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The Effect of Carbon Monoxide on the Growth of an Aquatic Streptomycete

Description: The major purpose of this investigation was to determine the effect of carbon monoxide on the development of various morphological phases of a single isolate of the aquatic streptomycetes and to elucidate the physiological differences between terminal respiration in the primary and secondary stages. A secondary purpose was to repeat the work of Michael Lee Higgins involving the effect of anaerobiosis on the growth of the organism.
Date: August 1966
Creator: Francisco, Donald Edward
Partner: UNT Libraries

Respiratory physiology of the reedfish, Calamoichthys calabaricus

Description: Bimodal resprometry was conducted on reedfish, Calamoichthys caabricus, acclimated to 25C and 33C. The relative proportion of aerial respiration to the total oxygen consumption increased with acclimation temperature (p<0.05), directly correlated to activity (p<0.01) and was inversely correlated with dissolved oxygen (p<0.01). Reedfish survived aquatic hypoxia (<1 ppm) for days solely using aerial respiration. Not surprisingly, reedfish exhibited no behavioral avoidance of aquatic hypoxia when given access to air.
Date: December 1982
Creator: Pettit, Michael J. (Michael James)
Partner: UNT Libraries

Determination of the Number of Double Bonds in Less-Than-Milligram Amounts of Unsaturated Fatty Acids by Catalytic Hydrogenation in the Warburg Apparatus

Description: Report discussing the determination of the number of olefinic double bonds in less-than-milligram amounts of unsaturated fatty acid derivatives using Barcroft-Warburg tissue respirometer as a manometric microhydrogenation apparatus.
Date: April 1949
Creator: Mead, James F. & Howton, David R.
Partner: UNT Libraries Government Documents Department

Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
Date: August 1971
Creator: Lin, Chen-hsiung
Partner: UNT Libraries

Relationship Between Ventilation and Oxygen Uptake at 40% And 85% of Peak Oxygen Uptake in 18-35-Year-Old Women Using the Arm Crank Ergometer

Description: This study investigated whether or not a relationship exists between ventilation and oxygen uptake at 40% and 85% of V02 peak intensity in 30 upper body fit and 30 unfit 18- 35-year-old women. The correlations between ventilation and oxygen uptake at 40% of peak intensity for the fit group (r = -.51) and the unfit group (r = -.48) were modestly negative. At 85% intensity the relationship between ventilation and oxygen uptake in the two groups was -.44 and -.66, respectively. The lower correlations between ventilation and oxygen uptake observed at the 85% level of peak intensity among the unfit group could be due to a lower ventilatory threshold (66% = fit; 49% = unfit), lesser local muscle changes, along with reduced lactate and C02 management; all of which would be improved with training.
Date: May 1988
Creator: Zervopoulos, Peter C. (Peter Cosmas)
Partner: UNT Libraries

A genomic analysis of the archael system Ignicoccus hospitalis-Nanoarchaeum equitans

Description: BACKGROUND: The relationship between the hyperthermophiles Ignicoccus hospitalis and Nanoarchaeum equitans is the only known example of a specific association between two species of Archaea. Little is known about the mechanisms that enable this relationship. RESULTS: We sequenced the complete genome of I. hospitalis and found it to be the smallest among independent, free-living organisms. A comparative genomic reconstruction suggests that the I. hospitalis lineage has lost most of the genes associated with a heterotrophic metabolism that is characteristic of most of the Crenarchaeota. A streamlined genome is also suggested by a low frequency of paralogs and fragmentation of many operons. However, this process appears to be partially balanced by lateral gene transfer from archaeal and bacterial sources. CONCLUSIONS: A combination of genomic and cellular features suggests highly efficient adaptation to the low energy yield of sulfur-hydrogen respiration and efficient inorganic carbon and nitrogen assimilation. Evidence of lateral gene exchange between N. equitans and I. hospitalis indicates that the relationship has impacted both genomes. This association is the simplest symbiotic system known to date and a unique model for studying mechanisms of interspecific relationships at the genomic and metabolic levels.
Date: September 1, 2008
Creator: Sun, Hui; Anderson, Iain; Makarova, Kira S.; Elkins, James G.; Ivanova, Natalia; Wall, Mark A. et al.
Partner: UNT Libraries Government Documents Department

Time-windows-based filtering method for near-surface detection of leakage from geologic carbon sequestration sites

