Collective effects of torsion in FtsZ filaments

NASA Astrophysics Data System (ADS)

González de Prado Salas, Pablo; Tarazona, Pedro

2016-04-01

Recent evidence points to the presence of torsion in FtsZ bonds. In addition, experiments with FtsZ mutants on surfaces resulted in new aggregates that cannot be explained by older models for FtsZ dynamics. We use an interaction model for FtsZ derived from molecular dynamics simulations and expand a fine-grained lattice model used to describe FtsZ aggregates on a surface. This new model includes different anchoring angles for the monomers and allows bond twist, two ingredients that oppose each other resulting in a more dynamic and interesting system. We study the role and importance of these conflicting elements and how the aggregates are characterized by the different interaction parameters.

FTS evolution

NASA Technical Reports Server (NTRS)

Provost, David E.

1990-01-01

Viewgraphs on flight telerobotic servicer evolution are presented. Topics covered include: paths for FTS evolution; frequently performed actions; primary task states; EPS radiator panel installation; generic task definitions; path planning; non-contact alignment; contact planning and control; and human operator interface.

Regulation of the expression of the cell-cycle gene ftsZ by DicF antisense RNA. Division does not require a fixed number of FtsZ molecules.

PubMed

Tétart, F; Bouché, J P

1992-03-01

We show that the 53-nucleotide RNA molecule encoded by gene dicF blocks cell division in Escherichia coli by inhibiting the translation of ftsZ mRNA. Such a role for dicF had been predicted on the basis of the complementarity of DicF RNA with the ribosome-binding region of the ftsZ mRNA. An analysis of ftsZ expression at its chromosomal locus, and of an ftsZ-lacZ translational fusion controlled by promoters ftsZ1p and ftsZ2p only, indicates that ftsZ is not autoregulated. Partial inhibition of FtsZ synthesis leads to increased cell size. However, the number of FtsZ molecules per cell can be reduced threefold without affecting the division rate significantly. Our results suggest that septation is not triggered by a fixed number of newly synthesized FtsZ molecules per cell.

Ruthenium red-induced bundling of bacterial cell division protein, FtsZ.

PubMed

Santra, Manas Kumar; Beuria, Tushar K; Banerjee, Abhijit; Panda, Dulal

2004-06-18

The assembly of FtsZ plays a major role in bacterial cell division, and it is thought that the assembly dynamics of FtsZ is a finely regulated process. Here, we show that ruthenium red is able to modulate FtsZ assembly in vitro. In contrast to the inhibitory effects of ruthenium red on microtubule polymerization, we found that a substoichiometric concentration of ruthenium red strongly increased the light-scattering signal of FtsZ assembly. Further, sedimentable polymer mass was increased by 1.5- and 2-fold in the presence of 2 and 10 microm ruthenium red, respectively. In addition, ruthenium red strongly reduced the GTPase activity and prevented dilution-induced disassembly of FtsZ polymers. Electron microscopic analysis showed that 4-10 microm of ruthenium red produced thick bundles of FtsZ polymers. The significant increase in the light-scattering signal and pelletable polymer mass in the presence of ruthenium red seemed to be due to the bundling of FtsZ protofilaments into larger polymers rather than the actual increase in the level of polymeric FtsZ. Furthermore, ruthenium red was found to copolymerize with FtsZ, and the copolymerization of substoichiometric amounts of ruthenium red with FtsZ polymers promoted cooperative assembly of FtsZ that produced large bundles. Calcium inhibited the binding of ruthenium red to FtsZ. However, a concentration of calcium 1000-fold higher than that of ruthenium red was required to produce similar effects on FtsZ assembly. Ruthenium red strongly modulated FtsZ polymerization, suggesting the presence of an important regulatory site on FtsZ and suggesting that a natural ligand, which mimics the action of ruthenium red, may regulate the assembly of FtsZ in bacteria.

Probing for Binding Regions of the FtsZ Protein Surface through Site-Directed Insertions: Discovery of Fully Functional FtsZ-Fluorescent Proteins

PubMed Central

Moore, Desmond A.; Whatley, Zakiya N.; Joshi, Chandra P.; Osawa, Masaki

2016-01-01

ABSTRACT FtsZ, a bacterial tubulin homologue, is a cytoskeletal protein that assembles into protofilaments that are one subunit thick. These protofilaments assemble further to form a “Z ring” at the center of prokaryotic cells. The Z ring generates a constriction force on the inner membrane and also serves as a scaffold to recruit cell wall remodeling proteins for complete cell division in vivo. One model of the Z ring proposes that protofilaments associate via lateral bonds to form ribbons; however, lateral bonds are still only hypothetical. To explore potential lateral bonding sites, we probed the surface of Escherichia coli FtsZ by inserting either small peptides or whole fluorescent proteins (FPs). Among the four lateral surfaces on FtsZ protofilaments, we obtained inserts on the front and back surfaces that were functional for cell division. We concluded that these faces are not sites of essential interactions. Inserts at two sites, G124 and R174, located on the left and right surfaces, completely blocked function, and these sites were identified as possible sites for essential lateral interactions. However, the insert at R174 did not interfere with association of protofilaments into sheets and bundles in vitro. Another goal was to find a location within FtsZ that supported insertion of FP reporter proteins while allowing the FtsZ-FPs to function as the sole source of FtsZ. We discovered one internal site, G55-Q56, where several different FPs could be inserted without impairing function. These FtsZ-FPs may provide advances for imaging Z-ring structure by superresolution techniques. IMPORTANCE One model for the Z-ring structure proposes that protofilaments are assembled into ribbons by lateral bonds between FtsZ subunits. Our study excluded the involvement of the front and back faces of the protofilament in essential interactions in vivo but pointed to two potential lateral bond sites, on the right and left sides. We also identified an FtsZ loop where

Algorithm development for the TIR bands of GOSAT-2/TANSO-FTS-2: lessons from GOSAT/TANSO-FTS TIR CO2 and CH4 measurement

NASA Astrophysics Data System (ADS)

Saitoh, N.; Yamada, A.; Itatsu, T.; Imasu, R.; Shiomi, K.; Niwa, Y.

2017-12-01

Greenhouse Gases Observing Satellite-2 (GOSAT-2), the successor of GOSAT, is planned to be launched in a year or so later. Thermal and Near Infrared Sensor for Carbon Observation (TANSO)-Fourier Transform Spectrometer-2 (FTS-2) on board the GOSAT-2 has two bands in the thermal infrared (TIR) region from 5.6 to 14.3 μm. We have developed an algorithm to retrieve CO2 and CH4 vertical profiles from the GOSAT/TANSO-FTS TIR band [Saitoh et al., 2009; 2016] and performed validation analysis for the TANSO-FTS TIR CO2 and CH4 products. Saitoh et al. [2016, 2017] showed that TANSO-FTS TIR V1 CO2 data had a seasonal- and regional-dependent negative bias in the upper troposphere and lower stratosphere and a consistent negative bias in the lower and middle troposphere. Holl et al. [2016], Zou et al. [2016], and Olsen et al. [2017] evaluated the data quality of the TANSO-FTS TIR V1 CH4 product through intercomparisons between TANSO-FTS and other satellite-borne and ground-based instruments; their results were generally consistent with comparison results of the V1 CH4 product with aircraft CH4 data [Saitoh et al., in preparation]. GOSAT/TANSO-FTS TIR N2O data, a by-product of the TIR V1 CH4 data, captured enhancement of N2O concentrations over the Mediterranean Sea associated with Asian monsoon circulation in spite of low signal-to-noise ratio (SNR) of TANSO-FTS 7-μm CH4 band [Kangah et al., 2017]. The SNR of the TIR bands of GOSAT-2/TANSO-FTS-2 are expected to be larger than that of TANSO-FTS especially at the 7-μm CH4 band. Based on the TANSO-FTS TIR V1 algorithm, we are now developing a retrieval algorithm for CO2, CH4, and other trace gases from the two TIR bands of GOSAT-2/TANSO-FTS-2. We have performed retrieval simulations using outputs from the Nonhydrostatic Icosahedral Atmospheric Model (NICAM)-based Transport Model (TM) [Niwa et al., 2011; 2017], which will be used as a priori data for the retrieval processing of GOSAT-2/TANSO-FTS-2.

MinD directly interacting with FtsZ at the H10 helix suggests a model for robust activation of MinC to destabilize FtsZ polymers.

PubMed

Taviti, Ashoka Chary; Beuria, Tushar Kant

2017-09-07

Cell division in bacteria is a highly controlled and regulated process. FtsZ, a bacterial cytoskeletal protein, forms a ring-like structure known as the Z-ring and recruits more than a dozen other cell division proteins. The Min system oscillates between the poles and inhibits the Z-ring formation at the poles by perturbing FtsZ assembly. This leads to an increase in the FtsZ concentration at the mid-cell and helps in Z-ring positioning. MinC, the effector protein, interferes with Z-ring formation through two different mechanisms mediated by its two domains with the help of MinD. However, the mechanism by which MinD triggers MinC activity is not yet known. We showed that MinD directly interacts with FtsZ with an affinity stronger than the reported MinC-FtsZ interaction. We determined the MinD-binding site of FtsZ using computational, mutational and biochemical analyses. Our study showed that MinD binds to the H10 helix of FtsZ. Single-point mutations at the charged residues in the H10 helix resulted in a decrease in the FtsZ affinity towards MinD. Based on our findings, we propose a novel model for MinCD-FtsZ interaction, where MinD through its direct interaction with FtsZ would trigger MinC activity to inhibit FtsZ functions. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

FtsZ ring: the eubacterial division apparatus conserved in archaebacteria.

PubMed

Wang, X; Lutkenhaus, J

1996-07-01

FtsZ is a tubulin-like protein that is essential for cell division in eubacteria. It functions by forming a ring at the division site that directs septation. The archaebacteria constitute a kingdom of life separate from eubacteria and eukaryotes. Like eubacteria, archaebacteria are prokaryotes, although they are phylogenetically closer to eukaryotes. Here it is shown that archaebacteria also possess FtsZ and that it is biochemically similar to eubacterial FtsZs. Significantly, FtsZ from the archaebacterium Haloferax volcanii is a GTPase that is localized to a ring that coincides with the division constriction. These results indicate that the FtsZ ring was part of the division apparatus of a common prokaryotic ancestor that was retained by both eubacteria and archaebacteria.

Structure of the Z Ring-associated Protein, ZapD, Bound to the C-terminal Domain of the Tubulin-like Protein, FtsZ, Suggests Mechanism of Z Ring Stabilization through FtsZ Cross-linking.

PubMed

Schumacher, Maria A; Huang, Kuo-Hsiang; Zeng, Wenjie; Janakiraman, Anuradha

2017-03-03

Cell division in most bacteria is mediated by the tubulin-like FtsZ protein, which polymerizes in a GTP-dependent manner to form the cytokinetic Z ring. A diverse repertoire of FtsZ-binding proteins affects FtsZ localization and polymerization to ensure correct Z ring formation. Many of these proteins bind the C-terminal domain (CTD) of FtsZ, which serves as a hub for FtsZ regulation. FtsZ ring-associated proteins, ZapA-D (Zaps), are important FtsZ regulatory proteins that stabilize FtsZ assembly and enhance Z ring formation by increasing lateral assembly of FtsZ protofilaments, which then form the Z ring. There are no structures of a Zap protein bound to FtsZ; therefore, how these proteins affect FtsZ polymerization has been unclear. Recent data showed ZapD binds specifically to the FtsZ CTD. Thus, to obtain insight into the ZapD-CTD interaction and how it may mediate FtsZ protofilament assembly, we determined the Escherichia coli ZapD-FtsZ CTD structure to 2.67 Å resolution. The structure shows that the CTD docks within a hydrophobic cleft in the ZapD helical domain and adopts an unusual structure composed of two turns of helix separated by a proline kink. FtsZ CTD residue Phe-377 inserts into the ZapD pocket, anchoring the CTD in place and permitting hydrophobic contacts between FtsZ residues Ile-374, Pro-375, and Leu-378 with ZapD residues Leu-74, Trp-77, Leu-91, and Leu-174. The structural findings were supported by mutagenesis coupled with biochemical and in vivo studies. The combined data suggest that ZapD acts as a molecular cross-linking reagent between FtsZ protofilaments to enhance FtsZ assembly. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Effects of rhodomyrtone on Gram-positive bacterial tubulin homologue FtsZ

PubMed Central

Saeloh, Dennapa; Wenzel, Michaela; Rungrotmongkol, Thanyada; Hamoen, Leendert Willem

2017-01-01

Rhodomyrtone, a natural antimicrobial compound, displays potent activity against many Gram-positive pathogenic bacteria, comparable to last-defence antibiotics including vancomycin and daptomycin. Our previous studies pointed towards effects of rhodomyrtone on the bacterial membrane and cell wall. In addition, a recent molecular docking study suggested that the compound could competitively bind to the main bacterial cell division protein FtsZ. In this study, we applied a computational approach (in silico), in vitro, and in vivo experiments to investigate molecular interactions of rhodomyrtone with FtsZ. Using molecular simulation, FtsZ conformational changes were observed in both (S)- and (R)-rhodomyrtone binding states, compared with the three natural states of FtsZ (ligand-free, GDP-, and GTP-binding states). Calculations of free binding energy showed a higher affinity of FtsZ to (S)-rhodomyrtone (−35.92 ± 0.36 kcal mol−1) than the GDP substrate (−23.47 ± 0.25 kcal mol−1) while less affinity was observed in the case of (R)-rhodomyrtone (−18.11 ± 0.11 kcal mol−1). In vitro experiments further revealed that rhodomyrtone reduced FtsZ polymerization by 36% and inhibited GTPase activity by up to 45%. However, the compound had no effect on FtsZ localization in Bacillus subtilis at inhibitory concentrations and cells also did not elongate after treatment. Higher concentrations of rhodomyrtone did affect localization of FtsZ and also affected localization of its membrane anchor proteins FtsA and SepF, showing that the compound did not specifically inhibit FtsZ but rather impaired multiple divisome proteins. Furthermore, a number of cells adopted a bean-like shape suggesting that rhodomyrtone possibly possesses further targets involved in cell envelope synthesis and/or maintenance. PMID:28168121

Effects of rhodomyrtone on Gram-positive bacterial tubulin homologue FtsZ.

PubMed

Saeloh, Dennapa; Wenzel, Michaela; Rungrotmongkol, Thanyada; Hamoen, Leendert Willem; Tipmanee, Varomyalin; Voravuthikunchai, Supayang Piyawan

2017-01-01

Rhodomyrtone, a natural antimicrobial compound, displays potent activity against many Gram-positive pathogenic bacteria, comparable to last-defence antibiotics including vancomycin and daptomycin. Our previous studies pointed towards effects of rhodomyrtone on the bacterial membrane and cell wall. In addition, a recent molecular docking study suggested that the compound could competitively bind to the main bacterial cell division protein FtsZ. In this study, we applied a computational approach ( in silico ), in vitro , and in vivo experiments to investigate molecular interactions of rhodomyrtone with FtsZ. Using molecular simulation, FtsZ conformational changes were observed in both (S)- and (R)-rhodomyrtone binding states, compared with the three natural states of FtsZ (ligand-free, GDP-, and GTP-binding states). Calculations of free binding energy showed a higher affinity of FtsZ to (S)-rhodomyrtone (-35.92 ± 0.36 kcal mol -1 ) than the GDP substrate (-23.47 ± 0.25 kcal mol -1 ) while less affinity was observed in the case of (R)-rhodomyrtone (-18.11 ± 0.11 kcal mol -1 ). In vitro experiments further revealed that rhodomyrtone reduced FtsZ polymerization by 36% and inhibited GTPase activity by up to 45%. However, the compound had no effect on FtsZ localization in Bacillus subtilis at inhibitory concentrations and cells also did not elongate after treatment. Higher concentrations of rhodomyrtone did affect localization of FtsZ and also affected localization of its membrane anchor proteins FtsA and SepF, showing that the compound did not specifically inhibit FtsZ but rather impaired multiple divisome proteins. Furthermore, a number of cells adopted a bean-like shape suggesting that rhodomyrtone possibly possesses further targets involved in cell envelope synthesis and/or maintenance.

Lessons from bacterial homolog of tubulin, FtsZ for microtubule dynamics.

PubMed

Battaje, Rachana Rao; Panda, Dulal

2017-09-01

FtsZ, a homolog of tubulin, is found in almost all bacteria and archaea where it has a primary role in cytokinesis. Evidence for structural homology between FtsZ and tubulin came from their crystal structures and identification of the GTP box. Tubulin and FtsZ constitute a distinct family of GTPases and show striking similarities in many of their polymerization properties. The differences between them, more so, the complexities of microtubule dynamic behavior in comparison to that of FtsZ, indicate that the evolution to tubulin is attributable to the incorporation of the complex functionalities in higher organisms. FtsZ and microtubules function as polymers in cell division but their roles differ in the division process. The structural and partial functional homology has made the study of their dynamic properties more interesting. In this review, we focus on the application of the information derived from studies on FtsZ dynamics to study microtubule dynamics and vice versa. The structural and functional aspects that led to the establishment of the homology between the two proteins are explained to emphasize the network of FtsZ and microtubule studies and how they are connected. © 2017 Society for Endocrinology.

Robotic technologies of the Flight Telerobotic Servicer (FTS) including fault tolerance

NASA Technical Reports Server (NTRS)

Chladek, John T.; Craver, William M.

1994-01-01

The original FTS concept for Space Station Freedom (SSF) was to provide telerobotic assistance to enhance crew activity and safety and to reduce crew EVA (Extra Vehicular Activity) activity. The first flight of the FTS manipulator systems would demonstrate several candidate tasks and would verify manipulator performance parameters. These first flight tasks included unlocking a SSF Truss Joint, mating/demating a fluid coupling, contact following of a contour board, demonstrating peg-in-hole assembly, and grasping and moving a mass. Future tasks foreseen for the FTS system included ORU (Orbit Replaceable Unit) change-out, Hubble Space Telescope Servicing, Gamma Ray Observatory refueling, and several in-situ SSF servicing and maintenance tasks. Operation of the FTS was planned to evolve from teleoperation to fully autonomous execution of many tasks. This wide range of mission tasks combined with the desire to evolve toward fully autonomy forced several requirements which may seen extremely demanding to the telerobotics community. The FTS requirements appear to have been created to accommodate the open-ended evolution plan such that operational evolution would not be impeded by function limitations. A recommendation arising from the FTS program to remedy the possible impacts from such ambitious requirements is to analyze candidate robotic tasks. Based on these task analyses, operational impacts against development impacts were weighed prior to requirements definition. Many of the FTS requirements discussed in the following sections greatly influenced the development cost and schedule of the FTS manipulator. The FTS manipulator has been assembled at Martin Marietta and is currently in testing. Successful component tests indicate a manipulator which achieves unprecedented performance specifications.

Dynamic FtsA and FtsZ localization and outer membrane alterations during polar growth and cell division in Agrobacterium tumefaciens

PubMed Central

Zupan, John R.; Cameron, Todd A.; Anderson-Furgeson, James; Zambryski, Patricia C.

2013-01-01

Growth and cell division in rod-shaped bacteria have been primarily studied in species that grow predominantly by peptidoglycan (PG) synthesis along the length of the cell. Rhizobiales species, however, predominantly grow by PG synthesis at a single pole. Here we characterize the dynamic localization of several Agrobacterium tumefaciens components during the cell cycle. First, the lipophilic dye FM 4-64 predominantly stains the outer membranes of old poles versus growing poles. In cells about to divide, however, both poles are equally labeled with FM 4-64, but the constriction site is not. Second, the cell-division protein FtsA alternates from unipolar foci in the shortest cells to unipolar and midcell localization in cells of intermediate length, to strictly midcell localization in the longest cells undergoing septation. Third, the cell division protein FtsZ localizes in a cell-cycle pattern similar to, but more complex than, FtsA. Finally, because PG synthesis is spatially and temporally regulated during the cell cycle, we treated cells with sublethal concentrations of carbenicillin (Cb) to assess the role of penicillin-binding proteins in growth and cell division. Cb-treated cells formed midcell circumferential bulges, suggesting that interrupted PG synthesis destabilizes the septum. Midcell bulges contained bands or foci of FtsA-GFP and FtsZ-GFP and no FM 4-64 label, as in untreated cells. There were no abnormal morphologies at the growth poles in Cb-treated cells, suggesting unipolar growth uses Cb-insensitive PG synthesis enzymes. PMID:23674672

Protein quality control in organelles - AAA/FtsH story.

PubMed

Janska, Hanna; Kwasniak, Malgorzata; Szczepanowska, Joanna

2013-02-01

This review focuses on organellar AAA/FtsH proteases, whose proteolytic and chaperone-like activity is a crucial component of the protein quality control systems of mitochondrial and chloroplast membranes. We compare the AAA/FtsH proteases from yeast, mammals and plants. The nature of the complexes formed by AAA/FtsH proteases and the current view on their involvement in degradation of non-native organellar proteins or assembly of membrane complexes are discussed. Additional functions of AAA proteases not directly connected with protein quality control found in yeast and mammals but not yet in plants are also described shortly. Following an overview of the molecular functions of the AAA/FtsH proteases we discuss physiological consequences of their inactivation in yeast, mammals and plants. The molecular basis of phenotypes associated with inactivation of the AAA/FtsH proteases is not fully understood yet, with the notable exception of those observed in m-AAA protease-deficient yeast cells, which are caused by impaired maturation of mitochondrial ribosomal protein. Finally, examples of cytosolic events affecting protein quality control in mitochondria and chloroplasts are given. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids. Copyright © 2012 Elsevier B.V. All rights reserved.

The Hetero-Hexameric Nature of a Chloroplast AAA+ FtsH Protease Contributes to Its Thermodynamic Stability

PubMed Central

Ziv, Tamar; Adam, Zach; Prag, Gali

2012-01-01

FtsH is an evolutionary conserved membrane-bound metalloprotease complex. While in most prokaryotes FtsH is encoded by a single gene, multiple FtsH genes are found in eukaryotes. Genetic and biochemical data suggest that the Arabidopsis chloroplast FtsH is a hetero-hexamer. This raises the question why photosynthetic organisms require a heteromeric complex, whereas in most bacteria a homomeric one is sufficient. To gain structural information of the possible complexes, the Arabidopsis FtsH2 (type B) and FtsH5 (type A) were modeled. An in silico study with mixed models of FtsH2/5 suggests that heteromeric hexamer structure with ratio of 4∶2 is more likely to exists. Specifically, calculation of the buried surface area at the interfaces between neighboring subunits revealed that a hetero-complex should be thermodynamically more stable than a homo-hexamer, due to the presence of additional hydrophobic and hydrophilic interactions. To biochemically assess this model, we generated Arabidopsis transgenic plants, expressing epitope-tagged FtsH2 and immuno-purified the protein. Mass-spectrometry analysis showed that FtsH2 is associated with FtsH1, FtsH5 and FtsH8. Interestingly, we found that ‘type B’ subunits (FtsH2 and FtsH8) were 2–3 fold more abundant than ‘type A’ (FtsH1 and FtsH5). The biochemical data corroborate the in silico model and suggest that the thylakoid FtsH hexamer is composed of two ‘type A’ and four ‘type B’ subunits. PMID:22558304

Location of Dual Sites in E. coli FtsZ Important for Degradation by ClpXP; One at the C-Terminus and One in the Disordered Linker

PubMed Central

Camberg, Jodi L.; Viola, Marissa G.; Rea, Leslie; Hoskins, Joel R.; Wickner, Sue

2014-01-01

ClpXP is a two-component ATP-dependent protease that unfolds and degrades proteins bearing specific recognition signals. One substrate degraded by Escherichia coli ClpXP is FtsZ, an essential cell division protein. FtsZ forms polymers that assemble into a large ring-like structure, termed the Z-ring, during cell division at the site of constriction. The FtsZ monomer is composed of an N-terminal polymerization domain, an unstructured linker region and a C-terminal conserved region. To better understand substrate selection by ClpXP, we engineered FtsZ mutant proteins containing amino acid substitutions or deletions near the FtsZ C-terminus. We identified two discrete regions of FtsZ important for degradation of both FtsZ monomers and polymers by ClpXP in vitro. One region is located 30 residues away from the C-terminus in the unstructured linker region that connects the polymerization domain to the C-terminal region. The other region is near the FtsZ C-terminus and partially overlaps the recognition sites for several other FtsZ-interacting proteins, including MinC, ZipA and FtsA. Mutation of either region caused the protein to be more stable and mutation of both caused an additive effect, suggesting that both regions are important. We also observed that in vitro MinC inhibits degradation of FtsZ by ClpXP, suggesting that some of the same residues in the C-terminal site that are important for degradation by ClpXP are important for binding MinC. PMID:24722340

A specific role for the ZipA protein in cell division: stabilization of the FtsZ protein.

PubMed

Pazos, Manuel; Natale, Paolo; Vicente, Miguel

2013-02-01

In Escherichia coli, the cell division protein FtsZ is anchored to the cytoplasmic membrane by the action of the bitopic membrane protein ZipA and the cytoplasmic protein FtsA. Although the presence of both ZipA and FtsA is strictly indispensable for cell division, an FtsA gain-of-function mutant FtsA* (R286W) can bypass the ZipA requirement for cell division. This observation casts doubts on the role of ZipA and its need for cell division. Maxicells are nucleoid-free bacterial cells used as a whole cell in vitro system to probe protein-protein interactions without the need of protein purification. We show that ZipA protects FtsZ from the ClpXP-directed degradation observed in E. coli maxicells and that ZipA-stabilized FtsZ forms membrane-attached spiral-like structures in the bacterial cytoplasm. The overproduction of the FtsZ-binding ZipA domain is sufficient to protect FtsZ from degradation, whereas other C-terminal ZipA partial deletions lacking it are not. Individual overproduction of the proto-ring component FtsA or its gain-of-function mutant FtsA* does not result in FtsZ protection. Overproduction of FtsA or FtsA* together with ZipA does not interfere with the FtsZ protection. Moreover, neither FtsA nor FtsA* protects FtsZ when overproduced together with ZipA mutants lacking the FZB domain. We propose that ZipA protects FtsZ from degradation by ClpP by making the FtsZ site of interaction unavailable to the ClpX moiety of the ClpXP protease. This role cannot be replaced by either FtsA or FtsA*, suggesting a unique function for ZipA in proto-ring stability.

Comparison of the GOSAT TANSO-FTS TIR CH volume mixing ratio vertical profiles with those measured by ACE-FTS, ESA MIPAS, IMK-IAA MIPAS, and 16 NDACC stations

NASA Astrophysics Data System (ADS)

Olsen, Kevin S.; Strong, Kimberly; Walker, Kaley A.; Boone, Chris D.; Raspollini, Piera; Plieninger, Johannes; Bader, Whitney; Conway, Stephanie; Grutter, Michel; Hannigan, James W.; Hase, Frank; Jones, Nicholas; de Mazière, Martine; Notholt, Justus; Schneider, Matthias; Smale, Dan; Sussmann, Ralf; Saitoh, Naoko

2017-10-01

The primary instrument on the Greenhouse gases Observing SATellite (GOSAT) is the Thermal And Near infrared Sensor for carbon Observations (TANSO) Fourier transform spectrometer (FTS). TANSO-FTS uses three short-wave infrared (SWIR) bands to retrieve total columns of CO2 and CH4 along its optical line of sight and one thermal infrared (TIR) channel to retrieve vertical profiles of CO2 and CH4 volume mixing ratios (VMRs) in the troposphere. We examine version 1 of the TANSO-FTS TIR CH4 product by comparing co-located CH4 VMR vertical profiles from two other remote-sensing FTS systems: the Canadian Space Agency's Atmospheric Chemistry Experiment FTS (ACE-FTS) on SCISAT (version 3.5) and the European Space Agency's Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat (ESA ML2PP version 6 and IMK-IAA reduced-resolution version V5R_CH4_224/225), as well as 16 ground stations with the Network for the Detection of Atmospheric Composition Change (NDACC). This work follows an initial inter-comparison study over the Arctic, which incorporated a ground-based FTS at the Polar Environment Atmospheric Research Laboratory (PEARL) at Eureka, Canada, and focuses on tropospheric and lower-stratospheric measurements made at middle and tropical latitudes between 2009 and 2013 (mid-2012 for MIPAS). For comparison, vertical profiles from all instruments are interpolated onto a common pressure grid, and smoothing is applied to ACE-FTS, MIPAS, and NDACC vertical profiles. Smoothing is needed to account for differences between the vertical resolution of each instrument and differences in the dependence on a priori profiles. The smoothing operators use the TANSO-FTS a priori and averaging kernels in all cases. We present zonally averaged mean CH4 differences between each instrument and TANSO-FTS with and without smoothing, and we examine their information content, their sensitive altitude range, their correlation, their a priori dependence, and the variability within

Commissioning of the FTS-2 Data Reduction Pipeline

NASA Astrophysics Data System (ADS)

Sherwood, M.; Naylor, D.; Gom, B.; Bell, G.; Friberg, P.; Bintley, D.

2015-09-01

FTS-2 is the intermediate resolution Fourier Transform Spectrometer coupled to the SCUBA-2 facility bolometer camera at the James Clerk Maxwell Telescope in Hawaii. Although in principle FTS instruments have the advantage of relatively simple optics compared to other spectrometers, they require more sophisticated data processing to compute spectra from the recorded interferogram signal. In the case of FTS-2, the complicated optical design required to interface with the existing telescope optics introduces performance compromises that complicate spectral and spatial calibration, and the response of the SCUBA-2 arrays introduce interferogram distortions that are a challenge for data reduction algorithms. We present an overview of the pipeline and discuss new algorithms that have been written to correct the noise introduced by unexpected behavior of the SCUBA-2 arrays.

Effective GTP-replacing FtsZ inhibitors and antibacterial mechanism of action.

PubMed

Artola, Marta; Ruiz-Avila, Laura B; Vergoñós, Albert; Huecas, Sonia; Araujo-Bazán, Lidia; Martín-Fontecha, Mar; Vázquez-Villa, Henar; Turrado, Carlos; Ramírez-Aportela, Erney; Hoegl, Annabelle; Nodwell, Matthew; Barasoain, Isabel; Chacón, Pablo; Sieber, Stephan A; Andreu, Jose M; López-Rodríguez, María L

2015-03-20

Essential cell division protein FtsZ is considered an attractive target in the search for antibacterials with novel mechanisms of action to overcome the resistance problem. FtsZ undergoes GTP-dependent assembly at midcell to form the Z-ring, a dynamic structure that evolves until final constriction of the cell. Therefore, molecules able to inhibit its activity will eventually disrupt bacterial viability. In this work, we report a new series of small molecules able to replace GTP and to specifically inhibit FtsZ, blocking the bacterial division process. These new synthesized inhibitors interact with the GTP-binding site of FtsZ (Kd = 0.4-0.8 μM), display antibacterial activity against Gram-positive pathogenic bacteria, and show selectivity against tubulin. Biphenyl derivative 28 stands out as a potent FtsZ inhibitor (Kd = 0.5 μM) with high antibacterial activity [MIC (MRSA) = 7 μM]. In-depth analysis of the mechanism of action of compounds 22, 28, 33, and 36 has revealed that they act as effective inhibitors of correct FtsZ assembly, blocking bacterial division and thus leading to filamentous undivided cells. These findings provide a compelling rationale for the development of compounds targeting the GTP-binding site as antibacterial agents and open the door to antibiotics with novel mechanisms of action.

Molecular evolution of FtsZ protein sequences encoded within the genomes of archaea, bacteria, and eukaryota.

PubMed

Vaughan, Sue; Wickstead, Bill; Gull, Keith; Addinall, Stephen G

2004-01-01

The FtsZ protein is a polymer-forming GTPase which drives bacterial cell division and is structurally and functionally related to eukaryotic tubulins. We have searched for FtsZ-related sequences in all freely accessible databases, then used strict criteria based on the tertiary structure of FtsZ and its well-characterized in vitro and in vivo properties to determine which sequences represent genuine homologues of FtsZ. We have identified 225 full-length FtsZ homologues, which we have used to document, phylum by phylum, the primary sequence characteristics of FtsZ homologues from the Bacteria, Archaea, and Eukaryota. We provide evidence for at least five independent ftsZ gene-duplication events in the bacterial kingdom and suggest the existence of three ancestoral euryarchaeal FtsZ paralogues. In addition, we identify "FtsZ-like" sequences from Bacteria and Archaea that, while showing significant sequence similarity to FtsZs, are unlikely to bind and hydrolyze GTP.

A novel membrane anchor for FtsZ is linked to cell wall hydrolysis in Caulobacter crescentus.

PubMed

Meier, Elizabeth L; Razavi, Shiva; Inoue, Takanari; Goley, Erin D

2016-07-01

In most bacteria, the tubulin-like GTPase FtsZ forms an annulus at midcell (the Z-ring) which recruits the division machinery and regulates cell wall remodeling. Although both activities require membrane attachment of FtsZ, few membrane anchors have been characterized. FtsA is considered to be the primary membrane tether for FtsZ in bacteria, however in Caulobacter crescentus, FtsA arrives at midcell after stable Z-ring assembly and early FtsZ-directed cell wall synthesis. We hypothesized that additional proteins tether FtsZ to the membrane and demonstrate that in C. crescentus, FzlC is one such membrane anchor. FzlC associates with membranes directly in vivo and in vitro and recruits FtsZ to membranes in vitro. As for most known membrane anchors, the C-terminal peptide of FtsZ is required for its recruitment to membranes by FzlC in vitro and midcell recruitment of FzlC in cells. In vivo, overproduction of FzlC causes cytokinesis defects whereas deletion of fzlC causes synthetic defects with dipM, ftsE and amiC mutants, implicating FzlC in cell wall hydrolysis. Our characterization of FzlC as a novel membrane anchor for FtsZ expands our understanding of FtsZ regulators and establishes a role for membrane-anchored FtsZ in the regulation of cell wall hydrolysis. © 2016 John Wiley & Sons Ltd.

Improved ACE-FTS observations of carbon tetrachloride (CCl4)

NASA Astrophysics Data System (ADS)

Harrison, Jeremy; Chipperfield, Martyn; Boone, Chris; Bernath, Peter

2016-04-01

The Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS), on board the SCISAT satellite, has been recording solar occultation spectra through the Earth's atmosphere since 2004 and continues to take measurements with only minor loss in performance. ACE-FTS time series are available for a range of chlorine 'source' gases, including CCl3F (CFC-11), CCl2F2 (CFC-12), CHF2Cl (HCFC-22), CH3Cl and CCl4. Recently there has been much community interest in carbon tetrachloride (CCl4), a substance regulated by the Montreal Protocol because it leads to the catalytic destruction of stratospheric ozone. Estimated sources and sinks of CCl4 remain inconsistent with observations of its abundance. Satellite observations of CCl4 in the stratosphere are particularly useful in validating stratospheric loss (photolysis) rates; in fact the atmospheric loss of CCl4 is essentially all due to photolysis in the stratosphere. However, the latest ACE-FTS v3.5 CCl4 retrieval is biased high by ˜ 20-30%. A new ACE-FTS retrieval scheme utilising new laboratory spectroscopic measurements of CCl4 and improved microwindow selection has recently been developed. This improves upon the v3.5 retrieval and resolves the issue of the high bias; this new scheme will form the basis for the upcoming v4 processing version of ACE-FTS data. This presentation will outline the improvements made in the retrieval, and a subset of data will be compared with modelled CCl4 distributions from SLIMCAT, a state-of-the-art three-dimensional chemical transport model. The use of ACE-FTS data to evaluate the modelled stratospheric loss rate of CCl4 will also be discussed. The evaluated model, which also includes a treatment of surface soil and ocean sinks, will then be used to quantify current uncertainties in the global budget of CCl4.

LexA Binds to Transcription Regulatory Site of Cell Division Gene ftsZ in Toxic Cyanobacterium Microcystis aeruginosa.

PubMed

Honda, Takashi; Morimoto, Daichi; Sako, Yoshihiko; Yoshida, Takashi

2018-05-17

Previously, we showed that DNA replication and cell division in toxic cyanobacterium Microcystis aeruginosa are coordinated by transcriptional regulation of cell division gene ftsZ and that an unknown protein specifically bound upstream of ftsZ (BpFz; DNA-binding protein to an upstream site of ftsZ) during successful DNA replication and cell division. Here, we purified BpFz from M. aeruginosa strain NIES-298 using DNA-affinity chromatography and gel-slicing combined with gel electrophoresis mobility shift assay (EMSA). The N-terminal amino acid sequence of BpFz was identified as TNLESLTQ, which was identical to that of transcription repressor LexA from NIES-843. EMSA analysis using mutant probes showed that the sequence GTACTAN 3 GTGTTC was important in LexA binding. Comparison of the upstream regions of lexA in the genomes of closely related cyanobacteria suggested that the sequence TASTRNNNNTGTWC could be a putative LexA recognition sequence (LexA box). Searches for TASTRNNNNTGTWC as a transcriptional regulatory site (TRS) in the genome of M. aeruginosa NIES-843 showed that it was present in genes involved in cell division, photosynthesis, and extracellular polysaccharide biosynthesis. Considering that BpFz binds to the TRS of ftsZ during normal cell division, LexA may function as a transcriptional activator of genes related to cell reproduction in M. aeruginosa, including ftsZ. This may be an example of informality in the control of bacterial cell division.

Differential impacts of FtsZ proteins on plastid division in the shoot apex of Arabidopsis.

PubMed

Swid, Neora; Nevo, Reinat; Kiss, Vladimir; Kapon, Ruti; Dagan, Shlomi; Snir, Orli; Adam, Zach; Falconet, Denis; Reich, Ziv; Charuvi, Dana

2018-06-16

FtsZ proteins of the FtsZ1 and FtsZ2 families play important roles in the initiation and progression of plastid division in plants and green algae. Arabidopsis possesses a single FTSZ1 member and two FTSZ2 members, FTSZ2-1 and FTSZ2-2. The contribution of these to chloroplast division and partitioning has been mostly investigated in leaf mesophyll tissues. Here, we assessed the involvement of the three FtsZs in plastid division at earlier stages of chloroplast differentiation. To this end, we studied the effect of the absence of specific FtsZ proteins on plastids in the vegetative shoot apex, where the proplastid-to-chloroplast transition takes place. We found that the relative contribution of the two major leaf FtsZ isoforms, FtsZ1 and FtsZ2-1, to the division process varies with cell lineage and position within the shoot apex. While FtsZ2-1 dominates division in the L1 and L3 layers of the shoot apical meristem (SAM), in the L2 layer, FtsZ1 and FtsZ2-1 contribute equally toward the process. Depletion of the third isoform, FtsZ2-2, generally resulted in stronger effects in the shoot apex than those observed in mature leaves. The implications of these findings, along with additional observations made in this work, to our understanding of the mechanisms and regulation of plastid proliferation in the shoot apex are discussed. Copyright © 2018. Published by Elsevier Inc.

SCIAMACHY and FTS CO2 Retrievals Using the OCO Retrieval Algorithm

NASA Technical Reports Server (NTRS)

Boesch, Hartmut; Buchwitz, M.; Sen, Bhaswar; Toon, Geoffrey C.; Washenfelder, Rebecca A.; Wennberg, Paul O.

2005-01-01

The Orbiting Carbon Observatory (OCO) mission will make the first global, space-based measurements of atmospheric C02 with the precision and coverage needed to characterize C02 sources and sinks on regional scales. OCO will make spectrally and spatially highly resolved measurements of reflected sunlight in the 02A -band and two near-infrared C02 bands. To test the OCO retrieval algorithm, SCIAMACHY and ground-based Fourier Transform Spectrometer (FTS) measurements at Park Falls, Wisconsin have been analyzed. Good agreement between SCIAMACHY and FTS C02 columns has been found with SCIAMACHY showing a much larger scatter than FTS measurements. Both SCIAMACHY and FTS overestimate the surface pressure by a few percent which significantly impacts retrieved C02 columns.

Differential effect of mutational impairment of penicillin-binding proteins 1A and 1B on Escherichia coli strains harboring thermosensitive mutations in the cell division genes ftsA, ftsQ, ftsZ, and pbpB.

PubMed Central

García del Portillo, F; de Pedro, M A

1990-01-01

To study the functional differences between penicillin-binding proteins (PBPs) 1A and 1B, as well as their recently postulated involvement in the septation process (F. García del Portillo, M. A. de Pedro, D. Joseleau-Petit, and R. D'Ari, J. Bacteriol. 171:4217-4221, 1989), a series of isogenic strains with mutations in the genes coding for PBP 1A (ponA) or PBP 1B (ponB) or in the cell division-specific genes ftsA, ftsQ, pbpB, and ftsZ was constructed and used as the start point to produce double mutants combining the ponA or ponB characters with mutations in cell division genes. PBP 1A seemed to be unable to preserve cell integrity by itself, requiring the additional activities of PBP 2, PBP 3, and FtsQ. PBP 1B was apparently endowed with a more versatile biosynthetic potential that permitted a substantial enlargement of PBP 1A-deficient cells when PBP 2 or 3 was inhibited or when FtsQ was inactive. beta-Lactams binding to PBP 2 (mecillinam) or 3 (furazlocillin) caused rapid lysis in a ponB background. The lytic effect of furazlocillin to ponB cell division double mutants was suppressed at the restrictive temperature irrespective of the identity of the mutated cell division gene. These results indicate that PBPs 1A and 1B play distinct roles in cell wall synthesis and support the idea of a relevant involvement of PBP 1B in peptidoglycan synthesis at the time of septation. Images PMID:2211517

Isolation, Characterization and Lipid-Binding Properties of the Recalcitrant FtsA Division Protein from Escherichia coli

PubMed Central

Zorrilla, Silvia; Reija, Belén; Alfonso, Carlos; Mingorance, Jesús; Rivas, Germán; Jiménez, Mercedes

2012-01-01

We have obtained milligram amounts of highly pure Escherichia coli division protein FtsA from inclusion bodies with an optimized purification method that, by overcoming the reluctance of FtsA to be purified, surmounts a bottleneck for the analysis of the molecular basis of FtsA function. Purified FtsA is folded, mostly monomeric and interacts with lipids. The apparent affinity of FtsA binding to the inner membrane is ten-fold higher than to phospholipids, suggesting that inner membrane proteins could modulate FtsA-membrane interactions. Binding of FtsA to lipids and membranes is insensitive to ionic strength, indicating that a net contribution of hydrophobic interactions is involved in the association of FtsA to lipid/membrane structures. PMID:22761913

Synthetic inhibitors of bacterial cell division targeting the GTP-binding site of FtsZ.

PubMed

Ruiz-Avila, Laura B; Huecas, Sonia; Artola, Marta; Vergoñós, Albert; Ramírez-Aportela, Erney; Cercenado, Emilia; Barasoain, Isabel; Vázquez-Villa, Henar; Martín-Fontecha, Mar; Chacón, Pablo; López-Rodríguez, María L; Andreu, José M

2013-09-20

Cell division protein FtsZ is the organizer of the cytokinetic Z-ring in most bacteria and a target for new antibiotics. FtsZ assembles with GTP into filaments that hydrolyze the nucleotide at the association interface between monomers and then disassemble. We have replaced FtsZ's GTP with non-nucleotide synthetic inhibitors of bacterial division. We searched for these small molecules among compounds from the literature, from virtual screening (VS), and from our in-house synthetic library (UCM), employing a fluorescence anisotropy primary assay. From these screens we have identified the polyhydroxy aromatic compound UCM05 and its simplified analogue UCM44 that specifically bind to Bacillus subtilis FtsZ monomers with micromolar affinities and perturb normal assembly, as examined with light scattering, polymer sedimentation, and negative stain electron microscopy. On the other hand, these ligands induce the cooperative assembly of nucleotide-devoid archaeal FtsZ into distinct well-ordered polymers, different from GTP-induced filaments. These FtsZ inhibitors impair localization of FtsZ into the Z-ring and inhibit bacterial cell division. The chlorinated analogue UCM53 inhibits the growth of clinical isolates of antibiotic-resistant Staphylococcus aureus and Enterococcus faecalis. We suggest that these interfacial inhibitors recapitulate binding and some assembly-inducing effects of GTP but impair the correct structural dynamics of FtsZ filaments and thus inhibit bacterial division, possibly by binding to a small fraction of the FtsZ molecules in a bacterial cell, which opens a new approach to FtsZ-based antibacterial drug discovery.

BT-benzo-29 inhibits bacterial cell proliferation by perturbing FtsZ assembly.

PubMed

Ray, Shashikant; Jindal, Bhavya; Kunal, Kishore; Surolia, Avadhesha; Panda, Dulal

2015-10-01

We have identified a potent antibacterial agent N-(4-sec-butylphenyl)-2-(thiophen-2-yl)-1H-benzo[d]imidazole-4-carboxamide (BT-benzo-29) from a library of benzimidazole derivatives that stalled bacterial division by inhibiting FtsZ assembly. A short (5 min) exposure of BT-benzo-29 disassembled the cytokinetic Z-ring in Bacillus subtilis cells without affecting the cell length and nucleoids. BT-benzo-29 also perturbed the localization of early and late division proteins such as FtsA, ZapA and SepF at the mid-cell. Further, BT-benzo-29 bound to FtsZ with a dissociation constant of 24 ± 3 μm and inhibited the assembly and GTPase activity of purified FtsZ. A docking analysis suggested that BT-benzo-29 may bind to FtsZ at the C-terminal domain near the T7 loop. BT-benzo-29 displayed significantly weaker inhibitory effects on the assembly and GTPase activity of two mutants (L272A and V275A) of FtsZ supporting the prediction of the docking analysis. Further, BT-benzo-29 did not appear to inhibit DNA duplication and nucleoid segregation and it did not perturb the membrane potential of B. subtilis cells. The results suggested that BT-benzo-29 exerts its potent antibacterial activity by inhibiting FtsZ assembly. Interestingly, BT-benzo-29 did not affect the membrane integrity of mammalian red blood cells. BT-benzo-29 bound to tubulin with a much weaker affinity than FtsZ and exerted significantly weaker effects on mammalian cells than on the bacterial cells indicating that the compound may have a strong antibacterial potential. © 2015 FEBS.

A Bactericidal Guanidinomethyl Biaryl That Alters the Dynamics of Bacterial FtsZ Polymerization

PubMed Central

Kaul, Malvika; Parhi, Ajit K.; Zhang, Yongzheng; LaVoie, Edmond J.; Tuske, Steve; Arnold, Eddy; Kerrigan, John E.; Pilch, Daniel S.

2014-01-01

The prevalence of multidrug resistance among clinically significant bacterial pathogens underscores a critical need for the development of new classes of antibiotics with novel mechanisms of action. Here we describe the synthesis and evaluation of a guanidinomethyl biaryl compound {1-((4′-(tert-butyl)-[1,1′-biphenyl]-3-yl)methyl)guanidine} that targets the bacterial cell division protein FtsZ. In vitro studies with various bacterial FtsZ proteins reveal that the compound alters the dynamics of FtsZ self-polymerization via a stimulatory mechanism, while minimally impacting the polymerization of tubulin, the closest mammalian homologue of FtsZ. The FtsZ binding site of the compound is identified through a combination of computational and mutational approaches. The compound exhibits a broad spectrum of bactericidal activity, including activity against the multidrug-resistant pathogens methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE), while also exhibiting a minimal potential to induce resistance. Taken together, our results highlight the compound as a promising new FtsZ-targeting bactericidal agent. PMID:23050700

Genetic and Biochemical Characterization of the MinC-FtsZ Interaction in Bacillus subtilis

PubMed Central

Castellen, Patricia; Nogueira, Maria Luiza C.; Bettini, Jefferson; Portugal, Rodrigo V.; Zeri, Ana Carolina M.; Gueiros-Filho, Frederico J.

2013-01-01

Cell division in bacteria is regulated by proteins that interact with FtsZ and modulate its ability to polymerize into the Z ring structure. The best studied of these regulators is MinC, an inhibitor of FtsZ polymerization that plays a crucial role in the spatial control of Z ring formation. Recent work established that E. coli MinC interacts with two regions of FtsZ, the bottom face of the H10 helix and the extreme C-terminal peptide (CTP). Here we determined the binding site for MinC on Bacillus subtilis FtsZ. Selection of a library of FtsZ mutants for survival in the presence of Min overexpression resulted in the isolation of 13 Min-resistant mutants. Most of the substitutions that gave rise to Min resistance clustered around the H9 and H10 helices in the C-terminal domain of FtsZ. In addition, a mutation in the CTP of B. subtilis FtsZ also produced MinC resistance. Biochemical characterization of some of the mutant proteins showed that they exhibited normal polymerization properties but reduced interaction with MinC, as expected for binding site mutations. Thus, our study shows that the overall architecture of the MinC-FtsZ interaction is conserved in E. coli and B. subtilis. Nevertheless, there was a clear difference in the mutations that conferred Min resistance, with those in B. subtilis FtsZ pointing to the side of the molecule rather than to its polymerization interface. This observation suggests that the mechanism of Z ring inhibition by MinC differs in both species. PMID:23577149

Chloroquine synergizes with FTS to enhance cell growth inhibition and cell death

PubMed Central

Schmukler, Eran; Wolfson, Eya; Haklai, Roni; Elad-Sfadia, Galit; Kloog, Yoel; Pinkas-Kramarski, Ronit

2014-01-01

The Ras family of small GTPases transmits extracellular signals that regulate cell growth, differentiation, motility and death. Ras signaling is constitutively active in a large number of human cancers. Ras can also regulate autophagy by affecting several signaling pathways including the mTOR pathway. Autophagy is a process that regulates the balance between protein synthesis and protein degradation. It is important for normal growth control, but may be defective in diseases. Previously, we have shown that Ras inhibition by FTS induces autophagy, which partially protects cancer cells and may limit the use of FTS as an anti-cancer drug. Since FTS is a non toxic drug we hypothesized that FTS and chloroquine (an autophagy inhibitor) will synergize in cell growth inhibition and cell death. Thus, in the present study, we explored the mechanism of each individual drug and their combined action. Our results demonstrate that in HCT-116 and in Panc-1 cells, FTS induces autophagy, which can be inhibited by chloroquine. Furthermore, the combined treatment synergistically decreased the number of viable cells. Interestingly, the combined treatment enhanced apoptotic cell death as indicated by increased sub-G1 cell population, increased Hoechst staining, activation of caspase 3, decrease in survivin expression and release of cytochrome c. Thus, chloroquine treatment may promote FTS-mediated inhibition of tumor cell growth and may stimulate apoptotic cell death. PMID:24368422

Characterization and chromosomal organization of the murD-murC-ftsQ region of Corynebacterium glutamicum ATCC 13869.

PubMed

Ramos, Angelina; Honrubia, Maria P; Vega, Daniel; Ayala, Juan A; Bouhss, Ahmed; Mengin-Lecreulx, Dominique; Gil, José A

2004-04-01

The sequence of a 4.6-kb region of DNA from Corynebacterium glutamicum ATCC 13869 lying upstream from the ftsQ-ftsZ region has been determined. The region contains four genes with high similarity to the murD, ftsW, murG, and murC genes from different microorganisms. The products of these mur genes probably catalyse several steps in the formation of the precursors for peptidoglycan synthesis in C. glutamicum, whereas ftsW might play also a role in the stabilisation of the FtsZ ring during cell division. The murC gene product was purified to near homogeneity and its UDP-N-acetylmuramate: L-alanine adding activity was demonstrated. Northern analysis indicated that ftsW, murG and ftsQ are poorly expressed in C. glutamicum whereas murC and ftsZ are expressed at higher levels at the beginning of the exponential phase. Dicistronic (ftsQ-ftsZ) and monocistronic (murC and ftsZ) transcripts can be detected using specific probes and are in agreement with the lack of transcriptional terminators in the partially analysed dcw cluster. Disruption experiments performed in C. glutamicum using internal fragments of the ftsW, murG and murC genes allowed us to conclude that FtsW, MurG, and MurC are essential gene products in C. glutamicum.

Thymic hormone containing cells. II. Evolution of cells containing the serum thymic factor (FTS or thymulin) in normal and autoimmune mice, as revealed by anti-FTS monoclonal antibodies. Relationship with Ia bearing cells.

PubMed Central

Savino, W; Dardenne, M; Bach, J F

1983-01-01

The number of thymic epithelial cells containing the serum thymic factor (FTS or thymulin), assessed by indirect immunofluorescence using an anti-FTS monoclonal antibody, was studied in the thymus of normal and autoimmune mice as a function of age. In normal mice the number of FTS+ cells was constant until the age of 6 months and then began to decline. In autoimmune strains, the age linked decline was premature being already significant at 10 weeks of age. These findings were paralleled by the age associated decline of FTS blood levels in all strains studied. Double labelling experiments showed that in both normal and autoimmune mice, FTS+ cells were Ia negative, suggesting that these cells belong to a specific subpopulation of the thymic epithelial reticulum. PMID:6345030

Plumbagin inhibits cytokinesis in Bacillus subtilis by inhibiting FtsZ assembly--a mechanistic study of its antibacterial activity.

PubMed

Bhattacharya, Anusri; Jindal, Bhavya; Singh, Parminder; Datta, Anindya; Panda, Dulal

2013-09-01

The assembly of FtsZ plays a central role in construction of the cytokinetic Z-ring that orchestrates bacterial cell division. A naturally occurring naphthoquinone, plumbagin, is known to exhibit antibacterial properties against several types of bacteria. In this study, plumbagin was found to perturb formation of the Z-ring in Bacillus subtilis 168 cells and to cause elongation of these cells without an apparent effect on nucleoid segregation, indicating that it may inhibit FtsZ assembly. Furthermore, it bound to purified B. subtilis FtsZ (BsFtsZ) with a dissociation constant of 20.7 ± 5.6 μM, and inhibited the assembly and GTPase activity of BsFtsZ in vitro. Interestingly, plumbagin did not inhibit either the assembly or GTPase activity of Escherichia coli FtsZ (EcFtsZ) in vitro. Using docking analysis, a putative plumbagin-binding site on BsFtsZ was identified, and the analysis indicated that hydrophobic interactions and hydrogen bonds predominate. Based on the in silico analysis, two variants of BsFtsZ, namely D199A and V307R, were constructed to explore the binding interaction of plumbagin and BsFtsZ. The effects of plumbagin on the assembly and GTPase activity of the variant BsFtsZ proteins in vitro indicated that the residues D199 and V307 may be involved in the binding of plumbagin to BsFtsZ. The results suggest that plumbagin inhibits bacterial proliferation by inhibiting the assembly of FtsZ, and provide insight into the binding site of plumbagin on BsFtsZ, which may help in the design of potent FtsZ-targeted antibacterial agents. © 2013 FEBS.

Modeling FtsZ ring formation in the bacterial cell-anisotropic aggregation via mutual interactions of polymer rods.

PubMed

Fischer-Friedrich, Elisabeth; Gov, Nir

2011-04-01

The cytoskeletal protein FtsZ polymerizes to a ring structure (Z ring) at the inner cytoplasmic membrane that marks the future division site and scaffolds the division machinery in many bacterial species. FtsZ is known to polymerize in the presence of GTP into single-stranded protofilaments. In vivo, FtsZ polymers become associated with the cytoplasmic membrane via interaction with the membrane-binding proteins FtsA and ZipA. The FtsZ ring structure is highly dynamic and undergoes constantly polymerization and depolymerization processes and exchange with the cytoplasmic pool. In this theoretical study, we consider a scenario of Z ring self-organization via self-enhanced attachment of FtsZ polymers due to end-to-end interactions and lateral interactions of FtsZ polymers on the membrane. With the assumption of exclusively circumferential polymer orientations, we derive coarse-grained equations for the dynamics of the pool of cytoplasmic and membrane-bound FtsZ. To capture stochastic effects expected in the system due to low particle numbers, we simulate our computational model using a Gillespie-type algorithm. We obtain ring- and arc-shaped aggregations of FtsZ polymers on the membrane as a function of monomer numbers in the cell. In particular, our model predicts the number of FtsZ rings forming in the cell as a function of cell geometry and FtsZ concentration. We also calculate the time of FtsZ ring localization to the midplane in the presence of Min oscillations. Finally, we demonstrate that the assumptions and results of our model are confirmed by 3D reconstructions of fluorescently-labeled FtsZ structures in E. coli that we obtained.

FtsZ rings and helices: physical mechanisms for the dynamic alignment of biopolymers in rod-shaped bacteria.

PubMed

Fischer-Friedrich, Elisabeth; Friedrich, Benjamin M; Gov, Nir S

2012-02-01

In many bacterial species, the protein FtsZ forms a cytoskeletal ring that marks the future division site and scaffolds the division machinery. In rod-shaped bacteria, most frequently membrane-attached FtsZ rings or ring fragments are reported and occasionally helices. By contrast, axial FtsZ clusters have never been reported. In this paper, we investigate theoretically how dynamic FtsZ aggregates align in rod-shaped bacteria. We study systematically different physical mechanisms that affect the alignment of FtsZ polymers using a computational model that relies on autocatalytic aggregation of FtsZ filaments at the membrane. Our study identifies a general tool kit of physical and geometrical mechanisms by which rod-shaped cells align biopolymer aggregates. Our analysis compares the relative impact of each mechanism on the circumferential alignment of FtsZ as observed in rod-shaped bacteria. We determine spontaneous curvature of FtsZ polymers and axial confinement of FtsZ on the membrane as the strongest factors. Including Min oscillations in our model, we find that these stabilize axial and helical clusters on short time scales, but promote the formation of an FtsZ ring at the cell middle at longer times. This effect could provide an explanation to the long standing puzzle of transiently observed oscillating FtsZ helices in Escherichia coli cells prior to cell division.

Sensitivity Analysis for CO2 Retrieval using GOSAT-2 FTS-2 Simulator

NASA Astrophysics Data System (ADS)

Kamei, Akihide; Yoshida, Yukio; Dupuy, Eric; Yokota, Yasuhiro; Hiraki, Kaduo; Matsunaga, Tsuneo

2015-04-01

The Greenhouse Gases Observing Satellite (GOSAT), launched in 2009, is the world's first satellite dedicated to global greenhouse gases observation. GOSAT-2, the successor mission to GOSAT, is scheduled for launch in early 2018. The Fourier Transform Spectrometer-2 (FTS-2) is the primary sensor onboard GOSAT-2. It observes infrared light reflected and emitted from the Earth's surface and atmosphere. The FTS-2 obtains high resolution spectra using three bands in the near to short-wavelength infrared (SWIR) region and two bands in the thermal infrared (TIR) region. Column amounts and vertical profiles of carbon dioxide (CO2) and methane (CH4) are retrieved from the radiance spectra obtained with the SWIR and TIR bands, respectively. Further, compared to the FTS onboard the GOSAT, the FTS-2 has several improvements: 1) added spectral coverage in the SWIR region for carbon monoxide (CO) retrieval, 2) increased signal-to-noise ratio (SNR) for all bands, 3) extended range of along-track pointing angles for sunglint observations, 4) intelligent pointing to avoid cloud contamination. Since 2012, we have been developing a simulator software to simulate the spectral radiance data that will be acquired by the GOSAT-2 FTS-2. The purpose of the GOSAT-2 FTS-2 simulator is to analyze/optimize data with respect to the sensor specification, the parameters for Level 1 processing, and the improvement of the Level 2 algorithms. The GOSAT-2 FTS-2 simulator includes the six components: 1) overall control, 2) sensor carrying platform, 3) spectral radiance calculation, 4) Fourier Transform module, 5) Level 1B (L1B) processing, and 6) L1B data output. It has been installed on the GOSAT Research Computation Facility (GOSAT RCF), which is a high-performance and energy-efficient supercomputer. More realistic and faster simulations have been made possible by the improvement of the details of sensor characteristics, the sophistication of the data processing and algorithms, the addition of the

YeeV is an Escherichia coli toxin that inhibits cell division by targeting the cytoskeleton proteins, FtsZ and MreB.

PubMed

Tan, Qian; Awano, Naoki; Inouye, Masayori

2011-01-01

Toxin-antitoxin (TA) systems of free-living bacteria have recently demonstrated that these toxins inhibit cell growth by targeting essential functions of cellular metabolism. Here we show that YeeV toxin inhibits cell division, leads to a change in morphology and lysis of Escherichia coli cells. YeeV interacts with two essential cytoskeleton proteins, FtsZ and MreB. Purified YeeV inhibits both the GTPase activity and the GTP-dependent polymerization of FtsZ. YeeV also inhibits ATP-dependent polymerization of MreB. Truncated C-terminal deletions of YeeV result in elongation of cells, and a deletion of the first 15 amino acids from the N-terminus of YeeV caused lemon-shaped cell formation. The YeeV toxin is distinct from other well-studied toxins: it directs the binding of two cytoskeletal proteins and inhibits FtsZ and MreB simultaneously. © 2010 Blackwell Publishing Ltd.

Novel Trisubstituted Benzimidazoles, Targeting Mtb FtsZ, As A New Class of Antitubercular Agents

PubMed Central

Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Zanardi, Ilaria; Ruzsicska, Bela; Knudson, Susan; Tonge, Peter J.; Slayden, Richard A.; Ojima, Iwao

2010-01-01

Libraries of novel trisubstituted benzimidazoles were created through rational drug design. A good number of these benzimidazoles exhibited promising MIC values in the range of 0.5-6 μg/mL (2-15 μM) for their antibacterial activity against Mtb H37Rv strain. Moreover, five of the lead compounds also exhibited excellent activity against clinical Mtb strains with different drug-resistance profiles. All lead compounds do not show appreciable cytotoxicity (IC50 >200 μM) against Vero cells, which inhibit Mtb FtsZ assembly in a dose dependent manner. The two lead compounds unexpectedly showed enhancement of the GTPase activity of Mtb FtsZ. The result strongly suggests that the increased GTPase activity destabilizes FtsZ assembly leading to efficient inhibition of FtsZ polymerization and filament formation. The TEM and SEM analyses of Mtb FtsZ and Mtb cells, respectively, treated with a lead compound strongly suggest that lead benzimidazoles have a novel mechanism of action on the inhibition of Mtb FtsZ assembly and Z-ring formation. PMID:21126020

Novel trisubstituted benzimidazoles, targeting Mtb FtsZ, as a new class of antitubercular agents.

PubMed

Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Zanardi, Ilaria; Ruzsicska, Bela; Knudson, Susan; Tonge, Peter J; Slayden, Richard A; Ojima, Iwao

2011-01-13

Libraries of novel trisubstituted benzimidazoles were created through rational drug design. A good number of these benzimidazoles exhibited promising MIC values in the range of 0.5-6 μg/mL (2-15 μM) for their antibacterial activity against Mtb H37Rv strain. Moreover, five of the lead compounds also exhibited excellent activity against clinical Mtb strains with different drug-resistance profiles. All lead compounds did not show appreciable cytotoxicity (IC(50) > 200 μM) against Vero cells, which inhibited Mtb FtsZ assembly in a dose dependent manner. The two lead compounds unexpectedly showed enhancement of the GTPase activity of Mtb FtsZ. The result strongly suggests that the increased GTPase activity destabilizes FtsZ assembly, leading to efficient inhibition of FtsZ polymerization and filament formation. The TEM and SEM analyses of Mtb FtsZ and Mtb cells, respectively, treated with a lead compound strongly suggest that lead benzimidazoles have a novel mechanism of action on the inhibition of Mtb FtsZ assembly and Z-ring formation.

The optical design of a far infrared imaging FTS for SPICA

NASA Astrophysics Data System (ADS)

Pastor, Carmen; Zuluaga, Pablo; Jellema, Willem; González Fernández, Luis Miguel; Belenguer, Tomas; Torres Redondo, Josefina; Kooijman, Peter Paul; Najarro, Francisco; Eggens, Martin; Roelfsema, Peter; Nakagawa, Takao

2014-08-01

This paper describes the optical design of the far infrared imaging spectrometer for the JAXA's SPICA mission. The SAFARI instrument, is a cryogenic imaging Fourier transform spectrometer (iFTS), designed to perform backgroundlimited spectroscopic and photometric imaging in the band 34-210 μm. The all-reflective optical system is highly modular and consists of three main modules; input optics module, interferometer module (FTS) and camera bay optics. A special study has been dedicated to the spectroscopic performance of the instrument, in which the spectral response and interference of the instrument have been modeled, as the FTS mechanism scans over the total desired OPD range.

A large-stroke cryogenic imaging FTS system for SPICA-Safari

NASA Astrophysics Data System (ADS)

Jellema, Willem; van Loon, Dennis; Naylor, David; Roelfsema, Peter

2014-08-01

The scientific goals of the far-infrared astronomy mission SPICA challenge the design of a large-stroke imaging FTS for Safari, inviting for the development of a new generation of cryogenic actuators with very low dissipation. In this paper we present the Fourier Transform Spectrometer (FTS) system concept, as foreseen for SPICA-Safari, and we discuss the technical developments required to satisfy the instrument performance.

Development of the GOSAT-2 FTS-2 Simulator and Preliminary Sensitivity Analysis for CO2 Retrieval

NASA Astrophysics Data System (ADS)

Kamei, A.; Yoshida, Y.; Dupuy, E.; Hiraki, K.; Yokota, Y.; Oishi, Y.; Murakami, K.; Morino, I.; Matsunaga, T.

2013-12-01

The Greenhouse Gases Observing Satellite-2 (GOSAT-2), which is a successor mission to the GOSAT, is planned to be launched in FY 2017. The Fourier Transform Spectrometer-2 (FTS-2) onboard the GOSAT-2 is a primary sensor to observe infrared light reflected and emitted from the Earth's surface and atmosphere. The FTS-2 obtains high-spectral resolution spectra with four bands from near to short-wavelength infrared (SWIR) region and one band in the thermal infrared (TIR) region. The column amounts of carbon dioxide (CO2) and methane (CH4) are retrieved from the obtained radiance spectra with SWIR bands. Compared to the FTS onboard the GOSAT, the FTS-2 includes an additional SWIR band to allow for carbon monoxide (CO) measurement. We have been developing a tool, named GOSAT-2 FTS-2 simulator, which is capable of simulating the spectral radiance data observed by the FTS-2 using the Pstar2 radiative transfer code. The purpose of the GOSAT-2 FTS-2 simulator is to obtain data which is exploited in the sensor specification, the optimization of parameters for Level 1 processing, and the improvement of Level 2 algorithms. The GOSAT-2 FTS-2 simulator, composed of the six components: 1) Overall control, 2) Onboarding platform, 3) Spectral radiance calculation, 4) Fourier transform, 5) L1B processing, and 6) L1B data output, has been installed on the GOSAT Research Computation Facility (GOSAT RCF), which is a large-scale, high-performance, and energy-efficient computer. We present the progress in the development of the GOSAT-2 FTS-2 simulator and the preliminary sensitivity analysis, relating to the engineering parameters, the aerosols and clouds, and so on, on the Level 1 processing for CO2 retrieval from the obtained data by simulating the FTS-2 SWIR observation using the GOSAT-2 FTS-2 simulator.

An analysis of FtsZ assembly using small angle X-ray scattering and electron microscopy.

PubMed

Kuchibhatla, Anuradha; Abdul Rasheed, A S; Narayanan, Janaky; Bellare, Jayesh; Panda, Dulal

2009-04-09

Small angle X-ray scattering (SAXS) was used for the first time to study the self-assembly of the bacterial cell division protein, FtsZ, with three different additives: calcium chloride, monosodium glutamate and DEAE-dextran hydrochloride in solution. The SAXS data were analyzed assuming a model form factor and also by a model-independent analysis using the pair distance distribution function. Transmission electron microscopy (TEM) was used for direct observation of the FtsZ filaments. By sectioning and negative staining with glow discharged grids, very high bundling as well as low bundling polymers were observed under different assembly conditions. FtsZ polymers formed different structures in the presence of different additives and these additives were found to increase the bundling of FtsZ protofilaments by different mechanisms. The combined use of SAXS and TEM provided us a significant insight of the assembly of FtsZ and microstructures of the assembled FtsZ polymers.

Targeting cell division: Small-molecule inhibitors of FtsZ GTPase perturb cytokinetic ring assembly and induce bacterial lethality

PubMed Central

Margalit, Danielle N.; Romberg, Laura; Mets, Rebecca B.; Hebert, Alan M.; Mitchison, Timothy J.; Kirschner, Marc W.; RayChaudhuri, Debabrata

2004-01-01

FtsZ, the ancestral homolog of eukaryotic tubulins, is a GTPase that assembles into a cytokinetic ring structure essential for cell division in prokaryotic cells. Similar to tubulin, purified FtsZ polymerizes into dynamic protofilaments in the presence of GTP; polymer assembly is accompanied by GTP hydrolysis. We used a high-throughput protein-based chemical screen to identify small molecules that target assembly-dependent GTPase activity of FtsZ. Here, we report the identification of five structurally diverse compounds, named Zantrins, which inhibit FtsZ GTPase either by destabilizing the FtsZ protofilaments or by inducing filament hyperstability through increased lateral association. These two classes of FtsZ inhibitors are reminiscent of the antitubulin drugs colchicine and Taxol, respectively. We also show that Zantrins perturb FtsZ ring assembly in Escherichia coli cells and cause lethality to a variety of bacteria in broth cultures, indicating that FtsZ antagonists may serve as chemical leads for the development of new broad-spectrum antibacterial agents. Our results illustrate the utility of small-molecule chemical probes to study FtsZ polymerization dynamics and the feasibility of FtsZ as a novel therapeutic target. PMID:15289600

FtsZ Cytoskeletal Filaments as a Template for Metallic Nanowire Fabrication.

PubMed

Ostrov, Nili; Fichman, Galit; Adler-Abramovich, Lihi; Gazit, Ehud

2015-01-01

Supramolecular protein assemblies can serve as templates for the fabrication of inorganic nanowires due to their morphological reproducibility and innate proclivity to form well-ordered structures. Amongst the variety of naturally occurring nano-scale assemblies, cytoskeletal fibers from diverse biological sources represent a unique family of scaffolds for biomimetics as they efficiently self-assemble in vitro in a controllable manner to form stable filaments. Here, we harness the bacterial FtsZ filament system as a scaffold for protein-based metal nanowires, and further demonstrate the control of wire alignment with the use of an external magnetic field. Due to the ease at which the bacterial FtsZ is overexpressed and purified, as well as the extensive studies of its ultrastructural properties and physiological significance, FtsZ filaments are an ideal substrate for large-scale production and chemical manipulation. Using a biologically compatible electroless metal deposition technique initiated by adsorption of platinum as a surface catalyst, we demonstrate the coating of assembled FtsZ filaments with iron, nickel, gold, and copper to fabricate continuous nanowires with diameters ranging from 10-50 nm. Organic-inorganic hybrid wires were analyzed using high-resolution field-emission-gun transmission and scanning electron microscopy, and confirmed by energy-dispersive elemental analysis. We also achieved alignment of ferrofluid-coated FtsZ filaments using an external magnetic field. Overall, we provide evidence for the robustness of the FtsZ filament system as a molecular scaffold, and offer an efficient, biocompatible procedure for facile bottom-up assembly of metallic wires on biological templates. We believe that bottom-up fabrication methods as reported herein significantly contribute to the expanding toolkit available for the incorporation of biological materials in nano-scale devices for electronic and electromechanical applications.

