON GROWTH OF PSEUDOMONAS FLUORESCENS BIOFILMS ON POLYURETHANE PAINT Wendy L. Goodson

  8. An improved agar medium for growth of Geobacillus thermoglucosidarius strains.

    PubMed

    Javed, M; Baghaei-Yazdi, N; Qin, W; Amartey, S

    2017-01-01

    Geobacillus species have potential applications in many biotechnological processes. They are fastidious in their vitamin and amino acid requirements. A new semi-defined agar medium (SDM) was developed which gave consistently high viable cell counts of various G. thermoglucosidasius strains (5×10 8 -6×10 8 cfu/ml) under aerobic conditions at 70°C. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Factors Affecting Exocellular Polysaccharide Production by Lactobacillus delbrueckii subsp. bulgaricus Grown in a Chemically Defined Medium†

    PubMed Central

    Petry, Sandrine; Furlan, Sylviane; Crepeau, Marie-Jeanne; Cerning, Jutta; Desmazeaud, Michel

    2000-01-01

    We developed a chemically defined medium (CDM) containing lactose or glucose as the carbon source that supports growth and exopolysaccharide (EPS) production of two strains of Lactobacillus delbrueckii subsp. bulgaricus. The factors found to affect EPS production in this medium were oxygen, pH, temperature, and medium constituents, such as orotic acid and the carbon source. EPS production was greatest during the stationary phase. Composition analysis of EPS isolated at different growth phases and produced under different fermentation conditions (varying carbon source or pH) revealed that the component sugars were the same. The EPS from strain L. delbrueckii subsp. bulgaricus CNRZ 1187 contained galactose and glucose, and that of strain L. delbrueckii subsp. bulgaricus CNRZ 416 contained galactose, glucose, and rhamnose. However, the relative proportions of the individual monosaccharides differed, suggesting that repeating unit structures can vary according to specific medium alterations. Under pH-controlled fermentation conditions, L. delbrueckii subsp. bulgaricus strains produced as much EPS in the CDM as in milk. Furthermore, the relative proportions of individual monosaccharides of EPS produced in pH-controlled CDM or in milk were very similar. The CDM we developed may be a useful model and an alternative to milk in studies of EPS production. PMID:10919802

  10. A minimal cost micropropagation protocol for Dianthus caryophyllus L.-- a commercially significant venture.

    PubMed

    Pant, Manu

    2016-03-01

    In tissue culture, high production cost of the products restricts their reach. Though tissue culture is a major strength in floriculture it is marred by pricing issues. Hence, we developed a complete regeneration low cost micropropagation protocol for an economically important floriculture crop, carnation (Dianthus caryophyllus L.). Successful regeneration of carnation from nodal explants on cost-efficient medium indicates that psyllium husk, sugar and RO water can effectively replace the conventional medium comprising agar, sucrose and distilled water. The protocol can contribute to increased carnation production at comparatively reduced cost, and there by encourage wide scale adoption by the common growers.

  11. Rigorous force field optimization principles based on statistical distance minimization

    DOE PAGES

    Vlcek, Lukas; Chialvo, Ariel A.

    2015-10-12

    We use the concept of statistical distance to define a measure of distinguishability between a pair of statistical mechanical systems, i.e., a model and its target, and show that its minimization leads to general convergence of the model’s static measurable properties to those of the target. Here we exploit this feature to define a rigorous basis for the development of accurate and robust effective molecular force fields that are inherently compatible with coarse-grained experimental data. The new model optimization principles and their efficient implementation are illustrated through selected examples, whose outcome demonstrates the higher robustness and predictive accuracy of themore » approach compared to other currently used methods, such as force matching and relative entropy minimization. We also discuss relations between the newly developed principles and established thermodynamic concepts, which include the Gibbs-Bogoliubov inequality and the thermodynamic length.« less

  12. Minimally invasive abdominal surgery: lux et veritas past, present, and future.

    PubMed

    Harrell, Andrew G; Heniford, B Todd

    2005-08-01

    Laparoscopic surgery has developed out of multiple technology innovations and the desire to see beyond the confines of the human body. As the instrumentation became more advanced, the application of this technique followed. By revisiting the historical developments that now define laparoscopic surgery, we can possibly foresee its future. A Medline search was performed of all the English-language literature. Further references were obtained through cross-referencing the bibliography cited in each work and using books from the authors' collection. Minimally invasive surgery is becoming important in almost every facet of abdominal surgery. Optical improvements, miniaturization, and robotic technology continue to define the frontier of minimally invasive surgery. Endoluminal resection surgery, image-guided surgical navigation, and remotely controlled robotics are not far from becoming reality. These and advances yet to be described will change laparoscopic surgery just as the electric light bulb did over 100 years ago.

  13. Pilates for Low Back Pain: Complete Republication of a Cochrane Review.

    PubMed

    Yamato, Tiê P; Maher, Christopher G; Saragiotto, Bruno T; Hancock, Mark J; Ostelo, Raymond W J G; Cabral, Cristina M N; Costa, Luciola C Menezes; Costa, Leonardo O P

    2016-06-01

    Systematic review. To determine the effects of the Pilates method for patients with nonspecific acute, subacute, or chronic low back pain. The Pilates method is one of the most common forms of intervention based on exercise used for treating patients with low back pain. However, its effectiveness is not well established. We conducted searches on CENTRAL, MEDLINE, EMBASE, CINAHL, PEDro, and SPORTDiscus up to March 2014. We included randomized controlled trials examining the effectiveness of Pilates in patients with acute, subacute, or chronic nonspecific low back pain. The outcomes evaluated were pain, disability, function, and global impression of recovery. Two independent reviewers screened for potentially eligible studies, assessed risk of bias, and extracted the data. We evaluated the overall quality of evidence using the GRADE approach and treatment effect sizes were described using mean differences and 95% confidence intervals. Searches retrieved 126 trials, of which 10 were included in the review (n = 510 participants). Seven studies were considered to have low risk of bias, and three were considered at high risk of bias. When compared to minimal intervention, Pilates reduces pain at short and intermediate term with low- to moderate-quality evidence and medium effect sizes. For disability, there is also a significant difference in favor to Pilates with low- to moderate-quality evidence and small effect size for short term and medium effect size for intermediate term compared with minimal intervention. It is unclear whether Pilates is better than other exercises for short-term pain, but there is low-quality evidence that Pilates reduces pain at intermediate term. For disability, there is moderate-quality evidence that there is no significant difference between Pilates and other exercises in either the short term or the intermediate term. There is low- to moderate-quality evidence that Pilates is more effective than minimal intervention with most of the effect sizes being considered medium. However, there is no conclusive evidence that Pilates is superior to other forms of exercises. 1.

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

    PubMed

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

    2004-02-01

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

  15. Importance of dosimetry protocol for cell irradiation on a low X-rays facility and consequences for the biological response.

    PubMed

    Dos Santos, Morgane; Paget, Vincent; Ben Kacem, Mariam; Trompier, François; Benadjaoud, Mohamed Amine; François, Agnès; Guipaud, Olivier; Benderitter, Marc; Milliat, Fabien

    2018-06-01

    The main objective of radiobiology is to establish links between doses and radiation-induced biological effects. In this context, well-defined dosimetry protocols are crucial to the determination of experimental protocols. This work proposes a new dosimetry protocol for cell irradiation in a SARRP and shows the importance of the modification of some parameters defined in dosimetry protocol for physical dose and biological outcomes. Once all parameters of the configuration were defined, dosimetry measurements with ionization chambers and EBT3 films were performed to evaluate the dose rate and the attenuation due to the cell culture medium. To evaluate the influence of changes in cell culture volume and/or additional filtration, 6-well plates containing EBT3 films with water were used to determine the impact on the physical dose at 80 kV. Then, experiments with the same irradiation conditions were performed by replacing EBT3 films by HUVECs. The biological response was assessed using clonogenic assay. Using a 0.15 mm copper filter lead to a variation of +1% using medium thickness of 0.104 cm to -8% using a medium thickness of 0.936 cm on the physical dose compare to the reference condition (0.313 cm). For the 1 mm aluminum filter, a variation of +8 to -40% for the same medium thickness conditions has been observed. Cells irradiated in the same conditions showed significant differences in survival fraction, corroborating the effects of dosimetric changes on physical dose. This work shows the importance of dosimetry in radiobiology studies and the need of an accurate description of the dosimetry protocol used for irradiation.

  16. Pump having pistons and valves made of electroactive actuators

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph (Inventor)

    1997-01-01

    The present invention provides a pump for inducing a displacement of a fluid from a first medium to a second medium, including a conduit coupled to the first and second media, a transducing material piston defining a pump chamber in the conduit and being transversely displaceable for increasing a volume of the chamber to extract the fluid from the first medium to the chamber and for decreasing the chamber volume to force the fluid from the chamber to the second medium, a first transducing material valve mounted in the conduit between the piston and the first medium and being transversely displaceable from a closed position to an open position to admit the fluid to the chamber, and control means for changing a first field applied to the piston to displace the piston for changing the chamber volume and for changing a second field applied to the first valve to change the position of the first valve.

  17. Method and apparatus for an increased output for a pumped laser using a moving aperture

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaPlante, M.J.; Bender, H.A. III; Carbaugh, W.D. Jr.

    1993-08-03

    An enhanced pumped laser system is described comprising: (a) at least one laser medium for forming a laser beam, said laser beam having a laser beam axis, (b) at least one means for pumping at least a portion of said at least one laser medium, wherein said pumping causes a population inversion in at least a portion of said at least one laser medium, (c) at least one means for defining an allowable laser beam path, wherein said allowable laser beam path is smaller than the cross-section of said at least one laser medium, (d) at least one means formore » sweeping said allowable laser beam path through said population inverted region of said at least one laser medium, (e) at least one first mirror to reflect at least a portion of said laser beam,« less

  18. Functional Bregman Divergence and Bayesian Estimation of Distributions (Preprint)

    DTIC Science & Technology

    2008-01-01

    shows that if the set of possible minimizers A includes EPF [F ], then g∗ = EPF [F ] minimizes the expectation of any Bregman divergence. Note the theorem...probability distribution PF defined over the set M. Let A be a set of functions that includes EPF [F ] if it exists. Suppose the function g∗ minimizes...the expected Bregman divergence between the random function F and any function g ∈ A such that g∗ = arg inf g∈A EPF [dφ(F, g)]. Then, if g∗ exists

  19. On a cost functional for H2/H(infinity) minimization

    NASA Technical Reports Server (NTRS)

    Macmartin, Douglas G.; Hall, Steven R.; Mustafa, Denis

    1990-01-01

    A cost functional is proposed and investigated which is motivated by minimizing the energy in a structure using only collocated feedback. Defined for an H(infinity)-norm bounded system, this cost functional also overbounds the H2 cost. Some properties of this cost functional are given, and preliminary results on the procedure for minimizing it are presented. The frequency domain cost functional is shown to have a time domain representation in terms of a Stackelberg non-zero sum differential game.

  20. Improved reproducibility of unit-cell parameters in macromolecular cryocrystallography by limiting dehydration during crystal mounting.

    PubMed

    Farley, Christopher; Burks, Geoffry; Siegert, Thomas; Juers, Douglas H

    2014-08-01

    In macromolecular cryocrystallography unit-cell parameters can have low reproducibility, limiting the effectiveness of combining data sets from multiple crystals and inhibiting the development of defined repeatable cooling protocols. Here, potential sources of unit-cell variation are investigated and crystal dehydration during loop-mounting is found to be an important factor. The amount of water lost by the unit cell depends on the crystal size, the loop size, the ambient relative humidity and the transfer distance to the cooling medium. To limit water loss during crystal mounting, a threefold strategy has been implemented. Firstly, crystal manipulations are performed in a humid environment similar to the humidity of the crystal-growth or soaking solution. Secondly, the looped crystal is transferred to a vial containing a small amount of the crystal soaking solution. Upon loop transfer, the vial is sealed, which allows transport of the crystal at its equilibrated humidity. Thirdly, the crystal loop is directly mounted from the vial into the cold gas stream. This strategy minimizes the exposure of the crystal to relatively low humidity ambient air, improves the reproducibility of low-temperature unit-cell parameters and offers some new approaches to crystal handling and cryoprotection.

  1. Improved reproducibility of unit-cell parameters in macromolecular cryocrystallography by limiting dehydration during crystal mounting

    PubMed Central

    Farley, Christopher; Burks, Geoffry; Siegert, Thomas; Juers, Douglas H.

    2014-01-01

    In macromolecular cryocrystallography unit-cell parameters can have low reproducibility, limiting the effectiveness of combining data sets from multiple crystals and inhibiting the development of defined repeatable cooling protocols. Here, potential sources of unit-cell variation are investigated and crystal dehydration during loop-mounting is found to be an important factor. The amount of water lost by the unit cell depends on the crystal size, the loop size, the ambient relative humidity and the transfer distance to the cooling medium. To limit water loss during crystal mounting, a threefold strategy has been implemented. Firstly, crystal manipulations are performed in a humid environment similar to the humidity of the crystal-growth or soaking solution. Secondly, the looped crystal is transferred to a vial containing a small amount of the crystal soaking solution. Upon loop transfer, the vial is sealed, which allows transport of the crystal at its equilibrated humidity. Thirdly, the crystal loop is directly mounted from the vial into the cold gas stream. This strategy minimizes the exposure of the crystal to relatively low humidity ambient air, improves the reproducibility of low-temperature unit-cell parameters and offers some new approaches to crystal handling and cryoprotection. PMID:25084331

  2. Metabolic Syndrome: Nonalcoholic Fatty Liver Disease.

    PubMed

    Williams, Tracy

    2015-08-01

    Although nonalcoholic fatty liver disease (NAFLD) is not one of the defining criteria for metabolic syndrome, it is a common hepatic manifestation. NAFLD includes a spectrum of histologic findings ranging from simple steatosis, known as nonalcoholic fatty liver, to nonalcoholic steatohepatitis (NASH). To make the diagnosis of NAFLD, other etiologies of steatosis or hepatitis, such as hepatotoxic drugs, excessive alcohol intake, congenital errors of metabolism, or viral hepatitis, must be ruled out. After ruling out other conditions, the diagnosis of NAFLD often is made clinically, but a definitive diagnosis of NASH requires liver biopsy. As with other complications of metabolic syndrome, insulin resistance is thought to be an underlying etiology of NAFLD. Management strategies attempt to reverse or improve insulin resistance while minimizing liver damage. The strongest evidence supports lifestyle modifications with weight loss, but there is some evidence to support bariatric surgery, medical therapy with insulin-sensitizing agents, and/or pharmacotherapy to promote weight loss. Cardiovascular disease is the major cause of mortality in patients with NAFLD, so management must include modification of cardiovascular risk factors. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

  3. Shewanella frigidimarina microbial fuel cells and the influence of divalent cations on current output.

    PubMed

    Fitzgerald, Lisa A; Petersen, Emily R; Leary, Dagmar H; Nadeau, Lloyd J; Soto, Carissa M; Ray, Richard I; Little, Brenda J; Ringeisen, Bradley R; Johnson, Glenn R; Vora, Gary J; Biffinger, Justin C

    2013-02-15

    The genes involved in the proposed pathway for Shewanella extracellular electron transfer (EET) are highly conserved. While extensive studies involving EET from a fresh water Shewanella microbe (S. oneidensis MR-1) to soluble and insoluble electron acceptors have been published, only a few reports have examined EET from marine strains of Shewanella. Thus, Shewanella frigidimarina (an isolate from Antarctic Sea ice) was used within miniature microbial fuel cells (mini-MFC) to evaluate potential power output. During the course of this study several distinct differences were observed between S. oneidensis MR-1 and S. frigidimarina under comparable conditions. The maximum power density with S. frigidimarina was observed when the anolyte was half-strength marine broth (1/2 MB) (0.28 μW/cm(2)) compared to Luria-Bertani (LB) (0.07 μW/cm(2)) or a defined growth minimal medium (MM) (0.02 μW/cm(2)). The systematic modification of S. frigidimarina cultured in 1/2 MB and LB with divalent cations shows that a maximum current output can be generated independent of internal ionic ohmic losses and the presence of external mediators. Published by Elsevier B.V.

  4. Regulation of galactokinase gene expression in Tetrahymena thermophila. II. Identification of 3,4-dihydroxyphenylalanine as a primary effector of adrenergic control of galactokinase expression.

    PubMed

    Ness, J C; Morse, D E

    1985-08-25

    Intracellular concentrations of catecholamines were determined in wild-type and mutant Tetrahymena thermophila, using the highly sensitive techniques of high-performance liquid chromatography and electro-chemical detection. Catecholamines were determined in these cell strains grown under various steady-state conditions, including those which initiate and maintain repression of galactokinase gene expression. Wild-type cells grown in defined minimal medium supplemented with 1% glycerol, exhibiting derepressed galactokinase synthesis, were found to contain considerable quantities of dopa (3,4-dihydroxyphenylalanine) and dopamine, but no detectable levels of either norepinephrine or epinephrine. Analyses of wild-type cells revealed a strong positive correlation between the internal concentration of dopa and expression of the galactokinase gene, both of which are regulated by exogenous carbohydrates, catecholamine agonists, or dibutyryl-cAMP; an analogous relationship between intracellular dopamine concentrations and galactokinase activity was not found. In addition, a correlation between intracellular dopa content and the phenotypic expression of galactokinase in various mutants deficient in the catecholamine biosynthetic pathway or in glucokinase further confirms the role of dopa as a primary effector in the regulation of galactokinase gene expression.

  5. Production of interferon-alpha in high cell density cultures of recombinant Escherichia coli and its single step purification from refolded inclusion body proteins.

    PubMed

    Babu, K R; Swaminathan, S; Marten, S; Khanna, N; Rinas, U

    2000-06-01

    Escherichia coli TG1 transformed with a temperature-regulated interferon-alpha expression vector was grown to high cell density in defined medium containing glucose as the sole carbon and energy source, utilizing a simple fed-batch process. Feeding was carried out to achieve an exponential increase in biomass at growth rates which minimized acetate production. Thermal induction of such high cell density cultures resulted in the production of approximately 4 g interferon-alpha/l culture broth. Interferon-alpha was produced exclusively in the form of insoluble inclusion bodies and was solubilized under denaturing conditions, refolded in the presence of arginine and purified to near homogeneity, utilizing single-step ion-exchange chromatography on Q-Sepharose. The yield of purified interferon-alpha was approximately 300 mg/l with respect to the original high cell density culture broth (overall yield of approximately 7.5% active interferon-alpha). The purified recombinant interferon-alpha was found by different criteria to be predominantly monomeric and possessed a specific bioactivity of approximately 2.5 x 10(8) IU/mg based on viral cytopathic assay.

  6. Transition from positive to neutral in mutation fixation along with continuing rising fitness in thermal adaptive evolution.

    PubMed

    Kishimoto, Toshihiko; Iijima, Leo; Tatsumi, Makoto; Ono, Naoaki; Oyake, Ayana; Hashimoto, Tomomi; Matsuo, Moe; Okubo, Masato; Suzuki, Shingo; Mori, Kotaro; Kashiwagi, Akiko; Furusawa, Chikara; Ying, Bei-Wen; Yomo, Tetsuya

    2010-10-21

    It remains to be determined experimentally whether increasing fitness is related to positive selection, while stationary fitness is related to neutral evolution. Long-term laboratory evolution in Escherichia coli was performed under conditions of thermal stress under defined laboratory conditions. The complete cell growth data showed common continuous fitness recovery to every 2°C or 4°C stepwise temperature upshift, finally resulting in an evolved E. coli strain with an improved upper temperature limit as high as 45.9°C after 523 days of serial transfer, equivalent to 7,560 generations, in minimal medium. Two-phase fitness dynamics, a rapid growth recovery phase followed by a gradual increasing growth phase, was clearly observed at diverse temperatures throughout the entire evolutionary process. Whole-genome sequence analysis revealed the transition from positive to neutral in mutation fixation, accompanied with a considerable escalation of spontaneous substitution rate in the late fitness recovery phase. It suggested that continually increasing fitness not always resulted in the reduction of genetic diversity due to the sequential takeovers by fit mutants, but caused the accumulation of a considerable number of mutations that facilitated the neutral evolution.

  7. Distance majorization and its applications.

    PubMed

    Chi, Eric C; Zhou, Hua; Lange, Kenneth

    2014-08-01

    The problem of minimizing a continuously differentiable convex function over an intersection of closed convex sets is ubiquitous in applied mathematics. It is particularly interesting when it is easy to project onto each separate set, but nontrivial to project onto their intersection. Algorithms based on Newton's method such as the interior point method are viable for small to medium-scale problems. However, modern applications in statistics, engineering, and machine learning are posing problems with potentially tens of thousands of parameters or more. We revisit this convex programming problem and propose an algorithm that scales well with dimensionality. Our proposal is an instance of a sequential unconstrained minimization technique and revolves around three ideas: the majorization-minimization principle, the classical penalty method for constrained optimization, and quasi-Newton acceleration of fixed-point algorithms. The performance of our distance majorization algorithms is illustrated in several applications.

  8. Corrosion testing using isotopes

    DOEpatents

    Hohorst, F.A.

    1995-12-05

    A method is described for determining the corrosion behavior of a material with respect to a medium in contact with the material by: implanting a substantially chemically inert gas in a matrix so that corrosion experienced by the material causes the inert gas to enter the medium; placing the medium in contact with the material; and measuring the amount of inert gas which enters the medium. A test sample of a material whose resistance to corrosion by a medium is to be tested is described composed of: a body of the material, which body has a surface to be contacted by the medium; and a substantially chemically inert gas implanted into the body to a depth below the surface. A test sample of a material whose resistance to corrosion by a medium is to be tested is described composed of: a substrate of material which is easily corroded by the medium, the substrate having a surface; a substantially chemically inert gas implanted into the substrate; and a sheet of the material whose resistance to corrosion is to be tested, the sheet being disposed against the surface of the substrate and having a defined thickness. 3 figs.