Description: We use process-based modeling techniques to characterize the temporal features of natural biologically controlled surface CO{sub 2} fluxes and the relationships between the assimilation and respiration fluxes. Based on these analyses, we develop a signal-enhancing technique that combines a novel time-window splitting scheme, a simple median filtering, and an appropriate scaling method to detect potential signals of leakage of CO{sub 2} from geologic carbon sequestration sites from within datasets of net near-surface CO{sub 2} flux measurements. The technique can be directly applied to measured data and does not require subjective gap filling or data-smoothing preprocessing. Preliminary application of the new method to flux measurements from a CO{sub 2} shallow-release experiment appears promising for detecting a leakage signal relative to background variability. The leakage index of ?2 was found to span the range of biological variability for various ecosystems as determined by observing CO{sub 2} flux data at various control sites for a number of years.
Date: February 28, 2010
Creator: Pan, L.; Lewicki, J.L.; Oldenburg, C.M. & Fischer, M.L.
Partner: UNT Libraries Government Documents Department

Cardio-Respiratory Ontogeny and the Transition to Bimodal Respiration in an Air Breathing Fish: Morphological and Physiological Development in Normoxia and Hypoxia.

Description: As selection pressures exist for not only adults, but for every life history stage, it is important to understand how environmental factors shape developing animals. Despite the significance placed on aquatic hypoxia as a driving force in the evolution of air breathing, this is the first known study to examine the effects of hypoxia on cardio-respiratory ontogeny of an air breathing fish. Blue gouramis are obligatory air breathing fish that possess a labyrinth-like structure that serves as the air breathing organ. Gouramis were reared for up to 90 d in normoxia or hypoxia, and morphological and physiological development was observed. Hypoxic larvae had increased lamellar and labyrinth organ surface areas. Bradycardia and increased gill ventilation rates were observed when larvae from either rearing group were briefly exposed to hypoxia. Hypoxic larvae also showed a reduced heart rate and gill ventilation rate in the absence of a hypoxic stimulus, possibly indicative of a more comprehensive, long-term respiratory plasticity. The similarity of routine oxygen consumption between rearing groups suggests that metabolic demand did not change for hypoxic larvae, but that they were more efficient at oxygen acquisition. This is further supported by increased resistance time of hypoxic gouramis to extreme hypoxia. The onset of air breathing was between 20 and 25 d post-fertilization, and was not affected by either rearing or exposure environment. It may be that this behavior is associated with the inability of smaller larvae to successfully overcome water surface tension, rather than with the necessity of aerial respiration at this stage. Hypoxia is commonly experienced by most air breathing fishes, and studies of hypoxia-induced developmental effects may provide critical insights into the evolution of air breathing. The studies presented here provide novel data on the plasticity of cardio-respiratory development of an air breathing fish reared in hypoxia, and can ...
Date: August 2009
Creator: Blank, Tara M.
Partner: UNT Libraries

Respiratory Protective Devices Approved by the Bureau of Mines as of December 31, 1968: A Revision of Information Circular 8281

Description: Report issued by the U.S. Bureau of Mines discussing a revision on the breathing devices approved for use in mines and mineral industries. As stated in the abstract, "this publication lists the respiratory protective devices approved by the Bureau of mines as of December 31, 1968, and the names and addresses of their manufacturers" (p. 1). This report includes tables.
Date: 1969
Creator: Schutz, R. H. & Kloos, E. J.
Partner: UNT Libraries Government Documents Department

The Effects of Biofeedback and Verbal Feedback on the Training and Maintenance of Diaphragmatic Breathing

Description: The purpose of this study was to evaluate the effects of a computer program on the training and maintenance of diaphragmatic breathing. The biofeedback portion was visual computer training and the results were displayed concurrently with participants' breathing responses to monitor display. The verbal feedback portion was praise that was given and recorded when participants responded with predominantly diaphragmatic breathing at the scheduled moment and response instruction that was given when participants responded with predominantly thoracic breathing. The results of this study indicate the computer program's effectiveness needs to be increased by supplementation with verbal feedback.
Date: May 2003
Creator: Armstrong, Earl E.
Partner: UNT Libraries

Hematocrit, hematocrit Regulation and its effect on oxygen consumption in the late stage chicken embryo (Gallus domesticus).

Description: Hematocrit and hematocrit regulation have the potential to affect developing embryos. To examine the ability of chicken embryos at day 15 to regulate hematocrit, they were subjected to either repeated saline injections (5% of total blood volume) or repeated blood removal (5% of total blood volume). Embryos showed an ability to maintain hematocrit (~20%) despite blood volume increases up to 115% of initial blood volume. Embryos were not able to maintain hematocrit in the face of dramatic blood volume loss. Oxygen consumption of embryos could be affected by their level of hematocrit. To examine this, chicken embryos at day 15, 16, and 17 of incubation were given a high hematocrit (~50-60%) sample of blood (400 μl) to artificially increase the hematocrit of the embryos (~10-12%). Despite the increase in oxygen availability, when monitored over a period of six hours, embryos showed no difference (0.36 ± 0.01 (ml O2 - min-1- egg-1) in metabolism from baseline measurements at day 15, 16 and 17.
Date: August 2004
Creator: Khorrami, Sheva
Partner: UNT Libraries

