Science.gov

Sample records for adequate oxygen supply

  1. Oxygen supplies in disaster management.

    PubMed

    Blakeman, Thomas C; Branson, Richard D

    2013-01-01

    Mass casualty events and disasters, both natural and human-generated, occur frequently around the world and can generate scores of injured or ill victims in need of resources. Of the available medical supplies, oxygen remains the critical consumable resource in disaster management. Strategic management of oxygen supplies in disaster scenarios remains a priority. Hospitals have large supplies of liquid oxygen and a supply of compressed gas oxygen cylinders that allow several days of reserve, but a large influx of patients from a disaster can strain these resources. Most backup liquid oxygen supplies are attached to the main liquid system and supply line. In the event of damage to the main system, the reserve supply is rendered useless. The Strategic National Stockpile supplies medications, medical supplies, and equipment to disaster areas, but it does not supply oxygen. Contracted vendors can deliver oxygen to alternate care facilities in disaster areas, in the form of concentrators, compressed gas cylinders, and liquid oxygen. Planning for oxygen needs following a disaster still presents a substantial challenge, but alternate care facilities have proven to be valuable in relieving pressure from the mass influx of patients into hospitals, especially for those on home oxygen who require only an electrical source to power their oxygen concentrator.

  2. Influenza 2005-2006: vaccine supplies adequate, but bird flu looms.

    PubMed

    Mossad, Sherif B

    2005-11-01

    Influenza vaccine supplies appear to be adequate for the 2005-2006 season, though delivery has been somewhat delayed. However, in the event of a pandemic of avian flu-considered inevitable by most experts, although no one knows when it will happen-the United States would be woefully unprepared.

  3. Oil & gas in the 1990`s and beyond: Adequate supplies, growing demand, flat prices

    SciTech Connect

    Kennedy, J.L.

    1995-06-01

    Long term petroleum market fundamentals are clear: supplies are adequate and world demand will continue to grow steadily. Adequate supplies insure that prices will not increase significantly, on average, till the end of the 1990`s, probably much beyond. Despite plentiful supply and modest price increases, there will be peaks and valleys in the price graph as productive capacity is used up, then expanded. Tens of billions of dollars will be needed over the next decade to expand producing capacity. World oil consumption will increase at about 1.5% per year, at least for the next decade. Demand in Asia and Latin America will grow several times faster than this average world rate. World natural gas demand will grow at more then 2% per year well past 2000. Oil and gas companies around the world have changed the way they operate to survive the market realities of the 1990`s. restructuring, outsourcing, and partnering will continue as increasing costs and flat prices squeeze profits. Energy use patterns will change. Fuel and other product specifications will change. Market shares of oil and gas will shift. But opportunities abound in this new market environment. Growing markets always provide opportunities. Technology has helped operators dramatically lower finding, developing, and producing costs. The petroleum age is far from being over. Growing markets, adequate supply, affordable products, and a 60% market share. Those are the signs of an industry with a bright future.

  4. Chandra Reveals Rich Oxygen Supply

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This striking Chandra X-Ray Observatory image of supernova remnant SNR0103-72.6 reveals a nearly perfect ring about 150 light years in diameter surrounding a cloud of gas enriched in oxygen and shock-heated to millions of degrees Celsius. The ring marks the outer limits of a shock wave produced as material ejected in the supernova explosion collides with the interstellar gas. The size of the ring indicates that we see the supernova remnant as it was about 10,000 years after its progenitor star exploded. Located in the Small Magenellanic Cloud (SMC), SNR 0103-72.6 is about 190,000 light years from Earth. The x-rays take about 190,000 years to reach us from the SMC, so the supernova explosion occurred about 200,000 years ago, as measured on Earth. Scientists have know for years that oxygen and many other elements necessary for life are created in massive stars and dispersed in supernova explosions, but few remnants rich in these elements have been observed. This supernova remnant will hence become an important laboratory for studying how stars forge the elements necessary for life.

  5. Firefly light flashing: oxygen supply mechanism.

    PubMed

    Tsai, Yueh-Lin; Li, Chia-Wei; Hong, Tzay-Ming; Ho, Jen-Zon; Yang, En-Cheng; Wu, Wen-Yen; Margaritondo, G; Hsu, Su-Ting; Ong, Edwin B L; Hwu, Y

    2014-12-19

    Firefly luminescence is an intriguing phenomenon with potential technological applications, whose biochemistry background was only recently established. The physics side of this phenomenon, however, was still unclear, specifically as far as the oxygen supply mechanism for light flashing is concerned. This uncertainty is due to the complex microscopic structure of the tracheal system: without fully knowing its geometry, one cannot reliably test the proposed mechanisms. We solved this problem using synchrotron phase contrast microtomography and transmission x-ray microscopy, finding that the oxygen consumption corresponding to mitochondria functions exceeds the maximum rate of oxygen diffusion from the tracheal system to the photocytes. Furthermore, the flashing mechanism uses a large portion of this maximum rate. Thus, the flashing control requires passivation of the mitochondria functions, e.g., by nitric oxide, and switching of the oxygen supply from them to photoluminescence.

  6. Oxygen Supply from the Bird's Eye Perspective

    PubMed Central

    Blank, Miriam; Kiger, Laurent; Thielebein, Anke; Gerlach, Frank; Hankeln, Thomas; Marden, Michael C.; Burmester, Thorsten

    2011-01-01

    The visual process in the vertebrate eye requires high amounts of metabolic energy and thus oxygen. Oxygen supply of the avian retina is a challenging task because birds have large eyes, thick retinae, and high metabolic rates but neither deep retinal nor superficial capillaries. Respiratory proteins such as myoglobin may enhance oxygen supply to certain tissues, and thus the mammalian retina harbors high amounts of neuroglobin. Globin E (GbE) was recently identified as an eye-specific globin of chicken (Gallus gallus). Orthologous GbE genes were found in zebra finch and turkey genomes but appear to be absent in non-avian vertebrate classes. Analyses of globin phylogeny and gene synteny showed an ancient origin of GbE but did not help to assign it to any specific globin type. We show that the photoreceptor cells of the chicken retina have a high level of GbE protein, which accumulates to ∼10 μm in the total eye. Quantitative real-time RT-PCR revealed an ∼50,000-fold higher level of GbE mRNA in the eye than in the brain. Spectroscopic analysis and ligand binding kinetics of recombinant chicken GbE reveal a penta-coordinated globin with an oxygen affinity of P50 = 5.8 torrs at 25 °C and 15 torrs at 41 °C. Together these data suggest that GbE helps to sustain oxygen supply to the avian retina. PMID:21622558

  7. 14 CFR 23.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Oxygen equipment and supply. 23.1441... Miscellaneous Equipment § 23.1441 Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, or the airplane is approved for operations at or above altitudes where oxygen...

  8. 14 CFR 23.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oxygen equipment and supply. 23.1441... Miscellaneous Equipment § 23.1441 Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, or the airplane is approved for operations at or above altitudes where oxygen...

  9. 14 CFR 25.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the equipment must meet the requirements of this section and §§ 25.1443 through 25.1453. (b) The oxygen...

  10. 14 CFR 23.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Oxygen equipment and supply. 23.1441... Miscellaneous Equipment § 23.1441 Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, or the airplane is approved for operations at or above altitudes where oxygen...

  11. 14 CFR 25.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the equipment must meet the requirements of this section and §§ 25.1443 through 25.1453. (b) The oxygen...

  12. 14 CFR 23.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Oxygen equipment and supply. 23.1441... Miscellaneous Equipment § 23.1441 Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, or the airplane is approved for operations at or above altitudes where oxygen...

  13. 14 CFR 25.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the equipment must meet the requirements of this section and §§ 25.1443 through 25.1453. (b) The oxygen...

  14. 14 CFR 25.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the equipment must meet the requirements of this section and §§ 25.1443 through 25.1453. (b) The oxygen...

  15. 14 CFR 23.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Oxygen equipment and supply. 23.1441... Miscellaneous Equipment § 23.1441 Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, or the airplane is approved for operations at or above altitudes where oxygen...

  16. 14 CFR 25.1441 - Oxygen equipment and supply.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Oxygen equipment and supply. 25.1441... Oxygen equipment and supply. (a) If certification with supplemental oxygen equipment is requested, the equipment must meet the requirements of this section and §§ 25.1443 through 25.1453. (b) The oxygen...

  17. MRS evidence of adequate O2 supply in human skeletal muscle at the onset of exercise

    PubMed Central

    Richardson, Russell S.; Wary, Claire; Wray, D. Walter; Hoff, Jan; Rossiter, Harry; Layec, Gwenael; Carlier, Pierre G.

    2015-01-01

    Purpose At exercise onset, intramuscular oxidative energy production responds relatively slowly in comparison to the change in ATP demand. To determine if the slow kinetics of oxidative ATP production is due to inadequate O2 supply or metabolic inertia we studied the kinetics of intramyocellular deoxygenation (deoxy-myoglobin, Mb) and metabolism (phosphocreatine, PCr), using proton (1H) and phosphorus (31P) magnetic resonance spectroscopy (MRS) in 6 healthy subjects (33 ± 5 yrs). Methods Specifically, utilizing dynamic plantar flexion exercise, rest to exercise and recovery was assessed at both 60% of maximum work rate (WRmax) (moderate intensity) and 80% of WRmax (heavy intensity). Results At exercise onset [PCr] fell without delay and with a similar time constant (τ) at both exercise intensities (~33 s). In contrast, the increase in deoxy-Mb was delayed at exercise onset by 5–7 s, after which it increased with kinetics (moderate τ = 37 ± 9 s, and heavy τ = 29 ± 6 s) that were not different from τPCr (p > 0.05). At cessation, deoxy-Mb recovered without a time delay and more rapidly (τ ~20 s) than PCr (τ ~33 s) (p < 0.05). Conclusion using a unique combination of in vivo MRS techniques with high time-resolution, this study revealed a delay in intramuscular de-oxygenation at the onset of exercise, and rapid re-oxygenation kinetics upon cessation. Together these data imply that intramuscular substrate-enzyme interactions, and not O2 availability, determine the exercise onset kinetics of oxidative metabolism in healthy human skeletal muscle. PMID:25830362

  18. Switching off angiogenic signalling: creating channelled constructs for adequate oxygen delivery in tissue engineered constructs.

    PubMed

    Cheema, U; Alekseeva, T; Abou-Neel, E A; Brown, R A

    2010-10-06

    A major question in biomimetic tissue engineering is how much of the structure/function of native vasculature needs to be reproduced for effective tissue perfusion. O2 supplied to cells in 3D scaffolds in vitro is initially dependent upon diffusion through the scaffold and cell consumption. Low O2 (3%) enhances specific cell behaviours, but where O2 is critically low (pathological hypoxia) cell survival becomes compromised. We measured real-time O2 in 3D scaffolds and introduced micro-channelled architecture to controllably increase delivery of O2 to cells and switch off the hypoxic response. Simple static micro-channelling gives adequate perfusion and can be used to control cell generated hypoxia-induced signalling.

  19. "Oxygen supply" as modulator of aging processes: hypoxia and hyperoxia models for aging studies.

    PubMed

    Cataldi, Amelia; Di Giulio, Camillo

    2009-07-01

    Cell growth is regulated by several factors, including oxygen supply, which influence cell metabolism. Aging is characterized by decreased oxygen supply to tissue, a reduction of tissue PO(2) and of the activity of several enzymes and metabolic factors. The oxygen-gradient diffusion at capillary tissue level is essential for the cellular survival, while the homeostasis of the oxygen in the arterial blood is mediated by reflexes sensitive to oxygen decrease and by release of several factors. Aging is correlated with a reduction of cells' oxygen supply concomitant to a parallel decrease in oxygen demand by tissues. Both chronic hypoxia or hyperoxia are considered as stresses. Indeed, in both conditions, free radical species, which damage structural and functional components of the membrane, are generated. ROS (reactive oxygen species) are physiological products of aerobic life and their accumulation affects aging. Because hypoxia per se modulates mitochondria activity, influencing oxygen consumption, hypoxia and aging could share some link. Moreover, the observation that in hypoxia or hyperoxia there is an accumulation of lipofucsine as a general reaction to stress is consistent with the accumulation of such components during aging. Correlation between hypoxia-hyperoxia and life-span remains open until we solve the question of how and why do cells sense oxygen. In other words, to better understand aging we need to know what O(2) species are being sensed by cells. In conclusion, hypoxia and hyperoxia represent an experimental model adequate for studying aging processes.

  20. Metered oxygen supply aids treatment of domestic sewage

    NASA Technical Reports Server (NTRS)

    Weliky, N.; Hooper, T. J.; Silverman, H. P.

    1972-01-01

    Microbiological fixed-bed process was developed in which supplementary oxygen required by microbial species is supplied by electrochemical device. Rate of addition of oxygen to waste treatment process is controlled to maintain aerobic metabolism and prevent anaerobic metabolisms which produce odorous or toxic products.

  1. The development of a noncryogenic nitrogen/oxygen supply technique

    NASA Technical Reports Server (NTRS)

    Greenough, B. M.

    1971-01-01

    A development program was conducted in two phases to define the characteristics and requirements of an electrochemical oxygen/nitrogen supply technique for space station application. In Phase 1, electrode formulations and structures suitable for use as anodes in an oxygen/nitrogen generator were experimentally investigated. A one-man model oxygen/nitrogen generator integrated with a space cabin atmosphere simulator was fabricated and successfully tested in Phase 2. Data from these tests were used to update a computer routine model of the cabin atmosphere control using the oxygen/nitrogen generator technique. A specification and preliminary design for a 12-man oxygen/ nitrogen generation system was prepared.

  2. The oxycoal process with cryogenic oxygen supply

    NASA Astrophysics Data System (ADS)

    Kather, Alfons; Scheffknecht, Günter

    2009-09-01

    Due to its large reserves, coal is expected to continue to play an important role in the future. However, specific and absolute CO2 emissions are among the highest when burning coal for power generation. Therefore, the capture of CO2 from power plants may contribute significantly in reducing global CO2 emissions. This review deals with the oxyfuel process, where pure oxygen is used for burning coal, resulting in a flue gas with high CO2 concentrations. After further conditioning, the highly concentrated CO2 is compressed and transported in the liquid state to, for example, geological storages. The enormous oxygen demand is generated in an air-separation unit by a cryogenic process, which is the only available state-of-the-art technology. The generation of oxygen and the purification and liquefaction of the CO2-enriched flue gas consumes significant auxiliary power. Therefore, the overall net efficiency is expected to be lowered by 8 to 12 percentage points, corresponding to a 21 to 36% increase in fuel consumption. Oxygen combustion is associated with higher temperatures compared with conventional air combustion. Both the fuel properties as well as limitations of steam and metal temperatures of the various heat exchanger sections of the steam generator require a moderation of the temperatures during combustion and in the subsequent heat-transfer sections. This is done by means of flue gas recirculation. The interdependencies among fuel properties, the amount and the temperature of the recycled flue gas, and the resulting oxygen concentration in the combustion atmosphere are investigated. Expected effects of the modified flue gas composition in comparison with the air-fired case are studied theoretically and experimentally. The different atmosphere resulting from oxygen-fired combustion gives rise to various questions related to firing, in particular, with regard to the combustion mechanism, pollutant reduction, the risk of corrosion, and the properties of the fly

  3. The oxycoal process with cryogenic oxygen supply.

    PubMed

    Kather, Alfons; Scheffknecht, Günter

    2009-09-01

    Due to its large reserves, coal is expected to continue to play an important role in the future. However, specific and absolute CO2 emissions are among the highest when burning coal for power generation. Therefore, the capture of CO2 from power plants may contribute significantly in reducing global CO2 emissions. This review deals with the oxyfuel process, where pure oxygen is used for burning coal, resulting in a flue gas with high CO2 concentrations. After further conditioning, the highly concentrated CO2 is compressed and transported in the liquid state to, for example, geological storages. The enormous oxygen demand is generated in an air-separation unit by a cryogenic process, which is the only available state-of-the-art technology. The generation of oxygen and the purification and liquefaction of the CO2-enriched flue gas consumes significant auxiliary power. Therefore, the overall net efficiency is expected to be lowered by 8 to 12 percentage points, corresponding to a 21 to 36% increase in fuel consumption. Oxygen combustion is associated with higher temperatures compared with conventional air combustion. Both the fuel properties as well as limitations of steam and metal temperatures of the various heat exchanger sections of the steam generator require a moderation of the temperatures during combustion and in the subsequent heat-transfer sections. This is done by means of flue gas recirculation. The interdependencies among fuel properties, the amount and the temperature of the recycled flue gas, and the resulting oxygen concentration in the combustion atmosphere are investigated. Expected effects of the modified flue gas composition in comparison with the air-fired case are studied theoretically and experimentally. The different atmosphere resulting from oxygen-fired combustion gives rise to various questions related to firing, in particular, with regard to the combustion mechanism, pollutant reduction, the risk of corrosion, and the properties of the fly

  4. Placental Gas Exchange and the Oxygen Supply to the Fetus.

    PubMed

    Carter, Anthony M

    2015-07-01

    The oxygen supply of the fetus depends on the blood oxygen content and flow rate in the uterine and umbilical arteries and the diffusing capacity of the placenta. Oxygen consumption by the placenta is a significant factor and a potential limitation on availability to the fetus. The relevance of these several factors as well as responses to acute or sustained hypoxia has been explored in the sheep model. In addition, much has been learned in the context of hypobaric hypoxia by studying human populations that have resided at high altitude for varying periods of time. Embryonic development occurs under anaerobic conditions and even the fetus is adapted to a low oxygen environment. Nevertheless, there is a reserve capacity, and during acute hypoxia the fetus can counter a 50% reduction in oxygen delivery by increasing fractional extraction. During sustained hypoxia, on the other hand, fetal growth is slowed, although oxygen consumption is unaltered when corrected for fetal mass. Similarly, birth weight is reduced in humans living at high altitude even if the effect is tempered in those with a long highland ancestry. Placental mass changes little during sustained hypoxia in sheep or humans at high altitude. This conceals the fact that there are structural changes and that placental oxygen consumption is reduced. The underlying mechanisms are a current focus of research. One intriguing possibility is that increased anaerobic metabolism of glucose in the placenta spares oxygen for the fetus but reduces its supply of substrate and thereby limits fetal growth.

  5. Hypoxia inducible factor-2α regulates the development of retinal astrocytic network by maintaining adequate supply of astrocyte progenitors.

    PubMed

    Duan, Li-Juan; Takeda, Kotaro; Fong, Guo-Hua

    2014-01-01

    Here we investigate the role of hypoxia inducible factor (HIF)-2α in coordinating the development of retinal astrocytic and vascular networks. Three Cre mouse lines were used to disrupt floxed Hif-2α, including Rosa26(CreERT2), Tie2(Cre), and GFAP(Cre). Global Hif-2α disruption by Rosa26(CreERT2) led to reduced astrocytic and vascular development in neonatal retinas, whereas endothelial disruption by Tie2(Cre) had no apparent effects. Hif-2α deletion in astrocyte progenitors by GFAP(Cre) significantly interfered with the development of astrocytic networks, which failed to reach the retinal periphery and were incapable of supporting vascular development. Perplexingly, the abundance of strongly GFAP(+) mature astrocytes transiently increased at P0 before they began to lag behind the normal controls by P3. Pax2(+) and PDGFRα(+) astrocytic progenitors and immature astrocytes were dramatically diminished at all stages examined. Despite decreased number of astrocyte progenitors, their proliferation index or apoptosis was not altered. The above data can be reconciled by proposing that HIF-2α is required for maintaining the supply of astrocyte progenitors by slowing down their differentiation into non-proliferative mature astrocytes. HIF-2α deficiency in astrocyte progenitors may accelerate their differentiation into astrocytes, a change which greatly interferes with the replenishment of astrocyte progenitors due to insufficient time for proliferation. Rapidly declining progenitor supply may lead to premature cessation of astrocyte development. Given that HIF-2α protein undergoes oxygen dependent degradation, an interesting possibility is that retinal blood vessels may regulate astrocyte differentiation through their oxygen delivery function. While our findings support the consensus that retinal astrocytic template guides vascular development, they also raise the possibility that astrocytic and vascular networks may mutually regulate each other's development

  6. Large arteriolar component of oxygen delivery implies safe margin of oxygen supply to cerebral tissue

    PubMed Central

    Sakadžić, Sava; Mandeville, Emiri T.; Gagnon, Louis; Musacchia, Joseph J.; Yaseen, Mohammad A.; Yucel, Meryem A; Lefebvre, Joel; Lesage, Frédéric; Dale, Anders M.; Eikermann-Haerter, Katharina; Ayata, Cenk; Srinivasan, Vivek J.; Lo, Eng H.; Devor, Anna; Boas, David A.

    2014-01-01

    What is the organization of cerebral microvascular oxygenation and morphology that allows adequate tissue oxygenation at different activity levels? We address this question in the mouse cerebral cortex using microscopic imaging of intravascular O2 partial pressure and blood flow combined with numerical modeling. Here we show that parenchymal arterioles are responsible for 50% of the extracted O2 at baseline activity and the majority of the remaining O2 exchange takes place within the first few capillary branches. Most capillaries release little O2 at baseline acting as an O2 reserve that is recruited during increased neuronal activity or decreased blood flow. Our results challenge the common perception that capillaries are the major site of O2 delivery to cerebral tissue. The understanding of oxygenation distribution along arterio-capillary paths may have profound implications for the interpretation of BOLD fMRI signal and for evaluating microvascular O2 delivery capacity to support cerebral tissue in disease. PMID:25483924

  7. Large arteriolar component of oxygen delivery implies a safe margin of oxygen supply to cerebral tissue.

    PubMed

    Sakadžić, Sava; Mandeville, Emiri T; Gagnon, Louis; Musacchia, Joseph J; Yaseen, Mohammad A; Yucel, Meryem A; Lefebvre, Joel; Lesage, Frédéric; Dale, Anders M; Eikermann-Haerter, Katharina; Ayata, Cenk; Srinivasan, Vivek J; Lo, Eng H; Devor, Anna; Boas, David A

    2014-12-08

    What is the organization of cerebral microvascular oxygenation and morphology that allows adequate tissue oxygenation at different activity levels? We address this question in the mouse cerebral cortex using microscopic imaging of intravascular O2 partial pressure and blood flow combined with numerical modelling. Here we show that parenchymal arterioles are responsible for 50% of the extracted O2 at baseline activity, and the majority of the remaining O2 exchange takes place within the first few capillary branches. Most capillaries release little O2 at baseline acting as an O2 reserve that is recruited during increased neuronal activity or decreased blood flow. Our results challenge the common perception that capillaries are the major site of O2 delivery to cerebral tissue. The understanding of oxygenation distribution along arterio-capillary paths may have profound implications for the interpretation of blood-oxygen-level dependent (BOLD) contrast in functional magnetic resonance imaging and for evaluating microvascular O2 delivery capacity to support cerebral tissue in disease.

  8. Oxygen supply in aquatic ectotherms: partial pressure and solubility together explain biodiversity and size patterns.

    PubMed

    Verberk, Wilco C E P; Bilton, David T; Calosi, Piero; Spicer, John I

    2011-08-01

    Aquatic ectotherms face the continuous challenge of capturing sufficient oxygen from their environment as the diffusion rate of oxygen in water is 3 x 10(5) times lower than in air. Despite the recognized importance of oxygen in shaping aquatic communities, consensus on what drives environmental oxygen availability is lacking. Physiologists emphasize oxygen partial pressure, while ecologists emphasize oxygen solubility, traditionally expressing oxygen in terms of concentrations. To resolve the question of whether partial pressure or solubility limits oxygen supply in nature, we return to first principles and derive an index of oxygen supply from Fick's classic first law of diffusion. This oxygen supply index (OSI) incorporates both partial pressure and solubility. Our OSI successfully explains published patterns in body size and species across environmental clines linked to differences in oxygen partial pressure (altitude, organic pollution) or oxygen solubility (temperature and salinity). Moreover, the OSI was more accurately and consistently related to these ecological patterns than other measures of oxygen (oxygen saturation, dissolved oxygen concentration, biochemical oxygen demand concentrations) and similarly outperformed temperature and altitude, which covaried with these environmental clines. Intriguingly, by incorporating gas diffusion rates, it becomes clear that actually more oxygen is available to an organism in warmer habitats where lower oxygen concentrations would suggest the reverse. Under our model, the observed reductions in aerobic performance in warmer habitats do not arise from lower oxygen concentrations, but instead through organismal oxygen demand exceeding supply. This reappraisal of how organismal thermal physiology and oxygen demands together shape aerobic performance in aquatic ectotherms and the new insight of how these components change with temperature have broad implications for predicting the responses of aquatic communities to

  9. The Oxygen Supply and Demand Framework: a tool to support integrative learning.

    PubMed

    Shackell, Eileen; Gillespie, Mary

    2009-01-01

    Critically ill patients are at high risk for inadequate oxygen supply, increased oxygen demand and inadequate cellular oxygenation. Understanding and managing the physiological consequences of critical illness requires nurses to integrate knowledge of patient assessment, physiology and pathophysiology, and critical care interventions into their clinical decision-making. The Oxygen Supply and Demand Framework incorporates interrelated physiological concepts that influence balance between oxygen supply and demand and, consequently, supports an integrated understanding of critically ill patient situations. In this article, we present the Oxygen Supply and Demand Framework as an integrative tool for use by educators, students and critical care nurses to guide the process of patient assessment, interpret data, inform selection of appropriate interventions, and understand the rationale for all aspects of patient management.

  10. Theoretical analysis of oxygen supply to contracted skeletal muscle.

    PubMed

    Groebe, K; Thews, G

    1986-01-01

    Honig and collaborators reported striking contradictions in current understanding of O2 supply to working skeletal muscle. Therefore we re-examined the problem by means of a new composite computer simulation. As inclusion of erythrocytic O2 desaturation and oxygen transport and consumption inside the muscle cell into a single model would entail immense numerical difficulties, we broke up the whole process into its several components: O2 desaturation of erythrocytes O2 transport and consumption in muscle fiber capillary transit time characterizing the period of contact between red cell and muscle fiber. "Erythrocyte model" as well as "muscle fiber model" both consist of a central core cylinder surrounded by a concentric diffusion layer representing the extracellular resistance to O2 diffusion (Fig. 1). Resistance layers in both models are to be conceived of as one and the same anatomical structure--even though in each model their shape is adapted to the respective geometry. By means of this overlap region a spatial connexion between both is given, whereas temporal coherence governing O2 fluxes and red cell spacing is derived from capillary transit time. Analysis of individual components is outlined as follows: Assuming axial symmetry of the problem a numerical algorithm was employed to solve the parabolic system of partial differential equations describing red cell O2 desaturation. Hb-O2 reaction kinetics, free and facilitated O2 diffusion in axial and radial directions, and red cell movement in capillary were considered. Resulting time courses of desaturation, which are considerably faster than the ones computed by Honig et al., are given in the following table (see also Fig. 3). (Formula: see text) Furthermore, we studied the respective importance of the several processes included in our model: Omission of longitudinal diffusion increased desaturation time by 15% to 23%, whereas effects of reaction kinetics and axial movement were 5% and 2% respectively. For time

  11. Phytochelatin Synthesis Promotes Leaf Zn Accumulation of Arabidopsis thaliana Plants Grown in Soil with Adequate Zn Supply and is Essential for Survival on Zn-Contaminated Soil.

    PubMed

    Kühnlenz, Tanja; Hofmann, Christian; Uraguchi, Shimpei; Schmidt, Holger; Schempp, Stefanie; Weber, Michael; Lahner, Brett; Salt, David E; Clemens, Stephan

    2016-11-01

    Phytochelatin (PC) synthesis is essential for the detoxification of non-essential metals such as cadmium (Cd). In vitro experiments with Arabidopsis thaliana seedlings had indicated a contribution to zinc (Zn) tolerance as well. We addressed the physiological role of PC synthesis in Zn homeostasis of plants under more natural conditions. Growth responses, PC accumulation and leaf ionomes of wild-type and AtPCS1 mutant plants cultivated in different soils representing adequate Zn supply, Zn deficiency and Zn excess were analyzed. Growth on Zn-contaminated soil triggers PC synthesis and is strongly impaired in PC-deficient mutants. In fact, the contribution of AtPCS1 to tolerating Zn excess is comparable with that of the major Zn tolerance factor MTP1. For plants supplied with a normal level of Zn, a significant reduction in leaf Zn accumulation of AtPCS1 mutants was detected. In contrast, AtPCS1 mutants grown under Zn-limited conditions showed wild-type levels of Zn accumulation, suggesting the operation of distinct Zn translocation pathways. Contrasting phenotypes of the tested AtPCS1 mutant alleles upon growth in Zn- or Cd-contaminated soil indicated differential activation of PC synthesis by these metals. Experiments with truncated versions identified a part of the AtPCS1 protein required for the activation by Zn but not by Cd.

  12. Self-Monitoring Artificial Red Cells with Sufficient Oxygen Supply for Enhanced Photodynamic Therapy

    NASA Astrophysics Data System (ADS)

    Luo, Zhenyu; Zheng, Mingbin; Zhao, Pengfei; Chen, Ze; Siu, Fungming; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao

    2016-03-01

    Photodynamic therapy has been increasingly applied in clinical cancer treatments. However, native hypoxic tumoural microenvironment and lacking oxygen supply are the major barriers hindering photodynamic reactions. To solve this problem, we have developed biomimetic artificial red cells by loading complexes of oxygen-carrier (hemoglobin) and photosensitizer (indocyanine green) for boosted photodynamic strategy. Such nanosystem provides a coupling structure with stable self-oxygen supply and acting as an ideal fluorescent/photoacoustic imaging probe, dynamically monitoring the nanoparticle biodistribution and the treatment of PDT. Upon exposure to near-infrared laser, the remote-triggered photosensitizer generates massive cytotoxic reactive oxygen species (ROS) with sufficient oxygen supply. Importantly, hemoglobin is simultaneously oxidized into the more active and resident ferryl-hemoglobin leading to persistent cytotoxicity. ROS and ferryl-hemoglobin synergistically trigger the oxidative damage of xenograft tumour resulting in complete suppression. The artificial red cells with self-monitoring and boosted photodynamic efficacy could serve as a versatile theranostic platform.

  13. Study on Oxygen Supply Standard for Physical Health of Construction Personnel of High-Altitude Tunnels.

    PubMed

    Guo, Chun; Xu, Jianfeng; Wang, Mingnian; Yan, Tao; Yang, Lu; Sun, Zhitao

    2015-12-22

    The low atmospheric pressure and low oxygen content in high-altitude environment have great impacts on the functions of human body. Especially for the personnel engaged in complicated physical labor such as tunnel construction, high altitude can cause a series of adverse physiological reactions, which may result in multiple high-altitude diseases and even death in severe cases. Artificial oxygen supply is required to ensure health and safety of construction personnel in hypoxic environments. However, there are no provisions for oxygen supply standard for tunnel construction personnel in high-altitude areas in current tunnel construction specifications. As a result, this paper has theoretically studied the impacts of high-altitude environment on human bodies, analyzed the relationship between labor intensity and oxygen consumption in high-altitude areas and determined the critical oxygen-supply altitude values for tunnel construction based on two different standard evaluation systems, i.e., variation of air density and equivalent PIO₂. In addition, it has finally determined the oxygen supply standard for construction personnel in high-altitude areas based on the relationship between construction labor intensity and oxygen consumption.

  14. Study on Oxygen Supply Standard for Physical Health of Construction Personnel of High-Altitude Tunnels

    PubMed Central

    Guo, Chun; Xu, Jianfeng; Wang, Mingnian; Yan, Tao; Yang, Lu; Sun, Zhitao

    2015-01-01

    The low atmospheric pressure and low oxygen content in high-altitude environment have great impacts on the functions of human body. Especially for the personnel engaged in complicated physical labor such as tunnel construction, high altitude can cause a series of adverse physiological reactions, which may result in multiple high-altitude diseases and even death in severe cases. Artificial oxygen supply is required to ensure health and safety of construction personnel in hypoxic environments. However, there are no provisions for oxygen supply standard for tunnel construction personnel in high-altitude areas in current tunnel construction specifications. As a result, this paper has theoretically studied the impacts of high-altitude environment on human bodies, analyzed the relationship between labor intensity and oxygen consumption in high-altitude areas and determined the critical oxygen-supply altitude values for tunnel construction based on two different standard evaluation systems, i.e., variation of air density and equivalent PIO2. In addition, it has finally determined the oxygen supply standard for construction personnel in high-altitude areas based on the relationship between construction labor intensity and oxygen consumption. PMID:26703703

  15. Artificial carrier for oxygen supply in biological systems.

    PubMed

    Dey, E S; Norrlöw, O; Liu, Y

    2004-04-01

    Several poly (dimethylsiloxanes) (PDMS) copolymers of dimethylsiloxane (DMS) with ethylene or propylene oxide were tested as artificial carriers for the delivery of oxygen to biological systems. Copolymers with a DMS content of 33% or lower enhanced glucose oxidation by 200% in contrast to the 25% increase produced by the same concentration of perfluorodecalin. When 0.05% of the copolymer with 18% DMS was included in the growth media of Bacillus thuriginensis, the biomass (growth rate) increased 1.5-fold. With 0.1% of this copolymer, actinorhodin production by Streptomyces coelicolor A3 (2) occurred in half the normal time and with an increased yield. In conclusion, these PDMS copolymers are a good alternative to perfluorodecalin as oxygen carriers in biotechnological processes.

  16. Enhancement of acute ethanol hepatotoxicity under conditions of low oxygen supply and ischemia/reperfusion. The role of oxygen radicals.