  9. Human serum-derived protein removes the need for coating in defined human pluripotent stem cell culture

    PubMed Central

    Pijuan-Galitó, Sara; Tamm, Christoffer; Schuster, Jens; Sobol, Maria; Forsberg, Lars; Merry, Catherine L. R.; Annerén, Cecilia

    2016-01-01

    Reliable, scalable and time-efficient culture methods are required to fully realize the clinical and industrial applications of human pluripotent stem (hPS) cells. Here we present a completely defined, xeno-free medium that supports long-term propagation of hPS cells on uncoated tissue culture plastic. The medium consists of the Essential 8 (E8) formulation supplemented with inter-α-inhibitor (IαI), a human serum-derived protein, recently demonstrated to activate key pluripotency pathways in mouse PS cells. IαI efficiently induces attachment and long-term growth of both embryonic and induced hPS cell lines when added as a soluble protein to the medium at seeding. IαI supplementation efficiently supports adaptation of feeder-dependent hPS cells to xeno-free conditions, clonal growth as well as single-cell survival in the absence of Rho-associated kinase inhibitor (ROCKi). This time-efficient and simplified culture method paves the way for large-scale, high-throughput hPS cell culture, and will be valuable for both basic research and commercial applications. PMID:27405751

  10. CRISPR/Cas9-Mediated Mutagenesis of Human Pluripotent Stem Cells in Defined Xeno-Free E8 Medium.

    PubMed

    Soh, Chew-Li; Huangfu, Danwei

    2017-01-01

    The recent advent of engineered nucleases including the CRISPR/Cas9 system has greatly facilitated genome manipulation in human pluripotent stem cells (hPSCs). In addition to facilitating hPSC-based disease studies, the application of genome engineering in hPSCs has also opened up new avenues for cell replacement therapy. To improve consistency and reproducibility of hPSC-based studies, and to meet the safety and regulatory requirements for clinical translation, it is necessary to use a defined, xeno-free cell culture system. This chapter describes protocols for CRISPR/Cas9 genome editing in an inducible Cas9 hPSC-based system, using cells cultured in chemically defined, xeno-free E8 Medium on a recombinant human vitronectin substrate. We detail procedures for the design and transfection of CRISPR guide RNAs, colony selection, and the expansion and validation of clonal mutant lines, all within this fully defined culture condition. These methods may be applied to a wide range of genome-engineering applications in hPSCs, including those that utilize different types of site-specific nucleases such as zinc finger nucleases (ZFNs) and TALENs, and form a closer step towards clinical utility of these cells.

  11. Rapid identification of Clostridium species by high-pressure liquid chromatography.

    PubMed Central

    Harpold, D J; Wasilauskas, B L; O'Connor, M L

    1985-01-01

    High-pressure liquid chromatography was evaluated as a rapid means of identifying various species of clostridia. Isolates were inoculated into a defined medium and incubated aerobically for 1 h at 35 degrees C. The organisms were removed, and the supernatants were derivatized for 1 min at room temperature by the addition of o-phthalaldehyde. The total time required to run each chromatogram was approximately 50 min. Standardized peak heights for each medium component and any new peaks formed were calculated for each isolate and compared with those for uninoculated control medium. Multiple isolates of various Clostridium species gave consistent patterns of medium utilization that could be used for identification. This rapid method can easily be adapted for laboratory use and has the potential for automation. PMID:3905852

  12. [Amyloidosis maculosa: diagnosis in primary care].

    PubMed

    Toribio da Pena, S R; Olmos, O; Borbujo, J; Bastos Amigo, J A; Jiménez-Sánchez, F; Alonso, A

    1990-01-01

    Amyloidosis maculosa is a clinical entity with low incidence factor in our medium, which basically affects middle-aged women. The lesion is characterised by the presence of poorly defined, hyperpigmented, brownish or greyish maculae that converge and focus basically on the upper back and shoulders, usually accompanied by pruritus. Three patients were erroneously catalogued for years as having pityriasis versicolor. Two of these patients presented a typical clinical amyloidosis maculosa, and the third presented a less common manifestation of the disease: a single, well-defined lesion in the subscapular region. We believe that the approach to the diagnosis of pityriasis versicolor with hyperpigmented lesions that do not respond to specific treatment should be revised. Although amyloidosis maculosa has a low incidence in our medium, it is an entity which should not be discarded in these cases.

  13. Statistical optimization of growth medium for the production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin from Fusarium oxysporum KFCC 11363P.

    PubMed

    Lee, Hee-Seok; Song, Hyuk-Hwan; An, Joong-Hoon; Shin, Cha-Gyun; Lee, Gung Pyo; Lee, Chan

    2008-01-01

    The production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin (BEA) was studied in submerged cultures of Fusarium oxysporum KFCC 11363P isolated in Korea. The influences of various factors on mycelia growth and BEA production were examined in both complete and chemically defined culture media. The mycelia growth and BEA production were highest in Fusarium defined medium. The optimal carbon and nitrogen sources for maximizing BEA production were glucose and NaNO3, respectively. The carbon/ nitrogen ratio for maximal production of BEA was investigated using response surface methodology (RSM). Equations derived by differentiation of the RSM model revealed that the production of BEA was maximal when using 108 mM glucose and 25 mM NaNO3.

  14. Early Success Is Vital in Minimal Worksite Wellness Interventions at Small Worksites

    ERIC Educational Resources Information Center

    Ablah, Elizabeth; Dong, Frank; Konda, Kurt; Konda, Kelly; Armbruster, Sonja; Tuttle, Becky

    2015-01-01

    Intervention: In an effort to increase physical activity, 15 workplaces participated in a minimal-contact 10,000-steps-a-day program sponsored by the Sedgwick County Health Department in 2007 and 2008. Pedometers were provided to measure participants' weekly steps for the 10-week intervention. Method: Participants were defined as those who…

  15. Discrepant Results in a 2-D Marble Collision

    ERIC Educational Resources Information Center

    Kalajian, Peter

    2013-01-01

    Video analysis of 2-D collisions is an excellent way to investigate conservation of linear momentum. The often-desired experimental design goal is to minimize the momentum loss in order to demonstrate the conservation law. An air table with colliding pucks is an ideal medium for this experiment, but such equipment is beyond the budget of many…

  16. Supervisory Rotation: Impact on an Academic Library Reference Staff.

    ERIC Educational Resources Information Center

    Perdue, Bob; Piotrowski, Chris

    The results of a managerial rotation program in a medium-sized academic library reference department are presented. After meeting certain minimal eligibility requirements, librarians in this department take turns on a 2-year cycle serving as head of the department. This case study is used as a model to assess both the advantages and disadvantages…

  17. Effect of calcium in assay medium on D value of Bacillus stearothermophilus ATCC 7953 spores.

    PubMed

    Sasaki, K; Shintani, H; Itoh, J; Kamogawa, T; Kajihara, Y

    2000-12-01

    The D value of commercial biological indicator spore strips using Bacillus stearothermophilus ATCC 7953 was increased by higher calcium concentrations in assay media. The calcium concentration in assay media varied among the manufacturers. The calcium concentration in assay media is an important factor to consider to minimize the variation of D value.

  18. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF FIRE RETARDANT PLASTIC PELLETS AND HOT MELT ADHESIVES.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of the...

  19. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF WIRE STOCK USED FOR PRODUCTION OF METAL ITEMS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) to assist in conducting waste minimization assessments at thirty small- to medium-sized businesses in the state of New Jersey. One of th...

  20. Apoprotein isolation and activation, and vibrational structure of the Helicobacter mustelae iron urease

    PubMed Central

    Carter, Eric L.; Proshlyakov, Denis A.; Hausinger, Robert P.

    2011-01-01

    The micro-aerophilic pathogen Helicobacter mustelae synthesizes an oxygen-labile, iron-containing urease (UreA2B2) in addition to its standard nickel-containing enzyme (UreAB). An apoprotein form of the iron urease was prepared from ureA2B2-expressing recombinant Escherichia coli cells that were grown in minimal medium. Temperature-dependent circular dichroism measurements of holoprotein and apoprotein demonstrate an enhancement of thermal stability associated with the UreA2B2 metallocenter. In parallel to the situation reported for nickel activation of the standard urease apoprotein, incubation of UreA2B2 apoprotein with ferrous ions and bicarbonate generated urease activity in a portion of the nascent active sites. In addition, ferrous ions were shown to be capable of reductively activating the oxidized metallocenter. Resonance Raman spectra of the inactive, aerobically-purified UreA2B2 holoprotein exhibit vibrations at 495 cm−1 and 784 cm−1, consistent with νs and νas modes of an Fe(III)-O-Fe(III) center; these modes undergo downshifts upon binding of urea and were unaffected by changes in pH. The low-frequency mode also exhibits an isotopic shift from 497 to 476 cm−1 upon 16O/18O bulk water isotope substitution. Expression of subunits of the conventional nickel-containing Klebsiella aerogenes urease in cells grown in rich medium without nickel resulted in iron incorporation into a portion of the protein. The inactive iron-loaded species exhibited a UV-visible spectrum similar to oxidized UreA2B2 and was capable of being reductively activated under anoxic conditions. Results from these studies more clearly define the formation and unique properties of the iron urease metallocenter. PMID:22196017

  1. The effect of Me2SO overexposure during cryopreservation on HOS TE85 and hMSC viability, growth and quality.

    PubMed

    Morris, Timothy J; Picken, Andrew; Sharp, Duncan M C; Slater, Nigel K H; Hewitt, Christopher J; Coopman, Karen

    2016-12-01

    With the cell therapy industry continuing to grow, the ability to preserve clinical grade cells, including mesenchymal stem cells (MSCs), whilst retaining cell viability and function remains critical for the generation of off-the-shelf therapies. Cryopreservation of MSCs, using slow freezing, is an established process at lab scale. However, the cytotoxicity of cryoprotectants, like Me 2 SO, raises questions about the impact of prolonged cell exposure to cryoprotectant at temperatures >0 °C during processing of large cell batches for allogenic therapies prior to rapid cooling in a controlled rate freezer or in the clinic prior to administration. Here we show that exposure of human bone marrow derived MSCs to Me 2 SO for ≥1 h before freezing, or after thawing, degrades membrane integrity, short-term cell attachment efficiency and alters cell immunophenotype. After 2 h's exposure to Me 2 SO at 37 °C post-thaw, membrane integrity dropped to ∼70% and only ∼50% of cells retained the ability to adhere to tissue culture plastic. Furthermore, only 70% of the recovered MSCs retained an immunophenotype consistent with the ISCT minimal criteria after exposure. We also saw a similar loss of membrane integrity and attachment efficiency after exposing osteoblast (HOS TE85) cells to Me 2 SO before, and after, cryopreservation. Overall, these results show that freezing medium exposure is a critical determinant of product quality as process scale increases. Defining and reporting cell sensitivity to freezing medium exposure, both before and after cryopreservation, enables a fair judgement of how scalable a particular cryopreservation process can be, and consequently whether the therapy has commercial feasibility. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Accounting for patient size in the optimization of dose and image quality of pelvis cone beam CT protocols on the Varian OBI system

    PubMed Central

    Moore, Craig S; Horsfield, Carl J; Saunderson, John R; Beavis, Andrew W

    2015-01-01

    Objective: The purpose of this study was to develop size-based radiotherapy kilovoltage cone beam CT (CBCT) protocols for the pelvis. Methods: Image noise was measured in an elliptical phantom of varying size for a range of exposure factors. Based on a previously defined “small pelvis” reference patient and CBCT protocol, appropriate exposure factors for small, medium, large and extra-large patients were derived which approximate the image noise behaviour observed on a Philips CT scanner (Philips Medical Systems, Best, Netherlands) with automatic exposure control (AEC). Selection criteria, based on maximum tube current–time product per rotation selected during the radiotherapy treatment planning scan, were derived based on an audit of patient size. Results: It has been demonstrated that 110 kVp yields acceptable image noise for reduced patient dose in pelvic CBCT scans of small, medium and large patients, when compared with manufacturer's default settings (125 kVp). Conversely, extra-large patients require increased exposure factors to give acceptable images. 57% of patients in the local population now receive much lower radiation doses, whereas 13% require higher doses (but now yield acceptable images). Conclusion: The implementation of size-based exposure protocols has significantly reduced radiation dose to the majority of patients with no negative impact on image quality. Increased doses are required on the largest patients to give adequate image quality. Advances in knowledge: The development of size-based CBCT protocols that use the planning CT scan (with AEC) to determine which protocol is appropriate ensures adequate image quality whilst minimizing patient radiation dose. PMID:26419892

  3. Modeling Endovascular Coils as Heterogeneous Porous Media

    NASA Astrophysics Data System (ADS)

    Yadollahi Farsani, H.; Herrmann, M.; Chong, B.; Frakes, D.

    2016-12-01

    Minimally invasive surgeries are the stat-of-the-art treatments for many pathologies. Treating brain aneurysms is no exception; invasive neurovascular clipping is no longer the only option and endovascular coiling has introduced itself as the most common treatment. Coiling isolates the aneurysm from blood circulation by promoting thrombosis within the aneurysm. One approach to studying intra-aneurysmal hemodynamics consists of virtually deploying finite element coil models and then performing computational fluid dynamics. However, this approach is often computationally expensive and requires extensive resources to perform. The porous medium approach has been considered as an alternative to the conventional coil modeling approach because it lessens the complexities of computational fluid dynamics simulations by reducing the number of mesh elements needed to discretize the domain. There have been a limited number of attempts at treating the endovascular coils as homogeneous porous media. However, the heterogeneity associated with coil configurations requires a more accurately defined porous medium in which the porosity and permeability change throughout the domain. We implemented this approach by introducing a lattice of sample volumes and utilizing techniques available in the field of interactive computer graphics. We observed that the introduction of the heterogeneity assumption was associated with significant changes in simulated aneurysmal flow velocities as compared to the homogeneous assumption case. Moreover, as the sample volume size was decreased, the flow velocities approached an asymptotical value, showing the importance of the sample volume size selection. These results demonstrate that the homogeneous assumption for porous media that are inherently heterogeneous can lead to considerable errors. Additionally, this modeling approach allowed us to simulate post-treatment flows without considering the explicit geometry of a deployed endovascular coil mass, greatly simplifying computation.

  4. A Novel Cell Type Enables B. subtilis to Escape from Unsuccessful Sporulation in Minimal Medium

    PubMed Central

    Defeu Soufo, Hervé Joël

    2016-01-01

    Sporulation is the most enduring survival strategy developed by several bacterial species. However, spore development of the model organism Bacillus subtilis has mainly been studied by means of media or conditions optimized for the induction of sporogenesis. Here, I show that during prolonged growth during stationary phase in minimal medium, B. subtilis undergoes an asymmetric cell division that produces small and round-shaped, DNA containing cells. In contrast to wild-type cells, mutants harboring spo0A or spoIIIE/sftA double mutations neither sporulate nor produce this special cell type, providing evidence that the small round cells emerge from the abortion of endospore formation. In most cases observed, the small round cells arise in the presence of sigma H but absence of sigma F activity, different from cases of abortive sporulation described for rich media. These data suggest that in minimal media, many cells are able to initiate but fail to complete spore development, and therefore return to normal growth as rods. This work reveals that the continuation of asymmetric cell division, which results in the formation of the small round cells, is a way for cells to delay or escape from—unsuccessful—sporulation. Based on these findings, I suggest to name the here described cell type as “dwarf cells” to distinguish them from the well-known minicells observed in mutants defective in septum placement or proper chromosome partitioning. PMID:27891124

  5. Transcriptional Profiling of Caulobacter crescentus during Growth on Complex and Minimal Media

    PubMed Central

    Hottes, Alison K.; Meewan, Maliwan; Yang, Desiree; Arana, Naomi; Romero, Pedro; McAdams, Harley H.; Stephens, Craig

    2004-01-01

    Microarray analysis was used to examine gene expression in the freshwater oligotrophic bacterium Caulobacter crescentus during growth on three standard laboratory media, including peptone-yeast extract medium (PYE) and minimal salts medium with glucose or xylose as the carbon source. Nearly 400 genes (approximately 10% of the genome) varied significantly in expression between at least two of these media. The differentially expressed genes included many encoding transport systems, most notably diverse TonB-dependent outer membrane channels of unknown substrate specificity. Amino acid degradation pathways constituted the largest class of genes induced in PYE. In contrast, many of the genes upregulated in minimal media encoded enzymes for synthesis of amino acids, including incorporation of ammonia and sulfate into glutamate and cysteine. Glucose availability induced expression of genes encoding enzymes of the Entner-Doudoroff pathway, which was demonstrated here through mutational analysis to be essential in C. crescentus for growth on glucose. Xylose induced expression of genes encoding several hydrolytic exoenzymes as well as an operon that may encode a novel pathway for xylose catabolism. A conserved DNA motif upstream of many xylose-induced genes was identified and shown to confer xylose-specific expression. Xylose is an abundant component of xylan in plant cell walls, and the microarray data suggest that in addition to serving as a carbon source for growth of C. crescentus, this pentose may be interpreted as a signal to produce enzymes associated with plant polymer degradation. PMID:14973021

  6. Production of novel antibiotics zeamines through optimizing Dickeya zeae fermentation conditions.

    PubMed

    Liao, Lisheng; Cheng, Yingying; Liu, Shiyin; Zhou, Jianuan; An, Shuwen; Lv, Mingfa; Chen, Yufan; Gu, Yanfang; Chen, Shaohua; Zhang, Lian-Hui

    2014-01-01

    Dickeya zeae strain EC1 was recently shown to produce a new type of phytotoxins designated as zeamine and zeamine II, which are potent wide-spectrum antibiotics against Gram-positive and Gram-negative bacterial pathogens, suggesting their promising potential as clinical medicines. In this study, the optimized medium composition and culture conditions for biosynthesis of novel antibiotics zeamines have been established by using response surface methodology, largely increasing the yield of zeamines from original about 7.35 µg · mL(-1) in minimal medium to about 150 µg · mL(-1) in LS5 medium. The study identified the major factors contributing to zeamines production, which include nitrate, sucrose, asparaginate, mineral elements Mg2+ and K+, and optimized amount of phosphate. In addition, the results showed that overexpression of zmsK in D. zeae strain EC1 could further increase zeamines yield to about 180 µg · mL(-1) in LS5 medium. The findings from this study could facilitate further characterization and utilization of these two novel antibiotics, and also provide useful clues for understanding the regulatory mechanisms that govern D. zeae virulence.

  7. Medium engineering for enhanced production of undecylprodigiosin antibiotic in Streptomyces coelicolor using oil palm biomass hydrolysate as a carbon source.

    PubMed

    Bhatia, Shashi Kant; Lee, Bo-Rahm; Sathiyanarayanan, Ganesan; Song, Hun-Seok; Kim, Junyoung; Jeon, Jong-Min; Kim, Jung-Ho; Park, Sung-Hee; Yu, Ju-Hyun; Park, Kyungmoon; Yang, Yung-Hun

    2016-10-01

    In this study, a biosugar obtained from empty fruit bunch (EFB) of oil palm by hot water treatment and subsequent enzymatic saccharification was used for undecylprodigiosin production, using Streptomyces coelicolor. Furfural is a major inhibitor present in EFB hydrolysate (EFBH), having a minimum inhibitory concentration (MIC) of 1.9mM, and it reduces utilization of glucose (27%), xylose (59%), inhibits mycelium formation, and affects antibiotic production. Interestingly, furfural was found to be a good activator of undecylprodigiosin production in S. coelicolor, which enhanced undecylprodigiosin production by up to 52%. Optimization by mixture analysis resulted in a synthetic medium containing glucose:furfural:ACN:DMSO (1%, 2mM, 0.2% and 0.3%, respectively). Finally, S. coelicolor was cultured in a fermenter in minimal medium with EFBH as a carbon source and addition of the components described above. This yielded 4.2μg/mgdcw undecylprodigiosin, which was 3.2-fold higher compared to that in un-optimized medium. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. A Proteomic Study of Clavibacter Michiganensis Subsp. Michiganensis Culture Supernatants

    PubMed Central

    Hiery, Eva; Poetsch, Ansgar; Moosbauer, Tanja; Amin, Bushra; Hofmann, Jörg; Burkovski, Andreas

    2015-01-01

    Clavibacter michiganensis, subsp. michiganensis is a Gram-positive plant pathogen infecting tomato (Solanum lycopersicum). Despite a considerable economic importance due to significant losses of infected plants and fruits, knowledge about virulence factors of C. michiganensis subsp. michiganensis and host-pathogen interactions on a molecular level are rather limited. In the study presented here, the proteome of culture supernatants from C. michiganensis subsp. michiganensis NCPPB382 was analyzed. In total, 1872 proteins were identified in M9 and 1766 proteins in xylem mimicking medium. Filtration of supernatants before protein precipitation reduced these to 1276 proteins in M9 and 976 proteins in the xylem mimicking medium culture filtrate. The results obtained indicate that C. michiganensis subsp. michiganensis reacts to a sucrose- and glucose-depleted medium similar to the xylem sap by utilizing amino acids and host cell polymers as well as their degradation products, mainly peptides, amino acids and various C5 and C6 sugars. Interestingly, the bacterium expresses the previously described virulence factors Pat-1 and CelA not exclusively after host cell contact in planta but already in M9 minimal and xylem mimicking medium. PMID:28248277

  9. Waste reduction plan for The Oak Ridge National Laboratory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schultz, R.M.

    1990-04-01

    The Oak Ridge National Laboratory (ORNL) is a multipurpose Research and Development (R D) facility. These R D activities generate numerous small waste streams. Waste minimization is defined as any action that minimizes the volume or toxicity of waste by avoiding its generation or recycling. This is accomplished by material substitution, changes to processes, or recycling wastes for reuse. Waste reduction is defined as waste minimization plus treatment which results in volume or toxicity reduction. The ORNL Waste Reduction Program will include both waste minimization and waste reduction efforts. Federal regulations, DOE policies and guidelines, increased costs and liabilities associatedmore » with the management of wastes, limited disposal options and facility capacities, and public consciousness have been motivating factors for implementing comprehensive waste reduction programs. DOE Order 5820.2A, Section 3.c.2.4 requires DOE facilities to establish an auditable waste reduction program for all LLW generators. In addition, it further states that any new facilities, or changes to existing facilities, incorporate waste minimization into design considerations. A more recent DOE Order, 3400.1, Section 4.b, requires the preparation of a waste reduction program plan which must be reviewed annually and updated every three years. Implementation of a waste minimization program for hazardous and radioactive mixed wastes is sited in DOE Order 5400.3, Section 7.d.5. This document has been prepared to address these requirements. 6 refs., 1 fig., 2 tabs.« less

  10. Genome-wide transcriptome analysis of Clavibacter michiganensis subsp. michiganensis grown in xylem mimicking medium.

