Sample records for acid rtca cycle

  1. Computational exploration of the chemical structure space of possible reverse tricarboxylic acid cycle constituents.

    PubMed

    Meringer, Markus; Cleaves, H James

    2017-12-13

    The reverse tricarboxylic acid (rTCA) cycle has been explored from various standpoints as an idealized primordial metabolic cycle. Its simplicity and apparent ubiquity in diverse organisms across the tree of life have been used to argue for its antiquity and its optimality. In 2000 it was proposed that chemoinformatics approaches support some of these views. Specifically, defined queries of the Beilstein database showed that the molecules of the rTCA are heavily represented in such compound databases. We explore here the chemical structure "space," e.g. the set of organic compounds which possesses some minimal set of defining characteristics, of the rTCA cycle's intermediates using an exhaustive structure generation method. The rTCA's chemical space as defined by the original criteria and explored by our method is some six to seven times larger than originally considered. Acknowledging that each assumption in what is a defining criterion making the rTCA cycle special limits possible generative outcomes, there are many unrealized compounds which fulfill these criteria. That these compounds are unrealized could be due to evolutionary frozen accidents or optimization, though this optimization may also be for systems-level reasons, e.g., the way the pathway and its elements interface with other aspects of metabolism.

  2. Origin of the Reductive Tricarboxylic Acid (rTCA) Cycle-Type CO2 Fixation: A Perspective

    PubMed Central

    Fujishima, Kosuke

    2017-01-01

    The reductive tricarboxylic acid (rTCA) cycle is among the most plausible candidates for the first autotrophic metabolism in the earliest life. Extant enzymes fixing CO2 in this cycle contain cofactors at the catalytic centers, but it is unlikely that the protein/cofactor system emerged at once in a prebiotic process. Here, we discuss the feasibility of non-enzymatic cofactor-assisted drive of the rTCA reactions in the primitive Earth environments, particularly focusing on the acetyl-CoA conversion to pyruvate. Based on the energetic and mechanistic aspects of this reaction, we propose that the deep-sea hydrothermal vent environments with active electricity generation in the presence of various sulfide catalysts are a promising setting for it to progress. Our view supports the theory of an autotrophic origin of life from primordial carbon assimilation within a sulfide-rich hydrothermal vent.

  3. Oxaloacetate-to-malate conversion by mineral photoelectrochemistry: implications for the viability of the reductive tricarboxylic acid cycle in prebiotic chemistry

    NASA Astrophysics Data System (ADS)

    Guzman, Marcelo I.; Martin, Scot T.

    2008-10-01

    The carboxylic acids produced by the reductive tricarboxylic acid (rTCA) cycle are possibly a biosynthetic core of initial life, although several steps such as the reductive kinetics of oxaloacetate (OAA) to malate (MA) are problematic by conventional chemical routes. In this context, we studied the kinetics of this reaction as promoted by ZnS mineral photoelectrochemistry. The quantum efficiency φMA of MA production from the photoelectrochemical reduction of OAA followed φMA=0.13 [OAA] (2.1×10-3+[OAA])-1 and was independent of temperature (5 to 50°C). To evaluate the importance of this forward rate under a prebiotic scenario, we also studied the temperature-dependent rate of the backward thermal decarboxylation of OAA to pyruvate (PA), which followed an Arrhenius behavior as log (k-2)=11.74 4956/T, where k-2 is in units of s-1. These measured rates were employed in conjunction with the indirectly estimated carboxylation rate of PA to OAA to assess the possible importance of mineral photoelectrochemistry in the conversion of OAA to MA under several scenarios of prebiotic conditions on early Earth. As an example, our analysis shows that there is 90% efficiency with a forward velocity of 3 yr/cycle for the OAA→MA step of the rTCA cycle at 280 K. Efficiency and velocity both decrease for increasing temperature. These results suggest high viability for mineral photoelectrochemistry as an enzyme-free engine to drive the rTCA cycle through the early aeons of early Earth, at least for the investigated OAA→MA step.

  4. Metabolic flux analysis of the mixotrophic metabolisms in the green sulfur bacterium Chlorobaculum tepidum.

    PubMed

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

    2010-12-10

    The photosynthetic green sulfur bacterium Chlorobaculum tepidum assimilates CO(2) and organic carbon sources (acetate or pyruvate) during mixotrophic growth conditions through a unique carbon and energy metabolism. Using a (13)C-labeling approach, this study examined biosynthetic pathways and flux distributions in the central metabolism of C. tepidum. The isotopomer patterns of proteinogenic amino acids revealed an alternate pathway for isoleucine synthesis (via citramalate synthase, CimA, CT0612). A (13)C-assisted flux analysis indicated that carbons in biomass were mostly derived from CO(2) fixation via three key routes: the reductive tricarboxylic acid (RTCA) cycle, the pyruvate synthesis pathway via pyruvate:ferredoxin oxidoreductase, and the CO(2)-anaplerotic pathway via phosphoenolpyruvate carboxylase. During mixotrophic growth with acetate or pyruvate as carbon sources, acetyl-CoA was mainly produced from acetate (via acetyl-CoA synthetase) or citrate (via ATP citrate lyase). Pyruvate:ferredoxin oxidoreductase converted acetyl-CoA and CO(2) to pyruvate, and this growth-rate control reaction is driven by reduced ferredoxin generated during phototrophic growth. Most reactions in the RTCA cycle were reversible. The relative fluxes through the RTCA cycle were 80∼100 units for mixotrophic cultures grown on acetate and 200∼230 units for cultures grown on pyruvate. Under the same light conditions, the flux results suggested a trade-off between energy-demanding CO(2) fixation and biomass growth rate; C. tepidum fixed more CO(2) and had a higher biomass yield (Y(X/S), mole carbon in biomass/mole substrate) in pyruvate culture (Y(X/S) = 9.2) than in acetate culture (Y(X/S) = 6.4), but the biomass growth rate was slower in pyruvate culture than in acetate culture.

  5. Diversity of Total Bacterial Communities and Chemoautotrophic Populations in Sulfur-Rich Sediments of Shallow-Water Hydrothermal Vents off Kueishan Island, Taiwan.

    PubMed

    Wang, Li; Cheung, Man Kit; Liu, Rulong; Wong, Chong Kim; Kwan, Hoi Shan; Hwang, Jiang-Shiou

    2017-04-01

    Shallow-water hydrothermal vents (HTVs) are an ecologically important habitat with a geographic origin similar to that of deep-sea HTVs. Studies on shallow-water HTVs have not only facilitated understanding of the influences of vents on local ecosystems but also helped to extend the knowledge on deep-sea vents. In this study, the diversity of bacterial communities in the sediments of shallow-water HTVs off Kueishan Island, Taiwan, was investigated by examining the 16S ribosomal RNA gene as well as key functional genes involved in chemoautotrophic carbon fixation (aclB, cbbL and cbbM). In the vent area, Sulfurovum and Sulfurimonas of Epsilonproteobacteria appeared to dominate the benthic bacterial community. Results of aclB gene analysis also suggested involvement of these bacteria in carbon fixation using the reductive tricarboxylic acid (rTCA) cycle. Analysis of the cbbM gene showed that Alphaproteobacterial members such as the purple non-sulfur bacteria were the major chemoautotrophic bacteria involving in carbon fixation via the Calvin-Benson-Bassham (CBB) cycle. However, they only accounted for <2% of the total bacterial community in the vent area. These findings suggest that the rTCA cycle is the major chemoautotrophic carbon fixation pathway in sediments of the shallow-water HTVs off Kueishan Island.

  6. Chemolithoautotrophy and its Relation to Magnetism and Biomineralization in Marine Magnetotactic Bacteria

    NASA Astrophysics Data System (ADS)

    Bazylinski, D. A.; Williams, T. J.; Zhang, C. L.; Scott, J. H.

    2005-12-01

    All cultured, marine, magnetite-producing, magnetotactic bacteria (MB) are capable of chemolithoautotrophy and use a number of electron donors to support this mode of growth including reduced sulfur compounds. Several vibrioid strains are known to rely on the Calvin-Benson-Bassham (CBB) cycle for autotrophy. An obligately microaerophilic, magnetite-producing, coccoid strain (MC-1) grew with sulfide and thiosulfate as electron donors and 14C-labelling experiments showed that virtually all cell C was derived from H14CO3-/14CO2 confirming autotrophy in this strain. Cell-free extracts of strain MC-1 did not exhibit ribulose-1,5-bisphosphate carboxylase-oxygenase (RubisCO) activity and nor were RubisCO genes found in the draft genome of the organism. Cell extracts also did not exhibit carbon monoxide dehydrogenase activity indicating that the acetyl-CoA pathway also does not function in strain MC-1. The 13C content of whole cells of strain MC-1 relative to the 13C content of the H14CO3-/14CO2 used for growth (Δδ13C) was -11.4 ppt. Cellular fatty acids showed enrichment of 13C relative to biomass. Activities for three key enzymes of the reverse or reductive tricarboxylic acid (rTCA) cycle were demonstrated for MC-1: fumarate reductase, pyruvate: acceptor oxidoreductase and 2-oxoglutarate: acceptor oxidoreductase. Although ATP citrate lyase (another key enzyme of the rTCA cycle) activity was not detected in cell-free extracts of strain MC-1 using commonly used assays for this enzyme, cell-free extract was found to rapidly cleave citrate, and the reaction was dependent upon the presence of ATP, coenzyme A and NADH. Thus, we infer the presence of an ATP-dependent citrate-cleaving enzyme or enzymes. The Δδ13C value and results from enzyme studies are consistent with the operation of the rTCA cycle for autotrophy in strain MC-1. Strain MC-1 appears to be the first known member of the alpha-Proteobacteria to assimilate CO2 during autotrophic growth using the rTCA cycle. Based on the type of chemolithoautotrophy described above, it is clear why marine magnetite-producing MB occupy a precise location, the oxic-anoxic interface, in vertical chemical gradients within chemically-stratified coastal environments: they must have an electron donor, sulfide and perhaps others, and an electron acceptor, O2. The presumed function of magnetosomes is that the magnetic dipole resulting from the magnetosomes aids the cell in locating and maintaining an optimal position within vertical chemical gradients. MB process large amounts of Fe in the biomineralization of magnetosomes: cells consist of 1-3% Fe (dry wt). Because of this, and the fact that many chemolithoautotrophic, non-magnetotactic bacteria occupy a similar niche, we have been investigating possible physiological reasons for the production of magnetosomes and the processing of such large amounts of Fe. We have found that some marine vibrioid strains grow in O2-gradient medium with Fe(II) as the electron donor. Cells appear to oxidize the Fe(II) and produce a layer of Fe oxyhydroxides within the gradient suggesting that cells obtain energy from the oxidation of Fe(II).

  7. 78 FR 72747 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-03

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management...: Notice of RTCA Program Management Committee Meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Program Management Committee. DATES: The meeting will be held December...

  8. 76 FR 74842 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-01

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee... RTCA Program Management Committee meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Program Management Committee DATES: The meeting will be held December 13, 2011...

  9. 77 FR 12905 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-02

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management...: Notice of RTCA Program Management Committee Meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of the RTCA Program Management Committee. DATES: The meeting will be held...

  10. 78 FR 43962 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-22

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management...: Notice of RTCA Program Management Committee Meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Program Management Committee. DATES: The meeting will be held August...

  11. 78 FR 57673 - RTCA Program Management Committee; Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee...: Notice of RTCA Program Management Committee meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Program Management Committee. DATES: The meeting will be held October...

  12. 75 FR 61552 - RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC) SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Government/Industry Air Traffic Management... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Government/Industry Air Traffic...

  13. 75 FR 39091 - RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-07

    ... RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Government/Industry Air Traffic Management... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Government/Industry Air Traffic...

  14. 78 FR 14151 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-04

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management...: Notice of RTCA Program Management Committee Meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Program Management Committee. DATES: The meeting will be held March 20...

  15. 77 FR 31421 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management...: Notice of RTCA Program Management Committee Meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of the RTCA Program Management Committee. DATES: The meeting will be held June...

  16. 78 FR 51810 - Twenty-Fourth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ...., 1150 18th Street NW., Suite 910, Washington, DC 20036. FOR FURTHER INFORMATION CONTACT: The RTCA... (202) 833-9434, or Web site at http://www.rtca.org . SUPPLEMENTARY INFORMATION: Pursuant to section 10... Security System Standard for Airport Access Control, RTCA Paper No. 168-13/SC224-048 TOR Review--Status of...

  17. Rewiring the reductive tricarboxylic acid pathway and L-malate transport pathway of Aspergillus oryzae for overproduction of L-malate.

    PubMed

    Liu, Jingjing; Xie, Zhipeng; Shin, Hyun-Dong; Li, Jianghua; Du, Guocheng; Chen, Jian; Liu, Long

    2017-07-10

    Aspergillus oryzae finds wide application in the food, feed, and wine industries, and is an excellent cell factory platform for production of organic acids. In this work, we achieved the overproduction of L-malate by rewiring the reductive tricarboxylic acid (rTCA) pathway and L-malate transport pathway of A. oryzae NRRL 3488. First, overexpression of native pyruvate carboxylase and malate dehydrogenase in the rTCA pathway improved the L-malate titer from 26.1gL -1 to 42.3gL -1 in shake flask culture. Then, the oxaloacetate anaplerotic reaction was constructed by heterologous expression of phosphoenolpyruvate carboxykinase and phosphoenolpyruvate carboxylase from Escherichia coli, increasing the L-malate titer to 58.5gL -1 . Next, the export of L-malate from the cytoplasm to the external medium was strengthened by overexpression of a C4-dicarboxylate transporter gene from A. oryzae and an L-malate permease gene from Schizosaccharomyces pombe, improving the L-malate titer from 58.5gL -1 to 89.5gL -1 . Lastly, guided by transcription analysis of the expression profile of key genes related to L-malate synthesis, the 6-phosphofructokinase encoded by the pfk gene was identified as a potential limiting step for L-malate synthesis. Overexpression of pfk with the strong sodM promoter increased the L-malate titer to 93.2gL -1 . The final engineered A. oryzae strain produced 165gL -1 L-malate with a productivity of 1.38gL -1 h -1 in 3-L fed-batch culture. Overall, we constructed an efficient L-malate producer by rewiring the rTCA pathway and L-malate transport pathway of A. oryzae NRRL 3488, and the engineering strategy adopted here may be useful for the construction of A. oryzae cell factories to produce other organic acids. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. 76 FR 72240 - Twenty-Seventh Meeting: RTCA Special Committee 206: Aeronautical Information and Meteorological...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Twenty-Seventh Meeting: RTCA Special... Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 206..., 2011 FRAC OSED [[Page 72241

  19. 75 FR 26321 - Seventeenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... RTCA Workspace Web Tool Special Committee Status Overview Workgroup Updates WG1--Systems Engineering..., Washington, DC 20036; telephone (202) 833-9339; fax (202) 833-9434; Web site http://www.rtca.org...

  20. Spatial Differences in East Scotia Ridge Hydrothermal Vent Food Webs: Influences of Chemistry, Microbiology and Predation on Trophodynamics

    PubMed Central

    Reid, William D. K.; Sweeting, Christopher J.; Wigham, Ben D.; Zwirglmaier, Katrin; Hawkes, Jeffrey A.; McGill, Rona A. R.; Linse, Katrin; Polunin, Nicholas V. C.

    2013-01-01

    The hydrothermal vents on the East Scotia Ridge are the first to be explored in the Antarctic and are dominated by large peltospiroid gastropods, stalked barnacles (Vulcanolepas sp.) and anomuran crabs (Kiwa sp.) but their food webs are unknown. Vent fluid and macroconsumer samples were collected at three vent sites (E2, E9N and E9S) at distances of tens of metres to hundreds of kilometres apart with contrasting vent fluid chemistries to describe trophic interactions and identify potential carbon fixation pathways using stable isotopes. δ13C of dissolved inorganic carbon from vent fluids ranged from −4.6‰ to 0.8‰ at E2 and from −4.4‰ to 1.5‰ at E9. The lowest macroconsumer δ13C was observed in peltospiroid gastropods (−30.0‰ to −31.1‰) and indicated carbon fixation via the Calvin-Benson-Bassham (CBB) cycle by endosymbiotic gamma-Proteobacteria. Highest δ13C occurred in Kiwa sp. (−19.0‰ to −10.5‰), similar to that of the epibionts sampled from their ventral setae. Kiwa sp. δ13C differed among sites, which were attributed to spatial differences in the epibiont community and the relative contribution of carbon fixed via the reductive tricarboxylic acid (rTCA) and CBB cycles assimilated by Kiwa sp. Site differences in carbon fixation pathways were traced into higher trophic levels e.g. a stichasterid asteroid that predates on Kiwa sp. Sponges and anemones at the periphery of E2 assimilated a proportion of epipelagic photosynthetic primary production but this was not observed at E9N. Differences in the δ13C and δ34S values of vent macroconsumers between E2 and E9 sites suggest the relative contributions of photosynthetic and chemoautotrophic carbon fixation (rTCA v CBB) entering the hydrothermal vent food webs vary between the sites. PMID:23762393

  1. 75 FR 80885 - Fifteenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ..., Boeing Commercial Airplane Group. FOR FURTHER INFORMATION CONTACT: RTCA Secretariat, 1828 L Street, NW..., 2010 (RTCA Paper No. 250-10/SC216-031). Report on the PMC/ICC action on SC 216 TOR. Publication...

  2. 75 FR 14482 - Fifty-First Meeting: RTCA Special Committee 186: Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ..., WG-1, Wake Vortex, ARINC Room. RTCA--All Day, WG-4, Application Technical Requirements, Colson Board... Vortex, MacIntosh-NBAA Room & Hilton-ATA Room. RTCA--All Day, WG-4, Application Technical Requirements...

  3. 75 FR 28852 - Ninth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-24

    ... approach and landing. FOR FURTHER INFORMATION CONTACT: (1) RTCA Secretariat, 1828 L Street, NW., Suite 805, Washington, DC 20036; telephone (202) 833-9339; fax (202) 833-9434; Web site http://www.rtca.org...

  4. 76 FR 58077 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held September 28, 2011 from 8:30 a.m. to 1:30 p.m...

  5. 75 FR 52590 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held September 15, 2010 from 8:30 a.m. to 1:30 p.m...

  6. 76 FR 27743 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held May 26, 2011 from 12 p.m. to 1 p.m. ADDRESSES: The...

  7. 75 FR 56654 - RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA NextGen Advisory Committee (NAC) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA NextGen Advisory Committee (NAC) SUMMARY: The FAA published a Notice in the Federal Register on September 3, 2010 (75-FR-54221...

  8. 75 FR 1116 - RTCA Government/Industry Air Traffic Management Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-08

    ... Government/Industry Air Traffic Management Advisory Committee. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Government/Industry Air Traffic Management Advisory Committee... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Government/Industry Air Traffic...

  9. 76 FR 34124 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held June 22, 2011 from 8:30 a.m. to 1:30 p.m. ADDRESSES...

  10. 75 FR 71182 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held December 8, 2010 from 8:30 a.m. to 1:30 p.m. ADDRESSES...

  11. 76 FR 11847 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held March 17, 2011 from 8:30 a.m. to 1:30 p.m. ADDRESSES...

  12. 75 FR 9017 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held March 17, 2010 from 8:30 a.m. to 1:30 p.m. ADDRESSES...

  13. 75 FR 29811 - RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Program Management Committee... Management Committee. DATES: The meeting will be held June 10, 2010 from 8:30 a.m. to 1:30 p.m. ADDRESSES...

  14. 76 FR 54526 - 26th Meeting: RTCA Special Committee 206: Aeronautical Information and Meteorological Data Link

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... 206: Aeronautical Information and Meteorological Data Link AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 206: Aeronautical Information and Meteorological... of RTCA Special Committee 206: Aeronautical Information and Meteorological Data Link Services. DATES...

  15. 75 FR 60495 - Eighteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-30

    ..., 20036; telephone (202) 833-9339; fax (202) 833-9434; Web site http://www.rtca.org . SUPPLEMENTARY... Product Team Breakout Session. RTCA Workspace Web Tool. Closing Plenary Session. Plenary Adjourns until... Engineering Workgroup. Control and Communications Workgroup. Sense and Avoid Workgroup. Wednesday, October...

  16. 77 FR 25524 - Sixth Meeting: RTCA, NextGen Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ... provide the following information: Name (as it appears on your identification), Company, Phone number, Country of origin. FOR FURTHER INFORMATION CONTACT: The RTCA Secretariat, 1150 18th Street NW., Suite 910....rtca.org . SUPPLEMENTARY INFORMATION: Pursuant to section 10(a)(2) of the Federal Advisory Committee...

  17. 76 FR 24957 - Nineteenth Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ..., Washington, DC, 20036, telephone (202) 833-9339, fax (202) 833-9434, Web site http://www.rtca.org... Session Closing Plenary Session Plenary Adjourns RTCA Workspace Web Tool Mid-Morning/Afternoon--Workgroup Breakout Sessions Systems Engineering Workgroup Requirements Status and Overview AV2 Overview Control and...

  18. 75 FR 2925 - Sixteenth Plenary Meeting: RTCA Special Committee 203: Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... Special Committee 203: Unmanned Aircraft Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 203: Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 203: Unmanned Aircraft Systems. DATES...

  19. 75 FR 26320 - Fourteenth Plenary Meeting, RTCA Special Committee 205/EUROCAE WG 71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-11

    ... Special Committee 205/EUROCAE WG 71: Software Considerations in Aeronautical Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 205/EUROCAE WG 71: Software... meeting of RTCA Special Committee 205/EUROCAE WG 71: Software Considerations in Aeronautical Systems...

  20. 75 FR 2924 - Thirteenth Plenary Meeting, RTCA Special Committee 205/EUROCAE WG 71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-19

    ... Special Committee 205/EUROCAE WG 71: Software Considerations in Aeronautical Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 205/EUROCAE WG 71: Software... meeting of RTCA Special Committee 205/EUROCAE WG 71: Software Considerations in Aeronautical Systems...

  1. 76 FR 50812 - Seventeenth Meeting: RTCA Special Committee 205/EUROCAE WG-71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    ... Committee 205/EUROCAE WG-71: Software Considerations in Aeronautical Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 205/EUROCAE WG-71 meeting: Software... of RTCA Special Committee 205/EUROCAE WG-71: Software Considerations in Aeronautical Systems Agenda...

  2. 76 FR 16469 - Sixteenth Meeting: RTCA Special Committee 205/EUROCAE WG-71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-23

    ... Committee 205/EUROCAE WG-71: Software Considerations in Aeronautical Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 205/EUROCAE WG-71 meeting: Software... of RTCA Special Committee 205/EUROCAE WG-71: Software Considerations in Aeronautical Systems Agenda...

  3. 76 FR 27744 - Eighty-Fifth Meeting: RTCA Special Committee 159: Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 159 meeting: Global Positioning System (GPS). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 159: Global Positioning...

  4. 75 FR 28318 - Eighty-Second Meeting: RTCA Special Committee 159: Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 159 meeting: Global Positioning System (GPS). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 159: Global Positioning...

  5. 75 FR 2581 - Eighty-First Meeting: RTCA Special Committee 159: Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-15

    ... Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 159 meeting: Global Positioning System (GPS). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 159: Global Positioning...

  6. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-18

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  7. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-23

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  8. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will...

  9. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-22

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  10. 76 FR 80447 - Eighth Meeting: RTCA Special Committee 219: Attitude and Heading Reference Systems (AHRS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-23

    ... Committee 219: Attitude and Heading Reference Systems (AHRS) AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 219: Attitude and... eighth meeting of RTCA Special Committee 219: Attitude and Heading Reference Systems (AHRS). DATES: The...

  11. 76 FR 17473 - Twelfth Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    [email protected] , and copy to [email protected] . FOR FURTHER INFORMATION CONTACT: RTCA Secretariat, 1828... site http://www.rtca.org . SUPPLEMENTARY INFORMATION: Pursuant to section 10(a)(2) of the Federal... will include: Additional Information Additional information and all the documents to be considered can...

  12. 75 FR 3959 - Fifth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 220: Automatic Flight...

  13. 75 FR 15770 - Sixth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 220: Automatic Flight...

  14. 76 FR 22163 - Tenth Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220 meeting: Automatic Flight Guidance and Control. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 220: Automatic Flight...

  15. 75 FR 54221 - RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration RTCA NextGen Advisory Committee (NAC... (NAC). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA NextGen Advisory Committee (NAC). DATES: The meeting will be held September 23, 2010, from 8:30 a.m. to 11:30 a.m...

  16. 76 FR 58078 - Thirteenth Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... Committee 214: Working Group 78: Standards for Air Traffic Data Communication Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 214: Working Group 78... public of a meeting of the RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

  17. 76 FR 50810 - Seventh Meeting: RTCA Special Committee 219: Attitude and Heading Reference System

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    ... Committee 219: Attitude and Heading Reference System AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 219 meeting: Attitude and Heading Reference System. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 219: Attitude...

  18. 76 FR 54526 - Fourth Meeting RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Committee (NAC) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: RTCA NextGen Advisory Committee (NAC). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA NextGen Advisory Committee (NAC). DATES: The meeting will be held September 29, 2011 from 9 a.m. to 4 p.m...

  19. 76 FR 3931 - Second Meeting RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... Committee (NAC) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: RTCA NextGen Advisory Committee (NAC). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA NextGen Advisory Committee (NAC). DATES: The meeting will be held February 11, 2011 from 8:30 a.m. to 1 p.m...

  20. 76 FR 22162 - Third Meeting RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Committee (NAC) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: RTCA NextGen Advisory Committee (NAC). SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA NextGen Advisory Committee (NAC). DATES: The meeting will be held May 19, 2011 from 9:30 a.m. to 2 p.m. ADDRESSES...

  1. Dynamic monitoring of GPER-mediated estrogenic effects in breast cancer associated fibroblasts: An alternative role of estrogen in mammary carcinoma development.

    PubMed

    Luo, Haojun; Liu, Manran; Luo, Shujuan; Yu, Tenghua; Wu, Chengyi; Yang, Guanglun; Tu, Gang

    2016-08-01

    Cancer associated fibroblasts (CAFs) are crucial contributors to breast cancer development. Estrogen affects mammary stroma in both physiological and pathophysiological conditions. We show here that estrogen (G-protein coupled) receptor (GPER) could be detected by immunohistochemistry in stromal fibroblasts of primary breast cancers. The presence of GPER expression was further confirmed by immunofluorescence and quantitative PCR in CAFs isolated from primary breast cancers. Based on dynamic monitoring by real time cell analyzer (RTCA) system, 17-β-estradiol (E2) as well as GPER specific agonist G1 were observed to trigger transient cell index increasing within an hour in a dosage-dependent manner in breast CAFs. In addition, E2 and G1 stimulated intracellular calcium modulation and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 within seconds and minutes in CAFs, respectively. Moreover, E2 and G1 promoted cell proliferation of breast CAFs measured by RTCA monitoring, cell viability assay and cell cycle analysis, and this promotion could be blocked by a GPER-selective antagonist G15. Interestingly, dynamic RTCA monitoring indicated that E2 increased adhesion of resuspended cells, and microscopy confirmed that E2 stimulated cell spreading. Both the adhesion and spreading were proposed to be mediated by GPER, since G1 also stimulated these effects similar to E2, and G15 reduced them. Moreover, GPER was found to mediate migration that was increased by E2 and G1 but reduced by G15 in RTCA cell migration assay and transwell assay. Accordingly, GPER mediates not only rapid actions but also slow effects including adhesion/spreading, proliferation and migration in breast CAFs. Estrogen is likely to affect tumor associated stroma and contributes to mammary carcinoma development through CAFs. Copyright © 2016. Published by Elsevier Inc.

  2. Abundance and Distribution of Diagnostic Carbon Fixation Genes in a Deep-Sea Hydrothermal Gradient Ecosystem

    NASA Astrophysics Data System (ADS)

    Blumenfeld, H. N.; Kelley, D. S.; Girguis, P. R.; Schrenk, M. O.

    2010-12-01

    The walls of deep-sea hydrothermal vent chimneys sustain steep thermal and chemical gradients resulting from the mixing of hot (350°C+) hydrothermal fluids with cold, oxygenated seawater. The chemical disequilibrium generated from this process has the potential to drive numerous chemolithoautotrophic metabolisms, many of which have been demonstrated to be operative in microbial pure cultures. In addition to the well-known Calvin Cycle, at least five additional pathways have been discovered including the Reverse Tricarboxylic Acid Cycle (rTCA), the Reductive Acetyl-CoA pathway, and the 3-hydroxyproprionate pathway. Most of the newly discovered pathways have been found in thermophilic and hyperthermophilic Bacteria and Archaea, which are the well represented in microbial diversity studies of hydrothermal chimney walls. However, to date, little is known about the environmental controls that impact various carbon fixation pathways. The overlap of limited microbial diversity with distinct habitat conditions in hydrothermal chimney walls provides an ideal setting to explore these relationships. Hydrothermal chimney walls from multiple structures recovered from the Juan de Fuca Ridge in the northeastern Pacific were sub-sampled and analyzed using PCR-based assays. Earlier work showed elevated microbial abundances in the outer portions of mature chimney walls, with varying ratios of Archaea to Bacteria from the outer to inner portions of the chimneys. Common phylotypes identified in these regions included Epsilonproteobacteria, Gammaproteobacteria, and Desulfurococcales. Total genomic DNA was extracted from mineralogically distinct niches within these structures and queried for genes coding key regulatory enzymes for each of the well studied carbon fixation pathways. Preliminary results show the occurrence of genes representing rTCA cycle (aclB) and methyl coenzyme A reductase (mcrA) - a proxy for the Reductive Acetyl-CoA Pathway within interior portion of mature hydrothermal chimneys. Ongoing analyses are aimed at quantifying the abundances of these diagnostic carbon fixation genes within the hydrothermal chimney gradients. These data are being compared to a broad array of contextual data to provide insight into the environmental and biological controls that may impact the distribution of the various carbon fixation pathways. Application of genomic approaches to the hydrothermal chimney ecosystem will provide insight into the microbial ecology of such structures and refine our ability to measure autotrophy in hydrothermal habitats sustained by chemical energy.

  3. iCELLigence real-time cell analysis system for examining the cytotoxicity of drugs to cancer cell lines

    PubMed Central

    Türker Şener, Leyla; Albeni̇z, Gürcan; Di̇nç, Bi̇rcan; Albeni̇z, Işil

    2017-01-01

    The recently developed iCELLigence™ real-time cell analyzer (RTCA) can be used for the label-free real-time monitoring of cancer cell proliferation, viability, invasion and cytotoxicity. The RTCA system uses 16-well microtiter plates with a gold microelectrode biosensor array that measures impedance when cells adhere to the microelectrodes causing an alternating current. By measuring the electric field generated in this process, the RTCA system can be used for the analysis of cell proliferation, viability, morphology and migration. The present review aimed to summarize the working method of the RTCA system, in addition to discussing the research performed using the system for various applications, including cancer drug discovery via measuring cytotoxicity. PMID:28962095

  4. Sulfide oxidation, nitrate respiration, carbon acquisition, and electron transport pathways suggested by the draft genome of a single orange Guaymas Basin Beggiatoa (Cand. Maribeggiatoa) sp. filament.

    PubMed

    MacGregor, Barbara J; Biddle, Jennifer F; Harbort, Christopher; Matthysse, Ann G; Teske, Andreas

    2013-09-01

    A near-complete draft genome has been obtained for a single vacuolated orange Beggiatoa (Cand. Maribeggiatoa) filament from a Guaymas Basin seafloor microbial mat, the third relatively complete sequence for the Beggiatoaceae. Possible pathways for sulfide oxidation; nitrate respiration; inorganic carbon fixation by both Type II RuBisCO and the reductive tricarboxylic acid cycle; acetate and possibly formate uptake; and energy-generating electron transport via both oxidative phosphorylation and the Rnf complex are discussed here. A role in nitrite reduction is suggested for an abundant orange cytochrome produced by the Guaymas strain; this has a possible homolog in Beggiatoa (Cand. Isobeggiatoa) sp. PS, isolated from marine harbor sediment, but not Beggiatoa alba B18LD, isolated from a freshwater rice field ditch. Inferred phylogenies for the Calvin-Benson-Bassham (CBB) cycle and the reductive (rTCA) and oxidative (TCA) tricarboxylic acid cycles suggest that genes encoding succinate dehydrogenase and enzymes for carboxylation and/or decarboxylation steps (including RuBisCO) may have been introduced to (or exported from) one or more of the three genomes by horizontal transfer, sometimes by different routes. Sequences from the two marine strains are generally more similar to each other than to sequences from the freshwater strain, except in the case of RuBisCO: only the Guaymas strain encodes a Type II enzyme, which (where studied) discriminates less against oxygen than do Type I RuBisCOs. Genes subject to horizontal transfer may represent key steps for adaptation to factors such as oxygen and carbon dioxide concentration, organic carbon availability, and environmental variability. © 2013.

  5. 76 FR 15039 - RTCA Government/Industry NextGen Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... air transportation concepts, requirements, operational capabilities, and the associated use of... Management System. RTCA provides the following two categories of recommendations to the FAA: Broad gauged...

  6. Polynucleotide 3′-terminal Phosphate Modifications by RNA and DNA Ligases

    PubMed Central

    Zhelkovsky, Alexander M.; McReynolds, Larry A.

    2014-01-01

    RNA and DNA ligases catalyze the formation of a phosphodiester bond between the 5′-phosphate and 3′-hydroxyl ends of nucleic acids. In this work, we describe the ability of the thermophilic RNA ligase MthRnl from Methanobacterium thermoautotrophicum to recognize and modify the 3′-terminal phosphate of RNA and single-stranded DNA (ssDNA). This ligase can use an RNA 3′p substrate to generate an RNA 2′,3′-cyclic phosphate or convert DNA3′p to ssDNA3′pp5′A. An RNA ligase from the Thermus scotoductus bacteriophage TS2126 and a predicted T4 Rnl1-like protein from Thermovibrio ammonificans, TVa, were also able to adenylate ssDNA 3′p. These modifications of RNA and DNA 3′-phosphates are similar to the activities of RtcA, an RNA 3′-phosphate cyclase. The initial step involves adenylation of the enzyme by ATP, which is then transferred to either RNA 3′p or DNA 3′p to generate the adenylated intermediate. For RNA 3′pp5′A, the third step involves attack of the adjacent 2′ hydroxyl to generate the RNA 2′,3′-cyclic phosphate. These steps are analogous to those in classical 5′ phosphate ligation. MthRnl and TS2126 RNA ligases were not able to modify a 3′p in nicked double-stranded DNA. However, T4 DNA ligase and RtcA can use 3′-phosphorylated nicks in double-stranded DNA to produce a 3′-adenylated product. These 3′-terminal phosphate-adenylated intermediates are substrates for deadenylation by yeast 5′Deadenylase. Our findings that classic ligases can duplicate the adenylation and phosphate cyclization activity of RtcA suggests that they have an essential role in metabolism of nucleic acids with 3′-terminal phosphates. PMID:25324547

  7. 75 FR 49550 - Fifth Meeting: RTCA Special Committee 219: Attitude and Heading Reference System (AHRS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... 219: Attitude and Heading Reference System (AHRS) AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 219: Attitude and Heading... 49551

  8. 76 FR 2745 - Federal Aviation Administration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-14

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Eighty-Fourth Meeting: RTCA Special Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 159 meeting: Global Positioning System (GPS). SUMMARY: The FAA is...

  9. 78 FR 40264 - First Meeting: RTCA Tactical Operations Committee (TOC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-03

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration First Meeting: RTCA Tactical Operations Committee (TOC) AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation..., Leadership Anticipated Issues for TOC consideration and action at the next meeting. Any Other Business...

  10. 78 FR 16757 - First Meeting: RTCA Tactical Operations Committee (TOC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-18

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration First Meeting: RTCA Tactical Operations Committee (TOC) AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation... FAA Task Groups Discussion Anticipated Issues for TOC consideration and action at the next meeting...

  11. 76 FR 22162 - Sixteenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... meeting held January 18-21, 2011. Report on the PMC/ICC Action on TOR. RTCA Specific Publication Progress... Advisory Committee. [FR Doc. 2011-9489 Filed 4-19-11; 8:45 am] BILLING CODE 4910-13-P ...

  12. 78 FR 38093 - Seventh Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... Committee 226, Audio Systems and Equipment AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 226, Audio Systems and Equipment. SUMMARY... 226, Audio Systems and Equipment [[Page 38094

  13. 75 FR 55847 - Fourteenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-14

    ..., (RTCA Paper No. 137-10/SC216-029). Report on the PMC/ICC action on TOR: Publication Progress and Update... Advisory Committee. [FR Doc. 2010-22879 Filed 9-13-10; 8:45 am] BILLING CODE 4910-13-P ...

  14. 75 FR 54421 - Sixth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-07

    ... 223: Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 223: Airport Surface Wireless... Committee 223: Airport Surface Wireless Communications. DATES: The meeting will be held September 28-30...

  15. 76 FR 79755 - First Meeting: RTCA Special Committee 226 Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-22

    ... Administrative Remarks Introductions RTCA Overview Audio Systems and Equipment--Background and History Agenda..., Discussion, Recommendations and Assignment of Responsibilities Other Business Establish Agenda for Next..., Manager, Business Operations Branch, Federal Aviation Administration. [FR Doc. 2011-32863 Filed 12-21-11...

  16. 75 FR 20671 - Seventieth Meeting: RTCA Special Committee 147: Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-20

    ... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... RTCA Special Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision...

  17. 76 FR 6179 - Eighth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... Committee 223: Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 223: Airport Surface Wireless... Committee 223: Airport Surface Wireless Communications. DATES: The meeting will be held February 22-23, 2011...

  18. 75 FR 66423 - Seventh Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-28

    ... Committee 223: Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 223: Airport Surface Wireless... Committee 223: Airport Surface Wireless Communications. DATES: The meeting will be held November 16-17, 2010...

  19. 78 FR 33145 - Meeting: RTCA Special Committee 223, Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-03

    ..., Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 223, Airport Surface Wireless... Committee 223, Airport Surface Wireless Communications. DATES: The meeting will be held June 26-28, 2013...

  20. 76 FR 59481 - Ninth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... Control Systems (Update to DO-230B): Agenda October 20, 2011 Welcome/Introductions/Administrative Remarks... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY...

  1. 76 FR 50811 - Eighth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    ... Control Systems (Update to DO-230B): Agenda September 15, 2011 Welcome/Introductions/Administrative... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY...

  2. 75 FR 29811 - 21st Meeting: RTCA Special Committee 206: EUROCAE WG 76 Plenary: AIS and MET Data Link Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ... Aeronautique, 8, Avenue Roland Garros, F-33698 Merignac Cedex, France. Contact Person: Stephane Dubet, Phone: 33-5-57 92 57 81, Cell Phone: 33-6-10 74 56 00. FOR FURTHER INFORMATION CONTACT: RTCA Secretariat...

  3. 76 FR 11846 - Seventy-second Meeting: RTCA Special Committee 147: Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Committee 147 meeting: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance... RTCA Special Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision...

  4. 75 FR 52590 - Seventy-First Meeting: RTCA Special Committee 147: Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... RTCA Special Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision...

  5. 76 FR 58077 - Seventy-Third Meeting: RTCA Special Committee 147: Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Committee 147 meeting: Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance... RTCA Special Committee 147: Minimum Operational Performance Standards for Traffic Alert and Collision...

  6. 76 FR 63987 - Fifty-Fifth Meeting: RTCA Special Committee 186: Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-14

    ... Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 186: Automatic Dependent Surveillance Broadcast... Special Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B). DATES: The meeting will be...

  7. 76 FR 3932 - Fifty-Third Meeting: RTCA Special Committee 186: Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 186: Automatic Dependent Surveillance--Broadcast... Special Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B). DATES: The meeting will be...

  8. 76 FR 22160 - Fifty-Fourth Meeting: RTCA Special Committee 186: Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 186: Automatic Dependent Surveillance--Broadcast... Special Committee 186: Automatic Dependent Surveillance--Broadcast (ADS-B). DATES: The meeting will be...

  9. Analysis performed in support of the Ad-Hoc Working Group of RTCA SC-159 on RAIM/FDE issues

    DOT National Transportation Integrated Search

    2002-01-01

    In 1999, the FAA requested that RTCA SC-159 address one of the recommendations from the study performed by the Johns Hopkins University (JHU) Applied Physics Lab (APL) on the use of GPS and augmented GPS for aviation applications. This recommendation...

  10. 77 FR 2342 - Seventeenth Meeting: RTCA Special Committee 213, Enhanced Flight Vision/Synthetic Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... Committee 213, Enhanced Flight Vision/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation..., Enhanced Flight Vision/ Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing this notice to advise the public of the seventeenth meeting of RTCA Special Committee 213, Enhanced Flight Vision...

  11. 75 FR 14483 - Third Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-25

    ... 223: Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 223: Airport Surface Wireless Communications meeting. SUMMARY...: Airport Surface Wireless Communications. DATES: The meeting will be held April 13-14, 2010 from 9 a.m.-5 p...

  12. 77 FR 55894 - Thirteenth Meeting: RTCA Special Committee 223, Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Committee 223, Airport Surface Wireless Communications AGENCY: Federal Aviation Administration (FAA), U.S... Wireless Communications. SUMMARY: The FAA is issuing this notice to advise the public of the thirteenth meeting of the RTCA Special Committee 223, Airport Surface Wireless Communications. DATES: The meeting...

  13. 75 FR 71790 - Second Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held December 9, 2010...

  14. 75 FR 80886 - Third Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held January 13, 2011...

  15. 76 FR 38742 - Seventh Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... Control Systems (Update to DO-230B): Agenda July 15, 2011 Welcome/Introductions/Administrative Remarks... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to...

  16. 76 FR 9632 - Fifth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-18

    ... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held March 10, 2011, from...

  17. 76 FR 3931 - Fourth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 Meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held February 8, 2011...

  18. 78 FR 69928 - First Meeting: RTCA Special Committee 228-Minimum Operational Performance Standards for Unmanned...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-21

    ... 228--Minimum Operational Performance Standards for Unmanned Aircraft Systems AGENCY: Federal Aviation...--Minimum Operational Performance Standards for Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 228--Minimum Operational Performance...

  19. 78 FR 38093 - First Meeting: RTCA Special Committee 228-Minimum Operational Performance Standards for Unmanned...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... 228--Minimum Operational Performance Standards for Unmanned Aircraft Systems AGENCY: Federal Aviation...--Minimum Operational Performance Standards for Unmanned Aircraft Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 228--Minimum Operational Performance...

  20. 75 FR 80886 - Ninth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The FAA is... for a Special Committee 220: Automatic Flight Guidance and Control meeting. The agenda will include...

  1. 77 FR 56254 - 89th Meeting: RTCA Special Committee 159, Global Positioning Systems (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... 159, Global Positioning Systems (GPS). SUMMARY: The FAA is issuing this notice to advise the public of the eighty-ninth meeting of the RTCA Special Committee 159, Global Positioning Systems (GPS). DATES... 159, Global Positioning Systems (GPS) AGENCY: Federal Aviation Administration (FAA), U.S. Department...

  2. 78 FR 13396 - 90th Meeting: RTCA Special Committee 159, Global Positioning Systems (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ... 159, Global Positioning Systems (GPS) SUMMARY: The FAA is issuing this notice to advise the public of the eighty-ninth meeting of the RTCA Special Committee 159, Global Positioning Systems (GPS). DATES... 159, Global Positioning Systems (GPS) AGENCY: Federal Aviation Administration (FAA), U.S. Department...

  3. 76 FR 33022 - Eighty-Sixth Meeting: RTCA Special Committee 159: Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

    ... Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 159 meeting: Global Positioning System (GPS). SUMMARY: The FAA is...), notice is hereby given for a Special Committee 159: Global Positioning System (GPS) meeting. The agenda...

  4. 75 FR 61819 - First Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-06

    ... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held November 2, 2010...

  5. 76 FR 16470 - Sixth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-23

    ... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems DATES: The meeting will be held April 13, 2011, from...

  6. 77 FR 12105 - 56th Meeting: RTCA Special Committee 186, Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... Existing Traffic Safety Nets EUORCAE WG51 TSAA Perpective Flight-deck Interval Management (FIM)--Status... Only Agenda Items Document Approval: DO-xxx--Minimum Aviation System Performance Standards (MASPS) for... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 56th Meeting: RTCA Special Committee...

  7. 76 FR 66350 - Eighth Meeting: RTCA Special Committee 222 Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ... Committee 222 Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation..., Inmarsat Aeronautical Mobile Satellite (Route) Services meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite...

  8. 77 FR 30046 - Ninth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-21

    ... 222, Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation Administration..., Inmarsat Aeronautical Mobile Satellite (Route) Services. SUMMARY: The FAA is issuing this notice to advise the public of the Ninth meeting of RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite...

  9. 75 FR 9016 - Fifty-Fifth Meeting, RTCA Special Committee 135: Environmental Conditions and Test Procedures for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... Committee 135: Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation... Procedures for Airborne Equipment meeting. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 135: Environmental Conditions and Test Procedures for Airborne Equipment...

  10. 75 FR 59326 - Eighth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The... Flight Guidance and Control. DATES: The meeting will be held October 12-14, 2010. October 12th and 13th...

  11. 76 FR 50809 - Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Correction of Notice of RTCA Special Committee 220 meeting: Automatic Flight Guidance and Control...: Automatic Flight Guidance and Control DATES: The meeting will be held September 13-15, 2011, from 9 a.m. to...

  12. 78 FR 18416 - Sixth Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ... 226, Audio Systems and Equipment AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 226, Audio Systems and Equipment. SUMMARY... 226, Audio Systems and Equipment. DATES: The meeting will be held April 15-17, 2013 from 9:00 a.m.-5...

  13. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-30

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the seventeenth meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  14. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-24

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  15. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the nineteenth meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  16. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the eleventh meeting of RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held...

  17. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty first meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...

  18. 77 FR 25525 - Thirteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-30

    ... Committee 224, Airport Security Access Control Systems. AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the thirteenth meeting of RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will be...

  19. 76 FR 11847 - Thirteenth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... Special Committee 213: EUROCAE WG- 79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS... Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems... Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS...

  20. 76 FR 20437 - Fourteenth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ... Special Committee 213: EUROCAE WG- 79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS... Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems... Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS...

  1. 77 FR 15448 - Twelfth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twelfth meeting of RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will be...

  2. UAS Integration in the NAS Project Overview: RTCA SC-228 Plenary DAA Working Group 5

    NASA Technical Reports Server (NTRS)

    Randall, Debra K.

    2014-01-01

    The presentation is intended to allow the public to know and understand NASA's plans for integrated test to allow them the opportunity to provide feedback and suggestions. The integrated testing will support verification and validation of the RTCA SC-228 UAS minimum operation performance standard requirements.

  3. 76 FR 66350 - Eighteenth Meeting: RTCA Special Committee 205/EUROCAE WG-71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-26

    ... Committee 205/EUROCAE WG-71: Software Considerations in Aeronautical Systems AGENCY: Federal Aviation.../EUROCAE WG-71 meeting: Software Considerations in Aeronautical Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 205/EUROCAE WG-71: Software...

  4. 76 FR 22161 - Second Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes AGENCY: Federal... Lithium Batteries and Battery Systems--Small and Medium Sizes. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery...

  5. 76 FR 70531 - Fifth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems-Small...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal Aviation..., Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 225, Rechargeable Lithium Battery and...

  6. 76 FR 6180 - First Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes AGENCY: Federal... Lithium Batteries and Battery Systems--Small and Medium Sizes. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery...

  7. 76 FR 54527 - Fourth Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... Committee 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes AGENCY: Federal... Lithium Batteries and Battery Systems--Small and Medium Sizes. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery...

  8. 76 FR 38741 - Third Meeting: RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... 225: Rechargeable Lithium Batteries and Battery Systems--Small and Medium Sizes AGENCY: Federal... Lithium Batteries and Battery Systems--Small and Medium Sizes. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 225: Rechargeable Lithium Batteries and Battery...

  9. 75 FR 44306 - Fifth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ..., Introductions, Administrative Remarks, Approve/ Review Meeting 4 Summary, RTCA Paper No. 099-10/SC223-009). Welcome from NASA Glenn Research Center Management: Dr. Gary Seng. Special Committee Leadership... from 9 a.m.-5 p.m. ADDRESSES: The meeting will be held at the NASA Glenn Research Center, 21000...

  10. 77 FR 46147 - 57th Meeting: RTCA Special Committee 186, Automatic Dependent Surveillance Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-02

    ... 186, Automatic Dependent Surveillance Broadcast (ADS-B) AGENCY: Federal Aviation Administration (FAA..., Automatic Dependent Surveillance Broadcast (ADS-B). SUMMARY: The FAA is issuing this notice to advise the public of the 57th meeting of RTCA Special Committee 186, Automatic Dependent Surveillance Broadcast (ADS...