    PubMed

    Younes, M; Wagner, H; Strubelt, O

    1989-10-15

    Using isolated hemoglobin-free perfused rat livers we studied the effect of low oxygen supply on ethanol hepatotoxicity in two models. In the first model resembling low blood supply, perfusion rate was lowered from 60 to 10 ml/min after a 30 min-equilibration phase and kept low for 60 min. As a consequence, oxygen consumption fell from 1.76 +/- 0.15 mumol/min/g to 0.51 +/- 0.02 mumol/min/g. In the second model, total ischemia was accomplished by interruption of the perfusion for 30 min and was followed by reperfusion at a perfusion rate of 60 ml/min for a further 30 min. In this model, oxygen consumption returned immediately to normal values upon reperfusion. In both models, low oxygen supply had no toxic effects of its own on livers from fed rats. While ethanol (3 g/l) given under normoxic conditions led to a moderate hepatotoxicity, its application in both models of partial as well as total ischemia and reperfusion resulted in a marked liver damage as evidenced by a strong release of sorbitol dehydrogenase, glutamate-pyruvate-transaminase, lactate dehydrogenase and glutathione, as well as by an increase in hepatic calcium content. Inhibition of ethanol metabolism by 4-methylpyrazol prevented liver damage in both models indicating that metabolism of ethanol is a prerequisite for its toxicity to occur. Also, hepatotoxicity was inhibited partially by catalase and superoxide dismutase and nearly totally by deferrioxamine and allopurinol. Thus, reactive oxygen species which are produced during ethanol metabolism as well as under conditions of low oxygen supply are mediators of hepatic damage in both models employed.

  17. Optimizations on supply and distribution of dissolved oxygen in constructed wetlands: A review.

    PubMed

    Liu, Huaqing; Hu, Zhen; Zhang, Jian; Ngo, Huu Hao; Guo, Wenshan; Liang, Shuang; Fan, Jinlin; Lu, Shaoyong; Wu, Haiming

    2016-08-01

    Dissolved oxygen (DO) is one of the most important factors that can influence pollutants removal in constructed wetlands (CWs). However, problems of insufficient oxygen supply and inappropriate oxygen distribution commonly exist in traditional CWs. Detailed analyses of DO supply and distribution characteristics in different types of CWs were introduced. It can be concluded that atmospheric reaeration (AR) served as the promising point on oxygen intensification. The paper summarized possible optimizations of DO in CWs to improve its decontamination performance. Process (tidal flow, drop aeration, artificial aeration, hybrid systems) and parameter (plant, substrate and operating) optimizations are particularly discussed in detail. Since economic and technical defects are still being cited in current studies, future prospects of oxygen research in CWs terminate this review.

  18. Extravehicular mobility unit subcritical liquid oxygen storage and supply system

    NASA Technical Reports Server (NTRS)

    Anderson, John; Martin, Timothy; Hodgson, ED

    1992-01-01

    The storage of life support oxygen in the Extravehicular Mobility Unit in the liquid state offers some advantages over the current method of storing the oxygen as a high pressure gas. Storage volume is reduced because of the increased density associated with liquid. The lower storage and operating pressures also reduce the potential for leakage or bursting of the storage tank. The potential for combustion resulting from adiabatic combustion of the gas within lines and components is substantially reduced. Design constraints on components are also relaxed due to the lower system pressures. A design study was performed to determine the requirements for a liquid storage system and prepare a conceptual design. The study involved four tasks. The first was to identify system operating requirements that influence or direct the design of the system. The second was to define candidate storage system concepts that could possibly satisfy the requirements. An evaluation and comparison of the candidate concepts was conducted in the third task. The fourth task was devoted to preparing a conceptual design of the recommended storage system and to evaluate concerns with integration of the concept into the EMU. The results are presented.

  19. Role of erythrocyte-released ATP in the regulation of microvascular oxygen supply in skeletal muscle.

    PubMed

    Ellsworth, M L; Ellis, C G; Sprague, R S

    2016-03-01

    In a 1914 book entitled The Respiratory Function of the Blood, Joseph Barcroft stated that 'the cell takes what it needs and leaves the rest'. He postulated that there must be both a 'call for oxygen' and a 'mechanism by which the call elicits a response...' In the past century, intensive investigation has provided significant insights into the haemodynamic and biophysical mechanisms involved in supplying oxygen to skeletal muscle. However, the identification of the mechanism by which tissue oxygen needs are sensed and the affector responsible for altering the upstream vasculature to enable the need to be appropriately met has been a challenge. In 1995, Ellsworth et al. proposed that the oxygen-carrying erythrocyte, by virtue of its capacity to release the vasoactive mediator ATP in response to a decrease in oxygen saturation, could serve both roles. Several in vitro and in situ studies have established that exposure of erythrocytes to reduced oxygen tension induces the release of ATP which does result in a conducted arteriolar vasodilation with a sufficiently rapid time course to make the mechanism physiologically relevant. The components of the signalling pathway for the controlled release of ATP from erythrocytes in response to exposure to low oxygen tension have been determined. In addition, the implications of defective ATP release on human pathological conditions have been explored. This review provides a perspective on oxygen supply and the role that such a mechanism plays in meeting the oxygen needs of skeletal muscle.

  20. Improvement of islet function in a bioartificial pancreas by enhanced oxygen supply and growth hormone releasing hormone agonist

    PubMed Central

    Ludwig, Barbara; Rotem, Avi; Schmid, Janine; Weir, Gordon C.; Colton, Clark K.; Brendel, Mathias D.; Neufeld, Tova; Block, Norman L.; Yavriyants, Karina; Steffen, Anja; Ludwig, Stefan; Chavakis, Triantafyllos; Reichel, Andreas; Azarov, Dimitri; Zimermann, Baruch; Maimon, Shiri; Balyura, Mariya; Rozenshtein, Tania; Shabtay, Noa; Vardi, Pnina; Bloch, Konstantin; de Vos, Paul; Schally, Andrew V.; Bornstein, Stefan R.; Barkai, Uriel

    2012-01-01

    Islet transplantation is a feasible therapeutic alternative for metabolically labile patients with type 1 diabetes. The primary therapeutic target is stable glycemic control and prevention of complications associated with diabetes by reconstitution of endogenous insulin secretion. However, critical shortage of donor organs, gradual loss in graft function over time, and chronic need for immunosuppression limit the indication for islet transplantation to a small group of patients. Here we present a promising approach to address these limitations by utilization of a macrochamber specially engineered for islet transplantation. The s.c. implantable device allows for controlled and adequate oxygen supply and provides immunological protection of donor islets against the host immune system. The minimally invasive implantable chamber normalized blood glucose in streptozotocin-induced diabetic rodents for up to 3 mo. Sufficient graft function depended on oxygen supply. Pretreatment with the growth hormone-releasing hormone (GHRH) agonist, JI-36, significantly enhanced graft function by improving glucose tolerance and increasing β-cell insulin reserve in rats thereby allowing for a reduction of the islet mass required for metabolic control. As a result of hypervascularization of the tissue surrounding the device, no relevant delay in insulin response to glucose changes has been observed. Consequently, this system opens up a fundamental strategy for therapy of diabetes and may provide a promising avenue for future approaches to xenotransplantation. PMID:22393012

  1. Experimental manipulations of tissue oxygen supply do not affect warming tolerance of European perch.

    PubMed

    Brijs, Jeroen; Jutfelt, Fredrik; Clark, Timothy D; Gräns, Albin; Ekström, Andreas; Sandblom, Erik

    2015-08-01

    A progressive inability of the cardiorespiratory system to maintain systemic oxygen supply at elevated temperatures has been suggested to reduce aerobic scope and the upper thermal limit of aquatic ectotherms. However, few studies have directly investigated the dependence of thermal limits on oxygen transport capacity. By manipulating oxygen availability (via environmental hyperoxia) and blood oxygen carrying capacity (via experimentally induced anaemia) in European perch (Perca fluviatilis Linneaus), we investigated the effects of oxygen transport capacity on aerobic scope and the critical thermal maximum (CT(max)). Hyperoxia resulted in a twofold increase in aerobic scope at the control temperature of 23°C, but this did not translate to an elevated CT(max) in comparison with control fish (34.6±0.1 versus 34.0±0.5°C, respectively). Anaemia (∼43% reduction in haemoglobin concentration) did not cause a reduction in aerobic scope or CT(max) (33.8±0.3°C) compared with control fish. Additionally, oxygen consumption rates of anaemic perch during thermal ramping increased in a similar exponential manner to that in control fish, highlighting that perch have an impressive capacity to compensate for a substantial reduction in blood oxygen carrying capacity. Taken together, these results indicate that oxygen limitation is not a universal mechanism determining the CT(max) of fishes.

  2. Two-photon NADH imaging exposes boundaries of oxygen diffusion in cortical vascular supply regions

    PubMed Central

    Kasischke, Karl A; Lambert, Elton M; Panepento, Ben; Sun, Anita; Gelbard, Harris A; Burgess, Robert W; Foster, Thomas H; Nedergaard, Maiken

    2011-01-01

    Oxygen transport imposes a possible constraint on the brain's ability to sustain variable metabolic demands, but oxygen diffusion in the cerebral cortex has not yet been observed directly. We show that concurrent two-photon fluorescence imaging of endogenous nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation exposes well-defined boundaries of tissue oxygen diffusion in the mouse cortex. The NADH fluorescence increases rapidly over a narrow, very low pO2 range with a p50 of 3.4±0.6 mm Hg, thereby establishing a nearly binary reporter of significant, metabolically limiting hypoxia. The transient cortical tissue boundaries of NADH fluorescence exhibit remarkably delineated geometrical patterns, which define the limits of tissue oxygen diffusion from the cortical microcirculation and bear a striking resemblance to the ideal Krogh tissue cylinder. The visualization of microvessels and their regional contribution to oxygen delivery establishes penetrating arterioles as major oxygen sources in addition to the capillary network and confirms the existence of cortical oxygen fields with steep microregional oxygen gradients. Thus, two-photon NADH imaging can be applied to expose vascular supply regions and to localize functionally relevant microregional cortical hypoxia with micrometer spatial resolution. PMID:20859293

  3. Two-photon NADH imaging exposes boundaries of oxygen diffusion in cortical vascular supply regions.

    PubMed

    Kasischke, Karl A; Lambert, Elton M; Panepento, Ben; Sun, Anita; Gelbard, Harris A; Burgess, Robert W; Foster, Thomas H; Nedergaard, Maiken

    2011-01-01

    Oxygen transport imposes a possible constraint on the brain's ability to sustain variable metabolic demands, but oxygen diffusion in the cerebral cortex has not yet been observed directly. We show that concurrent two-photon fluorescence imaging of endogenous nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation exposes well-defined boundaries of tissue oxygen diffusion in the mouse cortex. The NADH fluorescence increases rapidly over a narrow, very low pO(2) range with a p(50) of 3.4 ± 0.6 mm Hg, thereby establishing a nearly binary reporter of significant, metabolically limiting hypoxia. The transient cortical tissue boundaries of NADH fluorescence exhibit remarkably delineated geometrical patterns, which define the limits of tissue oxygen diffusion from the cortical microcirculation and bear a striking resemblance to the ideal Krogh tissue cylinder. The visualization of microvessels and their regional contribution to oxygen delivery establishes penetrating arterioles as major oxygen sources in addition to the capillary network and confirms the existence of cortical oxygen fields with steep microregional oxygen gradients. Thus, two-photon NADH imaging can be applied to expose vascular supply regions and to localize functionally relevant microregional cortical hypoxia with micrometer spatial resolution.

  4. Dynamics of oxygen supply and consumption during mainstream large-scale composting in China.

    PubMed

    Zeng, Jianfei; Shen, Xiuli; Han, Lujia; Huang, Guangqun

    2016-11-01

    This study characterized some physicochemical and biological parameters to systematically evaluate the dynamics of oxygen supply and consumption during large-scale trough composting in China. The results showed that long active phases, low maximum temperatures, low organic matter losses and high pore methane concentrations were observed in different composting layers. Pore oxygen concentrations in the top, middle and bottom layers maintained <5vol.% for 40, 42 and 45days, respectively, which accounted for more than 89% of the whole period. After each mechanical turning, oxygen was consumed at a stable respiration rate to a concentration of 5vol.% in no more than 99min and remained anaerobic in the subsequent static condition. The daily percentage of time under aerobic condition was no more than 14% of a single day. Therefore, improving FAS, adjusting aeration interval or combining turning with forced aeration was suggested to provide sufficient oxygen during composting.

  5. Some like it hot: Thermal tolerance and oxygen supply capacity in two eurythermal crustaceans.

    PubMed

    Ern, Rasmus; Huong, Do Thi Thanh; Phuong, Nguyen Thanh; Madsen, Peter Teglberg; Wang, Tobias; Bayley, Mark

    2015-06-01

    Thermal sensitivity of the cardiorespiratory oxygen supply capacity has been proposed as the cardinal link underlying the upper boundary of the temperature niche in aquatic ectotherms. Here we examined the evidence for this link in two eurythermal decapods, the Giant tiger shrimp (Penaeus monodon) and the European crayfish (Astacus astacus). We found that both species have a temperature resistant cardiorespiratory system, capable of maintaining oxygen delivery up to their upper critical temperature (Tcrit). In neither species was Tcrit reduced in hypoxia (60% air saturation) and both species showed an exponential increase in heart and gill ventilation rates up to their Tcrit. Further, failure of action potential conduction in preparations of A. astacus motor neurons coincided with Tcrit, indicating that compromised nervous function may provide the underlying determinant for Tcrit rather than oxygen delivery. At high temperatures, absolute aerobic scope was maintained in P. monodon, but reduced in A. astacus. However, A. astacus also displayed reduced exercise intensity indicating that impaired muscle performance with resulting reduced tissue oxygen demand may explain the reduced scope rather than insufficient oxygen supply capacity. This interpretation agrees with early literature on aquatic ectotherms, correlating loss of nervous function with impaired locomotion as temperatures approach Tcrit.

  6. Some like it hot: Thermal tolerance and oxygen supply capacity in two eurythermal crustaceans

    PubMed Central

    Ern, Rasmus; Huong, Do Thi Thanh; Phuong, Nguyen Thanh; Madsen, Peter Teglberg; Wang, Tobias; Bayley, Mark

    2015-01-01

    Thermal sensitivity of the cardiorespiratory oxygen supply capacity has been proposed as the cardinal link underlying the upper boundary of the temperature niche in aquatic ectotherms. Here we examined the evidence for this link in two eurythermal decapods, the Giant tiger shrimp (Penaeus monodon) and the European crayfish (Astacus astacus). We found that both species have a temperature resistant cardiorespiratory system, capable of maintaining oxygen delivery up to their upper critical temperature (Tcrit). In neither species was Tcrit reduced in hypoxia (60% air saturation) and both species showed an exponential increase in heart and gill ventilation rates up to their Tcrit. Further, failure of action potential conduction in preparations of A. astacus motor neurons coincided with Tcrit, indicating that compromised nervous function may provide the underlying determinant for Tcrit rather than oxygen delivery. At high temperatures, absolute aerobic scope was maintained in P. monodon, but reduced in A. astacus. However, A. astacus also displayed reduced exercise intensity indicating that impaired muscle performance with resulting reduced tissue oxygen demand may explain the reduced scope rather than insufficient oxygen supply capacity. This interpretation agrees with early literature on aquatic ectotherms, correlating loss of nervous function with impaired locomotion as temperatures approach Tcrit. PMID:26030412

  7. The emerging role of AMPK in the regulation of breathing and oxygen supply

    PubMed Central

    Evans, A. Mark; Mahmoud, Amira D.; Moral-Sanz, Javier; Hartmann, Sandy

    2016-01-01

    Regulation of breathing is critical to our capacity to accommodate deficits in oxygen availability and demand during, for example, sleep and ascent to altitude. It is generally accepted that a fall in arterial oxygen increases afferent discharge from the carotid bodies to the brainstem and thus delivers increased ventilatory drive, which restores oxygen supply and protects against hypoventilation and apnoea. However, the precise molecular mechanisms involved remain unclear. We recently identified as critical to this process the AMP-activated protein kinase (AMPK), which is key to the cell-autonomous regulation of metabolic homoeostasis. This observation is significant for many reasons, not least because recent studies suggest that the gene for the AMPK-α1 catalytic subunit has been subjected to natural selection in high-altitude populations. It would appear, therefore, that evolutionary pressures have led to AMPK being utilized to regulate oxygen delivery and thus energy supply to the body in the short, medium and longer term. Contrary to current consensus, however, our findings suggest that AMPK regulates ventilation at the level of the caudal brainstem, even when afferent input responses from the carotid body are normal. We therefore hypothesize that AMPK integrates local hypoxic stress at defined loci within the brainstem respiratory network with an index of peripheral hypoxic status, namely afferent chemosensory inputs. Allied to this, AMPK is critical to the control of hypoxic pulmonary vasoconstriction and thus ventilation–perfusion matching at the lungs and may also determine oxygen supply to the foetus by, for example, modulating utero-placental blood flow. PMID:27574022

  8. Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells

    PubMed Central

    Mairbäurl, Heimo

    2013-01-01

    During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called “sports anemia.” This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise. PMID:24273518

  9. NEMS International Energy Module, model documentation report: World Oil Market, Petroleum Products Supply and Oxygenates Supply components

    SciTech Connect

    Not Available

    1994-04-04

    The Energy Information Administration (EIA) is developing the National Energy Modeling System (NEMS) to enhance its energy forecasting capabilities and to provide the Department of Energy with a comprehensive framework for analyzing alternative energy` futures. NEMS is designed with a multi-level modular structure that represents specific energy supply activities, conversion processes, and demand sectors as a series of self-contained units which are linked by an integrating mechanism. The NEMS International Energy Module (IEM) computes world oil prices and the resulting patterns of international trade in crude oil and refined products. This report is a reference document for energy analysts, model users, and the public that is intended to meet EIA`s legal obligation to provide adequate documentation for all statistical and forecast reports (Public Law 93-275, section 57(b)(1). Its purpose is to describe the structure of the IEM. Actual operation of the model is not discussed here. The report contains four sections summarizing the overall structure of the IEM and its interface with other NEMS modules, mathematical specifications of behavioral relationships, and data sources and estimation methods. Following a general description of the function and rationale of its key components, system and equation level information sufficient to permit independent evaluation of the model`s technical details is presented.

  10. EFFECTS OF RAPAMYCIN ON CEREBRAL OXYGEN SUPPLY AND CONSUMPTION DURING REPERFUSION AFTER CEREBRAL ISCHEMIA

    PubMed Central

    CHI, O. Z.; BARSOUM, S.; VEGA-COTTO, N. M.; JACINTO, E.; LIU, X.; MELLENDER, S. J.; WEISS, H. R.

    2016-01-01

    Abstract—Activation of the mammalian target of rapamycin (mTOR) leads to cell growth and survival. We tested the hypothesis that inhibition of mTOR would increase infarct size and decrease microregional O2 supply/consumption balance after cerebral ischemia–reperfusion. This was tested in isoflurane-anesthetized rats with middle cerebral artery blockade for 1 h and reperfusion for 2 h with and without rapamycin (20 mg/kg once daily for two days prior to ischemia). Regional cerebral blood flow was determined using a C14-iodoantipyrine autoradiographic technique. Regional small-vessel arterial and venous oxygen saturations were determined microspectrophotometrically. The control ischemic-reperfused cortex had a similar blood flow and O2 consumption to the contralateral cortex. However, microregional O2 supply/consumption balance was significantly reduced in the ischemic-reperfused cortex. Rapamycin significantly increased cerebral O2 consumption and further reduced O2 supply/consumption balance in the reperfused area. This was associated with an increased cortical infarct size (13.5 ± 0.8% control vs. 21.5 ± 0.9% rapamycin). We also found that ischemia–reperfusion increased AKT and S6K1 phosphorylation, while rapamycin decreased this phosphorylation in both the control and ischemic-reperfused cortex. This suggests that mTOR is important for not only cell survival, but also for the control of oxygen balance after cerebral ischemia–reperfusion. PMID:26742793

  11. Effects of rapamycin on cerebral oxygen supply and consumption during reperfusion after cerebral ischemia.

    PubMed

    Chi, O Z; Barsoum, S; Vega-Cotto, N M; Jacinto, E; Liu, X; Mellender, S J; Weiss, H R

    2016-03-01

    Activation of the mammalian target of rapamycin (mTOR) leads to cell growth and survival. We tested the hypothesis that inhibition of mTOR would increase infarct size and decrease microregional O2 supply/consumption balance after cerebral ischemia-reperfusion. This was tested in isoflurane-anesthetized rats with middle cerebral artery blockade for 1h and reperfusion for 2h with and without rapamycin (20mg/kg once daily for two days prior to ischemia). Regional cerebral blood flow was determined using a C(14)-iodoantipyrine autoradiographic technique. Regional small-vessel arterial and venous oxygen saturations were determined microspectrophotometrically. The control ischemic-reperfused cortex had a similar blood flow and O2 consumption to the contralateral cortex. However, microregional O2 supply/consumption balance was significantly reduced in the ischemic-reperfused cortex. Rapamycin significantly increased cerebral O2 consumption and further reduced O2 supply/consumption balance in the reperfused area. This was associated with an increased cortical infarct size (13.5±0.8% control vs. 21.5±0.9% rapamycin). We also found that ischemia-reperfusion increased AKT and S6K1 phosphorylation, while rapamycin decreased this phosphorylation in both the control and ischemic-reperfused cortex. This suggests that mTOR is important for not only cell survival, but also for the control of oxygen balance after cerebral ischemia-reperfusion.

  12. Is venous blood drawn from femoral access adequate to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients?

    PubMed Central

    Marti, Yara Nishiyama; de Freitas, Flávio Geraldo Rezende; de Azevedo, Rodrigo Palácio; Leão, Milena; Bafi, Antônio Tonete; Machado, Flavia Ribeiro

    2015-01-01

    Objectives The purpose of this study was to test if venous blood drawn from femoral access can be used to estimate the central venous oxygen saturation and arterial lactate levels in critically ill patients. Methods Bland-Altman analysis and Spearman correlations were used to compare the femoral venous oxygen saturation and central venous oxygen saturation as well as arterial lactate levels and femoral lactate. A pre-specified subgroup analysis was conducted in patients with signs of hypoperfusion. In addition, the clinical agreement was also investigated. Results Blood samples were obtained in 26 patients. In 107 paired samples, there was a moderate correlation (r = 0.686, p < 0.0001) between the central venous oxygen saturation and femoral venous oxygen saturation with a bias of 8.24 ± 10.44 (95% limits of agreement: -12.23 to 28.70). In 102 paired samples, there was a strong correlation between the arterial lactate levels and femoral lactate levels (r = 0.972, p < 0.001) with a bias of -2.71 ± 9.86 (95% limits of agreement: -22.03 to 16.61). The presence of hypoperfusion did not significantly change these results. The clinical agreement for venous saturation was inadequate, with different therapeutic decisions in 22.4% of the situation; for lactate, this was the case only in 5.2% of the situations. Conclusion Femoral venous oxygen saturation should not be used as a surrogate of central venous oxygen saturation. However, femoral lactate levels can be used in clinical practice, albeit with caution. PMID:26761471

  13. Enhancement of pyruvate production by Torulopsis glabrata using a two-stage oxygen supply control strategy.

    PubMed

    Li, Y; Hugenholtz, J; Chen, J; Lun, S-Y

    2002-10-01

    The effect of agitation speeds on the performance of producing pyruvate by a multi-vitamin auxotrophic yeast, Torulopsis glabrata, was investigated in batch fermentation. High pyruvate yield on glucose (0.797 g g(-1)) was achieved under high agitation speed (700 rpm), but the glucose consumption rate was rather low (1.14 g l(-1) h(-1)). Glucose consumption was enhanced under low agitation speed (500 rpm), but the pyruvate yield on glucose decreased to 0.483 g g(-1). Glycerol production was observed under low agitation speed and decreased with increasing agitation speed. Based on process analysis and carbon flux distribution calculation, a two-stage oxygen supply control strategy was proposed, in which the agitation speed was controlled at 700 rpm in the first 16 h and then switched to 500 rpm. This was experimentally proven to be successful. Relatively high concentration of pyruvate (69.4 g l(-1)), high pyruvate yield on glucose (0.636 g g(-1)), and high glucose consumption rate (1.95 g l(-1)h(-1)) were achieved by applying this strategy. The productivity (1.24 g l(-1) h(-1)) was improved by 36%, 23% and 31%, respectively, compared with fermentations in which agitation speeds were kept constant at 700 rpm, 600 rpm, and 500 rpm. Experimental results indicate that the difference between the performances for producing pyruvate under a favorable state of oxygen supply (dissolved oxygen concentration >50%) was caused by the different regeneration pathways of NADH generated from glycolysis.

  14. Coastal upwelling supplies oxygen-depleted water to the Columbia River estuary.

    PubMed

    Roegner, G Curtis; Needoba, Joseph A; Baptista, António M

    2011-04-20

    Low dissolved oxygen (DO) is a common feature of many estuarine and shallow-water environments, and is often attributed to anthropogenic nutrient enrichment from terrestrial-fluvial pathways. However, recent events in the U.S. Pacific Northwest have highlighted that wind-forced upwelling can cause naturally occurring low DO water to move onto the continental shelf, leading to mortalities of benthic fish and invertebrates. Coastal estuaries in the Pacific Northwest are strongly linked to ocean forcings, and here we report observations on the spatial and temporal patterns of oxygen concentration in the Columbia River estuary. Hydrographic measurements were made from transect (spatial survey) or anchor station (temporal survey) deployments over a variety of wind stresses and tidal states during the upwelling seasons of 2006 through 2008. During this period, biologically stressful levels of dissolved oxygen were observed to enter the Columbia River estuary from oceanic sources, with minimum values close to the hypoxic threshold of 2.0 mg L(-1). Riverine water was consistently normoxic. Upwelling wind stress controlled the timing and magnitude of low DO events, while tidal-modulated estuarine circulation patterns influenced the spatial extent and duration of exposure to low DO water. Strong upwelling during neap tides produced the largest impact on the estuary. The observed oxygen concentrations likely had deleterious behavioral and physiological consequences for migrating juvenile salmon and benthic crabs. Based on a wind-forced supply mechanism, low DO events are probably common to the Columbia River and other regional estuaries and if conditions on the shelf deteriorate further, as observations and models predict, Pacific Northwest estuarine habitats could experience a decrease in environmental quality.

  15. Effect of oxygen supply on Monascus pigments and citrinin production in submerged fermentation.

    PubMed

    Yang, Jian; Chen, Qi; Wang, Weiping; Hu, Jiajun; Hu, Chuan

    2015-05-01

    The influence of oxygen supply on Monascus pigments and citrinin production by Monascus ruber HS.4000 in submerged fermentation was studied. For Monascus cultivation with high pigments and low citrinin production, the initial growth phase, mid-stage phase, and later-stage production phase were separated by shifting oxygen supply. The optimal condition for the fermentation process in shake-flask fermentation was a three-stage rotating rate controlled strategy (0-48 h at 150 rpm, 48-108 h at 250 rpm, 108-120 h at 200 rpm) with medium volume of 100 mL added to 250 mL Erlenmeyer flasks at 30°C for 120 h cultivation. Compared to constant one-stage cultivation (medium volume of 100 mL, rotating rate of 250 rpm), the pigments were reduced by 40.4%, but citrinin was reduced by 64.2%. The most appropriate condition for the fermentation process in a 10 L fermentor is also a three-stage aeration process (0-48 h at 300 L/h, 48-96 h at 500 L/h, 96-120 h at 200 L/h) with agitation of 300 rpm at 30°C for 120 h cultivation, and 237.3 ± 5.7 U/mL pigments were produced in 120 h with 6.05 ± 0.19 mg/L citrinin in a 10 L fermentor. Compared to aeration-constant (500 L/h) cultivation, pigment production was increased by 29.6% and citrinin concentration was reduced by 79.5%.

  16. The Effect of Oxygen Supply on the Dual Growth Kinetics of Acidithiobacillus thiooxidans under Acidic Conditions for Biogas Desulfurization

    PubMed Central

    Namgung, Hyeong-Kyu; Song, JiHyeon

    2015-01-01

    In this study, to simulate a biogas desulfurization process, a modified Monod-Gompertz kinetic model incorporating a dissolved oxygen (DO) effect was proposed for a sulfur-oxidizing bacterial (SOB) strain, Acidithiobacillus thiooxidans, under extremely acidic conditions of pH 2. The kinetic model was calibrated and validated using experimental data obtained from a bubble-column bioreactor. The SOB strain was effective for H2S degradation, but the H2S removal efficiency dropped rapidly at DO concentrations less than 2.0 mg/L. A low H2S loading was effectively treated with oxygen supplied in a range of 2%–6%, but a H2S guideline of 10 ppm could not be met, even with an oxygen supply greater than 6%, when the H2S loading was high at a short gas retention time of 1 min and a H2S inlet concentration of 5000 ppm. The oxygen supply should be increased in the aerobic desulfurization to meet the H2S guideline; however, the excess oxygen above the optimum was not effective because of the decline in oxygen efficiency. The model estimation indicated that the maximum H2S removal rate was approximately 400 ppm/%-O2 at the influent oxygen concentration of 4.9% under the given condition. The kinetic model with a low DO threshold for the interacting substrates was a useful tool to simulate the effect of the oxygen supply on the H2S removal and to determine the optimal oxygen concentration. PMID:25633028

  17. Maintaining network activity in submerged hippocampal slices: importance of oxygen supply.

    PubMed

    Hájos, Norbert; Ellender, Tommas J; Zemankovics, Rita; Mann, Edward O; Exley, Richard; Cragg, Stephanie J; Freund, Tamás F; Paulsen, Ole

    2009-01-01

    Studies in brain slices have provided a wealth of data on the basic features of neurons and synapses. In the intact brain, these properties may be strongly influenced by ongoing network activity. Although physiologically realistic patterns of network activity have been successfully induced in brain slices maintained in interface-type recording chambers, they have been harder to obtain in submerged-type chambers, which offer significant experimental advantages, including fast exchange of pharmacological agents, visually guided patch-clamp recordings, and imaging techniques. Here, we investigated conditions for the emergence of network oscillations in submerged slices prepared from the hippocampus of rats and mice. We found that the local oxygen level is critical for generation and propagation of both spontaneously occurring sharp wave-ripple oscillations and cholinergically induced fast oscillations. We suggest three ways to improve the oxygen supply to slices under submerged conditions: (i) optimizing chamber design for laminar flow of superfusion fluid; (ii) increasing the flow rate of superfusion fluid; and (iii) superfusing both surfaces of the slice. These improvements to the recording conditions enable detailed studies of neurons under more realistic conditions of network activity, which are essential for a better understanding of neuronal network operation.

  18. Oxygen Levels in Thermoplastic Microfluidic Devices during Cell Culture

    PubMed Central

    Ochs, Christopher J.; Kasuya, Junichi; Pavesi, Andrea; Kamm, Roger D.

    2015-01-01

    We developed a computational model to predict oxygen levels in microfluidic plastic devices during cell culture. This model is based on experimental evaluation of oxygen levels. Conditions are determined that provide adequate oxygen supply to two cell types, hepatocytes and endothelial cells, either by diffusion through the plastic device, or by supplying a low flow rate of medium. PMID:24302467

  19. Oxygen levels in thermoplastic microfluidic devices during cell culture.

    PubMed

    Ochs, Christopher J; Kasuya, Junichi; Pavesi, Andrea; Kamm, Roger D

    2014-02-07

    We developed a computational model to predict oxygen levels in microfluidic plastic devices during cell culture. This model is based on experimental evaluation of oxygen levels. Conditions are determined that provide adequate oxygen supply to two cell types, hepatocytes and endothelial cells, either by diffusion through the plastic device, or by supplying a low flow rate of medium.

  20. Implementation and 8-year follow-up of an uninterrupted oxygen supply system in a hospital in The Gambia

    PubMed Central

    Light, J. D.; Ebonyi, A. O.; N'Jai, P. C.; Ideh, R. C.; Ebruke, B. E.; Nyassi, E.; Peel, D.

    2016-01-01

    SUMMARY SETTING: A 42-bed hospital operated by the Medical Research Council (MRC) Unit in The Gambia. OBJECTIVE: To devise, test and evaluate a cost-efficient uninterrupted oxygen system in the MRC Hospital. DESIGN: Oxygen cylinders were replaced with oxygen concentrators as the primary source of oxygen. An uninterruptable power supply (UPS) ensured continuity of power. Hospital staff were trained on the use of the new system. Eight years post-installation, an analysis of concentrator maintenance needs and costs was conducted and user feedback obtained to assess the success of the system. RESULTS: The new system saved at least 51% of oxygen supply costs compared to cylinders, with savings likely to have been far greater due to cylinder leakages. Users indicated that the system is easier to use and more reliable, although technical support and staff training are still needed. CONCLUSION: Oxygen concentrators offer long-term cost savings and an improved user experience compared to cylinders; however, some technical support and maintenance are needed to upkeep the system. A UPS dedicated to oxygen concentrators is an appropriate solution for settings where power interruptions are frequent but short in duration. This approach can be a model for health systems in settings with similar infrastructure. PMID:27393551

  1. Oxygen supply for CHO cells immobilized on a packed-bed of Fibra-Cel disks.

    PubMed

    Meuwly, F; Loviat, F; Ruffieux, P-A; Bernard, A R; Kadouri, A; von Stockar, U

    2006-03-05

    Packed-bed bioreactors (PBR) have proven to be efficient systems to culture mammalian cells at very high cell density in perfusion mode, thus leading to very high volumetric productivity. However, the immobilized cells must be continuously supplied with all nutrients in sufficient quantities to remain viable and productive over the full duration of the perfusion culture. Among all nutrients, oxygen is the most critical since it is present at very low concentration due to its low solubility in cell culture medium. This work presents the development of a model for oxygenation in a packed-bed bioreactor system. The experimental system used to develop the model was a packed-bed of Fibra-Cel disk carriers used to cultivate Chinese Hamster Ovary cells at high density ( approximately 6.1 x 10(7) cell/mL) in perfusion mode. With the help of this model, it was possible to identify if a PBR system is operated in optimal or sub-optimal conditions. Using the model, two options were proposed, which could improve the performance of the basal system by about twofold, that is, by increasing the density of immobilized cells per carrier volume from 6.1 x 10(7) to 1.2 x 10(8) cell/mL, or by increasing the packed-bed height from 0.2 to 0.4 m. Both strategies would be rather simple to test and implement in the packed-bed bioreactor system used for this study. As a result, it would be possible to achieve a substantial improvement of about twofold higher productivity as compared with the basal conditions.