Influence of GTP/GDP and magnesium ion on the solvated structure of the protein FtsZ: a molecular dynamics study.

PubMed

Jamous, Carla; Basdevant, Nathalie; Ha-Duong, Tap

2014-01-01

We present here a structural analysis of ten extensive all-atom molecular dynamics simulations of the monomeric protein FtsZ in various binding states. Since the polymerization and GTPase activities of FtsZ depend on the nature of a bound nucleotide as well as on the presence of a magnesium ion, we studied the structural differences between the average conformations of the following five systems: FtsZ-Apo, FtsZ-GTP, FtsZ-GDP, FtsZ-GTP-Mg, and FtsZ-GDP-Mg. The in silico solvated average structure of FtsZ-Apo significantly differs from the crystallographic structure 1W59 of FtsZ which was crystallized in a dimeric form without nucleotide and magnesium. The simulated Apo form of the protein also clearly differs from the FtsZ structures when it is bound to its ligand, the most important discrepancies being located in the loops surrounding the nucleotide binding pocket. The three average structures of FtsZ-GTP, FtsZ-GDP, and FtsZ-GTP-Mg are overall similar, except for the loop T7 located at the opposite side of the binding pocket and whose conformation in FtsZ-GDP notably differs from the one in FtsZ-GTP and FtsZ-GTP-Mg. The presence of a magnesium ion in the binding pocket has no impact on the FtsZ conformation when it is bound to GTP. In contrast, when the protein is bound to GDP, the divalent cation causes a translation of the nucleotide outwards the pocket, inducing a significant conformational change of the loop H6-H7 and the top of helix H7.

Cloning and characterization of ftsZ and pyrF from the archaeon Thermoplasma acidophilum

NASA Technical Reports Server (NTRS)

Yaoi, T.; Laksanalamai, P.; Jiemjit, A.; Kagawa, H. K.; Alton, T.; Trent, J. D.

2000-01-01

To characterize cytoskeletal components of archaea, the ftsZ gene from Thermoplasma acidophilum was cloned and sequenced. In T. acidophilum ftsZ, which is involved in cell division, was found to be in an operon with the pyrF gene, which encodes orotidine-5'-monophosphate decarboxylase (ODC), an essential enzyme in pyrimidine biosynthesis. Both ftsZ and pyrF from T. acidophilum were expressed in Escherichia coli and formed functional proteins. FtsZ expression in wild-type E. coli resulted in the filamentous phenotype characteristic of ftsZ mutants. T. acidophilum pyrF expression in an E. coli mutant lacking pyrF complemented the mutation and rescued the strain. Sequence alignments of ODCs from archaea, bacteria, and eukarya reveal five conserved regions, two of which have homology to 3-hexulose-6-phosphate synthase (HPS), suggesting a common substrate recognition and binding motif. Copyright 2000 Academic Press.

Retrieval of carbon dioxide vertical profiles from solar occultation observations and associated error budgets for ACE-FTS and CASS-FTS

NASA Astrophysics Data System (ADS)

Sioris, C. E.; Boone, C. D.; Nassar, R.; Sutton, K. J.; Gordon, I. E.; Walker, K. A.; Bernath, P. F.

2014-02-01

An algorithm is developed to retrieve the vertical profile of carbon dioxide in the 5 to 25 km altitude range using mid-infrared solar occultation spectra from the main instrument of the ACE (Atmospheric Chemistry Experiment) mission, namely the Fourier Transform Spectrometer (FTS). The main challenge is to find an atmospheric phenomenon which can be used for accurate tangent height determination in the lower atmosphere, where the tangent heights (THs) calculated from geometric and timing information is not of sufficient accuracy. Error budgets for the retrieval of CO2 from ACE-FTS and the FTS on a potential follow-on mission named CASS (Chemical and Aerosol Sounding Satellite) are calculated and contrasted. Retrieved THs are typically within 60 m of those retrieved using the ACE version 3.x software after revisiting the temperature dependence of the N2 CIA (Collision-Induced Absorption) laboratory measurements and accounting for sulfate aerosol extinction. After correcting for the known residual high bias of ACE version 3.x THs expected from CO2 spectroscopic/isotopic inconsistencies, the remaining bias for tangent heights determined with the N2 CIA is -20m. CO2 in the 5-13 km range in the 2009-2011 time frame is validated against aircraft measurements from CARIBIC, CONTRAIL and HIPPO, yielding typical biases of -1.7 ppm in the 5-13 km range. The standard error of these biases in this vertical range is 0.4 ppm. The multi-year ACE-FTS dataset is valuable in determining the seasonal variation of the latitudinal gradient which arises from the strong seasonal cycle in the Northern Hemisphere troposphere. The annual growth of CO2 in this time frame is determined to be 2.5 ± 0.7 ppm yr-1, in agreement with the currently accepted global growth rate based on ground-based measurements.

Architecture of the ring formed by the tubulin homologue FtsZ in bacterial cell division

PubMed Central

Szwedziak, Piotr; Wang, Qing; Bharat, Tanmay A M; Tsim, Matthew; Löwe, Jan

2014-01-01

Membrane constriction is a prerequisite for cell division. The most common membrane constriction system in prokaryotes is based on the tubulin homologue FtsZ, whose filaments in E. coli are anchored to the membrane by FtsA and enable the formation of the Z-ring and divisome. The precise architecture of the FtsZ ring has remained enigmatic. In this study, we report three-dimensional arrangements of FtsZ and FtsA filaments in C. crescentus and E. coli cells and inside constricting liposomes by means of electron cryomicroscopy and cryotomography. In vivo and in vitro, the Z-ring is composed of a small, single-layered band of filaments parallel to the membrane, creating a continuous ring through lateral filament contacts. Visualisation of the in vitro reconstituted constrictions as well as a complete tracing of the helical paths of the filaments with a molecular model favour a mechanism of FtsZ-based membrane constriction that is likely to be accompanied by filament sliding. DOI: http://dx.doi.org/10.7554/eLife.04601.001 PMID:25490152

Screening and Development of New Inhibitors of FtsZ from M. Tuberculosis

PubMed Central

Mathew, Bini; Ross, Larry; Connelly, Michele C.; Lofton, Hava; Rajagopalan, Malini; Guy, R. Kiplin; Reynolds, Robert C.

2016-01-01

A variety of commercial analogs and a newer series of Sulindac derivatives were screened for inhibition of M. tuberculosis (Mtb) in vitro and specifically as inhibitors of the essential mycobacterial tubulin homolog, FtsZ. Due to the ease of preparing diverse analogs and a favorable in vivo pharmacokinetic and toxicity profile of a representative analog, the Sulindac scaffold may be useful for further development against Mtb with respect to in vitro bacterial growth inhibition and selective activity for Mtb FtsZ versus mammalian tubulin. Further discovery efforts will require separating reported mammalian cell activity from both antibacterial activity and inhibition of Mtb FtsZ. Modeling studies suggest that these analogs bind in a specific region of the Mtb FtsZ polymer that differs from human tubulin and, in combination with a pharmacophore model presented herein, future hybrid analogs of the reported active molecules that more efficiently bind in this pocket may improve antibacterial activity while improving other drug characteristics. PMID:27768711

The Chloroplast Division Protein ARC6 Acts to Inhibit Disassembly of GDP-bound FtsZ2.

PubMed

Sung, Min Woo; Shaik, Rahamthulla; TerBush, Allan D; Osteryoung, Katherine W; Vitha, Stanislav; Holzenburg, Andreas

2018-05-16

Chloroplasts host photosynthesis and fulfill other metabolic functions that are essential to plant life. They have to divide by binary fission to maintain their numbers throughout cycles of cell division. Chloroplast division is achieved by a complex ring-shaped division machinery located on both the inner (stromal) and the outer (cytosolic) side of the chloroplast envelope. The inner division ring (termed the Z ring) is formed by the assembly of tubulin-like FtsZ1 and FtsZ2 proteins. ARC6 is a key chloroplast division protein that interacts with the Z ring. ARC6 spans the inner envelope membrane, is known to stabilize or maintain the Z ring, and anchors the Z ring to the inner membrane through interaction with FtsZ2. The underlying mechanism of Z-ring stabilization is not well understood. Here, biochemical and structural characterization of ARC6 was conducted using light scattering, sedimentation, and light and transmission electron microscopy. The recombinant protein was purified as a dimer. The results indicated that a truncated form of ARC6 (tARC6), representing the stromal portion of ARC6, affects FtsZ2 assembly without forming higher-order structures, and exerts its effect via FtsZ2 dynamics. tARC6 prevented GDP-induced FtsZ2 disassembly and caused a significant net increase in FtsZ2 assembly when GDP was present. Single particle analysis and 3D reconstruction were performed to elucidate the structural basis of ARC6 activity. Together, the data reveal that a dimeric form of tARC6 binds to FtsZ2 filaments and does not increase FtsZ polymerization rates but rather inhibits GDP-associated FtsZ2 disassembly. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.

Mapping flexibility and the assembly switch of cell division protein FtsZ by computational and mutational approaches.

PubMed

Martín-Galiano, Antonio J; Buey, Rubén M; Cabezas, Marta; Andreu, José M

2010-07-16

The molecular switch for nucleotide-regulated assembly and disassembly of the main prokaryotic cell division protein FtsZ is unknown despite the numerous crystal structures that are available. We have characterized the functional motions in FtsZ with a computational consensus of essential dynamics, structural comparisons, sequence conservation, and networks of co-evolving residues. Employing this information, we have constructed 17 mutants, which alter the FtsZ functional cycle at different stages, to modify FtsZ flexibility. The mutant phenotypes ranged from benign to total inactivation and included increased GTPase, reduced assembly, and stabilized assembly. Six mutations clustering at the long cleft between the C-terminal beta-sheet and core helix H7 deviated FtsZ assembly into curved filaments with inhibited GTPase, which still polymerize cooperatively. These mutations may perturb the predicted closure of the C-terminal domain onto H7 required for switching between curved and straight association modes and for GTPase activation. By mapping the FtsZ assembly switch, this work also gives insight into FtsZ druggability because the curved mutations delineate the putative binding site of the promising antibacterial FtsZ inhibitor PC190723.

Localization of FtsZ in Helicobacter pylori and Consequences for Cell Division

PubMed Central

Specht, Mara; Dempwolff, Felix; Schätzle, Sarah; Thomann, Ralf

2013-01-01

Of the various kinds of cell division, the most common mode is binary fission, the division of a cell into two morphologically identical daughter cells. However, in the case of asymmetric cell division, Caulobacter crescentus produces two morphologically and functionally distinct cell types. Here, we have studied cell cycle progression of the human pathogen Helicobacter pylori using a functional green fluorescent protein (GFP) fusion of FtsZ protein and membrane staining. In small cells, representing newly divided cells, FtsZ localizes to a single cell pole. During the cell cycle, spiral intermediates are formed until an FtsZ ring is positioned with very little precision, such that central as well as acentral rings can be observed. Daughter cells showed considerably different sizes, suggesting that H. pylori divides asymmetrically. Fluorescence recovery after photobleaching (FRAP) analyses demonstrate that the H. pylori FtsZ ring is about as dynamic as that of Escherichia coli but that polar assemblies show less turnover. Strikingly, our results demonstrate that H. pylori cell division follows a different route from that in E. coli and Bacillus subtilis. It is also different from that in C. crescentus, where cytokinesis regulation proteins like MipZ play a role. Therefore, this report provides the first cell-biological analysis of FtsZ dynamics in the human pathogen H. pylori and even in epsilonproteobacteria to our knowledge. In addition, analysis of the filament architecture of H. pylori and E. coli FtsZ filaments in the heterologous system of Drosophila melanogaster S2 Schneider cells revealed that both have different filamentation properties in vivo, suggesting a unique intrinsic characteristic of each protein. PMID:23335414

The hypermorph FtsA* protein has an in vivo role in relieving the Escherichia coli proto-ring block caused by excess ZapC+

PubMed Central

Ortiz, Cristina; Casanova, Mercedes; Palacios, Pilar

2017-01-01

Assembly of the proto-ring, formed by the essential FtsZ, FtsA and ZipA proteins, and its progression into a divisome, are essential events for Escherichia coli division. ZapC is a cytoplasmic protein that belongs to a group of non-essential components that assist FtsZ during proto-ring assembly. Any overproduction of these proteins leads to faulty FtsZ-rings, resulting in a cell division block. We show that ZapC overproduction can be counteracted by an excess of the ZipA-independent hypermorph FtsA* mutant, but not by similar amounts of wild type FtsA+. An excess of FtsA+ allowed regular spacing of the ZapC-blocked FtsZ-rings, but failed to promote recruitment of the late-assembling proteins FtsQ, FtsK and FtsN and therefore, to activate constriction. In contrast, overproduction of FtsA*, besides allowing correct FtsZ-ring localization at midcell, restored the ability of FtsQ, FtsK and FtsN to be incorporated into active divisomes. PMID:28877250

Two dynamin-like proteins stabilize FtsZ rings during Streptomyces sporulation.

PubMed

Schlimpert, Susan; Wasserstrom, Sebastian; Chandra, Govind; Bibb, Maureen J; Findlay, Kim C; Flärdh, Klas; Buttner, Mark J

2017-07-25

During sporulation, the filamentous bacteria Streptomyces undergo a massive cell division event in which the synthesis of ladders of sporulation septa convert multigenomic hyphae into chains of unigenomic spores. This process requires cytokinetic Z-rings formed by the bacterial tubulin homolog FtsZ, and the stabilization of the newly formed Z-rings is crucial for completion of septum synthesis. Here we show that two dynamin-like proteins, DynA and DynB, play critical roles in this process. Dynamins are a family of large, multidomain GTPases involved in key cellular processes in eukaryotes, including vesicle trafficking and organelle division. Many bacterial genomes encode dynamin-like proteins, but the biological function of these proteins has remained largely enigmatic. Using a cell biological approach, we show that the two Streptomyces dynamins specifically localize to sporulation septa in an FtsZ-dependent manner. Moreover, dynamin mutants have a cell division defect due to the decreased stability of sporulation-specific Z-rings, as demonstrated by kymographs derived from time-lapse images of FtsZ ladder formation. This defect causes the premature disassembly of individual Z-rings, leading to the frequent abortion of septum synthesis, which in turn results in the production of long spore-like compartments with multiple chromosomes. Two-hybrid analysis revealed that the dynamins are part of the cell division machinery and that they mediate their effects on Z-ring stability during developmentally controlled cell division via a network of protein-protein interactions involving DynA, DynB, FtsZ, SepF, SepF2, and the FtsZ-positioning protein SsgB.

The Flight Telerobotic Servicer (FTS) - A focus for automation and robotics on the Space Station

NASA Technical Reports Server (NTRS)

Hinkal, Sanford W.; Andary, James F.; Watzin, James G.; Provost, David E.

1987-01-01

The concept, fundamental design principles, and capabilities of the FTS, a multipurpose telerobotic system for use on the Space Station and Space Shuttle, are discussed. The FTS is intended to assist the crew in the performance of extravehicular tasks; the telerobot will also be used on the Orbital Maneuvering Vehicle to service free-flyer spacecraft. The FTS will be capable of both teleoperation and autonomous operation; eventually it may also utilize ground control. By careful selection of the functional architecture and a modular approach to the hardware and software design, the FTS can accept developments in artificial intelligence and newer, more advanced sensors, such as machine vision and collision avoidance.

Mapping Flexibility and the Assembly Switch of Cell Division Protein FtsZ by Computational and Mutational Approaches*♦

PubMed Central

Martín-Galiano, Antonio J.; Buey, Rubén M.; Cabezas, Marta; Andreu, José M.

2010-01-01

The molecular switch for nucleotide-regulated assembly and disassembly of the main prokaryotic cell division protein FtsZ is unknown despite the numerous crystal structures that are available. We have characterized the functional motions in FtsZ with a computational consensus of essential dynamics, structural comparisons, sequence conservation, and networks of co-evolving residues. Employing this information, we have constructed 17 mutants, which alter the FtsZ functional cycle at different stages, to modify FtsZ flexibility. The mutant phenotypes ranged from benign to total inactivation and included increased GTPase, reduced assembly, and stabilized assembly. Six mutations clustering at the long cleft between the C-terminal β-sheet and core helix H7 deviated FtsZ assembly into curved filaments with inhibited GTPase, which still polymerize cooperatively. These mutations may perturb the predicted closure of the C-terminal domain onto H7 required for switching between curved and straight association modes and for GTPase activation. By mapping the FtsZ assembly switch, this work also gives insight into FtsZ druggability because the curved mutations delineate the putative binding site of the promising antibacterial FtsZ inhibitor PC190723. PMID:20472561

An archaebacterial homologue of the essential eubacterial cell division protein FtsZ.

PubMed Central

Baumann, P; Jackson, S P

1996-01-01

Life falls into three fundamental domains--Archaea, Bacteria, and Eucarya (formerly archaebacteria, eubacteria, and eukaryotes,. respectively). Though Archaea lack nuclei and share many morphological features with Bacteria, molecular analyses, principally of the transcription and translation machineries, have suggested that Archaea are more related to Eucarya than to Bacteria. Currently, little is known about the archaeal cell division apparatus. In Bacteria, a crucial component of the cell division machinery is FtsZ, a GTPase that localizes to a ring at the site of septation. Interestingly, FtsZ is distantly related in sequence to eukaryotic tubulins, which also interact with GTP and are components of the eukaryotic cell cytoskeleton. By screening for the ability to bind radiolabeled nucleotides, we have identified a protein of the hyperthermophilic archaeon Pyrococcus woesei that interacts tightly and specifically with GTP. Furthermore, through screening an expression library of P. woesei genomic DNA, we have cloned the gene encoding this protein. Sequence comparisons reveal that the P. woesei GTP-binding protein is strikingly related in sequence to eubacterial FtsZ and is marginally more similar to eukaryotic tubulins than are bacterial FtsZ proteins. Phylogenetic analyses reinforce the notion that there is an evolutionary linkage between FtsZ and tubulins. These findings suggest that the archaeal cell division apparatus may be fundamentally similar to that of Bacteria and lead us to consider the evolutionary relationships between Archaea, Bacteria, and Eucarya. Images Fig. 1 Fig. 2 PMID:8692886

An archaebacterial homologue of the essential eubacterial cell division protein FtsZ.

PubMed

Baumann, P; Jackson, S P

1996-06-25

Life falls into three fundamental domains--Archaea, Bacteria, and Eucarya (formerly archaebacteria, eubacteria, and eukaryotes,. respectively). Though Archaea lack nuclei and share many morphological features with Bacteria, molecular analyses, principally of the transcription and translation machineries, have suggested that Archaea are more related to Eucarya than to Bacteria. Currently, little is known about the archaeal cell division apparatus. In Bacteria, a crucial component of the cell division machinery is FtsZ, a GTPase that localizes to a ring at the site of septation. Interestingly, FtsZ is distantly related in sequence to eukaryotic tubulins, which also interact with GTP and are components of the eukaryotic cell cytoskeleton. By screening for the ability to bind radiolabeled nucleotides, we have identified a protein of the hyperthermophilic archaeon Pyrococcus woesei that interacts tightly and specifically with GTP. Furthermore, through screening an expression library of P. woesei genomic DNA, we have cloned the gene encoding this protein. Sequence comparisons reveal that the P. woesei GTP-binding protein is strikingly related in sequence to eubacterial FtsZ and is marginally more similar to eukaryotic tubulins than are bacterial FtsZ proteins. Phylogenetic analyses reinforce the notion that there is an evolutionary linkage between FtsZ and tubulins. These findings suggest that the archaeal cell division apparatus may be fundamentally similar to that of Bacteria and lead us to consider the evolutionary relationships between Archaea, Bacteria, and Eucarya.

Retrieval of carbon dioxide vertical profiles from solar occultation observations and associated error budgets for ACE-FTS and CASS-FTS

NASA Astrophysics Data System (ADS)

Sioris, C. E.; Boone, C. D.; Nassar, R.; Sutton, K. J.; Gordon, I. E.; Walker, K. A.; Bernath, P. F.

2014-07-01

An algorithm is developed to retrieve the vertical profile of carbon dioxide in the 5 to 25 km altitude range using mid-infrared solar occultation spectra from the main instrument of the ACE (Atmospheric Chemistry Experiment) mission, namely the Fourier transform spectrometer (FTS). The main challenge is to find an atmospheric phenomenon which can be used for accurate tangent height determination in the lower atmosphere, where the tangent heights (THs) calculated from geometric and timing information are not of sufficient accuracy. Error budgets for the retrieval of CO2 from ACE-FTS and the FTS on a potential follow-on mission named CASS (Chemical and Aerosol Sounding Satellite) are calculated and contrasted. Retrieved THs have typical biases of 60 m relative to those retrieved using the ACE version 3.x software after revisiting the temperature dependence of the N2 CIA (collision-induced absorption) laboratory measurements and accounting for sulfate aerosol extinction. After correcting for the known residual high bias of ACE version 3.x THs expected from CO2 spectroscopic/isotopic inconsistencies, the remaining bias for tangent heights determined with the N2 CIA is -20 m. CO2 in the 5-13 km range in the 2009-2011 time frame is validated against aircraft measurements from CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container), CONTRAIL (Comprehensive Observation Network for Trace gases by Airline), and HIPPO (HIAPER Pole-to-Pole Observations), yielding typical biases of -1.7 ppm in the 5-13 km range. The standard error of these biases in this vertical range is 0.4 ppm. The multi-year ACE-FTS data set is valuable in determining the seasonal variation of the latitudinal gradient which arises from the strong seasonal cycle in the Northern Hemisphere troposphere. The annual growth of CO2 in this time frame is determined to be 2.6 ± 0.4 ppm year-1, in agreement with the currently accepted global growth rate based on

Discovery of chlamydial peptidoglycan reveals bacteria with murein sacculi but without FtsZ

NASA Astrophysics Data System (ADS)

Pilhofer, Martin; Aistleitner, Karin; Biboy, Jacob; Gray, Joe; Kuru, Erkin; Hall, Edward; Brun, Yves V.; Vannieuwenhze, Michael S.; Vollmer, Waldemar; Horn, Matthias; Jensen, Grant J.

2013-12-01

Chlamydiae are important pathogens and symbionts with unique cell biological features. They lack the cell-division protein FtsZ, and the existence of peptidoglycan (PG) in their cell wall has been highly controversial. FtsZ and PG together function in orchestrating cell division and maintaining cell shape in almost all other bacteria. Using electron cryotomography, mass spectrometry and fluorescent labelling dyes, here we show that some environmental chlamydiae have cell wall sacculi consisting of a novel PG type. Treatment with fosfomycin (a PG synthesis inhibitor) leads to lower infection rates and aberrant cell shapes, suggesting that PG synthesis is crucial for the chlamydial life cycle. Our findings demonstrate for the first time the presence of PG in a member of the Chlamydiae. They also present a unique example of a bacterium with a PG sacculus but without FtsZ, challenging the current hypothesis that it is the absence of a cell wall that renders FtsZ non-essential.

Thymic hormone containing cells. III. Evidence for a feed-back regulation of the secretion of the serum thymic factor (FTS) by thymic epithelial cells.

PubMed Central

Savino, W; Dardenne, M; Bach, J F

1983-01-01

Cells containing the serum thymic factor (FTS), as measured by indirect immunofluorescence, were studied in mice either FTS depleted by injection of anti-FTS monoclonal antibodies or immunization against FTS coupled to bovine serum albumin (FTS-BSA), or FTS enriched by multiple injections of synthetic thymulin (FTS-Zn). Injections of thymulin did not significantly depress FTS secretion. Conversely, long term elimination of FTS from peripheral blood caused a great increase in the thymic intracellular content of FTS, as evidenced by the higher number of FTS containing cells observed with immunofluorescence. These data could provide the first evidence of a feed-back control of thymic endocrine function. PMID:6683135

FTS is responsible for radiation-induced nuclear phosphorylation of EGFR and repair of DNA damage in cervical cancer cells.

PubMed

Muthusami, Sridhar; Prabakaran, D S; Yu, Jae-Ran; Park, Woo-Yoon

2015-02-01

Radiation-induced nuclear stabilization and phosphorylation of epidermal growth factor receptor (EGFR) confers radioresistance. Understanding of the factor(s) regulating the nuclear stabilization and phosphorylation of EGFR is important for the modulation of radioresistance. Present study was designed to delineate the regulation of EGFR nuclear stabilization and phosphorylation by fused toes homolog (FTS), an oncoprotein, which is responsible for the radioresistance in cervical cancer cells. A cervical cancer cell line, ME180 was used. Radiation-induced change in the levels of EGFR, p-EGFR and FTS were evaluated in the cytoplasm and nucleus using Western blot analyses. FTS was silenced using siRNA-based approach. Interaction between EGFR and FTS was assessed using immunofluorescence and immunoprecipitation analyses. Double-strand breaks (DSB) of DNA were assessed using γ H2AX. Radiation increased the levels of EGFR and FTS in the cytoplasm and nucleus. EGFR and FTS are in physical association with each other and are co-localized in the cells. FTS silencing largely reduced the nuclear stabilization and phosphorylation of EGFR and DNA-protein kinase along with increased initial and residual DSBs. EGFR and FTS physically associate with each other and FTS silencing radiosensitizes ME180 cells through impaired nuclear EGFR signaling.

Comparison of upper tropospheric carbon monoxide from MOPITT, ACE-FTS, and HIPPO-QCLS

NASA Astrophysics Data System (ADS)

Martínez-Alonso, Sara; Deeter, Merritt N.; Worden, Helen M.; Gille, John C.; Emmons, Louisa K.; Pan, Laura L.; Park, Mijeong; Manney, Gloria L.; Bernath, Peter F.; Boone, Chris D.; Walker, Kaley A.; Kolonjari, Felicia; Wofsy, Steven C.; Pittman, Jasna; Daube, Bruce C.

2014-12-01

Products from the Measurements Of Pollution In The Troposphere (MOPITT) instrument are regularly validated using in situ airborne measurements. However, few of these measurements reach into the upper troposphere, thus hindering MOPITT validation in that region. Here we evaluate upper tropospheric (~500 hPa to the tropopause) MOPITT CO profiles by comparing them to satellite Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) retrievals and to measurements from the High-performance Instrumented Airborne Platform for Environmental Research Pole to Pole Observations (HIPPO) Quantum Cascade Laser Spectrometer (QCLS). Direct comparison of colocated v5 MOPITT thermal infrared-only retrievals, v3.0 ACE-FTS retrievals, and HIPPO-QCLS measurements shows a slight positive MOPITT CO bias within its 10% accuracy requirement with respect to the other two data sets. Direct comparison of colocated ACE-FTS and HIPPO-QCLS measurements results in a small number of samples due to the large disparity in sampling pattern and density of these data sets. Thus, two additional indirect techniques for comparison of noncoincident data sets have been applied: tracer-tracer (CO-O3) correlation analysis and analysis of profiles in tropopause coordinates. These techniques suggest a negative bias of ACE-FTS with respect to HIPPO-QCLS; this could be caused by differences in resolution (horizontal, vertical) or by deficiencies in the ACE-FTS CO retrievals below ~20 km of altitude, among others. We also investigate the temporal stability of MOPITT and ACE-FTS data, which provide unique global CO records and are thus important in climate analysis. Our results indicate that the relative bias between the two data sets has remained generally stable during the 2004-2010 period.

CbtA toxin of Escherichia coli inhibits cell division and cell elongation via direct and independent interactions with FtsZ and MreB.

PubMed

Heller, Danielle M; Tavag, Mrinalini; Hochschild, Ann

2017-09-01

The toxin components of toxin-antitoxin modules, found in bacterial plasmids, phages, and chromosomes, typically target a single macromolecule to interfere with an essential cellular process. An apparent exception is the chromosomally encoded toxin component of the E. coli CbtA/CbeA toxin-antitoxin module, which can inhibit both cell division and cell elongation. A small protein of only 124 amino acids, CbtA, was previously proposed to interact with both FtsZ, a tubulin homolog that is essential for cell division, and MreB, an actin homolog that is essential for cell elongation. However, whether or not the toxic effects of CbtA are due to direct interactions with these predicted targets is not known. Here, we genetically separate the effects of CbtA on cell elongation and cell division, showing that CbtA interacts directly and independently with FtsZ and MreB. Using complementary genetic approaches, we identify the functionally relevant target surfaces on FtsZ and MreB, revealing that in both cases, CbtA binds to surfaces involved in essential cytoskeletal filament architecture. We show further that each interaction contributes independently to CbtA-mediated toxicity and that disruption of both interactions is required to alleviate the observed toxicity. Although several other protein modulators are known to target FtsZ, the CbtA-interacting surface we identify represents a novel inhibitory target. Our findings establish CbtA as a dual function toxin that inhibits both cell division and cell elongation via direct and independent interactions with FtsZ and MreB.

CbtA toxin of Escherichia coli inhibits cell division and cell elongation via direct and independent interactions with FtsZ and MreB

PubMed Central

Heller, Danielle M.; Tavag, Mrinalini

2017-01-01

The toxin components of toxin-antitoxin modules, found in bacterial plasmids, phages, and chromosomes, typically target a single macromolecule to interfere with an essential cellular process. An apparent exception is the chromosomally encoded toxin component of the E. coli CbtA/CbeA toxin-antitoxin module, which can inhibit both cell division and cell elongation. A small protein of only 124 amino acids, CbtA, was previously proposed to interact with both FtsZ, a tubulin homolog that is essential for cell division, and MreB, an actin homolog that is essential for cell elongation. However, whether or not the toxic effects of CbtA are due to direct interactions with these predicted targets is not known. Here, we genetically separate the effects of CbtA on cell elongation and cell division, showing that CbtA interacts directly and independently with FtsZ and MreB. Using complementary genetic approaches, we identify the functionally relevant target surfaces on FtsZ and MreB, revealing that in both cases, CbtA binds to surfaces involved in essential cytoskeletal filament architecture. We show further that each interaction contributes independently to CbtA-mediated toxicity and that disruption of both interactions is required to alleviate the observed toxicity. Although several other protein modulators are known to target FtsZ, the CbtA-interacting surface we identify represents a novel inhibitory target. Our findings establish CbtA as a dual function toxin that inhibits both cell division and cell elongation via direct and independent interactions with FtsZ and MreB. PMID:28931012

The ftsH gene of Bacillus subtilis is involved in major cellular processes such as sporulation, stress adaptation and secretion.

PubMed

Deuerling, E; Mogk, A; Richter, C; Purucker, M; Schumann, W

1997-03-01

The ftsH gene of Bacillus subtilis has been identified as a general stress gene which is transiently induced after thermal or osmotic upshift. The FtsH protein exhibits 70.1% homology to FtsH of Escherichia coli which constitutes an essential ATP- and Zn(2+)-dependent protease anchored in the cytoplasmic membrane via two N-terminal transmembrane domains. This paper describes the isolation and functional characterization of an ftsH null mutant which was obtained by integration of a cat-cassette near the 5' end of ftsH, thereby preventing the synthesis of FtsH protein. In contrast to the situation in E. coli, ftsH is dispensable in B. subtilis but results in a pleiotropic phenotype. While the mutant cells grew mostly as large filaments under physiological conditions, they turned out to be extremely sensitive to heat and salt stress. Although ftsH is necessary for adaptation to heat, it is not involved in the regulation of the heat-shock response. The induction profiles of representative genes of the CIRCE and sigma-B regulon and class III heat-shock genes ion and clpC were identical in the wild type and the ftsH null mutant. Furthermore, the ftsH knockout strain was unable to sporulate, and this failure was probably due to the absence of Spo0A protein which is essential for entry into the sporulation programme. In addition, secretion of bulk exoproteins was severely impaired in the ftsH null mutant after entry into stationary phase. The alpha-amylase and subtilisin activity in the supernatant was specifically tested. Whereas the activity of alpha-amylase increased after entry into stationary phase in both the wild type and the ftsH mutant strain, that of subtilisin encoded by aprE was prevented at the level of transcription in the mutant. Most of these results can be explained by the failure to synthesize appropriate amounts of Spo0A protein in the ftsH null mutant and point to ftsH as a developmental checkpoint.

Peptidoglycan synthesis drives an FtsZ-treadmilling-independent step of cytokinesis.

PubMed

Monteiro, João M; Pereira, Ana R; Reichmann, Nathalie T; Saraiva, Bruno M; Fernandes, Pedro B; Veiga, Helena; Tavares, Andreia C; Santos, Margarida; Ferreira, Maria T; Macário, Vânia; VanNieuwenhze, Michael S; Filipe, Sérgio R; Pinho, Mariana G

2018-02-22

Peptidoglycan is the main component of the bacterial wall and protects cells from the mechanical stress that results from high intracellular turgor. Peptidoglycan biosynthesis is very similar in all bacteria; bacterial shapes are therefore mainly determined by the spatial and temporal regulation of peptidoglycan synthesis rather than by the chemical composition of peptidoglycan. The form of rod-shaped bacteria, such as Bacillus subtilis or Escherichia coli, is generated by the action of two peptidoglycan synthesis machineries that act at the septum and at the lateral wall in processes coordinated by the cytoskeletal proteins FtsZ and MreB, respectively. The tubulin homologue FtsZ is the first protein recruited to the division site, where it assembles in filaments-forming the Z ring-that undergo treadmilling and recruit later divisome proteins. The rate of treadmilling in B. subtilis controls the rates of both peptidoglycan synthesis and cell division. The actin homologue MreB forms discrete patches that move circumferentially around the cell in tracks perpendicular to the long axis of the cell, and organize the insertion of new cell wall during elongation. Cocci such as Staphylococcus aureus possess only one type of peptidoglycan synthesis machinery, which is diverted from the cell periphery to the septum in preparation for division. The molecular cue that coordinates this transition has remained elusive. Here we investigate the localization of S. aureus peptidoglycan biosynthesis proteins and show that the recruitment of the putative lipid II flippase MurJ to the septum, by the DivIB-DivIC-FtsL complex, drives peptidoglycan incorporation to the midcell. MurJ recruitment corresponds to a turning point in cytokinesis, which is slow and dependent on FtsZ treadmilling before MurJ arrival but becomes faster and independent of FtsZ treadmilling after peptidoglycan synthesis activity is directed to the septum, where it provides additional force for cell envelope

Small molecule inhibition of apicomplexan FtsH1 disrupts plastid biogenesis in human pathogens.

PubMed

Amberg-Johnson, Katherine; Hari, Sanjay B; Ganesan, Suresh M; Lorenzi, Hernan A; Sauer, Robert T; Niles, Jacquin C; Yeh, Ellen

2017-08-18

The malaria parasite Plasmodium falciparum and related apicomplexan pathogens contain an essential plastid organelle, the apicoplast, which is a key anti-parasitic target. Derived from secondary endosymbiosis, the apicoplast depends on novel, but largely cryptic, mechanisms for protein/lipid import and organelle inheritance during parasite replication. These critical biogenesis pathways present untapped opportunities to discover new parasite-specific drug targets. We used an innovative screen to identify actinonin as having a novel mechanism-of-action inhibiting apicoplast biogenesis. Resistant mutation, chemical-genetic interaction, and biochemical inhibition demonstrate that the unexpected target of actinonin in P. falciparum and Toxoplasma gondii is FtsH1, a homolog of a bacterial membrane AAA+ metalloprotease. Pf FtsH1 is the first novel factor required for apicoplast biogenesis identified in a phenotypic screen. Our findings demonstrate that FtsH1 is a novel and, importantly, druggable antimalarial target. Development of FtsH1 inhibitors will have significant advantages with improved drug kinetics and multistage efficacy against multiple human parasites.

Understanding nucleotide-regulated FtsZ filament dynamics and the monomer assembly switch with large-scale atomistic simulations.

PubMed

Ramírez-Aportela, Erney; López-Blanco, José Ramón; Andreu, José Manuel; Chacón, Pablo

2014-11-04

Bacterial cytoskeletal protein FtsZ assembles in a head-to-tail manner, forming dynamic filaments that are essential for cell division. Here, we study their dynamics using unbiased atomistic molecular simulations from representative filament crystal structures. In agreement with experimental data, we find different filament curvatures that are supported by a nucleotide-regulated hinge motion between consecutive FtsZ monomers. Whereas GTP-FtsZ filaments bend and twist in a preferred orientation, thereby burying the nucleotide, the differently curved GDP-FtsZ filaments exhibit a heterogeneous distribution of open and closed interfaces between monomers. We identify a coordinated Mg(2+) ion as the key structural element in closing the nucleotide site and stabilizing GTP filaments, whereas the loss of the contacts with loop T7 from the next monomer in GDP filaments leads to open interfaces that are more prone to depolymerization. We monitored the FtsZ monomer assembly switch, which involves opening/closing of the cleft between the C-terminal domain and the H7 helix, and observed the relaxation of isolated and filament minus-end monomers into the closed-cleft inactive conformation. This result validates the proposed switch between the low-affinity monomeric closed-cleft conformation and the active open-cleft FtsZ conformation within filaments. Finally, we observed how the antibiotic PC190723 suppresses the disassembly switch and allosterically induces closure of the intermonomer interfaces, thus stabilizing the filament. Our studies provide detailed structural and dynamic insights into modulation of both the intrinsic curvature of the FtsZ filaments and the molecular switch coupled to the high-affinity end-wise association of FtsZ monomers.

Phenotypic indications of FtsZ inhibition in hok/sok-induced bacterial growth changes and stress response.

PubMed

Chukwudi, Chinwe Uzoma; Good, Liam

2018-01-01

The hok/sok locus has been shown to enhance the growth of bacteria in adverse growth conditions such as high temperature, low starting-culture densities and antibiotic treatment. This is in addition to their well-established plasmid-stabilization effect via post-segregational killing of plasmid-free daughter cells. It delays the onset of growth by prolonging the lag phase of bacterial culture, and increases the rate of exponential growth when growth eventually begins. This enables the cells adapt to the prevailing growth conditions and enhance their survival in stressful conditions. These effects functionally complement defective SOS response mechanism, and appear analogous to the growth effects of FtsZ in the SOS pathway. In this study, the role of FtsZ in the hok/sok-induced changes in bacterial growth and cell division was investigated. Morphologic studies of early growth-phase cultures and cells growing under temperature stress showed elongated cells typical of FtsZ inhibition/deficiency. Both ftsZ silencing and over-expression produced comparable growth effects in control cells, and altered the growth changes observed otherwise in the hok/sok + cells. These changes were diminished in SOS-deficient strain containing mutant FtsZ. The involvement of FtsZ in the hok/sok-induced growth changes may be exploited as drug target in host bacteria, which often propagate antibiotic resistance elements. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characteristics of greenhouse gas concentrations derived from ground-based FTS spectra at Anmyeondo, South Korea

NASA Astrophysics Data System (ADS)

Oh, Young-Suk; Takele Kenea, S.; Goo, Tae-Young; Chung, Kyu-Sun; Rhee, Jae-Sang; Ou, Mi-Lim; Byun, Young-Hwa; Wennberg, Paul O.; Kiel, Matthäus; DiGangi, Joshua P.; Diskin, Glenn S.; Velazco, Voltaire A.; Griffith, David W. T.

2018-04-01

Since the late 1990s, the meteorological observatory established in Anmyeondo (36.5382° N, 126.3311° E, and 30 m above mean sea level) has been monitoring several greenhouse gases such as CO2, CH4, N2O, CFCs, and SF6 as a part of the Global Atmosphere Watch (GAW) Program. A high resolution ground-based (g-b) Fourier transform spectrometer (FTS) was installed at this observation site in 2013 and has been operated within the frame work of the Total Carbon Column Observing Network (TCCON) since August 2014. The solar spectra recorded by the g-b FTS cover the spectral range 3800 to 16 000 cm-1 at a resolution of 0.02 cm-1. In this work, the GGG2014 version of the TCCON standard retrieval algorithm was used to retrieve total column average CO2 and CH4 dry mole fractions (XCO2, XCH4) and from the FTS spectra. Spectral bands of CO2 (at 6220.0 and 6339.5 cm-1 center wavenumbers, CH4 at 6002 cm-1 wavenumber, and O2 near 7880 cm-1 ) were used to derive the XCO2 and XCH4. In this paper, we provide comparisons of XCO2 and XCH4 between the aircraft observations and g-b FTS over Anmyeondo station. A comparison of 13 coincident observations of XCO2 between g-b FTS and OCO-2 (Orbiting Carbon Observatory) satellite measurements are also presented for the measurement period between February 2014 and November 2017. OCO-2 observations are highly correlated with the g-b FTS measurements (r2 = 0.884) and exhibited a small positive bias (0.189 ppm). Both data set capture seasonal variations of the target species with maximum and minimum values in spring and late summer, respectively. In the future, it is planned to further utilize the FTS measurements for the evaluation of satellite observations such as Greenhouse Gases Observing Satellite (GOSAT, GOSAT-2). This is the first report of the g-b FTS observations of XCO2 species over the Anmyeondo station.

Farnesylthiosalicylic acid sensitizes hepatocarcinoma cells to artemisinin derivatives

PubMed Central

Wu, Liping; Pang, Yilin; Qin, Guiqi; Xi, Gaina; Wu, Shengnan; Wang, Xiaoping; Chen, Tongsheng

2017-01-01

Dihydroartemisinin (DHA) and artesunate (ARS), two artemisinin derivatives, have efficacious anticancer activities against human hepatocarcinoma (HCC) cells. This study aims to study the anticancer action of the combination treatment of DHA/ARS and farnesylthiosalicylic acid (FTS), a Ras inhibitor, in HCC cells (Huh-7 and HepG2 cell lines). FTS pretreatment significantly enhanced DHA/ARS-induced phosphatidylserine (PS) externalization, Bak/Bax activation, mitochondrial membrane depolarization, cytochrome c release, and caspase-8 and -9 activations, characteristics of the extrinsic and intrinsic apoptosis. Pretreatment with Z-IETD-FMK (caspase-8 inhibitor) potently prevented the cytotoxicity of the combination treatment of DHA/ARS and FTS, and pretreatment with Z-VAD-FMK (pan-caspase inhibitor) significantly inhibited the loss of ΔΨm induced by DHA/ARS treatment or the combination treatment of DHA/ARS and FTS in HCC cells. Furthermore, silencing Bak/Bax modestly but significantly inhibited the cytotoxicity of the combination treatment of DHA/ARS and FTS. Interestingly, pretreatment with an antioxidant N-Acetyle-Cysteine (NAC) significantly prevented the cytotoxicity of the combination treatment of DHA and FTS instead of the combination treatment of ARS and FTS, suggesting that reactive oxygen species (ROS) played a key role in the anticancer action of the combination treatment of DHA and FTS. Similar to FTS, DHA/ARS also significantly prevented Ras activation. Collectively, our data demonstrate that FTS potently sensitizes Huh-7 and HepG2 cells to artemisinin derivatives via accelerating the extrinsic and intrinsic apoptotic pathways. PMID:28182780

Structural insights of Staphylococcus aureus FtsZ inhibitors through molecular docking, 3D-QSAR and molecular dynamics simulations.

PubMed

Ballu, Srilata; Itteboina, Ramesh; Sivan, Sree Kanth; Manga, Vijjulatha

2018-02-01

Filamentous temperature-sensitive protein Z (FtsZ) is a protein encoded by the FtsZ gene that assembles into a Z-ring at the future site of the septum of bacterial cell division. Structurally, FtsZ is a homolog of eukaryotic tubulin but has low sequence similarity; this makes it possible to obtain FtsZ inhibitors without affecting the eukaryotic cell division. Computational studies were performed on a series of substituted 3-arylalkoxybenzamide derivatives reported as inhibitors of FtsZ activity in Staphylococcus aureus. Quantitative structure-activity relationship models (QSAR) models generated showed good statistical reliability, which is evident from r 2 ncv and r 2 loo values. The predictive ability of these models was determined and an acceptable predictive correlation (r 2 Pred ) values were obtained. Finally, we performed molecular dynamics simulations in order to examine the stability of protein-ligand interactions. This facilitated us to compare free binding energies of cocrystal ligand and newly designed molecule B1. The good concordance between the docking results and comparative molecular field analysis (CoMFA)/comparative molecular similarity indices analysis (CoMSIA) contour maps afforded obliging clues for the rational modification of molecules to design more potent FtsZ inhibitors.

Elevated guanosine 5'-diphosphate 3'-diphosphate level inhibits bacterial growth and interferes with FtsZ assembly.

PubMed

Yamaguchi, Takayoshi; Iida, Ken-Ichiro; Shiota, Susumu; Nakayama, Hiroaki; Yoshida, Shin-Ichi

2015-12-01

FtsZ, a protein essential for prokaryotic cell division, forms a ring structure known as the Z-ring at the division site. FtsZ has a GTP binding site and is assembled into linear structures in a GTP-dependent manner in vitro. We assessed whether guanosine 5'-diphosphate 3'-diphosphate (ppGpp), a global regulator of gene expression in starved bacteria, affects cell division in Salmonella Paratyphi A. Elevation of intracellular ppGpp levels by using the relA expression vector induced repression of bacterial growth and incorrect FtsZ assembly. We found that FtsZ forms helical structures in the presence of ppGpp by using the GTP binding site; however, ppGpp levels required to form helical structures were at least 20-fold higher than the required GTP levels in vitro. Furthermore, once formed, helical structures did not change to the straight form even after GTP addition. Our data indicate that elevation of the ppGpp level leads to inhibition of bacterial growth and interferes with FtsZ assembly. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Antibacterial Cell Division Inhibitor PC190723 Is an FtsZ Polymer-stabilizing Agent That Induces Filament Assembly and Condensation*

PubMed Central

Andreu, José M.; Schaffner-Barbero, Claudia; Huecas, Sonia; Alonso, Dulce; Lopez-Rodriguez, María L.; Ruiz-Avila, Laura B.; Núñez-Ramírez, Rafael; Llorca, Oscar; Martín-Galiano, Antonio J.

2010-01-01

Cell division protein FtsZ can form single-stranded filaments with a cooperative behavior by self-switching assembly. Subsequent condensation and bending of FtsZ filaments are important for the formation and constriction of the cytokinetic ring. PC190723 is an effective bactericidal cell division inhibitor that targets FtsZ in the pathogen Staphylococcus aureus and Bacillus subtilis and does not affect Escherichia coli cells, which apparently binds to a zone equivalent to the binding site of the antitumor drug taxol in tubulin (Haydon, D. J., Stokes, N. R., Ure, R., Galbraith, G., Bennett, J. M., Brown, D. R., Baker, P. J., Barynin, V. V., Rice, D. W., Sedelnikova, S. E., Heal, J. R., Sheridan, J. M., Aiwale, S. T., Chauhan, P. K., Srivastava, A., Taneja, A., Collins, I., Errington, J., and Czaplewski, L. G. (2008) Science 312, 1673–1675). We have found that the benzamide derivative PC190723 is an FtsZ polymer-stabilizing agent. PC190723 induced nucleated assembly of Bs-FtsZ into single-stranded coiled protofilaments and polymorphic condensates, including bundles, coils, and toroids, whose formation could be modulated with different solution conditions. Under conditions for reversible assembly of Bs-FtsZ, PC190723 binding reduced the GTPase activity and induced the formation of straight bundles and ribbons, which was also observed with Sa-FtsZ but not with nonsusceptible Ec-FtsZ. The fragment 2,6-difluoro-3-methoxybenzamide also induced Bs-FtsZ bundling. We propose that polymer stabilization by PC190723 suppresses in vivo FtsZ polymer dynamics and bacterial division. The biochemical action of PC190723 on FtsZ parallels that of the microtubule-stabilizing agent taxol on the eukaryotic structural homologue tubulin. Both taxol and PC190723 stabilize polymers against disassembly by preferential binding to each assembled protein. It is yet to be investigated whether both ligands target structurally related assembly switches. PMID:20212044

Regulation of transcription of the cell division gene ftsA during sporulation of Bacillus subtilis.

PubMed Central

Gholamhoseinian, A; Shen, Z; Wu, J J; Piggot, P

1992-01-01

Three distinct 5' ends of ftsA mRNA were identified by S1 mapping and by primer extension analysis. These are thought to represent three transcription start sites. The transcripts from the downstream and upstream sites were detected throughout growth. The transcript from the middle site was not detected during exponential growth but was detected within 30 min of the start of sporulation, when it was the predominant transcript. Insertion of a cat cassette in the middle promoter, ftsAp2 (p2), did not affect vegetative growth but prevented postexponential symmetrical division and spore formation. Transcription from p2 was dependent on RNA polymerase containing sigma H, and promoter p2 resembled the consensus sigma H promoter. Transcription from p2 did not require expression of the spo0A, spo0B, spo0E, spo0F, or spo0K loci. Northern (RNA) blot analysis indicated that ftsA is cotranscribed with the adjacent ftsZ gene. Multiple promoters provide a mechanism by which essential vegetative genes can be subjected to sporulation control independent of control during vegetative growth. In the case of ftsA,Z, the promoters provide a mechanism to permit septum formation in conditions of nutrient depletion that might be expected to shut down the vegetative division machinery. Images PMID:1624452

SAR Studies on Trisubstituted Benzimidazoles as Inhibitors of Mtb FtsZ for the Development of Novel Antitubercular Agents

PubMed Central

Awasthi, Divya; Kumar, Kunal; Knudson, Susan E.; Slayden, Richard A.; Ojima, Iwao

2014-01-01

FtsZ, an essential protein for bacterial cell division, is a highly promising therapeutic target, especially for the discovery and development of new-generation anti-TB agents. Following up the identification of two lead 2,5,6-trisubstituted benzimidazoles, 1 and 2, targeting Mtb-FtsZ in our previous study, an extensive SAR study for optimization of these lead compounds was performed through systematic modification of the 5 and 6 positions. This study has successfully led to the discovery of a highly potent advanced lead 5f (MIC 0.06 µg/mL) and several other compounds with comparable potencies. These advanced lead compounds possess a dimethylamino group at the 6 position. The functional groups at the 5 position exhibit substantial effects on the antibacterial activity as well. In vitro experiments such as the FtsZ polymerization inhibitory assay and TEM analysis of Mtb-FtsZ treated with 5f and others indicate that Mtb-FtsZ is the molecular target for their antibacterial activity. PMID:24266862

SAR studies on trisubstituted benzimidazoles as inhibitors of Mtb FtsZ for the development of novel antitubercular agents.

PubMed

Awasthi, Divya; Kumar, Kunal; Knudson, Susan E; Slayden, Richard A; Ojima, Iwao

2013-12-12

FtsZ, an essential protein for bacterial cell division, is a highly promising therapeutic target, especially for the discovery and development of new-generation anti-TB agents. Following up the identification of two lead 2,5,6-trisubstituted benzimidazoles, 1 and 2, targeting Mtb-FtsZ in our previous study, an extensive SAR study for optimization of these lead compounds was performed through systematic modification of the 5 and 6 positions. This study has successfully led to the discovery of a highly potent advanced lead 5f (MIC = 0.06 μg/mL) and several other compounds with comparable potencies. These advanced lead compounds possess a dimethylamino group at the 6 position. The functional groups at the 5 position exhibit substantial effects on the antibacterial activity as well. In vitro experiments such as the FtsZ polymerization inhibitory assay and TEM analysis of Mtb-FtsZ treated with 5f and others indicate that Mtb-FtsZ is the molecular target for their antibacterial activity.

Performance of the Fourier transform spectrometer (FTS) for FIS onboard ASTRO-F

NASA Astrophysics Data System (ADS)

Murakami, Noriko; Kawada, Mitsunobu; Takahashi, Hidenori; Ozawa, Keita; Imamura, Tetsuo; Shibai, Hiroshi; Nakagawa, Takao

2004-10-01

We have developed the imaging Fourier Transform Spectrometer (FTS) for the FIS (Far-Infrared Surveyor) onboard the ASTRO-F satellite. A Martin-Puplett interferometer is adopted to achieve high optical efficiency in a wide wavelength range. The total optical efficiency of this spectrometer is achieved 40-80% of the ideal value which is 25% of the incident flux. The wavelength range of 50-200μm is covered with two kinds of detector; the monolithic Ge:Ga photoconductor array for short wavelength (50-110μm) and the stressed Ge:Ga photoconductor array for long wavelength (110-200μm). The spectral resolution expected from the maximum optical path difference is 0.18cm-1. In order to evaluate the spectral resolution of the FTS, we measured absorption lines of H2O in atmosphere using the optics of the FTS with a bolometer at the room temperature. The measured line widths are consistent with the expected instrumental resolution of 0.18 cm-1. Some spectral measurements at the cryogenic temperature were carried out by using cold blackbody sources whose temperatures are controlled in a range from 20 to 50 K. The derived spectra considering with the spectral response of the system are consistent with expected ones. Spectroscopic observations with the FTS will provide a lot of astronomical information; SED of galaxies detected in the all sky survey and the physical diagnostics of the interstellar matter by using the excited atomic or molecular lines.

FTS: Fourier transform spectrometer onboard ASTRO-F/FIS

NASA Astrophysics Data System (ADS)

Takahashi, Hidenori; Kawada, Mitsunobu; Murakami, Noriko; Ozawa, Keita; Shibai, Hiroshi; Nakagawa, Takao

2003-03-01

Far-Infrared Surveyor (FIS) is one of the two focal plane instruments of ASTRO-F which is a Japanese infrared astronomical satellite and is planned to launch in 2004. The FIS has spectroscopic capability by a Fourier transform spectrometer (FTS) covering 50-200cm-1 with spectral resolution of 0.2-0.33 cm-1 in addition to the primary purpose of FIS (an all-sky photometric survey). The Martin-Puplett interferometer is adopted as the method for spectroscopy in order to achieve high optical efficiency in a wide wavelength range. The most important issue of the FTS is the development of driving mechanism in order to scan a moving mirror with high optical performances. By the present we succeed to develop the driving mechanism satisfying a lot of limitations and requirements as a instrument onboard satellite. Furthermore the wire-grid polarizers are evaluated in optical performance, these are usable for polarized interferomter. We also measure FIR spectrum using Spectroscopy mode of FIS, and many absorption lines of H2O are detected on continuum spectrum of atmosphere. And the interferogram and spectrum are derived at low temperature (2K) that is practically used in space. The spectrum resembles expected one which are considered with optical components for flight model. The detection limit are estimated combining performances of optical components and detectors, the FISP has sufficient performance to archive objective sciences. FTS will provide a lot of astronomical information; determination of the SED in high-z objects detected by the survey observation of ASTRO-F, the redshift of such objects, and the physical conditions that are hard to be derived by optical/NIR-MIR observations, from FIR lines.

Performance Verification of GOSAT-2 FTS-2 Simulator and Sensitivity Analysis for Greenhouse Gases Retrieval

NASA Astrophysics Data System (ADS)

Kamei, A.; Yoshida, Y.; Dupuy, E.; Hiraki, K.; Matsunaga, T.

2015-12-01

The GOSAT-2, which is scheduled for launch in early 2018, is the successor mission to the Greenhouse gases Observing Satellite (GOSAT). The FTS-2 onboard the GOSAT-2 is a Fourier transform spectrometer, which has three bands in the near to short-wavelength infrared (SWIR) region and two bands in the thermal infrared (TIR) region to observe infrared light reflected and emitted from the Earth's surface and atmosphere with high-resolution spectra. Column amounts and vertical profiles of major greenhouse gases such as carbon dioxide (CO2) and methane (CH4) are retrieved from acquired radiance spectra. In addition, the FTS-2 has several improvements from the FTS onboard the GOSAT: 1) added spectral coverage in the SWIR region for carbon monoxide (CO) retrieval, 2) increased signal-to-noise ratio (SNR) for all bands, 3) extended range of along-track pointing angles for sunglint observations, 4) intelligent pointing to avoid cloud contamination. Since 2012, we have been developing a software tool, which is called the GOSAT-2 FTS-2 simulator, to simulate spectral radiance data that will be acquired by the GOSAT-2 FTS-2. The objective of it is to analyze/optimize data with respect to the sensor specification, the parameters for Level 1 processing, and the improvement of Level 2 retrieval algorithms. It consists of six components: 1) overall control, 2) sensor carrying platform, 3) spectral radiance calculation, 4) Fourier transform module, 5) Level 1B (L1B) processing, and 6) L1B data output. More realistic and faster simulations have been made possible by the improvement of details about sensor characteristics, the sophistication of data processing and algorithms, the addition of various observation modes, the use of surface and atmospheric ancillary data, and the speed-up and parallelization of radiative transfer code. This simulator is confirmed to be working properly from the reproduction of GOSAT FTS L1B data depends on the ancillary data. We will summarize the

Characterization of TANSO-FTS on GOSAT

NASA Astrophysics Data System (ADS)

Suto, H.; Kuze, A.; Kaneko, Y.; Hamazaki, T.

2006-12-01

In order to measure the global column concentration of carbon dioxide (CO2) and methane (CH4), the Green house gases Observing SATellite (GOSAT) will be planning to launch at August in 2008. To estimate and demonstrate the performance of TANSO-FTS (Thermal And Near infrared Sensor for carbon Observation Fourier-Transform Spectrometer) through the filed and laboratory experiments, the Bread Board Model (BBM) for TANSO-FTS has been developed. The BBM has three narrow bands detectable regions; 0.76, 1.6 and 2micrion (band1,2 and 3) with +/-2.5cm maximum optical path difference. The Signal to Noise ratio (SNR), response and the instrumental line shape (ILS) have been determined in the laboratory by introducing the light emitted from the black body, Ar lamp, and the tunable diode laser. The measured values of full width at half maximum (FWHM) are 0.35, 0.25, 0.24 cm-1 for band1, 2 and 3, respectively. Also, the measured ILS has good correlation with the calculated one, and the parameterization of off-axis effect has been investigated. The developed method will be applied to determine the characterization of Engineering Model (EM) and Proto Flight Model (PFM) of TANSO. In this presentation, the characterization of TANSO-BBM and the preliminary results of performance test as well as TANSO-EM will be reported.

Thermal stability control system of photo-elastic interferometer in the PEM-FTs

NASA Astrophysics Data System (ADS)

Zhang, M. J.; Jing, N.; Li, K. W.; Wang, Z. B.

2018-01-01

A drifting model for the resonant frequency and retardation amplitude of a photo-elastic modulator (PEM) in the photo-elastic modulated Fourier transform spectrometer (PEM-FTs) is presented. A multi-parameter broadband-matching driving control method is proposed to improve the thermal stability of the PEM interferometer. The automatically frequency-modulated technology of the driving signal based on digital phase-locked technology is used to track the PEM's changing resonant frequency. Simultaneously the maximum optical-path-difference of a laser's interferogram is measured to adjust the amplitude of the PEM's driving signal so that the spectral resolution is stable. In the experiment, the multi-parameter broadband-matching control method is applied to the driving control system of the PEM-FTs. Control of resonant frequency and retardation amplitude stabilizes the maximum optical-path-difference to approximately 236 μm and results in a spectral resolution of 42 cm-1. This corresponds to a relative error smaller than 2.16% (4.28 standard deviation). The experiment shows that the method can effectively stabilize the spectral resolution of the PEM-FTs.

Straight and Curved Conformations of FtsZ Are Regulated by GTP Hydrolysis

PubMed Central

Lu, Chunlin; Reedy, Mary; Erickson, Harold P.

2000-01-01

FtsZ assembles in vitro into protofilaments that can adopt two conformations—the straight conformation, which can assemble further into two-dimensional protofilament sheets, and the curved conformation, which forms minirings about 23 nm in diameter. Here, we describe the structure of FtsZ tubes, which are a variation of the curved conformation. In the tube the curved protofilament forms a shallow helix with a diameter of 23 nm and a pitch of 18 or 24°. We suggest that this shallow helix is the relaxed structure of the curved protofilament in solution. We provide evidence that GTP favors the straight conformation while GDP favors the curved conformation. In particular, exclusively straight protofilaments and protofilament sheets are assembled in GMPCPP, a nonhydrolyzable GTP analog, or in GTP following chelation of Mg, which blocks GTP hydrolysis. Assembly in GDP produces exclusively tubes. The transition from straight protofilaments to the curved conformation may provide a mechanism whereby the energy of GTP hydrolysis is used to generate force for the constriction of the FtsZ ring in cell division. PMID:10613876

Site-directed fluorescence labeling reveals a revised N-terminal membrane topology and functional periplasmic residues in the Escherichia coli cell division protein FtsK.

PubMed

Berezuk, Alison M; Goodyear, Mara; Khursigara, Cezar M

2014-08-22

In Escherichia coli, FtsK is a large integral membrane protein that coordinates chromosome segregation and cell division. The N-terminal domain of FtsK (FtsKN) is essential for division, and the C terminus (FtsKC) is a well characterized DNA translocase. Although the function of FtsKN is unknown, it is suggested that FtsK acts as a checkpoint to ensure DNA is properly segregated before septation. This may occur through modulation of protein interactions between FtsKN and other division proteins in both the periplasm and cytoplasm; thus, a clear understanding of how FtsKN is positioned in the membrane is required to characterize these interactions. The membrane topology of FtsKN was initially determined using site-directed reporter fusions; however, questions regarding this topology persist. Here, we report a revised membrane topology generated by site-directed fluorescence labeling. The revised topology confirms the presence of four transmembrane segments and reveals a newly identified periplasmic loop between the third and fourth transmembrane domains. Within this loop, four residues were identified that, when mutated, resulted in the appearance of cellular voids. High resolution transmission electron microscopy of these voids showed asymmetric division of the cytoplasm in the absence of outer membrane invagination or visible cell wall ingrowth. This uncoupling reveals a novel role for FtsK in linking cell envelope septation events and yields further evidence for FtsK as a critical checkpoint of cell division. The revised topology of FtsKN also provides an important platform for future studies on essential interactions required for this process. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Direct interaction of FtsZ and MreB is required for septum synthesis and cell division in Escherichia coli.

PubMed

Fenton, Andrew K; Gerdes, Kenn

2013-07-03

How bacteria coordinate cell growth with division is not well understood. Bacterial cell elongation is controlled by actin-MreB while cell division is governed by tubulin-FtsZ. A ring-like structure containing FtsZ (the Z ring) at mid-cell attracts other cell division proteins to form the divisome, an essential protein assembly required for septum synthesis and cell separation. The Z ring exists at mid-cell during a major part of the cell cycle without contracting. Here, we show that MreB and FtsZ of Escherichia coli interact directly and that this interaction is required for Z ring contraction. We further show that the MreB-FtsZ interaction is required for transfer of cell-wall biosynthetic enzymes from the lateral to the mature divisome, allowing cells to synthesise the septum. Our observations show that bacterial cell division is coupled to cell elongation via a direct and essential interaction between FtsZ and MreB.

Direct interaction of FtsZ and MreB is required for septum synthesis and cell division in Escherichia coli

PubMed Central

Fenton, Andrew K; Gerdes, Kenn

2013-01-01

How bacteria coordinate cell growth with division is not well understood. Bacterial cell elongation is controlled by actin–MreB while cell division is governed by tubulin–FtsZ. A ring-like structure containing FtsZ (the Z ring) at mid-cell attracts other cell division proteins to form the divisome, an essential protein assembly required for septum synthesis and cell separation. The Z ring exists at mid-cell during a major part of the cell cycle without contracting. Here, we show that MreB and FtsZ of Escherichia coli interact directly and that this interaction is required for Z ring contraction. We further show that the MreB–FtsZ interaction is required for transfer of cell-wall biosynthetic enzymes from the lateral to the mature divisome, allowing cells to synthesise the septum. Our observations show that bacterial cell division is coupled to cell elongation via a direct and essential interaction between FtsZ and MreB. PMID:23756461

Adaptation of a military FTS to civilian air toxics measurements

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

Engel, J.R.; Dorval, R.K.

1994-12-31

In many ways, the military problem of chemical agent detection is similar to the civilian problem of toxic and related air pollutants detection. A recent program to design a next generation Fourier transform spectrometer (FTS) based chemical agent detection system has been funded by the US Army. This program has resulted in an FTS system that has a number of characteristics that make it suitable for applications to the civilian measurement problem. Low power, low weight, and small size lead to low installation, operating and maintenance costs. Innovative use of diode lasers in place of HeNe reference sources leads tomore » long lifetimes and high reliability. Absolute scan position servos allow for highly efficient offset scanning. This paper will relate the performance of this system to present air monitoring requirements.« less

Studies on the Dissociation and Urea-Induced Unfolding of FtsZ Support the Dimer Nucleus Polymerization Mechanism

PubMed Central

Montecinos-Franjola, Felipe; Ross, Justin A.; Sánchez, Susana A.; Brunet, Juan E.; Lagos, Rosalba; Jameson, David M.; Monasterio, Octavio

2012-01-01

FtsZ is a major protein in bacterial cytokinesis that polymerizes into single filaments. A dimer has been proposed to be the nucleating species in FtsZ polymerization. To investigate the influence of the self-assembly of FtsZ on its unfolding pathway, we characterized its oligomerization and unfolding thermodynamics. We studied the assembly using size-exclusion chromatography and fluorescence spectroscopy, and the unfolding using circular dichroism and two-photon fluorescence correlation spectroscopy. The chromatographic analysis demonstrated the presence of monomers, dimers, and tetramers with populations dependent on protein concentration. Dilution experiments using fluorescent conjugates revealed dimer-to-monomer and tetramer-to-dimer dissociation constants in the micromolar range. Measurements of fluorescence lifetimes and rotational correlation times of the conjugates supported the presence of tetramers at high protein concentrations and monomers at low protein concentrations. The unfolding study demonstrated that the three-state unfolding of FtsZ was due to the mainly dimeric state of the protein, and that the monomer unfolds through a two-state mechanism. The monomer-to-dimer equilibrium characterized here (Kd = 9 μM) indicates a significant fraction (∼10%) of stable dimers at the critical concentration for polymerization, supporting a role of the dimeric species in the first steps of FtsZ polymerization. PMID:22824282

CARVE-FTS observations of arctic CO2, CH4, and CO: overview of the instrument

NASA Astrophysics Data System (ADS)

Dupont, Fabien; Tanguay, François; Li, Manyuan; Perron, Gaetan; Miller, Charles E.; Dinardo, Steven J.; Kurosu, Thomas P.

2012-09-01

CARVE-FTS is a near-IR Fourier-Transform Spectrometer (FTS) used by the Jet Propulsion Laboratory (JPL) for the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE). CARVE is a 5-year mission of intensive aircraft campaigns in the Alaskan Arctic selected as part of NASA's Earth Ventures program (EV-1). The CARVE-FTS has been designed, manufactured and tested by ABB Inc. The objective of this instrument is to provide integrated column measurements of carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO). The system is inspired from the TSUKUBA-FTS built by ABB for the Japanese Aerospace Exploration Agency (JAXA). JAXA uses the instrument for preparation, calibration and validation within the GOSAT program. The instrument is a Michelson based FTS with three spectral bands. The light modulator is a Michelson single pass type interferometer with large aperture and medium spectral resolution. It provides infrared spectra from 12,900 cm-1 to 13,200 cm-1, from 5,800 cm-1 to 6,400 cm-1, and from 4,200 cm-1 to 4,900 cm-1. This instrument is also able to measure the scene radiance with S and P polarization simultaneously using monopixel detectors. The instrument is mounted on a damping platform and is installed in an aircraft. It delivers continuous data for flight campaigns over the Alaskan Arctic. SNR higher than 100 is reached for each band and the measured ILS full width at half maximum is as low as 0.26 cm-1 at 6,566 cm-1. We present the instrument design, its specification and test results obtained at ABB.

Relationship between a spleen-derived immunosuppressive peptide 'SDIP' and the 'Facteur thymique sérique' (FTS): biochemical and biological comparison of the two factors.

PubMed Central

Lenfant, M; Millerioux, L; Blazsek, I; Duchange, N

1983-01-01

A spleen-derived immunosuppressive peptide (SDIP) has been purified to homogeneity. Its physicochemical properties (electrophoretic mobility, u.v. spectra, absence of dansyl derivative) and its enzymatic susceptibilities (proteolytic enzymes, RNase, and DNase) were similar to those of the thymic hormone 'FTS'. SDIP and FTS were eluted with identical retention times in high performance liquid chromatography analysis in three different systems. When tested in sheep cell rosettes, and in the FTS radioimmunoassay in J.F. Bach's laboratory, SDIP presented an activity similar to FTS. In order to compare the thymic hormone to SDIP the biological activity of FTS was determined in in vivo and in in vitro humoral immunity reactions to a T-dependent antigen. As SDIP, FTS inhibited in vivo and in vitro the 19S-bearing cell formation during the last step of the differentiation of the lymphocytes, in the same range of concentration. The two factors appeared to stimulate the incorporation of [3H]-thymidine into the DNA of short-term cultures of thymocytes. The similarity of biological properties of SDIP and FTS together with the similarity observed in the physico-chemical and biochemical properties led to the conclusion that bovine spleen contains a factor similar to FTS. PMID:6682089

Chloroplast targeting of FtsHprotease is essential for chloroplast development and thylakoid stability at elevated temperatures in plants

USDA-ARS?s Scientific Manuscript database

AtFtsH11 is a chloroplast and mitochondria dual targeted metalloprotease, identified as essential for Arabidopsis plant to survive at moderate high temperatures at all developmental stages. Our study showed that FtsH11 plays critical roles in both the early stages of chloroplast biogenesis and main...

Spectral Characterizations of the Clouds and the Earth's Radiant Energy System (CERES) Thermistor Bolometers using Fourier Transform Spectrometer (FTS) Techniques

NASA Technical Reports Server (NTRS)

Thornhill, K. Lee; Bitting, Herbert; Lee, Robert B., III; Paden, Jack; Pandey, Dhirendra K.; Priestley, Kory J.; Thomas, Susan; Wilson, Robert S.