  11. 76 FR 67019 - Tenth Meeting: RTCA Special Committee 224, Airport Security Access Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... 224, Airport Security Access Control AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 224, Airport Security Access Control. SUMMARY: The... (Pub. L. 92-463, 5 U.S.C., App.), notice is hereby given for a Special Committee 224, Airport Security...

  12. 76 FR 38742 - Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220 Meeting: Automatic Flight Guidance and Control. SUMMARY: The... Flight Guidance and Control DATES: The meeting will be held August 9-11, 2011, from 9 a.m. to 5 p.m...

  13. 75 FR 36471 - Seventh Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ... Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220: Automatic Flight Guidance and Control meeting. SUMMARY: The... Flight Guidance and Control. DATES: The meeting will be held July 13-15, 2010. July 13th and 14th from 9...

  14. 78 FR 57673 - Eighth Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ... Committee 226, Audio Systems and Equipment AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 226, Audio Systems and Equipment. SUMMARY... Committee 226, Audio Systems and Equipment. DATES: The meeting will be held October 8-10, 2012 from 9:00 a.m...

  15. 77 FR 37732 - Fourteenth Meeting: RTCA Special Committee 224, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... Committee 224, Audio Systems and Equipment AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Audio Systems and Equipment. SUMMARY... Committee 224, Audio Systems and Equipment. DATES: The meeting will be held July 11, 2012, from 10 a.m.-4 p...

  16. 77 FR 12106 - 88th Meeting: RTCA Special Committee 159, Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... 159, Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 159, Global Positioning System (GPS). SUMMARY: The..., Global Positioning System (GPS). DATES: The meeting will be held March 13-16, 2012, from 9 a.m.-4:30 p.m...

  17. 75 FR 10552 - Sixth Meeting-RTCA Special Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-08

    ... 217: Joint With EUROCAE WG- 44 Terrain and Airport Mapping Databases AGENCY: Federal Aviation... Airport Mapping Databases. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 217: Joint with EUROCAE WG-44 Terrain and Airport Mapping Databases. DATES: The...

  18. 76 FR 27744 - Eighth Meeting-RTCA Special Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping Databases AGENCY: Federal Aviation... Airport Mapping Databases. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 217: Joint with EUROCAE WG-44 Terrain and Airport Mapping Databases. DATES: The...

  19. 76 FR 54527 - Ninth Meeting-RTCA Special Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-01

    ... 217: Joint With EUROCAE WG- 44 Terrain and Airport Mapping Databases AGENCY: Federal Aviation... Airport Mapping Databases. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 217: Joint with EUROCAE WG-44 Terrain and Airport Mapping Databases. DATES: The...

  20. 76 FR 6179 - Eighth Meeting-RTCA Special Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping Databases AGENCY: Federal Aviation... Airport Mapping Databases. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 217: Joint with EUROCAE WG-44 Terrain and Airport Mapping Databases. DATES: The...

  1. 77 FR 2343 - Eighteenth Meeting: RTCA Special Committee 216: Aeronautical Systems Security (Joint Meeting With...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... advise the public of the eighteenth meeting of RTCA Special Committee 216: Aeronautical Systems Security... Agenda Overview and Approval Split Plenary Session (9:15 a.m.--12 p.m.) SC 216 Review of the Summary of....--12 p.m.) WG-72 Introduction, Report about publications and relations EUROCAE Document Discussions, e...

  2. Application of RNA Stable Isotope Probing (SIP) to Link Community Activity with Microorganisms Responsible for Autotrophy in the Subseafloor at Axial Seamount

    NASA Astrophysics Data System (ADS)

    Huber, J. A.; Fortunato, C. S.

    2014-12-01

    The global ocean comprises the Earth's largest biome, with microorganisms playing a dominant biogeochemical role. However, the potential for production of new microbial biomass within the subseafloor is rarely considered in traditional oceanographic paradigms of carbon cycling or microbial food webs. In this study, we used RNA Stable Isotope Probing (RNA SIP) to determine the microbial community composition and genetic repertoire of active subseafloor autotrophs in warm venting fluids from Axial Seamount. RNA is a responsive biomarker because it is a reflection of cellular activity independent of replication, and RNA SIP thus provides access to both the function of a microbial community and the phylogeny of the organisms accountable for key functions. Diffuse fluids were incubated shipboard at 30°C, 55°C, and 80°C with 13DIC and H2. Metatranscriptomic sequencing of both the enriched and non-enriched RNA was carried out from 13C and 12C controls. In addition, filtered fluid samples were preserved in situ for comparative meta -transcriptomic and -genomic analyses. Diverse lineages of bacteria and archaea and accompanying metabolisms were detected in situ, but RNA SIP results show dominance of three different groups of autotrophs active under each experimental condition. At 30°C, members of the Sulfurimonas genus dominated, with genes for hydrogen oxidation, nitrate reduction, and carbon fixation via the rTCA cycle highly expressed. At 55°C, both Caminibacter and Nautilia transcripts were detected for rTCA cycle, hydrogen oxidation, and nitrate reduction. At 80°C, transcripts for hydrogenotrophic methanogenesis mediated by members of Methanocaldococcus were detected. These results suggest the subseafloor hosts various anaerobic chemolithoautotrophs that span a wide temperature range, with hydrogen playing a key role in microbial metabolism. Complementary experiments are currently being carried out on the seafloor with a novel in situ incubator unit to provide further insights to primary productivity in the subseafloor.

  3. 77 FR 29750 - Fifteenth Meeting: RTCA Special Committee 214, Joint With EUROCAE WG-78, Standards for Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    [email protected] , or Tel.: +31 43 366 1396. FOR FURTHER INFORMATION CONTACT: The RTCA Secretariat, 1150 18th....int no later than May 21, 2012 with the following security information: Last Name/ First name... cargo hangers-- first flight at between 06:00 and 06:15) SUPPLEMENTARY INFORMATION: Pursuant to section...

  4. 75 FR 66828 - Eleventh Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-29

    .... Now TORS(OCL/DSC, update ED 154/Doxxx, * * *). Outcome FRAC/consultation DO306/ED 122 and Publication... TORs and Work Plan. Review of Position Papers and Contributions. 13:30-17:00: Plenary Session.... Robert L. Bostiga, RTCA Advisory Committee. [FR Doc. 2010-27260 Filed 10-28-10; 8:45 am] BILLING CODE...

  5. 78 FR 8684 - Twelfth Meeting: RTCA Special Committee 222, Inmarsat AMS(R)S

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... Committee 222, Inmarsat AMS(R)S AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 222, Inmarsat AMS(R)S. SUMMARY: The FAA is..., Inmarsat AMS(R)S. DATES: The meeting will be held February 20, 2013, from 1:00 p.m.--4:00 p.m. ADDRESSES...

  6. 78 FR 61446 - Fourteenth Meeting: RTCA Special Committee 222, Inmarsat AMS(R)S

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-03

    ... Committee 222, Inmarsat AMS(R)S AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 222, Inmarsat AMS(R)S. SUMMARY: The FAA is..., Inmarsat AMS(R)S DATES: The meeting will be held November 19, 2013 from 9:00 a.m.-5:00 p.m. ADDRESSES: The...

  7. First Comparative Analysis of the Community Structures and Carbon Metabolic Pathways of the Bacteria Associated with Alvinocaris longirostris in a Hydrothermal Vent of Okinawa Trough.

    PubMed

    Sun, Qing-Lei; Zeng, Zhi-Gang; Chen, Shuai; Sun, Li

    2016-01-01

    Alvinocaris longirostris is a species of shrimp existing in the hydrothermal fields of Okinawa Trough. To date the structure and function of the microbial community associated with A. longirostris are essentially unknown. In this study, by employment of the techniques of high through-put sequencing and clone library construction and analysis, we compared for the first time the community structures and metabolic profiles of microbes associated with the gill and gut of A. longirostris in a hydrothermal field of Okinawa Trough. Fourteen phyla were detected in the gill and gut communities, of which 11 phyla were shared by both tissues. Proteobacteria made up a substantial proportion in both tissues, while Firmicutes was abundant only in gut. Although gill and gut communities were similar in bacterial diversities, the bacterial community structures in these two tissues were significantly different. Further, we discovered for the first time the existence in the gill and gut communities of A. longirostris the genes (cbbM and aclB) encoding the key enzymes of Calvin-Benson-Bassham (CBB) cycle and the reductive tricarboxylic acid (rTCA) cycle, and that both cbbM and aclB were significantly more abundant in gill than in gut. Taken together, these results provide the first evidence that at least two carbon fixation pathways are present in both the gill and the gut communities of A. longirostris, and that the communities in different tissues likely differ in autotrophic productivity.

  8. Metagenomic analysis reveals a green sulfur bacterium as a potential coral symbiont.

    PubMed

    Cai, Lin; Zhou, Guowei; Tian, Ren-Mao; Tong, Haoya; Zhang, Weipeng; Sun, Jin; Ding, Wei; Wong, Yue Him; Xie, James Y; Qiu, Jian-Wen; Liu, Sheng; Huang, Hui; Qian, Pei-Yuan

    2017-08-24

    Coral reefs are ecologically significant habitats. Coral-algal symbiosis confers ecological success on coral reefs and coral-microbial symbiosis is also vital to coral reefs. However, current understanding of coral-microbial symbiosis on a genomic scale is largely unknown. Here we report a potential microbial symbiont in corals revealed by metagenomics-based genomic study. Microbial cells in coral were enriched for metagenomic analysis and a high-quality draft genome of "Candidatus Prosthecochloris korallensis" was recovered by metagenome assembly and genome binning. Phylogenetic analysis shows "Ca. P. korallensis" belongs to the Prosthecochloris clade and is clustered with two Prosthecochloris clones derived from Caribbean corals. Genomic analysis reveals "Ca. P. korallensis" has potentially important ecological functions including anoxygenic photosynthesis, carbon fixation via the reductive tricarboxylic acid (rTCA) cycle, nitrogen fixation, and sulfur oxidization. Core metabolic pathway analysis suggests "Ca. P. korallensis" is a green sulfur bacterium capable of photoautotrophy or mixotrophy. Potential host-microbial interaction reveals a symbiotic relationship: "Ca. P. korallensis" might provide organic and nitrogenous nutrients to its host and detoxify sulfide for the host; the host might provide "Ca. P. korallensis" with an anaerobic environment for survival, carbon dioxide and acetate for growth, and hydrogen sulfide as an electron donor for photosynthesis.

  9. Structure of RNA 3′-phosphate cyclase bound to substrate RNA

    PubMed Central

    Desai, Kevin K.; Bingman, Craig A.; Cheng, Chin L.; Phillips, George N.

    2014-01-01

    RNA 3′-phosphate cyclase (RtcA) catalyzes the ATP-dependent cyclization of a 3′-phosphate to form a 2′,3′-cyclic phosphate at RNA termini. Cyclization proceeds through RtcA–AMP and RNA(3′)pp(5′)A covalent intermediates, which are analogous to intermediates formed during catalysis by the tRNA ligase RtcB. Here we present a crystal structure of Pyrococcus horikoshii RtcA in complex with a 3′-phosphate terminated RNA and adenosine in the AMP-binding pocket. Our data reveal that RtcA recognizes substrate RNA by ensuring that the terminal 3′-phosphate makes a large contribution to RNA binding. Furthermore, the RNA 3′-phosphate is poised for in-line attack on the P–N bond that links the phosphorous atom of AMP to Nε of His307. Thus, we provide the first insights into RNA 3′-phosphate termini recognition and the mechanism of 3′-phosphate activation by an Rtc enzyme. PMID:25161314

  10. Digital avionics susceptibility to high energy radio frequency fields

    NASA Astrophysics Data System (ADS)

    Larsen, William E.

    Generally, noncritical avionic systems for transport category aircraft have been designed to meet radio frequency (RF) susceptibility requirements set forth in RTCA DO 160B, environmental conditions and test procedures for airborne equipment. Section 20 of this document controls the electromagnetic interference (EMI) hardening for avionics equipment to levels of 1 and 2 V/m. Currently, US equipment manufacturers are designing flight-critical fly-by-wire avionics to a much higher level. The US Federal Aviation Administration (FAA) has requested that the RTCA SC-135 high-energy radio frequency (HERF) working group develop appropriate testing procedures for section 20 of RTCA DO 160B for radiated and conducted susceptibility at the box and systems level. The FAA has also requested the SAE AE4R committee to address installed systems testing, airframe shielding effects and RF environment monitoring. Emitters of interest include radar (ground, ship, and aircraft) commercial broadcast and TV station, mobile communication, and other transmitters that could possibly affect commercial aircraft.

  11. Robust real-time cell analysis method for determining viral infectious titers during development of a viral vaccine production process.

    PubMed

    Charretier, Cédric; Saulnier, Aure; Benair, Loïc; Armanet, Corinne; Bassard, Isabelle; Daulon, Sandra; Bernigaud, Bertrand; Rodrigues de Sousa, Emanuel; Gonthier, Clémence; Zorn, Edouard; Vetter, Emmanuelle; Saintpierre, Claire; Riou, Patrice; Gaillac, David

    2018-02-01

    The classical cell-culture methods, such as cell culture infectious dose 50% (CCID 50 ) assays, are time-consuming, end-point assays currently used during the development of a viral vaccine production process to measure viral infectious titers. However, they are not suitable for handling the large number of tests required for high-throughput and large-scale screening analyses. Impedance-based bio-sensing techniques used in real-time cell analysis (RTCA) to assess cell layer biological status in vitro, provide real-time data. In this proof-of-concept study, we assessed the correlation between the results from CCID 50 and RTCA assays and compared time and costs using monovalent and tetravalent chimeric yellow fever dengue (CYD) vaccine strains. For the RTCA assay, Vero cells were infected with the CYD sample and real-time impedance was recorded, using the dimensionless cell index (CI). The CI peaked just after infection and decreased as the viral cytopathic effect occurred in a dose-dependent manner. The time to the median CI (CIT med ) was correlated with viral titers determined by CCID 50 over a range of about 4-5log 10 CCID 50 /ml. This in-house RTCA virus-titration assay was shown to be a robust method for determining real-time viral infectious titers, and could be an alternative to the classical CCID 50 assay during the development of viral vaccine production process. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Towards FAA Certification of UAVs

    NASA Technical Reports Server (NTRS)

    Nelson, Stacy

    2003-01-01

    As of June 30, 2003, all Unmanned Aerial Vehicles (UAV), no matter how small, must adhere to the same FAA regulations as human-piloted aircraft. These regulations include certification for flying in controlled airspace and certification of flight software based on RTCA DO-178B. This paper provides an overview of the steps necessary to obtain certification, as well as a discussion about the challenges UAV's face when trying to meet these requirements. It is divided into two parts: 1) Certifications for Flying in Controlled Airspace; 2) Certification of Flight Software per RTCA DO-178B.

  13. Unmanned aircraft systems integration into the national airspace

    NASA Astrophysics Data System (ADS)

    Wolf, H. G.

    This paper examines the Federal Aviation Administration (FAA) Regulation Roadmap as set forth in the FAA Modernization and Reform Act of 2012 as well as the evolutionary process of relative legal framework. The paper will also explore the role of industry stakeholders and semi-governmental, advisory groups such as the RTCA SC-203 to show the involvement of non-governmental organizations. Leveraging the author's involvement with RTCA on the Safety Work Group of Special Committee 203, two processes within the context of safety will be explained and problems identified.

  14. Autonomous Aircraft Operations using RTCA Guidelines for Airborne Conflict Management

    NASA Technical Reports Server (NTRS)

    Krishnamurthy, Karthik; Wing, David J.; Barmore, Bryan E.; Barhydt, Richard; Palmer, Michael T.; Johnson, Edward J.; Ballin, Mark G.; Eischeid, Todd M.

    2003-01-01

    A human-in-the-loop experiment was performed at the NASA Langley Research Center to study the feasibility of DAG-TM autonomous aircraft operations in highly constrained airspace. The airspace was constrained by a pair of special-use airspace (SUA) regions on either side of the pilot's planned route. Traffic flow management (TFM) constraints were imposed as a required time of arrival and crossing altitude at an en route fix. Key guidelines from the RTCA Airborne Conflict Management (ACM) concept were applied to autonomous aircraft operations for this experiment. These concepts included the RTCA ACM definitions of distinct conflict detection and collision avoidance zones, and the use of a graded system of conflict alerts for the flight crew. Three studies were conducted in the course of the experiment. The first study investigated the effect of hazard proximity upon pilot ability to meet constraints and solve conflict situations. The second study investigated pilot use of the airborne tools when faced with an unexpected loss of separation (LOS). The third study explored pilot interactions in an over-constrained conflict situation, with and without priority rules dictating who should move first. Detailed results from these studies were presented at the 5th USA/Europe Air Traffic Management R&D Seminar (ATM2003). This overview paper focuses on the integration of the RTCA ACM concept into autonomous aircraft operations in highly constrained situations, and provides an overview of the results presented at the ATM2003 seminar. These results, together with previously reported studies, continue to support the feasibility of autonomous aircraft operations.

  15. Coupled RNA-SIP and metatranscriptomics of active chemolithoautotrophic communities at a deep-sea hydrothermal vent.

    PubMed

    Fortunato, Caroline S; Huber, Julie A

    2016-08-01

    The chemolithoautotrophic microbial community of the rocky subseafloor potentially provides a large amount of organic carbon to the deep ocean, yet our understanding of the activity and metabolic complexity of subseafloor organisms remains poorly described. A combination of metagenomic, metatranscriptomic, and RNA stable isotope probing (RNA-SIP) analyses were used to identify the metabolic potential, expression patterns, and active autotrophic bacteria and archaea and their pathways present in low-temperature hydrothermal fluids from Axial Seamount, an active submarine volcano. Metagenomic and metatranscriptomic results showed the presence of genes and transcripts for sulfur, hydrogen, and ammonium oxidation, oxygen respiration, denitrification, and methanogenesis, as well as multiple carbon fixation pathways. In RNA-SIP experiments across a range of temperatures under reducing conditions, the enriched (13)C fractions showed differences in taxonomic and functional diversity. At 30 °C and 55 °C, Epsilonproteobacteria were dominant, oxidizing hydrogen and primarily reducing nitrate. Methanogenic archaea were also present at 55 °C, and were the only autotrophs present at 80 °C. Correspondingly, the predominant CO2 fixation pathways changed from the reductive tricarboxylic acid (rTCA) cycle to the reductive acetyl-CoA pathway with increasing temperature. By coupling RNA-SIP with meta-omics, this study demonstrates the presence and activity of distinct chemolithoautotrophic communities across a thermal gradient of a deep-sea hydrothermal vent.

  16. Effect of surface passivation on corrosion resistance and antibacterial properties of Cu-bearing 316L stainless steel

    NASA Astrophysics Data System (ADS)

    Zhao, Jinlong; Xu, Dake; Shahzad, M. Babar; Kang, Qiang; Sun, Ying; Sun, Ziqing; Zhang, Shuyuan; Ren, Ling; Yang, Chunguang; Yang, Ke

    2016-11-01

    The resistance for pitting corrosion, passive film stability and antibacterial performance of 316L-Cu SS passivated by nitric acid solution containing certain concentration of copper sulfate, were studied by electrochemical cyclic polarization, electrochemical impedance spectroscopy (EIS) and co-culture with bacteria. Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze the Cu2+ ions release from 316L-Cu SS surface. XPS analysis proved that the enrichment of CuO, Cr2O3 and Cr(OH)3 on the surface of specimen could simultaneously guarantee a better corrosion resistance and stable antibacterial properties. The biocompatibility evaluation determined by RTCA assay also indicated that the 316L-Cu SS after antibacterial passivation was completely biocompatible.

  17. Progress on the Development of the UAS C2 Link and Supporting Spectrum - from LOS to BLOS

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Griner, James H.; Bishop, William D.; Matolak, David W.; Wilson, Jeffrey D.

    2017-01-01

    In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System, the control and non-payload communications (CNPC) link connecting the ground-based pilot with the unmanned aircraft must be highly reliable and robust, based upon standards that enable certification. Both line-of-sight (LOS) links using terrestrial-based communications and beyond-line-of-sight (BLOS) links using satellite communications are required to support UAS operations. The development of standards has been undertaken by RTCA Special Committee 228 (SC-228), with supporting technical data developed by NASA under the UAS in the National Airspace (NAS) Project. As a result of this work minimum operational performance standards (MOPS) have been completed and published for the LOS CNPC system. The second phase of work, for both NASA and RTCA involves the BLOS CNPC systems. The development of technical data to support MOPS development for UAS BLOS satellite-based CNPC links has now been initiated by NASA, and RTCA SC-228 has organized itself to begin the MOPS development process. This paper will provide an overview of the work that has been completed to date by the Communications Subproject in support of LOS C2 communications for UAS followed by an update of plans and progress for the BLOS phase of the project, with the focus on the UAS C2 spectrum aspects.

  18. Certification of Safety-Critical Software Under DO-178C and DO-278A

    NASA Technical Reports Server (NTRS)

    Jacklin, Stephen A.

    2012-01-01

    The RTCA has recently released DO-178C and DO-278A as new certification guidance for the production of airborne and ground-based air traffic management software, respectively. Additionally, RTCA special committee SC-205 has also produced, at the same time, five other companion documents. These documents are RTCA DO-248C, DO-330, DO-331, DO- 332, and DO-333. These supplements address frequently asked questions about software certification, provide guidance on tool qualification requirements, and illustrate the modifications recommended to DO-178C when using model-based software design, object oriented programming, and formal methods. The objective of this paper is to first explain the relationship of DO-178C to the former DO-178B in order to give those familiar with DO- 178B an indication of what has been changed and what has not been changed. With this background, the relationship of DO-178C and DO-278 to the new DO-278A document for ground-based software development is shown. Last, an overview of the new guidance contained in the tool qualification document and the three new supplements to DO-178C and DO-278A is presented. For those unfamiliar with DO-178B, this paper serves to provide an entry point to this new certification guidance for airborne and ground-based CNS/ATM software certification.

  19. 78 FR 33144 - Meeting: RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-03

    ... by SC-227. Final Draft, New Document, Operational and Functional Requirements and Safety Objectives... & Synthetic Vision Systems-- Discussion--Revised Terms of Reference. SC-214--Standards for Air Traffic Data...

  20. 78 FR 54509 - Tenth Meeting: RTCA Next Gen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-04

    ... Capabilities Work Group. Recommendation for Future Metroplex Optimization Activity. [cir] Recommendation for Future Use of Optimization of Airspace and Procedures in the Metroplex (OAPM) developed by the...

  1. 77 FR 3029 - Twentieth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... Aircraft Systems. The agenda will include the following: February 21, 2012 Welcome, Introductions, and... Breakout Sessions Systems Engineering Workgroup Command & Control Workgroup Sense & Avoid Workgroup Safety...

  2. Community Response to a Heavy Precipitation Event in High Temperature, Chemosynthetic Biofilms and Sediments

    NASA Astrophysics Data System (ADS)

    Meyer-Dombard, D. R.; Loiacono, S. T.; Shock, E.

    2012-12-01

    Coordinated analysis of the "Bison Pool" (BP) Environmental Genome and a complementary contextual geochemical dataset of ~75 parameters revealed biogeochemical cycling and metabolic and microbial community shifts in a Yellowstone National Park hot spring ecosystem (1). The >22m outflow of BP is a gradient of decreasing temperature, increasing dissolved oxygen, and changing availability of nutrients. Microbial life at BP transitions from a 92°C chemosynthetic community in the BP source pool to a 56°C photosynthetic mat community. Metagenomic data at BP showed the potential for both heterotrophic and autotrophic carbon metabolism (rTCA and acetyl-CoA cycles) in the highest temperature, chemosynthetic regions (1). This region of the outflow is dominated by Aquificales and Pyrococcus relatives, with smaller contributions of heterotrophic Bacteria. Following a 2h heavy precipitation event we observed an influx of exogenous organic material into the source pool supplied from the meadow surrounding the BP area. We sampled biomass and fluid at several locations within the outflow immediately following the event, and on several occasions for the next eight days. Elemental analysis and carbon and nitrogen isotopic analyses were conducted on biomass and sediment, and dissolved organic and inorganic carbon content and δ13C of fluids were analyzed. DNA and RNA were extracted, and following RT-PCR, nitrogen cycle functional gene expression was evaluated. Previous work at BP has shown that chemosynthetic biomass may carry isotopic signatures of fractionation during carbon fixation, via the acetyl-CoA and rTCA cycles (2). However, the addition of exogenous organic carbon during the rain event had an immediate and dramatic effect on the sediments and biofilms in the chemosynthetic zone of the outflow. Dissolved organic carbon was the highest measured in six years. Chemosynthetic biomass responded by incorporating the organic carbon. Carbon isotopic signatures in chemosynthetic biomass at "Bison Pool" have been previously measured at ~ -4‰ (2). However, immediately following the event, carbon in biomass was measured at ~ -25‰ (values similar to local soil and bison excrement). Biomass closest to the source of "Bison Pool" returned to ~ -4‰ within a few days, but biomass ~ 3m downstream was still ~ -14‰ eight days after the event. Carbon isotopic signatures of the dissolved inorganic carbon (DIC) were depleted relative to values measured in 2005-2009, possibly a result of a combination of added DIC in rain and heterotrophic waste produced using the exogenous depleted carbon; this depleted DIC persisted for the full study period. These results suggest that a shift from autotrophic to heterotrophic metabolism may occur following every significant precipitation event at BP, and support previous observations concerning potential periodic eutrophic conditions in this ecosystem (3). 1 Swingley, W.D. et al., PLoS ONE, 7(6): e38108. 2 Havig et al., 2011. JGR Biogeosciences, 116, G01005. 3 Loiacono, S.T. et al., 2012. EM, 14(5): 1272-1283.

  3. 76 FR 20436 - Ninth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ..., Administrative Remarks by Special Committee Leadership [ssbox] Designated Federal Officer (DFO): Mr. Brent... Results Update--ITT [ssbox] AeroMACS load estimations and performance evaluations--Max Ehammer (University...

  4. 78 FR 43962 - Meeting: Cancellation of RTCA Program Management Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-22

    .... Issued in Washington, DC, on July 12, 2013. Paige Williams, Management Analyst, NextGen, Business... Management Committee AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). [[Page 43963

  5. 77 FR 37732 - Fourteenth Meeting: RTCA Special Committee 223, Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ..., Introductions, and Administrative Remarks by Special Committee Leadership. Designated Federal Official (DFO): Mr..., DC, on June 15, 2012. Kathy Hitt, Program Analyst, Business Operations Branch, Federal Aviation...

  6. Mending the Gap, An Effort to Aid the Transfer of Formal Methods Technology

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly

    2009-01-01

    Formal methods can be applied to many of the development and verification activities required for civil avionics software. RTCA/DO-178B, Software Considerations in Airborne Systems and Equipment Certification, gives a brief description of using formal methods as an alternate method of compliance with the objectives of that standard. Despite this, the avionics industry at large has been hesitant to adopt formal methods, with few developers have actually used formal methods for certification credit. Why is this so, given the volume of evidence of the benefits of formal methods? This presentation will explore some of the challenges to using formal methods in a certification context and describe the effort by the Formal Methods Subgroup of RTCA SC-205/EUROCAE WG-71 to develop guidance to make the use of formal methods a recognized approach.

  7. Modulation of Induced Cytotoxicity of Doxorubicin by Using Apoferritin and Liposomal Cages

    PubMed Central

    Gumulec, Jaromir; Fojtu, Michaela; Raudenska, Martina; Sztalmachova, Marketa; Skotakova, Anna; Vlachova, Jana; Skalickova, Sylvie; Nejdl, Lukas; Kopel, Pavel; Knopfova, Lucia; Adam, Vojtech; Kizek, Rene; Stiborova, Marie; Babula, Petr; Masarik, Michal

    2014-01-01

    Doxorubicin is an effective chemotherapeutic drug, however, its toxicity is a significant limitation in therapy. Encapsulation of doxorubicin inside liposomes or ferritin cages decreases cardiotoxicity while maintaining anticancer potency. We synthesized novel apoferritin- and liposome-encapsulated forms of doxorubicin (“Apodox” and “lip-8-dox”) and compared its toxicity with doxorubicin and Myocet on prostate cell lines. Three different prostatic cell lines PNT1A, 22Rv1, and LNCaP were chosen. The toxicity of the modified doxorubicin forms was compared to conventional doxorubicin using the MTT assay, real-time cell impedance-based cell growth method (RTCA), and flow cytometry. The efficiency of doxorubicin entrapment was 56% in apoferritin cages and 42% in the liposome carrier. The accuracy of the RTCA system was verified by flow-cytometric analysis of cell viability. The doxorubicin half maximal inhibition concentrations (IC50) were determined as 170.5, 234.0, and 169.0 nM for PNT1A, 22Rv1, and LNCaP, respectively by RTCA. Lip8-dox is less toxic on the non-tumor cell line PNT1A compared to doxorubicin, while still maintaining the toxicity to tumorous cell lines similar to doxorubicin or epirubicin (IC50 = 2076.7 nM for PNT1A vs. 935.3 and 729.0 nM for 22Rv1 and LNCaP). Apodox IC50 was determined as follows: 603.1, 1344.2, and 931.2 nM for PNT1A, 22Rv1, and LNCaP. PMID:25514405

  8. 77 FR 50207 - Twenty-Second Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-20

    ... attend. More information on meeting location with maps, nearby hotels, and restaurants can be found at.... David Sicard, Manager, Business Operations Branch, Federal Aviation Administration. [FR Doc. 2012-20258...

  9. 78 FR 7476 - Fifth Meeting: RTCA Special Committee 227, Standards of Navigation Performance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-01

    ..., DC, on January 25, 2013. Cara Hunter, NAS Business Management Branch, ANG-A14, Federal Aviation... Breakout Session (to occur daily as appropriate) Other Business Next Meeting Discussion Adjourn Attendance...

  10. 78 FR 13395 - Meeting: RTCA Special Committee 223, Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ... Review: Convergence Sub-layer. Security. MAC Layer. Physical Layer. PICS. CRSL. Review/Approval of MOPS... Washington, DC, on February 21, 2013. Paige Williams, Management Analyst, NextGen, Business Operations Group...

  11. 77 FR 55895 - Meeting: RTCA Program Management Committee (PMC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... Enhanced Flight Vision System to Enable All-Weather Approach, Landing and Roll-Out to a Safe Taxi Speed... but limited to space availability. With the approval of the chairman, members of the public may...

  12. 77 FR 25781 - Twenty-First Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    .... The agenda will include the following: May 22, 2012 Opening Plenary Session Welcome/Introductions... Breakout Sessions Systems Engineering Workgroup C&C Workgroup S&A Workgroup Safety Workgroup Wednesday, May...

  13. 78 FR 51809 - Seventh Meeting: RTCA Special Committee 227, Standards of Navigation Performance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    .../Administrative Remarks Agenda Overview Review Committee Status and Revised TORs Datacom Situation and..., Federal Aviation Administration. [FR Doc. 2013-20420 Filed 8-20-13; 8:45 am] BILLING CODE 4910-13-P ...

  14. 78 FR 31627 - Thirteenth Meeting: RTCA Special Committee 222, Inmarsat AMS(R)S.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-24

    ... Conference. Participants who will be traveling to the meeting should contact Alan Schuster-Bruce, alan... open to the interested public but limited to space availability. With the approval of the chairman...

  15. Mass data graphics requirements for symbol generators: example 2D airport navagation and 3D terrain function

    NASA Astrophysics Data System (ADS)

    Schiefele, Jens; Bader, Joachim; Kastner, S.; Wiesemann, Thorsten; von Viebahn, Harro

    2002-07-01

    Next generation of cockpit display systems will display mass data. Mass data includes terrain, obstacle, and airport databases. Display formats will be two and eventually 3D. A prerequisite for the introduction of these new functions is the availability of certified graphics hardware. The paper describes functionality and required features of an aviation certified 2D/3D graphics board. This graphics board should be based on low-level and hi-level API calls. These graphic calls should be very similar to OpenGL. All software and the API must be aviation certified. As an example application, a 2D airport navigation function and a 3D terrain visualization is presented. The airport navigation format is based on highly precise airport database following EUROCAE ED-99/RTCA DO-272 specifications. Terrain resolution is based on EUROCAE ED-98/RTCA DO-276 requirements.

  16. Testing of CMA-2000 Microwave Landing System (MLS) airborne receiver

    NASA Astrophysics Data System (ADS)

    Labreche, L.; Murfin, A. J.

    1989-09-01

    Microwave landing system (MLS) is a precision approach and landing guidance system which provides position information and various air to ground data. Position information is provided on a wide coverage sector and is determined by an azimuth angle measurement, an elevation angle measurement, and a range measurement. MLS performance standards and testing of the MLS airborne receiver is mainly governed by Technical Standard Order TSO-C104 issued by the Federal Aviation Administration. This TSO defines detailed test procedures for use in determining the required performance under standard and stressed conditions. It also imposes disciplines on software development and testing procedures. Testing performed on the CMA-2000 MLS receiver and methods used in its validation are described. A computer automated test system has been developed to test for compliance with RTCA/DO-177 Minimum Operation Performance Standards. Extensive software verification and traceability tests designed to ensure compliance with RTCA/DO-178 are outlined.

  17. Curcumin and Viscum album Extract Decrease Proliferation and Cell Viability of Soft-Tissue Sarcoma Cells: An In Vitro Analysis of Eight Cell Lines Using Real-Time Monitoring and Colorimetric Assays.

    PubMed

    Harati, K; Behr, B; Daigeler, A; Hirsch, T; Jacobsen, F; Renner, M; Harati, A; Wallner, C; Lehnhardt, M; Becerikli, M

    2017-01-01

    The cytostatic effects of the polyphenol curcumin and Viscum album extract (VAE) were assessed in soft-tissue sarcoma (STS) cells. Eight human STS cell lines were used: fibrosarcoma (HT1080), liposarcoma (SW872, T778, MLS-402), synovial sarcoma (SW982, SYO1, 1273), and malignant fibrous histiocytoma (U2197). Primary human fibroblasts served as control cells. Cell proliferation, viability, and cell index (CI) were analyzed by BrdU assay, MTT assay, and real-time cell analysis (RTCA). As indicated by BrdU and MTT, curcumin significantly decreased the cell proliferation of five cell lines (HT1080, SW872, SYO1, 1273, and U2197) and the viability of two cell lines (SW872 and SW982). VAE led to significant decreases of proliferation in eight cell lines (HT1080, SW872, T778, MLS-402, SW982, SYO1, 1293, and U2197) and reduced viability in seven STS lines (HT1080, SW872, T778, MLS-402, SW982, SYO1, and 1273). As indicated by RTCA for 160 h, curcumin decreased the CI of all synovial sarcoma cell lines as well as T778 and HT1080. VAE diminished the CI in most of the synovial sarcoma (SW982, SYO1) and liposarcoma (SW872, T778) cell lines as well as HT1080. Primary fibroblasts were not affected adversely by the two compounds in RTCA. Curcumin and VAE can inhibit the proliferation and viability of STS cells.

  18. 75 FR 30899 - Fourth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... Phillips Co-Chair: Mr. Aloke Roy, Honeywell International Co-Chair: Mr. Ward Hall, ITT Corporation Agenda... Status 3rd Plenary action item status Assignment of MOPS working group leader AeroMACS test and...

  19. 75 FR 54001 - Fifty-Second Meeting: RTCA Special Committee 186: Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... unless stated otherwise. ADDRESSES: The meeting will be held at the Dutch National Aerospace Laboratory... Items/Work Programs. Adjourn Plenary. Attendance is open to the interested public but limited to space...

  20. 77 FR 64837 - Federal Aviation Administration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-23

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Fourth Meeting: RTCA Special Committee 227, Standards of Navigation Performance AGENCY: Federal Aviation Administration (FAA), U.S... Operations Group, Federal Aviation Administration. [FR Doc. 2012-26034 Filed 10-22-12; 8:45 am] BILLING CODE...

  1. 78 FR 41183 - Federal Aviation Administration

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... DEPARTMENT OF TRANSPORTATION Federal Aviation Administration Meeting: RTCA Program Management Committee AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION... Operations Group, Federal Aviation Administration. [FR Doc. 2013-16464 Filed 7-8-13; 8:45 am] BILLING CODE...

  2. 75 FR 61818 - Eighty-Third Meeting: RTCA Special Committee 159: Global Positioning System (GPS).

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-06

    ... & Hilton-ATA Room. All Day, Working Group 7, GPS/Antennas, ARINC Room. Friday, October 29 Plenary Session...) GPS/Antennas (WG-7) Review of EUROCAE Activities. Nav and ADS-B Out Equipment Requirements--Discussion...

  3. GPS/GNSS Antenna Characterization : GPS-ABC Workshop V RTCA Washington, DC October 14, 2016.

    DOT National Transportation Integrated Search

    2016-10-14

    One component of the Department of Transportations GPS Adjacent Band : Compatibility Study is the characterization of GPS/GNSS receiver antennas : Such characterization is needed to: : Compare radiated and conducted (wired) test result...

  4. 76 FR 38740 - Tenth Meeting: RTCA Special Committee 223: Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... Chapters 5,6,8--EUROCAE Chap 5--Service Specific CS Draft Chap 8--Physical Layer Discussion of Security Sub-layer--Honeywell MOPS Outline Wednesday, August 10, 2011 Wednesday Morning--MOPS WG Breakout Session...

  5. 77 FR 58209 - Fourth Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... discussion on TSO-C99A (Oxygen Mask Communication) Continue discussion on the following: Risks of usage of... manufacturers Addition of noise test requirement to the vibration test variable nature of Oxygen Mask Microphone...

  6. Technical Note: System for evaluating local hypothermia as a radioprotector of the rectum in a small animal model.

    PubMed

    Hrycushko, Brian A; Bing, Chenchen; Futch, Cecil; Wodzak, Michelle; Stojadinovic, Strahinja; Medin, Paul M; Chopra, Rajiv

    2017-08-01

    The protective effects of induced or even accidental hypothermia on the human body are widespread with several medical uses currently under active research. In vitro experiments using human cell lines have shown hypothermia provides a radioprotective effect that becomes more pronounced at large, single-fraction doses common to stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS) treatments. This work describes the development of a system to evaluate local hypothermia for a radioprotective effect of the rat rectum during a large dose of radiation relevant to prostate SBRT. This includes the evaluation of a 3D-printed small animal rectal cooling device and the integration with a small animal irradiator. A 3-cm long, dual-lumen rectal temperature control apparatus (RTCA) was designed in SOLIDWORKS CAD for 3D printing. The RTCA was capable of recirculating flow in a device small enough for insertion into the rat rectum, with a metal support rod for strength as well as visibility during radiation treatment planning. The outer walls of the RTCA comprised of thin heat shrink plastic, achieving efficient heat transfer into adjacent tissues. Following leak-proof testing, fiber optic temperature probes were used to evaluate the temperature over time when placed adjacent to the cooling device within the rat rectum. MRI thermometry characterized the relative temperature distribution in concentric ROIs surrounding the probe. Integration with an image-guided small animal irradiator and associated treatment planning system included evaluation for imaging artifacts and effect of brass tubing on dose calculation. The rectal temperature adjacent to the cooling device decreased from body temperature to 15°C within 10-20 min from device insertion and was maintained at 15 ± 3°C during active cooling for the evaluated time of one hour. MR thermometry revealed a steep temperature gradient with increasing distance from the cooling device with the desired temperature range maintained within the surrounding few millimeters. A 3D-printed rectal cooling device was fabricated for the purpose of inducing local hypothermia in the rat rectum. The RTCA was simply integrated with an image-guided small animal irradiator and Monte Carlo-based treatment planning system to facilitate an in vivo investigation of the radioprotective effect of hypothermia for late rectal toxicity following a single large dose of radiation. © 2017 American Association of Physicists in Medicine.

  7. Formal Methods Case Studies for DO-333

    NASA Technical Reports Server (NTRS)

    Cofer, Darren; Miller, Steven P.

    2014-01-01

    RTCA DO-333, Formal Methods Supplement to DO-178C and DO-278A provides guidance for software developers wishing to use formal methods in the certification of airborne systems and air traffic management systems. The supplement identifies the modifications and additions to DO-178C and DO-278A objectives, activities, and software life cycle data that should be addressed when formal methods are used as part of the software development process. This report presents three case studies describing the use of different classes of formal methods to satisfy certification objectives for a common avionics example - a dual-channel Flight Guidance System. The three case studies illustrate the use of theorem proving, model checking, and abstract interpretation. The material presented is not intended to represent a complete certification effort. Rather, the purpose is to illustrate how formal methods can be used in a realistic avionics software development project, with a focus on the evidence produced that could be used to satisfy the verification objectives found in Section 6 of DO-178C.

  8. 75 FR 65706 - Fifteenth Plenary Meeting, RTCA Special Committee 205/EUROCAE WG 71: Software Considerations in...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-26

    ..., Software Considerations in Airborne Systems and Equipment Certification ED-94B/DO-248B, Final Annual Report for Clarification of ED-94B/DO-178B ``Software Considerations In Airborne Systems And Equipment...

  9. 75 FR 7305 - RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC) Revised Agenda...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-18

    ... cancelled due to inclement weather. This meeting is being scheduled with less than 15 days calendar notice... limited to space availability. With the approval of the chairmen, members of the public may present oral...

  10. GNSS receiver use-case development GPS-ABC workshop VI RTCA Washington, DC March 30, 2017.

    DOT National Transportation Integrated Search

    2017-03-30

    The purpose of this workshop was to discuss the results from testing of various categories of GPS/Global Navigation Satellite System (GNSS) receivers to include aviation (non-certified), cellular, general location/navigation, high precision and netwo...

  11. 75 FR 38863 - Tenth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY...-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing...: Enhanced Flight [[Page 38864

  12. 76 FR 72996 - Eleventh Meeting: RTCA Special Committee 223 Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ... SESAR P15.2.7 Profiles Definition for AeroMACS Chap 8--Physical Layer--Updates per WiMAX Forum Chap 5... Security Sub-layer--Honeywell Review draft of Environmental (DO-160G)--Rockwell Collins Review draft PICS...

  13. 77 FR 48584 - Tenth Meeting: RTCA Special Committee 222, Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-14

    ... accommodate editing activities on both the MASPS and MOPs. Webex/telecom will be available on both days... the MASPS and MOPs. Webex/telecom will be available on both days. Attendance is open to the interested...

  14. 77 FR 49851 - Nineteenth Meeting: RTCA Special Committee 216, Aeronautical Systems Security (Joint Meeting With...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... Welcome Introduction, Logistics Eurocae Context Presentation Joint Plenary: Scope and purpose of this meeting with focus on ED-202A/ DO-326A and ED-204 Open Consultation/FRAC requirements & expectations Coordination between drafting [[Page 49852

  15. Food-Web Complexity in Guaymas Basin Hydrothermal Vents and Cold Seeps.

    PubMed

    Portail, Marie; Olu, Karine; Dubois, Stanislas F; Escobar-Briones, Elva; Gelinas, Yves; Menot, Lénaick; Sarrazin, Jozée

    In the Guaymas Basin, the presence of cold seeps and hydrothermal vents in close proximity, similar sedimentary settings and comparable depths offers a unique opportunity to assess and compare the functioning of these deep-sea chemosynthetic ecosystems. The food webs of five seep and four vent assemblages were studied using stable carbon and nitrogen isotope analyses. Although the two ecosystems shared similar potential basal sources, their food webs differed: seeps relied predominantly on methanotrophy and thiotrophy via the Calvin-Benson-Bassham (CBB) cycle and vents on petroleum-derived organic matter and thiotrophy via the CBB and reductive tricarboxylic acid (rTCA) cycles. In contrast to symbiotic species, the heterotrophic fauna exhibited high trophic flexibility among assemblages, suggesting weak trophic links to the metabolic diversity of chemosynthetic primary producers. At both ecosystems, food webs did not appear to be organised through predator-prey links but rather through weak trophic relationships among co-occurring species. Examples of trophic or spatial niche differentiation highlighted the importance of species-sorting processes within chemosynthetic ecosystems. Variability in food web structure, addressed through Bayesian metrics, revealed consistent trends across ecosystems. Food-web complexity significantly decreased with increasing methane concentrations, a common proxy for the intensity of seep and vent fluid fluxes. Although high fluid-fluxes have the potential to enhance primary productivity, they generate environmental constraints that may limit microbial diversity, colonisation of consumers and the structuring role of competitive interactions, leading to an overall reduction of food-web complexity and an increase in trophic redundancy. Heterogeneity provided by foundation species was identified as an additional structuring factor. According to their biological activities, foundation species may have the potential to partly release the competitive pressure within communities of low fluid-flux habitats. Finally, ecosystem functioning in vents and seeps was highly similar despite environmental differences (e.g. physico-chemistry, dominant basal sources) suggesting that ecological niches are not specifically linked to the nature of fluids. This comparison of seep and vent functioning in the Guaymas basin thus provides further supports to the hypothesis of continuity among deep-sea chemosynthetic ecosystems.

  16. Food-Web Complexity in Guaymas Basin Hydrothermal Vents and Cold Seeps

    PubMed Central

    Olu, Karine; Dubois, Stanislas F.; Escobar-Briones, Elva; Gelinas, Yves; Menot, Lénaick; Sarrazin, Jozée

    2016-01-01

    In the Guaymas Basin, the presence of cold seeps and hydrothermal vents in close proximity, similar sedimentary settings and comparable depths offers a unique opportunity to assess and compare the functioning of these deep-sea chemosynthetic ecosystems. The food webs of five seep and four vent assemblages were studied using stable carbon and nitrogen isotope analyses. Although the two ecosystems shared similar potential basal sources, their food webs differed: seeps relied predominantly on methanotrophy and thiotrophy via the Calvin-Benson-Bassham (CBB) cycle and vents on petroleum-derived organic matter and thiotrophy via the CBB and reductive tricarboxylic acid (rTCA) cycles. In contrast to symbiotic species, the heterotrophic fauna exhibited high trophic flexibility among assemblages, suggesting weak trophic links to the metabolic diversity of chemosynthetic primary producers. At both ecosystems, food webs did not appear to be organised through predator-prey links but rather through weak trophic relationships among co-occurring species. Examples of trophic or spatial niche differentiation highlighted the importance of species-sorting processes within chemosynthetic ecosystems. Variability in food web structure, addressed through Bayesian metrics, revealed consistent trends across ecosystems. Food-web complexity significantly decreased with increasing methane concentrations, a common proxy for the intensity of seep and vent fluid fluxes. Although high fluid-fluxes have the potential to enhance primary productivity, they generate environmental constraints that may limit microbial diversity, colonisation of consumers and the structuring role of competitive interactions, leading to an overall reduction of food-web complexity and an increase in trophic redundancy. Heterogeneity provided by foundation species was identified as an additional structuring factor. According to their biological activities, foundation species may have the potential to partly release the competitive pressure within communities of low fluid-flux habitats. Finally, ecosystem functioning in vents and seeps was highly similar despite environmental differences (e.g. physico-chemistry, dominant basal sources) suggesting that ecological niches are not specifically linked to the nature of fluids. This comparison of seep and vent functioning in the Guaymas basin thus provides further supports to the hypothesis of continuity among deep-sea chemosynthetic ecosystems. PMID:27683216

  17. 77 FR 3030 - Twenty-Eighth Meeting: RTCA Special Committee 206: Aeronautical Information and Meteorological...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... and normal definitions Review proposed TOR changes ConUse Review February 7, 2012 ConUse Review... proposed TOR changes and new or modified Sub-groups' roles and responsibilities Decision to release ConUse...] BILLING CODE 4910-13-P ...

  18. GPS-ABC Radiated Chamber Testing Overview and Results : GPS-ABC Workshop V RTCA Washington, DC October 14, 2016.

    DOT National Transportation Integrated Search

    2016-10-14

    GPS receiver testing was carried out April 2529, 2016 at the Army : Research Laboratory's (ARL) Electromagnetic Vulnerability Assessment : Facility (EMVAF), White Sands Missile Range (WSMR), NM : EMVAF 100 x 70 x 40 Anechoic C...

  19. Recap and Program Plan Update [GPS Adjacent Band Compatibility Assessment Workshop IV RTCA - Washington, DC

    DOT National Transportation Integrated Search

    2015-10-02

    Initial WorkshopI held on September 18, 2014 at the Volpe Center; Overview of DOT GPS Adjacent Band Compatibility Assessment Plan and plans/timeline for implementation; Presentation on GPS use cases and list of representative GPS receivers; Descri...

