Mars surface transport systems utilizing in situ hydrogen

2014 ◽  
Author(s):  
Robert L. Ash ◽  
Sean M. Hancock ◽  
Jake Tynis
Keyword(s):  
Transport Systems ◽  
Surface Transport

Effect of heavy metals on the leaf disc ferricyanide reduction in cucumber

2009 ◽  
Vol 57 (3) ◽  
pp. 307-320
Author(s):  
G. Rabnecz ◽  
G. Záray ◽  
L. Lévai ◽  
F. Fodor
Keyword(s):  
Heavy Metals ◽  
Nutrient Solution ◽  
Chlorophyll Concentration ◽  
Leaf Disc ◽  
Transport Systems ◽  
Ferricyanide Reduction ◽  
Plasma Membrane Electron Transport ◽  
Significant Linear Correlation ◽  
Drastic Effect

The effect of heavy metals on the leaf plasma membrane electron transport systems was investigated in connection with the tissue Fe concentration in Fe-sufficient and Fe-deficient cucumber leaves. Ten M μPb in the nutrient solution inhibited leaf ferricyanide reduction by 20–26%, whereas 10 M μCd had a more drastic effect, with 80–83% inhibition. Ferricyanide reduction decreased by 14% when 1 mM Pb was applied in situ by vacuum infiltration into control leaf discs, whereas it decreased by 40% when 0.1 mM Cd was applied. Ferricyanide reduction was completely inhibited by 1 mM Cd. The ferricyanide reduction values were correlated with the heavy metal, Fe and chlorophyll concentrations in the leaves. A significant linear correlation was only found with the chlorophyll concentration. The data suggest that there are also direct effects on membranebound reductases, but these are of less significance. Using differentially Fe-deficient plants (grown with 0 to 300 nM Fe in the nutrient solution), a chlorophyll concentration of 0.9–1.0 mg g −1 fresh weight was estimated as the threshold for achieving the ferricyanide reduction levels found in the controls.

Exploring the relationship between organic deposition resulting from marshes and autogenic scales in deltaic stratigraphy

2021 ◽  
Author(s):  
Jose Silvestre ◽  
Kelly Sanks ◽  
Sam Zapp ◽  
Dutt Ripul ◽  
John Shaw ◽  
...  
Keyword(s):  
Sea Level ◽  
Sediment Accumulation ◽  
Organic Production ◽  
Transport Systems ◽  
Constant Input ◽  
Kaolinite Clay ◽  
Clastic Sediment ◽  
Organic Sediment ◽  
Stratigraphic Architecture

<p>Many deltas contain extensive marshes, typically defined as laterally extensive, low energy settings tied to a narrow elevation window around sea level. Biological activity in marshes results in in-situ organic sediment accumulation that has the potential to be stored in the sedimentary record. However, it is unclear how marshes interact with channels that transport the clastic sediment and typically control autogenic stratigraphic architecture. We present results from a physical experiment designed to explore the coupled evolution of marshes and deltas over geologic timescales. In the experiment, deltaic channels self-organized due to constant input rates of water and clastic sediment that experience constant long-term accommodation production through sea-level rise. A low bulk density kaolinite clay was deposited on the delta-top following rules developed by the ecology community for in-situ organic production. The kaolinite clay serves as a proxy for the in-situ organic sediments in overbank regions. As such, the autogenic processes of the clastic transport system, which influence elevation relative to sea-level, also exert a control on the scales of preserved organic-rich strata. We quantify the fraction of the organic sediment proxy in the fluvio-deltaic deposit to define a transfer function between the accumulation of organic sediment and its preservation beneath the morphodynamically active layer. We also use synthetic stratigraphy and images of the preserved strata to characterize the spatial arrangements of organic strata, and the influence of marshes on the resulting arrangement of channel bodies. Initial findings suggest that the thickest seams are located near the mean shoreline but extend significant distances from this location due to autogenic shoreline transgressions and regressions. Quantifying these trends will inform our understanding of how in-situ organic sediment accumulation influences clastic transport systems and the structure of deltaic stratigraphy.</p>