  2. Ultrafast growth of single-crystal graphene assisted by a continuous oxygen supply

    NASA Astrophysics Data System (ADS)

    Xu, Xiaozhi; Zhang, Zhihong; Qiu, Lu; Zhuang, Jianing; Zhang, Liang; Wang, Huan; Liao, Chongnan; Song, Huading; Qiao, Ruixi; Gao, Peng; Hu, Zonghai; Liao, Lei; Liao, Zhimin; Yu, Dapeng; Wang, Enge; Ding, Feng; Peng, Hailin; Liu, Kaihui

    2016-11-01

    Graphene has a range of unique physical properties and could be of use in the development of a variety of electronic, photonic and photovoltaic devices. For most applications, large-area high-quality graphene films are required and chemical vapour deposition (CVD) synthesis of graphene on copper surfaces has been of particular interest due to its simplicity and cost effectiveness. However, the rates of growth for graphene by CVD on copper are less than 0.4 μm s-1, and therefore the synthesis of large, single-crystal graphene domains takes at least a few hours. Here, we show that single-crystal graphene can be grown on copper foils with a growth rate of 60 μm s-1. Our high growth rate is achieved by placing the copper foil above an oxide substrate with a gap of ∼15 μm between them. The oxide substrate provides a continuous supply of oxygen to the surface of the copper catalyst during the CVD growth, which significantly lowers the energy barrier to the decomposition of the carbon feedstock and increases the growth rate. With this approach, we are able to grow single-crystal graphene domains with a lateral size of 0.3 mm in just 5 s.

  3. Ultrafast growth of single-crystal graphene assisted by a continuous oxygen supply.

    PubMed

    Xu, Xiaozhi; Zhang, Zhihong; Qiu, Lu; Zhuang, Jianing; Zhang, Liang; Wang, Huan; Liao, Chongnan; Song, Huading; Qiao, Ruixi; Gao, Peng; Hu, Zonghai; Liao, Lei; Liao, Zhimin; Yu, Dapeng; Wang, Enge; Ding, Feng; Peng, Hailin; Liu, Kaihui

    2016-11-01

    Graphene has a range of unique physical properties and could be of use in the development of a variety of electronic, photonic and photovoltaic devices. For most applications, large-area high-quality graphene films are required and chemical vapour deposition (CVD) synthesis of graphene on copper surfaces has been of particular interest due to its simplicity and cost effectiveness. However, the rates of growth for graphene by CVD on copper are less than 0.4 μm s(-1), and therefore the synthesis of large, single-crystal graphene domains takes at least a few hours. Here, we show that single-crystal graphene can be grown on copper foils with a growth rate of 60 μm s(-1). Our high growth rate is achieved by placing the copper foil above an oxide substrate with a gap of ∼15 μm between them. The oxide substrate provides a continuous supply of oxygen to the surface of the copper catalyst during the CVD growth, which significantly lowers the energy barrier to the decomposition of the carbon feedstock and increases the growth rate. With this approach, we are able to grow single-crystal graphene domains with a lateral size of 0.3 mm in just 5 s.

  4. Autotrophic nitrogen removal in sequencing batch biofilm reactors at different oxygen supply modes.

    PubMed

    Wantawin, C; Juateea, J; Noophan, P L; Munakata-Marr, J

    2008-01-01

    Conventional nitrification-denitrification treatment is a common way to treat nitrogen in wastewater, but this process is costly for low COD/N wastewaters due to the addition of air and external carbon-source. However, ammonia may alternatively be converted to dinitrogen gas by autotrophic bacteria utilizing aerobically autotrophically produced nitrite as an electron acceptor under anoxic conditions. Lab-scale sequencing batch biofilm reactors (SBBRs) inoculated with normal nitrifying sludge were employed to study the potential of an oxygen-limited autotrophic nitrification-denitrification process initiated with typical nitrifying sludge for treating a synthetic ammonia wastewater devoid of organic carbon in one step. The ring-laced fibrous carrier (length 0.32 m, surface area 3.4 m2/m) was fixed vertically in a 3 L reactor. Two different air supply modes were applied:continuous aeration to control dissolved oxygen at 1.5 mg/L and intermittent aeration. High nitrogen removals of more than 50% were obtained in both SBBRs. At an ammonia loading of 0.882 gm N/m2-day [hydraulic retention time (HRT) of 24 hr], the SBBR continuously aerated to 1.5 mg DO/L had slightly higher nitrogen removal (64%) than the intermittently alternated SBBR (55%). The main form of residual nitrogen in the effluent was ammonia, at concentrations of 25 mg/L and 37 mg N/L in continuous and intermittent aeration SBBRs, respectively. Ammonia was completely consumed when ammonia loading was reduced to 0.441 gm N/m2-day [HRT extended to 48 hr]. The competitive use of nitrite by aerobic nitrite oxidizing bacteria (ANOB) with anaerobic ammonia-oxidizing bacteria (anammox bacteria) during the expanded aeration period under low remaining ammonia concentration resulted in higher nitrate production and lower nitrogen loss in the continuous aeration SBBR than in the intermittent aeration SBBR. The nitrogen removal efficiencies in SBBRs with continuous and alternating aerated were 80% and 86% respectively

  5. Oxygen supply in Bacillus thuringiensis fermentations: bringing new insights on their impact on sporulation and δ-endotoxin production.

    PubMed

    Boniolo, Fabrízio Siqueira; Rodrigues, Raphael Cardoso; Prata, Arnaldo Márcio Ramalho; López, Maria Luisa; Jacinto, Tânia; da Silveira, Mauricio Moura; Berbert-Molina, Marília Amorim

    2012-05-01

    The growth kinetics, sporulation, and toxicity of Bacillus thuringiensis var. israelensis were evaluated through the analysis of batch cultures with different dissolved oxygen (DO) profiles. Firstly, DO was maintained constant at 5%, 20%, or 50% throughout fermentation in order to identify the most suitable one to improve the main process parameters. Higher biomass concentration, cell productivity, and cell yield based on glucose were obtained with 50% DO. The higher aeration level also resulted in higher spore counts and markedly improved the toxic activity of the fermentation broth, which was 9-fold greater than that obtained with 5% DO (LC(50) of 39 and 329 mg/L, respectively). Subsequently, using a two-stage oxygen supply strategy, DO was kept at 50% during the vegetative and transition phases until the maximum cell concentration was achieved. Then, DO was changed to 0%, 5%, 20%, or 100% throughout sporulation and cell lysis phases. The interruption of oxygen supply strongly reduced the spore production and thoroughly repressed the toxin synthesis. On the contrary, when DO was raised to 100% of saturation, toxic activity increased approximately four times (LC(50) of 8.2 mg/L) in comparison with the mean values reached with lower DO levels, even though spore counts were lower than that from the 50% DO assay. When pure oxygen was used instead of normal air, it was possible to obtain 70% of the total biomass concentration achieved in the air assays; however, cultures did not sporulate and the toxin synthesis was consequently suppressed.

  6. Oxygen supply and consumption in the retina: implications for studies of retinopathy of prematurity.

    PubMed

    Cringle, Stephen J; Yu, Dao-Yi

    2010-02-01

    A disrupted oxygen environment in the retina of severely premature neonates is thought to be a key factor in the development of retinopathy of prematurity (ROP). This review describes our understanding of intraretinal oxygen distribution and consumption in a range of animal models, including species with naturally avascular retinas and models of induced occlusion of the retinal vasculature. The influence of graded systemic hyperoxia on retinal oxygenation is also discussed along with modulation of retinal oxygen metabolism. The differences in retinal oxygenation between developing and mature retinas are also described. Comparisons are made with studies in the monkey retina in order to assess possible similarities in behaviour between rat and human retinas. Pathogenesis mechanism and possible intervention strategies during the diseased processes in ROP are proposed based on our current knowledge.

  7. Culture scale-up studies as seen from the viewpoint of oxygen supply and dissolved carbon dioxide stripping.

    PubMed

    Matsunaga, Naoki; Kano, Kenjiro; Maki, Yasuyuki; Dobashi, Toshiaki

    2009-04-01

    Oxygen supply and dissolved carbon dioxide (dCO(2)) stripping are two of the most important control parameters in cell culture. In this study, we investigated the effect of scale-up on the volumetric gas transfer coefficient with bioreactors of different sizes (working volume: 80 L, 500 L, 2000 L, and 10,000 L; aspect ratio: 1.0-1.6). Sparging air into water increased the volumetric oxygen transfer coefficient (k(L)a), an index of oxygen supply efficiency, by scale-up roughly in proportion to the depth of the water. A corresponding increase in k(L)a was found in a real cell culture of Chinese hamster ovary cells. dCO(2) stripping efficiency was evaluated in water tests using changes in k(L)a(co2), an index defined in relation to k(L)a. k(L)a(co2) increased following surface aeration, but the rate of increase was reduced by scale-up, which was attributed to a decrease in the liquid surface-to-volume ratio. A similar decrease in efficiency was observed in a 2000 L bioreactor by increasing the liquid volume at constant liquid surface area. The observed scale-up effects are discussed based on a simple theoretical consideration.

  8. High hydrogen peroxide concentration in the feed-zone affects bioreactor cell productivity with liquid phase oxygen supply strategy.

    PubMed

    Sarkar, Pritish; Ghosh, Kaushik; Suraishkumar, G K

    2008-06-01

    Liquid phase oxygen supply strategy (LPOS), in which hydrogen peroxide (H(2)O(2)) is used to supply oxygen to the bioreactor, leads to low cell productivity despite high specific productivities of relevant metabolites. We hypothesized that high H(2)O(2) concentrations in the feed-zone led to local cell death, which in turn, lead to lower cell productivity. To test the hypothesis, a mathematical model was developed. Bacillus subtilis 168 was used as the model system in this study. The model simulations of cell concentrations in the bioreactor-zone were verified with the experimental results. The feed-zone H(2)O(2) concentrations remained 12-14 times higher than bulk bioreactor concentrations. The high local concentrations are expected to cause local cell killing, which explains the decrease in overall cell production by 50% at 300 rpm compared to conventional cultivation. Further, among the four different feed strategies studied using the model, dissolved oxygen (DO) controlled H(2)O(2) feed strategy caused least local cell killing and improved overall cell production by 34%.

  9. Enhanced performance of an air-cathode microbial fuel cell with oxygen supply from an externally connected algal bioreactor.

    PubMed

    Kakarla, Ramesh; Kim, Jung Rae; Jeon, Byong-Hun; Min, Booki

    2015-11-01

    An algae bioreactor (ABR) was externally connected to air-cathode microbial fuel cells (MFCs) to increase power generation by supplying a high amount of oxygen to cathode electrode. The MFC with oxygen fed from ABR produced maximum cell voltage and cathode potential at a fixed loading of 459 mV and 10 mV, respectively. During polarization analysis, the MFC displayed a maximum power density of 0.63 W/m(2) (at 2.06 A/m(2)) using 39.2% O2 from ABR, which was approximately 30% higher compared with use of atmospheric air (0.44 W/m(2), 20.8% O2,). The cyclic voltammogram analysis exhibited a higher reduction current of -137 mA with 46.5% O2 compared to atmospheric air (-115 mA). Oxygen supply by algae bioreactor to air-cathode MFC could also maintain better MFC performance in long term operation by minimizing cathode potential drop over time.

  10. Reliability of the Gas Supply in the Air Force Emergency Passenger Oxygen System

    DTIC Science & Technology

    2005-10-01

    to be intact. A hypodermic needle was attached to the sampling line of a mass spectrometer (Perkin-El- mer, Model MGA-1100). The needle was inserted...Emergency Passenger Oxygen System (EPOS; Fig. 1) was alleged to have significant numbers of inadequate oxygen cylinders. In theory , this could prevent the...hypothetical analysis demonstrates the disparity between a manufacturing specifi cation of a component and the overall performance of a device. This

  11. Development of a Novel Oxygen Supply Process and its Integration with an Oxy-Fuel Coal-Fired Boiler

    SciTech Connect

    2006-12-31

    BOC, the world's second largest industrial gas company, has developed a novel high temperature sorption based technology referred to as CAR (Cyclic Autothermal Recovery) for oxygen production and supply to oxy-fuel boilers with flue gas recycle. This technology is based on sorption and storage of oxygen in a fixed bed containing mixed ionic and electronic conductor materials. The objective of the proposed work was to construct a CAR PDU that was capable of producing 10-scfm of oxygen, using steam or recycled flue gas as the sweep gas, and install it in the Combustion Test Facility. The unit was designed and fabricated at BOC/The Linde Group, Murray Hill, New Jersey. The unit was then shipped to WRI where the site had been prepared for the unit by installation of air, carbon dioxide, natural gas, nitrogen, computer, electrical and infrastructure systems. Initial experiments with the PDU consisted of flowing air into both sides of the absorption systems and using the air heaters to ramp up the bed temperatures. The two beds were tested individually to operational temperatures up to 900 C in air. The cycling process was tested where gases are flowed alternatively from the top then bottom of the beds. The PDU unit behaved properly with respect to flow, pressure and heat during tests. The PDU was advanced to the point where oxygen production testing could begin and integration to the combustion test facility could occur.

  12. The development of a non-cryogenic nitrogen/oxygen supply system

    NASA Technical Reports Server (NTRS)

    Greenough, B. M.

    1972-01-01

    Development of the hydrazine/water electrolysis process in a manned spacecraft to provide metabolic oxygen and both oxygen and nitrogen for cabin leakage makeup was studied. Electrode development efforts were directed to stability, achieved with catalyst additives and improved processing techniques, and a higher hydrazine conversion efficiency, achieved by reducing catalyst loading on the cathodes. Extensive testing of the one-man breadboard N2/02 system provided complete characterization of cabin atmosphere control aspects. A detailed design of a prototype modular N2/02 unit was conducted. The contact heat exchanger which is an integral component of this design was fabricated and sucessfully design-verification tested.

  13. Propulsion requirements for the supply of lunar-derived oxygen for a manned Mars mission

    NASA Technical Reports Server (NTRS)

    Wrobel, J. Richard; Butterfield, Ansel J.; Garrett, L. Bernard

    1989-01-01

    The use of lunar-derived liquid oxygen with hydrogen for robust manned explorations beyond earth is discussed. The propellant mixture ratio for optimal performance is near the current design point of r = 6. The results of NASA-sponsored studies of missions using cryogenic bipropellant H2-O2 for most functions reveal the potential benefits from a propellant terminal in cis-lunar space. The main propulsion technologies associated with Mars mission case studies include: in-space fluid transfer, zero-g ignition, oxygen-enriched propellant mixtures, throttling of main engines, and H2-O2 based auxiliary propulsion.

  14. Haemoglobin as a buoyancy regulator and oxygen supply in the backswimmer (Notonectidae, Anisops).

    PubMed

    Matthews, Philip G D; Seymour, Roger S

    2008-12-01

    Unlike all other diving insects, backswimmers of the genus Anisops can exploit the pelagic zone by temporarily achieving near-neutral buoyancy during the course of a dive. They begin a dive positively buoyant due to the large volume of air carried in their ventral air-stores, but rapidly enter a protracted period of near-neutral buoyancy before becoming negatively buoyant. This dive profile is due to haemoglobin found in large tracheated cells in the abdomen. Fibre optic oxygen probes placed in the air-stores of submerged bugs revealed that oxygen partial pressure (P(O(2))) dropped in a sigmoid curve, where a linear decline preceded a plateau between 5.1 and 2.0 kPa, before a final drop. Buoyancy measurements made by attaching backswimmers to a sensitive electronic balance showed the same three phases. Inactivating the haemoglobin by fumigating backswimmers with 15% CO eliminated both buoyancy and P(O(2)) plateaus. Oxygen unloaded from the haemoglobin stabilises the air-store during the neutrally buoyant phase after a decrease in volume of between 16% and 19%. Using measurements of air-store P(O(2)) and volume, it was calculated that during a dive the haemoglobin and air-store contribute 0.25 and 0.26 microl of oxygen, respectively.

  15. Power generation capabilities of microbial fuel cells with different oxygen supplies in the cathodic chamber.

    PubMed

    Juang, Der-Fong; Lee, Chao-Hsien; Hsueh, Shu-Chun; Chou, Huei-Yin

    2012-06-01

    Two microbial fuel cells (MFCs) inoculated with activated sludge of a wastewater treatment plant were constructed. Oxygen was provided by mechanical aeration in the cathodic chamber of one MFC, whereas it was obtained by the photosynthesis of algae in the other. Electrogenic capabilities of both MFCs were compared under the same operational conditions. Results showed that the MFC with mechanical aeration in the cathodic chamber displayed higher power output than the one with photosynthesis of algae. Good linear relationship between power density and chemical oxygen demand (COD) loading rate was obtained only on the MFC with mechanical aeration. Furthermore, the relationships between power density and effluent COD and between Coulombic efficiency and COD loading rate can only be expressed as binary quadratic equations for the MFC with mechanical aeration and not for the one with photosynthesis of algae.

  16. Nifedipine improves blood flow and oxygen supply, but not steady-state oxygenation of tumours in perfusion pressure-controlled isolated limb perfusion.

    PubMed

    Thews, O; Hummel, M; Kelleher, D K; Lecher, B; Vaupel, P

    2002-12-02

    Isolated limb perfusion allows the direct application of therapeutic agents to a tumour-bearing extremity. The present study investigated whether the dihydropyridine-type Ca(2+)-channel blocker nifedipine could improve blood flow and oxygenation status of experimental tumours during isolated limb perfusion. Perfusion was performed by cannulation of the femoral artery and vein in rats bearing DS-sarcoma on the hind foot dorsum. Perfusion rate was adjusted to maintain a perfusion pressure of 100-140 mmHg throughout the experiment. Following equilibration, nifedipine was continuously infused for 30 min (8.3 microg min(-1) kg(-1) BW). During constant-pressure isolated limb perfusion, nifedipine can significantly increase perfusion rate (+100%) and RBC flux (+60%) through experimental leg tumours. "Steal phenomena" in favour of the surrounding normal tissue and oedema formation were not observed. Despite the increased oxygen availability (+63%) seen upon application of this calcium channel blocker, nifedipine does not result in a substantial reduction of tumour hypoxia, most probably due to an increase in O(2) uptake with rising O(2) supply to the tumour-bearing hind limb. Nifedipine application during isolated limb perfusion can enhance tumour microcirculation and may therefore promote the delivery (pharmacokinetics) of anti-cancer drugs to the tumour and by this improve the efficacy of pressure-controlled isolated limb perfusion.

  17. Development of a non-cryogenic nitrogen/oxygen supply system. [for spacecraft environments

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Modular components were refined or replaced to improve the performance of the electrolysis module in a system which generates both oxygen and hydrogen from hydrazine hydrate. Significant mechanical and electrical performance improvements were achieved in the cathode. Improvements were also made in the phase separation area but at considerable cost in time and money and to the detriment of other investigative areas. Only the pump/bubble separator failed in a manner necessitating redesign. Its failure was, however, due to its being operated above the temperature range for which it was designed. The basic electrolysis cell design was not changed.

  18. Anodic aluminium oxide membranes for immunoisolation with sufficient oxygen supply for pancreatic islets.

    PubMed

    Cho, Siwoo; Lee, Sangmin; Jeong, Seong Hee; Kim, Yeongae; Kim, Song Cheol; Hwang, Woonbong; Park, Jaesung

    2013-05-01

    Immunoisolation membranes have been developed for various cell encapsulations for therapeutic purposes. However effective encapsulation systems have been hindered by low oxygen (O2) permeability or imperfect immunoisolation caused by either low porosity or non-uniform pore geometry. Here, we report an encapsulation method that uses an anodic aluminum oxide membrane formed by polyethylene oxide self-assembly to obtain nanochannels with both high selectivity in excluding immune molecules and high permeability of nutrients such as glucose, insulin, and O2. The extracorporeal encapsulation system composed of these membranes allows O2 flux to meet the O2 demand of pancreatic islets of Langerhans and provides excellent in vitro viability and functionality of islets.

  19. Significant improvement of Serratia marcescens lipase fermentation, by optimizing medium, induction, and oxygen supply.

    PubMed

    Long, Zhang-De; Xu, Jian-He; Pan, Jiang

    2007-08-01

    Production of an extracellular lipase from Serratia marcescens ECU1010, which is an industrially important biocatalyst for the stereospecific synthesis of Diltiazem precursor, was carefully optimized in both shake flasks and a fermenter, using Tween-80 as the enzyme inducer. Dextrin and beef extract combined with ammonium sulfate were indicated to be the best carbon and nitrogen sources, respectively. With the increase of Tween-80 from 0 to 10 g l-1, the lipase production was greatly enhanced from merely 250 U l-1 to a maximum of 3,340 U l-1, giving the highest lipase yield of ca 640 U g-1 dry cell mass (DCW), although the maximum biomass (6.0 g DCW l-1) was achieved at 15 g l-1 of Tween-80. When the medium loading in shake flasks was reduced from 20 to 10% (v / v), the lipase production was significantly enhanced. The increase in shaking speed also resulted in an improvement of the lipase production, although the cell growth was slightly repressed, suggesting that the increase of dissolved oxygen (DO) concentration contributed to the enhancements of lipase yield. When the lipase fermentation was carried out in a 5-l fermenter, the lipase production reached a new maximum of 11,060 U l-1 by simply raising the aeration rate from 0.5 to 1.0 vvm, while keeping the dissolved oxygen above 20% saturation via intermittent adjustment of the agitation speed (> or =400 rpm), in the presence of a relatively low concentration (2 g l-1) of Tween-80 to prevent a potential foaming problem, which is easy to occur in the intensively aerated fermenter.

  20. Oxygen supplies for hospitals in Papua New Guinea: a comparison of the feasibility and cost-effectiveness of methods for different settings.

    PubMed

    Duke, Trevor; Peel, David; Wandi, Francis; Subhi, Rami; Sa'avu Martin; Matai, Sens

    2010-01-01

    Oxygen therapy is essential in all wards, emergency departments and operating theatres of hospitals at all levels, and oxygen is life-saving. In Papua New Guinea (PNG), an effective oxygen system that improved the detection and treatment of hypoxaemia in provincial and district hospitals reduced death rates from pneumonia in children by as much as 35%. The methods for providing oxygen in PNG are reviewed. A busy provincial hospital will use on average about 38,000 l of oxygen each day. Over 2 years the cost of this amount of oxygen being provided by cylinders (at least K555,000) or an oxygen generator (about K1 million) is significantly more than the cost of setting up and maintaining a comprehensive system of bedside oxygen concentrators (K223,000). A district hospital will use 17,000 l per day. The full costs of this over 2 years are K33,000 if supplied by bedside concentrators, or K333,000 plus transport costs if the oxygen source is cylinders. In provincial and district hospitals bedside oxygen concentrators will be the most cost-effective, simple and reliable sources of oxygen. In large hospitals where there are existing oxygen pipelines, or in newly designed hospitals, an oxygen generator will be effective but currently much more expensive than bedside concentrators that provide the same volume of oxygen generation. There are options for oxygen concentrator use in hospitals and health centres that do not have reliable power. These include battery storage of power or solar power. While these considerably add to the establishment cost when changing from cylinders to concentrators, a battery-powered system should repay its capital costs in less than one year, though this has not yet been proven in the field. Bedside oxygen concentrators are currently the 'best-buy' in supplying oxygen in most hospitals in PNG, where cylinder oxygen is the largest single item in their drug budget. Oxygen concentrators should not be seen as an expensive intervention that has to

  1. External supply of oxygen to the atmospheres of the giant planets.

    PubMed

    Feuchtgruber, H; Lellouch, E; de Graauw, T; Bézard, B; Encrenaz, T; Griffin, M

    1997-09-11

    The atmospheres of the giant planets are reducing, being mainly composed of hydrogen, helium and methane. But the rings and icy satellites that surround these planets, together with the flux of interplanetary dust, could act as important sources of oxygen, which would be delivered to the atmospheres mainly in the form of water ice or silicate dust. Here we report the detection, by infrared spectroscopy, of gaseous H2O in the upper atmospheres of Saturn, Uranus and Neptune. The implied H2O column densities are 1.5 x 10(15), 9 x 10(13) and 3 x 10(14) molecules cm(-2) respectively. CO2 in comparable amounts was also detected in the atmospheres of Saturn and Neptune. These observations can be accounted for by external fluxes of 10(5)-10(7) H2O molecules cm(-2) s(-1) and subsequent chemical processing in the atmospheres. The presence of gaseous water and infalling dust will affect the photochemistry, energy budget and ionospheric properties of these atmospheres. Moreover, our findings may help to constrain the injection rate and possible activity of distant icy objects in the Solar System.

  2. The effect of hepatic vascular exclusion on hepatic blood flow and oxygen supply--uptake ratio in the pig.

    PubMed

    López Santamaria, M; Gamez, M; Murcia, J; Paz Cruz, J A; Bueno, J; Canser, E; Qi, B; Lobato, R; Martinez, L; Jara, P; Tovar, J A

    1997-10-01

    The hemodynamic disturbances produced by total hepatic vascular exclusion (THVE) for 40 minutes were studied in 7 pigs (19-22 kg). THVE was produced by clamping the hepatic pedicle and inferior vena cava, above and below the liver, for a 40-minutes period, followed by unclamping. Compared to baseline values, 30 minutes after onset of THVE, there was a decrease in cardiac output (3.86 +/- 0.55 vs 1.23 +/- 0.23 L x min-1), systemic arterial pressure (97.54 +/- 13.58 vs 43.43 +/- 11.38 mm Hg), and pulmonary artery pressure (16.57 +/- 6.38 vs 12.57 +/- 3.58) and an increase in systemic and pulmonary vascular resistance (1772 +/- 198 vs 2351 +/- 462, and 182 +/- 66 vs 361 +/- 124 dyn x s x cm-5 respectively). As a result of diminished cardiac output, the systemic oxygen supply decreased (461 +/- 131 vs 101 +/- 46 ml x min-1), but the systemic oxygen extraction rate rose from 17.3% t0 31.2%. Thirty minutes after unclamping, the changes had reversed and all the parameters tended to normalize. Total hepatic blood flow 30 minutes after unclamping was higher than at baseline (5.08 +/- 1.2 vs 6.66 +/- 0.67 ml x min-1 x 100 g-1), because of the increase in portal blood flow (4.52 +/- 1.21 vs 6.07 +/- 0.70 ml x min-1 x 100 g-1). There were no significant differences in hepatic oxygen supply and uptake at baseline and after unclamping (152.6 +/- 23.0 vs 187.0 +/- 34.7 and 22.7 +/- 4.9 vs 28.7 +/- 8.4 ml O2 respectively). AST rose (29 +/- 7 vs 136 +/- 91 U/l), but there was no change in the remaining liver enzymes, glucose, creatinine and serum electrolytes, so we conclude that the hemodynamic disturbances produced by 40 minutes of THVE are manageable and spontaneously reversible. Liver metabolism was not greatly disturbed, so THVE was judged to be a viable technique to be added to the surgeon's range of options.

  3. Features of a SINDA/FLUINT model of a liquid oxygen supply line

    NASA Technical Reports Server (NTRS)

    Simmonds, Boris G.

    1993-01-01

    The modeling features used in a steady-state heat transfer problem using SINDA/FLUINT are described. The problem modeled is a 125 feet long, 3 inch diameter pipe, filled with liquid oxygen flow driven by a given pressure gradient. The pipe is fully insulated in five sections. Three sections of 1 inch thick spray-on foam and two sections of vacuum jacket. The model evaluates friction, turns losses and convection heat transfer between the fluid and the pipe wall. There is conduction through the foam insulation with temperature dependent thermal conductivity. The vacuum space is modeled with radiation and gas molecular conduction, if present, in the annular gap. Heat is transferred between the outer surface and surrounding ambient by natural convection and radiation; and, by axial conduction along the pipe and through the vacuum jacket spacers and welded seal flanges. The model makes extensive use of SINDA/FLUINT basic capabilities such as the GEN option for nodes and conductors (to generate groups of nodes or conductors), the SIV option (to generate single, temperature varying conductors), the SIM option (for multiple, temperature varying conductors) and the M HX macros for fluids (to generate strings of lumps, paths, and ties representing a diabatic duct). It calls subroutine CONTRN (returns the relative location in the G-array of a network conductor, given an actual conductor number) enabling an extensive manipulation of conductor (calculates an assignment of their values) with DO loops. Models like this illustrate to the new and even to the old SINDA/FLUINT user, features of the program that are not so obvious or known, and that are extremely handy when trying to take advantage of both, the automation of the DATA headers and make surgical modifications to specific parameters of the thermal or fluid elements in the OPERATIONS portion of the model.

  4. Features of a SINDA/FLUINT model of a liquid oxygen supply line

    NASA Astrophysics Data System (ADS)

    Simmonds, Boris G.

    1993-11-01

    The modeling features used in a steady-state heat transfer problem using SINDA/FLUINT are described. The problem modeled is a 125 feet long, 3 inch diameter pipe, filled with liquid oxygen flow driven by a given pressure gradient. The pipe is fully insulated in five sections. Three sections of 1 inch thick spray-on foam and two sections of vacuum jacket. The model evaluates friction, turns losses and convection heat transfer between the fluid and the pipe wall. There is conduction through the foam insulation with temperature dependent thermal conductivity. The vacuum space is modeled with radiation and gas molecular conduction, if present, in the annular gap. Heat is transferred between the outer surface and surrounding ambient by natural convection and radiation; and, by axial conduction along the pipe and through the vacuum jacket spacers and welded seal flanges. The model makes extensive use of SINDA/FLUINT basic capabilities such as the GEN option for nodes and conductors (to generate groups of nodes or conductors), the SIV option (to generate single, temperature varying conductors), the SIM option (for multiple, temperature varying conductors) and the M HX macros for fluids (to generate strings of lumps, paths, and ties representing a diabatic duct). It calls subroutine CONTRN (returns the relative location in the G-array of a network conductor, given an actual conductor number) enabling an extensive manipulation of conductor (calculates an assignment of their values) with DO loops. Models like this illustrate to the new and even to the old SINDA/FLUINT user, features of the program that are not so obvious or known, and that are extremely handy when trying to take advantage of both, the automation of the DATA headers and make surgical modifications to specific parameters of the thermal or fluid elements in the OPERATIONS portion of the model.

  5. Kinetic study and oxygen transfer efficiency evaluation using respirometric methods in a submerged membrane bioreactor using pure oxygen to supply the aerobic conditions.

    PubMed

    Rodríguez, Francisco A; Poyatos, José M; Reboleiro-Rivas, Patricia; Osorio, Francisco; González-López, Jesús; Hontoria, Ernesto

    2011-05-01

    The performance of a wastewater bench-scale ultrafiltration membrane bioreactor (MBR) treatment plant using pure oxygen to supply the aerobic conditions for 95 days was studied. The results showed the capacity of the MBR systems to remove organic material under a hydraulic retention time of 12h and a sludge retention time of 39.91 days. Aeration represents its major power input; this is why the alpha-factor of the aeration and kinetic parameters (design parameters) were determined when the mixed liquid suspended solids (MLSS) was increased from 3420 to 12,600 mg/l in order to understand the system. An alpha-factor in the range 0.462-0.022 and the kinetic parameters measured with the respirometric method (K(M) of 73.954-3.647 mg/l, k(d) of 0.0142-0.104 day(-1), k(H) of 0.1266-0.655 day(-1), and the yield mean coefficient of 0.941) were obtained. Our study suggested significant changes in the behaviour of the biological system when the concentration of MLSS was increased.

  6. Influence of sludge retention time and temperature on the sludge removal in a submerged membrane bioreactor: comparative study between pure oxygen and air to supply aerobic conditions.

    PubMed

    Rodríguez, F A; Leyva-Díaz, J C; Reboleiro-Rivas, P; González-López, J; Hontoria, E; Poyatos, J M

    2014-01-01

    Performance of a bench-scale wastewater treatment plant, which consisted of a membrane bioreactor, was monitored daily using pure oxygen and air to supply aerobic conditions with the aim of studying the increases of the aeration and sludge removal efficiencies and the effect of the temperature. The results showed the capacity of membrane bioreactor systems for removing organic matter. The alpha-factors of the aeration were determined for six different MLSS concentrations in order to understand the system working when pure oxygen and air were used to supply aerobic conditions in the system. Aeration efficiency was increased between 30.7 and 45.9% when pure oxygen was used in the operation conditions (a hydraulic retention time of 12 h and MLSS concentrations between 4,018 and 11,192 mg/L). Sludge removal efficiency increased incrementally, from 0.2 to 1.5% when pure oxygen was used at low sludge retention time and from 1.5% to 15.4% at medium sludge retention time when temperature conditions were lower than 20°C. Moreover, the difference between calculated and experimental sludge retention time was lesser when pure oxygen was used to provide aerobic conditions, so the influence of the temperature decreased when the pure oxygen was used. These results showed the convenience of using pure oxygen due to the improvement in the performance of the system.

  7. Oxygen diffusion: an enzyme-controlled variable parameter.

    PubMed

    Erdmann, Wilhelm; Kunke, Stefan

    2014-01-01

    Previous oxygen microelectrode studies have shown that the oxygen diffusion coefficient (DO₂) increases during extracellular PO₂ decreases, while intracellular PO₂ remained unchanged and thus cell function (spike activity of neurons). Oxygen dependency of complex multicellular organisms requires a stable and adequate oxygen supply to the cells, while toxic concentrations have to be avoided. Oxygen brought to the tissue by convection diffuses through the intercellular and cell membranes, which are potential barriers to diffusion. In gerbil brain cortex, PO₂ and DO₂ were measured by membrane-covered and by bare gold microelectrodes, as were also spike potentials. Moderate respiratory hypoxia was followed by a primary sharp drop of tissue PO₂ that recovered to higher values concomitant with an increase of DO₂. A drop in intracellular PO₂ recovered immediately. Studies on the abdominal ganglion of aplysia californica showed similar results.Heterogeneity is a feature of both normal oxygen supply to tissue and supply due to a wide range of disturbances in oxygen supply. Oxygen diffusion through membranes is variable thereby ensuring adequate intracellular PO₂. Cell-derived glucosamine oxidase seems to regulate the polymerization/depolymerisation ratio of membrane mucopolysaccharides and thus oxygen diffusion.Variability of oxygen diffusion is a decisive parameter for regulating the supply/demand ratio of oxygen supply to the cell; this occurs in highly developed animals as well as in species of a less sophisticated nature. Autoregulation of oxygen diffusion is as important as the distribution/perfusion ratio of the capillary meshwork and as the oxygen extraction ratio in relation to oxygen consumption of the cell. Oxygen diffusion resistance is the cellular protection against luxury oxygen supply (which can result in toxic oxidative species leading to mutagenesis).