  20. Inverse modeling/transmit power levels : GPS-ABC Workshop VI RTCA, Washington, DC, March 30, 2017.

    DOT National Transportation Integrated Search

    2017-03-30

    This presentation provides models for adjacent band transmitters (base stations and handsets), and : GNSS receiver antenna patterns, as well as provides C/A results for: (1) impacted regions for adjacent band transmitters of : various types, (2) maxi...

  1. An investigation of microwave landing guidance system signal requirements for conventionally equipped civilian aircraft.

    DOT National Transportation Integrated Search

    1971-06-01

    The report describes efforts leading to the determination of minimum suitable scan rates for the azimuth and Elevation functions of the microwave Landing Guidance System (LGS) proposed by RTCA SC-117, based on performance requirements of two conventi...

  2. 75 FR 27618 - RTCA Government/Industry Air Traffic Management Advisory Committee (ATMAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ... Plenary (Welcome and Introductions); Trajectory Operations (TOps) Work Group Presentation of Document... Work Group (NGIWG) Report, Discussion, and possible Next Steps; ADS-B Work Group Presentation of Legacy... Activity Airspace Program (NSAAP) Presentation Requested by Requirements and Planning Work Group, Airspace...

  3. 75 FR 63534 - Seventh Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... 222: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route... Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The meeting will be held...

  4. 75 FR 15770 - Fifth Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ...: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services... Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The meeting will be held...

  5. 75 FR 39724 - Sixth Meeting-Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ...: Inmarsat Aeronautical Mobile Satellite (Route) Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services... Committee 222: Inmarsat Aeronautical Mobile Satellite (Route) Services. DATES: The meeting will be held...

  6. 77 FR 16890 - Second Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ... Proposed committee letter to invite additional headsets, MIC's and CVR manufacturers Addition of noise test... FAA info letter addressing use of Active Noise Reduction (ANR) and Powered ANR headsets to discuss... Business Establish Agenda for Next Meeting [[Page 16891

  7. Considerations for RTCA Phase 2 Low Size, Weight, and Power (SWAP) Surveillance Requirements. UAS Integration in the NAS

    NASA Technical Reports Server (NTRS)

    Santiago, Confesor

    2017-01-01

    RTCA (Radio Technical Commission for Aeronautics) Special Committee 228 has initiated a second phase for the development of minimum operational performance standards (MOPS) for UAS (Unmanned Aircraft Systems) detect and avoid (DAA) systems. Technologies to enable UAS with less available Size, Weight, and Power (SWaP) will be considered. A white paper is in development for what topics and issues need to be addressed to develop DAA requirements for low SWAP surveillance systems. This briefing will document the issues to be investigated in SC-228. It will also serve as a review with the committee to get feedback so the white paper can be written and finalized. These topics and issues are not necessarily all the things that NASA will contribute to SC-228 during Phase 2, but what the overall committee needs to accomplish. A portion of the work will be in NASA's UAS in the NAS (National Airspace System) project plan.

  8. Accuracy Assessment of the Precise Point Positioning for Different Troposphere Models

    NASA Astrophysics Data System (ADS)

    Oguz Selbesoglu, Mahmut; Gurturk, Mert; Soycan, Metin

    2016-04-01

    This study investigates the accuracy and repeatability of PPP technique at different latitudes by using different troposphere delay models. Nine IGS stations were selected between 00-800 latitudes at northern hemisphere and southern hemisphere. Coordinates were obtained for 7 days at 1 hour intervals in summer and winter. At first, the coordinates were estimated by using Niell troposphere delay model with and without including north and east gradients in order to investigate the contribution of troposphere delay gradients to the positioning . Secondly, Saastamoinen model was used to eliminate troposphere path delays by using standart atmosphere parameters were extrapolated for all station levels. Finally, coordinates were estimated by using RTCA-MOPS empirical troposphere delay model. Results demonstrate that Niell troposphere delay model with horizontal gradients has better mean values of rms errors 0.09 % and 65 % than the Niell troposphere model without horizontal gradients and RTCA-MOPS model, respectively. Saastamoinen model mean values of rms errors were obtained approximately 4 times bigger than the Niell troposphere delay model with horizontal gradients.

  9. 78 FR 63279 - Third Meeting: RTCA Tactical Operations Committee (TOC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... Operations Committee (TOC) AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation... hereby given for a meeting of the Tactical Operations Committee (TOC). The agenda will include the following: November 19, 2013 Opening of Meeting/Introduction of TOC Members Official Statement of Designated...

  10. GPS-ABC Workshop Wired (Conducted) Test Results : GPS‐ABC Workshop V RTCA Washington, DC October 14, 2016.

    DOT National Transportation Integrated Search

    2016-10-14

    Overview: -Tests executed week of 25 July with 14 GNSS receivers ; -Representative set of equipment from chamber testing from each receiver category (except space) ; -Receivers tested were USG provided ; -Same test instrumentation for wired as with r...

  11. 78 FR 20168 - Twenty Fourth Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... Washington, DC, on March 28, 2013. Paige Williams, Management Analyst, NextGen, Business Operations Group... Introductions Review Meeting Agenda Review/Approval of Twenty Third Plenary Meeting Summary Leadership Update... for Unmanned Aircraft Systems and Minimum Aviation System Performance Standards Other Business Adjourn...

  12. 77 FR 2342 - Fifth Meeting: RTCA, Next Gen Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... University, Florida NextGen Test Bed, 557 Innovation Way, Daytona Beach, FL 32114. FOR FURTHER INFORMATION... Capabilities to Identified Metroplexes--a recommendation derived from a mapping of integrated capabilities to... specific capabilities. Lunch Break Review and Approve Recommendations for Submission to FAA DataComm...

  13. 76 FR 50811 - Seventeenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-16

    .... Agenda Tuesday, September 6th (Pre-Meeting Events) 9 a.m. to 12 p.m. Optional--DHS National Cybersecurity... cooperation. 11:15 a.m.-12 p.m., DHS Briefing on the Cybersecurity Control System Security (CSSP) Program. 1 p...

  14. 78 FR 5242 - 32nd Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-24

    ... 206, Aeronautical Information and Meteorological Data Link Services AGENCY: Federal Aviation... 206, Aeronautical Information and Meteorological Data Link Services. SUMMARY: The FAA is issuing this... Information and Meteorological Data Link Services. DATES: The meeting will be held February 11-15, 2013 from 8...

  15. 77 FR 56253 - 60th Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation... 135, Environmental Conditions and Test Procedures for Airborne Equipment SUMMARY: The FAA is issuing..., Environmental Conditions and Test Procedures for Airborne Equipment DATES: The meeting will be held November 8...

  16. 77 FR 15449 - 59th Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation... 135, Environmental Conditions and Test Procedures for Airborne Equipment. SUMMARY: The FAA is issuing..., Environmental Conditions and Test Procedures for Airborne Equipment. DATES: The meeting will be held April 19...

  17. 78 FR 43963 - Sixty-Second Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-22

    ... Committee 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation... 135, Environmental Conditions and Test Procedures for Airborne Equipment. SUMMARY: The FAA is issuing..., Environmental Conditions and Test Procedures for Airborne Equipment. DATES: The meeting will be held November 13...

  18. 78 FR 7850 - Sixty First Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... Committee 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation... 135, Environmental Conditions and Test Procedures for Airborne Equipment. SUMMARY: The FAA is issuing..., Environmental Conditions and Test Procedures for Airborne Equipment. DATES: The meeting will be held March 21...

  19. Ultra-wideband technology radio frequency interference effects to GPS and interference scenario development : first interim report

    DOT National Transportation Integrated Search

    2000-09-12

    In October, 1999, at the request of the Department of Transportation (DoT), the RTCA undertook an effort to investigate the radio frequency interference (RFI) environment in the vicinity of the new Global Positioning System (GPS) L5 frequency (1176.4...

  20. 75 FR 52591 - Seventh Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Committee 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures AGENCY: Federal... Secondary Barriers and Alternative Flight Deck Security Procedures. SUMMARY: The FAA is issuing this notice... Alternative Flight Deck Security Procedures. DATES: The meeting will be held September 14-15, 2010. September...

  1. UAS Integration in the NAS Project: Part Task 6 V & V Simulation: Primary Results

    NASA Technical Reports Server (NTRS)

    Rorie, Conrad; Fern, Lisa; Shively, Jay; Santiago, Confesor

    2016-01-01

    This is a presentation of the preliminary results on final V and V (Verification and Validation) activity of [RTCA (Radio Technical Commission for Aeronautics)] SC (Special Committee)-228 DAA (Detect and Avoid) HMI (Human-Machine Interface) requirements for display alerting and guidance.

  2. 78 FR 61445 - Seventy-Sixth Meeting: RTCA Special Committee 147, Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-03

    ... Committee 147, Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Traffic Alert and Collision Avoidance Systems Airborne Equipment. SUMMARY: The FAA is issuing this notice... Performance Standards for Traffic Alert and Collision Avoidance Systems Airborne Equipment. DATES: The meeting...

  3. 78 FR 66419 - Seventy Sixth Meeting: RTCA Special Committee 147, Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... Committee 147, Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Traffic Alert and Collision Avoidance Systems Airborne Equipment. SUMMARY: The FAA is issuing this notice... Performance Standards for Traffic Alert and Collision Avoidance Systems Airborne Equipment. DATES: The meeting...

  4. 78 FR 28940 - Ninth Meeting: RTCA Next Gen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-16

    .... Huerta FAA NextGen Performance SnapShots Featured PBN Implementation Location Data Sources for Measuring... by the Business Case and Performance Metrics Work Group Recommendation for Implementing Categorical Exclusion Contained in FAA Modernization Act of 2012 Recommendation developed by CatEx2 Task Group for...

  5. CrossTalk. The Journal of Defense Software Engineering. Volume 25, Number 1, Jan/Feb 2012

    DTIC Science & Technology

    2012-01-01

    Considerations in Airborne Systems and Equipment Certification – RTCA/DO-178B,” Washington, D.C., 1992. 5. Ishikawa , Kaoru (Translator: J. H...significant, repeated issue, a formal root cause analysis process is performed. This method uses fishbone or Ishikawa diagrams [5], where possible

  6. 78 FR 5860 - Eighth Meeting: RTCA Next Gen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-28

    ...] Preliminary report to identify and mitigate barriers to implementing PBN. Issues associated with Implementing RNAV/RNP [cir] An open discussion by the Committee of Non-technical barriers of PBN procedures... NextGen. Cat Ex 2 Task Group [cir] Preliminary report on the recommendation for implementing new...

  7. 76 FR 11846 - 24th Meeting: RTCA Special Committee 206: EUROCAE WG 76 Plenary: AIS and MET Data Link Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ... 21-25, 2011 from 9 a.m. to 5 p.m. ADDRESSES: The meeting will be held at Honeywell Aerospace, Phoenix.... Attendance is open to the interested public but limited to space availability. With the approval of the...

  8. FAA aircraft certification human factors and operations checklist for standalone GPS receivers (TSO C-129 class A)

    DOT National Transportation Integrated Search

    1995-04-01

    This checklist is designed to assist FAA certification personnel and GPS : receiver manufacturers in the evaluation of the pilot-system interface : characteristics of GPS receivers to be certified according to TSO C129 A1, : RTCA/DO-208, and AC 20-13...

  9. 77 FR 39321 - Eighth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Sizes AGENCY: Federal... Special Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Sizes. SUMMARY... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Sizes. DATES: The meeting will...

  10. 78 FR 6845 - Eleventh Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-31

    ... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal... Special Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. DATES: The meeting...

  11. 78 FR 16031 - Twelfth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-13

    ... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal... Special Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. DATES: The meeting...

  12. 77 FR 71028 - Twelfth Meeting: RTCA Special Committee 223, Airport Surface Wireless Communications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-28

    ... by Special Committee Leadership Agenda Overview Review/Approve prior Plenary Meeting Summary and... committee at any time. Issued in Washington, DC, on November 8, 2012. Richard F. Gonzalez, Management Analyst, Business Operations Group, Federal Aviation Administration. [FR Doc. 2012-28854 Filed 11-27-12; 8...

  13. 77 FR 29749 - 74th Meeting: RTCA Special Committee 147, Minimal Operations Performance Standards for Traffic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... 147, Minimal Operations Performance Standards for Traffic Alert and Collision Avoidance Systems... Traffic Alert and Collision Avoidance Systems Airborne Equipment. SUMMARY: The FAA is issuing this notice... Performance Standards for Traffic Alert and Collision Avoidance Systems Airborne Equipment. DATES: The meeting...

  14. 78 FR 6401 - Seventy Fifth Meeting: RTCA Special Committee 147, Minimum Operational Performance Standards for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ... Committee 147, Minimum Operational Performance Standards for Traffic Alert and Collision Avoidance Systems... Traffic Alert and Collision Avoidance Systems Airborne Equipment. SUMMARY: The FAA is issuing this notice... Performance Standards for Traffic Alert and Collision Avoidance Systems Airborne Equipment. DATES: The meeting...

  15. 77 FR 30584 - Thirtieth Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... preliminary roadmap SG1 report SG2 report SG3 report SAE G-10 AI ARP Briefing to SC-206 Plenary 12:30 p.m... document for release to the PMC SG3 report PMC decision on TOR revision Action item review Future meeting...

  16. 78 FR 12136 - Fifty Eighth Meeting: RTCA Special Committee 186, Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-21

    .... Issued in Washington, DC, on February 19, 2013. Paige Williams, Management Analyst, Business Operations... Trajectory Management Other? Other Business. None Identified Review Action Items/Work Programs. Adjourn...) [ssquf] Flight-deck Interval Management (FIM) [ssquf] CAVS and CDTI Assisted Pilot Procedures (CAPP...

  17. Framework for Mapping of Receiver Interference Tolerance Masks to Tolerable Effective Isotropic Radiated Power Levels : GPS ABC Workshop V RTCA Washington, DC October 14, 2016.

    DOT National Transportation Integrated Search

    2016-10-14

    Outline : : Interference Tolerance Mask (ITM) to Effective Isotropic Radiated Power (IRP) for the particular case of a single transmitter : : ITM() to IRP() for the general case of multiple transmitters : : Input parameters needed to solv...

  18. GPS-ABC radiated chamber testing overview and results : GPS-ABC Workshop VI : RTCA Washington, DC, March 30, 2017.

    DOT National Transportation Integrated Search

    2017-03-30

    This presentation, which was given during the GPS-ABC Workshop VI in Washington, DC on March 30, 2017 details the authors' radiated testing protocols and results. GPS receiver testing was carried out April 25-29, 2016 at the Army : Research Laborator...

  19. 77 FR 22835 - Second Meeting: RTCA Special Committee 227, Standards of Navigation Performance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Agenda Overview Review of SC-227 Workspace Changes/Process, and MASPS/MOPS Workgroup Leadership Review... Applicable to MOPS Other Business Establish Agenda for Next Meeting. Attendance is open to the interested.... John Raper, Manager, Business Operations Branch, Federal Aviation Administration. [FR Doc. 2012-9193...

  20. 76 FR 34123 - 25th Meeting: RTCA Special Committee 206: Aeronautical Information and Meteorological Data Link

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... WG3 Meetings 28 June--Tuesday 9 a.m. Joint Plenary meeting with AEEC Systems Architecture & Interface... Meeting Plans and Dates Other Business 1 July--Friday 9 a.m. WG1, WG2, and WG3 Meetings 12 p.m. Adjourn...

  1. 77 FR 8325 - Sixth Meeting: RTCA Special Committee 225, Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... 225, Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size AGENCY: Federal... Committee 225, Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size. SUMMARY: The FAA..., Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size. DATES: The meeting will be held...

  2. 78 FR 55773 - Fourteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-11

    ... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal... Special Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size DATES: The meeting...

  3. 78 FR 38093 - Thirteenth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-25

    ... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal... Special Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY... Committee 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. DATES: The meeting...

  4. 76 FR 79754 - Twelfth Meeting: RTCA Special Committee 220, Automatic Flight Guidance and Control

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-22

    ... technologies Administrative items (meeting schedule, location, and next meeting agenda) Any other business... 2 status--progress, issues and plan Review of WG 3 status--progress, issues and plans Review action.... Issued in Washington, DC, on December 15, 2011. Robert L. Bostiga, Manager, Business Operations Branch...

  5. USGS earthquake hazards program (EHP) GPS use case : earthquake early warning (EEW) and shake alert

    DOT National Transportation Integrated Search

    2017-03-30

    GPS Adjacent Band Workshop VI RTCA Inc., Washington D.C., 30 March 2017. USGS GPS receiver use case - Real-Time GPS for EEW -Continued: CRITICAL EFFECT - The GNSS component of the Shake Alert system augments the inertial sensors and is especial...

  6. 77 FR 37733 - Third Meeting: RTCA Special Committee 226, Audio Systems and Equipment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... adaptive technology during test. Discuss results of proposed committee letter(s) to invite additional... to remove CVR Area Microphone requirements from standard in lieu of ED-112. FAA info letter... noise test requirement to combine with the vibration test. Other Business. Establish agenda for next...

  7. 78 FR 19355 - Announcement of Charter Renewal of the Radio Technical Commission for Aeronautics (RTCA), Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... resolution of issues and challenges involving air transportation concepts, requirements, operational... impact the future Air Traffic Management System. This charter renewal will take effect on April 1, 2013... operational and technological issues that impact the Next Generation Air Transportation System (NextGen...

  8. The Krebs Uric Acid Cycle: A Forgotten Krebs Cycle.

    PubMed

    Salway, Jack G

    2018-05-25

    Hans Kornberg wrote a paper entitled 'Krebs and his trinity of cycles' commenting that every school biology student knows of the Krebs cycle, but few know that Krebs discovered two other cycles. These are (i) the ornithine cycle (urea cycle), (ii) the citric acid cycle (tricarboxylic acid or TCA cycle), and (iii) the glyoxylate cycle that was described by Krebs and Kornberg. Ironically, Kornberg, codiscoverer of the 'glyoxylate cycle', overlooked a fourth Krebs cycle - (iv) the uric acid cycle. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. 75 FR 47881 - Fifty-Sixth Meeting, RTCA Special Committee 135: Environmental Conditions and Test Procedures for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ... Committee 135: Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation...: Environmental Conditions and Test Procedures for Airborne Equipment meeting. SUMMARY: The FAA is issuing this... Procedures for Airborne Equipment. DATES: The meeting will be held October 5-7, 2010, starting at 9 a.m...

  10. 78 FR 6400 - Twenty Third Meeting: RTCA Special Committee 203, Unmanned Aircraft Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-30

    ..., Washington, DC 20036, or by telephone at (202) 833- 9339, fax at (202) 833-9434, or Web site at http://www...-Morning/Afternoon Workgroup Breakout Sessions System Engineering Workgroup Human Factors Subgroup C&C... Breakout Sessions System Engineering Workgroup C&C Workgroup S&A Workgroup Safety Workgroup Friday...

  11. 75 FR 9016 - Fifth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures AGENCY: Federal... Secondary Barriers and Alternative Flight Deck Security Procedures. SUMMARY: The FAA is issuing this notice... Alternative Flight Deck Security Procedures. DATES: The meeting will be held March 16-17, 2010. March 16th...

  12. 76 FR 38741 - Tenth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures AGENCY: Federal... Secondary Barriers and Alternative Flight Deck Security Procedures. SUMMARY: The FAA is issuing this notice... Alternative Flight Deck Security Procedures. DATES: The meeting will be held July 19-20, from 9:00 a.m. to 5...

  13. 78 FR 16756 - Twenty-Second Meeting: RTCA Special Committee 213, Enhanced Flight Vision Systems/Synthetic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-18

    ... Committee 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation... 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing..., Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held April...

  14. 76 FR 22163 - Ninth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures AGENCY: Federal... Secondary Barriers and Alternative Flight Deck Security Procedures. SUMMARY: The FAA is issuing this notice... Alternative Flight Deck Security Procedures. DATES: The meeting will be held May 10-11, 2011, from 9 a.m. to 5...

  15. 77 FR 16890 - Eighteenth Meeting: RTCA Special Committee 213, Enhanced Flight Visions Systems/Synthetic Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ... Committee 213, Enhanced Flight Visions Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation... 213, Enhanced Flight Visions Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing... Flight Visions Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held April 17-19...

  16. CrossTalk: The Journal of Defense Software Engineering. Volume 25, Number 1, January/February 2012

    DTIC Science & Technology

    2012-02-01

    Equipment Certification – RTCA/DO-178B,” Washington, D.C., 1992. 5. Ishikawa , Kaoru (Translator: J. H. Loftus), Introduction to Quality Control, Tokyo...cause analysis process is performed. This method uses fishbone or Ishikawa diagrams [5], where possible causes for the outliers are listed, followed by

  17. Human Factors and Operations Issues in GPS and WAAS Sensor Approvals A Review and Comparison of FAA and RTCA Documents

    DOT National Transportation Integrated Search

    1997-07-01

    This report is the culmination of the first task in a project to evaluate human factors and operations issues associated : with the integration of Class C Global Positioning System (GPS) sensors and Class Beta GPS/Wide Area Augmentation System : (WAA...

  18. 78 FR 5557 - Twenty-First Meeting: RTCA Special Committee 213, Enhanced Flight Vision Systems/Synthetic Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-25

    ... Committee 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation... 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing..., Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held...

  19. 78 FR 55774 - Twenty Fourth Meeting: RTCA Special Committee 213, Enhanced Flight Vision Systems/Synthetic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-11

    ... Committee 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation... 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing..., Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held October...

  20. 75 FR 17202 - Eighth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY...-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing...: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held April...

  1. 77 FR 56254 - Twentieth Meeting: RTCA Special Committee 213, Enhanced Flight Vision Systems/Synthetic Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... Committee 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY: Federal Aviation... 213, Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY: The FAA is issuing... Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will be held October 2-4...

  2. 78 FR 69929 - Fifty-Ninth Meeting: RTCA Special Committee 186, Automatic Dependent Surveillance-Broadcast (ADS-B)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-21

    .... December 13 Chairman's Introductory Remarks Working Group Reports Review of Meeting Agenda Review/Approval... Services (SBS) Program--Status. EUROCAE WG-51 Report Review/Approval--New Document--Safety, Performance and.../SC186-326. Review/Approval--Revised DO-317A--Minimum Operational Performance Standards (MOPS) for...

  3. 77 FR 56253 - Ninth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems-Small...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal Aviation... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is..., Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. DATES: The meeting will be held...

  4. 77 FR 66084 - Tenth Meeting: RTCA Special Committee 225, Rechargeable Lithium Battery and Battery Systems-Small...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-01

    ... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size AGENCY: Federal Aviation... 225, Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. SUMMARY: The FAA is..., Rechargeable Lithium Battery and Battery Systems--Small and Medium Size. DATES: The meeting will be held...

  5. 77 FR 20688 - Seventh Meeting: RTCA Special Committee 225, Rechargeable Lithium Batteries and Battery Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... Committee 225, Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size AGENCY: Federal... Committee 225, Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size. SUMMARY: The FAA..., Rechargeable Lithium Batteries and Battery Systems, Small and Medium Size. DATES: The meeting will be held May...

  6. 76 FR 67019 - Eighty-Seventh: RTCA Special Committee 159: Global Positioning System (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... Committee 159: Global Positioning System (GPS) 87th meeting. DATES: The meeting will be held November 14-18... Committee 159, Global Positioning System (GPS). The agenda will include the following: November 14-17, 2011... Committee 159: Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), U.S...

  7. 75 FR 59327 - Seventh Meeting-RTCA Special Committee 217: Joint With EUROCAE WG-44 Terrain and Airport Mapping...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ... Headquarters, Wilbur Wright Room, 55 Invernes Drive East, Englewood, Colorado, 80112, USA, John Kasten, E-mail: [email protected] , telephone (303) 328-4535, mobile (303) 260-9652. Alternate Contact, Lisa Haskell, E- mail: lisa[email protected] , telephone (303) 328-6891. FOR FURTHER INFORMATION CONTACT...

  8. 77 FR 5615 - First Meeting: RTCA Special Committee 227, Standards of Navigation Performance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ... Performance--Background/History Review of SC 181 Products and Intended Applications Walk through of DO-236B... Responsibilities Any Other Business Establish Agenda for Next Meeting Date and Place of Next Meeting Adjourn... Washington, DC, on January 30, 2012. John Raper, Manager, Business Operations Branch, Federal Aviation...

  9. 78 FR 51809 - Seventeenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal... Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases. SUMMARY: The FAA is... Databases being held jointly with EUROCAE WG-44--Aeronautical Databases. DATES: The meeting will be held...

  10. 78 FR 8684 - Fifteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint with EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    ... Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases AGENCY: Federal... Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases. SUMMARY: The FAA is... Databases being held jointly with EUROCAE WG-44--Aeronautical Databases. DATES: The meeting will be held...

  11. 78 FR 25134 - Sixteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal... Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases. SUMMARY: The FAA is... Databases being held jointly with EUROCAE WG-44--Aeronautical Databases. DATES: The meeting will be held...

  12. 78 FR 66418 - Eighteenth Meeting: RTCA Special Committee 217-Aeronautical Databases Joint With EUROCAE WG-44...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ... Committee 217--Aeronautical Databases Joint With EUROCAE WG-44--Aeronautical Databases AGENCY: Federal... Committee 217--Aeronautical Databases Joint with EUROCAE WG-44--Aeronautical Databases. SUMMARY: The FAA is... Databases being held jointly with EUROCAE WG-44--Aeronautical Databases. DATES: The meeting will be held...

  13. 77 FR 14584 - Eleventh Meeting: RTCA Special Committee 217, Joint With EUROCAE Working Group-44, Terrain and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... Committee 217, Joint With EUROCAE Working Group--44, Terrain and Airport Mapping Databases AGENCY: Federal... Special Committee 217, Joint with EUROCAE Working Group--44, Terrain and Airport Mapping Databases... Committee 217, Joint with EUROCAE Working Group--44, Terrain and Airport Mapping Databases. DATES: The...

  14. 77 FR 36331 - Nineteenth Meeting: RTCA Special Committee 213, Enhanced Flight Vision Systems/Synthetic Vision...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... Document--Draft DO-XXX, Minimum Aviation Performance Standards (MASPS) for an Enhanced Flight Vision System... Discussion (9:00 a.m.-5:00 p.m.) Provide Comment Resolution of Document--Draft DO-XXX, Minimum Aviation.../Approve FRAC Draft for PMC Consideration--Draft DO- XXX, Minimum Aviation Performance Standards (MASPS...

  15. 75 FR 29810 - Sixth Meeting: RTCA Special Committee 221: Aircraft Secondary Barriers and Alternative Flight...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ... 221: Aircraft Secondary Barriers and Alternative Flight Deck Security Procedures. AGENCY: Federal... Secondary Barriers and Alternative Flight Deck Security Procedures. SUMMARY: The FAA is issuing this notice... Alternative Flight Deck Security Procedures. DATES: The meeting will be held June 15-16, 2010. June 15th from...

  16. 75 FR 44306 - Eleventh Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... Committee 213: EUROCAE WG- 79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY... Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS... 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The...

  17. 75 FR 71183 - Twelfth Meeting: Joint RTCA Special Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS) AGENCY... Committee 213: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). SUMMARY...: EUROCAE WG-79: Enhanced Flight Vision Systems/Synthetic Vision Systems (EFVS/SVS). DATES: The meeting will...

  18. 78 FR 22024 - Twenty First Meeting: RTCA Special Committee 216, Aeronautical Systems Security (Joint Meeting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... plenary Joint Plenary [cir] Subgroup status reports [cir] Review schedule and decide on readiness of documents for Final Review and Comment [cir] Identify next steps 3:00 p.m. (1500) Wrap-Up, Adjourn...: Monday, May 13, 2013 Introductions High-level document status Review level of maturity of contributions...

  19. 78 FR 22025 - Eighteenth Meeting: RTCA Special Committee 214, Standards for Air Traffic Data Communication...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... add to the SC deliverables Change 1 to DO-224C ``Singal-in-Space Minimum Aviation System Performance Standards (MASPS) for Advanced VHF Digital Data Communications Including Compatibility with Digital Voice... Performance Standards (MOPS) for Aircraft VDL Mode 2 Physical Link and Network Layer'' Other Business Adjourn...

  20. Human factors and operations issues in GPS and WAAS sensor approvals : a review and comparison of FAA and RTCA documents

    DOT National Transportation Integrated Search

    1997-07-01

    This report is the culmination of the first task in a project to evaluate human factors and operations issues associated with the integration of Class C Global Positioning System (GPS) sensors and Class Beta GPS/Wide Area Augmentation System (WAAS) s...

  1. 78 FR 69928 - 35th Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-21

    ...-Groups meetings SG4: SE2020 Eddy Dissipation Rate (EDR) Turbulence Project Plenary--SG3 Architecture Document FRAC Resolution 11 December Plenary--SG3 Architecture Document FRAC Resolution Sub-Group Meetings 12 December Plenary--SG3 Architecture Document FRAC Resolution Sub-Group Meetings 13 December Closing...

  2. 78 FR 51808 - 34th Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... to Support ATC Winds SC-214 Briefing TOR Changes Other business Sub-Groups meetings Sep 24-26... MET Delivery Architecture Recommendations review Sep 27, Friday, Closing Plenary Sub-Groups reports Appoval for AIS and MET Delivery Architecture Recommendations document to enter FRAC Action item review...

  3. 78 FR 20167 - 33rd Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... Other Business Sub-Groups meetings Break out, as necessary daily EDR Turbulence Standards Project Briefing from FAA SE2020 Team SG6 WG1 Architecture and MASPS presentations SG3 AIS and MET Services Delivery Architecture Recommendations Document Review (FRAC release approval). Closing Plenary--Sub-Groups...

  4. Modeling and Simulation Plans in Support of Low Cost, Size, Weight, and Power Surveillance Systems for Detecting and Tracking Non-Cooperative Aircraft

    NASA Technical Reports Server (NTRS)

    Wu, Gilbert; Santiago, Confesor

    2017-01-01

    RTCA Special Committee (SC) 228 has initiated a second phase for the development of minimum operational performance standards (MOPS) for UAS detect and avoid (DAA) systems. Technologies to enable UAS with less available Size, Weight, and Power (SWaP) will be considered. RTCA SC-228 has established sub-working groups and one of the sub-working groups is focused on aligning modeling and simulations activities across all participating committee members. This briefing will describe NASAs modeling and simulation plans for the development of performance standards for low cost, size, weight, and power (C-SWaP) surveillance systems that detect and track non-cooperative aircraft. The briefing will also describe the simulation platform NASA intends to use to support end-to-end verification and validation for these DAA systems. Lastly, the briefing will highlight the experiment plan for our first simulation study, and provide a high-level description of our future flight test plans. This briefing does not contain any results or data.

  5. Determination of Receiver Susceptibility to Radio Frequency Interference from Portable Electronic Devices

    NASA Technical Reports Server (NTRS)

    Nguyen, Truong X.; Ely, Jay J.

    2002-01-01

    With the increasing pressures to allow wireless devices on aircraft, the susceptibility of aircraft receivers to interference from Portable Electronic Devices (PEDs) becomes an increasing concern. Many investigations were conducted in the past, with limited success, to quantify device emissions, path loss, and receiver interference susceptibility thresholds. This paper outlines the recent effort in determining the receiver susceptibility thresholds for ILS, VOR and GPS systems. The effort primarily consists of analysis of data available openly as reported in many RTCA and ICAO documents as well as manufacturers data on receiver sensitivity. Shortcomings with the susceptibility threshold data reported in the RTCA documents are presented, and an approach for an in-depth study is suggested. In addition, intermodulation products were observed and demonstrated in a laboratory experiment when multiple PEDs were in the proximity of each other. These intermodulation effects generate spurious frequencies that may fall within aircraft communication or navigation bands causing undesirable effects. Results from a preliminary analysis are presented that show possible harmful combinations of PEDs and the potentially affected aircraft bands.

  6. Flight Test 4 Preliminary Results: NASA Ames SSI

    NASA Technical Reports Server (NTRS)

    Isaacson, Doug; Gong, Chester; Reardon, Scott; Santiago, Confesor

    2016-01-01

    Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements as well as the safety substantiation and end-to-end assessment of DAA system performance. The Unmanned Aircraft System (UAS) Integration into the National Airspace System (NAS) Project conducted flight test program, referred to as Flight Test 4, at Armstrong Flight Research Center from April -June 2016. Part of the test flights were dedicated to the NASA Ames-developed Detect and Avoid (DAA) System referred to as JADEM (Java Architecture for DAA Extensibility and Modeling). The encounter scenarios, which involved NASA's Ikhana UAS and a manned intruder aircraft, were designed to collect data on DAA system performance in real-world conditions and uncertainties with four different surveillance sensor systems. Flight test 4 has four objectives: (1) validate DAA requirements in stressing cases that drive MOPS requirements, including: high-speed cooperative intruder, low-speed non-cooperative intruder, high vertical closure rate encounter, and Mode CS-only intruder (i.e. without ADS-B), (2) validate TCASDAA alerting and guidance interoperability concept in the presence of realistic sensor, tracking and navigational errors and in multiple-intruder encounters against both cooperative and non-cooperative intruders, (3) validate Well Clear Recovery guidance in the presence of realistic sensor, tracking and navigational errors, and (4) validate DAA alerting and guidance requirements in the presence of realistic sensor, tracking and navigational errors. The results will be presented at RTCA Special Committee 228 in support of final verification and validation of the DAA MOPS.

  7. 76 FR 59481 - Fifty Eighth Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... Committee 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation...: Environmental Conditions and Test Procedures for Airborne Equipment. SUMMARY: The FAA is issuing this notice to... Procedures for Airborne Equipment DATES: The meeting will be held October 20, 2011 from 9 a.m.-5 p.m...

  8. 76 FR 22161 - Fifty Seventh Meeting: RTCA Special Committee 135, Environmental Conditions and Test Procedures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-20

    ... Committee 135, Environmental Conditions and Test Procedures for Airborne Equipment AGENCY: Federal Aviation...: Environmental Conditions and Test Procedures for Airborne Equipment. SUMMARY: The FAA is issuing this notice to... Procedures for Airborne Equipment. DATES: The meeting will be held May 11-12, 2011 from 9 a.m.-5 p.m...

  9. 75 FR 20423 - Tenth Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ..., Airport Data Base) Briefing from SC-186/WG-51 (CPDLC support for Interval Management) Review of the work... 214: Working Group 78: Standards for Air Traffic Data Communication Services AGENCY: Federal Aviation... Traffic Data Communication Services. SUMMARY: The FAA is issuing this notice to advise the public of a...

  10. 77 FR 54648 - Seventh Meeting: RTCA NextGen Advisory Committee (NAC)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-05

    ...' license/State-issued ID Card Number and State of Issuance Company Phone number contact Non-U.S. Citizens... can be used for NextGen Metrics Data Sources for Measuring NextGen Fuel Impact A discussion of a preliminary report on a critical data source to track and analyze the impact of NextGen Non-Technical Barriers...

  11. 77 FR 47492 - Thirteenth Meeting: RTCA Special Committee 217, Terrain and Airport Mapping Databases, Joint With...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-08

    ... Committee 217, Terrain and Airport Mapping Databases, Joint With EUROCAE WG-44 AGENCY: Federal Aviation... 217, Terrain and Airport Mapping Databases, Joint with EUROCAE WG-44. SUMMARY: The FAA is issuing this... Mapping Databases, Joint with EUROCAE WG-44. DATES: The meeting will be held September 10-14, 2012, from 9...

  12. 75 FR 71183 - 23rd Meeting: RTCA Special Committee 206: EUROCAE WG 76 Plenary: AIS and MET Data Link Services

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-22

    ... Services Delivery Architecture Recommendations are included in the TOR deliverables. The Concept of Use for... operating picture for evolving global ATM concepts. The AIS and MET Services Delivery Architecture... provides recommended alternatives for AIS and MET data delivery architectures. The Concept of Use and...

  13. Diversity of freshwater Epsilonproteobacteria and dark inorganic carbon fixation in the sulphidic redoxcline of a meromictic karstic lake.

    PubMed

    Noguerola, Imma; Picazo, Antonio; Llirós, Marc; Camacho, Antonio; Borrego, Carles M

    2015-07-01

    Sulfidic redoxclines are a suitable niche for the growth and activity of different chemo- and photolithotrophic sulphide-oxidizing microbial groups such as the Epsilonproteobacteria and the green sulfur bacteria (GSB). We have investigated the diversity, abundance and contribution to inorganic carbon uptake of Epsilonproteobacteria in a meromictic basin of Lake Banyoles. CARD-FISH counts revealed that Epsilonproteobacteria were prevalent at the redoxcline in winter (maximum abundance of 2 × 10(6) cells mL(-1), ≈60% of total cells) but they were nearly absent in summer, when GSB bloomed. This seasonal trend was supported by 16S rRNA gene pyrotag datasets, which revealed that the epsilonproteobacterial community was mainly composed of a member of the genus Arcobacter. In situ incubations using NaH(14)CO3 and MAR-CARD-FISH observations showed that this population assimilated CO2 in the dark, likely being mainly responsible for the autotrophic activity at the redoxcline in winter. Clone libraries targeting the aclB gene provided additional evidence of the potential capacity of these epsilonproteobacteria to fix carbon via rTCA cycle. Our data reinforce the key role of Epsilonproteobacteria in linking carbon and sulphur cycles, extend their influence to freshwater karstic lakes and raise questions about the actual contribution of chemolithotrophy at their redoxcline and euxinic water compartments. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Analysis of hyaluronic acid concentration in rat vocal folds during estral and gravidic puerperal cycles.

    PubMed

    Pedroso, José Eduardo de Sá; Brasil, Osíris Camponês do; Martins, João Roberto Maciel; Nader, Helena Bociane; Simões, Manuel de Jesus

    2009-01-01

    Hormone plays an important role in the larynx. Among other substances, vocal folds contain hyaluronic acid, which tissue concentration may vary according to hormone action. the objective of this study is to analyze hyaluronic acid concentration in the vocal folds during estral and gravidic-puerperal cycles. Experimental study. 40 adult rats were divided into two groups. In the first group we used 20 rats to establish the concentration of hyaluronic acid during the estral cycle and in the second group, 20 animals were submitted to the same procedure but during the gravidic-puerperal cycle. Variations in hyaluronic acid concentration was not observed during the estral cycle. In the gravidic puerperal cycle group, an increase in hyaluronic acid concentration was observed in the puerperal subgroup. Comparing the two groups of estral and gravidic-puerperal cycles, no difference was observed. In comparing all subgroups of estral and gravidic-puerperal cycles, an increase in hyaluronic acid concentration was noticed only in the puerperal phase.

  15. Toothpaste Prevents Debonded Brackets on Erosive Enamel

    PubMed Central

    Barros, Érico Luiz Damasceno; Pinto, Shelon Cristina Souza; Borges, Alvaro Henrique; Tonetto, Mateus Rodrigues; Ellwood, Roger Phillip; Pretty, Ian; Bandéca, Matheus Coelho

    2015-01-01

    This study evaluated the effect of high fluoride dentifrice on the bond strength of brackets after erosive challenge. Eighty-four enamel specimens were divided into seven groups (n = 12): WN (distilled water/no acid challenge), W3C (distilled water/3 cycles of acid challenge), and W6C (distilled water/6 cycles of acid challenge) were not submitted to dentifrice treatment. Groups RF3C (regular fluoride dentifrice/3 cycles of acid challenge) and RF6C (regular fluoride dentifrice/6 cycles of acid challenge) were treated with dentifrices containing 1450 μg F−/g and HF3C (high fluoride dentifrice/3 cycles of acid challenge) and HF6C (high fluoride dentifrice/6 cycles of acid challenge) were with 5000 μg F−/g. Acid challenges were performed for seven days. After bond strength test, there was no significant difference among groups submitted to 3 cycles of acid challenge (P > 0.05). Statistically significant difference was found between the regular and high fluoride dentifrices after 6 cycles of acid challenge (<0.05). Similar areas of adhesive remaining were found among control groups and among groups W6C, RF3C, RF6C, HF3C, and HF6C. The high fluoride dentifrice was able to prevent the reduction of bond strength values of brackets submitted to acid challenge. Clinical relevance: the high fluoride toothpaste prevents debonded brackets on erosive enamel. PMID:25879058

  16. 77 FR 20688 - 29th Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    .... SC-206 Related Work in SESAR--Progress Status. Discuss previously proposed TOR changes and DO-252 Revision. [cir] Discuss TOR changes for the June PMC meeting. PMC decision on OSED document. ConUse FRAC... dates. Decision to approve the ConUse document for release to the PMC. Agree upon TOR changes for June...

  17. 75 FR 28319 - Thirteenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... for collaboration or joint work. ED204-SG4: Review the SOW of both groups, determine if full or partly... the expectations of the audience well understood? How will the work progress, fully joint, partly... Publication (separate in ED210 or integrated). 11:00 to 11:15: Break. 11:15 to 11:30: Discuss collaboration...

  18. 75 FR 16901 - Thirteenth Meeting: EUROCAE WG-72: RTCA Special Committee 216: Aeronautical Systems Security...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-02

    ... basis for collaboration or joint work. ED204-SG4: Review the SOW of both groups, determine if full or... the expectations of the audience well understood? How will the work progress, fully joint, partly... Publication (separate in ED210 or integrated). 11:00 to 11:15: Break. 11:15 to 11:30: Discuss collaboration...

  19. 76 FR 70531 - Tenth Meeting: RTCA Special Committee 217/EUROCAE WG-44: Terrain and Airport Mapping Databases

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ... 217/EUROCAE WG-44: Terrain and Airport Mapping Databases AGENCY: Federal Aviation Administration (FAA... Databases: For the tenth meeting DATES: The meeting will be held December 6-9, 2011, from 9 a.m. to 5 p.m... Mapping Databases. The agenda will include the following: December 6, 2011 Open Plenary Session. Chairman...

  20. 77 FR 29749 - Twelfth Meeting: RTCA Special Committee 217, Joint with EUROCAE WG-44, Terrain and Airport...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... Committee 217, Joint with EUROCAE WG-44, Terrain and Airport Mapping Databases AGENCY: Federal Aviation... 217, Joint with EUROCAE WG-44, Terrain and Airport Mapping Databases. SUMMARY: The FAA is issuing this..., Terrain and Airport Mapping Databases. DATES: The meeting will be held June 18-22, 2012, from 9:00 a.m.-5...

  1. 77 FR 58210 - 31st Meeting: RTCA Special Committee 206, Aeronautical Information and Meteorological Data Link...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-19

    ... approve meeting agenda Action item review Sub-Group (SG1--Wake OSED, SG3--Architecture, SG4--DO-252... Architecture(s) AAtS Implementation Guidance Document New Capabilities in Flight Services 1 p.m. Opening... Action item review Future meeting plans and dates Other business 1 p.m. Adjourn (no lunch break) Welcome...

  2. Final Report - Regulatory Considerations for Adaptive Systems

    NASA Technical Reports Server (NTRS)

    Wilkinson, Chris; Lynch, Jonathan; Bharadwaj, Raj

    2013-01-01

    This report documents the findings of a preliminary research study into new approaches to the software design assurance of adaptive systems. We suggest a methodology to overcome the software validation and verification difficulties posed by the underlying assumption of non-adaptive software in the requirementsbased- testing verification methods in RTCA/DO-178B and C. An analysis of the relevant RTCA/DO-178B and C objectives is presented showing the reasons for the difficulties that arise in showing satisfaction of the objectives and suggested additional means by which they could be satisfied. We suggest that the software design assurance problem for adaptive systems is principally one of developing correct and complete high level requirements and system level constraints that define the necessary system functional and safety properties to assure the safe use of adaptive systems. We show how analytical techniques such as model based design, mathematical modeling and formal or formal-like methods can be used to both validate the high level functional and safety requirements, establish necessary constraints and provide the verification evidence for the satisfaction of requirements and constraints that supplements conventional testing. Finally the report identifies the follow-on research topics needed to implement this methodology.

  3. Metabolism: Part II. The Tricarboxylic Acid (TCA), Citric Acid, or Krebs Cycle.

    ERIC Educational Resources Information Center

    Bodner, George M.

    1986-01-01

    Differentiates the tricarboxylic acid (TCA) cycle (or Krebs cycle) from glycolysis, and describes the bridge between the two as being the conversion of pyruvate into acetyl coenzyme A. Discusses the eight steps in the TCA cycle, the results of isotopic labeling experiments, and the net effects of the TCA cycle. (TW)

  4. A reverse KREBS cycle in photosynthesis: consensus at last

    NASA Technical Reports Server (NTRS)

    Buchanan, B. B.; Arnon, D. I.

    1990-01-01

    The Krebs cycle (citric acid or tricarboxylic acid cycle), the final common pathway in aerobic metabolism for the oxidation of carbohydrates, fatty acids and amino acids, is known to be irreversible. It liberates CO2 and generates NADH whose aerobic oxidation yields ATP but it does not operate in reverse as a biosynthetic pathway for CO2 assimilation. In 1966, our laboratory described a cyclic pathway for CO2 assimilation (Evans, Buchanan and Arnon 1966) that was unusual in two respects: (i) it provided the first instance of an obligate photoautotroph that assimilated CO2 by a pathway different from Calvin's reductive pentose phosphate cycle (Calvin 1962) and (ii) in its overall effect the new cycle was a reversal of the Krebs cycle. Named the 'reductive carboxylic acid cycle' (sometimes also called the reductive tricarboxylic acid cycle) the new cycle appeared to be the sole CO2 assimilation pathway in Chlorobium thiosulfatophilum (Evans et al. 1966) (now known as Chlorobium limicola forma thiosulfatophilum). Chlorobium is a photosynthetic green sulfur bacterium that grows anaerobically in an inorganic medium with sulfide and thiosulfate as electron donors and CO2 as an obligatory carbon source. In the ensuing years, the new cycle was viewed with skepticism. Not only was it in conflict with the prevailing doctrine that the 'one important property ... shared by all (our emphasis) autotrophic species is the assimilation of CO2 via the Calvin cycle' (McFadden 1973) but also some of its experimental underpinnings were challenged. It is only now that in the words of one of its early skeptics (Tabita 1988) 'a long and tortuous controversy' has ended with general acceptance of the reductive carboxylic acid cycle as a photosynthetic CO2 assimilation pathway distinct from the pentose cycle. (Henceforth, to minimize repetitiveness, the reductive pentose phosphate cycle will often be referred to as the pentose cycle and the reductive carboxylic acid cycle as the carboxylic acid cycle.) Aside from photosynthetic pathways which are the focus of this article, CO2 assimilation is also known to sustain autotrophic growth via the acetyl-CoA pathway (Wood et al. 1986). Our aim here is to discuss (i) the findings that led our group to the discovery of the reductive carboxylic acid cycle, (ii) the nature and resolution of the controversy that followed, and (iii) the possible evolutionary implications of the cycle as an ancient mechanism for photosynthetic CO2 assimilation that preceded the pentose cycle and served as a precursor of the Krebs cycle in aerobic metabolism.

  5. A reverse KREBS cycle in photosynthesis: consensus at last.

    PubMed

    Buchanan, B B; Arnon, D I

    1990-01-01

    The Krebs cycle (citric acid or tricarboxylic acid cycle), the final common pathway in aerobic metabolism for the oxidation of carbohydrates, fatty acids and amino acids, is known to be irreversible. It liberates CO2 and generates NADH whose aerobic oxidation yields ATP but it does not operate in reverse as a biosynthetic pathway for CO2 assimilation. In 1966, our laboratory described a cyclic pathway for CO2 assimilation (Evans, Buchanan and Arnon 1966) that was unusual in two respects: (i) it provided the first instance of an obligate photoautotroph that assimilated CO2 by a pathway different from Calvin's reductive pentose phosphate cycle (Calvin 1962) and (ii) in its overall effect the new cycle was a reversal of the Krebs cycle. Named the 'reductive carboxylic acid cycle' (sometimes also called the reductive tricarboxylic acid cycle) the new cycle appeared to be the sole CO2 assimilation pathway in Chlorobium thiosulfatophilum (Evans et al. 1966) (now known as Chlorobium limicola forma thiosulfatophilum). Chlorobium is a photosynthetic green sulfur bacterium that grows anaerobically in an inorganic medium with sulfide and thiosulfate as electron donors and CO2 as an obligatory carbon source. In the ensuing years, the new cycle was viewed with skepticism. Not only was it in conflict with the prevailing doctrine that the 'one important property ... shared by all (our emphasis) autotrophic species is the assimilation of CO2 via the Calvin cycle' (McFadden 1973) but also some of its experimental underpinnings were challenged. It is only now that in the words of one of its early skeptics (Tabita 1988) 'a long and tortuous controversy' has ended with general acceptance of the reductive carboxylic acid cycle as a photosynthetic CO2 assimilation pathway distinct from the pentose cycle. (Henceforth, to minimize repetitiveness, the reductive pentose phosphate cycle will often be referred to as the pentose cycle and the reductive carboxylic acid cycle as the carboxylic acid cycle.) Aside from photosynthetic pathways which are the focus of this article, CO2 assimilation is also known to sustain autotrophic growth via the acetyl-CoA pathway (Wood et al. 1986). Our aim here is to discuss (i) the findings that led our group to the discovery of the reductive carboxylic acid cycle, (ii) the nature and resolution of the controversy that followed, and (iii) the possible evolutionary implications of the cycle as an ancient mechanism for photosynthetic CO2 assimilation that preceded the pentose cycle and served as a precursor of the Krebs cycle in aerobic metabolism.