1998-01-01

Fourier Transform Spectrometer (FTS) techniques are being used to characterize the relative spectral response, or sensitivity, of scanning thermistor bolometers in the infrared (IR) region (2 - >= 100-micrometers). The bolometers are being used in the Clouds and the Earth's Radiant Energy System (CERES) program. The CERES measurements are designed to provide precise, long term monitoring of the Earth's atmospheric radiation energy budget. The CERES instrument houses three bolometric radiometers, a total wavelength (0.3- >= 150-micrometers) sensor, a shortwave (0.3-5-micrometers) sensor, and an atmospheric window (8-12-micrometers) sensor. Accurate spectral characterization is necessary for determining filtered radiances for longwave radiometric calibrations. The CERES bolometers spectral response's are measured in the TRW FTS Vacuum Chamber Facility (FTS - VCF), which uses a FTS as the source and a cavity pyroelectric trap detector as the reference. The CERES bolometers and the cavity detector are contained in a vacuum chamber, while the FTS source is housed in a GN2 purged chamber. Due to the thermal time constant of the CERES bolometers, the FTS must be operated in a step mode. Data are acquired in 6 IR spectral bands covering the entire longwave IR region. In this paper, the TRW spectral calibration facility design and data measurement techniques are described. Two approaches are presented which convert the total channel FTS data into the final CERES spectral characterizations, producing the same calibration coefficients (within 0.1 percent). The resulting spectral response curves are shown, along with error sources in the two procedures. Finally, the impact of each spectral response curve on CERES data validation will be examined through analysis of filtered radiance values from various typical scene types.

In vitro induction of monoclonal antibody-defined T-cell markers in lymphocytes from immunodeficient children by synthetic serum thymic factor (FTS).

PubMed Central

Bene, M C; Faure, G; Bordigoni, P; Olive, D; Duheille, J

1982-01-01

Lymphocytes from five children suffering from ataxia telangectasia or various unclassified immune deficiencies were tested in vitro for their sensitivity to synthetic serum thymic factor (FTS). The percentages of cells bearing T cell markers were elevated after incubation with FTS at graded concentrations (0.25, 2.5 and 25 ng/ml), by microlymphocytotoxicity or indirect immunofluorescence, using monoclonal anti-Lyt1 antibodies. In four cases, more than 30% of the non-T non-B cells acquired the Lyt1 T cell marker. These four children had low levels of circulating FTS. In the fifth child, who had a normal serum FTS level, and in two age-matched controls, there was no significant increase in the percentage of cells bearing the T marker. PMID:7049454

Calculations of binding affinity between C8-substituted GTP analogs and the bacterial cell-division protein FtsZ

PubMed Central

Hritz, Jozef; Läppchen, Tilman

2010-01-01

The FtsZ protein is a self-polymerizing GTPase that plays a central role in bacterial cell division. Several C8-substituted GTP analogs are known to inhibit the polymerization of FtsZ by competing for the same binding site as its endogenous activating ligand GTP. Free energy calculations of the relative binding affinities to FtsZ for a set of five C8-substituted GTP analogs were performed. The calculated values agree well with the available experimental data, and the main contribution to the free energy differences is determined to be the conformational restriction of the ligands. The dihedral angle distributions around the glycosidic bond of these compounds in water are known to vary considerably depending on the physicochemical properties of the substituent at C8. However, within the FtsZ protein, this substitution has a negligible influence on the dihedral angle distributions, which fall within the narrow range of −140° to −90° for all investigated compounds. The corresponding ensemble average of the coupling constants 3J(C4,H1′) is calculated to be 2.95 ± 0.1 Hz. The contribution of the conformational selection of the GTP analogs upon binding was quantified from the corresponding populations. The obtained restraining free energy values follow the same trend as the relative binding affinities to FtsZ, indicating their dominant contribution. PMID:20559630

Is ftsH the Key to Plastid Longevity in Sacoglossan Slugs?

PubMed Central

de Vries, Jan; Habicht, Jörn; Woehle, Christian; Huang, Changjie; Christa, Gregor; Wägele, Heike; Nickelsen, Jörg; Martin, William F.; Gould, Sven B.

2013-01-01

Plastids sequestered by sacoglossan sea slugs have long been a puzzle. Some sacoglossans feed on siphonaceous algae and can retain the plastids in the cytosol of their digestive gland cells. There, the stolen plastids (kleptoplasts) can remain photosynthetically active in some cases for months. Kleptoplast longevity itself challenges current paradigms concerning photosystem turnover, because kleptoplast photosystems remain active in the absence of nuclear algal genes. In higher plants, nuclear genes are essential for plastid maintenance, in particular, for the constant repair of the D1 protein of photosystem II. Lateral gene transfer was long suspected to underpin slug kleptoplast longevity, but recent transcriptomic and genomic analyses show that no algal nuclear genes are expressed from the slug nucleus. Kleptoplast genomes themselves, however, appear expressed in the sequestered state. Here we present sequence data for the chloroplast genome of Acetabularia acetabulum, the food source of the sacoglossan Elysia timida, which can maintain Acetabularia kleptoplasts in an active state for months. The data reveal what might be the key to sacoglossan kleptoplast longevity: plastids that remain photosynthetically active within slugs for periods of months share the property of encoding ftsH, a D1 quality control protease that is essential for photosystem II repair. In land plants, ftsH is always nuclear encoded, it was transferred to the nucleus from the plastid genome when Charophyta and Embryophyta split. A replenishable supply of ftsH could, in principle, rescue kleptoplasts from D1 photodamage, thereby influencing plastid longevity in sacoglossan slugs. PMID:24336424

Constitutive expression of ftsZ overrides the whi developmental genes to initiate sporulation of Streptomyces coelicolor.

PubMed

Willemse, Joost; Mommaas, A Mieke; van Wezel, Gilles P

2012-03-01

The filamentous soil bacteria Streptomyces undergo a highly complex developmental programme. Before streptomycetes commit themselves to sporulation, distinct morphological checkpoints are passed in the aerial hyphae that are subject to multi-level control by the whi sporulation genes. Here we show that whi-independent expression of FtsZ restores sporulation to the early sporulation mutants whiA, whiB, whiG, whiH, whiI and whiJ. Viability, stress resistance and high-resolution electron microscopy underlined that viable spores were formed. However, spores from sporulation-restored whiA and whiG mutants showed defects in DNA segregation/condensation, while spores from the complemented whiB mutant had increased stress sensitivity, perhaps as a result of changes in the spore sheath. In contrast to the whi mutants, normal sporulation of ssgB null mutants-which fail to properly localise FtsZ-could not be restored by enhancing FtsZ protein levels, forming spore-like bodies that lack spore walls. Our data strongly suggest that the whi genes control a decisive event towards sporulation of streptomycetes, namely the correct timing of developmental ftsZ transcription. The biological significance may be to ensure that sporulation-specific cell division will only start once sufficient aerial mycelium biomass has been generated. Our data shed new light on the longstanding question as to how whi genes control sporulation, which has intrigued scientists for four decades.

Relating FTS Catalyst Properties to Performance

NASA Technical Reports Server (NTRS)

Ma, Wenping; Ramana Rao Pendyala, Venkat; Gao, Pei; Jermwongratanachai, Thani; Jacobs, Gary; Davis, Burton H.

2016-01-01

During the reporting period June 23, 2011 to August 31, 2013, CAER researchers carried out research in two areas of fundamental importance to the topic of cobalt-based Fischer-Tropsch Synthesis (FTS): promoters and stability. The first area was research into possible substitute promoters that might be used to replace the expensive promoters (e.g., Pt, Re, and Ru) that are commonly used. To that end, three separate investigations were carried out. Due to the strong support interaction of ?-Al2O3 with cobalt, metal promoters are commonly added to commercial FTS catalysts to facilitate the reduction of cobalt oxides and thereby boost active surface cobalt metal sites. To date, the metal promoters examined have been those up to and including Group 11. Because two Group 11 promoters (i.e., Ag and Au) were identified to exhibit positive impacts on conversion, selectivity, or both, research was undertaken to explore metals in Groups 12 - 14. The three metals selected for this purpose were Cd, In, and Sn. At a higher loading of 25%Co on alumina, 1% addition of Cd, In, or Sn was found to-on average-facilitate reduction by promoting a heterogeneous distribution of cobalt consisting of larger lesser interacting cobalt clusters and smaller strongly interacting cobalt species. The lesser interacting species were identified in TPR profiles, where a sharp low temperature peak occurred for the reduction of larger, weakly interacting, CoO species. In XANES, the Cd, In, and Sn promoters were found to exist as oxides, whereas typical promoters (e.g., Re, Ru, Pt) were previously determined to exist in an metallic state in atomic coordination with cobalt. The larger cobalt clusters significantly decreased the active site density relative to the unpromoted 25%Co/Al2O3 catalyst. Decreasing the cobalt loading to 15%Co eliminated the large non-interacting species. The TPR peak for reduction of strongly interacting CoO in the Cd promoted catalyst occurred at a measurably lower temperature

Strategic incorporation of fluorine in the drug discovery of new-generation antitubercular agents targeting bacterial cell division protein FtsZ⋆

PubMed Central

Ojima, Iwao; Awasthi, Divya; Wei, Longfei; Haranahalli, Krupanandan

2016-01-01

This article presents an account of our research on the discovery and development of new-generation fluorine-containing antibacterial agents against drug-resistant tuberculosis, targeting FtsZ. FtsZ is an essential protein for bacterial cell division and a highly promising therapeutic target for antibacterial drug discovery. Through design, synthesis and semi-HTP screening of libraries of novel benzimidazoles, followed by SAR studies, we identified highly potent lead compounds. However, these lead compounds were found to lack sufficient metabolic and plasma stabilities. Accordingly, we have performed extensive study on the strategic incorporation of fluorine into lead compounds to improve pharmacological properties. This study has led to the development of highly efficacious fluorine-containing benzimidazoles as potential drug candidates. We have also performed computational docking analysis of these novel FtsZ inhibitors to identify their putative binding site. Based on the structural data and docking analysis, a plausible mode-of-action for this novel class of FtsZ inhibitors is proposed. PMID:28555087

Design, Synthesis and Evaluation of Novel 2,5,6-Trisubstituted Benzimidazoles Targeting FtsZ as Antitubercular Agents

PubMed Central

Park, Bora; Awasthi, Divya; Chowdhury, Soumya R.; Melief, Eduard H.; Kumar, Kunal; Knudson, Susan E.; Slayden, Richard A.; Ojima, Iwao

2014-01-01

Filamenting temperature-sensitive protein Z (FtsZ), an essential cell division protein, is a promising target for the drug discovery of new-generation antibacterial agents against various bacterial pathogens. As a part of SAR studies on benzimidazoles, we have synthesized a library of 376 novel 2,5,6-trisubstituted benzimidazoles, bearing ether or thioether linkage at the 6-position. In a preliminary HTP screening against Mtb H37Rv, 108 compounds were identified as hits at a cut off concentration of 5 μg/mL. Among those hits, 10 compounds exhibited MIC values in the range of 0.63–12.5 μg/mL. Light scattering assay and TEM analysis with the most potent compound 5a clearly indicate that its molecular target is Mtb-FtsZ. Also, the Kd of 5a with Mtb-FtsZ was determined to be 1.32 μM. PMID:24726304

Demonstration of Imaging Fourier Transform Spectrometer (FTS) Performance for Planetary and Geostationary Earth Observing

NASA Technical Reports Server (NTRS)

Revercomb, Henry E.; Sromovsky, Lawrence A.; Fry, Patrick M.; Best, Fred A.; LaPorte, Daniel D.

2001-01-01

The combination of massively parallel spatial sampling and accurate spectral radiometry offered by imaging FTS makes it extremely attractive for earth and planetary remote sensing. We constructed a breadboard instrument to help assess the potential for planetary applications of small imaging FTS instruments in the 1 - 5 micrometer range. The results also support definition of the NASA Geostationary Imaging FTS (GIFTS) instrument that will make key meteorological and climate observations from geostationary earth orbit. The Planetary Imaging FTS (PIFTS) breadboard is based on a custom miniaturized Bomen interferometer that uses corner cube reflectors, a wishbone pivoting voice-coil delay scan mechanism, and a laser diode metrology system. The interferometer optical output is measured by a commercial infrared camera procured from Santa Barbara Focalplane. It uses an InSb 128x128 detector array that covers the entire FOV of the instrument when coupled with a 25 mm focal length commercial camera lens. With appropriate lenses and cold filters the instrument can be used from the visible to 5 micrometers. The delay scan is continuous, but slow, covering the maximum range of +/- 0.4 cm in 37.56 sec at a rate of 500 image frames per second. Image exposures are timed to be centered around predicted zero crossings. The design allows for prediction algorithms that account for the most recent fringe rate so that timing jitter produced by scan speed variations can be minimized. Response to a fixed source is linear with exposure time nearly to the point of saturation. Linearity with respect to input variations was demonstrated to within 0.16% using a 3-point blackbody calibration. Imaging of external complex scenes was carried out at low and high spectral resolution. These require full complex calibration to remove background contributions that vary dramatically over the instrument FOV. Testing is continuing to demonstrate the precise radiometric accuracy and noise characteristics.

Forward Genetic Dissection of Biofilm Development by Fusobacterium nucleatum: Novel Functions of Cell Division Proteins FtsX and EnvC.

PubMed

Wu, Chenggang; Al Mamun, Abu Amar Mohamed; Luong, Truc Thanh; Hu, Bo; Gu, Jianhua; Lee, Ju Huck; D'Amore, Melissa; Das, Asis; Ton-That, Hung

2018-04-24

Fusobacterium nucleatum is a key member of the human oral biofilm. It is also implicated in preterm birth and colorectal cancer. To facilitate basic studies of fusobacterial virulence, we describe here a versatile transposon mutagenesis procedure and a pilot screen for mutants defective in biofilm formation. Out of 10 independent biofilm-defective mutants isolated, the affected genes included the homologs of the Escherichia coli cell division proteins FtsX and EnvC, the electron transport protein RnfA, and four proteins with unknown functions. Next, a facile new gene deletion method demonstrated that nonpolar, in-frame deletion of ftsX or envC produces viable bacteria that are highly filamentous due to defective cell division. Transmission electron and cryo-electron microscopy revealed that the Δ ftsX and Δ envC mutant cells remain joined with apparent constriction, and scanning electron microscopy (EM) uncovered a smooth cell surface without the microfolds present in wild-type cells. FtsX and EnvC proteins interact with each other as well as a common set of interacting partners, many with unknown function. Last, biofilm development is altered when cell division is blocked by MinC overproduction; however, unlike the phenotypes of Δ ftsX and Δ envC mutants, a weakly adherent biofilm is formed, and the wild-type rugged cell surface is maintained. Therefore, FtsX and EnvC may perform novel functions in Fusobacterium cell biology. This is the first report of an unbiased approach to uncover genetic determinants of fusobacterial biofilm development. It points to an intriguing link among cytokinesis, cell surface dynamics, and biofilm formation, whose molecular underpinnings remain to be elucidated. IMPORTANCE Little is known about the virulence mechanisms and associated factors in F. nucleatum , due mainly to the lack of convenient genetic tools for this organism. We employed two efficient genetic strategies to identify F. nucleatum biofilm-defective mutants

New insights into FtsZ rearrangements during the cell division of Escherichia coli from single-molecule localization microscopy of fixed cells.

PubMed

Vedyaykin, Alexey D; Vishnyakov, Innokentii E; Polinovskaya, Vasilisa S; Khodorkovskii, Mikhail A; Sabantsev, Anton V

2016-06-01

FtsZ - a prokaryotic tubulin homolog - is one of the central components of bacterial division machinery. At the early stage of cytokinesis FtsZ forms the so-called Z-ring at mid-cell that guides septum formation. Many approaches were used to resolve the structure of the Z-ring, however, researchers are still far from consensus on this question. We utilized single-molecule localization microscopy (SMLM) in combination with immunofluorescence staining to visualize FtsZ in Esherichia coli fixed cells that were grown under slow and fast growth conditions. This approach allowed us to obtain images of FtsZ structures at different stages of cell division and accurately measure Z-ring dimensions. Analysis of these images demonstrated that Z-ring thickness increases during constriction, starting at about 70 nm at the beginning of division and increasing by approximately 25% half-way through constriction. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

An Essential Component in Chloroplast Development and Maintenance at Moderate High Temperature in Higher Plants: Chloroplast-targeted FtsH11 Proteases

USDA-ARS?s Scientific Manuscript database

Among the 12 predicted FtsH proteases in Arabidopsis, AtFtsH11 is the only metalloprotease targeting to both chloroplast and mitochondria and the only one essential for Arabidopsis plant to survive at moderate heat stress at all developmental stages. Under optimal conditions, atftsh11 mutants were...

Design, synthesis and evaluation of novel 2,5,6-trisubstituted benzimidazoles targeting FtsZ as antitubercular agents.

PubMed

Park, Bora; Awasthi, Divya; Chowdhury, Soumya R; Melief, Eduard H; Kumar, Kunal; Knudson, Susan E; Slayden, Richard A; Ojima, Iwao

2014-05-01

Filamenting temperature-sensitive protein Z (FtsZ), an essential cell division protein, is a promising target for the drug discovery of new-generation antibacterial agents against various bacterial pathogens. As a part of SAR studies on benzimidazoles, we have synthesized a library of 376 novel 2,5,6-trisubstituted benzimidazoles, bearing ether or thioether linkage at the 6-position. In a preliminary HTP screening against Mtb H37Rv, 108 compounds were identified as hits at a cut off concentration of 5 μg/mL. Among those hits, 10 compounds exhibited MIC values in the range of 0.63-12.5 μg/mL. Light scattering assay and TEM analysis with the most potent compound 5a clearly indicate that its molecular target is Mtb-FtsZ. Also, the Kd of 5a with Mtb-FtsZ was determined to be 1.32 μM. Copyright © 2014 Elsevier Ltd. All rights reserved.

New temperature and pressure retrieval algorithm for high-resolution infrared solar occultation spectroscopy: analysis and validation against ACE-FTS and COSMIC

NASA Astrophysics Data System (ADS)

Olsen, Kevin S.; Toon, Geoffrey C.; Boone, Chris D.; Strong, Kimberly

2016-03-01

Motivated by the initial selection of a high-resolution solar occultation Fourier transform spectrometer (FTS) to fly to Mars on the ExoMars Trace Gas Orbiter, we have been developing algorithms for retrieving volume mixing ratio vertical profiles of trace gases, the primary component of which is a new algorithm and software for retrieving vertical profiles of temperature and pressure from the spectra. In contrast to Earth-observing instruments, which can rely on accurate meteorological models, a priori information, and spacecraft position, Mars retrievals require a method with minimal reliance on such data. The temperature and pressure retrieval algorithms developed for this work were evaluated using Earth-observing spectra from the Atmospheric Chemistry Experiment (ACE) FTS, a solar occultation instrument in orbit since 2003, and the basis for the instrument selected for a Mars mission. ACE-FTS makes multiple measurements during an occultation, separated in altitude by 1.5-5 km, and we analyse 10 CO2 vibration-rotation bands at each altitude, each with a different usable altitude range. We describe the algorithms and present results of their application and their comparison to the ACE-FTS data products. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) provides vertical profiles of temperature up to 40 km with high vertical resolution. Using six satellites and GPS radio occultation, COSMIC's data product has excellent temporal and spatial coverage, allowing us to find coincident measurements with ACE with very tight criteria: less than 1.5 h and 150 km. We present an intercomparison of temperature profiles retrieved from ACE-FTS using our algorithm, that of the ACE Science Team (v3.5), and from COSMIC. When our retrievals are compared to ACE-FTS v3.5, we find mean differences between -5 and +2 K and that our retrieved profiles have no seasonal or zonal biases but do have a warm bias in the stratosphere and a cold bias in the

Submillimeter atmospheric FTS at the geographic South Pole

NASA Astrophysics Data System (ADS)

Chamberlin, Richard A.; Martin, Robert N.; Martin, Christopher L.; Stark, Antony A.

2003-02-01

A submillimeter Fourier Transform Spectrometer of the Martin-Puplett type was constructed and deployed to the geographical South Pole in 2001. The instrument operates from about 300 GHz to almost 2 THz and was used over winter to acquire atmospheric spectra with resolution as fine as 250 MHz. The main motivation for constructing and deploying this FTS was for astronomical site testing, but the obtained spectra can have important secondary uses in atmospheric science and transmission model validation. Some preliminary, low spectral resolution site testing results are presented here.

GP0.4 from bacteriophage T7: in silico characterisation of its structure and interaction with E. coli FtsZ.

PubMed

Simpkin, Adam J; Rigden, Daniel J

2016-07-13

Proteins produced by bacteriophages can have potent antimicrobial activity. The study of phage-host interactions can therefore inform small molecule drug discovery by revealing and characterising new drug targets. Here we characterise in silico the predicted interaction of gene protein 0.4 (GP0.4) from the Escherichia coli (E. coli) phage T7 with E. coli filamenting temperature-sensitive mutant Z division protein (FtsZ). FtsZ is a tubulin homolog which plays a key role in bacterial cell division and that has been proposed as a drug target. Using ab initio, fragment assembly structure modelling, we predicted the structure of GP0.4 with two programs. A structure similarity-based network was used to identify a U-shaped helix-turn-helix candidate fold as being favoured. ClusPro was used to dock this structure prediction to a homology model of E. coli FtsZ resulting in a favourable predicted interaction mode. Alternative docking methods supported the proposed mode which offered an immediate explanation for the anti-filamenting activity of GP0.4. Importantly, further strong support derived from a previously characterised insertion mutation, known to abolish GP0.4 activity, that is positioned in close proximity to the proposed GP0.4/FtsZ interface. The mode of interaction predicted by bioinformatics techniques strongly suggests a mechanism through which GP0.4 inhibits FtsZ and further establishes the latter's druggable intrafilament interface as a potential drug target.

Suppression of survivin expression in glioblastoma cells by the Ras inhibitor farnesylthiosalicylic acid promotes caspase-dependent apoptosis.

PubMed

Blum, Roy; Jacob-Hirsch, Jasmine; Rechavi, Gideon; Kloog, Yoel

2006-09-01

The Ras inhibitor farnesylthiosalicylic acid (FTS) has been shown to induce apoptosis in glioblastoma multiforme, but its mechanism of action was unknown. We show that FTS or dominant-negative Ras, by deregulating extracellular signal-regulated kinase and Akt signaling, decreases survivin gene transcripts in U87 glioblastoma multiforme, leading to disappearance of survivin protein and cell death. FTS affected both Ras-controlled regulators of survivin transcription and Ras-regulated survival signals. Thus, Ras inhibition by FTS resulted in release of the survivin "brake" on apoptosis and in activation of the mitochondrial apoptotic pathway: dephosphorylation of Bad, activation of Bax, release of cytochrome c, and caspase activation. FTS-induced apoptosis of U87 cells was strongly attenuated by forced expression of survivin or by caspase inhibitors. These results show that resistance to apoptosis in glioblastoma multiforme can be abolished by a single Ras inhibitor, which targets both survivin, a critical inhibitor of apoptosis, and the intrinsic mitochondrial apoptotic machinery.

ACE-FTS on SCISAT: 10th year on-orbit anniversary

NASA Astrophysics Data System (ADS)

Lachance, Richard L.; Buijs, Henry L.; Soucy, Marc-André

2013-09-01

The Atmospheric Chemistry Experiment (ACE) is a mission on-board the Canadian Space Agency's (CSA) SCISAT-1. ACE is composed of a suite of instruments consisting of an infrared Fourier Transform Spectrometer (FTS) coupled with an auxiliary imager monitoring aerosols based on the extinction of solar radiation using two filtered detectors (visible and near infrared). A suntracker is also included to provide fine pointing during occultation. A second instrument, MAESTRO, is a spectrophotometer covering the near ultra-violet to the near infrared. In combination, the instrument payload covers the spectral range from 0.25 to 13.3 μm. The ACE mission came about from a need to better understand the chemical and dynamical processes that control the distribution of ozone in the upper troposphere and stratosphere, with particular emphasis on the Arctic region. Measurement of the vertical distribution of molecular species in these portions of the atmosphere permits elucidation of the key chemical and dynamical processes. The ACE-FTS measures the vertical distributions of trace gases as well as polar stratospheric clouds, aerosols, and temperature by a solar occultation technique from low earth orbit. By measuring solar radiation at high spectral resolution as it passes through different layers of the atmosphere, the absorption thus measured provides information on vertical profiles of atmospheric constituents, temperature, and pressure. Detailed and sensitive vertical distribution of trace gases help to better understand the chemical processes not only for ozone formation and destruction but also for other dynamic processes in the atmosphere. The ACE/SCISAT-1 satellite was successfully launched by NASA on August 12, 2003, and has been successfully operating since, now celebrating its 10th year on-orbit anniversary. This paper presents a summary of the heritage and development history of the ACE-FTS instrument. Design challenges and solutions are related. The actual on

Hosting a Fourier Transform Spectrometer (FTS) on CubeSat Spacecraft Platforms for Global Measurements of Three-Dimensional Winds

NASA Astrophysics Data System (ADS)

Scott, D. K.; Neilsen, T. L.; Weston, C.; Frazier, C.; Smith, T.; Shumway, A.

2015-12-01

Global measurements of vertically-resolved atmospheric wind profiles offer the potential for improved weather forecasts and superior predictions of atmospheric wind patterns. A small-satellite constellation that uses a Fourier Transform Spectrometer (FTS) instrument onboard 12U CubeSats can provide measurements of global tropospheric wind profiles from space at a very low cost. These small satellites are called FTS CubeSats. This presentation will describe a spacecraft concept that provides a stable, robust platform to host the FTS payload. Of importance to the payload are power, data, station keeping, thermal, and accommodations that enable high spectral measurements to be made from a LEO orbit. The spacecraft concept draws on Space Dynamics Laboratory (SDL) heritage and the recent success of the Dynamic Ionosphere Cubesat Experiment (DICE) and HyperAngular Rainbow Polarimeter (HARP) missions. Working with team members, SDL built a prototype observatory (spacecraft and payload) for testing and proof of concept.

The Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) FTS: Results From the 2012/13 Alaska Campaigns

NASA Astrophysics Data System (ADS)

kurosu, T. P.; Miller, C. E.; Dinardo, S.

2013-12-01

The Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) is an aircraft-based Earth Venture 1 mission to study the carbon balance of the Alaskan Arctic ecosystem, with a particular focus on carbon release from melting permafrost. Operating from its base in Fairbanks, AK, the CARVE aircraft covers a range of principle flight paths in the Alaskan interior, the Yukon River valley, and northern Alaska coast around Barrow and Dead Horse. Flight paths are chosen to maximize ecosystem variability and and cover burn-recovery/regrowth sequences. CARVE observations cover the Arctic Spring/Summer/Fall seasons, with multiple flights per season and principle flight paths. Science operations started in 05/2012 and are currently envisaged to continue until 2015. The CARVE suite of instruments includes flask measurements and in situ gas analyzers for CO2, CH4 and CO observations, an active/passive L-band radar for surface conditions (freeze/thaw state), and a three-band polarizing Fourier Transform Spectrometer (FTS) for column measurements of CO2, CH4, CO, and interfering species (e.g., H2O). The FTS covers the spectral regions of 4,200-4,900 cm-1 (CH4, CO), 5,800-6,400 cm-1 (CO2), and 12,900-13,200 cm-1 (O2), with a spectral resolution of 0.2 cm-1. Aircraft-based FTS science observations in Alaska have been performed since 23-05-2012. First-version data products from all CARVE instruments derived from observations during the 2012 campaign were publicly released earlier in 2013. The FTS has performed well during flight conditions, particularly with respect to vibration damping. Outstanding challenges include the need for improved spectral and radiometric calibration, as well as compensating for low signal-to-noise spectra acquired under Alaskan flight conditions. We present results from FTS column observations of CO2, CH4, and CO, observed during the 2012 and 2013 campaigns, including preliminary comparisons of CARVE FTS measurements with satellite observations of CO2

Direct detection by real-time PCR of ftsI gene mutations affecting MICs of β-lactam agents for Haemophilus influenzae isolates from meningitis.

PubMed

Kishii, Kozue; Morozumi, Miyuki; Chiba, Naoko; Ono, Akiko; Ubukata, Kimiko

2011-10-01

One resistance mechanism of Haemophilus influenzae to ampicillin involves decreased affinity of penicillin-binding protein (PBP) 3 for β-lactam antibiotics reflecting amino acid substitutions in PBP3 encoded by the ftsI gene. Three amino acid substitutions, Ser385Thr, Arg517His, and Asn526Lys, are especially responsible for β-lactam resistance. We constructed a new real-time polymerase chain reaction (PCR) to directly detect these substitutions in addition to 16S ribosomal RNA (rRNA), cap, and bla(TEM) genes. Our real-time PCR was evaluated using 206 clinical H. influenzae strains isolated from pediatric patients with meningitis. Relative sensitivities and specificities of real-time PCR were 90.5-100% and 96.3-100% for all resistance classes compared with our previously reported conventional PCR. In addition, real-time PCR shortened time required from 3 h by conventional PCR to 1.5 h. When correlations between combinations of amino acid substitutions in the ftsI gene detected by real-time PCR and minimum inhibitory concentrations (MICs) of β-lactam antibiotics were evaluated, MIC(90)s of ampicillin for β-lactamase-nonproducing ampicillin-intermediate-resistant strains with Asn526Lys, β-lactamase-nonproducing, ampicillin-resistant strains with Ser385Thr, and β-lactamase-nonproducing ampicillin-resistant strains with both Asn526Lys and Ser385Thr, respectively, were two, four, and eight times higher than those for sensitive strains. Similarly, MIC(90)s of cephalosporins for these strains, respectively, were two, 16-32, and 16-32 times higher than those for sensitive strains. Thus, real-time PCR can guide antibiotic use.

Host regulation of lysogenic decision in bacteriophage lambda: transmembrane modulation of FtsH (HflB), the cII degrading protease, by HflKC (HflA).

PubMed

Kihara, A; Akiyama, Y; Ito, K

1997-05-27

The cII gene product of bacteriophage lambda is unstable and required for the establishment of lysogenization. Its intracellular amount is important for the decision between lytic growth and lysogenization. Two genetic loci of Escherichia coli are crucial for these commitments of infecting lambda genome. One of them, hflA encodes the HflKC membrane protein complex, which has been believed to be a protease degrading the cII protein. However, both its absence and overproduction stabilized cII in vivo and the proposed serine protease-like sequence motif in HflC was dispensable for the lysogenization control. Moreover, the HflKC protein was found to reside on the periplasmic side of the plasma membrane. In contrast, the other host gene, ftsH (hflB) encoding an integral membrane ATPase/protease, is positively required for degradation of cII, since loss of its function stabilized cII and its overexpression accelerated the cII degradation. In vitro, purified FtsH catalyzed ATP-dependent proteolysis of cII and HflKC antagonized the FtsH action. These results, together with our previous finding that FtsH and HflKC form a complex, suggest that FtsH is the cII degrading protease and HflKC is a modulator of the FtsH function. We propose that this transmembrane modulation differentiates the FtsH actions to different substrate proteins such as the membrane-bound SecY protein and the cytosolic cII protein. This study necessitates a revision of the prevailing view about the host control over lambda lysogenic decision.

Multi-layer Retrievals of Greenhouse Gases from a Combined Use of GOSAT TANSO-FTS SWIR and TIR

NASA Astrophysics Data System (ADS)

Kikuchi, N.; Kuze, A.; Kataoka, F.; Shiomi, K.; Hashimoto, M.; Suto, H.; Knuteson, R. O.; Iraci, L. T.; Yates, E. L.; Gore, W.; Tanaka, T.; Yokota, T.

2016-12-01

The TANSO-FTS sensor onboard GOSAT has three frequency bands in the shortwave infrared (SWIR) and the fourth band in the thermal infrared (TIR). Observations of high-resolution spectra of reflected sunlight in the SWIR are extensively utilized to retrieve column-averaged concentrations of the major greenhouse gases such as carbon dioxide (XCO2) and methane (XCH4). Although global XCO2 and XCH4 distribution retrieved from SWIR data can reduce the uncertainty in the current knowledge about sources and sinks of these gases, information on the vertical profiles would be more useful to constrain the surface flux and also to identify the local emission sources. Based on the degrees of freedom for signal, Kulawik et al. (2016, IWGGMS-12 presentation) shows that 2-layer information on the concentration of CO2 can be extracted from TANSO-FTS SWIR measurements, and the retrieval error is predicted to be about 5 ppm in the lower troposphere. In this study, we present multi-layer retrievals of CO2 and CH4 from a combined use of measurements of TANSO-FTS SWIR and TIR. We selected GOSAT observations at Railroad Valley Playa in Nevada, USA, which is a vicarious calibration site for TANSO-FTS, as we have various ancillary data including atmospheric temperature and humidity taken by a radiosonde, surface temperature, and surface emissivity with a ground based FTS. All of these data are useful especially for retrievals using TIR spectra. Currently, we use the 700-800 cm-1 and 1200-1300 cm-1 TIR windows for CO2 and CH4 retrievals, respectively, in addition to the SWIR bands. We found that by adding TIR windows, 3-layer information can be extracted, and the predicted retrieval error in the CO2 concentration was reduced about 1 ppm in the lower troposphere. We expect that the retrieval error could be further reduced by optimizing TIR windows and by reducing systematic forward model errors.

Phage ϕ29 protein p1 promotes replication by associating with the FtsZ ring of the divisome in Bacillus subtilis

PubMed Central

Ballesteros-Plaza, David; Holguera, Isabel; Scheffers, Dirk-Jan; Salas, Margarita; Muñoz-Espín, Daniel

2013-01-01

During evolution, viruses have optimized the interaction with host factors to increase the efficiency of fundamental processes such as DNA replication. Bacteriophage ϕ29 protein p1 is a membrane-associated protein that forms large protofilament sheets that resemble eukaryotic tubulin and bacterial filamenting temperature-sensitive mutant Z protein (FtsZ) polymers. In the absence of protein p1, phage ϕ29 DNA replication is impaired. Here we show that a functional fusion of protein p1 to YFP localizes at the medial region of Bacillus subtilis cells independently of other phage-encoded proteins. We also show that ϕ29 protein p1 colocalizes with the B. subtilis cell division protein FtsZ and provide evidence that FtsZ and protein p1 are associated. Importantly, the midcell localization of YFP-p1 was disrupted in a strain that does not express FtsZ, and the fluorescent signal was distributed all over the cell. Depletion of penicillin-binding protein 2B (PBP2B) in B. subtilis cells did not affect the subcellular localization of YFP-p1, indicating that its distribution does not depend on septal wall synthesis. Interestingly, when ϕ29 protein p1 was expressed, B. subtilis cells were about 1.5-fold longer than control cells, and the accumulation of ϕ29 DNA was higher in mutant B. subtilis cells with increased length. We discuss the biological role of p1 and FtsZ in the ϕ29 growth cycle. PMID:23836667

HVRM: a second generation ACE-FTS instrument concept

NASA Astrophysics Data System (ADS)

Lavigne, Jean-François; Larouche, Martin; Dupont, Fabien; Girard, Guillaume; Veilleux, James; Buijs, Henry; Desbiens, Raphaël.; Perron, Gaétan; Grandmont, Frédéric; Paradis, Simon; Moreau, Louis; Bourque, Hugo

2017-11-01

The Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) is the main instrument on-board the SCISAT-1 satellite, a mission mainly supported by the Canadian Space Agency [1]. It is in Low- Earth Orbit at an altitude of 650 km with an inclination of 74E. Its data has been used to track the vertical profile of more than 30 atmospheric species in the high troposphere and in the stratosphere with the main goal of providing crucial information for the comprehension of chemical and physical processes controlling the ozone life cycle. These atmospheric species are detected using high-resolution (0.02 cm-1) spectra in the 750-4400 cm-1 spectral region. This leads to more than 170 000 spectral channels being acquired in the IR every two seconds. It also measures aerosols and clouds to reduce the uncertainty in their effects on the global energy balance. It is currently the only instrument providing such in-orbit high resolution measurements of the atmospheric chemistry and is often used by international scientists as a unique data set for climate understanding. The satellite is in operation since 2003, exceeding its initially planned lifetime of 2 years by more than a factor of 5. Given its success, its usefulness and the uniqueness of the data it provides, the Canadian Space Agency has founded the development of technologies enabling the second generation of ACE-FTS instruments through the High Vertical Resolution Measurement (HVRM) project but is still waiting for the funding for a mission. This project addresses three major improvements over the ACE-FTS. The first one aims at improving the vertical instantaneous field-of-view (iFoV) from 4.0 km to 1.5 km without affecting the SNR and temporal precision. The second aims at providing precise knowledge on the tangent height of the limb observation from an external method instead of that used in SCISAT-1 where the altitude is typically inferred from the monotonic CO2 concentration seen in the spectra. The

Cell Division in genus Corynebacterium: protein-protein interaction and molecular docking of SepF and FtsZ in the understanding of cytokinesis in pathogenic species.

PubMed

Oliveira, Alberto F; Folador, Edson L; Gomide, Anne C P; Goes-Neto, Aristóteles; Azevedo, Vasco A C; Wattam, Alice R

2018-02-15

The genus Corynebacterium includes species of great importance in medical, veterinary and biotechnological fields. The genus-specific families (PLfams) from PATRIC have been used to observe conserved proteins associated to all species. Our results showed a large number of conserved proteins that are associated with the cellular division process. Was not observe in our results other proteins like FtsA and ZapA that interact with FtsZ. Our findings point that SepF overlaps the function of this proteins explored by molecular docking, protein-protein interaction and sequence analysis. Transcriptomic analysis showed that these two (Sepf and FtsZ) proteins can be expressed in different conditions together. The work presents novelties on molecules participating in the cell division event, from the interaction of FtsZ and SepF, as new therapeutic targets.

Multispectral analysis of Cygnus Loop and IC 443 with iFTS

NASA Astrophysics Data System (ADS)

Alarie, Alexandre

2016-06-01

Cygnus Loop and IC 443 are supernova remnants (SNRs) recognized as excellent laboratories to study the interaction between the SNR and the surrounding interstellar medium. The overall complex morphologies and large dimensions of those SNRs have always represented an observational challenge. This is especially true for optical observations for which the data available are very scarce. In order to palliate this scarcity in the optical regime, we are using two wide field-imaging Fourier transform spectrometers (iFTS): SpIOMM, attached to the Mont Megantic 1.6-m telescope and SITELLE recently installed at the Canada-France-Hawaii Telescope. Both instruments are capable of obtaining the spatially resolved visible spectrum of every source of light in an 11 arc minute field of view, in selected bandpasses. Using those iFTS on extended object such as Cygnus Loop and IC 443, we have obtained millions of spectra covering all major emission lines. Due to the large projected surface of Cygnus Loop and IC 443, we started a survey and the latest dataset will be presented. The extended 2D mappings of several emission lines ([O II] 3727, [O III] 4363, Hb, [O III] 4959, 5007, Ha, [N II] 6548, 6583 and [S II] 6716, 6731) allowed the creation of numerous ratios maps useful for shock diagnostics: shock velocity, electronic and temperature densities, location of incomplete shocks and extinction maps. These maps are then used to determine key parameters needed to compare the observations with theoretical shock models. Using the shock modeling code MAPPINGS, we can create abundances maps of nitrogen, oxygen and sulfur for an appreciable fraction of the observed regions. Furthermore, using the radial velocity as well as the spectro-imagery capability of the iFTS, we can have a glimpse of the three-dimensional structure of the remnants. All those data allow us to forge a coherent analysis of the complex interaction between the SNRs and their surrounding environment.

Examination about the Impact of Thin Clouds in IFOV of GOSAT TANSO-FTS on Estimates of XCO2 in the Amazon

NASA Astrophysics Data System (ADS)

Oishi, Y.; Kamei, A.; Murakami, K.; Dupuy, E.; Yokota, Y.; Hiraki, K.; Ninomiya, K.; Saito, M.; Yoshida, Y.; Morino, I.; Nakajima, T. Y.; Yokota, T.; Matsunaga, T.

2013-12-01

Greenhouse gases Observing SATellite (GOSAT) was launched in 2009 to measure the global atmospheric CO2 and CH4 concentrations. GOSAT is equipped with two sensors: the Thermal And Near-infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) and the Cloud and Aerosol Imager (TANSO-CAI). The presence of clouds in the instantaneous field-of-view (IFOV) of the FTS leads to incorrect estimates of the CO2 or CH4 concentration. To deal with this problem, the FTS data which are suspected to be cloud-contaminated must be identified and rejected. As a result, there are very few remaining FTS data in the region of tropical rainforest such as the Amazon. In the meanwhile the feasibility studies of GOSAT-2 started for more precise monitoring of atmospheric greenhouse gases than GOSAT in 2011. To improve the accuracy of estimates of the column-averaged dry air mole fraction of atmospheric CO2 (XCO2), we need to understand the present situation about cloud screening in the rain forest regions and to examine the cloud-contaminated data whose processing might be possible with improvement of instruments or algorithms. In this study we evaluated the impact of thin clouds on estimates of the XCO2 using an atmospheric radiative transfer code, which can simulate the spectrum at the top of the atmosphere under thin cloud conditions. First, we decided the input parameters, among which relative position of the sun and satellite to observation point, surface reflectance using cloud-free GOSAT data products in the Amazon, FTS L1B data products (radiance spectral data), FTS L2 data products (CO2 column abundance data), and CAI L3 data products (clear-sky reflectance data). The evaluation was performed by comparing depths of the CO2 absorption lines in output radiation spectra with varying CO2 concentrations and cloud conditions, cloud type, cloud optical depth, and cloud top altitude. We will present our latest results.

In Escherichia coli, MreB and FtsZ direct the synthesis of lateral cell wall via independent pathways that require PBP 2.

PubMed

Varma, Archana; Young, Kevin D

2009-06-01

In Escherichia coli, the cytoplasmic proteins MreB and FtsZ play crucial roles in ensuring that new muropeptide subunits are inserted into the cell wall in a spatially correct way during elongation and division. In particular, to retain a constant diameter and overall shape, new material must be inserted into the wall uniformly around the cell's perimeter. Current thinking is that MreB accomplishes this feat through intermediary proteins that tether peptidoglycan synthases to the outer face of the inner membrane. We tested this idea in E. coli by using a DD-carboxypeptidase mutant that accumulates pentapeptides in its peptidoglycan, allowing us to visualize new muropeptide incorporation. Surprisingly, inhibiting MreB with the antibiotic A22 did not result in uneven insertion of new wall, although the cells bulged and lost their rod shapes. Instead, uneven (clustered) incorporation occurred only if MreB and FtsZ were inactivated simultaneously, providing the first evidence in E. coli that FtsZ can direct murein incorporation into the lateral cell wall independently of MreB. Inhibiting penicillin binding protein 2 (PBP 2) alone produced the same clustered phenotype, implying that MreB and FtsZ tether peptidoglycan synthases via a common mechanism that includes PBP 2. However, cell shape was determined only by the presence or absence of MreB and not by the even distribution of new wall material as directed by FtsZ.

Intracellular crowding effects on the self-association of the bacterial cell division protein FtsZ.

PubMed

Naddaf, Lamis; Sayyed-Ahmad, Abdallah

2014-12-15

The dimerization rate of the bacterial cell division protein FtsZ is strongly affected by the intracellular crowding. Yet the complexity of the intracellular environment makes it difficult to investigate via all-atom molecular dynamics or other detailed theoretical methods. We study the crowding effect on FtsZ dimerization which is the first step of an oligomerization process that results in more elaborate supramolecular structures. In particular, we consider the effect of intracellular crowding on the reaction rates, and their dependence on the different concentrations of crowding agents. We achieved this goal by using Brownian dynamics (BD) simulation techniques and a modified post-processing approach in which we decompose the rate constant in crowded media as a product of the rate constant in the dilute solution times a factor that incorporates the crowding effect. The latter factor accounts for the diffusion reduction and crowder induced energy. In addition we include the crowding effects on water viscosity in the BD simulations of crowded media. We finally show that biomolecular crowding has a considerable effect on the FtsZ dimerization by increasing the dimerization rate constant from 2.6×10(7)M(-1)s(-1) in the absence of crowders to 1.0×10(8)M(-1)s(-1) at crowding level of 0.30. Copyright © 2014 Elsevier Inc. All rights reserved.

GOSAT TIR spectral validation with High/Low temperature target using Aircraft base-FTS S-HIS

NASA Astrophysics Data System (ADS)

Kataoka, F.; Knuteson, R.; Taylor, J. K.; Kuze, A.; Shiomi, K.; Suto, H.; Yoshida, J.

2017-12-01

The Greenhouse gases Observing SATellite (GOSAT) was launched on January 2009. The GOSAT is equipped with TANSO-FTS (Fourier-Transform Spectrometer), which observe reflected solar radiation from the Earth's surface with shortwave infrared (SWIR) band and thermal emission from the Earth's surface and atmosphere with thermal infrared (TIR) band. The TIR band cover wide spectral range (650 - 1800 [cm-1]) with a high spectral resolution (0.2 [cm-1]). The TIR spectral information provide vertical distribution of CO2 and CH4. GOSAT has been operation more than eight years. In this long operation, GOSAT had experienced two big accidents; Rotation of one of the solar paddles stopped and sudden TANSO-FTS operation stop in May 2014 and cryocooler shutdown and restart in August - September 2015. These events affected the operation condition of the TIR photo-conductive (PC)-MCT detector. FTS technology using multiplex wide spectra needs wide dynamic range. PC detector has nonlinearity. Its correction needs accurate estimation of time-dependent offset. In current TIR Level 1B product version (V201), the non-photon level offset (Vdc_offset) estimated from on-orbit deep space calibration data and pre-launch background radiation model. But the background radiation and detector temperature have changed after cryocooler shutdown events. These changes are too small to detect from onboard temperature sensors. The next TIR Level 1B product uses cross calibration data together with deep space calibration data and instrument radiation model has been updated. This work describes the evaluation of new TIR Level 1B spectral quality with aircraft-based FTS; Scanning High-resolution Interferometer Sounder (S-HIS). The S-HIS mounted on the high-altitude ER-2 aircraft and flew at about 20km altitude. Because the observation geometry of GOSAT and S-HIS are quite different, we used the double difference method using atmospheric transfer model. GOSAT TIR band cover wide dynamic range, so we check

Dynamic morphologies of pollen plastids visualised by vegetative-specific FtsZ1-GFP in Arabidopsis thaliana.

PubMed

Fujiwara, Makoto T; Hashimoto, Haruki; Kazama, Yusuke; Hirano, Tomonari; Yoshioka, Yasushi; Aoki, Seishiro; Sato, Naoki; Itoh, Ryuuichi D; Abe, Tomoko

2010-06-01

The behaviour and multiplication of pollen plastids have remained elusive despite their crucial involvement in cytoplasmic inheritance. Here, we present live images of plastids in pollen grains and growing tubes from transgenic Arabidopsis thaliana lines expressing stroma-localised FtsZ1-green-fluorescent protein fusion in a vegetative cell-specific manner. Vegetative cells in mature pollen contained a morphologically heterogeneous population of round to ellipsoidal plastids, whilst those in late-developing (maturing) pollen included plastids that could have one or two constriction sites. Furthermore, plastids in pollen tubes exhibited remarkable tubulation, stromule (stroma-filled tubule) extension, and back-and-forth movement along the direction of tube growth. Plastid division, which involves the FtsZ1 ring, was rarely observed in mature pollen grains.

Do the same traffic rules apply? Directional chromosome segregation by SpoIIIE and FtsK.

PubMed

Besprozvannaya, Marina; Burton, Briana M

2014-08-01

Over a decade of studies have tackled the question of how FtsK/SpoIIIE translocases establish and maintain directional DNA translocation during chromosome segregation in bacteria. FtsK/SpoIIIE translocases move DNA in a highly processive, directional manner, where directionality is facilitated by sequences on the substrate DNA molecules that are being transported. In recent years, structural, biochemical, single-molecule and high-resolution microscopic studies have provided new insight into the mechanistic details of directional DNA segregation. Out of this body of work, a series of models have emerged and, ultimately, yielded two seemingly opposing models: the loading model and the target search model. We review these recent mechanistic insights into directional DNA movement and discuss the data that may serve to unite these suggested models, as well as propose future directions that may ultimately solve the debate. © 2014 John Wiley & Sons Ltd.

YeeU enhances the bundling of cytoskeletal polymers of MreB and FtsZ, antagonizing the CbtA (YeeV) toxicity in Escherichia coli.

PubMed

Masuda, Hisako; Tan, Qian; Awano, Naoki; Wu, Kuen-Phon; Inouye, Masayori

2012-06-01

All free-living bacteria carry the toxin-antitoxin (TA) systems controlling cell growth and death under stress conditions. YeeU-YeeV (CbtA) is one of the Escherichia coli TA systems, and the toxin, CbtA, has been reported to inhibit the polymerization of bacterial cytoskeletal proteins, MreB and FtsZ. Here, we demonstrate that the antitoxin, YeeU, is a novel type of antitoxin (type IV TA system), which does not form a complex with CbtA but functions as an antagonist for CbtA toxicity. Specifically, YeeU was found to directly interact with MreB and FtsZ, and enhance the bundling of their filamentous polymers in vitro. Surprisingly, YeeU neutralized not only the toxicity of CbtA but also the toxicity caused by other inhibitors of MreB and FtsZ, such as A22, SulA and MinC, indicating that YeeU-induced bundling of MreB and FtsZ has an intrinsic global stabilizing effect on their homeostasis. Here we propose to rename YeeU as CbeA for cytoskeleton bundling-enhancing factor A. © 2012 Blackwell Publishing Ltd.

Escherichia coli FtsH (HflB) degrades a membrane-associated TolAI-II-beta-lactamase fusion protein under highly denaturing conditions.

PubMed

Cooper, K W; Baneyx, F

2001-03-01

TolAI--II--beta-lactamase, a fusion protein consisting of the inner membrane and transperiplasmic domains of TolA followed by TEM--beta-lactamase associated with the inner membrane but remained confined to the cytoplasm when expressed at high level in Escherichia coli. Although the fusion protein was resistant to proteolysis in vivo, it was hydrolyzed during preparative SDS-polyacrylamide electrophoresis and when insoluble cellular fractions unfolded with 5 M urea were subjected to microdialysis. Inhibitor profiling studies revealed that both a metallo- and serine protease were involved in TolAI--II--beta-lactamase degradation under denaturing conditions. The in vitro degradation rates of the fusion protein were not affected when insoluble fractions were harvested from a strain lacking protease IV, but were significantly reduced when microdialysis experiments were conducted with material isolated from an isogenic ftsH1 mutant. Adenine nucleotides were not required for degradation, and ATP supplementation did not accelerate the apparent rate of TolAI--II--beta-lactamase hydrolysis under denaturing conditions. Our results indicate that the metalloprotease active site of FtsH remains functional in the presence of 3--5 M urea and suggest that the ATPase and proteolytic activities of FtsH can be uncoupled if the substrate is sufficiently unstructured. Thus, a key role of the FtsH AAA module appears to be the net unfolding of bound substrates so that they can be efficiently engaged by the protease active site. Copyright 2001 Academic Press.

Plastidial NAD-Dependent Malate Dehydrogenase: A Moonlighting Protein Involved in Early Chloroplast Development Through its Interaction with an FtsH12-FtsHi Protease Complex.

PubMed

Schreier, Tina B; Antoine, Cléry; Schläfli, Michael; Galbier, Florian; Stadler, Martha; Demarsy, Emilie; Albertini, Daniele; Maier, Benjamin A; Kessler, Felix; Hörtensteiner, Stefan; Zeeman, Samuel C; Kötting, Oliver

2018-06-22

Malate dehydrogenases (MDH) convert malate to oxaloacetate using NAD(H) or NADP(H) as a cofactor. Arabidopsis thaliana mutants lacking plastidial NAD-dependent MDH (pdnad-mdh) are embryo-lethal, and constitutive silencing (miR-mdh-1) causes a pale, dwarfed phenotype. The reason for these severe phenotypes is unknown. Here, we rescued the embryo lethality of pdnad-mdh via embryo-specific expression of pdNAD-MDH. Rescued seedlings developed white leaves with aberrant chloroplasts and failed to reproduce. Inducible silencing of pdNAD-MDH at the rosette stage also resulted in white newly emerging leaves. These data suggest that pdNAD-MDH is important for early plastid development, which is consistent with the reductions in major plastidial galactolipid, carotenoid and protochlorophyllide levels in miR-mdh-1 seedlings. Surprisingly, the targeting of other NAD-dependent MDH isoforms to the plastid did not complement the embryo lethality of pdnad-mdh, while expression of enzymatically inactive pdNAD-MDH did. These complemented plants grew indistinguishably from the wild type. Both active and inactive forms of pdNAD-MDH interact with a heteromeric AAA-ATPase complex at the inner membrane of the chloroplast envelope. Silencing the expression of FtsH12, a key member of this complex, resulted in a phenotype that strongly resembles miR-mdh-1. We propose that pdNAD-MDH is essential for chloroplast development due to its moonlighting role in stabilizing FtsH12, distinct from its enzymatic function. © 2018 American Society of Plant Biologists. All rights reserved.

Remote sensing of GHG over Paris megacity and Orléans forest using ground-based QualAir FTS and TCCON-Orléans

NASA Astrophysics Data System (ADS)

Te, Y.; Jeseck, P.; Da Costa, J.; Deutscher, N. M.; Warneke, T.; Notholt, J.

2012-04-01

In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants are increasing continuously. Monitoring and control of atmospheric pollutants in megacities have become a major challenge for scientists and public health authorities in environmental research area. The QualAir platform at University Pierre et Marie Curie (UPMC), is an innovating experimental research platform dedicated to survey greenhouse gases (GHGs) and urban air quality. As one of the major instruments of the QualAir platform, the ground-based Fourier transform spectrometer (QualAir FTS, IFS 125HR model) analyses the composition of the urban atmosphere of Paris, which is the third European megacity. The continuous monitoring of atmospheric pollutants is essential to improve the understanding of urban air pollution processes. Associated with a sun-tracker, the QualAir remote sensing FTS operates in solar infrared absorption and enables to monitor many trace gases, and to follow up their variability in the Ile-de-France region. A description of the QualAir FTS will be given. Concentrations of atmospheric GHG, especially CO2 and CH4, are retrieved by the radiative transfer model PROFFIT. Located in the centre of Paris, the QualAir FTS can provide new and complementary urban measurements as compared to unpolluted ground-based stations of existing networks (NDACC and TCCON). The work made by LPMAA to join the TCCON network will also be presented. TCCON-Orléans is a ground-based FTS of the TCCON network located in the forest of Orléans (100 km south of Paris). Preliminary comparisons of GHGs measurements from both sites will be shown. Such ground-based information will help to better characterize regional GHGs, especially regarding anthropogenic emissions and trends.

Prediction of Safety Stock Using Fuzzy Time Series (FTS) and Technology of Radio Frequency Identification (RFID) for Stock Control at Vendor Managed Inventory (VMI)

NASA Astrophysics Data System (ADS)

Mashuri, Chamdan; Suryono; Suseno, Jatmiko Endro

2018-02-01

This research was conducted by prediction of safety stock using Fuzzy Time Series (FTS) and technology of Radio Frequency Identification (RFID) for stock control at Vendor Managed Inventory (VMI). Well-controlled stock influenced company revenue and minimized cost. It discussed about information system of safety stock prediction developed through programming language of PHP. Input data consisted of demand got from automatic, online and real time acquisition using technology of RFID, then, sent to server and stored at online database. Furthermore, data of acquisition result was predicted by using algorithm of FTS applying universe of discourse defining and fuzzy sets determination. Fuzzy set result was continued to division process of universe of discourse in order to be to final step. Prediction result was displayed at information system dashboard developed. By using 60 data from demand data, prediction score was 450.331 and safety stock was 135.535. Prediction result was done by error deviation validation using Mean Square Percent Error of 15%. It proved that FTS was good enough in predicting demand and safety stock for stock control. For deeper analysis, researchers used data of demand and universe of discourse U varying at FTS to get various result based on test data used.

Electrostatic Evaluation of the ARES I FTS Antenna Materials

NASA Technical Reports Server (NTRS)

Hogue, Michael D.; Calle, Carlos I.

2010-01-01

Surface resistivity and volume resistivity data show all the tested non-metallic materials of the Ares I FTS antenna assembly to be insulative. The external materials (White foam, phenolic) should be able to develop a large surface charge density upon tribocharging with ice crystal impingement. Dielectric breakdown tests on the FTS antenna housing materials show that each of the insulative materials are very resistive to electrical breakdown. The thicknesses of these materials in a nominal housing should protect the antenna from direct breakdown from external triboelectric charging potentials. Per data from the Air Force study, a maximum external electric potential in the range of 100kV can be developed on surfaces tribocharged by ice crystal impingement. Testing showed that under operational pressure ranges, this level of exterior voltage can result in a potential of about 6 kV induced on the electrically floating interior antenna vanes. Testing the vanes up to this voltage level showed that electrostatic discharges can occur between the electrically floating vanes and the center, grounded screw heads. Repeated tests with multiple invisible and visible discharges caused only superficial physical damage to the vanes. Fourier analysis of the discharge signals showed that the frequency range of credible discharges would not interfere with the nominal operation of the FTS antenna. However, due to the limited scope, short timetable, and limited funding of this study, a direct measurement of the triboelectric charge that could be generated on the Ares I antenna housing when the rocket traverses an ice cloud at supersonic speeds was not performed. Instead, data for the limited Air Force study [3] was used as input for our experiments. The Air Force data used was not collected with a sensor located to provide us with the best approximation at the geometry of the Ares I rocket, namely that of the windshield electrometer, because brush discharges to the metal frame of the

One-year operation of TANSO-FTS on GOSAT and follow-on mission feasibility

NASA Astrophysics Data System (ADS)

Shiomi, Kei; Nakajima, Masakatsu; Kuze, Akihiko; Takeshima, Toshiaki; Kawakami, Shuji; Suto, Hiroshi

2017-11-01

The Greenhouse gases Observing SATellite (GOSAT) was developed to contribute to monitoring of carbon dioxide and methane from space [1]. The mission objectives are global greenhouse gas measurements from space with precision of 1 % for CO2 and 2 % for CH4 in seasonal mean. The GOSAT carries Thermal And Near infrared Sensor for carbon Observation (TANSO) for precise measurement of greenhouse gases. Main instrument is Fourier Transfer Spectrometer (TANSO-FTS) to observe atmospheric absorption spectra of CO2 and CH4 with high spectral resolution of 0.2 cm-1, broad wavelength coverage of 0.76 - 14.3 microns, wide swath of 790 km and frequent revisit of 3 days. Cloud and Aerosol Imager (TANSO-CAI) is simultaneously on board for cloud detection and correction of optical thin cirrus and aerosol interference within the FTS instantaneous field of view. The GOSAT satellite was launched by H2A-15 rocket on January 23, 2009. The Level 1B products of calibrated spectra were released from September 2009 in public. The Level 2 products of CO2 and CH4 column densities were released from February 2010 [2]. The normal observation data is acquired over one year regularly from April 2009. The mission lifetime is 5 years.

Testing of FTS fingers and interface using a passive compliant robot manipulator. [flight telerobot servicer

NASA Technical Reports Server (NTRS)

Nguyen, Charles C.; Antrazi, Sami S.

1992-01-01

This report deals with testing of a pair of robot fingers designed for the Flight Telerobotic Servicer (FTS) to grasp a cylinder type of Orbital Replaceable Unit (ORU) interface. The report first describes the objectives of the study and then the testbed consisting of a Stewart Platform-based manipulator equipped with a passive compliant platform which also serves as a force/torque sensor. Kinematic analysis is then performed to provide a closed-form solution for the force inverse kinematics and iterative solution for the force forward kinematics using the Newton's Raphson Method. Mathematical expressions are then derived to compute force/torques applied to the FTS fingers during the mating/demating with the interface. The report then presents the three parts of the experimental study on the feasibility and characteristics of the fingers. The first part obtains data of forces applied by the fingers to the interface under various misalignments, the second part determines the maximum allowable capture angles for mating, and the third part processes and interprets the obtained force/torque data.

An Improved Small-Molecule Inhibitor of FtsZ with Superior In Vitro Potency, Drug-Like Properties, and In Vivo Efficacy

PubMed Central

Baker, Nicola; Bennett, James M.; Berry, Joanne; Collins, Ian; Czaplewski, Lloyd G.; Logan, Alastair; Macdonald, Rebecca; MacLeod, Leanne; Peasley, Hilary; Mitchell, Jeffrey P.; Nayal, Narendra; Yadav, Anju; Srivastava, Anil; Haydon, David J.

2013-01-01

The bacterial cell division protein FtsZ is an attractive target for small-molecule antibacterial drug discovery. Derivatives of 3-methoxybenzamide, including compound PC190723, have been reported to be potent and selective antistaphylococcal agents which exert their effects through the disruption of intracellular FtsZ function. Here, we report the further optimization of 3-methoxybenzamide derivatives towards a drug candidate. The in vitro and in vivo characterization of a more advanced lead compound, designated compound 1, is described. Compound 1 was potently antibacterial, with an average MIC of 0.12 μg/ml against all staphylococcal species, including methicillin- and multidrug-resistant Staphylococcus aureus and Staphylococcus epidermidis. Compound 1 inhibited an S. aureus strain carrying the G196A mutation in FtsZ, which confers resistance to PC190723. Like PC190723, compound 1 acted on whole bacterial cells by blocking cytokinesis. No interactions between compound 1 and a diverse panel of antibiotics were measured in checkerboard experiments. Compound 1 displayed suitable in vitro pharmaceutical properties and a favorable in vivo pharmacokinetic profile following intravenous and oral administration, with a calculated bioavailability of 82.0% in mice. Compound 1 demonstrated efficacy in a murine model of systemic S. aureus infection and caused a significant decrease in the bacterial load in the thigh infection model. A greater reduction in the number of S. aureus cells recovered from infected thighs, equivalent to 3.68 log units, than in those recovered from controls was achieved using a succinate prodrug of compound 1, which was designated compound 2. In summary, optimized derivatives of 3-methoxybenzamide may yield a first-in-class FtsZ inhibitor for the treatment of antibiotic-resistant staphylococcal infections. PMID:23114779

Assessing stratospheric transport in the CMAM30 simulations using ACE-FTS measurements

NASA Astrophysics Data System (ADS)

Kolonjari, Felicia; Plummer, David A.; Walker, Kaley A.; Boone, Chris D.; Elkins, James W.; Hegglin, Michaela I.; Manney, Gloria L.; Moore, Fred L.; Pendlebury, Diane; Ray, Eric A.; Rosenlof, Karen H.; Stiller, Gabriele P.

2018-05-01

Stratospheric transport in global circulation models and chemistry-climate models is an important component in simulating the recovery of the ozone layer as well as changes in the climate system. The Brewer-Dobson circulation is not well constrained by observations and further investigation is required to resolve uncertainties related to the mechanisms driving the circulation. This study has assessed the specified dynamics mode of the Canadian Middle Atmosphere Model (CMAM30) by comparing to the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) profile measurements of CFC-11 (CCl3F), CFC-12 (CCl2F2), and N2O. In the CMAM30 specified dynamics simulation, the meteorological fields are nudged using the ERA-Interim reanalysis and a specified tracer was employed for each species, with hemispherically defined surface measurements used as the boundary condition. A comprehensive sampling technique along the line of sight of the ACE-FTS measurements has been utilized to allow for direct comparisons between the simulated and measured tracer concentrations. The model consistently overpredicts tracer concentrations of CFC-11, CFC-12, and N2O in the lower stratosphere, particularly in the northern hemispheric winter and spring seasons. The three mixing barriers investigated, including the polar vortex, the extratropical tropopause, and the tropical pipe, show that there are significant inconsistencies between the measurements and the simulations. In particular, the CMAM30 simulation underpredicts mixing efficiency in the tropical lower stratosphere during the June-July-August season.

Detectability and anatomical correlation of middle ear cholesteatoma using fused thin slice non-echo planar imaging diffusion-weighted image and magnetic resonance cisternography (FTS-nEPID).

PubMed

Kanoto, Masafumi; Sugai, Yukio; Hosoya, Takaaki; Toyoguchi, Yuuki; Konno, Yoshihiro; Watarai, Fumika; Ito, Tsukasa; Watanabe, Tomoo; Kakehata, Seiji

2015-12-01

Cholesteatomas show high intensity in diffusion-weighted imaging (DWI). We performed fused thin slice non-echo planar imaging (EPI) DWI and magnetic resonance cisternography (FTS-nEPID) for cholesteatoma patients to increase the detectability of FTS-nEPID for cholesteatoma. The subjects are 77 consecutive patients who underwent FTS-nEPID as a preoperative study (mean age: 53.3±21.8, 47 men and 30 women). Otorhinolaryngologists performed the operations. We anatomically classified the middle ear into four portions. A radiologist evaluated the images for cholesteatoma and assessed the anatomical invasive range in four portions using only FTS-nEPID. We classified large cholesteatomas that invaded more than three portions and small ones that invaded less than two portions based on the results obtained from surgery, and calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). For all cholesteatomas with an existing diagnosis, the sensitivity, specificity, PPV, and NPV were 71%, 70%, 94%, and 27%, respectively. In anatomical evaluation, the sensitivity, specificity, PPV, and NPV were 49%, 85%, 77%, and 64%, respectively. For large cholesteatomas with an existing diagnosis, the sensitivity was 86%. In anatomical evaluation, the sensitivity, specificity, PPV, and NPV were 51%, 57%, 88%, and 18%, respectively. For small cholesteatomas with an existing diagnosis, the sensitivity, specificity, PPV, and NPV were 59%, 78%, 92%, and 30%, respectively. In anatomical evaluation, the sensitivity, specificity, PPV, and NPV were 40%, 85%, 60%, and 71%, respectively. FTS-nEPID may be useful for diagnosing cholesteatomas. Further research is needed for anatomical evaluation because there were many false-negative results. Copyright © 2015 Elsevier Inc. All rights reserved.

VizieR Online Data Catalog: FTS reference UV wavelengths of CrIII (Smillie+, 2008)

NASA Astrophysics Data System (ADS)

Smillie, D. G.; Pickering, J. C.; Smith, P. L.

2009-03-01

The Cr III spectrum was acquired in the wavenumber range 31596 to 63192cm-1, using the Imperial College (IC) VUV FTS, and a PDL as light source. The spectral resolution used, 0.12cm-1, was sufficient to fully resolve the Doppler broadened transition line profiles, for which the average unblended full-width at half maximum (FWHM) was just under 0.3cm-1. (1 data file).

In vivo structure of the E. coli FtsZ-ring revealed by photoactivated localization microscopy (PALM).

PubMed

Fu, Guo; Huang, Tao; Buss, Jackson; Coltharp, Carla; Hensel, Zach; Xiao, Jie

2010-09-13

The FtsZ protein, a tubulin-like GTPase, plays a pivotal role in prokaryotic cell division. In vivo it localizes to the midcell and assembles into a ring-like structure-the Z-ring. The Z-ring serves as an essential scaffold to recruit all other division proteins and generates contractile force for cytokinesis, but its supramolecular structure remains unknown. Electron microscopy (EM) has been unsuccessful in detecting the Z-ring due to the dense cytoplasm of bacterial cells, and conventional fluorescence light microscopy (FLM) has only provided images with limited spatial resolution (200-300 nm) due to the diffraction of light. Hence, given the small sizes of bacteria cells, identifying the in vivo structure of the Z-ring presents a substantial challenge. Here, we used photoactivated localization microscopy (PALM), a single molecule-based super-resolution imaging technique, to characterize the in vivo structure of the Z-ring in E. coli. We achieved a spatial resolution of ∼35 nm and discovered that in addition to the expected ring-like conformation, the Z-ring of E. coli adopts a novel compressed helical conformation with variable helical length and pitch. We measured the thickness of the Z-ring to be ∼110 nm and the packing density of FtsZ molecules inside the Z-ring to be greater than what is expected for a single-layered flat ribbon configuration. Our results strongly suggest that the Z-ring is composed of a loose bundle of FtsZ protofilaments that randomly overlap with each other in both longitudinal and radial directions of the cell. Our results provide significant insight into the spatial organization of the Z-ring and open the door for further investigations of structure-function relationships and cell cycle-dependent regulation of the Z-ring.

ACE-FTS and MIPAS observations of phosgene (COCl2) and comparisons with SLIMCAT chemical transport model calculations

NASA Astrophysics Data System (ADS)

Harrison, Jeremy; Chipperfield, Martyn; Moore, David; Boone, Christopher; Bernath, Peter; Hossaini, Ryan

2017-04-01

The majority of chlorine in the atmosphere has arisen from anthropogenic emissions of 'organic' species such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). Due to their long lifetimes, many of these species reach the stratosphere where they break down, liberating chlorine which catalyses the destruction of ozone. The principal degradation products of Cl-containing organic species are carbonyl chloride (phosgene, COCl2), carbonyl chloride fluoride (COClF), and hydrogen chloride (HCl). Of these, phosgene is probably the most notorious, having been used as a chemical weapon in World War I. In the lower stratosphere, where the phosgene mixing ratios peak, the principal sources are the photolysis of carbon tetrachloride (CCl4) and, to a lesser extent, methyl chloroform (CH3CCl3). Smaller contributions arise from very short-lived substances such as CH2Cl2, CHCl3 and C2Cl4. Due to the success of the Montreal Protocol in phasing out the use of CCl4 and CH3CCl3, the abundance of phosgene continues to fall. Observing and understanding phosgene in the stratosphere helps us better understand the chlorine budget, and particularly the atmospheric removal of CCl4, which has attracted particular interest recently on account of the inconsistency between observations of its abundance and estimated sources and sinks. This work presents global distributions and trends of COCl2 using data from two satellite limb instruments: the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS), and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). The ACE-FTS instrument, on board the SCISAT satellite, has been recording solar occultation spectra through the Earth's atmosphere since 2004 and continues to take measurements with only minor loss in performance. ACE-FTS time series are available for a range of chlorine 'source' gases, including CCl3F (CFC-11), CCl2F2 (CFC-12), CHF2Cl (HCFC-22) and CCl4, and the chlorine 'product' gases COCl2

Hybrids from Farnesylthiosalicylic Acid and Hydroxamic Acid as Dual Ras-Related Signaling and Histone Deacetylase (HDAC) Inhibitors: Design, Synthesis and Biological Evaluation.

PubMed

Ling, Yong; Wang, Xuemin; Wang, Chenniu; Xu, Chenjun; Zhang, Wei; Zhang, Yihua; Zhang, Yanan

2015-06-01

A novel series of hybrids was designed and synthesized by combining key elements from farnesylthiosalicylic acid (FTS) and hydroxamic acid. Several 3,7,11-trimethyldodeca-2,6,10-trien-1-yl) thio)benzamide derivatives, particularly those with branched and linear aliphatic linkers between the hydroxamic zinc binding group (ZBG) and the benzamide core, not only displayed significant antitumor activities against six human cancer cells but also exhibited histone deacetylase (HDAC) inhibitory effects in vitro. Among them, N-(4-(hydroxyamino)-4-oxobutyl)-2-(((2E,6E)-3,7,11-trimethyldodeca-2,6, 10-trien-1-yl)thio)benzamide (8 d) was the most potent, with IC50 values of 4.9-7.6 μM; these activities are eight- to sixteen-fold more potent than FTS and comparable to that of suberoylanilide hydroxamic acid (SAHA). Derivative 8 d induced cell cycle arrest in the G0/G1 phase, inhibited the acetylation of histone H3 and α-tubulin, and blocked Ras-related signaling pathways in a dose-dependent manner. The improved tumor growth inhibition and cell-cycle arrest in vitro might result from the dual inhibition. These findings suggest dual inhibitors of Ras-related signaling pathway and HDAC hold promise as therapeutic agents for the treatment of cancer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cytoplasmic Domain of MscS Interacts with Cell Division Protein FtsZ: A Possible Non-Channel Function of the Mechanosensitive Channel in Escherichia Coli.