  8. Effects of irradiation distance on supply of reactive oxygen species to the bottom of a Petri dish filled with liquid by an atmospheric O2/He plasma jet

    NASA Astrophysics Data System (ADS)

    Kawasaki, Toshiyuki; Kusumegi, Shota; Kudo, Akihiro; Sakanoshita, Tomohiro; Tsurumaru, Takuya; Sato, Akihiro; Uchida, Giichiro; Koga, Kazunori; Shiratani, Masaharu

    2016-05-01

    The impact of irradiation distances on plasma jet-induced specific effects on the supply of reactive oxygen species (ROS) to the bottom of a Petri dish filled with liquid was investigated using a KI-starch gel reagent that can be employed as a ROS indicator even in water. O3 exposure experiments without plasma irradiation were also performed to elucidate the specific effects of the plasma jet. Relative concentrations of ROS transported to the bottom were evaluated using absorbance measurements. The results indicated that ROS supply to the bottom is markedly enhanced by the plasma jet irradiation at shorter irradiation distances, whereas similar results could not be obtained for the O3 exposure. In these cases, the liquid mixing in the depth direction was also enhanced by the plasma jet irradiation only, and the supply of reactive atomic oxygen to the liquid surface was markedly increased as well.

  9. Myocardial oxygen supply/demand ratio in aortic stenosis: hemodynamic and echocardiographic evaluation of patients with and without angina pectoris.

    PubMed

    Nadell, R; DePace, N L; Ren, J F; Hakki, A H; Iskandrian, A S; Morganroth, J

    1983-08-01

    Angina pectoris is a common symptom in patients with aortic stenosis without coronary artery disease. To investigate the correlates of angina pectoris, echocardiographic and hemodynamic data from 44 patients with aortic stenosis and no coronary artery disease (mean age 56 +/- 10 years) were analyzed. Twenty-three patients had no angina pectoris and 21 patients had angina pectoris. The ratio of the diastolic pressure-time index (area between the aortic and left ventricular pressure curves during diastole) to the systolic pressure-time index (area under the left ventricular pressure curve during systole), an index of the oxygen supply/demand ratio, was not different in patients with or without angina pectoris. There were no differences between patients with and without angina pectoris in echocardiographically determined wall thickness, chamber size, systolic and diastolic wall stress and left ventricular mass; in electrocardiographically defined voltage; and in hemodynamically defined aortic valve area, transaortic gradient and stroke work index. Thus, echocardiographic and hemodynamic measurements at rest are not significantly different in the presence or absence of angina pectoris in patients with aortic stenosis. Dynamic data appear to be essential for evaluation of the mechanisms of angina pectoris in patients with aortic stenosis.

  10. Air-liquid interface cultures enhance the oxygen supply and trigger the structural and functional differentiation of intestinal porcine epithelial cells (IPEC).

    PubMed

    Nossol, Constanze; Diesing, A-K; Walk, N; Faber-Zuschratter, H; Hartig, R; Post, A; Kluess, J; Rothkötter, H-J; Kahlert, S

    2011-07-01

    The specific function of the epithelium as critical barrier between the intestinal lumen and the organism's internal microenvironment is reflected by permanent maintenance of intercellular junctions and cellular polarity. The intestinal epithelial cells are responsible for absorption of nutritional components, facing mechanical stress and a changing oxygen supplementation via blood stream. Oxygen itself can regulate the barrier and the absorptive function of the epithelium. Therefore, we compared the dish cell culture, the transwell-like membrane culture and the oxygen enriched air-liquid interface (ALI) culture. We demonstrated strong influence of the different culture conditions on morphology and function of intestinal porcine epithelial cell lines in vitro. ALI culture resulted in a significant increase in cell number, epithelial cell layer thickness and expression as well as apical localisation of the microvilli-associated protein villin. Remarkable similarities regarding the morphological parameters were observed between ALI cultures and intestinal epithelial cells in vivo. Furthermore, the functional analysis of protein uptake and degradation by the epithelial cells demonstrated the necessity of sufficient oxygen supply as achieved in ALI cultures. Our study is the first report providing marked evidence that optimised oxygen supply using ALI cultures directly affects the morphological differentiation and functional properties of intestinal epithelial cells in vitro.

  11. The influence of oxygen supply on metabolism of neural cells cultured on a gas-permeable PTFE foil.

    PubMed

    Mauth, Corinna; Pavlica, Sanja; Deiwick, Andrea; Steffen, Anja; Bader, Augustinus

    2010-01-01

    The influence of oxygen on neural stem cell proliferation, differentiation, and apoptosis is of great interest for regenerative therapies in neurodegenerative disorders, such as Parkinson's disease. These oxygen depending mechanisms have to been considered for the optimization of neural cell culture conditions. In this study, we used a cell culture system with an oxygen-permeable polytetrafluorethylene (PTFE) foil to investigate the effect of oxygen on metabolism and survival of neural cell lines in vitro. Human glial astrocytoma-derived cells (GOS-3) and rat pheochromacytoma cells (PC12) were cultured on the gas-permeable PTFE foil as well as a conventional non oxygen-permeable cell culture substrate at various oxygen concentrations. Analyses of metabolic activity, gene expression of apoptotic grade, and dopamine synthesis were performed. Under low oxygen partial pressure (2%, 5%) the anaerobic metabolism and apoptotic rate of cultured cells is diminished on PTFE foil when compared with the conventional culture dishes. In contrast, under higher oxygen atmosphere (21%) the number of apoptotic cells on the PTFE foil was enhanced. This culture model demonstrates a suitable model for the improvement of oxygen dependent metabolism under low oxygen conditions as well as for induction of oxidative stress by high oxygen atmosphere without supplementation of neurotoxins.

  12. Regulation of metabolic flux in Lactobacillus casei for lactic acid production by overexpressed ldhL gene with two-stage oxygen supply strategy.

    PubMed

    Ge, Xiang-Yang; Xu, Yan; Chen, Xiang; Zhang, Long-Yun

    2015-01-01

    This study describes a novel strategy to regulate the metabolic flux for lactic acid production in Lactobacillus casei. The ldhL gene encoding L-lactate dehydrogenase (L-LDH) was overexpressed in L. casei, and a two-stage oxygen supply strategy (TOS) that maintained a medium oxygen supply level during the early fermentation phase, and a low oxygen supply level in the later phase was carried out. As a consequence, a maximum L-LDH activity of 95.6 U/ml was obtained in the recombinant strain, which was over 4-fold higher than that of the initial strain. Under the TOS for L. casei (pMG-ldhL), the maximum lactic acid concentration of 159.6 g/l was obtained in 36 h, corresponding to a 62.8% increase. The results presented here provide a novel way to regulate the metabolic flux of L. casei for lactic acid production in different fermentation stages, which is available to enhance organic acid production in other strains.

  13. Options for Procuring Adequate Supplies of Petroleum Products.

    DTIC Science & Technology

    1981-07-01

    focuses on the procurement of bulk refined products within the United States in a peacetime environment. The number of potentially remedial actions...shortfalls (lack of coverage of requirements). We focus on the procurement of bulk refined product within the United States where shortfalls have been...products for the Department of Defense worldwide and for federal civilian agencies within the United States . Table 1 lists the quantities of various

  14. Oxygen Delivering Biomaterials for Tissue Engineering

    PubMed Central

    Farris, Ashley L.; Rindone, Alexandra N.; Grayson, Warren L.

    2016-01-01

    Tissue engineering (TE) has provided promising strategies for regenerating tissue defects, but few TE approaches have been translated for clinical applications. One major barrier in TE is providing adequate oxygen supply to implanted tissue scaffolds, since oxygen diffusion from surrounding vasculature in vivo is limited to the periphery of the scaffolds. Moreover, oxygen is also an important signaling molecule for controlling stem cell differentiation within TE scaffolds. Various technologies have been developed to increase oxygen delivery in vivo and enhance the effectiveness of TE strategies. Such technologies include hyperbaric oxygen therapy, perfluorocarbon- and hemoglobin-based oxygen carriers, and oxygen-generating, peroxide-based materials. Here, we provide an overview of the underlying mechanisms and how these technologies have been utilized for in vivo TE applications. Emerging technologies and future prospects for oxygen delivery in TE are also discussed to evaluate the progress of this field towards clinical translation. PMID:27453782

  15. Approaching the evolutionary advantage of ancillary types of haemoglobin in Daphnia magna by simulation of oxygen supply.

    PubMed

    Moenickes, S; Richter, O; Pirow, R

    2010-02-01

    The planktonic crustacean Daphnia magna synthesizes haemoglobin (Hb) macromolecules of variant subunit composition and oxygen affinity. This is one of the strategies by which the animals cope with variations in environmental conditions such as ambient oxygen tension. The enrichment of high-affinity Hb molecules in the haemolymph of hypoxia-exposed animals is thought to reduce Hb synthesis costs due to an enhanced transport efficiency of these molecules in comparison to the low-affinity Hb molecules. How great this economic advantage is, and under which conditions this benefit disappears, is still not fully understood. Here we implemented a rigorously simplified model of the daphnid body and described the transport of oxygen from the environment via the haemolymph to the tissues in terms of the convection-diffusion-reaction equation. The model was validated by comparing various model predictions with experimental data. A sensitivity analysis was used to evaluate the influence of parameter uncertainties on the model predictions. Cost-benefit analysis revealed in which way at the system's level the increase in Hb oxygen affinity improves the oxygen loading at the respiratory surfaces and impairs the release of oxygen to the tissues. The benefit arising from the improved oxygen loading exceeds the disadvantage of impaired unloading only under conditions where the ambient oxygen tension is critically low and the Hb concentration is high. The low-affinity Hb, on the other hand, provides an advantage given that the Hb concentration is low and the ambient oxygen tension is well above the critical level. Computer-aided modelling and simulation therefore provide valuable mechanistic insights into the driving forces that could have shaped the evolution of globin genes in daphnids.

  16. Establishing a physiological environment for visualized in vitro brain slice recordings by increasing oxygen supply and modifying aCSF content

    PubMed Central

    Hájos, Norbert; Mody, Istvan

    2009-01-01

    Our insights into the basic characteristics of neuronal function were significantly advanced by combining the in vitro slice technique with the visualization of neurons and their processes. The visualization through water immersion objectives requires keeping slices submerged in recording chambers where delivering artificial cerebro-spinal fluid (aCSF) at flow rates of 2–3 ml/min results in a limited oxygen supply [Hájos N, Ellender TJ, Zemankovics R, Mann EO, Exley R, Cragg SJ, et al. Maintaining network activity in submerged hippocampal slices: importance of oxygen supply. Eur J Neurosci 2009;29:319–27]. Here we review two methods aimed at providing sufficient oxygen levels to neurons in submerged slices to enable high energy consuming processes such as elevated firing rates or network oscillations. The use of these methods may also influence the outcome of other electrophysiological experiments in submerged slices including the study of intercellular signaling pathways. In addition, we also emphasize the importance of various aCSF constituents used in in vitro experiments. PMID:19524611

  17. The development of a non-cryogenic nitrogen/oxygen supply system. [using hydrazine/water electrolysis

    NASA Technical Reports Server (NTRS)

    Greenough, B. M.; Mahan, R. E.

    1974-01-01

    A hydrazine/water electrolysis process system module design was fabricated and tested to demonstrate component and module performance. This module is capable of providing both the metabolic oxygen for crew needs and the oxygen and nitrogen for spacecraft leak makeup. The component designs evolved through previous R and D efforts, and were fabricated and tested individually and then were assembled into a complete module which was successfully tested for 1000 hours to demonstrate integration of the individual components. A survey was made of hydrazine sensor technology and a cell math model was derived.

  18. Renal Doppler Resistive Index as a Marker of Oxygen Supply and Demand Mismatch in Postoperative Cardiac Surgery Patients

    PubMed Central

    Corradi, Francesco; Brusasco, Claudia; Paparo, Francesco; Manca, Tullio; Santori, Gregorio; Benassi, Filippo; Molardi, Alberto; Gallingani, Alan; Ramelli, Andrea; Gherli, Tiziano; Vezzani, Antonella

    2015-01-01

    Background and Objective. Renal Doppler resistive index (RDRI) is a noninvasive index considered to reflect renal vascular perfusion. The aim of this study was to identify the independent hemodynamic determinants of RDRI in mechanically ventilated patients after cardiac surgery. Methods. RDRI was determined in 61 patients by color and pulse Doppler ultrasonography of the interlobar renal arteries. Intermittent thermodilution cardiac output measurements were obtained and blood samples taken from the tip of pulmonary artery catheter to measure hemodynamics and mixed venous oxygen saturation (SvO2). Results. By univariate analysis, RDRI was significantly correlated with SvO2, oxygen extraction ratio, left ventricular stroke work index, and cardiac index, but not heart rate, central venous pressure, mean artery pressure, pulmonary capillary wedge pressure, systemic vascular resistance index, oxygen delivery index, oxygen consumption index, arterial lactate concentration, and age. However, by multivariate analysis RDRI was significantly correlated with SvO2 only. Conclusions. The present data suggests that, in mechanically ventilated patients after cardiac surgery, RDRI increases proportionally to the decrease in SvO2, thus reflecting an early vascular response to tissue hypoxia. PMID:26605339

  19. Effects of nicardipine and nisoldipine on myocardial metabolism, coronary blood flow and oxygen supply in angina pectoris.

    PubMed

    Rousseau, M F; Vincent, M F; Van Hoof, F; Van den Berghe, G; Charlier, A A; Pouleur, H

    1984-12-01

    The effects of the calcium antagonists nicardipine and nisoldipine on left ventricular (LV) metabolism were analyzed in 32 patients with angina pectoris. Measurements were made at a fixed heart rate under the basal state and during a cold pressor test (CPT). After administration of the drugs, coronary blood flow increased significantly and the mean aortic pressure decreased by 10% (p less than 0.01) in the basal state and by 11% (p less than 0.01) during CPT. Despite the reduction in pressure-rate product, myocardial oxygen consumption was unchanged in the basal state (18 +/- 4 vs 19 +/- 4 ml/min, difference not significant) and during CPT (21 +/- 5 vs 21 +/- 5 ml/min, difference not significant); this discrepancy between a reduced pressure-rate product and an unchanged oxygen consumption was also noted when nicardipine was given after propranolol (0.1 mg/kg; 12 patients). Both agents also increased LV lactate uptake, particularly during CPT (+13 mumol/min, p less than 0.05 vs control CPT) and reduced LV glutamine production. In 10 patients in whom 14C-lactate was infused, the chemical LV lactate extraction ratio increased more than the 14C-lactate extraction ratio after administration of the drugs, indicating a reduction in LV lactate production. The data are consistent with the hypothesis that nicardipine and nisoldipine improve perfusion and aerobic metabolism in chronically ischemic areas, resulting in an augmented oxygen consumption and in a reduced lactate production.

  20. In vivo spectral and fluorescence imaging microscopy of tumor microvessel blood supply and oxygenation changes following vascular targeting agent treatment

    NASA Astrophysics Data System (ADS)

    Lee, Jennifer; Kozikowski, Raymond; Molnar, Nikolett; Siemann, Dietmar W.; Sorg, Brian S.

    2012-03-01

    The formation of new microvasculature is essential for a tumor mass to grow. Vascular targeting agents (VTAs), including anti-angiogenic drugs and vascular disrupting agents, aim to either inhibit new vasculature growth or destroy existing vasculature, respectively. Because the mechanisms for anti-angiogenic drugs and vascular disrupting agents are complementary, analysis of these drugs used together is under investigation for the enhanced treatment of tumors in comparison to each treatment alone. The preclinical evaluation of the effects of VTAs on tumor growth in small animal models is vital for the development of effective drugs for clinical use. In vivo hyperspectral imaging microscopy of hemoglobin saturation has been used previously to investigate the efficacy of VTAs through analysis of tumor microvessel oxygenation after drug administration. Combining this imaging modality with first-pass fluorescence angiographic imaging can give additional important information about the vessel morphology and blood flow changes that occur after VTA treatment, thus elucidating the relationship between microvessel structure changes and oxygenation. In this study, we report the combined use of hyperspectral and first pass fluorescence angiographic imaging to examine the relationship between vessel morphology and oxygenation of human prostate cancer tumors in mice following treatment with vascular disrupting agents, OXi4503, and anti-VEGF angiogenesis inhibitor, cediranib. Imaging of the tumors is completed before treatment as well as in the days following treatment.

  1. Retinal oxygen extraction in humans

    NASA Astrophysics Data System (ADS)

    Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

    2015-10-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy.

  2. Retinal oxygen extraction in humans

    PubMed Central

    Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

    2015-01-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy. PMID:26503332

  3. Pilot-Scale Demonstration of a Novel, Low-Cost Oxygen Supply Process and its Integration with Oxy-Fuel Coal-Fired Boilers

    SciTech Connect

    Krish Krishnamurthy; Divy Acharya; Frank Fitch

    2008-09-30

    In order to achieve DOE targets for carbon dioxide capture, it is crucial not only to develop process options that will generate and provide oxygen to the power cycle in a cost-effective manner compared to the conventional oxygen supply methods based on cryogenic air separation technology, but also to identify effective integration options for these new technologies into the power cycle with carbon dioxide capture. The Linde/BOC developed Ceramic Autothermal Recovery (CAR) process remains an interesting candidate to address both of these issues by the transfer of oxygen from the air to a recycled CO{sub 2} rich flue-gas stream in a cyclic process utilizing the high temperature sorption properties of perovskites. Good progress was made on this technology in this project, but significant challenges remain to be addressed before CAR oxygen production technology is ready for commercial exploitation. Phase 1 of the project was completed by the end of September 2008. The two-bed 0.7 tons/day O2 CAR process development unit (PDU) was installed adjacent to WRI's pilot scale coal combustion test facility (CTF). Start-up and operating sequences for the PDU were developed and cyclic operation of the CAR process demonstrated. Controlled low concentration methane addition allowed the beds to be heated up to operational temperature (800-900 C) and then held there during cyclic operation of the 2-bed CAR process, in this way overcoming unavoidable heat losses from the beds during steady state operation. The performance of the PDU was optimized as much as possible, but equipment limitations prevented the system from fully achieving its target performance. Design of the flue gas recirculation system to integrate CAR PDU with the CTF and the system was completed and integrated tests successfully performed at the end of the period. A detailed techno-economic analysis was made of the CAR process for supplying the oxygen in oxy-fuel combustion retrofit option using AEP's 450 MW

  4. Venous oxygen saturation.

    PubMed

    Hartog, Christiane; Bloos, Frank

    2014-12-01

    Early detection and rapid treatment of tissue hypoxia are important goals. Venous oxygen saturation is an indirect index of global oxygen supply-to-demand ratio. Central venous oxygen saturation (ScvO2) measurement has become a surrogate for mixed venous oxygen saturation (SvO2). ScvO2 is measured by a catheter placed in the superior vena cava. After results from a single-center study suggested that maintaining ScvO2 values >70% might improve survival rates in septic patients, international practice guidelines included this target in a bundle strategy to treat early sepsis. However, a recent multicenter study with >1500 patients found that the use of central hemodynamic and ScvO2 monitoring did not improve long-term survival when compared to the clinical assessment of the adequacy of circulation. It seems that if sepsis is recognized early, a rapid initiation of antibiotics and adequate fluid resuscitation are more important than measuring venous oxygen saturation.

  5. 21 CFR 1404.900 - Adequate evidence.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient...

  6. 21 CFR 1404.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Adequate evidence. 1404.900 Section 1404.900 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.900 Adequate evidence. Adequate evidence means information sufficient...

  7. Stem Photosynthesis not Pressurized Ventilation is Responsible for Light-enhanced Oxygen Supply to Submerged Roots of Alder (Alnus glutinosa)

    PubMed Central

    ARMSTRONG, WILLIAM; ARMSTRONG, JEAN

    2005-01-01

    • Background and Aims Claims that submerged roots of alder and other wetland trees are aerated by pressurized gas flow generated in the stem by a light-induced thermo-osmosis have seemed inconsistent with root anatomy. Our aim was to seek a verification using physical root–stem models, stem segments with or without artificial roots, and rooted saplings. • Methods Radial O2 loss (ROL) from roots was monitored polarographically as the gas space system of the models, and stems were pressurized artificially. ROL and internal pressurization were also measured when stems were irradiated and the xylem stream was either CO2 enriched or not. Stem photosynthesis and respiration were measured polarographically. Stem and root anatomy were examined by light and fluorescence microscopy. • Key Results Pressurizing the models and stems to ≤10 kPa, values much higher than those reportedly generated by thermo-osmosis, created only a negligible density-induced increase in ROL, but ROL increased rapidly when ambient O2 concentrations were raised. Internal pressures rose by several kPa when shoots were exposed to high light flux and ROL increased substantially, but both were due to O2 accumulation from stem photosynthesis using internally sourced CO2. Increased stem pressures had little effect on O2 transport, which remained largely diffusive. Oxygen flux from stems in high light periods indicated a net C gain by stem photosynthesis. Chloroplasts were abundant in the secondary cortex and secondary phloem, and occurred throughout the secondary xylem rays and medulla of 3-year-old stems. Diurnal patterns of ROL, most marked when light reached submerged portions of the stem, were modified by minor variations in light flux and water level. Low root temperatures also helped improve root aeration. • Conclusions Pressurized gas flow to submerged roots does not occur to any significant degree in alder, but stem photosynthesis, using internally sourced CO2 from respiration and the

  8. Metabolic adaptation to a disruption in oxygen supply during myocardial ischemia and reperfusion is underpinned by temporal and quantitative changes in the cardiac proteome.

    PubMed

    Li, Xin; Arslan, Fatih; Ren, Yan; Adav, Sunil S; Poh, Kian Keong; Sorokin, Vitaly; Lee, Chuen Neng; de Kleijn, Dominique; Lim, Sai Kiang; Sze, Siu Kwan

    2012-04-06

    Despite decades of intensive research, there is still no effective treatment for ischemia/reperfusion (I/R) injury, an important corollary in the treatment of ischemic disease. I/R injury is initiated when the altered biochemistry of cells after ischemia is no longer compatible with oxygenated microenvironment (or reperfusion). To better understand the molecular basis of this alteration and subsequent incompatibility, we assessed the temporal and quantitative alterations in the cardiac proteome of a mouse cardiac I/R model by an iTRAQ approach at 30 min of ischemia, and at 60 or 120 min reperfusion after the ischemia using sham-operated mouse heart as the baseline control. Of the 509 quantified proteins identified, 121 proteins exhibited significant changes (p-value<0.05) over time and were mostly clustered in eight functional groups: Fatty acid oxidation, Glycolysis, TCA cycle, ETC (electron transport chain), Redox Homeostasis, Glutathione S-transferase, Apoptosis related, and Heat Shock proteins. The first four groups are intimately involved in ATP production and the last four groups are known to be important in cellular antioxidant activity. During ischemia and reperfusion, the short supply of oxygen precipitates a pivotal metabolic switch from aerobic metabolism involving fatty acid oxidation, TCA, and phosphorylation to anaerobic metabolism for ATP production and this, in turn, increases reactive oxygen species (ROS) formation. Therefore the implication of these 8 functional groups suggested that ischemia-reperfusion injury is underpinned in part by proteomic alterations. Reversion of these alterations to preischemia levels took at least 60 min, suggesting a refractory period in which the ischemic cells cannot adjust to the presence of oxygen. Therefore, therapeutics that could compensate for these proteomic alterations during this interim refractory period could alleviate ischemia-reperfusion injury to enhance cellular recovery from an ischemic to a normoxic

  9. NADPH-dependent reductive biotransformation with Escherichia coli and its pfkA deletion mutant: influence on global gene expression and role of oxygen supply.

    PubMed

    Siedler, Solvej; Bringer, Stephanie; Polen, Tino; Bott, Michael

    2014-10-01

    An Escherichia coli ΔpfkA mutant lacking the major phosphofructokinase possesses a partially cyclized pentose phosphate pathway leading to an increased NADPH per glucose ratio. This effect decreases the amount of glucose required for NADPH regeneration in reductive biotransformations, such as the conversion of methyl acetoacetate (MAA) to (R)-methyl 3-hydroxybutyrate (MHB) by an alcohol dehydrogenase from Lactobacillus brevis. Here, global transcriptional analyses were performed to study regulatory responses during reductive biotransformation. DNA microarray analysis revealed amongst other things increased expression of soxS, supporting previous results indicating that a high NADPH demand contributes to the activation of SoxR, the transcriptional activator of soxS. Furthermore, several target genes of the ArcAB two-component system showed a lower mRNA level in the reference strain than in the ΔpfkA mutant, pointing to an increased QH2 /Q ratio in the reference strain. This prompted us to analyze yields and productivities of MAA reduction to MHB under different oxygen regimes in a bioreactor. Under anaerobic conditions, the specific MHB production rates of both strains were comparable (7.4 ± 0.2 mmolMHB  h(-1)  gcdw (-1) ) and lower than under conditions of 15% dissolved oxygen, where those of the reference strain (12.8 mmol h(-1)  gcdw (-1) ) and of the ΔpfkA mutant (11.0 mmol h(-1)  gcdw (-1) ) were 73% and 49% higher. While the oxygen transfer rate (OTR) of the reference strain increased after the addition of MAA, presumably due to the oxidation of the acetate accumulated before MAA addition, the OTR of the ΔpfkA strain strongly decreased, indicating a very low respiration rate despite sufficient oxygen supply. The latter effect can likely be attributed to a restricted conversion of NADPH into NADH via the soluble transhydrogenase SthA, as the enzyme is outcompeted in the presence of MAA by the recombinant NADPH-dependent alcohol

  10. Microbial community and population dynamics of single-stage autotrophic nitrogen removal for dilute wastewater at the benchmark oxygen rate supply.

    PubMed

    Huang, Yu-Tzu; Chen, Shiou-Shiou; Lee, Po-Heng; Bae, Jaeho

    2013-11-01

    Microbial communities and their kinetic performance in a single-stage autotrophic nitrogen-removal filter at an optimal oxygen supply were examined to determine the presence and activity of denitrifiers, anaerobic ammonia-oxidizing (anammox), ammonia-oxidizing, and nitrite-oxidizing bacteria. To this end, different molecular biology techniques such as real-time quantitative polymerase chain reaction (qPCR) and biomarkers such as 16S rRNA revealed a diverse microbial community along the filter. It was important to survey the specific species of anammox bacteria using a newly designed Candidatus Brocadiafulgida (BF) specific primer, as well as Candidatus Brocadia anammoxidans (BA) and Candidatus Kuenenia stuttgartiensis (KS) specific primers. An unexpected finding was that the predominant anammox species switched from KS in concentrated wastewater to BA in dilute wastewaters. The Eckenfelder model of the NH3-N transformation along the filter was Se=S0 exp(-0.192D/L(2.3217)). These results provide a foundational understanding of the microbial structure and reaction kinetics in such systems.

  11. Oxygen boost pump study

    NASA Technical Reports Server (NTRS)

    1975-01-01

    An oxygen boost pump is described which can be used to charge the high pressure oxygen tank in the extravehicular activity equipment from spacecraft supply. The only interface with the spacecraft is the +06 6.205 Pa supply line. The breadboard study results and oxygen tank survey are summarized and the results of the flight-type prototype design and analysis are presented.

  12. 5 CFR 919.900 - Adequate evidence.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Adequate evidence. 919.900 Section 919.900 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.900 Adequate...

  13. [The influence of the products prepared from young not ossified antlers marals of siberian red deer on the characteristics of the blood oxygen-supplying system in the athletes during the contest season].

    PubMed

    Zaĭtsev, A A; Barabash, L V; Smirnova, I N; Abdulkina, N G; Kremeno, S V; Naumov, A O; Vereshchagina, S V; Shteĭnerdt, S V

    2012-01-01

    The objective of the present study was to estimate the influence of the products prepared from young not ossified antlers marals of Siberian red deer on the characteristics of the blood oxygen-supplying system in the athletes undergoing heavy physical loads during the contest season. It was shown that the use of such preparations promotes correction of humoral characteristics reflecting the development of iron-deficient conditions.

  14. Asbestos/NESHAP adequately wet guidance

    SciTech Connect

    Shafer, R.; Throwe, S.; Salgado, O.; Garlow, C.; Hoerath, E.

    1990-12-01

    The Asbestos NESHAP requires facility owners and/or operators involved in demolition and renovation activities to control emissions of particulate asbestos to the outside air because no safe concentration of airborne asbestos has ever been established. The primary method used to control asbestos emissions is to adequately wet the Asbestos Containing Material (ACM) with a wetting agent prior to, during and after demolition/renovation activities. The purpose of the document is to provide guidance to asbestos inspectors and the regulated community on how to determine if friable ACM is adequately wet as required by the Asbestos NESHAP.

  15. Retinal oxygen distribution and the role of neuroglobin.

    PubMed

    Roberts, Paul A; Gaffney, Eamonn A; Luthert, Philip J; Foss, Alexander J E; Byrne, Helen M

    2016-07-01

    The retina is the tissue layer at the back of the eye that is responsible for light detection. Whilst equipped with a rich supply of oxygen, it has one of the highest oxygen demands of any tissue in the body and, as such, supply and demand are finely balanced. It has been suggested that the protein neuroglobin (Ngb), which is found in high concentrations within the retina, may help to maintain an adequate supply of oxygen via the processes of transport and storage. We construct mathematical models, formulated as systems of reaction-diffusion equations in one-dimension, to test this hypothesis. Numerical simulations show that Ngb may play an important role in oxygen transport, but not in storage. Our models predict that the retina is most susceptible to hypoxia in the regions of the photoreceptor inner segment and inner plexiform layers, where Ngb has the potential to prevent hypoxia and increase oxygen uptake by 30-40 %. Analysis of a simplified model confirms the utility of Ngb in transport and shows that its oxygen affinity ([Formula: see text] value) is near optimal for this process. Lastly, asymptotic analysis enables us to identify conditions under which the piecewise linear and quadratic approximations to the retinal oxygen profile, used in the literature, are valid.

  16. Funding the Formula Adequately in Oklahoma

    ERIC Educational Resources Information Center

    Hancock, Kenneth

    2015-01-01

    This report is a longevity, simulational study that looks at how the ratio of state support to local support effects the number of school districts that breaks the common school's funding formula which in turns effects the equity of distribution to the common schools. After nearly two decades of adequately supporting the funding formula, Oklahoma…

  17. Supply and Demand

    MedlinePlus

    ... breast to continue producing an adequate supply of milk. In fact, the protein contained in the residual milk remaining in the ... or fluid) content, and the composition of your milk will change. Over the next week or so, the protein content will decline and the fat and lactose ...

  18. Improving the production yield and productivity of 1,3-dihydroxyacetone from glycerol fermentation using Gluconobacter oxydans NL71 in a compressed oxygen supply-sealed and stirred tank reactor (COS-SSTR).

    PubMed

    Zhou, Xin; Zhou, Xuelian; Xu, Yong; Yu, Shiyuan

    2016-08-01

    In this study, a compressed oxygen gas supply was connected to a sealed aerated stirred tank reactor (COS-SSTR) bio-system, leading to a high-oxygen pressure bioreactor used to improve the bio-transformative performance in the production of 1,3-dihydroxyacetone (DHA) from glycerol using Gluconobacter oxydans NL71. A concentration of 301.2 ± 8.2 g L(-1) DHA was obtained from glycerol after 32 h of fed-batch fermentation in the COS-SSTR system. The volumetric productivity for this process was 9.41 ± 0.23 g L(-1) h(-1), which is presently the highest obtained level of glycerol bioconversion into DHA. These results show that the application of this bioreactor would enable microbial production of DHA from glycerol at the industrial scale.

  19. Solid state oxygen sensor

    DOEpatents

    Garzon, F.H.; Chung, B.W.; Raistrick, I.D.; Brosha, E.L.

    1996-08-06

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer. 4 figs.

  20. Solid state oxygen sensor

    DOEpatents

    Garzon, Fernando H.; Chung, Brandon W.; Raistrick, Ian D.; Brosha, Eric L.

    1996-01-01

    Solid state oxygen sensors are provided with a yttria-doped zirconia as an electrolyte and use the electrochemical oxygen pumping of the zirconia electrolyte. A linear relationship between oxygen concentration and the voltage arising at a current plateau occurs when oxygen accessing the electrolyte is limited by a diffusion barrier. A diffusion barrier is formed herein with a mixed electronic and oxygen ion-conducting membrane of lanthanum-containing perovskite or zirconia-containing fluorite. A heater may be used to maintain an adequate oxygen diffusion coefficient in the mixed conducting layer.

  1. What happens to plant mitochondria under low oxygen? An omics review of the responses to low oxygen and reoxygenation.

    PubMed

    Shingaki-Wells, Rachel; Millar, A Harvey; Whelan, James; Narsai, Reena

    2014-10-01

    Floods can rapidly submerge plants, limiting oxygen to the extent that oxidative phosphorylation no longer generates adequate ATP supplies. Low-oxygen tolerant plants, such as rice, are able to adequately respond to low oxygen by successfully remodelling primary and mitochondrial metabolism to partially counteract the energy crisis that ensues. In this review, we discuss how plants respond to low-oxygen stress at the transcriptomic, proteomic, metabolomic and enzyme activity levels, particularly focusing on mitochondria and interacting pathways. The role of reactive oxygen species and nitrite as an alternative electron acceptor as well as their links to respiratory chain components is discussed. By making intra-kingdom as well as cross-kingdom comparisons, conserved mechanisms of anoxia tolerance are highlighted as well as tolerance mechanisms that are specific to anoxia-tolerant rice during germination and in coleoptiles. We discuss reoxygenation as an often overlooked, yet essential stage of this environmental stress and consider the possibility that changes occurring during low oxygen may also provide benefits upon re-aeration. Finally, we consider what it takes to be low-oxygen tolerant and argue that alternative mechanisms of ATP production, glucose signalling, starch/sucrose signalling as well as reverse metabolism of fermentation end products promote the survival of rice after this debilitating stress.

  2. Oxygen supply to the fetal cerebral circulation in hypoplastic left heart syndrome: a simulation study based on the theoretical models of fetal circulation.