  6. UAS NAS IHITL Test Readiness Review (TRR)

    NASA Technical Reports Server (NTRS)

    Murphy, Jim; Brignola, Michael P.; Rorie, Conrad; Santiago, Confesor; Guminsky, Mike; Cross, Ken

    2014-01-01

    Requesting release of IHITL test readiness review (TRR) charts to ensure UAS-NAS project primary stakeholders, the Federal Aviation Administration through the RTCA special committee -228 and the Office of the Secretary of Defense Sense and Avoid Science and Research Panel, are well informed on the IHITL test plan and expected outcomes as they relate to their needs to safely fly UAS in the NAS.

  7. 78 FR 57672 - 91st Meeting: RTCA Special Committee 159, Global Positioning Systems (GPS)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-19

    ... include the following: Working Group Sessions October 7 Working Group 2C, GPS/Inertial, ARINC & A4A Rooms October 8 Working Group 2, GPS/WAAS, McIntosh-NBAA Room and Colson Board Room October 9 Working Group 2, GPS/WAAS, ARINC & A4A Rooms, Afternoon, 1:00 p.m.-5:00 p.m., Working Group 4, GPS/Precision Landing...

  8. GPS/INS integration by functional partitioning

    NASA Astrophysics Data System (ADS)

    Diesel, John W.

    It is shown that a GPS/INS system integrated by functional partitioning can satisfy all of the RTCA navigation requirements and goals. This is accomplished by accurately calibrating the INS using GPS after the inertial instruments are thermally stabilized and by exploiting the very slow subsequent error growth in the INS information. In this way, autonomous integrity monitoring can be achieved using only existing or presently planned systems.

  9. Metabolic interaction between urea cycle and citric acid cycle shunt: A guided approach.

    PubMed

    Pesi, Rossana; Balestri, Francesco; Ipata, Piero L

    2018-03-01

    This article is a guided pedagogical approach, devoted to postgraduate students specializing in biochemistry, aimed at presenting all single reactions and overall equations leading to the metabolic interaction between ureagenesis and citric acid cycle to be incorporated into a two-three lecture series about the interaction of urea cycle with other metabolic pathways. We emphasize that citrate synthetase, aconitase, and isocitrate dehydrogenase, three enzymes of the citric acid cycle are not involved, thus creating a shunt in citric acid cycle. In contrast, the glutamic-oxaloacetate transaminase, which does not belong to citric acid cycle, has a paramount importance in the metabolic interaction of the two cycles, because it generates aspartate, one of the two fuel molecules of urea cycle, and a-ketoglutarate, an intermediate of the citric acid cycle. Finally, students should appreciate that balancing equations for all atoms and charges is not only a stoichiometric task, but strongly facilitates the discussion of the physiological roles of metabolic pathways. Indeed, this exercise has been used in the classroom, to encourage a deeper level of understanding of an important biochemical issue. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(2):182-185, 2018. © 2017 The International Union of Biochemistry and Molecular Biology.

  10. An investigation of the antibacterial ability and cytotoxicity of a novel cu-bearing 317L stainless steel

    NASA Astrophysics Data System (ADS)

    Sun, Da; Xu, Dake; Yang, Chunguang; Shahzad, M. Babar; Sun, Ziqing; Xia, Jin; Zhao, Jinlong; Gu, Tingyue; Yang, Ke; Wang, Guixue

    2016-07-01

    In order to solve the challenging problem of microbial infections caused by microorganisms on medical implants, it is imperative to develop novel antimicrobial biomaterials. This work demonstrated that 317L-Cu stainless steel (SS), created by adding copper through a solution and aging heat treatment process, exhibited good antibacterial properties against staphylococcus aureus, achieving 2 log reduction of planktonic cells after 5 days of incubation. In this study, the antibacterial test was performed using the plate count method, the fluorescence cell staining method and the quantitative polymerase chain reaction (qPCR) method. It is well known that a high concentration of copper ion can lead to cytotoxicity. This work explored the cytotoxicity of 317L-Cu SS through real-time cell analysis (RTCA). Experimental results demonstrated that the 317L-Cu SS possessed a satisfactory antibacterial ability against S. aureus, and the antibacterial rate based on the reduction of sessile cell count reached 98.3% after 24-hour treatment. The bacterial adhesion and the biofilm thickness were considerably reduced by the 317L-Cu SS. The results of RTCA suggested that 317L-Cu SS did not introduce cytotoxicity to mouse cells, indicating its suitability as a medical implant material.

  11. Analysis of UAS DAA Alerting in Fast-Time Simulations without DAA Mitigation

    NASA Technical Reports Server (NTRS)

    Thipphavong, David P.; Santiago, Confesor; Isaacson, Douglas R.; Lee, Seung Man; Park, Chunki; Refai, Mohamad Said; Snow, James

    2015-01-01

    Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA alerting system performance. A recent study conducted using NASA's ACES (Airspace Concept Evaluation System) simulation capability begins to address questions surrounding the development of draft MOPS for DAA alerting systems. ACES simulations were conducted to study the performance of alerting systems proposed by the SC-228 DAA Alerting sub-group. Analysis included but was not limited to: 1) correct alert (and timeliness), 2) false alert (and severity and duration), 3) missed alert, and 4) probability of an alert type at the time of loss of well clear. The performance of DAA alerting systems when using intent vs. dead-reckoning for UAS ownship trajectories was also compared. The results will be used by SC-228 to inform decisions about the surveillance standards of UAS DAA systems and future requirements development and validation efforts.

  12. Analysis of UAS DAA Surveillance in Fast-Time Simulations without DAA Mitigation

    NASA Technical Reports Server (NTRS)

    Thipphavong, David P.; Santiago, Confesor; Isaacson, David R.; Lee, Seung Man; Refai, Mohamad Said; Snow, James William

    2015-01-01

    Realization of the expected proliferation of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) depends on the development and validation of performance standards for UAS Detect and Avoid (DAA) Systems. The RTCA Special Committee 228 is charged with leading the development of draft Minimum Operational Performance Standards (MOPS) for UAS DAA Systems. NASA, as a participating member of RTCA SC-228 is committed to supporting the development and validation of draft requirements for DAA surveillance system performance. A recent study conducted using NASA's ACES (Airspace Concept Evaluation System) simulation capability begins to address questions surrounding the development of draft MOPS for DAA surveillance systems. ACES simulations were conducted to study the performance of sensor systems proposed by the SC-228 DAA Surveillance sub-group. Analysis included but was not limited to: 1) number of intruders (both IFR and VFR) detected by all sensors as a function of UAS flight time, 2) number of intruders (both IFR and VFR) detected by radar alone as a function of UAS flight time, and 3) number of VFR intruders detected by all sensors as a function of UAS flight time. The results will be used by SC-228 to inform decisions about the surveillance standards of UAS DAA systems and future requirements development and validation efforts.

  13. Serum uric acid in relation to endogenous reproductive hormones during the menstrual cycle: findings from the BioCycle study

    PubMed Central

    Mumford, Sunni L.; Dasharathy, Sonya S.; Pollack, Anna Z.; Perkins, Neil J.; Mattison, Donald R.; Cole, Stephen R.; Wactawski-Wende, Jean; Schisterman, Enrique F.

    2013-01-01

    STUDY QUESTION Do uric acid levels across the menstrual cycle show associations with endogenous estradiol (E2) and reproductive hormone concentrations in regularly menstruating women? SUMMARY ANSWER Mean uric acid concentrations were highest during the follicular phase, and were inversely associated with E2 and progesterone, and positively associated with FSH. WHAT IS KNOWN ALREADY E2 may decrease serum levels of uric acid in post-menopausal women; however, the interplay between endogenous reproductive hormones and uric acid levels among regularly menstruating women has not been elucidated. STUDY DESIGN, SIZE, DURATION The BioCycle study was a prospective cohort study conducted at the University at Buffalo research centre from 2005 to 2007, which followed healthy women for one (n = 9) or 2 (n = 250) menstrual cycle(s). PARTICIPANTS/MATERIALS, SETTING, METHODS Participants were healthy women aged 18–44 years. Hormones and uric acid were measured in serum eight times each cycle for up to two cycles. Marginal structural models with inverse probability of exposure weights were used to evaluate the associations between endogenous hormones and uric acid concentrations. MAIN RESULTS AND THE ROLE OF CHANCE Uric acid levels were observed to vary across the menstrual cycle, with the lowest levels observed during the luteal phase. Every log-unit increase in E2 was associated with a decrease in uric acid of 1.1% (β = −0.011; 95% confidence interval (CI): −0.019, −0.004; persistent-effects model), and for every log-unit increase in progesterone, uric acid decreased by ∼0.8% (β = −0.008; 95% CI: −0.012, −0.004; persistent-effects model). FSH was positively associated with uric acid concentrations, such that each log-unit increase was associated with a 1.6% increase in uric acid (β = 0.016; 95% CI: 0.005, 0.026; persistent-effects model). Progesterone and FSH were also associated with uric acid levels in acute-effects models. Of 509 cycles, 42 were anovulatory (8.3%). Higher uric acid levels were associated with increased odds of anovulation (odds ratio 2.39, 95% CI: 1.25, 4.56). LIMITATIONS, REASONS FOR CAUTION The change in uric acid levels among this cohort of healthy women was modest, and analysis was limited to two menstrual cycles. The women in this study were healthy and regularly menstruating, and as such there were few women with high uric acid levels and anovulatory cycles. WIDER IMPLICATIONS OF THE FINDINGS These findings demonstrate the importance of taking menstrual cycle phase into account when measuring uric acid in premenopausal women, and confirm the hypothesized beneficial lowering effects of endogenous E2 on uric acid levels. These findings suggest that there could be an underlying association affecting both sporadic anovulation and high uric acid levels among young, regularly menstruating women. Further studies are needed to confirm these findings and elucidate the connection between uric acid and reproductive and later cardiovascular health. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (contract # HHSN275200403394C). No competing interests declared. PMID:23562957

  14. Studies on the Growth Effects of the Canaline-Urea Cycle Amino Acids with Lemna minor L. 1

    PubMed Central

    Rosenthal, Gerald A.; Gulati, Dushyant K.; Sabharwal, P. S.

    1975-01-01

    The aquatic microphyte, Lemna minor L., was utilized to assess the relative toxicity and general growth effects of canavanine, canaline, ureidohomoserine (UHS), and canavaninosuccinate (CSA). These amino acids are constituents of the canaline-urea cycle and structural analogues of the ornithine-urea cycle amino acids. Comparative growth studies with L. minor revealed that the canaline-urea cycle amino acids are potent antimetabolites. With the exception of CSA, they are extremely toxic at a concentration of 5 μm. Over a concentration range of 1 to 4 μm, canavanine is the most growth-inhibiting of the canaline-urea cycle amino acids. At or above 5 μm, canavanine and canaline possess comparable toxicity. UHS is less growth-inhibiting than canavanine or canaline, and CSA is the least toxic of the canaline-urea cycle intermediates. PMID:16659316

  15. Metabolic engineering in the biotechnological production of organic acids in the tricarboxylic acid cycle of microorganisms: Advances and prospects.

    PubMed

    Yin, Xian; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Liu, Long; Chen, Jian

    2015-11-01

    Organic acids, which are chemically synthesized, are also natural intermediates in the metabolic pathways of microorganisms, among which the tricarboxylic acid (TCA) cycle is the most crucial route existing in almost all living organisms. Organic acids in the TCA cycle include citric acid, α-ketoglutaric acid, succinic acid, fumaric acid, l-malic acid, and oxaloacetate, which are building-block chemicals with wide applications and huge markets. In this review, we summarize the synthesis pathways of these organic acids and review recent advances in metabolic engineering strategies that enhance organic acid production. We also propose further improvements for the production of organic acids with systems and synthetic biology-guided metabolic engineering strategies. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Testing of sealed lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Bush, D. M.; Sealey, J. D.; Miller, D. W.

    1984-02-01

    Sealed lead acid batteries under development were tested. The goal was to develop a totally maintenance free sealed lead acid battery capable of deep discharge operation in a photovoltaic power system. Sealed lead acid batteries and a group of conventional, flooded lead acid batteries were exposed to a matrix test plan, with some approaching 1000 cycles. This performance was achieved with the standard National Electrical Manufacturers' Association cycle test, and the partial state of charge cycle test. Modes of failure are investigated.

  17. A new approach to equipment testing

    NASA Technical Reports Server (NTRS)

    Hardwick, C. J.; Dunkley, V. P.; Burrows, B. J. C.; Darney, I.

    1991-01-01

    Considerable controversy has arisen during the recent discussions over a new version of the RTCA DO160C/ED 14C Section 22 document at the European Committee for Aviation Electronics. Section 22 is concerned with lightning waveform tests to equipment. Investigations of some of these controversies with circuit analysis and measurements indicate the impedance characteristics required of the transient generators and the possibility of testing to a voltage limit even for current waveforms.

  18. 75 FR 51332 - Eleventh Meeting: RTCA Special Committee 209: In Joint Session With EUROCAE WG-49: ATCRBS/Mode S...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ... of the Minutes of Meeting 10 (SC209-WP11-02) Review of the Status of Open Action Items AI-10-11--Review of Documents for P5 Pulse Position Differences (WP11-03) AI-10-03--Issues Related to Zeroing Registers 08 16 & 20 16 (WP11-04) AI-10-02--Register 60 16 Maximum Update Interval Changes (WP11-05) AI-10...

  19. A new approach to equipment testing

    NASA Astrophysics Data System (ADS)

    Hardwick, C. J.; Dunkley, V. P.; Burrows, B. J. C.; Darney, I.

    1991-08-01

    Considerable controversy has arisen during the recent discussions over a new version of the RTCA DO160C/ED 14C Section 22 document at the European Committee for Aviation Electronics. Section 22 is concerned with lightning waveform tests to equipment. Investigations of some of these controversies with circuit analysis and measurements indicate the impedance characteristics required of the transient generators and the possibility of testing to a voltage limit even for current waveforms.

  20. Genetics Home Reference: hereditary paraganglioma-pheochromocytoma

    MedlinePlus

    ... two important cellular pathways called the citric acid cycle (or Krebs cycle) and oxidative phosphorylation. These pathways are critical in ... can use. As part of the citric acid cycle, the SDH enzyme converts a compound called succinate ...

  1. ASSIP Study of Real-Time Safety-Critical Embedded Software-Intensive System Engineering Practices

    DTIC Science & Technology

    2008-02-01

    and assessment 2. product engineering processes 3. tooling processes 6 | CMU/SEI-2008-SR-001 Slide 1 Process Standards IEC/ ISO 12207 Software...and technical effort to align with 12207 IEC/ ISO 15026 System & Software Integrity Levels Generic Safety SAE ARP 4754 Certification Considerations...Process Frameworks in revision – ISO 9001, ISO 9004 – ISO 15288/ ISO 12207 harmonization – RTCA DO-178B, MOD Standard UK 00-56/3, … • Methods & Tools

  2. Monitoring of Viral Induced Cell Death Using Real Time Cell Analysis

    DTIC Science & Technology

    2016-11-01

    studies have shown that real- time cell analysis (RTCA) platforms such as the xCELLigence can be used to gather quantitative measurements of viral...Teng, Z., Kuang, X., Wang, J., Zhang, X. Real- time cell analysis – A new method for dynamic, quantitative measurement of infectious viruses and...cytopathogenicity. A) Real- time monitoring of BSR cells infected with a 1:10 dilution series of Gan Gan virus. The curve is an average of eight

  3. Equipment testing with damped sinewaves between 1 and 50 MHz

    NASA Astrophysics Data System (ADS)

    Hardwick, C. John; Baldwin, R. E.

    1992-11-01

    Present lightning equipment test standards such as RTCA DO160C call for damped sinusoidal tests at 1 and 10 MHz. There has been some discussion in the lightning community about extending these tests to 50 frequencies in the region 1-50 MHz. This paper presents characteristics of such tests on cable bundles and notes the relationship between bundle current and injected voltage; important parameters are the cable loss and Q of the driving waveform.

  4. Development of Intent Information Changes to Revised Minimum Aviation System Performance Standards for Automatic Dependent Surveillance Broadcast (RTCA/DO-242A)

    NASA Technical Reports Server (NTRS)

    Barhydt, Richard; Warren, Anthony W.

    2002-01-01

    RTCA Special Committee 186 has recently adopted a series of changes to the original Minimum Aviation System Performance Standards (MASPS) for Automatic Dependent Surveillance Broadcast (ADS-B). The new document will be published as DO-242A. Major changes to the MASPS include a significant restructuring and expansion of the intent parameters for future ADS-B systems. ADS-B provides a means for aircraft to exchange information about their intended trajectories with each other and with ground systems. NASA and Boeing have played significant roles in recommending these changes and providing supporting analysis. The intent changes are anticipated to provide substantial benefits to several programs and operational concepts under development by the two organizations. Major changes include the addition of Target State reports and the replacement of Trajectory Change Point reports with Trajectory Change reports. These changes have been designed to better reflect the capabilities of existing and future aircraft avionics, while providing benefits to current and proposed applications. DO-242A implements intent information elements that can be supported by current avionics systems and data buses. Provisions are made for future incorporation of other intent elements, as needed to meet operational requirements. This document summarizes the reasons for the DO-242A intent changes and provides a detailed overview of current and future intended ADS-B MASPS changes related to aircraft intent.

  5. Monitoring in real time the effect of TLX overexpression on proliferation and migration of C6 cells.

    PubMed

    Li, G L; Fang, S H; Xu, B

    2017-01-01

    Orphan nuclear receptor TLX has been shown to play an essential role in regulating the self-renewal and proliferation of neural stem cells (NSCs). However, TLX overexpression in NSCs induces long-term NSC expansion and further leads to glioma initiation in mouse when combined with p53 mutations. Whether overexpression of TLX plays a role in glioma stem cell (GSC) proliferation and migration still remains largely unknown. In this study, we infected C6 cells, a special glioma cell line which is mainly composed of cancer stem cells(CSCs), with lentiviruses expressing GFP(LV-GFP) or GFP-T2A-TLX(LV-TLX) and then monitored cell proliferation and migration using the real-time analyzer system (RTCA, xCELLigence, Roche). We found that the cell index (CI) observed for the TLX overexpressing C6 cells showed a lower value than that of the LV-GFP transduced cells. And the MTT results correlated highly with the RTCA proliferation assessments. Furthermore, the expression of p21 was decreased while other downstream genes PTEN and p53 were not significantly changed in TLX overexpressing C6 cells . These findings strongly indicate that TLX overexpression has the ability to decrease the proliferating and migratory properties of C6 cells by targeting p21. Further, our results suggest that TLX overexpression may also have a similar inhibitory effect on GSC proliferation and migration.

  6. Closed cycle ion exchange method for regenerating acids, bases and salts

    DOEpatents

    Dreyfuss, Robert M.

    1976-01-01

    A method for conducting a chemical reaction in acidic, basic, or neutral solution as required and then regenerating the acid, base, or salt by means of ion exchange in a closed cycle reaction sequence which comprises contacting the spent acid, base, or salt with an ion exchanger, preferably a synthetic organic ion-exchange resin, so selected that the counter ions thereof are ions also produced as a by-product in the closed reaction cycle, and then regenerating the spent ion exchanger by contact with the by-product counter ions. The method is particularly applicable to closed cycle processes for the thermochemical production of hydrogen.

  7. Cell cycle nucleic acids, polypeptides and uses thereof

    DOEpatents

    Gordon-Kamm, William J [Urbandale, IA; Lowe, Keith S [Johnston, IA; Larkins, Brian A [Tucson, AZ; Dilkes, Brian R [Tucson, AZ; Sun, Yuejin [Westfield, IN

    2007-08-14

    The invention provides isolated nucleic acids and their encoded proteins that are involved in cell cycle regulation. The invention further provides recombinant expression cassettes, host cells, transgenic plants, and antibody compositions. The present invention provides methods and compositions relating to altering cell cycle protein content, cell cycle progression, cell number and/or composition of plants.

  8. Profiles of the biosynthesis and metabolism of pyridine nucleotides in potatoes (Solanum tuberosum L.).

    PubMed

    Katahira, Riko; Ashihara, Hiroshi

    2009-12-01

    As part of a research program on nucleotide metabolism in potato tubers (Solanum tuberosum L.), profiles of pyridine (nicotinamide) metabolism were examined based on the in situ metabolic fate of radio-labelled precursors and the in vitro activities of enzymes. In potato tubers, [(3)H]quinolinic acid, which is an intermediate of de novo pyridine nucleotide synthesis, and [(14)C]nicotinamide, a catabolite of NAD, were utilised for pyridine nucleotide synthesis. The in situ tracer experiments and in vitro enzyme assays suggest the operation of multiple pyridine nucleotide cycles. In addition to the previously proposed cycle consisting of seven metabolites, we found a new cycle that includes newly discovered nicotinamide riboside deaminase which is also functional in potato tubers. This cycle bypasses nicotinamide and nicotinic acid; it is NAD --> nicotinamide mononucleotide --> nicotinamide riboside --> nicotinic acid riboside --> nicotinic acid mononucleotide --> nicotinic acid adenine dinucleotide --> NAD. Degradation of the pyridine ring was extremely low in potato tubers. Nicotinic acid glucoside is formed from nicotinic acid in potato tubers. Comparative studies of [carboxyl-(14)C]nicotinic acid metabolism indicate that nicotinic acid is converted to nicotinic acid glucoside in all organs of potato plants. Trigonelline synthesis from [carboxyl-(14)C]nicotinic acid was also found. Conversion was greater in green parts of plants, such as leaves and stem, than in underground parts of potato plants. Nicotinic acid utilised for the biosynthesis of these conjugates seems to be derived not only from the pyridine nucleotide cycle, but also from the de novo synthesis of nicotinic acid mononucleotide.

  9. Ectopic Bone Matrix Mineralization: Unveiling the Osteoinductive Nature of Crab Cuticle

    NASA Astrophysics Data System (ADS)

    Omokanwaye, Tiffany Suella

    Engineered nanomaterials are increasingly used in a variety of industrial processes and consumer products. Numerous studies have reported toxicity of different NPs during the last years. Thus, there are growing concerns about the potential impacts to the health and environment of engineered nanoparticles (NPs). However, some methodological problems complicate the interpretation of nanotoxicity studies. On the one hand, some NPs have shown to interfere with classical toxicity assays based on colorimetric or fluorescent measurements. On the other hand, most NPs tend to aggregate in media used in toxicity tests, which complicates the interpretation of the toxicity results. The first objective of this dissertation was to evaluate a novel impedance-based and label-free real time cell analyzer (RTCA) as a high throughput method for screening the cytotoxicity of nanoparticles and to validate the RTCA results using a conventional cytotoxicity test (MTT). Several inorganic NPs were tested for potential cytotoxicity to human bronchial epithelial cells (16HBE14o-). In general, there was a good correlation in cytotoxicity measurements between the two methods. Moreover, none of the NPs tested showed interference with the impedance measurements performed by the RTCA system. The results demonstrate the potential and validity of the impedance-based RTCA technique to rapidly screen for NP toxicity. The second objective of this dissertation was to assess the toxicity of different inorganic NPs to the eukaryotic cell model Saccharomyces cerevisiae, and to test the influence of NP aggregation state in their toxicity. Nanotoxicity was assessed by monitoring oxygen consumption in batch cultures and by analysis of cell membrane integrity. Mn2O3 NPs showed the highest inhibition of O2 consumption and cell membrane damage, while the other NPs caused low or no toxicity to the yeast. Most NPs showed high tendency to aggregate in the assay medium, so a non-toxic dispersant was used to improve NP stability. In contrast to aggregated CeO2 NPs, dispersed CeO 2 NPs showed toxicity to the yeast. However, dispersant supplementation decreased the inhibition caused by Mn2O3 NPs at low concentrations, which could indicate that dispersant association with the particles may have an impact on the interaction between the NPs and the cells. The proven toxicity of some NPs raises concerns about their environmental fate. Municipal and industrial wastewaters are considered primary sources of NPs to the environment. However, information on the behavior and impact of NPs on wastewater treatment processes is very limited. A third objective of this dissertation was to evaluate the fate and long-term effect of ZnO and CuO NPs during wastewater treatment in high-rate anaerobic bioreactors. Laboratory-scale upflow anaerobic sludge blanket (UASB) reactors were fed with synthetic wastewater containing NPs for extended periods of time (> 90 d). Extensive removal (62-82%) of ZnO and CuO NPs was observed during wastewater treatment in the UASB reactors. Scanning electron microscopy and chemical analysis confirmed that NPs were associated with the anaerobic sludge. While short-term exposure to low levels of ZnO and CuO NPs only caused minor inhibition to methanogenesis, extended exposure to NPs accumulated in the sludge bed led to a gradual and partial inhibitory response in the reactors. The inhibitory effect was also evident in the decline in the acetoclastic methanogenic activity of the biomass.

  10. Proteomic analysis of the molecular response of Raji cells to maslinic acid treatment.

    PubMed

    Yap, W H; Khoo, K S; Lim, S H; Yeo, C C; Lim, Y M

    2012-01-15

    Maslinic acid, a natural pentacyclic triterpene has been shown to inhibit growth and induce apoptosis in some tumour cell lines. We studied the molecular response of Raji cells towards maslinic acid treatment. A proteomics approach was employed to identify the target proteins. Seventeen differentially expressed proteins including those involved in DNA replication, microtubule filament assembly, nucleo-cytoplasmic trafficking, cell signaling, energy metabolism and cytoskeletal organization were identified by MALDI TOF-TOF MS. The down-regulation of stathmin, Ran GTPase activating protein-1 (RanBP1), and microtubule associated protein RP/EB family member 1 (EB1) were confirmed by Western blotting. The study of the effect of maslinic acid on Raji cell cycle regulation showed that it induced a G1 cell cycle arrest. The differential proteomic changes in maslinic acid-treated Raji cells demonstrated that it also inhibited expression of dUTPase and stathmin which are known to induce early S and G2 cell cycle arrests. The mechanism of maslinic acid-induced cell cycle arrest may be mediated by inhibiting cyclin D1 expression and enhancing the levels of cell cycle-dependent kinase (CDK) inhibitor p21 protein. Maslinic acid suppressed nuclear factor-kappa B (NF-κB) activity which is known to stimulate expression of anti-apoptotic and cell cycle regulatory gene products. These results suggest that maslinic acid affects multiple signaling molecules and inhibits fundamental pathways regulating cell growth and survival in Raji cells. Copyright © 2011 Elsevier GmbH. All rights reserved.

  11. Metabolic Interaction between Urea Cycle and Citric Acid Cycle Shunt: A Guided Approach

    ERIC Educational Resources Information Center

    Pesi, Rossana; Balestri, Francesco; Ipata, Piero L.

    2018-01-01

    This article is a guided pedagogical approach, devoted to postgraduate students specializing in biochemistry, aimed at presenting all single reactions and overall equations leading to the metabolic interaction between ureagenesis and citric acid cycle to be incorporated into a two-three lecture series about the interaction of urea cycle with other…

  12. Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project: Detect and Avoid Display Evaluations in Support of SC-228 Minimum Operational Performance Standards Development

    NASA Technical Reports Server (NTRS)

    Fern, Lisa Carolynn

    2017-01-01

    The primary activity for the UAS-NAS Human Systems Integration (HSI) sub-project in Phase 1 was support of RTCA Special Committee 228 Minimum Operational Performance Standards (MOPS). We provide data on the effect of various Detect and Avoid (DAA) display features with respect to pilot performance of the remain well clear function in order to determine the minimum requirements for DAA displays.

  13. USAF Airborne Sense and Avoid (ABSAA) Airworthiness and Operational Approval Approach. Version 1.0

    DTIC Science & Technology

    2014-01-31

    in, Class A or Special Use Airspace. The scope is also limited to larger UAS flying Instrument Flight Rules ( IFR ).16 If the civil standards do not...91.119 ( IFR operations along all-weather low-altitude routes).21 The history of the exemption from 14 CFR 91.209 related to NVG operations without... impact and schedule of a possible Part 91 rule change. The ABSAA PM should work to ensure appropriate FAA participation in RTCA activities to enable

  14. Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project

    NASA Technical Reports Server (NTRS)

    Fern, Lisa

    2017-01-01

    This presentation summarizes the simulation work conducted by the Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project. It focuses on the contribution of that research to the development of RTCA Special Committee 228's (SC-228) Minimum Operational Performance Standards (MOPS) for UAS. The research objectives and primary findings from four different human-in-the-loop simulations are discussed, along with the specific requirements these studies led to in the final MOPS document.

  15. Technologies for user-preferred routing

    NASA Astrophysics Data System (ADS)

    McNally, B. D.; Sridhar, Banavar

    1996-05-01

    The 1995 report of the RTCA Board of Directors' Select Committee on Free Flight states that 'insufficient capacity, limited access, and excessive operating restrictions have escalated operating costs, increase delays, and decreased efficiency for all users' of the national airspace system. The Air Transport Association estimates the annual loss to be 3.5 billion dollars. The goal of the user preferred routing research is to develop integrated airborne and ground technologies that enable the highest possible level of unconstrained, user-preferred routing in enroute airspace.

  16. FY13 GLYCOLIC-NITRIC ACID FLOWSHEET DEMONSTRATIONS OF THE DWPF CHEMICAL PROCESS CELL WITH SIMULANTS

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

    Lambert, D.; Zamecnik, J.; Best, D.

    Savannah River Remediation is evaluating changes to its current Defense Waste Processing Facility flowsheet to replace formic acid with glycolic acid in order to improve processing cycle times and decrease by approximately 100x the production of hydrogen, a potentially flammable gas. Higher throughput is needed in the Chemical Processing Cell since the installation of the bubblers into the melter has increased melt rate. Due to the significant maintenance required for the safety significant gas chromatographs and the potential for production of flammable quantities of hydrogen, eliminating the use of formic acid is highly desirable. Previous testing at the Savannah Rivermore » National Laboratory has shown that replacing formic acid with glycolic acid allows the reduction and removal of mercury without significant catalytic hydrogen generation. Five back-to-back Sludge Receipt and Adjustment Tank (SRAT) cycles and four back-to-back Slurry Mix Evaporator (SME) cycles were successful in demonstrating the viability of the nitric/glycolic acid flowsheet. The testing was completed in FY13 to determine the impact of process heels (approximately 25% of the material is left behind after transfers). In addition, back-to-back experiments might identify longer-term processing problems. The testing was designed to be prototypic by including sludge simulant, Actinide Removal Product simulant, nitric acid, glycolic acid, and Strip Effluent simulant containing Next Generation Solvent in the SRAT processing and SRAT product simulant, decontamination frit slurry, and process frit slurry in the SME processing. A heel was produced in the first cycle and each subsequent cycle utilized the remaining heel from the previous cycle. Lower SRAT purges were utilized due to the low hydrogen generation. Design basis addition rates and boilup rates were used so the processing time was shorter than current processing rates.« less

  17. Tandem dissolution of UO 3 in amide-based acidic ionic liquid and in situ electrodeposition of UO 2 with regeneration of the ionic liquid: a closed cycle

    DOE PAGES

    Wanigasekara, Eranda; Freiderich, John W.; Sun, Xiao-Guang; ...

    2016-05-19

    A closed cycle is demonstrated for the tandem dissolution and electroreduction of UO 3 to UO 2 with regeneration of the acidic ionic liquid. The dissolution is achieved by use of the acidic ionic liquid N,N-dimethylacetimidium bis(trifluoromethanesulfonimide) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonimide) serving as the diluent. Bulk electrolysis performed at 1.0 V vs. Ag reference yields a dark brown-black uranium deposit (UO 2) on the cathode. Anodic oxidation of water in the presence of dimethylacetamide regenerates the acidic ionic liquid. We have demonstrated the individual steps in the cycle together with a sequential dissolution, electroreduction, and regeneration cycle.

  18. Tandem dissolution of UO 3 in amide-based acidic ionic liquid and in situ electrodeposition of UO 2 with regeneration of the ionic liquid: a closed cycle

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

    Wanigasekara, Eranda; Freiderich, John W.; Sun, Xiao-Guang

    A closed cycle is demonstrated for the tandem dissolution and electroreduction of UO 3 to UO 2 with regeneration of the acidic ionic liquid. The dissolution is achieved by use of the acidic ionic liquid N,N-dimethylacetimidium bis(trifluoromethanesulfonimide) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonimide) serving as the diluent. Bulk electrolysis performed at 1.0 V vs. Ag reference yields a dark brown-black uranium deposit (UO 2) on the cathode. Anodic oxidation of water in the presence of dimethylacetamide regenerates the acidic ionic liquid. We have demonstrated the individual steps in the cycle together with a sequential dissolution, electroreduction, and regeneration cycle.

  19. Clinical benefit using sperm hyaluronic acid binding technique in ICSI cycles: a systematic review and meta-analysis.

    PubMed

    Beck-Fruchter, Ronit; Shalev, Eliezer; Weiss, Amir

    2016-03-01

    The human oocyte is surrounded by hyaluronic acid, which acts as a natural selector of spermatozoa. Human sperm that express hyaluronic acid receptors and bind to hyaluronic acid have normal shape, minimal DNA fragmentation and low frequency of chromosomal aneuploidies. Use of hyaluronic acid binding assays in intracytoplasmic sperm injection (ICSI) cycles to improve clinical outcomes has been studied, although none of these studies had sufficient statistical power. In this systematic review and meta-analysis, electronic databases were searched up to June 2015 to identify studies of ICSI cycles in which spermatozoa able to bind hyaluronic acid was selected. The main outcomes were fertilization rate and clinical pregnancy rate. Secondary outcomes included cleavage rate, embryo quality, implantation rate, spontaneous abortion and live birth rate. Seven studies and 1437 cycles were included. Use of hyaluronic acid binding sperm selection technique yielded no improvement in fertilization and pregnancy rates. A meta-analysis of all available studies showed an improvement in embryo quality and implantation rate; an analysis of prospective studies only showed an improvement in embryo quality. Evidence does not support routine use of hyaluronic acid binding assays in all ICSI cycles. Identification of patients that might benefit from this technique needs further study. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  20. Geobiochemistry of metabolism: Standard state thermodynamic properties of the citric acid cycle

    NASA Astrophysics Data System (ADS)

    Canovas, Peter A.; Shock, Everett L.

    2016-12-01

    Integrating microbial metabolism into geochemical modeling allows assessments of energy and mass transfer between the geosphere and the microbial biosphere. Energy and power supplies and demands can be assessed from analytical geochemical data given thermodynamic data for compounds involved in catabolism and anabolism. Results are reported here from a critique of the available standard state thermodynamic data for organic acids and acid anions involved in the citric acid cycle (also known as the tricarboxylic acid cycle or the Krebs cycle). The development of methods for estimating standard state data unavailable from experiments is described, together with methods to predict corresponding values at elevated temperatures and pressures using the revised Helgeson-Kirkham-Flowers (HKF) equation of state for aqueous species. Internal consistency is maintained with standard state thermodynamic data for organic and inorganic aqueous species commonly used in geochemical modeling efforts. Standard state data and revised-HKF parameters are used to predict equilibrium dissociation constants for the organic acids in the citric acid cycle, and to assess standard Gibbs energies of reactions for each step in the cycle at elevated temperatures and pressures. The results presented here can be used with analytical data from natural and experimental systems to assess the energy and power demands of microorganisms throughout the habitable ranges of pressure and temperature, and to assess the consequences of abiotic organic compound alteration processes at conditions of subsurface aquifers, sedimentary basins, hydrothermal systems, meteorite parent bodies, and ocean worlds throughout the solar system.

  1. p21 induction plays a dual role in anti-cancer activity of ursolic acid

    PubMed Central

    Zhang, Xudong; Song, Xinhua; Yin, Shutao; Zhao, Chong; Fan, Lihong

    2015-01-01

    Previous studies have shown that induction of G1 arrest and apoptosis by ursolic acid is associated with up-regulation of cyclin-dependent kinase inhibitor (CDKI) protein p21 in multiple types of cancer cells. However, the functional role of p21 induction in G1 cell cycle arrest and apoptosis, and the mechanisms of p21 induction by ursolic acid have not been critically addressed. In the current study, we demonstrated that p21 played a mediator role in G1 cell cycle arrest by ursolic acid, whereas p21-mediated up-regulation of Mcl-1 compromised apoptotic effect of ursolic acid. These results suggest that p21 induction plays a dual role in the anti-cancer activity of ursolic acid in terms of cell cycle and apoptosis regulation. p21 induction by ursolic acid was attributed to p53 transcriptional activation. Moreover, we found that ursolic acid was able to inhibit murine double minute-2 protein (MDM2) and T-LAK cell-originated protein kinase (TOPK), the two negative regulator of p53, which in turn contributed to ursolic acid-induced p53 activation. Our findings provided novel insights into understanding of the mechanisms involved in cell cycle arrest and apoptosis induction in response to ursolic acid exposure. PMID:26582056

  2. Linked cycles of oxidative decarboxylation of glyoxylate as protometabolic analogs of the citric acid cycle.

    PubMed

    Springsteen, Greg; Yerabolu, Jayasudhan Reddy; Nelson, Julia; Rhea, Chandler Joel; Krishnamurthy, Ramanarayanan

    2018-01-08

    The development of metabolic approaches towards understanding the origins of life, which have focused mainly on the citric acid (TCA) cycle, have languished-primarily due to a lack of experimentally demonstrable and sustainable cycle(s) of reactions. We show here the existence of a protometabolic analog of the TCA involving two linked cycles, which convert glyoxylate into CO 2 and produce aspartic acid in the presence of ammonia. The reactions proceed from either pyruvate, oxaloacetate or malonate in the presence of glyoxylate as the carbon source and hydrogen peroxide as the oxidant under neutral aqueous conditions and at mild temperatures. The reaction pathway demonstrates turnover under controlled conditions. These results indicate that simpler versions of metabolic cycles could have emerged under potential prebiotic conditions, laying the foundation for the appearance of more sophisticated metabolic pathways once control by (polymeric) catalysts became available.

  3. Blood metabolomics analysis identifies abnormalities in the citric acid cycle, urea cycle, and amino acid metabolism in bipolar disorder.

    PubMed

    Yoshimi, Noriko; Futamura, Takashi; Kakumoto, Keiji; Salehi, Alireza M; Sellgren, Carl M; Holmén-Larsson, Jessica; Jakobsson, Joel; Pålsson, Erik; Landén, Mikael; Hashimoto, Kenji

    2016-06-01

    Bipolar disorder (BD) is a severe and debilitating psychiatric disorder. However, the precise biological basis remains unknown, hampering the search for novel biomarkers. We performed a metabolomics analysis to discover novel peripheral biomarkers for BD. We quantified serum levels of 116 metabolites in mood-stabilized male BD patients (n = 54) and age-matched male healthy controls (n = 39). After multivariate logistic regression, serum levels of pyruvate, N-acetylglutamic acid, α-ketoglutarate, and arginine were significantly higher in BD patients than in healthy controls. Conversely, serum levels of β-alanine, and serine were significantly lower in BD patients than in healthy controls. Chronic (4-weeks) administration of lithium or valproic acid to adult male rats did not alter serum levels of pyruvate, N-acetylglutamic acid, β-alanine, serine, or arginine, but lithium administration significantly increased serum levels of α-ketoglutarate. The metabolomics analysis demonstrated altered serum levels of pyruvate, N-acetylglutamic acid, β-alanine, serine, and arginine in BD patients. The present findings suggest that abnormalities in the citric acid cycle, urea cycle, and amino acid metabolism play a role in the pathogenesis of BD.

  4. Extending food deprivation reverses the short-term lipolytic response to fasting: role of the triacylglycerol/fatty acid cycle.

    PubMed

    Weber, Jean-Michel; Reidy, Shannon P

    2012-05-01

    The effects of short-term food deprivation on lipid metabolism are well documented, but little is known about prolonged fasting. This study monitored the kinetics of glycerol (rate of appearance, R(a) glycerol) and non-esterified fatty acids (R(a) NEFA) in fasting rabbits. Our goals were to determine whether lipolysis is stimulated beyond values seen for short-term fasting, and to characterize the roles of primary (intracellular) and secondary (with transit through the circulation) triacylglycerol/fatty acid cycling (TAG/FA cycling) in regulating fatty acid allocation to oxidation or re-esterification. R(a) glycerol (9.62±0.72 to 15.29±0.96 μmol kg(-1) min(-1)) and R(a) NEFA (18.05±2.55 to 31.25±1.93 μmol kg(-1) min(-1)) were stimulated during the first 2 days of fasting, but returned to baseline after 4 days. An initial increase in TAG/FA cycling was followed by a reduction below baseline after 6 days without food, with primary and secondary cycling contributing to these responses. We conclude that the classic activation of lipolysis caused by short-term fasting is abolished when food deprivation is prolonged. High rates of re-esterification may become impossible to sustain, and TAG/FA cycling could decrease to reduce its cost to 3% of total energy expenditure. Throughout prolonged fasting, fatty acid metabolism gradually shifts towards increased oxidation and reduced re-esterification. Survival is achieved by pressing fuel selection towards the fatty acid dominance of energy metabolism and by slowing substrate cycles to assist metabolic suppression. However, TAG/FA cycling remains active even after prolonged fasting, suggesting that re-esterification is a crucial mechanism that cannot be stopped without harmful consequences.

  5. Activation and Repression of Epstein-Barr Virus and Kaposi's Sarcoma-Associated Herpesvirus Lytic Cycles by Short- and Medium-Chain Fatty Acids

    PubMed Central

    Gorres, Kelly L.; Daigle, Derek; Mohanram, Sudharshan

    2014-01-01

    ABSTRACT The lytic cycles of Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) are induced in cell culture by sodium butyrate (NaB), a short-chain fatty acid (SCFA) histone deacetylase (HDAC) inhibitor. Valproic acid (VPA), another SCFA and an HDAC inhibitor, induces the lytic cycle of KSHV but blocks EBV lytic reactivation. To explore the hypothesis that structural differences between NaB and VPA account for their functional effects on the two related viruses, we investigated the capacity of 16 structurally related short- and medium-chain fatty acids to promote or prevent lytic cycle reactivation. SCFAs differentially affected EBV and KSHV reactivation. KSHV was reactivated by all SCFAs that are HDAC inhibitors, including phenylbutyrate. However, several fatty acid HDAC inhibitors, such as isobutyrate and phenylbutyrate, did not reactivate EBV. Reactivation of KSHV lytic transcripts could not be blocked completely by any fatty acid tested. In contrast, several medium-chain fatty acids inhibited lytic activation of EBV. Fatty acids that blocked EBV reactivation were more lipophilic than those that activated EBV. VPA blocked activation of the BZLF1 promoter by NaB but did not block the transcriptional function of ZEBRA. VPA also blocked activation of the DNA damage response that accompanies EBV lytic cycle activation. Properties of SCFAs in addition to their effects on chromatin are likely to explain activation or repression of EBV. We concluded that fatty acids stimulate the two related human gammaherpesviruses to enter the lytic cycle through different pathways. IMPORTANCE Lytic reactivation of EBV and KSHV is needed for persistence of these viruses and plays a role in carcinogenesis. Our direct comparison highlights the mechanistic differences in lytic reactivation between related human oncogenic gammaherpesviruses. Our findings have therapeutic implications, as fatty acids are found in the diet and produced by the human microbiota. Small-molecule inducers of the lytic cycle are desired for oncolytic therapy. Inhibition of viral reactivation, alternatively, may prove useful in cancer treatment. Overall, our findings contribute to the understanding of pathways that control the latent-to-lytic switch and identify naturally occurring molecules that may regulate this process. PMID:24807711

  6. Microbial and functional diversity of a subterrestrial high pH groundwater associated to serpentinization.

    PubMed

    Tiago, Igor; Veríssimo, António

    2013-06-01

    Microbial and functional diversity were assessed, from a serpentinization-driven subterrestrial alkaline aquifer - Cabeço de Vide Aquifer (CVA) in Portugal. DGGE analyses revealed the presence of a stable microbial community. By 16S rRNA gene libraries and pyrosequencing analyses, a diverse bacterial composition was determined, contrasting with low archaeal diversity. Within Bacteria the majority of the populations were related to organisms or sequences affiliated to class Clostridia, but members of classes Acidobacteria, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Deinococci, Gammaproteobacteria and of the phyla Bacteroidetes, Chloroflexi and Nitrospira were also detected. Domain Archaea encompassed mainly sequences affiliated to Euryarchaeota. Only form I RuBisCO - cbbL was detected. Autotrophic carbon fixation via the rTCA, 3-HP and 3-HP/4H-B cycles could not be confirmed. The detected APS reductase alpha subunit - aprA sequences were phylogenetically related to sequences of sulfate-reducing bacteria belonging to Clostridia, and also to sequences of chemolithoautothrophic sulfur-oxidizing bacteria belonging to Betaproteobacteria. Sequences of methyl coenzyme M reductase - mcrA were phylogenetically affiliated to sequences belonging to Anaerobic Methanotroph group 1 (ANME-1). The populations found and the functional key markers detected in CVA suggest that metabolisms related to H2 , methane and/or sulfur may be the major driving forces in this environment. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  7. DIBROMOACETIC ACID-INDUCED ELEVATIONS OF ESTRADIOL IN THE CYCLING AND OVARIECTOMOZED/ESTRADIOL-IMPLANTED FEMALE RAT

    EPA Science Inventory

    Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations of Estradiol in Both Cycling and Ovariectomized / Estradiol-implanted Female Rats

    ABSTRACT
    Haloacetic acids are one of the principal classes of disinfection by-products generated by the chlorination of mun...

  8. Evolution of the enzymes of the citric acid cycle and the glyoxylate cycle of higher plants. A case study of endosymbiotic gene transfer.

    PubMed

    Schnarrenberger, Claus; Martin, William

    2002-02-01

    The citric acid or tricarboxylic acid cycle is a central element of higher-plant carbon metabolism which provides, among other things, electrons for oxidative phosphorylation in the inner mitochondrial membrane, intermediates for amino-acid biosynthesis, and oxaloacetate for gluconeogenesis from succinate derived from fatty acids via the glyoxylate cycle in glyoxysomes. The tricarboxylic acid cycle is a typical mitochondrial pathway and is widespread among alpha-proteobacteria, the group of eubacteria as defined under rRNA systematics from which mitochondria arose. Most of the enzymes of the tricarboxylic acid cycle are encoded in the nucleus in higher eukaryotes, and several have been previously shown to branch with their homologues from alpha-proteobacteria, indicating that the eukaryotic nuclear genes were acquired from the mitochondrial genome during the course of evolution. Here, we investigate the individual evolutionary histories of all of the enzymes of the tricarboxylic acid cycle and the glyoxylate cycle using protein maximum likelihood phylogenies, focusing on the evolutionary origin of the nuclear-encoded proteins in higher plants. The results indicate that about half of the proteins involved in this eukaryotic pathway are most similar to their alpha-proteobacterial homologues, whereas the remainder are most similar to eubacterial, but not specifically alpha-proteobacterial, homologues. A consideration of (a) the process of lateral gene transfer among free-living prokaryotes and (b) the mechanistics of endosymbiotic (symbiont-to-host) gene transfer reveals that it is unrealistic to expect all nuclear genes that were acquired from the alpha-proteobacterial ancestor of mitochondria to branch specifically with their homologues encoded in the genomes of contemporary alpha-proteobacteria. Rather, even if molecular phylogenetics were to work perfectly (which it does not), then some nuclear-encoded proteins that were acquired from the alpha-proteobacterial ancestor of mitochondria should, in phylogenetic trees, branch with homologues that are no longer found in most alpha-proteobacterial genomes, and some should reside on long branches that reveal affinity to eubacterial rather than archaebacterial homologues, but no particular affinity for any specific eubacterial donor.

  9. Impact of unusual fatty acid synthesis on futile cycling through beta-oxidation and on gene expression in transgenic plants.