PubMed

Koprowski, Piotr; Grajkowski, Wojciech; Balcerzak, Marcin; Filipiuk, Iwona; Fabczak, Hanna; Kubalski, Andrzej

2015-01-01

Bacterial mechano-sensitive (MS) channels reside in the inner membrane and are considered to act as emergency valves whose role is to lower cell turgor when bacteria enter hypo-osmotic environments. However, there is emerging evidence that members of the Mechano-sensitive channel Small (MscS) family play additional roles in bacterial and plant cell physiology. MscS has a large cytoplasmic C-terminal region that changes its shape upon activation and inactivation of the channel. Our pull-down and co-sedimentation assays show that this domain interacts with FtsZ, a bacterial tubulin-like protein. We identify point mutations in the MscS C-terminal domain that reduce binding to FtsZ and show that bacteria expressing these mutants are compromised in growth on sublethal concentrations of β-lactam antibiotics. Our results suggest that interaction between MscS and FtsZ could occur upon inactivation and/or opening of the channel and could be important for the bacterial cell response against sustained stress upon stationary phase and in the presence of β-lactam antibiotics.

Cytoplasmic Domain of MscS Interacts with Cell Division Protein FtsZ: A Possible Non-Channel Function of the Mechanosensitive Channel in Escherichia Coli

PubMed Central

Koprowski, Piotr; Grajkowski, Wojciech; Balcerzak, Marcin; Filipiuk, Iwona; Fabczak, Hanna; Kubalski, Andrzej

2015-01-01

Bacterial mechano-sensitive (MS) channels reside in the inner membrane and are considered to act as emergency valves whose role is to lower cell turgor when bacteria enter hypo-osmotic environments. However, there is emerging evidence that members of the Mechano-sensitive channel Small (MscS) family play additional roles in bacterial and plant cell physiology. MscS has a large cytoplasmic C-terminal region that changes its shape upon activation and inactivation of the channel. Our pull-down and co-sedimentation assays show that this domain interacts with FtsZ, a bacterial tubulin-like protein. We identify point mutations in the MscS C-terminal domain that reduce binding to FtsZ and show that bacteria expressing these mutants are compromised in growth on sublethal concentrations of β-lactam antibiotics. Our results suggest that interaction between MscS and FtsZ could occur upon inactivation and/or opening of the channel and could be important for the bacterial cell response against sustained stress upon stationary phase and in the presence of β-lactam antibiotics. PMID:25996836

ZapE Is a Novel Cell Division Protein Interacting with FtsZ and Modulating the Z-Ring Dynamics

PubMed Central

Marteyn, Benoit S.; Karimova, Gouzel; Fenton, Andrew K.; Gazi, Anastasia D.; West, Nicholas; Touqui, Lhousseine; Prevost, Marie-Christine; Betton, Jean-Michel; Poyraz, Oemer; Ladant, Daniel; Gerdes, Kenn; Sansonetti, Philippe J.; Tang, Christoph M.

2014-01-01

ABSTRACT Bacterial cell division requires the formation of a mature divisome complex positioned at the midcell. The localization of the divisome complex is determined by the correct positioning, assembly, and constriction of the FtsZ ring (Z-ring). Z-ring constriction control remains poorly understood and (to some extent) controversial, probably due to the fact that this phenomenon is transient and controlled by numerous factors. Here, we characterize ZapE, a novel ATPase found in Gram-negative bacteria, which is required for growth under conditions of low oxygen, while loss of zapE results in temperature-dependent elongation of cell shape. We found that ZapE is recruited to the Z-ring during late stages of the cell division process and correlates with constriction of the Z-ring. Overexpression or inactivation of zapE leads to elongation of Escherichia coli and affects the dynamics of the Z-ring during division. In vitro, ZapE destabilizes FtsZ polymers in an ATP-dependent manner. PMID:24595368

An advanced retrieval algorithm for greenhouse gases using polarization information measured by GOSAT TANSO-FTS SWIR I: Simulation study

NASA Astrophysics Data System (ADS)

Kikuchi, N.; Yoshida, Y.; Uchino, O.; Morino, I.; Yokota, T.

2016-11-01

We present an algorithm for retrieving column-averaged dry air mole fraction of carbon dioxide (XCO2) and methane (XCH4) from reflected spectra in the shortwave infrared (SWIR) measured by the TANSO-FTS (Thermal And Near infrared Sensor for carbon Observation Fourier Transform Spectrometer) sensor on board the Greenhouse gases Observing SATellite (GOSAT). The algorithm uses the two linear polarizations observed by TANSO-FTS to improve corrections to the interference effects of atmospheric aerosols, which degrade the accuracy in the retrieved greenhouse gas concentrations. To account for polarization by the land surface reflection in the forward model, we introduced a bidirectional reflection matrix model that has two parameters to be retrieved simultaneously with other state parameters. The accuracy in XCO2 and XCH4 values retrieved with the algorithm was evaluated by using simulated retrievals over both land and ocean, focusing on the capability of the algorithm to correct imperfect prior knowledge of aerosols. To do this, we first generated simulated TANSO-FTS spectra using a global distribution of aerosols computed by the aerosol transport model SPRINTARS. Then the simulated spectra were submitted to the algorithms as measurements both with and without polarization information, adopting a priori profiles of aerosols that differ from the true profiles. We found that the accuracy of XCO2 and XCH4, as well as profiles of aerosols, retrieved with polarization information was considerably improved over values retrieved without polarization information, for simulated observations over land with aerosol optical thickness greater than 0.1 at 1.6 μm.

A gLite FTS based solution for managing user output in CMS

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

Cinquilli, M.; Riahi, H.; Spiga, D.

2012-01-01

The CMS distributed data analysis workflow assumes that jobs run in a different location from where their results are finally stored. Typically the user output must be transferred across the network from one site to another, possibly on a different continent or over links not necessarily validated for high bandwidth/high reliability transfer. This step is named stage-out and in CMS was originally implemented as a synchronous step of the analysis job execution. However, our experience showed the weakness of this approach both in terms of low total job execution efficiency and failure rates, wasting precious CPU resources. The nature ofmore » analysis data makes it inappropriate to use PhEDEx, the core data placement system for CMS. As part of the new generation of CMS Workload Management tools, the Asynchronous Stage-Out system (AsyncStageOut) has been developed to enable third party copy of the user output. The AsyncStageOut component manages glite FTS transfers of data from the temporary store at the site where the job ran to the final location of the data on behalf of that data owner. The tool uses python daemons, built using the WMCore framework, and CouchDB, to manage the queue of work and FTS transfers. CouchDB also provides the platform for a dedicated operations monitoring system. In this paper, we present the motivations of the asynchronous stage-out system. We give an insight into the design and the implementation of key features, describing how it is coupled with the CMS workload management system. Finally, we show the results and the commissioning experience.« less

Validation of ACE-FTS measurements of CFC-11, CFC-12, and HCFC-22 using ground-based FTIR spectrometers

NASA Astrophysics Data System (ADS)

Kolonjari, F.; Walker, K. A.; Mahieu, E.; Batchelor, R. L.; Bernath, P. F.; Boone, C.; Conway, S. A.; Dan, L.; Griffin, D.; Harrett, A.; Kasai, Y.; Kagawa, A.; Lindenmaier, R.; Strong, K.; Whaley, C.

2013-12-01

Satellite datasets can be an effective global monitoring tool for long-lived compounds in the atmosphere. The Atmospheric Chemistry Experiment (ACE) is a mission on-board the Canadian satellite SCISAT-1. The primary instrument on SCISAT-1 is a high-resolution infrared Fourier transform spectrometer (ACE-FTS) which is capable of measuring a range of gases including key chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) species. These families of species are of interest because of their significant contribution to anthropogenic ozone depletion and to global warming. To assess the quality of data derived from satellite measurements, validation using other data sources is essential. Ground-based Fourier transform infrared (FTIR) spectrometers are particularly useful for this purpose. In this study, five FTIR spectrometers located at four sites around the world are used to validate the CFC-11 (CCl3F), CFC-12 (CCl2F2), and HCFC-22 (CHClF2) retrieved profiles from ACE-FTS measurements. These species are related because HCFC-22 was the primary replacement for CFC-11 and CFC-12 in refrigerant and propellant applications. The FTIR spectrometers used in this study record solar absorption spectra at Eureka (Canada), Jungfraujoch (Switzerland), Poker Flat (USA), and Toronto (Canada). The retrieval of CFC-11, CFC-12, and HCFC-22 are not standard products for many of these instruments, and as such, a harmonization of retrieval parameters between the sites has been conducted. The retrievals of these species from the FTIR spectra are sensitive from the surface to approximately 20 km, while the ACE-FTS profiles extend from approximately 6 to 30 km. For each site, partial column comparisons between coincident measurements of the three species and a validation of the observed trends will be discussed.

78 FR 25132 - Enercorp, Inc., FTS Group, Inc., Games, Inc. (n/k/a InQBate Corporation), Hartmarx Corporation (n...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-29

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Enercorp, Inc., FTS Group, Inc., Games, Inc. (n/k/a InQBate Corporation), Hartmarx Corporation (n/k/a XMH Corp. 1), and Penn Treaty American... current and accurate information concerning the securities of Games, Inc. (n/k/a InQBate Corporation...

GOSAT field experiments with a new portable mid-IR FTS in the western US

NASA Astrophysics Data System (ADS)

Shiomi, K.; Kikuchi, N.; Kuze, A.; Suto, H.; Kawakami, S.; Hashimoto, M.; Kataoka, F.; Kasai, K.; Arai, T.; Hedelius, J.; Viatte, C.; Wennberg, P. O.; Roehl, C. M.; Leifer, I.; Yates, E. L.; Marrero, J. E.; Iraci, L. T.; Bruegge, C. J.; Schwandner, F. M.; Crisp, D.

2016-12-01

The column-average dry air mole fractions of carbon dioxide (XCO2), methane (XCH4) and carbon monoxide (XCO) were measured from the surface using direct sunlight at near-IR wavelengths. Simultaneous detection of CO is helpful to characterize CO2 source type. We measured XCO along with XCO2 and XCH4 using a new portable Fourier transform spectrometer (FTS), EM27/SUN mid-IR,in western US field experiments at 1) Caltech, in Pasadena, a northern Los Angeles suburb, 2) Chino, a dairy farming region east of Los Angeles, and 3) Railroad Valley (RRV), a desert playa in Nevada. These measurements were conducted during the GOSAT/OCO-2 joint campaign for vicarious calibration and validation (cal/val) and its preparatory experiments in the early summer of 2016. Before the campaign, measurements from the JAXA EM27/SUN mid-IR were compared with those from the Total Carbon Column Observing Network (TCCON) station at Caltech. Then, we observed a diurnal cycle at the Chino dairy site, an area of concentrated animal husbandry, producing a CH4 point source. Finally, we conducted the cal/val campaign at RRV coincident with GOSAT and OCO-2 overpass observations. Over RRV, in-situ vertical profiles of CO2 and CH4 were measured using the Alpha Jet research aircraft as a part of the NASA Ames Alpha Jet Atmospheric eXperiment (AJAX). We will compare experimental results from the cal/val campaign for XCO2 and XCH4 with the portable FTS.

influence of TEM-1 beta-lactamase on the pharmacodynamic activity of simulated total versus free-drug serum concentrations of cefditoren (400 milligrams) versus amoxicillin-clavulanic acid (2,000/125 milligrams) against Haemophilus influenzae strains exhibiting an N526K mutation in the ftsI gene.

PubMed

Torrico, M; Aguilar, L; González, N; Giménez, M J; Echeverría, O; Cafini, F; Sevillano, D; Alou, L; Coronel, P; Prieto, J

2007-10-01

The aim of this study was to explore bactericidal activity of total and free serum simulated concentrations after the oral administration of cefditoren (400 mg, twice daily [bid]) versus the oral administration of amoxicillin-clavulanic acid extended release formulation (2,000/125 mg bid) against Haemophilus influenzae. A computerized pharmacodynamic simulation was performed, and colony counts and beta-lactamase activity were determined over 48 h. Three strains were used: ampicillin-susceptible, beta-lactamase-negative ampicillin-resistant (BLNAR) (also resistant to amoxicillin-clavulanic acid) and beta-lactamase-positive amoxicillin-clavulanic acid-resistant (BLPACR) strains, with cefditoren MICs of < or =0.12 microg/ml and amoxicillin-clavulanic acid MICs of 2, 8, and 8 microg/ml, respectively. Against the ampicillin-susceptible and BLNAR strains, bactericidal activity (> or =3 log(10) reduction) was obtained from 6 h on with either total and free cefditoren or amoxicillin-clavulanic acid. Against the BLPACR strain, free cefditoren showed bactericidal activity from 8 h on. In amoxicillin-clavulanic acid simulations the increase in colony counts from 4 h on occurred in parallel with the increase in beta-lactamase activity for the BLPACR strain. Since both BLNAR and BLPACR strains exhibited the same MIC, this was due to the significantly lower (P < or = 0.012) amoxicillin concentrations from 4 h on in simulations with beta-lactamase positive versus negative strains, thus decreasing the time above MIC (T>MIC). From a pharmacodynamic point of view, the theoretical amoxicillin T>MIC against strains with elevated ampicillin/amoxicillin-clavulanic acid MICs should be considered with caution since the presence of beta-lactamase inactivates the antibiotic, thus rendering inaccurate theoretical calculations. The experimental bactericidal activity of cefditoren is maintained over the dosing interval regardless of the presence of a mutation in the ftsI gene or beta

Influence of TEM-1 β-Lactamase on the Pharmacodynamic Activity of Simulated Total versus Free-Drug Serum Concentrations of Cefditoren (400 Milligrams) versus Amoxicillin-Clavulanic Acid (2,000/125 Milligrams) against Haemophilus influenzae Strains Exhibiting an N526K Mutation in the ftsI Gene▿

PubMed Central

Torrico, M.; Aguilar, L.; González, N.; Giménez, M. J.; Echeverría, O.; Cafini, F.; Sevillano, D.; Alou, L.; Coronel, P.; Prieto, J.

2007-01-01

The aim of this study was to explore bactericidal activity of total and free serum simulated concentrations after the oral administration of cefditoren (400 mg, twice daily [bid]) versus the oral administration of amoxicillin-clavulanic acid extended release formulation (2,000/125 mg bid) against Haemophilus influenzae. A computerized pharmacodynamic simulation was performed, and colony counts and β-lactamase activity were determined over 48 h. Three strains were used: ampicillin-susceptible, β-lactamase-negative ampicillin-resistant (BLNAR) (also resistant to amoxicillin-clavulanic acid) and β-lactamase-positive amoxicillin-clavulanic acid-resistant (BLPACR) strains, with cefditoren MICs of ≤0.12 μg/ml and amoxicillin-clavulanic acid MICs of 2, 8, and 8 μg/ml, respectively. Against the ampicillin-susceptible and BLNAR strains, bactericidal activity (≥3 log10 reduction) was obtained from 6 h on with either total and free cefditoren or amoxicillin-clavulanic acid. Against the BLPACR strain, free cefditoren showed bactericidal activity from 8 h on. In amoxicillin-clavulanic acid simulations the increase in colony counts from 4 h on occurred in parallel with the increase in β-lactamase activity for the BLPACR strain. Since both BLNAR and BLPACR strains exhibited the same MIC, this was due to the significantly lower (P ≤ 0.012) amoxicillin concentrations from 4 h on in simulations with β-lactamase positive versus negative strains, thus decreasing the time above MIC (T>MIC). From a pharmacodynamic point of view, the theoretical amoxicillin T>MIC against strains with elevated ampicillin/amoxicillin-clavulanic acid MICs should be considered with caution since the presence of β-lactamase inactivates the antibiotic, thus rendering inaccurate theoretical calculations. The experimental bactericidal activity of cefditoren is maintained over the dosing interval regardless of the presence of a mutation in the ftsI gene or β-lactamase production. PMID:17664320

VizieR Online Data Catalog: Herschel SPIRE/FTS 194-671um survey of GOALS LIRGs (Lu+, 2017)

NASA Astrophysics Data System (ADS)

Lu, N.; Zhao, Y.; Diaz-Santos, T.; Xu, C. K.; Gao, Y.; Armus, L.; Isaak, K. G.; Mazzarella, J. M.; van der Werf, P. P.; Appleton, P. N.; Charmandaris, V.; Evans, A. S.; Howell, J.; Iwasawa, K.; Leech, J.; Lord, S.; Petric, A. O.; Privon, G. C.; Sanders, D. B.; Schulz, B.; Surace, J. A.

2017-06-01

In this paper we presented a Herschel SPIRE/FTS 194-671um spectroscopic survey of 121 galaxies belonging to a complete, flux-limited sample of 123 luminous infrared galaxies (LIRGs) down to a total IR flux of 6.5x10-13W/m2, selected from the Great Observatories All-Sky LIRG Survey (GOALS; Armus+ 2009PASP..121..559A). All 123 observed targets are listed in Table 1. (3 data files).

FTS Spectra from the Mayall 4-m Telescope, 1975-1995

NASA Astrophysics Data System (ADS)

Pilachowski, Catherine A.; Hinkle, Kenneth H.; Young, Michael; Dennis, Harold; Gopu, Arvind; Henschel, Robert; Hayashi, Soichi

2017-01-01

The complete archive of spectra obtained with the Fourier Transform Spectrometers in use at the Mayall 4m telescope at the Kitt Peak National Observatory from 1975 through 1995 is now available to the community. The archive is hosted at Indiana University Bloomington, and includes nearly 10,000 individual spectra of more than 800 different astronomical sources. The FTS produced spectra in the wavelength regime from roughly 0.9 to 5 microns (11,000 to 2000 cm-1), mostly at relatively high spectral resolution. The archive can be searched to identify specific spectra of interest, and the spectra can be viewed online and downloaded in FITS format for analysis. Once a spectrum of interest has been identified, all spectra taken on the same date are provided to allow users to identify appropriate hot star spectra for telluric line division.The archive can be accessed on the web at https://sparc.sca.iu.edu.

Pharmacophore generation, atom-based 3D-QSAR, molecular docking and molecular dynamics simulation studies on benzamide analogues as FtsZ inhibitors.

PubMed

Tripathy, Swayansiddha; Azam, Mohammed Afzal; Jupudi, Srikanth; Sahu, Susanta Kumar

2017-10-11

FtsZ is an appealing target for the design of antimicrobial agent that can be used to defeat the multidrug-resistant bacterial pathogens. Pharmacophore modelling, molecular docking and molecular dynamics (MD) simulation studies were performed on a series of three-substituted benzamide derivatives. In the present study a five-featured pharmacophore model with one hydrogen bond acceptors, one hydrogen bond donors, one hydrophobic and two aromatic rings was developed using 97 molecules having MIC values ranging from .07 to 957 μM. A statistically significant 3D-QSAR model was obtained using this pharmacophore hypothesis with a good correlation coefficient (R 2  = .8319), cross validated coefficient (Q 2  = .6213) and a high Fisher ratio (F = 103.9) with three component PLS factor. A good correlation between experimental and predicted activity of the training (R 2  = .83) and test set (R 2  = .67) molecules were displayed by ADHRR.1682 model. The generated model was further validated by enrichment studies using the decoy test and MAE-based criteria to measure the efficiency of the model. The docking studies of all selected inhibitors in the active site of FtsZ protein showed crucial hydrogen bond interactions with Val 207, Asn 263, Leu 209, Gly 205 and Asn-299 residues. The binding free energies of these inhibitors were calculated by the molecular mechanics/generalized born surface area VSGB 2.0 method. Finally, a 15 ns MD simulation was done to confirm the stability of the 4DXD-ligand complex. On a wider scope, the prospect of present work provides insight in designing molecules with better selective FtsZ inhibitory potential.

Using SCIAMACHY and Ground-based FTS Measurements to Test the OCO X(sub CO2) Retrieval and Validation Approach

NASA Technical Reports Server (NTRS)

Boesch, Hartmut; Toon, G.; Sen, B; Li, Q. B.; Salawitch, R.; Miller, C.; Crisp, D.; Washenfelder, R.; Wennberg, P.; Natraj, V.;

Testing forward model against OCO-2 and TANSO-FTS/GOSAT observed spectra in near infrared range

NASA Astrophysics Data System (ADS)

Zadvornykh, Ilya V.; Gribanov, Konstantin G.

2015-11-01

An existing software package FIRE-ARMS (Fine InfraRed Explorer for Atmospheric Remote MeasurementS) was modified by embedding vector radiative transfer model VLIDORT. Thus the program tool includes both thermal (TIR) and near infrared (NIR) regions. We performed forward simulation of near infrared spectra on the top of the atmosphere for outgoing radiation accounting multiple scattering in cloudless atmosphere. Simulated spectra are compared with spectra measured by TANSO-FTS/GOSAT and OCO-2 in the condition of cloudless atmosphere over Western Siberia. NCEP/NCAR reanalysis data were used to complete model atmosphere.

The FTS atomic spectrum tool (FAST) for rapid analysis of line spectra

NASA Astrophysics Data System (ADS)

Ruffoni, M. P.

2013-07-01

The FTS Atomic Spectrum Tool (FAST) is an interactive graphical program designed to simplify the analysis of atomic emission line spectra obtained from Fourier transform spectrometers. Calculated, predicted and/or known experimental line parameters are loaded alongside experimentally observed spectral line profiles for easy comparison between new experimental data and existing results. Many such line profiles, which could span numerous spectra, may be viewed simultaneously to help the user detect problems from line blending or self-absorption. Once the user has determined that their experimental line profile fits are good, a key feature of FAST is the ability to calculate atomic branching fractions, transition probabilities, and oscillator strengths-and their uncertainties-which is not provided by existing analysis packages. Program SummaryProgram title: FAST: The FTS Atomic Spectrum Tool Catalogue identifier: AEOW_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEOW_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 3 No. of lines in distributed program, including test data, etc.: 293058 No. of bytes in distributed program, including test data, etc.: 13809509 Distribution format: tar.gz Programming language: C++. Computer: Intel x86-based systems. Operating system: Linux/Unix/Windows. RAM: 8 MB minimum. About 50-200 MB for a typical analysis. Classification: 2.2, 2.3, 21.2. Nature of problem: Visualisation of atomic line spectra including the comparison of theoretical line parameters with experimental atomic line profiles. Accurate intensity calibration of experimental spectra, and the determination of observed relative line intensities that are needed for calculating atomic branching fractions and oscillator strengths. Solution method: FAST is centred around a graphical interface, where a user may view sets of experimental line profiles and compare

Distributions and Seasonal Variations of Tropospheric Ethene (C2H4) from Atmospheric Chemistry Experiment (ACE-FTS) Solar Occultation Spectra

NASA Technical Reports Server (NTRS)

Herbin, H.; Hurtmans, D.; Clarisse, L.; Turquety, S.; Clerbaux, C.; Rinsland, Curtis P.; Boone, C.; Bernath, P. F.; Coheur, P.-F.

2009-01-01

This work reports the first measurements of ethene (C2H4) distributions in the upper troposphere. These are obtained by retrieving vertical profiles from 5 to 20 km from infrared solar occultation spectra recorded in 2005 and 2006 by the Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS). Background volume mixin^ ratios (vmrs) ranging from a few to about 50 pptv (10(exp -1) are measured at the different altitudes, while for certain occultations, vmrs as high as 200 pptv are observed. Zonal distributions and vertically resolved latitudinal distributions are derived for the two year period analyzed, highlighting spatial - including a North-South gradient - as well as seasonal variations. We show the latter to be more pronounced at the highest latitudes, presumably as a result of less active photochemistry during winter. The observation of C2H4 enhancements in remote Arctic regions at high latitudes is consistent with the occurrence of fast transport processes of gaseous pollution from the continents leading to Arctic haze. Citation: Herbin, H., D. Hurtmans, L. Clarisse, S. Turquety, C. Clerbaux, C. P. Rinsland, C. Boone, P. F. Bernath, and P.-F. Colieur (2009), Distributions and seasonal variations of tropospheric ethene (C2H4) from Atmospheric Chemistry Experiment (ACE-FTS) solar occultation spectra,

The Arabidopsis minE mutation causes new plastid and FtsZ1 localization phenotypes in the leaf epidermis

PubMed Central

Fujiwara, Makoto T.; Kojo, Kei H.; Kazama, Yusuke; Sasaki, Shun; Abe, Tomoko; Itoh, Ryuuichi D.

2015-01-01

Plastids in the leaf epidermal cells of plants are regarded as immature chloroplasts that, like mesophyll chloroplasts, undergo binary fission. While mesophyll chloroplasts have generally been used to study plastid division, recent studies have suggested the presence of tissue- or plastid type-dependent regulation of plastid division. Here, we report the detailed morphology of plastids and their stromules, and the intraplastidic localization of the chloroplast division-related protein AtFtsZ1-1, in the leaf epidermis of an Arabidopsis mutant that harbors a mutation in the chloroplast division site determinant gene AtMinE1. In atminE1, the size and shape of epidermal plastids varied widely, which contrasts with the plastid phenotype observed in atminE1 mesophyll cells. In particular, atminE1 epidermal plastids occasionally displayed grape-like morphology, a novel phenotype induced by a plastid division mutation. Observation of an atminE1 transgenic line harboring an AtMinE1 promoter::AtMinE1-yellow fluorescent protein fusion gene confirmed the expression and plastidic localization of AtMinE1 in the leaf epidermis. Further examination revealed that constriction of plastids and stromules mediated by the FtsZ1 ring contributed to the plastid pleomorphism in the atminE1 epidermis. These results illustrate that a single plastid division mutation can have dramatic consequences for epidermal plastid morphology, thereby implying that plastid division and morphogenesis are differentially regulated in epidermal and mesophyll plastids. PMID:26500667

Oxacillin sensitization of methicillin-resistant Staphylococcus aureus and methicillin-resistant Staphylococcus pseudintermedius by antisense peptide nucleic acids in vitro.

PubMed

Goh, Shan; Loeffler, Anette; Lloyd, David H; Nair, Sean P; Good, Liam

2015-11-11

Antibiotic resistance genes can be targeted by antisense agents, which can reduce their expression and thus restore cellular susceptibility to existing antibiotics. Antisense inhibitors can be gene and pathogen specific, or designed to inhibit a group of bacteria having conserved sequences within resistance genes. Here, we aimed to develop antisense peptide nucleic acids (PNAs) that could be used to effectively restore susceptibility to β-lactams in methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus pseudintermedius (MRSP). Antisense PNAs specific for conserved regions of the mobilisable gene mecA, and the growth essential gene, ftsZ, were designed. Clinical MRSA and MRSP strains of high oxacillin resistance were treated with PNAs and assayed for reduction in colony forming units on oxacillin plates, reduction in target gene mRNA levels, and cell size. Anti-mecA PNA at 7.5 and 2.5 μM reduced mecA mRNA in MRSA and MRSP (p < 0.05). At these PNA concentrations, 66 % of MRSA and 92 % of MRSP cells were killed by oxacillin (p < 0.01). Anti-ftsZ PNA at 7.5 and 2.5 μM reduced ftsZ mRNA in MRSA and MRSP, respectively (p ≤ 0.05). At these PNA concentrations, 86 % of MRSA cells and 95 % of MRSP cells were killed by oxacillin (p < 0.05). Anti-ftsZ PNAs resulted in swelling of bacterial cells. Scrambled PNA controls did not affect MRSA but sensitized MRSP moderately to oxacillin without affecting mRNA levels. The antisense PNAs effects observed provide in vitro proof of concept that this approach can be used to reverse β-lactam resistance in staphylococci. Further studies are warranted as clinical treatment alternatives are needed.

Absolute Rovibrational Intensities for the Chi(sup 1)Sigma(sup +) v=3 <-- 0 Band of (12)C(16)O Obtained with Kitt Peak and BOMEM FTS Instruments

NASA Technical Reports Server (NTRS)

Chackerian, Charles, Jr.; Kshirsagar, R. J.; Giver, L. P.; Brown, L. R.; Condon, Estelle P. (Technical Monitor)

1999-01-01

This work was initiated to compare absolute line intensities retrieved with the Kitt Peak FTS (Fourier Transform Spectrometer) and Ames BOMEM FTS. Since thermal contaminations can be a problem using the BOMEM instrument if proper precautions are not taken it was thought that measurements done at 6300 per cm would more easily result in satisfactory intercomparisons. Very recent measurements of the CO 3 <-- 0 band fine intensities confirms results reported here that the intensities listed in HITRAN (High Resolution Molecular Absorption Database) for this band are on the order of six to seven percent too low. All of the infrared intensities in the current HITRAN tabulation are based on the electric dipole moment function reported fifteen years ago. The latter in turn was partly based on intensities for the 3 <-- 0 band reported thirty years ago. We have, therefore, redetermined the electric dipole moment function of ground electronic state CO.

Efficacy of simulated cefditoren versus amoxicillin-clavulanate free concentrations in countering intrastrain ftsI gene diffusion in Haemophilus influenzae.

PubMed

González, Natalia; Aguilar, Lorenzo; Sevillano, David; Giménez, Maria-Jose; Alou, Luis; Cafini, Fabio; Torrico, Martha; López, Ana-Maria; Coronel, Pilar; Prieto, Jose

2011-06-01

This study explores the effects of cefditoren (CDN) versus amoxicillin-clavulanic acid (AMC) on the evolution (within a single strain) of total and recombined populations derived from intrastrain ftsI gene diffusion in β-lactamase-positive (BL⁺) and β-lactamase-negative (BL⁻) Haemophilus influenzae. DNA from β-lactamase-negative, ampicillin-resistant (BLNAR) isolates (DNA(BLNAR)) and from β-lactamase-positive, amoxicillin-clavulanate-resistant (BLPACR) (DNA(BLPACR)) isolates was extracted and added to a 10⁷-CFU/ml suspension of one BL⁺ strain (CDN MIC, 0.007 μg/ml; AMC MIC, 1 μg/ml) or one BL⁻ strain (CDN MIC, 0.015 μg/ml; AMC MIC, 0.5 μg/ml) in Haemophilus Test Medium (HTM). The mixture was incubated for 3 h and was then inoculated into a two-compartment computerized device simulating free concentrations of CDN (400 mg twice a day [b.i.d.]) or AMC (875 and 125 mg three times a day [t.i.d.]) in serum over 24 h. Controls were antibiotic-free simulations. Colony counts were performed; the total population and the recombined population were differentiated; and postsimulation MICs were determined. At time zero, the recombined population was 0.00095% of the total population. In controls, the BL⁻ and BL⁺ total populations and the BL⁻ recombined population increased (from ≈3 log₁₀ to 4.5 to 5 log₁₀), while the BL⁺ recombined population was maintained in simulations with DNA(BLPACR) and was decreased by ≈2 log₁₀ with DNA(BLNAR). CDN was bactericidal (percentage of the dosing interval for which experimental antibiotic concentrations exceeded the MIC [ft>MIC], >88%), and no recombined populations were detected from 4 h on. AMC was bactericidal against BL⁻ strains (ft>MIC, 74.0%) in DNA(BLNAR) and DNA(BLPACR) simulations, with a small final recombined population (MIC, 4 μg/ml; ft>MIC, 30.7%) in DNA(BLPACR) simulations. When AMC was used against the BL⁺ strain (in DNA(BLNAR) or DNA(BLPACR) simulations), the bacterial load was

Four Fourier transform spectrometers and the Arctic polar vortex: instrument intercomparison and ACE-FTS validation at Eureka during the IPY springs of 2007 and 2008

NASA Astrophysics Data System (ADS)

Batchelor, R. L.; Kolonjari, F.; Lindenmaier, R.; Mittermeier, R. L.; Daffer, W.; Fast, H.; Manney, G.; Strong, K.; Walker, K. A.

2009-11-01

The Canadian Arctic Atmospheric Chemistry Experiment Validation Campaigns have been carried out at Eureka, Nunavut (80.05° N, 86.42° W) during the polar sunrise period since 2004. During the International Polar Year (IPY) springs of 2007 and 2008, three ground-based Fourier transform infrared (FTIR) spectrometers were operated simultaneously. This paper presents a comparison of trace gas measurements of stratospherically important species involved in ozone depletion, namely O3, HCl, ClONO2, HNO3 and HF, recorded with these three spectrometers. Total column densities of the gases measured with the new Canadian Network for the Detection of Atmospheric Change (CANDAC) Bruker 125HR are shown to agree to within 3.5% with the existing Environment Canada Bomem DA8 measurements. After smoothing both of these sets of measurements to account for the lower spectral resolution of the University of Waterloo Portable Atmospheric Research Interferometric Spectrometer for the Infrared (PARIS-IR), the measurements were likewise shown to agree with PARIS-IR to within 7%. Concurrent measurements of these gases were also made with the satellite-based Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) during overpasses of Eureka during these time periods. While one of the mandates of the ACE satellite mission is to study ozone depletion in the polar spring, previous validation exercises have identified the highly variable polar vortex conditions of the spring period to be a challenge for validation efforts. In this work, comparisons between the CANDAC Bruker 125HR and ACE-FTS have been used to develop strict criteria that allow the ground- and satellite-based instruments to be confidently compared. When these criteria are taken into consideration, there is shown to be no significant bias between the ACE-FTS and ground-based FTIR spectrometer for any of these gases.

Influence of oxalate ligand functionalization on Co/ZSM-5 activity in Fischer Tropsch synthesis and hydrodeoxygenation of oleic acid into hydrocarbon fuels.

PubMed

Ayodele, Olumide Bolarinwa

2017-08-30

Achieving high degree of active metal dispersions at the highest possible metal loading and high reducibility of the metal remains a challenge in Fischer Tropsch synthesis (FTS) as well as in hydrogeoxygenation (HDO).This study therefore reports the influence of oxalic acid (OxA) functionalization on the metal dispersion, reducibility and activity of Co supported ZSM-5 catalyst in FTS and HDO of oleic acid into paraffin biofuel. The Brunauer-Emmett-Teller (BET) results showed that cobalt oxalate supported ZSM-5 catalyst (CoOx/ZSM-5) synthesized from the incorporation of freshly prepared cobalt oxalate complex into ZSM-5 displayed increase in surface area, pore volume and average pore size while the nonfunctionalized cobalt supported on ZSM-5 (Co/ZSM-5) catalyst showed reduction in those properties. Furthermore, both XRD and XPS confirmed the presence of Co° formed from the decomposition of CoOx during calcination of CoOx/ZSM-5 under inert atmosphere. The HRTEM showed that Co species average particle sizes were smaller in CoOx/ZSM-5 than in Co/ZSM-5, and in addition, CoOx/ZSM-5 shows a clear higher degree of active metal dispersion. The FTS result showed that at CO conversion over Co/ZSM-5 and CoOx/ZSM-5 catalysts were 74.28% and 94.23% and their selectivity to C 5+ HC production were 63.15% and 75.4%, respectively at 4 h TOS. The HDO result also showed that the CoOx/ZSM-5 has higher OA conversion of 92% compared to 59% over Co/ZSM-5. In addition CoOx/ZSM-5 showed higher HDO and isomerization activities compared to Co/ZSM-5.

Remote sensing of trend and seasonal variability of greenhouse gas emissions from the Los Angeles basin using an FTS on Mount Wilson

NASA Astrophysics Data System (ADS)

Wong, C.; Fu, D.; Pongetti, T. J.; Newman, S.; Yung, Y. L.; Sander, S. P.

2013-12-01

Cities, such as Los Angeles, are significant sources of anthropogenic greenhouse gases (GHGs). With the growth of populations in cities worldwide, GHG emissions will increase, and monitoring the temporal trends will provide crucial data for global climate models as well as assessments of the effectiveness of control policies. Currently, continuous GHG observations in the Los Angeles basin are limited to a few in situ measurements, which are shown to be sensitive to local emissions and do not represent the Los Angeles basin well. To quantify GHG emissions from the metropolitan area, which tend to have heterogeneous characteristics, it is important to perform measurements which provide both continuous temporal and spatial coverage of the domain. Here we present observations of the major greenhouse gases, CO2 and CH4, using a spectroscopic remote sensing technique from the California Laboratory for Atmospheric Remote Sensing (CLARS) at Mount Wilson, California (1.7 km elevation). A Fourier Transform Spectrometer (FTS) deployed at the CLARS site points downward at 28 selected land surfaces in the Los Angeles basin to measure the slant column abundances of CO2, CH4, N2O, CO and O2 using reflected sunlight in the near-infrared and shortwave infrared regions. This remote sensing technique provides continuous temporal and spatial measurements in the Los Angeles basin to achieve the goal of quantifying emissions of GHGs and CO. It also serves as a test-bed for future geostationary satellite missions to measure GHGs from space such as JPL's Geostationary Carbon Process Investigation (GCPI). The path-averaged dry-air mixing ratio, XCO2 and XCH4, observed by the CLARS FTS, show significant diurnal variability that arises from emissions in the Los Angeles basin and atmospheric transport processes. High-precision data have been collected since August 2011. Here we analyze the annual and seasonal trend of the ratio XCH4:XCO2 in the Los Angeles basin observed by the CLARS FTS from

Transmission spectroscopy with the ACE-FTS infrared spectral atlas of Earth: A model validation and feasibility study

NASA Astrophysics Data System (ADS)

Schreier, Franz; Städt, Steffen; Hedelt, Pascal; Godolt, Mareike

2018-06-01

Infrared solar occultation measurements are well established for remote sensing of Earth's atmosphere, and the corresponding primary transit spectroscopy has turned out to be valuable for characterization of extrasolar planets. Our objective is an assessment of the detectability of molecular signatures in Earth's transit spectra. To this end, we take a limb sequence of representative cloud-free transmission spectra recorded by the space-borne ACE-FTS Earth observation mission (Hughes et al., ACE infrared spectral atlases of the Earth's atmosphere, JQSRT 2014) and combine these spectra to the effective height of the atmosphere. These data are compared to spectra modeled with an atmospheric radiative transfer line-by-line infrared code to study the impact of individual molecules, spectral resolution, the choice of auxiliary data, and numerical approximations. Moreover, the study serves as a validation of our infrared radiative transfer code. The largest impact is due to water, carbon dioxide, ozone, methane, nitrous oxide, nitrogen, nitric acid, oxygen, and some chlorofluorocarbons (CFC11 and CFC12). The effect of further molecules considered in the modeling is either marginal or absent. The best matching model has a mean residuum of 0.4 km and a maximum difference of 2 km to the measured effective height. For a quantitative estimate of visibility and detectability we consider the maximum change of the residual spectrum, the relative change of the residual norm, the additional transit depth, and signal-to-noise ratios for a JWST setup. In conclusion, our study provides a list of molecules that are relevant for modeling transmission spectra of Earth-like exoplanets and discusses the feasibility of retrieval.

Improved Micellar Formulation for Enhanced Delivery for Paclitaxel.

PubMed

Xu, Jieni; Zhang, Xiaolan; Chen, Yichao; Huang, Yixian; Wang, Pengcheng; Wei, Yuan; Ma, Xiaochao; Li, Song

2017-01-03

We have previously improved the bioactivity of PEG 5k -FTS 2 system by incorporating disulfide bond (PEG 5k -S-S-FTS 2 ) to facilitate the release of farnesyl thiosalicylic acid (FTS).1 Later, fluorenylmethyloxycarbonyl (Fmoc) moiety has been introduced to PEG 5k -FTS 2 system (PEG 5k -Fmoc-FTS 2 ) in order to enhance drug loading capacity (DLC) and formulation stability.2 In this study, we have brought in both disulfide linkage and Fmoc group to PEG 5k -FTS 2 to form a simple PEG 5k -Fmoc-S-S-FTS 2 micellar system. PEG 5k -Fmoc-S-S-FTS 2 conjugate formed filamentous micelles with a ∼10-fold decrease in critical micellar concentration (CMC). Compared with PEG 5k -Fmoc-FTS 2 , our novel system exhibited further strengthened DLC and colloidal stability. More FTS was freed from PEG 5k -Fmoc-S-S-FTS 2 in treated tumor cells compared to PEG 5k -Fmoc-FTS 2 , which was correlated to an increased cytotoxicity of our new carrier in these cancer cells. After loading Paclitaxel (PTX) into PEG 5k -Fmoc-S-S-FTS 2 micelles, it showed more potent efficiency in inhibition of tumor cell proliferation than Taxol and PTX-loaded PEG 5k -Fmoc-FTS 2 . PTX release kinetics of PTX/PEG 5k -Fmoc-S-S-FTS 2 was much slower than that of Taxol and PTX/PEG 5k -Fmoc-FTS 2 in normal release medium. In contrast, in glutathione (GSH)-containing medium, PTX in PEG 5k -Fmoc-S-S-FTS 2 micelles revealed faster and more complete release. Pharmacokinetics and tissue distribution study showed that our PEG 5k -Fmoc-S-S-FTS 2 system maintained PTX in circulation for a longer time and delivered more PTX to tumor sites with less accumulation in major organs. Finally, PTX-loaded PEG 5k -Fmoc-S-S-FTS 2 micelles resulted in a superior therapeutic effect in vivo compared to Taxol and PTX formulated in PEG 5k -Fmoc-FTS 2 micelles.

Supersonic Free-jet Quantum Cascade Laser Measurements of v4 for CF3(35)Cl and CF3(37)Cl and FTS Measurements from 400 to 1260 cm-1

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

Kelly, James F; Maki, Arthur; Blake, Thomas A

2008-11-01

A supersonic free-jet spectrum of the v 4 band of CF3Cl has been measured using a quantum cascade laser system. Those measurements were combined with a low temperature (-67 C) FTS spectrum of the region 1060 to 1260 cm-1 and with room temperature FTS measurements down to 400 cm -1 to give improved values for the rovibrational constants for the v1, v2, v3, 2v3, 2v5, v4, and v5 states of CF335Cl and CF337Cl. The principal perturbation found by earlier investigators in the v1 band is treated as a very weak Coriolis interaction at several avoided crossings of the rotational levelsmore » of the v1 state and the 2v5 state with kl < 0. None of the other vibrational states showed any signs of perturbations. With these new measurements we now have high resolution data on all of the fundamental vibrational states except v6.« less

Association of Amino Acid Substitutions in Penicillin-Binding Protein 3 with β-Lactam Resistance in β-Lactamase-Negative Ampicillin-Resistant Haemophilus influenzae

PubMed Central

Ubukata, Kimiko; Shibasaki, Yumi; Yamamoto, Kentarou; Chiba, Naoko; Hasegawa, Keiko; Takeuchi, Yasuo; Sunakawa, Keisuke; Inoue, Matsuhisa; Konno, Masatoshi

2001-01-01

The affinity of [3H]benzylpenicillin for penicillin-binding protein (PBP) 3A was reduced in 25 clinical isolates of β-lactamase-negative ampicillin (AMP)-resistant (BLNAR) Haemophilus influenzae for which the AMP MIC was ≥1.0 μg/ml. The affinities of PBP 3B and PBP 4 were also reduced in some strains. The sequences of the ftsI gene encoding the transpeptidase domain of PBP 3A and/or PBP 3B and of the dacB gene encoding PBP 4 were determined for these strains and compared to those of AMP-susceptible Rd strains. The BLNAR strains were classified into three groups on the basis of deduced amino acid substitutions in the ftsI gene, which is thought to be involved in septal peptidoglycan synthesis. His-517, near the conserved Lys-Thr-Gly (KTG) motif, was substituted for Arg-517 in group I strains (n = 9), and Lys-526 was substituted for Asn-526 in group II strains (n = 12). In group III strains (n = 4), three residues (Met-377, Ser-385, and Leu-389), positioned near the conserved Ser-Ser-Asn (SSN) motif, were replaced with Ile, Thr, and Phe, respectively, in addition to the replacement with Lys-526. The MICs of cephem antibiotics with relatively high affinities for PBP 3A and PBP 3B were higher than those of AMP and meropenem for group III strains. The MICs of β-lactams for H. influenzae transformants into which the ftsI gene from BLNAR strains was introduced were as high as those for the donors, and PBP 3A and PBP 3B showed decreased affinities for β-lactams. There was no clear relationship between 7-bp deletions in the dacB gene and AMP susceptibility. Even though mutations in another gene(s) may be involved in β-lactam resistance, these data indicate that mutations in the ftsI gene are the most important for development of resistance to β-lactams in BLNAR strains. PMID:11353613

UTLS Drift Analysis for the ACE-FTS and MIPAS CFC-11 and CFC-12 Data Products

NASA Astrophysics Data System (ADS)

Walker, K. A.; Zou, J.; Sheese, P.; Boone, C. D.; Stiller, G. P.; von Clarmann, T.

2017-12-01

To progress from monitoring atmospheric composition to investigating and quantifying atmospheric changes, well-characterized measurements over many years are required. The long lifetime of the Atmospheric Chemistry Experiment (ACE) has provided more than a decade of composition measurements that contribute to our understanding of ozone recovery, climate change and pollutant emissions. To enable the generation of climate data records using multiple data sets, characterization of the "drift" between data sets is required. This study will analyze and compare the time series of chlorofluorocarbon (CFC) measurements from two infrared satellite sensors, the ACE-Fourier Transform Spectrometer (ACE-FTS) and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). With a focus on the upper troposphere-lower stratosphere, the long-term trend as well as annual, semi-annual and quasi-biennial oscillation terms derived from each data set will be compared for different altitude and latitude regions.

Four Fourier transform spectrometers and the Arctic polar vortex: instrument intercomparison and ACE-FTS validation at Eureka during the IPY springs of 2007 and 2008

NASA Astrophysics Data System (ADS)

Batchelor, R. L.; Kolonjari, F.; Lindenmaier, R.; Mittermeier, R. L.; Daffer, W.; Fast, H.; Manney, G.; Strong, K.; Walker, K. A.

2010-01-01

The Canadian Arctic Atmospheric Chemistry Experiment Validation Campaigns have been carried out at Eureka, Nunavut (80.05° N, 86.42° W) during the polar sunrise period since 2004. During the International Polar Year (IPY) springs of 2007 and 2008, three ground-based Fourier transform infrared (FTIR) spectrometers were operated simultaneously. This paper presents a comparison of trace gas measurements of stratospherically important species involved in ozone depletion, namely O3, HCl, ClONO2, HNO3 and HF, recorded with these three spectrometers. Total column densities of the gases measured with the new Canadian Network for the Detection of Atmospheric Change (CANDAC) Bruker 125HR are shown to agree to within 3.5% with the existing Environment Canada Bomem DA8 measurements. After smoothing both of these sets of measurements to account for the lower spectral resolution of the University of Waterloo Portable Atmospheric Research Interferometric Spectrometer for the Infrared (PARIS-IR), the measurements were likewise shown to agree with PARIS-IR to within 7%. Concurrent measurements of these gases were also made with the satellite-based Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) during overpasses of Eureka during these time periods. While one of the mandates of the ACE satellite mission is to study ozone depletion in the polar spring, previous validation exercises have identified the highly variable polar vortex conditions of the spring period to be a challenge for validation efforts. In this work, comparisons between the CANDAC Bruker 125HR and ACE-FTS have been used to develop strict criteria that allow the ground- and satellite-based instruments to be confidently compared. When these criteria are taken into consideration, the observed biases between the ACE-FTS and ground-based FTIR spectrometer are not persistent for both years and are generally insignificant, though small positive biases of ~5%, comparable in magnitude to those seen

Multispectral information for gas and aerosol retrieval from TANSO-FTS instrument

NASA Astrophysics Data System (ADS)

Herbin, H.; Labonnote, L. C.; Dubuisson, P.

2012-11-01

The Greenhouse gases Observing SATellite (GOSAT) mission and in particular TANSO-FTS instrument has the advantage to measure simultaneously the same field of view in different spectral ranges with a high spectral resolution. These features are promising to improve, not only, gaseous retrieval in clear sky or scattering atmosphere, but also to retrieve aerosol parameters. Therefore, this paper is dedicated to an Information Content (IC) analysis of potential synergy between thermal infrared, shortwave infrared and visible, in order to obtain a more accurate retrieval of gas and aerosol. The latter is based on Shannon theory and used a sophisticated radiative transfer algorithm developed at "Laboratoire d'Optique Atmosphérique", dealing with multiple scattering. This forward model can be relied to an optimal estimation method, which allows simultaneously retrieving gases profiles and aerosol granulometry and concentration. The analysis of the information provided by the spectral synergy is based on climatology of dust, volcanic ash and biomass burning aerosols. This work was conducted in order to develop a powerful tool that allows retrieving simultaneously not only the gas concentrations but also the aerosol characteristics by selecting the so called "best channels", i.e. the channels that bring most of the information concerning gas and aerosol. The methodology developed in this paper could also be used to define the specifications of future high spectral resolution mission to reach a given accuracy on retrieved parameters.

CO Seasonal Variability and Trend over Paris Megacity Using Ground-Based QualAir FTS and Satellite IASI-MetOp Measurements

NASA Astrophysics Data System (ADS)

Te, Yao; Jeseck, Pascal; Hadji-Lazaro, Juliette

2012-11-01

In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants are increasing continuously. Monitoring and control of atmospheric pollutants in megacities have become a major challenge for scientists and public health authorities in environmental research area. The QualAir platform at University Pierre et Marie Curie (UPMC), is an innovating experimental research platform dedicated to survey urban atmospheric pollution and air quality. A Bruker Optics IFS 125HR Fourier transform spectrometer belonged to the Laboratoire de Physique Moléculaire pour l'Atmosphère et l'Astrophysique (LPMAA), was adapted for ground-based atmospheric measurements. As one of the major instruments of the QualAir platform, this ground-based Fourier transform spectrometer (QualAir FTS) analyses the composition of the urban atmosphere of Paris, which is the third largest European megacity. The continuous monitoring of atmospheric pollutants is essential to improve the understanding of urban air pollution processes. Associated with a sun-tracker, the QualAir remote sensing FTS operates in solar infrared absorption and enables to monitor many trace gases, and to follow up their variability in the Ile-de-France region. Concentrations of atmospheric pollutants are retrieved by the radiative transfer model PROFFIT. These ground-based remote sensing measurements are compared to ground in-situ measurements and to satellite data from IASI-MetOp (Infrared Atmospheric Sounding Interferometer). The remote sensing total column of the carbon monoxide (CO) obtained from January 2009 to June 2012, has a seasonal variability with a maximum in April and a minimum in October. While, after 2008, the mean CO level is quite stable (no significant decrease as before 2008).

A novel membrane-bound toxin for cell division, CptA (YgfX), inhibits polymerization of cytoskeleton proteins, FtsZ and MreB, in Escherichia coli.

PubMed

Masuda, Hisako; Tan, Qian; Awano, Naoki; Yamaguchi, Yoshihiro; Inouye, Masayori

2012-03-01

Nearly all free-living bacteria carry toxin-antitoxin (TA) systems on their genomes, through which cell growth and death are regulated. Toxins target a variety of essential cellular functions, including DNA replication, translation, and cell division. Here, we identified a novel toxin, YgfX, on the Escherichia coli genome. The toxin, consisting of 135 residues, is composed of the N-terminal membrane domain, which encompasses two transmembrane segments, and the C-terminal cytoplasmic domain. Upon YgfX expression, the cells were initially elongated and then the middle portion of the cells became inflated to form a lemon shape. YgfX was found to interact with MreB and FtsZ, two essential cytoskeletal proteins in E. coli. The cytoplasmic domain [YgfX(C)] was found to be responsible for the YgfX toxicity, as purified YgfX(C) was found to block the polymerization of FtsZ and MreB in vitro. YgfY, located immediately upstream of YgfX, was shown to be the cognate antitoxin; notably, YgfX is the first membrane-associating toxin in bacterial TA systems. We propose to rename the toxin and the antitoxin as CptA and CptB (for Cytoskeleton Polymerization inhibiting Toxin), respectively. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Process studies with airborne GLORIA limb-imaging FTS observations during the Arctic winter 2015/16

NASA Astrophysics Data System (ADS)

Woiwode, W.; Bramberger, M.; Braun, M.; Dörnbrack, A.; Friedl-Vallon, F.; Grooss, J. U.; Hoepfner, M.; Johansson, S.; Latzko, T.; Oelhaf, H.; Orphal, J.; Preusse, P.; Sinnhuber, B. M.; Suminska-Ebersoldt, O.; Ungermann, J.

2017-12-01

The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) limb-imaging infrared Fourier-Transform Spectrometer (FTS) was deployed on board the High Altitude and LOng range research aircraft (HALO) from December 2015 until March 2016 for process studies in the Arctic and mid-latitudes. Operations were carried out from Kiruna (Sweden, 68°N) and Oberpfaffenhofen (Germany, 48°N) in the framework of the combined POLSTRACC/GW-LCYCLE/SALSA (PGS) campaigns, including 18 scientific HALO flights and about 156 flight hours. After a brief overview of the instrument, examples of process studies using GLORIA high spectral resolution mode observations will be given: (1) Strong nitrification of the Arctic lowermost stratosphere during the exceptionally cold stratospheric winter 2015/16 and comparisons with CLaMS (Chemical Lagrangian Model of the Stratosphere) chemistry transport simulations. (ii) A case study involving high-resolution ECMWF (European Centre for Medium-Range Weather Forecasts) IFS (Integrated Forecasting System) data, investigating the meridional structure of a tropopause fold interfering with a mountain wave.

Depolymerization dynamics of individual filaments of bacterial cytoskeletal protein FtsZ

PubMed Central

Mateos-Gil, Pablo; Paez, Alfonso; Hörger, Ines; Rivas, Germán; Vicente, Miguel; Tarazona, Pedro; Vélez, Marisela

2012-01-01

We report observation and analysis of the depolymerization filaments of the bacterial cytoskeletal protein FtsZ (filament temperature-sensitive Z) formed on a mica surface. At low concentration, proteins adsorbed on the surface polymerize forming curved filaments that close into rings that remain stable for some time before opening irreversibly and fully depolymerizing. The distribution of ring lifetimes (T) as a function of length (N), shows that the rate of ring aperture correlates with filament length. If this ring lifetime is expressed as a bond survival time, (Tb ≡ NT), this correlation is abolished, indicating that these rupture events occur randomly and independently at each monomer interface. After rings open irreversibly, depolymerization of the remaining filaments is fast, but can be slowed down and followed using a nonhydrolyzing GTP analogue. The histogram of depolymerization velocities of individual filaments has an asymmetric distribution that can be fit with a computer model that assumes two rupture rates, a slow one similar to the one observed for ring aperture, affecting monomers in the central part of the filaments, and a faster one affecting monomers closer to the open ends. From the quantitative analysis, we conclude that the depolymerization rate is affected both by nucleotide hydrolysis rate and by its exchange along the filament, that all monomer interfaces are equally competent for hydrolysis, although depolymerization is faster at the open ends than in central filament regions, and that all monomer–monomer interactions, regardless of the nucleotide present, can adopt a curved configuration. PMID:22566654

Evaluation of bias in lower and middle tropospheric GOSAT/TANSO-FTS TIR V1.0 CO2 data through comparisons with aircraft and NICAM-TM CO2 data

NASA Astrophysics Data System (ADS)

Saitoh, N.; Hatta, H.; Imasu, R.; Shiomi, K.; Kuze, A.; Niwa, Y.; Machida, T.; Sawa, Y.; Matsueda, H.

2016-12-01

Thermal and Near Infrared Sensor for Carbon Observation (TANSO)-Fourier Transform Spectrometer (FTS) on board the Greenhouse Gases Observing Satellite (GOSAT) has been observing carbon dioxide (CO2) concentrations in several atmospheric layers in the thermal infrared (TIR) band since its launch on 23 January 2009. We have compared TANSO-FTS TIR Version 1 (V1) CO2 data from 2010 to 2012 and CO2 data obtained by the Continuous CO2 Measuring Equipment (CME) installed on several JAL aircraft in the framework of the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project to evaluate bias in the TIR CO2 data in the lower and middle troposphere. Here, we have regarded the CME data obtained during the ascent and descent flights over several airports as part of CO2 vertical profiles there. The comparisons showed that the TIR V1 CO2 data had a negative bias against the CME CO2 data; the magnitude of the bias varied depending on season and latitude. We have estimated bias correction values for the TIR V1 lower and middle tropospheric CO2 data in each latitude band from 40°S to 60°N in each season on the basis of the comparisons with the CME CO2 profiles in limited areas over airports, applied the bias correction values to the TIR V1 CO2 data, and evaluated the quality of the bias-corrected TIR CO2 data globally through comparisons with CO2 data taken from the Nonhydrostatic Icosahedral Atmospheric Model (NICAM)-based Transport Model (TM). The bias-corrected TIR CO2 data showed a better agreement with the NICAM-TM CO2 than the original TIR data, which suggests that the bias correction values estimated in the limited areas are basically applicable to global TIR CO2 data. We have compared XCO2 data calculated from both the original and bias-corrected TIR CO2 data with TANSO-FTS SWIR and NICAM-TM XCO2 data; both the TIR XCO2 data agreed with SWIR and NICAM-TM XCO2 data within 1% except over the Sahara desert and strong source and sink regions.

Ras Signaling Inhibitors Attenuate Disease in Adjuvant-Induced Arthritis via Targeting Pathogenic Antigen-Specific Th17-Type Cells.

PubMed

Zayoud, Morad; Marcu-Malina, Victoria; Vax, Einav; Jacob-Hirsch, Jasmine; Elad-Sfadia, Galit; Barshack, Iris; Kloog, Yoel; Goldstein, Itamar

2017-01-01

The Ras family of GTPases plays an important role in signaling nodes downstream to T cell receptor and CD28 activation, potentially lowering the threshold for T-cell receptor activation by autoantigens. Somatic mutation in NRAS or KRAS may cause a rare autoimmune disorder coupled with abnormal expansion of lymphocytes. T cells from rheumatoid arthritis (RA) patients show excessive activation of Ras/MEK/ERK pathway. The small molecule farnesylthiosalicylic acid (FTS) interferes with the interaction between Ras GTPases and their prenyl-binding chaperones to inhibit proper plasma membrane localization. In the present study, we tested the therapeutic and immunomodulatory effects of FTS and its derivative 5-fluoro-FTS (F-FTS) in the rat adjuvant-induced arthritis model (AIA). We show that AIA severity was significantly reduced by oral FTS and F-FTS treatment compared to vehicle control treatment. FTS was as effective as the mainstay anti-rheumatic drug methotrexate, and combining the two drugs significantly increased efficacy compared to each drug alone. We also discovered that FTS therapy inhibited both the CFA-driven in vivo induction of Th17 and IL-17/IFN-γ producing "double positive" as well as the upregulation of serum levels of the Th17-associated cytokines IL-17A and IL-22. By gene microarray analysis of effector CD4 + T cells from CFA-immunized rats, re-stimulated in vitro with the mycobacterium tuberculosis heat-shock protein 65 (Bhsp65), we determined that FTS abrogated the Bhsp65-induced transcription of a large list of genes (e.g., Il17a/f, Il22, Ifng, Csf2, Lta, and Il1a). The functional enrichment bioinformatics analysis showed significant overlap with predefined gene sets related to inflammation, immune system processes and autoimmunity. In conclusion, FTS and F-FTS display broad immunomodulatory effects in AIA with inhibition of the Th17-type response to a dominant arthritogenic antigen. Hence, targeting Ras signal-transduction cascade is a potential

Evolution of the cytoskeleton

PubMed Central

Erickson, Harold P.

2009-01-01

Summary The eukaryotic cytoskeleton appears to have evolved from ancestral precursors related to prokaryotic FtsZ and MreB. FtsZ and MreB show 40−50% sequence identity across different bacterial and archaeal species. Here I suggest that this represents the limit of divergence that is consistent with maintaining their functions for cytokinesis and cell shape. Previous analyses have noted that tubulin and actin are highly conserved across eukaryotic species, but so divergent from their prokaryotic relatives as to be hardly recognizable from sequence comparisons. One suggestion for this extreme divergence of tubulin and actin is that it occurred as they evolved very different functions from FtsZ and MreB. I will present new arguments favoring this suggestion, and speculate on pathways. Moreover, the extreme conservation of tubulin and actin across eukaryotic species is not due to an intrinsic lack of variability, but is attributed to their acquisition of elaborate mechanisms for assembly dynamics and their interactions with multiple motor and binding proteins. A new structure-based sequence alignment identifies amino acids that are conserved from FtsZ to tubulins. The highly conserved amino acids are not those forming the subunit core or protofilament interface, but those involved in binding and hydrolysis of GTP. PMID:17563102

β-Lactam Antibiotics with a High Affinity for PBP2 Act Synergistically with the FtsZ-Targeting Agent TXA707 against Methicillin-Resistant Staphylococcus aureus

PubMed Central

Ferrer-González, Edgar; Kaul, Malvika; Parhi, Ajit K.; LaVoie, Edmond J.

2017-01-01

ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen that poses a significant risk to global health today. We have developed a promising new FtsZ-targeting agent (TXA707) with potent activity against MRSA isolates resistant to current standard-of-care antibiotics. We present here results that demonstrate differing extents of synergy between TXA707 and a broad range of β-lactam antibiotics (including six cephalosporins, two penicillins, and two carbapenems) against MRSA. To explore whether there is a correlation between the extent of synergy and the preferential antibacterial target of each β-lactam, we determined the binding affinities of the β-lactam antibiotics for each of the four native penicillin-binding proteins (PBPs) of S. aureus using a fluorescence anisotropy competition assay. A comparison of the resulting PBP binding affinities with our corresponding synergy results reveals that β-lactams with a high affinity for PBP2 afford the greatest degree of synergy with TXA707 against MRSA. In addition, we present fluorescence and electron microscopy studies that suggest a potential mechanism underlying the synergy between TXA707 and the β-lactam antibiotics. In this connection, our microscopy results show a disruption of septum formation in TXA707-treated MRSA cells, with a concomitant mislocalization of the PBPs from midcell to nonproductive peripheral sites. Viewed as a whole, our results indicate that PBP2-targeting β-lactam antibiotics are optimal synergistic partners with FtsZ-targeting agents for use in combination therapy of MRSA infections. PMID:28630190

Rasfonin, a novel 2-pyrone derivative, induces ras-mutated Panc-1 pancreatic tumor cell death in nude mice.

PubMed

Xiao, Z; Li, L; Li, Y; Zhou, W; Cheng, J; Liu, F; Zheng, P; Zhang, Y; Che, Y

2014-05-22

Rasfonin is a novel 2-pyrone derivative reported to induce apoptosis in ras-dependent cells. In this study, its effects on ras-mutated pancreatic cancer cells were investigated in vitro and in vivo. Two human pancreatic cancer cell lines Panc-1 (mutated K-ras) and BxPC-3 (wild-type K-ras) were selected to test the effects of rasfonin on cell proliferation, clone formation, migration and invasion in vitro. Immunoblotting was used to detect the expressions of EGFR-Ras-Raf-MEK-ERK signaling pathway proteins. Ras activity was measured using a pull-down ELISA kit and guanine exchange factor (GEF)/GTPase-activating proteins (GAP) activity was measured by [(3)H]-GDP radiometric ligand binding. For an in vivo study, CD1 nude mice bearing Panc-1 cells were treated with rasfonin or Salirasib (FTS). We found that rasfonin suppressed proliferation more strongly in Panc-1 cells (IC50=5.5 μM) than BxPC-3 cells (IC50=10 μM) in vitro. Clone formation, migration and invasion by Panc-1 cells were also reduced by rasfonin. Rasfonin had little effect on the farnesylation of Ras, but it strongly downregulated Ras activity and consequently phosphorylation of c-Raf/MEK/ERK. Further experiments indicated that rasfonin reduced Son of sevenless (Sos1) expression but did not alter GEF and GAP activities. The in vivo experiments also revealed that rasfonin (30 mg/kg) delayed the growth of xenograft tumors originating from Panc-1 cells. Tumor weight was ultimately decreased after 20 days of treatment of rasfonin. Rasfonin is a robust inhibitor of pancreatic cancers with the K-ras mutation. The reduction of Sos1 expression and the consequently depressed Ras-MAPK activity could be important in its anticancer activity.

Rasfonin, a novel 2-pyrone derivative, induces ras-mutated Panc-1 pancreatic tumor cell death in nude mice

PubMed Central

Xiao, Z; Li, L; Li, Y; Zhou, W; Cheng, J; Liu, F; Zheng, P; Zhang, Y; Che, Y

2014-01-01

Rasfonin is a novel 2-pyrone derivative reported to induce apoptosis in ras-dependent cells. In this study, its effects on ras-mutated pancreatic cancer cells were investigated in vitro and in vivo. Two human pancreatic cancer cell lines Panc-1 (mutated K-ras) and BxPC-3 (wild-type K-ras) were selected to test the effects of rasfonin on cell proliferation, clone formation, migration and invasion in vitro. Immunoblotting was used to detect the expressions of EGFR–Ras–Raf–MEK–ERK signaling pathway proteins. Ras activity was measured using a pull-down ELISA kit and guanine exchange factor (GEF)/GTPase-activating proteins (GAP) activity was measured by [3H]-GDP radiometric ligand binding. For an in vivo study, CD1 nude mice bearing Panc-1 cells were treated with rasfonin or Salirasib (FTS). We found that rasfonin suppressed proliferation more strongly in Panc-1 cells (IC50=5.5 μM) than BxPC-3 cells (IC50=10 μM) in vitro. Clone formation, migration and invasion by Panc-1 cells were also reduced by rasfonin. Rasfonin had little effect on the farnesylation of Ras, but it strongly downregulated Ras activity and consequently phosphorylation of c-Raf/MEK/ERK. Further experiments indicated that rasfonin reduced Son of sevenless (Sos1) expression but did not alter GEF and GAP activities. The in vivo experiments also revealed that rasfonin (30 mg/kg) delayed the growth of xenograft tumors originating from Panc-1 cells. Tumor weight was ultimately decreased after 20 days of treatment of rasfonin. Rasfonin is a robust inhibitor of pancreatic cancers with the K-ras mutation. The reduction of Sos1 expression and the consequently depressed Ras–MAPK activity could be important in its anticancer activity. PMID:24853419

Design, synthesis and antibacterial activity of cinnamaldehyde derivatives as inhibitors of the bacterial cell division protein FtsZ.

PubMed

Li, Xin; Sheng, Juzheng; Huang, Guihua; Ma, Ruixin; Yin, Fengxin; Song, Di; Zhao, Can; Ma, Shutao

2015-06-05

In an attempt to discover potential antibacterial agents against the increasing bacterial resistance, novel cinnamaldehyde derivatives as FtsZ inhibitors were designed, synthesized and evaluated for their antibacterial activity against nine significant pathogens using broth microdilution method, and their cell division inhibitory activity against four representative strains. In the in vitro antibacterial activity, the newly synthesized compounds generally displayed better efficacy against Staphylococcus aureus ATCC25923 than the others. In particular, compounds 3, 8 and 10 exerted superior or comparable activity to all the reference drugs. In the cell division inhibitory activity, all the compounds showed the same trend as their in vitro antibacterial activity, exhibiting better activity against S. aureus ATCC25923 than the other strains. Additionally, compounds 3, 6, 7 and 8 displayed potent cell division inhibitory activity with an MIC value of below 1 μg/mL, over 256-fold better than all the reference drugs. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Involvement of organic acids and amino acids in ameliorating Ni(II) toxicity induced cell cycle dysregulation in Caulobacter crescentus: a metabolomics analysis.

PubMed

Jain, Abhishek; Chen, Wei Ning

2018-05-01

Nickel (Ni(II)) toxicity is addressed by many different bacteria, but bacterial responses to nickel stress are still unclear. Therefore, we studied the effect of Ni(II) toxicity on cell proliferation of α-proteobacterium Caulobacter crescentus. Next, we showed the mechanism that allows C. crescentus to survive in Ni(II) stress condition. Our results revealed that the growth of C. crescentus is severely affected when the bacterium was exposed to different Ni(II) concentrations, 0.003 mM slightly affected the growth, 0.008 mM reduced the growth by 50%, and growth was completely inhibited at 0.015 mM. It was further shown that Ni(II) toxicity induced mislocalization of major regulatory proteins such as MipZ, FtsZ, ParB, and MreB, resulting in dysregulation of the cell cycle. GC-MS metabolomics analysis of Ni(II) stressed C. crescentus showed an increased level of nine important metabolites including TCA cycle intermediates and amino acids. This indicates that changes in central carbon metabolism and nitrogen metabolism are linked with the disruption of cell division process. Addition of malic acid, citric acid, alanine, proline, and glutamine to 0.015 mM Ni(II)-treated C. crescentus restored its growth. Thus, the present work shows a protective effect of these organic acids and amino acids on Ni(II) toxicity. Metabolic stimulation through the PutA/GlnA pathway, accelerated degradation of CtrA, and Ni-chelation by organic acids or amino acids are some of the possible mechanisms suggested to be involved in enhancing C. crescentus's tolerance. Our results shed light on the mechanism of increased Ni(II) tolerance in C. crescentus which may be useful in bioremediation strategies and synthetic biology applications such as the development of whole cell biosensor.

Exposure to Sub-lethal 2,4-Dichlorophenoxyacetic Acid Arrests Cell Division and Alters Cell Surface Properties in Escherichia coli.

PubMed

Bhat, Supriya V; Kamencic, Belma; Körnig, André; Shahina, Zinnat; Dahms, Tanya E S

2018-01-01

Escherichia coli is a robust, easily adaptable and culturable bacterium in vitro , and a model bacterium for studying the impact of xenobiotics in the environment. We have used correlative atomic force - laser scanning confocal microscopy (AFM-LSCM) to characterize the mechanisms of cellular response to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). One of the most extensively used herbicides world-wide, 2,4-D is known to cause hazardous effects in diverse non-target organisms. Sub-lethal concentrations of 2,4-D caused DNA damage in E. coli WM1074 during short exposure periods which increased significantly over time. In response to 2,4-D, FtsZ and FtsA relocalized within seconds, coinciding with the complete inhibition of cell septation and cell elongation. Exposure to 2,4-D also resulted in increased activation of the SOS response. Changes to cell division were accompanied by concomitant changes to surface roughness, elasticity and adhesion in a time-dependent manner. This is the first study describing the mechanistic details of 2,4-D at sub-lethal levels in bacteria. Our study suggests that 2,4-D arrests E. coli cell division within seconds after exposure by disrupting the divisome complex, facilitated by dissipation of membrane potential. Over longer exposures, 2,4-D causes filamentation as a result of an SOS response to oxidative stress induced DNA damage.