    PubMed

    Hiery, Eva; Adam, Susanne; Reid, Stephen; Hofmann, Jörg; Sonnewald, Sophia; Burkovski, Andreas

    2013-12-01

    The interaction between Clavibacter michiganensis subsp. michiganensis with its host, the tomato plant (Solanum lycopersicum), is poorly understood and only few virulence factors are known. While studying of the bacteria in planta is time-consuming and difficult, the analysis in vitro would facilitate research. Therefore, a xylem mimicking medium (XMM) for C. michiganensis subsp. michiganensis was established in this study based on an apoplast medium for Xanthomonas campestris pv. vesicatoria. In contrast to the apoplast medium, XMM contains no sugars, but amino acids which serve as nitrogen and carbon source. As a result, growth in XMM induced transcriptional changes of genes encoding putative sugar, amino acid and iron uptake systems. In summary, mRNA levels of about 8% of all C. michiganensis subsp. michiganensis genes were changed when XMM-grown bacteria were compared to M9 minimal medium-grown cells. Almost no transcriptional changes of genes encoding hydrolytic enzymes were detected, leading to the idea that XMM reflects the situation in the beginning of infection and therefore allows the characterization of virulence factors in this early stage of infection. The addition of the plant wound substance acetosyringone to the XMM medium led to a change in transcript amount, including genes coding for proteins involved in protein transport, iron uptake and regulation processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Petroleum Jelly: A Novel Medium for Ocular Ultrasound.

    PubMed

    Engelbert, Patrick R; Palma, James K

    2015-08-01

    Ocular ultrasound is a useful emergency department imaging modality for evaluation of many conditions, such as retinal detachment, vitreous detachment, vitreous hemorrhage, and elevated intracranial pressure. Obtaining satisfactory ocular ultrasound images requires the use of a medium that eliminates the air interface between the patient's eye and the transducer. Ultrasound gel is most commonly used; however, the use of a transparent dressing applied to the closed eye prior to the application of gel has also been described as a suitable technique. Ocular ultrasound is performed with the high-frequency linear array transducer using a medium to eliminate the air interface between the eye and the transducer. Although ultrasound gel is most frequently used, it can cause minor eye irritation. Placing a transparent dressing over a closed eye prior to application of gel can eliminate the eye irritation. However, our experience in training >500 students in ocular ultrasound has shown that air is frequently introduced underneath the dressing, which leads to poor-quality images. This article introduces petroleum jelly as a medium for ocular ultrasound. By applying a layer of petroleum jelly over the closed eye and allowing it to warm via body heat for 30 to 45 s, this medium can both minimize patient discomfort and provide easily obtainable, high-quality ocular ultrasound images. This article introduces petroleum jelly as a safe, comfortable, and effective medium for ocular ultrasound examination. Published by Elsevier Inc.

  12. A Simple Defined Medium for the Production of True Diketopiperazines in Xylella fastidiosa and Their Identification by Ultra-Fast Liquid Chromatography-Electrospray Ionization Ion Trap Mass Spectrometry.

    PubMed

    Silva, Michelli Massaroli da; Andrade, Moacir Dos Santos; Bauermeister, Anelize; Merfa, Marcus Vinícius; Forim, Moacir Rossi; Fernandes, João Batista; Vieira, Paulo Cezar; Silva, Maria Fátima das Graças Fernandes da; Lopes, Norberto Peporine; Machado, Marcos Antônio; Souza, Alessandra Alves de

    2017-06-13

    Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium ( X. fastidiosa medium or XFM) containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa , which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa , which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown.

  13. On the mechanism of pulsed laser ablation of phthalocyanine nanoparticles in an aqueous medium

    NASA Astrophysics Data System (ADS)

    Kogan, Boris; Malimonenko, Nicholas; Butenin, Alexander; Novoseletsky, Nicholas; Chizhikov, Sergei

    2018-06-01

    Laser ablation of phthalocyanine nanoparticles has potential for cancer treatment. The ablation is accompanied by the formation of microbubbles and the sublimation of nanoparticles. This was investigated in a liquid medium simulating tissue using optical-acoustic and spectral-luminescent methods. The thresholds for the appearance of microbubbles have been determined as a function of nanoparticle size. For the minimal size particles (80 nm) this threshold is equal to about 20–25 mJ cm‑2 and for the maximal size particles (230 nm) this threshold is equal to about 7 mJ cm‑2. It was estimated that the particle temperature at which bubbles arise is near 145 °С.

  14. Rat pancreatic islet size standardization by the "hanging drop" technique.

    PubMed

    Cavallari, G; Zuellig, R A; Lehmann, R; Weber, M; Moritz, W

    2007-01-01

    Rejection and hypoxia are the main factors that limit islet engraftment in the recipient liver in the immediate posttransplant period. Recently authors have reported a negative relationship of graft function and islet size, concluding that small islets are superior to large islets. Islets can be dissociated into single cells and reaggregated into so called "pseudoislets," which are functionally equivalent to intact islets but exhibit reduced immunogenicity. The aim of our study was develop a technique that enabled one to obtain pseudoislets of defined, preferably small, dimensions. Islets were harvested from Lewis rats by the collagenase digestion procedure. After purification, the isolated islets were dissociated into single cells by trypsin digestion. Fractions with different cell numbers were seeded into single drops onto cell culture dishes, which were inverted and incubated for 5 to 8 days under cell culture conditions. Newly formed pseudoislets were analyzed for dimension, morphology, and cellular composition. The volume of reaggregated pseudoislets strongly correlated with the cell number (r(2) = .995). The average diameter of a 250-cell aggregate was 95 +/- 8 microm (mean +/- SD) compared with 122 +/- 46 microm of freshly isolated islets. Islet cell loss may be minimized by performing reaggregation in the presence of medium glucose (11 mmol/L) and the GLP-1 analogue Exendin-4. Morphology, cellular composition, and architecture of reaggregated islets were comparable to intact islets. The "hanging drop" culture method allowed us to obtain pseudoislets of standardized size and regular shape, which did not differ from intact islets in terms of cellular composition or architecture. Further investigations are required to minimize cell loss and test in vivo function of transplanted pseudoislets.

  15. Generation of Human Adult Mesenchymal Stromal/Stem Cells Expressing Defined Xenogenic Vascular Endothelial Growth Factor Levels by Optimized Transduction and Flow Cytometry Purification

    PubMed Central

    Helmrich, Uta; Marsano, Anna; Melly, Ludovic; Wolff, Thomas; Christ, Liliane; Heberer, Michael; Scherberich, Arnaud; Martin, Ivan

    2012-01-01

    Adult mesenchymal stromal/stem cells (MSCs) are a valuable source of multipotent progenitors for tissue engineering and regenerative medicine, but may require to be genetically modified to widen their efficacy in therapeutic applications. For example, overexpression of the angiogenic factor vascular endothelial growth factor (VEGF) at controlled levels is an attractive strategy to overcome the crucial bottleneck of graft vascularization and to avoid aberrant vascular growth. Since the regenerative potential of MSCs is rapidly lost during in vitro expansion, we sought to develop an optimized technique to achieve high-efficiency retroviral vector transduction of MSCs derived from both adipose tissue (adipose stromal cells, ASCs) or bone marrow (BMSCs) and rapidly select cells expressing desired levels of VEGF with minimal in vitro expansion. The proliferative peak of freshly isolated human ASCs and BMSCs was reached 4 and 6 days after plating, respectively. By performing retroviral vector transduction at this time point, >90% efficiency was routinely achieved before the first passage. MSCs were transduced with vectors expressing rat VEGF164 quantitatively linked to a syngenic cell surface marker (truncated rat CD8). Retroviral transduction and VEGF expression did not affect MSC phenotype nor impair their in vitro proliferation and differentiation potential. Transgene expression was also maintained during in vitro differentiation. Furthermore, three subpopulations of transduced BMSCs homogeneously producing specific low, medium, and high VEGF doses could be prospectively isolated by flow cytometry based on the intensity of their CD8 expression already at the first passage. In conclusion, this optimized platform allowed the generation of populations of genetically modified MSCs, expressing specific levels of a therapeutic transgene, already at the first passage, thereby minimizing in vitro expansion and loss of regenerative potential. PMID:22070632

  16. [Laser physics].

    PubMed

    Banús Gassol, J M

    2008-11-01

    The commission of this article plunged me into doubt. First I should confess that I don't find excuse to escape this part if somebody wants to minimally deepen in the knowledge of the biological effects of this energy source. Secondly, when we talk about results, we use terms made and defined by Physics. Often we have polemics about results, and what really happens is that we don't reach agreements because we refer to different terms to explain the same observation; in conclusion we cannot understand each other because we do not know the adequate terms; for example, hypoxemia as oxygen deficit, which is true in an anemic patient as well as in a low oxygen saturation rate. In consequence, a good review of these concepts seems necessary to me. The third reason is the confusion that exists in our environment, I think sometimes of interest, about properties and effects of different types of laser. Only a minimal knowledge of physics will help us to state the scientific basis for understanding. The problems, nevertheless, accumulate due to the fact that the universe to which this article is directed is formed by urologists. What Physics education should we suppose they have? Superficial? Medium? Is it a collective with a uniform knowledge, being it whatever it is? The implication is clear. The article depth will depend on the answers to these questions. Nevertheless, the aim of the authors is to give a base enough to know what the laser is and how it acts. For that, the answer I gave to my questions is that the reader should understand the article and have enough base for, at least, reading critically the articles about laser published in urological journals.

  17. The Association between Rural Residence and the Use, Type, and Quality of Depression Care

    ERIC Educational Resources Information Center

    Fortney, John C.; Harman, Jeffrey S.; Xu, Stanley; Dong, Fran

    2010-01-01

    Objective: To assess the association between rurality and depression care. Methods: Data were extracted for 10,319 individuals with self-reported depression in the Medical Expenditure Panel Survey. Pharmacotherapy was defined as an antidepressant prescription fill, and minimally adequate pharmacotherapy was defined as receipt of at least 4…

  18. Distance majorization and its applications

    PubMed Central

    Chi, Eric C.; Zhou, Hua; Lange, Kenneth

    2014-01-01

    The problem of minimizing a continuously differentiable convex function over an intersection of closed convex sets is ubiquitous in applied mathematics. It is particularly interesting when it is easy to project onto each separate set, but nontrivial to project onto their intersection. Algorithms based on Newton’s method such as the interior point method are viable for small to medium-scale problems. However, modern applications in statistics, engineering, and machine learning are posing problems with potentially tens of thousands of parameters or more. We revisit this convex programming problem and propose an algorithm that scales well with dimensionality. Our proposal is an instance of a sequential unconstrained minimization technique and revolves around three ideas: the majorization-minimization principle, the classical penalty method for constrained optimization, and quasi-Newton acceleration of fixed-point algorithms. The performance of our distance majorization algorithms is illustrated in several applications. PMID:25392563

  19. Cosmological Ohm's law and dynamics of non-minimal electromagnetism

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hollenstein, Lukas; Jain, Rajeev Kumar; Urban, Federico R., E-mail: lukas.hollenstein@cea.fr, E-mail: jain@cp3.dias.sdu.dk, E-mail: furban@ulb.ac.be

    2013-01-01

    The origin of large-scale magnetic fields in cosmic structures and the intergalactic medium is still poorly understood. We explore the effects of non-minimal couplings of electromagnetism on the cosmological evolution of currents and magnetic fields. In this context, we revisit the mildly non-linear plasma dynamics around recombination that are known to generate weak magnetic fields. We use the covariant approach to obtain a fully general and non-linear evolution equation for the plasma currents and derive a generalised Ohm law valid on large scales as well as in the presence of non-minimal couplings to cosmological (pseudo-)scalar fields. Due to the sizeablemore » conductivity of the plasma and the stringent observational bounds on such couplings, we conclude that modifications of the standard (adiabatic) evolution of magnetic fields are severely limited in these scenarios. Even at scales well beyond a Mpc, any departure from flux freezing behaviour is inhibited.« less

  20. Laser amplifier and method

    DOEpatents

    Backus, S.; Kapteyn, H.C.; Murnane, M.M.

    1997-07-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethrough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate. 7 figs.

  1. Laser amplifier and method

    DOEpatents

    Backus, Sterling; Kapteyn, Henry C.; Murnane, Margaret M.

    1997-01-01

    Laser amplifiers and methods for amplifying a laser beam are disclosed. A representative embodiment of the amplifier comprises first and second curved mirrors, a gain medium, a third mirror, and a mask. The gain medium is situated between the first and second curved mirrors at the focal point of each curved mirror. The first curved mirror directs and focuses a laser beam to pass through the gain medium to the second curved mirror which reflects and recollimates the laser beam. The gain medium amplifies and shapes the laser beam as the laser beam passes therethough. The third mirror reflects the laser beam, reflected from the second curved mirror, so that the laser beam bypasses the gain medium and return to the first curved mirror, thereby completing a cycle of a ring traversed by the laser beam. The mask defines at least one beam-clipping aperture through which the laser beam passes during a cycle. The gain medium is pumped, preferably using a suitable pumping laser. The laser amplifier can be used to increase the energy of continuous-wave or, especially, pulsed laser beams including pulses of femtosecond duration and relatively high pulse rate.

  2. An improved medium for the anaerobic growth of Paracoccus denitrificans Pd1222

    PubMed Central

    Hahnke, Stefanie M.; Moosmann, Philipp; Erb, Tobias J.; Strous, Marc

    2014-01-01

    Paracoccus denitrificans is a well studied model organism with respect to its aerobic and anaerobic respiratory enzymes. However, until now, the growth medium for this organism has not been optimized for anaerobic growth. In particular, the requirements of P. denitrificans for trace elements (TEs) are not well known. In the present study we aimed to improve growth rates of P. denitrificans Pd1222 on a defined medium under anoxic conditions. We designed media containing different combinations of TEs at various concentrations, and tested their performance against previously reported media. Our results suggest that growth rate and yield depend on the availability and concentration of TEs in the medium. A chelated TE solution was more suitable than an acidified TE solution. Highest growth rates were achieved with medium comprising the TEs iron, manganese, molybdenum, copper and zinc ranging from 0.1 to 9 μM. On this medium, P. denitrificans Pd1222 grew with a generation time of 4.4 h under anoxic conditions and 2.8 h under oxic conditions. Diauxic growth was clearly shown with respect to nitrate and nitrite reduction under anoxic conditions. PMID:24550891

  3. An improved medium for the anaerobic growth of Paracoccus denitrificans Pd1222.

    PubMed

    Hahnke, Stefanie M; Moosmann, Philipp; Erb, Tobias J; Strous, Marc

    2014-01-01

    Paracoccus denitrificans is a well studied model organism with respect to its aerobic and anaerobic respiratory enzymes. However, until now, the growth medium for this organism has not been optimized for anaerobic growth. In particular, the requirements of P. denitrificans for trace elements (TEs) are not well known. In the present study we aimed to improve growth rates of P. denitrificans Pd1222 on a defined medium under anoxic conditions. We designed media containing different combinations of TEs at various concentrations, and tested their performance against previously reported media. Our results suggest that growth rate and yield depend on the availability and concentration of TEs in the medium. A chelated TE solution was more suitable than an acidified TE solution. Highest growth rates were achieved with medium comprising the TEs iron, manganese, molybdenum, copper and zinc ranging from 0.1 to 9 μM. On this medium, P. denitrificans Pd1222 grew with a generation time of 4.4 h under anoxic conditions and 2.8 h under oxic conditions. Diauxic growth was clearly shown with respect to nitrate and nitrite reduction under anoxic conditions.

  4. Effect of Calcium in Assay Medium on D Value of Bacillus stearothermophilus ATCC 7953 Spores

    PubMed Central

    Sasaki, Koichi; Shintani, Hideharu; Itoh, Junpei; Kamogawa, Takuji; Kajihara, Yousei

    2000-01-01

    The D value of commercial biological indicator spore strips using Bacillus stearothermophilus ATCC 7953 was increased by higher calcium concentrations in assay media. The calcium concentration in assay media varied among the manufacturers. The calcium concentration in assay media is an important factor to consider to minimize the variation of D value. PMID:11097939

  5. Waste Minimization in Circuit Board Manufacturing by PARMOD(TM) Technology

    DTIC Science & Technology

    1998-06-24

    a foil package in air or in a plastic syringe. Thermogravimetric Analysis (TGA) Ink samples were evaluated using thermogravimetric analysis in...DTA Differential Thermal Analysis FEP Fluorinated Ethylene Propylene (Teflon®) FTIR Fourier Transform Infrared spectroscopy MOD Metallo-Organic...Decomposition ROM Reactive Organic Medium SEM Scanning Electron Microscopy TGA Thermal Gravimetry Analysis Torr Unit of pressure (one mm mercury

  6. Effects of culture conditions on the fermentation of xylose to ethanol by Candida shehatae

    Treesearch

    T. W. Jeffries

    1985-01-01

    This research examined four factors on the fermentation of xylose by Candida shehatae, and the following conclusions were reached: (1) A minimal medium is effective for producing ethanol. (2) Peptone and casamino acids stimulate ethanol production. (3) Aeration is important in obtaining good ethanol production rates and yields. (4) The maximal rate of ethanol...

  7. A Comparison of the Costs and Benefits of Bacterial Gene Expression

    DOE PAGES

    Price, Morgan N.; Wetmore, Kelly M.; Deutschbauer, Adam M.; ...

    2016-10-06

    In order to study how a bacterium allocates its resources, we compared the costs and benefits of most (86%) of the proteins in Escherichia coli K-12 during growth in minimal glucose medium. The cost or investment in each protein was estimated from ribosomal profiling data, and the benefit of each protein was measured by assaying a library of transposon mutants. We found that proteins that are important for fitness are usually highly expressed, and 95% of these proteins are expressed at above 13 parts per million (ppm). Conversely, proteins that do not measurably benefit the host (with a benefit ofmore » less than 5% per generation) tend to be weakly expressed, with a median expression of 13 ppm. In aggregate, genes with no detectable benefit account for 31% of protein production, or about 22% if we correct for genetic redundancy. Though some of the apparently unnecessary expression could have subtle benefits in minimal glucose medium, the majority of the burden is due to genes that are important in other conditions. We propose that at least 13% of the cell's protein is on standby in case conditions change.« less

  8. Immobilization of Cr(VI) and Its Reduction to Cr(III) Phosphate by Granular Biofilms Comprising a Mixture of Microbes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nancharaiah, Y.V.; Francis, A.; Dodge, C.

    2010-04-01

    We assessed the potential of mixed microbial consortia, in the form of granular biofilms, to reduce chromate and remove it from synthetic minimal medium. In batch experiments, acetate-fed granular biofilms incubated aerobically reduced 0.2 mM Cr(VI) from a minimal medium at 0.15 mM day-1 g-1, with reduction of 0.17 mM day-1 g-1 under anaerobic conditions. There was negligible removal of Cr(VI) (i) without granular biofilms, (ii) with lyophilized granular biofilms, and (iii) with granules in the absence of an electron donor. Analyses by X-ray absorption near edge spectroscopy (XANES) of the granular biofilms revealed the conversion of soluble Cr(VI) tomore » Cr(III). Extended X-ray absorption fine-structure (EXAFS) analysis of the Cr-laden granular biofilms demonstrated similarity to Cr(III) phosphate, indicating that Cr(III) was immobilized with phosphate on the biomass subsequent to microbial reduction. The sustained reduction of Cr(VI) by granular biofilms was confirmed in fed-batch experiments. Our study demonstrates the promise of granular-biofilm-based systems in treating Cr(VI)-containing effluents and wastewater.« less

  9. Three-dimensional CT Venography: A Diagnostic Modality for the Preoperative Assessment of Patients with Varicose Veins

    PubMed Central

    Sato, Katsutoshi; Orihashi, Kazumasa; Takahashi, Shinya; Takasaki, Taiichi; Kurosaki, Tatsuya; Imai, Katsuhiko; Ishifuro, Minoru; Sueda, Taijiro

    2011-01-01

    Objective: We preoperatively assessed varicose veins by means of computed tomography (CT) with contrast injection in the veins of the lower extremity (CT venography). This paper reports the procedures, results and implications of CT venography from the surgical aspect. Methods: A total of 48 legs in 39 patients were examined. Contrast medium was diluted ten-fold and injected into the lower extremity veins, often using a dual route of injection. The images were reconstructed with the volume-rendering method. Results: CT venography clearly visualized the veins with a small amount of contrast medium and facilitated the identification of anatomy that was not suitable for passing the stripper. In addition, CT venography helped identify unusual types of varicose veins or uncommon sites of inflow of small saphenous veins. Such information was helpful for avoiding unexpected vascular injury or for minimizing skin incision. Dual-route injection was beneficial to minimize the blind zones. Doppler ultrasound could be more focused on hemodynamic assessment and determination of incision sites. Conclusions: CT Venography is feasible in all cases of varicose veins. When performed in conjunction with ultrasonography, it appears to facilitate the safe and efficient treatment of various types of varicose veins. PMID:23555458

  10. Degradation of TCE using sequential anaerobic biofilm and aerobic immobilized bed reactor

    NASA Technical Reports Server (NTRS)

    Chapatwala, Kirit D.; Babu, G. R. V.; Baresi, Larry; Trunzo, Richard M.

    1995-01-01

    Bacteria capable of degrading trichloroethylene (TCE) were isolated from contaminated wastewaters and soil sites. The aerobic cultures were identified as Pseudomonas aeruginosa (four species) and Pseudomonas fluorescens. The optimal conditions for the growth of aerobic cultures were determined. The minimal inhibitory concentration values of TCE for Pseudomonas sps. were also determined. The aerobic cells were immobilized in calcium alginate in the form of beads. Degradation of TCE by the anaerobic and dichloroethylene (DCE) by aerobic cultures was studied using dual reactors - anaerobic biofilm and aerobic immobilized bed reactor. The minimal mineral salt (MMS) medium saturated with TCE was pumped at the rate of 1 ml per hour into the anaerobic reactor. The MMS medium saturated with DCE and supplemented with xylenes and toluene (3 ppm each) was pumped at the rate of 1 ml per hour into the fluidized air-uplift-type reactor containing the immobilized aerobic cells. The concentrations of TCE and DCE and the metabolites formed during their degradation by the anaerobic and aerobic cultures were monitored by GC. The preliminary study suggests that the anaerobic and aerobic cultures of our isolates can degrade TCE and DCE.