    PubMed

    Sakazaki, Sayaka; Masutani, Satoshi; Sugimoto, Masaya; Tamura, Masanori; Kuwata, Seiko; Kurishima, Clara; Saiki, Hirofumi; Iwamoto, Yoichi; Ishido, Hirotaka; Senzaki, Hideaki

    2015-03-01

    Hypoxia due to congenital heart diseases (CHDs) adversely affects brain development during the fetal period. Head circumference at birth is closely associated with neuropsychiatric development, and it is considerably smaller in newborns with hypoplastic left heart syndrome (HLHS) than in normal newborns. We performed simulation studies on newborns with CHD to evaluate the cerebral circulation during the fetal period. The oxygen saturation of cerebral blood flow in newborns with CHD was simulated according to a model for normal fetal circulation in late pregnancy. We compared the oxygen saturation of cerebral blood flow between newborns with tricuspid atresia (TA; a disease showing univentricular circulation and hypoplasia of the right ventricle), those with transposition of the great arteries (TGA; a disease showing abnormal mixing of arterial and venous blood), and those with HLHS. The oxygen saturation of cerebral blood flow in newborns with normal circulation was 75.7 %, whereas it was low (49.5 %) in both newborns with HLHS and those with TA. Although the oxygen level is affected by the blood flow through the foramen ovale, the oxygen saturation in newborns with TGA was even lower (43.2 %). These data, together with previous reports, suggest that the cerebral blood flow rate is decreased in newborns with HLHS, and the main cause was strongly suspected to be retrograde cerebral perfusion through a patent ductus arteriosus. This study provides important information about the neurodevelopmental prognosis of newborns with HLHS and suggests the need to identify strategies to resolve this unfavorable cerebral circulatory state in utero.

  3. Oxygen transport through soft contact lens and cornea: Lens characterization and metabolic modeling

    NASA Astrophysics Data System (ADS)

    Chhabra, Mahendra

    The human cornea requires oxygen to sustain metabolic processes critical for its normal functioning. Any restriction to corneal oxygen supply from the external environment (e.g., by wearing a low oxygen-permeability contact lens) can lead to hypoxia, which may cause corneal edema (swelling), limbal hyperemia, neovascularization, and corneal acidosis. The need for adequate oxygen to the cornea is a major driving force for research and development of hypertransmissible soft contact lenses (SCLs). Currently, there is no standard technique for measuring oxygen permeability (Dk) of hypertransmissible silicone-hydrogel SCLs. In this work, an electrochemistry-based polarographic apparatus was designed, built, and operated to measure oxygen permeability in hypertransmissible SCLs. Unlike conventional methods where a range of lens thickness is needed for determining oxygen permeabilities of SCLs, this apparatus requires only a single lens thickness. The single-lens permeameter provides a reliable, efficient, and economic tool for measuring oxygen permeabilities of commercial hypertransmissible SCLs. The single-lens permeameter measures not only the product Dk, but, following modification, it measures separately diffusivity, D, and solubility, k, of oxygen in hypertransmissible SCLs. These properties are critical for designing better lens materials that ensure sufficient oxygen supply to the cornea. Metabolism of oxygen in the cornea is influenced by contact-lens-induced hypoxia, diseases such as diabetes, surgery, and drug treatment, Thus, estimation of the in-vivo corneal oxygen consumption rate is essential for gauging adequate oxygen supply to the cornea. Therefore, we have developed an unsteady-state reactive-diffusion model for the cornea-contact-lens system to determine in-vivo human corneal oxygen-consumption rate. Finally, a metabolic model was developed to determine the relation between contact-lens oxygen transmissibility (Dk/L) and corneal oxygen deficiency. A

  4. Serum thyroglobulin reference intervals in regions with adequate and more than adequate iodine intake.

    PubMed

    Wang, Zhaojun; Zhang, Hanyi; Zhang, Xiaowen; Sun, Jie; Han, Cheng; Li, Chenyan; Li, Yongze; Teng, Xiaochun; Fan, Chenling; Liu, Aihua; Shan, Zhongyan; Liu, Chao; Weng, Jianping; Teng, Weiping

    2016-11-01

    The purpose of this study was to establish normal thyroglobulin (Tg) reference intervals (RIs) in regions with adequate and more than adequate iodine intake according to the National Academy of Clinical Biochemistry (NACB) guidelines and to investigate the relationships between Tg and other factors.A total of 1317 thyroid disease-free adult subjects (578 men, 739 nonpregnant women) from 2 cities (Guangzhou and Nanjing) were enrolled in this retrospective, observational study. Each subject completed a questionnaire and underwent physical and ultrasonic examination. Serum Tg, thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), Tg antibody (TgAb), and urinary iodine concentration (UIC) were measured. Reference groups were established on the basis of TSH levels: 0.5 to 2.0 and 0.27 to 4.2 mIU/L.The Tg RIs for Guangzhou and Nanjing were 1.6 to 30.0 and 1.9 to 25.8 ng/mL, respectively. No significant differences in Tg were found between genders or among different reference groups. Stepwise linear regression analyses showed that TgAb, thyroid volume, goiter, gender, age, and TSH levels were correlated with Tg.In adults from regions with adequate and more than adequate iodine intake, we found that Tg may be a suitable marker of iodine status; gender-specific Tg RI was unnecessary; there was no difference between Tg RIs in regions with adequate and more than adequate iodine intake; and the TSH criterion for selecting the Tg reference population could follow the local TSH reference rather than 0.5 to 2.0 mIU/L.

  5. Serum thyroglobulin reference intervals in regions with adequate and more than adequate iodine intake

    PubMed Central

    Wang, Zhaojun; Zhang, Hanyi; Zhang, Xiaowen; Sun, Jie; Han, Cheng; Li, Chenyan; Li, Yongze; Teng, Xiaochun; Fan, Chenling; Liu, Aihua; Shan, Zhongyan; Liu, Chao; Weng, Jianping; Teng, Weiping

    2016-01-01

    Abstract The purpose of this study was to establish normal thyroglobulin (Tg) reference intervals (RIs) in regions with adequate and more than adequate iodine intake according to the National Academy of Clinical Biochemistry (NACB) guidelines and to investigate the relationships between Tg and other factors. A total of 1317 thyroid disease-free adult subjects (578 men, 739 nonpregnant women) from 2 cities (Guangzhou and Nanjing) were enrolled in this retrospective, observational study. Each subject completed a questionnaire and underwent physical and ultrasonic examination. Serum Tg, thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), Tg antibody (TgAb), and urinary iodine concentration (UIC) were measured. Reference groups were established on the basis of TSH levels: 0.5 to 2.0 and 0.27 to 4.2 mIU/L. The Tg RIs for Guangzhou and Nanjing were 1.6 to 30.0 and 1.9 to 25.8 ng/mL, respectively. No significant differences in Tg were found between genders or among different reference groups. Stepwise linear regression analyses showed that TgAb, thyroid volume, goiter, gender, age, and TSH levels were correlated with Tg. In adults from regions with adequate and more than adequate iodine intake, we found that Tg may be a suitable marker of iodine status; gender-specific Tg RI was unnecessary; there was no difference between Tg RIs in regions with adequate and more than adequate iodine intake; and the TSH criterion for selecting the Tg reference population could follow the local TSH reference rather than 0.5 to 2.0 mIU/L. PMID:27902589

  6. Changes in oxygenation and phosphocreatine during exercise and recovery in relation to fiber types and capillary supply in human skeletal muscle

    NASA Astrophysics Data System (ADS)

    Hamaoka, Takatumi; Mizuno, Masano; Osada, Takuya; Ratkevicius, Aivaras; Nielsen, Alexander N.; Nakagawa, Yoshinao; Katsumura, Toshihito; Shimomitsu, Teruichi; Quistorff, Bjorn

    1997-12-01

    The purpose of this study was to examine the relationship between histochemical characteristics obtained from the gastrocnemius and changes in muscle energetics. Muscle oxygenation was determined by near infrared spectroscopy, and phosphocreatine (PCr) by 31-phosphorus magnetic resonance spectroscopy (31P-MRS) during a submaximal plantar flexion exercise and recovery. The relative occurrence (%) of slow-twitch fibers (ST), fast-twitch oxidative fibers (FTa), fast-twitch glycolytic fibers (FTb), and the number of capillaries per fiber (Cap/Fiber) were also determined. The sum of %ST and %FTa (%ST + %FTa) was 85.8 +/- 8.74% (mean +/- SD), while the number of Cap/Fiber was 2.52 +/- 0.63. The initial rate of deoxygenation (Ratedeoxy) at the beginning of the exercise was 2.43 +/- 0.95 %(DOT)sec-1. The time constants (Tc) for the recovery of PCr and muscle oxygenation after exercise were 22.1 +/- 6.3 sec. and 20.3 +/- 13.6 sec., respectively. The %ST + FTa, and the number of Cap/Fiber were each positively correlated to the Ratedeoxy (P < 0.05). The %ST + %FTa, and the number of Cap/Fiber were negatively correlated to the Tc for PCr recovery (P < 0.05), but not correlated to that for muscle oxygenation recovery. In conclusion, the Ratedeoxy during localized submaximal exercise, and the Tc for PCr recovery are indicators of the muscle's oxidative capacity.

  7. Changes in oxygenation and phosphocreatine during exercise and recovery in relation to fiber types and capillary supply in human skeletal muscle

    NASA Astrophysics Data System (ADS)

    Hamaoka, Takatumi; Mizuno, Masano; Osada, Takuya; Ratkevicius, Aivaras; Nielsen, Alexander N.; Nakagawa, Yoshinao; Katsumura, Toshihito; Shimomitsu, Teruichi; Quistorff, Bjorn

    1998-01-01

    The purpose of this study was to examine the relationship between histochemical characteristics obtained from the gastrocnemius and changes in muscle energetics. Muscle oxygenation was determined by near infrared spectroscopy, and phosphocreatine (PCr) by 31-phosphorus magnetic resonance spectroscopy (31P-MRS) during a submaximal plantar flexion exercise and recovery. The relative occurrence (%) of slow-twitch fibers (ST), fast-twitch oxidative fibers (FTa), fast-twitch glycolytic fibers (FTb), and the number of capillaries per fiber (Cap/Fiber) were also determined. The sum of %ST and %FTa (%ST + %FTa) was 85.8 +/- 8.74% (mean +/- SD), while the number of Cap/Fiber was 2.52 +/- 0.63. The initial rate of deoxygenation (Ratedeoxy) at the beginning of the exercise was 2.43 +/- 0.95 %(DOT)sec-1. The time constants (Tc) for the recovery of PCr and muscle oxygenation after exercise were 22.1 +/- 6.3 sec. and 20.3 +/- 13.6 sec., respectively. The %ST + FTa, and the number of Cap/Fiber were each positively correlated to the Ratedeoxy (P < 0.05). The %ST + %FTa, and the number of Cap/Fiber were negatively correlated to the Tc for PCr recovery (P < 0.05), but not correlated to that for muscle oxygenation recovery. In conclusion, the Ratedeoxy during localized submaximal exercise, and the Tc for PCr recovery are indicators of the muscle's oxidative capacity.

  8. Strategic Supply

    DTIC Science & Technology

    2005-01-01

    the potential to capitalize on more efficient and effective management of their respective supply chains . Supply Chain Management (SCM) is the...transformation efforts have the potential to create a more agile, flexible and resilient supply chain that is responsive to Commanders and sensitive to...optimizing their supply chain to remain viable and create competitive advantage. Supply Chain Management (SCM) is grounded in the field of logistics

  9. The influence of fuel mass load, oxygen supply and burning rate on emission factor and size distribution of carbonaceous particulate matter from indoor corn straw burning

    PubMed Central

    Shen, Guofeng; Xue, Miao; Wei, Siye; Chen, Yuanchen; Wang, Bing; Wang, Rong; Shen, Huizhong; Li, Wei; Zhang, Yanyan; Huang, Ye; Chen, Han; Wei, Wen; Zhao, Qiuyue; Li, Bin; Wu, Haisuo; Tao, Shu

    2014-01-01

    The uncertainty in emission estimation is strongly associated with the variation in emission factor which could be influenced by a variety of factors, like fuel property, stove type, fire management and even methods used in measurements. The impacts of these factors were usually complicated and often interacted with each other. In the present study, controlled burning experiments were conducted to investigate the influence of fuel mass load, air supply and burning rate on the emission of carbonaceous particulate matter (PM) from indoor corn straw burning. Their impacts on PM size distribution were also studied. The results showed that EFs of PM (EFPM), organic carbon (EFOC) and element carbon (EFEC) was independent of the fuel mass load. The differences among them under different burning rates or air supply amounts were also found to be insignificant (p > 0.05) in the tested circumstances. PM from the indoor corn straw burning was dominated by fine PM, and PM with diameter less than 2.1 μm contributed about 86.4±3.9% of the total. The size distribution of PM was also influenced by the burning rate and changed air supply conditions. On average, EFPM, EFOC and EFEC for corn straw burned in a residential cooking stove were 3.84±1.02, 0.846±0.895 and 0.391±0.350 g/kg, respectively. EFPM, EFOC and EFEC were found to be positively correlated with each other, but they were not significantly correlated with EF of co-emitted CO, suggesting a special attention should be paid to the use of CO acting as a surrogate for other incomplete pollutants. PMID:23923424

  10. 20 CFR 654.405 - Water supply.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 3 2013-04-01 2013-04-01 false Water supply. 654.405 Section 654.405... THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.405 Water supply. (a) An adequate and convenient supply of water that meets the standards of the State...

  11. 20 CFR 654.405 - Water supply.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Water supply. 654.405 Section 654.405... THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.405 Water supply. (a) An adequate and convenient supply of water that meets the standards of the State...

  12. 9 CFR 354.224 - Water supply.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Water supply. 354.224 Section 354.224....224 Water supply. The water supply shall be ample, clean, and potable with adequate facilities for its distribution in the plant and its protection against contamination and pollution. (a) Hot water at...

  13. 9 CFR 354.224 - Water supply.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Water supply. 354.224 Section 354.224....224 Water supply. The water supply shall be ample, clean, and potable with adequate facilities for its distribution in the plant and its protection against contamination and pollution. (a) Hot water at...

  14. 20 CFR 654.405 - Water supply.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 3 2014-04-01 2014-04-01 false Water supply. 654.405 Section 654.405... THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.405 Water supply. (a) An adequate and convenient supply of water that meets the standards of the State...

  15. 20 CFR 654.405 - Water supply.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Water supply. 654.405 Section 654.405... THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.405 Water supply. (a) An adequate and convenient supply of water that meets the standards of the State...

  16. 9 CFR 354.224 - Water supply.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Water supply. 354.224 Section 354.224....224 Water supply. The water supply shall be ample, clean, and potable with adequate facilities for its distribution in the plant and its protection against contamination and pollution. (a) Hot water at...

  17. 9 CFR 354.224 - Water supply.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Water supply. 354.224 Section 354.224....224 Water supply. The water supply shall be ample, clean, and potable with adequate facilities for its distribution in the plant and its protection against contamination and pollution. (a) Hot water at...

  18. 20 CFR 654.405 - Water supply.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false Water supply. 654.405 Section 654.405... THE EMPLOYMENT SERVICE SYSTEM Housing for Agricultural Workers Housing Standards § 654.405 Water supply. (a) An adequate and convenient supply of water that meets the standards of the State...

  19. 9 CFR 354.224 - Water supply.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Water supply. 354.224 Section 354.224....224 Water supply. The water supply shall be ample, clean, and potable with adequate facilities for its distribution in the plant and its protection against contamination and pollution. (a) Hot water at...

  20. Adequate mathematical modelling of environmental processes

    NASA Astrophysics Data System (ADS)

    Chashechkin, Yu. D.

    2012-04-01

    In environmental observations and laboratory visualization both large scale flow components like currents, jets, vortices, waves and a fine structure are registered (different examples are given). The conventional mathematical modeling both analytical and numerical is directed mostly on description of energetically important flow components. The role of a fine structures is still remains obscured. A variety of existing models makes it difficult to choose the most adequate and to estimate mutual assessment of their degree of correspondence. The goal of the talk is to give scrutiny analysis of kinematics and dynamics of flows. A difference between the concept of "motion" as transformation of vector space into itself with a distance conservation and the concept of "flow" as displacement and rotation of deformable "fluid particles" is underlined. Basic physical quantities of the flow that are density, momentum, energy (entropy) and admixture concentration are selected as physical parameters defined by the fundamental set which includes differential D'Alembert, Navier-Stokes, Fourier's and/or Fick's equations and closing equation of state. All of them are observable and independent. Calculations of continuous Lie groups shown that only the fundamental set is characterized by the ten-parametric Galilelian groups reflecting based principles of mechanics. Presented analysis demonstrates that conventionally used approximations dramatically change the symmetries of the governing equations sets which leads to their incompatibility or even degeneration. The fundamental set is analyzed taking into account condition of compatibility. A high order of the set indicated on complex structure of complete solutions corresponding to physical structure of real flows. Analytical solutions of a number problems including flows induced by diffusion on topography, generation of the periodic internal waves a compact sources in week-dissipative media as well as numerical solutions of the same

  1. Metabolic dynamics in skeletal muscle during acute reduction in blood flow and oxygen supply to mitochondria: in-silico studies using a multi-scale, top-down integrated model.

    PubMed

    Dash, Ranjan K; Li, Yanjun; Kim, Jaeyeon; Beard, Daniel A; Saidel, Gerald M; Cabrera, Marco E

    2008-09-09

    Control mechanisms of cellular metabolism and energetics in skeletal muscle that may become evident in response to physiological stresses such as reduction in blood flow and oxygen supply to mitochondria can be quantitatively understood using a multi-scale computational model. The analysis of dynamic responses from such a model can provide insights into mechanisms of metabolic regulation that may not be evident from experimental studies. For the purpose, a physiologically-based, multi-scale computational model of skeletal muscle cellular metabolism and energetics was developed to describe dynamic responses of key chemical species and reaction fluxes to muscle ischemia. The model, which incorporates key transport and metabolic processes and subcellular compartmentalization, is based on dynamic mass balances of 30 chemical species in both capillary blood and tissue cells (cytosol and mitochondria) domains. The reaction fluxes in cytosol and mitochondria are expressed in terms of a general phenomenological Michaelis-Menten equation involving the compartmentalized energy controller ratios ATP/ADP and NADH/NAD(+). The unknown transport and reaction parameters in the model are estimated simultaneously by minimizing the differences between available in vivo experimental data on muscle ischemia and corresponding model outputs in coupled with the resting linear flux balance constraints using a robust, nonlinear, constrained-based, reduced gradient optimization algorithm. With the optimal parameter values, the model is able to simulate dynamic responses to reduced blood flow and oxygen supply to mitochondria associated with muscle ischemia of several key metabolite concentrations and metabolic fluxes in the subcellular cytosolic and mitochondrial compartments, some that can be measured and others that can not be measured with the current experimental techniques. The model can be applied to test complex hypotheses involving dynamic regulation of cellular metabolism and

  2. Strategic Supply

    DTIC Science & Technology

    2006-01-01

    context of Supply Chain Management ( SCM ), it is quite apparent that Strategic Supply cannot be classified as a particular industry; but rather, as an...Management ( SCM ), it is quite apparent that Strategic Supply cannot be classified as a particular industry; but rather, as an enabler across all...advantage in the global marketplace. The Council of Supply Chain Management Professionals (CSCMP) has defined SCM as, “…encompassing the planning

  3. Monitoring Cerebral Oxygenation in Neonates: An Update

    PubMed Central

    Dix, Laura Marie Louise; van Bel, Frank; Lemmers, Petra Maria Anna

    2017-01-01

    Cerebral oxygenation is not always reflected by systemic arterial oxygenation. Therefore, regional cerebral oxygen saturation (rScO2) monitoring with near-infrared spectroscopy (NIRS) is of added value in neonatal intensive care. rScO2 represents oxygen supply to the brain, while cerebral fractional tissue oxygen extraction, which is the ratio between rScO2 and systemic arterial oxygen saturation, reflects cerebral oxygen utilization. The balance between oxygen supply and utilization provides insight in neonatal cerebral (patho-)physiology. This review highlights the potential and limitations of cerebral oxygenation monitoring with NIRS in the neonatal intensive care unit. PMID:28352624

  4. Seed Priming Alters the Production and Detoxification of Reactive Oxygen Intermediates in Rice Seedlings Grown under Sub-optimal Temperature and Nutrient Supply.

    PubMed

    Hussain, Saddam; Khan, Fahad; Cao, Weidong; Wu, Lishu; Geng, Mingjian

    2016-01-01

    The production and detoxification of reactive oxygen intermediates (ROIs) play an important role in the plant response to nutrient and environmental stresses. The present study demonstrated the behavior of growth, ROIs-production and their detoxification in primed and non-primed rice seedlings under chilling stress (18°C) and nitrogen-(N), phosphorus-(P), or potassium-(K) deprivation. The results revealed that chilling stress as well as deprivation of any mineral nutrient severely hampered the seedling growth of rice, however, seed priming treatments (particularly selenium- or salicylic acid-priming), were effective in enhancing the rice growth under stress conditions. The N-deprivation caused the maximum reduction in shoot growth, while the root growth was only decreased by P- or K-deprivation. Although, N-deprivation enhanced the root length of rice, the root fresh weight was unaffected. Rate of lipid peroxidation as well as the production of ROIs, was generally increased under stress conditions; the K-deprived seedlings recorded significantly lower production of ROIs than N- or P-deprived seedlings. The responses of enzymatic and non-enzymatic antioxidants in rice seedlings to chilling stress were variable with nutrient management regime. All the seed priming were found to trigger or at least maintain the antioxidant defense system of rice seedlings. Notably, the levels of ROIs were significantly reduced by seed priming treatments, which were concomitant with the activities of ROIs-producing enzymes (monoamine oxidase and xanthine oxidase), under all studied conditions. Based on these findings, we put forward the hypothesis that along with role of ROIs-scavenging enzymes, the greater tolerance of primed rice seedlings can also be due to the reduced activity of ROIs-producing enzymes.

  5. Seed Priming Alters the Production and Detoxification of Reactive Oxygen Intermediates in Rice Seedlings Grown under Sub-optimal Temperature and Nutrient Supply

    PubMed Central

    Hussain, Saddam; Khan, Fahad; Cao, Weidong; Wu, Lishu; Geng, Mingjian

    2016-01-01

    The production and detoxification of reactive oxygen intermediates (ROIs) play an important role in the plant response to nutrient and environmental stresses. The present study demonstrated the behavior of growth, ROIs-production and their detoxification in primed and non-primed rice seedlings under chilling stress (18°C) and nitrogen-(N), phosphorus-(P), or potassium-(K) deprivation. The results revealed that chilling stress as well as deprivation of any mineral nutrient severely hampered the seedling growth of rice, however, seed priming treatments (particularly selenium- or salicylic acid-priming), were effective in enhancing the rice growth under stress conditions. The N-deprivation caused the maximum reduction in shoot growth, while the root growth was only decreased by P- or K-deprivation. Although, N-deprivation enhanced the root length of rice, the root fresh weight was unaffected. Rate of lipid peroxidation as well as the production of ROIs, was generally increased under stress conditions; the K-deprived seedlings recorded significantly lower production of ROIs than N- or P-deprived seedlings. The responses of enzymatic and non-enzymatic antioxidants in rice seedlings to chilling stress were variable with nutrient management regime. All the seed priming were found to trigger or at least maintain the antioxidant defense system of rice seedlings. Notably, the levels of ROIs were significantly reduced by seed priming treatments, which were concomitant with the activities of ROIs-producing enzymes (monoamine oxidase and xanthine oxidase), under all studied conditions. Based on these findings, we put forward the hypothesis that along with role of ROIs-scavenging enzymes, the greater tolerance of primed rice seedlings can also be due to the reduced activity of ROIs-producing enzymes. PMID:27092157

  6. Oxygen exchange in the isolated, arrested guinea pig heart: theoretical and experimental observations.

    PubMed Central

    Mawson, D A; Hunter, P J; Kenwright, D N; Loiselle, D S

    1994-01-01

    A model of oxygen transport in perfused myocardial tissue is presented. Steady-state conditions are assumed in order to mimic the metabolic rate of the arrested heart. The model incorporates Michaelis-Menten dependence of mitochondrial oxygen consumption, oxymyoglobin saturation and oxyhemoglobin saturation on oxygen partial pressure (PO2). The transport equations model both the advective supply of oxygen via the coronary circulation and the diffusive exchange of oxygen between tissues and environment across the epicardial and endocardial surfaces. The left ventricle is approximated by an axisymmetric prolate spheroid and the transport equations solved numerically using finite element techniques. Solution yields the PO2 profile across the heart wall. Integration of this profile yields the simulated rate of metabolic oxygen uptake determined according to the Fick principle. Correction for the diffusive flux of oxygen across the surfaces yields the simulated true metabolic rate of oxygen consumption. Simulated values of oxygen uptake are compared with those measured experimentally according to the Fick principle, using saline-perfused, Langendorff-circulated, K(+)-arrested, guinea pig hearts. Four perfusion variables were manipulated: arterial PO2, environmental PO2, coronary flow and perfusion pressure. In each case agreement between simulated and experimentally determined rates of oxygen consumption gives confidence that the model adequately describes the advective and diffusive transport of oxygen in the isolated, arrested, saline-perfused heart. Images FIGURE A1 PMID:8011911

  7. Image-based modelling of skeletal muscle oxygenation.

    PubMed

    Zeller-Plumhoff, B; Roose, T; Clough, G F; Schneider, P

    2017-02-01

    The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, in particular for skeletal muscle during exercise. Disease is often associated with both an inhibition of the microvascular supply capability and is thought to relate to changes in the structure of blood vessel networks. Different methods exist to investigate the influence of the microvascular structure on tissue oxygenation, varying over a range of application areas, i.e. biological in vivo and in vitro experiments, imaging and mathematical modelling. Ideally, all of these methods should be combined within the same framework in order to fully understand the processes involved. This review discusses the mathematical models of skeletal muscle oxygenation currently available that are based upon images taken of the muscle microvasculature in vivo and ex vivo Imaging systems suitable for capturing the blood vessel networks are discussed and respective contrasting methods presented. The review further informs the association between anatomical characteristics in health and disease. With this review we give the reader a tool to understand and establish the workflow of developing an image-based model of skeletal muscle oxygenation. Finally, we give an outlook for improvements needed for measurements and imaging techniques to adequately investigate the microvascular capability for oxygen exchange.

  8. Image-based modelling of skeletal muscle oxygenation

    PubMed Central

    Clough, G. F.

    2017-01-01

    The supply of oxygen in sufficient quantity is vital for the correct functioning of all organs in the human body, in particular for skeletal muscle during exercise. Disease is often associated with both an inhibition of the microvascular supply capability and is thought to relate to changes in the structure of blood vessel networks. Different methods exist to investigate the influence of the microvascular structure on tissue oxygenation, varying over a range of application areas, i.e. biological in vivo and in vitro experiments, imaging and mathematical modelling. Ideally, all of these methods should be combined within the same framework in order to fully understand the processes involved. This review discusses the mathematical models of skeletal muscle oxygenation currently available that are based upon images taken of the muscle microvasculature in vivo and ex vivo. Imaging systems suitable for capturing the blood vessel networks are discussed and respective contrasting methods presented. The review further informs the association between anatomical characteristics in health and disease. With this review we give the reader a tool to understand and establish the workflow of developing an image-based model of skeletal muscle oxygenation. Finally, we give an outlook for improvements needed for measurements and imaging techniques to adequately investigate the microvascular capability for oxygen exchange. PMID:28202595

  9. Fluorescence-lifetime-based sensors: oxygen sensing and other biomedical applications

    NASA Astrophysics Data System (ADS)

    Randers-Eichhorn, Lisa; Bartlett, Roscoe A.; Sipior, Jeffrey; Frey, Douglas D.; Carter, Gary M.; Lakowicz, Joseph R.; Rao, Govind

    1996-05-01

    Murine hybridomas were cultivated in tissue culture flasks. Dissolved oxygen tensions in the gas and liquid phases during cell growth were measured non-invasively by an optical oxygen sensor. Readings were made with caps both cracked open and completely closed. During cell growth, gas phase oxygen concentrations remained near atmospheric levels, while the oxygen tension at the bottom of the flasks eventually reached zero. These results suggest that the widespread practice of cracking open tissue culture flask caps during cell growth with a view to supplying adequate oxygen to cells is ineffective and unnecessary. The mass transfer characteristics of the tissue culture flask indicate the dominant resistance to oxygen mass transfer to the cells was the liquid media. The mass transfer rates through the liquid layer under standard laboratory conditions were found to be greater than those predicted by diffusion alone, suggesting microscale mixing. Volumetric and specific oxygen consumption rates were calculated from the sensor data, and were comparable to published values. A recently developed single fiber optic oxygen sensor is described. This new sensor will provide oxygen concentrations at various levels in the tissue culture flasks, allowing more accurate modeling of oxygen diffusion.

  10. Food and water supply

    NASA Technical Reports Server (NTRS)

    Popov, I. G.

    1975-01-01

    Supplying astronauts with adequate food and water on short and long-term space flights is discussed based on experiences gained in space flight. Food consumption, energy requirements, and suitability of the foodstuffs for space flight are among the factors considered. Physicochemical and biological methods of food production and regeneration of water from astronaut metabolic wastes, as well as wastes produced in a closed ecological system, or as a result of technical processes taking place in various spacecraft systems are suggested for long-term space flights.

  11. School Nurse Inspections Improve Handwashing Supplies

    ERIC Educational Resources Information Center

    Ramos, Mary M.; Schrader, Ronald; Trujillo, Rebecca; Blea, Mary; Greenberg, Cynthia

    2011-01-01

    Background: Handwashing in the school setting is important for infectious disease control, yet maintaining adequate handwashing supplies is often made difficult by lack of funds, limited staff time, and student vandalism. This study measured the availability of handwashing supplies for students in New Mexico public schools and determined the…

  12. Nursing Supplies

    MedlinePlus

    ... Stages Listen Español Text Size Email Print Share Nursing Supplies Page Content Article Body Throughout most of ... budget. (Nursing equipment also makes wonderful baby gifts.) Nursing Bras A well-made nursing bra that comfortably ...

  13. Modelling the effects of cerebral microvasculature morphology on oxygen transport.

    PubMed

    Park, Chang Sub; Payne, Stephen J

    2016-01-01

    The cerebral microvasculature plays a vital role in adequately supplying blood to the brain. Determining the health of the cerebral microvasculature is important during pathological conditions, such as stroke and dementia. Recent studies have shown the complex relationship between cerebral metabolic rate and transit time distribution, the transit times of all the possible pathways available dependent on network topology. In this paper, we extend a recently developed technique to solve for residue function, the amount of tracer left in the vasculature at any time, and transit time distribution in an existing model of the cerebral microvasculature to calculate cerebral metabolism. We present the mathematical theory needed to solve for oxygen concentration followed by results of the simulations. It is found that oxygen extraction fraction, the fraction of oxygen removed from the blood in the capillary network by the tissue, and cerebral metabolic rate are dependent on both mean and heterogeneity of the transit time distribution. For changes in cerebral blood flow, a positive correlation can be observed between mean transit time and oxygen extraction fraction, and a negative correlation between mean transit time and metabolic rate of oxygen. A negative correlation can also be observed between transit time heterogeneity and the metabolic rate of oxygen for a constant cerebral blood flow. A sensitivity analysis on the mean and heterogeneity of the transit time distribution was able to quantify their respective contributions to oxygen extraction fraction and metabolic rate of oxygen. Mean transit time has a greater contribution than the heterogeneity for oxygen extraction fraction. This is found to be opposite for metabolic rate of oxygen. These results provide information on the role of the cerebral microvasculature and its effects on flow and metabolism. They thus open up the possibility of obtaining additional valuable clinical information for diagnosing and treating

  14. The oxygen supply to thermogenic flowers.

    PubMed

    Seymour, Roger S; Ito, Kikukatsu; Umekawa, Yui; Matthews, Philip D G; Pirintsos, Stergios Arg

    2015-04-01

    Thermogenic flowers produce heat by intense respiration, and the rates of O2 consumption (Ṁo2) in some species can exceed those of all other tissues of plants and most animals. By exposing intact flowers to a range of O2 pressures (Po2) and measuring Ṁo2, we demonstrate that the highest respiration rates exceed the capacity of the O2 diffusive pathway and become diffusion limited in atmospheric air. The male florets on the inflorescence of Arum concinnatum have the highest known mass-specific Ṁo2 and can be severely diffusion limited. Intact spadices of Japanese skunk cabbage Symplocarpus renifolius are diffusion limited in air only when Ṁo2 is maximal, but not at lower levels. True flowers of the sacred lotus Nelumbo nucifera and the appendix of Arum concinnatum are never diffusion limited in air. Ṁo2 - Po2 curves are evaluated quantitatively with the 'Regulation Index', a new tool to measure dependence of Ṁo2 on ambient Po2 , as well as the conventional 'Critical Po2 '. The study also includes measurements of Po2 within thermogenic tissues with O2-sensitive fibre optics, and reveals that the diffusion pathway is complicated and that O2 can be provided not only from the surface of the tissues but also from the pith of the flower's peduncle.

  15. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Adequate file search. 716.25 Section 716.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of...

  16. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Adequate file search. 716.25 Section 716.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of...

  17. "Something Adequate"? In Memoriam Seamus Heaney, Sister Quinlan, Nirbhaya

    ERIC Educational Resources Information Center

    Parker, Jan

    2014-01-01

    Seamus Heaney talked of poetry's responsibility to represent the "bloody miracle", the "terrible beauty" of atrocity; to create "something adequate". This article asks, what is adequate to the burning and eating of a nun and the murderous gang rape and evisceration of a medical student? It considers Njabulo Ndebele's…

  18. 40 CFR 716.25 - Adequate file search.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Adequate file search. 716.25 Section... ACT HEALTH AND SAFETY DATA REPORTING General Provisions § 716.25 Adequate file search. The scope of a person's responsibility to search records is limited to records in the location(s) where the...