An Analysis of Respiratory Mechanisms Controlling Exercise Hyperpnea During Cycle Ergometry Conducted at Selected Workloads and Pedal Frequencies

Description: Respiratory and metabolic patterns in response to variations in exercise workload (WL) and pedal frequency (RPM) were examined in 10 healthy males. Each subject performed WLs of low (L), moderate (M) and high (H) intensity, equivalent to 25%, 50% and 75% V02 m a x at 7 pedal frequencies (40, 50, 60, 70, 80, 90 and 100 RPM). ANOVA ( 3 X 7 design) indicated that WL and RPM had independent and significant effects on all respiratory and metabolic measures; i.e., the greater the WL and RPM, the higher the HR, V02, VC02, Ve, Fb, Vt, Vt/Ti, Vt/Te and Ti/TtQt and the lower the Ti and Te. However, analysis of the interaction effect revealed different response patterns for Fb, Vt, Ti, Vt/Ti, Vt/Te and Ve among the WLs. During L-WL, increases in RPM produced increases in Ve which were due to progressive increases in both Fb and Vt. However, during M-WL and H-WL, increases in RPM produced increases in Ve which were accomplished by a constant Vt and a progressive increase in Fb. My findings suggest that during low WLs, the signal for Vt is dependent on rate of contraction, while during M-WL and H-WL, the signal for Vt appears to depend on force of contraction and is independent of increasing RPM. When comparing the L-WL and M-WL, alterations in Ve, Fb, Vt/Ti and Vt/Te in relation to increases in pedal frequency were additive. However, when these two lower WLs were compared to the H-WL, the interaction between pedal frequency and Ve, Fb, Vt/Ti and Vt/Te was multiplicative. In addition, the interaction between WL and RPM on Vt and Ti was additive when comparing the M-WL and H-WL and multiplicative when these two lower WLs were compared to the H-WL. Correlation analysis indicated that for all WLs, Te was more ...
Date: December 1986
Creator: Wise, Charles Hamilton
Partner: UNT Libraries

Using model analyses and surface-atmosphere exchange measurements from the Howland AmeriFlux Site in Maine, USA, to improve understanding of forest ecosystem C cycling

Description: Summary of research carried out under Interagency Agreement DE-AI02-07ER64355 with the USDA Forest Service at the Howland Forest AmeriFlux site in central Maine. Includes a list of publications resulting in part or whole from this support.
Date: March 25, 2013
Creator: Hollinger, David Y.; Davidson, Eric A.; Richardson, Andrew D.; Dail, D. B. & Scott, N.
Partner: UNT Libraries Government Documents Department

The Breathing Orbital Valence Bond Method in Diffusion Monte Carlo: C-H Bond Dissociation ofAcetylene

Description: This study explores the use of breathing orbital valence bond (BOVB) trial wave functions for diffusion Monte Carlo (DMC). The approach is applied to the computation of the carbon-hydrogen (C-H) bond dissociation energy (BDE) of acetylene. DMC with BOVB trial wave functions yields a C-H BDE of 132.4 {+-} 0.9 kcal/mol, which is in excellent accord with the recommended experimental value of 132.8 {+-} 0.7 kcal/mol. These values are to be compared with DMC results obtained with single determinant trial wave functions, using Hartree-Fock orbitals (137.5 {+-} 0.5 kcal/mol) and local spin density (LDA) Kohn-Sham orbitals (135.6 {+-} 0.5 kcal/mol).
Date: May 30, 2008
Creator: Domin, D.; Braida, Benoit & Lester Jr., William A.
Partner: UNT Libraries Government Documents Department


Description: Fatty acids have a reversible inhibitory effect on respiration and on photosynthetic action. They investigated the influence of octanoic acid on the photosynthetic bacteria Rhodopseudomonas spheroids R-26. From the spectroscopic data they conclude that a less efficient energy transfer and decoupling of the light harvesting pigment system from the energy converting reaction center is responsible for the inhibitory effect.
Date: May 1, 1971
Creator: Steffea, Hans & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department


Description: The gas exchange by barley leaves of oxygen, carbon dioxide, and added radiocarbon dioxide has been measured in a closed system, with the following results: 1. Carbon dioxide follows different but not necessarily independent paths in photosynthesis and light respiration. 2. The carbon of newly formed photosynthetic intermediates is not available for respiration while the light is on, but becomes immediately respirable in the dark, The enhancement of dark respiration after a light period is largely due to built-up ''photosynthates.'' 3. Photosynthesis proceeds at a measurable rate even at the lowest CO{sub 2} pressures observed (0.03 mm Hg). There is no evidence for a ''threshold'' concentration of carbon dioxide for the reaction; at the lowest concentrations reached, respiration exactly equals assimilation, 4. The mean rate of respiratory CO{sub 2} evolution in strong light was found to be less than that in the dark. Internal re-photosynthesis of respiratory carbon may have been sufficient to account for this effect. 5. The assimilation of C{sup 14}O{sub 2} is about 17% slower than that of C{sup 12}O{sub 2}.
Date: July 20, 1950
Creator: Weigl, J.W.; Warrington, P.M. & Calvin, M.
Partner: UNT Libraries Government Documents Department