  11. Informing cancer patient based on his type of personality: the suspicious (paranoid) patient.

    PubMed

    Kallergis, G

    2013-01-01

    Imparting bad news had always been an unpleasant task for the physician, as shown from ancient years to our days. In the healthcare sector and as far as the cancer patient is concerned, the imparting of bad news is performed by the patient's doctor within a therapeutic relationship of course. The fundamental question is how a therapist could tailor the information to any patient and if "Is it possible to determine who should be told what, when and how ?". The aim of this paper was to describe the suspicious character or type of personality thoroughly so that any physician can make a diagnosis and tailor the information strategy to the patient's needs. As method of research was used the qualitative method through groups with doctors and nurses, while research within groups lasted for 5 years. The degree of informing of the suspicious personality in the range "minimal - small - medium - large - very large" is : the degree of denial varies between large and very large. The degree of informing varies between medium and small and sometimes minimal. Informing the Family: The hardest family to deal with. Pay attention to litigious mania. Avoid confrontation or be drawn into agreeing with the family views.

  12. A Comparison of the Costs and Benefits of Bacterial Gene Expression

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Price, Morgan N.; Wetmore, Kelly M.; Deutschbauer, Adam M.

    In order to study how a bacterium allocates its resources, we compared the costs and benefits of most (86%) of the proteins in Escherichia coli K-12 during growth in minimal glucose medium. The cost or investment in each protein was estimated from ribosomal profiling data, and the benefit of each protein was measured by assaying a library of transposon mutants. We found that proteins that are important for fitness are usually highly expressed, and 95% of these proteins are expressed at above 13 parts per million (ppm). Conversely, proteins that do not measurably benefit the host (with a benefit ofmore » less than 5% per generation) tend to be weakly expressed, with a median expression of 13 ppm. In aggregate, genes with no detectable benefit account for 31% of protein production, or about 22% if we correct for genetic redundancy. Though some of the apparently unnecessary expression could have subtle benefits in minimal glucose medium, the majority of the burden is due to genes that are important in other conditions. We propose that at least 13% of the cell's protein is on standby in case conditions change.« less

  13. Establishment of uracil auxotrophic dikaryotic strains of Lentinula edodes by crossbreeding.

    PubMed

    Zhou, Chenli; Xi, Liping; Mao, Wenjun; Wan, Jianing; Li, Yan; Wang, Ying; Bao, Dapeng

    2017-03-01

    The uracil auxotrophic monokaryotic strain 423-9 of Lentinula edodes was crossed with nine monokaryons (cro2-2-9, W66-1, xd2-3-2, QingKe 20A, 241-1-1, 9015-1, L66-2, 241-1-2, and Qing 23A) derived from wild type strains of L. edodes . Nine dikaryotic hybrids were established from these crosses. These hybrids were fruited and 496 single spore isolates were obtained. Among these single spore isolates, 166 were identified as monokaryons under a microscope. We screened these monokaryons on selective medium and obtained 19 uracil auxotrophic monokaryons. By using the Monkaryon-monkaryon crossing method among the uracil auxotrophic monokaryons, 56 uracil auxotrophic dikaryotic strains were established on selective medium. These dikaryotic strains were unable to grow on minimal medium without uracil and exhibited slow growth rates on PDA plates compared to the wild type strain. The uracil auxotrophic dikaryotic strains also showed more vigorous growth on sawdust cultivation medium containing uracil than that without uracil. The fruiting tests showed that they formed normal fruiting bodies on the sawdust medium containing uracil. The results show that the uracil auxotrophic dikaryotic strain of L. edodes could be produced by mating, and will provide a valuable resource for future genetic studies and for spawn protection and identification.

  14. 49 CFR 523.8 - Heavy-duty vocational vehicle.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION VEHICLE CLASSIFICATION § 523.8 Heavy-duty vocational vehicle. Heavy... excluding: (a) Heavy-duty pickup trucks and vans defined in § 523.7; (b) Medium duty passenger vehicles; and...

  15. Hot gas path component cooling system

    DOEpatents

    Lacy, Benjamin Paul; Bunker, Ronald Scott; Itzel, Gary Michael

    2014-02-18

    A cooling system for a hot gas path component is disclosed. The cooling system may include a component layer and a cover layer. The component layer may include a first inner surface and a second outer surface. The second outer surface may define a plurality of channels. The component layer may further define a plurality of passages extending generally between the first inner surface and the second outer surface. Each of the plurality of channels may be fluidly connected to at least one of the plurality of passages. The cover layer may be situated adjacent the second outer surface of the component layer. The plurality of passages may be configured to flow a cooling medium to the plurality of channels and provide impingement cooling to the cover layer. The plurality of channels may be configured to flow cooling medium therethrough, cooling the cover layer.

  16. Clinical competence of Guatemalan and Mexican physicians for family dysfunction management.

    PubMed

    Cabrera-Pivaral, Carlos Enrique; Orozco-Valerio, María de Jesús; Celis-de la Rosa, Alfredo; Covarrubias-Bermúdez, María de Los Ángeles; Zavala-González, Marco Antonio

    2017-01-01

    To evaluate the clinical competence of Mexican and Guatemalan physicians to management the family dysfunction. Cross comparative study in four care units first in Guadalajara, Mexico, and four in Guatemala, Guatemala, based on a purposeful sampling, involving 117 and 100 physicians, respectively. Clinical competence evaluated by validated instrument integrated for 187 items. Non-parametric descriptive and inferential statistical analysis was performed. The percentage of Mexican physicians with high clinical competence was 13.7%, medium 53%, low 24.8% and defined by random 8.5%. For the Guatemalan physicians'14% was high, average 63%, and 23% defined by random. There were no statistically significant differences between healthcare country units, but between the medium of Mexicans (0.55) and Guatemalans (0.55) (p = 0.02). The proportion of the high clinical competency of Mexican physicians' was as Guatemalans.

  17. Application of statistical experimental design for optimisation of bioinsecticides production by sporeless Bacillus thuringiensis strain on cheap medium.

    PubMed

    Ben Khedher, Saoussen; Jaoua, Samir; Zouari, Nabil

    2013-01-01

    In order to overproduce bioinsecticides production by a sporeless Bacillus thuringiensis strain, an optimal composition of a cheap medium was defined using a response surface methodology. In a first step, a Plackett-Burman design used to evaluate the effects of eight medium components on delta-endotoxin production showed that starch, soya bean and sodium chloride exhibited significant effects on bioinsecticides production. In a second step, these parameters were selected for further optimisation by central composite design. The obtained results revealed that the optimum culture medium for delta-endotoxin production consists of 30 g L(-1) starch, 30 g L(-1) soya bean and 9 g L(-1) sodium chloride. When compared to the basal production medium, an improvement in delta-endotoxin production up to 50% was noted. Moreover, relative toxin yield of sporeless Bacillus thuringiensis S22 was improved markedly by using optimised cheap medium (148.5 mg delta-endotoxins per g starch) when compared to the yield obtained in the basal medium (94.46 mg delta-endotoxins per g starch). Therefore, the use of optimised culture cheap medium appeared to be a good alternative for a low cost production of sporeless Bacillus thuringiensis bioinsecticides at industrial scale which is of great importance in practical point of view.

  18. Application of statistical experimental design for optimisation of bioinsecticides production by sporeless Bacillus thuringiensis strain on cheap medium

    PubMed Central

    Ben Khedher, Saoussen; Jaoua, Samir; Zouari, Nabil

    2013-01-01

    In order to overproduce bioinsecticides production by a sporeless Bacillus thuringiensis strain, an optimal composition of a cheap medium was defined using a response surface methodology. In a first step, a Plackett-Burman design used to evaluate the effects of eight medium components on delta-endotoxin production showed that starch, soya bean and sodium chloride exhibited significant effects on bioinsecticides production. In a second step, these parameters were selected for further optimisation by central composite design. The obtained results revealed that the optimum culture medium for delta-endotoxin production consists of 30 g L−1 starch, 30 g L−1 soya bean and 9 g L−1 sodium chloride. When compared to the basal production medium, an improvement in delta-endotoxin production up to 50% was noted. Moreover, relative toxin yield of sporeless Bacillus thuringiensis S22 was improved markedly by using optimised cheap medium (148.5 mg delta-endotoxins per g starch) when compared to the yield obtained in the basal medium (94.46 mg delta-endotoxins per g starch). Therefore, the use of optimised culture cheap medium appeared to be a good alternative for a low cost production of sporeless Bacillus thuringiensis bioinsecticides at industrial scale which is of great importance in practical point of view. PMID:24516462

  19. Apparatus for separating particles utilizing engineered acoustic contrast capture particles

    DOEpatents

    Kaduchak, Gregory; Ward, Michael D

    2014-10-21

    An apparatus for separating particles from a medium includes a capillary defining a flow path therein that is in fluid communication with a medium source. The medium source includes engineered acoustic contrast capture particle having a predetermined acoustic contrast. The apparatus includes a vibration generator that is operable to produce at least one acoustic field within the flow path. The acoustic field produces a force potential minima for positive acoustic contrast particles and a force potential minima for negative acoustic contrast particles in the flow path and drives the engineered acoustic contrast capture particles to either the force potential minima for positive acoustic contrast particles or the force potential minima for negative acoustic contrast particles.

  20. Apparatus for separating particles utilizing engineered acoustic contrast capture particles

    DOEpatents

    Kaduchak, Gregory [Los Alamos, NM; Ward, Michael D [Los Alamos, NM

    2011-12-27

    An apparatus for separating particles from a medium includes a capillary defining a flow path therein that is in fluid communication with a medium source. The medium source includes engineered acoustic contrast capture particle having a predetermined acoustic contrast. The apparatus includes a vibration generator that is operable to produce at least one acoustic field within the flow path. The acoustic field produces a force potential minima for positive acoustic contrast particles and a force potential minima for negative acoustic contrast particles in the flow path and drives the engineered acoustic contrast capture particles to either the force potential minima for positive acoustic contrast particles or the force potential minima for negative acoustic contrast particles.

  1. Side wall cooling for nozzle segments for a gas turbine

    DOEpatents

    Burdgick, Steven Sebastian

    2002-01-01

    A nozzle vane segment includes outer and inner band portions with a vane extending therebetween and defining first and second cavities separated by an impingement plate for flowing cooling medium for impingement cooling of nozzle side walls. The side wall of each nozzle segment has an undercut region. The impingement plate has an inturned flange with a plurality of openings. Cooling inserts or receptacles having an open end are received in the openings and the base and side walls of the receptacles have apertures for receiving cooling medium from the first cavity and directing the cooling medium for impingement cooling of the side wall of the nozzle segment and a portion of the nozzle wall.

  2. Space filling minimal surfaces and sphere packings

    NASA Astrophysics Data System (ADS)

    Elser, Veit

    1994-05-01

    A space filling minimal surface is defined to be any embedded minimal surface without boundary with the property that the area and genus enclosed by any large spherical region scales in proportion to the volume of the region. The triply periodic minimal surfaces are one realization, but not necessarily the only one. By using the genus per unit volume of the surface, a meaningful comparison of surface areas can be made even in cases where there is no unit cell. Of the known periodic minimal surfaces this measure of the surface area is smallest for Schoen's FRD surface. This surface is one of several that is closely related to packings of spheres. Its low area is largely due to the fact that the corresponding sphere packing (fcc) has the maximal kissing number.

  3. Direct Demonstration of the Concept of Unrestricted Effective-Medium Approximation

    NASA Technical Reports Server (NTRS)

    Mishchenko, Michael I.; Dlugach, Zhanna M.; Zakharova, Nadezhda T.

    2014-01-01

    The modified unrestricted effective-medium refractive index is defined as one that yields accurate values of a representative set of far-field scattering characteristics (including the scattering matrix) for an object made of randomly heterogeneous materials. We validate the concept of the modified unrestricted effective-medium refractive index by comparing numerically exact superposition T-matrix results for a spherical host randomly filled with a large number of identical small inclusions and Lorenz-Mie results for a homogeneous spherical counterpart. A remarkable quantitative agreement between the superposition T-matrix and Lorenz-Mie scattering matrices over the entire range of scattering angles demonstrates unequivocally that the modified unrestricted effective-medium refractive index is a sound (albeit still phenomenological) concept provided that the size parameter of the inclusions is sufficiently small and their number is sufficiently large. Furthermore, it appears that in cases when the concept of the modified unrestricted effective-medium refractive index works, its actual value is close to that predicted by the Maxwell-Garnett mixing rule.

  4. Solid state laser

    NASA Technical Reports Server (NTRS)

    Rines, Glen A. (Inventor); Moulton, Peter F. (Inventor); Harrison, James (Inventor)

    1993-01-01

    A wavelength-tunable, injection-seeded, dispersion-compensated, dispersively-pumped solid state laser includes a lasing medium; a highly reflective mirror; an output coupler; at least one isosceles Brewster prism oriented to the minimum deviation angle between the medium and the mirror for directing light of different wavelengths along different paths; means for varying the angle of the highly reflective mirror relative to the light from at least one Brewster angle for selecting a predetermined laser operating wavelength; a dispersion compensation apparatus associated with the lasing medium; a laser injection seeding port disposed between the dispersion compensation apparatus and one of the mirror and coupler and including a reflective surface at an acute non-Brewster angle to the laser beam for introducing a seed input; a dispersion compensation apparatus associated with the laser medium including opposite chirality optical elements; the lasing medium including a pump surface disposed at an acute angle to the laser beam to define a discrete path for the pumping laser beam separate from the pumped laser beam.

  5. Photon path distribution and optical responses of turbid media: theoretical analysis based on the microscopic Beer-Lambert law.

    PubMed

    Tsuchiya, Y

    2001-08-01

    A concise theoretical treatment has been developed to describe the optical responses of a highly scattering inhomogeneous medium using functions of the photon path distribution (PPD). The treatment is based on the microscopic Beer-Lambert law and has been found to yield a complete set of optical responses by time- and frequency-domain measurements. The PPD is defined for possible photons having a total zigzag pathlength of l between the points of light input and detection. Such a distribution is independent of the absorption properties of the medium and can be uniquely determined for the medium under quantification. Therefore, the PPD can be calculated with an imaginary reference medium having the same optical properties as the medium under quantification except for the absence of absorption. One of the advantages of this method is that the optical responses, the total attenuation, the mean pathlength, etc are expressed by functions of the PPD and the absorption distribution.

  6. Modelling rating curves using remotely sensed LiDAR data

    USGS Publications Warehouse

    Nathanson, Marcus; Kean, Jason W.; Grabs, Thomas J.; Seibert, Jan; Laudon, Hjalmar; Lyon, Steve W.

    2012-01-01

    Accurate stream discharge measurements are important for many hydrological studies. In remote locations, however, it is often difficult to obtain stream flow information because of the difficulty in making the discharge measurements necessary to define stage-discharge relationships (rating curves). This study investigates the feasibility of defining rating curves by using a fluid mechanics-based model constrained with topographic data from an airborne LiDAR scanning. The study was carried out for an 8m-wide channel in the boreal landscape of northern Sweden. LiDAR data were used to define channel geometry above a low flow water surface along the 90-m surveyed reach. The channel topography below the water surface was estimated using the simple assumption of a flat streambed. The roughness for the modelled reach was back calculated from a single measurment of discharge. The topographic and roughness information was then used to model a rating curve. To isolate the potential influence of the flat bed assumption, a 'hybrid model' rating curve was developed on the basis of data combined from the LiDAR scan and a detailed ground survey. Whereas this hybrid model rating curve was in agreement with the direct measurements of discharge, the LiDAR model rating curve was equally in agreement with the medium and high flow measurements based on confidence intervals calculated from the direct measurements. The discrepancy between the LiDAR model rating curve and the low flow measurements was likely due to reduced roughness associated with unresolved submerged bed topography. Scanning during periods of low flow can help minimize this deficiency. These results suggest that combined ground surveys and LiDAR scans or multifrequency LiDAR scans that see 'below' the water surface (bathymetric LiDAR) could be useful in generating data needed to run such a fluid mechanics-based model. This opens a realm of possibility to remotely sense and monitor stream flows in channels in remote locations.

  7. On-off intermittency and intermingledlike basins in a granular medium.

    PubMed

    Schmick, Malte; Goles, Eric; Markus, Mario

    2002-12-01

    Molecular dynamic simulations of a medium consisting of disks in a periodically tilted box yield two dynamic modes differing considerably in the total potential and kinetic energies of the disks. Depending on parameters, these modes display the following features: (i) hysteresis (coexistence of the two modes in phase space); (ii) intermingledlike basins of attraction (uncertainty exponent indistinguishable from zero); (iii) two-state on-off intermittency; and (iv) bimodal velocity distributions. Bifurcations are defined by a cross-shaped phase diagram.

  8. Analysis of operational requirements for medium density air transportation, volume 2

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The medium density air travel market is examined and defined in terms of numbers of people transported per route per day and frequency of service. The operational characteristics for aircraft to serve this market are determined and a basepoint aircraft is designed from which tradeoff studies and parametric variations can be conducted. The impact of the operational characteristics on the air travel system is evaluated along with the economic viability of the study aircraft. Research and technology programs for future study consideration are identified.

  9. Identification of Moraxella bovis by qualitative genetic transformation and nutritional assays.

    PubMed Central

    Juni, E; Heym, G A; Newcomb, R D

    1988-01-01

    Strains of Moraxella bovis were identified definitively through the combined use of a qualitative genetic transformation assay and determination of the ability of the organism under examination to grow in a defined medium (medium MB). Except for weak transformation by DNA from strains of M. lacunata, M. nonliquefaciens, and M. (Branhamella) ovis, DNA samples from all other members of the genus Moraxella failed to transform either of the two M. bovis auxotrophs used in this study. Images PMID:3389822

  10. On the minimal risk threshold in research with children.

    PubMed

    Binik, Ariella

    2014-01-01

    To protect children in research, procedures that are not administered in the medical interests of a child must be restricted. The risk threshold for these procedures is generally measured according to the concept of minimal risk. Minimal risk is often defined according to the risks of "daily life." But it is not clear whose daily life should serve as the baseline; that is, it is not clear to whom minimal risk should refer. Commentators in research ethics often argue that "minimal risk" should refer to healthy children or the subjects of the research. I argue that neither of these interpretations is successful. I propose a new interpretation in which minimal risk refers to children who are not unduly burdened by their daily lives. I argue that children are not unduly burdened when they fare well, and I defend a substantive goods account of children's welfare.

  11. Application of a cell-once-through perfusion strategy for production of recombinant antibody from rCHO cells in a Centritech Lab II centrifuge system.

    PubMed

    Kim, Byoung Jin; Chang, Ho Nam; Oh, Duk Jae

    2007-01-01

    Based upon the results of scale-down intermittent perfusion processes, a cell-once-through (COT) perfusion concept was applied to a dual bioreactor system coupled to a Centritech Lab II centrifuge for culture of recombinant Chinese hamster ovary (rCHO) cells for monoclonal antibody production. In this new culture mode, i.e., the COT perfusion process, total spent medium was transferred to the centrifuge and a fixed percentage was removed. Approximately 99% of the viable cells are transferred to another bioreactor filled with fresh medium by single operation of the Centritech Lab II centrifuge system for about 30 min. Accordingly, a significant reduction of the cell-passage frequency to the centrifuge led to minimization of cell damage caused by mechanical shear stress, oxygen limitation, nutrient limitation, and low temperature outside the bioreactor. The effects of culture temperature shift and fortified medium on cell growth and recombinant antibody production in the COT perfusion process were investigated. Although the suppressive effects of low culture temperature on cell growth led to a loss of stability in a long-term COT perfusion culture system, the average antibody concentration at 33 degrees C was 157.8 mg/L, approximately 2.4-fold higher than that at 37 degrees C. By the use of a fortified medium at 37 degrees C, rCHO cells were maintained at high density above 1.2 x 10(7) cells/mL, and antibody was produced continuously in a range of 260-280 mg/L in a stable long-term COT perfusion culture. The proposed new culture mode, the COT perfusion approach, guarantees the recovery of rCHO cells damaged by lowered temperature or high lactate and ammonium concentration. It will be an attractive choice for minimization of cell damage and stable long-term antibody production with high cell density.

  12. Hybrid Pareto artificial bee colony algorithm for multi-objective single machine group scheduling problem with sequence-dependent setup times and learning effects.

    PubMed

    Yue, Lei; Guan, Zailin; Saif, Ullah; Zhang, Fei; Wang, Hao

    2016-01-01

    Group scheduling is significant for efficient and cost effective production system. However, there exist setup times between the groups, which require to decrease it by sequencing groups in an efficient way. Current research is focused on a sequence dependent group scheduling problem with an aim to minimize the makespan in addition to minimize the total weighted tardiness simultaneously. In most of the production scheduling problems, the processing time of jobs is assumed as fixed. However, the actual processing time of jobs may be reduced due to "learning effect". The integration of sequence dependent group scheduling problem with learning effects has been rarely considered in literature. Therefore, current research considers a single machine group scheduling problem with sequence dependent setup times and learning effects simultaneously. A novel hybrid Pareto artificial bee colony algorithm (HPABC) with some steps of genetic algorithm is proposed for current problem to get Pareto solutions. Furthermore, five different sizes of test problems (small, small medium, medium, large medium, large) are tested using proposed HPABC. Taguchi method is used to tune the effective parameters of the proposed HPABC for each problem category. The performance of HPABC is compared with three famous multi objective optimization algorithms, improved strength Pareto evolutionary algorithm (SPEA2), non-dominated sorting genetic algorithm II (NSGAII) and particle swarm optimization algorithm (PSO). Results indicate that HPABC outperforms SPEA2, NSGAII and PSO and gives better Pareto optimal solutions in terms of diversity and quality for almost all the instances of the different sizes of problems.

  13. A novel solid dosage form of rifampicin and isoniazid with improved functionality.

    PubMed

    Gohel, Mukesh C; Sarvaiya, Krishnakant G

    2007-08-24

    The aim of the present investigation was to develop a novel dosage form of rifampicin and isoniazid to minimize degradation of rifampicin in acidic medium and to modulate the release of rifampicin in the stomach and isoniazid in the intestine. Gastroretentive tablets of rifampicin (150 mg) were prepared by the wet granulation method using hydroxypropyl methylcellulose, calcium carbonate, and polyethylene glycol 4000. The granules and tablets of rifampicin were characterized. Hard gelatin capsules (size 4) containing a compacted mass of isoniazid (150 mg) and dicalcium phosphate (75 mg) were enteric coated. Two tablets of rifampicin and 1 capsule (size 4) of isoniazid were put into a hard gelatin capsule (size 00). The in vitro drug release and in vitro drug degradation studies were performed. Rifampicin was released over 4 hours by zero-order kinetics from the novel dosage form. More than 90% of isoniazid was released in alkaline medium in 30 minutes. The results of dissolution studies with the US Pharmacopeia XXIII method revealed that a substantial amount of rifampicin was degraded from the immediate release capsule containing rifampicin and isoniazid powder owing to drug accumulation in the dissolution vessel and also to the presence of isoniazid. The degradation of rifampicin to 3-formyl rifampicin SV (3FRSV) was arrested (3.6%-4.8% degradation of rifampicin at 4 hours) because of the minimization of physical contact between the 2 drugs and controlled release of rifampicin in acidic medium in the modified Rossett-Rice apparatus. This study concludes that the problem of rifampicin degradation can be alleviated to a certain extent by this novel dosage form.