Rat lung type II cell and lamellar body: elemental composition in situ

1988 ◽  
Vol 254 (5) ◽  
pp. C614-C620 ◽  
Author(s):  
R. G. Eckenhoff ◽  
A. P. Somlyo
Keyword(s):  
Elemental Composition ◽  
Lamellar Body ◽  
Cell Types ◽  
Transport Systems ◽  
Alveolar Type ◽  
Type Ii ◽  
Freeze Dried ◽  
Type Ii Cell ◽  
The Difference

We determined the in situ elemental composition of alveolar type II cells (ATII) and lamellar bodies (LB) with electronprobe microanalysis (EPMA) of freeze-dried unstained cryosections (100-200 nm) obtained from lungs frozen in anesthetized rats. Twenty-nine ATII from seven rats were subjected to EPMA. Cytoplasmic (Cyto) composition was the following (in mmol/kg dry wt, mean +/- SE, n = 30): 136 +/- 14.1 Na, 60 +/- 2.8 Mg, 549 +/- 34.8 P, 278 +/- 10.5 S, 158 +/- 7.3 Cl, 525 +/- 26.4 K, and 6.6 +/- 0.9 Ca. LB composition was the following (n = 66): 44 +/- 4.0 Na, 7.9 +/- 0.8 Mg, 1,060 +/- 25.0 P, 79 +/- 4.8 S, 64 +/- 3.6 Cl, 114 +/- 4.1 K, and 30 +/- 0.9 Ca. P and S concentrations were consistent with previous biochemical determinations of phospholipid and protein content of isolated LBs. LBs contain significantly more Ca and less Mg than Cyto. Ca correlated significantly with LB P but not S concentration, and the reported low Ca binding affinity of similar phospholipid mixtures implies a high LB free Ca concentration. Ca was significantly higher in apical and exocytotic LBs compared with those in the perinuclear region. Differences between LB and Cyto monovalent ion concentrations are not entirely due to the difference in hydration revealed by significantly lower K-Cl ratios in LBs. The relative excess of Cl and Ca in LB suggests that these ions may be distributed by active transport systems known to be present in the Golgi apparatus and in Golgi-derived organelles of other cell types.

scholarly journals Metagenomic and Metaproteomic Insights into Photoautotrophic and Heterotrophic Interactions in a Synechococcus Culture

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Qiang Zheng ◽  
Yu Wang ◽  
Jiayao Lu ◽  
Wenxin Lin ◽  
Feng Chen ◽  
...  
Keyword(s):  
Organic Matter ◽  
Bacterial Community ◽  
Heterotrophic Bacteria ◽  
Bacterial Community Composition ◽  
Complex Compounds ◽  
Transport Systems ◽  
Bacterial Strains ◽  
Bacterial Populations ◽  
Coculture System