  19. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  20. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  1. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  2. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  3. 40 CFR 51.354 - Adequate tools and resources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Adequate tools and resources. 51.354... Requirements § 51.354 Adequate tools and resources. (a) Administrative resources. The program shall maintain the administrative resources necessary to perform all of the program functions including...

  4. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  5. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  6. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  7. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  8. 9 CFR 305.3 - Sanitation and adequate facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Sanitation and adequate facilities. 305.3 Section 305.3 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... OF VIOLATION § 305.3 Sanitation and adequate facilities. Inspection shall not be inaugurated if...

  9. 21 CFR 201.5 - Drugs; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Drugs; adequate directions for use. 201.5 Section 201.5 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL LABELING General Labeling Provisions § 201.5 Drugs; adequate directions for use....

  10. Monolithic solid electrolyte oxygen pump

    DOEpatents

    Fee, Darrell C.; Poeppel, Roger B.; Easler, Timothy E.; Dees, Dennis W.

    1989-01-01

    A multi-layer oxygen pump having a one-piece, monolithic ceramic structure affords high oxygen production per unit weight and volume and is thus particularly adapted for use as a portable oxygen supply. The oxygen pump is comprised of a large number of small cells on the order of 1-2 millimeters in diameter which form the walls of the pump and which are comprised of thin, i.e., 25-50 micrometers, ceramic layers of cell components. The cell components include an air electrode, an oxygen electrode, an electrolyte and interconnection materials. The cell walls form the passages for input air and for exhausting the oxygen which is transferred from a relatively dilute gaseous mixture to a higher concentration by applying a DC voltage across the electrodes so as to ionize the oxygen at the air electrode, whereupon the ionized oxygen travels through the electrolyte and is converted to oxygen gas at the oxygen electrode.

  11. Information flow in the pharmaceutical supply chain.

    PubMed

    Yousefi, Nazila; Alibabaei, Ahmad

    2015-01-01

    Managing the supply chain plays an important role in creating competitive advantages for companies. Adequate information flow in supply chain is one of the most important issues in SCM. Therefore, using certain Information Systems can have a significant role in managing and integrating data and information within the supply chain. Pharmaceutical supply chain is more complex than many other supply chains, in the sense that it can affect social and political perspectives. On the other hand, managing the pharmaceutical supply chain is difficult because of its complexity and also government regulations in this field. Although, Iran has progressed a lot in pharmaceutical manufacturing, still there are many unsolved issues in managing the information flow in the pharmaceutical supply chain. In this study, we reviewed the benefits of using different levels of an integrated information system in the supply chain and the possible challenges ahead.

  12. Information flow in the pharmaceutical supply chain

    PubMed Central

    Yousefi, Nazila; Alibabaei, Ahmad

    2015-01-01

    Managing the supply chain plays an important role in creating competitive advantages for companies. Adequate information flow in supply chain is one of the most important issues in SCM. Therefore, using certain Information Systems can have a significant role in managing and integrating data and information within the supply chain. Pharmaceutical supply chain is more complex than many other supply chains, in the sense that it can affect social and political perspectives. On the other hand, managing the pharmaceutical supply chain is difficult because of its complexity and also government regulations in this field. Although, Iran has progressed a lot in pharmaceutical manufacturing, still there are many unsolved issues in managing the information flow in the pharmaceutical supply chain. In this study, we reviewed the benefits of using different levels of an integrated information system in the supply chain and the possible challenges ahead. PMID:26664401

  13. Postoperative ventilatory and circulatory effects of heating after aortocoronary bypass surgery. Extended rewarming during cardiopulmonary bypass and postoperative radiant heat supply.

    PubMed

    Joachimsson, P O; Nyström, S O; Tydén, H

    1987-08-01

    Twenty-four patients with stable angina pectoris were studied after aortocoronary bypass surgery with hypothermic cardiopulmonary bypass (CPB). Twelve patients (radiant heat supply group) were rewarmed during CPB to a nasopharyngeal temperature of at least 38 degrees C and a mean rectal temperature of 34.4 degrees C. Postoperatively they received radiant heat supply from a thermal ceiling. In addition, a heating water mattress was used during the end of the operation and heated, humidified inspired gases were administered intra- and postoperatively. The other 12 patients (combination heat supply group) had the rewarming during CPB extended until the rectal temperature exceeded 36 degrees C, but otherwise received the same treatment as the radiant heat supply group. The combination of extended rewarming during CPB and postoperative radiant heat supply significantly reduced oxygen uptake, carbon dioxide production and the required ventilation volumes during early recovery as compared with the values in the radiant heat supply group. The reduced metabolic demands were accompanied by lower cardiac index and oxygen delivery, which, however, were sufficient for adequate tissue perfusion as judged by the similarity in oxygen extraction and arterial base excess values in the two groups. The metabolic demands and ventilatory requirements were reduced to a level at which safe early extubation is possible.

  14. The Anaesthesia Gas Supply System

    PubMed Central

    Das, Sabyasachi; Chattopadhyay, Subhrajyoti; Bose, Payel

    2013-01-01

    The anaesthesia gas supply system is designed to provide a safe, cost-effective and convenient system for the delivery of medical gases at the point of-use. The doctrine of the anaesthesia gas supply system is based on four essential principles: Identity, continuity, adequacy and quality. Knowledge about gas supply system is an integral component of safe anaesthetic practice. Mishaps involving the malfunction or misuse of medical gas supply to operating theatres have cost many lives. The medical gases used in anaesthesia and intensive care are oxygen, nitrous oxide, medical air, entonox, carbon dioxide and heliox. Oxygen is one of the most widely used gases for life-support and respiratory therapy besides anaesthetic procedures. In this article, an effort is made to describe the production, storage and delivery of anaesthetic gases. The design of anaesthesia equipment must take into account the local conditions such as climate, demand and power supply. The operational policy of the gas supply system should have a backup plan to cater to the emergency need of the hospital, in the event of the loss of the primary source of supply. PMID:24249882

  15. Oxygen Therapy

    MedlinePlus

    Oxygen therapy is a treatment that provides you with extra oxygen. Oxygen is a gas that your body needs to function. Normally, your lungs absorb oxygen from the air you breathe. But some conditions ...

  16. Which Food Security Determinants Predict Adequate Vegetable Consumption among Rural Western Australian Children?

    PubMed

    Godrich, Stephanie L; Lo, Johnny; Davies, Christina R; Darby, Jill; Devine, Amanda

    2017-01-03

    Improving the suboptimal vegetable consumption among the majority of Australian children is imperative in reducing chronic disease risk. The objective of this research was to determine whether there was a relationship between food security determinants (FSD) (i.e., food availability, access, and utilisation dimensions) and adequate vegetable consumption among children living in regional and remote Western Australia (WA). Caregiver-child dyads (n = 256) living in non-metropolitan/rural WA completed cross-sectional surveys that included questions on FSD, demographics and usual vegetable intake. A total of 187 dyads were included in analyses, which included descriptive and logistic regression analyses via IBM SPSS (version 23). A total of 13.4% of children in this sample had adequate vegetable intake. FSD that met inclusion criteria (p ≤ 0.20) for multivariable regression analyses included price; promotion; quality; location of food outlets; variety of vegetable types; financial resources; and transport to outlets. After adjustment for potential demographic confounders, the FSD that predicted adequate vegetable consumption were, variety of vegetable types consumed (p = 0.007), promotion (p = 0.017), location of food outlets (p = 0.027), and price (p = 0.043). Food retail outlets should ensure that adequate varieties of vegetable types (i.e., fresh, frozen, tinned) are available, vegetable messages should be promoted through food retail outlets and in community settings, towns should include a range of vegetable purchasing options, increase their reliance on a local food supply and increase transport options to enable affordable vegetable purchasing.

  17. Power supply

    DOEpatents

    Yakymyshyn, Christopher Paul; Hamilton, Pamela Jane; Brubaker, Michael Allen

    2007-12-04

    A modular, low weight impedance dropping power supply with battery backup is disclosed that can be connected to a high voltage AC source and provide electrical power at a lower voltage. The design can be scaled over a wide range of input voltages and over a wide range of output voltages and delivered power.

  18. Region 9: Arizona Adequate Letter (10/14/2003)

    EPA Pesticide Factsheets

    This is a letter from Jack P. Broadben,. Director, to Nancy Wrona and Dennis Smith informing them that Maricopa County's motor vehicle emissions budgets in the 2003 MAGCO Maintenance Plan are adequate for transportation conformity purposes.

  19. Region 6: Texas Adequate Letter (4/16/2010)

    EPA Pesticide Factsheets

    This letter from EPA to Texas Commission on Environmental Quality determined 2021 motor vehicle emission budgets for nitrogen oxides (NOx) and volatile organic compounds (VOCs) for Beaumont/Port Arthur area adequate for transportation conformity purposes

  20. Region 2: New Jersey Adequate Letter (5/23/2002)

    EPA Pesticide Factsheets

    This April 22, 2002 letter from EPA to the New Jersey Department of Environmental Protection determined 2007 and 2014 Carbon Monoxide (CO) Mobile Source Emissions Budgets adequate for transportation conformity purposes and will be announced in the Federal

  1. Region 8: Colorado Adequate Letter (10/29/2001)

    EPA Pesticide Factsheets

    This letter from EPA to Colorado Department of Public Health and Environment determined Denvers' particulate matter (PM10) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes.

  2. Region 1: New Hampshire Adequate Letter (8/12/2008)

    EPA Pesticide Factsheets

    This July 9, 2008 letter from EPA to the New Hampshire Department of Environmental Services, determined the 2009 Motor Vehicle Emissions Budgets (MVEBs) are adequate for transportation conformity purposes and will be announced in the Federal Register (FR).

  3. Region 8: Colorado Adequate Letter (1/20/2004)

    EPA Pesticide Factsheets

    This letter from EPA to Colorado Department of Public Health and Environment determined Greeleys' Carbon Monoxide (CO) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes and will be announced in the FR.

  4. Region 8: Utah Adequate Letter (6/10/2005)

    EPA Pesticide Factsheets

    This letter from EPA to Utah Department of Environmental Quality determined Salt Lake Citys' and Ogdens' Carbon Monoxide (CO) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes.

  5. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  6. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  7. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  8. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  9. 15 CFR 970.404 - Adequate exploration plan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ENVIRONMENTAL DATA SERVICE DEEP SEABED MINING REGULATIONS FOR EXPLORATION LICENSES Certification of Applications § 970.404 Adequate exploration plan. Before he may certify an application, the Administrator must...

  10. Region 6: New Mexico Adequate Letter (8/21/2003)

    EPA Pesticide Factsheets

    This is a letter from Carl Edlund, Director, to Alfredo Santistevan regarding MVEB's contained in the latest revision to the Albuquerque Carbon Monoxide State Implementation Plan (SIP) are adequate for transportation conformity purposes.

  11. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  12. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  13. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  14. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  15. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  16. 10 CFR 1304.114 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... contained in a system of records are adequately trained to protect the security and privacy of such records..., by degaussing or by overwriting with the appropriate security software, in accordance...

  17. 4 CFR 200.14 - Responsibility for maintaining adequate safeguards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... require access to and use of records contained in a system of records are adequately trained to protect... with the appropriate security software, in accordance with regulations of the Archivist of the...

  18. Region 9: Nevada Adequate Letter (3/30/2006)

    EPA Pesticide Factsheets

    This is a letter from Deborah Jordan, Director, to Leo M. Drozdoff regarding Nevada's motor vehicle emissions budgets in the 2005 Truckee Meadows CO Redesignation Request and Maintenance Plan are adequate for transportation conformity decisions.

  19. Power supply

    DOEpatents

    Hart, Edward J.; Leeman, James E.; MacDougall, Hugh R.; Marron, John J.; Smith, Calvin C.

    1976-01-01

    An electric power supply employs a striking means to initiate ferroelectric elements which provide electrical energy output which subsequently initiates an explosive charge which initiates a second ferroelectric current generator to deliver current to the coil of a magnetic field current generator, creating a magnetic field around the coil. Continued detonation effects compression of the magnetic field and subsequent generation and delivery of a large output current to appropriate output loads.

  20. Cyanobacterial Diazotrophy and Earth’s Delayed Oxygenation

    PubMed Central

    Olson, Stephanie L.; Reinhard, Christopher T.; Lyons, Timothy W.

    2016-01-01

    The redox landscape of Earth’s ocean-atmosphere system has changed dramatically throughout Earth history. Although Earth’s protracted oxygenation is undoubtedly the consequence of cyanobacterial oxygenic photosynthesis, the relationship between biological O2 production and Earth’s redox evolution remains poorly understood. Existing models for Earth’s oxygenation cannot adequately explain the nearly 2.5 billion years delay between the origin of oxygenic photosynthesis and the oxygenation of the deep ocean, in large part owing to major deficiencies in our understanding of the coevolution of O2 and Earth’s key biogeochemical cycles (e.g., the N cycle). For example, although possible links between O2 and N scarcity have been previously explored, the consequences of N2 limitation for net biological O2 production have not been examined thoroughly. Here, we revisit the prevailing view that N2 fixation has always been able to keep pace with P supply and discuss the possibility that bioavailable N, rather than P, limited export production for extended periods of Earth’s history. Based on the observation that diazotrophy occurs at the expense of oxygenesis in the modern ocean, we suggest that an N-limited biosphere may be inherently less oxygenic than a P-limited biosphere—and that cyanobacterial diazotrophy was a primary control on the timing and tempo of Earth’s oxygenation by modulating net biogenic O2 fluxes. We further hypothesize that negative feedbacks inhibit the transition between N and P limitation, with the implication that the pervasive accumulation of O2 in Earth’s ocean-atmosphere system may not have been an inevitable consequence of oxygenic photosynthesis by marine cyanobacteria. PMID:27721813

  1. High pressure autothermal reforming in low oxygen environments

    NASA Astrophysics Data System (ADS)

    Reese, Mark A.; Turn, Scott Q.; Cui, Hong

    Recent interest in fuel cells has led to the conceptual design of an ocean floor, fuel cell-based, power generating station fueled by methane from natural gas seeps or from the controlled decomposition of methane hydrates. Because the dissolved oxygen concentration in deep ocean water is too low to provide adequate supplies to a fuel processor and fuel cell, oxygen must be stored onboard the generating station. A lab scale catalytic autothermal reformer capable of operating at pressures of 6-50 bar was constructed and tested. The objective of the experimental program was to maximize H 2 production per mole of O 2 supplied (H 2(out)/O 2(in)). Optimization, using oxygen-to-carbon (O 2/C) and water-to-carbon (S/C) ratios as independent variables, was conducted at three pressures using bottled O 2. Surface response methodology was employed using a 2 2 factorial design. Optimal points were validated using H 2O 2 as both a stored oxidizer and steam source. The optimal experimental conditions for maximizing the moles of H 2(out)/O 2(in) occurred at a S/C ratio of 3.00-3.35 and an O 2/C ratio of 0.44-0.48. When using H 2O 2 as the oxidizer, the moles of H 2(out)/O 2(in) increased ≤14%. An equilibrium model was also used to compare experimental and theoretical results.

  2. Switching power supply

    DOEpatents

    Mihalka, A.M.

    1984-06-05

    The invention is a repratable capacitor charging, switching power supply. A ferrite transformer steps up a dc input. The transformer primary is in a full bridge configuration utilizing power MOSFETs as the bridge switches. The transformer secondary is fed into a high voltage, full wave rectifier whose output is connected directly to the energy storage capacitor. The transformer is designed to provide adequate leakage inductance to limit capacitor current. The MOSFETs are switched to the variable frequency from 20 to 50 kHz to charge a capacitor from 0.6 kV. The peak current in a transformer primary and secondary is controlled by increasing the pulse width as the capacitor charges. A digital ripple counter counts pulses and after a preselected desired number is reached an up-counter is clocked.

  3. Regulatory requirements for providing adequate veterinary care to research animals.

    PubMed

    Pinson, David M

    2013-09-01

    Provision of adequate veterinary care is a required component of animal care and use programs in the United States. Program participants other than veterinarians, including non-medically trained research personnel and technicians, also provide veterinary care to animals, and administrators are responsible for assuring compliance with federal mandates regarding adequate veterinary care. All program participants therefore should understand the regulatory requirements for providing such care. The author provides a training primer on the US regulatory requirements for the provision of veterinary care to research animals. Understanding the legal basis and conditions of a program of veterinary care will help program participants to meet the requirements advanced in the laws and policies.

  4. Improved ASTM G72 Test Method for Ensuring Adequate Fuel-to-Oxidizer Ratios

    NASA Technical Reports Server (NTRS)

    Juarez, Alfredo; Harper, Susana Tapia

    2016-01-01

    The ASTM G72/G72M-15 Standard Test Method for Autogenous Ignition Temperature of Liquids and Solids in a High-Pressure Oxygen-Enriched Environment is currently used to evaluate materials for the ignition susceptibility driven by exposure to external heat in an enriched oxygen environment. Testing performed on highly volatile liquids such as cleaning solvents has proven problematic due to inconsistent test results (non-ignitions). Non-ignition results can be misinterpreted as favorable oxygen compatibility, although they are more likely associated with inadequate fuel-to-oxidizer ratios. Forced evaporation during purging and inadequate sample size were identified as two potential causes for inadequate available sample material during testing. In an effort to maintain adequate fuel-to-oxidizer ratios within the reaction vessel during test, several parameters were considered, including sample size, pretest sample chilling, pretest purging, and test pressure. Tests on a variety of solvents exhibiting a range of volatilities are presented in this paper. A proposed improvement to the standard test protocol as a result of this evaluation is also presented. Execution of the final proposed improved test protocol outlines an incremental step method of determining optimal conditions using increased sample sizes while considering test system safety limits. The proposed improved test method increases confidence in results obtained by utilizing the ASTM G72 autogenous ignition temperature test method and can aid in the oxygen compatibility assessment of highly volatile liquids and other conditions that may lead to false non-ignition results.

  5. Comparability and Reliability Considerations of Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Maier, Kimberly S.; Maiti, Tapabrata; Dass, Sarat C.; Lim, Chae Young

    2012-01-01

    The purpose of this study is to develop an estimate of Adequate Yearly Progress (AYP) that will allow for reliable and valid comparisons among student subgroups, schools, and districts. A shrinkage-type estimator of AYP using the Bayesian framework is described. Using simulated data, the performance of the Bayes estimator will be compared to…

  6. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operate actively in accordance with your Articles and within the context of your business plan, as... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Adequate capital for Licensees. 107.200 Section 107.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL...

  7. 13 CFR 107.200 - Adequate capital for Licensees.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... operate actively in accordance with your Articles and within the context of your business plan, as... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Adequate capital for Licensees. 107.200 Section 107.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL...

  8. Is the Stock of VET Skills Adequate? Assessment Methodologies.

    ERIC Educational Resources Information Center

    Blandy, Richard; Freeland, Brett

    In Australia and elsewhere, four approaches have been used to determine whether stocks of vocational education and training (VET) skills are adequate to meet industry needs. The four methods are as follows: (1) the manpower requirements approach; (2) the international, national, and industry comparisons approach; (3) the labor market analysis…

  9. Do Beginning Teachers Receive Adequate Support from Their Headteachers?

    ERIC Educational Resources Information Center

    Menon, Maria Eliophotou

    2012-01-01

    The article examines the problems faced by beginning teachers in Cyprus and the extent to which headteachers are considered to provide adequate guidance and support to them. Data were collected through interviews with 25 school teachers in Cyprus, who had recently entered teaching (within 1-5 years) in public primary schools. According to the…

  10. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  11. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  12. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  13. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  14. 13 CFR 108.200 - Adequate capital for NMVC Companies.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Companies. 108.200 Section 108.200 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM Qualifications for the NMVC Program Capitalizing A Nmvc Company § 108.200 Adequate capital for NMVC Companies. You must meet the requirements of §§ 108.200-108.230 in order...

  15. Understanding Your Adequate Yearly Progress (AYP), 2011-2012

    ERIC Educational Resources Information Center

    Missouri Department of Elementary and Secondary Education, 2011

    2011-01-01

    The "No Child Left Behind Act (NCLB) of 2001" requires all schools, districts/local education agencies (LEAs) and states to show that students are making Adequate Yearly Progress (AYP). NCLB requires states to establish targets in the following ways: (1) Annual Proficiency Target; (2) Attendance/Graduation Rates; and (3) Participation…

  16. 34 CFR 200.13 - Adequate yearly progress in general.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Adequate yearly progress in general. 200.13 Section 200.13 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE...

  17. 34 CFR 200.13 - Adequate yearly progress in general.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Adequate yearly progress in general. 200.13 Section 200.13 Education Regulations of the Offices of the Department of Education OFFICE OF ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION TITLE I-IMPROVING THE ACADEMIC ACHIEVEMENT OF THE...

  18. Region 9: Arizona Adequate Letter (11/1/2001)

    EPA Pesticide Factsheets

    This is a letter from Jack P. Broadbent, Director, Air Division to Nancy Wrona and James Bourney informing them of the adequacy of Revised MAG 1999 Serious Area Carbon Monoxide Plan and that the MAG CO Plan is adequate for Maricopa County.

  19. Effects of oxygen deprivation on incubated rat soleus muscle

    NASA Technical Reports Server (NTRS)

    Fagan, Julie M.; Tischler, Marc E.

    1989-01-01

    Isolated soleus muscle deprived of oxygen produces more lactate and alanine than oxygen-supplied muscle. Oxygenated muscle synthesized glutamine, while anoxic muscle used this amino acid. Oxygen deprivation decreased adenine nucleotides leading to the efflux of nucleosides. Protein synthesis and degradation responded differently to anoxia. Synthesis almost completely ceased, while proteolysis increased. Therefore, protein degradation in soleus muscle is enhanced when energy supplies and oxygen tension are low.

  20. Which Food Security Determinants Predict Adequate Vegetable Consumption among Rural Western Australian Children?

    PubMed Central

    Godrich, Stephanie L.; Lo, Johnny; Davies, Christina R.; Darby, Jill; Devine, Amanda

    2017-01-01

    Improving the suboptimal vegetable consumption among the majority of Australian children is imperative in reducing chronic disease risk. The objective of this research was to determine whether there was a relationship between food security determinants (FSD) (i.e., food availability, access, and utilisation dimensions) and adequate vegetable consumption among children living in regional and remote Western Australia (WA). Caregiver-child dyads (n = 256) living in non-metropolitan/rural WA completed cross-sectional surveys that included questions on FSD, demographics and usual vegetable intake. A total of 187 dyads were included in analyses, which included descriptive and logistic regression analyses via IBM SPSS (version 23). A total of 13.4% of children in this sample had adequate vegetable intake. FSD that met inclusion criteria (p ≤ 0.20) for multivariable regression analyses included price; promotion; quality; location of food outlets; variety of vegetable types; financial resources; and transport to outlets. After adjustment for potential demographic confounders, the FSD that predicted adequate vegetable consumption were, variety of vegetable types consumed (p = 0.007), promotion (p = 0.017), location of food outlets (p = 0.027), and price (p = 0.043). Food retail outlets should ensure that adequate varieties of vegetable types (i.e., fresh, frozen, tinned) are available, vegetable messages should be promoted through food retail outlets and in community settings, towns should include a range of vegetable purchasing options, increase their reliance on a local food supply and increase transport options to enable affordable vegetable purchasing. PMID:28054955

  1. Army General Fund Adjustments Not Adequately Documented or Supported

    DTIC Science & Technology

    2016-07-26

    statements were unreliable and lacked an adequate audit trail. Furthermore, DoD and Army managers could not rely on the data in their accounting...risk that AGF financial statements will be materially misstated and the Army will not achieve audit readiness by the congressionally mandated...and $6.5 trillion in yearend adjustments made to Army General Fund data during FY 2015 financial statement compilation. We conducted this audit in

  2. Using oxygen at home

    MedlinePlus

    Oxygen - home use; COPD - home oxygen; Chronic obstructive airways disease - home oxygen; Chronic obstructive lung disease - home oxygen; Chronic bronchitis - home oxygen; Emphysema - home oxygen; Chronic respiratory ...

  3. The Goal of Adequate Nutrition: Can It Be Made Affordable, Sustainable, and Universal?

    PubMed

    McFarlane, Ian

    2016-11-30

    Until about 1900, large proportions of the world population endured hunger and poverty. The 20th century saw world population increase from 1.6 to 6.1 billion, accompanied and to some extent made possible by rapid improvements in health standards and food supply, with associated advances in agricultural and nutrition sciences. In this paper, I use the application of linear programming (LP) in preparation of rations for farm animals to illustrate a method of calculating the lowest cost of a human diet selected from locally available food items, constrained to provide recommended levels of food energy and nutrients; then, to find a realistic minimum cost, I apply the further constraint that the main sources of food energy in the costed diet are weighted in proportion to the actual reported consumption of food items in that area. Worldwide variations in dietary preferences raise the issue as to the sustainability of popular dietary regimes, and the paper reviews the factors associated with satisfying requirements for adequate nutrition within those regimes. The ultimate physical constraints on food supply are described, together with the ways in which climate change may affect those constraints. During the 20th century, food supply increased sufficiently in most areas to keep pace with the rapid increase in world population. Many challenges will need to be overcome if food supply is to continue to meet demand, and those challenges are made more severe by rising expectations of quality of life in the developing world, as well as by the impacts of climate change on agriculture and aquaculture.

  4. The Goal of Adequate Nutrition: Can It Be Made Affordable, Sustainable, and Universal?

    PubMed Central

    McFarlane, Ian

    2016-01-01

    Until about 1900, large proportions of the world population endured hunger and poverty. The 20th century saw world population increase from 1.6 to 6.1 billion, accompanied and to some extent made possible by rapid improvements in health standards and food supply, with associated advances in agricultural and nutrition sciences. In this paper, I use the application of linear programming (LP) in preparation of rations for farm animals to illustrate a method of calculating the lowest cost of a human diet selected from locally available food items, constrained to provide recommended levels of food energy and nutrients; then, to find a realistic minimum cost, I apply the further constraint that the main sources of food energy in the costed diet are weighted in proportion to the actual reported consumption of food items in that area. Worldwide variations in dietary preferences raise the issue as to the sustainability of popular dietary regimes, and the paper reviews the factors associated with satisfying requirements for adequate nutrition within those regimes. The ultimate physical constraints on food supply are described, together with the ways in which climate change may affect those constraints. During the 20th century, food supply increased sufficiently in most areas to keep pace with the rapid increase in world population. Many challenges will need to be overcome if food supply is to continue to meet demand, and those challenges are made more severe by rising expectations of quality of life in the developing world, as well as by the impacts of climate change on agriculture and aquaculture. PMID:28231177

  5. Genetic modification of preimplantation embryos: toward adequate human research policies.

    PubMed

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo modification proposals might not receive adequate scientific and ethical scrutiny. This article describes current policy shortcomings and recommends policy actions designed to ensure that the investigational genetic modification of embryos meets accepted standards for research on human subjects.

  6. Elements for adequate informed consent in the surgical context.

    PubMed

    Abaunza, Hernando; Romero, Klaus

    2014-07-01

    Given a history of atrocities and violations of ethical principles, several documents and regulations have been issued by a wide variety of organizations. They aim at ensuring that health care and clinical research adhere to defined ethical principles. A fundamental component was devised to ensure that the individual has been provided the necessary information to make an informed decision regarding health care or participation in clinical research. This article summarizes the history and regulations for informed consent and discusses suggested components for adequate consent forms for daily clinical practice in surgery as well as clinical research.

  7. Oxygen analyzer

    DOEpatents

    Benner, William H.

    1986-01-01

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N.sub.2), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable oxygen obtained by decomposing the sample at 1135.degree. C., or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135.degree. C. as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N.sub.2, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  8. Oxygen Therapy

    MedlinePlus

    ... stored as a gas or liquid in special tanks. These tanks can be delivered to your home and contain ... they won’t run out of oxygen. Portable tanks and oxygen concentrators may make it easier for ...

  9. Quantifying dose to the reconstructed breast: Can we adequately treat?

    SciTech Connect

    Chung, Eugene; Marsh, Robin B.; Griffith, Kent A.; Moran, Jean M.; Pierce, Lori J.

    2013-04-01

    To evaluate how immediate reconstruction (IR) impacts postmastectomy radiotherapy (PMRT) dose distributions to the reconstructed breast (RB), internal mammary nodes (IMN), heart, and lungs using quantifiable dosimetric end points. 3D conformal plans were developed for 20 IR patients, 10 autologous reconstruction (AR), and 10 expander-implant (EI) reconstruction. For each reconstruction type, 5 right- and 5 left-sided reconstructions were selected. Two plans were created for each patient, 1 with RB coverage alone and 1 with RB + IMN coverage. Left-sided EI plans without IMN coverage had higher heart Dmean than left-sided AR plans (2.97 and 0.84 Gy, p = 0.03). Otherwise, results did not vary by reconstruction type and all remaining metrics were evaluated using a combined AR and EI dataset. RB coverage was adequate regardless of laterality or IMN coverage (Dmean 50.61 Gy, D95 45.76 Gy). When included, IMN Dmean and D95 were 49.57 and 40.96 Gy, respectively. Mean heart doses increased with left-sided treatment plans and IMN inclusion. Right-sided treatment plans and IMN inclusion increased mean lung V{sub 20}. Using standard field arrangements and 3D planning, we observed excellent coverage of the RB and IMN, regardless of laterality or reconstruction type. Our results demonstrate that adequate doses can be delivered to the RB with or without IMN coverage.

  10. Beyond oxygen: complex regulation and activity of hypoxia inducible factors in pregnancy

    PubMed Central

    Pringle, K.G.; Kind, K.L.; Sferruzzi-Perri, A.N.; Thompson, J.G.; Roberts, C.T.

    2010-01-01

    In the first trimester the extravillous cytotrophoblast cells occlude the uterine spiral arterioles creating a low oxygen environment early in pregnancy, which is essential for pregnancy success. Paradoxically, shallow trophoblast invasion and defective vascular remodelling of the uterine spiral arteries in the first trimester may result in impaired placental perfusion and chronic placental ischemia and hypoxia later in gestation leading to adverse pregnancy outcomes. The hypoxia inducible factors (HIFs) are key mediators of the response to low oxygen. We aimed to elucidate mechanisms of regulation of HIFs and the role these may play in the control of placental differentiation, growth and function in both normal and pathological pregnancies. The Pubmed database was consulted for identification of the most relevant published articles. Search terms used were oxygen, placenta, trophoblast, pregnancy, HIF and hypoxia. The HIFs are able to function throughout all aspects of normal and abnormal placental differentiation, growth and function; during the first trimester (physiologically low oxygen), during mid-late gestation (where there is adequate supply of blood and oxygen to the placenta) and in pathological pregnancies complicated by placental hypoxia/ischemia. During normal pregnancy HIFs may respond to complex alterations in oxygen, hormones, cytokines and growth factors to regulate placental invasion, differentiation, transport and vascularization. In the ever-changing environment created during pregnancy, the HIFs appear to act as key mediators of placental development and function and thereby are likely to be important contributors to both normal and adverse pregnancy outcomes. PMID:19926662

  11. [Apneic oxygenation].

    PubMed

    Alekseev, A V; Vyzhigina, M A; Parshin, V D; Fedorov, D S

    2013-01-01

    Recent technological advances in thoracic and tracheal surgery make the anaesthesiologist use different respiratory techniques during the operation. Apneic oxygenation is a one of alternative techniques. This method is relatively easy in use, does not require special expensive equipment and is the only possible technique in several clinical situations when other respiratory methods are undesirable or cannot be used. However there is no enough information about apneic oxygenation in Russian. This article reviews publications about apneic oxygenation. The review deals with experiments on diffusion respiration in animals, physiological changes during apneic oxygenation in man and defines clinical cases when apneic oxygenation can be used.

  12. Oxygen analyzer

    DOEpatents

    Benner, W.H.

    1984-05-08

    An oxygen analyzer which identifies and classifies microgram quantities of oxygen in ambient particulate matter and for quantitating organic oxygen in solvent extracts of ambient particulate matter. A sample is pyrolyzed in oxygen-free nitrogen gas (N/sub 2/), and the resulting oxygen quantitatively converted to carbon monoxide (CO) by contact with hot granular carbon (C). Two analysis modes are made possible: (1) rapid determination of total pyrolyzable obtained by decomposing the sample at 1135/sup 0/C, or (2) temperature-programmed oxygen thermal analysis obtained by heating the sample from room temperature to 1135/sup 0/C as a function of time. The analyzer basically comprises a pyrolysis tube containing a bed of granular carbon under N/sub 2/, ovens used to heat the carbon and/or decompose the sample, and a non-dispersive infrared CO detector coupled to a mini-computer to quantitate oxygen in the decomposition products and control oven heating.

  13. Prostate cancer between prognosis and adequate/proper therapy

    PubMed Central

    Grozescu, T; Popa, F

    2017-01-01

    Knowing the indolent, non-invasive nature of most types of prostate cancer, as well as the simple fact that the disease seems more likely to be associated with age rather than with other factors (50% of men at the age of 50 and 80% at the age of 80 have it [1], with or without presenting any symptom), the big challenge of this clinical entity was to determine severity indicators (so far insufficient) to guide the physician towards an adequate attitude in the clinical setting. The risk of over-diagnosing and over-treating many prostate cancer cases (indicated by all the major European and American studies) is real and poses many question marks. The present paper was meant to deliver new research data and to reset the clinical approach in prostate cancer cases. PMID:28255369

  14. The cerebellopontine angle: does the translabyrinthine approach give adequate access?

    PubMed

    Fagan, P A; Sheehy, J P; Chang, P; Doust, B D; Coakley, D; Atlas, M D

    1998-05-01

    A long-standing but unfounded criticism of the translabyrinthine approach is the misperception that this approach does not give adequate access to the cerebellopontine angle. Because of what is perceived as limited visualization and operating space within the cerebellopontine angle, some surgeons still believe that the translabyrinthine approach is inappropriate for large acoustic tumors. In this study, the surgical access to the cerebellopontine angle by virtue of the translabyrinthine approach is measured and analyzed. The parameters are compared with those measured for the retrosigmoid approach. This series objectively confirms that the translabyrinthine approach offers the neurotologic surgeon a shorter operative depth to the tumor, via a similar-sized craniotomy. This permits superior visualization by virtue of a wider angle of surgical access. Such access is achieved with the merit of minimal cerebellar retraction.