  14. Representing Lumped Markov Chains by Minimal Polynomials over Field GF(q)

    NASA Astrophysics Data System (ADS)

    Zakharov, V. M.; Shalagin, S. V.; Eminov, B. F.

    2018-05-01

    A method has been proposed to represent lumped Markov chains by minimal polynomials over a finite field. The accuracy of representing lumped stochastic matrices, the law of lumped Markov chains depends linearly on the minimum degree of polynomials over field GF(q). The method allows constructing the realizations of lumped Markov chains on linear shift registers with a pre-defined “linear complexity”.

  15. Minimally invasive thyroid nodulectomy reduces post-operative hypothyroidism when compared with thyroid lobectomy.

    PubMed

    Sarkis, Leba M; Norlen, Olov; Sywak, Mark; Delbridge, Leigh

    2017-05-01

    It has been a long-standing surgical tenet that the minimum surgical procedure for a single thyroid nodule is lobectomy. Such an approach, however, has been associated with a significant incidence of post-operative hypothyroidism with patients becoming medication dependent for life. Thermal sealing devices have enabled local nodule excision to be undertaken safely with preservation of more residual thyroid mass. The aim of this study was to determine if this approach was associated with a reduction in post-operative hypothyroidism. This is a retrospective cohort study comprising 351 patients treated between January 2010 and December 2012. Patients were assessed at 6-8-week review. Subclinical hypothyroidism was defined as a thyroid-stimulating hormone (TSH) >4.5 mIU/L, with clinical hypothyroidism defined as both an elevated TSH and presence of clinical symptoms requiring thyroxine replacement. One hundred and ninety patients underwent open thyroid lobectomy, 86 a minimally invasive thyroid lobectomy and 75 a minimally invasive nodulectomy. There was no difference in post-operative hypothyroidism after lobectomy whether by the open (22.1%) or minimally invasive (22.1%) technique. However, after minimally invasive nodulectomy, post-operative hypothyroidism was less than one quarter (5.3%) of that following lobectomy overall (22.1%, P < 0.01). There were no differences in post-operative complications between any of the groups. Minimally invasive local nodule excision can be performed safely, with the potential for significantly reducing the rate of post-operative hypothyroidism. As such, the procedure should be considered for appropriately selected patients. © 2014 Royal Australasian College of Surgeons.

  16. Effect of gamma irradiation on microbial quality of minimally processed carrot and lettuce: A case study in Greater Accra region of Ghana

    NASA Astrophysics Data System (ADS)

    Frimpong, G. K.; Kottoh, I. D.; Ofosu, D. O.; Larbi, D.

    2015-05-01

    The effect of ionizing radiation on the microbiological quality on minimally processed carrot and lettuce was studied. The aim was to investigate the effect of irradiation as a sanitizing agent on the bacteriological quality of some raw eaten salad vegetables obtained from retailers in Accra, Ghana. Minimally processed carrot and lettuce were analysed for total viable count, total coliform count and pathogenic organisms. The samples collected were treated and analysed for a 15 day period. The total viable count for carrot ranged from 1.49 to 14.01 log10 cfu/10 g while that of lettuce was 0.70 to 8.5 7 log10 cfu/10 g. It was also observed that total coliform count for carrot was 1.46-7.53 log10 cfu/10 g and 0.14-7.35 log10 cfu/10 g for lettuce. The predominant pathogenic organisms identified were Bacillus cereus, Cronobacter sakazakii, Staphylococcus aureus, and Klebsiella spp. It was concluded that 2 kGy was most effective for medium dose treatment of minimally processed carrot and lettuce.

  17. Short-Term and Long-Term Survival and Virulence of Legionella pneumophila in the Defined Freshwater Medium Fraquil.

    PubMed

    Mendis, Nilmini; McBride, Peter; Faucher, Sébastien P

    2015-01-01

    Legionella pneumophila (Lp) is the etiological agent responsible for Legionnaires' disease, a potentially fatal pulmonary infection. Lp lives and multiplies inside protozoa in a variety of natural and man-made water systems prior to human infection. Fraquil, a defined freshwater medium, was used as a highly reproducible medium to study the behaviour of Lp in water. Adopting a reductionist approach, Fraquil was used to study the impact of temperature, pH and trace metal levels on the survival and subsequent intracellular multiplication of Lp in Acanthamoeba castellanii, a freshwater protozoan and a natural host of Legionella. We show that temperature has a significant impact on the short- and long-term survival of Lp, but that the bacterium retains intracellular multiplication potential for over six months in Fraquil. Moreover, incubation in Fraquil at pH 4.0 resulted in a rapid decline in colony forming units, but was not detrimental to intracellular multiplication. In contrast, variations in trace metal concentrations had no impact on either survival or intracellular multiplication in amoeba. Our data show that Lp is a resilient bacterium in the water environment, remaining infectious to host cells after six months under the nutrient-deprived conditions of Fraquil.

  18. Characterization of Canine Adipose-Derived Mesenchymal Stromal/Stem Cells in Serum-Free Medium.

    PubMed

    Liu, Zhuoming; Screven, Rudell; Boxer, Lynne; Myers, Michael J; Devireddy, Lax R

    2018-06-20

    In this article, we report on the development of a defined serum-free medium capable of supporting the culture expansion of mesenchymal stromal/stem cells (MSCs) from canine adipose tissue (canine Ad-MSCs). The potential benefits of serum-free media can only be utilized if cells cultured in serum-free media maintain the same functional characteristics as cells cultured in serum-containing media. Therefore, we analyze the characteristics of canine Ad-MSCs cultured in this serum-free medium or in serum-containing medium through evaluation of growth kinetics, clonogenic capacity, senescence, and differentiation capacity. Both, serum-containing medium and our serum-free medium, supported efficient growth and colony formation of canine Ad-MSCs. In addition, canine Ad-MSCs cultured in both media demonstrated similar viability after freeze/thaw, similar cell surface marker expression, and were capable of trilineage differentiation. While canine Ad-MSCs cultured in both media were generally similar, under the conditions of our study, canine Ad-MSCs cultured in serum-free medium demonstrated a shorter lag phase and higher colony-forming capacity, accelerated population doubling, maintained multipotentiality at higher passage numbers, and underwent senescence at higher passage numbers compared to canine Ad-MSCs cultured in conventional serum-containing medium. These results suggest that canine Ad-MSCs cultured in serum-free medium retain the basic characteristics associated with canine Ad-MSCs cultured in serum-containing medium, although some differences in growth kinetics were observed.

  19. Economic impact of minimally invasive lumbar surgery.

    PubMed

    Hofstetter, Christoph P; Hofer, Anna S; Wang, Michael Y

    2015-03-18

    Cost effectiveness has been demonstrated for traditional lumbar discectomy, lumbar laminectomy as well as for instrumented and noninstrumented arthrodesis. While emerging evidence suggests that minimally invasive spine surgery reduces morbidity, duration of hospitalization, and accelerates return to activites of daily living, data regarding cost effectiveness of these novel techniques is limited. The current study analyzes all available data on minimally invasive techniques for lumbar discectomy, decompression, short-segment fusion and deformity surgery. In general, minimally invasive spine procedures appear to hold promise in quicker patient recovery times and earlier return to work. Thus, minimally invasive lumbar spine surgery appears to have the potential to be a cost-effective intervention. Moreover, novel less invasive procedures are less destabilizing and may therefore be utilized in certain indications that traditionally required arthrodesis procedures. However, there is a lack of studies analyzing the economic impact of minimally invasive spine surgery. Future studies are necessary to confirm the durability and further define indications for minimally invasive lumbar spine procedures.

  20. A comparative study on stress and compliance based structural topology optimization

    NASA Astrophysics Data System (ADS)

    Hailu Shimels, G.; Dereje Engida, W.; Fakhruldin Mohd, H.

    2017-10-01

    Most of structural topology optimization problems have been formulated and solved to either minimize compliance or weight of a structure under volume or stress constraints, respectively. Even if, a lot of researches are conducted on these two formulation techniques separately, there is no clear comparative study between the two approaches. This paper intends to compare these formulation techniques, so that an end user or designer can choose the best one based on the problems they have. Benchmark problems under the same boundary and loading conditions are defined, solved and results are compared based on these formulations. Simulation results shows that the two formulation techniques are dependent on the type of loading and boundary conditions defined. Maximum stress induced in the design domain is higher when the design domains are formulated using compliance based formulations. Optimal layouts from compliance minimization formulation has complex layout than stress based ones which may lead the manufacturing of the optimal layouts to be challenging. Optimal layouts from compliance based formulations are dependent on the material to be distributed. On the other hand, optimal layouts from stress based formulation are dependent on the type of material used to define the design domain. High computational time for stress based topology optimization is still a challenge because of the definition of stress constraints at element level. Results also shows that adjustment of convergence criterions can be an alternative solution to minimize the maximum stress developed in optimal layouts. Therefore, a designer or end user should choose a method of formulation based on the design domain defined and boundary conditions considered.

  1. Equilibrium stability of a cylindrical body subject to the internal structure of the material and inelastic behaviour of the completely compressed matrix

    NASA Astrophysics Data System (ADS)

    Gotsev, D. V.; Perunov, N. S.; Sviridova, E. N.

    2018-03-01

    The mathematical model describing the stress-strain state of a cylindrical body under the uniform radial compression effect is constructed. The model of the material is the porous medium model. The compressed skeleton of the porous medium possesses hardening elastic-plastic properties. Deforming of the porous medium under the specified compressive loads is divided into two stages: elastic deforming of the porous medium and further elastic-plastic deforming of the material with completely compressed matrix. The analytical relations that define the fields of stress and displacement at each stage of the deforming are obtained. The influence of the porosity and other physical, mechanical and geometric parameters of the construction on the size of the plastic zone is evaluated. The question of the ground state equilibrium instability is investigated within the framework of the three-dimensional linearized relationships of the stability theory of deformed bodies.

  2. Clean fuels from bioconversion of solar energy. Annual report, 21 January 1980-20 January 1981

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Feighner, S.D.; Sikka, H.C.

    1981-03-01

    The study seeks to enhance glycolic acid excretion by unicellular algae. The strains of algae selected to evaluate glycolic acid accumulation in culture medium were: Chlorella pyrenoidosa (UTEX 395), Chlamydomonas reinhardtii (UTEX 89), Scenedesmus obliquus (UTEX 393), and Ankistrodesmus braunii (UTEX 245). C. pyrenoidosa and C. reinhardtii, based on the amount of glycolic acid produced, were selected for further study. Initial experiments were conducted to measure the effect of different environmental growth conditions on the rate of glycolic accumulation in defined culture medium. The most pronounced effect on glycolic acid excretion was obtained by varying the concentration of carbon dioxidemore » in air. At 1% CO2 in air, C. pyrenoidosa accumulated 5.2 ppm glycolic acid in culture medium. Neither the pH of the culture medium nor the incubation temperature affected glycolic acid accumulation by growing C. pyrenoidosa cultures.« less

  3. Possibilities of vaccine manufacture in human diploid cell strains with a serum replacement factor.

    PubMed

    Candal, F J; George, V G; Ades, E W

    1991-07-01

    Cell lines MDCK (canine kidney), BGM (Buffalo green monkey kidney) and human embryonic lung fibroblast will support viral growth efficiently in medium without serum. Both MRC-5 and WI-38 cell strains have been approved by the Food and Drug Administration for manufacturing viral vaccines against cytomegalovirus and varicella-zoster virus. In this study we examine these two cell lines and viruses for their ability to grow in medium containing a serum replacement. The serum substitute used is LPSR-1 (low protein serum replacement). Using LPSR-1 in defined medium, we demonstrate multipassage cell growth and viral cultivation and replication equivalent to those obtained in medium containing fetal bovine serum (FBS). Viral growth after complete elimination of FBS varies and depends on cell line and virus. Serum substitutes can eliminate FBS in the viral growth phase of vaccine production and reduce costs.

  4. Analysis of waveguides containing EMCs (electromagnetic conductors) or PEMCs (perfect electromagnetic conductors)

    NASA Astrophysics Data System (ADS)

    Prudêncio, Filipa R.; Matos, Sérgio A.; Paiva, Carlos R.

    2014-11-01

    The concept of a perfect electromagnetic conductor (PEMC) was introduced to generalize and unify two well-known and apparently disjoint concepts in electromagnetics: the perfect electric conductor (PEC) and the perfect magnetic conductor (PMC). Although the PEMC has proven a fertile tool in electromagnetic analyses dealing with new and complex boundaries, its corresponding definition as a medium has, nevertheless, raised several problems. In fact, according to its initial 3D definition, the PEMC cannot be considered a unique and well-defined medium: it leads to extraneous fields without physical meaning. By using a previously published generalization of a PEMC that regards this concept both as a boundary and as a medium - which was dubbed an MIM (Minkowskian isotropic medium) and acts, in practice, as an actual electromagnetic conductor (EMC) - it is herein presented a straightforward analysis of waveguides containing PEMCs that readily and systematically follows from the general framework of waveguides containing EMCs.

  5. Hybridization and breeding of the benomyl resistant mutant, Trichoderma harziantum antagonized to phytopathogenic fungi by protoplast fusion.

    PubMed

    Ogawa, K; Yoshida, N; Gesnara, W; Omumasaba, C A; Chamuswarng, C

    2000-04-01

    A diploid strain obtained from heterokaryons of Trichoderma harzianum by protoplast fusion grew on minimal medium containing 100ppm benomyl. This strain inhibited the growth of the phytopathogenic fungus Fusarium oxysporum f. sp. raphani on paired cultures and also protected against radish yellows and a drop in germination induced by F. oxysporum f. sp. raphani.

  6. Genome Sequence of Halomonas sp. Strain KO116, an Ionic Liquid- Tolerant Marine Bacterium Isolated from a Lignin-Enriched Seawater Microcosm

    DOE PAGES

    O'Dell, Kaela; Woo, Hannah L.; Utturkar, Sagar M.; ...

    2015-05-07

    Halomonas sp. strain KO116 was isolated from Nile Delta Mediterranean Sea surface water enriched with insoluble organosolv lignin. It was further screened for growth on alkali lignin minimal salts medium agar. The strain tolerates the ionic liquid 1-ethyl-3-methylimidazolium acetate. Its complete genome sequence is presented in this report.

  7. Maximising Resource Allocation in the Teaching Laboratory: Understanding Student Evaluations of Teaching Assistants in a Team-Based Teaching Format

    ERIC Educational Resources Information Center

    Nikolic, Sasha; Suesse, Thomas F.; McCarthy, Timothy J.; Goldfinch, Thomas L.

    2017-01-01

    Minimal research papers have investigated the use of student evaluations on the laboratory, a learning medium usually run by teaching assistants with little control of the content, delivery and equipment. Finding the right mix of teaching assistants for the laboratory can be an onerous task due to the many skills required including theoretical and…

  8. Recombinant production, isotope labeling and purification of ENOD40B: a plant peptide hormone.

    PubMed

    Chae, Young Kee; Tonneli, Marco; Markley, John L

    2012-08-01

    The plant peptide hormone ENOD40B was produced in a protein production strain of Escherichia coli harboring an induction controller plasmid (Rosetta(DE3)pLysS) as a His6-tagged ubiquitin fusion protein. The fusion protein product was denatured and refolded as part of the isolation procedure and purified by immobilized metal ion chromatography. The peptide hormone was released from its fusion partner by adding yeast ubiquitin hydrolase (YUH) and subsequently purified by reversed phase chromatography. The purity of the resulting peptide fragment was assayed by MALDITOF mass spectrometry and NMR spectroscopy. The final yields of the target peptide were 7.0 mg per liter of LB medium and 3.4 mg per liter of minimal medium.

  9. ART: Surveying the Local Universe at 2-11 keV

    NASA Technical Reports Server (NTRS)

    O'Dell, S. L.; Ramsey, B. D.; Adams, M. L.; Brandt, W. N.; Bubarev, M. V.; Hassinger, G.; Pravlinski, M.; Predehl, P.; Romaine, S. E.; Swartz, D. A.; hide

    2008-01-01

    The Astronomical Rontgen Telescope (ART) is a medium-energy x-ray telescope system proposed for the Russian-led mission Spectrum Rontgen-Gamma (SRG). Optimized for performance over the 2-11-keV band, ART complements the softer response of the SRG prime instrument-the German eROSITA x-ray telescope system. The anticipated number of ART detections is 50,000-with 1,000 heavily-obscured (N(sub H)> 3x10(exp 23)/sq cm) AGN-in the SRG 4-year all-sky survey, plus a comparable number in deeper wide-field (500 deg(sup 2) total) surveys. ART's surveys will provide a minimally-biased, nearly-complete census of the local Universe in the medium-energy x-ray band (including Fe-K lines), at CCD spectral resolution. During long (approx.100-ks) pointed observations, ART can obtain statistically significant spectral data up to about 15 keY for bright sources and medium-energy x-ray continuum and Fe-K-line spectra of AGN detected with the contemporaneous NuSTAR hard-x-ray mission.

  10. Expression of the Sinorhizobium meliloti small RNA gene mmgR is controlled by the nitrogen source.

    PubMed

    Ceizel Borella, Germán; Lagares, Antonio; Valverde, Claudio

    2016-05-01

    Small non-coding regulatory RNAs (sRNAs) are key players in post-transcriptional regulation of gene expression. Hundreds of sRNAs have been identified in Sinorhizobium meliloti, but their biological function remains unknown for most of them. In this study, we characterized the expression pattern of the gene encoding the 77-nt sRNA MmgR in S. meliloti strain 2011. A chromosomal transcriptional reporter fusion (PmmgR-gfp) showed that the mmgR promoter is active along different stages of the interaction with alfalfa roots. In pure cultures, PmmgR-gfp activity paralleled the sRNA abundance indicating that mmgR expression is primarily controlled at the level of transcriptional initiation. PmmgR-gfp activity was higher during growth in rhizobial defined medium (RDM) than in TY medium. Furthermore, PmmgR-gfp was induced at 60 min after shifting growing cells from TY to RDM medium, i.e. shorter than the cell doubling time. In defined RDM medium containing NO3 (-), both PmmgR-gfp and MmgR level were repressed by the addition of tryptone or single amino acids, suggesting that mmgR expression depends on the cellular nitrogen (N) status. In silico analysis failed to detect conserved motifs upstream the promoter RNA polymerase binding site, but revealed a strongly conserved motif centered at -28 that may be linked to the observed regulatory pattern by the N source. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Growth and survival of cowpea rhizobia in acid, aluminum-rich soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartel, P.G.; Alexander, M.

    1983-01-01

    A study was undertaken to determine whether Al-sensitive cowpea Rhizobium survives in acid, Al-rich soils. The lower pH limit for growth of 20 strains in a defined liquid medium varied from pH 4.2 to less than pH 3.6. The mean lower limit for growth was pH 3.9. Several of the strains clumped in this medium at pH 4.5. Of 11 strains that were tested for tolerance to high levels of Al in a defined liquid medium at pH 4.5, nine tolerated 75 ..mu..M Al, and the other two were sensitive to levels above 15 ..mu..M. Three strains, one Al-tolerant, onemore » Al-sensitive, and one Al-tolerant or Al-sensitive depending on the presence of vitamins in the medium, were selected for studies in Al-rich sterile and nonsterile soils. These rhizobia did not survive in soils of less than pH 4.7 sterilized by /sup 60/Co irradiation. When inoculated into sterile soil at pH 4.7, the consistently sensitive strain initially failed to proliferate and then grew slowly, but populations of the other two rhizobia increased rapidly. No consistent relationship was found between the Al tolerance of these three rhizobia and their growth and survival in four acid, Al-rich soils. The data suggest that Al is of minor importance to growth and survival of cowpea Rhizobium strains in acid soils. 16 references, 4 figures, 1 table.« less

  12. Production of Novel Antibiotics Zeamines through Optimizing Dickeya zeae Fermentation Conditions

    PubMed Central

    Liao, Lisheng; Cheng, Yingying; Liu, Shiyin; Zhou, Jianuan; An, Shuwen; Lv, Mingfa; Chen, Yufan; Gu, Yanfang; Chen, Shaohua; Zhang, Lian-Hui

    2014-01-01

    Dickeya zeae strain EC1 was recently shown to produce a new type of phytotoxins designated as zeamine and zeamine II, which are potent wide-spectrum antibiotics against Gram-positive and Gram-negative bacterial pathogens, suggesting their promising potential as clinical medicines. In this study, the optimized medium composition and culture conditions for biosynthesis of novel antibiotics zeamines have been established by using response surface methodology, largely increasing the yield of zeamines from original about 7.35 µg·mL−1 in minimal medium to about 150 µg·mL−1 in LS5 medium. The study identified the major factors contributing to zeamines production, which include nitrate, sucrose, asparaginate, mineral elements Mg2+ and K+, and optimized amount of phosphate. In addition, the results showed that overexpression of zmsK in D. zeae strain EC1 could further increase zeamines yield to about 180 µg·mL−1 in LS5 medium. The findings from this study could facilitate further characterization and utilization of these two novel antibiotics, and also provide useful clues for understanding the regulatory mechanisms that govern D. zeae virulence. PMID:25541733

  13. Optimization of Culture Medium for the Growth of Candida sp. and Blastobotrys sp. as Starter Culture in Fermentation of Cocoa Beans (Theobroma cacao) Using Response Surface Methodology (RSM).