Exposure to Sub-lethal 2,4-Dichlorophenoxyacetic Acid Arrests Cell Division and Alters Cell Surface Properties in Escherichia coli

PubMed Central

Bhat, Supriya V.; Kamencic, Belma; Körnig, André; Shahina, Zinnat; Dahms, Tanya E. S.

2018-01-01

Escherichia coli is a robust, easily adaptable and culturable bacterium in vitro, and a model bacterium for studying the impact of xenobiotics in the environment. We have used correlative atomic force – laser scanning confocal microscopy (AFM-LSCM) to characterize the mechanisms of cellular response to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). One of the most extensively used herbicides world-wide, 2,4-D is known to cause hazardous effects in diverse non-target organisms. Sub-lethal concentrations of 2,4-D caused DNA damage in E. coli WM1074 during short exposure periods which increased significantly over time. In response to 2,4-D, FtsZ and FtsA relocalized within seconds, coinciding with the complete inhibition of cell septation and cell elongation. Exposure to 2,4-D also resulted in increased activation of the SOS response. Changes to cell division were accompanied by concomitant changes to surface roughness, elasticity and adhesion in a time-dependent manner. This is the first study describing the mechanistic details of 2,4-D at sub-lethal levels in bacteria. Our study suggests that 2,4-D arrests E. coli cell division within seconds after exposure by disrupting the divisome complex, facilitated by dissipation of membrane potential. Over longer exposures, 2,4-D causes filamentation as a result of an SOS response to oxidative stress induced DNA damage. PMID:29472899

Functional assignment of solute-binding proteins of ABC transporters using a fluorescence-based thermal shift assay.

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

Giulliani, S. E.; Frank, A. E.; Collart, F. R.

2008-12-08

We have used a fluorescence-based thermal shift (FTS) assay to identify amino acids that bind to solute-binding proteins in the bacterial ABC transporter family. The assay was validated with a set of six proteins with known binding specificity and was consistently able to map proteins with their known binding ligands. The assay also identified additional candidate binding ligands for several of the amino acid-binding proteins in the validation set. We extended this approach to additional targets and demonstrated the ability of the FTS assay to unambiguously identify preferential binding for several homologues of amino acid-binding proteins with known specificity andmore » to functionally annotate proteins of unknown binding specificity. The assay is implemented in a microwell plate format and provides a rapid approach to validate an anticipated function or to screen proteins of unknown function. The ABC-type transporter family is ubiquitous and transports a variety of biological compounds, but the current annotation of the ligand-binding proteins is limited to mostly generic descriptions of function. The results illustrate the feasibility of the FTS assay to improve the functional annotation of binding proteins associated with ABC-type transporters and suggest this approach that can also be extended to other protein families.« less

Reduced Levels of Chloroplast FtsH Protein in Tobacco Mosaic Virus–Infected Tobacco Leaves Accelerate the Hypersensitive Reaction

PubMed Central

Seo, Shigemi; Okamoto, Masaji; Iwai, Takayoshi; Iwano, Megumi; Fukui, Kiichi; Isogai, Akira; Nakajima, Nobuyoshi; Ohashi, Yuko

2000-01-01

In tobacco cultivars resistant to tobacco mosaic virus (TMV), infection results in the death of the infected cells accompanying the formation of necrotic lesions. To identify the genes involved in this hypersensitive reaction, we isolated the cDNA of tobacco DS9, the transcript of which decreases before the appearance of necrotic lesions. The DS9 gene encodes a chloroplastic homolog of bacterial FtsH protein, which serves to maintain quality control of some cytoplasmic and membrane proteins. A large quantity of DS9 protein was found in healthy leaves, whereas the quantity of DS9 protein in infected leaves decreased before the lesions appeared. In transgenic tobacco plants containing less and more DS9 protein than wild-type plants, the necrotic lesions induced by TMV were smaller and larger, respectively, than those on wild-type plants. These results suggest that a decrease in the level of DS9 protein in TMV-infected cells, resulting in a subsequent loss of function of the chloroplasts, accelerates the hypersensitive reaction. PMID:10852937

Contribution of the Pmra Promoter to Expression of Genes in the Escherichia coli mra Cluster of Cell Envelope Biosynthesis and Cell Division Genes

PubMed Central

Mengin-Lecreulx, Dominique; Ayala, Juan; Bouhss, Ahmed; van Heijenoort, Jean; Parquet, Claudine; Hara, Hiroshi

1998-01-01

Recently, a promoter for the essential gene ftsI, which encodes penicillin-binding protein 3 of Escherichia coli, was precisely localized 1.9 kb upstream from this gene, at the beginning of the mra cluster of cell division and cell envelope biosynthesis genes (H. Hara, S. Yasuda, K. Horiuchi, and J. T. Park, J. Bacteriol. 179:5802–5811, 1997). Disruption of this promoter (Pmra) on the chromosome and its replacement by the lac promoter (Pmra::Plac) led to isopropyl-β-d-thiogalactopyranoside (IPTG)-dependent cells that lysed in the absence of inducer, a defect which was complemented only when the whole region from Pmra to ftsW, the fifth gene downstream from ftsI, was provided in trans on a plasmid. In the present work, the levels of various proteins involved in peptidoglycan synthesis and cell division were precisely determined in cells in which Pmra::Plac promoter expression was repressed or fully induced. It was confirmed that the Pmra promoter is required for expression of the first nine genes of the mra cluster: mraZ (orfC), mraW (orfB), ftsL (mraR), ftsI, murE, murF, mraY, murD, and ftsW. Interestingly, three- to sixfold-decreased levels of MurG and MurC enzymes were observed in uninduced Pmra::Plac cells. This was correlated with an accumulation of the nucleotide precursors UDP–N-acetylglucosamine and UDP–N-acetylmuramic acid, substrates of these enzymes, and with a depletion of the pool of UDP–N-acetylmuramyl pentapeptide, resulting in decreased cell wall peptidoglycan synthesis. Moreover, the expression of ftsZ, the penultimate gene from this cluster, was significantly reduced when Pmra expression was repressed. It was concluded that the transcription of the genes located downstream from ftsW in the mra cluster, from murG to ftsZ, is also mainly (but not exclusively) dependent on the Pmra promoter. PMID:9721276

The cell wall and cell division gene cluster in the Mra operon of Pseudomonas aeruginosa: cloning, production, and purification of active enzymes.

PubMed

Azzolina, B A; Yuan, X; Anderson, M S; El-Sherbeini, M

2001-04-01

We have cloned the Pseudomonas aeruginosa cell wall biosynthesis and cell division gene cluster that corresponds to the mra operon in the 2-min region of the Escherichia coli chromosome. The organization of the two chromosomal regions in P. aeruginosa and E. coli is remarkably similar with the following gene order: pbp3/pbpB, murE, murF, mraY, murD, ftsW, murG, murC, ddlB, ftsQ, ftsA, ftsZ, and envA/LpxC. All of the above P. aeruginosa genes are transcribed from the same strand of DNA with very small, if any, intragenic regions, indicating that these genes may constitute a single operon. All five amino acid ligases, MurC, MurD, MurE, MurF, and DdlB, in addition to MurG and MraY were cloned in expression vectors. The four recombinant P. aeruginosa Mur ligases, MurC, MurD, MurE, and MurF were overproduced in E. coli and purified as active enzymes. Copyright 2001 Academic Press.

Recommended fine positioning test for the Development Test Flight (DTF-1) of the NASA Flight Telerobotic Servicer (FTS)

NASA Technical Reports Server (NTRS)

Dagalakis, N.; Wavering, A. J.; Spidaliere, P.

1991-01-01

Test procedures are proposed for the NASA DTF (Development Test Flight)-1 positioning tests of the FTS (Flight Telerobotic Servicer). The unique problems associated with the DTF-1 mission are discussed, standard robot performance tests and terminology are reviewed and a very detailed description of flight-like testing and analysis is presented. The major technical problem associated with DTF-1 is that only one position sensor can be used, which will be fixed at one location, with a working volume which is probably smaller than some of the robot errors to be measured. Radiation heating of the arm and the sensor could also cause distortions that would interfere with the test. Two robot performance testing committees have established standard testing procedures relevant to the DTF-1. Due to the technical problems associated with DTF-1, these procedures cannot be applied directly. These standard tests call for the use of several test positions at specific locations. Only one position, that of the position sensor, can be used by DTF-1. Off-line programming accuracy might be impossible to measure and in that case it will have to be replaced by forward kinetics accuracy.

ACE-FTS Observation of a Young Biomass Burning Plume: First Reported Measurements of C2H4, C3H6O, H2CO and PAN by Infrared Occultation from Space

NASA Technical Reports Server (NTRS)

Coheur, Pierre-Francois; Herbin, Herve; Clerbaux, Cathy; Hurtmans, Daniel; Wespes, Catherine; Carleer, Michel; Turquety, Solene; Rinsland, Curtis P.; Remedios, John; Hauglustaine, Didier;

The distinctive cell division interactome of Neisseria gonorrhoeae.

PubMed

Zou, Yinan; Li, Yan; Dillon, Jo-Anne R

2017-12-12

Bacterial cell division is an essential process driven by the formation of a Z-ring structure, as a cytoskeletal scaffold at the mid-cell, followed by the recruitment of various proteins which form the divisome. The cell division interactome reflects the complement of different interactions between all divisome proteins. To date, only two cell division interactomes have been characterized, in Escherichia coli and in Streptococcus pneumoniae. The cell divison proteins encoded by Neisseria gonorrhoeae include FtsZ, FtsA, ZipA, FtsK, FtsQ, FtsI, FtsW, and FtsN. The purpose of the present study was to characterize the cell division interactome of N. gonorrhoeae using several different methods to identify protein-protein interactions. We also characterized the specific subdomains of FtsA implicated in interactions with FtsZ, FtsQ, FtsN and FtsW. Using a combination of bacterial two-hybrid (B2H), glutathione S-transferase (GST) pull-down assays, and surface plasmon resonance (SPR), nine interactions were observed among the eight gonococcal cell division proteins tested. ZipA did not interact with any other cell division proteins. Comparisons of the N. gonorrhoeae cell division interactome with the published interactomes from E. coli and S. pneumoniae indicated that FtsA-FtsZ and FtsZ-FtsK interactions were common to all three species. FtsA-FtsW and FtsK-FtsN interactions were only present in N. gonorrhoeae. The 2A and 2B subdomains of FtsA Ng were involved in interactions with FtsQ, FtsZ, and FtsN, and the 2A subdomain was involved in interaction with FtsW. Results from this research indicate that N. gonorrhoeae has a distinctive cell division interactome as compared with other microorganisms.

Nearly arc-length tool path generation and tool radius compensation algorithm research in FTS turning

NASA Astrophysics Data System (ADS)

Zhao, Minghui; Zhao, Xuesen; Li, Zengqiang; Sun, Tao

2014-08-01

In the non-rotational symmetrical microstrcture surfaces generation using turning method with Fast Tool Servo(FTS), non-uniform distribution of the interpolation data points will lead to long processing cycle and poor surface quality. To improve this situation, nearly arc-length tool path generation algorithm is proposed, which generates tool tip trajectory points in nearly arc-length instead of the traditional interpolation rule of equal angle and adds tool radius compensation. All the interpolation points are equidistant in radial distribution because of the constant feeding speed in X slider, the high frequency tool radius compensation components are in both X direction and Z direction, which makes X slider difficult to follow the input orders due to its large mass. Newton iterative method is used to calculate the neighboring contour tangent point coordinate value with the interpolation point X position as initial value, in this way, the new Z coordinate value is gotten, and the high frequency motion components in X direction is decomposed into Z direction. Taking a typical microstructure with 4μm PV value for test, which is mixed with two 70μm wave length sine-waves, the max profile error at the angle of fifteen is less than 0.01μm turning by a diamond tool with big radius of 80μm. The sinusoidal grid is machined on a ultra-precision lathe succesfully, the wavelength is 70.2278μm the Ra value is 22.81nm evaluated by data points generated by filtering out the first five harmonics.

New and improved infra-red absorption cross sections and ACE-FTS retrievals of carbon tetrachloride (CCl4)

NASA Astrophysics Data System (ADS)

Harrison, Jeremy J.; Boone, Christopher D.; Bernath, Peter F.

2017-01-01

Carbon tetrachloride (CCl4) is one of the species regulated by the Montreal Protocol on account of its ability to deplete stratospheric ozone. As such, the inconsistency between observations of its abundance and estimated sources and sinks is an important problem requiring urgent attention (Carpenter et al., 2014) [5]. Satellite remote-sensing has a role to play, particularly limb sounders which can provide vertical profiles into the stratosphere and therefore validate stratospheric loss rates in atmospheric models. This work is in two parts. The first describes new and improved high-resolution infra-red absorption cross sections of carbon tetrachloride/dry synthetic air over the spectral range 700-860 cm-1 for a range of temperatures and pressures (7.5-760 Torr and 208-296 K) appropriate for atmospheric conditions. This new cross-section dataset improves upon the one currently available in the HITRAN and GEISA databases. The second describes a new, preliminary ACE-FTS carbon tetrachloride retrieval that improves upon the v3.0/v3.5 data products, which are biased high by up to 20-30% relative to ground measurements. Making use of the new spectroscopic data, this retrieval also improves the microwindow selection, contains additional interfering species, and utilises a new instrumental lineshape; it will form the basis for the upcoming v4.0 CCl4 data product.

Isolation and Characterization of Ftsz Genes in Cassava.

PubMed

Geng, Meng-Ting; Min, Yi; Yao, Yuan; Chen, Xia; Fan, Jie; Yuan, Shuai; Wang, Lei; Sun, Chong; Zhang, Fan; Shang, Lu; Wang, Yun-Lin; Li, Rui-Mei; Fu, Shao-Ping; Duan, Rui-Jun; Liu, Jiao; Hu, Xin-Wen; Guo, Jian-Chun

2017-12-15

The filamenting temperature-sensitive Z proteins (FtsZs) play an important role in plastid division. In this study, three FtsZ genes were isolated from the cassava genome, and named MeFtsZ1, MeFtsZ2-1, and MeFtsZ2-2, respectively. Based on phylogeny, the MeFtsZs were classified into two groups (FtsZ1 and FtsZ2). MeFtsZ1 with a putative signal peptide at N-terminal, has six exons, and is classed to FtsZ1 clade. MeFtsZ2-1 and MeFtsZ2-2 without a putative signal peptide, have seven exons, and are classed to FtsZ2 clade. Subcellular localization found that all the three MeFtsZs could locate in chloroplasts and form a ring in chloroplastids. Structure analysis found that all MeFtsZ proteins contain a conserved guanosine triphosphatase (GTPase) domain in favor of generate contractile force for cassava plastid division. The expression profiles of MeFtsZ genes by quantitative reverse transcription-PCR (qRT-PCR) analysis in photosynthetic and non-photosynthetic tissues found that all of the MeFtsZ genes had higher expression levels in photosynthetic tissues, especially in younger leaves, and lower expression levels in the non-photosynthetic tissues. During cassava storage root development, the expressions of MeFtsZ2-1 and MeFtsZ2-2 were comparatively higher than MeFtsZ1. The transformed Arabidopsis of MeFtsZ2-1 and MeFtsZ2-2 contained abnormally shape, fewer number, and larger volume chloroplasts. Phytohormones were involved in regulating the expressions of MeFtsZ genes. Therefore, we deduced that all of the MeFtsZs play an important role in chloroplast division, and that MeFtsZ 2 (2-1, 2-2) might be involved in amyloplast division and regulated by phytohormones during cassava storage root development.

A murC gene from coryneform bacteria.

PubMed

Wachi, M; Wijayarathna, C D; Teraoka, H; Nagai, K

1999-02-01

The upstream flanking region of the ftsQ and ftsZ genes of Brevibacterium flavum MJ233, which belongs to the coryneform bacteria, was amplified by the inverse polymerase chain reaction method and cloned in Escherichia coli. Complementation analysis of E. coli mutant with a defective cell-wall synthesis mechanism with the cloned fragment and its DNA sequencing indicated the presence of the murC gene, encoding UDP-N-acetylmuramate:L-alanine ligase involved in peptidoglycan synthesis, just upstream from the ftsQ gene. The B. flavum murC gene could encode a protein of 486 amino acid residues with a calculated molecular mass of 51 198 Da. A 50-kDa protein was synthesized by the B. flavum murC gene in an in vitro transcription/translation system using E. coli S30 lysate. These results indicate that the genes responsible for cell-wall synthesis and cell division are located as a cluster in B. flavum similar to the E. coli mra region.

GOSAT/TANSO-FTS Measurement of Volcanic and Geothermal CO2 Emissions

NASA Astrophysics Data System (ADS)

Schwandner, Florian M.; Carn, Simon A.; Newhall, Christopher G.

2010-05-01

volcanic CO2 anomalies using GOSAT and correlation with Aura/OMI, AIRS, and ASTER determined SO2 fluxes and ground based monitoring of CO2 and other geophysical and geochemical parameters. This will provide the ground work for future higher spatial resolution satellite missions. This is a joint effort from two GOSAT-IBUKI data application projects: "Satellite-Borne Quantification of Carbon Dioxide Emissions from Volcanoes and Geothermal Areas" (PI Schwandner), and "Application of GOSAT/TANSO-FTS to the Measurement of Volcanic CO2 Emissions" (PI Carn).

Preparation of flower-like TiO{sub 2} sphere/reduced graphene oxide composites for photocatalytic degradation of organic pollutants

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

Kim, Tae-Woong; Park, Mira; Kim, Hak Yong

In this study, novel flower-like TiO{sub 2} sphere (FTS)/reduced graphene oxide (rGO) composites (FTS-G) were synthesized via a hydrothermal method. The photocatalytic performance of the FTS-G composites was evaluated through the photodegradation of rhodamine B (Rh B) and trichloroethylene (TCE) under simulated solar light irradiation. The rGO to FTS ratio in the composites significantly affected photocatalytic activity. The photocatalytic activities of FTS-Gs in the degradation of Rh B and TCE were superior to that of pure FTS. Of all the FTS-G composites tested, FTS-G with 1 wt% rGO (FTS-G-1) had the greatest photocatalytic activity, while FTS-G composites with rGO contentsmore » over 1 wt% had lower photocatalytic activities. Additionally, it is expected that the synthesis of FTS with a high specific surface area and well-developed pore structure and simultaneous conversion of GO to graphene-like rGO without the use of strong reducing agents could be a promising strategy to prepare other carbon-based flower-like TiO{sub 2} sphere composite photocatalysts. - Graphical abstract: Schematic illustration of high photocatalytic activity for FTS-G composites. Display Omitted.« less

Preparation of flower-like TiO2 sphere/reduced graphene oxide composites for photocatalytic degradation of organic pollutants

NASA Astrophysics Data System (ADS)

Kim, Tae-Woong; Park, Mira; Kim, Hak Yong; Park, Soo-Jin

2016-07-01

In this study, novel flower-like TiO2 sphere (FTS)/reduced graphene oxide (rGO) composites (FTS-G) were synthesized via a hydrothermal method. The photocatalytic performance of the FTS-G composites was evaluated through the photodegradation of rhodamine B (Rh B) and trichloroethylene (TCE) under simulated solar light irradiation. The rGO to FTS ratio in the composites significantly affected photocatalytic activity. The photocatalytic activities of FTS-Gs in the degradation of Rh B and TCE were superior to that of pure FTS. Of all the FTS-G composites tested, FTS-G with 1 wt% rGO (FTS-G-1) had the greatest photocatalytic activity, while FTS-G composites with rGO contents over 1 wt% had lower photocatalytic activities. Additionally, it is expected that the synthesis of FTS with a high specific surface area and well-developed pore structure and simultaneous conversion of GO to graphene-like rGO without the use of strong reducing agents could be a promising strategy to prepare other carbon-based flower-like TiO2 sphere composite photocatalysts.

Thymic hormone-containing cells. Characterization and localization of serum thymic factor in young mouse thymus studied by monoclonal antibodies

PubMed Central

1982-01-01

The characterization and distribution of cells containing the serum thymic factor (FTS) in the thymus of young mice was studied by immunofluorescence using monoclonal anti-FTS antibodies. FTS+ cells were distributed throughout the thymic parenchyma but were more frequent in the medullary region than in the cortex. FTS-containing cells presented a stellate or globular aspect, and some of them exhibited fluorescent cytoplasmic granules. The epithelial nature of FTS+ cells was confirmed by double-labeling experiments using an anti- keratin antiserum (as an epithelial cell marker). Nevertheless, only a minority of keratin-positive epithelial reticular cells contained FTS. All controls, including the incubation of sections from nonthymic tissues with the anti-FTS antibodies, were negative. Taken together, these results confirm the exclusive localization of FTS-containing cells within the mouse thymus. PMID:7047671

Evaluating vertical concentration profile of carbon source released from slow-releasing carbon source tablets and in situ biological nitrate denitrification activity

NASA Astrophysics Data System (ADS)

Yeum, Y.; HAN, K.; Yoon, J.; Lee, J. H.; Song, K.; Kang, J. H.; Park, C. W.; Kwon, S.; Kim, Y.

2017-12-01

Slow-releasing carbon source tablets were manufactured during the design of a small-scale in situ biological denitrification system to reduce high-strength nitrate (> 30 mg N/L) from a point source such as livestock complexes. Two types of slow-releasing tablets, precipitating tablet (PT, apparent density of 2.0 g/mL) and floating tablet (FT), were prepared to achieve a vertically even distribution of carbon source (CS) in a well and an aquifer. Hydroxypropyl methylcellulose (HPMC) was used to control the release rate, and microcrystalline cellulose pH 101 (MCC 101) was added as a binder. The #8 sand was used as a precipitation agent for the PTs, and the floating agents for the FTs were calcium carbonate and citric acid. FTs floated within 30 min. and remained in water because of the buoyance from carbon dioxide, which formed during the acid-base reaction between citric acid and calcium carbonate. The longevities of PTs with 300 mg of HPMC and FTs with 400 mg of HPMC were 25.4 days and 37.3 days, respectively. We assessed vertical CS profile in a continuous flowing physical aquifer model (release test, RT) and its efficiency on biological nitrate denitrification (denitrification test, DT). During the RT, PTs, FTs and a tracer (as 1 mg rhodamine B/L) were initially injected into a well of physical aquifer model (PAM). Concentrations of CS and the tracer were monitored along the streamline in the PAM to evaluate vertical profile of CS. During the DT, the same experiment was performed as RT, except continuous injection of solution containing 30 mg N/L into the PAM to evaluate biological denitrification activity. As a result of RT, temporal profiles of CS were similar at 3 different depths of monitoring wells. These results suggest that simultaneous addition of PT and FT be suitable for achieving a vertically even distribution of the CS in the injection well and an aquifer. In DT, similar profile of CS was detected in the injection well, and nitrate was biologically

Sodium chloride-induced filamentation and alternative gene expression of fts, murZ, and gnd in Listeria monocytogenes 08-5923 on vacuum-packaged ham.

PubMed

Liu, Xiaoji; Miller, Petr; Basu, Urmila; McMullen, Lynn M

2014-11-01

The aim of this study was to examine the filament formation and differential gene expression of Listeria monocytogenes 08-5923 grown on refrigerated vacuum-packaged ham products with various NaCl concentrations. Filament formation of L. monocytogenes was observed on ham products with 1.35% and 2.35% NaCl, which was monitored using flow cytometry by measuring forward light scatter. Quantitative real-time PCR was used to study the differential expression of genes in filamented cells of L. monocytogenes grown on hams following 2 or 3 months of storage at 4 °C. The genes involved in cell division (ftsX/lmo2506), cell wall synthesis (murZ/lmo2552), and NADPH production (gnd/lmo1376) were significantly downregulated in filamented cells of L. monocytogenes grown on ham with 2.35% NaCl stored at 4 °C. To our knowledge, this study reports the first evidence of filament formation of Listeria grown on meat products, which could impact the food safety risk and tolerance levels of L. monocytogenes set by regulatory agencies. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Validation of XCO2 derived from SWIR of GOSAT TANSO-FTS with aircraft measurement data

NASA Astrophysics Data System (ADS)

Inoue, M.; Morino, I.; Uchino, O.; Miyamoto, Y.; Yoshida, Y.; Yokota, T.; Machida, T.; Sawa, Y.; Matsueda, H.; Sweeney, C.; Tans, P. P.; Andrews, A. E.; Patra, P. K.

2011-12-01

Column-averaged mixing ratios of carbon dioxide (XCO2) are retrieved from the Short-Wavelength InfraRed (SWIR) spectrum of Thermal And Near-infrared Sensor for carbon Observation - Fourier Transform Spectrometer (TANSO-FTS) onboard the Greenhouse gases Observing SATellite (GOSAT). They are compared with the aircraft data measured by the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, National Oceanic and Atmospheric Administration (NOAA), and National Institute for Environmental Studies (NIES). Because limited aircraft measurement was conducted within a few hours of the GOSAT overpass time, we prepared temporally interpolated aircraft-based XCO2 data by fitting with the function that contains yearly trend and annual/semiannual sinusoidal variations to compare with GOSAT XCO2. As for the GOSAT XCO2 data, those retrieved within ±2 degrees or ±5 degrees latitude/longitude box centered at each observation site were used. In order to compare the aircraft data with the satellite data, the GOSAT column averaging kernels (CAK) should be taken into account to calculate the aircraft-based XCO2. However, it is hard to apply GOSAT CAK with temporally interpolated aircraft data. Therefore, we evaluated the GOSAT CAK impact on the aircraft-based XCO2 calculation by using CONTRAIL data over Narita (35.8N, 140.4E) where the maximum temporally match-upped data are available. The difference in the aircraft-based XCO2 with and without GOSAT CAK is lower by approximately 0.3 ppm. Here, we made a comparison between GOSAT XCO2 and aircraft-based XCO2 without GOSAT CAK. Although GOSAT data are underestimated by approximately 7-9 ppm for comparison in every site, there is a good correlation between both datasets in some sites, such as high-latitude regions of North America, Europe, Siberia, and ocean regions. A direct comparison between GOSAT and aircraft XCO2 at all observation sites shows that GOSAT SWIR XCO2 is biased low by about 8 ppm.

A portable FTS measurements during GOSAT and OCO-2 joint campaign in Western US 2017

NASA Astrophysics Data System (ADS)

Shiomi, K.; Kikuchi, N.; Kuze, A.; Hashimoto, M.; Suto, H.; Kataoka, F.; Kasai, K.; Arai, T.; Oshio, H.; Ohyama, H.; Morino, I.; Hori, A.; Hedelius, J.; Parker, H. A.; Roehl, C. M.; Wennberg, P. O.; Leifer, I.; Iraci, L. T.; Bruegge, C. J.; Schwandner, F. M.; Osterman, G. B.; Crisp, D.

2017-12-01

The column-average dry air mole fractions of carbon dioxide (XCO2), methane (XCH4) and carbon monoxide (XCO) were measured from the surface using direct sunlight at near-IR wavelengths. Simultaneous detection of CO is helpful to characterize CO2 source type. We measured XCO along with XCO2 and XCH4 using an upgraded portable Fourier transform spectrometer (FTS), EM27/SUN, in western US field experiments at 1) Caltech and JPL, in Pasadena, a northern Los Angeles suburb, 2) Railroad Valley (RRV), a desert playa in Nevada, and 3) Salton Sea, a terminal high-salinity lake in southern California's Imperial Valley. These measurements were conducted during the GOSAT/OCO-2 joint campaign in the early summer of 2017. Before and after US shipments, the JAXA EM27 was compared with the NIES EM27 and Tsukuba TCCON station to quantify the measurement bias and to identify any unanticipated changes. After US shipment, the JAXA EM27 was compared with the Caltech EM27 and the Caltech TCCON station with the NASA-Dryden TCCON station, which is now located at JPL for OCO-3 pre-flight test comparisons. At RRV, we obtained not only the EM27 data but also atmospheric profile of pressure, temperature and humidity by radiosonde and aerosol optical thickness (AOT) by Microtops. Then, we deployed the EM27 on the south side of the Salton Sea, where agriculture, active volcanism and geothermal power plants might produce CO2 and CH4 as sources. A large CO enhancement originating from wildfires was serendipitously measured in conjunction with a large AOT measured by the Microtops. The JAXA EM27 measurements at Pasadena, RRV and Salton Sea were taken in conjunction with GOSAT and OCO-2 overpass targets and are being used to assess the value of the EM27 as a portable transfer standard for validating space based measurements of greenhouse gases.

Studying the Immunomodulatory Effects of Small Molecule Ras Inhibitors in Animal Models of Rheumatoid Arthritis

DTIC Science & Technology

2017-10-01

methotrexate (MTX) provides a superior protective effect compared to monotherapy. (iii) In the AIA model the FTS derivative, F-FTS, showed higher...therapeutic efficacy compared to FTS. (iv) The functional genomics studies showed that FTS therapy inhibits the in vivo TH17 immune response. (v) FTS semi... Description shall include pertinent data and graphs in sufficient detail to explain any significant results achieved. A succinct description of the

The space station freedom flight telerobotic servicer. The design and evolution of a dexterous space robot

NASA Astrophysics Data System (ADS)

McCain, Harry G.; Andary, James F.; Hewitt, Dennis R.; Haley, Dennis C.

The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the general nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper.

The Space Station Freedom Flight Telerobotic Servicer: the design and evolution of a dexterous space robot.

PubMed

McCain, H G; Andary, J F; Hewitt, D R; Haley, D C

1991-01-01

The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station) Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper.

The Space Station Freedom Flight Telerobotic Servicer: the design and evolution of a dexterous space robot

NASA Technical Reports Server (NTRS)

McCain, H. G.; Andary, J. F.; Hewitt, D. R.; Haley, D. C.

1991-01-01

The Flight Telerobotic Servicer (FTS) Project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station) Freedom (SSF). The FTS will provide a telerobotic capability to the Freedom Station in the early assembly phases of the program and will be employed for assembly, maintenance, and inspection applications throughout the lifetime of the space station. Appropriately configured elements of the FTS will also be employed for robotic manipulation in remote satellite servicing applications and possibly the Lunar/Mars Program. In mid-1989, the FTS entered the flight system design and implementation phase (Phase C/D) of development with the signing of the FTS prime contract with Martin Marietta Astronautics Group in Denver, Colorado. The basic FTS design is now established and can be reported on in some detail. This paper will describe the FTS flight system design and the rationale for the specific design approaches and component selections. The current state of space technology and the nature of the FTS task dictate that the FTS be designed with sophisticated teleoperation capabilities for its initial primary operating mode. However, there are technologies, such as advanced computer vision and autonomous planning techniques currently in research and advanced development phases which would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Therefore, a specific requirement on the initial FTS design is that it has the capability to evolve as new technology becomes available. This paper will describe the FTS design approach for evolution to more autonomous capabilities. Some specific task applications of the FTS and partial automation approaches of these tasks will also be discussed in this paper.

Two-step membrane binding by the bacterial SRP receptor enable efficient and accurate Co-translational protein targeting.

PubMed

Hwang Fu, Yu-Hsien; Huang, William Y C; Shen, Kuang; Groves, Jay T; Miller, Thomas; Shan, Shu-Ou

2017-07-28

The signal recognition particle (SRP) delivers ~30% of the proteome to the eukaryotic endoplasmic reticulum, or the bacterial plasma membrane. The precise mechanism by which the bacterial SRP receptor, FtsY, interacts with and is regulated at the target membrane remain unclear. Here, quantitative analysis of FtsY-lipid interactions at single-molecule resolution revealed a two-step mechanism in which FtsY initially contacts membrane via a Dynamic mode, followed by an SRP-induced conformational transition to a Stable mode that activates FtsY for downstream steps. Importantly, mutational analyses revealed extensive auto-inhibitory mechanisms that prevent free FtsY from engaging membrane in the Stable mode; an engineered FtsY pre-organized into the Stable mode led to indiscriminate targeting in vitro and disrupted FtsY function in vivo. Our results show that the two-step lipid-binding mechanism uncouples the membrane association of FtsY from its conformational activation, thus optimizing the balance between the efficiency and fidelity of co-translational protein targeting.

Preliminary assignments of 2 ν 3 - ν 4 hot band of 12 CH 4 in the 2 μm transparency window from long-path FTS spectra

NASA Astrophysics Data System (ADS)

Nikitin, A. V.; Daumont, L.; Thomas, X.; Régalia, L.; Rey, M.; Tyuterev, Vl. G.; Brown, L. R.

2011-07-01

New measurements and assignments for the rovibrational transitions of the hot band 2 v3- v4 of 12CH 4 are reported from 4600 to 4880 cm -1 and refer to lower part of the 2 μm methane transparency window. Three long-path spectra were recorded with a Fourier transform spectrometer (FTS) in Reims using an L = 1603 m absorption path length at 1, 7, 34 h Pa for the natural samples of CH 4; a spectrum of enriched 13CH 4 was also used. Assignments were made for 196 lines of 2 v3(F 2,E)- v4. These transitions had an integrated intensity of 5 × 10 -24 cm/molecule at 296 K and improved the overall description of absorption in the 2.1 μm region. The empirical upper state levels of these assignments belong to Tetradecad (4800-6200 cm -1). The new analysis provided much better accuracies of badly blended positions of 2 v3(F 2)-ground state manifolds at 1.66 μm.

Previous cognitive impairment and failure to thrive syndrome in patients who died in a geriatric convalescence hospitalization unit.

PubMed

Aguilera, A; Pi-Figuews, M; Arellano, M; Torres, R M; García-Caselles, M P; Robles, M J; Miralles, R; Cervera, A M

2004-01-01

Cognitive impairment and depression are commonly associated with poor outcomes in geriatric patients. Both are part of the "failure to thrive syndrome" (FTS), that is a combined group of symptoms as a result from progressive functional, mental and nutritional impairment status in older patients. This paper was aimed at evaluating the presence of FTS in the patients who died in a geriatric convalescence unit (GCU) (intermediate care facility) and comparing the characteristics of patients with primary FTS (not associated with an evident identifiable disease) and secondary FTS (associated with an evident identifiable disease). Finally, we wanted to analyze if the presence of cognitive impairment before admission was associated with the type of FTS. We analyzed 78 patients retrospectively. The presence of the next three conditions was necessary to define the FTS: (i) Impaired functional status and malnutrition. (ii) Cognitive impairment and/or depression. (iii) Absence of improvement, after a specific geriatric intervention program during the hospitalization. Functional status for basic and instrumental activities of daily living (ADL and IADL) and the presence of symptoms cognitive impairment before admission were evaluated. Of the 78 analyzed patients, there were 30 (38.4%) with symptoms of FTS. Seventeen of them (56.6%) had a secondary FTS and 13 (43.3%) a primary one. This last group of patients had a significantly higher mean age (84.7 +/- 5.8 vs. 78.6 +/- 7.2; p < 0.02) and before admission they were significantly more dependent for ADL: 10 patients (76.9%) vs. 7 (41.0%) chi2 = 3.833, p < 0.05. A higher proportion of subjects with cognitive impairment before admission was found in the group of patients with primary FTS, than in those secondary FTS, although this difference did not reach statistical significance. Patients with primary FTS seem to be older and more dependent for ADL before admission, than those with secondary FTS.

A New Baseline for the Inertial Navigation Strapdown Simulator Program. Volume 2. Analytical Development

DTIC Science & Technology

1978-07-01

l)ground volocity-es ft/S VEL(2) ground velocity-north Wt/ VEL (3)’ ground velocity-up ft/S 4 .ASM) ft/s2 ABM (2 specific force a f,/.2 hB(3) -ft/S 2...Inertial Navigation Sytem Standardized Software _______________ Reej-977, C.S. Draper Lab., Softwre Deelopent, Fitnal Technical Report,, Cambridge

Effects of Lewis acidity of metal oxide promoters on the activity and selectivity of Co-based Fischer–Tropsch synthesis catalysts

DOE PAGES

Johnson, Gregory R.; Bell, Alexis T.

2016-03-31

Metal oxides of Ce, Gd, La, Mn, and Zr were investigated as promoters for improving the activity and selectivity of Co-based FTS catalysts. The extent to which these promoters decrease the selectivity toward CH 4 and increase the selectivity toward C 5+ hydrocarbons was found to depend on both the loading and the composition of the oxide promoter. Elemental mapping by STEM-EDS revealed that the propensity for a given metal oxide to associate with Co affects the sensitivity of the product distribution to changes in promoter loading. For all promoters, a sufficiently high loading resulted in the product distributions becomingmore » insensitive to further increases in promoter loading, very likely due to the formation of a half monolayer of promoter oxide over the Co surface. Simulations suggest that the fraction of Co active sites that are adjacent to the promoter moieties approaches unity at this degree of coverage. The oxidation state of the promoter metal cation under reaction conditions, determined by in situ XANES measurements, was used to calculate relative Lewis acidity of the promoter metal cation. We found a strong positive correlation between the C 5+ product selectivity and the Lewis acidity of the promoter metal cations, suggesting that the promotional effects are a consequence of Lewis acid-base interactions between the reaction intermediates and the promoter metal cations. Rate data obtained at different pressures were used to estimate the apparent rate coefficient and the CO adsorption constant appearing in the Langmuir-Hinshelwood expression that describes the CO consumption kinetics for both unpromoted and the metal oxide-promoted catalysts. Both parameters exhibited positive correlations with the promoter Lewis acidity. Our results are consistent with the hypothesis that the metal cations of the promoter act as Lewis acids that interact with the O atom of adsorbed CO to facilitate CO adsorption and dissociation.« less

The role of social cognitive theory in farm-to-school-related activities: implications for child nutrition.

PubMed

Berlin, Linda; Norris, Kimberly; Kolodinsky, Jane; Nelson, Abbie

2013-08-01

Farm-to-school (FTS) programs are gaining attention for many reasons, one of which is the recognition that they could help stem the increase in childhood overweight and obesity. Most FTS programs that have been evaluated have increased students' selection or intake of fruits and vegetables following the incorporation of FTS components. However, the wide range of activities that are typically part of FTS programs make it difficult to pinpoint which components have the greatest potential to improve students' health behaviors. Within the field of nutrition education, theory-based interventions that target the key underlying factors influencing health behavior offer the most promise. We review existing research on dietary health impacts and implications of 3 key FTS-related activities and explore the component activities of FTS in terms of their potential to address the key constructs of social cognitive theory (SCT)--which is a current best practice in the field of nutrition--suggesting that FTS programs incorporating a diverse set of activities appear to be most promising. We find that components of FTS programs incorporate many of the key theoretical constructs in SCT, and show that FTS programs have great potential to facilitate movement toward desired dietary changes. However, it is unlikely that a set of activities in any one current FTS program addresses multiple constructs of the theory in a systematic manner. More intentional inclusion of diverse activities would likely be beneficial. Future research can test these assertions. © 2013, American School Health Association.

Validation of GOSAT/TANSO-FTS TIR V01.00 CO2 and CH4 products

NASA Astrophysics Data System (ADS)

Saitoh, N.; Kimoto, S.; Sugimura, R.; Imasu, R.; Kawakami, S.; Shiomi, K.; Machida, T.; Sawa, Y.; Matsuda, H.

2014-12-01

Greenhouse Gases Observing Satellite (GOSAT) has been making observations continuously for more than five years since its launch on 23 January 2009. Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) on board the GOSAT simultaneously observes column abundances and profiles of CO2 and CH4 in the same field of view, from the shortwave infrared (SWIR) and thermal infrared (TIR) bands, respectively. We have just released the latest TIR CO2 and CH4 products, V01.00, to registered researchers. To validate the data quality of the V01.00 TIR CO2 product, we compared the TIR data with CO2 data obtained by Continuous CO2 Measuring Equipment (CME) on board JAL aircraft in Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) project. The aircraft CO2 data obtained during the level flights were compared with the V01.00 TIR upper tropospheric CO2 data. The CONTRAIL CO2 "profile" data obtained during the ascending and descending flights over several airports were compared with the TIR CO2 profiles. In the profile comparisons, we applied the TIR averaging kernel functions to the coincident CONTRAIL CO2 profiles. The V01.00 upper atmospheric CO2 data agreed to the CONTRAIL level flight CO2 data on average within 0.5-1%. Some TIR CO2 data showed relatively large differences from the nearest aircraft data, which suggests the existence of several problems such as L1B spectral calibration and nighttime cloud detection issues. The TIR V01.00 CO2 profile data from 9 to 13 km showed better agreement to CONTRAIL CO2 data than the a priori. However, the TIR CO2 data at around and below 5 km had low bias of 1-1.5%. The TIR V01.00 CH4 data generally showed reasonable latitudinal distributions as the previous version. In the Antarctic, unexpected high amounts of CH4 were seen in upper troposphere and lower stratosphere in autumn. This is probably because of the problem of simultaneously retrieved ozone concentration.

Design and qualification of the interferometer for the GOSAT-2 spectrometer

NASA Astrophysics Data System (ADS)

Montembault, Yan; Moreau, Louis; Roux, Michel; Buijs, Henry; Soucy, Marc-André

2016-10-01

GOSAT-2 is the successor of the Greenhouse gases Observing SATellite (GOSAT, "IBUKI") launched in 2009 by Japan Aerospace Exploration Agency (JAXA). GOSAT-2 will continue and enhance space borne measurements of greenhouse gases started by GOSAT and monitor the impacts of climate change and human activities on the carbon cycle. It will also contribute to climate science and climate change related policies. The GOSAT-2 spacecraft will carry two earth observation instruments: FTS-2, the second generation of the TANSO-FTS and CAI-2, a Cloud and Aerosol Imager. Mitsubishi Electric Corporation is the prime contractor of GOSAT-2. Harris is the subcontractor of the spectrometer. ABB, who successfully designed, manufactured, and delivered the interferometer for the TANSO-FTS instrument for GOSAT, is currently delivering the modulator for the FTS-2 instrument to Mitsubishi Electric Corporation. Built on the TANSO-FTS heritage, FTS-2 is a thermal and near infrared sensor for carbon observation based on a Fourier transform spectrometer featuring larger optical throughput than TANSO-FTS. This paper presents an overview of the design of the FTS-2 interferometer as well as key qualification and performance verification activities conducted on the interferometer flight model.

Measurement of Circulating Filarial Antigen Levels in Human Blood with a Point-of-Care Test Strip and a Portable Spectrodensitometer

PubMed Central

Chesnais, Cédric B.; Vlaminck, Johnny; Kunyu-Shako, Billy; Pion, Sébastien D.; Awaca-Uvon, Naomi-Pitchouna; Weil, Gary J.; Mumba, Dieudonné; Boussinesq, Michel

2016-01-01

The Alere Filariasis Test Strip (FTS) is a qualitative, point-of-care diagnostic tool that detects Wuchereria bancrofti circulating filarial antigen (CFA) in human blood, serum, or plasma. The Global Program to Eliminate Lymphatic Filariasis employs the FTS for mapping filariasis-endemic areas and assessing the success of elimination efforts. The objective of this study was to explore the relationship between the intensity of positive test lines obtained by FTS with CFA levels as determined by enzyme-linked immunosorbent assay (ELISA) with blood and plasma samples from 188 individuals who live in a filariasis-endemic area. The intensity of the FTS test line was assessed visually to provide a semiquantitative score (visual Filariasis Test Strip [vFTS]), and line intensity was measured with a portable spectrodensitometer (quantitative Filariasis Test Strip [qFTS]). These results were compared with antigen levels measured by ELISA in plasma from the same subjects. qFTS measurements were highly correlated with vFTS scores (ρ = 0.94; P < 0.001) and with plasma CFA levels (ρ = 0.91; P < 0.001). Thus, qFTS assessment is a convenient method for quantifying W. bancrofti CFA levels in human blood, which are correlated with adult worm burdens. This tool may be useful for assessing the impact of treatment on adult filarial worms in individuals and communities. PMID:27114288

Studying the Immunomodulatory Effects of Small Molecule Ras Inhibitors in Animal Models of Rheumatoid Arthritis

DTIC Science & Technology

2016-10-01

2016 4. TITLE AND SUBTITLE Studying the Immunomodulatory Effects of Small Molecule Ras-Inhibitors in Animal Models of Rheumatoid Arthritis 5a...TERMS Ras GTPases; Rheumatoid Arthritis (RA); Farnesylthiosalicylic acid (FTS); T helper cells, disease-modifying antirheumatic drugs (DMARDs...anergy and to restore IL-2 production. Importantly, T cells from patients with Rheumatoid Arthritis (RA) display augmented activation of the Ras

Studying the Immunomodulatory Effects of Small Molecule Ras-Inhibitors in Animal Models of Rheumatoid Arthritis

DTIC Science & Technology

2016-10-01

Studying the Immunomodulatory Effects of Small Molecule Ras-Inhibitors in Animal Models of Rheumatoid Arthritis 5a. CONTRACT NUMBER 5b. GRANT... Rheumatoid Arthritis (RA); Farnesylthiosalicylic acid (FTS); T helper cells, disease-modifying antirheumatic drugs (DMARDs); targeted synthetic DMARDs 16...active Ras was shown to reverse anergy and to restore IL-2 production. Importantly, T cells from patients with Rheumatoid Arthritis (RA) display

The flight telerobotic servicer and technology transfer

NASA Technical Reports Server (NTRS)

Andary, James F.; Bradford, Kayland Z.

1991-01-01

The Flight Telerobotic Servicer (FTS) project at the Goddard Space Flight Center is developing an advanced telerobotic system to assist in and reduce crew extravehicular activity (EVA) for Space Station Freedom (SSF). The FTS will provide a telerobotic capability in the early phases of the SSF program and will be employed for assembly, maintenance, and inspection applications. The current state of space technology and the general nature of the FTS tasks dictate that the FTS be designed with sophisticated teleoperational capabilities for its internal primary operating mode. However, technologies such as advanced computer vision and autonomous planning techniques would greatly enhance the FTS capabilities to perform autonomously in less structured work environments. Another objective of the FTS program is to accelerate technology transfer from research to U.S. industry.

Technique for the metrology calibration of a Fourier transform spectrometer

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

Spencer, Locke D.; Naylor, David A

2008-11-10

A method is presented for using a Fourier transform spectrometer (FTS) to calibrate the metrology of a second FTS. This technique is particularly useful when the second FTS is inside a cryostat or otherwise inaccessible.

Interactions among the early Escherichia coli divisome proteins revealed by bimolecular fluorescence complementation.

PubMed

Pazos, Manuel; Natale, Paolo; Margolin, William; Vicente, Miguel

2013-12-01

We used bimolecular fluorescence complementation (BiFC) assays to detect protein-protein interactions of all possible pairs of the essential Escherichia coli proto-ring components, FtsZ, FtsA and ZipA, as well as the non-essential FtsZ-associated proteins ZapA and ZapB. We found an unexpected interaction between ZipA and ZapB at potential cell division sites, and when co-overproduced, they induced long narrow constrictions at division sites that were dependent on FtsZ. These assays also uncovered an interaction between ZipA and ZapA that was mediated by FtsZ. BiFC with ZapA and ZapB showed that in addition to their expected interaction at midcell, they also interact at the cell poles. BiFC detected interaction between FtsZ and ZapB at midcell and close to the poles. Results from the remaining pairwise combinations confirmed known interactions between FtsZ and ZipA, and ZapB with itself. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

End of FY2014 Report - Filter Measurement System for Nuclear Material Storage Canisters (Including Altitude Correction for Filter Pressure Drop)

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

Moore, Murray E.; Reeves, Kirk Patrick

2015-02-24

Two LANL FTS (Filter Test System ) devices for nuclear material storage canisters are fully operational. One is located in PF-4 ( i.e. the TA-55 FTS) while the other is located at the Radiation Protection Division’s Aerosol Engineering Facility ( i.e. the TA-3 FTS). The systems are functionally equivalent , with the TA-3 FTS being the test-bed for new additions and for resolving any issues found in the TA-55 FTS. There is currently one unresolved issue regarding the TA-55 FTS device. The canister lid clamp does not give a leak tight seal when testing the 1 QT (quart) or 2more » QT SAVY lids. An adapter plate is being developed that will ensure a correct test configuration when the 1 or 2 QT SAVY lid s are being tested .« less

Multi-color localization microscopy of fixed cells as a promising tool to study organization of bacterial cytoskeleton

NASA Astrophysics Data System (ADS)

Vedyaykin, A. D.; Gorbunov, V. V.; Sabantsev, A. V.; Polinovskaya, V. S.; Vishnyakov, I. E.; Melnikov, A. S.; Serdobintsev, P. Yu; Khodorkovskii, M. A.

2015-11-01

Localization microscopy allows visualization of biological structures with resolution well below the diffraction limit. Localization microscopy was used to study FtsZ organization in Escherichia coli previously in combination with fluorescent protein labeling, but the fact that fluorescent chimeric protein was unable to rescue temperature-sensitive ftsZ mutants suggests that obtained images may not represent native FtsZ structures faithfully. Indirect immunolabeling of FtsZ not only overcomes this problem, but also allows the use of the powerful visualization methods arsenal available for different structures in fixed cells. In this work we simultaneously obtained super-resolution images of FtsZ structures and diffraction-limited or super-resolution images of DNA and cell surface in E. coli, which allows for the study of the spatial arrangement of FtsZ structures with respect to the nucleoid positions and septum formation.

Assessing the Parameterization of Nitric Oxide Emissions By Lightning in a Chemical Transport Model with Nitric Acid Columns from the IASI Satellite Instrument

NASA Astrophysics Data System (ADS)

Cooper, M.; Martin, R.; Wespes, C.; Coheur, P. F.; Clerbaux, C.; Murray, L. T.

2014-12-01

Nitrogen oxides (NOx ≡ NO + NO2) in the free troposphere largely control the production of ozone (O3), an important greenhouse gas and atmospheric oxidant. As HNO3 is the dominant sink of tropospheric NOx, improved understanding of its production and loss mechanisms can help to better constrain NOx emissions, and in turn improve understanding of ozone production and its effect on climate. However, this understanding is inhibited by the scarcity of direct measurements of free tropospheric HNO3, particularly in the tropics. We interpret tropical tropospheric nitric acid columns from the IASI satellite instrument with a global chemical transport model (GEOS-Chem). Overall GEOS-Chem generally agrees with IASI, however we find that the simulation underestimates IASI nitric acid over Southeast Asia by a factor of two. The bias is confirmed by comparing the GEOS-Chem simulation with additional satellite (HIRDLS, ACE-FTS) and aircraft (PEM-Tropics A and PEM-West B) observations of the middle and upper troposphere. We show that this bias can be explained by the parameterization of lightning NOx emissions, primarily from the misrepresentation of concentrated subgrid lightning NOx plumes. We tested a subgrid lightning plume parameterization and found that an additional 0.5 Tg N with an ozone production efficiency of 15 mol/mol would reduce the regional nitric acid bias from 92% to 6% without perturbing the rest of the tropics. Other sensitivity studies such as modified NOx yield per flash, increased altitude of lightning NOx emissions, or changes to convective mass flux or wet deposition of nitric acid required unrealistic changes to reduce the bias. This work demonstrates the importance of a comprehensive lightning parameterization to constraining NOx emissions.

Effects of Lewis acidity of metal oxide promoters on the activity and selectivity of Co-based Fischer–Tropsch synthesis catalysts

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

Johnson, Gregory R.; Bell, Alexis T.

2016-06-17

Metal oxides of Ce, Gd, La, Mn, and Zr were investigated as promoters for improving the activity and selectivity of Co-based FTS catalysts. The extent to which these promoters decrease the selectivity toward CH 4 and increase the selectivity toward C 5+ hydrocarbons was found to depend on both the loading and the composition of the oxide promoter. Elemental mapping by STEM–EDS revealed that the propensity for a given metal oxide to associate with Co affects the sensitivity of the product distribution to changes in promoter loading. For all promoters, a sufficiently high loading resulted in the product distributions becomingmore » insensitive to further increases in promoter loading, very likely due to the formation of a half monolayer of promoter oxide over the Co surface. Simulations suggest that the fraction of Co active sites that are adjacent to the promoter moieties approaches unity at this degree of coverage. The oxidation state of the promoter metal cation under reaction conditions, determined by in situ XANES measurements, was used to calculate relative Lewis acidity of the promoter metal cation. A strong positive correlation was found between the C 5+ product selectivity and the Lewis acidity of the promoter metal cations, suggesting that the promotional effects are a consequence of Lewis acid–base interactions between the reaction intermediates and the promoter metal cations. Rate data obtained at different pressures were used to estimate the apparent rate coefficient and the CO adsorption constant appearing in the Langmuir–Hinshelwood expression that describes the CO consumption kinetics for both unpromoted and the metal oxide-promoted catalysts. Both parameters exhibited positive correlations with the promoter Lewis acidity. In conclusion, these results are consistent with the hypothesis that the metal cations of the promoter act as Lewis acids that interact with the O atom of adsorbed CO to facilitate CO adsorption and dissociation.« less

Revealing the ISM in high redshift starburst galaxies: An analysis of Herschel PACS and SPIRE FTS spectroscopic observations of HerMES and H-ATLAS-selected lensed galaxies

NASA Astrophysics Data System (ADS)

Cooray, Asantha

In the quest to develop a fundamental understanding of galaxy formation and evolution, observations of dusty star-forming galaxies (DSFGs) promise significant progress this decade. The importance of DSFGs is highlighted by the fact that half of the energy emitted by extragalactic sources emerges as dust-reprocessed light at infrared (IR) to sub millimeter wavelength. In the post-herschel\\ era, we are now at a unique position to tackle some of the key questions on galaxy formation and evolution because of the large area Herschel's Key Project surveys (HerMES and H-ATLAS). In particular those surveys have allowed us to identify a sample of 250 strongly gravitationally lensed DSFGs at z > 1. They give us a unique opportunity to dissect the detailed structures and kinematics of DSFGs. The Herschel Science Archive also contains individual follow up data on 44 and 25 of the brightest sources with SPIRE-FTS and PACS, respectively, in the spectroscopy mode, taking over 250 hours in four open-time programs. Only one of the 44 SPIRE FTS targets has yet to appear in the published literature. One of the four include an open-time 2 PACS spectroscopy program that was led at UCI by a former postdoc from the PI's group. That program was initially approved at Priority 2 in 2011, but was triggered in late 2012 and achieved 100% completion during the last two weeks of Herschel lifetime in May 2013. This archival analysis, interpretation, and modeling program involves two parts: (i) PACS spectroscopy in 50 to 200 microns of 25 lensed galaxies in the fine-structure emission lines [SiII]34, [SIII]33, [OIV]26, [OIII]52, [NIII]57 and [OI]63, and the molecular hydrogen H_2 S(0) and S(1). (ii) SPIRE FTS spectroscopy of 44 lensed galaxies, including above 25, over the wavelength range of 200 to 600 microns targeting [CII]158, [OIII]88, [OI]63/145, and [NI]122. The analysis will lead to a better understanding of the ISM of starbursting galaxies that span 1 < z < 3.1 range in redshift and a

75 FR 81628 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... tested for antimicrobial activity against drug resistant bacteria, methicillin- resistant Staphylococcus... antibacterial targeted protein FtsZ. These compounds have a unique mechanism of action which inhibit FtsZ by inhibiting FtsZ GTPase activity. Inhibit drug-susceptible and drug-resistant bacteria. Development Status...

Fast-track surgery after gynaecological oncological surgery: study protocol for a prospective randomised controlled trial.

PubMed

Cui, Ling; Shi, Yu; Zhang, G N

2016-12-15

Fast-track surgery (FTS), also known as enhanced recovery after surgery, is a multidisciplinary approach to accelerate recovery, reduce complications, minimise hospital stay without increasing readmission rates, and reduce health care costs, all without compromising patient safety. The advantages of FTS in abdominal surgery most likely extend to gynaecological surgery, but this is an assumption, as FTS in elective gynaecological surgery has not been well studied. No consensus guidelines have been developed for gynaecological oncological surgery although surgeons have attempted to introduce slightly modified FTS programmes for patients undergoing such surgery. To our knowledge, there are no published randomised controlled trials; however, some studies have shown that FTS in gynaecological oncological surgery leads to early hospital discharge with high levels of patient satisfaction. The aim of this study is whether FTS reduces the length of stay in hospital compared to traditional management. The secondary aim is whether FTS is associated with any increase in post-surgical complications compared to traditional management (for both open and laparoscopic surgery). This trial will prospectively compare FTS and traditional management protocols. The primary endpoint is the length of post-operative hospitalisation (days, mean ± standard deviation), defined as the number of days between the date of discharge and the date of surgery. The secondary endpoints are complications in both groups (FTS versus traditional protocol) occurring during the first 3 months post-operatively including infection (wound infection, lung infection, intraperitoneal infection), post-operative nausea and vomiting, ileus, post-operative haemorrhage, post-operative thrombosis, and the Acute Physiology and Chronic Health Enquiry II score. The advantages of FTS most likely extend to gynaecology, although, to our knowledge, there are no randomised controlled trials. The aim of this study is to

Investigating the governance of autonomous public hospitals in England: multi-site case study of NHS foundation trusts.

PubMed

Allen, Pauline; Keen, Justin; Wright, John; Dempster, Paul; Townsend, Jean; Hutchings, Andrew; Street, Andrew; Verzulli, Rossella

2012-04-01

To investigate the external and internal governance of NHS foundation trusts (FTs), which have increased autonomy, and local members and governors unlike other NHS trusts. In depth, three-year case studies of four FTs; and analysis of national quantitative data on all FT hospitals and NHS Trust hospitals to give national context. Data included 111 interviews with managers, clinicians, governors and members, and local purchasers; observation of meetings; and analysis of FTs' documents. The four case study FTs were similar to other FTs. They had used their increased autonomy to develop more business-like practices. The FT regulator, Monitor, intervened only when there were reported problems in FT performance. National targets applying to the NHS also had a large effect on FT behaviour. FTs saw themselves as part of the local health economy and tried to maintain good relationships with local organisations. Relationships between governors and the FTs' executives were still developing, and not all governors felt able to hold their FT to account. The skills and experience of staff members and governors were under-used in the new governance structures. It is easier to increase autonomy for public hospitals than to increase local accountability. Hospital managers are likely to be interested in making decisions with less central government control, whilst mechanisms for local accountability are notoriously difficult to design and operate. Further consideration of internal governance of FTs is needed. In a deteriorating financial climate, FTs should be better placed to make savings, due to their more business-like practices.

5 CFR Appendix A to 5 Cfr Chapter... - Current Addresses and Geographic Jurisdictions

Code of Federal Regulations, 2010 CFR

2010-01-01

...; telephone: FTS or commercial (312) 353-6306; fax: FTS or commercial (312) 886-5977. (5) Dallas, Texas Regional Office—525 Griffin Street, suite 926, LB-107, Dallas, Texas 75202-1906; telephone: FTS or... Francisco Arizona Denver Arkansas Dallas California San Francisco Colorado Denver Connecticut Boston...

5 CFR Appendix A to 5 Cfr Chapter... - Current Addresses and Geographic Jurisdictions

Code of Federal Regulations, 2011 CFR

2011-01-01

...; telephone: FTS or commercial (312) 353-6306; fax: FTS or commercial (312) 886-5977. (5) Dallas, Texas Regional Office—525 Griffin Street, suite 926, LB-107, Dallas, Texas 75202-1906; telephone: FTS or... Francisco Arizona Denver Arkansas Dallas California San Francisco Colorado Denver Connecticut Boston...

Are NHS foundation trusts able and willing to exercise autonomy? 'You can take a horse to water...'.

PubMed

Exworthy, Mark; Frosini, Francesca; Jones, Lorelei

2011-10-01

Foundation trusts (FTs) have been a central part of the government's National Health Service (NHS) reforms in England since 2004. They illustrate the government's claim to decentralization, by granting greater autonomy to high performing organizations. The number of FTs has grown steadily, reaching 131 in September 2010, over 50% of eligible trusts. Despite this growth, and notwithstanding the fact that organizations which initially became FTs were previously high performing, doubts remain about the implementation of the FT policy. This article examines the implementation of FTs in the NHS and focuses on the nature and exercise of autonomy by FTs. It argues that the ability of FTs to exercise autonomy is in place, but the (relatively limited) extent of implementation may be explained by trusts' lack of willingness to exercise such autonomy. Such unwillingness may be because of continued centralization, unclear policy and financial regimes, fear of negative impacts on relations with other local organizations, and awareness of greater risk to the FT, among others. Addressing the tension between FTs' ability and willingness to exercise autonomy will largely explain the extent to which the government's provider side reforms will be implemented.

The Space Station Freedom Flight Telerobotic Servicer - The design and evolution of a dexterous space robot

NASA Technical Reports Server (NTRS)

Mccain, Harry G.; Andary, James F.; Hewitt, Dennis R.; Haley, Dennis C.

1990-01-01

The Flight Telerobotic Servicer (FTS) will provide a telerobotic capability to the Space Station in the early assembly phases of the program and will be used for assembly, maintenance, and inspection throughout the lifetime of the Station. Here, the FTS design approach to the development of autonomous capabilities is discussed. The FTS telerobotic workstations for the Shuttle and Space Station, and facility for on-orbit storage are examined. The rationale of the FTS with regard to ease of operation, operational versatility, maintainability, safety, and control is discussed.

Characteristics of Four-years of GOSAT/TANSO-FTS TIR V1.0 CO2 and CH4 Products

NASA Astrophysics Data System (ADS)

Saitoh, N.; Kimoto, S.; Sugimura, R.; Imasu, R.; Shiomi, K.; Kuze, A.; Kataoka, F.; Knuteson, R. O.; Machida, T.; Sawa, Y.; Matsuda, H.

2015-12-01

Greenhouse Gases Observing Satellite (GOSAT) was launched on 23 January 2009, and has continued to make global observations, including both nadir and off-nadir measurements, for more than six years since its launch. The thermal infrared (TIR) band of Thermal and Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) on board the GOSAT has observed CO2 and CH4 profiles. We have analyzed the four-year data from 2010 through 2013 of the latest released version of the TIR Level 2 (L2) CO2 and CH4 products (V1.0). Comparisons of the TIR upper atmospheric CO2 product with CO2 data from Comprehensive Observation Network for Trace Gases by Airliner (CONTRAIL) aircraft measurements show that the growth rate estimated from the TIR CO2 data is slightly lower than that from the CONTRAIL data. Overall, the TIR V1.0 CO2 product has better quality in the upper troposphere and lower stratosphere than the a priori judging from comparisons with the collocated aircraft data. In spring and summer, however, the quality of the TIR L2 CO2 products became slightly worse than in the other seasons, especially in the low and northern-mid latitudes. This is because the corresponding a priori had a larger bias and the TIR Level 1B (L1B) radiance spectra might have a larger bias in the spring-summer seasons. Here, we have tested several types of correction methods to modify the L1B spectral bias, and then compared CO2 and CH4 concentrations retrieved after applying spectral bias correction factors with coincident CONTRAIL and HIAPER Pole-to-Pole Observation (HIPPO) aircraft data. The comparison results suggest that the L1B spectral bias correction factor should be changed depending on wavelength. In addition, it should be expressed as a function of on-board internal calibration blackbody temperatures. This is because they are weak season-dependent parameters; they were clearly lower in spring and summer.

Stability of triptorelin in the presence of dermis and epidermis.

PubMed

Bachhav, Yogeshwar G; Kalia, Yogeshvar N

2009-08-13

An important issue with respect to the transdermal delivery of peptides is their stability during transit through the epidermis and dermis before entry into the systemic circulation. The objective of the present study was to evaluate the effect of epidermal and dermal tissue on the stability of the luteinizing hormone releasing hormone superagonist, triptorelin. The decapeptide was dissolved in PBS (pH 7.4) and placed in contact with (i) heat separated epidermis (HSE), (ii) dermatomed skin (0.75 mm; DS) and (iii) full thickness skin (FTS) and the extent of peptide biotransformation monitored as a function of time by HPLC. The results showed that triptorelin was metabolized when in contact with each of the skin tissues. However, there were marked differences with respect to the extent of peptide degradation. Triptorelin was least stable in the presence of FTS. After 3 h exposure to HSE, DS and FTS, the extent of triptorelin degradation was 15.0+/-6.0%, 64.8+/-9.9% and 100%, respectively. After 24 h, further triptorelin degradation had occurred in the samples in contact with HSE and DS--with 51.3+/-6.0% and 87.8+/-4.4%, respectively, of the peptide being degraded. The chromatograms revealed the presence of a degradation peak at a higher retention time than the parent molecule--most probably the free acid.

Ampicillin-Resistant Non-β-Lactamase-Producing Haemophilus influenzae in Spain: Recent Emergence of Clonal Isolates with Increased Resistance to Cefotaxime and Cefixime▿

PubMed Central

García-Cobos, Silvia; Campos, José; Lázaro, Edurne; Román, Federico; Cercenado, Emilia; García-Rey, César; Pérez-Vázquez, María; Oteo, Jesús; de Abajo, Francisco

2007-01-01

The sequence of the ftsI gene encoding the transpeptidase domain of penicillin-binding protein 3 (PBP 3) was determined for 354 nonconsecutive Haemophilus influenzae isolates from Spain; 17.8% of them were ampicillin susceptible, 56% were β-lactamase nonproducing ampicillin resistant (BLNAR), 15.8% were β-lactamase producers and ampicillin resistant, and 10.4% displayed both resistance mechanisms. The ftsI gene sequences had 28 different mutation patterns and amino acid substitutions at 23 positions. Some 93.2% of the BLNAR strains had amino acid substitutions at the Lys-Thr-Gly (KTG) motif, the two most common being Asn526 to Lys (83.9%) and Arg517 to His (9.3%). Amino acid substitutions at positions 377, 385, and 389, which conferred cefotaxime and cefixime MICs 10 to 60 times higher than those of susceptible strains, were found for the first time in Europe. In 72 isolates for which the repressor acrR gene of the AcrAB efflux pump was sequenced, numerous amino acid substitutions were found. Eight isolates with ampicillin MICs of 0.25 to 2 μg/ml showed changes that predicted the early termination of the acrR reading frame. Pulsed-field gel electrophoresis analysis demonstrated that most BLNAR strains were genetically diverse, although clonal dissemination was detected in a group of isolates presenting with increased resistance to cefotaxime and cefixime. Background antibiotic use at the community level revealed a marked trend toward increased amoxicillin-clavulanic acid consumption. BLNAR H. influenzae strains have arisen by vertical and horizontal spread and have evolved to adapt rapidly to the increased selective pressures posed by the use of oral penicillins and cephalosporins. PMID:17470649

Frequency, characteristics, and perceived functions of emotional future thinking in daily life.

PubMed

Barsics, Catherine; Van der Linden, Martial; D'Argembeau, Arnaud

2016-01-01

While many thoughts and mental images that people form about their personal future refer to emotionally significant events, there is still little empirical data on the frequency and nature of emotional future-oriented thoughts (EmoFTs) that occur in natural settings. In the present study, participants recorded EmoFTs occurring in daily life and rated their characteristics, emotional properties, and perceived functions. The results showed that EmoFTs are frequent, occur in various contexts, and are perceived to fulfil important functions, mostly related to goal pursuit and emotion regulation. When distinguishing between anticipatory and anticipated emotions (i.e., emotions experienced in the present versus emotions expected to occur in the future), a positivity bias in the frequency of EmoFTs was found to be restricted to anticipated emotions. The representational format and perceived function of EmoFTs varied according to their affective valence, and the intensity of anticipatory and anticipated emotions were influenced by the personal importance and amount of visual imagery of EmoFTs. Mood states preceding EmoFTs influenced their emotional components, which, in turn, impacted ensuing mood states. Overall, these findings shed further light on the emotional properties of future-oriented thoughts that are experienced in daily life.

Fourier spectroscopy in planetary research

NASA Technical Reports Server (NTRS)

Hanel, R. A.; Kunde, V. G.

1975-01-01

The application of Fourier Transform Spectroscopy (FTS) to planetary research is reviewed. The survey includes FTS observations of the sun, all the planets except Uranus and Pluto, The Galilean satellites and Saturn's rings. Instrumentation and scientific results are considered. The prospects and limitations of FTS for planetary research in the forthcoming years are discussed.

Fourier spectroscopy and planetary research

NASA Technical Reports Server (NTRS)

Hanel, R. A.; Kunde, V. G.

1974-01-01

The application of Fourier Transform Spectroscopy (FTS) to planetary research is reviewed. The survey includes FTS observations of the sun, all the planets except Uranus and Pluto, the Galilean satellites and Saturn's rings. Instrumentation and scientific results are considered and the prospects and limitations of FTS for planetary research in the forthcoming years are discussed.