ABSTRACT Microbial photoautotroph-heterotroph interactions underlie marine food webs and shape ecosystem diversity and structure in upper ocean environments. Here, bacterial community composition, lifestyle preference, and genomic- and proteomic-level metabolic characteristics were investigated for an open ocean Synechococcus ecotype and its associated heterotrophs over 91 days of cocultivation. The associated heterotrophic bacterial assembly mostly constituted five classes, including Flavobacteria, Bacteroidetes, Phycisphaerae, Gammaproteobacteria, and Alphaproteobacteria. The seven most abundant taxa/genera comprised >90% of the total heterotrophic bacterial community, and five of these displayed distinct lifestyle preferences (free-living or attached) and responses to Synechococcus growth phases. Six high-quality genomes, including Synechococcus and the five dominant heterotrophic bacteria, were reconstructed. The only primary producer of the coculture system, Synechococcus, displayed metabolic processes primarily involved in inorganic nutrient uptake, photosynthesis, and organic matter biosynthesis and release. Two of the flavobacterial populations, Muricauda and Winogradskyella, and an SM1A02 population, displayed preferences for initial degradation of complex compounds and biopolymers, as evinced by high abundances of TonB-dependent transporters (TBDTs), glycoside hydrolase, and peptidase proteins. Polysaccharide utilization loci present in the flavobacterial genomes influence their lifestyle preferences and close associations with phytoplankton. In contrast, the alphaproteobacterium Oricola sp. population mainly utilized low-molecular-weight dissolved organic carbon (DOC) through ATP-binding cassette (ABC), tripartite ATP-independent periplasmic (TRAP), and tripartite tricarboxylate transporter (TTT) transport systems. The heterotrophic bacterial populations exhibited complementary mechanisms for degrading Synechococcus-derived organic matter and driving nutrient cycling. In addition to nutrient exchange, removal of reactive oxygen species and vitamin trafficking might also contribute to the maintenance of the Synechococcus-heterotroph coculture system and the interactions shaping the system. IMPORTANCE The high complexity of in situ ecosystems renders it difficult to study marine microbial photoautotroph-heterotroph interactions. Two-member coculture systems of picocyanobacteria and single heterotrophic bacterial strains have been thoroughly investigated. However, in situ interactions comprise far more diverse heterotrophic bacterial associations with single photoautotrophic organisms. In the present study, combined metagenomic and metaproteomic data supplied the metabolic potentials and activities of uncultured dominant bacterial populations in the coculture system. The results of this study shed light on the nature of interactions between photoautotrophs and heterotrophs, improving our understanding of the complexity of in situ environments.

STOL Aircraft—A Perspective

1968 ◽  
Vol 72 (685) ◽  
pp. 11-33 ◽  
Author(s):  
R. D. Hiscocks
Keyword(s):  
High Performance ◽  
Transport Systems ◽  
Total System ◽  
Operating Environment ◽  
Surface Transport ◽  
Transport Aircraft ◽  
Air Space ◽  
The Cost ◽  
Lifting System ◽  
Design And Manufacture

Summary The interest in Canada in the design and manufacture of utility aircraft with a short take-off and landing (STOL) performance may be traced back to the difficulties of surface transport in the early development of the country and the widespread use of bush aircraft. The leading characteristics of the STOL aircraft are examined with particular reference to design features essential to a short take-off and landing. The choice of powerplants and lifting systems is discussed with emphasis on the requirements for powered lift in the larger sizes of aircraft. The augmentor-wing is described as an example of an integrated propulsion lifting system with promise of a high performance. The phases of the take-off, transition, climb and landing manoeuvre are reviewed to illustrate the relative importance of various parameters in design and operation. The importance is stressed of good stability characteristics and effective controls for manoeuvring in a confined air space and a consistent landing performance. The requirements of a para-military mobile force tor a rapid response, deployment overseas and transportation in an area are examined. Some estimates are given of the probability of finding suitable airstrips in a particular region and the cost of constructing new airfields in a dynamic situation. The operating environment in potentially troubled areas of the world is examined briefly to provide guidance in design. The costs of a military supply system are discussed using various modes of transport which include trucks, helicopters, STOL and conventional transport aircraft with results which suggest that the system employing STOL aircraft in the tactical theatre has advantages in cost and effectiveness. Attention is drawn to the growing requirement for shorthaul, commuter and air taxi aircraft with STOL characteristics. Reference is made to the increases in air travel and the widespread use of large transport aircraft which have encouraged the movement of airports from urban centres at a time when city growth and congestion render surface transport increasingly difficult. The relative costs of commercial systems using the helicopter and STOL aircraft are examined. It is shown that the cost of STOL ports is not an excessive portion of total system costs when all factors are taken into account. Some forecasts are made as to future development trends in transport systems using STOL aircraft.