    PubMed

    Mahazar, N H; Zakuan, Z; Norhayati, H; MeorHussin, A S; Rukayadi, Y

    2017-01-01

    Inoculation of starter culture in cocoa bean fermentation produces consistent, predictable and high quality of fermented cocoa beans. It is important to produce healthy inoculum in cocoa bean fermentation for better fermented products. Inoculum could minimize the length of the lag phase in fermentation. The purpose of this study was to optimize the component of culture medium for the maximum cultivation of Candida sp. and Blastobotrys sp. Molasses and yeast extract were chosen as medium composition and Response Surface Methodology (RSM) was then employed to optimize the molasses and yeast extract. Maximum growth of Candida sp. (7.63 log CFU mL-1) and Blastobotrys sp. (8.30 log CFU mL-1) were obtained from the fermentation. Optimum culture media for the growth of Candida sp., consist of 10% (w/v) molasses and 2% (w/v) yeast extract, while for Blastobotrys sp., were 1.94% (w/v) molasses and 2% (w/v) yeast extract. This study shows that culture medium consists of molasses and yeast extract were able to produce maximum growth of Candida sp. and Blastobotrys sp., as a starter culture for cocoa bean fermentation.

  14. Optimisation of the expression of a Trametes versicolor laccase gene in Pichia pastoris.

    PubMed

    O'Callaghan, J; O'Brien, M M; McClean, K; Dobson, A D W

    2002-08-01

    A cDNA encoding a laccase enzyme was isolated from a Trametes versicolor cDNA library. The gene was subcloned into the Pichia pastoris expression vector pPIC3.5 and transformed into the P. pastoris strains KM71 and GS115. Laccase-secreting transformants were selected by their ability to oxidise the substrate ABTS. No difference in laccase activity was observed between culture supernatants from GS115 (proteolytic) and KM71 (nonproteolytic) strains. The presence of at least 200 microM copper was necessary for optimal laccase activity in the culture supernatants. During growth of P. pastoris on minimal medium the pH of the medium was reduced to <3.0. If alanine was added to the medium the pH reduction was not as pronounced and at alanine concentrations >0.6% w/v the pH was kept constant for >7 days. Cultures in which the pH was maintained by alanine metabolism produced higher levels of laccase activity than those grown in the absence of alanine. This study describes the development of a medium that allows convenient pH control of P. pastoris without the need for continuous neutralisation.

  15. Critical reappraisal of embryo quality as a predictive parameter for pregnancy outcome: a pilot study.

    PubMed

    Campo, R; Binda, M M; Van Kerkhoven, G; Frederickx, V; Serneels, A; Roziers, P; Lopes, A S; Gordts, S; Puttemans, P; Gordts, S

    2010-01-01

    Pilot study to analyse the efficacy and embryo morphology using a new human embryo culture medium (GM501) versus the conventional used medium (ISM1). Over a four-month period, all patients at the Leuven Institute of Fertility and Embryology (LIFE) were -randomly allocated to have their embryos cultured in either the standard sequential culture medium ISM1 (control) or in a new universal medium (GM501) (study group). Primary outcome parameters were clinical pregnancy and live birth rate. The secondary outcome parameter was the correlation of embryo fragmentation rate with pregnancy outcome. We did not observe any differences between the ISM1 control group and GM501 study group with regard to fertilization, pregnancy, implantation rates, ongoing pregnancy, and babies born. The number of embryos with a minimal fragmentation rate (less than 30%) was significantly higher in the GM501 study group. Although a significant higher embryo fragmentation rate was seen in In vitro culture of embryos in GM501, pregnancy outcome results were comparable to those of embryos cultured in ISM1. According to our results the value of embryo morphological criteria as a parameter for pregnancy outcome should be examined and discussed again.

  16. Problems in aerial application : I. - V.

    DOT National Transportation Integrated Search

    1966-06-01

    Airmen who apply insecticides from aircraft may suffer ill-defined effects from continued exposure to insecticide particles suspended in the air medium. The present series of experiments has been designed to study both lethal and sublethal effects re...

  17. Rotary drum separator system

    NASA Technical Reports Server (NTRS)

    Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)

    2009-01-01

    A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.

  18. Purification and Properties of Streptococcal Competence Factor Isolated from Chemically Defined Medium

    PubMed Central

    Leonard, C. Gomez; Cole, Roger M.

    1972-01-01

    A procedure for the isolation and purification of competence factor produced in a defined medium by group H streptococci, strain Challis-6, is presented. Partial characterization and chemical analysis of the product are described. The procedure yields competence factor of high purity, as shown by homogeneity in electrofocusing, by electrophoresis in sodium dodecyl sulfate polyacrylamide gels, and by chemical analysis. The data indicate that competence factor is a small, dialyzable, highly basic compound. It is free from lipids, phosphorus, and carbohydrates, and is colorless and thermoresistant. Its biological activity is destroyed by trypsin but not by deoxyribonuclease, ribonuclease, lipase, or lysozyme. Its high isoelectric point of above pH 11.0 suggests that competence factor may be a protamine or a polymer of basic amino acids. The possibility that a polyamine may be an integral part of the polypeptide molecule has not been excluded. PMID:5018023

  19. Apparatus for impingement cooling a side wall adjacent an undercut region of a turbine nozzle segment

    DOEpatents

    Burdgick, Steven Sebastian

    2002-01-01

    A gas turbine nozzle segment has outer and inner bands and vanes therebetween. Each band includes a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band and inturned flange define with the nozzle wall an undercut region. Slots are formed through the inturned flange along the nozzle side wall. A plate having through-apertures extending between opposite edges thereof is disposed in each slot, the slots and plates being angled such that the cooling medium exiting the apertures in the second cavity lie close to the side wall for focusing and targeting cooling medium onto the side wall.

  20. Establishment of mouse embryonic stem cells from isolated blastomeres and whole embryos using three derivation methods

    PubMed Central

    González, Sheyla; Ibáñez, Elena

    2010-01-01

    Purpose The aim of the present study is to compare three previously described mouse embryonic stem cell derivation methods to evaluate the influence of culture conditions, number of isolated blastomeres and embryonic stage in the derivation process. Methods Three embryonic stem cell derivation methods: standard, pre-adhesion and defined culture medium method, were compared in the derivation from isolated blastomeres and whole embryos at 4- and 8-cell stages. Results A total of 200 embryonic stem cell lines were obtained with an efficiency ranging from 1.9% to 72%. Conclusions Using either isolated blastomeres or whole embryos, the highest rates of mouse embryonic stem cell establishment were achieved with the defined culture medium method and efficiencies increased as development progressed. Using isolated blastomeres, efficiencies increased in parallel to the proportion of the embryo volume used to start the derivation process. PMID:20862536

  1. The Blueprint of a Minimal Cell: MiniBacillus

    PubMed Central

    Reuß, Daniel R.; Commichau, Fabian M.; Gundlach, Jan; Zhu, Bingyao

    2016-01-01

    SUMMARY Bacillus subtilis is one of the best-studied organisms. Due to the broad knowledge and annotation and the well-developed genetic system, this bacterium is an excellent starting point for genome minimization with the aim of constructing a minimal cell. We have analyzed the genome of B. subtilis and selected all genes that are required to allow life in complex medium at 37°C. This selection is based on the known information on essential genes and functions as well as on gene and protein expression data and gene conservation. The list presented here includes 523 and 119 genes coding for proteins and RNAs, respectively. These proteins and RNAs are required for the basic functions of life in information processing (replication and chromosome maintenance, transcription, translation, protein folding, and secretion), metabolism, cell division, and the integrity of the minimal cell. The completeness of the selected metabolic pathways, reactions, and enzymes was verified by the development of a model of metabolism of the minimal cell. A comparison of the MiniBacillus genome to the recently reported designed minimal genome of Mycoplasma mycoides JCVI-syn3.0 indicates excellent agreement in the information-processing pathways, whereas each species has a metabolism that reflects specific evolution and adaptation. The blueprint of MiniBacillus presented here serves as the starting point for a successive reduction of the B. subtilis genome. PMID:27681641

  2. In vitro sensitivity of medically significant Fusarium species to various antimycotics.

    PubMed

    Sekhon, A S; Padhye, A A; Garg, A K; Ahmad, H; Moledina, N

    1994-01-01

    Sixteen isolates belonging to Fusarium chlamydosporum (n = 4), Fusarium equiseti (n = 1), Fusarium moniliforme (n = 2), Fusarium oxysporum (n = 3), Fusarium proliferatum (n = 1), and Fusarium solani (n = 5) were tested against amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, ketoconazole, JAI-amphotericin B (water-soluble compound), hamycin and amphotericin B combined with 5-fluorocytosine, using antibiotic medium M3, high-resolution broth (pH 7.1), Sabouraud's dextrose, and yeast-nitrogen broth media (1 ml/tube). The minimal inhibitory and minimal fungicidal concentrations of 5-fluorocytosine and fluconazole for all species were > 100 micrograms/ml. All Fusarium isolates, except F. equiseti (3.125 micrograms), gave minimal inhibitory concentrations of 12.5-100 micrograms/ml for hamycin. The values for amphotericin B, itraconazole, ketoconazole, JAI-amphotericin B, and amphotericin B combined with 5-fluorocytosine were 1.56-100, 0.78-50, 3.125-100,50-100, and 1.56 to > 100 micrograms/ml, respectively. Although a wide range of minimal inhibitory concentrations was recorded for most of the isolates studied, it appears that some--F. solani, F. oxysporum, F. chlamydosporum, F. equiseti, and F. moliniforme--were more susceptible to amphotericin B, itraconazole, ketoconazole, hamycin, and amphotericin B in the presence of 5-fluorocytosine. All isolates showed resistance to 5-fluorocytosine and fluconazole. The minimal fungicidal concentrations were either the same or several times higher than the minimal inhibitory concentrations.

  3. Defining "Sector 3" Poultry Layer Farms in Relation to H5N1-HPAI-An Example from Java, Indonesia.

    PubMed

    Durr, Peter A; Wibowo, Michael Haryadi; Tarigan, Simson; Artanto, Sidna; Rosyid, Murni Nurhasanah; Ignjatovic, Jagoda

    2016-05-01

    To help guide surveillance and control of highly pathogenic avian influenza subtype H5N1 (H5N1-HPAI), the Food and Agriculture Organization of the United Nations in 2004 devised a poultry farm classification system based on a combination of production and biosecurity practices. Four "Sectors" were defined, and this scheme has been widely adopted within Indonesia to guide national surveillance and control strategies. Nevertheless, little detailed research into the robustness of this classification system has been conducted, particularly as it relates to independent, small to medium-sized commercial poultry farms (Sector 3). Through an analysis of questionnaire data collected as part of a survey of layer farms in western and central Java, all of which were classified as Sector 3 by local veterinarians, we provide benchmark data on what defines this sector. A multivariate analysis of the dataset, using hierarchical cluster analysis, identified three groupings of the farms, which were defined by a combination of production-and biosecurity-related variables, particularly those related to farm size and (the lack of) washing and disinfection practices. Nevertheless, the relationship between production-related variables and positive biosecurity practices was poor, and larger farms did not have an overall higher total biosecurity score than small or medium-sized ones. Further research is required to define the properties of poultry farms in Indonesia that are most closely related to effective biosecurity and the prevention of H5N1-HPAI.

  4. CWA Section 404 Mitigation

    EPA Pesticide Factsheets

    The Council on Environmental Quality has defined mitigation in its implementing regulations for the National Environmental Policy Act to include avoiding, minimizing, rectifying, reducing over time, and compensating for impacts.

  5. Uropathogenic Escherichia coli Metabolite-Dependent Quiescence and Persistence May Explain Antibiotic Tolerance during Urinary Tract Infection

    PubMed Central

    Leatham-Jensen, Mary P.; Mokszycki, Matthew E.; Rowley, David C.; Deering, Robert; Camberg, Jodi L.; Sokurenko, Evgeni V.; Tchesnokova, Veronika L.; Frimodt-Møller, Jakob; Leth Nielsen, Karen; Sun, Gongqin

    2016-01-01

    ABSTRACT In the present study, it is shown that although Escherichia coli CFT073, a human uropathogenic (UPEC) strain, grows in liquid glucose M9 minimal medium, it fails to grow on glucose M9 minimal medium agar plates seeded with ≤106 CFU. The cells on glucose plates appear to be in a “quiescent” state that can be prevented by various combinations of lysine, methionine, and tyrosine. Moreover, the quiescent state is characteristic of ~80% of E. coli phylogenetic group B2 multilocus sequence type 73 strains, as well as 22.5% of randomly selected UPEC strains isolated from community-acquired urinary tract infections in Denmark. In addition, E. coli CFT073 quiescence is not limited to glucose but occurs on agar plates containing a number of other sugars and acetate as sole carbon sources. It is also shown that a number of E. coli CFT073 mini-Tn5 metabolic mutants (gnd, gdhA, pykF, sdhA, and zwf) are nonquiescent on glucose M9 minimal agar plates and that quiescence requires a complete oxidative tricarboxylic acid (TCA) cycle. In addition, evidence is presented that, although E. coli CFT073 quiescence and persistence in the presence of ampicillin are alike in that both require a complete oxidative TCA cycle and each can be prevented by amino acids, E. coli CFT073 quiescence occurs in the presence or absence of a functional rpoS gene, whereas maximal persistence requires a nonfunctional rpoS. Our results suggest that interventions targeting specific central metabolic pathways may mitigate UPEC infections by interfering with quiescence and persistence. IMPORTANCE Recurrent urinary tract infections (UTIs) affect 10 to 40% of women. In up to 77% of those cases, the recurrent infections are caused by the same uropathogenic E. coli (UPEC) strain that caused the initial infection. Upon infection of urothelial transitional cells in the bladder, UPEC appear to enter a nongrowing quiescent intracellular state that is thought to serve as a reservoir responsible for recurrent UTIs. Here, we report that many UPEC strains enter a quiescent state when ≤106 CFU are seeded on glucose M9 minimal medium agar plates and show that mutations in several genes involved in central carbon metabolism prevent quiescence, as well as persistence, possibly identifying metabolic pathways involved in UPEC quiescence and persistence in vivo. PMID:27303698

  6. Turbine blade cooling

    DOEpatents

    Staub, F.W.; Willett, F.T.

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

  7. Systems and methods for separating particles utilizing engineered acoustic contrast capture particles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaduchak, Gregory; Ward, Michael D.

    An apparatus for separating particles from a medium includes a capillary defining a flow path therein that is in fluid communication with a medium source. The medium source includes engineered acoustic contrast capture particle having a predetermined acoustic contrast. The apparatus includes a vibration generator that is operable to produce at least one acoustic field within the flow path. The acoustic field produces a force potential minima for positive acoustic contrast particles and a force potential minima for negative acoustic contrast particles in the flow path and drives the engineered acoustic contrast capture particles to either the force potential minimamore » for positive acoustic contrast particles or the force potential minima for negative acoustic contrast particles.« less

  8. Apparatus for separating particles utilizing engineered acoustic contrast capture particles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kaduchak, Gregory; Ward, Michael D

    An apparatus for separating particles from a medium includes a capillary defining a flow path therein that is in fluid communication with a medium source. The medium source includes engineered acoustic contrast capture particle having a predetermined acoustic contrast. The apparatus includes a vibration generator that is operable to produce at least one acoustic field within the flow path. The acoustic field produces a force potential minima for positive acoustic contrast particles and a force potential minima for negative acoustic contrast particles in the flow path and drives the engineered acoustic contrast capture particles to either the force potential minimamore » for positive acoustic contrast particles or the force potential minima for negative acoustic contrast particles.« less

  9. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    1999-07-20

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  10. Turbine blade cooling

    DOEpatents

    Staub, Fred Wolf; Willett, Fred Thomas

    2000-01-01

    A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

  11. Electromagnetic backscattering from a random distribution of lossy dielectric scatterers

    NASA Technical Reports Server (NTRS)

    Lang, R. H.

    1980-01-01

    Electromagnetic backscattering from a sparse distribution of discrete lossy dielectric scatterers occupying a region 5 was studied. The scatterers are assumed to have random position and orientation. Scattered fields are calculated by first finding the mean field and then by using it to define an equivalent medium within the volume 5. The scatterers are then viewed as being embedded in the equivalent medium; the distorted Born approximation is then used to find the scattered fields. This technique represents an improvement over the standard Born approximation since it takes into account the attenuation of the incident and scattered waves in the equivalent medium. The method is used to model a leaf canopy when the leaves are modeled by lossy dielectric discs.

  12. Robotic surgery update.

    PubMed

    Jacobsen, G; Elli, F; Horgan, S

    2004-08-01

    Minimally invasive surgical techniques have revolutionized the field of surgery. Telesurgical manipulators (robots) and new information technologies strive to improve upon currently available minimally invasive techniques and create new possibilities. A retrospective review of all robotic cases at a single academic medical center from August 2000 until November 2002 was conducted. A comprehensive literature evaluation on robotic surgical technology was also performed. Robotic technology is safely and effectively being applied at our institution. Robotic and information technologies have improved upon minimally invasive surgical techniques and created new opportunities not attainable in open surgery. Robotic technology offers many benefits over traditional minimal access techniques and has been proven safe and effective. Further research is needed to better define the optimal application of this technology. Credentialing and educational requirements also need to be delineated.

  13. Examining the recent climate through the lens of ecology: inferences from temporal pattern analysis.

    Treesearch

    Paul F. Hessburg; Ellen E. Kuhlmann; Thomas W. Swetnam

    2005-01-01

    Ecological theory asserts that the climate of a region exerts top-down controls on regional ecosystem patterns and processes, across space and time. To provide empirical evidence of climatic controls, it would be helpful to define climatic regions that minimized variance in key climate attributes, within climatic regions-define the periods and features of climatic...

  14. Minimization of Defective Products in The Department of Press Bridge & Rib Through Six Sigma DMAIC Phases

    NASA Astrophysics Data System (ADS)

    Rochman, YA; Agustin, A.

    2017-06-01

    This study proposes the DMAIC Six Sigma approach of Define, Measure, Analyze, Improve/Implement and Control (DMAIC) to minimizing the number of defective products in the bridge & rib department. There are 5 types of defects were the most dominant are broken rib, broken sound board, strained rib, rib sliding and sound board minori. The imperative objective is to improve the quality through the DMAIC phases. In the define phase, the critical to quality (CTQ) parameters was identified minimization of product defects through the pareto chart and FMEA. In this phase, to identify waste based on the current value stream mapping. In the measure phase, the specified control limits product used to maintain the variations of the product, the calculation of the value of DPMO (Defect Per Million Opportunities) and the calculation of the value of sigma level. In analyze phase, determine the type of defect of the most dominant and identify the causes of defective products. In the improve phase, the existing design was modified through various alternative solutions by conducting brainstorming sessions. In this phase, the solution was identified based on the results of FMEA. Improvements were made to the seven priority causes of disability based on the highest RPN value. In the control phase, focusing on improvements to be made. Proposed improvements include making and define standard operating procedures, improving the quality and eliminate waste defective products.

  15. Saccharomyces Cerevisiae Cho2 Mutants Are Deficient in Phospholipid Methylation and Cross-Pathway Regulation of Inositol Synthesis

    PubMed Central

    Summers, E. F.; Letts, V. A.; McGraw, P.; Henry, S. A.

    1988-01-01

    Five allelic Saccharomyces cerevisiae mutants deficient in the methylation of phosphatidylethanolamine (PE) have been isolated, using two different screening techniques. Biochemical analysis suggested that these mutants define a locus, designated CHO2, that may encode a methyltransferase. Membranes of cho2 mutant cells grown in defined medium contain approximately 10% phosphatidylcholine (PC) and 40-50% PE as compared to wild-type levels of 40-45% PC and 15-20% PE. In spite of this greatly altered phospholipid composition, cho2 mutant cells are viable in defined medium and are not auxotrophic for choline or other phospholipid precursors such as monomethylethanolamine (MME). However, analysis of yeast strains carrying more than one mutation affecting phospholipid biosynthesis indicated that some level of methylated phospholipid is essential for viability. The cho2 locus was shown by tetrad analysis to be unlinked to other loci affecting phospholipid synthesis. Interestingly, cho2 mutants and other mutant strains that produce reduced levels of methylated phospholipids are unable to properly repress synthesis of the cytoplasmic enzyme inositol-1-phosphate synthase. This enzyme was previously shown to be regulated at the level of mRNA abundance in response to inositol and choline in the growth medium. We cloned the CHO2 gene on a 3.6-kb genomic DNA fragment and created a null allele of cho2 by disrupting the CHO2 gene in vivo. The cho2 disruptant, like all other cho2 mutants, is viable, exhibits altered regulation of inositol biosynthesis and is not auxotrophic for choline or MME. PMID:3066687

  16. Improved chemically defined basal medium (CMRL-1969) for primary monkey kidney and human diploid cells.

    PubMed

    Healy, G M; Teleki, S; von Seefried, A; Walton, M J; Macmorine, H G

    1971-01-01

    An improved tissue culture basal medium, CMRL-1969, supplemented with serum, has been evaluated by measuring the growth responses of primary cultures of trypsin-dispersed monkey kidney cells (PMKC) and of an established culture of a human diploid cell strain (HDCS). Medium H597, an early modification of medium 199 which has been used successfully in the preparation of poliomyelitis vaccine for 15 years, was used for comparison. In addition, parallel testing was done with Basal Medium Eagle (BME) widely used for the growth of HDCS. The improvements in basal medium CMRL-1969 are attributed to changes in amino acid concentrations, in vitamin composition, and, in particular, to enhanced buffering capacity. The latter has been achieved by the use of free-base amino acids and by increasing the dibasic sodium phosphate. The new medium has already been used to advantage for the production of polioviruses in PMKC where equivalent titers were obtained from cultures initiated with 70% of the number of cells required with earlier media. The population-doubling time was reduced in this system. Also, with small inocula of HDCS, the time required to obtain maximum cell yield was shorter with CMRL-1969 than with BME. Both media were supplemented with 10% calf serum. Maximum cell yields after repeated subcultivation in the new basal medium were greatly increased and the stability of the strain, as shown by chromosomal analysis, was not affected. Basal medium CMRL-1969 can be prepared easily in liquid or powdered form.