    PubMed

    Moire, Laurence; Rezzonico, Enea; Goepfert, Simon; Poirier, Yves

    2004-01-01

    Arabidopsis expressing the castor bean (Ricinus communis) oleate 12-hydroxylase or the Crepis palaestina linoleate 12-epoxygenase in developing seeds typically accumulate low levels of ricinoleic acid and vernolic acid, respectively. We have examined the presence of a futile cycle of fatty acid degradation in developing seeds using the synthesis of polyhydroxyalkanoate (PHA) from the intermediates of the peroxisomal beta-oxidation cycle. Both the quantity and monomer composition of the PHA synthesized in transgenic plants expressing the 12-epoxygenase and 12-hydroxylase in developing seeds revealed the presence of a futile cycle of degradation of the corresponding unusual fatty acids, indicating a limitation in their stable integration into lipids. The expression profile of nearly 200 genes involved in fatty acid biosynthesis and degradation has been analyzed through microarray. No significant changes in gene expression have been detected as a consequence of the activity of the 12-epoxygenase or the 12-hydroxylase in developing siliques. Similar results have also been obtained for transgenic plants expressing the Cuphea lanceolata caproyl-acyl carrier protein thioesterase and accumulating high amounts of caproic acid. Only in developing siliques of the tag1 mutant, deficient in the accumulation of triacylglycerols and shown to have a substantial futile cycling of fatty acids toward beta-oxidation, have some changes in gene expression been detected, notably the induction of the isocitrate lyase gene. These results indicate that analysis of peroxisomal PHA is a better indicator of the flux of fatty acid through beta-oxidation than the expression profile of genes involved in lipid metabolism.

  10. Impact of Unusual Fatty Acid Synthesis on Futile Cycling through β-Oxidation and on Gene Expression in Transgenic Plants1[w

    PubMed Central

    Moire, Laurence; Rezzonico, Enea; Goepfert, Simon; Poirier, Yves

    2004-01-01

    Arabidopsis expressing the castor bean (Ricinus communis) oleate 12-hydroxylase or the Crepis palaestina linoleate 12-epoxygenase in developing seeds typically accumulate low levels of ricinoleic acid and vernolic acid, respectively. We have examined the presence of a futile cycle of fatty acid degradation in developing seeds using the synthesis of polyhydroxyalkanoate (PHA) from the intermediates of the peroxisomal β-oxidation cycle. Both the quantity and monomer composition of the PHA synthesized in transgenic plants expressing the 12-epoxygenase and 12-hydroxylase in developing seeds revealed the presence of a futile cycle of degradation of the corresponding unusual fatty acids, indicating a limitation in their stable integration into lipids. The expression profile of nearly 200 genes involved in fatty acid biosynthesis and degradation has been analyzed through microarray. No significant changes in gene expression have been detected as a consequence of the activity of the 12-epoxygenase or the 12-hydroxylase in developing siliques. Similar results have also been obtained for transgenic plants expressing the Cuphea lanceolata caproyl-acyl carrier protein thioesterase and accumulating high amounts of caproic acid. Only in developing siliques of the tag1 mutant, deficient in the accumulation of triacylglycerols and shown to have a substantial futile cycling of fatty acids toward β-oxidation, have some changes in gene expression been detected, notably the induction of the isocitrate lyase gene. These results indicate that analysis of peroxisomal PHA is a better indicator of the flux of fatty acid through β-oxidation than the expression profile of genes involved in lipid metabolism. PMID:14671017

  11. Biomedical research of novel biodegradable copoly(amino acid)s based on 6-aminocaproic acid and L-proline.

    PubMed

    Zhang, Weipeng; Shao, Jianmin

    2010-08-01

    The biomedical properties of novel biodegradable copoly(amino acid)s based on 6-aminocaproic acid and L-proline were analyzed in this article. The cytotoxicity of the copolymer films was tested in vitro using human embryonic kidney (HEK) 293 cells. The cell proliferation, cell cycle, cell apoptosis, and hemolysis of the polymers were also investigated. No significant cytotoxic response was detected statistically by cytotoxicity assay, and the results of cell apoptosis and cell cycle showed that there were no statistically significant differences in them. Generally, the cells spread and grew well on polymer film. Meanwhile, the extent of hemolysis on the polymers was acceptable. Evaluation of cytotoxicity by cell cycle and apoptosis as a supplementary assay is correspondingly discussed in this article. (c) 2010 Wiley Periodicals, Inc.

  12. Imbricatolic acid from Juniperus communis L. prevents cell cycle progression in CaLu-6 cells.

    PubMed

    De Marino, Simona; Cattaneo, Fabio; Festa, Carmen; Zollo, Franco; Iaccio, Annalisa; Ammendola, Rosario; Incollingo, Filomena; Iorizzi, Maria

    2011-11-01

    Imbricatolic acid was isolated from the methanolic extract of the fresh ripe berries of Juniperus communis (Cupressaceae) together with sixteen known compounds and a new dihydrobenzofuran lignan glycoside named juniperoside A. Their structures were determined by spectroscopic methods and by comparison with the spectral data reported in literature. Imbricatolic acid was evaluated for its ability to prevent cell cycle progression in p53-null CaLu-6 cells. This compound induces the upregulation of cyclin-dependent kinase inhibitors and their accumulation in the G1 phase of the cell cycle, as well as the degradation of cyclins A, D1, and E1. Furthermore, no significant imbricatolic acid-induced apoptosis was observed. Therefore, this plant-derived compound may play a role in the control of cell cycle. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Future Generation Tactical Engagement Simulation, U.S. Army Prioritized Needs and Recommended Supporting Technology Development. Volume 2

    DTIC Science & Technology

    1988-08-19

    SAW) f) anti-handling devices, g) Stinger, h) HEAT , i) MILES grenade (they can’t use training grenade in MOUT, j) MAX and MITS from LORAL for MOUT RTCA...work station by December 1986; will use NTC software which has been influenced by CMTC requirements. Evaluating Position Location (PL) systems for...they’ve been killed. Having problems with batteries due to both heat and cold; use up 5000 batteries a month. They need a simulator for a "bunker buster

  14. GPS Integrity Channel RTCA Working Group recommendations

    NASA Astrophysics Data System (ADS)

    Kalafus, Rudolph M.

    Recommendations made by a working group established by the Radio Technical Commission for Aeronautics are presented for the design of a wide-area broadcast service to provide indications on the status of GPS satellites. The integrity channel requirements and operational goals are outlined. Six integrity channel system concepts are considered and system design and time-to-alarm considerations are examined. The recommended system includes the broadcast of a coarse range measurement for each satellite which will enable the on-board GPS receiver to determine whether or not the navigation accuracy is within prescribed limits.

  15. Changes in sodium and uric acid concentrations in plasma during the menstrual cycle.

    PubMed

    Mira, M; Stewart, P M; Gebski, V; Llewellyn-Jones, D; Abraham, S F

    1984-03-01

    Hormonal changes during the menstrual cycle are well documented, but many other biochemical variables have not been studied. We find that in the luteal phase of the menstrual cycle the concentrations of sodium and uric acid are significantly lower. The changes may be of significance for the determination of the normal reference interval.

  16. Sulfuric acid on Europa and the radiolytic sulfur cycle.

    PubMed

    Carlson, R W; Johnson, R E; Anderson, M S

    1999-10-01

    A comparison of laboratory spectra with Galileo data indicates that hydrated sulfuric acid is present and is a major component of Europa's surface. In addition, this moon's visually dark surface material, which spatially correlates with the sulfuric acid concentration, is identified as radiolytically altered sulfur polymers. Radiolysis of the surface by magnetospheric plasma bombardment continuously cycles sulfur between three forms: sulfuric acid, sulfur dioxide, and sulfur polymers, with sulfuric acid being about 50 times as abundant as the other forms. Enhanced sulfuric acid concentrations are found in Europa's geologically young terrains, suggesting that low-temperature, liquid sulfuric acid may influence geological processes.

  17. Targeting MUC1-Mediated Tumor-Stromal Metabolic Interactions in Triple-Negative Breast Cancer

    DTIC Science & Technology

    2015-09-01

    exhibit increased dependence on glycolysis, resulting in abundant export of lactic acid . Lactic acid is mainly transported by two H+/lactate symporters...and ammonia recycling were most significantly altered in MDA-MB468 closely followed by citric acid cycle pathway. Mitochondrial electron transport...chain and citric acid cycle pathways were most significantly altered in BT20. Furthermore, relative comparison of the fold change in individual

  18. Stoichiometry of Reducing Equivalents and Splitting of Water in the Citric Acid Cycle.

    ERIC Educational Resources Information Center

    Madeira, Vitor M. C.

    1988-01-01

    Presents a solution to the problem of finding the source of extra reducing equivalents, and accomplishing the stoichiometry of glucose oxidation reactions. Discusses the citric acid cycle and glycolysis. (CW)

  19. Alternative carbohydrate reserves used in the daily cycle of crassulacean acid metabolism

    Treesearch

    C.C. Black; J.-Q. Chen; R.L. Doong; M.N. Angelov; Shi-Jean S. Sung

    1996-01-01

    Each day a massive interlocked biochemical cycle occurs in the green tissues of crassulacean acid metabolism plants.The function of this interlocked cycle, in its simplest context, is to furnish most of the CO2 for CAM plant photosynthesis.In this unified presentation our aims are (1) to divide CAM plants into two metabolic groups, (2) to...

  20. Ecotypic variability in the metabolic response of seeds to diurnal hydration-dehydration cycles and its relationship to seed vigor.

    PubMed

    Bai, Bing; Sikron, Noga; Gendler, Tanya; Kazachkova, Yana; Barak, Simon; Grafi, Gideon; Khozin-Goldberg, Inna; Fait, Aaron

    2012-01-01

    Seeds in the seed bank experience diurnal cycles of imbibition followed by complete dehydration. These conditions pose a challenge to the regulation of germination. The effect of recurring hydration-dehydration (Hy-Dh) cycles were tested on seeds from four Arabidopsis thaliana accessions [Col-0, Cvi, C24 and Ler]. Diurnal Hy-Dh cycles had a detrimental effect on the germination rate and on the final percentage of germination in Col-0, Cvi and C24 ecotypes, but not in the Ler ecotype, which showed improved vigor following the treatments. Membrane permeability measured by ion conductivity was generally increased following each Hy-Dh cycle and was correlated with changes in the redox status represented by the GSSG/GSH (oxidized/reduced glutathione) ratio. Among the ecotypes, Col-0 seeds displayed the highest membrane permeability, whilst Ler was characterized by the greatest increase in electrical conductivity following Hy-Dh cycles. Following Dh 2 and Dh 3, the respiratory activity of Ler seeds significantly increased, in contrast to the other ecotypes, indicative of a dramatic shift in metabolism. These differences were associated with accession-specific content and patterns of change of (i) cell wall-related laminaribiose and mannose; (ii) fatty acid composition, specifically of the unsaturated oleic acid and α-linoleic acid; and (iii) asparagine, ornithine and the related polyamine putrescine. Furthermore, in the Ler ecotype the content of the tricarboxylic acid (TCA) cycle intermediates fumarate, succinate and malate increased in response to dehydration, in contrast to a decrease in the other three ecotypes. These findings provide a link between seed respiration, energy metabolism, fatty acid β-oxidation, nitrogen mobilization and membrane permeability and the improved germination of Ler seeds following Hy-Dh cycles.

  1. Modulation of chondrocyte motility by tetrahedral DNA nanostructures.

    PubMed

    Shi, Sirong; Lin, Shiyu; Shao, Xiaoru; Li, Qianshun; Tao, Zhang; Lin, Yunfeng

    2017-10-01

    Contemporarily, a highly increasing attention was paid to nanoconstructs, particularly DNA nanostructures possessing precise organization, functional manipulation, biocompatibility and biodegradability. Amongst these DNA nanomaterials, tetrahedral DNA nanostructures (TDNs) are a significantly ideal bionanomaterials with focusing on the property that can be internalized into cytoplasm in the absence of transfection. Therefore, the focus of this study was on investigating the influence of TDNs on the chondrocytes locomotion. Tetrahedral DNA nanostructures was confirmed by 6% polyacrylamide gel electrophoresis (PAGE) and dynamic light scattering (DLS). Subsequently, the effect of TDNs on chondrocyte locomotion was investigated by real-time cell analysis (RTCA) and wound healing assay. The variation of relevant genes and proteins was detected by quantitative polymerase chain reaction (qPCR), western blotting and immunofluorescence respectively. We demonstrated that tetrahedral DNA nanostructures have positive influence on chondrocytes locomotion and promoted the expression of RhoA, ROCK2 and vinculin. Additionally, upon exposure to TDNs with the concentration of 250 nmol L -1 , the chondrocytes were showed the highest motility via both RTCA and wound healing assay. Meanwhile, the mRNA and protein expression of RhoA, ROCK2 and vinculin were also significantly enhanced with the same concentration. It can be concluded that the TDNs with the optimal concentration of 250 nmol L -1 could extremely promoted the chondrocytes locomotion through facilitating the expression of RhoA, ROCK2 and vinculin. These results seemed to reveal that this special three-dimensional DNA tetrahedral nanostructures may be applied to cartilage repair and treatment in the future. © 2017 John Wiley & Sons Ltd.

  2. The Path of Carbon in Photosynthesis VIII. The Role of Malic Acid

    DOE R&D Accomplishments Database

    Bassham, James A.; Benson, Andrew A.; Calvin, Melvin

    1950-01-25

    Malonate has been found to inhibit the formation of malic acid during short periods of photosynthesis with radioactive carbon dioxide. This result, together with studies which show the photosynthetic cycle to be operating normally at the same time, indicates that malic acid is not an intermediate in photosynthesis but is probably closely related to some intermediate of the cycle. Absence of labeled succinic and fumaric acids in these experiments, in addition to the failure of malonate to inhibit photosynthesis, precludes the participation of these acids as intermediates in photosynthesis.

  3. Methylcitrate cycle defines the bactericidal essentiality of isocitrate lyase for survival of Mycobacterium tuberculosis on fatty acids

    PubMed Central

    Eoh, Hyungjin; Rhee, Kyu Y.

    2014-01-01

    Few mutations attenuate Mycobacterium tuberculosis (Mtb) more profoundly than deletion of its isocitrate lyases (ICLs). However, the basis for this attenuation remains incompletely defined. Mtb’s ICLs are catalytically bifunctional isocitrate and methylisocitrate lyases required for growth on even and odd chain fatty acids. Here, we report that Mtb’s ICLs are essential for survival on both acetate and propionate because of its methylisocitrate lyase (MCL) activity. Lack of MCL activity converts Mtb’s methylcitrate cycle into a “dead end” pathway that sequesters tricarboxylic acid (TCA) cycle intermediates into methylcitrate cycle intermediates, depletes gluconeogenic precursors, and results in defects of membrane potential and intrabacterial pH. Activation of an alternative vitamin B12-dependent pathway of propionate metabolism led to selective corrections of TCA cycle activity, membrane potential, and intrabacterial pH that specifically restored survival, but not growth, of ICL-deficient Mtb metabolizing acetate or propionate. These results thus resolve the biochemical basis of essentiality for Mtb’s ICLs and survival on fatty acids. PMID:24639517

  4. Comparative study of toxicological and cell cycle effects of okadaic acid and dinophysistoxin-2 in primary rat hepatocytes.

    PubMed

    Rubiolo, J A; López-Alonso, H; Vega, F V; Vieytes, M R; Botana, L M

    2012-03-10

    To determine the relative toxicity and effects on the cell cycle of okadaic acid and dinophysistoxin-2 in primary hepatocyte cultures. Cytotoxicity was determined by the MTT method, caspase-3 activity and lactate dehydrogenase release to the medium. The cell cycle analysis was performed by imaging flow cytometry and the effect of the toxins on cell proliferation was studied by quantitative PCR and confocal microscopy. We show that dinophysistoxin-2 is less toxic than okadaic acid for primary hepatocytes with a similar difference in potency as that observed in vivo in mice after intraperitoneal injection. Both toxins induced apoptosis with caspase-3 increase. They also inhibited the hepatocytes cell cycle in G1 affecting diploid cells and diploid bi-nucleated cells. In proliferating hepatocytes exposed to the toxins, a decrease of p53 gene expression as well as a lower protein level was detected. Studies of the tubulin cytoskeleton in toxin treated cells, showed nuclear localization of this molecule and a granulated tubulin pattern in the cytoplasm. The results presented in this work show that the difference in toxicity between dinophysistoxin-2 and okadaic acid in cultured primary hepatocytes is the same as that observed in vivo after intraperitoneal injection. Okadaic acid and dinophysistoxin-2 arrest the cell cycle of hepatocytes at G1 even in diploid bi-nucleated cells. p53 and tubulin could be involved in the cell cycle inhibitory effect. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Serum Amino Acid Profiling in Citrin-Deficient Children Exhibiting Normal Liver Function During the Apparently Healthy Period.

    PubMed

    Miyazaki, Teruo; Nagasaka, Hironori; Komatsu, Haruki; Inui, Ayano; Morioka, Ichiro; Tsukahara, Hirokazu; Kaji, Shunsaku; Hirayama, Satoshi; Miida, Takashi; Kondou, Hiroki; Ihara, Kenji; Yagi, Mariko; Kizaki, Zenro; Bessho, Kazuhiko; Kodama, Takahiro; Iijima, Kazumoto; Yorifuji, Tohru; Matsuzaki, Yasushi; Honda, Akira

    2018-04-14

    Citrin (mitochondrial aspartate-glutamate transporter) deficiency causes the failures in both carbohydrate-energy metabolism and the urea cycle, and the alterations in the serum levels of several amino acids in the stages of newborn (NICCD) and adult (CTLN2). However, the clinical manifestations are resolved between the NICCD and CTLN2, but the reasons are still unclear. This study evaluated the serum amino acid profile in citrin-deficient children during the healthy stage. Using HPLC-MS/MS analysis, serum amino acids were evaluated among 20 citrin-deficient children aged 5-13 years exhibiting normal liver function and 35 age-matched healthy controls. The alterations in serum amino acids characterized in the NICCD and CTLN2 stages were not observed in the citrin-deficient children. Amino acids involved in the urea cycle, including arginine, ornithine, citrulline, and aspartate, were comparable in the citrin-deficient children to the respective control levels, but serum urea was twofold higher, suggestive of a functional urea cycle. The blood sugar level was normal, but glucogenic amino acids and glutamine were significantly decreased in the citrin-deficient children compared to those in the controls. In addition, significant increases of ketogenic amino acids, branched-chain amino acids (BCAAs), a valine intermediate 3-hydroxyisobutyrate, and β-alanine were also found in the citrin-deficient children. The profile of serum amino acids in the citrin-deficient children during the healthy stage showed different characteristics from the NICCD and CTLN2 stages, suggesting that the failures in both urea cycle function and energy metabolism might be compensated by amino acid metabolism. In the citrin-deficient children during the healthy stage, the characteristics of serum amino acids, including decrease of glucogenic amino acids, and increase of ketogenic amino acids, BCAAs, valine intermediate, and β-alanine, were found by comparison to the age-matched healthy control children, and it suggested that the characteristic alteration of serum amino acids may be resulted from compensation for energy metabolism and ammonia detoxification.

  6. Retinoic acid downregulates Rae1 leading to APC(Cdh1) activation and neuroblastoma SH-SY5Y differentiation.

    PubMed

    Cuende, J; Moreno, S; Bolaños, J P; Almeida, A

    2008-05-22

    In neuroblastoma cells, retinoic acid induces cell cycle arrest and differentiation through degradation of the F-box protein, Skp2, and stabilization of cyclin-dependent kinase inhibitor, p27. However, the mechanism responsible for retinoic acid-mediated Skp2 destabilization is unknown. Since Skp2 is degraded by anaphase-promoting complex (APC)(Cdh1), here we studied whether retinoic acid promotes differentiation of human SH-SY5Y neuroblastoma cells by modulating Cdh1. We found that retinoic acid induced the nuclear accumulation of Cdh1 that paralleled Skp2 destabilization and p27 accumulation. The mRNA and protein abundance of Rae1-a nuclear export factor that limits APC(Cdh1) activity in mitosis-decreased upon retinoic acid-induced inhibition of neuroblastoma cell proliferation. Furthermore, either Rae1 overexpression or Cdh1 inhibition promoted Skp2 accumulation, p27 destabilization and prevented retinoic acid-induced cell cycle arrest and differentiation. Conversely, inhibition of Rae1 accelerated retinoic acid-induced differentiation. Thus, retinoic acid downregulates Rae1, hence facilitating APC(Cdh1)-mediated Skp2 degradation leading to the arrest of cell cycle progression and neuroblastoma differentiation.

  7. Effect of alternative pathway therapy on branched chain amino acid metabolism in urea cycle disorder patients.

    PubMed

    Scaglia, Fernando; Carter, Susan; O'Brien, William E; Lee, Brendan

    2004-04-01

    Urea cycle disorders (UCDs) are a group of inborn errors of hepatic metabolism caused by the loss of enzymatic activities that mediate the transfer of nitrogen from ammonia to urea. These disorders often result in life-threatening hyperammonemia and hyperglutaminemia. A combination of sodium phenylbutyrate and sodium phenylacetate/benzoate is used in the clinical management of children with urea cycle defects as a glutamine trap, diverting nitrogen from urea synthesis to alternatives routes of excretion. We have observed that patients treated with these compounds have selective branched chain amino acid (BCAA) deficiency despite adequate dietary protein intake. However, the direct effect of alternative therapy on the steady state levels of plasma branched chain amino acids has not been well characterized. We have measured steady state plasma branched chain and other essential non-branched chain amino acids in control subjects, untreated ornithine transcarbamylase deficiency females and treated null activity urea cycle disorder patients in the fed steady state during the course of stable isotope studies. Steady-state leucine levels were noted to be significantly lower in treated urea cycle disorder patients when compared to either untreated ornithine transcarbamylase deficiency females or control subjects (P<0.0001). This effect was reproduced in control subjects who had depressed leucine levels when treated with sodium phenylacetate/benzoate (P<0.0001). Our studies suggest that this therapeutic modality has a substantial impact on the metabolism of branched chain amino acids in urea cycle disorder patients. These findings suggest that better titration of protein restriction could be achieved with branched chain amino acid supplementation in patients with UCDs who are on alternative route therapy.

  8. Menstrual cycle characteristics as determinants of plasma concentrations of perfluoroalkyl substances (PFASs) in the Norwegian Mother and Child Cohort (MoBa study).

    PubMed

    Singer, Alison B; Whitworth, Kristina W; Haug, Line S; Sabaredzovic, Azemira; Impinen, Antti; Papadopoulou, Eleni; Longnecker, Matthew P

    2018-06-04

    Perfluoroalkyl substances (PFASs) are fluorinated organic compounds that have been used in a variety of industrial and consumer applications. Menstruation is implicated as a possible route of elimination for PFASs in women. The overall purpose of this study was to examine menstrual cycle characteristics as determinants of plasma PFAS concentrations in women. Our study sample consisted of 1977 pregnant women from the Norwegian Mother and Child Cohort (MoBa) study. The women were asked about menstrual cycle regularity in the year before the pregnancy and typical menstrual cycle length as well as other demographic and reproductive characteristics in a questionnaire completed during the pregnancy. Blood samples were collected around 17-18 weeks gestation and PFAS concentrations were measured in plasma. We examined the association between menstrual cycle characteristics and seven PFASs (perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS), and perfluorooctane sulfonate (PFOS)) using multiple linear regression, adjusted for age, pre-pregnancy body mass index, smoking, education, income, parity, oral contraceptive use, inter-pregnancy interval, and breastfeeding duration. Irregular cycles were not associated with PFAS concentrations. Overall, we found no evidence of associations between menstrual cycle length and PFAS concentrations. In subgroup analyses we found some evidence, among parous women, of decreased PFHpS and PFOS with short menstrual cycles; we also found, among recent OC users (in the 12 months before the questionnaire) increased PFNA and PFUnDA with long cycle length. Limitations of our study include misclassification of menstrual cycle characteristics, small sample sizes in the sub-group analyses, and a lack of information on duration and volume of menses. In the entire study sample, we found little evidence of menstrual cycle characteristics as determinants of PFAS concentrations. However, we observed some associations between cycle length and PFAS concentrations with some select PFAS compounds in subgroup analyses. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Chopper-controlled discharge life cycling studies on lead-acid batteries

    NASA Technical Reports Server (NTRS)

    Kraml, J. J.; Ames, E. P.

    1982-01-01

    State-of-the-art 6 volt lead-acid golf car batteries were tested. A daily charge/discharge cycling to failure points under various chopper controlled pulsed dc and continuous current load conditions was undertaken. The cycle life and failure modes were investigated for depth of discharge, average current chopper frequency, and chopper duty cycle. It is shown that battery life is primarily and inversely related to depth of discharge and discharge current. Failure mode is characterized by a gradual capacity loss with consistent evidence of cell element aging.

  10. SURFACE DEGRADATION OF COMPOSITE RESINS BY ACIDIC MEDICINES AND pH-CYCLING

    PubMed Central

    Valinoti, Ana Carolina; Neves, Beatriz Gonçalves; da Silva, Eduardo Moreira; Maia, Lucianne Cople

    2008-01-01

    This study evaluated the effects of acidic medicines (Dimetapp® and Claritin®), under pH-cycling conditions, on the surface degradation of four composite resins (microhybrid: TPH, Concept, Opallis and Nanofilled: Supreme). Thirty disc-shaped specimens (Ø = 5.0 mm / thickness = 2.0 mm) of each composite were randomly assigned to 3 groups (n = 10): a control and two experimental groups, according to the acidic medicines evaluated. The specimens were finished and polished with aluminum oxide discs, and the surface roughness was measured by using a profilometer. After the specimens were submitted to a pH-cycling regimen and immersion in acidic medicines for 12 days, the surface roughness was measured again. Two specimens for each material and group were analyzed by scanning electron microscopy (SEM) before and after pH-cycling. Data were analyzed by the Student's-t test, ANOVA, Duncan's multiple range test and paired t-test (α=0.05). Significant increase in roughness was found only for TPH in the control group and TPH and Supreme immersed in Claritin® (p<0.05). SEM analyses showed that the 4 composite resins underwent erosion and surface degradation after being subjected to the experimental conditions. In conclusion, although the roughness was slightly affected, the pH-cycling and acidic medicines caused surface degradation of the composite resins evaluated. Titratable acidity seemed to play a more crucial role on surface degradation of composite resins than pH. PMID:19089257

  11. Self-organizing biochemical cycles

    NASA Technical Reports Server (NTRS)

    Orgel, L. E.; Bada, J. L. (Principal Investigator)

    2000-01-01

    I examine the plausibility of theories that postulate the development of complex chemical organization without requiring the replication of genetic polymers such as RNA. One conclusion is that theories that involve the organization of complex, small-molecule metabolic cycles such as the reductive citric acid cycle on mineral surfaces make unreasonable assumptions about the catalytic properties of minerals and the ability of minerals to organize sequences of disparate reactions. Another conclusion is that data in the Beilstein Handbook of Organic Chemistry that have been claimed to support the hypothesis that the reductive citric acid cycle originated as a self-organized cycle can more plausibly be interpreted in a different way.

  12. UAS Integration into the NAS: Detect and Avoid Display Evaluations in Support of SC-228 MOPS Development

    NASA Technical Reports Server (NTRS)

    Fern, Lisa; Rorie, Conrad; Shively, Jay

    2015-01-01

    This presentation provides an overview of the work the Human Systems Integration (HSI) sub-project has done on detect and avoid (DAA) displays while working on the UAS Integration into the NAS project. Much of the work has been used to support the ongoing development of minimum operational performance standards (MOPS) for UAS by RTCA Special Committee 228. The design and results of three different human-in-the-loop simulations are discussed, with particular emphasis on the role of the UAS pilot in the Self Separation Timeline.

  13. NASA UAS Integration into the NAS Project Detect and Avoid Display Evaluations

    NASA Technical Reports Server (NTRS)

    Shively, Jay

    2016-01-01

    As part of the Air Force - NASA Bi-Annual Research Council Meeting, slides will be presented on phase 1 Detect and Avoid (DAA) display evaluations. A series of iterative human-in-the-loops (HITL) experiments were conducted with different display configurations to objectively measure pilot performance on maintaining well clear. To date, four simulations and two mini-HITLs have been conducted. Data from these experiments have been incorporated into a revised alerting structure and included in the RTCA SC 228 Phase 1 Minimum Operational Performance Standards (MOPS) proposal. Plans for phase 2 are briefly discussed.

  14. Guidance for Using Formal Methods in a Certification Context

    NASA Technical Reports Server (NTRS)

    Brown, Duncan; Delseny, Herve; Hayhurst, Kelly; Wiels, Virginie

    2010-01-01

    This paper discusses some of the challenges to using formal methods in a certification context and describes the effort by the Formal Methods Subgroup of RTCA SC-205/EUROCAE WG-71 to propose guidance to make the use of formal methods a recognized approach. This guidance, expected to take the form of a Formal Methods Technical Supplement to DO-178C/ED-12C, is described, including the activities that are needed when using formal methods, new or modified objectives with respect to the core DO-178C/ED-12C document, and evidence needed for meeting those objectives.

  15. UAS Modeling of the Communication Links Study Results

    NASA Technical Reports Server (NTRS)

    Birr, Richard B.; Girgis, Nancy; Murray, Jennifer

    2011-01-01

    The Federal Aviation Administration (FAA) is the authority that grants access into, and operations within, the National Airspace System (NAS) for all aircraft, including Unmanned Aircraft Systems (UAS). The safe operation of UAS in the NAS must be assured if the full potential of UAS is to be realized and supported by the public and Congress. This report analyzed the communication systems that are needed for the safe operations of UAS in the NAS. Safe operations can be defined as the availability of the required links to carry the information to control the UAS and the return links to allow controllers to know where the UAS is at any given moment as well as how it is performing. This report is the end result of work performed jointly between the FAA and National Aeronautics and Space Administration (NASA)/Kennedy Space Center (NASA KSC). The work was done in support of the Radio Technical Commission for Aeronautics (RTCA) Special Committee 203 (SC-203) Control and Communications Working Group. The RTCA is a federal advisory committee to the FAA. Though the work was not under the direction of the working group, a large part of the specific values used in the simulations came from the working group. Specifically, all of the radio links were modeled based on the formulation completed by the working group. This report analyzed three scenarios from RTCA SC-203 that represent how a UAS would operate in the NAS. Each scenario was created using the Satellite Tool Kit (STK) modeling and simulation tool. The flight paths of the UAS were generated and the UAS dynamics were likewise modeled. Then each communication asset such as transmitters, receivers, and antennas were modeled and placed on the appropriate UAS, satellite, or Control Station (CS). After that, the radio links were analyzed for signal strength and antenna blockage, and the overall link performance was analyzed in detail. The goal was to obtain 99.9% availability on all of the radio communication links. In order to ensure the 99.9% availability, certain values for the telemetry transmitter will have to be increased slightly from I watt up to about 4 watts which is reasonable. The results of this analysis show that it is possible to send commands, during the airborne segment, to the Unmanned Aircraft (UA) and have the UA send back the system health and status with high availability of at least 99.9% of the time. This 99.9% availability included the condition of heavy rain at 90 mm/hr as well as interference from adjacent satellites. The link budget values used in this report were based on the work from the working group.

  16. Guidance and Control Software Project Data - Volume 2: Development Documents

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J. (Editor)

    2008-01-01

    The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the development documents from the GCS project. Volume 2 contains three appendices: A. Guidance and Control Software Development Specification; B. Design Description for the Pluto Implementation of the Guidance and Control Software; and C. Source Code for the Pluto Implementation of the Guidance and Control Software

  17. New evidence for antioxidant properties of vitamin C.

    PubMed

    Vojdani, A; Bazargan, M; Vojdani, E; Wright, J

    2000-01-01

    This study was designed to examine the effect of 500 to 5,000 mg of ascorbic acid on DNA adducts, natural killer (NK) cell activity, programmed cell death, and cell cycle analysis of human peripheral blood leukocytes. According to our hypothesis, if ascorbic acid is a pro-oxidant, doses between 500 and 5,000 mg should enhance DNA adduct formation, decrease immune function, change the cell cycle progression, and increase the rate of apoptosis. Twenty healthy volunteers were divided into four groups and given either placebo or daily doses of 500, 1,000 or 5,000 mg of ascorbic acid for a period of 2 weeks. On days 0, 1, 7, 15, and 21, blood was drawn from them, and the leukocytes were separated and examined for intracellular levels of ascorbic acid, the level of 8-hydroxyguanosine, NK cell activity, cell cycle progression, and apoptosis. Depending on the subjects, between a 0% and a 40% increase in cellular absorption of ascorbic acid was observed when daily doses of 500 mg were used. At doses greater than 500 mg, this cellular absorption was not increased further, and all doses produced equivalent increases in ascorbic acid on days 1 to 15. This increase in cellular concentration of ascorbic acid resulted in no statistically meaningful changes in the level of 8-hydroxyguanosine, increased NK cytotoxic activity, a reduced percentage of cells undergoing apoptosis, and switched cell cycle phases from S and G2/M to G0/G1. After a period of 1 week, with no placebo or vitamin washout, ascorbic acid levels along with functional assays returned to the baseline and became equivalent to placebos. In comparison with baseline values, no change (not more than daily assays variation) was seen in ascorbate concentrations or other assays during oral placebo treatment. We concluded that ascorbic acid is an antioxidant and that doses up to 5,000 mg neither induce mutagenic lesions nor have negative effects on NK cell activity, apoptosis, or cell cycle.

  18. Citric acid induces cell-cycle arrest and apoptosis of human immortalized keratinocyte cell line (HaCaT) via caspase- and mitochondrial-dependent signaling pathways.

    PubMed

    Ying, Tsung-Ho; Chen, Chia-Wei; Hsiao, Yu-Ping; Hung, Sung-Jen; Chung, Jing-Gung; Yang, Jen-Hung

    2013-10-01

    Citric acid is an alpha-hydroxyacid (AHA) widely used in cosmetic dermatology and skincare products. However, there is concern regarding its safety for the skin. In this study, we investigated the cytotoxic effects of citric acid on the human keratinocyte cell line HaCaT. HaCaT cells were treated with citric acid at 2.5-12.5 mM for different time periods. Cell-cycle arrest and apoptosis were investigated by 4,6-diamidino-2-phenylindole dihydrochloride (DAPI) staining, flow cytometry, western blot and confocal microscopy. Citric acid not only inhibited proliferation of HaCaT cells in a dose-dependent manner, but also induced apoptosis and cell cycle-arrest at the G2/M phase (before 24 h) and S phase (after 24 h). Citric acid increased the level of Bcl-2-associated X protein (BAX) and reduced the levels of B-cell lymphoma-2 (BCL-2), B-cell lymphoma-extra large (BCL-XL) and activated caspase-9 and caspase-3, which subsequently induced apoptosis via caspase-dependent and caspase-independent pathways. Citric acid also activated death receptors and increased the levels of caspase-8, activated BH3 interacting-domain death agonist (BID) protein, Apoptosis-inducing factor (AIF), and Endonuclease G (EndoG). Therefore, citric acid induces apoptosis through the mitochondrial pathway in the human keratinocyte cell line HaCaT. The study results suggest that citric acid is cytotoxic to HaCaT cells via induction of apoptosis and cell-cycle arrest in vitro.

  19. Organic Acids: The Pools of Fixed Carbon Involved in Redox Regulation and Energy Balance in Higher Plants

    PubMed Central

    Igamberdiev, Abir U.; Eprintsev, Alexander T.

    2016-01-01

    Organic acids are synthesized in plants as a result of the incomplete oxidation of photosynthetic products and represent the stored pools of fixed carbon accumulated due to different transient times of conversion of carbon compounds in metabolic pathways. When redox level in the cell increases, e.g., in conditions of active photosynthesis, the tricarboxylic acid (TCA) cycle in mitochondria is transformed to a partial cycle supplying citrate for the synthesis of 2-oxoglutarate and glutamate (citrate valve), while malate is accumulated and participates in the redox balance in different cell compartments (via malate valve). This results in malate and citrate frequently being the most accumulated acids in plants. However, the intensity of reactions linked to the conversion of these compounds can cause preferential accumulation of other organic acids, e.g., fumarate or isocitrate, in higher concentrations than malate and citrate. The secondary reactions, associated with the central metabolic pathways, in particularly with the TCA cycle, result in accumulation of other organic acids that are derived from the intermediates of the cycle. They form the additional pools of fixed carbon and stabilize the TCA cycle. Trans-aconitate is formed from citrate or cis-aconitate, accumulation of hydroxycitrate can be linked to metabolism of 2-oxoglutarate, while 4-hydroxy-2-oxoglutarate can be formed from pyruvate and glyoxylate. Glyoxylate, a product of either glycolate oxidase or isocitrate lyase, can be converted to oxalate. Malonate is accumulated at high concentrations in legume plants. Organic acids play a role in plants in providing redox equilibrium, supporting ionic gradients on membranes, and acidification of the extracellular medium. PMID:27471516

  20. DIBROMOACETIC ACID-INDUCED ELEVATIONS IN CIRCULATING ESTRADIOL: EFFECTS IN BOTH CYCLING AND OVARIECTOMIZED/STEROID-PRIMED FEMALE RATS

    EPA Science Inventory

    RTD-03-031
    Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations in Circulating Estradiol: Effects in Both Cycling and Ovariectomized/Steroid-primed Female Rats. Reproductive Toxicology (in press).

    Abstract

    Oral exposures to high concentrations of th...

  1. Duty cycle dependent chemical structure and wettability of RF pulsed plasma copolymers of acrylic acid and octafluorocyclobutane

    NASA Astrophysics Data System (ADS)

    Muzammil, I.; Li, Y. P.; Li, X. Y.; Lei, M. K.

    2018-04-01

    Octafluorocyclobutane and acrylic acid (C4F8-co-AA) plasma copolymer coatings are deposited using a pulsed wave (PW) radio frequency (RF) plasma on low density polyethylene (LDPE). The influence of duty cycle in pulsed process with the monomer feed rate on the surface chemistry and wettability of C4F8-co-AA plasma polymer coatings is studied. The concentration of the carboxylic acid (hydrophilic) groups increase, and that of fluorocarbon (hydrophobic) groups decrease by lowering the duty cycle. The combined effect of surface chemistry and surface morphology of the RF pulsed plasma copolymer coatings causes tunable surface wettability and surface adhesion. The gradual emergence of hydrophilic contents leads to surface heterogeneity by lowering duty cycle causing an increased surface adhesion in hydrophobic coatings. The C4F8-co-AA plasma polymer coatings on the nanotextured surfaces are tuned from repulsive superhydrophobicity to adhesive superhydrophobicity, and further to superhydrophilicity by adjusting the duty cycles with the monomer feed rates.

  2. Serum metabolic changes in rats after intragastric administration of dextromethorphan.

    PubMed

    Bao, Shihui; Zhang, Jing; Lin, Zixia; Su, Ke; Mo, Jingjing; Hong, Lin; Qian, Shuyi; Chen, Lianguo; Sun, Fa; Wen, Congcong; Wu, Qing; Hu, Lufeng; Lin, Guanyang; Wang, Xianqin

    2017-03-01

    Dextromethorphan is recognized as a substance of abuse around the world. An estimated 3.1 million people between the ages of 12 and 25 years (5.3%) misused over-the-counter cough and cold medications in 2006. In this study, we developed a serum metabolomic method by gas chromatography-mass spectrometry (GC-MS) to evaluate the effect of abuse of dextromethorphan on rats. The dextromethorphan-treated rats were given 12, 24 and 48 mg/kg (low, medium, high) of dextromethorphan by intragastric administration each day for 3 days. Partial least squares-discriminate analysis revealed that intragastric administration of dextromethorphan induced metabolic perturbations. Compared with the control (healthy) group, the levels of propanoic acid, urea, heptafluorobutanoic acid, 2-hexyldecanoic acid and butanedioic acid of the low group decreased; levels of propanoic acid and heptafluorobutanoic acid of the medium group decreased, while that of benzoic acid increased; and levels of 2-hexyldecanoic acid, glycerol and butanedioic acid of the high group increased. These biomarkers are involved in the citric acid cycle, urea cycle, glycerolipid metabolism and tricarboxylic acid cycle. The results indicate that the metabolomic method by GC-MS may be useful to elucidate abuse of dextromethorphan. According to the pathological changes in the liver at different dosages, dextromethorphan is not hepatotoxic after intragastric administration of 12, 24 and 48 mg/kg for 3 days. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Halogenated methanesulfonic acids: A new class of organic micropollutants in the water cycle.

    PubMed

    Zahn, Daniel; Frömel, Tobias; Knepper, Thomas P

    2016-09-15

    Mobile and persistent organic micropollutants may impact raw and drinking waters and are thus of concern for human health. To identify such possible substances of concern nineteen water samples from five European countries (France, Switzerland, The Netherlands, Spain and Germany) and different compartments of the water cycle (urban effluent, surface water, ground water and drinking water) were enriched with mixed-mode solid phase extraction. Hydrophilic interaction liquid chromatography - high resolution mass spectrometry non-target screening of these samples led to the detection and structural elucidation of seven novel organic micropollutants. One structure could already be confirmed by a reference standard (trifluoromethanesulfonic acid) and six were tentatively identified based on experimental evidence (chloromethanesulfonic acid, dichloromethanesulfonic acid, trichloromethanesulfonic acid, bromomethanesulfonic acid, dibromomethanesulfonic acid and bromochloromethanesulfonic acid). Approximated concentrations for these substances show that trifluoromethanesulfonic acid, a chemical registered under the European Union regulation REACH with a production volume of more than 100 t/a, is able to spread along the water cycle and may be present in concentrations up to the μg/L range. Chlorinated and brominated methanesulfonic acids were predominantly detected together which indicates a common source and first experimental evidence points towards water disinfection as a potential origin. Halogenated methanesulfonic acids were detected in drinking waters and thus may be new substances of concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Effect of ellagic acid on proliferation, cell adhesion and apoptosis in SH-SY5Y human neuroblastoma cells.

    PubMed

    Fjaeraa, Christina; Nånberg, Eewa

    2009-05-01

    Ellagic acid, a polyphenolic compound found in berries, fruits and nuts, has been shown to possess growth-inhibiting and apoptosis promoting activities in cancer cell lines in vitro. The objective of this study was to investigate the effect of ellagic acid in human neuroblastoma SH-SY5Y cells. In cultures of SH-SY5Y cells incubated with ellagic acid, time- and concentration-dependent inhibitory effects on cell number were demonstrated. Ellagic acid induced cell detachment, decreased cell viability and induced apoptosis as measured by DNA strand breaks. Ellagic acid-induced alterations in cell cycle were also observed. Simultaneous treatment with all-trans retinoic acid did not rescue the cells from ellagic acid effects. Furthermore, the results suggested that pre-treatment with all-trans retinoic acid to induce differentiation and cell cycle arrest did not rescue the cells from ellagic acid-induced cell death.

  5. The use of real-time cell analyzer technology in drug discovery: defining optimal cell culture conditions and assay reproducibility with different adherent cellular models.

    PubMed

    Atienzar, Franck A; Tilmant, Karen; Gerets, Helga H; Toussaint, Gaelle; Speeckaert, Sebastien; Hanon, Etienne; Depelchin, Olympe; Dhalluin, Stephane

    2011-07-01

    The use of impedance-based label-free technology applied to drug discovery is nowadays receiving more and more attention. Indeed, such a simple and noninvasive assay that interferes minimally with cell morphology and function allows one to perform kinetic measurements and to obtain information on proliferation, migration, cytotoxicity, and receptor-mediated signaling. The objective of the study was to further assess the usefulness of a real-time cell analyzer (RTCA) platform based on impedance in the context of quality control and data reproducibility. The data indicate that this technology is useful to determine the best coating and cellular density conditions for different adherent cellular models including hepatocytes, cardiomyocytes, fibroblasts, and hybrid neuroblastoma/neuronal cells. Based on 31 independent experiments, the reproducibility of cell index data generated from HepG2 cells exposed to DMSO and to Triton X-100 was satisfactory, with a coefficient of variation close to 10%. Cell index data were also well reproduced when cardiomyocytes and fibroblasts were exposed to 21 compounds three times (correlation >0.91, p < 0.0001). The data also show that a cell index decrease is not always associated with cytotoxicity effects and that there are some confounding factors that can affect the analysis. Finally, another drawback is that the correlation analysis between cellular impedance measurements and classical toxicity endpoints has been performed on a limited number of compounds. Overall, despite some limitations, the RTCA technology appears to be a powerful and reliable tool in drug discovery because of the reasonable throughput, rapid and efficient performance, technical optimization, and cell quality control.

  6. The Role of TCA Cycle Anaplerosis in Ketosis and Fatty Liver in Periparturient Dairy Cows

    PubMed Central

    White, Heather M.

    2015-01-01

    The transition to lactation period in dairy cattle is characterized by metabolic challenges, negative energy balance, and adipose tissue mobilization. Metabolism of mobilized adipose tissue is part of the adaptive response to negative energy balance in dairy cattle; however, the capacity of the liver to completely oxidize nonesterified fatty acids may be limited and is reflective of oxaloacetate pool, the carbon carrier of the tricarboxylic acid cycle. Alternative metabolic fates of acetyl-CoA from nonesterified fatty acids include esterification to triacylglycerides and ketogenesis, and when excessive, these pathways lead to fatty liver and ketosis. Examination of the anaplerotic and cataplerotic pull of oxaloacetate by the tricarboxylic acid cycle and gluconeogenesis may provide insight into the balance of oxidation and esterification of acetyl-CoA within the liver of periparturient dairy cows. PMID:26479386

  7. The Role of TCA Cycle Anaplerosis in Ketosis and Fatty Liver in Periparturient Dairy Cows.

    PubMed

    White, Heather M

    2015-08-18

    The transition to lactation period in dairy cattle is characterized by metabolic challenges, negative energy balance, and adipose tissue mobilization. Metabolism of mobilized adipose tissue is part of the adaptive response to negative energy balance in dairy cattle; however, the capacity of the liver to completely oxidize nonesterified fatty acids may be limited and is reflective of oxaloacetate pool, the carbon carrier of the tricarboxylic acid cycle. Alternative metabolic fates of acetyl-CoA from nonesterified fatty acids include esterification to triacylglycerides and ketogenesis, and when excessive, these pathways lead to fatty liver and ketosis. Examination of the anaplerotic and cataplerotic pull of oxaloacetate by the tricarboxylic acid cycle and gluconeogenesis may provide insight into the balance of oxidation and esterification of acetyl-CoA within the liver of periparturient dairy cows.

  8. The effect of propionic acid and valeric acid on the cell cycle in root meristems of Pisum sativum

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

    Tramontano, W.A.; Yang, Shauyu; Delillo, A.R.

    1990-01-01

    Propionic acid and valeric acid at 1mM reduced the mitotic index of root meristem cells of Pisum sativum to < 1% after 12 hr in aerated White's medium. This effect varied with different acid concentrations. After a 12 hr exposure to either acid, seedlings transferred to fresh medium without either acid, resumed their normal mitotic index after 12 hr, with a burst of mitosis 8 hr post-transfer. Exposure of root meristem cells to either acid also inhibited ({sup 3}H)-TdR incorporation. Neither acid significantly altered the distribution of meristematic cells in G1 and G2 after 12 hr. The incorporation of ({supmore » 3}H) - uridine was also unaltered by the addition of either acid. This information suggests that propionic acid and valeric acid, limit progression through the cell cycle by inhibiting DNA synthesis and arresting cells in G1 and G2. These results were consistent with previous data which utilized butyric acid.« less

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

    Galatola, G.; Jazrawi, R.P.; Bridges, C.

    The purpose of this study was to develop and validate a method of directly measuring ileal bile acid absorption efficiency during a single enterohepatic cycle (first-pass ileal clearance). This has become feasible for the first time because of the availability of the synthetic gamma-labeled bile acid 75Selena-homocholic acid-taurine (75SeHCAT). Together with the corresponding natural bile acid cholic acid-taurine (labeled with 14C), SeHCAT was infused distal to an occluding balloon situated beyond the ampulla of Vater in six healthy subjects. Completion of a single enterohepatic cycle was assessed by obtaining a plateau for 75SeHCAT activity proximal to the occluding balloon, whichmore » prevented further cycles. Unabsorbed 75SeHCAT was collected after total gut washout, which was administered distal to the occluding balloon. 75SeHCAT activity in the rectal effluent measured by gamma counter was compared with that of absorbed 75SeHCAT level measured by gamma camera and was used to calculate first-pass ileal clearance. This was very efficient (mean value, 96%) and showed very little variation in the six subjects studied (range, 95%-97%). A parallel time-activity course in hepatic bile for 14C and 75Se during a single enterohepatic cycle, together with a ratio of unity for 14C/75Se in samples obtained at different time intervals, suggests that 75SeHCAT is handled by the ileum like the natural bile acid cholic acid-taurine. Extrapolation of 75SeHCAT first-pass ileal clearance to that of the natural bile acid therefore seems justifiable. In a subsidiary experiment, ileal absorption efficiency per day for 75SeHCAT was also measured by scanning the gallbladder area on 5 successive days after the measurement of first-pass ileal clearance. In contrast with absorption efficiency per cycle, absorption efficiency per day varied widely (49%-86%).« less

  10. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  11. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries) were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  12. The antidiabetic drug metformin decreases mitochondrial respiration and tricarboxylic acid cycle activity in cultured primary rat astrocytes.