Warm and cold molecular gas conditions modeled in 87 galaxies observed by the Herschel SPIRE FTS

NASA Astrophysics Data System (ADS)

Kamenetzky, Julia; Rangwala, Naseem; Glenn, Jason

2018-01-01

Molecular gas is the raw material for star formation, and like the interstellar medium (ISM) in general, it can exist in regions of higher and lower excitation. Rotational transitions of the CO molecule are bright and sensitive to cold molecular gas. While the majority of the molecular gas exists in the very cold component traced by CO J=1-0, the higher-J lines trace the highly excited gas that may be more indicative of star formation processes. The atmosphere is opaque to these lines, but the launch of the Herschel Space Observatory made them accessible for study of Galactic and extragalactic sources. We have conducted two-component, non-local thermodynamic equilibrium (non-LTE) modeling of the CO lines from J=1‑0 through J=13‑12 in 87 galaxies observed by the Herschel SPIRE Fourier Transform Spectrometer (FTS). We used the nested sampling algorithm Multinest to compare the measured CO spectral line energy distributions (SLEDs) to the ones produced by a custom version of the non-LTE code RADEX. This allowed us to fully examine the degeneracies in parameter space for kinetic temperature, molecular gas density, CO column density, and area filling factor.Here we discuss the major findings of our study, as well as the important implications of two-component molecular gas modeling. The average pressure of the warm gas is slightly correlated with galaxy LFIR, but that of the cold gas is not. A high-J (such as J=11-10) to J=1-0 line ratio is diagnostic of warm component pressure. We find a very large spread in our derived values of "alpha-CO," with no discernable trend with LFIR, and average molecular gas depletion times that decrease with LFIR. If only a few molecular lines are available in a galaxy's SLED, the limited ability to model only one component will change the results. A one-component fit often underestimates the flux of carbon monoxide (CO) J=1‑0 and the mass. If low-J lines are not included, mass is underestimated by an order of magnitude. Even when

Hydrogen Cyanide in the Upper Troposphere: GEM-AQ Simulation and Comparison with ACE-FTS Observations

NASA Technical Reports Server (NTRS)

Lupu, A.; Kaminski, J. W.; Neary, L.; McConnell, J. C.; Toyota, K.; Rinsland, C. P.; Bernath, P. F.; Walker, K. A.; Boone, C. D.; Nagahama, Y.;

Characterization and Evolution of Cell Division and Cell Wall Synthesis Genes in the Bacterial Phyla Verrucomicrobia, Lentisphaerae, Chlamydiae, and Planctomycetes and Phylogenetic Comparison with rRNA Genes▿ †

PubMed Central

Pilhofer, Martin; Rappl, Kristina; Eckl, Christina; Bauer, Andreas Peter; Ludwig, Wolfgang; Schleifer, Karl-Heinz; Petroni, Giulio

2008-01-01

In the past, studies on the relationships of the bacterial phyla Planctomycetes, Chlamydiae, Lentisphaerae, and Verrucomicrobia using different phylogenetic markers have been controversial. Investigations based on 16S rRNA sequence analyses suggested a relationship of the four phyla, showing the branching order Planctomycetes, Chlamydiae, Verrucomicrobia/Lentisphaerae. Phylogenetic analyses of 23S rRNA genes in this study also support a monophyletic grouping and their branching order—this grouping is significant for understanding cell division, since the major bacterial cell division protein FtsZ is absent from members of two of the phyla Chlamydiae and Planctomycetes. In Verrucomicrobia, knowledge about cell division is mainly restricted to the recent report of ftsZ in the closely related genera Prosthecobacter and Verrucomicrobium. In this study, genes of the conserved division and cell wall (dcw) cluster (ddl, ftsQ, ftsA, and ftsZ) were characterized in all verrucomicrobial subdivisions (1 to 4) with cultivable representatives (1 to 4). Sequence analyses and transcriptional analyses in Verrucomicrobia and genome data analyses in Lentisphaerae suggested that cell division is based on FtsZ in all verrucomicrobial subdivisions and possibly also in the sister phylum Lentisphaerae. Comprehensive sequence analyses of available genome data for representatives of Verrucomicrobia, Lentisphaerae, Chlamydiae, and Planctomycetes strongly indicate that their last common ancestor possessed a conserved, ancestral type of dcw gene cluster and an FtsZ-based cell division mechanism. This implies that Planctomycetes and Chlamydiae may have shifted independently to a non-FtsZ-based cell division mechanism after their separate branchings from their last common ancestor with Verrucomicrobia. PMID:18310338

Flight Telerobotic Servicer prototype simulator

NASA Astrophysics Data System (ADS)

Schein, Rob; Krauze, Linda; Hartley, Craig; Dickenson, Alan; Lavecchia, Tom; Working, Bob

A prototype simulator for the Flight Telerobotic Servicer (FTS) system is described for use in the design development of the FTS, emphasizing the hand controller and user interface. The simulator utilizes a graphics workstation based on rapid prototyping tools for systems analyses of the use of the user interface and the hand controller. Kinematic modeling, manipulator-control algorithms, and communications programs are contained in the software for the simulator. The hardwired FTS panels and operator interface for use on the STS Orbiter are represented graphically, and the simulated controls function as the final FTS system configuration does. The robotic arm moves based on the user hand-controller interface, and the joint angles and other data are given on the prototype of the user interface. This graphics simulation tool provides the means for familiarizing crewmembers with the FTS system operation, displays, and controls.

Food traceability systems in China: The current status of and future perspectives on food supply chain databases, legal support, and technological research and support for food safety regulation.

PubMed

Tang, Qi; Li, Jiajia; Sun, Mei; Lv, Jun; Gai, Ruoyan; Mei, Lin; Xu, Lingzhong

2015-02-01

Over the past few decades, the field of food security has witnessed numerous problems and incidents that have garnered public attention. Given this serious situation, the food traceability system (FTS) has become part of the expanding food safety continuum to reduce the risk of food safety problems. This article reviews a great deal of the related literature and results from previous studies of FTS to corroborate this contention. This article describes the development and benefits of FTS in developed countries like the United States of America (USA), Japan, and some European countries. Problems with existing FTS in China are noted, including a lack of a complete database, inadequate laws and regulations, and lagging technological research into FTS. This article puts forward several suggestions for the future, including improvement of information websites, clarification of regulatory responsibilities, and promotion of technological research.

Divisome-dependent subcellular localization of cell-cell joining protein SepJ in the filamentous cyanobacterium Anabaena.

PubMed

Ramos-León, Félix; Mariscal, Vicente; Frías, José E; Flores, Enrique; Herrero, Antonia

2015-05-01

Heterocyst-forming cyanobacteria are multicellular organisms that grow as filaments that can be hundreds of cells long. Septal junction complexes, of which SepJ is a possible component, appear to join the cells in the filament. SepJ is a cytoplasmic membrane protein that contains a long predicted periplasmic section and localizes not only to the cell poles in the intercellular septa but also to a position similar to a Z ring when cell division starts suggesting a relation with the divisome. Here, we created a mutant of Anabaena sp. strain PCC 7120 in which the essential divisome gene ftsZ is expressed from a synthetic NtcA-dependent promoter, whose activity depends on the nitrogen source. In the presence of ammonium, low levels of FtsZ were produced, and the subcellular localization of SepJ, which was investigated by immunofluorescence, was impaired. Possible interactions of SepJ with itself and with divisome proteins FtsZ, FtsQ and FtsW were investigated using the bacterial two-hybrid system. We found SepJ self-interaction and a specific interaction with FtsQ, confirmed by co-purification and involving parts of the SepJ and FtsQ periplasmic sections. Therefore, SepJ can form multimers, and in Anabaena, the divisome has a role beyond cell division, localizing a septal protein essential for multicellularity. © 2015 John Wiley & Sons Ltd.

VizieR Online Data Catalog: NiI transition probability measurements (Wood+, 2014)

NASA Astrophysics Data System (ADS)

Wood, M. P.; Lawler, J. E.; Sneden, C.; Cowan, J. J.

2014-04-01

As in much of our previous branching fraction work, this NiI branching fraction study makes use of archived FTS data from both the 1.0m Fourier Transform Spectrometer (FTS) previously at the National Solar Observatory (NSO) on Kitt Peak and the Chelsea Instruments FT500 UV FTS at Lund University in Sweden. Table 1 lists the 37 FTS spectra used in our NiI branching fraction study. All NSO spectra, raw interferograms, and header files are available in the NSO electronic archives. The 80 CCD frames of spectra from commercial Ni HCD lamps of the echelle spectrograph are listed in Table 2. (6 data files).

Bias assessment of lower and middle tropospheric CO2 concentrations of GOSAT/TANSO-FTS TIR version 1 product

NASA Astrophysics Data System (ADS)

Saitoh, Naoko; Kimoto, Shuhei; Sugimura, Ryo; Imasu, Ryoichi; Shiomi, Kei; Kuze, Akihiko; Niwa, Yosuke; Machida, Toshinobu; Sawa, Yousuke; Matsueda, Hidekazu

2017-10-01

CO2 observations in the free troposphere can be useful for constraining CO2 source and sink estimates at the surface since they represent CO2 concentrations away from point source emissions. The thermal infrared (TIR) band of the Thermal and Near Infrared Sensor for Carbon Observation (TANSO) Fourier transform spectrometer (FTS) on board the Greenhouse Gases Observing Satellite (GOSAT) has been observing global CO2 concentrations in the free troposphere for about 8 years and thus could provide a dataset with which to evaluate the vertical transport of CO2 from the surface to the upper atmosphere. This study evaluated biases in the TIR version 1 (V1) CO2 product in the lower troposphere (LT) and the middle troposphere (MT) (736-287 hPa), on the basis of comparisons with CO2 profiles obtained over airports using Continuous CO2 Measuring Equipment (CME) in the Comprehensive Observation Network for Trace gases by AIrLiner (CONTRAIL) project. Bias-correction values are presented for TIR CO2 data for each pressure layer in the LT and MT regions during each season and in each latitude band: 40-20° S, 20° S-20° N, 20-40° N, and 40-60° N. TIR V1 CO2 data had consistent negative biases of 1-1.5 % compared with CME CO2 data in the LT and MT regions, with the largest negative biases at 541-398 hPa, partly due to the use of 10 µm CO2 absorption band in conjunction with 15 and 9 µm absorption bands in the V1 retrieval algorithm. Global comparisons between TIR CO2 data to which the bias-correction values were applied and CO2 data simulated by a transport model based on the Nonhydrostatic ICosahedral Atmospheric Model (NICAM-TM) confirmed the validity of the bias-correction values evaluated over airports in limited areas. In low latitudes in the upper MT region (398-287 hPa), however, TIR CO2 data in northern summer were overcorrected by these bias-correction values; this is because the bias-correction values were determined using comparisons mainly over airports in

Air Force Flight Screening: Evolutionary Changes, 1917-2003

DTIC Science & Technology

2004-12-01

US), FFA (Switzerland), Siai Marchetti (Italy), SAAB (Sweden), Slingsby (United Kingdom), Glassair (US), Piper (US), American General (US), and...Jumper, USAF/CC, [Academy Flight Screening program], 10 Apr 03, 3) BBP , 557 FTS/CC, “USAF 66 As the...Academy Flight Screening (AFS) Program,” 4 Feb 03, 4) BBP , 557 FTS/CC, “AFS Funding,” 22 Jan 03, 5) Position Paper, 557 FTS/CC

Ribosome binding induces repositioning of the signal recognition particle receptor on the translocon

PubMed Central

Kuhn, Patrick; Draycheva, Albena; Vogt, Andreas; Petriman, Narcis-Adrian; Sturm, Lukas; Drepper, Friedel; Warscheid, Bettina; Wintermeyer, Wolfgang

2015-01-01

Cotranslational protein targeting delivers proteins to the bacterial cytoplasmic membrane or to the eukaryotic endoplasmic reticulum membrane. The signal recognition particle (SRP) binds to signal sequences emerging from the ribosomal tunnel and targets the ribosome-nascent-chain complex (RNC) to the SRP receptor, termed FtsY in bacteria. FtsY interacts with the fifth cytosolic loop of SecY in the SecYEG translocon, but the functional role of the interaction is unclear. By using photo-cross-linking and fluorescence resonance energy transfer measurements, we show that FtsY–SecY complex formation is guanosine triphosphate independent but requires a phospholipid environment. Binding of an SRP–RNC complex exposing a hydrophobic transmembrane segment induces a rearrangement of the SecY–FtsY complex, which allows the subsequent contact between SecY and ribosomal protein uL23. These results suggest that direct RNC transfer to the translocon is guided by the interaction between SRP and translocon-bound FtsY in a quaternary targeting complex. PMID:26459600

Feeding the gut after revisional bariatric surgery: The fate of 126 enteral access tubes.

PubMed

Strong, Andrew T; Fayazzadeh, Hana; Sharma, Gautam; El-Hayek, Kevin; Kroh, Matthew; Rodriguez, John

2018-03-09

Revisional bariatric surgery (RBS) is associated with higher complication rates compared with primary bariatric surgery. Feeding tubes (FTs), including gastrostomy and jejunostomy tubes placed during RBS, may serve as a safety net to provide nutrition when oral intake is contraindicated or limited; however, FTs in this setting have not been well investigated. This study aims to determine complications, use, and duration of FTs placed during RBS. A high-volume academic medical center in the United States. Included patients underwent RBS between January 2008 and December 2016 with FTs placed at the time of RBS. There were 126 patients identified (84.9% female, 76.2% Caucasian, mean age 53.4-±10.9 yr). Patients had previously undergone Roux-en-Y gastric bypass (34.1%), vertical banded gastroplasty (27.8%), and adjustable gastric band (14.3%). Indications for RBS included correction of complication of prior bariatric surgeries (50%), weight regain/failure to lose weight (32.3%), or both (17.3%). Most FTs were placed in the excluded stomach (89.7%), and median tube size was 18 F. FTs were used for feeding in 68.2% of patients, with feeding initiated in a median of 2 days. Leakage around the tube (32.5%) and pain (26.8%) were common complaints. Significant tube-related complications included infection (9.1%), dislodgement (5.9%), reintervention (5.8%), and reoperation (2.8%); 16.7% experienced at least 1 significant complication. FTs were removed at a median of 36 days. FTs may aid in prevention of perioperative dehydration and malnutrition after RBS, but should not be considered a benign intervention. FT use should be balanced against institutional outcomes and care goals. Copyright © 2018 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

A multi-center field study of two point-of-care tests for circulating Wuchereria bancrofti antigenemia in Africa

PubMed Central

Chesnais, Cédric B.; Awaca-Uvon, Naomi-Pitchouna; Bolay, Fatoma K.; Boussinesq, Michel; Fischer, Peter U.; Gankpala, Lincoln; Meite, Aboulaye; Missamou, François; Pion, Sébastien D.

2017-01-01

Background The Global Programme to Eliminate Lymphatic Filariasis uses point-of-care tests for circulating filarial antigenemia (CFA) to map endemic areas and for monitoring and evaluating the success of mass drug administration (MDA) programs. We compared the performance of the reference BinaxNOW Filariasis card test (ICT, introduced in 1997) with the Alere Filariasis Test Strip (FTS, introduced in 2013) in 5 endemic study sites in Africa. Methodology The tests were compared prior to MDA in two study sites (Congo and Côte d'Ivoire) and in three sites that had received MDA (DRC and 2 sites in Liberia). Data were analyzed with regard to % positivity, % agreement, and heterogeneity. Models evaluated potential effects of age, gender, and blood microfilaria (Mf) counts in individuals and effects of endemicity and history of MDA at the village level as potential factors linked to higher sensitivity of the FTS. Lastly, we assessed relationships between CFA scores and Mf in pre- and post-MDA settings. Principal findings Paired test results were available for 3,682 individuals. Antigenemia rates were 8% and 22% higher by FTS than by ICT in pre-MDA and in post-MDA sites, respectively. FTS/ICT ratios were higher in areas with low infection rates. The probability of having microfilaremia was much higher in persons with CFA scores >1 in untreated areas. However, this was not true in post-MDA settings. Conclusions/Significance This study has provided extensive new information on the performance of the FTS compared to ICT in Africa and it has confirmed the increased sensitivity of FTS reported in prior studies. Variability in FTS/ICT was related in part to endemicity level, history of MDA, and perhaps to the medications used for MDA. These results suggest that FTS should be superior to ICT for mapping, for transmission assessment surveys, and for post-MDA surveillance. PMID:28892473

A multi-center field study of two point-of-care tests for circulating Wuchereria bancrofti antigenemia in Africa.

PubMed

Chesnais, Cédric B; Awaca-Uvon, Naomi-Pitchouna; Bolay, Fatoma K; Boussinesq, Michel; Fischer, Peter U; Gankpala, Lincoln; Meite, Aboulaye; Missamou, François; Pion, Sébastien D; Weil, Gary J

2017-09-01

The Global Programme to Eliminate Lymphatic Filariasis uses point-of-care tests for circulating filarial antigenemia (CFA) to map endemic areas and for monitoring and evaluating the success of mass drug administration (MDA) programs. We compared the performance of the reference BinaxNOW Filariasis card test (ICT, introduced in 1997) with the Alere Filariasis Test Strip (FTS, introduced in 2013) in 5 endemic study sites in Africa. The tests were compared prior to MDA in two study sites (Congo and Côte d'Ivoire) and in three sites that had received MDA (DRC and 2 sites in Liberia). Data were analyzed with regard to % positivity, % agreement, and heterogeneity. Models evaluated potential effects of age, gender, and blood microfilaria (Mf) counts in individuals and effects of endemicity and history of MDA at the village level as potential factors linked to higher sensitivity of the FTS. Lastly, we assessed relationships between CFA scores and Mf in pre- and post-MDA settings. Paired test results were available for 3,682 individuals. Antigenemia rates were 8% and 22% higher by FTS than by ICT in pre-MDA and in post-MDA sites, respectively. FTS/ICT ratios were higher in areas with low infection rates. The probability of having microfilaremia was much higher in persons with CFA scores >1 in untreated areas. However, this was not true in post-MDA settings. This study has provided extensive new information on the performance of the FTS compared to ICT in Africa and it has confirmed the increased sensitivity of FTS reported in prior studies. Variability in FTS/ICT was related in part to endemicity level, history of MDA, and perhaps to the medications used for MDA. These results suggest that FTS should be superior to ICT for mapping, for transmission assessment surveys, and for post-MDA surveillance.

Adaptation of model proteins from cold to hot environments involves continuous and small adjustments of average parameters related to amino acid composition.

PubMed

De Vendittis, Emmanuele; Castellano, Immacolata; Cotugno, Roberta; Ruocco, Maria Rosaria; Raimo, Gennaro; Masullo, Mariorosario

2008-01-07

The growth temperature adaptation of six model proteins has been studied in 42 microorganisms belonging to eubacterial and archaeal kingdoms, covering optimum growth temperatures from 7 to 103 degrees C. The selected proteins include three elongation factors involved in translation, the enzymes glyceraldehyde-3-phosphate dehydrogenase and superoxide dismutase, the cell division protein FtsZ. The common strategy of protein adaptation from cold to hot environments implies the occurrence of small changes in the amino acid composition, without altering the overall structure of the macromolecule. These continuous adjustments were investigated through parameters related to the amino acid composition of each protein. The average value per residue of mass, volume and accessible surface area allowed an evaluation of the usage of bulky residues, whereas the average hydrophobicity reflected that of hydrophobic residues. The specific proportion of bulky and hydrophobic residues in each protein almost linearly increased with the temperature of the host microorganism. This finding agrees with the structural and functional properties exhibited by proteins in differently adapted sources, thus explaining the great compactness or the high flexibility exhibited by (hyper)thermophilic or psychrophilic proteins, respectively. Indeed, heat-adapted proteins incline toward the usage of heavier-size and more hydrophobic residues with respect to mesophiles, whereas the cold-adapted macromolecules show the opposite behavior with a certain preference for smaller-size and less hydrophobic residues. An investigation on the different increase of bulky residues along with the growth temperature observed in the six model proteins suggests the relevance of the possible different role and/or structure organization played by protein domains. The significance of the linear correlations between growth temperature and parameters related to the amino acid composition improved when the analysis was

The flight telerobotic servicer Tinman concept: System design drivers and task analysis

NASA Technical Reports Server (NTRS)

Andary, J. F.; Hewitt, D. R.; Hinkal, S. W.

1989-01-01

A study was conducted to develop a preliminary definition of the Flight Telerobotic Servicer (FTS) that could be used to understand the operational concepts and scenarios for the FTS. Called the Tinman, this design concept was also used to begin the process of establishing resources and interfaces for the FTS on Space Station Freedom, the National Space Transportation System shuttle orbiter, and the Orbital Maneuvering vehicle. Starting with an analysis of the requirements and task capabilities as stated in the Phase B study requirements document, the study identified eight major design drivers for the FTS. Each of these design drivers and their impacts on the Tinman design concept are described. Next, the planning that is currently underway for providing resources for the FTS on Space Station Freedom is discussed, including up to 2000 W of peak power, up to four color video channels, and command and data rates up to 500 kbps between the telerobot and the control station. Finally, an example is presented to show how the Tinman design concept was used to analyze task scenarios and explore the operational capabilities of the FTS. A structured methodology using a standard terminology consistent with the NASA/National Bureau of Standards Standard Reference Model for Telerobot Control System Architecture (NASREM) was developed for this analysis.

Controlling cell volume for efficient PHB production by Halomonas.

PubMed

Jiang, Xiao-Ran; Yao, Zhi-Hao; Chen, Guo-Qiang

2017-11-01

Bacterial morphology is decided by cytoskeleton protein MreB and cell division protein FtsZ encoded by essential genes mreB and ftsZ, respectively. Inactivating mreB and ftsZ lead to increasing cell sizes and cell lengths, respectively, yet seriously reduce cell growth ability. Here we develop a temperature-responsible plasmid expression system for compensated expression of relevant gene(s) in mreB or ftsZ disrupted recombinants H. campaniensis LS21, allowing mreB or ftsZ disrupted recombinants to grow normally at 30°C in a bioreactor for 12h so that a certain cell density can be reached, followed by 36h cell size expansions or cell shape elongations at elevated 37°C at which the mreB and ftsZ encoded plasmid pTKmf failed to replicate in the recombinants and thus lost themselves. Finally, 80% PHB yield increase was achieved via controllable morphology manipulated H. campaniensis LS21. It is concluded that controllable expanding cell volumes (widths or lengths) provides more spaces for accumulating more inclusion body polyhydroxybutyrate (PHB) and the resulting cell gravity precipitation benefits the final separation of cells and product during downstream. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Skin corrosion test: a comparison between reconstructed human epidermis and full thickness skin models.

PubMed

Catarino, Carolina Motter; do Nascimento Pedrosa, Tatiana; Pennacchi, Paula Comune; de Assis, Silvia Romano; Gimenes, Fabrícia; Consolaro, Márcia Edilaine Lopes; de Moraes Barros, Silvia Berlanga; Maria-Engler, Silvya Stuchi

2018-04-01

Currently, there is a strong global trend towards the development of in vitro models to replace the use of animals in safety evaluation tests. Reconstructed Human Epidermis (RHE) models have been employed as an alternative method to animal testing of skin corrosion and irritation potential of chemical compounds. However, the consequences of an absence of the dermal compartment in these models should be considered since the cross-talk between fibroblasts and keratinocytes is fundamental for promoting proper epidermal stratification, homeostasis, inflammatory response and wound healing. In this study, we compare in-house developed models of Reconstructed Human Epidermis (i.e. USP-RHE) and full thickness skin (i.e. USP-FTS) regarding their response when submitted to skin corrosion assays, based on Guideline 431 (OECD). The results show that both models correctly classified the four substances tested (2-phenylethyl bromide, benzylacetone, lactic acid, octanoic acid) as corrosive or non-corrosive. Furthermore, we have demonstrated higher cell viability of the USP-FTS model compared to the USP-RHE model, a sign of its improved barrier function, following the exposure to the substances test on the corrosion assay. This emphasizes the importance of employing in vitro models that are more physiologically relevant and that better mimic the in vivo situation for the toxicological screening of substances. Copyright © 2018 Elsevier B.V. All rights reserved.

ACE-FTS observations of pyrogenic trace species in boreal biomass burning plumes during BORTAS

NASA Astrophysics Data System (ADS)

Tereszchuk, K. A.; González Abad, G.; Clerbaux, C.; Hadji-Lazaro, J.; Hurtmans, D.; Coheur, P.-F.; Bernath, P. F.

2013-05-01

To further our understanding of the effects of biomass burning emissions on atmospheric composition, the BORTAS campaign (BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites) was conducted on 12 July to 3 August 2011 during the boreal forest fire season in Canada. The simultaneous aerial, ground and satellite measurement campaign sought to record instances of boreal biomass burning to measure the tropospheric volume mixing ratios (VMRs) of short- and long-lived trace molecular species from biomass burning emissions. The goal was to investigate the connection between the composition and the distribution of these pyrogenic outflows and their resulting perturbation to atmospheric chemistry, with particular focus on oxidant species to determine the overall impact on the oxidizing capacity of the free troposphere. Measurements of pyrogenic trace species in boreal biomass burning plumes were made by the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) onboard the Canadian Space Agency (CSA) SCISAT-1 satellite during the BORTAS campaign. Even though biomass burning emissions are typically confined to the boundary layer, outflows are often injected into the upper troposphere by isolated convection and fire-related convective processes, thus allowing space-borne instruments to measure these pyrogenic outflows. An extensive set of 14 molecules - CH3OH, C2H2, C2H6, C3H6O, CO, HCN, HCOOH, HNO3, H2CO, NO, NO2, OCS, O3, and PAN - have been analysed. Included in this analysis is the calculation of age-dependent sets of enhancement ratios for each of the species originating from fires in North America (Canada, Alaska) and Siberia for a period of up to 7 days. Ratio values for the shorter lived primary pyrogenic species decrease over time primarily due to oxidation by the OH radical as the plume ages and values for longer lived species such as HCN and C2H6 remain relatively unchanged. Increasing negative values are

Fourier Transform Spectrometer System

NASA Technical Reports Server (NTRS)

Campbell, Joel F. (Inventor)

2014-01-01

A Fourier transform spectrometer (FTS) data acquisition system includes an FTS spectrometer that receives a spectral signal and a laser signal. The system further includes a wideband detector, which is in communication with the FTS spectrometer and receives the spectral signal and laser signal from the FTS spectrometer. The wideband detector produces a composite signal comprising the laser signal and the spectral signal. The system further comprises a converter in communication with the wideband detector to receive and digitize the composite signal. The system further includes a signal processing unit that receives the composite signal from the converter. The signal processing unit further filters the laser signal and the spectral signal from the composite signal and demodulates the laser signal, to produce velocity corrected spectral data.

Filter Measurement System for Nuclear Material Storage Canisters. End of Year Report FY 2013

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

Moore, Murray E.; Reeves, Kirk P.

2014-02-03

A test system has been developed at Los Alamos National Laboratory to measure the aerosol collection efficiency of filters in the lids of storage canisters for special nuclear materials. Two FTS (filter test system) devices have been constructed; one will be used in the LANL TA-55 facility with lids from canisters that have stored nuclear material. The other FTS device will be used in TA-3 at the Radiation Protection Division’s Aerosol Engineering Facility. The TA-3 system will have an expanded analytical capability, compared to the TA-55 system that will be used for operational performance testing. The LANL FTS is intendedmore » to be automatic in operation, with independent instrument checks for each system component. The FTS has been described in a complete P&ID (piping and instrumentation diagram) sketch, included in this report. The TA-3 FTS system is currently in a proof-of-concept status, and TA-55 FTS is a production-quality prototype. The LANL specification for (Hagan and SAVY) storage canisters requires the filter shall “capture greater than 99.97% of 0.45-micron mean diameter dioctyl phthalate (DOP) aerosol at the rated flow with a DOP concentration of 65±15 micrograms per liter”. The percent penetration (PEN%) and pressure drop (DP) of fifteen (15) Hagan canister lids were measured by NFT Inc. (Golden, CO) over a period of time, starting in the year 2002. The Los Alamos FTS measured these quantities on June 21, 2013 and on Oct. 30, 2013. The LANL(6-21-2013) results did not statistically match the NFT Inc. data, and the LANL FTS system was re-evaluated, and the aerosol generator was replaced and the air flow measurement method was corrected. The subsequent LANL(10-30-2013) tests indicate that the PEN% results are statistically identical to the NFT Inc. results. The LANL(10-30-2013) pressure drop measurements are closer to the NFT Inc. data, but future work will be investigated. An operating procedure for the FTS (filter test system) was written

Cense Explosion Test Program. Report 1. Cense 1. Explosions in Sandstone

DTIC Science & Technology

1977-09-01

series, "Analysis and Summary of CENSE Data." 10 * _ CHAPTER 2 APPROACH 2.1 DESCRIPTION OF TEST SITE An exposed outcrop of Kayenta sandstone with 180...ft/s seismic velocity previously determined (References 12-14) for the unweathered upper zone of the Kayenta sandstone. 16 I The P-wave propagation...Propagation along the horizontal radial was 8400 ft/s. The seismic velocity pre- viously determined for Kayenta sandstone in this area was 7500 ft/s

Application of the Aqueous Porous Pathway Model to Quantify the Effect of Sodium Lauryl Sulfate on Ultrasound-Induced Skin Structural Perturbation

PubMed Central

Polat, Baris E.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert

2011-01-01

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (ε/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ε/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, while LFS-treated FTS and STS have lower ε/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. PMID:20963845

Application of the aqueous porous pathway model to quantify the effect of sodium lauryl sulfate on ultrasound-induced skin structural perturbation.

PubMed

Polat, Baris E; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert

2011-04-01

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (ε/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ε/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, whereas LFS-treated FTS and STS have lower ε/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. Copyright © 2010 Wiley-Liss, Inc.

Force generation in bacteria without nucleotide-dependent bending of cytoskeletal filaments.

PubMed

Ghosh, Biplab; Sain, Anirban

2011-05-01

Binary cell division in bacteria occurs via the formation and subsequent contraction of a polymeric ring, the so-called Z ring, at the middle of the cell. This ring is made of filamenting temperature-sensitive Z (FtsZ) proteins and it shrinks in radius to generate a contractile radial force on the cell membrane. Although a few models have been proposed, the ring contraction mechanism still remains a mystery. The models rely on various physical properties of the FtsZ filaments, some of which have been verified through in vitro experiments and some of which remain unclear. A feature common to all these models is the hydrolysis-driven transition of FtsZ filaments from straight to curved conformations. While the intrinsic curvature of FtsZ filaments has been experimentally established beyond doubt, evidence has been mounting against the existence of any transition between the straight FtsZ-GTP and the curved FtsZ-GDP conformations. Preliminary results from our earlier work [B. Ghosh and A. Sain, Phys. Rev. Lett. 101, 178101 (2008)] indicated that hydrolysis-induced bending is not necessary for Z-ring contraction. Since then many new experimental observations have been reported on this subject and in view of these here we argue that our model appears even more plausible than before. In addition, we have explored more realistic features, such as how the length distribution of FtsZ filaments in the cytoplasm may influence the contraction dynamics, and we have also demonstrated that the Z ring retains approximately the same number of monomers, although not the same monomers, during the course of contraction as reported by fluorescence experiments.

Observations of tropospheric trace gases from GOSAT thermal infrared spectra

NASA Astrophysics Data System (ADS)

Ohyama, Hirofumi; Shiomi, Kei; Kawakami, Shuji; Nakajima, Masakatsu; Maki, Takashi; Deushi, Makoto

2013-04-01

Thermal And Near infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS), which is one of the sensors onboard the Greenhouse gases Observing SATellite (GOSAT), measures the sunlight backscattered by the Earth's surface and atmosphere as well as the thermal radiance emitted from the Earth. Atmospheric trace gases such as ozone (O3), water vapor (H2O and HDO), methanol (CH3OH) and ammonia (NH3) are derived from the thermal infrared spectral radiance recorded with the TANSO-FTS by an optimal estimation retrieval approach. TANSO-FTS total ozone columns are compared with Dobson spectrophotometer and Ozone Monitoring Instrument (OMI) data. The TANSO-FTS total ozone retrievals exhibit a positive bias of 3-4% with a root-mean-square difference of 2-6% compared to the Dobson and OMI measurements. We compare TANSO-FTS tropospheric ozone columns to those from ozonesonde data as well as from a three-dimensional chemical-climate model (MRI-CCM2). The TANSO-FTS data have high correlations with the ozonesonde data. The seasonal trends of the retrieved tropospheric ozone are consistent with those of the ozonesonde data. The spatial distribution of the tropospheric ozone from the TANSO-FTS and MRI-CCM2 shows good agreement, especially in the high-level tropospheric ozone regions. We also retrieve tropospheric H2O and HDO profiles simultaneously, accounting for the cross correlations between the water isotopes. The joint retrieval results in precise estimation of the isotope ratio by partial cancellation of systematic errors common to both H2O and HDO. The retrieved profiles and columns are compared with radiosonde, GPS, and ground-based high-resolution FTS data. The temporal and spatial variations of the precipitable water and the isotope ratio are consistent with those of the validation data. Finally, air pollutants such as CH3OH and NH3 are retrieved using the retrieved ozone and water vapor. We present the latitudinal and seasonal variations of CH3OH

Transforming a Fructan:Fructan 6G-Fructosyltransferase from Perennial Ryegrass into a Sucrose:Sucrose 1-Fructosyltransferase1[C

PubMed Central

Lasseur, Bertrand; Schroeven, Lindsey; Lammens, Willem; Le Roy, Katrien; Spangenberg, German; Manduzio, Hélène; Vergauwen, Rudy; Lothier, Jérémy; Prud'homme, Marie-Pascale; Van den Ende, Wim

2009-01-01

Fructosyltransferases (FTs) synthesize fructans, fructose polymers accumulating in economically important cool-season grasses and cereals. FTs might be crucial for plant survival under stress conditions in species in which fructans represent the major form of reserve carbohydrate, such as perennial ryegrass (Lolium perenne). Two FT types can be distinguished: those using sucrose (S-type enzymes: sucrose:sucrose 1-fructosyltransferase [1-SST], sucrose:fructan 6-fructosyltransferase) and those using fructans (F-type enzymes: fructan:fructan 1-fructosyltransferase [1-FFT], fructan:fructan 6G-fructosyltransferase [6G-FFT]) as preferential donor substrate. Here, we report, to our knowledge for the first time, the transformation of an F-type enzyme (6G-FFT/1-FFT) into an S-type enzyme (1-SST) using perennial ryegrass 6G-FFT/1-FFT (Lp6G-FFT/1-FFT) and 1-SST (Lp1-SST) as model enzymes. This transformation was accomplished by mutating three amino acids (N340D, W343R, and S415N) in the vicinity of the active site of Lp6G-FFT/1-FFT. In addition, effects of each amino acid mutation alone or in combination have been studied. Our results strongly suggest that the amino acid at position 343 (tryptophan or arginine) can greatly determine the donor substrate characteristics by influencing the position of the amino acid at position 340. Moreover, the presence of arginine-343 negatively affects the formation of neofructan-type linkages. The results are compared with recent findings on donor substrate selectivity within the group of plant cell wall invertases and fructan exohydrolases. Taken together, these insights contribute to our knowledge of structure/function relationships within plant family 32 glycosyl hydrolases and open the way to the production of tailor-made fructans on a larger scale. PMID:18952861

Incorporation of catalytic dehydrogenation into fischer-tropsch synthesis to significantly reduce carbon dioxide emissions

DOEpatents

Huffman, Gerald P.

2012-11-13

A new method of producing liquid transportation fuels from coal and other hydrocarbons that significantly reduces carbon dioxide emissions by combining Fischer-Tropsch synthesis with catalytic dehydrogenation is claimed. Catalytic dehydrogenation (CDH) of the gaseous products (C1-C4) of Fischer-Tropsch synthesis (FTS) can produce large quantities of hydrogen while converting the carbon to multi-walled carbon nanotubes (MWCNT). Incorporation of CDH into a FTS-CDH plant converting coal to liquid fuels can eliminate all or most of the CO.sub.2 emissions from the water-gas shift (WGS) reaction that is currently used to elevate the H.sub.2 level of coal-derived syngas for FTS. Additionally, the FTS-CDH process saves large amounts of water used by the WGS reaction and produces a valuable by-product, MWCNT.

Simulation of path delay multiplexing-based Fourier transform spectrometer for fiber Bragg grating interrogation.

PubMed

Chelliah, Pandian; Sahoo, Trilochan; Singh, Sheela; Sujatha, Annie

2015-10-20

A Fourier transform spectrometer (FTS) used for interrogating a fiber Bragg grating (FBG) consists of a scanning-type interferometer. The FTS has a broad wavelength range of operation and good multiplexing capability. However, it has poor wavelength resolution and interrogation speed. We propose a modification to the FTS using path delay multiplexing to improve the same. Using this method, spatial resolution and interrogation time can be improved by n times by using n path delays. In this paper, simulation results for n=2, 5 are shown.

Fourier-transform optical microsystems

NASA Technical Reports Server (NTRS)

Collins, S. D.; Smith, R. L.; Gonzalez, C.; Stewart, K. P.; Hagopian, J. G.; Sirota, J. M.

1999-01-01

The design, fabrication, and initial characterization of a miniature single-pass Fourier-transform spectrometer (FTS) that has an optical bench that measures 1 cm x 5 cm x 10 cm is presented. The FTS is predicated on the classic Michelson interferometer design with a moving mirror. Precision translation of the mirror is accomplished by microfabrication of dovetailed bearing surfaces along single-crystal planes in silicon. Although it is miniaturized, the FTS maintains a relatively high spectral resolution, 0.1 cm-1, with adequate optical throughput.

The total column of CO2 and CH4 measured with a compact Fourier transform spectrometer at NASA Armstrong Flight Research Center and Railroad Valley, Nevada, USA

NASA Astrophysics Data System (ADS)

Kawakami, S.; Shiomi, K.; Suto, H.; Kuze, A.; Hillyard, P. W.; Tanaka, T.; Podolske, J. R.; Iraci, L. T.; Albertson, R. T.

2014-12-01

The total columns of carbon dioxide (XCO2) and methane (XCH4) were measured with a compact Fourier transform spectrometer (FTS) at NASA Armstrong Flight Research Center (AFRC) and Railroad Valley, Nevada, USA (RRV) during a vicarious calibration campaign in June 2014. The campaign was performed to estimate changes in the radiometric response of the Thermal and Near Infrared Sensor for carbon Observations Fourier Transform Spectrometer (TANSO-FTS) and the Cloud and Aerosol Imager (TANSO-CAI) aboard Greenhouse gases Observing SATellite (GOSAT). TANSO-FTS measures spectra of radiance scattered by the Earth surface with high- and medium-gain depending on the surface reflectance. At high reflectance areas, such as deserts over north Africa and Australia, TANSO-FTS collects spectra with medium-gain. There was differences on atmospheric pressure and XCO2 retrieved from spectra obtained between high-gain and medium-gain. Because the retrieved products are useful for evaluating the difference of spectral qualities between high- and medium-gain, this work is an attempt to collect validation data for spectra with medium-gain of TANSO-FTS at remote and desert area with a compact and medium-spectral resolution instrument. As a compact FTS, EM27/SUN was used. It was manufactured and newly released on April 1, 2014 by Bruker. It is robust and operable in a high temperature environment. It was housed in a steel box to protect from dust and rain and powered by Solar panels. It can be operated by such a remote and desert area, like a RRV. Over AFRC and RRV, vertical profiles of CO2 and CH4 were measured using the Alpha Jet research aircraft as part of the Alpha Jet Atmospheric eXperiment (AJAX) of ARC, NASA. The values were calibrated to standard gases. To make the results comparable to WMO (World Meteorological Organization) standards, the retrieved XCO2 and XCH4 values are divided by a calibration factor. This values were determined by comparisons with in situ profiles measured by

Fast-track surgery improves postoperative clinical recovery and cellular and humoral immunity after esophagectomy for esophageal cancer.

PubMed

Chen, Lantao; Sun, Lixin; Lang, Yaoguo; Wu, Jun; Yao, Lei; Ning, Jinfeng; Zhang, Jinfeng; Xu, Shidong

2016-07-11

Our aim was to investigate the influence of FTS on human cellular and humoral immunity using a randomized controlled clinical study in esophageal cancer patients. Between October 2013 and December 2014, 276 patients with esophageal cancer in our department were enrolled in the study. The patients were randomized into two groups: FTS pathway group and conventional pathway group. The postoperative hospital stay, hospitalization expenditure, and postoperative complications were recorded. The markers of inflammatory and immune function were measured before operation as well as on the 1st, 3rd, and 7th postoperative days (POD), including serum level of interleukin-6 (IL-6), C-reactive protein (CRP), serum globulin, immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin A (IgA) and lymphocyte subpopulations (CD3 lymphocytes, CD4 lymphocytes, CD8 lymphocytes and the CD4/CD8 ratio) in the patients between the two groups. In all, 260 patients completed the study: 128 in the FTS group and 132 in the conventional group. We found implementation of FTS pathway decreases postoperative length of stay and hospital charges (P < 0.05). In addition, inflammatory reactions, based on IL-6 and CRP levels, were less intense following FTS pathway compared to conventional pathway on POD1 and POD3 (P < 0.05). On POD1 and POD3, the levels of IgG, IgA, CD3 lymphocytes, CD4 lymphocytes and the CD4/CD8 ratio in FTS group were significantly higher than those in control group (All P < 0.05). However, there were no differences in the level of IgM and CD8 lymphocytes between the two groups. FTS improves postoperative clinical recovery and effectively inhibited release of inflammatory factors via the immune system after esophagectomy for esophageal cancer. ChiCTR-TRC-13003562 , the date of registration: August 29, 2013.

Signal noise ratio analysis and on-orbit performance estimation of a solar occultation Fourier transform spectrometer

NASA Astrophysics Data System (ADS)

Li, Bicen; Xu, Pengmei; Hou, Lizhou; Wang, Caiqin

2017-10-01

Taking the advantages of high spectral resolution, high sensitivity and wide spectral coverage, space borne Fourier transform infrared spectrometer (FTS) plays more and more important role in atmospheric composition sounding. The combination of solar occultation and FTS technique improves the sensitivity of instrument. To achieve both high spectral resolution and high signal to noise ratio (SNR), reasonable allocation and optimization for instrument parameters are the foundation and difficulty. The solar occultation FTS (SOFTS) is a high spectral resolution (0.03 cm-1) FTS operating from 2.4 to 13.3 μm (750-4100cm-1), which will determine the altitude profile information of typical 10-100km for temperature, pressure, and the volume mixing ratios for several dozens of atmospheric compositions. As key performance of SOFTS, SNR is crucially important to high accuracy retrieval of atmospheric composition, which is required to be no less than 100:1 at the radiance of 5800K blackbody. Based on the study of various parameters and its interacting principle, according to interference theory and operation principle of time modulated FTS, a simulation model of FTS SNR has been built, which considers satellite orbit, spectral radiometric features of sun and atmospheric composition, optical system, interferometer and its control system, measurement duration, detector sensitivity, noise of detector and electronic system and so on. According to the testing results of SNR at the illuminating of 1000 blackbody, the on-orbit SNR performance of SOFTS is estimated, which can meet the mission requirement.

A prototype stationary Fourier transform spectrometer for near-infrared absorption spectroscopy.

PubMed

Li, Jinyang; Lu, Dan-feng; Qi, Zhi-mei

2015-09-01

A prototype stationary Fourier transform spectrometer (FTS) was constructed with a fiber-coupled lithium niobate (LiNbO3) waveguide Mach-Zehnder interferometer (MZI) for the purpose of rapid on-site spectroscopy of biological and chemical measurands. The MZI contains push-pull electrodes for electro-optic modulation, and its interferogram as a plot of intensity against voltage was obtained by scanning the modulating voltage from -60 to +60 V in 50 ms. The power spectrum of input signal was retrieved by Fourier transform processing of the interferogram combined with the wavelength dispersion of half-wave voltage determined for the MZI used. The prototype FTS operates in the single-mode wavelength range from 1200 to 1700 nm and allows for reproducible spectroscopy. A linear concentration dependence of the absorbance at λmax = 1451 nm for water in ethanolic solution was obtained using the prototype FTS. The near-infrared spectroscopy of solid samples was also implemented, and the different spectra obtained with different materials evidenced the chemical recognition capability of the prototype FTS. To make this prototype FTS practically applicable, work on improving its spectral resolution by increasing the maximum optical path length difference is in progress.

H∞ Robust Control of a Large-Piston MEMS Micromirror for Compact Fourier Transform Spectrometer Systems.

PubMed

Chen, Huipeng; Li, Mengyuan; Zhang, Yi; Xie, Huikai; Chen, Chang; Peng, Zhangming; Su, Shaohui

2018-02-08

Incorporating linear-scanning micro-electro-mechanical systems (MEMS) micromirrors into Fourier transform spectral acquisition systems can greatly reduce the size of the spectrometer equipment, making portable Fourier transform spectrometers (FTS) possible. How to minimize the tilting of the MEMS mirror plate during its large linear scan is a major problem in this application. In this work, an FTS system has been constructed based on a biaxial MEMS micromirror with a large-piston displacement of 180 μm, and a biaxial H∞ robust controller is designed. Compared with open-loop control and proportional-integral-derivative (PID) closed-loop control, H∞ robust control has good stability and robustness. The experimental results show that the stable scanning displacement reaches 110.9 μm under the H∞ robust control, and the tilting angle of the MEMS mirror plate in that full scanning range falls within ±0.0014°. Without control, the FTS system cannot generate meaningful spectra. In contrast, the FTS yields a clean spectrum with a full width at half maximum (FWHM) spectral linewidth of 96 cm -1 under the H∞ robust control. Moreover, the FTS system can maintain good stability and robustness under various driving conditions.

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

James K. Neathery; Gary Jacobs; Burtron H. Davis

In this reporting period, a fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of production since the reaction is highly exothermic. Consequently, heavy wax products must be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase FTS. The separation problem is further compounded by catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbonmore » particles. Existing pilot-scale equipment was modified to include a filtration test apparatus. After undergoing an extensive plant shakedown period, filtration tests with cross-flow filter modules using simulant FTS wax slurry were conducted. The focus of these early tests was to find adequate mixtures of polyethylene wax to simulate FTS wax. Catalyst particle size analysis techniques were also developed. Initial analyses of the slurry and filter permeate particles will be used by the research team to design improved filter media and cleaning strategies.« less

H∞ Robust Control of a Large-Piston MEMS Micromirror for Compact Fourier Transform Spectrometer Systems

PubMed Central

Li, Mengyuan; Zhang, Yi; Chen, Chang; Peng, Zhangming; Su, Shaohui

2018-01-01

Incorporating linear-scanning micro-electro-mechanical systems (MEMS) micromirrors into Fourier transform spectral acquisition systems can greatly reduce the size of the spectrometer equipment, making portable Fourier transform spectrometers (FTS) possible. How to minimize the tilting of the MEMS mirror plate during its large linear scan is a major problem in this application. In this work, an FTS system has been constructed based on a biaxial MEMS micromirror with a large-piston displacement of 180 μm, and a biaxial H∞ robust controller is designed. Compared with open-loop control and proportional-integral-derivative (PID) closed-loop control, H∞ robust control has good stability and robustness. The experimental results show that the stable scanning displacement reaches 110.9 μm under the H∞ robust control, and the tilting angle of the MEMS mirror plate in that full scanning range falls within ±0.0014°. Without control, the FTS system cannot generate meaningful spectra. In contrast, the FTS yields a clean spectrum with a full width at half maximum (FWHM) spectral linewidth of 96 cm−1 under the H∞ robust control. Moreover, the FTS system can maintain good stability and robustness under various driving conditions. PMID:29419765

The space station assembly phase: Flight telerobotic servicer feasibility. Volume 2: Methodology and case study

NASA Technical Reports Server (NTRS)

Smith, Jeffrey H.; Gyamfi, Max A.; Volkmer, Kent; Zimmerman, Wayne F.

1987-01-01

A methodology is described for examining the feasibility of a Flight Telerobotic Servicer (FTS) using two assembly scenarios, defined at the EVA task level, for the 30 shuttle flights (beginning with MB-1) over a four-year period. Performing all EVA tasks by crew only is compared to a scenario in which crew EVA is augmented by FTS. A reference FTS concept is used as a technology baseline and life-cycle cost analysis is performed to highlight cost tradeoffs. The methodology, procedure, and data used to complete the analysis are documented in detail.

Probing the cold and warm molecular gas in the Whirlpool Galaxy: Herschel SPIRE-FTS observations of the central region of M51 (NGC 5194)

NASA Astrophysics Data System (ADS)

Schirm, M. R. P.; Wilson, C. D.; Kamenetzky, J.; Parkin, T. J.; Glenn, J.; Maloney, P.; Rangwala, N.; Spinoglio, L.; Baes, M.; Boselli, A.; Cooray, A.; De Looze, I.; Fernández-Ontiveros, J. A.; Karczewski, O. Ł.; Wu, R.

2017-10-01

We present Herschel Spectral and Photometric Imaging Receiver (SPIRE)-Fourier Transform Spectrometer (FTS) intermediate-sampled mapping observations of the central ˜8 kpc (˜150 arcsec) of M51, with a spatial resolution of 40 arcsec. We detect four 12CO transitions (J = 4-3 to J = 7-6) and the [C I] 3P2-3P1 and 3P1-3P0 transitions. We supplement these observations with ground-based observations of 12CO J = 1-0 to J = 3-2 and perform a two-component non-local thermodynamic equilibrium analysis. We find that the molecular gas in the nucleus and centre regions has a cool component (Tkin ˜ 10-20 K) with a moderate but poorly constrained density (n(H2) ˜ 103-106 cm-3), as well as significant molecular gas in a warmer (Tkin ˜ 300-3000 K), lower density (n(H2) ˜ 101.6-102.5 cm-3) component. We compare our CO line ratios and calculated densities along with ratios of CO to total infrared luminosity to a grid of photon-dominated region (PDR) models and find that the cold molecular gas likely resides in PDRs with a field strength of G0 ˜ 102. The warm component likely requires an additional source of mechanical heating, from supernovae and stellar winds or possibly shocks produced in the strong spiral density wave. When compared to similar two-component models of other star-forming galaxies published as part of the Very Nearby Galaxies Survey (Arp 220, M82 and NGC 4038/39), M51 has the lowest density for the warm component, while having a warm gas mass fraction that is comparable to those of Arp 220 and M82, and significantly higher than that of NGC 4038/39.

Atomic-Scale Design of Iron Fischer-Tropsch Catalysts; A Combined Computational Chemistry, Experimental, and Microkinetic Modeling Approach

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

Manos Mavrikakis; James Dumesic; Rahul Nabar

2008-09-29

This work focuses on (1) searching/summarizing published Fischer-Tropsch synthesis (FTS) mechanistic and kinetic studies of FTS reactions on iron catalysts; (2) preparation and characterization of unsupported iron catalysts with/without potassium/platinum promoters; (3) measurement of H{sub 2} and CO adsorption/dissociation kinetics on iron catalysts using transient methods; (3) analysis of the transient rate data to calculate kinetic parameters of early elementary steps in FTS; (4) construction of a microkinetic model of FTS on iron, and (5) validation of the model from collection of steady-state rate data for FTS on iron catalysts. Three unsupported iron catalysts and three alumina-supported iron catalysts weremore » prepared by non-aqueous-evaporative deposition (NED) or aqueous impregnation (AI) and characterized by chemisorption, BET, temperature-programmed reduction (TPR), extent-of-reduction, XRD, and TEM methods. These catalysts, covering a wide range of dispersions and metal loadings, are well-reduced and relatively thermally stable up to 500-600 C in H{sub 2} and thus ideal for kinetic and mechanistic studies. Kinetic parameters for CO adsorption, CO dissociation, and surface carbon hydrogenation on these catalysts were determined from temperature-programmed desorption (TPD) of CO and temperature programmed surface hydrogenation (TPSR), temperature-programmed hydrogenation (TPH), and isothermal, transient hydrogenation (ITH). A microkinetic model was constructed for the early steps in FTS on polycrystalline iron from the kinetic parameters of elementary steps determined experimentally in this work and from literature values. Steady-state rate data were collected in a Berty reactor and used for validation of the microkinetic model. These rate data were fitted to 'smart' Langmuir-Hinshelwood rate expressions derived from a sequence of elementary steps and using a combination of fitted steady-state parameters and parameters specified from the transient

The ν_3 and ν_4 Bands of Nitric Acid (HNO_3) at 7.6 μm for Atmospheric Studies

NASA Astrophysics Data System (ADS)

Perrin, A.; Flaud, J. M.; Ridolfi, M.; Carlotti, M.

2012-06-01

Nitric acid (HNO_3) plays an important role as a reservoir molecule of the NO_x (nitrogen oxides) species in the stratosphere. The three strongest infrared bands of nitric acid are located at 11 μm (ν_5 and 2ν_9 bands), 7.6 μm (the ν_3 and ν_4 bands at 1326 and 1303 cm-1) and 5.8 μm (ν_2 band). Although two times weaker than those located at 7.6 and 5.8 μm, the 11 μm region is the only one which is used for nitric acid retrievals in the atmosphere by several satellite instruments like MIPAS (Michelson Interferometer for Passive Atmospheric Sounding on ENVISAT) or ACE-FTS (ACE Fourier transform spectrometer on SCISAT). This is because the available spectroscopic parameters for HNO_3 in the HITRAN and GEISA databases are of very good quality in this spectral region. Of the two remaining bands, the 7.6 μm one is only partly masked by water, and therefore can be used also for nitric acid retrievals in the upper stratosphere. Moreover, because of their large difference in band intensity, combining measurements at 11 μm and 7.6 μm could maximize informations on the vertical distribution of HNO_3 in the atmosphere. However at 7.6 μm the spectroscopic parameters available in the HITRAN and GEISA databases are are not so good. Indeed, these parameters originate from a list generated more than 20 years ago. The low quality of the list at 7.6 μm prevents HNO_3 retrievals and severely affects the retrievals of several species absorbing in the 7.5-7.7 μm region, like SO_2. This work is a new and more accurate investigation of the line positions and intensities for the ν_3 and ν_4 bands of nitric acid located at 1326.187 and 1303.074 cm-1). For this task, we used new infrared laboratory data combined with a new theoretical model. Examples showing substantial improvements will be given. [1] Rothman et al. J. Quant. Spectrosc. Radiat. Transf., 110, 533-572, 2009 [2] Jacquinet et al. J. Quant. Spectrosc. Radiat. Transf., 112, 2395-2445, 2011 [3] A. Perrin, O. Lado

Retrievals of carbonyl fluoride (COF2) from ACE-FTS and MIPAS spectra and their comparison with SLIMCAT CTM calculations

NASA Astrophysics Data System (ADS)

Harrison, Jeremy; Cai, Shaomin; Dudhia, Anu; Chipperfield, Martyn; Boone, Chris; Bernath, Peter

2014-05-01

Chemistry Experiment Fourier transform spectrometer (ACE-FTS), onboard the SCISAT-1 satellite, which has been recording atmospheric spectra since 2004, and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument onboard the ENVIronmental SATellite (Envisat), which has recorded thermal emission atmospheric spectra between 2002 and 2012. The observations are compared with the output of SLIMCAT, a state-of-the-art three-dimensional chemical transport model (CTM). The model aids in the interpretation of the COF2 satellite observations, and the comparison provides a validation of emission inventories and the atmospheric degradation reaction schemes used in the model.

A description of a staff development program: Preparing the elementary school classroom teacher to lead environmental field trips and to use an integrated subject approach to environmental education

NASA Astrophysics Data System (ADS)

Egana, John Joseph

This study of the Field Trip Specialist Program (FTS) described how a professional development plan fostered change in the traditional roles of third and fourth grade teachers. Teachers that volunteered were prepared to become interpretive guides for their class on environmental field trips, integrate their basic subject areas lessons into an environmental science context, and develop their self-perception as professional educators. This qualitative study made use of quantitative data and drew on information collected over four years from surveys, interviews, classroom observations, field trip and workshop observations, focus groups, journals and assessments performed in Florida. The FTS Program attracted teachers who thought it was important for all students to understand environmental issues, and these teachers believed in integrated instruction. These beliefs were inconsistent with many aspects of school culture. FTS invited the participation of these teachers and encouraged them to take control of the program by serving as instructors and program developers. Teachers described themselves as prepared to deliver the FTS Program with a high level of motivation and relevance. They also credited the program as beneficial in preparation for the Florida Comprehensive Assessment Tests (FCAT). Teachers reported that their responsibility as field trip leaders was the primary factor motivating them to provide conscientious presentation of pre- and post-field trip lessons and thorough integration of environmental topics in basic subject area instruction. Despite the impact of the field trip leadership factor, I could not find another program in the State of Florida that required teachers to lead their own field trips. Other influential factors specific to this program were: Voluntary participation, on-site field instruction, peer instructors and program developers, high quality and task specific materials, and pre- and post-assessments for students. Factors were identified

Comparison of preparation techniques for CoFeNb/CNTs catalyst

NASA Astrophysics Data System (ADS)

Hamid, Hami Haslinda; Zabidi, Noor Asmawati Mohd; Gholami, Zahra; Shaharun, Maizatul Shima

2016-11-01

CoFe-based catalysts were prepared using reverse-microemulsion and co-impregnation method. Effect of different preparation techniques on morphology and physiochemical properties of the FTS catalyst CoFeNb/CNTs was investigated. TEM analyses show that the morphological properties of catalysts were affected by preparation techniques. Reverse-micremulsion and co-impregnation method resulted in average particle size of 5.61 nm and 6.20 nm respectively. CoFe-impregnation catalyst is reducible at lower temperature compared to that of reverse-microemulsion catalyst. Acid and thermal treatment of CNTs created defects onto CNTs-support.

Adaptive Seat Energy Absorbers for Enhanced Crash Safety: Technology Demonstration

DTIC Science & Technology

2016-08-01

percentile male occupant and 21 ft/s crash velocity ............................................................................69 Fig. 78 Posttest ...34 ft/s crash velocity ............................................................................71 Fig. 82 Posttest photo for test no. 2, 50th...74 Fig. 86 Posttest photo for test no. 3, 50th percentile male occupant and 42

Astronomical imaging Fourier spectroscopy at far-infrared wavelengths

NASA Astrophysics Data System (ADS)

Naylor, David A.; Gom, Brad G.; van der Wiel, Matthijs H. D.; Makiwa, Gibion

2013-11-01

The principles and practice of astronomical imaging Fourier transform spectroscopy (FTS) at far-infrared wavelengths are described. The Mach–Zehnder (MZ) interferometer design has been widely adopted for current and future imaging FTS instruments; we compare this design with two other common interferometer formats. Examples of three instruments based on the MZ design are presented. The techniques for retrieving astrophysical parameters from the measured spectra are discussed using calibration data obtained with the Herschel–SPIRE instrument. The paper concludes with an example of imaging spectroscopy obtained with the SPIRE FTS instrument.

Fourier Transform Methods. Chapter 4

NASA Technical Reports Server (NTRS)

Kaplan, Simon G.; Quijada, Manuel A.

2015-01-01

This chapter describes the use of Fourier transform spectrometers (FTS) for accurate spectrophotometry over a wide spectral range. After a brief exposition of the basic concepts of FTS operation, we discuss instrument designs and their advantages and disadvantages relative to dispersive spectrometers. We then examine how common sources of error in spectrophotometry manifest themselves when using an FTS and ways to reduce the magnitude of these errors. Examples are given of applications to both basic and derived spectrophotometric quantities. Finally, we give recommendations for choosing the right instrument for a specific application, and how to ensure the accuracy of the measurement results..

Polarized Cell Division of Chlamydia trachomatis

PubMed Central

Abdelrahman, Yasser; Ouellette, Scot P.; Belland, Robert J.; Cox, John V.

2016-01-01

Bacterial cell division predominantly occurs by a highly conserved process, termed binary fission, that requires the bacterial homologue of tubulin, FtsZ. Other mechanisms of bacterial cell division that are independent of FtsZ are rare. Although the obligate intracellular human pathogen Chlamydia trachomatis, the leading bacterial cause of sexually transmitted infections and trachoma, lacks FtsZ, it has been assumed to divide by binary fission. We show here that Chlamydia divides by a polarized cell division process similar to the budding process of a subset of the Planctomycetes that also lack FtsZ. Prior to cell division, the major outer-membrane protein of Chlamydia is restricted to one pole of the cell, and the nascent daughter cell emerges from this pole by an asymmetric expansion of the membrane. Components of the chlamydial cell division machinery accumulate at the site of polar growth prior to the initiation of asymmetric membrane expansion and inhibitors that disrupt the polarity of C. trachomatis prevent cell division. The polarized cell division of C. trachomatis is the result of the unipolar growth and FtsZ-independent fission of this coccoid organism. This mechanism of cell division has not been documented in other human bacterial pathogens suggesting the potential for developing Chlamydia-specific therapeutic treatments. PMID:27505160

Delirium, Frailty, and Fast-Track Surgery in Oncogeriatrics: Is There a Link?

PubMed Central

Monacelli, Fiammetta; Signori, Alessio; Prefumo, Matteo; Giannotti, Chiara; Nencioni, Alessio; Romairone, Emanuele; Scabini, Stefano; Odetti, Patrizio

2018-01-01

Background/Aims Postoperative delirium (POD) is more frequent in elderly patients undergoing major cancer surgery. The interplay between individual clinical vulnerability and a series of perioperative factors seems to play a relevant role. Surgery is the first-line treatment option for cancer, and fast-track surgery (FTS) has been documented to decrease postoperative complications. The study sought to assess, after comprehensive geriatric assessment (CGA) and frailty stratification (Rockwood 40 items index), which perioperative parameters were predictive of POD development in elderly patients undergoing FTS for colorectal cancer. Methods A total of 107 consecutive subjects admitted for elective colorectal FTS were enrolled. All patients underwent CGA, frailly stratification, Timed up & go (TUG) test, 4AT test for delirium screening, anesthesiologists physical status classification, and Dindo-Clavien classification. Results The incidence of POD was 12.3%. Patients’ prevalent clinical phenotype was pre-frail. The multivariate analysis indicated physical performance (TUG in seconds) as the most significant predictor of POD for each second of increase. Conclusions Only few procedure-specific studies have examined the impact of FTS for colorectal cancer on POD. This is the first study to investigate the risk factors for POD, in a vulnerable octogenarian oncogeriatric population submitted to FTS surgery and frailty stratification. PMID:29515621

Results from the 2009 Michigan farm to school survey: participation grows from 2004.

PubMed

Colasanti, Kathryn J A; Matts, Colleen; Hamm, Michael W

2012-01-01

This study investigated changes in Michigan school food service directors' farm to school (FTS) participation levels and perspectives since a 2004 survey and factors that would facilitate FTS expansion. Electronic survey census of all Michigan school food service directors. Michigan kindergarten-12th grade schools. Food service directors of National School Lunch programs in Michigan. Survey respondents were asked about local food purchasing behaviors, interests, motivations, concerns, and barriers. Data were analyzed through descriptive statistics. Wilcoxon signed rank tests were calculated to compare 2004 and 2009 results. Participation in FTS was more than 3 times higher (41.5%) than in 2004 (10.6%), and the vast majority of school districts (77.0%) had taken at least 1 step to connect students with local food. Budget and cost issues were ranked higher as barriers to FTS than in 2004, but the desire to help Michigan farms had also substantially increased. Fresh and whole produce items were generally preferred for local procurement over frozen or canned items. Education to reverse perceived limits of procurement regulations, food safety assurances, and strategies to mitigate tight school food budgets are needed to encourage FTS expansion. Copyright © 2012 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Initial Results From the USNO Dispersed Fourier Transform Spectrograph

DTIC Science & Technology

2007-01-25

the full instrument bandpass. 5.2. k Andromedae and Geminorum To test whether the dFTS system can accurately detect RV variations in a stellar...prototype dFTS can measure stellar RVs with sufficient accuracy to find exoplanets. We also observed Andromedae (a three-planet system) and

MinCD cell division proteins form alternating co-polymeric cytomotive filaments

PubMed Central

Ghosal, Debnath; Trambaiolo, Daniel; Amos, Linda A.; Löwe, Jan

2014-01-01

Summary During bacterial cell division, filaments of the tubulin-like protein FtsZ assemble at midcell to form the cytokinetic Z-ring. Its positioning is regulated by the oscillation of MinCDE proteins. MinC is activated by MinD through an unknown mechanism and prevents Z-ring assembly anywhere but midcell. Here, using X-ray crystallography, electron microscopy and in vivo analyses we show that MinD activates MinC by forming a new class of alternating copolymeric filaments that show similarity to eukaryotic septin filaments A non-polymerising mutation in MinD causes aberrant cell division in E. coli. MinCD copolymers bind to membrane, interact with FtsZ, and are disassembled by MinE. Imaging a functional msfGFP-MinC fusion protein in MinE deleted cells reveals filamentous structures. EM imaging of our reconstitution of the MinCD-FtsZ interaction on liposome surfaces reveals a plausible mechanism for regulation of FtsZ ring assembly by MinCD copolymers. PMID:25500731

Platinum-Modulated Cobalt Nanocatalysts for Low-Temperature Aqueous-Phase Fischer Tropsch Synthesis

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

Wang, Hang; Zhou, Wu; Liu, JinXun

2013-01-01

Fischer Tropsch synthesis (FTS) is an important catalytic process for liquid fuel generation, which converts coal/shale gas/biomass-derived syngas (a mixture of CO and H2) to oil. While FTS is thermodynamically favored at low temperature, it is desirable to develop a new catalytic system that could allow working at a relatively low reaction temperature. In this article, we present a one-step hydrogenation reduction route for the synthesis of Pt Co nanoparticles (NPs) which were found to be excellent catalysts for aqueous-phase FTS at 433 K. Coupling with atomic-resolution scanning transmission electron microscopy (STEM) and theoretical calculations, the outstanding activity is rationalizedmore » by the formation of Co overlayer structures on Pt NPs or Pt Co alloy NPs. The improved energetics and kinetics from the change of the transition states imposed by the lattice mismatch between the two metals are concluded to be the key factors responsible for the dramatically improved FTS performance.« less

The effect of numbers of frozen-thawed boar sperm and addition of prostaglandin F2α at insemination on fertility in pigs.

PubMed

Knox, Robert V; Yantis, Brandon M

2014-12-30

Frozen-thawed boar sperm (FTS) has reduced fertility compared to liquid semen. Exogenous prostaglandin administered at insemination has been reported to improve cases of low fertility. This experiment tested the effect of number of FTS and addition of prostaglandin (PGF2α) on fertility. The experiment was performed in replicates using weaned sows (n=24) and synchronized gilts (n=94). All females were induced into estrus using PG600® at weaning or following estrus synchronization. At estrus, females received 0.5, 1.0, or 2 billion motile FTS (n=9 boars) with 0 or 5mg of PGF2α added into each AI dose at insemination. Inseminations occurred at 24 and 36h after onset of estrus and ovulation was monitored by ultrasound. Pregnancy and litter size were determined for sows at farrowing and d 50 of gestation for gilts at slaughter. There was no effect of PGF2α and no interaction with dose of FTS or parity on fertility (P>0.10). Pregnancy rate was affected by FTS dose (P<0.001) with 2.0×10(9) (76.3%) greater than 0.5×10(9) (46.2%) and 1.0×10(9) sperm (48.8±8.0%). Pregnancy rate was not affected by parity (P>0.10) but was influenced by boar (P<0.05). Number of fetuses was also affected by FTS dose (P<0.001) with 2.0×10(9) (10.1) and 1.0×10(9) (9.4) producing more pigs than 0.5×10(9) sperm (6.9±0.9). Litter size was also affected by parity (P=0.001) and boar (P<0.01). These results indicate that AI using 2.0×10(9) FTS can result in acceptable pregnancy rates and litter sizes but with no measurable benefit for addition of prostaglandin. Copyright © 2014 Elsevier B.V. All rights reserved.

A prodrug micellar carrier assembled from polymers with pendant farnesyl thiosalicylic acid moieties for improved delivery of paclitaxel.

PubMed

Sun, Jingjing; Chen, Yichao; Li, Ke; Huang, Yixian; Fu, Xiaofeng; Zhang, Xiaolan; Zhao, Wenchen; Wei, Yuan; Xu, Liang; Zhang, Peijun; Venkataramanan, Raman; Li, Song

2016-10-01

In order to achieve enhanced and synergistic delivery of paclitaxel (PTX), a hydrophobic anticancer agent, two novel prodrug copolymers, POEG15-b-PFTS6 and POEG15-b-PFTS16 composed of hydrophilic poly(oligo(ethylene glycol) methacrylate) (POEG) and hydrophobic farnesylthiosalicylate (FTS, a nontoxic Ras antagonist) blocks, were synthesized. Both POEG-b-PFTS polymers were able to form micelles with intrinsic antitumor activity in vitro and in vivo. Employing these micelles as a carrier to load PTX, their drug loading capacity, stability, in vivo biodistribution and tumor inhibition effect were evaluated. PTX/POEG15-b-PFTS16 mixed micelles exhibited an excellent stability of 9days at 4°C with a PTX loading capacity of 8.2%, which was more effective than PTX/POEG15-b-PFTS6 mixed micelles. In vivo biodistribution data showed that DiR-loaded POEG-b-PFTS micelles were more effectively localized in the tumor than in other organs. Moreover, both PTX/POEG-b-PFTS micelles showed significantly higher antitumor activity than Taxol in a 4T1.2 murine breast tumor model, and the tumor inhibition and animal survival followed the order of PTX/POEG15-b-PFTS16>PTX/POEG15-b-PFTS6>POEG15-b-PFTS16>Taxol≈POEG15-b-PFTS6. Our data suggest that POEG-b-PFTS micelles are a promising anticancer drug carrier that warrants more studies in the future. Polymerization of drug-based monomer represents a facile and precise method to obtain well-defined polymeric prodrug amphiphiles. Currently, most reports largely focus on the synthesis methods and the biophysical properties. There is limited information about their anti-tumor activity and delivery function as prodrug carriers in vitro and in vivo. In this manuscript, we report the development of two novel prodrug copolymers, POEG15-b-PFTS6 and POEG15-b-PFTS16 composed of hydrophilic poly(oligo(ethylene glycol) methacrylate) (POEG) and hydrophobic farnesylthiosalicylate (FTS, a nontoxic Ras antagonist) blocks. Both POEG-b-PFTS polymers were able

Results from the 2009 Michigan Farm to School Survey: Participation Grows from 2004

ERIC Educational Resources Information Center

Colasanti, Kathryn J. A.; Matts, Colleen; Hamm, Michael W.

2012-01-01

Objective: This study investigated changes in Michigan school food service directors' farm to school (FTS) participation levels and perspectives since a 2004 survey and factors that would facilitate FTS expansion. Design: Electronic survey census of all Michigan school food service directors. Setting: Michigan kindergarten-12th grade schools.…

Rare earth elements geochemistry in springs from Taftan geothermal area SE Iran

NASA Astrophysics Data System (ADS)

Shakeri, Ata; Ghoreyshinia, Sayedkazem; Mehrabi, Behzad; Delavari, Morteza

2015-10-01

Concentrations of rare earth elements (REEs) were determined in springs and andesitic-dacitic rocks of Taftan geothermal field. Hydrochemical results of major ions indicate that thermal springs are Na-SO4-Cl and Ca-SO4-Cl types. Concentrations of REEs are in ranges of 10- 4 to 1.2 and 49 to 62 times of chondrite for springwater and rock samples, respectively. The thermal (STS and TTS) and the cold (APS) springs with low pH values exhibit a very high REE contents (0.64 to 3.15 mg/l). Saturation index indicates that Fe and Al phases can control dissolved REE concentration in FTS and PF cold springs. The speciation of REE complexes indicates dominant presence of LnSO4+ and free ion in the Taftan thermal springs. In APS cold spring with pH 4, fluoride complexes are dominate over the free ion and sulfate species, while in PF and FTS cold springs with pH 6.4 and 7, respectively, carbonate complexes (LnCO3+) are predominant species. Chondrite-normalized pattern for the low-pH waters show very distinctive gull-wing patterns, characteristic feature of acid-sulfate geothermal systems, and are similar to those of the host rocks. Chemical characteristics of rare earth elements in spring and volcanic rock samples indicate that REEs are originated from the andesitic-dacitic host rocks. Whole-rock-normalized REE patterns and petrographic evidences show that rare earth elements leached mainly from marginal alteration of minerals and matrix decomposition in volcanic rocks. In chondrite-normalized REE patterns, significant negative Eu anomaly in the cold springs compare to the thermal and acidic springs indicates that alteration of plagioclase is more intense in the later, corresponding to increasing in temperature and acidic state of reactant water.