  17. Thermal interpretation of infrared dynamics in de Sitter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rigopoulos, Gerasimos, E-mail: gerasimos.rigopoulos@ncl.ac.uk

    The infrared dynamics of a light, minimally coupled scalar field in de Sitter spacetime with Ricci curvature R = 12 H {sup 2}, averaged over horizon sized regions of physical volume V {sub H} = (4π/3)(1/ H ){sup 3}, can be interpreted as Brownian motion in a medium with de Sitter temperature T {sub DS} = h-bar H /2π. We demonstrate this by directly deriving the effective action of scalar field fluctuations with wavelengths larger than the de Sitter curvature radius and generalizing Starobinsky's seminal results on stochastic inflation. The effective action describes stochastic dynamics and the fluctuating force drivesmore » the field to an equilibrium characterized by a thermal Gibbs distribution at temperature T {sub DS} which corresponds to a de Sitter invariant state. Hence, approach towards this state can be interpreted as thermalization. We show that the stochastic kinetic energy of the coarse-grained description corresponds to the norm of ∂{sub μ}φ and takes a well defined value per horizon volume ½((∇φ){sup 2}) = − ½ T {sub DS}/ V {sub H} . This approach allows for the non-perturbative computation of the de Sitter invariant stress energy tensor ( T {sub μν}) for an arbitrary scalar potential.« less

  18. Description of International Caenorhabditis elegans Experiment first flight (ICE-FIRST)

    PubMed Central

    Szewczyk, N.J.; Tillman, J.; Conley, C.A.; Granger, L.; Segalat, L.; Higashitani, A.; Honda, S.; Honda, Y.; Kagawa, H.; Adachi, R.; Higashibata, A.; Fujimoto, N.; Kuriyama, K.; Ishioka, N.; Fukui, K.; Baillie, D.; Rose, A.; Gasset, G.; Eche, B.; Chaput, D.; Viso, M.

    2008-01-01

    Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads. PMID:22146801

  19. Description of International Caenorhabditis elegans Experiment first flight (ICE-FIRST)

    NASA Astrophysics Data System (ADS)

    Szewczyk, N. J.; Tillman, J.; Conley, C. A.; Granger, L.; Segalat, L.; Higashitani, A.; Honda, S.; Honda, Y.; Kagawa, H.; Adachi, R.; Higashibata, A.; Fujimoto, N.; Kuriyama, K.; Ishioka, N.; Fukui, K.; Baillie, D.; Rose, A.; Gasset, G.; Eche, B.; Chaput, D.; Viso, M.

    2008-09-01

    Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads.

  20. Description of International Caenorhabditis elegans Experiment first flight (ICE-FIRST).

    PubMed

    Szewczyk, N J; Tillman, J; Conley, C A; Granger, L; Segalat, L; Higashitani, A; Honda, S; Honda, Y; Kagawa, H; Adachi, R; Higashibata, A; Fujimoto, N; Kuriyama, K; Ishioka, N; Fukui, K; Baillie, D; Rose, A; Gasset, G; Eche, B; Chaput, D; Viso, M

    2008-09-15

    Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads.

  1. Growth Media Affect Assessment of Antimicrobial Activity of Plant-Derived Polyphenols.

    PubMed

    Xu, Xin; Ou, Zhen M; Wu, Christine D

    2018-01-01

    This study aimed to investigate the effects of different microbial growth media on the laboratory assessment of antimicrobial activity of natural polyphenolic compounds. The inhibition of the tea polyphenol EGCG on growth of selected oral microorganisms was evaluated in complex media and a protein-free chemically defined medium (CDM). Other antimicrobial agents (polyphenolic grape seed extract, plant alkaloid berberine, methyl salicylate, and chlorhexidine gluconate) were also tested in the study. The presence of proteins and their effects on the antimicrobial activity of EGCG were investigated by the addition of BSA to the CDM. The MICs of EGCG against test oral microorganisms were 4 to 64 times higher in complex media than in CDM. The polyphenolic grape seed extract exhibited similar discrepancies. However, the MICs of the nonpolyphenolic compounds (berberine, methyl salicylate, and chlorhexidine) were not significantly different between the two growth media. The MIC of EGCG against S. mutans UA159 in CDM with added BSA was 16 times higher than that in CDM alone. Therefore, nonproteinaceous CDM should be used to avoid interference of proteins with the active ingredients when testing the antimicrobial activity of plant-derived polyphenolic compounds against microorganisms. This will also minimize the discrepancies noted in results obtained by different investigators.

  2. Insertional Mutations in the Hydrogenase vhc and frc Operons Encoding Selenium-Free Hydrogenases in Methanococcus voltae

    PubMed Central

    Berghofer, Y.; Klein, A.

    1995-01-01

    Methanococcus voltae, which contains four different gene groups that encode [NiFe]-hydrogenases, was transformed with integration vectors to achieve polar inactivation of two of the four hydrogenase operons that encode the selenium-free enzymes Vhc and Frc. Transformants which were selected by their acquired puromycin resistance showed site-specific insertions in either the vhc or frc operon by single crossover events. Southern hybridization revealed tandem integrations of whole vectors in the vhc operon, whereas only one vector copy was found in the frc operon. Northern (RNA) hybridizations showed a pac transcript of defined size, indicating strong termination in front of the hydrogenase genes downstream. In spite of the apparent abolition of expression of selenium-free hydrogenases through these polar insertions, they were not lethal to cells upon growth in selenium-deprived minimal medium, which we had previously shown to strongly induce transcription of the respective operons in M. voltae. Instead, like wild-type control cultures, transformants responded to selenium deprivation only with a reduction in growth rate. We conclude that loss of the potential to express a selenium-free hydrogenase can nevertheless be balanced by very small amounts of selenium hydrogenases under laboratory conditions in which the hydrogen supply is not likely to be a limiting growth factor. PMID:16535019

  3. Multiphase contrast medium injection for optimization of computed tomographic coronary angiography.

    PubMed

    Budoff, Matthew Jay; Shinbane, Jerold S; Child, Janis; Carson, Sivi; Chau, Alex; Liu, Stephen H; Mao, SongShou

    2006-02-01

    Electron beam angiography is a minimally invasive imaging technique. Adequate vascular opacification throughout the study remains a critical issue for image quality. We hypothesized that vascular image opacification and uniformity of vascular enhancement between slices can be improved using multiphase contrast medium injection protocols. We enrolled 244 consecutive patients who were randomized to three different injection protocols: single-phase contrast medium injection (Group 1), dual-phase contrast medium injection with each phase at a different injection rate (Group 2), and a three-phase injection with two phases of contrast medium injection followed by a saline injection phase (Group 3). Parameters measured were aortic opacification based on Hounsfield units and uniformity of aortic enhancement at predetermined slices (locations from top [level 1] to base [level 60]). In Group 1, contrast opacification differed across seven predetermined locations (scan levels: 1st versus 60th, P < .05), demonstrating significant nonuniformity. In Group 2, there was more uniform vascular enhancement, with no significant differences between the first 50 slices (P > .05). In Group 3, there was greater uniformity of vascular enhancement and higher mean Hounsfield units value across all 60 images, from the aortic root to the base of the heart (P < .05). The three-phase injection protocol improved vascular opacification at the base of the heart, as well as uniformity of arterial enhancement throughout the study.

  4. On optimal current patterns for electrical impedance tomography.

    PubMed

    Demidenko, Eugene; Hartov, Alex; Soni, Nirmal; Paulsen, Keith D

    2005-02-01

    We develop a statistical criterion for optimal patterns in planar circular electrical impedance tomography. These patterns minimize the total variance of the estimation for the resistance or conductance matrix. It is shown that trigonometric patterns (Isaacson, 1986), originally derived from the concept of distinguishability, are a special case of our optimal statistical patterns. New optimal random patterns are introduced. Recovering the electrical properties of the measured body is greatly simplified when optimal patterns are used. The Neumann-to-Dirichlet map and the optimal patterns are derived for a homogeneous medium with an arbitrary distribution of the electrodes on the periphery. As a special case, optimal patterns are developed for a practical EIT system with a finite number of electrodes. For a general nonhomogeneous medium, with no a priori restriction, the optimal patterns for the resistance and conductance matrix are the same. However, for a homogeneous medium, the best current pattern is the worst voltage pattern and vice versa. We study the effect of the number and the width of the electrodes on the estimate of resistivity and conductivity in a homogeneous medium. We confirm experimentally that the optimal patterns produce minimum conductivity variance in a homogeneous medium. Our statistical model is able to discriminate between a homogenous agar phantom and one with a 2 mm air hole with error probability (p-value) 1/1000.

  5. Physiological and Genetic Analyses Leading to Identification of a Biochemical Role for the moeA (Molybdate Metabolism) Gene Product in Escherichia coli†

    PubMed Central

    Hasona, Adnan; Ray, Ramesh M.; Shanmugam, K. T.

    1998-01-01

    A unique class of chlorate-resistant mutants of Escherichia coli which produced formate hydrogenlyase and nitrate reductase activities only when grown in medium with limiting amounts of sulfur compounds was isolated. These mutants failed to produce the two molybdoenzyme activities when cultured in rich medium or glucose-minimal medium. The mutations in these mutants were localized in the moeA gene. Mutant strains with polar mutations in moeA which are also moeB did not produce active molybdoenzymes in any of the media tested. moeA mutants with a second mutation in either cysDNCJI or cysH gene lost the ability to produce active molybdoenzyme even when grown in medium limiting in sulfur compounds. The CysDNCJIH proteins along with CysG catalyze the conversion of sulfate to sulfide. Addition of sulfide to the growth medium of moeA cys double mutants suppressed the MoeA− phenotype. These results suggest that in the absence of MoeA protein, the sulfide produced by the sulfate activation/reduction pathway combines with molybdate in the production of activated molybdenum. Since hydrogen sulfide is known to interact with molybdate in the production of thiomolybdate, it is possible that the MoeA-catalyzed activated molybdenum is a form of thiomolybdenum species which is used in the synthesis of molybdenum cofactor from Mo-free molybdopterin. PMID:9515915

  6. [First definition of minimal care model: the role of nurses, physiotherapists, dietitians and psychologists in preventive and rehabilitative cardiology].

    PubMed

    Bettinardi, Ornella; da Vico, Letizia; Pierobon, Antonia; Iannucci, Manuela; Maffezzoni, Barbara; Borghi, Silvana; Ferrari, Marina; Brazzo, Silvia; Mazza, Antonio; Sommaruga, Marinella; Angelino, Elisabetta; Biffi, Barbara; Agostini, Susanna; Masini, Maria Luisa; Ambrosetti, Marco; Faggiano, Pompilio; Griffo, Raffaele

    2014-09-01

    Rehabilitative and preventive cardiology (CRP) is configured as intervention prevention to "gain health" through a process of multifactorial care that reduces disability and the risk of subsequent cardiovascular events. It makes use of an interdisciplinary team in which every professional needs to have multiple intervention paths because of the different levels of clinical and functional complexity of cardiac patients who currently have access to the rehabilitation. The document refers to the use of interventions by nurses, physiotherapists, dietitians and psychologists that are part of the rehabilitation team of CRP. Interventions of which have been documented, on scientific bases and clinical practice, empirical effectiveness and organizational efficiency. The methodological approach of this paper is a first attempt to define, through the model of consensus, the minimum standards for a CRP evidence based characterized by clearly defined criteria that can be used by operators of CRP. The document describes the activities to be carried out in each of the phases included in the pathways of care by nurses, physiotherapists, dietitians and psychologists. The routes identified were divided, according to the type of patients who have access to the CRP and to the phases of care, including the initial assessment, intervention, evaluation and final reporting, in high medium and low complexity. Examples of models of reporting, used by the operators of the team according to the principles of good clinical practice, are provided. This is made to allow traceability of operations, encourage communication inside the working group and within the patient and the caregiver. Also to give any possible indication for the post-rehabilitation.

  7. Storage of RF photons in minimal conditions

    NASA Astrophysics Data System (ADS)

    Cromières, J.-P.; Chanelière, T.

    2018-02-01

    We investigate the minimal conditions to store coherently a RF pulse in a material medium. We choose a commercial quartz as a memory support because it is a widely available component with a high Q-factor. Pulse storage is obtained by varying dynamically the light-matter coupling with an analog switch. This parametric driving of the quartz dynamics can be alternatively interpreted as a stopped-light experiment. We obtain an efficiency of 26%, a storage time of 209 μs and a time-to-bandwidth product of 98 by optimizing the pulse temporal shape. The coherent character of the storage is demonstrated. Our goal is to connect different types of memories in the RF and optical domain for quantum information processing. Our motivation is essentially fundamental.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Woohyun; Katipamula, Srinivas; Lutes, Robert G.

    This report describes how the intelligent load control (ILC) algorithm can be implemented to achieve peak demand reduction while minimizing impacts on occupant comfort. The algorithm was designed to minimize the additional sensors and minimum configuration requirements to enable a scalable and cost-effective implementation for both large and small-/medium-sized commercial buildings. The ILC algorithm uses an analytic hierarchy process (AHP) to dynamically prioritize the available curtailable loads based on both quantitative (deviation of zone conditions from set point) and qualitative rules (types of zone). Although the ILC algorithm described in this report was highly tailored to work with rooftop units,more » it can be generalized for application to other building loads such as variable-air-volume (VAV) boxes and lighting systems.« less

  9. Lyophilic matrix method for dissolution and release studies of nanoscale particles.

    PubMed

    Pessi, Jenni; Svanbäck, Sami; Lassila, Ilkka; Hæggström, Edward; Yliruusi, Jouko

    2017-10-25

    We introduce a system with a lyophilic matrix to aid dissolution studies of powders and particulate systems. This lyophilic matrix method (LM method) is based on the ability to discriminate between non-dissolved particles and the dissolved species. In the LM method the test substance is embedded in a thin lyophilic core-shell matrix. This permits rapid contact with the dissolution medium while minimizing dispersion of non-dissolved particles without presenting a substantial diffusion barrier. The method produces realistic dissolution and release results for particulate systems, especially those featuring nanoscale particles. By minimizing method-induced effects on the dissolution profile of nanopowders, the LM method overcomes shortcomings associated with current dissolution tests. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Evolution of the INMARSAT aeronautical system: Service, system, and business considerations

    NASA Technical Reports Server (NTRS)

    Sengupta, Jay R.

    1995-01-01

    A market-driven approach was adopted to develop enhancements to the Inmarsat-Aeronautical system, to address the requirements of potential new market segments. An evolutionary approach and well differentiated product/service portfolio was required, to minimize system upgrade costs and market penetration, respectively. The evolved system definition serves to minimize equipment cost/size/mass for short/medium range aircraft, by reducing the antenna gain requirement and relaxing the performance requirements for non safety-related communications. A validation program involving simulation, laboratory tests, over-satellite tests and flight trials is being conducted to confirm the system definition. Extensive market research has been conducted to determine user requirements and to quantify market demand for future Inmarsat Aero-1 AES, using sophisticated computer assisted survey techniques.

  11. Gonococcal salpingitis in gynaecology--myth or missed?

    PubMed Central

    Sparks, R A; Davies, A J

    1976-01-01

    A series of 25 cases of gonococcal salpingitis were seen in a teaching hospital between October, 1972, and March, 1975. These cases formed 29 per cent of all cases of salpingitis excluding post-abortal cases. The majority were investigated at the bedside by taking films and cultures from the cervix and urethra. The films were stained by Gram's method and specimens for culture were streaked on to prewarmed Gonococcal Selective Medium (Oxoid) and the plates were incubated at once in a CO2-enriched atmosphere at 37 degrees C. A group of cases was identified with minimal symptoms and minimal, or absent, signs; in such cases the diagnosis may be unsuspected. Reasons are advanced for the failure of other gynaecological units to recognize gonococcal salpingitis. PMID:819091

  12. Cultivation of Plasmodium falciparum parasites in a serum-free medium.

    PubMed

    Ofulla, A V; Okoye, V C; Khan, B; Githure, J I; Roberts, C R; Johnson, A J; Martin, S K

    1993-09-01

    The elimination of serum from Plasmodium falciparum culture media could decrease costs, enhance procurement, and improve the feasibility of large-scale production of parasite material. We provide a semi-defined, serum-free formulation, of commercially available constituents that supports P. falciparum parasite growth at rates comparable with those obtained with serum-supplemented media. The medium is composed of RPMI 1640 to which HEPES, extra glucose, bicarbonate, and hypoxanthine have been added. Bovine albumin and serum-derived, lipids-cholesterol-rich mixture are then used in place of serum.

  13. Out of the Blue and Into the Black: Creation of the United States Space Force.

    DTIC Science & Technology

    1998-03-01

    organizational diagnosis as a theorem for strategic change. An autopsy of related research and literature was conducted in order to establish justification for a separate service to advance space power for the nation. The first dimension examined is the medium of space. Defining the medium, along with such areas as airpower and space power establishes a factual foundation from which to launch the idea of a separate service. Reasoning for and against a separate service is presented, including application of the Organizational Diagnosis to the Air

  14. Robotic intelligence kernel

    DOEpatents

    Bruemmer, David J [Idaho Falls, ID

    2009-11-17

    A robot platform includes perceptors, locomotors, and a system controller. The system controller executes a robot intelligence kernel (RIK) that includes a multi-level architecture and a dynamic autonomy structure. The multi-level architecture includes a robot behavior level for defining robot behaviors, that incorporate robot attributes and a cognitive level for defining conduct modules that blend an adaptive interaction between predefined decision functions and the robot behaviors. The dynamic autonomy structure is configured for modifying a transaction capacity between an operator intervention and a robot initiative and may include multiple levels with at least a teleoperation mode configured to maximize the operator intervention and minimize the robot initiative and an autonomous mode configured to minimize the operator intervention and maximize the robot initiative. Within the RIK at least the cognitive level includes the dynamic autonomy structure.

  15. Exploration of Configuration Options for a Large Civil Compound Helicopter

    NASA Technical Reports Server (NTRS)

    Russell, Carl; Johnson, Wayne

    2013-01-01

    Multiple compound helicopter configurations are designed using a combination of rotorcraft sizing and comprehensive analysis codes. Results from both the conceptual design phase and rotor comprehensive analysis are presented. The designs are evaluated for their suitability to a short-to-medium-haul civil transport mission carrying a payload of 90 passengers. Multiple metrics are used to determine the best configuration, with heavy emphasis placed on minimizing fuel burn.

  16. Expression and purification of ELP-intein-tagged target proteins in high cell density E. coli fermentation.

    PubMed

    Fong, Baley A; Wood, David W

    2010-10-19

    Elastin-like polypeptides (ELPs) are useful tools that can be used to non-chromatographically purify proteins. When paired with self-cleaving inteins, they can be used as economical self-cleaving purification tags. However, ELPs and ELP-tagged target proteins have been traditionally expressed using highly enriched media in shake flask cultures, which are generally not amenable to scale-up. In this work, we describe the high cell-density expression of self-cleaving ELP-tagged targets in a supplemented minimal medium at a 2.5 liter fermentation scale, with increased yields and purity compared to traditional shake flask cultures. This demonstration of ELP expression in supplemented minimal media is juxtaposed to previous expression of ELP tags in extract-based rich media. We also describe several sets of fed-batch conditions and their impact on ELP expression and growth medium cost. By using fed batch E. coli fermentation at high cell density, ELP-intein-tagged proteins can be expressed and purified at high yield with low cost. Further, the impact of media components and fermentation design can significantly impact the overall process cost, particularly at large scale. This work thus demonstrates an important advances in the scale up of self-cleaving ELP tag-mediated processes.

  17. Expression and purification of ELP-intein-tagged target proteins in high cell density E. coli fermentation

    PubMed Central

    2010-01-01

    Background Elastin-like polypeptides (ELPs) are useful tools that can be used to non-chromatographically purify proteins. When paired with self-cleaving inteins, they can be used as economical self-cleaving purification tags. However, ELPs and ELP-tagged target proteins have been traditionally expressed using highly enriched media in shake flask cultures, which are generally not amenable to scale-up. Results In this work, we describe the high cell-density expression of self-cleaving ELP-tagged targets in a supplemented minimal medium at a 2.5 liter fermentation scale, with increased yields and purity compared to traditional shake flask cultures. This demonstration of ELP expression in supplemented minimal media is juxtaposed to previous expression of ELP tags in extract-based rich media. We also describe several sets of fed-batch conditions and their impact on ELP expression and growth medium cost. Conclusions By using fed batch E. coli fermentation at high cell density, ELP-intein-tagged proteins can be expressed and purified at high yield with low cost. Further, the impact of media components and fermentation design can significantly impact the overall process cost, particularly at large scale. This work thus demonstrates an important advances in the scale up of self-cleaving ELP tag-mediated processes. PMID:20959011

  18. Production of L-glutamic Acid with Corynebacterium glutamicum (NCIM 2168) and Pseudomonas reptilivora (NCIM 2598): A Study on Immobilization and Reusability

    PubMed Central

    Shyamkumar, Rajaram; Moorthy, Innasi Muthu Ganesh; Ponmurugan, Karuppiah; Baskar, Rajoo

    2014-01-01

    Background L-glutamic acid is one of the major amino acids that is present in a wide variety of foods. It is mainly used as a food additive and flavor enhancer in the form of sodium salt. Corynebacterium glutamicum (C. glutamicum) is one of the major organisms widely used for glutamic acid production. Methods The study was dealing with immobilization of C. glutamicum and mixed culture of C. glutamicum and Pseudomonas reptilivora (P. reptilivora) for L-glutamic acid production using submerged fermentation. 2, 3 and 5% sodium alginate concentrations were used for production and reusability of immobilized cells for 5 more trials. Results The results revealed that 2% sodium alginate concentration produced the highest yield (13.026±0.247 g/l by C. glutamicum and 16.026±0.475 g/l by mixed immobilized culture). Moreover, reusability of immobilized cells was evaluated in 2% concentration with 5 more trials. However, when the number of cycles increased, the production of L-glutamic acid decreased. Conclusion Production of glutamic acid using optimized medium minimizes the time needed for designing the medium composition. It also minimizes external contamination. Glutamic acid production gradually decreased due to multiple uses of beads and consequently it reduces the shelf life. PMID:25215180

  19. Production of L-glutamic Acid with Corynebacterium glutamicum (NCIM 2168) and Pseudomonas reptilivora (NCIM 2598): A Study on Immobilization and Reusability.

    PubMed

    Shyamkumar, Rajaram; Moorthy, Innasi Muthu Ganesh; Ponmurugan, Karuppiah; Baskar, Rajoo

    2014-07-01

    L-glutamic acid is one of the major amino acids that is present in a wide variety of foods. It is mainly used as a food additive and flavor enhancer in the form of sodium salt. Corynebacterium glutamicum (C. glutamicum) is one of the major organisms widely used for glutamic acid production. The study was dealing with immobilization of C. glutamicum and mixed culture of C. glutamicum and Pseudomonas reptilivora (P. reptilivora) for L-glutamic acid production using submerged fermentation. 2, 3 and 5% sodium alginate concentrations were used for production and reusability of immobilized cells for 5 more trials. The results revealed that 2% sodium alginate concentration produced the highest yield (13.026±0.247 g/l by C. glutamicum and 16.026±0.475 g/l by mixed immobilized culture). Moreover, reusability of immobilized cells was evaluated in 2% concentration with 5 more trials. However, when the number of cycles increased, the production of L-glutamic acid decreased. Production of glutamic acid using optimized medium minimizes the time needed for designing the medium composition. It also minimizes external contamination. Glutamic acid production gradually decreased due to multiple uses of beads and consequently it reduces the shelf life.

