Respiratory Turn-Over and Metabolic Compartments: From the Design of Tracer Experiments to the Characterization of Respiratory Substrate-Supply Systems

2017 ◽  
pp. 161-179 ◽  
Author(s):  
Hans Schnyder ◽  
Ulrike Ostler ◽  
Christoph A. Lehmeier
Keyword(s):  
Substrate Supply ◽  
Turn Over ◽  
Supply Systems ◽  
Metabolic Compartments ◽  
Tracer Experiments

Turbine Stator Well CFD Studies: Effects of Coolant Supply Geometry on Cavity Sealing Performance

2010 ◽  
Vol 133 (2) ◽  
Author(s):  
Antonio Andreini ◽  
Riccardo Da Soghe ◽  
Bruno Facchini
Keyword(s):  
Air Cooling ◽  
Sector Model ◽  
Engine Efficiency ◽  
Air Supply ◽  
Sealing Performance ◽  
Computational Fluid Dynamics Cfd ◽  
Cooling Air ◽  
Supply Systems

The increase of aeroengine performance through the improvement of aerodynamic efficiency of core flow is becoming more and more difficult to achieve. However, there are still some devices that could be improved to enhance global engine efficiency. Particularly, investigations on the internal air cooling systems may lead to a reduction of cooling air with a direct benefit to the overall performance. At the same time, further investigations on heat transfer mechanisms within turbine cavities may help to optimize cooling air flows, saving engine life duration. This paper presents a computational fluid dynamics (CFD) study aimed at the characterization of the effects of different geometries for cooling air supply within turbine cavities on wall thermal effectiveness and sealing mass flow rate. Several sealing air supply geometries were considered in order to point out the role of cooling air injection position, swirl number, and jet penetration on the cavities’ sealing performance. Steady state calculations were performed using two different computational domains: the first consists of a sector model of the whole turbine including the second stator well, while the second is a cut-down model of the stator well. Thanks to the simplified geometry of the test rig with respect to actual engines, the study has pointed out clear design suggestions regarding the effects of geometry modification of cooling air supply systems.

scholarly journals PCR characterization of isolates from various endemic areas: diversity and turn over of Plasmodium falciparum populations are correlated with transmission

1994 ◽  
Vol 89 (suppl 2) ◽  
pp. 9-12 ◽  
Author(s):  
Pierre Daubersies ◽  
Selma Sallenave-Sales ◽  
Jean Francois Trape ◽  
Lucie Raharimalala ◽  
Christophe Rogier ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Endemic Areas ◽  
Turn Over

Identification of opportunities to improve efficiency by water consumption assessment

2007 ◽  
Vol 7 (4) ◽  
pp. 57-63
Author(s):  
S.L. Diás ◽  
H. Lucas ◽  
M.do Céu Almeida ◽  
H. Alegre ◽  
M. Vriato ◽  
...  
Keyword(s):  
Water Supply ◽  
Water Consumption ◽  
Demand Management ◽  
Water Supply Systems ◽  
Management Options ◽  
Emergency Situations ◽  
Usage Patterns ◽  
Supply Systems ◽  
Water Uses

Characterization of water demand can be of large value for the management of water supply systems. Especially when water resources are limited, permanently or seasonally, the identification of the types of consumers and its characteristics are essential to identify opportunities to promote efficiency and demand management options. For each customer category, information to be obtained includes individual uses, typical daily usage patterns (average and dispersion), specific characteristics and magnitude. Knowledge and systematization of water uses also provides data to improve water balance and thus allows reducing uncertainty in losses estimation. In this paper, a study carried out in Algarve, a region where stress on water supply resources has been increasing, is presented aiming at better characterise water consumption in the region to improve response both to normal and in emergency situations.

Purification of a Single Peptide with Vitamin K Epoxide to Vitamin K and Vitamin K to Vitamin KH2 Activity.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 331-331
Author(s):  
Pei-hsuan Chu ◽  
Teng-yi Huang ◽  
Jason Williams ◽  
Darrel W. Stafford
Keyword(s):  
Vitamin K ◽  
Complete Recovery ◽  
Vitamin K Epoxide Reductase ◽  
Vitamin K Cycle ◽  
The Us ◽  
Epoxide Reductase ◽  
Measurable Activity ◽  
Turn Over ◽  
Single Peptide