    PubMed

    Hohnholt, Michaela C; Blumrich, Eva-Maria; Waagepetersen, Helle S; Dringen, Ralf

    2017-11-01

    Metformin is an antidiabetic drug that is used daily by millions of patients worldwide. Metformin is able to cross the blood-brain barrier and has recently been shown to increase glucose consumption and lactate release in cultured astrocytes. However, potential effects of metformin on mitochondrial tricarboxylic acid (TCA) cycle metabolism in astrocytes are unknown. We investigated this by mapping 13 C labeling in TCA cycle intermediates and corresponding amino acids after incubation of primary rat astrocytes with [U- 13 C]glucose. The presence of metformin did not compromise the viability of cultured astrocytes during 4 hr of incubation, but almost doubled cellular glucose consumption and lactate release. Compared with control cells, the presence of metformin dramatically lowered the molecular 13 C carbon labeling (MCL) of the cellular TCA cycle intermediates citrate, α-ketoglutarate, succinate, fumarate, and malate, as well as the MCL of the TCA cycle intermediate-derived amino acids glutamate, glutamine, and aspartate. In addition to the total molecular 13 C labeling, analysis of the individual isotopomers of TCA cycle intermediates confirmed a severe decline in labeling and a significant lowering in TCA cycling ratio in metformin-treated astrocytes. Finally, the oxygen consumption of mitochondria isolated from metformin-treated astrocytes was drastically reduced in the presence of complex I substrates, but not of complex II substrates. These data demonstrate that exposure to metformin strongly impairs complex I-mediated mitochondrial respiration in astrocytes, which is likely to cause the observed decrease in labeling of mitochondrial TCA cycle intermediates and the stimulation of glycolytic lactate production. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Malonyl-CoA Decarboxylase (MCD) as a Potential Therapeutic Target for Breast Cancer

    DTIC Science & Technology

    2010-05-01

    Kreb cycle and electron transport activity. Clinical and biochemical studies of MCD deficiency, a rare inborn error of metabolism, provide another... mitochondria and is the rate limiting enzymatic step of mitochondrial fatty acid oxidation (Figure 1) (McGarry and Brown, 1997). Indeed, the 10-fold...1 activity and fatty acid oxidation, thereby preventing a futile cycle of fatty acid synthesis and oxidation. As FAS could consume malonyl-CoA, it was

  14. A Brownian motor mechanism of translocation and strand separation by hepatitis C virus helicase.

    PubMed

    Levin, Mikhail K; Gurjar, Madhura; Patel, Smita S

    2005-05-01

    Helicases translocate along their nucleic acid substrates using the energy of ATP hydrolysis and by changing conformations of their nucleic acid-binding sites. Our goal is to characterize the conformational changes of hepatitis C virus (HCV) helicase at different stages of ATPase cycle and to determine how they lead to translocation. We have reported that ATP binding reduces HCV helicase affinity for nucleic acid. Now we identify the stage of the ATPase cycle responsible for translocation and unwinding. We show that a rapid directional movement occurs upon helicase binding to DNA in the absence of ATP, resulting in opening of several base pairs. We propose that HCV helicase translocates as a Brownian motor with a simple two-stroke cycle. The directional movement step is fueled by single-stranded DNA binding energy while ATP binding allows for a brief period of random movement that prepares the helicase for the next cycle.

  15. Diel cycling of zinc in a stream impacted by acid rock drainage: Initial results from a new in situ Zn analyzer

    USGS Publications Warehouse

    Chapin, T.P.; Nimick, D.A.; Gammons, C.H.; Wanty, R.B.

    2007-01-01

    Recent work has demonstrated that many trace metals undergo dramatic diel (24-h) cycles in near neutral pH streams with metal concentrations reproducibly changing up to 500% during the diel period (Nimick et al., 2003). To examine diel zinc cycles in streams affected by acid rock drainage, we have developed a novel instrument, the Zn-DigiScan, to continuously monitor in situ zinc concentrations in near real-time. Initial results from a 3-day deployment at Fisher Creek, Montana have demonstrated the ability of the Zn-DigiScan to record diel Zn cycling at levels below 100 ??g/l. Longer deployments of this instrument could be used to examine the effects of episodic events such as rainstorms and snowmelt pulses on zinc loading in streams affected by acid rock drainage. ?? Springer Science+Business Media B.V. 2006.

  16. [Changes in molecular forms of sex hormone binding globulin during menstrual cycle and menopause].

    PubMed

    Fonseca, M E; Masón, M; Ochoa, R; Hernández-V, M; Zárate, A

    1996-11-01

    Sex hormone binding globulin (SHBG) is a glycoprotein that transports mainly androgens and estrogens regulating the amount of free and bound hormone which in turn plays a role in the metabolic balance. It is also known that estrogens increase the hepatic production of SHBG which circulates in various molecular forms containing different amounts of sialic acid as the main component of carbohydrates. In the present work we studied physiological variations of molecular forms of SHBG during the normal menstrual cycle and the menopause. During the follicular phase the form 54 KD was the predominant variant, in the periovulatory period was isomers 90 KD, and during the luteal phase corresponded to both 54 and 90 KD. In the menopause dimeric form of 90 KD corresponded to the major proportion and was present a higher molecular forms of 115-135 KD. Following estrogen therapy the chromatographic profile changed as to that observed during the menstrual cycle. Important changes in the proportion of sialic acid were observed in each of the phases of menstrual cycle and following estrogen replacement. And increase in the amount of sialic acid corresponded to higher estrogen concentrations. It is concluded that SHBG concentrations varies during the menstrual cycle according the estrogen levels which in addition regulates the proportion of molecular forms and sialic acid containt.

  17. The metabolism of galactose in the human gastric mucous membrane.

    PubMed

    Kopacz-Jodczyk, T; Zwierz, K; Gałasiński, W

    1984-12-01

    After incubating pieces of human gastric mucous membrane with radioactive galactose, labeled metabolites of glycolysis (FDP,PEP,pyruvate):hexose and hexosamine intermediates in glycoconjugate biosynthesis (gal-1P, UDP-gal,acetylated hexosamines, and their phosphate esters), amino acids (glycine, alanine, and serine), and oxoglutarate as a metabolite of the citric acid cycle were isolated from the acid-soluble fraction. These results suggest that galactose in the human gastric mucous membrane is epimerized to glucose and metabolized in the glycolytic pathway together with oxidation in the citric acid cycle and in the direction of glycoconjugate biosynthesis.

  18. Phosphoric acid as an electrolyte additive for lead/acid batteries in electric-vehicle applications

    NASA Astrophysics Data System (ADS)

    Meissner, E.

    The influence of the addition of phosphoric acid to the electrolyte on the performance of gelled lead/acid electric-vehiicle batteries is investigated. This additive reduces the reversible capacity decay of the positive electrode significantly which is observed upon extended cycling when recharge of the battery is performed at low initial rate. This is important when low-rate on-board chargers are used. Pulsed discharge, typical for electric-vehicle application, induces reversible capacity decay more than constant-current discharge at a same depth-of-discharge, as well with as without the addition of phosphoric acid. By contrast, hindrance in presence of H 3PO 4 for both the recharge and the discharge reaction helps to homogenize the state of many individual cells during cycling in long battery strings. Reversible capacity loss, which occurs after extended cycling and when pulsed discharge is applied, can be recovered by a single discharge at very low rate with batteries with and without the addition of phosphoric acid. The discharge-rate dependency of the capacity is significantly reduced when phosphoric acid is added. The pulse discharge behaviour may be better, even if the nominal capacity is reduced. The experimental findings of the influence of phosphoric acid addition is discussed in terms of the aggregate-of-spheres model of reversible capacity decay.

  19. Production of Caproic Acid from Mixed Organic Waste: An Environmental Life Cycle Perspective

    PubMed Central

    2017-01-01

    Caproic acid is an emerging platform chemical with diverse applications. Recently, a novel biorefinery process, that is, chain elongation, was developed to convert mixed organic waste and ethanol into renewable caproic acids. In the coming years, this process may become commercialized, and continuing to improve on the basis of numerous ongoing technological and microbiological studies. This study aims to analyze the environmental performance of caproic acid production from mixed organic waste via chain elongation at this current, early stage of technological development. To this end, a life cycle assessment (LCA) was performed to evaluate the environmental impact of producing 1 kg caproic acid from organic waste via chain elongation, in both a lab-scale and a pilot-scale system. Two mixed organic waste were used as substrates: the organic fraction of municipal solid waste (OFMSW) and supermarket food waste (SFW). Ethanol use was found to be the dominant cause of environmental impact over the life cycle. Extraction solvent recovery was found to be a crucial uncertainty that may have a substantial influence on the life-cycle impacts. We recommend that future research and industrial producers focus on the reduction of ethanol use in chain elongation and improve the recovery efficiency of the extraction solvent. PMID:28513150

  20. [Plasma concentrations of folic acid, vitamin B12 and progesterone of cyclic bitches, bitches during pregnancy and induced abortion and bitches with pyometra].

    PubMed

    Kalender, H; Beceriklisoy, H B; Kanca, H; Findik, M; Erünal-Maral, N; Handler, J; Aslan, S

    2006-09-01

    The aim of this study was to investigate the plasma concentrations of folic acid, vitamin B12 and progesterone at different stages of the sexual cycle and pregnancy, during induced abortion and in bitches with pyometra. Bitches (n = 97) were assigned to groups as follows: a) oestrous cycle (n = 42) b) pregnancy (n = 25) c) induction of abortion (n = 10 and d) pyometra (n = 20). Oestrous cycle stages were determined by vaginal inspection and cytology. Pregnancies were estimated by ultrasound (5.0 Mhz; linear transducer; Schimadzu) at days 15-25, 35-45 and 46-63 of pregnancy. Treatments for the induction of abortion were started between days 25 and 35 after mating (5 microg/kg cabergoline daily, Galastop; 5-10 microg/kg Alfaprostol every other day, Gabbrostim). Diagnosis of pyometra was confirmed by ultrasound and vaginoscopy. Folic acid and vitamin B12 concentrations did not differ among different stages of the oestrous cycle. The mean concentration of folic acid during early pregnancy (days 15-25) exceeded levels of later stages (days 46-63): 9.4 +/- 3.7 microg/ml and 4.7 +/- 1.8 microg/ml, respectively (p < 0.01). A positive correlation between folic acid and vitamin B12 was determined in pregnant dogs ( r = 0.925; p < 0.02). Before the induction of abortion, the concentration of folic acid was 9.6 +/- 5.2 microg/ml; during abortion it decreased to 5.0 +/- 3.2 microg/ml (p < 0.01). A significant correlation (r = 0.925; p < 0.02) between progesterone and folic acid was obtained in bitches with abortion. The mean concentration of folic acid in bitches with pyometra significantly differed from that of bitches at different stages of the oestrous cycle (p < 0.05). The mean concentration of folic acid was significantly lower in metoestrous bitches when compared to bitches with pyometra (p < 0.05). The decrease of serum concentrations of folic acid during pregnancy and induced abortion show that fetal growth and abortion caused higher consumption of folic acid. Concerning bitches did not show any deficiency symptoms, which is why it can be concluded that this decrease is physiological.

  1. 'Trophic' and 'source' amino acids in trophic estimation: a likely metabolic explanation.

    PubMed

    O'Connell, T C

    2017-06-01

    Amino acid nitrogen isotopic analysis is a relatively new method for estimating trophic position. It uses the isotopic difference between an individual's 'trophic' and 'source' amino acids to determine its trophic position. So far, there is no accepted explanation for the mechanism by which the isotopic signals in 'trophic' and 'source' amino acids arise. Yet without a metabolic understanding, the utility of nitrogen isotopic analyses as a method for probing trophic relations, at either bulk tissue or amino acid level, is limited. I draw on isotopic tracer studies of protein metabolism, together with a consideration of amino acid metabolic pathways, to suggest that the 'trophic'/'source' groupings have a fundamental metabolic origin, to do with the cycling of amino-nitrogen between amino acids. 'Trophic' amino acids are those whose amino-nitrogens are interchangeable, part of a metabolic amino-nitrogen pool, and 'source' amino acids are those whose amino-nitrogens are not interchangeable with the metabolic pool. Nitrogen isotopic values of 'trophic' amino acids will reflect an averaged isotopic signal of all such dietary amino acids, offset by the integrated effect of isotopic fractionation from nitrogen cycling, and modulated by metabolic and physiological effects. Isotopic values of 'source' amino acids will be more closely linked to those of equivalent dietary amino acids, but also modulated by metabolism and physiology. The complexity of nitrogen cycling suggests that a single identifiable value for 'trophic discrimination factors' is unlikely to exist. Greater consideration of physiology and metabolism should help in better understanding observed patterns in nitrogen isotopic values.

  2. Soil Rhizosphere Microbial Communities and Enzyme Activities under Organic Farming

    USDA-ARS?s Scientific Manuscript database

    This study investigated the activities of ß-glucosidase (C cycling, ß-glucosaminidase (C and N cycling), acid phosphatase (P cycling) and arylsulfatase (S cycling) under lettuce (Lactuca sativa), potato (Solanum Tuberosum), onion (Allium cepa L), broccoli (Brassica oleracea var. botrytis) and Tall f...

  3. Resin-dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding. Part II: Effects of mechanical cycling load on microtensile bond strengths.

    PubMed

    Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H; Tay, Franklin R; Watson, Timothy F; Osorio, Raquel

    2011-06-01

    To compare microtensile bond strengths (MTBS) subsequent to load cycling of resin bonded acid-etched or EDTA-treated dentin using a modified ethanol wet-bonding technique. Flat dentin surfaces were obtained from extracted human molars and conditioned using 37% H(3)PO(4) (PA) (15s) or 0.1M EDTA (60s). Five experimental adhesives and one commercial bonding agent were applied to the dentin and light-cured. Solvated experimental resins (50% ethanol/50% comonomers) were used as primers and their respective neat resins were used as the adhesives. The resin-bonded teeth were stored in distilled water (24h) or submitted to 5000 loading cycles of 90N. The bonded teeth were then sectioned in beams for MTBS. Modes of failure were examined by scanning electron microscopy. The most hydrophobic resin 1 gave the lowest bond strength values to both acid and EDTA-treated dentin. The hydrophobic resin 2 applied to EDTA-treated dentin showed lower bond strengths after cycling load but this did not occur when it was bonded to PA-etched dentin. Resins 3 and 4, which contained hydrophilic monomers, gave higher bond strengths to both EDTA-treated or acid-etched dentin and showed no significant difference after load cycling. The most hydrophilic resin 5 showed no significant difference in bond strengths after cycling loading when bonded to EDTA or phosphoric acid treated dentin but exhibited low bond strengths. The presence of different functional monomers influences the MTBS of the adhesive systems when submitted to cyclic loads. Adhesives containing hydrophilic comonomers are not affected by cycling load challenge especially when applied on EDTA-treated dentin followed by ethanol wet bonding. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  4. IKOS: A Framework for Static Analysis based on Abstract Interpretation (Tool Paper)

    NASA Technical Reports Server (NTRS)

    Brat, Guillaume P.; Laserna, Jorge A.; Shi, Nija; Venet, Arnaud Jean

    2014-01-01

    The RTCA standard (DO-178C) for developing avionic software and getting certification credits includes an extension (DO-333) that describes how developers can use static analysis in certification. In this paper, we give an overview of the IKOS static analysis framework that helps developing static analyses that are both precise and scalable. IKOS harnesses the power of Abstract Interpretation and makes it accessible to a larger class of static analysis developers by separating concerns such as code parsing, model development, abstract domain management, results management, and analysis strategy. The benefits of the approach is demonstrated by a buffer overflow analysis applied to flight control systems.

  5. GCS programmer's manual

    NASA Technical Reports Server (NTRS)

    Lowman, Douglas S.; Withers, B. Edward; Shagnea, Anita M.; Dent, Leslie A.; Hayhurst, Kelly J.

    1990-01-01

    A variety of instructions to be used in the development of implementations of software for the Guidance and Control Software (GCS) project is described. This document fulfills the Radio Technical Commission for Aeronautics RTCA/DO-178A guidelines, 'Software Considerations in Airborne Systems and Equipment Certification' requirements for document No. 4, which specifies the information necessary for understanding and programming the host computer, and document No. 12, which specifies the software design and implementation standards that are applicable to the software development and testing process. Information on the following subjects is contained: activity recording, communication protocol, coding standards, change management, error handling, design standards, problem reporting, module testing logs, documentation formats, accuracy requirements, and programmer responsibilities.

  6. Charge Efficiency Tests of Lead/Acid Batteries

    NASA Technical Reports Server (NTRS)

    Rowlette, J. J.

    1984-01-01

    Current, voltage, and gas evolution measured during charge/discharge cycles. Series of standarized tests for evaluating charging efficiency of lead/acid storage batteries described in report. Purpose of tests to provide information for design of battery charger that allows maximum recharge efficiency for electric-vehicle batteries consistent with other operating parameters, such as range, water loss, and cycle life.

  7. Gamma-irradiation of malic acid in aqueous solutions. [prebiotic significance

    NASA Technical Reports Server (NTRS)

    Negron-Mendoza, A.; Graff, R. L.; Ponnamperuma, C.

    1980-01-01

    The gamma-irradiation of malic acid in aqueous solutions was studied under initially oxygenated and oxygen-free conditions in an attempt to determine the possible interconversion of malic acid into other carboxylic acids, specifically those associated with Krebs cycle. The effect of dose on product formation of the system was investigated. Gas-liquid chromatography combined with mass spectrometry was used as the principal means of identification of the nonvolatile products. Thin layer chromatography and direct probe mass spectroscopy were also employed. The findings show that a variety of carboxylic acids are formed, with malonic and succinic acids in greatest abundance. These products have all been identified as being formed in the gamma-irradiation of acetic acid, suggesting a common intermediary. Since these molecules fit into a metabolic cycle, it is strongly suggestive that prebiotic pathways provided the basis for biological systems.

  8. Diversity of the microbiota involved in wine and organic apple cider submerged vinegar production as revealed by DHPLC analysis and next-generation sequencing.

    PubMed

    Trček, Janja; Mahnič, Aleksander; Rupnik, Maja

    2016-04-16

    Unfiltered vinegar samples collected from three oxidation cycles of the submerged industrial production of each, red wine and organic apple cider vinegars, were sampled in a Slovene vinegar producing company. The samples were systematically collected from the beginning to the end of an oxidation cycle and used for culture-independent microbial analyses carried out by denaturing high pressure liquid chromatography (DHPLC) and Illumina MiSeq sequencing of 16S rRNA gene variable regions. Both approaches showed a very homogeneous bacterial structure during wine vinegar production but more heterogeneous during organic apple cider vinegar production. In all wine vinegar samples Komagataeibacter oboediens (formerly Gluconacetobacter oboediens) was a predominating species. In apple cider vinegar the acetic acid and lactic acid bacteria were two major groups of bacteria. The acetic acid bacterial consortium was composed of Acetobacter and Komagataeibacter with the Komagataeibacter genus outcompeting the Acetobacter in all apple cider vinegar samples at the end of oxidation cycle. Among the lactic acid bacterial consortium two dominating genera were identified, Lactobacillus and Oenococcus, with Oenococcus prevailing with increasing concentration of acetic acid in vinegars. Unexpectedly, a minor genus of the acetic acid bacterial consortium in organic apple cider vinegar was Gluconobacter, suggesting a possible development of the Gluconobacter population with a tolerance against ethanol and acetic acid. Among the accompanying bacteria of the wine vinegar, the genus Rhodococcus was detected, but it decreased substantially by the end of oxidation cycles. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Integrated Analysis of the Transcriptome and Metabolome of Corynebacterium glutamicum during Penicillin-Induced Glutamic Acid Production.

    PubMed

    Hirasawa, Takashi; Saito, Masaki; Yoshikawa, Katsunori; Furusawa, Chikara; Shmizu, Hiroshi

    2018-05-01

    Corynebacterium glutamicum is known for its ability to produce glutamic acid and has been utilized for the fermentative production of various amino acids. Glutamic acid production in C. glutamicum is induced by penicillin. In this study, the transcriptome and metabolome of C. glutamicum is analyzed to understand the mechanism of penicillin-induced glutamic acid production. Transcriptomic analysis with DNA microarray revealed that expression of some glycolysis- and TCA cycle-related genes, which include those encoding the enzymes involved in conversion of glucose to 2-oxoglutaric acid, is upregulated after penicillin addition. Meanwhile, expression of some TCA cycle-related genes, encoding the enzymes for conversion of 2-oxoglutaric acid to oxaloacetic acid, and the anaplerotic reactions decreased. In addition, expression of NCgl1221 and odhI, encoding proteins involved in glutamic acid excretion and inhibition of the 2-oxoglutarate dehydrogenase, respectively, is upregulated. Functional category enrichment analysis of genes upregulated and downregulated after penicillin addition revealed that genes for signal transduction systems are enriched among upregulated genes, whereas those for energy production and carbohydrate and amino acid metabolisms are enriched among the downregulated genes. As for the metabolomic analysis using capillary electrophoresis time-of-flight mass spectrometry, the intracellular content of most metabolites of the glycolysis and the TCA cycle decreased dramatically after penicillin addition. Overall, these results indicate that the cellular metabolism and glutamic acid excretion are mainly optimized at the transcription level during penicillin-induced glutamic acid production by C. glutamicum. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. 75 FR 40736 - Acetic Acid; Exemption from the Requirement of a Tolerance

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... known as the citric acid (Ref. 1.) or krebs cycle (Ref. 2.), which is the chemical activity in all cells... as antibiotics, antibacterials and antimicrobials. Acetic acid is also the main acid in vinegars, and...

  11. Sulfa drugs inhibit sepiapterin reduction and chemical redox cycling by sepiapterin reductase.

    PubMed

    Yang, Shaojun; Jan, Yi-Hua; Mishin, Vladimir; Richardson, Jason R; Hossain, Muhammad M; Heindel, Ned D; Heck, Diane E; Laskin, Debra L; Laskin, Jeffrey D

    2015-03-01

    Sepiapterin reductase (SPR) catalyzes the reduction of sepiapterin to dihydrobiopterin (BH2), the precursor for tetrahydrobiopterin (BH4), a cofactor critical for nitric oxide biosynthesis and alkylglycerol and aromatic amino acid metabolism. SPR also mediates chemical redox cycling, catalyzing one-electron reduction of redox-active chemicals, including quinones and bipyridinium herbicides (e.g., menadione, 9,10-phenanthrenequinone, and diquat); rapid reaction of the reduced radicals with molecular oxygen generates reactive oxygen species (ROS). Using recombinant human SPR, sulfonamide- and sulfonylurea-based sulfa drugs were found to be potent noncompetitive inhibitors of both sepiapterin reduction and redox cycling. The most potent inhibitors of sepiapterin reduction (IC50s = 31-180 nM) were sulfasalazine, sulfathiazole, sulfapyridine, sulfamethoxazole, and chlorpropamide. Higher concentrations of the sulfa drugs (IC50s = 0.37-19.4 μM) were required to inhibit redox cycling, presumably because of distinct mechanisms of sepiapterin reduction and redox cycling. In PC12 cells, which generate catecholamine and monoamine neurotransmitters via BH4-dependent amino acid hydroxylases, sulfa drugs inhibited both BH2/BH4 biosynthesis and redox cycling mediated by SPR. Inhibition of BH2/BH4 resulted in decreased production of dopamine and dopamine metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid, and 5-hydroxytryptamine. Sulfathiazole (200 μM) markedly suppressed neurotransmitter production, an effect reversed by BH4. These data suggest that SPR and BH4-dependent enzymes, are "off-targets" of sulfa drugs, which may underlie their untoward effects. The ability of the sulfa drugs to inhibit redox cycling may ameliorate ROS-mediated toxicity generated by redox active drugs and chemicals, contributing to their anti-inflammatory activity. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  12. Interactions in the Metabolism of Glutamate and the Branched-Chain Amino Acids and Ketoacids in the CNS.

    PubMed

    Yudkoff, Marc

    2017-01-01

    Glutamatergic neurotransmission entails a tonic loss of glutamate from nerve endings into the synapse. Replacement of neuronal glutamate is essential in order to avoid depletion of the internal pool. In brain this occurs primarily via the glutamate-glutamine cycle, which invokes astrocytic synthesis of glutamine and hydrolysis of this amino acid via neuronal phosphate-dependent glutaminase. This cycle maintains constancy of internal pools, but it does not provide a mechanism for inevitable losses of glutamate N from brain. Import of glutamine or glutamate from blood does not occur to any appreciable extent. However, the branched-chain amino acids (BCAA) cross the blood-brain barrier swiftly. The brain possesses abundant branched-chain amino acid transaminase activity which replenishes brain glutamate and also generates branched-chain ketoacids. It seems probable that the branched-chain amino acids and ketoacids participate in a "glutamate-BCAA cycle" which involves shuttling of branched-chain amino acids and ketoacids between astrocytes and neurons. This mechanism not only supports the synthesis of glutamate, it also may constitute a mechanism by which high (and potentially toxic) concentrations of glutamate can be avoided by the re-amination of branched-chain ketoacids.

  13. Results of chopper-controlled discharge life cycling studies on lead acid batteries

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.; Sidik, S. M.

    1982-01-01

    A group of 108 state of the art nominally 6 volt lead acid batteries were tested in a program of one charge/discharge cycle per day for over two years or to ultimate battery failure. The primary objective was to determine battery cycle life as a function of depth of discharge (25 to 75 percent), chopper frequency (100 to 1000 Hz), duty cycle (25 to 87.5 percent), and average discharge current (20 to 260 A). The secondary objective was to determine the types of battery failure modes, if any, were due to the above parameters. The four parameters above were incorporated in a statistically designed test program.

  14. Urinary Loss of Tricarboxylic Acid Cycle Intermediates As Revealed by Metabolomics Studies: An Underlying Mechanism to Reduce Lipid Accretion by Whey Protein Ingestion?

    PubMed Central

    2015-01-01

    Whey protein intake is associated with the modulation of energy metabolism and altered body composition both in human subjects and in animals, but the underlying mechanisms are not yet elucidated. We fed obesity-prone C57BL/6J mice high-fat diets with either casein (HF casein) or whey (HF whey) for 6 weeks. At equal energy intake and apparent fat and nitrogen digestibility, mice fed HF whey stored less energy as lipids, evident both as lower white adipose tissue mass and as reduced liver lipids, compared with HF-casein-fed mice. Explorative analyses of 48 h urine, both by 1H NMR and LC–MS metabolomic platforms, demonstrated higher urinary excretion of tricarboxylic acid (TCA) cycle intermediates citric acid and succinic acid (identified by both platforms), and cis-aconitic acid and isocitric acid (identified by LC–MS platform) in the HF whey, relative to in the HF-casein-fed mice. Targeted LC–MS analyses revealed higher citric acid and cis-aconitic acid concentrations in fed state plasma, but not in liver of HF-whey-fed mice. We propose that enhanced urinary loss of TCA cycle metabolites drain available substrates for anabolic processes, such as lipogenesis, thereby leading to reduced lipid accretion in HF-whey-fed compared to HF-casein-fed mice. PMID:24702026

  15. Ester-Mediated Amide Bond Formation Driven by Wet-Dry Cycles: A Possible Path to Polypeptides on the Prebiotic Earth.

    PubMed

    Forsythe, Jay G; Yu, Sheng-Sheng; Mamajanov, Irena; Grover, Martha A; Krishnamurthy, Ramanarayanan; Fernández, Facundo M; Hud, Nicholas V

    2015-08-17

    Although it is generally accepted that amino acids were present on the prebiotic Earth, the mechanism by which α-amino acids were condensed into polypeptides before the emergence of enzymes remains unsolved. Here, we demonstrate a prebiotically plausible mechanism for peptide (amide) bond formation that is enabled by α-hydroxy acids, which were likely present along with amino acids on the early Earth. Together, α-hydroxy acids and α-amino acids form depsipeptides-oligomers with a combination of ester and amide linkages-in model prebiotic reactions that are driven by wet-cool/dry-hot cycles. Through a combination of ester-amide bond exchange and ester bond hydrolysis, depsipeptides are enriched with amino acids over time. These results support a long-standing hypothesis that peptides might have arisen from ester-based precursors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Aldehyde-alcohol reactions catalyzed under mild conditions by chromium(III) terephthalate metal organic framework (MIL-101) and phosphotungstic acid composites.

    PubMed

    Bromberg, Lev; Hatton, T Alan

    2011-12-01

    Porous materials based on chromium(III) terephthalate metal organic frameworks (MIL-101) and their composites with phosphotungstic acid (PTA) were studied as heterogeneous acid catalysts in aldehyde-alcohol reactions exemplified by acetaldehyde-phenol (A-P) condensation and dimethylacetal formation from benzaldehyde and methanol (B-M reaction). The MIL-101 was synthesized solvothermically in water, and the MIL101/PTA composite materials were obtained by either impregnation of the already prepared MIL-101 porous matrix with phosphotungstic acid solution or by solvothermic treatment of aqueous mixtures of Cr(NO(3))(3), and terephthalic and phosphotungstic acids. The MIL101/PTA materials appeared to be effective catalysts for both A-P and B-M reactions occurring at room temperature, with half-lives ranging from 0.5 h (A-P) to 1.5-2 h (B-M) and turnover numbers over 600 for A-P and over 2900 for the B-M reaction, respectively. A synergistic effect of the strong acidic moieties (PTA) addition to mildly acidic Brønsted and Lewis acid cites of the MIL-101 was observed with the MIL101/PTA composites. The ability of the PTA and MIL101/PTA materials to strongly absorb and condense acetaldehyde vapors was discovered, with the MIL101/PTA absorbing over 10-fold its dry weight of acetaldehyde condensate at room temperature. The acetaldehyde was converted rapidly to crotonaldehyde and higher-molecular-weight compounds while in contact with MIL-101 and MIL101/PTA materials. The stability of the MIL-101 and MIL101/PTA catalysts was assessed within four cycles of the 1-day alcohol-aldehyde reactions in terms of the overall catalyst recovery, PTA or Cr content, and reaction rate constants in each cycle. The loss of the catalyst over 4 cycles was approximately 10 wt % for all tested catalysts due to the incomplete recovery and minute dissolution of the components. The reaction rates in all cycles remained unchanged and the catalyst losses stopped after the third cycle. The developed MIL101/PTA composites appear to be feasible for industrial catalytic applications. © 2011 American Chemical Society

  17. Guidance and Control Software Project Data - Volume 1: Planning Documents

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J. (Editor)

    2008-01-01

    The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the planning documents from the GCS project. Volume 1 contains five appendices: A. Plan for Software Aspects of Certification for the Guidance and Control Software Project; B. Software Development Standards for the Guidance and Control Software Project; C. Software Verification Plan for the Guidance and Control Software Project; D. Software Configuration Management Plan for the Guidance and Control Software Project; and E. Software Quality Assurance Activities.

  18. Guidance and Control Software Project Data - Volume 3: Verification Documents

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J. (Editor)

    2008-01-01

    The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes the verification documents from the GCS project. Volume 3 contains four appendices: A. Software Verification Cases and Procedures for the Guidance and Control Software Project; B. Software Verification Results for the Pluto Implementation of the Guidance and Control Software; C. Review Records for the Pluto Implementation of the Guidance and Control Software; and D. Test Results Logs for the Pluto Implementation of the Guidance and Control Software.

  19. Residual Tensile Property of Plain Woven Jute Fiber/Poly(Lactic Acid) Green Composites during Thermal Cycling

    PubMed Central

    Katogi, Hideaki; Takemura, Kenichi; Akiyama, Motoki

    2016-01-01

    This study investigated the residual tensile properties of plain woven jute fiber reinforced poly(lactic acid) (PLA) during thermal cycling. Temperature ranges of thermal cycling tests were 35–45 °C and 35–55 °C. The maximum number of cycles was 103 cycles. The quasi-static tensile tests of jute fiber, PLA, and composite were conducted after thermal cycling tests. Thermal mechanical analyses of jute fiber and PLA were conducted after thermal cycling tests. Results led to the following conclusions. For temperatures of 35–45 °C, tensile strength of composite at 103 cycles decreased 10% compared to that of composite at 0 cycles. For temperatures of 35–55 °C, tensile strength and Young’s modulus of composite at 103 cycles decreased 15% and 10%, respectively, compared to that of composite at 0 cycles. Tensile properties and the coefficient of linear expansion of PLA and jute fiber remained almost unchanged after thermal cycling tests. From observation of a fracture surface, the length of fiber pull out in the fracture surface of composite at 103 cycles was longer than that of composite at 0 cycles. Therefore, tensile properties of the composite during thermal cycling were decreased, probably because of the decrease of interfacial adhesion between the fiber and resin. PMID:28773694

  20. Design of an efficient electrolyte circulation system for the lead-acid battery

    NASA Astrophysics Data System (ADS)

    Thuerk, D.

    The design and operation of an electrolyte circulation system are described. Application of lead acid batteries to electric vehicle and other repetitive deep cycle services produces a nondesirable state in the battery cells, electrolyte stratification. This stratification is the result of acid and water generation at the electrodes during cycling. With continued cycling, the extent of the stratification increases and prevents complete charging with low percentages of overcharge. Ultimately this results in extremely short life for the battery system. The stratification problem was overcome by substantially overcharging the battery. This abusive overcharge produces gassing rates sufficient to mix the electrolyte during the end portion of the charge. Overcharge, even though it is required to eliminate stratification, produces the undesirable results related to high voltage and gassing rates.

  1. Sirt3 promotes the urea cycle and fatty acid oxidation during dietary restriction

    PubMed Central

    Hallows, William C.; Yu, Wei; Smith, Brian C.; Devries, Mark K.; Ellinger, James J.; Someya, Shinichi; Shortreed, Michael R.; Prolla, Tomas; Markley, John L.; Smith, Lloyd M.; Zhao, Shimin; Guan, Kun-Liang; Denu, John M.

    2011-01-01

    Summary Emerging evidence suggests that protein acetylation is a broad-ranging regulatory mechanism. Here we utilize acetyl-peptide arrays and metabolomic analyses to identify substrates of mitochondrial deacetylase Sirt3. We identified ornithine transcarbamoylase (OTC) from the urea cycle, and enzymes involved in β-oxidation. Metabolomic analyses of fasted mice lacking Sirt3 (sirt3−/−) revealed alterations in β-oxidation and the urea cycle. Biochemical analysis demonstrated that Sirt3 directly deacetylates OTC and stimulates its activity. Mice under caloric restriction (CR) increased Sirt3 protein levels, leading to deacetylation and stimulation of OTC activity. In contrast, sirt3−/− mice failed to deacetylate OTC in response to CR. Inability to stimulate OTC under CR led to a failure to reduce orotic acid levels, a known outcome of OTC deficiency. Thus, Sirt3 directly regulates OTC activity and promotes the urea cycle during CR, and the results suggest that under low energy input, Sirt3 modulates mitochondria by promoting amino-acid catabolism and β-oxidation. PMID:21255725

  2. 13-cis Retinoic acid induces apoptosis and cell cycle arrest in human SEB-1 sebocytes.

    PubMed

    Nelson, Amanda M; Gilliland, Kathryn L; Cong, Zhaoyuan; Thiboutot, Diane M

    2006-10-01

    Isotretinoin (13-cis retinoic acid (13-cis RA)) is the most potent inhibitor of sebum production, a key component in the pathophysiology of acne, yet its mechanism of action remains largely unknown. The effects of 13-cis RA, 9-cis retinoic acid (9-cis RA), and all-trans retinoic acid (ATRA) on cell proliferation, apoptosis, and cell cycle proteins were examined in SEB-1 sebocytes and keratinocytes. 13-cis RA causes significant dose-dependent and time-dependent decreases in viable SEB-1 sebocytes. A portion of this decrease can be attributed to cell cycle arrest as evidenced by decreased DNA synthesis, increased p21 protein expression, and decreased cyclin D1. Although not previously demonstrated in sebocytes, we report that 13-cis RA induces apoptosis in SEB-1 sebocytes as shown by increased Annexin V-FITC staining, increased TUNEL staining, and increased cleaved caspase 3 protein. Furthermore, the ability of 13-cis RA to induce apoptosis cannot be recapitulated by 9-cis RA or ATRA, and it is not inhibited by the presence of a retinoid acid receptor (RAR) pan-antagonist AGN 193109. Taken together these data indicate that 13-cis RA causes cell cycle arrest and induces apoptosis in SEB-1 sebocytes by a RAR-independent mechanism, which contributes to its sebosuppressive effect and the resolution of acne.

  3. Preventive effect of fluoridated orthodontic resins subjected to high cariogenic challenges.

    PubMed

    Passalini, Paula; Fidalgo, Tatiana Kelly da Silva; Caldeira, Erika Machado; Gleiser, Rogerio; Nojima, Matilde da Cunha Gonçalves; Maia, Lucianne Cople

    2010-01-01

    The aim of the present study was to evaluate the in vitro caries preventive effect of fluoridated orthodontic resins under pH cycling with two types of acid demineralizing saliva. Brackets were bonded to 60 bovine incisors, using either Transbond Plus Color Change (n=30) or Orthodontic Fill Magic (n=30) orthodontic resins. Each group of resin was divided into 3 subgroups (n=10): immersion in remineralizing artificial saliva for 14 days, pH cycling with high cariogenic challenge in acid saliva with pH 5.5, and acid saliva with pH 4.5. After 14 days of pH cycling, the caries preventive effect on the development of white spot lesion was evaluated considering the presence of inhibition zones to white spot lesions using two scores: 0= absence and 1= presence. Kruskal Wallis and Mann-Whitney tests (a=0.05) were used. Formation of white spot lesions was observed only under pH cycling using acid saliva with pH 4.5; with Transbond Plus Color Change being significantly more effective (p<0.05) in preventing the appearance of white spot lesions effect than Orthodontic Fill Magic. The acidity of the demineralizing solution influenced the formation of white spot lesions around orthodontic brackets under highly cariogenic conditions. Transbond Plus Color Change resin presented higher caries preventive effect than Orthodontic Fill Magic.

  4. Levels of Arabidopsis thaliana Leaf Phosphatidic Acids, Phosphatidylserines, and Most Trienoate-Containing Polar Lipid Molecular Species Increase during the Dark Period of the Diurnal Cycle.

    PubMed

    Maatta, Sara; Scheu, Brad; Roth, Mary R; Tamura, Pamela; Li, Maoyin; Williams, Todd D; Wang, Xuemin; Welti, Ruth

    2012-01-01

    Previous work has demonstrated that plant leaf polar lipid fatty acid composition varies during the diurnal (dark-light) cycle. Fatty acid synthesis occurs primarily during the light, but fatty acid desaturation continues in the absence of light, resulting in polyunsaturated fatty acids reaching their highest levels toward the end of the dark period. In this work, Arabidopsis thaliana were grown at constant (21°C) temperature with 12-h light and 12-h dark periods. Collision induced dissociation time-of-flight mass spectrometry (MS) demonstrated that 16:3 and 18:3 fatty acid content in membrane lipids of leaves are higher at the end of the dark than at the end of the light period, while 16:1, 16:2, 18:0, and 18:1 content are higher at the end of the light period. Lipid profiling of membrane galactolipids, phospholipids, and lysophospholipids by electrospray ionization triple quadrupole MS indicated that the monogalactosyldiacylglycerol, phosphatidylglycerol, and phosphatidylcholine classes include molecular species whose levels are highest at end of the light period and others that are highest at the end of the dark period. The levels of phosphatidic acid (PA) and phosphatidylserine classes were higher at the end of the dark period, and molecular species within these classes either followed the class pattern or were not significantly changed in the diurnal cycle. Phospholipase D (PLD) is a family of enzymes that hydrolyzes phospholipids to produce PA. Analysis of several PLD mutant lines suggests that PLDζ2 and possibly PLDα1 may contribute to diurnal cycling of PA. The polar lipid compositional changes are considered in relation to recent data that demonstrate phosphatidylcholine acyl editing.

  5. Effect of myo-inositol and alpha-lipoic acid on oocyte quality in polycystic ovary syndrome non-obese women undergoing in vitro fertilization: a pilot study.

    PubMed

    Rago, R; Marcucci, I; Leto, G; Caponecchia, L; Salacone, P; Bonanni, P; Fiori, C; Sorrenti, G; Sebastianelli, A

    2015-01-01

    The aim of the present study was to evaluate the effectiveness of the combined administration of myo-inositol and α-lipoic acid in polycystic ovary syndrome (PCOS) patients with normal body mass index (BMI), who had previously undergone intracytoplasmic sperm injection (ICSI) and received myo-inositol alone. Thirty-six of 65 normal-weight patients affected by PCOS who did not achieve pregnancy and one patient who had a spontaneous abortion were re-enrolled and given a cycle of treatment with myo-inositol and α-lipoic acid. For all female partners of the treated couples, the endocrine-metabolic and ultrasound parameters, ovarian volume, oocyte and embryo quality, and pregnancy rates were assessed before and after three months of treatment and compared with those of previous in vitro fertilization (IVF) cycle(s). After supplementation of myo-inositol with α-lipoic acid, insulin levels, BMI and ovarian volume were significantly reduced compared with myo-inositol alone. No differences were found in the fertilization and cleavage rate or in the mean number of transferred embryos between the two different treatments, whereas the number of grade 1 embryos was significantly increased, with a significant reduction in the number of grade 2 embryos treated with myo-inositol plus α-lipoic acid. Clinical pregnancy was not significantly different with a trend for a higher percentage for of myo-inositol and α-lipoic acid compared to the myo-inositol alone group. Our preliminary data suggest that the supplementation of myo-inositol and α-lipoic acid in PCOS patients undergoing an IVF cycle can help to improve their reproductive outcome and also their metabolic profiles, opening potential for their use in long-term prevention of PCOS.

  6. Anaplerotic therapy in propionic acidemia.

    PubMed

    Longo, Nicola; Price, Leisa B; Gappmaier, Eduard; Cantor, Nancy L; Ernst, Sharon L; Bailey, Carrie; Pasquali, Marzia

    2017-09-01

    Propionic acidemia is a rare metabolic disorder caused by a deficiency of propionyl- CoA carboxylase, the enzyme converting propionyl-CoA to methylmalonyl-CoA that subsequently enters the citric acid cycle as succinyl-CoA. Patients with propionic acidemia cannot metabolize propionic acid, which combines with oxaloacetate to form methylcitric acid. This, with the defective supply of succinyl-CoA, may lead to a deficiency in citric acid cycle intermediates. The objective of this study was to determine whether supplements with glutamine (400mg/kg per day), citrate (7.5mEq/kg per day), or ornithine α-ketoglutarate (400mg/kg per day) (anaplerotic agents that could fill up the citric acid cycle) would affect plasma levels of glutamine and ammonia, the urinary excretion of Krebs cycle intermediates, and the clinical outcome in 3 patients with propionic acidemia. Each supplement was administered daily for four weeks with a two week washout period between supplements. The supplement that produced the most favorable changes was supplemented for 30 weeks following the initial study period and then for a 2 year extension. The urinary excretion of the Krebs cycle intermediates, α-ketoglutarate, succinate, and fumarate increased significantly compared to baseline during citrate supplementation, but not with the other two supplements. For this reason, citrate supplements were continued in the second part of the study. The urinary excretion of methylcitric acid and 3-hydroxypropionic acid did not change with any intervention. No significant changes in ammonia or glutamine levels were observed with any supplement. However, supplementation with any anaplerotic agents normalized the physiological buffering of ammonia by glutamate, with plasma glutamate and alanine levels significantly increasing, rather than decreasing with increasing ammonia levels. No significant side effects were observed with any therapy and safety labs (blood counts, chemistry and thyroid profile) remained unchanged. Motor and cognitive development was severely delayed before the trial and did not change significantly with therapy. Hospitalizations per year did not change during the trial period, but decreased significantly (p<0.05) in the 2years following the study (when citrate was continued) compared to the 2years before and during the study. These results indicate that citrate entered the Krebs cycle providing successful anaplerotic therapy by increasing levels of the downstream intermediates of the Krebs cycle: α-ketoglutarate, succinate and fumarate. Citrate supplements were safe and might have contributed to reduce hospitalizations in patients with propionic acidemia. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. A hybrid water-splitting cycle using copper sulfate and mixed copper oxides

    NASA Technical Reports Server (NTRS)

    Schreiber, J. D.; Remick, R. J.; Foh, S. E.; Mazumder, M. M.

    1980-01-01

    The Institute of Gas Technology has derived and developed a hybrid thermochemical water-splitting cycle based on mixed copper oxides and copper sulfate. Similar to other metal oxide-metal sulfate cycles that use a metal oxide to 'concentrate' electrolytically produced sulfuric acid, this cycle offers the advantage of producing oxygen (to be vented) and sulfur dioxide (to be recycled) in separate steps, thereby eliminating the need of another step to separate these gases. The conceptual process flow-sheet efficiency of the cycle promises to exceed 50%. It has been completely demonstrated in the laboratory with recycled materials. Research in the electrochemical oxidation of sulfur dioxide to produce sulfuric acid and hydrogen performed at IGT indicates that the cell performance goals of 200 mA/sq cm at 0.5 V will be attainable using relatively inexpensive electrode materials.

  8. A combined experimental and DFT study of active structures and self-cycle mechanisms of mononuclear tungsten peroxo complexes in oxidation reactions

    NASA Astrophysics Data System (ADS)

    Jin, Peng; Wei, Donghui; Wen, Yiqiang; Luo, Mengfei; Wang, Xiangyu; Tang, Mingsheng

    2011-04-01

    Tungsten peroxo complexes have been widely used in olefin epoxidation, alcohol oxidation, Baeyer-Villiger oxidation and other oxidation reactions, however, there is still not a unanimous viewpoint for the active structure of mononuclear tungsten peroxo complex by now. In this paper, the catalysis of mononuclear tungsten peroxo complexes 0- 5 with or without acidic ligands for the green oxidation of cyclohexene to adipic acid in the absence of organic solvent and phase-transfer catalyst has been researched in experiment. Then we have suggested two possible kinds of active structures of mononuclear tungsten peroxo complexes including peroxo ring ( nA, n = 0-1) and hydroperoxo ( nB, n = 0-1) structures, which have been investigated using density functional theory (DFT). Moreover, the calculations on self-cycle mechanisms involving the two types of active structures of tungsten peroxo complexes with and without oxalic acid ligand have also been carried out at the B3LYP/[LANL2DZ/6-31G(d, p)] level. The highest energy barrier are 26.17 kcal/mol ( 0A, peroxo ring structure without oxalic acid ligand), 23.91 kcal/mol ( 1A, peroxo ring structure with oxalic acid ligand), 18.19 kcal/mol ( 0B, hydroperoxo structure without oxalic acid ligand) and 13.10 kcal/mol ( 1B, hydroperoxo structure with oxalic acid ligand) in the four potential energy profiles, respectively. The results indicate that both the energy barriers of active structure self-cycle processes with oxalic acid ligands are lower than those without oxalic acid ligands, so the active structures with oxalic acid ligands should be easier to recycle, which is in good agreement with our experimental results. However, due to the higher energy of product than that of the reactant, the energy profile of the self-cycle process of 1B shows that the recycle of 1B could not occur at all in theory. Moreover, the crystal data of peroxo ring structure with oxalic acid ligand could be found in some experimental references. Thus, the viewpoint that the peroxo ring active structure should be the real active structure has been proved in this paper.