  20. Cultivation of mammalian cells using a single-use pneumatic bioreactor system.

    PubMed

    Obom, Kristina M; Cummings, Patrick J; Ciafardoni, Janelle A; Hashimura, Yasunori; Giroux, Daniel

    2014-10-10

    Recent advances in mammalian, insect, and stem cell cultivation and scale-up have created tremendous opportunities for new therapeutics and personalized medicine innovations. However, translating these advances into therapeutic applications will require in vitro systems that allow for robust, flexible, and cost effective bioreactor systems. There are several bioreactor systems currently utilized in research and commercial settings; however, many of these systems are not optimal for establishing, expanding, and monitoring the growth of different cell types. The culture parameters most challenging to control in these systems include, minimizing hydrodynamic shear, preventing nutrient gradient formation, establishing uniform culture medium aeration, preventing microbial contamination, and monitoring and adjusting culture conditions in real-time. Using a pneumatic single-use bioreactor system, we demonstrate the assembly and operation of this novel bioreactor for mammalian cells grown on micro-carriers. This bioreactor system eliminates many of the challenges associated with currently available systems by minimizing hydrodynamic shear and nutrient gradient formation, and allowing for uniform culture medium aeration. Moreover, the bioreactor's software allows for remote real-time monitoring and adjusting of the bioreactor run parameters. This bioreactor system also has tremendous potential for scale-up of adherent and suspension mammalian cells for production of a variety therapeutic proteins, monoclonal antibodies, stem cells, biosimilars, and vaccines.

  1. EFFECT OF TEMPERATURE ON THE COMPOSITION OF FATTY ACIDS IN ESCHERICHIA COLI

    PubMed Central

    Marr, Allen G.; Ingraham, John L.

    1962-01-01

    Marr, Allen G. (University of California, Davis) and John L. Ingraham. Effect of temperature on composition of fatty acids in Escherichia coli. J. Bacteriol. 84:1260–1267. 1962.—Variations in the temperature of growth and in the composition of the medium alter the proportions of individual fatty acids in the lipids of Escherichia coli. As the temperature of growth is lowered, the proportion of unsaturated fatty acids (hexadecenoic and octadecenoic acids) increases. The increase in content of unsaturated acids with a decrease in temperature of growth occurs in both minimal and complex media. Cells harvested in the stationary phase contained large amounts of cyclopropane fatty acids (methylenehexadecanoic and methylene octadecanoic acids) in comparison with cells harvested during exponential growth. Cells grown in a chemostat, limited by the concentration of ammonium salts, show a much higher content of saturated fatty acids (principally palmitic acid) than do cells harvested from an exponentially-growing batch culture in the same medium. Cells grown in a chemostat, limited by the concentration of glucose, show a slightly higher content of unsaturated fatty acids than cells from the corresponding batch culture. The results do not indicate a direct relation between fatty acid composition and minimal growth temperature. PMID:16561982

  2. Fish Viruses: Buffers and Methods for Plaquing Eight Agents Under Normal Atmosphere

    PubMed Central

    Wolf, Ken; Quimby, M. C.

    1973-01-01

    A universal procedure was sought for plaque assay of eight fish viruses (bluegill myxovirus, channel catfish virus, eel virus, Egtved virus, infectious hematopoietic necrosis virus, infectious pancreatic necrosis virus, lymphocystis virus, and the agent of spring viremia of carp (Rhabdovirus carpio), in dish cultures of various fish cells. Eagle minimal essential medium with sodium bicarbonate-CO2 buffer (Earle’s salt solution) was compared with minimal essential medium buffered principally with tris (hydroxymethyl)aminomethane or N-2-hydroxyethylpiperazine-N′-2′-ethanesulfonic acid at a pH or in the range of 7.6 to 8.0 depending upon temperature. Five fish cell lines collectively capable of replicating all fish viruses thus far isolated were tested and quantitatively found to grow comparably well in the three media. Two-phase (gel-liquid) media incorporating the various buffer systems allowed plaquing at 15 to 33 C either in partial pressures of CO2 or in normal atmosphere, but greater efficiency and sensitivity were obtained with the organic buffers, and, overall, the best results were obtained with tris(hydroxymethyl)aminomethane. Epizootiological data, specific fish cell line response, and plaque morphology permit presumptive identification of most of the agents. At proper pH, use of organic buffers obviates the need for CO2 incubators. Images PMID:4349252

  3. 40 CFR Table 1a to Subpart Ec of... - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Waste Incinerators for Which Construction is Commenced After June 20, 1996 Pt. 60, Subpt. Ec, Table 1A... Facilities as Defined in § 60.50c(a)(1) and (2) Pollutant Units (7 percent oxygen, dry basis) Emissions... matter Milligrams per dry standard cubic meter (grains per dry standard cubic foot) 69 (0.03) 34 (0.015...

  4. 40 CFR Table 1b to Subpart Ec of... - Emissions Limits for Small, Medium, and Large HMIWI at Affected Facilities as Defined in § 60.50c...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Waste Incinerators for Which Construction is Commenced After June 20, 1996 Pt. 60, Subpt. Ec, Table 1B... Facilities as Defined in § 60.50c(a)(3) and (4) Pollutant Units (7 percent oxygen, dry basis) Emissions... matter Milligrams per dry standard cubic meter (grains per dry standard cubic foot) 66 (0.029) 22 (0.0095...

  5. Recycling of drinking water treatment residue as an additional medium in columns for effective P removal from eutrophic surface water.

    PubMed

    Wang, Changhui; Wu, Yu; Bai, Leilei; Zhao, Yaqian; Yan, Zaisheng; Jiang, Helong; Liu, Xin

    2018-07-01

    This study assesses the feasibility of recycling drinking water treatment residue (DWTR) to treat eutrophic surface water in a one-year continuous flow column test. Heat-treated DWTR was used as an additional medium (2%-4%) in columns in case excessive organic matter and N were released from the DWTR to surface water. The results indicated that with minimal undesirable effects on other water properties, DWTR addition substantially enhanced P removal, rendering P concentrations in treated water oligotrophic and treated water unsuitable for Microcystis aeruginosa breeding. Long-term stable P removal by DWTR-column treatment was mainly attributed to the relatively low P levels in raw water (<0.108 mg L -1 ) and high P adsorption capability of DWTR, as confirmed by increases in amorphous Al/Fe in DWTR after the tests and low adsorption of P in the mobile forms. The major components of DWTR showed minimal changes, and potential metal pollution from DWTR was not a factor to consider during recycling. DWTR also enriched functional bacterial genera that benefitted biogeochemical cycles and multiple pollution control (e.g., Dechloromonas, Geobacter, Leucobacter, Nitrospira, Rhodoplanes, and Sulfuritalea); an apparent decrease in Mycobacterium with potential pathogenicity was observed in DWTR-columns. Regardless, limited denitrification of DWTR-columns was observed as a result of low bioavailability of C in surface water. This finding indicates that DWTR can be used with other methods to ensure denitrification for enhanced treatment effects. Overall, the use of DWTR as an additional medium in column systems can potentially treat eutrophic surface water. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. High substrate uptake rates empower Vibrio natriegens as production host for industrial biotechnology.

    PubMed

    Hoffart, Eugenia; Grenz, Sebastian; Lange, Julian; Nitschel, Robert; Müller, Felix; Schwentner, Andreas; Feith, André; Lenfers-Lücker, Mira; Takors, Ralf; Blombach, Bastian

    2017-09-08

    The productivity of industrial fermentation processes is essentially limited by the biomass specific substrate consumption rate (q S ) of the applied microbial production system. Since q S depends on the growth rate (μ), we highlight the potential of the fastest growing non-pathogenic bacterium, Vibrio natriegens , as novel candidate for future biotechnological processes. V. natriegens grows rapidly in BHIN complex medium with a μ of up to 4.43 h -1 (doubling time of 9.4 min) as well as in minimal medium supplemented with various industrially relevant substrates. Bioreactor cultivations in minimal medium with glucose showed that V. natriegens possesses an exceptionally high q S under aerobic (3.90 ± 0.08 g g -1 h -1 ) and anaerobic (7.81 ± 0.71 g g -1 h -1 ) conditions. Fermentations with resting cells of genetically engineered V. natriegens under anaerobic conditions yielded an overall volumetric productivity of 0.56 ± 0.10 g alanine L -1 min -1 (i.e. 34 g L -1 h -1 ). These inherent properties render V. natriegens a promising new microbial platform for future industrial fermentation processes operating with high productivity. Importance Low conversion rates are one major challenge to realize microbial fermentation processes for the production of commodities operating competitively to existing petrochemical approaches. For this reason, we screened for a novel platform organism possessing superior characteristics to traditionally employed microbial systems. We identified the fast growing Vibrio natriegens which exhibits a versatile metabolism and shows striking growth and conversion rates, as a solid candidate to reach outstanding productivities. Due to these inherent characteristics V. natriegens can speed up common laboratory routines, is suitable for already existing production procedures, and forms an excellent foundation to engineer next generation bioprocesses. Copyright © 2017 American Society for Microbiology.

  7. The effect of titanium dioxide (TiO2) nano-objects, and their aggregates and agglomerates greater than 100nm (NOAA) on microbes under UV irradiation.

    PubMed

    Yamada, Ikuho; Nomura, Kazuki; Iwahashi, Hitoshi; Horie, Masanori

    2016-01-01

    Today, nanoparticles are used in many products. One of the most common nanoparticles is titanium dioxide (TiO2). These particles generate reactive oxygen species (ROS) upon UV irradiation. Although nanoparticles are very useful in many products, there are concerns about their biological and ecological effects when released into the environment. Thus, it was assessed that the effect of TiO2 nano-objects, and their aggregates and agglomerates greater than 100nm (NOAA) on microbes under UV irradiation by using Escherichia coli and Saccharomyces cerevisiae. ROS generation was evaluated by adding TiO2 nanoparticles and methylene blue to distilled water. We also assessed growth inhibition by adding TiO2 nanoparticles and microbes in minimal agar medium. Moreover, microbial inactivation was assessed by adding TiO2 nanoparticles and microbes to PBS. Upon UV irradiation, TiO2-NOAAs decomposed methylene blue and generated ROS. TiO2-NOAAs also decomposed methylene blue in minimal agar medium under UV irradiation; however, they did not inhibit microbial growth. Surprisingly, TiO2-NOAAs in the medium protect microbes from UV irradiation as colony formation was observed only near TiO2-NOAAs. In PBS, TiO2-NOAAs did not inactivate microbes but instead protected microbes from lethal UV irradiation. These results suggest that the amount of ROS generated by TiO2-NOAAs is not enough to inactivate microbes. In fact, our results suggest that TiO2-NOAAs may protect microbes from UV irradiations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. The use of minimal spanning trees in particle physics

    DOE PAGES

    Rainbolt, J. Lovelace; Schmitt, M.

    2017-02-14

    Minimal spanning trees (MSTs) have been used in cosmology and astronomy to distinguish distributions of points in a multi-dimensional space. They are essentially unknown in particle physics, however. We briefly define MSTs and illustrate their properties through a series of examples. We show how they might be applied to study a typical event sample from a collider experiment and conclude that MSTs may prove useful in distinguishing different classes of events.

  9. The use of minimal spanning trees in particle physics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rainbolt, J. Lovelace; Schmitt, M.

    Minimal spanning trees (MSTs) have been used in cosmology and astronomy to distinguish distributions of points in a multi-dimensional space. They are essentially unknown in particle physics, however. We briefly define MSTs and illustrate their properties through a series of examples. We show how they might be applied to study a typical event sample from a collider experiment and conclude that MSTs may prove useful in distinguishing different classes of events.

  10. Technology Assessment for Future MILSATCOM Systems; An Update of the EHF Bands

    DTIC Science & Technology

    1980-10-01

    converging these efforts, the MSO has prepared a "Technology Development Program Plan" ( TDPP ). The TOPP defines a coordinated approach to the R&D...required to insure the availability of the technology necessary to support future systems. Some of the objectives of the TDPP are: to minimize...and TDPP have illuminated the need for technology development efforts directed toward minimizing the cost- risk and schedule-risk, and insuring the

  11. 47 CFR 95.831 - Service requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... that it provides substantial service within the service area. Substantial service is defined as a service that is sound, favorable, and substantially above a level of service which might minimally warrant...

  12. Short- and long-term effects of conscious, minimally conscious and unconscious brand logos.

    PubMed

    Muscarella, Charlotte; Brintazzoli, Gigliola; Gordts, Sarah; Soetens, Eric; Van den Bussche, Eva

    2013-01-01

    Unconsciously presented information can influence our behavior in an experimental context. However, whether these effects can be translated to a daily life context, such as advertising, is strongly debated. What hampers this translation is the widely accepted notion of the short-livedness of unconscious representations. The effect of unconscious information on behavior is assumed to rapidly vanish within a few hundreds of milliseconds. Using highly familiar brand logos (e.g., the logo of McDonald's) as subliminal and supraliminal primes in two priming experiments, we assessed whether these logos were able to elicit behavioral effects after a short (e.g., 350 ms), a medium (e.g., 1000 ms), and a long (e.g., 5000 ms) interval. Our results demonstrate that when real-life information is presented minimally consciously or even unconsciously, it can influence our subsequent behavior, even when more than five seconds pass between the presentation of the minimally conscious or unconscious information and the behavior on which it exerts its influence.

  13. Goal-directed ultrasound in the detection of long-bone fractures

    NASA Technical Reports Server (NTRS)

    Marshburn, Thomas H.; Legome, Eric; Sargsyan, Ashot; Li, Shannon Melton James; Noble, Vicki A.; Dulchavsky, Scott A.; Sims, Carrie; Robinson, David

    2004-01-01

    BACKGROUND: New portable ultrasound (US) systems are capable of detecting fractures in the remote setting. However, the accuracy of ultrasound by physicians with minimal ultrasound training is unknown. METHODS: After one hour of standardized training, physicians with minimal US experience clinically evaluated patients presenting with pain and trauma to the upper arm or leg. The investigators then performed a long-bone US evaluation, recording their impression of fracture presence or absence. Results of the examination were compared with routine plain or computer aided radiography (CT). RESULTS: 58 patients were examined. The sensitivity and specificity of US were 92.9% and 83.3%, and of the physical examination were 78.6% and 90.0%, respectively. US provided improved sensitivity with less specificity compared with physical examination in the detection of fractures in long bones. CONCLUSION: Ultrasound scans by minimally trained clinicians may be used to rule out a long-bone fracture in patients with a medium to low probability of fracture.

  14. Short- and Long-Term Effects of Conscious, Minimally Conscious and Unconscious Brand Logos

    PubMed Central

    Gordts, Sarah; Soetens, Eric; Van den Bussche, Eva

    2013-01-01

    Unconsciously presented information can influence our behavior in an experimental context. However, whether these effects can be translated to a daily life context, such as advertising, is strongly debated. What hampers this translation is the widely accepted notion of the short-livedness of unconscious representations. The effect of unconscious information on behavior is assumed to rapidly vanish within a few hundreds of milliseconds. Using highly familiar brand logos (e.g., the logo of McDonald's) as subliminal and supraliminal primes in two priming experiments, we assessed whether these logos were able to elicit behavioral effects after a short (e.g., 350 ms), a medium (e.g., 1000 ms), and a long (e.g., 5000 ms) interval. Our results demonstrate that when real-life information is presented minimally consciously or even unconsciously, it can influence our subsequent behavior, even when more than five seconds pass between the presentation of the minimally conscious or unconscious information and the behavior on which it exerts its influence. PMID:23658681

  15. Building Research Cyberinfrastructure at Small/Medium Research Institutions

    ERIC Educational Resources Information Center

    Agee, Anne; Rowe, Theresa; Woo, Melissa; Woods, David

    2010-01-01

    A 2006 ECAR study defined cyberinfrastructure as the coordinated aggregate of "hardware, software, communications, services, facilities, and personnel that enable researchers to conduct advanced computational, collaborative, and data-intensive research." While cyberinfrastructure was initially seen as support for scientific and…

  16. Internal shocks in microquasar jets with a continuous Lorentz factor modulation

    NASA Astrophysics Data System (ADS)

    Pjanka, Patryk; Stone, James M.

    2018-06-01

    We perform relativistic hydrodynamic simulations of internal shocks formed in microquasar jets by continuous variation of the bulk Lorentz factor, in order to investigate the internal shock model. We consider one-, two-, and flicker noise 20-mode variability. We observe emergence of a forward-reverse shock structure for each peak of the Lorentz factor modulation. The high pressure in the shocked layer launches powerful outflows perpendicular to the jet beam into the ambient medium. These outflows dominate the details of the jet's kinetic energy thermalization. They are responsible for mixing between the jet and the surrounding medium and generate powerful shocks in the latter. These results do not concur with the popular picture of well-defined internal shells depositing energy as they collide within the confines of the jet, in fact collisions between internal shells themselves are quite rare in our continuous formulation of the problem. For each of our simulations, we calculate the internal energy deposited in the system, the `efficiency' of this deposition (defined as the ratio of internal to total flow energy), and the maximum temperature reached in order to make connections to emission mechanisms. We probe the dependence of these diagnostics on the Lorentz factor variation amplitudes, modulation frequencies, as well as the initial density ratio between the jet and the ambient medium.

  17. Lyapunov Exponents of Minimizing Measures for Globally Positive Diffeomorphisms in All Dimensions

    NASA Astrophysics Data System (ADS)

    Arnaud, M.-C.

    2016-05-01

    The globally positive diffeomorphisms of the 2 n-dimensional annulus are important because they represent what happens close to a completely elliptic periodic point of a symplectic diffeomorphism where the torsion is positive definite. For these globally positive diffeomorphisms, an Aubry-Mather theory was developed by Garibaldi and Thieullen that provides the existence of some minimizing measures. Using the two Green bundles {G_-} and {G_+} that can be defined along the support of these minimizing measures, we will prove that there is a deep link between: the angle between {G_-} and {G_+} along the support of the considered measure {μ};

  18. Profitability and sustainability of small - medium scale palm biodiesel plant

    NASA Astrophysics Data System (ADS)

    Solikhah, Maharani Dewi; Kismanto, Agus; Raksodewanto, Agus; Peryoga, Yoga

    2017-06-01

    The mandatory of biodiesel application at 20% blending (B20) has been started since January 2016. It creates huge market for biodiesel industry. To build large-scale biodiesel plant (> 100,000 tons/year) is most favorable for biodiesel producers since it can give lower production cost. This cost becomes a challenge for small - medium scale biodiesel plants. However, current biodiesel plants in Indonesia are located mainly in Java and Sumatra, which then distribute biodiesel around Indonesia so that there is an additional cost for transportation from area to area. This factor becomes an opportunity for the small - medium scale biodiesel plants to compete with the large one. This paper discusses the profitability of small - medium scale biodiesel plants conducted on a capacity of 50 tons/day using CPO and its derivatives. The study was conducted by performing economic analysis between scenarios of biodiesel plant that using raw material of stearin, PFAD, and multi feedstock. Comparison on the feasibility of scenarios was also conducted on the effect of transportation cost and selling price. The economic assessment shows that profitability is highly affected by raw material price so that it is important to secure the source of raw materials and consider a multi-feedstock type for small - medium scale biodiesel plants to become a sustainable plant. It was concluded that the small - medium scale biodiesel plants will be profitable and sustainable if they are connected to palm oil mill, have a captive market, and are located minimally 200 km from other biodiesel plants. The use of multi feedstock could increase IRR from 18.68 % to 56.52 %.

  19. Control of Clostridium perfringens-induced necrotic enteritis in broilers by target-released butyric acid, fatty acids and essential oils.

    PubMed

    Timbermont, L; Lanckriet, A; Dewulf, J; Nollet, N; Schwarzer, K; Haesebrouck, F; Ducatelle, R; Van Immerseel, F

    2010-04-01

    The efficacy of target-released butyric acid, medium-chain fatty acids (C(6) to C(12) but mainly lauric acid) and essential oils (thymol, cinnamaldehyde, essential oil of eucalyptus) micro-encapsulated in a poly-sugar matrix to control necrotic enteritis was investigated. The minimal inhibitory concentrations of the different additives were determined in vitro, showing that lauric acid, thymol, and cinnamaldehyde are very effective in inhibiting the growth of Clostridium perfringens. The in vivo effects were studied in two trials in an experimental necrotic enteritis model in broiler chickens. In the first trial, four groups of chickens were fed a diet supplemented with butyric acid, with essential oils, with butyric acid in combination with medium-chain fatty acids, or with butyric acid in combination with medium-chain fatty acids and essential oils. In all groups except for the group receiving only butyric acid, a significant decrease in the number of birds with necrotic lesions was found compared with the infected, untreated control group. In the second trial the same products were tested but at a higher concentration. An additional group was fed a diet supplemented with only medium-chain fatty acids. In all groups except for that receiving butyric acid in combination with medium-chain fatty acids and essential oils, a significant decrease in the number of birds with necrotic lesions was found compared with the infected, untreated control group. These results suggest that butyric acid, medium-chain fatty acids and/or essential oils may contribute to the prevention of necrotic enteritis in broilers.

  20. An efficient algorithm for automatic phase correction of NMR spectra based on entropy minimization

    NASA Astrophysics Data System (ADS)

    Chen, Li; Weng, Zhiqiang; Goh, LaiYoong; Garland, Marc

    2002-09-01

    A new algorithm for automatic phase correction of NMR spectra based on entropy minimization is proposed. The optimal zero-order and first-order phase corrections for a NMR spectrum are determined by minimizing entropy. The objective function is constructed using a Shannon-type information entropy measure. Entropy is defined as the normalized derivative of the NMR spectral data. The algorithm has been successfully applied to experimental 1H NMR spectra. The results of automatic phase correction are found to be comparable to, or perhaps better than, manual phase correction. The advantages of this automatic phase correction algorithm include its simple mathematical basis and the straightforward, reproducible, and efficient optimization procedure. The algorithm is implemented in the Matlab program ACME—Automated phase Correction based on Minimization of Entropy.

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