  15. Barriers to adequate prenatal care utilization in American Samoa

    PubMed Central

    Hawley, Nicola L; Brown, Carolyn; Nu’usolia, Ofeira; Ah-Ching, John; Muasau-Howard, Bethel; McGarvey, Stephen T

    2013-01-01

    Objective To describe the utilization of prenatal care in American Samoan women and to identify socio-demographic predictors of inadequate prenatal care utilization. Methods Using data from prenatal clinic records, women (n=692) were categorized according to the Adequacy of Prenatal Care Utilization Index as having received adequate plus, adequate, intermediate or inadequate prenatal care during their pregnancy. Categorical socio-demographic predictors of the timing of initiation of prenatal care (week of gestation) and the adequacy of received services were identified using one way Analysis of Variance (ANOVA) and independent samples t-tests. Results Between 2001 and 2008 85.4% of women received inadequate prenatal care. Parity (P=0.02), maternal unemployment (P=0.03), and both parents being unemployed (P=0.03) were negatively associated with the timing of prenatal care initation. Giving birth in 2007–2008, after a prenatal care incentive scheme had been introduced in the major hospital, was associated with earlier initiation of prenatal care (20.75 versus 25.12 weeks; P<0.01) and improved adequacy of received services (95.04% versus 83.8%; P=0.02). Conclusion The poor prenatal care utilization in American Samoa is a major concern. Improving healthcare accessibility will be key in encouraging women to attend prenatal care. The significant improvements in the adequacy of prenatal care seen in 2007–2008 suggest that the prenatal care incentive program implemented in 2006 may be a very positive step toward addressing issues of prenatal care utilization in this population. PMID:24045912

  16. Cleaning supplies and equipment

    MedlinePlus

    ... gov/ency/patientinstructions/000443.htm Cleaning supplies and equipment To use the sharing features on this page, ... to clean supplies and equipment. Disinfecting Supplies and Equipment Start by wearing the right personal protective equipment ( ...

  17. Paraffin as oxygen vector modulates tyrosine phenol lyase production by Citrobacter freundii MTCC 2424.

    PubMed

    Azmi, Wamik; Kumar, Ajay; Dev, Varun

    2013-06-01

    The efficiency of three oxygen-vectors liquid paraffin, silicone oil and n-dodecane in the production of tyrosine phenol lyase (TPL) by Citrobacter freundii MTCC 2424 was evaluated at 4% (v/v) concentration. The liquid paraffin as oxygenvectors was found to exhibit a stimulatory effect on TPL synthesis. The liquid paraffin at 6% (v/v) resulted in 34% increase in the TPL synthesis accompanied by a 13% increase in the production of cell mass at a 10 L scale. This improvement in TPL and cell mass production in the presence of liquid paraffin can be related to the fact that liquid paraffin was capable of maintaining dissolved O2 concentration above 28% throughout the course of the fermentation. Maintenance of the dissolved O2 concentration above 28% could be viewed in terms of an adequate oxygen supply to the rapidly dividing cells of the bacterium, which in turn resulted in enhanced synthesis of TPL and cell mass.

  18. Energy management study for lunar oxygen production

    NASA Technical Reports Server (NTRS)

    Fazzolare, R. A.; Wong-Swanson, B. G.

    1989-01-01

    Energy management opportunities in the process of hydrogen reduction of ilmenite for lunar oxygen production are being investigated. An optimal energy system to supply the power requirements for the process will be determined.

  19. Life Support with Failures and Variable Supply

    NASA Technical Reports Server (NTRS)

    Jones, Harry

    2010-01-01

    The life support system for long duration missions will recycle oxygen and water to reduce the material resupply mass from Earth. The impact of life support failures was investigated by dynamic simulation of a lunar outpost habitat life support model. The model was modified to simulate resupply delays, power failures, recycling system failures, and storage failures. Many failures impact the lunar outpost water supply directly or indirectly, depending on the water balance and water storage. Failure effects on the water supply are reduced if Extra Vehicular Activity (EVA) water use is low and the water supply is ample. Additional oxygen can be supplied by scavenging unused propellant or by production from regolith, but the amounts obtained can vary significantly. The requirements for oxygen and water can also vary significantly, especially for EVA. Providing storage buffers can improve efficiency and reliability, and minimize the chance of supply failing to meet demand. Life support failures and supply variations can be survivable if effective solutions are provided by the system design

  20. The oxygen paradox of neurovascular coupling

    PubMed Central

    Leithner, Christoph; Royl, Georg

    2014-01-01

    The coupling of cerebral blood flow (CBF) to neuronal activity is well preserved during evolution. Upon changes in the neuronal activity, an incompletely understood coupling mechanism regulates diameter changes of supplying blood vessels, which adjust CBF within seconds. The physiologic brain tissue oxygen content would sustain unimpeded brain function for only 1 second if continuous oxygen supply would suddenly stop. This suggests that the CBF response has evolved to balance oxygen supply and demand. Surprisingly, CBF increases surpass the accompanying increases of cerebral metabolic rate of oxygen (CMRO2). However, a disproportionate CBF increase may be required to increase the concentration gradient from capillary to tissue that drives oxygen delivery. However, the brain tissue oxygen content is not zero, and tissue pO2 decreases could serve to increase oxygen delivery without a CBF increase. Experimental evidence suggests that CMRO2 can increase with constant CBF within limits and decreases of baseline CBF were observed with constant CMRO2. This conflicting evidence may be viewed as an oxygen paradox of neurovascular coupling. As a possible solution for this paradox, we hypothesize that the CBF response has evolved to safeguard brain function in situations of moderate pathophysiological interference with oxygen supply. PMID:24149931

  1. Optical oxygen concentration monitor

    DOEpatents

    Kebabian, P.

    1997-07-22

    A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest. 4 figs.

  2. Petroleum supply annual 1994. Volume 1

    SciTech Connect

    1995-05-22

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1994 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1994, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Below is a description of each section in Volume 1 of the PSA.

  3. Petroleum supply annual 1993. Volume 1

    SciTech Connect

    Not Available

    1994-06-01

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1993 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1993, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Below is a description of each section in Volume 1 of the PSA.

  4. Systemic Crisis of Civilization: In Search for Adequate Solution

    NASA Astrophysics Data System (ADS)

    Khozin, Grigori

    In December 1972 a jumbo jet crashed in the Florida Everglades with the loss of 101 lives. The pilot, distracted by a minor malfunction, failed to note until too late the warning signal that - correctly - indicated an impending disaster. His sudden, astonished cry of Hey, what happening here? were his last words 1. Three decades after this tragic episode, as the Humankind approaches the threshold of the third Millennium, the problem of adequate reaction to warning signals of different nature and of distinguishing minor malfunctions in everyday life of society, in economy and technology as well as in evolution of biosphere from grave threats to the world community and the phenomenon of life on our planet remains crucial to human survival and the future of Civilization. Rational use of knowledge and technology available to the world community remains in this context the corner stone of discussions on the destiny of the intelligent life both on the planet Earth and in the Universe (the fact of intelligent life in the Universe is to be detected by the Humankind)…

  5. ENSURING ADEQUATE SAFETY WHEN USING HYDROGEN AS A FUEL

    SciTech Connect

    Coutts, D

    2007-01-22

    Demonstration projects using hydrogen as a fuel are becoming very common. Often these projects rely on project-specific risk evaluations to support project safety decisions. This is necessary because regulations, codes, and standards (hereafter referred to as standards) are just being developed. This paper will review some of the approaches being used in these evolving standards, and techniques which demonstration projects can implement to bridge the gap between current requirements and stakeholder desires. Many of the evolving standards for hydrogen-fuel use performance-based language, which establishes minimum performance and safety objectives, as compared with prescriptive-based language that prescribes specific design solutions. This is being done for several reasons including: (1) concern that establishing specific design solutions too early will stifle invention, (2) sparse performance data necessary to support selection of design approaches, and (3) a risk-adverse public which is unwilling to accept losses that were incurred in developing previous prescriptive design standards. The evolving standards often contain words such as: ''The manufacturer shall implement the measures and provide the information necessary to minimize the risk of endangering a person's safety or health''. This typically implies that the manufacturer or project manager must produce and document an acceptable level of risk. If accomplished using comprehensive and systematic process the demonstration project risk assessment can ease the transition to widespread commercialization. An approach to adequately evaluate and document the safety risk will be presented.

  6. DARHT -- an adequate EIS: A NEPA case study

    SciTech Connect

    Webb, M.D.

    1997-08-01

    In April 1996 the US District Court in Albuquerque ruled that the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility Environmental Impact Statement (EIS), prepared by the Los Alamos Area Office, US Department of Energy (DOE), was adequate. The DARHT EIS had been prepared in the face of a lawsuit in only 10 months, a third of the time usually allotted for a DOE EIS, and for only a small fraction of the cost of a typical DOE EIS, and for only a small fraction of the cost of a typical DOE EIS. It subject was the first major facility to be built in decades for the DOE nuclear weapons stockpile stewardship program. It was the first EIS to be prepared for a proposal at DOE`s Los Alamos National Laboratory since 1979, and the first ever prepared by the Los Alamos Area Office. Much of the subject matter was classified. The facility had been specially designed to minimize impacts to a nearby prehistoric Native American ruin, and extensive consultation with American Indian Pueblos was required. The week that the draft EIS was published Laboratory biologists identified a previously unknown pair of Mexican spotted owls in the immediate vicinity of the project, bringing into play the consultation requirements of the Endangered Species Act. In spite of these obstacles, the resultant DARHT EIS was reviewed by the court and found to meet all statutory and regulatory requirements; the court praised the treatment of the classified material which served as a basis for the environmental analysis.

  7. Dose Limits for Man do not Adequately Protect the Ecosystem

    SciTech Connect

    Higley, Kathryn A.; Alexakhin, Rudolf M.; McDonald, Joseph C.

    2004-08-01

    It has been known for quite some time that different organisms display differing degrees of sensitivity to the effects of ionizing radiations. Some microorganisms such as the bacterium Micrococcus radiodurans, along with many species of invertebrates, are extremely radio-resistant. Humans might be categorized as being relatively sensitive to radiation, and are a bit more resistant than some pine trees. Therefore, it could be argued that maintaining the dose limits necessary to protect humans will also result in the protection of most other species of flora and fauna. This concept is usually referred to as the anthropocentric approach. In other words, if man is protected then the environment is also adequately protected. The ecocentric approach might be stated as; the health of humans is effectively protected only when the environment is not unduly exposed to radiation. The ICRP is working on new recommendations dealing with the protection of the environment, and this debate should help to highlight a number of relevant issues concerning that topic.

  8. Supply Security in Future Nuclear Fuel Markets

    SciTech Connect

    Seward, Amy M.; Wood, Thomas W.; Gitau, Ernest T.; Ford, Benjamin E.

    2013-11-18

    Previous PNNL work has shown the existing nuclear fuel markets to provide a high degree of supply security, including the ability to respond to supply disruptions that occur for technical and non-technical reasons. It is in the context of new reactor designs – that is, reactors likely to be licensed and market ready over the next several decades – that fuel supply security is most relevant. Whereas the fuel design and fabrication technology for existing reactors are well known, the construction of a new set of reactors could stress the ability of the existing market to provide adequate supply redundancy. This study shows this is unlikely to occur for at least thirty years, as most reactors likely to be built in the next three decades will be evolutions of current designs, with similar fuel designs to existing reactors.

  9. Health supply chain management.

    PubMed

    Zimmerman, Rolf; Gallagher, Pat

    2010-01-01

    This chapter gives an educational overview of: * The actual application of supply chain practice and disciplines required for service delivery improvement within the current health environment. * A rationale for the application of Supply Chain Management (SCM) approaches to the Health sector. * The tools and methods available for supply chain analysis and benchmarking. * Key supply chain success factors.

  10. Oxygen Generation Assembly Technology Development

    NASA Technical Reports Server (NTRS)

    Bagdigian, Robert; Cloud, Dale

    1999-01-01

    Hamilton Standard Space Systems International (HSSI) is under contract to NASA Marshall Space Flight Center (MSFC) to develop an Oxygen Generation Assembly (OGA) for the International Space Station (ISS). The International Space Station Oxygen Generation Assembly (OGA) electrolyzes potable water from the Water Recovery System (WRS) to provide gaseous oxygen to the Space Station module atmosphere. The OGA produces oxygen for metabolic consumption by crew and biological specimens. The OGA also replenishes oxygen lost by experiment ingestion, airlock depressurization, CO2 venting, and leakage. As a byproduct, gaseous hydrogen is generated. The hydrogen will be supplied at a specified pressure range above ambient to support future utilization. Initially, the hydrogen will be vented overboard to space vacuum. This paper describes the OGA integration into the ISS Node 3. It details the development history supporting the design and describes the OGA System characteristics and its physical layout.

  11. Appreciating Oxygen

    ERIC Educational Resources Information Center

    Weiss, Hilton M.

    2008-01-01

    Photosynthetic flora and microfauna utilize light from the sun to convert carbon dioxide and water into carbohydrates and oxygen. While these carbohydrates and their derivative hydrocarbons are generally considered to be fuels, it is the thermodynamically energetic oxygen molecule that traps, stores, and provides almost all of the energy that…

  12. On Adequate Comparisons of Antenna Phase Center Variations

    NASA Astrophysics Data System (ADS)

    Schoen, S.; Kersten, T.

    2013-12-01

    One important part for ensuring the high quality of the International GNSS Service's (IGS) products is the collection and publication of receiver - and satellite antenna phase center variations (PCV). The PCV are crucial for global and regional networks, since they introduce a global scale factor of up to 16ppb or changes in the height component with an amount of up to 10cm, respectively. Furthermore, antenna phase center variations are also important for precise orbit determination, navigation and positioning of mobile platforms, like e.g. the GOCE and GRACE gravity missions, or for the accurate Precise Point Positioning (PPP) processing. Using the EUREF Permanent Network (EPN), Baire et al. (2012) showed that individual PCV values have a significant impact on the geodetic positioning. The statements are further supported by studies of Steigenberger et al. (2013) where the impact of PCV for local-ties are analysed. Currently, there are five calibration institutions including the Institut für Erdmessung (IfE) contributing to the IGS PCV file. Different approaches like field calibrations and anechoic chamber measurements are in use. Additionally, the computation and parameterization of the PCV are completely different within the methods. Therefore, every new approach has to pass a benchmark test in order to ensure that variations of PCV values of an identical antenna obtained from different methods are as consistent as possible. Since the number of approaches to obtain these PCV values rises with the number of calibration institutions, there is the necessity for an adequate comparison concept, taking into account not only the numerical values but also stochastic information and computational issues of the determined PCVs. This is of special importance, since the majority of calibrated receiver antennas published by the IGS origin from absolute field calibrations based on the Hannover Concept, Wübbena et al. (2000). In this contribution, a concept for the adequate

  13. Are Vancomycin Trough Concentrations Adequate for Optimal Dosing?

    PubMed Central

    Youn, Gilmer; Jones, Brenda; Jelliffe, Roger W.; Drusano, George L.; Rodvold, Keith A.; Lodise, Thomas P.

    2014-01-01

    The current vancomycin therapeutic guidelines recommend the use of only trough concentrations to manage the dosing of adults with Staphylococcus aureus infections. Both vancomycin efficacy and toxicity are likely to be related to the area under the plasma concentration-time curve (AUC). We assembled richly sampled vancomycin pharmacokinetic data from three studies comprising 47 adults with various levels of renal function. With Pmetrics, the nonparametric population modeling package for R, we compared AUCs estimated from models derived from trough-only and peak-trough depleted versions of the full data set and characterized the relationship between the vancomycin trough concentration and AUC. The trough-only and peak-trough depleted data sets underestimated the true AUCs compared to the full model by a mean (95% confidence interval) of 23% (11 to 33%; P = 0.0001) and 14% (7 to 19%; P < 0.0001), respectively. In contrast, using the full model as a Bayesian prior with trough-only data allowed 97% (93 to 102%; P = 0.23) accurate AUC estimation. On the basis of 5,000 profiles simulated from the full model, among adults with normal renal function and a therapeutic AUC of ≥400 mg · h/liter for an organism for which the vancomycin MIC is 1 mg/liter, approximately 60% are expected to have a trough concentration below the suggested minimum target of 15 mg/liter for serious infections, which could result in needlessly increased doses and a risk of toxicity. Our data indicate that adjustment of vancomycin doses on the basis of trough concentrations without a Bayesian tool results in poor achievement of maximally safe and effective drug exposures in plasma and that many adults can have an adequate vancomycin AUC with a trough concentration of <15 mg/liter. PMID:24165176

  14. Is clinical measurement of anatomic axis of the femur adequate?

    PubMed

    Wu, Chi-Chuan

    2017-03-23

    Background and purpose - The accuracy of using clinical measurement from the anterior superior iliac spine (ASIS) to the center of the knee to determine an anatomic axis of the femur has rarely been studied. A radiographic technique with a full-length standing scanogram (FLSS) was used to assess the adequacy of the clinical measurement. Patients and methods - 100 consecutive young adult patients (mean age 34 (20-40) years) with chronic unilateral lower extremity injuries were studied. The pelvis and intact contralateral lower extremity images in the FLSS were selected for study. The angles between the tibial axis and the femoral shaft anatomic axis (S-AA), the piriformis anatomic axis (P-AA), the clinical anatomic axis (C-AA), and the mechanical axis (MA) were compared between sexes. Results - Only the S-AA and C-AA angles were statistically significantly different in the 100 patients (3.6° vs. 2.8°; p = 0.03). There was a strong correlation between S-AA, P-AA, and C-AA angles (r > 0.9). The average intersecting angle between MA and S-AA in the femur in the 100 patients was 5.5°, and it was 4.8° between MA and C-AA. Interpretation - Clinical measurement of an anatomic axis from the ASIS to the center of the knee may be an adequate and acceptable method to determine lower extremity alignment. The optimal inlet for antegrade femoral intramedullary nailing may be the lateral edge of the piriformis fossa.

  15. Oxygen distribution and consumption within the retina in vascularised and avascular retinas and in animal models of retinal disease.

    PubMed

    Yu, D Y; Cringle, S J

    2001-03-01

    Maintenance of an adequate oxygen supply to the retina is critical for retinal function. In species with vascularised retinas, such as man, oxygen is delivered to the retina via a combination of the choroidal vascular bed, which lies immediately behind the retina, and the retinal vasculature, which lies within the inner retina. The high-oxygen demands of the retina, and the relatively sparse nature of the retinal vasculature, are thought to contribute to the particular vulnerability of the retina to vascular disease. A large proportion of retinal blindness is associated with diseases having a vascular component, and disrupted oxygen supply to the retina is likely to be a critical factor. Much attention has therefore been directed at determining the intraretinal oxygen environment in healthy and diseased eyes. Measurements of oxygen levels within the retina have largely been restricted to animal studies in which oxygen sensitive microelectrodes can be used to obtain high-resolution measurements of oxygen tension as a function of retinal depth. Such measurements can immediately identify which retinal layers are supplied with oxygen from the different vascular elements. Additionally, in the outer retinal layers, which do not have any intrinsic oxygen sources, the oxygen distribution can be analysed mathematically to quantify the oxygen consumption rate of specific retinal layers. This has revealed a remarkable heterogeneity of oxygen requirements of different components of the outer retina, with the inner segments of the photoreceptors being the dominant oxygen consumers. Since the presence of the retinal vasculature precludes such a simple quantitative analysis of local oxygen consumption within the inner retina, our understanding of the oxygen needs of the inner retinal components is much less complete. Although several lines of evidence suggest that in the more commonly studied species such as cat, pig, and rat, the oxygen demands of the inner retina as a whole is

  16. Application of oxygen-enriched combustion for locomotive diesel engines. Phase 1

    SciTech Connect

    Poola, R.B.; Sekar, R.R.; Assanis, D.N.

    1996-09-01

    A thermodynamic simulation is used to study the effects of oxygen-enriched intake air on the performance and nitrogen oxide (NO) emissions of a locomotive diesel engine. The parasitic power of the air separation membrane required to supply the oxygen-enriched air is also estimated. For a given constraint on peak cylinder pressure, the gross and net power outputs of an engine operating under different levels of oxygen enrichment are compared with those obtained when a high-boost turbocharged engine is used. A 4% increase in peak cylinder pressure can result in an increase in net engine power of approximately 13% when intake air with an oxygen content of 28% by volume is used and fuel injection timing is retarded by 4 degrees. When the engine is turbocharged to a higher inlet boost, the same increase in peak cylinder pressure improves power by only 4%. If part of the significantly higher exhaust enthalpies available as a result of oxygen enrichment are recovered, the power requirements of the air separator membrane can be met, resulting in substantial net power improvements. Oxygen enrichment reduces particulate and visible smoke emissions but increases NO emissions. However, a combination of retarded fuel injection timing and post-treatment of exhaust gases may be adequate to meet the locomotive diesel engine NO{sub x} standards. Exhaust gas after-treatment and heat recovery would be required to realize the full potential of oxygen enrichment. Economic analysis shows that oxygen-enrichment technology is economically feasible and provides high returns on investment. The study also indicates the strong influence of membrane parasitic requirements and exhaust energy recovery on economic benefits. To obtain an economic advantage while using a membrane with higher parasitic power requirements, it is necessary to recover a part of the exhaust energy.

  17. An experimental study of air entrainment and oxygen transfer at a water jet from a nozzle with air holes.

    PubMed

    Baylar, Ahmet; Emiroglu, M Emin

    2004-01-01

    An adequate supply of dissolved oxygen is important in natural rivers and in some water treatment processes. The dissolved oxygen concentration can be enhanced by entraining air bubbles in a receiving pool. When a water jet impinges a receiving pool at rest, air bubbles may be entrained and carried away below the pool free surface. This process is called plunging water jet entrainment and aeration. This paper describes an experimental study of the air entrainment rate and oxygen transfer efficiency of circular nozzles with and without air holes. In particular, the effect of varying the number, positions, and open/close status of the air holes is investigated. A negative pressure occurred depending on the air holes opened on the circular nozzles. This phenomenon affected the water jet expansion, water jet shape, air entrainment, and bubble penetration depth and, hence, the oxygen transfer efficiency. It was demonstrated that the air entrainment rate and the oxygen transfer efficiency of the circular nozzles with air holes were better than those of the circular nozzles without air holes. Therefore, adding air holes to a simple, circular nozzle could lead to a significantly increased air entrainment rate and oxygen transfer efficiency.

  18. Optical oxygen concentration monitor

    DOEpatents

    Kebabian, Paul

    1997-01-01

    A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen's A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest.

  19. Petroleum supply monthly, with data from June 1996

    SciTech Connect

    1996-08-01

    The Petroleum Supply Division (PSD) of the Energy Information Administration (EIA) collects and published information on petroleum supply and disposition in the United States. The information is collected through a series of surveys that make up the Petroleum Supply Reporting System (PSRS). The PSRS data are published in the Weekly Petroleum Status Report (WPSR), Petroleum Supply Monthly (PSM), and Petroleum Supply Annual (PSA). This report presents information on crude oil production, crude oil imports and exports, refinery operations, natural gas processing, transportation, and oxygenate data.

  20. [Fire by spontaneous combustion of oxygen cylinders].

    PubMed

    Coumans, Tanja; Maissan, Iscander M; Wolff, André P; Stolker, Robert Jan; Damen, Johan; Scheffer, Gert Jan

    2010-01-01

    The use of medicinal oxygen can be dangerous. The spontaneous combustion of an oxygen cylinder was the cause of a fire in an operating theatre and an emergency medical service. The fire developed after turning on the gas main while the flow supply valve was already open. Not opening the pressure reduction valve while the oxygen flow supply valve is open can prevent this type of fire. Information from the contractor shows that the probability of such an incident is 1 in a million.

  1. Oxygen safety

    MedlinePlus

    ... with electric motors Electric baseboard or space heaters Wood stoves, fireplaces, candles Electric blankets Hairdryers, electric razors, ... Therapy.aspx . Accessed February 9, 2016. National Fire Protection Association. Medical oxygen. Updated July 2013. www.nfpa. ...

  2. Development of a model to determine oxygen consumption when crawling.

    PubMed

    Pollard, J P; Heberger, J R; Dempsey, P G

    During a mine disaster or emergency, underground air can quickly become contaminated. In these circumstances, all underground mine workers are taught to don breathable air supply units at the first sign of an emergency. However, no contemporary oxygen consumption data is available for the purposes of designing breathing air supply equipment specifically for mine escape. Further, it would be useful to quantify the oxygen requirements of breathing air supply users for various escape scenarios. To address this need, 14 participants crawled a distance of 305 m each while their breath-by-breath oxygen consumption measurements were taken. Using these data, linear regression models were developed to determine peak and average oxygen consumption rates as well as total oxygen consumption. These models can be used by manufacturers of breathing air supply equipment to aid in the design of devices that would be capable of producing sufficient on-demand oxygen to allow miners to perform self-escape.

  3. Development of a model to determine oxygen consumption when crawling

    PubMed Central

    Pollard, J.P.; Heberger, J.R.; Dempsey, P.G.

    2016-01-01

    During a mine disaster or emergency, underground air can quickly become contaminated. In these circumstances, all underground mine workers are taught to don breathable air supply units at the first sign of an emergency. However, no contemporary oxygen consumption data is available for the purposes of designing breathing air supply equipment specifically for mine escape. Further, it would be useful to quantify the oxygen requirements of breathing air supply users for various escape scenarios. To address this need, 14 participants crawled a distance of 305 m each while their breath-by-breath oxygen consumption measurements were taken. Using these data, linear regression models were developed to determine peak and average oxygen consumption rates as well as total oxygen consumption. These models can be used by manufacturers of breathing air supply equipment to aid in the design of devices that would be capable of producing sufficient on-demand oxygen to allow miners to perform self-escape. PMID:26997858

  4. Feedstock Supply System Logistics

    SciTech Connect

    2006-06-01

    Feedstock supply is a significant cost component in the production of biobased fuels, products, and power. The uncertainty of the biomass feedstock supply chain and associated risks are major barriers to procuring capital funding for start-up biorefineries.

  5. [The global and national context regarding the challenges involved in ensuring adequate access to water for human consumption].

    PubMed

    Augusto, Lia Giraldo da Silva; Gurgel, Idê Gomes Dantas; Câmara Neto, Henrique Fernandes; de Melo, Carlos Henrique; Costa, André Monteiro

    2012-06-01

    The scope of this article is to analyze the challenges involved in ensuring access to water for human consumption taking the international and national context into consideration. Based on the UN declaration that access to safe and clean drinking water is a fundamental human right, vulnerabilities are identified that can consist in restrictions to access to adequate supplies. The distribution of water and the population across the planet, pollution, inadequate policies and management lead to environmental injustice. The iniquity of access to water constitutes the contemporary water crisis. From the 1980s onwards, the transnational water market emerged for private control that occurs at three main levels: surface and underground water sources; bottled water; and public water supply services. The conflicts of the multiple uses of water resources, the market and environmental problems have contributed to rendering the health of the population and ecosystems vulnerable. Adequate public policies are essential to ensure the basic human right to access to safe and clean drinking water.

  6. Pursuing supply chain gains.

    PubMed

    Long, Gene

    2005-09-01

    Five hallmarks of an effective supply chain are: A strong relationship is developed with a single GPO. Physicians are involved in supply standardization. Supply contracts are routinely reviewed at time of renewal. Freight costs are understood and negotiated effectively. Products are distributed through an in-house distribution center.

  7. Controlling supply expenses through capitated supply contracting.

    PubMed

    Kowalski, J C

    1997-07-01

    Some providers dealing with the financial challenges of managed care are attempting to control supply expenses through capitated supply contracting and similar risk/reward sharing arrangements. Under such arrangements, a supplier sells products and services to a provider for a fixed, prospective price in exchange for the provider's exclusive business. If expenses exceed the prospectively established amount, the supplier and provider share the loss. Conversely, if expenses are less than the fixed amount, they share the savings. For a capitated supply arrangement to be successful, providers must be able to identify and track supply expense drivers, such as clinical pathways, technology utilization, and product selection and utilization. Sophisticated information systems are needed to capture data, such as total and per-transaction product usage/volume; unit price per item; average and cost per item; average and total cost per transaction; and total cost per outcome. Providers also will need to establish mutually cooperative relationships with the suppliers with whom they contract.

  8. The placental pursuit for an adequate oxidant balance between the mother and the fetus

    PubMed Central

    Herrera, Emilio A.; Krause, Bernardo; Ebensperger, German; Reyes, Roberto V.; Casanello, Paola; Parra-Cordero, Mauro; Llanos, Anibal J.

    2014-01-01

    The placenta is the exchange organ that regulates metabolic processes between the mother and her developing fetus. The adequate function of this organ is clearly vital for a physiologic gestational process and a healthy baby as final outcome. The umbilico-placental vasculature has the capacity to respond to variations in the materno-fetal milieu. Depending on the intensity and the extensity of the insult, these responses may be immediate-, mediate-, and long-lasting, deriving in potential morphostructural and functional changes later in life. These adjustments usually compensate the initial insults, but occasionally may switch to long-lasting remodeling and dysfunctional processes, arising maladaptation. One of the most challenging conditions in modern perinatology is hypoxia and oxidative stress during development, both disorders occurring in high-altitude and in low-altitude placental insufficiency. Hypoxia and oxidative stress may induce endothelial dysfunction and thus, reduction in the perfusion of the placenta and restriction in the fetal growth and development. This Review will focus on placental responses to hypoxic conditions, usually related with high-altitude and placental insufficiency, deriving in oxidative stress and vascular disorders, altering fetal and maternal health. Although day-to-day clinical practice, basic and clinical research are clearly providing evidence of the severe impact of oxygen deficiency and oxidative stress establishment during pregnancy, further research on umbilical and placental vascular function under these conditions is badly needed to clarify the myriad of questions still unsettled. PMID:25009498

  9. Report on ISS Oxygen Production, Resupply, and Partial Pressure Management

    NASA Technical Reports Server (NTRS)

    Schaezler, Ryan; Ghariani, Ahmed; Leonard, Daniel; Lehman, Daniel

    2011-01-01

    The majority of oxygen used on International Space Station (ISS) is for metabolic support and denitrogenation procedures prior to Extra-Vehicular Activities. Oxygen is supplied by various visiting vehicles such as the Progress and Shuttle in addition to oxygen production capability on both the United States On-Orbit Segment (USOS) and Russian Segment (RS). To maintain a habitable atmosphere the oxygen partial pressure is controlled between upper and lower bounds. The full range of the allowable oxygen partial pressure along with the increased ISS cabin volume is utilized as a buffer allowing days to pass between oxygen production or direct addition of oxygen to the atmosphere from reserves. This paper summarizes amount of oxygen supplied and produced from all of the sources and describes past experience of managing oxygen partial pressure along with the range of management options available to the ISS.

  10. Oxygen Therapy

    MedlinePlus

    ... also depends on where you live, your electrical supply, how active you are, cost to you and insurance restrictions. Online Version Updated April 2016 Am J Respir Crit Care Med Vol 171. P1-P2, 2005 ATS Patient Education Series © 2016 American Thoracic Society www. thoracic. org ...

  11. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  12. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  13. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  14. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  15. 21 CFR 801.5 - Medical devices; adequate directions for use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical devices; adequate directions for use. 801... (CONTINUED) MEDICAL DEVICES LABELING General Labeling Provisions § 801.5 Medical devices; adequate directions for use. Adequate directions for use means directions under which the layman can use a device...

  16. Inner retinal metabolic rate of oxygen by oxygen tension and blood flow imaging in rat.

    PubMed

    Wanek, Justin; Teng, Pang-Yu; Albers, John; Blair, Norman P; Shahidi, Mahnaz

    2011-09-01

    The metabolic function of inner retinal cells relies on the availability of nutrients and oxygen that are supplied by the retinal circulation. Assessment of retinal tissue vitality and function requires knowledge of both the rate of oxygen delivery and consumption. The purpose of the current study is to report a novel technique for assessment of the inner retinal metabolic rate of oxygen (MO(2)) by combined measurements of retinal blood flow and vascular oxygen tension (PO(2)) in rat. The application of this technology has the potential to broaden knowledge of retinal oxygen dynamics and advance understanding of disease pathophysiology.

  17. Survey of the market, supply and availability of gallium

    SciTech Connect

    Rosi, F.D.

    1980-07-01

    The objective of this study was to assess the present consumption and supply of gallium, its potential availability in the satellite power system (SPS) implementation time frame, and commercial and new processing methods for increasing the production of gallium. Findings are reported in detail. The findings strongly suggest that with proper long range planning adequate gallium would be available from free-enterprise world supplies of bauxite for SPS implementation.

  18. Academic food-supply veterinarians: future demand and likely shortages.

    PubMed

    Bruce Prince, J; Andrus, David M; Gwinner, Kevin

    2006-01-01

    The future demand for and potential shortages of food-supply veterinarians have been the subject of much concern. Using the Delphi forecasting method in a three-phase Web-based survey process, a panel of experts identified the trends and issues shaping the demand for and supply of academic food-animal veterinarians, then forecasted the likely future demand and shortages of food-supply veterinarians employed in academic institutions in the United States and Canada through 2016. The results indicate that there will be increasing future demand and persistent shortages of academic food-supply veterinarians unless current trends are countered with targeted, strategic action. The Delphi panel also evaluated the effectiveness of several strategies for reversing current trends and increasing the number of food-supply veterinarians entering into academic careers. Academic food-supply veterinarians are a key link in the system that produces food-supply veterinarians for all sectors (private practice, government service, etc.); shortages in the academic sector will amplify shortages wherever food-supply veterinarians are needed. Even fairly small shortages have significant public-health, food-safety, animal-welfare, and bio-security implications. Recent events demonstrate that in an increasingly interconnected global economic food supply system, national economies and public health are at risk unless an adequate supply of appropriately trained food-supply veterinarians is available to counter a wide variety of threats ranging from animal and zoonotic diseases to bioterrorism.

  19. Drivers of summer oxygen depletion in the central North Sea

    NASA Astrophysics Data System (ADS)

    Queste, B. Y.; Fernand, L.; Jickells, T. D.; Heywood, K. J.; Hind, A. J.