Airflow problems related to surface transport systems

1971 ◽  
Vol 269 (1199) ◽  
pp. 327-333 ◽  
Keyword(s):  
Ground Plane ◽  
Aircraft Design ◽  
Modern Society ◽  
Transport Systems ◽  
Transient Effects ◽  
Surface Transport ◽  
High Speeds ◽  
Moving Vehicles ◽  
Railway System ◽  
New Applications

Until comparatively recently surface transport engineering managed to get along reasonably well while paying only slight attention to aerodynamic problems. Speeds were low, and on the whole designs were determined by other considerations. But recent increases in the power, speed and size of vehicles, and the increasing dependence of modern society on transport systems that are completely reliable, have begun to focus attention on the need to devote more effort to understanding the movement of the atmosphere past moving vehicles, and over or through stationary portions of transport systems such as roads, bridges and tunnels. This paper aims to illustrate the problems that can arise in the field of surface transport. They tend to be in some ways more awkward than those encountered in the design of aircraft. The proximity of the ground plane, the frequent inability to introduce symmetry or two-dimensional geometry as simplifying factors and the emphasis on transient effects all make the analysis difficult to handle theoretically, or in some cases to explore experimentally. This being so, it is hardly a matter for surprise that the surface transport field is still relatively neglected, particularly in comparison with the more obviously glamorous field of aircraft design. Nevertheless, the sums involved in making an existing railway system perform satisfactorily at high speeds from an aerodynamic viewpoint may well be substantial. Tunnel ventilation will certainly become of increasing significance as tunnelling technology improves and as the falling cost of tunnelling opens up new applications for city transport and for road crossings of water and mountain barriers. And motorways in exposed places must be made as safe and weather-proof as knowledge permits. A case can certainly be made out for reconsidering our priorities in aerodynamic research.

The Radiation Inactivation of Membrane Transport Systems

Physiology ◽  
1989 ◽  
Vol 4 (4) ◽  
pp. 134-138
Author(s):  
R Beliveau ◽  
M Potier
Keyword(s):  
Transport Systems ◽  
Physical Interaction ◽  
Protein Subunits ◽  
Radiation Inactivation ◽  
Protein Molecules ◽  
Crucial Information ◽  
Function Relationship ◽  
Relationship Of ◽  
Membrane Transport Systems

Relatively few methods are available to estimate the size of proteins in biological membranes. The radiation inactivation method does not require purified preparation and allows the study in situ of physical interaction between protein subunits, providing crucial information about the structure-function relationship of protein molecules.

scholarly journals In situ mechanical and electrical characterization of composite-integrated thin film-supercapacitors

2018 ◽  
Vol 188 ◽  
pp. 01028
Author(s):  
Jan Petersen ◽  
Sebastian Geier ◽  
Peter Wierach ◽  
Martin Wiedemann
Keyword(s):  
Thin Film ◽  
Manufacturing Process ◽  
Mechanical Load ◽  
Bending Test ◽  
Electrical Performance ◽  
Transport Systems ◽  
Large Temperature ◽  
Energy Storage Devices ◽  
Mechanical Loads

Future transport systems will be powered more and more electrically. Generally the energy is stored in batteries. To reduce system weight and volume, multifunctional materials could be the answer. Therefore materials with the capability to store electric energy and to bear mechanical loads, need to be investigated to understand the effect of mechanical load on such structural integrated energy storage devices. In this work a thin film-supercapacitor is build up and integrated within a composite structure. The capacitor is developed to withstand the manufacturing process of a glass-fibre reinforced polymer and to carry mechanical loads, while simultaneously storing electrical energy. By using a supercapacitor housing, which is compatible to epoxy resin, a strong bonding is achieved, leading to a mechanical robust multifunctional composite. An electrolyte with large temperature window, low vapour pressure and the compatibility to a carbon based electrodes is chosen, to meet the requirement regarding the manufacturing process of the supercapacitor itself and the fibre reinforced composite. The composites with integrated thin film-supercapacitor as well as a set of reference samples are mechanically characterised in tensile and four-point bending test. In situ measurements are performed to investigate the influence of mechanical load on the electrical performance.

scholarly journals Method for analysis and comparison in planning urban surface transport systems

2012 ◽  
Author(s):  
R. Bozzo ◽  
M. Canepa ◽  
C. Carnevali ◽  
R. Genova ◽  
G. Priano
Keyword(s):  
Urban Surface ◽  
Transport Systems ◽  
Surface Transport
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