  9. Salicylic acid antagonizes abscisic acid inhibition of shoot growth and cell cycle progression in rice

    NASA Astrophysics Data System (ADS)

    Meguro, Ayano; Sato, Yutaka

    2014-04-01

    We analysed effects of abscisic acid (ABA, a negative regulatory hormone), alone and in combination with positive or neutral hormones, including salicylic acid (SA), on rice growth and expression of cell cycle-related genes. ABA significantly inhibited shoot growth and induced expression of OsKRP4, OsKRP5, and OsKRP6. A yeast two-hybrid assay showed that OsKRP4, OsKRP5, and OsKRP6 interacted with OsCDKA;1 and/or OsCDKA;2. When SA was simultaneously supplied with ABA, the antagonistic effect of SA completely blocked ABA inhibition. SA also blocked ABA inhibition of DNA replication and thymidine incorporation in the shoot apical meristem. These results suggest that ABA arrests cell cycle progression by inducing expression of OsKRP4, OsKRP5, and OsKRP6, which inhibit the G1/S transition, and that SA antagonizes ABA by blocking expression of OsKRP genes.

  10. Effect of tricarboxylic acid cycle regulator on carbon retention and organic component transformation during food waste composting.

    PubMed

    Lu, Qian; Zhao, Yue; Gao, Xintong; Wu, Junqiu; Zhou, Haixuan; Tang, Pengfei; Wei, Qingbin; Wei, Zimin

    2018-05-01

    Composting is an environment friendly method to recycling organic waste. However, with the increasing concern about greenhouse gases generated in global atmosphere, it is significant to reduce the emission of carbon dioxide (CO 2 ). This study analyzes tricarboxylic acid (TCA) cycle regulators on the effect of reducing CO 2 emission, and the relationship among organic component (OC) degradation and transformation and microorganism during composting. The results showed that adding adenosine tri-phosphate (ATP) and nicotinamide adenine dinucleotide (NADH) could enhance the transformation of OC and increase the diversity of microorganism community. Malonic acid (MA) as a competitive inhibitor could decrease the emission of CO 2 by inhibiting the TCA cycle. A structural equation model was established to explore effects of different OC and microorganism on humic acid (HA) concentration during composting. Furthermore, added MA provided an environmental benefit in reducing the greenhouse gas emission for manufacture sustainable products. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Glutamate is the major anaplerotic substrate in the tricarboxylic acid cycle of isolated rumen epithelial and duodenal mucosal cells from beef cattle

    USDA-ARS?s Scientific Manuscript database

    This study aimed to determine the contribution of substrates to tricarboxylic acid (TCA) cycle fluxes in rumen epithelial (REC) and duodenal mucosal (DMC) cells isolated from bulls (n = 6) fed either a 75% forage (HF) or 75% concentrate (HC) diet. In separate incubations, [13C6]glucose, [13C5]glutam...

  12. Modeling the influence of organic acids on soil weathering

    NASA Astrophysics Data System (ADS)

    Lawrence, Corey; Harden, Jennifer; Maher, Kate

    2014-08-01

    Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

  13. Modeling the influence of organic acids on soil weathering

    USGS Publications Warehouse

    Lawrence, Corey R.; Harden, Jennifer W.; Maher, Kate

    2014-01-01

    Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

  14. Conductive Polymer Binder for High-Tap-Density Nanosilicon Material for Lithium-Ion Battery Negative Electrode Application.

    PubMed

    Zhao, Hui; Wei, Yang; Qiao, Ruimin; Zhu, Chenhui; Zheng, Ziyan; Ling, Min; Jia, Zhe; Bai, Ying; Fu, Yanbao; Lei, Jinglei; Song, Xiangyun; Battaglia, Vincent S; Yang, Wanli; Messersmith, Phillip B; Liu, Gao

    2015-12-09

    High-tap-density silicon nanomaterials are highly desirable as anodes for lithium ion batteries, due to their small surface area and minimum first-cycle loss. However, this material poses formidable challenges to polymeric binder design. Binders adhere on to the small surface area to sustain the drastic volume changes during cycling; also the low porosities and small pore size resulting from this material are detrimental to lithium ion transport. This study introduces a new binder, poly(1-pyrenemethyl methacrylate-co-methacrylic acid) (PPyMAA), for a high-tap-density nanosilicon electrode cycled in a stable manner with a first cycle efficiency of 82%-a value that is further improved to 87% when combined with graphite material. Incorporating the MAA acid functionalities does not change the lowest unoccupied molecular orbital (LUMO) features or lower the adhesion performance of the PPy homopolymer. Our single-molecule force microscopy measurement of PPyMAA reveals similar adhesion strength between polymer binder and anode surface when compared with conventional polymer such as homopolyacrylic acid (PAA), while being electronically conductive. The combined conductivity and adhesion afforded by the MAA and pyrene copolymer results in good cycling performance for the high-tap-density Si electrode.

  15. The γ-Glutamyl Cycle in the Choroid Plexus: Its Possible Function in Amino Acid Transport

    PubMed Central

    Tate, Suresh S.; Ross, Leonard L.; Meister, Alton

    1973-01-01

    Various anatomic regions of rabbit brain have been examined for activities of the enzymes of the γ-glutamyl cycle. While these enzyme activities were widely distributed in the brain, they are present in much higher concentrations in the choroid plexus than in other parts of the brain. The activities observed are of about the same order of magnitude as found in the kidney. These observations and other considerations suggest that the γ-glutamyl cycle may play a significant role in the transport of amino acids between blood and cerebrospinal fluid. PMID:4145786

  16. Overexpression of the NADP+-specific isocitrate dehydrogenase gene (icdA) in citric acid-producing Aspergillus niger WU-2223L.

    PubMed

    Kobayashi, Keiichi; Hattori, Takasumi; Hayashi, Rie; Kirimura, Kohtaro

    2014-01-01

    In the tricarboxylic acid (TCA) cycle, NADP(+)-specific isocitrate dehydrogenase (NADP(+)-ICDH) catalyzes oxidative decarboxylation of isocitric acid to form α-ketoglutaric acid with NADP(+) as a cofactor. We constructed an NADP(+)-ICDH gene (icdA)-overexpressing strain (OPI-1) using Aspergillus niger WU-2223L as a host and examined the effects of increase in NADP(+)-ICDH activity on citric acid production. Under citric acid-producing conditions with glucose as the carbon source, the amounts of citric acid produced and glucose consumed by OPI-1 for the 12-d cultivation period decreased by 18.7 and 10.5%, respectively, compared with those by WU-2223L. These results indicate that the amount of citric acid produced by A. niger can be altered with the NADP(+)-ICDH activity. Therefore, NADP(+)-ICDH is an important regulator of citric acid production in the TCA cycle of A. niger. Thus, we propose that the icdA gene is a potentially valuable tool for modulating citric acid production by metabolic engineering.

  17. Formal methods and digital systems validation for airborne systems

    NASA Technical Reports Server (NTRS)

    Rushby, John

    1993-01-01

    This report has been prepared to supplement a forthcoming chapter on formal methods in the FAA Digital Systems Validation Handbook. Its purpose is as follows: to outline the technical basis for formal methods in computer science; to explain the use of formal methods in the specification and verification of software and hardware requirements, designs, and implementations; to identify the benefits, weaknesses, and difficulties in applying these methods to digital systems used on board aircraft; and to suggest factors for consideration when formal methods are offered in support of certification. These latter factors assume the context for software development and assurance described in RTCA document DO-178B, 'Software Considerations in Airborne Systems and Equipment Certification,' Dec. 1992.

  18. Airborne Transducer Integrity under Operational Environment for Structural Health Monitoring

    PubMed Central

    Salmanpour, Mohammad Saleh; Sharif Khodaei, Zahra; Aliabadi, Mohammad Hossein

    2016-01-01

    This paper investigates the robustness of permanently mounted transducers used in airborne structural health monitoring systems, when exposed to the operational environment. Typical airliners operate in a range of conditions, hence, structural health monitoring (SHM) transducer robustness and integrity must be demonstrated for these environments. A set of extreme temperature, altitude and vibration environment test profiles are developed using the existing Radio Technical Commission for Aeronautics (RTCA)/DO-160 test methods. Commercially available transducers and manufactured versions bonded to carbon fibre reinforced polymer (CFRP) composite materials are tested. It was found that the DuraAct transducer is robust to environmental conditions tested, while the other transducer types degrade under the same conditions. PMID:27973450

  19. Reverberation Chamber Uniformity Validation and Radiated Susceptibility Test Procedures for the NASA High Intensity Radiated Fields Laboratory

    NASA Technical Reports Server (NTRS)

    Koppen, Sandra V.; Nguyen, Truong X.; Mielnik, John J.

    2010-01-01

    The NASA Langley Research Center's High Intensity Radiated Fields Laboratory has developed a capability based on the RTCA/DO-160F Section 20 guidelines for radiated electromagnetic susceptibility testing in reverberation chambers. Phase 1 of the test procedure utilizes mode-tuned stirrer techniques and E-field probe measurements to validate chamber uniformity, determines chamber loading effects, and defines a radiated susceptibility test process. The test procedure is segmented into numbered operations that are largely software controlled. This document is intended as a laboratory test reference and includes diagrams of test setups, equipment lists, as well as test results and analysis. Phase 2 of development is discussed.

  20. Unmanned Aviation Systems Models of the Radio Communications Links: Study Results - Appendices Annex 2. Volume 1 and Volume 2

    NASA Technical Reports Server (NTRS)

    Birr, Richard B.; Spencer, Roy; Murray, Jennifer; Lash, Andrew

    2013-01-01

    This report describes the analysis of communications between the Control Station and an Unmanned Aircraft (UA) flying in the National Airspace System (NAS). This work is based on the RTCA SC-203 Operational Services and Environment Description (OSED). The OSED document seeks to characterize the highly different attributes of all UAs navigating the airspace and define their relationship to airspace users, air traffic services, and operating environments of the NAS. One goal of this report is to lead to the development of Minimum Aviation System Performance Standards for Control and Communications. This report takes the nine scenarios found in the OSED and analyzes the communication links.

  1. NAS-Wide Fast-Time Simulation Study for Evaluating Performance of UAS Detect-and-Avoid Alerting and Guidance Systems

    NASA Technical Reports Server (NTRS)

    Lee, Seung Man; Park, Chunki; Cone, Andrew Clayton; Thipphavong, David P.; Santiago, Confesor

    2016-01-01

    This presentation contains the analysis results of NAS-wide fast-time simulations with UAS and VFR traffic for a single day for evaluating the performance of Detect-and-Avoid (DAA) alerting and guidance systems. This purpose of this study was to help refine and validate MOPS alerting and guidance requirements. In this study, we generated plots of all performance metrics that are specified by RTCA SC-228 Minimum Operational Performance Standards (MOPS): 1) to evaluate the sensitivity of alerting parameters on the performance metrics of each DAA alert type: Preventive, Corrective, and Warning alerts and 2) to evaluate the effect of sensor uncertainty on DAA alerting and guidance performance.

  2. Achieving EMC Emissions Compliance for an Aeronautics Power Line Communications System

    NASA Astrophysics Data System (ADS)

    Dominiak, S.; Vos, G.; ter Meer, T.; Widmer, H.

    2012-05-01

    Transmitting data over the power distribution network - Power Line Communications (PLC) -provides an interesting solution to reducing the weight and complexity of wiring networks in commercial aircraft. One of the potential roadblocks for the introduction of this technology is achieving EMC emissions compliance. In this article an overview of the EMC conducted and radiated emissions testing for PLC- enabled aeronautics equipment is presented. Anomalies resulting from chamber resonances leading to discrepancies between the conducted emissions tests and the measured radiated emissions are identified and described. Measurements made according to the current version of the civil aeronautical EMC standard, EUROCAE ED-14F (RTCA DO-160F), show that PLC equipment can achieve full EMC emissions compliance.

  3. Carnosic acid inhibits the growth of ER-negative human breast cancer cells and synergizes with curcumin.

    PubMed

    Einbond, Linda Saxe; Wu, Hsan-Au; Kashiwazaki, Ryota; He, Kan; Roller, Marc; Su, Tao; Wang, Xiaomei; Goldsberry, Sarah

    2012-10-01

    Studies indicate that extracts and purified components, including carnosic acid, from the herb rosemary display significant growth inhibitory activity on a variety of cancers. This paper examines the ability of rosemary/carnosic acid to inhibit the growth of human breast cancer cells and to synergize with curcumin. To do this, we treated human breast cancer cells with rosemary/carnosic acid and assessed effects on cell proliferation, cell cycle distribution, gene expression patterns, activity of the purified Na/K ATPase and combinations with curcumin. Rosemary/carnosic acid potently inhibits proliferation of ER-negative human breast cancer cells and induces G1 cell cycle arrest. Further, carnosic acid is selective for MCF7 cells transfected for Her2, indicating that Her2 may function in its action. To reveal primary effects, we treated ER-negative breast cancer cells with carnosic acid for 6h. At a low dose, 5 μg/ml (15 μM), carnosic acid activated the expression of 3 genes, induced through the presence of antioxidant response elements, including genes involved in glutathione biosynthesis (CYP4F3, GCLC) and transport (SLC7A11). At a higher dose, 20 μg/ml, carnosic acid activated the expression of antioxidant (AKR1C2, TNXRD1, HMOX1) and apoptosis (GDF15, PHLDA1, DDIT3) genes and suppressed the expression of inhibitor of transcription (ID3) and cell cycle (CDKN2C) genes. Carnosic acid exhibits synergy with turmeric/curcumin. These compounds inhibited the activity of the purified Na-K-ATPase which may contribute to this synergy. Rosemary/carnosic acid, alone or combined with curcumin, may be useful to prevent and treat ER-negative breast cancer. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Lipotoxicity in steatohepatitis occurs despite an increase in tricarboxylic acid cycle activity

    PubMed Central

    Patterson, Rainey E.; Kalavalapalli, Srilaxmi; Williams, Caroline M.; Nautiyal, Manisha; Mathew, Justin T.; Martinez, Janie; Reinhard, Mary K.; McDougall, Danielle J.; Rocca, James R.; Yost, Richard A.; Cusi, Kenneth; Garrett, Timothy J.

    2016-01-01

    The hepatic tricarboxylic acid (TCA) cycle is central to integrating macronutrient metabolism and is closely coupled to cellular respiration, free radical generation, and inflammation. Oxidative flux through the TCA cycle is induced during hepatic insulin resistance, in mice and humans with simple steatosis, reflecting early compensatory remodeling of mitochondrial energetics. We hypothesized that progressive severity of hepatic insulin resistance and the onset of nonalcoholic steatohepatitis (NASH) would impair oxidative flux through the hepatic TCA cycle. Mice (C57/BL6) were fed a high-trans-fat high-fructose diet (TFD) for 8 wk to induce simple steatosis and NASH by 24 wk. In vivo fasting hepatic mitochondrial fluxes were determined by 13C-nuclear magnetic resonance (NMR)-based isotopomer analysis. Hepatic metabolic intermediates were quantified using mass spectrometry-based targeted metabolomics. Hepatic triglyceride accumulation and insulin resistance preceded alterations in mitochondrial metabolism, since TCA cycle fluxes remained normal during simple steatosis. However, mice with NASH had a twofold induction (P < 0.05) of mitochondrial fluxes (μmol/min) through the TCA cycle (2.6 ± 0.5 vs. 5.4 ± 0.6), anaplerosis (9.1 ± 1.2 vs. 16.9 ± 2.2), and pyruvate cycling (4.9 ± 1.0 vs. 11.1 ± 1.9) compared with their age-matched controls. Induction of the TCA cycle activity during NASH was concurrent with blunted ketogenesis and accumulation of hepatic diacylglycerols (DAGs), ceramides (Cer), and long-chain acylcarnitines, suggesting inefficient oxidation and disposal of excess free fatty acids (FFA). Sustained induction of mitochondrial TCA cycle failed to prevent accretion of “lipotoxic” metabolites in the liver and could hasten inflammation and the metabolic transition to NASH. PMID:26814015

  5. Spent lead-acid battery recycling in China - A review and sustainable analyses on mass flow of lead.

    PubMed

    Sun, Zhi; Cao, Hongbin; Zhang, Xihua; Lin, Xiao; Zheng, Wenwen; Cao, Guoqing; Sun, Yong; Zhang, Yi

    2017-06-01

    Lead is classified to be one of the top heavy metal pollutants in China. The corresponding environmental issues especially during the management of spent lead-acid battery have already caused significant public awareness and concern. This research gives a brief overview on the recycling situation based on an investigation of the lead industry in China and also the development of technologies for spent lead-acid batteries. The main principles and research focuses of different technologies including pyrometallurgy, hydrometallurgy and greener technologies are summarized and compared. Subsequently, the circulability of lead based on the entire life cycle analyses of lead-acid battery is calculated. By considering different recycling schemes, the recycling situation of spent lead-acid battery in China can be understood semi-quantitatively. According to this research, 30% of the primary lead production can be shut down that the lead production can still ensure consecutive life cycle operation of lead-acid battery, if proper management of the spent lead-acid battery is implemented according to current lead industry situation in China. This research provides a methodology on the view of lead circulability in the whole life cycle of a specific product and is aiming to contribute more quantitative guidelines for efficient organization of lead industry in China. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Engineered Production of Short Chain Fatty Acid in Escherichia coli Using Fatty Acid Synthesis Pathway

    PubMed Central

    Jawed, Kamran; Mattam, Anu Jose; Fatma, Zia; Wajid, Saima; Abdin, Malik Z.; Yazdani, Syed Shams

    2016-01-01

    Short-chain fatty acids (SCFAs), such as butyric acid, have a broad range of applications in chemical and fuel industries. Worldwide demand of sustainable fuels and chemicals has encouraged researchers for microbial synthesis of SCFAs. In this study we compared three thioesterases, i.e., TesAT from Anaerococcus tetradius, TesBF from Bryantella formatexigens and TesBT from Bacteroides thetaiotaomicron, for production of SCFAs in Escherichia coli utilizing native fatty acid synthesis (FASII) pathway and modulated the genetic and bioprocess parameters to improve its yield and productivity. E. coli strain expressing tesBT gene yielded maximum butyric acid titer at 1.46 g L-1, followed by tesBF at 0.85 g L-1 and tesAT at 0.12 g L-1. The titer of butyric acid varied significantly depending upon the plasmid copy number and strain genotype. The modulation of genetic factors that are known to influence long chain fatty acid production, such as deletion of the fadD and fadE that initiates the fatty acid degradation cycle and overexpression of fadR that is a global transcriptional activator of fatty acid biosynthesis and repressor of degradation cycle, did not improve the butyric acid titer significantly. Use of chemical inhibitor cerulenin, which restricts the fatty acid elongation cycle, increased the butyric acid titer by 1.7-fold in case of TesBF, while it had adverse impact in case of TesBT. In vitro enzyme assay indicated that cerulenin also inhibited short chain specific thioesterase, though inhibitory concentration varied according to the type of thioesterase used. Further process optimization followed by fed-batch cultivation under phosphorous limited condition led to production of 14.3 g L-1 butyric acid and 17.5 g L-1 total free fatty acid at 28% of theoretical yield. This study expands our understanding of SCFAs production in E. coli through FASII pathway and highlights role of genetic and process optimization to enhance the desired product. PMID:27466817

  7. Multifunctional co-poly(amic acid): A new binder for Si-based micro-composite anode of lithium-ion battery

    NASA Astrophysics Data System (ADS)

    Lin, Che-Tseng; Huang, Tzu-Yang; Huang, Jau-Jiun; Wu, Nae-Lih; Leung, Man-kit

    2016-10-01

    Multifunctional co-poly(amic acid) (PAmA) containing pyrene and carboxylic acid side-chains is developed as a binder for the recycled kerf-loss Si-Ni-SiC composite anode. The capacity retention performance of the lithium-ion battery can be apparently enhanced. In a long-cycle test of 300 lithiation/delithiation cycles, 79% of capacity retention is achieved. In considering that the recycled kerf-loss Si sample contains 38 wt% inactive micro-sized SiC abrasive particles, the achieved capacity of 648 mAh g-1 is reasonably high in comparison to other reported values. Small anode thickness expansion of 43% is found in a 100 cycle test, reflecting that the use of the PAmA binder can create strong interconnection among the silicon particles, conductive carbons and copper electrode.

  8. An Oral Load of [13C3]Glycerol and Blood NMR Analysis Detect Fatty Acid Esterification, Pentose Phosphate Pathway, and Glycerol Metabolism through the Tricarboxylic Acid Cycle in Human Liver.

    PubMed

    Jin, Eunsook S; Sherry, A Dean; Malloy, Craig R

    2016-09-02

    Drugs and other interventions for high impact hepatic diseases often target biochemical pathways such as gluconeogenesis, lipogenesis, or the metabolic response to oxidative stress. However, traditional liver function tests do not provide quantitative data about these pathways. In this study, we developed a simple method to evaluate these processes by NMR analysis of plasma metabolites. Healthy subjects ingested [U-(13)C3]glycerol, and blood was drawn at multiple times. Each subject completed three visits under differing nutritional states. High resolution (13)C NMR spectra of plasma triacylglycerols and glucose provided new insights into a number of hepatic processes including fatty acid esterification, the pentose phosphate pathway, and gluconeogenesis through the tricarboxylic acid cycle. Fasting stimulated pentose phosphate pathway activity and metabolism of [U-(13)C3]glycerol in the tricarboxylic acid cycle prior to gluconeogenesis or glyceroneogenesis. Fatty acid esterification was transient in the fasted state but continuous under fed conditions. We conclude that a simple NMR analysis of blood metabolites provides an important biomarker of pentose phosphate pathway activity, triacylglycerol synthesis, and flux through anaplerotic pathways in mitochondria of human liver. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Characteristics of NO cycle coupling with urea cycle in non-hyperammonemic carriers of ornithine transcarbamylase deficiency.

    PubMed

    Nagasaka, Hironori; Yorifuji, Tohru; Egawa, Hiroto; Inui, Ayano; Fujisawa, Tomoo; Komatsu, Haruki; Tsukahara, Hirokazu; Uemoto, Shinji; Inomata, Yukihiro

    2013-07-01

    Urea cycle deficient patients with prominent hyperammonemic often exhibit abnormal production of nitric oxide (NO), which reduces vascular tone, along with amino acid abnormalities. However, information related to the metabolic changes in heterozygotes of ornithine transcarbamylase deficiency (OTCD) lacking overt hyperammonemia is quite limited. We examined vascular mediators and amino acids in non-hyperammonemic heterozygotes. Twenty-four heterozygous OTCD adult females without hyperammonemic bouts, defined as non-hyperammonemic carriers, were enrolled. We measured blood amino acids constituting urea cycle and nitric oxide (NO) cycle. Blood concentrations of nitrate/nitrite (NOx) as stable NO-metabolites, asymmetric dimethylarginine (ADMA) inhibiting NO synthesis, and endothelin-1 (ET-1) raising vascular tone were also determined. NOx concentrations were significantly lower in non-hyperammonemic carriers (p < 0.01). However, ADMA and ET-1 levels in this group were comparable to those in the age-matched control group. Arginine and citrulline levels were also significantly lower in non-hyperammonemic carriers than in controls (p < 0.01). Of the 24 non-hyperammonemic carriers, 10 often developed headaches. Their daily NOx and arginine levels were significantly lower than those in headache-free carriers (p < 0.05). In three carriers receiving oral l-arginine, blood NOx concentrations were significantly higher. In two of those three, the occurrence of headaches was decreased. These results suggest that NO cycle coupling with the urea cycle is altered substantially even in non-hyperammonemic OTCD carriers, predisposing them to headaches. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. The structurally related auxin and melatonin tryptophan-derivatives and their roles in Arabidopsis thaliana and in the human malaria parasite Plasmodium falciparum.

    PubMed

    Koyama, Fernanda C; Carvalho, Thais L G; Alves, Eduardo; da Silva, Henrique B; de Azevedo, Mauro F; Hemerly, Adriana S; Garcia, Célia R S

    2013-01-01

    Indole compounds are involved in a range of functions in many organisms. In the human malaria parasite Plasmodium falciparum, melatonin and other tryptophan derivatives are able to modulate its intraerythrocytic cycle, increasing the schizont population as well as parasitemia, likely through ubiquitin-proteasome system (UPS) gene regulation. In plants, melatonin regulates root development, in a similar way to that described for indoleacetic acid, suggesting that melatonin and indoleacetic acid could co-participate in some physiological processes due to structural similarities. In the present work, we evaluate whether the chemical structure similarity found in indoleacetic acid and melatonin can lead to similar effects in Arabidopsis thaliana lateral root formation and P. falciparum cell cycle modulation, as well as in the UPS of gene regulation, by qRT-PCR. Our data show that P. falciparum is not able to respond to indoleacetic acid either in the modulation of the intraerythrocytic cycle or in the gene regulation mediated by the UPS as observed for melatonin. The similarities of these indole compounds are not sufficient to confer synergistic functions in P. falciparum cell cycle modulation, but could interplay in A. thaliana lateral root formation. © 2013 The Author(s) Journal of Eukaryotic Microbiology © 2013 International Society of Protistologists.

  11. Ecophysiological Significance of CO2-Recycling via Crassulacean Acid Metabolism in Talinum calycinum Engelm. (Portulacaceae) 1

    PubMed Central

    Martin, Craig E.; Higley, Michael; Wang, Wei-Zhong

    1988-01-01

    High levels of variability in gas exchange characteristics and degree of CAM-cycling were found in the same and different individuals of Talinum calycinum Engelm. collected from rock outcrops in Missouri. Differences in CO2 assimilation were mostly correlated with differences in shoot conductance to CO2 not shoot internal CO2 concentration. As found previously, CAM acid fluctuations were evident in well-watered plants exhibiting C3 gas exchange patterns (CAM-cycling) and also in drought-stressed plants with stomata closed, or nearly so, day and night (CAM-idling). Drought stress also resulted in rapid stomatal closure, conserving water during droughts. Maximal CO2 uptake rates occurred below 35°C; higher temperatures induced decreases in CO2 assimilation and conductance while shoot internal CO2 concentrations remained similar. Plant water-use-efficiency was severely curtailed at temperatures above 30°C. Tissue acid fluctuations were the result of changes in malic acid concentrations. Calculations of the amount of water potentially conserved by CAM-cycling yielded values of approximately 5 to 44% of daytime water loss. Thus, CAM-cycling may be an important adaptation minimizing water loss by perennial succulents growing in shallow soil on rock outcrops. PMID:16665946

  12. Metabolomics and transcriptomics profiles reveal the dysregulation of the tricarboxylic acid cycle and related mechanisms in prostate cancer.

    PubMed

    Shao, Yaping; Ye, Guozhu; Ren, Shancheng; Piao, Hai-Long; Zhao, Xinjie; Lu, Xin; Wang, Fubo; Ma, Wang; Li, Jia; Yin, Peiyuan; Xia, Tian; Xu, Chuanliang; Yu, Jane J; Sun, Yinghao; Xu, Guowang

    2018-07-15

    Genetic alterations drive metabolic reprograming to meet increased biosynthetic precursor and energy demands for cancer cell proliferation and survival in unfavorable environments. A systematic study of gene-metabolite regulatory networks and metabolic dysregulation should reveal the molecular mechanisms underlying prostate cancer (PCa) pathogenesis. Herein, we performed gas chromatography-mass spectrometry (GC-MS)-based metabolomics and RNA-seq analyses in prostate tumors and matched adjacent normal tissues (ANTs) to elucidate the molecular alterations and potential underlying regulatory mechanisms in PCa. Significant accumulation of metabolic intermediates and enrichment of genes in the tricarboxylic acid (TCA) cycle were observed in tumor tissues, indicating TCA cycle hyperactivation in PCa tissues. In addition, the levels of fumarate and malate were highly correlated with the Gleason score, tumor stage and expression of genes encoding related enzymes and were significantly related to the expression of genes involved in branched chain amino acid degradation. Using an integrated omics approach, we further revealed the potential anaplerotic routes from pyruvate, glutamine catabolism and branched chain amino acid (BCAA) degradation contributing to replenishing metabolites for TCA cycle. Integrated omics techniques enable the performance of network-based analyses to gain a comprehensive and in-depth understanding of PCa pathophysiology and may facilitate the development of new and effective therapeutic strategies. © 2018 UICC.

  13. Citric acid application for denitrification process support in biofilm reactor.

    PubMed

    Mielcarek, Artur; Rodziewicz, Joanna; Janczukowicz, Wojciech; Dabrowska, Dorota; Ciesielski, Slawomir; Thornton, Arthur; Struk-Sokołowska, Joanna

    2017-03-01

    The study demonstrated that citric acid, as an organic carbon source, can improve denitrification in Anaerobic Sequencing Batch Biofilm Reactor (AnSBBR). The consumption rate of the organic substrate and the denitrification rate were lower during the period of the reactor's acclimatization (cycles 1-60; 71.5 mgCOD L -1  h -1 and 17.81 mgN L -1  h -1 , respectively) than under the steady state conditions (cycles 61-180; 143.8 mgCOD L -1  h -1 and 24.38 mgN L -1  h -1 ). The biomass yield coefficient reached 0.04 ± 0.02 mgTSS· mgCOD re -1 (0.22 ± 0.09 mgTSS mgN re -1 ). Observations revealed the diversified microbiological ecology of the denitrifying bacteria. Citric acid was used mainly by bacteria representing the Trichoccocus genus, which represented above 40% of the sample during the first phase of the process (cycles 1-60). In the second phase (cycles 61-180) the microorganisms the genera that consumed the acetate and formate, as the result of citric acid decomposition were Propionibacterium (5.74%), Agrobacterium (5.23%), Flavobacterium (1.32%), Sphaerotilus (1.35%), Erysipelothrix (1.08%). Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Trapping by amylose of the aliphatic chain grafted onto chlorogenic acid: importance of the graft position.

    PubMed

    Le-Bail, P; Lorentz, C; Pencreac'h, G; Soultani-Vigneron, S; Pontoire, B; López Giraldo, L J; Villeneuve, P; Hendrickx, J; Tran, V

    2015-03-06

    5-Caffeoylquinic acid (chlorogenic acid), is classified in acid-phenols family and as polyphenolic compounds it possesses antioxidant activity. The oxydative modification of chlorogenic acid in foods may lead to alteration of their qualities; to counteract these degradation effects, molecular encapsulation was used to protect chlorogenic acid. Amylose can interact strongly with a number of small molecules, including lipids. In order to enable chlorogenic acid complexation by amylose, a C16 aliphatic chain was previously grafted onto the cycle of quinic acid. This work showed that for the two lipophilic derivatives of chlorogenic acid: hexadecyl chlorogenate obtained by alkylation and 3-O-palmitoyl chlorogenic acid obtained by acylation; only the 3-O-palmitoyl chlorogenic acid complexed amylose. The chlorogenic acid derivatives were studied by X-ray diffraction, differential scanning calorimetry and NMR to elucidate the interaction. By comparing the results with previous work on the complexation of amylose by 4-O-palmitoyl chlorogenic acid, the importance of the aliphatic chain position on the cycle of the quinic acid is clearly highlighted. A study in molecular modeling helped to understand the difference in behavior relative to amylose of these three derivatives of chlorogenic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Unsuspected task for an old team: succinate, fumarate and other Krebs cycle acids in metabolic remodeling.

    PubMed

    Bénit, Paule; Letouzé, Eric; Rak, Malgorzata; Aubry, Laetitia; Burnichon, Nelly; Favier, Judith; Gimenez-Roqueplo, Anne-Paule; Rustin, Pierre

    2014-08-01

    Seventy years from the formalization of the Krebs cycle as the central metabolic turntable sustaining the cell respiratory process, key functions of several of its intermediates, especially succinate and fumarate, have been recently uncovered. The presumably immutable organization of the cycle has been challenged by a number of observations, and the variable subcellular location of a number of its constitutive protein components is now well recognized, although yet unexplained. Nonetheless, the most striking observations have been made in the recent period while investigating human diseases, especially a set of specific cancers, revealing the crucial role of Krebs cycle intermediates as factors affecting genes methylation and thus cell remodeling. We review here the recent advances and persisting incognita about the role of Krebs cycle acids in diverse aspects of cellular life and human pathology. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Development of a lead-acid battery for a hybrid electric vehicle

    NASA Astrophysics Data System (ADS)

    Cooper, A.

    In September 2000, a project reliable, highly optimized lead-acid battery (RHOLAB) started under the UK Foresight Vehicle Programme with the objective of developing an optimized lead-acid battery solution for hybrid electric vehicles. The work is based on a novel, individual, spirally-wound valve-regulated lead-acid 2 V cell optimized for HEV use and low variability. This cell is being used as a building block for the development of a complete battery pack that is managed at the cell level. Following bench testing, this battery pack is to be thoroughly evaluated by substituting it for the Ni-MH pack in a Honda Insight. The RHOLAB cell is based on the 8 Ah Hawker Cyclon cell which has been modified to have current take-off at both ends—the dual-tab design. In addition, a variant has been produced with modified cell chemistry to help deal with problems that can occur when these valve-regulated lead-acid battery (VRLA) cells operate in a partial-state-of-charge condition. The cells have been cycled to a specially formulated test cycle based on real vehicle data derived from testing the Honda Insight on the various test tracks at the Millbrook Proving Grounds in the UK. These cycling tests have shown that the lead-acid pack can be successfully cycled when subjected to the high current demands from the vehicle, which have been measured at up to 15 C on discharge and 8 C during regenerative recharging, and cycle life is looking very promising under this arduous test regime. Concurrent with this work, battery development has been taking place. It was decided early on to develop the 144 V battery as four 36 V modules. Data collection and control has been built-in and special steps taken to minimize the problems of interconnect in this complex system. Development of the battery modules is now at an advanced stage. The project plan then allows for extensive testing of the vehicle with its lead-acid battery at Millbrook so it can be compared with the benchmark tests which have already been carried out on the vehicle with its Ni-MH batteries.

  17. Regulation of Primary Metabolism in Response to Low Oxygen Availability as Revealed by Carbon and Nitrogen Isotope Redistribution.

    PubMed

    António, Carla; Päpke, Carola; Rocha, Marcio; Diab, Houssein; Limami, Anis M; Obata, Toshihiro; Fernie, Alisdair R; van Dongen, Joost T

    2016-01-01

    Based on enzyme activity assays and metabolic responses to waterlogging of the legume Lotus japonicus, it was previously suggested that, during hypoxia, the tricarboxylic acid cycle switches to a noncyclic operation mode. Hypotheses were postulated to explain the alternative metabolic pathways involved, but as yet, a direct analysis of the relative redistribution of label through the corresponding pathways was not made. Here, we describe the use of stable isotope-labeling experiments for studying metabolism under hypoxia using wild-type roots of the crop legume soybean (Glycine max). [(13)C]Pyruvate labeling was performed to compare metabolism through the tricarboxylic acid cycle, fermentation, alanine metabolism, and the γ-aminobutyric acid shunt, while [(13)C]glutamate and [(15)N]ammonium labeling were performed to address the metabolism via glutamate to succinate. Following these labelings, the time course for the redistribution of the (13)C/(15)N label throughout the metabolic network was evaluated with gas chromatography-time of flight-mass spectrometry. Our combined labeling data suggest the inhibition of the tricarboxylic acid cycle enzyme succinate dehydrogenase, also known as complex II of the mitochondrial electron transport chain, providing support for the bifurcation of the cycle and the down-regulation of the rate of respiration measured during hypoxic stress. Moreover, up-regulation of the γ-aminobutyric acid shunt and alanine metabolism explained the accumulation of succinate and alanine during hypoxia. © 2016 American Society of Plant Biologists. All Rights Reserved.

  18. DWPF SIMULANT CPC STUDIES FOR SB7B

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

    Koopman, D.

    2011-11-01

    Lab-scale DWPF simulations of Sludge Batch 7b (SB7b) processing were performed. Testing was performed at the Savannah River National Laboratory - Aiken County Technology Laboratory (SRNL-ACTL). The primary goal of the simulations was to define a likely operating window for acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT). In addition, the testing established conditions for the SRNL Shielded Cells qualification simulation of SB7b-Tank 40 blend, supported validation of the current glass redox model, and validated the coupled process flowsheet at the nominal acid stoichiometry. An acid window of 105-140% by the Koopman minimum acid (KMA) equation (107-142%more » DWPF Hsu equation) worked for the sludge-only flowsheet. Nitrite was present in the SRAT product for the 105% KMA run at 366 mg/kg, while SME cycle hydrogen reached 94% of the DWPF Slurry Mix Evaporator (SME) cycle limit in the 140% KMA run. The window was determined for sludge with added caustic (0.28M additional base, or roughly 12,000 gallons 50% NaOH to 820,000 gallons waste slurry). A suitable processing window appears to be 107-130% DWPF acid equation for sludge-only processing allowing some conservatism for the mapping of lab-scale simulant data to full-scale real waste processing including potentially non-conservative noble metal and mercury concentrations. This window should be usable with or without the addition of up to 7,000 gallons of caustic to the batch. The window could potentially be wider if caustic is not added to SB7b. It is recommended that DWPF begin processing SB7b at 115% stoichiometry using the current DWPF equation. The factor could be increased if necessary, but changes should be made with caution and in small increments. DWPF should not concentrate past 48 wt.% total solids in the SME cycle if moderate hydrogen generation is occurring simultaneously. The coupled flowsheet simulation made more hydrogen in the SRAT and SME cycles than the sludge-only run with the same acid stoichiometric factor. The slow acid addition in MCU seemed to alter the reactions that consumed the small excess acid present such that hydrogen generation was promoted relative to sludge-only processing. The coupled test reached higher wt.% total solids, and this likely contributed to the SME cycle hydrogen limit being exceeded at 110% KMA. It is clear from the trends in the SME processing GC data, however, that the frit slurry formic acid contributed to driving the hydrogen generation rate above the SME cycle limit. Hydrogen generation rates after the second frit addition generally exceeded those after the first frit addition. SRAT formate loss increased with increasing acid stoichiometry (15% to 35%). A substantial nitrate gain which was observed to have occurred after acid addition (and nitrite destruction) was reversed to a net nitrate loss in runs with higher acid stoichiometry (nitrate in SRAT product less than sum of sludge nitrate and added nitric acid). Increased ammonium ion formation was also indicated in the runs with nitrate loss. Oxalate loss on the order 20% was indicated in three of the four acid stoichiometry runs and in the coupled flowsheet run. The minimum acid stoichiometry run had no indicated loss. The losses were of the same order as the official analytical uncertainty of the oxalate concentration measurement, but were not randomly distributed about zero loss, so some actual loss was likely occurring. Based on the entire set of SB7b test data, it is recommended that DWPF avoid concentrating additional sludge solids in single SRAT batches to limit the concentrations of noble metals to SB7a processing levels (on a grams noble metal per SRAT batch basis). It is also recommended that DWPF drop the formic acid addition that accompanies the process frit 418 additions, since SME cycle data showed considerable catalytic activity for hydrogen generation from this additional acid (about 5% increase in stoichiometry occurred from the frit formic acid). Frit 418 also does not appear to need formic acid addition to prevent gel formation in the frit slurry. Simulant processing was successful using 100 ppm of 747 antifoam added prior to nitric acid instead of 200 ppm. This is a potential area for DWPF to cut antifoam usage in any future test program. An additional 100 ppm was added before formic acid addition. Foaming during formic acid addition was not observed. No build-up of oily or waxy material was observed in the off-gas equipment. Lab-scale mercury stripping behavior was similar to SB6 and SB7a. More mercury was unaccounted for as the acid stoichiometry increased.« less

  19. FabQ, a Dual-Function Dehydratase/Isomerase, Circumvents the Last Step of the Classical Fatty Acid Synthesis Cycle

    PubMed Central

    Bi, Hongkai; Wang, Haihong; Cronan, John E.

    2015-01-01

    SUMMARY In the classical anaerobic pathway of unsaturated fatty acid biosynthesis, that of Escherichia coli, the double bond is introduced into the growing acyl chain by the FabA dehydratase/isomerase. Another dehydratase, FabZ, functions in the chain elongation cycle. In contrast, Aerococcus viridans has only a single FabA/FabZ homolog we designate FabQ. FabQ can not only replace the function of E. coli FabZ in vivo, but it also catalyzes the isomerization required for unsaturated fatty acid biosynthesis. Most strikingly, FabQ in combination with E. coli FabB imparts the surprising ability to bypass reduction of the trans-2-acyl-ACP intermediates of classical fatty acid synthesis. FabQ allows elongation by progressive isomerization reactions to form the polyunsaturated fatty acid, 3-hydroxy-cis-5, 7-hexadecadienoic acid, both in vitro and in vivo. FabQ therefore provides a potential pathway for bacterial synthesis of polyunsaturated fatty acids. PMID:23972938

  20. Year-round records of gas and particulate carboxylic acids (formate and acetate) in the boundary layer at Dumont d'Urville (coastal Antarctica): Production of carboxylic acids from biogenic NMHC emissions from the Antarctic ocean

    NASA Astrophysics Data System (ADS)

    Legrand, M.; Preunkert, S.; Jourdain, B.

    2003-04-01

    Multiple year-round concentrations of acetic and formic acids were measured both in gas and aerosol phases at Dumont d'Urville (DDU, a coastal Antarctic site: 66^o40'S, 140^o01'E) by using mist chamber and aerosol filter sampling. Aerosol levels of the 2 carboxylates range from less than one ng m-3 in winter to 5--10 ng m-3 in summer. Comparison with gas phase concentrations shows that almost 99% of the 2 carboxylic acids are present in the gas phase. Concentrations of formic acid in the gas phase are minima in June--July (70 ng m-3) and increase regularly towards summer months when levels reach ˜400 ng m-3. Concentrations of acetic acid in the gas phase exhibit a more well-marked seasonal cycle with values remaining close to 50 ng m-3 from April to October and strongly increase during summer months (mean value of 800 ng m-3). Such a strong seasonal cycle of carboxylic acids in the high southern latitude marine boundary layer displays with observations made at numerous continental sites where a more weak seasonality is generally observed. It is suggested that carboxylic acids present at DDU mainly originate from biogenic emissions from the Antarctic ocean which are expected to closely follow annual cycle of the sea ice extent and solar radiation, affecting in particular photochemical production of alkenes from dissolved organic carbon released from phytoplancton. Summer levels of carboxylic acids are discussed in terms of air-sea fluxes of NMHCs and photochemical production of carboxylic acids from ozone-alkene reactions and HO_2 reaction with peroxyacetal radical in these poor NOx environments.

  1. Contribution of the tricarboxylic acid (TCA) cycle and the glyoxylate shunt in Saccharomyces cerevisiae to succinic acid production during dough fermentation.

    PubMed

    Rezaei, Mohammad N; Aslankoohi, Elham; Verstrepen, Kevin J; Courtin, Christophe M

    2015-07-02

    Succinic acid produced by yeast during bread dough fermentation can significantly affect the rheological properties of the dough. By introducing mutations in the model S288C yeast strain, we show that the oxidative pathway of the TCA cycle and the glyoxylate shunt contribute significantly to succinic acid production during dough fermentation. More specifically, deletion of ACO1 and double deletion of ACO1 and ICL1 resulted in a 36 and 77% decrease in succinic acid levels in fermented dough, respectively. Similarly, double deletion of IDH1 and IDP1 decreased succinic acid production by 85%, while also affecting the fermentation rate. By contrast, double deletion of SDH1 and SDH2 resulted in a two-fold higher succinic acid accumulation compared to the wild-type. Deletion of fumarate reductase activity (FRD1 and OSM1) in the reductive pathway of the TCA cycle did not affect the fermentation rate and succinic acid production. The changes in the levels of succinic acid produced by mutants Δidh1Δidp1 (low level) and Δsdh1Δsdh2 (high level) in fermented dough only resulted in small pH differences, reflecting the buffering capacity of dough at a pH of around 5.1. Moreover, Rheofermentometer analysis using these mutants revealed no difference in maximum dough height and gas retention capacity with the dough prepared with S288C. The impact of the changed succinic acid profile on the organoleptic or antimicrobial properties of bread remains to be demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Lead-acid batteries in solar photovoltaic power systems for marine aids to navigation. Final report

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

    Trenchard, S.E.

    1981-10-01

    Since 1974, the U.S. Coast Guard has been testing lead-acid batteries in solar photovoltaic-powered systems for aids to navigation. Three types of lead-acid batteries, distinguished by the composition of their grid material, have been tested: lead-antimony grid, lead-calcium grid, and pure-lead grid. This report contains a comparison of the charging characteristics and the charge-discharge cycling behavior of each grid type. All types were remarkably similar qualitatively in their daily as well as annual cycling behavior but the significance of the quantitative differences offer distinctive tradeoffs. This report presents models for water usage, depth-of-discharge, and post-cycle capacity for various levels ofmore » voltage regulation. Based on the post-cycle capacity tests, the effect of grid strength, grid thickness, and operating conditions on life expectancy are presented. A final discussion presents the results of a field deployment of solar photovoltaic-powered aids to navigation in the Miami, Florida area. Potential solutions to the battery terminal corrosion and bird guano problems observed are discussed.« less

  3. The origin of intermediary metabolism

    NASA Technical Reports Server (NTRS)

    Morowitz, H. J.; Kostelnik, J. D.; Yang, J.; Cody, G. D.

    2000-01-01

    The core of intermediary metabolism in autotrophs is the citric acid cycle. In a certain group of chemoautotrophs, the reductive citric acid cycle is an engine of synthesis, taking in CO(2) and synthesizing the molecules of the cycle. We have examined the chemistry of a model system of C, H, and O that starts with carbon dioxide and reductants and uses redox couples as the energy source. To inquire into the reaction networks that might emerge, we start with the largest available database of organic molecules, Beilstein on-line, and prune by a set of physical and chemical constraints applicable to the model system. From the 3.5 million entries in Beilstein we emerge with 153 molecules that contain all 11 members of the reductive citric acid cycle. A small number of selection rules generates a very constrained subset, suggesting that this is the type of reaction model that will prove useful in the study of biogenesis. The model indicates that the metabolism shown in the universal chart of pathways may be central to the origin of life, is emergent from organic chemistry, and may be unique.

  4. Studies of thermochemical water-splitting cycles

    NASA Technical Reports Server (NTRS)

    Remick, R. J.; Foh, S. E.

    1980-01-01

    Higher temperatures and more isothermal heat profiles of solar heat sources are developed. The metal oxide metal sulfate class of cycles were suited for solar heat sources. Electrochemical oxidation of SO2 and thermochemical reactions are presented. Electrolytic oxidation of sulfur dioxide in dilute sulfuric acid solutions were appropriate for metal oxide metal sulfate cycles. The cell voltage at workable current densities required for the oxidation of SO2 was critical to the efficient operation of any metal oxide metal sulfate cycle. A sulfur dioxide depolarized electrolysis cell for the splitting of water via optimization of the anode reaction is discussed. Sulfuric acid concentrations of 30 to 35 weight percent are preferred. Platinized platinum or smooth platinum gave the best anode kinetics at a given potential of the five materials examined.

  5. Food-web complexity across hydrothermal vents on the Azores triple junction

    NASA Astrophysics Data System (ADS)

    Portail, Marie; Brandily, Christophe; Cathalot, Cécile; Colaço, Ana; Gélinas, Yves; Husson, Bérengère; Sarradin, Pierre-Marie; Sarrazin, Jozée

    2018-01-01

    The assessment and comparison of food webs across various hydrothermal vent sites can enhance our understanding of ecological processes involved in the structure and function of biodiversity. The Menez Gwen, Lucky Strike and Rainbow vent fields are located on the Azores triple junction of the Mid-Atlantic Ridge. These fields have distinct depths (from 850 to 2320 m) and geological contexts (basaltic and ultramafic), but share similar faunal assemblages defined by the presence of foundation species that include Bathymodiolus azoricus, alvinocarid shrimp and gastropods. We compared the food webs of 13 faunal assemblages at these three sites using carbon and nitrogen stable isotope analyses (SIA). Results showed that photosynthesis-derived organic matter is a negligible basal source for vent food webs, at all depths. The contribution of methanotrophy versus autotrophy based on Calvin-Benson-Bassham (CBB) or reductive tricarboxylic acid (rTCA) cycles varied between and within vent fields according to the concentrations of reduced compounds (e.g. CH4, H2S). Species that were common to vent fields showed high trophic flexibility, suggesting weak trophic links to the metabolism of chemosynthetic primary producers. At the community level, a comparison of SIA-derived metrics between mussel assemblages from two vent fields (Menez Gwen & Lucky Strike) showed that the functional structure of food webs was highly similar in terms of basal niche diversification, functional specialization and redundancy. Coupling SIA to functional trait approaches included more variability within the analyses, but the functional structures were still highly comparable. These results suggest that despite variable environmental conditions (physico-chemical factors and basal sources) and faunal community structure, functional complexity remained relatively constant among mussel assemblages. This functional similarity may be favoured by the propensity of species to adapt to fluid variations and practise trophic flexibility. Furthermore, the different pools of species at vent fields may play similar functions in the community such as the change in composition does not affect the overall functional structure. Finally, the absence of a relationship between the functional structure and taxonomic diversity as well as the high overlap between species' isotopic niches within communities indicates that co-occuring species may have redundant functions. Therefore, the addition of species within in a functional group does not necessarily lead to more complexity. Overall, this study highlights the complexity of food webs within chemosynthetic communities and emphasizes the need to better characterize species' ecological niches and biotic interactions.