Incomplete proteasomal degradation of green fluorescent proteins in the context of tandem fluorescent protein timers

PubMed Central

Khmelinskii, Anton; Meurer, Matthias; Ho, Chi-Ting; Besenbeck, Birgit; Füller, Julia; Lemberg, Marius K.; Bukau, Bernd; Mogk, Axel; Knop, Michael

2016-01-01

Tandem fluorescent protein timers (tFTs) report on protein age through time-dependent change in color, which can be exploited to study protein turnover and trafficking. Each tFT, composed of two fluorescent proteins (FPs) that differ in maturation kinetics, is suited to follow protein dynamics within a specific time range determined by the maturation rates of both FPs. So far, tFTs have been constructed by combining slower-maturing red fluorescent proteins (redFPs) with the faster-maturing superfolder green fluorescent protein (sfGFP). Toward a comprehensive characterization of tFTs, we compare here tFTs composed of different faster-maturing green fluorescent proteins (greenFPs) while keeping the slower-maturing redFP constant (mCherry). Our results indicate that the greenFP maturation kinetics influences the time range of a tFT. Moreover, we observe that commonly used greenFPs can partially withstand proteasomal degradation due to the stability of the FP fold, which results in accumulation of tFT fragments in the cell. Depending on the order of FPs in the timer, incomplete proteasomal degradation either shifts the time range of the tFT toward slower time scales or precludes its use for measurements of protein turnover. We identify greenFPs that are efficiently degraded by the proteasome and provide simple guidelines for the design of new tFTs. PMID:26609072

Farm to School Programs in Pennsylvania

ERIC Educational Resources Information Center

Hinrichs, Clare; Schafft, Kai

2008-01-01

Farm to school (FTS) programs have been getting more and more attention these days. FTS programs aim to increase the supply of fresh, locally grown farm products served for meals and snacks in K-12 school environments, and tend to incorporate educational and experiential components designed to increase students' understanding of and engagement…

The Role of Social Cognitive Theory in Farm-to-School-Related Activities: Implications for Child Nutrition

ERIC Educational Resources Information Center

Berlin, Linda; Norris, Kimberly; Kolodinsky, Jane; Nelson, Abbie

2013-01-01

Background: Farm-to-school (FTS) programs are gaining attention for many reasons, one of which is the recognition that they could help stem the increase in childhood overweight and obesity. Most FTS programs that have been evaluated have increased students' selection or intake of fruits and vegetables following the incorporation of FTS…

β-Lactam resistance among Haemophilus influenzae isolates in Poland.

PubMed

Kiedrowska, Marlena; Kuch, Alicja; Żabicka, Dorota; Waśko, Izabela; Ronkiewicz, Patrycja; Wasiak, Katarzyna; Bojarska, Katarzyna; Hryniewicz, Waleria; Skoczyńska, Anna

2017-12-01

Haemophilus influenzae is a human-specific Gram-negative coccobacillus responsible for a significant number of respiratory tract infections and severe invasive infections such as meningitis and sepsis. The purpose of this study was to characterise the mechanisms of β-lactam resistance among Polish H. influenzae isolates and to evaluate the resistance detection methods applied. This study was conducted on 117 Polish H. influenzae isolates collected in 2012. Minimum inhibitory concentrations were assessed by broth microdilution. All strains were evaluated using the disk diffusion method and the algorithm proposed by the Nordic Committee on Antimicrobial Susceptibility Testing (NordicAST). To detect changes in penicillin-binding protein 3 (PBP3), PCR screening was performed, followed by ftsI gene sequencing. Neither β-lactamase production nor PBP3 alterations were demonstrated in 76 isolates (65.0%). Susceptibility to ampicillin, amoxicillin, amoxicillin/clavulanic acid, cefuroxime (intravenous) and ceftriaxone was observed in 70.9%, 78.6%, 98.3%, 82.9% and 100% of the isolates, respectively. β-Lactamase production characterised 21 isolates (17.9%). Screening PCR identified 20 isolates (17.1%) with PBP3 alterations, and according to subsequent ftsI sequencing all these strains were finally recognised as gBLNAR (genetically β-lactamase-negative, ampicillin-resistant), among which 65.0% were ampicillin-resistant. According to molecular classification of PBP3 alterations, 95.0% of gBLNAR belonged to group II, representing four subgroups IIa-IId. Haemophilus influenzae resistance to antibiotics requires continuous attention, effective detection methods and a rational policy of antibiotic usage. The algorithm proposed by NordicAST can be applied in routine laboratory work, whereas sequencing of the ftsI gene may be useful in molecular epidemiology studies. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All

Bacterial Actins.

PubMed

Izoré, Thierry; van den Ent, Fusinita

2017-01-01

A diverse set of protein polymers, structurally related to actin filaments contributes to the organization of bacterial cells as cytomotive or cytoskeletal filaments. This chapter describes actin homologs encoded by bacterial chromosomes. MamK filaments, unique to magnetotactic bacteria, help establishing magnetic biological compasses by interacting with magnetosomes. Magnetosomes are intracellular membrane invaginations containing biomineralized crystals of iron oxide that are positioned by MamK along the long-axis of the cell. FtsA is widespread across bacteria and it is one of the earliest components of the divisome to arrive at midcell, where it anchors the cell division machinery to the membrane. FtsA binds directly to FtsZ filaments and to the membrane through its C-terminus. FtsA shows altered domain architecture when compared to the canonical actin fold. FtsA's subdomain 1C replaces subdomain 1B of other members of the actin family and is located on the opposite side of the molecule. Nevertheless, when FtsA assembles into protofilaments, the protofilament structure is preserved, as subdomain 1C replaces subdomain IB of the following subunit in a canonical actin filament. MreB has an essential role in shape-maintenance of most rod-shaped bacteria. Unusually, MreB filaments assemble from two protofilaments in a flat and antiparallel arrangement. This non-polar architecture implies that both MreB filament ends are structurally identical. MreB filaments bind directly to membranes where they interact with both cytosolic and membrane proteins, thereby forming a key component of the elongasome. MreB filaments in cells are short and dynamic, moving around the long axis of rod-shaped cells, sensing curvature of the membrane and being implicated in peptidoglycan synthesis.

The Geostationary Fourier Transform Spectrometer

NASA Technical Reports Server (NTRS)

Key, Richard; Sander, Stanley; Eldering, Annmarie; Miller, Charles; Frankenberg, Christian; Natra, Vijay; Rider, David; Blavier, Jean-Francois; Bekker, Dmitriy; Wu, Yen-Hung

2012-01-01

The Geostationary Fourier Transform Spectrometer (GeoFTS) is an imaging spectrometer designed for an earth science mission to measure key atmospheric trace gases and process tracers related to climate change and human activity. The GeoFTS instrument is a half meter cube size instrument designed to operate in geostationary orbit as a secondary "hosted" payload on a commercial geostationary satellite mission. The advantage of GEO is the ability to continuously stare at a region of the earth, enabling frequent sampling to capture the diurnal variability of biogenic fluxes and anthropogenic emissions from city to continental scales. The science goal is to obtain a process-based understanding of the carbon cycle from simultaneous high spatial resolution measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and chlorophyll fluorescence (CF) many times per day in the near infrared spectral region to capture their spatial and temporal variations on diurnal, synoptic, seasonal and interannual time scales. The GeoFTS instrument is based on a Michelson interferometer design with a number of advanced features incorporated. Two of the most important advanced features are the focal plane arrays and the optical path difference mechanism. A breadboard GeoFTS instrument has demonstrated functionality for simultaneous measurements in the visible and IR in the laboratory and subsequently in the field at the California Laboratory for Atmospheric Remote Sensing (CLARS) observatory on Mt. Wilson overlooking the Los Angeles basin. A GeoFTS engineering model instrument is being developed which will make simultaneous visible and IR measurements under space flight like environmental conditions (thermal-vacuum at 180 K). This will demonstrate critical instrument capabilities such as optical alignment stability, interferometer modulation efficiency, and high throughput FPA signal processing. This will reduce flight instrument development risk and show that the GeoFTS

Submittal for 2003 Project of the Year K Basins Fuel Transfer System Project

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

GERBER, M.S.

2003-01-29

Fluor Hanford, Inc. is pleased to submit the K Basins Fuel Transfer System (FTS) for consideration by the Project Management Institute as Project of the Year for 2003. The FTS involved installing a unique, unproven system in an inhospitable and deteriorating radiological and hazardous environment, under very stringent requirements and within an extremely condensed schedule, just 19 months, from authorization to full operations. The FTS, therefore, is an excellent example of effective project management, and the dynamic involvement of an integrated team representing a broad spectrum of personnel, disciplines, and services. The FTS is an integral and critical part ofmore » a larger project at Hanford -the Spent Nuclear Fuel Project (SNF). The mission of the SNF Project is to relocate used, or spent, nuclear fuel to safe interim storage, permanently dispose of radioactive debris in the K-Basins, and deactivate all related facilities and prepare them for demolition. Today, the FTS is being used to remove highly radioactive nuclear fuel from an aging, and potentially unstable storage in underground pools of water--the K-Basins--and safely transport it to a processing area to be cleaned, dried and sent to safe storage. The role the FTS plays in successfully completing the mission of the SNF Project is concrete evidence of the intrinsic value of project management and a testimonial to the innovation, ingenuity, and teamwork of many--from workers to management and subcontractors, and regulators to stakeholders. It's a true success story and one that will have a happy ending, safely eliminating the risk of potentially contaminating one of Washington state's most valuable natural resources, the Columbia River. This nomination is dedicated to that Project Team.« less

Forest fuel treatment detection using multi-temporal airborne lidar data and high-resolution aerial imagery: a case study in the Sierra Nevada Mountains, California

Treesearch

Yanjun Su; Qinghua Guo; Brandon M. Collins; Danny L. Fry; Tianyu Hu; Maggi Kelly

2016-01-01

Treatments to reduce forest fuels are often performed in forests to enhance forest health, regulate stand density, and reduce the risk of wildfires. Although commonly employed, there are concerns that these forest fuel treatments (FTs) may have negative impacts on certain wildlife species. Often FTs are planned across large landscapes, but the actual treatment extents...

Reconnaissance Report for Hydropower, Lock and Dam Number 2, Mississippi River.

DTIC Science & Technology

1981-09-01

these power values, please contact Mr. David Simon of my staff at (FTS) 353-6701 and he will assist you. Sincerely, •n F. Coffill, P.E. Regional...in our April 13, 1981 letter to you. If you have any questions regarding these power values, please contact Mr. David Simon of my staff at (FTS) 353

Progress status of the GOSAT and GOSAT-2 SWIR L2 products

NASA Astrophysics Data System (ADS)

Yoshida, Y.; Oshio, H.; Kamei, A.; Morino, I.; Uchino, O.; Saito, M.; Noda, H.; Matsunaga, T.

2017-12-01

The Greenhouse gases Observing SATellite (GOSAT) has been operating for more than eight years, and the column-averaged dry air mole fractions of carbon dioxide, methane, and water vapor (XCO2, XCH4, and XH2O; hereafter called Xgas) have been retrieved globally from the Short-Wavelength InfraRed (SWIR) spectral data (0.76 μm, 1.6 μm, and 2.0 μm bands) observed with Thermal And Near-infrared Sensor for carbon Observation Fourier Transform Spectrometer (TANSO-FTS) onboard GOSAT. Xgas are simultaneously retrieved using a so-called full-physics retrieval method. The retrieval results are released as the FTS SWIR L2 product and available via GOSAT Data Archive Service (GDAS; https://data2.gosat.nies.go.jp/). During the TANSO-FTS operation, several issues were found, and some of them made small changes to the characteristics of the spectral data. Therefore, current SWIR L2 product has several minor versions as V02.xx to distinguish possible retrieval quality difference. To provide long-term uniform quality spectra, JAXA reprocessed whole spectral data as FTS L1B V201.202. We have been re-evaluating the characteristics of the new spectral data, and results will be reflected to the next major version up of the SWIR L2 products (V03). As a successor mission to the GOSAT, GOSAT-2 is planned to be launched in FY2018. According to the latest design of the TANSO-FTS-2 (FTS onboard the GOSAT-2), its SNR is higher than or almost equal to the TANSO-FTS, and its spectral range is expanded to cover the 2.3 μm carbon monoxide (CO) band. The SWIR L2 retrieval algorithm for GOSAT-2 is developing based on the latest retrieval algorithm for GOSAT. Our preliminary sensitivity test based on the designed specification shows that the SNR improvement in SWIR bands reduces the retrieval random error (precision) about 15% for XCO2 and 35% for XCH4 than those of GOSAT. In addition to the full-physics based XCO2, XCH4, XH2O, and XCO products, we are planning to provide the proxy-based XCH4

Chlamydia co-opts the rod shape-determining proteins MreB and Pbp2 for cell division.

PubMed

Ouellette, Scot P; Karimova, Gouzel; Subtil, Agathe; Ladant, Daniel

2012-07-01

Chlamydiae are obligate intracellular bacterial pathogens that have extensively reduced their genome in adapting to the intracellular environment. The chlamydial genome contains only three annotated cell division genes and lacks ftsZ. How this obligate intracellular pathogen divides is uncharacterized. Chlamydiae contain two high-molecular-weight (HMW) penicillin binding proteins (Pbp) implicated in peptidoglycan synthesis, Pbp2 and Pbp3/FtsI. We show here, using HMW Pbp-specific penicillin derivatives, that both Pbp2 and Pbp3 are essential for chlamydial cell division. Ultrastructural analyses of antibiotic-treated cultures revealed distinct phenotypes: Pbp2 inhibition induced internal cell bodies within a single outer membrane whereas Pbp3 inhibition induced elongated phenotypes with little internal division. Each HMW Pbp interacts with the Chlamydia cell division protein FtsK. Chlamydiae are coccoid yet contain MreB, a rod shape-determining protein linked to Pbp2 in bacilli. Using MreB-specific antibiotics, we show that MreB is essential for chlamydial growth and division. Importantly, co-treatment with MreB-specific and Pbp-specific antibiotics resulted in the MreB-inhibited phenotype, placing MreB upstream of Pbp function in chlamydial cell division. Finally, we showed that MreB also interacts with FtsK. We propose that, in Chlamydia, MreB acts as a central co-ordinator at the division site to substitute for the lack of FtsZ in this bacterium. © 2012 Blackwell Publishing Ltd.

Compact liquid crystal waveguide based fourier transform spectrometer for in-situ and remote gas and chemical sensing

NASA Astrophysics Data System (ADS)

Chao, Tien-Hsin; Davis, Scott R.; Rommel, Scott D.; Farca, George; Luey, Ben; Martin, Alan; Anderson, Michael H.

2009-11-01

Jet Propulsion Lab and Vescent Photonics Inc. are jointly developing an innovative ultra-compact (volume < 10 cm3), ultra-low power (<10-3 Watt-hours per measurement and zero power consumption when not measuring), completely nonmechanical electro-optic Fourier transform spectrometers (EO-FTS) that will be suitable for a variety of remoteplatform, in-situ measurements. This EO-FTS consists of: i) a novel electro-evanescent waveguide architecture as the solid-state time delay device whose optical path difference (OPD) can be precisely varied utilizing voltage control, ii) a photodetector diode, and iii) an external light/sample collecting devices tailored for either in-situ gas and/or rock sample analysis or for remote atmospheric gas analysis. These devices are made possible by a novel electro-evanescent waveguide architecture, enabling "chip-scale" EO-FTS sensors. The potential performance of these EO-FTS sensors include: i) a spectral range throughout 0.4-5 μm (25000 - 2000 cm-1), ii) high-resolution ▵λ <= 0.1 nm), iii) high-speed (< 1 ms) measurements, and iv) rugged integrated optical construction. This performance potential enables the detection and quantification of a large number of different atmospheric gases simultaneously in the same air mass and the rugged construction will enable deployment on previously inaccessible platforms. In this paper, the up-to-date EO-FTS sensor development status will be presented; initial experimental results will also be demonstrated.

Bacillus subtilis Intramembrane Protease RasP Activity in Escherichia coli and In Vitro.

PubMed

Parrell, Daniel; Zhang, Yang; Olenic, Sandra; Kroos, Lee

2017-10-01

RasP is a predicted intramembrane metalloprotease of Bacillus subtilis that has been proposed to cleave the stress response anti-sigma factors RsiW and RsiV, the cell division protein FtsL, and remnant signal peptides within their transmembrane segments. To provide evidence for direct effects of RasP on putative substrates, we developed a heterologous coexpression system. Since expression of catalytically inactive RasP E21A inhibited expression of other membrane proteins in Escherichia coli , we added extra transmembrane segments to RasP E21A, which allowed accumulation of most other membrane proteins. A corresponding active version of RasP appeared to promiscuously cleave coexpressed membrane proteins, except those with a large periplasmic domain. However, stable cleavage products were not observed, even in clpP mutant E. coli Fusions of transmembrane segment-containing parts of FtsL and RsiW to E. coli maltose-binding protein (MBP) also resulted in proteins that appeared to be RasP substrates upon coexpression in E. coli , including FtsL with a full-length C-terminal domain (suggesting that prior cleavage by a site 1 protease is unnecessary) and RsiW designed to mimic the PrsW site 1 cleavage product (suggesting that further trimming by extracytoplasmic protease is unnecessary). Purified RasP cleaved His 6 -MBP-RsiW(73-118) in vitro within the RsiW transmembrane segment based on mass spectrometry analysis, demonstrating that RasP is an intramembrane protease. Surprisingly, purified RasP failed to cleave His 6 -MBP-FtsL(23-117). We propose that the lack of α-helix-breaking residues in the FtsL transmembrane segment creates a requirement for the membrane environment and/or an additional protein(s) in order for RasP to cleave FtsL. IMPORTANCE Intramembrane proteases govern important signaling pathways in nearly all organisms. In bacteria, they function in stress responses, cell division, pathogenesis, and other processes. Their membrane-associated substrates are

Operational Readiness Review Final Report for K Basin Fuel Transfer System

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

DAVIES, T.H.

2002-10-01

An Operational Readiness Review (ORR) was conducted by the U.S. Department of Energy (DOE), Richland Operations Office (RL) to verify that an adequate state of readiness had been achieved for startup of the K Basin Fuel Transfer System (FTS). The DOE ORR was conducted during the period November 6-18, 2002. The DOE ORR team concluded that the K Basin Fuel Transfer System is ready to start operations, subject to completion and verification of identified pre-start findings. The ORR was conducted in accordance with the Spent Nuclear Fuel (SNF) K Basin Fuel Transfer System (FTS) Operational Readiness Review (ORR) Plan ofmore » Action and the Operational Readiness Review Implementation Plan for K Basin Fuel Transfer System. Review activities consisted of staff interviews, procedure and document reviews, and observations of normal facility operations, operational upset conditions, and an emergency drill. The DOE ORR Team also reviewed and assessed the adequacy of the contractor ORR3 and the RL line management review. The team concurred with the findings and observations identified in these two reports. The DOE ORR for the FTS evaluated the contractor under single-shift operations. Of concern to the ORR Team was that SNF Project management intended to change from a single-shift FTS operation to a two-shift operation shortly after the completion of the DOE ORR. The ORR team did not assess two-shift FTS operations and the ability of the contractor to conduct a smooth transition from shift to shift. However, the DOE ORR team did observe an operational upset drill that was conducted during day shift and carried over into swing shift; during this drill, swing shift was staffed with fewer personnel as would be expected for two-shift operations. The facility was able to adequately respond to the event with the reduced level of staff. The ORR Team was also able to observe a Shift Manager turnover meeting when one shift manager had to be relieved during the middle of the day. The

Perfluorinated and polyfluorinated compounds in lake food webs from the Canadian high Arctic.

PubMed

Lescord, Gretchen L; Kidd, Karen A; De Silva, Amila O; Williamson, Mary; Spencer, Christine; Wang, Xiaowa; Muir, Derek C G

2015-03-03

Per- and polyfluorinated alkyl substances (PFASs) enter Arctic lakes through long-range atmospheric transport and local contamination, but their behavior in aquatic food webs at high latitudes is poorly understood. This study compared the concentrations of perfluorocarboxylates, perfluorosulfonates, and fluorotelomer sulfonates (FTS) in biotic and abiotic samples from six high Arctic lakes near Resolute Bay, Nunavut, Canada. Two of these lakes are known to be locally contaminated by a small airport and Arctic char (Salvelinus alpinus) from these lakes had over 100 times higher total [PFAS] when compared to fish from neighboring lakes. Perfluorononanoate (PFOA) and perfluorooctanesulfonate (PFOS) dominated in char, benthic chironomids (their main prey), and sediments, while pelagic zooplankton and water were dominated by lower chain acids and perfluorodecanesulfonate (PFDS). This study also provides the first measures of perfluoroethylcyclohexanesulfonate (PFECHS) and FTS compounds in water, sediment, juvenile char, and benthic invertebrates from lakes in the high Arctic. Negative relationships between [PFAS] and δ(15)N values (indicative of trophic position) within these food webs indicated no biomagnification. Overall, these results suggest that habitat use and local sources of contamination, but not trophic level, are important determinants of [PFAS] in biota from freshwater food webs in the Canadian Arctic.

Effect of steam during Fischer–Tropsch Synthesis using biomass-derived syngas

Treesearch

Zi Wang; Khiet Mai; Nitin Kumar; Thomas Elder; Leslie H. Groom; James J. Spivey

2017-01-01

Fischer–Tropsch synthesis (FTS) with biomass- derived syngas was performed using both iron-based 100Fe/6Cu/4K/25Al catalyst and ruthenium-based 5 % Ru/SiO2 catalyst. During FTS, different concentrations of steam were co-fed with the biomass-derived syngas to promote the water gas shift reaction and increase the H2/ CO ratio...

Optical alignment of high resolution Fourier transform spectrometers

NASA Technical Reports Server (NTRS)

Breckinridge, J. B.; Ocallaghan, F. G.; Cassie, A. G.

1980-01-01

Remote sensing, high resolution FTS instruments often contain three primary optical subsystems: Fore-Optics, Interferometer Optics, and Post, or Detector Optics. We discuss the alignment of a double-pass FTS containing a cat's-eye retro-reflector. Also, the alignment of fore-optics containing confocal paraboloids with a reflecting field stop which relays a field image onto a camera is discussed.

[Studies on interaction of acid-treated nanotube titanic acid and amino acids].

PubMed

Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang

2010-06-01

Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

Hydrologic effects of proposed changes in management practices, Winnebago Pool, Wisconsin

USGS Publications Warehouse

Krug, William R.

1981-01-01

In addition, the study illustrated that the discharge from the Winnebago pool could be managed to guarantee that the discharge in the Fox River downstream would not fall below a specified discharge up to 1,500 ft^/s. In most years this would have no effect on the stage of the pool. In a few years there would be a conflict between releasing water from the pool to maintain the desired discharge and maintaining water levels above the required minimum stage. The frequency of this possible conflict varies with the level of discharge desired in the Fox River from 1 year in 60 for a discharge of 1,100 ft^/s to about 1 year in 15 for a discharge of 1,500 ft^/s.

Automation and robotics and related technology issues for Space Station customer servicing

NASA Technical Reports Server (NTRS)

Cline, Helmut P.

1987-01-01

Several flight servicing support elements are discussed within the context of the Space Station. Particular attention is given to the servicing facility, the mobile servicing center, and the flight telerobotic servicer (FTS). The role that automation and robotics can play in the design and operation of each of these elements is discussed. It is noted that the FTS, which is currently being developed by NASA, will evolve to increasing levels of autonomy to allow for the virtual elimination of routine EVA. Some of the features of the FTS will probably be: dual manipulator arms having reach and dexterity roughly equivalent to that of an EVA-suited astronaut, force reflection capability allowing efficient teleoperation, and capability of operating from a variety of support systems.

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

Amitava Sarkar; James K. Neathery; Burtron H. Davis

A fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of operation since the reaction is highly exothermic. Consequently, heavy wax products in one approach may be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase iron-based FTS and is a key factor for optimizing operating costs. The separation problem is further compounded by attrition of ironmore » catalyst particles and the formation of ultra-fine particles.« less

A Fourier transform spectrometer for site testing at Dome A

NASA Astrophysics Data System (ADS)

Li, Xin-Xing; Paine, Scott; Yao, Qi-Jun; Shi, Sheng-Cai; Matsuo, Hiroshi; Yang, Ji; Zhang, Qi-Zhou

2009-07-01

Observations in tera-hertz astronomy can only be done at a site with good atmospheric transmission at millimeter and submillimeter wavelengths. With extremely dry weather and calm atmosphere resulted by high altitude and cold temperature, Dome A (or Dome Argus), Antarctica, is possibly the best site on this earth for THz astronomy. To evaluate the site condition there, we are constructing a Fourier Transform Spectrometer (FTS) based on Martin-Puplett interferometer to measure the atmospheric transmission in the frequency range of 0.75~15THz. The whole FTS system is designed for unattended and outdoor (temperatures even below -70 degrees Celsius) operation. Its total power consumption is estimated to be approximately 200W. This contribution will give a brief overview of this FTS development.

JPSS Science Data Services for the Direct Readout Community

NASA Technical Reports Server (NTRS)

Chander, Gyanesh; Lutz, Bob

2014-01-01

The Suomi National Polar-orbiting Partnership (S-NPP) and Joint Polar Satellite System (JPSS) High Rate Data (HRD) link provides Direct Broadcast data to users in real-time, utilizing their own remote field terminals. The Field Terminal Support (FTS) provides the resources needed to support the Direct Readout communities by providing software, documentation, and periodic updates to enable them to produce data products from SNPP and JPSS. The FTS distribution server will also provide the necessary ancillary and auxiliary data needed for processing the broadcasts, as well as making orbital data available to assist in locating the satellites of interest. In addition, the FTS provides development support for the algorithm and software through GSFC Direct Readout Laboratory (DRL) International Polar Orbiter Processing Package (IPOPP) and University of Wisconsin (UWISC) Community Satellite Processing Package (CSPP), to enable users to integrate the algorithms into their remote terminals. The support the JPSS Program provides to the institutions developing and maintaining these two software packages, will demonstrate the ability to produce ready-to-use products from the HRD link and provide risk reduction effort at a minimal cost. This paper discusses the key functions and system architecture of FTS.

Sufficient condition for finite-time singularity and tendency towards self-similarity in a high-symmetry flow

NASA Astrophysics Data System (ADS)

Ng, C. S.; Bhattacharjee, A.

A highly symmetric Euler flow, first proposed by Kida (1985), and recently simulated by Boratav and Pelz (1994) is considered. It is found that the fourth order spatial derivative of the pressure (pxxxx) at the origin is most probably positive. It is demonstrated that if pxxxx grows fast enough, there must be a finite-time singularity (FTS). For a random energy spectrum E(k) ∞ k-v, a FTS can occur if the spectral index v<3. Furthermore, a positive pxxxx has the dynamical consequence of reducing the third derivative of the velocity uxxx at the origin. Since the expectation value of uxxx is zero for a random distribution of energy, an ever decreasing uxxx means that the Kida flow has an intrinsic tendency to deviate from a random state. By assuming that uxxx reaches the minimum value for a given spectral profile, the velocity and pressure are found to have locally self-similar forms similar in shape to what are found in numerical simulations. Such a quasi self-similar solution relaxes the requirement for FTS to v<6. A special self-similar solution that satisfies Kelvin's circulation theorem and exhibits a FTS is found for v=2.

VizieR Online Data Catalog: CO, [CI] and [NII] lines from Herschel spectra (Kamenetzky+, 2016)

NASA Astrophysics Data System (ADS)

Kamenetzky, J.; Rangwala, N.; Glenn, J.; Maloney, P. R.; Conley, A.

2016-11-01

We compiled a list of successful extragalactic Herschel/SPIRE FTS proposals (301 spectra) and searched the Herschel Science Archive (HSA) for the available data. Table 1 lists the basic galaxy information and observation IDs for all galaxies for which at least one FTS line measurement or upper limit is reported. The bandpass of the Herschel FTS starts around the CO J=4-3 line, but the majority of the molecular mass in galaxies is cool and populates the lower rotational levels. We complement the line fluxes derived from the FTS with the CO J=1-0, J=2-1, and J=3-2 lines available from ground-based observatories. Many of these galaxies have already been studied in the literature, particularly in large CO surveys. For some galaxies, we also performed single-dish measurements using the Arizona Radio Observatory (ARO). Measurements of the CO J=1-0 line were conducted with the 12m dish on Kitt Peak in 2015 May, and those of CO J=2-1 and J=3-2 were conducted with the Submillimeter Telescope (SMT) located on Mt. Graham from 2014 November to 2015 February. (4 data files).

CIRS-lite, a Fourier Transform Spectrometer for Low-Cost Planetary Missions

NASA Technical Reports Server (NTRS)

Brasunas, J.; Bly, V.; Edgerton, M.; Gong, Q.; Hagopian, J.; Mamakos, W.; Morelli, A.; Pasquale, B.; Strojny, C.

2011-01-01

Passive spectroscopic remote sensing of planetary atmospheres and surfaces in the thermal infrared is a powerful tool for obtaining information about surface and atmospheric temperatures, composition, and dynamics (via the thermal wind equation). Due to its broad spectral coverage, the Fourier transform spectrometer (FTS) is particularly suited to the exploration and discovery of molecular species. NASA's Goddard Space Flight Center (GSFC) developed the CIRS (Composite Infrared Spectrometer) FTS for the NASA/ESA Cassini mission to the Saturnian system. CIRS observes Saturn, Titan, icy moons such as Enceladus, and the rings in thermal self-emission over the spectral range of 7 to 1000 ell11. CIRS has given us important new insights into stratospheric composition and jets on Jupiter and Saturn, the cryo-geyser and thermal stripes on Enceladus, and the winter polar vortex on Titan. CIRS has a mass of 43 kg, contrasted with the earlier GSFC FTS, pre-Voyager IRIS (14 kg). Future low-cost planetary missions will have very tight constraints on science payload mass, thus we must endeavor to return to IRIS-level mass while maintaining CIRS-level science capabilities ("do more with less"). CIRS-lite achieves this by pursuing: a) more sensitive infrared detectors (high Tc superconductor) to enable smaller optics. b) changed long wavelength limit from 1000 to 300 microns to reduce diffraction by smaller optics. c) CVD (chemical vapor deposition) diamond beam-splitter for broad spectral coverage. d) single FTS architecture instead of a dual FTS architecture. e) novel materials, such as single crystal silicon for the input telescope primary.

The price of performance: a cost and performance analysis of the implementation of cell-free fetal DNA testing for Down syndrome in Ontario, Canada.

PubMed

Okun, N; Teitelbaum, M; Huang, T; Dewa, C S; Hoch, J S

2014-04-01

To examine the cost and performance implications of introducing cell-free fetal DNA (cffDNA) testing within modeled scenarios in a publicly funded Canadian provincial Down syndrome (DS) prenatal screening program. Two clinical algorithms were created: the first to represent the current screening program and the second to represent one that incorporates cffDNA testing. From these algorithms, eight distinct scenarios were modeled to examine: (1) the current program (no cffDNA), (2) the current program with first trimester screening (FTS) as the nuchal translucency-based primary screen (no cffDNA), (3) a program substituting current screening with primary cffDNA, (4) contingent cffDNA with current FTS performance, (5) contingent cffDNA at a fixed price to result in overall cost neutrality,(6) contingent cffDNA with an improved detection rate (DR) of FTS, (7) contingent cffDNA with higher uptake of FTS, and (8) contingent cffDNA with optimized FTS (higher uptake and improved DR). This modeling study demonstrates that introducing contingent cffDNA testing improves performance by increasing the number of cases of DS detected prenatally, and reducing the number of amniocenteses performed and concomitant iatrogenic pregnancy loss of pregnancies not affected by DS. Costs are modestly increased, although the cost per case of DS detected is decreased with contingent cffDNA testing. Contingent models of cffDNA testing can improve overall screening performance while maintaining the provision of an 11- to 13-week scan. Costs are modestly increased, but cost per prenatally detected case of DS is decreased. © 2013 John Wiley & Sons, Ltd.

Influence of enhanced recovery after surgery programs on laparoscopy-assisted gastrectomy for gastric cancer: a systematic review and meta-analysis of randomized control trials.

PubMed

Li, Zhengyan; Wang, Qian; Li, Bofei; Bai, Bin; Zhao, Qingchuan

2017-11-23

This meta-analysis is aimed to evaluate the feasibility and safety of enhanced recovery after surgery (ERAS) programs in gastric cancer patients undergoing laparoscopy-assisted gastrectomy (LAG). We performed a meta-analysis of randomized control trials involving either enhanced recovery after surgery (ERAS)/fast track surgery (FTS) for patients underwent LAG. EMBASE, Pubmed, Web of science, and Cochrane Library were searched. Primary outcomes included the length of postoperative hospital stay, cost of hospitalization, postoperative complications, and readmission rate. Five randomized control trials were eligible for analysis. There were 159 cases in FTS group and 156 cases in conventional care group. Compared with conventional care group, FTS group relates to shorter postoperative hospital stay (WMD - 2.16; 95% CI - 3.05 to - 1.26, P < 0.00001), less cost of hospitalization (WMD - 4.72; 95% CI - 6.88 to - 2.55, P < 0.00001), shorter time to first flatus (WMD - 9.72; 95% CI - 13.75 to - 5.81, P < 0.00001), lower level of C-reaction protein on postoperative days 3 or 4 (WMD - 19.66; 95% CI - 28.98 to - 10.34, P < 0.00001), higher level of albumin on postoperative day 4 (WMD 3.45; 95% CI 2.01 to 4.89, P < 0.00001), and postoperative day 7 (WMD 5.63; 95% CI 1.01 to 10.24, P = 0.02). Regarding postoperative complications, no significant differences were observed between FTS group and conventional care group (OR 0.63, 95% CI 0.37 to 1.09, P = 0.10). The readmission rate of FTS group was comparable to conventional care group (WMD 3.14; 95% CI 0.12 to 81.35, P = 0.49). Among patients undergoing LAG, FTS is associated with shorter postoperative hospital stay, rapid postoperative recovery, and decreased cost without increasing complications or readmission rate. The combined effects of the two methods could further accelerate clinical recovery of gastric cancer patients.

Shallow geologic structure of Lake Lacawac, Wayne Co. PA

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

Rohrer, J.W.; Meltzer, A.

1993-03-01

In this study the authors used seismic refraction techniques to characterize the shallow geologic structure around Lake Lacawac in northeastern Pennsylvania. They acquired six high resolution seismic refraction profiles, two each, on the east, west, and north sides of the lake. The lines were oriented perpendicular to each other to constrain dip of interfaces. The authors spaced receivers at 15 ft intervals with a maximum offset of 720 ft. A 12 lb. sledge hammer impacting a steel plate served as a seismic source on the east and west sides of the lake. The north side of the lake is amore » swamp. In the swamp they used a Betsy Seis-gun with 12 gauge shotgun shells as a seismic source, and marsh geophones as receivers. Source locations were 90 feet apart yielding 9 shot gathers per profile. Data was downloaded to a workstation for processing. Each shot record was scaled and bandpass filtered. First arrivals were defined and velocity-depth structure determined. The eastern side of the lake has a 15 ft layer of low velocity, (3,000 ft/s) material underlain by a layer of higher velocity, 7,500 ft/s material. The authors interpret this as a layer of shale below till. On the western side, a 15 ft layer of slow velocity, (3,500 ft/s) material is underlain by high velocity, 12,500 ft/s material. They interpret this as a layer of sandstone beneath till. On the north side of the lake, the surface layer is saturated organic material with an average velocity of 2,550 ft/s. This layer varies in thickness from 0--20 ft. The organic material is underlain by higher velocity material ([approximately]15,000 ft/s) interpreted as sandstone. To the southwest, the sandstone unit disappears across an abrupt, nearly vertical boundary. Minimum vertical offset across this NE/SW striking feature is 114 ft. Forward modeling is being done to help constrain subsurface structure.« less

A Panchromatic Imaging Fourier Transform Spectrometer for the NASA Geostationary Coastal and Air Pollution Events Mission

NASA Technical Reports Server (NTRS)

Wu, Yen-Hung; Key, Richard; Sander, Stanley; Blavier, Jean-Francois; Rider, David

2011-01-01

This paper summarizes the design and development of the Panchromatic Imaging Fourier Transform Spectrometer (PanFTS) for the NASA Geostationary Coastal and Air Pollution Events (GEO-CAPE) Mission. The PanFTS instrument will advance the understanding of the global climate and atmospheric chemistry by measuring spectrally resolved outgoing thermal and reflected solar radiation. With continuous spectral coverage from the near-ultraviolet through the thermal infrared, this instrument is designed to measure pollutants, greenhouse gases, and aerosols as called for by the U.S. National Research Council Decadal Survey; Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond1. The PanFTS instrument is a hybrid instrument based on spectrometers like the Tropospheric Emissions Spectrometer (TES) that measures thermal emission, and those like the Orbiting Carbon Observatory (OCO), and the Ozone Monitoring Instrument (OMI) that measure scattered solar radiation. Simultaneous measurements over the broad spectral range from IR to UV is accomplished by a two sided interferometer with separate optical trains and detectors for the ultraviolet-visible and infrared spectral domains. This allows each side of the instrument to be independently optimized for its respective spectral domain. The overall interferometer design is compact because the two sides share a single high precision cryogenic optical path difference mechanism (OPDM) and metrology laser as well as a number of other instrument systems including the line-of-sight pointing mirror, the data management system, thermal control system, electrical system, and the mechanical structure. The PanFTS breadboard instrument has been tested in the laboratory and demonstrated the basic functionality for simultaneous measurements in the visible and infrared. It is set to begin operations in the field at the California Laboratory for Atmospheric Remote Sensing (CLARS) observatory on Mt. Wilson

Distinct human α(1,3)-fucosyltransferases drive Lewis-X/sialyl Lewis-X assembly in human cells.

PubMed

Mondal, Nandini; Dykstra, Brad; Lee, Jungmin; Ashline, David J; Reinhold, Vernon N; Rossi, Derrick J; Sackstein, Robert

2018-05-11

In humans, six α(1,3)-fucosyltransferases (α(1,3)-FTs: FT3/FT4/FT5/FT6/FT7/FT9) reportedly fucosylate terminal lactosaminyl glycans yielding Lewis-X (Le X ; CD15) and/or sialyl Lewis-X (sLe X ; CD15s), structures that play key functions in cell migration, development, and immunity. Prior studies analyzing α(1,3)-FT specificities utilized either purified and/or recombinant enzymes to modify synthetic substrates under nonphysiological reaction conditions or molecular biology approaches wherein α(1,3)-FTs were expressed in mammalian cell lines, notably excluding investigations using primary human cells. Accordingly, although significant insights into α(1,3)-FT catalytic properties have been obtained, uncertainty persists regarding their human Le X /sLe X biosynthetic range across various glycoconjugates. Here, we undertook a comprehensive evaluation of the lactosaminyl product specificities of intracellularly expressed α(1,3)-FTs using a clinically relevant primary human cell type, mesenchymal stem cells. Cells were transfected with modified mRNA encoding each human α(1,3)-FT, and the resultant α(1,3)-fucosylated lactosaminyl glycoconjugates were analyzed using a combination of flow cytometry and MS. The data show that biosynthesis of sLe X is driven by FTs-3, -5, -6, and -7, with FT6 and FT7 having highest potency. FT4 and FT9 dominantly biosynthesize Le X , and, among all FTs, FT6 holds a unique capacity in creating sLe X and Le X determinants across protein and lipid glycoconjugates. Surprisingly, FT4 does not generate sLe X on glycolipids, and neither FT4, FT6, nor FT9 synthesizes the internally fucosylated sialyllactosamine VIM-2 (CD65s). These results unveil the relevant human lactosaminyl glycans created by human α(1,3)-FTs, providing novel insights on how these isoenzymes stereoselectively shape biosynthesis of vital glycoconjugates, thereby biochemically programming human cell migration and tuning human immunologic and developmental processes. �

Microbial degradation of poly(amino acid)s.

PubMed

Obst, Martin; Steinbüchel, Alexander

2004-01-01

Natural poly(amino acid)s are a group of poly(ionic) molecules (ionomers) with various biological functions and putative technical applications and play, therefore, an important role both in nature and in human life. Because of their biocompatibility and their synthesis from renewable resources, poly(amino acid)s may be employed for many different purposes covering a broad spectrum of medical, pharmaceutical, and personal care applications as well as the domains of agriculture and of environmental applications. Biodegradability is one important advantage of naturally occurring poly(amino acid)s over many synthetic polymers. The intention of this review is to give an overview about the enzyme systems catalyzing the initial steps in poly(amino acid) degradation. The focus is on the naturally occurring poly(amino acid)s cyanophycin, poly(epsilon-L-lysine) and poly(gamma-glutamic acid); but biodegradation of structurally related synthetic polyamides such as poly(aspartic acid) and nylons, which are known from various technical applications, is also included.

An Archive of Spectra from the Mayall Fourier Transform Spectrometer at Kitt Peak

NASA Astrophysics Data System (ADS)

Pilachowski, C. A.; Hinkle, K. H.; Young, M. D.; Dennis, H. B.; Gopu, A.; Henschel, R.; Hayashi, S.

2017-02-01

We describe the SpArc science gateway for spectral data obtained using the Fourier Transform Spectrometer (FTS) in operation at the Mayall 4-m telescope at the Kitt Peak National Observatory during the period from 1975 through 1995. SpArc is hosted by Indiana University Bloomington and is available for public access. The archive includes nearly 10,000 individual spectra of more than 800 different astronomical sources including stars, nebulae, galaxies, and solar system objects. We briefly describe the FTS instrument itself and summarize the conversion of the original interferograms into spectral data and the process for recovering the data into FITS files. The architecture of the archive is discussed and the process for retrieving data from the archive is introduced. Sample use cases showing typical FTS spectra are presented.

Integration of the Reconfigurable Self-Healing eDNA Architecture in an Embedded System

NASA Technical Reports Server (NTRS)

Boesen, Michael Reibel; Keymeulen, Didier; Madsen, Jan; Lu, Thomas; Chao, Tien-Hsin

2011-01-01

In this work we describe the first real world case study for the self-healing eDNA (electronic DNA) architecture by implementing the control and data processing of a Fourier Transform Spectrometer (FTS) on an eDNA prototype. For this purpose the eDNA prototype has been ported from a Xilinx Virtex 5 FPGA to an embedded system consisting of a PowerPC and a Xilinx Virtex 5 FPGA. The FTS instrument features a novel liquid crystal waveguide, which consequently eliminates all moving parts from the instrument. The addition of the eDNA architecture to do the control and data processing has resulted in a highly fault-tolerant FTS instrument. The case study has shown that the early stage prototype of the autonomous self-healing eDNA architecture is expensive in terms of execution time.

The Acid-Base Titration of a Very Weak Acid: Boric Acid

ERIC Educational Resources Information Center

Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

2012-01-01

A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

Omega-3 fatty acids: new insights into the pharmacology and biology of docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid.

PubMed

Davidson, Michael H

2013-12-01

Fish oil contains a complex mixture of omega-3 fatty acids, which are predominantly eicosapentaenoic acid (EPA), docosapentaenoic acid, and docosahexaenoic acid (DHA). Each of these omega-3 fatty acids has distinct biological effects that may have variable clinical effects. In addition, plasma levels of omega-3 fatty acids are affected not only by dietary intake, but also by the polymorphisms of coding genes fatty acid desaturase 1-3 for the desaturase enzymes that convert short-chain polyunsaturated fatty acids to long-chain polyunsaturated fatty acids. The clinical significance of this new understanding regarding the complexity of omega-3 fatty acid biology is the purpose of this review. FADS polymorphisms that result in either lower levels of long-chain omega-3 fatty acids or higher levels of long-chain omega-6 polyunsaturated fatty acids, such as arachidonic acid, are associated with dyslipidemia and other cardiovascular risk factors. EPA and DHA have differences in their effects on lipoprotein metabolism, in which EPA, with a more potent peroxisome proliferator-activated receptor-alpha effect, decreases hepatic lipogenesis, whereas DHA not only enhances VLDL lipolysis, resulting in greater conversion to LDL, but also increases HDL cholesterol and larger, more buoyant LDL particles. Overall, these results emphasize that blood concentrations of individual long-chain polyunsaturated fatty acids, which reflect both dietary intake and metabolic influences, may have independent, but also complementary- biological effects and reinforce the need to potentially provide a complex mixture of omega-3 fatty acids to maximize cardiovascular risk reduction.

Estimating the energy contribution during single and repeated sprint swimming.

PubMed

Peyrebrune, M C; Toubekis, A G; Lakomy, H K A; Nevill, M E

2014-04-01

The extent to which aerobic processes contribute to energy supply during short duration sprint swimming is not known. Therefore, the energy contribution to a maximal 30 s fully tethered swim (FTS), and repeated 4 × 30 s high intensity semi-tethered swimming bouts (STS) with 30 s of passive rest at 95% of the 30 s FTS intensity was estimated in eight elite male swimmers. Blood lactate concentration and pH after the 4 × 30 s test were 12.1 ± 3.6 mmol/L and 7.2 ± 0.1, respectively. Accumulated oxygen demand was estimated to be 50.9 ± 9.6 mL/kg and 48.3 ± 8.4, 47.2 ± 8.5, 47.4 ± 8.3, and 45.6 ± 6.8 mL/kg for the 30 s FTS and 4 × 30 s bouts, respectively. Accumulated oxygen uptake was 16.6 ± 3.6 for the 30 s FTS and progressively increased during the 4 × 30 s bouts 12.2 ± 2.1, 21.6 ± 2.5, 22.8 ± 1.8, and 23.5 ± 2.0 mL/kg (P < 0.01). The estimated aerobic contribution therefore was 33 ± 8% for the 30 s FTS and 25 ± 4, 47 ± 9, 49 ± 8, 52 ± 9% for bouts 1-4 during the 4 × 30 s STS test (P < 0.01). The results underline the importance of aerobic energy contribution during single and repeated high intensity swimming, which should be considered when prescribing swimming training sets of this nature. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effect of Fodder Tree Species with Condensed Tannin Contents on In vitro Methane Production

PubMed Central

Vázquez, Ernestina Gutiérrez; Medina, Leonardo Hernández; Benavides, Liliana Márquez; Caratachea, Aureliano Juárez; Razo, Guillermo Salas; Burgos, Armin Javier Ayala; Rodríguez, Ruy Ortiz

2016-01-01

The objective was to evaluate the effect of fodder tree species (FTS) with condensed tannin contents: Cordia elaeagnoides, Platymiscium lasiocarpum, Vitex mollis, and Haematoxylon brasiletto, on in vitro methane (CH4) production at 24 h post incubation. The analysis was performed using the in vitro gas production technique, with three levels of inclusion/species: 600, 800, and 1,000 mg and with 4 replicates/species/level of inclusion. The substrate was incubated at 39°C, and the gas and CH4 production were recorded at 4, 8, 12, and 24 h post incubation. The data collected was analyzed through Pearson correlation, polinomial regression and fixed effects models. There were negative correlations between FTS-total gas volume (r = −0.40; p<0.001); FTS-volume of CH4 produced (r = −0.40; p<0.001) and between the inclusion level-volume of CH4 produced (r = −0.20; p<0.001). As well as a positive correlation between hours post incubation-total gas volume (r = 0.42; p<0.001) and between hours post incubation-volume of CH4 produced (r = 0.48; p<0.001). The FTS: C. elaeagnoides, V. mollis, and H. brasiletto have potential, in the three inclusion levels analyzed, to reduce CH4 emission on in vitro trials (>32.7%), taking into account the total CH4 production at 24 h of the forage used as reference (Avena sativa). It’s suggested that C. elaeagnoides-according to its crude protein, neutral detergent fiber, and condensed tannins content- is the best alternative within the FTS analyzed, for feeding ruminants and for the control of CH4 emissions during the dry season. PMID:26732330

Fast-track bariatric surgery improves perioperative care and logistics compared to conventional care.

PubMed

Dogan, Kemal; Kraaij, Linda; Aarts, Edo O; Koehestanie, Parweez; Hammink, Edwin; van Laarhoven, Cees J H M; Aufenacker, Theo J; Janssen, Ignace M C; Berends, Frits J

2015-01-01

Due to the increased incidence of morbid obesity, the demand for bariatric surgery is increasing. Therefore, the methods for optimising perioperative care for the improvement of surgical outcome and to increase efficacy are necessary. The aim of this prospective matched cohort study is to objectify the effect of the fast-track surgery (FTS) programme in patients undergoing primary Laparoscopic Roux-en-Y Gastric Bypass (LRYGB) surgery compared to conventional perioperative care (CPC). This study compared the perioperative outcome data of two groups of 75 consecutive morbid obese patients who underwent a primary LRYGB according to international guidelines in the periods January 2011-April 2011 (CPC group) and April 2012-June 2012 (FTS group). The two groups were matched for age and sex. Primary endpoints were surgery and hospitalisation time, while secondary endpoints were intraoperative medication use and complication rates. Baseline patient characteristics for age, sex, weight and ASA classification were similar (p > 0.05) for CPC and FTS patients. BMI and waist circumference were significantly lower (p < 0.05) in the FTS compared to CPC. The total time from arrival at the operating room to the arrival at the recovery was reduced from 119 to 82 min (p < 0.001). Surgery time was reduced from 80 to 56 min (p < 0.001); mean hospital stay was reduced from 65 to 43 h (p < 0.001). Major complications occurred in 3 versus 4 % in the FTS and CPC, respectively. The introduction of a fast-track programme after primary LRYGB improves short-term recovery and may reduces direct hospital-related resources.

In-flight demonstration of the Space Station Freedom Health Maintenance Facility fluid therapy system (E300/E05)

NASA Technical Reports Server (NTRS)

Lloyd, Charles W.

1993-01-01

The Space Station Freedom (SSF) Health Maintenance Facility (HMF) will provide medical care for crew members for up to 10 days. An integral part of the required medical care consists of providing intravenous infusion of fluids, electrolyte solutions, and nutrients to sustain an ill or injured crew member. In terrestrial health care facilities, intravenous solutions are normally stored in large quantities. However, due to the station's weight and volume constraints, an adequate supply of the required solutions cannot be carried onboard SSF. By formulating medical fluids onboard from concentrates and station water as needed, the Fluid Therapy System (FTS) eliminates weight and volume concerns regarding intravenous fluids. The first full-system demonstration of FTS is continuous microgravity will be conducted in Spacelab-Japan (SL-J). The FTS evaluation consists of two functional objectives and an in-flight demonstration of intravenous administration of fluids. The first is to make and store sterile water and IV solutions onboard the spacecraft. If intravenous fluids are to be produced in SSF, successful sterilization of water and reconstituting of IV solutions must be achieved. The second objective is to repeat the verification of the FTS infusion pump, which had been performed in Spacelab Life Sciences - 1 (SLS-1). during SLS-1, the FTS IV pump was operated in continuous microgravity for the first time. The pump functioned successfully, and valuable knowledge on its performance in continuous microgravity was obtained. Finally, the technique of starting an IF in microgravity will be demonstrated. The IV technique requires modifications in microgravity, such as use of restraints for equipment and crew members involved.

Noninvasive prenatal testing in routine clinical practice--an audit of NIPT and combined first-trimester screening in an unselected Australian population.

PubMed

McLennan, Andrew; Palma-Dias, Ricardo; da Silva Costa, Fabricio; Meagher, Simon; Nisbet, Debbie L; Scott, Fergus

2016-02-01

There are limited data regarding noninvasive prenatal testing (NIPT) in low-risk populations, and the ideal aneuploidy screening model for a pregnant population has yet to be established. To assess the implementation of NIPT into clinical practice utilising both first- and second-line screening models. Three private practices specialising in obstetric ultrasound and prenatal diagnosis in Australia offered NIPT as a first-line test, ideally followed by combined first-trimester screening (cFTS), or as a second-line test following cFTS, particularly in those with a calculated risk between 1:50 and 1:1000. NIPT screening was performed in 5267 women and as a first-line screening method in 3359 (63.8%). Trisomies 21 and 13 detection was 100% and 88% for trisomy 18. Of cases with known karyotypes, the positive predictive value (PPV) of the test was highest for trisomy 21 (97.7%) and lowest for monosomy X (25%). Ultrasound detection of fetal structural abnormality resulted in the detection of five additional chromosome abnormalities, two of which had high-risk cFTS results. For all chromosomal abnormalities, NIPT alone detected 93.4%, a contingent model detected 81.8% (P = 0.097), and cFTS alone detected 65.9% (P < 0.005). NIPT achieved 100% T21 detection and had a higher DR of all aneuploidy when used as a first-line test. Given the false-positive rate for all aneuploidies, NIPT is an advanced screening test, rather than a diagnostic test. The benefit of additional cFTS was the detection of fetal structural abnormalities and some unusual chromosomal abnormalities. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Screening options for Down syndrome: how women choose in real clinical setting.

PubMed

Lo, T K; Lai, F K; Leung, W C; Lau, W L; Ng, L S; Wong, W C; Tam, S S; Yee, Y C; Choi, H; Lam, H S W; Sham, A S Y; Tang, L C H; Chin, R K H

2009-09-01

To study pregnant women's preference among various screening options for Down syndrome (DS) in routine clinical setting, and its potential association with women's demographic characteristics. Women aged 35 years and older carrying singleton pregnancy were offered a variety of screening tests for DS before 14 weeks of gestation. Their preference was confirmed by the test they actually underwent. The association between women's choice of test and a number of demographic characteristics was studied using multinomial regression. Among 1967 eligible women, 619 opted for first-trimester screening test (FTS), 924 for partial integrated test (PIT), and 424 for full integrated test (FIT). Nulliparous women and working mothers were more likely to choose FTS and FIT. Women with history of subfertility were more likely to choose FIT. Women with family history of chromosomal abnormalities were more likely to choose FTS. The choice of screening test could be predicted for 49.9% of women using four demographic characteristics. Among older women of predominantly Chinese ethnicity, integrated test is a favorite alternative to FTS. Their choice of DS screening test can be predicted by their obstetric and socioeconomic characteristics. Many women show willingness to pay for a test with a lower false-positive rate.

Boric acid and boronic acids inhibition of pigeonpea urease.

PubMed

Reddy, K Ravi Charan; Kayastha, Arvind M

2006-08-01

Urease from the seeds of pigeonpea was competitively inhibited by boric acid, butylboronic acid, phenylboronic acid, and 4-bromophenylboronic acid; 4-bromophenylboronic acid being the strongest inhibitor, followed by boric acid > butylboronic acid > phenylboronic acid, respectively. Urease inhibition by boric acid is maximal at acidic pH (5.0) and minimal at alkaline pH (10.0), i.e., the trigonal planar B(OH)3 form is a more effective inhibitor than the tetrahedral B(OH)4 -anionic form. Similarly, the anionic form of phenylboronic acid was least inhibiting in nature.

Intra-articular Fibroma of Tendon Sheath in Knee Joint Associated with Iliotibial Band Friction Syndrome: Rare Occurrence in a Teenage Girl

PubMed Central

Rathore, Sameer; Quadri, Vasil; Tapadia, Sanjay; Krishnaiah, K; Krishna, V P Nithin

2017-01-01

Introduction: Iliotibial band (ITB) friction syndrome is a common overuse injury typically seen in active athlete population. A nodular lesion on the inner side of the ITB as an etiology or an accompanying lesion with friction syndrome has rarely been reported. Among such nodular lesions around knee, fibroma of tendon sheath (FTS) is a rare occurrence. All the more intra-articular occurrence is extremely rare. Case Report: A 16-year-old female presented with recurrent pain and movable nodule at the lateral joint area, diagnosed as ITB friction syndrome. The nodule was confirmed as rare intra-articular FTS on the basis of histopathology findings. Conclusion: When nodular lesions around knee are detected on magnetic resonance imaging, a FTS could be included in the differential diagnosis. Etiology and pathogenesis of ITB friction syndrome should be revised in view of such rare presentations. PMID:28630835

A Functional Description of a Digital Flight Test System for Navigation and Guidance Research in the Terminal Area

NASA Technical Reports Server (NTRS)

Hegarty, D. M.

1974-01-01

A guidance, navigation, and control system, the Simulated Shuttle Flight Test System (SS-FTS), when interfaced with existing aircraft systems, provides a research facility for studying concepts for landing the space shuttle orbiter and conventional jet aircraft. The SS-FTS, which includes a general-purpose computer, performs all computations for precisely following a prescribed approach trajectory while properly managing the vehicle energy to allow safe arrival at the runway and landing within prescribed dispersions. The system contains hardware and software provisions for navigation with several combinations of possible navigation aids that have been suggested for the shuttle. The SS-FTS can be reconfigured to study different guidance and navigation concepts by changing only the computer software, and adapted to receive different radio navigation information through minimum hardware changes. All control laws, logic, and mode interlocks reside solely in the computer software.

Peptidoglycan Synthesis Machinery in Agrobacterium tumefaciens During Unipolar Growth and Cell Division

PubMed Central

Cameron, Todd A.; Anderson-Furgeson, James; Zupan, John R.; Zik, Justin J.

2014-01-01

ABSTRACT The synthesis of peptidoglycan (PG) in bacteria is a crucial process controlling cell shape and vitality. In contrast to bacteria such as Escherichia coli that grow by dispersed lateral insertion of PG, little is known of the processes that direct polar PG synthesis in other bacteria such as the Rhizobiales. To better understand polar growth in the Rhizobiales Agrobacterium tumefaciens, we first surveyed its genome to identify homologs of (~70) well-known PG synthesis components. Since most of the canonical cell elongation components are absent from A. tumefaciens, we made fluorescent protein fusions to other putative PG synthesis components to assay their subcellular localization patterns. The cell division scaffolds FtsZ and FtsA, PBP1a, and a Rhizobiales- and Rhodobacterales-specific l,d-transpeptidase (LDT) all associate with the elongating cell pole. All four proteins also localize to the septum during cell division. Examination of the dimensions of growing cells revealed that new cell compartments gradually increase in width as they grow in length. This increase in cell width is coincident with an expanded region of LDT-mediated PG synthesis activity, as measured directly through incorporation of exogenous d-amino acids. Thus, unipolar growth in the Rhizobiales is surprisingly dynamic and represents a significant departure from the canonical growth mechanism of E. coli and other well-studied bacilli. PMID:24865559

Acid Rain

USGS Publications Warehouse

Bricker, Owen P.; Rice, Karen C.

1995-01-01

Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

Effects of Loading and Doping on Iron-Based CO2 Hydrogenation Catalysts

DTIC Science & Technology

2009-08-24

dopant had on the overall catalyst’s activity and production distribution. 24-08-2009 Memorandum Report Naval Research Laboratory, Code 6183 4555...approach in producing a greater yield of hydrocarbon (HC) products above methane. The use of traditional Fischer-Tropsch synthesis (FTS) cobalt ...previous work done by our group [14] it is apparent that direct hydrogenation of CO2 over a general Cobalt -based FTS catalyst (namely Co-Pt/Al2O3

Understanding the Influence of Turbulence in Imaging Fourier-Transform Spectrometry of Smokestack Plumes

DTIC Science & Technology

2011-03-01

capability of FTS to estimate plume effluent concentrations by comparing intrusive measurements of aircraft engine exhaust with those from an FTS. A... turbojet engine. Temporal averaging was used to reduce SCAs in the spectra, and spatial maps of temperature and concentration were generated. The time...density function ( PDF ) is the de- fined as the derivative of the CDF, and describes the probability of obtaining a given value of X. For a normally

Role of ZrO 2 in Promoting the Activity and Selectivity of Co-Based Fischer–Tropsch Synthesis Catalysts

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

Johnson, Gregory R.; Bell, Alexis T.

2015-11-17

The effects of Zr promotion on the structure and performance of Co-based Fischer-Tropsch synthesis (FTS) catalysts were investigated. Inclusion of Zr in the catalysts was found to increase the FTS turnover frequency and the selectivity to C 5+ hydrocarbons and to decrease the selectivity to methane under most operating conditions. These improvements to the catalytic performance are a function of Zr loading up to an atomic ratio of Zr/Co = 1.0, above which the product selectivity is insensitive to higher concentrations of the promoter. Characterization of the Co nanoparticles by different methods demonstrated that the optimal Zr loading corresponds tomore » half monolayer coverage of the Co surface by the promoter. Measurements of the rate of FTS at different pressures and temperatures established that the kinetics data for both the Zr-promoted and unpromoted catalysts are described by a two-parameter Langmuir-Hinshelwood expression. The parameters used to fit this rate law to the experimental data indicate that the apparent rate coefficient and the CO adsorption constant for the Zr-promoted catalysts are higher than those for the unpromoted catalyst. Elemental mapping by means of STEM-EDS provided evidence that Zr is highly dispersed over the catalyst surface and has limited preference for association with the Co nanoparticles. In situ X-ray absorption spectroscopy confirmed the absence of mixing between the Zr and Co in the nanoparticles. Here, these results suggest that Zr exists as a partial layer of ZrO 2 on the surface of the Co metal nanoparticles. Accordingly, it is proposed that Zr promotion effects originate from sites of enhanced activity at the interface between Co and ZrO 2. The possibility that ZrO 2 acts as a Lewis acid to assist in CO dissociation as well as to increase the ratio of CO to H adsorbed on the catalyst surface is discussed.« less

Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

PubMed

Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

2002-12-06

Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

Enantioselective oxidation of racemic lactic acid to D-lactic acid and pyruvic acid by Pseudomonas stutzeri SDM.

PubMed

Gao, Chao; Qiu, Jianhua; Li, Jingchen; Ma, Cuiqing; Tang, Hongzhi; Xu, Ping

2009-03-01

D-lactic acid and pyruvic acid are two important building block intermediates. Production of D-lactic acid and pyruvic acid from racemic lactic acid by biotransformation is economically interesting. Biocatalyst prepared from 9 g dry cell wt l(-1) of Pseudomonas stutzeri SDM could catalyze 45.00 g l(-1)DL-lactic acid into 25.23 g l(-1)D-lactic acid and 19.70 g l(-1) pyruvic acid in 10h. Using a simple ion exchange process, D-lactic acid and pyruvic acid were effectively separated from the biotransformation system. Co-production of d-lactic acid and pyruvic acid by enantioselective oxidation of racemic lactic acid is technically feasible.

Effect of propionic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

PubMed

Xu, Jian; Bao, Jia-Wei; Su, Xian-Feng; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2016-03-01

In this study, an integrated citric acid-methane fermentation process was established to solve the problem of wastewater treatment in citric acid production. Citric acid wastewater was treated through anaerobic digestion and then the anaerobic digestion effluent (ADE) was further treated and recycled for the next batch citric acid fermentation. This process could eliminate wastewater discharge and reduce water resource consumption. Propionic acid was found in the ADE and its concentration continually increased in recycling. Effect of propionic acid on citric acid fermentation was investigated, and results indicated that influence of propionic acid on citric acid fermentation was contributed to the undissociated form. Citric acid fermentation was inhibited when the concentration of propionic acid was above 2, 4, and 6 mM in initial pH 4.0, 4.5 and, 5.0, respectively. However, low concentration of propionic acid could promote isomaltase activity which converted more isomaltose to available sugar, thereby increasing citric acid production. High concentration of propionic acid could influence the vitality of cell and prolong the lag phase, causing large amount of glucose still remaining in medium at the end of fermentation and decreasing citric acid production.

Imipenem heteroresistance in nontypeable Haemophilus influenzae is linked to a combination of altered PBP3, slow drug influx and direct efflux regulation.

PubMed

Cherkaoui, A; Diene, S M; Renzoni, A; Emonet, S; Renzi, G; François, P; Schrenzel, J

2017-02-01

To investigate the potential roles of PBPs, efflux pumps and slow drug influx for imipenem heteroresistance in nontypeable Haemophilus influenzae (NTHi). Fifty-nine NTHi clinical isolates examined in this study were collected at Geneva University Hospitals between 2009 and 2014. Alterations in PBPs were investigated by gene sequencing. To evaluate the affinities of the PBPs to imipenem, steady-state concentration-response experiments were carried out using imipenem in a competition assay with Bocillin-FL. The effect of the carbonyl cyanide m-chlorophenylhydrazone (CCCP) on imipenem susceptibility was assessed using broth dilution and viable cell counting. Using whole-genome sequencing, we explored the potential roles of outer membrane protein P2 (OmpP2), LytM proteins and the dcw gene cluster in imipenem heteroresistance. All 46 imipenem-heteroresistant isolates (IMI hR ) harboured amino acid substitutions in the ftsI gene, which encodes PBP3, corresponding to 25 different mutation patterns that varied from the ftsI gene mutation patterns found in imipenem-susceptible isolates. Among all PBPs, the highest affinity to imipenem was documented for PBP3 (IC 50 , 0.004 μg/mL). Different amino acid substitutions and insertions were noted in OmpP2, suggesting a relationship with imipenem heteroresistance. The IMI hR isolates were affected by CCCP differently and displayed a higher percentage of killing by imipenem in CCCP-treated cells at concentrations ranging between 0.5 and 8 μg/mL. The present study provides robust evidence indicating that in combination with the altered PBP3, the slowed drug influx and its enhanced efflux due to the loss of regulation led to the development of imipenem heteroresistance in NTHi. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Effect of baseline plasma fatty acids on eicosapentaenoic acid levels in individuals supplemented with alpha-linolenic acid.

PubMed

DeFilippis, Andrew P; Harper, Charles R; Cotsonis, George A; Jacobson, Terry A

2009-01-01

We previously reported a >50% increase in mean plasma eicosapentaenoic acid levels in a general medicine clinic population after supplementation with alpha-linolenic acid. In the current analysis, we evaluate the variability of changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid and evaluated the impact of baseline plasma fatty acids levels on changes in eicosapentaenoic acid levels in these individuals. Changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid ranged from a 55% decrease to a 967% increase. Baseline plasma fatty acids had no statistically significant effect on changes in eicosapentaenoic levels acid after alpha-linolenic acid supplementation. Changes in eicosapentaenoic acid levels varied considerably in a general internal medicine clinic population supplemented with alpha-linolenic acid. Factors that may impact changes in plasma eicosapentaenoic acid levels after alpha-linolenic acid supplementation warrant further study.

Specific bile acids inhibit hepatic fatty acid uptake

PubMed Central

Nie, Biao; Park, Hyo Min; Kazantzis, Melissa; Lin, Min; Henkin, Amy; Ng, Stephanie; Song, Sujin; Chen, Yuli; Tran, Heather; Lai, Robin; Her, Chris; Maher, Jacquelyn J.; Forman, Barry M.; Stahl, Andreas

2012-01-01

Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. Here we tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%. In summary, the data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease. PMID:22531947

The use of graphics in the design of the human-telerobot interface

NASA Technical Reports Server (NTRS)

Stuart, Mark A.; Smith, Randy L.

1989-01-01

The Man-Systems Telerobotics Laboratory (MSTL) of NASA's Johnson Space Center employs computer graphics tools in their design and evaluation of the Flight Telerobotic Servicer (FTS) human/telerobot interface on the Shuttle and on the Space Station. It has been determined by the MSTL that the use of computer graphics can promote more expedient and less costly design endeavors. Several specific examples of computer graphics applied to the FTS user interface by the MSTL are described.

Accelerating the two-point and three-point galaxy correlation functions using Fourier transforms

NASA Astrophysics Data System (ADS)

Slepian, Zachary; Eisenstein, Daniel J.

2016-01-01

Though Fourier transforms (FTs) are a common technique for finding correlation functions, they are not typically used in computations of the anisotropy of the two-point correlation function (2PCF) about the line of sight in wide-angle surveys because the line-of-sight direction is not constant on the Cartesian grid. Here we show how FTs can be used to compute the multipole moments of the anisotropic 2PCF. We also show how FTs can be used to accelerate the 3PCF algorithm of Slepian & Eisenstein. In both cases, these FT methods allow one to avoid the computational cost of pair counting, which scales as the square of the number density of objects in the survey. With the upcoming large data sets of Dark Energy Spectroscopic Instrument, Euclid, and Large Synoptic Survey Telescope, FT techniques will therefore offer an important complement to simple pair or triplet counts.

[The investigation and simulation of a novel spatially modulated micro-Fourier transform spectrometer].

PubMed

Kong, Yan-mei; Liang, Jing-qiu; Wang, Bo; Liang, Zhong-zhu; Xu, Da-wei; Zhang, Jun

2009-04-01

Fourier transform spectrometer (FTS) is widely used in science and industry for the measurement of electromagnetic spectra, and it's trend of minimization is particularly pronounced in many applications. A novel model of a micro FTS with no moving parts is proposed and analyzed. During the analysis, the gradients which mainly introduce the phase error are accounted for in details. Based on these assumptions and the improved Mertz phase correcting method, the spectrum of the signal is simulated, given the real extended light source. The resolution can reach 3.43 nm@800 nm, with high SNR limiting resolving ability 6.8 dB. The novel micro FTS could be made by MOEMS technology, which has some advantages over the conventional micro dispersive spectrometers based on the traditional technology, and this method can also afford some new concepts on the design of spectrometers. The research work is underway to demonstrate the theory.

Multilayer Stock Forecasting Model Using Fuzzy Time Series

PubMed Central

Javedani Sadaei, Hossein; Lee, Muhammad Hisyam

2014-01-01

After reviewing the vast body of literature on using FTS in stock market forecasting, certain deficiencies are distinguished in the hybridization of findings. In addition, the lack of constructive systematic framework, which can be helpful to indicate direction of growth in entire FTS forecasting systems, is outstanding. In this study, we propose a multilayer model for stock market forecasting including five logical significant layers. Every single layer has its detailed concern to assist forecast development by reconciling certain problems exclusively. To verify the model, a set of huge data containing Taiwan Stock Index (TAIEX), National Association of Securities Dealers Automated Quotations (NASDAQ), Dow Jones Industrial Average (DJI), and S&P 500 have been chosen as experimental datasets. The results indicate that the proposed methodology has the potential to be accepted as a framework for model development in stock market forecasts using FTS. PMID:24605058

Fluorescence-based thermal shift data on multidrug regulator AcrR from Salmonella enterica subsp. entrica serovar Typhimurium str. LT2.

PubMed

Manjasetty, Babu A; Halavaty, Andrei S; Luan, Chi-Hao; Osipiuk, Jerzy; Mulligan, Rory; Kwon, Keehwan; Anderson, Wayne F; Joachimiak, Andrzej

2016-06-01

The fluorescence-based thermal shift (FTS) data presented here include Table S1 and Fig. S1, and are supplemental to our original research article describing detailed structural, FTS, and fluorescence polarization analyses of the Salmonella enterica subsp. entrica serovar Typhimurium str. LT2 multidrug transcriptional regulator AcrR (StAcrR) (doi:10.1016/j.jsb.2016.01.008) (Manjasetty et al., 2015 [1]). Table S1 contains chemical formulas, a Chemical Abstracts Service (CAS) Registry Number (CAS no.), FTS rank (a ligand with the highest rank) has the largest difference in the melting temperature (ΔT m), and uses as drug molecules against various pathological conditions of sixteen small-molecule ligands that increase thermal stability of StAcrR. Thermal stability of human enolase 1, a negative control protein, was not affected in the presence of various concentrations of the top six StAcrR binders (Fig. S1).