Abstract More than 21 million prescriptions for warfarin are written yearly in the US. Yet, in spite of its importance, vitamin K epoxide reductase (VKOR), the target of warfarin, has resisted purification since its identification in 1972. We report the first successful purification and reconstitution of activity of a recombinant human vitamin K epoxide reductase. A series of detergents were screened to determine that best for solubilization of VKOR from microsomes. Detergents tested that were effective in solubilization of VKOR also led to loss of measurable activity. This loss of activity supports our previous prediction that VKOR is embedded in and requires a membrane environment for enzymatic activity. The short-chain phospholipid, DHPC (1,2-Dihexanoyl-sn-Glycero-3-Phosphocholine) was the detergent of choice to efficiently extract VKOR from the microsomes, even though this reagent completely inhibited enzyme activity. Partial reconstitution was achieved on-column by washing with 0.4 % dioleoylphosphatidylcholine/0.4% deoxycholate. Complete recovery of activity was achieved by removing the deoxycholate through dialysis in the presence of the reducing reagent, THP (Tris(hydroxypropyl)phosphine). During dialysis, the solution became cloudy indicating the formation of membrane-like structure. Purified recombinant VKOR is ~21 kDa (~18.5 kDa + tag); fully active; and over 93% pure. The concentration of warfarin for 50% inhibition is the same for purified protein and microsomes. It has been reported and assumed that VKOR is a multi-subunit enzyme. Our results, however, suggest that a single peptide can accomplish the reaction. The trace amounts of contaminating proteins were identified by mass spectrometry; however, none are apparently relevant to the VKOR reaction. Moreover, the turn-over number of purified VKOR (0.25 sec-1 is approximately two-fold higher than microsomes and about 10 fold higher than the turnover number of gamma-glutamyl carboxylase for CO2 addition. In addition to the vitamin K epoxide to vitamin K reaction, our results also indicate that VKOR can efficiently convert vitamin K to vitamin K epoxide. Our results suggest that ancillary proteins (other than a thioredoxin-like enzyme) are not necessary for full VKOR activity. This purification will allow further characterization of VKOR in relation to other components of the vitamin K cycle and should facilitate its structural determination.

Characterization of mortars from ancient and traditional water supply systems in Sicily

2008 ◽  
Vol 92 (1) ◽  
pp. 323-330 ◽  
Author(s):  
G. Rizzo ◽  
Laura Ercoli ◽  
B. Megna ◽  
Maria Parlapiano
Keyword(s):  
Water Supply ◽  
Water Supply Systems ◽  
Supply Systems

scholarly journals Synthesis and Characterization of Novel Phyto-Mediated Catalyst, and Its Application for a Selective Oxidation of (VAL) into Vanillin under Visible Light

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 839 ◽  
Author(s):  
Afnan Al-Hunaiti ◽  
Qassem Mohaidat ◽  
Ibrahim Bsoul ◽  
Sami Mahmood ◽  
Deeb Taher ◽  
...  
Keyword(s):  
Visible Light ◽  
Selective Oxidation ◽  
Vanillyl Alcohol ◽  
Reaction Conditions ◽  
Excellent Photocatalytic Activity ◽  
Lignin Model ◽  
Turn Over Frequency ◽  
Average Size ◽  
Turn Over

Here, we report an efficient and highly selective oxidation of lignin model substrate using phyto-mediated ZnFe2O4 nanoparticle using Boswellia carterii extract. The nanocatalyst with an average size of 8 nm showed excellent photocatalytic activity of the synthesized carbonyl containing products under visible light irradiation. The catalytic activity and selectivity towards oxidation of vanillyl alcohol to vanillin with selectivity up to 99% at conversion over 98% and turn-over frequency values up to 1600 h−1 were obtained in the presence of H2O2 and base. The cubic spinel nano-ZnFe2O4 catalyst was characterized by powder-XRD, FESEM, HR-TEM and Mössbauer analysis. The demonstrated catalyst was robust and stable under the reaction conditions. Furthermore, it was easy to be separated from the reaction mixture and be reused for subsequent reactions up to 5 times without significant reactivity or selectivity loss.

scholarly journals Sorbing tracer experiments in a crystalline rock fracture at Äspö (Sweden): 1. Experimental setup and microscale characterization of retention properties

2007 ◽  
Vol 43 (10) ◽  
Author(s):  
H. Widestrand ◽  
J. Byegård ◽  
V. Cvetkovic ◽  
E.-L. Tullborg ◽  
A. Winberg ◽  
...  
Keyword(s):  
Rock Fracture ◽  
Crystalline Rock ◽  
Experimental Setup ◽  
Tracer Experiments

Identification and characterization of the cysteine and serine proteinases of the trematode,Haplometra cylindraceaand determination of their haemoglobinase activity

Parasitology ◽  
1994 ◽  
Vol 108 (5) ◽  
pp. 595-601 ◽  
Author(s):  
S. J. Hawthorne ◽  
D. W. Halton ◽  
B. Walker
Keyword(s):  
Cysteine Proteinase ◽  
Cathepsin L ◽  
Serine Proteinase ◽  
Hydrolytic Activity ◽  
Molecular Weights ◽  
Affinity Reagent ◽  
Turn Over

SummaryThe excreted/secreted proteinases ofHaplometra cylindraceamaintainedin vitro, were found to hydrolyse the fluorogenic substrates, Z-ArgArg-NHMec and Z-PheArg-NHMec. This activity was shown to be typically that of cysteine proteinases, as turn-over of both substrates could be blocked by pre-incubation with peptidyl diazomethyl ketones. The biotinylated affinity reagent, biotin-Phe Ala-DMK, used in combination with Z-PheTyr(OBut)-DMK, was employed for the labelling and characterization of these cysteine proteinase activities. Three cathepsin B-like species were detected, with molecular weights of 48, 22–23 and 14 kDa, together with a cathepsin L-like enzyme, with a molecular weight of 55 kDa. The proteinases were also found to have hydrolytic activity towards the substrate, Z-GlyGlyArg-NHMec, which could be blocked by pre-incubation with either of the serine proteinase-selective reagents, Z-ArgP(OPh)2, or biotin-LysP(OPh)2, showing the activity to be trypsin-like. Using the biotinylated affinity label to characterize the trypsin-like enzymes revealed two molecular species with molecular weights of 20 and 24 kDa.

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