  6. An integrated, self-contained microfluidic cassette for isolation, amplification, and detection of nucleic acids.

    PubMed

    Chen, Dafeng; Mauk, Michael; Qiu, Xianbo; Liu, Changchun; Kim, Jitae; Ramprasad, Sudhir; Ongagna, Serge; Abrams, William R; Malamud, Daniel; Corstjens, Paul L A M; Bau, Haim H

    2010-08-01

    A self-contained, integrated, disposable, sample-to-answer, polycarbonate microfluidic cassette for nucleic acid-based detection of pathogens at the point of care was designed, constructed, and tested. The cassette comprises on-chip sample lysis, nucleic acid isolation, enzymatic amplification (polymerase chain reaction and, when needed, reverse transcription), amplicon labeling, and detection. On-chip pouches and valves facilitate fluid flow control. All the liquids and dry reagents needed for the various reactions are pre-stored in the cassette. The liquid reagents are stored in flexible pouches formed on the chip surface. Dry (RT-)PCR reagents are pre-stored in the thermal cycling, reaction chamber. The process operations include sample introduction; lysis of cells and viruses; solid-phase extraction, concentration, and purification of nucleic acids from the lysate; elution of the nucleic acids into a thermal cycling chamber and mixing with pre-stored (RT-)PCR dry reagents; thermal cycling; and detection. The PCR amplicons are labeled with digoxigenin and biotin and transmitted onto a lateral flow strip, where the target analytes bind to a test line consisting of immobilized avidin-D. The immobilized nucleic acids are labeled with up-converting phosphor (UCP) reporter particles. The operation of the cassette is automatically controlled by an analyzer that provides pouch and valve actuation with electrical motors and heating for the thermal cycling. The functionality of the device is demonstrated by detecting the presence of bacterial B.Cereus, viral armored RNA HIV, and HIV I virus in saliva samples. The cassette and actuator described here can be used to detect other diseases as well as the presence of bacterial and viral pathogens in the water supply and other fluids.

  7. Genomic Foundation of Starch-to-Lipid Switch in Oleaginous Chlorella spp.1

    PubMed Central

    Fan, Jianhua; Ning, Kang; Zeng, Xiaowei; Luo, Yuanchan; Wang, Dongmei; Hu, Jianqiang; Li, Jing; Xu, Hui; Huang, Jianke; Wan, Minxi; Wang, Weiliang; Zhang, Daojing; Shen, Guomin; Run, Conglin; Liao, Junjie; Fang, Lei; Huang, Shi; Jing, Xiaoyan; Su, Xiaoquan; Wang, Anhui; Bai, Lili; Hu, Zanmin; Xu, Jian; Li, Yuanguang

    2015-01-01

    The ability to rapidly switch the intracellular energy storage form from starch to lipids is an advantageous trait for microalgae feedstock. To probe this mechanism, we sequenced the 56.8-Mbp genome of Chlorella pyrenoidosa FACHB-9, an industrial production strain for protein, starch, and lipids. The genome exhibits positive selection and gene family expansion in lipid and carbohydrate metabolism and genes related to cell cycle and stress response. Moreover, 10 lipid metabolism genes might be originated from bacteria via horizontal gene transfer. Transcriptomic dynamics tracked via messenger RNA sequencing over six time points during metabolic switch from starch-rich heterotrophy to lipid-rich photoautotrophy revealed that under heterotrophy, genes most strongly expressed were from the tricarboxylic acid cycle, respiratory chain, oxidative phosphorylation, gluconeogenesis, glyoxylate cycle, and amino acid metabolisms, whereas those most down-regulated were from fatty acid and oxidative pentose phosphate metabolism. The shift from heterotrophy into photoautotrophy highlights up-regulation of genes from carbon fixation, photosynthesis, fatty acid biosynthesis, the oxidative pentose phosphate pathway, and starch catabolism, which resulted in a marked redirection of metabolism, where the primary carbon source of glycine is no longer supplied to cell building blocks by the tricarboxylic acid cycle and gluconeogenesis, whereas carbon skeletons from photosynthesis and starch degradation may be directly channeled into fatty acid and protein biosynthesis. By establishing the first genetic transformation in industrial oleaginous C. pyrenoidosa, we further showed that overexpression of an NAD(H) kinase from Arabidopsis (Arabidopsis thaliana) increased cellular lipid content by 110.4%, yet without reducing growth rate. These findings provide a foundation for exploiting the metabolic switch in microalgae for improved photosynthetic production of food and fuels. PMID:26486592

  8. Enzymes in Glycolysis and the Citric Acid Cycle in the Yeast and Mycelial Forms of Paracoccidioides brasiliensis

    PubMed Central

    Kanetsuna, Fuminori; Carbonell, Luis M.

    1966-01-01

    Kanetsuna, Fuminori (Instituto Venezolano de Investigaciones Cientificas, Caracas, Venezuela), and Luis M. Carbonell. Enzymes in glycolysis and the citric acid cycle in the yeast and mycelial forms of Paracoccidioides brasiliensis. J. Bacteriol. 92:1315–1320. 1966.—Enzymatic activities in glycolysis, the hexose monophosphate shunt, and the citric acid cycle in cell-free extracts of the yeast and mycelial forms of Paracoccidioides brasiliensis were examined comparatively. Both forms have the enzymes of these pathways. Activities of glucose-6-phosphate dehydrogenase and malic dehydrogenase of the mycelial form were higher than those of the yeast form. Another 15 enzymatic activities of the mycelial form were lower than those of the yeast form. The activity of glyceraldehyde-3-phosphate dehydrogenase showed the most marked difference between the two forms, its activity in the mycelial form being about 20% of that in the yeast form. PMID:5924267

  9. Formation of trans fatty acids during the frying of chicken fillet in corn oil.

    PubMed

    Yang, Meiyan; Yang, Ying; Nie, Shaoping; Xie, Mingyong; Chen, Feng; Luo, Pengju George

    2014-05-01

    To assess effects of heated edible oils on intake of trans fatty acids (TFAs); the formation of TFAs in cooking conditions was investigated by a frying system model, in which chicken fillet was fried in a commercial corn oil at 170 °C, for 12 frying cycles. The main TFAs detected in chicken fillet were trans C18:2 fatty acids (FAs) and trans C18:3 FAs, which exhibited no significant differences among the frying cycles. Besides, the content of trans C18:1 FAs were very low in all samples on different frying cycles. The intake of TFAs was estimated to be 0.06 g/100 g when chicken fillet fried in this process was consumed. These results suggest that an ordinary frying process upon a commercial corn oil has little impact on the daily TFAs intake.

  10. BAG3 promotes the phenotypic transformation of primary rat vascular smooth muscle cells via TRAIL.

    PubMed

    Fu, Yao; Chang, Ye; Chen, Shuang; Li, Yuan; Chen, Yintao; Sun, Guozhe; Yu, Shasha; Ye, Ning; Li, Chao; Sun, Yingxian

    2018-05-01

    Under normal physiological condition, the mature vascular smooth muscle cells (VSMCs) show differentiated phenotype. In response to various environmental stimuluses, VSMCs convert from the differentiated phenotype to dedifferentiated phenotype characterized by the increased ability of proliferation/migration and the reduction of contractile ability. The phenotypic transformation of VSMCs played an important role in atherosclerosis. Both Bcl-2-associated athanogene 3 (BAG3) and tumor necrosis factor-related apopt-osis inducing ligand (TRAIL) involved in apoptosis. The relationship between BAG3 and TRAIL and their effects the proliferation and migration in VSMCs are rarely reported. This study investigated the effects of BAG3 on the phenotypic modulation and the potential underlying mechanisms in primary rat VSMCs. Primary rat VSMCs were extracted and cultured in vitro. Cell proliferation was detected by cell counting, real-time cell analyzer (RTCA) and EdU incorporation. Cell migration was detected by wound healing, Transwell and RTCA. BAG3 and TRAIL were detected using real-time PCR and western blotting and the secreted proteins in the cultured media by dot blot. The expression of BAG3 increased with continued passages in cultured primary VSMCs. BAG3 promoted the proliferation and migration of primary rat VSMC in a time-dependent manner. BAG3 significantly increased the expression of TRAIL while had no effects on its receptors. TRAIL knockdown or blocking by neutralizing antibody inhibited the proliferation of VSMCs induced by BAG3. TRAIL knockdown exerted no obvious influence on the migration of VSMCs. Based on this study, we report for the first time that BAG3 was expressed in cultured primary rat VSMCs and the expression of BAG3 increased with continued passages. Furthermore, BAG3 promoted the proliferation of VSMCs via increasing the expression of TRAIL. In addition, we also demonstrated that BAG3 promoted the migration of VSMCs independent of TRAIL upregulation.

  11. Cerium dioxide (CeO2) nanoparticles decrease arsenite (As(III)) cytotoxicity to 16HBE14o- human bronchial epithelial cells.

    PubMed

    Zeng, Chao; Nguyen, Chi; Boitano, Scott; Field, Jim A; Shadman, Farhang; Sierra-Alvarez, Reyes

    2018-07-01

    The production and application of engineered nanoparticles (NPs) are increasing in demand with the rapid development of nanotechnology. However, there are concerns that some of these novel materials could lead to emerging environmental and health problems. Some NPs are able to facilitate the transport of contaminants into cells/organisms via a "Trojan Horse" effect which enhances the toxicity of the adsorbed materials. In this work, we evaluated the toxicity of arsenite (As(III)) adsorbed onto cerium dioxide (CeO 2 ) NPs to human bronchial epithelial cells (16HBE14o-) using the xCELLigence real time cell analyzing system (RTCA). Application of 0.5 mg/L As(III) resulted in 81.3% reduction of cell index (CI, an RTCA measure of cell toxicity) over 48 h when compared to control cells exposed to medium lacking As(III). However, when the cells were exposed to 0.5 mg/L As(III) in the presence of CeO 2 NPs (250 mg/L), the CI was only reduced by 12.9% compared to the control. The CeO 2 NPs had a high capacity for As(III) adsorption (20.2 mg/g CeO 2 ) in the bioassay medium, effectively reducing dissolved As(III) in the aqueous solution and resulting in reduced toxicity. Transmission electron microscopy was used to study the transport of CeO 2 NPs into 16HBE14o- cells. NP uptake via engulfment was observed and the internalized NPs accumulated in vesicles. The results demonstrate that dissolved As(III) in the aqueous solution was the decisive factor controlling As(III) toxicity of 16HBE14o- cells, and that CeO 2 NPs effectively reduced available As(III) through adsorption. These data emphasize the evaluation of mixtures when assaying toxicity. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. In Folio Respiratory Fluxomics Revealed by 13C Isotopic Labeling and H/D Isotope Effects Highlight the Noncyclic Nature of the Tricarboxylic Acid “Cycle” in Illuminated Leaves1[W

    PubMed Central

    Tcherkez, Guillaume; Mahé, Aline; Gauthier, Paul; Mauve, Caroline; Gout, Elizabeth; Bligny, Richard; Cornic, Gabriel; Hodges, Michael

    2009-01-01

    While the possible importance of the tricarboxylic acid (TCA) cycle reactions for leaf photosynthesis operation has been recognized, many uncertainties remain on whether TCA cycle biochemistry is similar in the light compared with the dark. It is widely accepted that leaf day respiration and the metabolic commitment to TCA decarboxylation are down-regulated in illuminated leaves. However, the metabolic basis (i.e. the limiting steps involved in such a down-regulation) is not well known. Here, we investigated the in vivo metabolic fluxes of individual reactions of the TCA cycle by developing two isotopic methods, 13C tracing and fluxomics and the use of H/D isotope effects, with Xanthium strumarium leaves. We provide evidence that the TCA “cycle” does not work in the forward direction like a proper cycle but, rather, operates in both the reverse and forward directions to produce fumarate and glutamate, respectively. Such a functional division of the cycle plausibly reflects the compromise between two contrasted forces: (1) the feedback inhibition by NADH and ATP on TCA enzymes in the light, and (2) the need to provide pH-buffering organic acids and carbon skeletons for nitrate absorption and assimilation. PMID:19675152

  13. Conductive Polymer Binder for High-Tap-Density Nanosilicon Material for Lithium-Ion Battery Negative Electrode Application

    DOE PAGES

    Zhao, Hui; Wei, Yang; Qiao, Ruimin; ...

    2015-11-24

    High-tap-density silicon nanomaterials are highly desirable as anodes for lithium ion batteries, due to their small surface area and minimum first-cycle loss. However, this material poses formidable challenges to polymeric binder design. Binders adhere on to the small surface area to sustain the drastic volume changes during cycling; also the low porosities and small pore size resulting from this material are detrimental to lithium ion transport. This study introduces a new binder, poly(1-pyrenemethyl methacrylate-co-methacrylic acid) (PPyMAA), for a high-tap-density nanosilicon electrode cycled in a stable manner with a first cycle efficiency of 82%-a value that is further improved to 87%more » when combined with graphite material. Incorporating the MAA acid functionalities does not change the lowest unoccupied molecular orbital (LUMO) features or lower the adhesion performance of the PPy homopolymer. Our single-molecule force microscopy measurement of PPyMAA reveals similar adhesion strength between polymer binder and anode surface when compared with conventional polymer such as homopolyacrylic acid (PAA), while being electronically conductive. Finally, the combined conductivity and adhesion afforded by the MAA and pyrene copolymer results in good cycling performance for the high-tap-density Si electrode.« less

  14. Bombyx mori cyclin-dependent kinase inhibitor is involved in regulation of the silkworm cell cycle.

    PubMed

    Tang, X-F; Zhou, X-L; Zhang, Q; Chen, P; Lu, C; Pan, M-H

    2018-06-01

    Cyclin-dependent kinase inhibitors (CKIs) are negative regulators of the cell cycle. They can bind to cyclin-dependent kinase (CDK)-cyclin complexes and inhibit CDK activities. We identified a single homologous gene of the CDK interacting protein/kinase inhibitory protein (Cip/Kip) family, BmCKI, in the silkworm, Bombyx mori. The gene transcribes two splice variants: a 654-bp-long BmCKI-L (the longer splice variant) encoding a protein with 217 amino acids and a 579-bp-long BmCKI-S (the shorter splice variant) encoding a protein with 192 amino acids. BmCKI-L and BmCKI-S contain the Cip/Kip family conserved cyclin-binding domain and the CDK-binding domain. They are localized in the nucleus and have an unconventional bipartite nuclear localization signal at amino acid residues 181-210. Overexpression of BmCKI-L or BmCKI-S affected cell cycle progression; the cell cycle was arrested in the first gap phase of cell cycle (G1). RNA interference of BmCKI-L or BmCKI-S led to cells accumulating in the second gap phase and the mitotic phase of cell cycle (G2/M). Both BmCKI-L and BmCKI-S are involved in cell cycle regulation and probably have similar effects. The transgenic silkworm with BmCKI-L overexpression (BmCKI-L-OE), exhibited embryonic lethal, larva developmental retardation and lethal phenotypes. These results suggest that BmCKI-L might regulate the growth and development of silkworm. These findings clarify the function of CKIs and increase our understanding of cell cycle regulation in the silkworm. © 2018 The Royal Entomological Society.

  15. Dihydrolipoyl dehydrogenase as a potential UVB target in skin epidermis; using an integrated approach of label-free quantitative proteomics and targeted metabolite analysis.

    PubMed

    Moon, Eunjung; Park, Hye Min; Lee, Choong Hwan; Do, Seon-Gil; Park, Jong-Moon; Han, Na-Young; Do, Moon Ho; Lee, Jong Ha; Lee, Hookeun; Kim, Sun Yeou

    2015-03-18

    Photodamage is extrinsically induced by overexposure to ultraviolet (UV) radiation, and it increases the risk of various skin disorders. Therefore, discovery of novel biomarkers of photodamage is important. In this study, using LC-MS/MS analysis of epidermis from UVB-irradiated hairless mice, we identified 57 proteins whose levels changed after UVB exposure, and selected 7 proteins related to the tricarboxylic acid (TCA) cycle through pathway analysis. Dihydrolipoyl dehydrogenase (DLD) was the only TCA cycle-associated protein that showed a decreased expression after the UVB exposure. We also performed targeted analysis to detect intermediates and products of the TCA cycle using GC-TOF-MS. Interestingly, malic acid and fumaric acid levels significantly decreased in the UVB-treated group. Our results demonstrate that DLD and its associated metabolites, malic acid and fumaric acid, may be candidate biomarkers of UVB-induced skin photoaging. Additionally, we showed that Aloe vera, a natural skin moisturizer, regulated DLD, malic acid and fumaric acid levels in UVB-exposed epidermis. Our strategy to integrate the proteome and targeted metabolite to detect novel UVB targets will lead to a better understanding of skin photoaging and photodamage. Our study also supports that A. vera exerts significant anti-photodamage activity via regulation of DLD, a novel UVB target, in the epidermis. This study is the first example of an integration of proteomic and metabolite analysis techniques to find new biomarker candidates for the regulation of the UVB-induced skin photoaging. DLD, malic acid, and fumaric acid can be used for development of cosmeceuticals and nutraceuticals regulating the change of skin metabolism induced by the UVB overexposure. Moreover, this is also the first attempt to investigate the role of the TCA cycle in photodamaged epidermis. Our integration of the proteomic and targeted metabolite analyses will lead to a better understanding of the unidentified photobiological results from UVB-irradiated models and can elicit new diagnostic and treatment strategies based on altered metabolism. Copyright © 2015. Published by Elsevier B.V.

  16. Accumulation of 5-Oxoproline in Mouse Tissues After Inhibition of 5-Oxoprolinase and Administration of Amino Acids: Evidence for Function of the γ-Glutamyl Cycle*

    PubMed Central

    Van Der Werf, Paul; Stephani, Ralph A.; Meister, Alton

    1974-01-01

    5-Oxoprolinase catalyzes the conversion of 5-oxo-L-proline (L-pyroglutamate, L-2-pyrrolidone-5-carboxylate) to L-glutamate with concomitant stoichiometric cleavage of ATP to ADP and inorganic orthophosphate. In this reaction, a step in the γ-glutamyl cycle, 5-oxoproline (formed by the action of γ-glutamylcyclotransferase on γ-glutamyl amino acids, which are in turn formed by transpeptidation of amino acids with glutathione), is made available for glutathione synthesis. When mice are injected with L-2-imidazolidone-4-carboxylate, a competitive inhibitor of 5-oxoprolinase, they accumulate 5-oxoproline in their tissues (kidney, liver, brain, and eye) and excrete it in the urine. Mice given the inhibitor together with one of several L-amino acids accumulate and excrete much more 5-oxoproline than when they are given the inhibitor alone. Such augmentation of 5-oxoproline accumulation offers evidence for the function of the γ-glutamyl cycle in vivo and supports the view that 5-oxoproline is a quantitatively significant metabolite. Images PMID:4151516

  17. The synthesis of glutamic acid in the absence of enzymes: Implications for biogenesis

    NASA Technical Reports Server (NTRS)

    Morowitz, Harold; Peterson, Eta; Chang, Sherwood

    1995-01-01

    This paper reports on the non-enzymatic aqueous phase synthesis of amino acids from keto acids, ammonia and reducing agents. The facile synthesis of key metabolic intermediates, particularly in the glycolytic pathway, the citric acid cycle, and the first step of amino acid synthesis, lead to new ways of looking at the problem of biogenesis.

  18. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  19. Glutamatergic and GABAergic neurotransmitter cycling and energy metabolism in rat cerebral cortex during postnatal development.

    PubMed

    Chowdhury, Golam M I; Patel, Anant B; Mason, Graeme F; Rothman, Douglas L; Behar, Kevin L

    2007-12-01

    The contribution of glutamatergic and gamma-aminobutyric acid (GABA)ergic neurons to oxidative energy metabolism and neurotransmission in the developing brain is not known. Glutamatergic and GABAergic fluxes were assessed in neocortex of postnatal day 10 (P10) and 30 (P30) urethane-anesthetized rats infused intravenously with [1,6-(13)C(2)]glucose for different time intervals (time course) or with [2-(13)C]acetate for 2 to 3 h (steady state). Amino acid levels and (13)C enrichments were determined in tissue extracts ex vivo using (1)H-[(13)C]-NMR spectroscopy. Metabolic fluxes were estimated from the best fits of a three-compartment metabolic model (glutamatergic neurons, GABAergic neurons, and astroglia) to the (13)C-enrichment time courses of amino acids from [1,6-(13)C(2)]glucose, constrained by the ratios of neurotransmitter cycling (V(cyc))-to-tricarboxylic acid (TCA) cycle flux (V(TCAn)) calculated from the steady-state [2-(13)C]acetate enrichment data. From P10 to P30 increases in total neuronal (glutamate plus GABA) TCA cycle flux (3 x ; 0.24+/-0.05 versus 0.71+/-0.07 micromol per g per min, P<0.0001) and total neurotransmitter cycling flux (3.1 to 5 x ; 0.07 to 0.11 (+/-0.03) versus 0.34+/-0.03 micromol per g per min, P<0.0001) were approximately proportional. Incremental changes in total cycling (DeltaV(cyc(tot))) and neuronal TCA cycle flux (DeltaV(TCAn(tot))) between P10 and P30 were 0.23 to 0.27 and 0.47 micromol per g per min, respectively, similar to the approximately 1:2 relationship previously reported for adult cortex. For the individual neurons, increases in V(TCAn) and V(cyc) were similar in magnitude (glutamatergic neurons, 2.7 x versus 2.8 to 4.6 x ; GABAergic neurons, approximately 5 x versus approximately 7 x), although GABAergic flux changes were larger. The findings show that glutamate and GABA neurons undergo large and approximately proportional increases in neurotransmitter cycling and oxidative energy metabolism during this major postnatal growth spurt.

  20. Chemical heat pump and chemical energy storage system

    DOEpatents

    Clark, Edward C.; Huxtable, Douglas D.

    1985-08-06

    A chemical heat pump and storage system employs sulfuric acid and water. In one form, the system includes a generator and condenser, an evaporator and absorber, aqueous acid solution storage and water storage. During a charging cycle, heat is provided to the generator from a heat source to concentrate the acid solution while heat is removed from the condenser to condense the water vapor produced in the generator. Water is then stored in the storage tank. Heat is thus stored in the form of chemical energy in the concentrated acid. The heat removed from the water vapor can be supplied to a heat load of proper temperature or can be rejected. During a discharge cycle, water in the evaporator is supplied with heat to generate water vapor, which is transmitted to the absorber where it is condensed and absorbed into the concentrated acid. Both heats of dilution and condensation of water are removed from the thus diluted acid. During the discharge cycle the system functions as a heat pump in which heat is added to the system at a low temperature and removed from the system at a high temperature. The diluted acid is stored in an acid storage tank or is routed directly to the generator for reconcentration. The generator, condenser, evaporator, and absorber all are operated under pressure conditions specified by the desired temperature levels for a given application. The storage tanks, however, can be maintained at or near ambient pressure conditions. In another form, the heat pump system is employed to provide usable heat from waste process heat by upgrading the temperature of the waste heat.

  1. Flower abscission in Vitis vinifera L. triggered by gibberellic acid and shade discloses differences in the underlying metabolic pathways

    PubMed Central

    Domingos, Sara; Scafidi, Pietro; Cardoso, Vania; Leitao, Antonio E.; Di Lorenzo, Rosario; Oliveira, Cristina M.; Goulao, Luis F.

    2015-01-01

    Understanding abscission is both a biological and an agronomic challenge. Flower abscission induced independently by shade and gibberellic acid (GAc) sprays was monitored in grapevine (Vitis vinifera L.) growing under a soilless greenhouse system during two seasonal growing conditions, in an early and late production cycle. Physiological and metabolic changes triggered by each of the two distinct stimuli were determined. Environmental conditions exerted a significant effect on fruit set as showed by the higher natural drop rate recorded in the late production cycle with respect to the early cycle. Shade and GAc treatments increased the percentage of flower drop compared to the control, and at a similar degree, during the late production cycle. The reduction of leaf gas exchanges under shade conditions was not observed in GAc treated vines. The metabolic profile assessed in samples collected during the late cycle differently affected primary and secondary metabolisms and showed that most of the treatment-resulting variations occurred in opposite trends in inflorescences unbalanced in either hormonal or energy deficit abscission-inducing signals. Particularly concerning carbohydrates metabolism, sucrose, glucose, tricarboxylic acid metabolites and intermediates of the raffinose family oligosaccharides pathway were lower in shaded and higher in GAc samples. Altered oxidative stress remediation mechanisms and indolacetic acid (IAA) concentration were identified as abscission signatures common to both stimuli. According to the global analysis performed, we report that grape flower abscission mechanisms triggered by GAc application and C-starvation are not based on the same metabolic pathways. PMID:26157448

  2. Effect of changes in fat availability on exercise capacity in McArdle disease.

    PubMed

    Andersen, Susanne T; Jeppesen, Tina D; Taivassalo, Tanja; Sveen, Marie-Louise; Heinicke, Katja; Haller, Ronald G; Vissing, John

    2009-06-01

    The major fuel for exercising muscle at low exercise intensities is fat. To investigate the role of fat metabolism in McArdle disease (also known as glycogen storage disease type V), an inborn error of muscle glycogenolysis, by manipulating free fatty acid availability for oxidation during exercise. Randomized, placebo-controlled, crossover trial. Hospitalized care. Ten patients (8 men and 2 women) with McArdle disease. Patients cycled at a constant workload corresponding to 70% of their maximum oxygen consumption. In random order and on separate days, patients received nicotinic acid (a known blocker of lipolysis) to decrease the availability of free fatty acids or 20% Intralipid infusion to increase free fatty acid availability during exercise. Results were compared with placebo (isotonic sodium chloride solution infusion) and glucose infusion trials. Exercise tolerance was assessed by heart rate response to exercise during different infusions. Free fatty acid levels more than tripled by Intralipid infusion and were halved by nicotinic acid administration. Heart rate was significantly higher during exercise in the Intralipid infusion and nicotinic acid trials compared with the placebo and glucose infusion trials, an effect that was observed before and after the patients had experienced the second wind phenomenon. Lipids are an important source of fuel for exercising muscle in McArdle disease, but maximal rates of fat oxidation seem limited and cannot be increased above physiologically normal rates during exercise. This limitation is probably caused by a metabolic bottleneck in the tricarboxylic acid cycle due to impaired glycolytic flux in McArdle disease. Therapies aimed at enhancing fat use in McArdle disease should be combined with interventions targeting expansion of the tricarboxylic acid cycle.

  3. Detection and formation scenario of citric acid, pyruvic acid, and other possible metabolism precursors in carbonaceous meteorites

    PubMed Central

    Cooper, George; Reed, Chris; Nguyen, Dang; Carter, Malika; Wang, Yi

    2011-01-01

    Carbonaceous meteorites deliver a variety of organic compounds to Earth that may have played a role in the origin and/or evolution of biochemical pathways. Some apparently ancient and critical metabolic processes require several compounds, some of which are relatively labile such as keto acids. Therefore, a prebiotic setting for any such individual process would have required either a continuous distant source for the entire suite of intact precursor molecules and/or an energetic and compact local synthesis, particularly of the more fragile members. To date, compounds such as pyruvic acid, oxaloacetic acid, citric acid, isocitric acid, and α-ketoglutaric acid (all members of the citric acid cycle) have not been identified in extraterrestrial sources or, as a group, as part of a “one pot” suite of compounds synthesized under plausibly prebiotic conditions. We have identified these compounds and others in carbonaceous meteorites and/or as low temperature (laboratory) reaction products of pyruvic acid. In meteorites, we observe many as part of three newly reported classes of compounds: keto acids (pyruvic acid and homologs), hydroxy tricarboxylic acids (citric acid and homologs), and tricarboxylic acids. Laboratory syntheses using 13C-labeled reactants demonstrate that one compound alone, pyruvic acid, can produce several (nonenzymatic) members of the citric acid cycle including oxaloacetic acid. The isotopic composition of some of the meteoritic keto acids points to interstellar or presolar origins, indicating that such compounds might also exist in other planetary systems. PMID:21825143

  4. Detection and formation scenario of citric acid, pyruvic acid, and other possible metabolism precursors in carbonaceous meteorites.

    PubMed

    Cooper, George; Reed, Chris; Nguyen, Dang; Carter, Malika; Wang, Yi

    2011-08-23

    Carbonaceous meteorites deliver a variety of organic compounds to Earth that may have played a role in the origin and/or evolution of biochemical pathways. Some apparently ancient and critical metabolic processes require several compounds, some of which are relatively labile such as keto acids. Therefore, a prebiotic setting for any such individual process would have required either a continuous distant source for the entire suite of intact precursor molecules and/or an energetic and compact local synthesis, particularly of the more fragile members. To date, compounds such as pyruvic acid, oxaloacetic acid, citric acid, isocitric acid, and α-ketoglutaric acid (all members of the citric acid cycle) have not been identified in extraterrestrial sources or, as a group, as part of a "one pot" suite of compounds synthesized under plausibly prebiotic conditions. We have identified these compounds and others in carbonaceous meteorites and/or as low temperature (laboratory) reaction products of pyruvic acid. In meteorites, we observe many as part of three newly reported classes of compounds: keto acids (pyruvic acid and homologs), hydroxy tricarboxylic acids (citric acid and homologs), and tricarboxylic acids. Laboratory syntheses using (13)C-labeled reactants demonstrate that one compound alone, pyruvic acid, can produce several (nonenzymatic) members of the citric acid cycle including oxaloacetic acid. The isotopic composition of some of the meteoritic keto acids points to interstellar or presolar origins, indicating that such compounds might also exist in other planetary systems.

  5. Atomic Layer Deposition of L-Alanine Polypeptide

    DOE PAGES

    Fu, Yaqin; Li, Binsong; Jiang, Ying-Bing; ...

    2014-10-30

    L-Alanine polypeptide thin films were synthesized via atomic layer deposition (ALD). Rather, instead of using an amino acid monomer as the precursor, an L-alanine amino acid derivatized with a protecting group was used to prevent self-polymerization, increase the vapor pressure, and allow linear cycle-by-cycle growth emblematic of ALD. Moreover, the successful deposition of a conformal polypeptide film has been confirmed by FTIR, TEM, and Mass Spectrometry, and the ALD process has been extended to polyvaline.

  6. Diffusion of tricarboxylic acid cycle enzymes in the mitochondrial matrix in vivo. Evidence for restricted mobility of a multienzyme complex.

    PubMed

    Haggie, Peter M; Verkman, A S

    2002-10-25

    It has been proposed that enzymes in many metabolic pathways, including the tricarboxylic acid cycle in the mitochondrial matrix, are physically associated to facilitate substrate channeling and overcome diffusive barriers. We have used fluorescence recovery after photobleaching to measure the diffusional mobilities of chimeras consisting of green fluorescent protein (GFP) fused to the C terminus of four tricarboxylic acid cycle enzymes: malate dehydrogenase, citrate synthase, isocitrate dehydrogenase, and succinyl-CoA synthetase. The GFP-enzyme chimeras were localized selectively in the mitochondrial matrix in transfected Chinese hamster ovary (CHO) and COS7 cells. Laser photobleaching using a 0.7-microm diameter spot demonstrated restricted diffusion of the GFP-enzyme chimeras. Interestingly, all four chimeras had similar diffusional characteristics, approximately 45% of each chimera was mobile and had a diffusion coefficient of 4 x 10(-8) cm(2)/s. In contrast, unconjugated GFP in the mitochondrial matrix (targeted using COX8 leader sequence) diffused freely (nearly 100% mobility) with a greater diffusion coefficient of 20 x 10(-8) cm(2)/s. The mobility of the GFP-enzyme chimeras was insensitive to substrate source, ATP depletion, or inhibition of the adenine nucleotide translocase. These results indicate similar mobility characteristics of unrelated tricarboxylic acid cycle enzymes having different sizes and physical properties, providing biophysical evidence for a diffusible multienzyme complex in the mitochondrial matrix.

  7. Climatic cycles inferred from the aminostratigraphy and aminochronology of Quaternary dunes and palaeosols from the eastern islands of the Canary Archipelago

    NASA Astrophysics Data System (ADS)

    Ortiz, J. E.; Torres, T.; Yanes, Y.; Castillo, C.; de La Nuez, J.; Ibáñez, M.; Alonso, M. R.

    2006-03-01

    Aminochronological and aminostratigraphical methods have been used to study the Quaternary aeolian deposits from the islands located east of the Canary Archipelago (Fuerteventura and Lanzarote islands and La Graciosa, Montaña Clara and Alegranza islets). The extent of racemisation/epimerisation of four amino acids (isoleucine, aspartic acid, phenylalanine and glutamic acid) was measured in land snail shells of the genus Theba. The age calculation algorithms of these amino acids have been determined to permit the numerical dating of these deposits. Eight Aminozones, each defining dune/palaeosol-formation episodes, have been distinguished and dated at 48.6 +/- 6.4, 42.5 +/- 6.0, 37.8 +/- 4.6, 29.4 +/- 4.8, 22.4 +/- 4.5, 14.9 +/- 3.6, 11.0 +/- 4.0 and 5.4 +/- 1.1 ka BP, the first five of them defining cycles of 5-7ka.The alternation of palaeosols and aeolian deposits, which are related to abrupt transitions from humid to arid conditions, are the reflection of globally induced changes in North Africa palaeoenvironmental conditions linked to the effect of African palaeomonsoons on the trade winds and the Saharan Air Layer. Probably these aeolian cycles, with a recurrence period of 5-7ka, are the expression of multiples of the 2.4ka solar-cycle.

  8. Cdc6 localizes to S- and G2-phase centrosomes in a cell cycle-dependent manner

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

    Kim, Gwang Su; Kang, Jeeheon; Bang, Sung Woong

    2015-01-16

    Highlights: • Cdc6 protein is a component of the pre-replicative complex required for chromosomal replication initiation. • Cdc6 localized to centrosomes of S and G2 phases in a cell cycle-dependent manner. • The centrosomal localization was governed by centrosomal localization signal sequences of Cdc6. • Deletions or substitution mutations on the centrosomal localization signal interfered with centrosomal localization of the Cdc6 proteins. - Abstract: The Cdc6 protein has been primarily investigated as a component of the pre-replicative complex for the initiation of chromosome replication, which contributes to maintenance of chromosomal integrity. Here, we show that Cdc6 localized to the centrosomesmore » during S and G2 phases of the cell cycle. The centrosomal localization was mediated by Cdc6 amino acid residues 311–366, which are conserved within other Cdc6 homologues and contains a putative nuclear export signal. Deletions or substitutions of the amino acid residues did not allow the proteins to localize to centrosomes. In contrast, DsRed tag fused to the amino acid residues localized to centrosomes. These results indicated that a centrosome localization signal is contained within amino acid residues 311–366. The cell cycle-dependent centrosomal localization of Cdc6 in S and G2 phases suggest a novel function of Cdc6 in centrosomes.« less

  9. Asymmetric Fluorination of α-Branched Cyclohexanones Enabled by a Combination of Chiral Anion Phase-Transfer Catalysis and Enamine Catalysis using Protected Amino Acids

    PubMed Central

    2015-01-01

    We report a study involving the successful merger of two separate chiral catalytic cycles: a chiral anion phase-transfer catalysis cycle to activate Selectfluor and an enamine activation cycle, using a protected amino acid as organocatalyst. We have demonstrated the viability of this approach with the direct asymmetric fluorination of α-substituted cyclohexanones to generate quaternary fluorine-containing stereocenters. With these two chiral catalytic cycles operating together in a matched sense, high enantioselectivites can be achieved, and we envisage that this dual catalysis method has the potential to be more broadly applicable, given the breadth of enamine catalysis. It also represents a rare example of chiral enamine catalysis operating successfully on α-branched ketones, substrates commonly inert to this activation mode. PMID:24684209

  10. Viability of pyrite pulled metabolism in the ‘iron-sulfur world’ theory: Quantum chemical assessment

    NASA Astrophysics Data System (ADS)

    Michalkova, Andrea; Kholod, Yana; Kosenkov, Dmytro; Gorb, Leonid; Leszczynski, Jerzy

    2011-04-01

    The viability of pyrite-pulled metabolism in the 'iron-sulfur world' theory was assessed using a simple model of iron-nickel sulfide (Fe-Ni-S) surface and data obtained from quantum chemical calculations. We have investigated how the individual reactions in the carbon fixation cycle (carboxylic acids formation) on an Fe-Ni-S surface could have operated to produce carboxylic acids from carbon oxide and water. The proposed model cycle reveals how the individual reactions might have functioned and provides the thermodynamics of each step of the proposed pathway. The feasibility of individual reactions, as well the whole cycle was considered. The reaction of acetic acid production from CH 3SH and CO on an Fe-Ni sulfide surface was revealed to be endergonic with a few partial steps having positive Gibbs free energy. On the other hand, the pyrite formation was found to be slightly exergonic. The significance of the catalytic activity of transition metal sulfides in generation of acetic acid was shown. The Gibbs free energy values indicate that the acetic acid synthesis is unfavorable to proceed on the studied Fe-Ni-S model under simulated conditions. The importance of these results in terms of a primordial chemistry on iron-nickel sulfide surfaces is discussed.

  11. Investigation of the Evolution of Crystal Size and Shape during Temperature Cycling and in the Presence of a Polymeric Additive Using Combined Process Analytical Technologies

    PubMed Central

    2017-01-01

    Crystal size and shape can be manipulated to enhance the qualities of the final product. In this work the steady-state shape and size of succinic acid crystals, with and without a polymeric additive (Pluronic P123) at 350 mL, scale is reported. The effect of the amplitude of cycles as well as the heating/cooling rates is described, and convergent cycling (direct nucleation control) is compared to static cycling. The results show that the shape of succinic acid crystals changes from plate- to diamond-like after multiple cycling steps, and that the time required for this morphology change to occur is strongly related to the type of cycling. Addition of the polymer is shown to affect both the final shape of the crystals and the time needed to reach size and shape steady-state conditions. It is shown how this phenomenon can be used to improve the design of the crystallization step in order to achieve more efficient downstream operations and, in general, to help optimize the whole manufacturing process. PMID:28867966

  12. Activities of Tricarboxylic Acid Cycle Enzymes, Glyoxylate Cycle Enzymes, and Fructose Diphosphatase in Bakers' Yeast During Adaptation to Acetate Oxidation

    PubMed Central

    Gosling, J. P.; Duggan, P. F.

    1971-01-01

    Bakers' yeast oxidizes acetate at a high rate only after an adaptation period during which the capacity of the glyoxylate cycle is found to increase. There was apparently no necessity for the activity of acetyl-coenzyme A synthetase, the capacity of the tricarboxylic acid cycle, or the concentrations of the cytochromes to increase for this adaptation to occur. Elevation of fructose 1,6 diphosphatase occurred only when acetate oxidation was nearly maximal. Cycloheximide almost completely inhibited adaptation as well as increases in the activities of isocitrate lyase and aconitate hydratase, the only enzymes assayed. p-Fluorophenylalanine was partially effective and chloramphenicol did not inhibit at all. The presence of ammonium, which considerably delayed adaptation of the yeast to acetate oxidation, inhibited the increases in the activities of the glyoxylate cycle enzymes to different degrees, demonstrating noncoordinate control of these enzymes. Under the various conditions, the only enzyme activity increase consistently related to the rising oxygen uptake rate was that of isocitrate lyase which apparently limited the activity of the cycle. PMID:5557595

  13. Cell cycle arrest and induction of apoptosis by cajanin stilbene acid from Cajanus cajan in breast cancer cells.

    PubMed

    Fu, Yujie; Kadioglu, Onat; Wiench, Benjamin; Wei, Zuofu; Gao, Chang; Luo, Meng; Gu, Chengbo; Zu, Yuangang; Efferth, Thomas

    2015-04-15

    The low abundant cajanin stilbene acid (CSA) from Pigeon Pea (Cajanus cajan) has been shown to kill estrogen receptor α positive cancer cells in vitro and in vivo. Downstream effects such as cell cycle and apoptosis-related mechanisms have not been analyzed yet. We analyzed the activity of CSA by means of flow cytometry (cell cycle distribution, mitochondrial membrane potential, MMP), confocal laser scanning microscopy (MMP), DNA fragmentation assay (apoptosis), Western blotting (Bax and Bcl-2 expression, caspase-3 activation) as well as mRNA microarray hybridization and Ingenuity pathway analysis. CSA induced G2/M arrest and apoptosis in a concentration-dependent manner from 8.88 to 14.79 µM. The MMP broke down, Bax was upregulated, Bcl-2 downregulated and caspase-3 activated. Microarray profiling revealed that CSA affected BRCA-related DNA damage response and cell cycle-regulated chromosomal replication pathways. CSA inhibited breast cancer cells by DNA damage and cell cycle-related signaling pathways leading to cell cycle arrest and apoptosis. Copyright © 2015 Elsevier GmbH. All rights reserved.

  14. Novel insights into the bioenergetics of mixed-acid fermentation: can hydrogen and proton cycles combine to help maintain a proton motive force?

    PubMed

    Trchounian, Armen; Gary Sawers, R

    2014-01-01

    Escherichia coli possesses four [NiFe]-hydrogenases that catalyze the reversible redox reaction of 2H(+) + 2e(-) ↔ H2. These enzymes together have the potential to form a hydrogen cycle across the membrane. Their activity, operational direction, and interaction with each other depend on the fermentation substrate and particularly pH. The enzymes producing H2 are likely able to translocate protons through the membrane. Moreover, the activity of some of these enzymes is dependent on the F0 F1 -ATPase, thus linking a proton cycle with the cycling of hydrogen. These two cycles are suggested to have a primary basic role in modulating the cell's energetics during mixed-acid fermentation, particularly in response to pH. Nevertheless, the mechanisms underlying the physical interactions between these enzyme complexes, as well as how this is controlled, are still not clearly understood. Here, we present a synopsis of the potential impact of proton-hydrogen cycling in fermentative bioenergetics. © 2013 International Union of Biochemistry and Molecular Biology.

  15. Guidance and Control Software Project Data - Volume 4: Configuration Management and Quality Assurance Documents

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J. (Editor)

    2008-01-01

    The Guidance and Control Software (GCS) project was the last in a series of software reliability studies conducted at Langley Research Center between 1977 and 1994. The technical results of the GCS project were recorded after the experiment was completed. Some of the support documentation produced as part of the experiment, however, is serving an unexpected role far beyond its original project context. Some of the software used as part of the GCS project was developed to conform to the RTCA/DO-178B software standard, "Software Considerations in Airborne Systems and Equipment Certification," used in the civil aviation industry. That standard requires extensive documentation throughout the software development life cycle, including plans, software requirements, design and source code, verification cases and results, and configuration management and quality control data. The project documentation that includes this information is open for public scrutiny without the legal or safety implications associated with comparable data from an avionics manufacturer. This public availability has afforded an opportunity to use the GCS project documents for DO-178B training. This report provides a brief overview of the GCS project, describes the 4-volume set of documents and the role they are playing in training, and includes configuration management and quality assurance documents from the GCS project. Volume 4 contains six appendices: A. Software Accomplishment Summary for the Guidance and Control Software Project; B. Software Configuration Index for the Guidance and Control Software Project; C. Configuration Management Records for the Guidance and Control Software Project; D. Software Quality Assurance Records for the Guidance and Control Software Project; E. Problem Report for the Pluto Implementation of the Guidance and Control Software Project; and F. Support Documentation Change Reports for the Guidance and Control Software Project.

  16. Teaching about citric acid cycle using plant mitochondrial preparations: Some assays for use in laboratory courses*.

    PubMed

    Vicente, Joaquim A F; Gomes-Santos, Carina S S; Sousa, Ana Paula M; Madeira, Vítor M C

    2005-03-01

    Potato tubers and turnip roots were used to prepare purified mitochondria for laboratory practical work in the teaching of the citric acid cycle (TCA cycle). Plant mitochondria are particularly advantageous over the animal fractions to demonstrate the TCA cycle enzymatic steps, by using simple techniques to measure O(2) consumption and transmembrane potential (ΔΨ). The several TCA cycle intermediates induce specific enzyme activities, which can be identified by respiratory parameters. Such a strategy is also used to evidence properties of the TCA cycle enzymes: ADP stimulation of isocitrate dehydrogenase and α-ketoglutarate dehydrogenase; activation by citrate of downstream oxidation steps, e.g. succinate dehydrogenase; and regulation of the activity of isocitrate dehydrogenase by citrate action on the citrate/isocitrate carrier. Furthermore, it has been demonstrated that, in the absence of exogenous Mg(2+) , isocitrate-dependent respiration favors the alternative oxidase pathway, as judged by changes of the ADP/O elicited by the inhibitor n-propyl galate. These are some examples of assays related with TCA cycle intermediates we can use in laboratory courses. Copyright © 2005 International Union of Biochemistry and Molecular Biology, Inc.

  17. Influence of silicon doping of titanium nickelide near-surface layers on alloy cytocompatibility

    NASA Astrophysics Data System (ADS)

    Lotkov, A. I.; Matveev, A. L.; Artemyeva, L. V.; Meysner, S. N.; Matveeva, V. A.; Kudryashov, A. N.

    2017-12-01

    The cytocompatibility of titanium nickelide (TiNi) with near-surface layers doped with silicon ions was studied on mesenchymal stem cells of rat bone marrow cultivated in vitro. The cytotoxic effect of eluted components of material on the mesenchymal stem cells was determined using a RTCA iCELLigence cellular analyzer. The proliferative activity of mesenchymal stem cells cultivated in the presence or on the surfaces of titanium nickelide samples was estimated from the cell mitochondrial respiration rate in MTT tests using [2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium] tetrazolium salt. It is shown that ion plasma modification of near-surface layers of titanium nickelide with silicon improves the cytocompatibility of the alloy.

  18. Software verification plan for GCS. [guidance and control software

    NASA Technical Reports Server (NTRS)

    Dent, Leslie A.; Shagnea, Anita M.; Hayhurst, Kelly J.

    1990-01-01

    This verification plan is written as part of an experiment designed to study the fundamental characteristics of the software failure process. The experiment will be conducted using several implementations of software that were produced according to industry-standard guidelines, namely the Radio Technical Commission for Aeronautics RTCA/DO-178A guidelines, Software Consideration in Airborne Systems and Equipment Certification, for the development of flight software. This plan fulfills the DO-178A requirements for providing instructions on the testing of each implementation of software. The plan details the verification activities to be performed at each phase in the development process, contains a step by step description of the testing procedures, and discusses all of the tools used throughout the verification process.

  19. Airborne polar experiment (APE): tests and qualification of the scientific instrumentation installed on the stratospheric platform M-55 aircraft

    NASA Astrophysics Data System (ADS)

    de Rossi, Giuseppe; Puccini, Massimo; Puccetti, Giuseppe

    1995-12-01

    The paper describes the environmental tests to be carried out on the scientific instrumentation to be flown on the M-55 Geophysika in the frame of the APE Program. The instruments, developed by different European research institutes, are for remote sensing and in situ measurements of the major components of the Earth's stratosphere. The paper presents the technological activities that ENEA (Ente Nazionale per le Nuove Tecnologie l'Energia e l'Ambiente) is carrying out in its laboratories to verify the correspondence of the various instruments to meet the requirements for airborne application. The reference documents used have been the RTCA/DO-160C and the MDB (Myasishchev Design Bureau) specifications.

  20. The Path of Carbon in Photosynthesis XX. The Steady State

    DOE R&D Accomplishments Database

    Calvin, M.; Massini, Peter

    1952-09-01

    The separation of the phenomenon of photosynthesis in green plants into a photochemical reaction and into the light-dependent reduction of carbon dioxide is discussed, The reduction of carbon dioxide and the fate of the assimilated carbon were investigated with the help of the tracer technique (exposure of the planks to the radioactive C{sup 14}O{sub 2}) and of paper chromatography. A reaction cycle is proposed in which phosphoglyceric acid is the first isolable assimilations product. Analyses of the algal extracts which had assimilated radioactive carbon dioxide in a stationary condition ('steady-state' photosynthesis) for a long time provided further information concerning the proposed cycle and permitted the approximate estimation, for a number of compounds of what fraction of each compound was taking part in the cycle. The earlier supposition that light influences the respiration cycle was confirmed. The possibility of the assistance of {alpha}-lipoic acid, or of a related substance, in this influence and in the photosynthesis cycle, is discussed.

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