Right-hemispheric dominance for processing extended non-linguistic frequency transitions.

PubMed

McKibbin, Katherine; Elias, Lorin J; Saucier, Deborah M; Engebregston, Delaine

2003-11-01

The left hemisphere is specialized for most linguistic tasks and the right hemisphere is specialized for many non-linguistic tasks, but the cause of these functional asymmetries is unknown. One of the stimulus factors that appears to influence these asymmetries is the rate at which stimuli change. In the present experiment, 41 participants completed the Fused Dichotic Words Test (FDWT) and a non-linguistic Frequency Transition Task (FTT) wherein the Frequency Transitions (FTs) were either rapid (40 ms) or relatively slow (200 ms). There was a right hemisphere advantage for slow FTs when the change was at the front of the stimulus, but no corresponding left hemisphere advantage for the rapid FTs. There was no relationship between either FTT and the left hemisphere advantage exhibited on the FDWT. This finding provides support for the position that the right hemisphere dominates tasks that require temporal processing over relatively long periods of time.

The WEAVE focus translation system: from design to construction

NASA Astrophysics Data System (ADS)

Canchado, Manuel; Romero, Antonio; Maroto, Óscar; Tomas, Albert; Martín-Nuño, Carlos; Casalta, Joan Manel; Prida, Joaquín.; L. Aguerri, J. Alfonso; Herreros, José Miguel; Delgado, José Miguel; Burgal, José Alonso; Abrams, Don Carlos; Dee, Kevin; Dalton, Gavin; Bonifacio, Piercarlo; Trager, Scott C.; Vallenari, Antonella

2016-07-01

WEAVE is a new wide-field spectroscopy facility proposed for the prime focus of the 4.2m William Herschel Telescope (WHT), placed in La Palma, Canary Islands, Spain. To allow for the compensation of the effects of temperature-induced and gravity-induced image degradation, the WEAVE prime focus assembly will be translated along the telescope optical axis. The assembly comprises the prime focus corrector with integrated ADC, a central mount for the corrector, an instrument rotator and a twin-focal-plane fibre positioner. Translation is accomplished through the use of a set of purpose-built actuators; collectively referred to as the Focus Translation System (FTS), formed by four independently-controlled Focus Translation Units (FTUs), eight vanes connecting the FTUs to a central can, and a central can hosting WEAVE Instrument. Each FTU is capable of providing a maximum stroke of +/-4mm with sufficient, combined force to move the five-tonne assembly with a positional accuracy of +/-20μm at a resolution of 5μm. The coordinated movement of the four FTUs allows +/-3mm WEAVE focus adjustment in the optical axis and +/-0.015° tilt correction in one axis. The control of the FTS is accomplished through a PLC-based subsystem that receives positional demands from the higher-level Instrument Control System. SENER has been responsible for designing, manufacturing and testing the FTS and the equipment required to manipulate and store the FTS together with the instrument. This manuscript describes the final design of the FTS along with the analyses and simulations that were performed, discusses the manufacturing procedures and the results of early verification prior to integration with the telescope. The plans for mounting the whole system on the telescope are also discussed.

Alaskan frozen soil impact tests of the B83-C/S and Strategic Earth Penetrator

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

Dockery, H.A.; Clarke, J.B.; Stull, S.P.

To assess the penetrability of the B83 strategic bomb and a Strategic Earth Penetrator design into frozen soil and ice, Lawrence Livermore National Laboratory and Sandia National Laboratories, assisted by the US Air Force and US Army, conducted a series of tests in 1987. In April, Strategic Earth Penetrator units were dropped into multi-year sea ice and frozen tundra near Prudhoe Bay, Alaska. Calculated impact velocity ranged from 200 to 308 ft/s into ice and from 200 to 444 ft/s into frozen tundra. Tests in May include drops of a B83 design with specially designed ogive nose shape, a B83more » with a cap over the production ''cookie cutter'' nose, and a Strategic Earth Penetrator. The May tests were conducted near Fairbanks, Alaska, at Eielson Air Force Base and at Donnelly Flats on the Fort Greely Military Reservation. The type of frozen soil encountered at Eielson was very homogeneous in composition; however. Two drops impacted areas with very thin frozen soil layers at depths of about 24 in. below the surface. Velocities of these drops prior to impact ranged from 256 to 308 ft/s, and peak axial deceleration ranged from 160 to 490 g. The units penetrated to depths of 7.5-12 ft. Three other events impacted in a target area where frozen soil averaging 35 in. thick extended essentially to the surface. We calculated velocities prior to impact at 200-256 ft/s; and penetration depths of 3.2-9.6 ft. The geologic material at Donnelly Flats was primarily a very hard, rocky glacial deposit with a variable degree of ice bonding. Here, the test units dropped from 10,000 ft above ground level and achieved an average calculated velocity of 802 ft/s. Depth of penetration ranged from 7.6 to 13.5 ft.« less

Retrieval Analysis of the CO2 1.6 μm Band in Solar Absorption Spectra Measured by a Ground-Based High-Resolution Fourier Transform Spectrometer at Tsukuba

NASA Astrophysics Data System (ADS)

Ohyama, H.; Morino, I.; Nagahama, T.; Suto, H.; Oguma, H.; Machida, T.; Sugimoto, N.; Nakane, H.; Nakagawa, K.

2006-12-01

The global measurements of greenhouse gases from space are being planned, such as GOSAT (Greenhouse gases Observing SATellite) and OCO (Orbiting Carbon Observatory). Satellite remote sensing needs validations with other measurement techniques, for example, in-situ or sampling measurement by aircraft or ground station, or remote sensing measurement by ground-based Fourier Transform Spectrometer (FTS). The ground-based FTS measurement can provide the column amounts of atmospheric composition by a retrieval analysis with relatively high precision. In 2001, we started a project to observe the atmospheric compositions in solar absorption spectra by a ground- based high-resolution FTS (Bruker IFS 120 HR) located at Tsukuba, Japan. Three years ago, optical components of the FTS were replaced for measuring greenhouse gases such as carbon dioxide (CO2) and methane (CH4) in the near-infrared region: a CaF2 beam splitter, an InSb detector, and a 1.4-2.4 μm optical filter. The measurements were carried out once a day for ~100 days per year. We also made simultaneous FTS and aircraft in-situ measurements on August 10, 2004 and March 30, 2005. The retrieval analysis was performed for the measured spectra in the CO2 1.6 μm band. We used SEASCRAPE PLUS (Sequential Evaluation Algorithm for Simultaneous and Concurrent Retrieval of Atmospheric Parameter Estimates PLUS, Remote Sensing Analysis Systems, Inc.) as a retrieval analysis program. The column amounts were compared with those derived from in-situ measurements complemented by model data; differences are less than 1%. We have derived the diurnal variations of CO2 on the same days as in-situ measurements, and they showed tendencies similar to the tower measurements at the Meteorological Research Institute in Tsukuba.

Assessing the impact of the SOGC recommendations to increase access to prenatal screening on overall use of health resources in pregnancy.

PubMed

Metcalfe, Amy; Lix, Lisa M; Johnson, Jo-Ann; Bernier, François; Currie, Gillian; Lyon, Andrew W; Tough, Suzanne C

2013-05-01

The recommendation by the Society of Obstetricians and Gynaecologists of Canada that prenatal screening for fetal aneuploidy be offered to all pregnant women is an important change in clinical obstetrics. However, it is unknown how this recommendation might affect the use of other health resources during pregnancy. Twelve clinical and administrative databases were linked, and care paths outlining typical service use in pregnancy were created based on the type of prenatal screening accessed (first trimester screening [FTS], maternal serum screening [MSS], invasive testing only, or no screening and/or diagnosis). Logistic, Poisson, and negative binomial models were applied to the data to examine the association between use of prenatal screening/diagnosis and other health services during pregnancy. Women who accessed prenatal screening/diagnosis were significantly more likely to have a consultation with a medical geneticist (FTS OR 2.42; 95% CI 1.75 to 3.33; MSS OR 4.84; 95% CI 2.92 to 8.03; and invasive testing OR 8.58; 95% CI 5.28 to 13.94), and women who accessed FTS had more prenatal visits (FTS incidence rate ratio 1.03; 95% CI 1.01 to 1.05) than women who did not access prenatal screening/diagnosis. Uptake of invasive tests did not differ between women who accessed FTS and those who accessed MSS. Use of prenatal screening/diagnosis was not significantly associated with use of most other health resources In a publicly funded health care system, understanding the impact of recommendations to increase access to a specific service on other services is important. Recommendations to increase access to prenatal screening services may have some unanticipated downstream effects on the use of other services during pregnancy. However, most aspects of health resource use in pregnancy do not appear to be influenced by the use of prenatal screening services.

[Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

PubMed

Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

2016-03-01

Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.

PubMed

Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

2012-11-01

A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ≈ Erie > Huron > Superior ≈ Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid.

Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

PubMed Central

Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

1988-01-01

A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

Production of succinic Acid from citric Acid and related acids by lactobacillus strains.

PubMed

Kaneuchi, C; Seki, M; Komagata, K

1988-12-01

A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, alpha-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli.

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin.

PubMed

Seto, Jennifer E; Polat, Baris E; Lopez, Renata F V; Blankschtein, Daniel; Langer, Robert

2010-07-01

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700microm-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. 2010 Elsevier B.V. All rights reserved.

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin

PubMed Central

Seto, Jennifer E.; Polat, Baris E.; Lopez, Renata F.V.; Blankschtein, Daniel; Langer, Robert

2010-01-01

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700-μm-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. PMID:20346994

Ratiometric Nanothermometer Based on Rhodamine Dye-Incorporated F127-Melamine-Formaldehyde Polymer Nanoparticle: Preparation, Characterization, Wide-Range Temperature Sensing, and Precise Intracellular Thermometry.

PubMed

Wu, Youshen; Liu, Jiajun; Ma, Jingwen; Liu, Yongchun; Wang, Ya; Wu, Daocheng

2016-06-15

A series of fluorescent nanothermometers (FTs) was prepared with Rhodamine dye-incorporated Pluronic F-127-melamine-formaldehyde composite polymer nanoparticles (R-F127-MF NPs). The highly soluble Rhodamine dye molecules were bound with Pluronic F127 micelles and subsequently incorporated in the cross-linked MF resin NPs during high-temperature cross-link treatment. The morphology and chemical structure of R-F127-MF NPs were characterized with dynamic light scattering, electron microscopy, and Fourier-transform infrared (FTIR) spectra. Fluorescence properties and thermoresponsivities were analyzed using fluorescence spectra. R-F127-MF NPs are found to be monodispersed, presenting a size range of 88-105 nm, and have bright fluorescence and high stability in severe treatments such as autoclave sterilization and lyophilization. By simultaneously incorporating Rhodamine B and Rhodamine 110 (as reference) dyes at a doping ratio of 1:400 in the NPs, ratiometric FTs with a high sensibility of 7.6%·°C(-1) and a wide temperature sensing range from -20 to 110 °C were obtained. The FTs exhibit good stability in solutions with varied pH, ionic strengths, and viscosities and have similar working curves in both intracellular and extracellular environments. Cellular temperature variations in Hela cells during microwave exposure were successfully monitored using the FTs, indicating their considerable potential applications in the biomedical field.

Treadmilling of a prokaryotic tubulin-like protein, TubZ, required for plasmid stability in Bacillus thuringiensis

PubMed Central

Larsen, Rachel A.; Cusumano, Christina; Fujioka, Akina; Lim-Fong, Grace; Patterson, Paula; Pogliano, Joe

2007-01-01

Prokaryotes rely on a distant tubulin homolog, FtsZ, for assembling the cytokinetic ring essential for cell division, but are otherwise generally thought to lack tubulin-like polymers that participate in processes such as DNA segregation. Here we characterize a protein (TubZ) from the Bacillus thuringiensis virulence plasmid pBtoxis, which is a member of the tubulin/FtsZ GTPase superfamily but is only distantly related to both FtsZ and tubulin. TubZ assembles dynamic, linear polymers that exhibit directional polymerization with plus and minus ends, movement by treadmilling, and a critical concentration for assembly. A point mutation (D269A) that alters a highly conserved catalytic residue within the T7 loop completely eliminates treadmilling and allows the formation of stable polymers at a much lower protein concentration than the wild-type protein. When expressed in trans, TubZ(D269A) coassembles with wild-type TubZ and significantly reduces the stability of pBtoxis, demonstrating a direct correlation between TubZ dynamics and plasmid maintenance. The tubZ gene is in an operon with tubR, which encodes a putative DNA-binding protein that regulates TubZ levels. Our results suggest that TubZ is representative of a novel class of prokaryotic cytoskeletal proteins important for plasmid stability that diverged long ago from the ancient tubulin/FtsZ ancestor. PMID:17510284

The Value Estimation of an HFGW Frequency Time Standard for Telecommunications Network Optimization

NASA Astrophysics Data System (ADS)

Harper, Colby; Stephenson, Gary

2007-01-01

The emerging technology of gravitational wave control is used to augment a communication system using a development roadmap suggested in Stephenson (2003) for applications emphasized in Baker (2005). In the present paper consideration is given to the value of a High Frequency Gravitational Wave (HFGW) channel purely as providing a method of frequency and time reference distribution for use within conventional Radio Frequency (RF) telecommunications networks. Specifically, the native value of conventional telecommunications networks may be optimized by using an unperturbed frequency time standard (FTS) to (1) improve terminal navigation and Doppler estimation performance via improved time difference of arrival (TDOA) from a universal time reference, and (2) improve acquisition speed, coding efficiency, and dynamic bandwidth efficiency through the use of a universal frequency reference. A model utilizing a discounted cash flow technique provides an estimation of the additional value using HFGW FTS technology could bring to a mixed technology HFGW/RF network. By applying a simple net present value analysis with supporting reference valuations to such a network, it is demonstrated that an HFGW FTS could create a sizable improvement within an otherwise conventional RF telecommunications network. Our conservative model establishes a low-side value estimate of approximately 50B USD Net Present Value for an HFGW FTS service, with reasonable potential high-side values to significant multiples of this low-side value floor.

Multiscale assemblage of an ectomycorrhizal fungal community: the influence of host functional traits and soil properties in a 10-ha miombo forest.

PubMed

Bauman, David; Raspé, Olivier; Meerts, Pierre; Degreef, Jérôme; Ilunga Muledi, Jonathan; Drouet, Thomas

2016-10-01

Ectomycorrhizal fungi (EMF) are highly diversified and dominant in a number of forest ecosystems. Nevertheless, their scales of spatial distribution and the underlying ecological processes remain poorly understood. Although most EMF are considered to be generalists regarding host identity, a preference toward functional strategies of host trees has never been tested. Here, the EMF community was characterised by DNA sequencing in a 10-ha tropical dry season forest-referred to as miombo-an understudied ecosystem from a mycorrhizal perspective. We used 36 soil parameters and 21 host functional traits (FTs) as candidate explanatory variables in spatial constrained ordinations for explaining the EMF community assemblage. Results highlighted that the community variability was explained by host FTs related to the 'leaf economics spectrum' (adjusted R(2) = 11%; SLA, leaf area, foliar Mg content), and by soil parameters (adjusted R(2) = 17%), notably total forms of micronutrients or correlated available elements (Al, N, K, P). Both FTs and soil generated patterns in the community at scales ranging from 75 to 375 m. Our results indicate that soil is more important than previously thought for EMF in miombo woodlands, and show that FTs of host species can be better predictors of symbiont distribution than taxonomical identity. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Plate Waste Evaluation of the Farm to School Program.

PubMed

Kropp, Jaclyn D; Abarca-Orozco, Saul J; Israel, Glenn D; Diehl, David C; Galindo-Gonzalez, Sebastian; Headrick, Lauren B; Shelnutt, Karla P

2018-04-01

To investigate the impacts of the Farm to School (FTS) Program on the selection and consumption of fruits and vegetables. Plate waste data were recorded using the visual inspection method before and after implementation of the program. Six elementary schools in Florida: 3 treatment and 3 control schools. A total of 11,262 meal observations of National School Lunch Program (NSLP) participants in grades 1-5. The FTS Program, specifically local procurement of NSLP offerings, began in treatment schools in November, 2015 after the researchers collected preintervention data. The NSLP participants' selection and consumption of fruits and vegetables. Data were analyzed using Mann-Whitney U and proportions tests and difference-in-difference regressions. The NSLP participants at the treatment schools consumed, on average, 0.061 (P = .002) more servings of vegetables and 0.055 (P = .05) more servings of fruit after implementation of the FTS Program. When school-level fixed effects are included, ordinary least squares and tobit regression results indicated that NSLP participants at the treatment schools respectively consumed 0.107 (P < .001) and 0.086 (P < .001) more servings of vegetables, on average, after implementation of the FTS Program. Local procurement positively affected healthy eating. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Flexible transparent and free-standing silicon nanowires paper.

PubMed

Pang, Chunlei; Cui, Hao; Yang, Guowei; Wang, Chengxin

2013-10-09

If the flexible transparent and free-standing paper-like materials that would be expected to meet emerging technological demands, such as components of transparent electrical batteries, flexible solar cells, bendable electronics, paper displays, wearable computers, and so on, could be achieved in silicon, it is no doubt that the traditional semiconductor materials would be rejuvenated. Bulk silicon cannot provide a solution because it usually exhibits brittleness at below their melting point temperature due to high Peierls stress. Fortunately, when the silicon's size goes down to nanoscale, it possesses the ultralarge straining ability, which results in the possibility to design flexible transparent and self-standing silicon nanowires paper (FTS-SiNWsP). However, realization of the FTS-SiNWsP is still a challenging task due largely to the subtlety in the preparation of a unique interlocking alignment with free-catalyst controllable growth. Herein, we present a simple synthetic strategy by gas flow directed assembly of a unique interlocking alignment of the Si nanowires (SiNWs) to produce, for the first time, the FTS-SiNWsP, which consisted of interconnected SiNWs with the diameter of ~10 nm via simply free-catalyst thermal evaporation in a vertical high-frequency induction furnace. This approach opens up the possibility for creating various flexible transparent functional devices based on the FTS-SiNWsP.

Viral and cellular SOS-regulated motor proteins: dsDNA translocation mechanisms with divergent functions.

PubMed

Wolfe, Annie; Phipps, Kara; Weitao, Tao

2014-01-01

DNA damage attacks on bacterial cells have been known to activate the SOS response, a transcriptional response affecting chromosome replication, DNA recombination and repair, cell division and prophage induction. All these functions require double-stranded (ds) DNA translocation by ASCE hexameric motors. This review seeks to delineate the structural and functional characteristics of the SOS response and the SOS-regulated DNA translocases FtsK and RuvB with the phi29 bacteriophage packaging motor gp16 ATPase as a prototype to study bacterial motors. While gp16 ATPase, cellular FtsK and RuvB are similarly comprised of hexameric rings encircling dsDNA and functioning as ATP-driven DNA translocases, they utilize different mechanisms to accomplish separate functions, suggesting a convergent evolution of these motors. The gp16 ATPase and FtsK use a novel revolution mechanism, generating a power stroke between subunits through an entropy-DNA affinity switch and pushing dsDNA inward without rotation of DNA and the motor, whereas RuvB seems to employ a rotation mechanism that remains to be further characterized. While FtsK and RuvB perform essential tasks during the SOS response, their roles may be far more significant as SOS response is involved in antibiotic-inducible bacterial vesiculation and biofilm formation as well as the perspective of the bacteria-cancer evolutionary interaction.

Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

NASA Astrophysics Data System (ADS)

Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

2016-03-01

Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

Efficacy of Lactic Acid, Lactic Acid-Acetic Acid Blends, and Peracetic Acid To Reduce Salmonella on Chicken Parts under Simulated Commercial Processing Conditions.

PubMed

Ramirez-Hernandez, Alejandra; Brashears, Mindy M; Sanchez-Plata, Marcos X

2018-01-01

The poultry processing industry has been undergoing a series of changes as it modifies processing practices to comply with new performance standards for chicken parts and comminuted poultry products. The regulatory approach encourages the use of intervention strategies to prevent and control foodborne pathogens in poultry products and thus improve food safety and protect human health. The present studies were conducted to evaluate the efficacy of antimicrobial interventions for reducing Salmonella on inoculated chicken parts under simulated commercial processing conditions. Chicken pieces were inoculated by immersion in a five-strain Salmonella cocktail at 6 log CFU/mL and then treated with organic acids and oxidizing agents on a commercial rinsing conveyor belt. The efficacy of spraying with six different treatments (sterile water, lactic acid, acetic acid, buffered lactic acid, acetic acid in combination with lactic acid, and peracetic acid) at two concentrations was evaluated on skin-on and skin-off chicken thighs at three application temperatures. Skinless chicken breasts were used to evaluate the antimicrobial efficacy of lactic acid and peracetic acid. The color stability of treated and untreated chicken parts was assessed after the acid interventions. The lactic acid and buffered lactic acid treatments produced the greatest reductions in Salmonella counts. Significant differences between the control and water treatments were identified for 5.11% lactic acid and 5.85% buffered lactic acid in both skin-on and skin-off chicken thighs. No significant effect of treatment temperature for skin-on chicken thighs was found. Lactic acid and peracetic acid were effective agents for eluting Salmonella cells attached to chicken breasts.

Preparation of the 3-monosulphates of cholic acid, chenodeoxycholic acid and deoxycholic acid.

PubMed Central

Haslewood, E S; Haslewood, G A

1976-01-01

1. The 3-sulphates of cholic, chenodeoxycholic and deoxycholic acids were prepared as crystalline disodium salts. 2. The method described shows that it is possible to prepare specific sulphate esters of polyhydroxy bile acids and to remove protecting acyl groups without removing the sulphate. 3. A study of bile acid sulphate solvolysis showed that none of the usual methods give the original bile acid in major yield in a single step. 4. An understanding of the preparation, properties and methods of solvolysis of bile acid sulphates is basic for investigations of cholestasis and liver disease. PMID:938488

Effect of acetic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

PubMed

Xu, Jian; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2014-09-01

An integrated citric acid-methane fermentation process was proposed to solve the problem of extraction wastewater in citric acid fermentation process. Extraction wastewater was treated by anaerobic digestion and then recycled for the next batch of citric acid fermentation to eliminate wastewater discharge and reduce water resource consumption. Acetic acid as an intermediate product of methane fermentation was present in anaerobic digestion effluent. In this study, the effect of acetic acid on citric acid fermentation was investigated and results showed that lower concentration of acetic acid could promote Aspergillus niger growth and citric acid production. 5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) staining was used to quantify the activity of A. niger cells, and the results suggested that when acetic acid concentration was above 8 mM at initial pH 4.5, the morphology of A. niger became uneven and the part of the cells' activity was significantly reduced, thereby resulting in deceasing of citric acid production. Effects of acetic acid on citric acid fermentation, as influenced by initial pH and cell number in inocula, were also examined. The result indicated that inhibition by acetic acid increased as initial pH declined and was rarely influenced by cell number in inocula.

Acid Rain, pH & Acidity: A Common Misinterpretation.

ERIC Educational Resources Information Center

Clark, David B.; Thompson, Ronald E.

1989-01-01

Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

Production of polymalic acid and malic acid by Aureobasidium pullulans fermentation and acid hydrolysis.

PubMed

Zou, Xiang; Zhou, Yipin; Yang, Shang-Tian

2013-08-01

Malic acid is a dicarboxylic acid widely used in the food industry and also a potential C4 platform chemical that can be produced from biomass. However, microbial fermentation for direct malic acid production is limited by low product yield, titer, and productivity due to end-product inhibition. In this work, a novel process for malic acid production from polymalic acid (PMA) fermentation followed by acid hydrolysis was developed. First, a PMA-producing Aureobasidium pullulans strain ZX-10 was screened and isolated. This microbe produced PMA as the major fermentation product at a high-titer equivalent to 87.6 g/L of malic acid and high-productivity of 0.61 g/L h in free-cell fermentation in a stirred-tank bioreactor. Fed-batch fermentations with cells immobilized in a fibrous-bed bioreactor (FBB) achieved the highest product titer of 144.2 g/L and productivity of 0.74 g/L h. The fermentation produced PMA was purified by adsorption with IRA-900 anion-exchange resins, achieving a ∼100% purity and a high recovery rate of 84%. Pure malic acid was then produced from PMA by hydrolysis with 2 M sulfuric acid at 85°C, which followed the first-order reaction kinetics. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application. Copyright © 2013 Wiley Periodicals, Inc.

Molecular and isotopic analyses of the hydroxy acids, dicarboxylic acids, and hydroxydicarboxylic acids of the Murchison meteorite

NASA Astrophysics Data System (ADS)

Cronin, J. R.; Pizzarello, S.; Epstein, S.; Krishnamurthy, R. V.

1993-10-01

The hydroxymonocarboxylic acids, dicarboxylic acids, and hydroxydicarboxylic acids of the Murchison meteorite were analyzed as their tert-butyldimethylsilyl derivatives using combined gas chromatography-mass spectrometry. The hydroxydicarboxylic acids have not been found previously in meteorites. Each class of compounds is numerous with carbon chains up to C8 or C9 and many, if not all, chain and substitution position isomers represented at each carbon number. The alpha-hydroxycarboxylic acids and alpha-hydroxydicarboxylic acids correspond structurally to many of the known meteoritic alpha-aminocarboxylic acids and alpha-aminodicarboxylic acids, a fact that supports the proposal that a Strecker synthesis was involved in the formation of both classes of compounds. Isotopic analyses show these acids to be D-rich relative to terrestrial organic compounds, as expected; however, the hydroxy acids appear to be isotopically lighter than the amino acids with respect to both carbon and hydrogen.

Fourier transform spectroscopy for future planetary missions

NASA Astrophysics Data System (ADS)

Brasunas, John; Kolasinski, John; Kostiuk, Ted; Hewagama, Tilak

2017-01-01

Thermal-emission infrared spectroscopy is a powerful tool for exploring the composition, temperature structure, and dynamics of planetary atmospheres; and the temperature of solid surfaces. A host of Fourier transform spectrometers (FTS) such as Mariner IRIS, Voyager IRIS, and Cassini CIRS from NASA Goddard have made and continue to make important new discoveries throughout the solar system. Future FTS instruments will have to be more sensitive (when we concentrate on the colder, outer reaches of the solar system), and less massive and less power-hungry as we cope with decreasing resource allotments for future planetary science instruments. With this in mind, we have developed CIRS-lite, a smaller version of the CIRS FTS for future planetary missions. We discuss the roadmap for making CIRS-lite a viable candidate for future planetary missions, including the recent increased emphasis on ocean worlds (Europa, Encelatus, Titan) and also on smaller payloads such as CubeSats and SmallSats.

Antibacterial activity of 3-methylbenzo[d]thiazol-methylquinolinium derivatives and study of their action mechanism.

PubMed

Sun, Ning; Du, Ruo-Lan; Zheng, Yuan-Yuan; Guo, Qi; Cai, Sen-Yuan; Liu, Zhi-Hua; Fang, Zhi-Yuan; Yuan, Wen-Chang; Liu, Ting; Li, Xiao-Mei; Lu, Yu-Jing; Wong, Kwok-Yin

2018-12-01

The increasing incidence of multidrug resistant bacterial infection renders an urgent need for the development of new antibiotics. To develop small molecules disturbing FtsZ activity has been recognized as promising approach to search for antibacterial of high potency systematically. Herein, a series of novel quinolinium derivatives were synthesized and their antibacterial activities were investigated. The compounds show strong antibacterial activities against different bacteria strains including MRSA, VRE and NDM-1 Escherichia coli. Among these derivatives, a compound bearing a 4-fluorophenyl group (A2) exhibited a superior antibacterial activity and its MICs to the drug-resistant strains are found lower than those of methicillin and vancomycin. The biological results suggest that these quinolinium derivatives can disrupt the GTPase activity and dynamic assembly of FtsZ, and thus inhibit bacterial cell division and then cause bacterial cell death. These compounds deserve further evaluation for the development of new antibacterial agents targeting FtsZ.

Structures of the Signal Recognition Particle Receptor from the Archaeon Pyrococcus furiosus: Implications for the Targeting Step at the Membrane

PubMed Central

Egea, Pascal F.; Tsuruta, Hiro; de Leon, Gladys P.; Napetschnig, Johanna; Walter, Peter; Stroud, Robert M.

2008-01-01

In all organisms, a ribonucleoprotein called the signal recognition particle (SRP) and its receptor (SR) target nascent proteins from the ribosome to the translocon for secretion or membrane insertion. We present the first X-ray structures of an archeal FtsY, the receptor from the hyper-thermophile Pyrococcus furiosus (Pfu), in its free and GDP•magnesium-bound forms. The highly charged N-terminal domain of Pfu-FtsY is distinguished by a long N-terminal helix. The basic charges on the surface of this helix are likely to regulate interactions at the membrane. A peripheral GDP bound near a regulatory motif could indicate a site of interaction between the receptor and ribosomal or SRP RNAs. Small angle X-ray scattering and analytical ultracentrifugation indicate that the crystal structure of Pfu-FtsY correlates well with the average conformation in solution. Based on previous structures of two sub-complexes, we propose a model of the core of archeal and eukaryotic SRP•SR targeting complexes. PMID:18978942

Nanocrystalline Iron-Ore-Based Catalysts for Fischer-Tropsch Synthesis.

PubMed

Yong, Seok; Park, Ji Chan; Lee, Ho-Tae; Yang, Jung-Il; Hong, SungJun; Jung, Heon; Chun, Dong Hyun

2016-02-01

Nanocrystalline iron ore particles were fabricated by a wet-milling process using an Ultra Apex Mill, after which they were used as raw materials of iron-based catalysts for low-temperature Fischer-Tropsch synthesis (FTS) below 280 degrees C, which usually requires catalysts with a high surface area, a large pore volume, and a small crystallite size. The wet-milling process using the Ultra Apex Mill effectively destroyed the initial crystallite structure of the natural iron ores of several tens to hundreds of nanometers in size, resulting in the generation of nanocrystalline iron ore particles with a high surface area and a large pore volume. The iron-ore-based catalysts prepared from the nanocrystalline iron ore particles effectively catalyzed the low-temperature FTS, displaying a high CO conversion (about 90%) and good C5+ hydrocarbon productivity (about 0.22 g/g(cat)(-h)). This demonstrates the feasibility of using the iron-ore-based catalysts as inexpensive and disposable catalysts for the low-temperature FTS.

Stable doping of carbon nanotubes via molecular self assembly

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

Lee, B.; Chen, Y.; Podzorov, V., E-mail: podzorov@physics.rutgers.edu

2014-10-14

We report a novel method for stable doping of carbon nanotubes (CNT) based on methods of molecular self assembly. A conformal growth of a self-assembled monolayer of fluoroalkyl trichloro-silane (FTS) at CNT surfaces results in a strong increase of the sheet conductivity of CNT electrodes by 60–300%, depending on the CNT chirality and composition. The charge carrier mobility of undoped partially aligned CNT films was independently estimated in a field-effect transistor geometry (~100 cm²V⁻¹s⁻¹). The hole density induced by the FTS monolayer in CNT sheets is estimated to be ~1.8 ×10¹⁴cm⁻². We also show that FTS doping of CNT anodesmore » greatly improves the performance of organic solar cells. This large and stable doping effect, easily achieved in large-area samples, makes this approach very attractive for applications of CNTs in transparent and flexible electronics.« less

Division and dynamic morphology of plastids.

PubMed

Osteryoung, Katherine W; Pyke, Kevin A

2014-01-01

Plastid division is fundamental to the biology of plant cells. Division by binary fission entails the coordinated assembly and constriction of four concentric rings, two internal and two external to the organelle. The internal FtsZ ring and external dynamin-like ARC5/DRP5B ring are connected across the two envelopes by the membrane proteins ARC6, PARC6, PDV1, and PDV2. Assembly-stimulated GTPase activity drives constriction of the FtsZ and ARC5/DRP5B rings, which together with the plastid-dividing rings pull and squeeze the envelope membranes until the two daughter plastids are formed, with the final separation requiring additional proteins. The positioning of the division machinery is controlled by the chloroplast Min system, which confines FtsZ-ring formation to the plastid midpoint. The dynamic morphology of plastids, especially nongreen plastids, is also considered here, particularly in relation to the production of stromules and plastid-derived vesicles and their possible roles in cellular communication and plastid functionality.

Aspartic acid

MedlinePlus

... we eat. Aspartic acid is also called asparaginic acid. Aspartic acid helps every cell in the body work. It ... release Normal nervous system function Plant sources of aspartic acid include: avocado, asparagus, and molasses. Animal sources of ...

Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, Luc

2003-06-24

A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

5-(Tetradecyloxy)-2-furancarboxylic acid and related hypolipidemic fatty acid-like alkyloxyarylcarboxylic acids.

PubMed

Parker, R A; Kariya, T; Grisar, J M; Petrow, V

1977-06-01

5-(Tetradecyloxy)-2-furancarboxylic acid (91, RMI 14514) was found to lower blood lipids and to inhibit fatty acid synthesis with minimal effects on liver weight and liver fat content. This fatty acid-like compound represents a new class of hypolipidemic agent; it is effective in rats and monkeys. The compound resulted from discovery of hypolipidemic activity in certain beta-keto esters, postulation and confirmation of the corresponding benzoic acids as active metabolites, and systematic exploration of the structure--activity relationships.

Acid Rain.

ERIC Educational Resources Information Center

Openshaw, Peter

1987-01-01

Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

Uracil in formic acid hydrolysates of deoxyribonucleic acid

PubMed Central

Schein, Arnold H.

1966-01-01

1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

Passive Ranging Using Infra-Red Atmospheric Attenuation

DTIC Science & Technology

2010-03-01

was the Bomem MR-154 Fourier Transform Spectrometer (FTS). The FTS used both an HgCdTe and InSb detector . For this study, the primary source of data...also outfitted with an HgCdTe and InSb detector . Again, only data from the InSb detector was used. The spectral range of data collected was from...an uncertainty in transmittance of 0.01 (figure 20). This would yield an error in range of 6%. Other sources of error include detector noise or

Flood estimates for ungaged streams in Glacier and Yellowstone National Parks, Montana

USGS Publications Warehouse

Omang, R.J.; Parrett, Charles; Hull, J.A.

1983-01-01

Estimates of 100-year discharges were made at 59 sites in Glacier National Park and 21 sites in Yellowstone National Park to assist the National Park Services in quantifying stream inflow and outflow in the Parks. The estimates were made using regression equations previously developed for Montana. The resulting 100-year discharges are listed in tables; the discharges ranged from 260 to 53,200 cu ft/s in Glacier National Park and from 110 to 27,900 cu ft/s in Yellowstone National Park. (USGS)

Distillation Separation of Hydrofluoric Acid and Nitric Acid from Acid Waste Using the Salt Effect on Vapor-Liquid Equilibrium

NASA Astrophysics Data System (ADS)

Yamamoto, Hideki; Sumoge, Iwao

2011-03-01

This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.

Synthesis of new kojic acid based unnatural α-amino acid derivatives.

PubMed

Balakrishna, C; Payili, Nagaraju; Yennam, Satyanarayana; Uma Devi, P; Behera, Manoranjan

2015-11-01

An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond. Copyright © 2015 Elsevier Ltd. All rights reserved.

Process for the preparation of lactic acid and glyceric acid

DOEpatents

Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

2008-12-02

Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

Short chain fatty acids (butyric acid) and intestinal diseases

PubMed

Manrique Vergara, David; González Sánchez, María Eugenia

2017-10-15

Short chain fatty acids contain up to 6 carbon atoms. Among them, butyric acid stands out for its key role in pathologies with intestinal affectation. Butyric acid is the main energetic substrate of the colonocyte, it stimulates the absorption of sodium and water in the colon, and presents trophic action on the intestinal cells. To review the clinical use of formulations for the oral use of butyric acid. Review of published articles on oral supplementation with butyric acid in intestinal pathologies. The publications mainly deal with the use of oral butyric acid in pathologies involving inflammation and / or alterations of intestinal motility. Highlighting the clinical potential in inflammatory bowel diseases and irritable bowel syndrome. The use of oral supplementation with butyric acid is a promising strategy in pathologies such as inflammatory bowel diseases and irritable bowel syndrome. Bio-available butyric acid formulations with acceptable organoleptic characteristics are being advanced.

The bile acids, deoxycholic acid and ursodeoxycholic acid, regulate colonic epithelial wound healing.

PubMed

Mroz, Magdalena S; Lajczak, Natalia K; Goggins, Bridie J; Keely, Simon; Keely, Stephen J

2018-03-01

The intestinal epithelium constitutes an innate barrier which, upon injury, undergoes self-repair processes known as restitution. Although bile acids are known as important regulators of epithelial function in health and disease, their effects on wound healing processes are not yet clear. Here we set out to investigate the effects of the colonic bile acids, deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA), on epithelial restitution. Wound healing in T 84 cell monolayers grown on transparent, permeable supports was assessed over 48 h with or without bile acids. Cell migration was measured in Boyden chambers. mRNA and protein expression were measured by RT-PCR and Western blotting. DCA (50-150 µM) significantly inhibited wound closure in cultured epithelial monolayers and attenuated cell migration in Boyden chamber assays. DCA also induced nuclear accumulation of the farnesoid X receptor (FXR), whereas an FXR agonist, GW4064 (10 µM), inhibited wound closure. Both DCA and GW4064 attenuated the expression of CFTR Cl - channels, whereas inhibition of CFTR activity with either CFTR- inh -172 (10 µM) or GlyH-101 (25 µM) also prevented wound healing. Promoter/reporter assays revealed that FXR-induced downregulation of CFTR is mediated at the transcriptional level. In contrast, UDCA (50-150 µM) enhanced wound healing in vitro and prevented the effects of DCA. Finally, DCA inhibited and UDCA promoted mucosal healing in an in vivo mouse model. In conclusion, these studies suggest bile acids are important regulators of epithelial wound healing and are therefore good targets for development of new drugs to modulate intestinal barrier function in disease treatment. NEW & NOTEWORTHY The secondary bile acid, deoxycholic acid, inhibits colonic epithelial wound healing, an effect which appears to be mediated by activation of the nuclear bile acid receptor, FXR, with subsequent downregulation of CFTR expression and activity. In contrast, ursodeoxycholic acid promotes

On the acid-base properties of humic acid in soil.

PubMed

Cooke, James D; Hamilton-Taylor, John; Tipping, Edward

2007-01-15

Humic acid was isolated from three contrasting organic-rich soils and acid-base titrations performed over a range of ionic strengths. Results obtained were unlike most humic acid data sets; they showed a greater ionic strength dependency at low pH than at high pH. Forward- and back-titrations with the base and acid revealed hysteresis, particularly at low pH. Previous authors attributed this type of hysteresis to humic acid aggregates-created during the isolation procedure-being redissolved during titration as the pH increased and regarded the results as artificial. However, forward- and back-titrations with organic-rich soils also demonstrated a similar hysteretic behavior. These observations indicate (i) that titrations of humic acid in aggregated form (as opposed to the more usual dissolved form) are more representative of the acid-base properties of humic acid in soil and (ii) that the ionic strength dependency of proton binding in humic acid is related to its degree of aggregation. Thus, the current use of models based on data from dissolved humic substances to predictthe acid-base properties of humic acid in soil under environmental conditions may be flawed and could substantially overestimate their acid buffering capacity.

Characterisation of ATP-dependent Mur ligases involved in the biogenesis of cell wall peptidoglycan in Mycobacterium tuberculosis.

PubMed

Munshi, Tulika; Gupta, Antima; Evangelopoulos, Dimitrios; Guzman, Juan David; Gibbons, Simon; Keep, Nicholas H; Bhakta, Sanjib

2013-01-01

ATP-dependent Mur ligases (Mur synthetases) play essential roles in the biosynthesis of cell wall peptidoglycan (PG) as they catalyze the ligation of key amino acid residues to the stem peptide at the expense of ATP hydrolysis, thus representing potential targets for antibacterial drug discovery. In this study we characterized the division/cell wall (dcw) operon and identified a promoter driving the co-transcription of mur synthetases along with key cell division genes such as ftsQ and ftsW. Furthermore, we have extended our previous investigations of MurE to MurC, MurD and MurF synthetases from Mycobacterium tuberculosis. Functional analyses of the pure recombinant enzymes revealed that the presence of divalent cations is an absolute requirement for their activities. We also observed that higher concentrations of ATP and UDP-sugar substrates were inhibitory for the activities of all Mur synthetases suggesting stringent control of the cytoplasmic steps of the peptidoglycan biosynthetic pathway. In line with the previous findings on the regulation of mycobacterial MurD and corynebacterial MurC synthetases via phosphorylation, we found that all of the Mur synthetases interacted with the Ser/Thr protein kinases, PknA and PknB. In addition, we critically analyzed the interaction network of all of the Mur synthetases with proteins involved in cell division and cell wall PG biosynthesis to re-evaluate the importance of these key enzymes as novel therapeutic targets in anti-tubercular drug discovery.

Characterisation of ATP-Dependent Mur Ligases Involved in the Biogenesis of Cell Wall Peptidoglycan in Mycobacterium tuberculosis

PubMed Central

Munshi, Tulika; Gupta, Antima; Evangelopoulos, Dimitrios; Guzman, Juan David; Gibbons, Simon; Keep, Nicholas H.; Bhakta, Sanjib

2013-01-01

ATP-dependent Mur ligases (Mur synthetases) play essential roles in the biosynthesis of cell wall peptidoglycan (PG) as they catalyze the ligation of key amino acid residues to the stem peptide at the expense of ATP hydrolysis, thus representing potential targets for antibacterial drug discovery. In this study we characterized the division/cell wall (dcw) operon and identified a promoter driving the co-transcription of mur synthetases along with key cell division genes such as ftsQ and ftsW. Furthermore, we have extended our previous investigations of MurE to MurC, MurD and MurF synthetases from Mycobacterium tuberculosis. Functional analyses of the pure recombinant enzymes revealed that the presence of divalent cations is an absolute requirement for their activities. We also observed that higher concentrations of ATP and UDP-sugar substrates were inhibitory for the activities of all Mur synthetases suggesting stringent control of the cytoplasmic steps of the peptidoglycan biosynthetic pathway. In line with the previous findings on the regulation of mycobacterial MurD and corynebacterial MurC synthetases via phosphorylation, we found that all of the Mur synthetases interacted with the Ser/Thr protein kinases, PknA and PknB. In addition, we critically analyzed the interaction network of all of the Mur synthetases with proteins involved in cell division and cell wall PG biosynthesis to re-evaluate the importance of these key enzymes as novel therapeutic targets in anti-tubercular drug discovery. PMID:23555903

Do prokaryotes contain microtubules?

NASA Technical Reports Server (NTRS)

Bermudes, D.; Hinkle, G.; Margulis, L.

1994-01-01

In eukaryotic cells, microtubules are 24-nm-diameter tubular structures composed of a class of conserved proteins called tubulin. They are involved in numerous cell functions including ciliary motility, nerve cell elongation, pigment migration, centrosome formation, and chromosome movement. Although cytoplasmic tubules and fibers have been observed in bacteria, some with diameters similar to those of eukaryotes, no homologies to eukaryotic microtubules have been established. Certain groups of bacteria including azotobacters, cyanobacteria, enteric bacteria, and spirochetes have been frequently observed to possess microtubule-like structures, and others, including archaebacteria, have been shown to be sensitive to drugs that inhibit the polymerization of microtubules. Although little biochemical or molecular biological information is available, the differences observed among these prokaryotic structures suggest that their composition generally differs among themselves as well as from that of eukaryotes. We review the distribution of cytoplasmic tubules in prokaryotes, even though, in all cases, their functions remain unknown. At least some tend to occur in cells that are large, elongate, and motile, suggesting that they may be involved in cytoskeletal functions, intracellular motility, or transport activities comparable to those performed by eukaryotic microtubules. In Escherichia coli, the FtsZ protein is associated with the formation of a ring in the division zone between the newly forming offspring cells. Like tubulin, FtsZ is a GTPase and shares with tubulin a 7-amino-acid motif, making it a promising candidate in which to seek the origin of tubulins.

Effects of dietary conjugated linoleic acid and linoleic:linolenic acid ratio on polyunsaturated fatty acid status in laying hens.

PubMed

Du, M; Ahn, D U; Sell, J L

2000-12-01

A study was conducted to determine the effects of dietary conjugated linoleic acid (CLA) and the ratio of linoleic:linolenic acid on long-chain polyunsaturated fatty acid status. Thirty-two 31-wk-old White Leghorn hens were randomly assigned to four diets containing 8.2% soy oil, 4.1% soy oil + 2.5% CLA (4.1% CLA source), 4.1% flax oil + 2.5% CLA, or 4.1% soy oil + 4.1% flax oil. Hens were fed the diets for 3 wk before eggs and tissues were collected for the study. Lipids were extracted from egg yolk and tissues, classes of egg yolk lipids were separated, and fatty acid concentrations of total lipids, triglyceride, phosphatidylethanolamine, and phosphatidylcholine were analyzed by gas chromatography. The concentrations of monounsaturated fatty acids and non-CLA polyunsaturated fatty acids were reduced after CLA feeding. The amount of arachidonic acid was decreased after CLA feeding in linoleic acid- and linolenic acid-rich diets, but amounts of eicosapentaenoic acid and docosahexaenoic acid were increased in the linolenic-rich diet, indicating that the synthesis or deposition of long-chain n-3 fatty acids was accelerated after CLA feeding. The increased docosahexaenoic acid and eicosapentaenoic acid contents in lipid may be compensation for the decreased arachidonic acid content. Dietary supplementation of linoleic acid increased n-6 fatty acid levels in lipids, whereas linolenic acid increased n-3 fatty acid levels. Results also suggest that CLA might not be elongated to synthesize long-chain fatty acids in significant amounts. The effect of CLA in reducing the level of n-6 fatty acids and promoting the level of n-3 fatty acids could be related to the biological effects of CLA.

Correcting the extended-source calibration for the Herschel-SPIRE Fourier-transform spectrometer

NASA Astrophysics Data System (ADS)

Valtchanov, I.; Hopwood, R.; Bendo, G.; Benson, C.; Conversi, L.; Fulton, T.; Griffin, M. J.; Joubaud, T.; Lim, T.; Lu, N.; Marchili, N.; Makiwa, G.; Meyer, R. A.; Naylor, D. A.; North, C.; Papageorgiou, A.; Pearson, C.; Polehampton, E. T.; Scott, J.; Schulz, B.; Spencer, L. D.; van der Wiel, M. H. D.; Wu, R.

2018-03-01

We describe an update to the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) Fourier-transform spectrometer (FTS) calibration for extended sources, which incorporates a correction for the frequency-dependent far-field feedhorn efficiency, ηff. This significant correction affects all FTS extended-source calibrated spectra in sparse or mapping mode, regardless of the spectral resolution. Line fluxes and continuum levels are underestimated by factors of 1.3-2 in thespectrometer long wavelength band (447-1018 GHz; 671-294 μm) and 1.4-1.5 in the spectrometer short wavelength band (944-1568 GHz; 318-191 μm). The correction was implemented in the FTS pipeline version 14.1 and has also been described in the SPIRE Handbook since 2017 February. Studies based on extended-source calibrated spectra produced prior to this pipeline version should be critically reconsidered using the current products available in the Herschel Science Archive. Once the extended-source calibrated spectra are corrected for ηff, the synthetic photometry and the broad-band intensities from SPIRE photometer maps agree within 2-4 per cent - similar levels to the comparison of point-source calibrated spectra and photometry from point-source calibrated maps. The two calibration schemes for the FTS are now self-consistent: the conversion between the corrected extended-source and point-source calibrated spectra can be achieved with the beam solid angle and a gain correction that accounts for the diffraction loss.

Optimising recovery after surgery: Predictors of early discharge and hospital readmission.

PubMed

Carter, Jonathan; Philp, Shannon; Wan, King M

2016-10-01

Fast track surgery (FTS) programs minimise the stress response after surgery and allow for enhanced recovery. To document the frequency and incidence of adverse events in patients enrolled on a FTS program and to investigate factors associated with shorter length of stay and readmission to hospital. A seven-year updated surgical audit of patients undergoing laparotomy for suspected or confirmed malignancy on a FTS program. Five hundred and fifty patients comprise the study group. Average age and body mass index (BMI) were 55 years and 28, respectively. Mean length of stay (LOS) was 3.4 days with 194 (35%) patients discharged on day 2. Six (1%) patients had confirmed venous thromboembolism (VTE), three of whom were diagnosed on pre-operative imaging. Overall, transfusion rate was 5%. Adverse events in decreasing frequency were hospital readmission (4%) and significant wound infection (3%). All other adverse events were uncommon with rates <0.5%. Factors associated with a discharge on or after day 3 include age, pathology, Eastern Cooperative Oncology Group performance status, incision type, operating time, blood transfusion and cyclo-oxygenase 2 inhibitors. Factors associated with hospital readmission include longer operating time, performance of lymph node sampling/dissection, longer LOS, development of wound infection, febrile morbidity, return to the operating room, unplanned intensive care unit admission and presence of other complications. Patients managed by a FTS protocol can expect enhanced outcomes when compared to historical controls. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

PopZ identifies the new pole, and PodJ identifies the old pole during polar growth in Agrobacterium tumefaciens

PubMed Central

Grangeon, Romain; Zupan, John R.; Anderson-Furgeson, James; Zambryski, Patricia C.

2015-01-01

Agrobacterium tumefaciens elongates by addition of peptidoglycan (PG) only at the pole created by cell division, the growth pole, whereas the opposite pole, the old pole, is inactive for PG synthesis. How Agrobacterium assigns and maintains pole asymmetry is not understood. Here, we investigated whether polar growth is correlated with novel pole-specific localization of proteins implicated in a variety of growth and cell division pathways. The cell cycle of A. tumefaciens was monitored by time-lapse and superresolution microscopy to image the localization of A. tumefaciens homologs of proteins involved in cell division, PG synthesis and pole identity. FtsZ and FtsA accumulate at the growth pole during elongation, and improved imaging reveals FtsZ disappears from the growth pole and accumulates at the midcell before FtsA. The L,D-transpeptidase Atu0845 was detected mainly at the growth pole. A. tumefaciens specific pole-organizing protein (Pop) PopZAt and polar organelle development (Pod) protein PodJAt exhibited dynamic yet distinct behavior. PopZAt was found exclusively at the growing pole and quickly switches to the new growth poles of both siblings immediately after septation. PodJAt is initially at the old pole but then also accumulates at the growth pole as the cell cycle progresses suggesting that PodJAt may mediate the transition of the growth pole to an old pole. Thus, PopZAt is a marker for growth pole identity, whereas PodJAt identifies the old pole. PMID:26324921

NFATC3-PLA2G15 Fusion Transcript Identified by RNA Sequencing Promotes Tumor Invasion and Proliferation in Colorectal Cancer Cell Lines.

PubMed

Jang, Jee-Eun; Kim, Hwang-Phill; Han, Sae-Won; Jang, Hoon; Lee, Si-Hyun; Song, Sang-Hyun; Bang, Duhee; Kim, Tae-You

2018-06-14

This study was designed to identify novel fusion transcripts (FTs) and their functional significance in colorectal cancer lines. We performed paired-end RNA sequencing of 28 colorectal cancer (CRC) cell lines. FT candidates were identified using TopHat-fusion, ChimeraScan, and FusionMap tools and further experimental validation was conducted through reverse transcription-polymerase chain reaction and Sanger sequencing. FT was depleted in human CRC line and the effects on cell proliferation, cell migration, and cell invasion were analyzed. 1,380 FT candidates were detected through bioinformatics filtering. We selected 6 candidate FTs, including 4 inter-chromosomal and 2 intra-chromosomal FTs and each FT was found in at least 1 of the 28 cell lines. Moreover, when we tested 19 pairs of CRC tumor and adjacent normal tissue samples, NFATC3-PLA2G15 FT was found in 2. Knockdown of NFATC3-PLA2G15 using siRNA reduced mRNA expression of epithelial-mesenchymal transition (EMT) markers such as vimentin, twist, and fibronectin and increased mesenchymal-epithelial transition markers of E-cadherin, claudin-1, and FOXC2 in colo-320 cell line harboring NFATC3-PLA2G15 FT. The NFATC3-PLA2G15 knockdown also inhibited invasion, colony formation capacity, and cell proliferation. These results suggest that that NFATC3-PLA2G15 FTs may contribute to tumor progression by enhancing invasion by EMT and proliferation.

A Novel Fractional Order Model for the Dynamic Hysteresis of Piezoelectrically Actuated Fast Tool Servo

PubMed Central

Zhu, Zhiwei; Zhou, Xiaoqin

2012-01-01

The main contribution of this paper is the development of a linearized model for describing the dynamic hysteresis behaviors of piezoelectrically actuated fast tool servo (FTS). A linearized hysteresis force model is proposed and mathematically described by a fractional order differential equation. Combining the dynamic modeling of the FTS mechanism, a linearized fractional order dynamic hysteresis (LFDH) model for the piezoelectrically actuated FTS is established. The unique features of the LFDH model could be summarized as follows: (a) It could well describe the rate-dependent hysteresis due to its intrinsic characteristics of frequency-dependent nonlinear phase shifts and amplitude modulations; (b) The linearization scheme of the LFDH model would make it easier to implement the inverse dynamic control on piezoelectrically actuated micro-systems. To verify the effectiveness of the proposed model, a series of experiments are conducted. The toolpaths of the FTS for creating two typical micro-functional surfaces involving various harmonic components with different frequencies and amplitudes are scaled and employed as command signals for the piezoelectric actuator. The modeling errors in the steady state are less than ±2.5% within the full span range which is much smaller than certain state-of-the-art modeling methods, demonstrating the efficiency and superiority of the proposed model for modeling dynamic hysteresis effects. Moreover, it indicates that the piezoelectrically actuated micro systems would be more suitably described as a fractional order dynamic system.

Bartonella vinsonii subsp. berkhoffii and B. henselae in dogs.

PubMed

Müller, A; Soto, F; Sepúlveda, M; Bittencourt, P; Benevenute, J L; Ikeda, P; Machado, R Z; André, M R

2018-05-06

This study aimed to molecularly survey Bartonella in dogs from Chile. Quantitative real-time PCR (qPCR) for Bartonella spp. based on nuoG gene was performed in 139 blood samples taken from dogs belonging to rural localities of the Valdivia Province, Los Ríos region, southern Chile. nuoG qPCR-positive samples were submitted to conventional PCR assays for ftsZ, gltA, rpoB and nuoG genes and sequencing for speciation and phylogenetic analysis. Based upon qPCR results, Bartonella spp. occurrence in dogs was 4.3% (6/139). Out of six nuoG qPCR-positive samples, six, three, two and none showed positive results in cPCR assays based on gltA, ftsZ, rpoB and nuoG genes, respectively. Consistent sequencing results were obtained only for the ftsZ gene from sample #1532 (GeneBank accession number: MG252491), and gltA gene from samples #1535 (MG252490) and #1532 (148 bp fragment that was not deposited in GenBank). Phylogenetic analysis of ftsZ and gltA genes allowed speciation of two nuoG-positive samples, one as Bartonella vinsonii subsp. berkhoffii and the other as B. henselae. Bartonella vinsonii subsp. berkhoffii and B. henselae are detected for the first time in dogs from Chile, highlighting the importance of the canine population as a source of zoonotic agents and potential infection risk to humans.

Consolidated List of Debarred, Suspended, and Ineligible Contractors as of April 10, 1985.

DTIC Science & Technology

1985-04-01

Administration code 202, but Fdral officials calling lon distance Juan L . Smith should use the FTS (Federal "blecommunications 523-4873 Sterr) or AUTVN (Automatic...Washington, DC 20405 Belle N. Davis (Codes A and B) Attention: Mrs. Juan L . Smith 475-8025 FTS/(202) 523-4873 3 r, % .1 𔄀 ’ % Cause and Treatment Codes...for violation of1961, the I is effctve win 0O; It Imposed the Buy American Act (41 U.S.C. 10b(b)) 4 -k % =",W""-- l m. .°6 ."._. ’ t. ,+... W LML

Active Curved Polymers Form Vortex Patterns on Membranes.

PubMed

Denk, Jonas; Huber, Lorenz; Reithmann, Emanuel; Frey, Erwin

2016-04-29

Recent in vitro experiments with FtsZ polymers show self-organization into different dynamic patterns, including structures reminiscent of the bacterial Z ring. We model FtsZ polymers as active particles moving along chiral, circular paths by Brownian dynamics simulations and a Boltzmann approach. Our two conceptually different methods point to a generic phase behavior. At intermediate particle densities, we find self-organization into vortex structures including closed rings. Moreover, we show that the dynamics at the onset of pattern formation is described by a generalized complex Ginzburg-Landau equation.

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, Luc

1999-01-01

A process of preparing an acid addition salt of delta-aminolevulinic acid comprising: dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures thereof to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing said alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Involvement of Abscisic Acid in PSII Photodamage and D1 Protein Turnover for Light-Induced Premature Senescence of Rice Flag Leaves

PubMed Central

Wang, Fubiao; Liu, Jianchao; Chen, Minxue; Zhou, Lujian; Li, Zhaowei; Zhao, Qian; Pan, Gang; Zaidi, Syed-Hassan-Raza; Cheng, Fangmin

2016-01-01

D1 protein in the PSII reaction center is the major target of photodamage, and it exhibits the highest turnover rate among all the thylakoid proteins. In this paper, rice psf (premature senescence of flag leaves) mutant and its wild type were used to investigate the genotype-dependent alteration in PSII photo-damage and D1 protein turnover during leaf senescence and its relation to ABA accumulation in senescent leaves. The symptom and extent of leaf senescence of the psf mutant appeared to be sunlight-dependent under natural field condition. The psf also displayed significantly higher levels of ABA accumulation in senescent leaves than the wild type. However, the premature senescence lesion of psf leaves could be alleviated by shaded treatment, concomitantly with the strikingly suppressed ABA level in the shaded areas of flag leaves. The change in ABA concentration contributed to the regulation of shade-delayed leaf senescence. The participation of ABA in the timing of senescence initiation and in the subsequent rate of leaf senescence was closely associated with PSII photodamage and D1 protein turnover during leaf senescence, in which the transcriptional expression of several key genes (psbA, psbB, psbC and OsFtsH2) involved in D1 protein biosynthesis and PSII repair cycle was seriously suppressed by the significantly increased ABA level. This response resulted in the low rate of D1 protein synthesis and impaired repair recovery in the presence of ABA. The psf showed evidently decreased D1 protein amount in the senescent leaves. Both the inhibition of de novo synthesized D1 protein and the slow rate of proteolytic removal for the photodamaged D1 protein was among the most crucial steps for the linkage between light-dependent leaf senescence and the varying ABA concentration in psf mutant leaves. OsFtsH2 transcriptional expression possibly played an important role in the regulation of D1 protein turnover and PSII repair cycle in relation to ABA mediated leaf

Understanding Acid Rain

ERIC Educational Resources Information Center

Damonte, Kathleen

2004-01-01

The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, L.

1999-05-25

A process is disclosed for preparing an acid addition salt of delta-aminolevulinic acid comprising. The process involves dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing the alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Validation of a multi-analyte HPLC-DAD method for determination of uric acid, creatinine, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid and 2-methylhippuric acid in human urine.

PubMed

Remane, Daniela; Grunwald, Soeren; Hoeke, Henrike; Mueller, Andrea; Roeder, Stefan; von Bergen, Martin; Wissenbach, Dirk K

2015-08-15

During the last decades exposure sciences and epidemiological studies attracts more attention to unravel the mechanisms for the development of chronic diseases. According to this an existing HPLC-DAD method for determination of creatinine in urine samples was expended for seven analytes and validated. Creatinine, uric acid, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid, and 2-methylhippuric acid were separated by gradient elution (formate buffer/methanol) using an Eclipse Plus C18 Rapid Resolution column (4.6mm×100mm). No interfering signals were detected in mobile phase. After injection of blank urine samples signals for the endogenous compounds but no interferences were detected. All analytes were linear in the selected calibration range and a non weighted calibration model was chosen. Bias, intra-day and inter-day precision for all analytes were below 20% for quality control (QC) low and below 10% for QC medium and high. The limits of quantification in mobile phase were in line with reported reference values but had to be adjusted in urine for homovanillic acid (45mg/L), niacinamide 58.5(mg/L), and indole-3-acetic acid (63mg/L). Comparison of creatinine data obtained by the existing method with those of the developed method showing differences from -120mg/L to +110mg/L with a mean of differences of 29.0mg/L for 50 authentic urine samples. Analyzing 50 authentic urine samples, uric acid, creatinine, hippuric acid, and 2-methylhippuric acid were detected in (nearly) all samples. However, homovanillic acid was detected in 40%, niacinamide in 4% and indole-3-acetic acid was never detected within the selected samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Long open-path measurements of greenhouse gases in air using near-infrared Fourier transform spectroscopy

NASA Astrophysics Data System (ADS)

Griffith, David W. T.; Pöhler, Denis; Schmitt, Stefan; Hammer, Samuel; Vardag, Sanam N.; Platt, Ulrich

2018-03-01

In complex and urban environments, atmospheric trace gas composition is highly variable in time and space. Point measurement techniques for trace gases with in situ instruments are well established and accurate, but do not provide spatial averaging to compare against developing high-resolution atmospheric models of composition and meteorology with resolutions of the order of a kilometre. Open-path measurement techniques provide path average concentrations and spatial averaging which, if sufficiently accurate, may be better suited to assessment and interpretation with such models. Open-path Fourier transform spectroscopy (FTS) in the mid-infrared region, and differential optical absorption spectroscopy (DOAS) in the UV and visible, have been used for many years for open-path spectroscopic measurements of selected species in both clean air and in polluted environments. Near infrared instrumentation allows measurements over longer paths than mid-infrared FTS for species such as greenhouse gases which are not easily accessible to DOAS.In this pilot study we present the first open-path near-infrared (4000-10 000 cm-1, 1.0-2.5 µm) FTS measurements of CO2, CH4, O2, H2O and HDO over a 1.5 km path in urban Heidelberg, Germany. We describe the construction of the open-path FTS system, the analysis of the collected spectra, several measures of precision and accuracy of the measurements, and the results a four-month trial measurement period in July-November 2014. The open-path measurements are compared to calibrated in situ measurements made at one end of the open path. We observe significant differences of the order of a few ppm for CO2 and a few tens of ppb for CH4 between the open-path and point measurements which are 2 to 4 times the measurement repeatability, but we cannot unequivocally assign the differences to specific local sources or sinks. We conclude that open-path FTS may provide a valuable new tool for investigations of atmospheric trace gas composition in

Development of imaging FTS for astronomy

NASA Astrophysics Data System (ADS)

Grandmont, Frederic

2002-05-01

The Next Generation Space Telescope project in its early definition phases has given birth to many innovations in instrumentation for astronomy by providing funding for industries in an area often considered less lucrative and hence of lower interest. New alliances were formed with universities and institutions and the knowledge exchange lead to very interesting new concepts. The Imaging version of the Fourier Transform Spectrometer (IFTS), a derivative of the classical Michelson interferometer that has been used successfully in spectroscopy for decades, was introduced in military applications in the mid 80's with small FPA (- 2 X 4).

Atmospheric limb sounding with imaging FTS

NASA Astrophysics Data System (ADS)

Friedl-Vallon, Felix; Riese, Martin; Preusse, Peter; Oelhaf, Hermann; Fischer, Herbert

Imaging Fourier transform spectrometers in the thermal infrared are a promising new class of sensors for atmospheric science. The availability of fast and sensitive large focal plane arrays with appropriate spectral coverage in the infrared region allows the conception and construction of innovative sensors for Nadir and Limb geometry. Instruments in Nadir geometry have already reached prototype status (e.g. Geostationary Imaging Fourier Transform Spectrometer / U. Wisconsin and NASA) or are in Phase A study (infrared sounding mission on Meteosat third generation / ESA and EUMETSAT). The first application of the new technical possibilities to atmospheric limb sounding from space, the Imaging Michelson Interferometer for Passive Atmospheric Sounding (IMIPAS), is currently studied by industry in the context of preparatory work for the next set of ESA earth explorers. The scientific focus of the instrument is on the processes controlling the composition of the mid/upper troposphere and lower stratosphere. The instrument concept of IMIPAS has been conceived at the research centres Karlsruhe and J¨lich. The development of a precursor instrument (GLORIA-AB) at these research institutions u started already in 2005. The instrument will be able to fly on board of various airborne platforms. First scientific missions are planned for the second half of the year 2009 on board the new German research aircraft HALO. This airborne sensor serves its own scientific purpose, but it also provides a test bed to learn about this new instrument class and its peculiarities and to learn to exploit and interpret the wealth of information provided by a limb imaging IR Fourier transform spectrometer. The presentation will discuss design considerations and challenges for GLORIA-AB and put them in the context of the planned satellite application. It will describe the solutions found, present first laboratory figures of merit for the prototype instrument and outline the new scientific possibilities.

A GC-ECD method for estimation of free and bound amino acids, gamma-aminobutyric acid, salicylic acid, and acetyl salicylic acid from Solanum lycopersicum (L.).

PubMed

Meher, Hari Charan; Gajbhiye, Vijay T; Singh, Ghanendra

2011-01-01

A gas chromatograph with electron capture detection method for estimation of selected metabolites--amino acids (free and bound), gamma-aminobutyric acid (GABA), salicylic acid (SA), and acetyl salicylic acid (ASA) from tomato--is reported. The method is based on nitrophenylation of the metabolites by 1-fluoro-2, 4-dinitrobenzene under aqueous alkaline conditions to form dinitophenyl derivatives. The derivatives were stable under the operating conditions of GC. Analysis of bound amino acids comprised perchloric acid precipitation of protein, alkylation (carboxymethylation) with iodoacetic acid, vapor-phase hydrolysis, and derivatization with 1-fluoro-2,4-dinitrobenzene in that order. The metabolites were resolved in 35 min, using a temperature-programmed run. The method is rapid, sensitive, and precise. It easily measured the typical amino acids (aspartate, asparagine, glutamate, glutamine, alanine, leucine, lysine, and phenylalanine) used for identification and quantification of a protein, resolved amino acids of the same mass (leucine and isoleucine), satisfactorily measured sulfur amino acid (methionine, cystine, and cysteine), and quantified GABA, SA, and ASA, as well. The developed method was validated for specificity, linearity, and precision. It has been applied and recommended for estimation of 25 metabolites from Solanum lycopersicum (L.).

Targeted metabolomics analysis reveals the association between maternal folic acid supplementation and fatty acids and amino acids profiles in rat pups.

PubMed

Liu, Zhipeng; Liu, Rui; Chou, Jing; Yu, Jiaying; Liu, Xiaowei; Sun, Changhao; Li, Ying; Liu, Liyan

2018-07-15

Maternal diet during pregnancy can influence offspring's health by affecting development and metabolism. This study aimed to analyze the influence of maternal folic acid (FA) supplementation on the metabolism of rat pups using targeted metabolomics. Twenty female rats were randomly assigned to a FA supplementation (FAS group, n = 10) or control group (n = 10), which were fed AIN93G diet with 2 or 10 mg/kg FA, respectively. We then measured amino acids and their derivatives, biogenic amines, and fatty acids in the female rats and their pups by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC/MS-MS) and gas chromatography-mass spectrometry (GC/MS-MS). In maternal rats, the significant changes of three metabolites (proline, γ-aminobutyric acid and esterified octadecatetraenoic acid, P < 0.05) were observed in FAS group. For the rat pups, FAS pups had significantly lower homocysteine and higher FA levels than control pups. The lower levels of amino acids (leucine, isoleucine, serine, proline) were obtained in FAS pups. Furthermore, there were the decreased esterified fatty acids (arachidonic acid, eicosapentaenoic acid, and docosatetraenoic acid) and free fatty acids (oleic acid, linoleic acid, γ-linolenic acid, octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid and selacholeic acid) in FAS pups. Metabolic changes in the FAS pups were characterized by changes in fatty acids and amino acids. These results suggested that FA supplementation during pregnancy influenced amino acids and fatty acids metabolism in rat pups. This study provides new insights into the regulation of amino acids and fatty acids metabolism during early life. Copyright © 2018 Elsevier B.V. All rights reserved.

All-trans retinoic acid regulates hepatic bile acid homeostasis

PubMed Central

Yang, Fan; He, Yuqi; Liu, Hui-Xin; Tsuei, Jessica; Jiang, Xiaoyue; Yang, Li; Wang, Zheng-Tao; Wan, Yu-Jui Yvonne

2014-01-01

Retinoic acid (RA) and bile acids share common roles in regulating lipid homeostasis and insulin sensitivity. In addition, the receptor for RA (retinoid x receptor) is a permissive partner of the receptor for bile acids, farnesoid x receptor (FXR/NR1H4). Thus, RA can activate the FXR-mediated pathway as well. The current study was designed to understand the effect of all-trans RA on bile acid homeostasis. Mice were fed an all-trans RA-supplemented diet and the expression of 46 genes that participate in regulating bile acid homeostasis was studied. The data showed that all-trans RA has a profound effect in regulating genes involved in synthesis and transport of bile acids. All-trans RA treatment reduced the gene expression levels of Cyp7a1, Cyp8b1, and Akr1d1, which are involved in bile acid synthesis. All-trans RA also decreased the hepatic mRNA levels of Lrh-1 (Nr5a2) and Hnf4α (Nr2a1), which positively regulate the gene expression of Cyp7a1 and Cyp8b1. Moreover, all-trans RA induced the gene expression levels of negative regulators of bile acid synthesis including hepatic Fgfr4, Fxr, and Shp (Nr0b2) as well as ileal Fgf15. All-trans RA also decreased the expression of Abcb11 and Slc51b, which have a role in bile acid transport. Consistently, all-trans RA reduced hepatic bile acid levels and the ratio of CA/CDCA, as demonstrated by liquid chromatography-mass spectrometry. The data suggest that all-trans RA-induced SHP may contribute to the inhibition of CYP7A1 and CYP8B1, which in turn reduces bile acid synthesis and affects lipid absorption in the gastrointestinal tract. PMID:25175738

Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

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

Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher

An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted inmore » liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.« less

Acid Earth--The Global Threat of Acid Pollution.

ERIC Educational Resources Information Center

McCormick, John

Acid pollution is a major international problem, but the debate it has elicited has often clouded the distinction between myth and facts. This publication attempts to concerning the acid pollution situation. This publication attempts to identify available facts. It is the first global review of the problem of acid pollution and the first to…