The Relation of Quantum Requirement in Photosynthesis toRespiration

Description: 1. The r a t e s of photosynthesis and subsequent respiration of Chlorella pyrenoidosa were measured using an oxygen analyzer (sensitive to paramagnetism). The energy absorbed during the photosynthesis periods was determined and the quantum requirement was calculated. 2. Dark respiration r a t e was found to depend on the r a t e of light absorption during the period of photosynthesis, and increased with increasing photosynthesis rate. 3 . The quantum requirement, corrected for respiration, varied from 4. 9 ( a t a ratio of photosynthesis to respiration of 1.4) to 6. 9 (at a r a t i o of 12). Both uncorrected and corrected quantum requirements approach an experimental value of 7. 4 a t high light intensity. 4. The lower quantum requirement obtained a t low light intensity is believed to be due to a relatively greater importance of contribution of energy from respiration t o photosynthesis. An expression i s derived for the relation between this contribution and the enhancement of dark respiration due to the level of photosynthesis to which the plants a r e conditioned. 5. Attempts to obtain the blue -light stimulation of photosynthesis with algae photosynthesizing in r e d light were unsuccessful.
Date: January 21, 1955
Creator: Bassham, James A.; Shibata, Kazuo & Calvin, M.
Partner: UNT Libraries Government Documents Department

The Relationship Between the Metabolic Pools of Photosynthetic andRespiratory Intermediates

Description: Using radioactive carbon dioxide, an attempt has been made to distinguish the various pools of intermediary metabolism which may be physically or chemically separate within the cell. Some correlation between the structural elements of the cells and these pools appears possible.
Date: July 1, 1958
Creator: Moses, V.; Calvin, M.; Holm-Hansen, O. & Bassham, J.A.
Partner: UNT Libraries Government Documents Department

Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers

Description: Rivers are generally supersaturated with respect to carbon dioxide, resulting in large gas evasion fluxes that can be a significant component of regional net carbon budgets. Amazonian rivers were recently shown to outgas more than ten times the amount of carbon exported to the ocean in the form of total organic carbon or dissolved inorganic carbon. High carbon dioxide concentrations in rivers originate largely from in situ respiration of organic carbon, but little agreement exists about the sources or turnover times of this carbon. Here we present results of an extensive survey of the carbon isotope composition ({sup 13}C and {sup 14}C) of dissolved inorganic carbon and three size-fractions of organic carbon across the Amazonian river system. We find that respiration of contemporary organic matter (less than 5 years old) originating on land and near rivers is the dominant source of excess carbon dioxide that drives outgassing in mid-size to large rivers, although we find that bulk organic carbon fractions transported by these rivers range from tens to thousands of years in age. We therefore suggest that a small, rapidly cycling pool of organic carbon is responsible for the large carbon fluxes from land to water to atmosphere in the humid tropics.
Date: June 23, 2005
Creator: Mayorga, E; Aufdenkampe, A K; Masiello, C A; Krusche, A V; Hedges, J I; Quay, P D et al.
Partner: UNT Libraries Government Documents Department

Surface CO2 leakage during the first shallow subsurface CO2release experiment

Description: A new field facility was used to study CO2 migrationprocesses and test techniques to detect and quantify potential CO2leakage from geologic storage sites. For 10 days starting 9 July 2007,and for seven days starting 5 August 2007, 0.1 and 0.3 t CO2 d-1,respectively, were released from a ~;100-m long, sub-water table (~;2.5-mdepth) horizontal well. The spatio-temporal evolution of leakage wasmapped through repeated grid measurements of soil CO2 flux (FCO2). Thesurface leakage onset, approach to steady state, and post-release declinematched model predictions closely. Modeling suggested that minimal CO2was taken up by groundwater through dissolution, and CO2 spread out ontop of the water table. FCO2 spatial patterns were related to well designand soil physical properties. Estimates of total CO2 discharge along withsoil respiration and leakage discharge highlight the influence ofbackground CO2 flux variations on detection of CO2 leakagesignals.
Date: September 15, 2007
Creator: Lewicki, J.L.; Oldenburg, C.; Dobeck, L. & Spangler, L.
Partner: UNT Libraries Government Documents Department