    2015-06-01

    In stratified shelf seas, oxygen depletion beneath the thermocline is a result of a greater rate of biological oxygen demand than the rate of supply of oxygenated water. Suitably equipped gliders are uniquely placed to observe both the supply through the thermocline and the consumption of oxygen in the bottom layers. A Seaglider was deployed in the shallow (≈ 100 m) stratified North Sea in a region of known low oxygen during August 2011 to investigate the processes regulating supply and consumption of dissolved oxygen below the pycnocline. The first deployment of such a device in this area, it provided extremely high resolution observations, 316 profiles (every 16 min, vertical resolution of 1 m) of CTD, dissolved oxygen concentrations, backscatter and fluorescence during a three day deployment. The high temporal resolution observations revealed occasional small scale events that supply oxygenated water into the bottom layer at a rate of 2±1 μmol dm-3 day-1. Benthic and pelagic oxygen sinks, quantified through glider observations and past studies, indicate more gradual background consumption rates of 2.5±1 μmol dm-3 day-1. This budget revealed that the balance of oxygen supply and demand is in agreement with previous studies of the North Sea. However, the glider data show a net oxygen consumption rate of 2.8±0.3 μmol dm-3 day-1 indicating a localised or short-lived increase in oxygen consumption rates. This high rate of oxygen consumption is indicative of an unidentified oxygen sink. We propose that this elevated oxygen consumption is linked to localised depocentres and rapid remineralisation of resuspensded organic matter. The glider proved to be an excellent tool for monitoring shelf sea processes despite challenges to glider flight posed by high tidal velocities, shallow bathymetry, and very strong density gradients. The direct observation of these processes allows more up to date rates to be used in the development of ecosystem models.

  20. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries

    PubMed Central

    Ryu, Won-Hee; Gittleson, Forrest S.; Thomsen, Julianne M.; Li, Jinyang; Schwab, Mark J.; Brudvig, Gary W.; Taylor, André D.

    2016-01-01

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. However, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. Here, we show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme's oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. This study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage. PMID:27759005

  1. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries

    NASA Astrophysics Data System (ADS)

    Ryu, Won-Hee; Gittleson, Forrest S.; Thomsen, Julianne M.; Li, Jinyang; Schwab, Mark J.; Brudvig, Gary W.; Taylor, André D.

    2016-10-01

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. However, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. Here, we show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme's oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. This study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.

  2. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries.

    PubMed

    Ryu, Won-Hee; Gittleson, Forrest S; Thomsen, Julianne M; Li, Jinyang; Schwab, Mark J; Brudvig, Gary W; Taylor, André D

    2016-10-19

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. However, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. Here, we show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme's oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. This study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.

  3. Oxygen: the poison is in the dose.

    PubMed

    Winslow, Robert M

    2013-02-01

    Cell-free hemoglobin (Hb) has been blamed for a spectrum of problems, including vasoconstriction pancreatitis, myocardial infarction, and pulmonary hypertension in hemolytic anemia, malaria, and sickle cell anemia, and from Hb-based oxygen carriers (HBOCs). Toxicities have been attributed to scavenging of nitric oxide (NO). However, while NO scavenging may explain many in vitro effects, and some effects in animal models and clinical trials with HBOCs, key inconsistencies in the theory require alternative explanations. This review considers the hypothesis that cell-free Hb oversupplies oxygen to tissues, leading to oxygen-related toxicity, possibly through formation of reactive oxygen species and local destruction of NO. Evidence for this hypothesis comes from various sources, establishing that tissue oxygen levels are maintained over very narrow (and low) levels, even at high oxygen consumption. Tissue is normally protected from excessive oxygen by its extremely low solubility in plasma, but introduction of cell-free Hb, even at low concentration, greatly augments oxygen supply, engaging protective mechanisms that include vasoconstriction and ischemia. The requirement to limit oxygen supply by cell-free Hb suggests novel ways to modify it to overcome vasoconstriction, independent of the intrinsic reaction of Hb with NO. This control is essential to the design of a safe and effective cell-free HBOC.

  4. OXYGEN ABUNDANCES IN CEPHEIDS

    SciTech Connect

    Luck, R. E.; Andrievsky, S. M.; Korotin, S. N.; Kovtyukh, V. V. E-mail: serkor@skyline.od.ua E-mail: scan@deneb1.odessa.ua

    2013-07-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  5. Competing for supply.

    PubMed

    Stolle, B

    2001-02-01

    The Internet was supposed to make it possible for anybody anywhere to get anything anytime. Instead, it's magnified suppliers' miscalculations into global shortages. But if the Net caused these supply chain woes, it's also the solution, says the CEO of a supply-chain software manufacturer.

  6. The Effects of Postoperative Activity on Subcuranious Tissue Oxygen Tension and Blood Flow in Orthopedic Surgical Patients

    DTIC Science & Technology

    1993-06-01

    killing common surgical infection organisms as Staphylococcus aureus, E coli, Serratia marcescens, Klebsiella pneumoniae, Proteus vulgaris , and...healing of wounded tissue is the maintenance of adequate tissue oxygenation. Abundant molecular oxygen must be present for cellular processes of oxidative

  7. Reversible Oxygenation of Oxygen Transport Proteins.

    ERIC Educational Resources Information Center

    Drain, C. M.; Corden, Barry B.

    1987-01-01

    Describes a lecture demonstration which illustrates changes in the visible spectra of oxygen transport proteins upon reversible oxygen binding. Provides a comparison of the physical characteristics of oxygen storage and transport proteins. Reviews essentials for preparation of the materials. (ML)

  8. Power supply conditioning circuit

    NASA Technical Reports Server (NTRS)

    Primas, L. E.; Loveland, R.

    1987-01-01

    A power supply conditioning circuit that can reduce Periodic and Random Deviations (PARD) on the output voltages of dc power supplies to -150 dBV from dc to several KHz with no measurable periodic deviations is described. The PARD for a typical commercial low noise power supply is -74 dBV for frequencies above 20 Hz and is often much worse at frequencies below 20 Hz. The power supply conditioning circuit described here relies on the large differences in the dynamic impedances of a constant current diode and a zener diode to establish a dc voltage with low PARD. Power supplies with low PARD are especially important in circuitry involving ultrastable frequencies for the Deep Space Network.

  9. Spatial Data Supply Chains

    NASA Astrophysics Data System (ADS)

    Varadharajulu, P.; Azeem Saqiq, M.; Yu, F.; McMeekin, D. A.; West, G.; Arnold, L.; Moncrieff, S.

    2015-06-01

    This paper describes current research into the supply of spatial data to the end user in as close to real time as possible via the World Wide Web. The Spatial Data Infrastructure paradigm has been discussed since the early 1990s. The concept has evolved significantly since then but has almost always examined data from the perspective of the supplier. It has been a supplier driven focus rather than a user driven focus. The current research being conducted is making a paradigm shift and looking at the supply of spatial data as a supply chain, similar to a manufacturing supply chain in which users play a significant part. A comprehensive consultation process took place within Australia and New Zealand incorporating a large number of stakeholders. Three research projects that have arisen from this consultation process are examining Spatial Data Supply Chains within Australia and New Zealand and are discussed within this paper.

  10. Petroleum supply annual 1994, Volume 2

    SciTech Connect

    1995-06-01

    The Petroleum Supply Annual (PSA) contains information on the supply and disposition of crude oil and petroleum products. The publication reflects data that were collected from the petroleum industry during 1994 through annual and monthly surveys. The PSA is divided into two volumes. This first volume contains four sections: Summary Statistics, Detailed Statistics, Refinery Capacity, and Oxygenate Capacity each with final annual data. The second volume contains final statistics for each month of 1994, and replaces data previously published in the Petroleum Supply Monthly (PSM). The tables in Volumes 1 and 2 are similarly numbered to facilitate comparison between them. Explanatory Notes, located at the end of this publication, present information describing data collection, sources, estimation methodology, data quality control procedures, modifications to reporting requirements and interpretation of tables. Industry terminology and product definitions are listed alphabetically in the Glossary.

  11. The Human Right to Adequate Housing: A Tool for Promoting and Protecting Individual and Community Health

    PubMed Central

    Thiele, Bret

    2002-01-01

    The human right to adequate housing is enshrined in international law. The right to adequate housing can be traced to the Universal Declaration of Human Rights, which was unanimously adopted by the world community in 1948. Since that time, the right to adequate housing has been reaffirmed on numerous occasions and further defined and elaborated. A key component of this right is habitability of housing, which should comply with health and safety standards. Therefore, the right to adequate housing provides an additional tool for advocates and others interested in promoting healthful housing and living conditions and thereby protecting individual and community health. PMID:11988432

  12. Quadriceps oxygenation changes during walking and running on a treadmill

    NASA Astrophysics Data System (ADS)

    Quaresima, Valentina; Pizzi, Assunta; De Blasi, Roberto A.; Ferrari, Adriano; de Angelis, Marco; Ferrari, Marco

    1995-04-01

    Vastus lateralis muscle oxygenation was investigated on volunteers as well as muscular dystrophy patients during a walking test, and on volunteers during a free running by a continuous wave near infrared instrument. The data were analyzed using an oxygenation index independent on pathlength changes. Walking did not significantly affect the oxygenation of volunteers and patients. A relative deoxygenation was found only during free running indicating an unbalance between oxygen supply and tissue oxygen extraction. Preliminary measurements of exercising muscle oxygen saturation were performed by a 110 MHz frequency-domain, multisource instrument.

  13. 14 CFR 25.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Equipment standards for oxygen dispensing... § 25.1447 Equipment standards for oxygen dispensing units. If oxygen dispensing units are installed... supplemental oxygen is to be supplied. Units must be designed to cover the nose and mouth and must be...

  14. 14 CFR 25.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Equipment standards for oxygen dispensing... § 25.1447 Equipment standards for oxygen dispensing units. If oxygen dispensing units are installed... supplemental oxygen is to be supplied. Units must be designed to cover the nose and mouth and must be...

  15. 14 CFR 25.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Equipment standards for oxygen dispensing... § 25.1447 Equipment standards for oxygen dispensing units. If oxygen dispensing units are installed... supplemental oxygen is to be supplied. Units must be designed to cover the nose and mouth and must be...

  16. 14 CFR 23.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Equipment standards for oxygen dispensing... Equipment Miscellaneous Equipment § 23.1447 Equipment standards for oxygen dispensing units. If oxygen... occupant for whom supplemental oxygen is to be supplied. Each dispensing unit must: (1) Provide...

  17. 14 CFR 25.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Equipment standards for oxygen dispensing... § 25.1447 Equipment standards for oxygen dispensing units. If oxygen dispensing units are installed... supplemental oxygen is to be supplied. Units must be designed to cover the nose and mouth and must be...

  18. 14 CFR 23.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Equipment standards for oxygen dispensing... Equipment Miscellaneous Equipment § 23.1447 Equipment standards for oxygen dispensing units. If oxygen... occupant for whom supplemental oxygen is to be supplied. Each dispensing unit must: (1) Provide...

  19. 14 CFR 25.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Equipment standards for oxygen dispensing... § 25.1447 Equipment standards for oxygen dispensing units. If oxygen dispensing units are installed... supplemental oxygen is to be supplied. Units must be designed to cover the nose and mouth and must be...

  20. 14 CFR 23.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Equipment standards for oxygen dispensing... Equipment Miscellaneous Equipment § 23.1447 Equipment standards for oxygen dispensing units. If oxygen... occupant for whom supplemental oxygen is to be supplied. Each dispensing unit must: (1) Provide...

  1. 14 CFR 23.1447 - Equipment standards for oxygen dispensing units.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Equipment standards for oxygen dispensing... Equipment Miscellaneous Equipment § 23.1447 Equipment standards for oxygen dispensing units. If oxygen... occupant for whom supplemental oxygen is to be supplied. Each dispensing unit must: (1) Provide...

  2. Hydrogen supply system

    SciTech Connect

    Teitel, R.J.

    1981-11-24

    A system for supplying hydrogen to an apparatus which utilizes hydrogen contains a metal hydride hydrogen supply component and a microcavity hydrogen storage hydrogen supply component which in tandem supply hydrogen for the apparatus. The metal hydride hydrogen supply component includes a first storage tank filled with a composition which is capable of forming a metal hydride of such a nature that the hydride will release hydrogen when heated but will absorb hydrogen when cooled. This first storage tank is equipped with a heat exchanger for both adding heat to and extracting heat from the composition to regulate the absorption/deabsorption of hydrogen from the composition. The microcavity hydrogen storage hydrogen supply component includes a second tank containing the microcavity hydrogen supply. The microcavity hydrogen storage contains hydrogen held under high pressure within individual microcavities. The hydrogen is released from the microcavities by heating the cavities. This heating is accomplished by including within the tank for the microcavity hydrogen storage a heating element.

  3. Automating power supply checkout

    SciTech Connect

    Laster, J.; Bruno, D.; D'Ottavio, T.; Drozd, J.; Marr, G.; Mi, C.

    2011-03-28

    Power Supply checkout is a necessary, pre-beam, time-critical function. At odds are the desire to decrease the amount of time to perform the checkout while at the same time maximizing the number and types of checks that can be performed and analyzing the results quickly (in case any problems exist that must be addressed). Controls and Power Supply Group personnel have worked together to develop tools to accomplish these goals. Power Supply checkouts are now accomplished in a time-frame of hours rather than days, reducing the number of person-hours needed to accomplish the checkout and making the system available more quickly for beam development. The goal of the Collider-Accelerator Department (CAD) at Brookhaven National Laboratory is to provide experimenters with collisions of heavy-ions and polarized protons. The Relativistic Heavy-Ion Collider (RHIC) magnets are controlled by 100's of varying types of power supplies. There is a concentrated effort to perform routine maintenance on the supplies during shutdown periods. There is an effort at RHIC to streamline the time needed for system checkout in order to quickly arrive at a period of beam operations for RHIC. This time-critical period is when the checkout of the power supplies is performed as the RHIC ring becomes cold and the supplies are connected to their physical magnets. The checkout process is used to identify problems in voltage and current regulation by examining data signals related to each for problems in settling and regulation (ripple).

  4. Supply chain planning classification

    NASA Astrophysics Data System (ADS)

    Hvolby, Hans-Henrik; Trienekens, Jacques; Bonde, Hans

    2001-10-01

    Industry experience a need to shift in focus from internal production planning towards planning in the supply network. In this respect customer oriented thinking becomes almost a common good amongst companies in the supply network. An increase in the use of information technology is needed to enable companies to better tune their production planning with customers and suppliers. Information technology opportunities and supply chain planning systems facilitate companies to monitor and control their supplier network. In spite if these developments, most links in today's supply chains make individual plans, because the real demand information is not available throughout the chain. The current systems and processes of the supply chains are not designed to meet the requirements now placed upon them. For long term relationships with suppliers and customers, an integrated decision-making process is needed in order to obtain a satisfactory result for all parties. Especially when customized production and short lead-time is in focus. An effective value chain makes inventory available and visible among the value chain members, minimizes response time and optimizes total inventory value held throughout the chain. In this paper a supply chain planning classification grid is presented based current manufacturing classifications and supply chain planning initiatives.

  5. Supply chain assessment methodology.

    PubMed

    Topor, E

    2000-08-01

    This article describes an assessment methodology based on the supply chain proficiency model that can be used to set realistic supply chain objectives. The assessment centers on a business model that identifies the logical stages of supply chain proficiency as measured against a comprehensive set of business characteristics. For each characteristic, an enterprise evolves from one stage to the next. The magnitude of change inherent in moving forward usually prohibits skipping stages. Although it is possible to be at different stages for each characteristic, it is usually desirable to maintain balance.

  6. Simultaneous monitoring of tissue P2 and NADH fluorescence during synaptic stimulation and spreading depression reveals a transient dissociation between oxygen utilization and mitochondrial redox state in rat hippocampal slices

    PubMed Central

    Galeffi, Francesca; Somjen, George G; Foster, Kelley A; Turner, Dennis A

    2011-01-01

    Nicotinamide adenine dinucleotide (NADH) imaging can be used to monitor neuronal activation and ascertain mitochondrial dysfunction, for example during hypoxia. During neuronal stimulation in vitro, NADH normally becomes more oxidized, indicating enhanced oxygen utilization. A subsequent NADH overshoot during activation or on recovery remains controversial and reflects either increased metabolic activity or limited oxygen availability. Tissue P2 measurements, obtained simultaneously with NADH imaging in area CA1 in hippocampal slices, reveal that during prolonged train stimulation (ST) in 95% O2, a persistent NADH oxidation is coupled with increased metabolic demand and oxygen utilization, for the duration of the stimulation. However, under conditions of either decreased oxygen supply (ST-50% O2) or enhanced metabolic demand (K+-induced spreading depression (K+-SD) 95% O2) the NADH oxidation is brief and the redox balance shifts early toward reduction, leading to a prolonged NADH overshoot. Yet, oxygen utilization remains elevated and is correlated with metabolic demand. Under these conditions, it appears that the rate of NAD+ reduction may transiently exceed oxidation, to maintain an adequate oxygen flux and ATP production. In contrast, during SD in 50% O2, the oxygen levels dropped to a point at which oxidative metabolism in the electron transport chain is limited and the rate of utilization declined. PMID:20736960

  7. Molecular evolution of the metazoan PHD-HIF oxygen-sensing system.

    PubMed

    Rytkönen, Kalle T; Williams, Tom A; Renshaw, Gillian M; Primmer, Craig R; Nikinmaa, Mikko

    2011-06-01

    Metazoans rely on aerobic energy production, which requires an adequate oxygen supply. During reduced oxygen supply (hypoxia), the most profound changes in gene expression are mediated by transcription factors known as hypoxia-inducible factors (HIFs). HIF alpha proteins are commonly posttranslationally regulated by prolyl-4-hydroxylase (PHD) enzymes, which are direct "sensors" of cellular oxygen levels. We examined the molecular evolution of the metazoan PHD-HIF oxygen-sensing system by constructing complete phylogenies for PHD and HIF alpha genes and used computational tools to characterize the molecular changes underlying the functional divergence of PHD and HIF alpha duplicates. The presence of PHDs in metazoan genomes predates the emergence of HIF alphas. Our analysis revealed an unexpected diversity of PHD genes and HIF alpha sequence characteristics in invertebrates, suggesting that the simple oxygen-sensing systems of Caenorhabditis and Drosophila may not be typical of other invertebrate bilaterians. We studied the early vertebrate evolution of the system by sequencing these genes in early-diverging cartilaginous fishes, elasmobranchs. Cartilaginous fishes appear to have three paralogs of both PHD and HIF alpha. The novel sequences were used as outgroups for a detailed molecular analysis of PHD and HIF alpha duplicates in a major air-breathing vertebrate lineage, the mammals, and a major water-breathing vertebrate lineage, the teleosts. In PHDs, functionally divergent amino acid sites were detected near the HIF alpha-binding channel and beta2beta3 loop that defines its substrate specificity. In HIF alphas, more functional divergence was found in teleosts than in mammals, especially in the HIF-1 alpha PAS domain and HIF-2 alpha oxygen-dependent degradation (ODD) domains, which interact with PHDs. Overall, in the vertebrates, elevated substitution rates in the HIF-2 alpha N-terminal ODD domain, together with a functional divergence associated with the known

  8. On the adhesion-cohesion balance and oxygen consumption characteristics of liver organoids

    PubMed Central

    Mattei, Giorgio; Magliaro, Chiara; Giusti, Serena; Ramachandran, Sarada Devi; Heinz, Stefan; Braspenning, Joris; Ahluwalia, Arti

    2017-01-01

    Liver organoids (LOs) are of interest in tissue replacement, hepatotoxicity and pathophysiological studies. However, it is still unclear what triggers LO self-assembly and what the optimal environment is for their culture. Hypothesizing that LO formation occurs as a result of a fine balance between cell-substrate adhesion and cell-cell cohesion, we used 3 cell types (hepatocytes, liver sinusoidal endothelial cells and mesenchymal stem cells) to investigate LO self-assembly on different substrates keeping the culture parameters (e.g. culture media, cell types/number) and substrate stiffness constant. As cellular spheroids may suffer from oxygen depletion in the core, we also sought to identify the optimal culture conditions for LOs in order to guarantee an adequate supply of oxygen during proliferation and differentiation. The oxygen consumption characteristics of LOs were measured using an O2 sensor and used to model the O2 concentration gradient in the organoids. We show that no LO formation occurs on highly adhesive hepatic extra-cellular matrix-based substrates, suggesting that cellular aggregation requires an optimal trade-off between the adhesiveness of a substrate and the cohesive forces between cells and that this balance is modulated by substrate mechanics. Thus, in addition to substrate stiffness, physicochemical properties, which are also critical for cell adhesion, play a role in LO self-assembly. PMID:28267799

  9. New vessel formation in the context of cardiomyocyte regeneration--the role and importance of an adequate perfusing vasculature.

    PubMed

    Michelis, Katherine C; Boehm, Manfred; Kovacic, Jason C

    2014-11-01

    The history of revascularization for cardiac ischemia dates back to the early 1960's when the first coronary artery bypass graft procedures were performed in humans. With this 50 year history of providing a new vasculature to ischemic and hibernating myocardium, a profound depth of experience has been amassed in clinical cardiovascular medicine as to what does, and does not work in the context of cardiac revascularization, alleviating ischemia and adequacy of myocardial perfusion. These issues are of central relevance to contemporary cell-based cardiac regenerative approaches. While the cardiovascular cell therapy field is surging forward on many exciting fronts, several well accepted clinical axioms related to the cardiac arterial supply appear to be almost overlooked by some of our current basic conceptual and experimental cell therapy paradigms. We present here information drawn from five decades of the clinical revascularization experience, review relevant new data on vascular formation via cell therapy, and put forward the case that for optimal cell-based cardiac regeneration due attention must be paid to providing an adequate vascular supply.

  10. New vessel formation in the context of cardiomyocyte regeneration – the role and importance of an adequate perfusing vasculature

    PubMed Central

    Michelis, Katherine C.; Boehm, Manfred; Kovacic, Jason C.

    2014-01-01

    The history of revascularization for cardiac ischemia dates back to the early 1960's when the first coronary artery bypass graft procedures were performed in humans. With this 50 year history of providing a new vasculature to ischemic and hibernating myocardium, a profound depth of experience has been amassed in clinical cardiovascular medicine as to what does, and does not work in the context of cardiac revascularization, alleviating ischemia and adequacy of myocardial perfusion. These issues are of central relevance to contemporary cell-based cardiac regenerative approaches. While the cardiovascular cell therapy field is surging forward on many exciting fronts, several well accepted clinical axioms related to the cardiac arterial supply appear to be almost overlooked by some of our current basic conceptual and experimental cell therapy paradigms. We present here information drawn from five decades of the clinical revascularization experience, review relevant new data on vascular formation via cell therapy, and put forward the case that for optimal cell-based cardiac regeneration due attention must be paid to providing an adequate vascular supply. PMID:24841067

  11. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT... and Adequate Veterinary Care § 2.40 Attending veterinarian and adequate veterinary care (dealers and... veterinary care to its animals in compliance with this section. (1) Each dealer and exhibitor shall employ...

  12. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  13. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  14. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  15. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  16. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  17. 40 CFR 152.20 - Exemptions for pesticides adequately regulated by another Federal agency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Exemptions for pesticides adequately... PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS PESTICIDE REGISTRATION AND CLASSIFICATION PROCEDURES Exemptions § 152.20 Exemptions for pesticides adequately regulated by another Federal agency. The...

  18. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  19. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  20. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Adequate financial records, statistical data, and....568 Adequate financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination...

  1. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  2. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  3. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  4. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Assurances of adequate capacity and services. 438... Improvement Access Standards § 438.207 Assurances of adequate capacity and services. (a) Basic rule. The State... provides supporting documentation that demonstrates that it has the capacity to serve the...

  5. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  6. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall provide adequate veterinary care to its animals in compliance with this section: (1) Each research facility...

  7. Oxygen requirements of the earliest animals

    PubMed Central

    Mills, Daniel B.; Ward, Lewis M.; Jones, CarriAyne; Sweeten, Brittany; Forth, Michael; Treusch, Alexander H.; Canfield, Donald E.

    2014-01-01

    A rise in the oxygen content of the atmosphere and oceans is one of the most popular explanations for the relatively late and abrupt appearance of animal life on Earth. In this scenario, Earth’s surface environment failed to meet the high oxygen requirements of animals up until the middle to late Neoproterozoic Era (850–542 million years ago), when oxygen concentrations sufficiently rose to permit the existence of animal life for the first time. Although multiple lines of geochemical evidence support an oxygenation of the Ediacaran oceans (635–542 million years ago), roughly corresponding with the first appearance of metazoans in the fossil record, the oxygen requirements of basal animals remain unclear. Here we show that modern demosponges, serving as analogs for early animals, can survive under low-oxygen conditions of 0.5–4.0% present atmospheric levels. Because the last common ancestor of metazoans likely exhibited a physiology and morphology similar to that of a modern sponge, its oxygen demands may have been met well before the enhanced oxygenation of the Ediacaran Period. Therefore, the origin of animals may not have been triggered by a contemporaneous rise in the oxygen content of the atmosphere and oceans. Instead, other ecological and developmental processes are needed to adequately explain the origin and earliest evolution of animal life on Earth. PMID:24550467

  8. Oxygen requirements of the earliest animals

    NASA Astrophysics Data System (ADS)

    Mills, Daniel B.; Ward, Lewis M.; Jones, CarriAyne; Sweeten, Brittany; Forth, Michael; Treusch, Alexander H.; Canfield, Donald E.

    2014-03-01

    A rise in the oxygen content of the atmosphere and oceans is one of the most popular explanations for the relatively late and abrupt appearance of animal life on Earth. In this scenario, Earth's surface environment failed to meet the high oxygen requirements of animals up until the middle to late Neoproterozoic Era (850-542 million years ago), when oxygen concentrations sufficiently rose to permit the existence of animal life for the first time. Although multiple lines of geochemical evidence support an oxygenation of the Ediacaran oceans (635-542 million years ago), roughly corresponding with the first appearance of metazoans in the fossil record, the oxygen requirements of basal animals remain unclear. Here we show that modern demosponges, serving as analogs for early animals, can survive under low-oxygen conditions of 0.5-4.0% present atmospheric levels. Because the last common ancestor of metazoans likely exhibited a physiology and morphology similar to that of a modern sponge, its oxygen demands may have been met well before the enhanced oxygenation of the Ediacaran Period. Therefore, the origin of animals may not have been triggered by a contemporaneous rise in the oxygen content of the atmosphere and oceans. Instead, other ecological and developmental processes are needed to adequately explain the origin and earliest evolution of animal life on Earth.

  9. Oxygen requirements of the earliest animals.

    PubMed

    Mills, Daniel B; Ward, Lewis M; Jones, Carriayne; Sweeten, Brittany; Forth, Michael; Treusch, Alexander H; Canfield, Donald E

    2014-03-18

    A rise in the oxygen content of the atmosphere and oceans is one of the most popular explanations for the relatively late and abrupt appearance of animal life on Earth. In this scenario, Earth's surface environment failed to meet the high oxygen requirements of animals up until the middle to late Neoproterozoic Era (850-542 million years ago), when oxygen concentrations sufficiently rose to permit the existence of animal life for the first time. Although multiple lines of geochemical evidence support an oxygenation of the Ediacaran oceans (635-542 million years ago), roughly corresponding with the first appearance of metazoans in the fossil record, the oxygen requirements of basal animals remain unclear. Here we show that modern demosponges, serving as analogs for early animals, can survive under low-oxygen conditions of 0.5-4.0% present atmospheric levels. Because the last common ancestor of metazoans likely exhibited a physiology and morphology similar to that of a modern sponge, its oxygen demands may have been met well before the enhanced oxygenation of the Ediacaran Period. Therefore, the origin of animals may not have been triggered by a contemporaneous rise in the oxygen content of the atmosphere and oceans. Instead, other ecological and developmental processes are needed to adequately explain the origin and earliest evolution of animal life on Earth.

  10. Global Uranium And Thorium Resources: Are They Adequate To Satisfy Demand Over The Next Half Century?

    NASA Astrophysics Data System (ADS)

    Lambert, I. B.

    2012-04-01

    This presentation will consider the adequacy of global uranium and thorium resources to meet realistic nuclear power demand scenarios over the next half century. It is presented on behalf of, and based on evaluations by, the Uranium Group - a joint initiative of the OECD Nuclear Energy Agency and the International Atomic Energy Agency, of which the author is a Vice Chair. The Uranium Group produces a biennial report on Uranium Resources, Production and Demand based on information from some 40 countries involved in the nuclear fuel cycle, which also briefly reviews thorium resources. Uranium: In 2008, world production of uranium amounted to almost 44,000 tonnes (tU). This supplied approximately three-quarters of world reactor requirements (approx. 59,000 tU), the remainder being met by previously mined uranium (so-called secondary sources). Information on availability of secondary sources - which include uranium from excess inventories, dismantling nuclear warheads, tails and spent fuel reprocessing - is incomplete, but such sources are expected to decrease in market importance after 2013. In 2008, the total world Reasonably Assured plus Inferred Resources of uranium (recoverable at less than 130/kgU) amounted to 5.4 million tonnes. In addition, it is clear that there are vast amounts of uranium recoverable at higher costs in known deposits, plus many as yet undiscovered deposits. The Uranium Group has concluded that the uranium resource base is more than adequate to meet projected high-case requirements for nuclear power for at least half a century. This conclusion does not assume increasing replacement of uranium by fuels from reprocessing current reactor wastes, or by thorium, nor greater reactor efficiencies, which are likely to ameliorate future uranium demand. However, progressively increasing quantities of uranium will need to be mined, against a backdrop of the relatively small number of producing facilities around the world, geopolitical uncertainties and

  11. Managing Supply Chain Disruptions

    DTIC Science & Technology

    2008-08-09

    functions within and across organizations (CSCMP, 2005). Mentzer et al. (2001) characterize SCM as a philosophy that includes a systems approach with...150 vi LIST OF TABLES Table 2.1. Prominent Supply Chain Related System Theory...process. It is not a matter of a supply chain system encountering a problem, but rather a matter of when a problematic event will occur and how severe

  12. Comparative transcriptome analysis of Bacillus subtilis responding to dissolved oxygen in adenosine fermentation.

    PubMed

    Yu, Wen-Bang; Gao, Shu-Hong; Yin, Chun-Yun; Zhou, Ying; Ye, Bang-Ce

    2011-01-01

    Dissolved oxygen (DO) is an important factor for adenosine fermentation. Our previous experiments have shown that low oxygen supply in the growth period was optimal for high adenosine yield. Herein, to better understand the link between oxygen supply and adenosine productivity in B. subtilis (ATCC21616), we sought to systematically explore the effect of DO on genetic regulation and metabolism through transcriptome analysis. The microarrays representing 4,106 genes were used to study temporal transcript profiles of B. subtilis fermentation in response to high oxygen supply (agitation 700 r/min) and low oxygen supply (agitation 450 r/min). The transcriptome data analysis revealed that low oxygen supply has three major effects on metabolism: enhance carbon metabolism (glucose metabolism, pyruvate metabolism and carbon overflow), inhibit degradation of nitrogen sources (glutamate family amino acids and xanthine) and purine synthesis. Inhibition of xanthine degradation was the reason that low oxygen supply enhanced adenosine production. These provide us with potential targets, which can be modified to achieve higher adenosine yield. Expression of genes involved in energy, cell type differentiation, protein synthesis was also influenced by oxygen supply. These results provided new insights into the relationship between oxygen supply and metabolism.

  13. 45 CFR 1159.15 - Who has the responsibility for maintaining adequate technical, physical, and security safeguards...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... of maintaining adequate technical, physical, and security safeguards to prevent...

  14. 45 CFR 1159.15 - Who has the responsibility for maintaining adequate technical, physical, and security safeguards...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... adequate technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of... of maintaining adequate technical, physical, and security safeguards to prevent...

  15. A Cabin Air Separator for EVA Oxygen

    NASA Technical Reports Server (NTRS)

    Graf, John C.

    2011-01-01

    Presently, the Extra-Vehicular Activities (EVAs) conducted from the Quest Joint Airlock on the International Space Station use high pressure, high purity oxygen that is delivered to the Space Station by the Space Shuttle. When the Space Shuttle retires, a new method of delivering high pressure, high purity oxygen to the High Pressure Gas Tanks (HPGTs) is needed. One method is to use a cabin air separator to sweep oxygen from the cabin air, generate a low pressure/high purity oxygen stream, and compress the oxygen with a multistage mechanical compressor. A main advantage to this type of system is that the existing low pressure oxygen supply infrastructure can be used as the source of cabin oxygen. ISS has two water electrolysis systems that deliver low pressure oxygen to the cabin, as well as chlorate candles and compressed gas tanks on cargo vehicles. Each of these systems can feed low pressure oxygen into the cabin, and any low pressure oxygen source can be used as an on-board source of oxygen. Three different oxygen separator systems were evaluated, and a two stage Pressure Swing Adsorption system was selected for reasons of technical maturity. Two different compressor designs were subjected to long term testing, and the compressor with better life performance and more favorable oxygen safety characteristics was selected. These technologies have been used as the basis of a design for a flight system located in Equipment Lock, and taken to Preliminary Design Review level of maturity. This paper describes the Cabin Air Separator for EVA Oxygen (CASEO) concept, describes the separator and compressor technology trades, highlights key technology risks, and describes the flight hardware concept as presented at Preliminary Design Review (PDR)

  16. Effect of micro- and macroencapsulation on oxygen consumption by pancreatic islets.

    PubMed

    Cornolti, Roberta; Figliuzzi, Marina; Remuzzi, Andrea

    2009-01-01

    Immunoisolation of pancreatic islets is extensively investigated for glycemic control in diabetic experimental animals. We previously reported that subcutaneous xenotransplantation of bovine islets protected by a selective polysulfone membrane successfully controlled glycemia in diabetic rats for up to 20 days. We then wondered whether immunoisolated islets have adequate oxygen supply in this device, where only diffusive transport allows cell function and survival. Here we set up an experimental technique to measure oxygen consumption rate (OCR) using a Clark's electrode inserted in a glass thermostated chamber connected to a data recorder and acquisition system. Bovine islets were isolated from 6-month-old calves, encapsulated in sodium alginate microcapsules or inserted in polysulfone hollow fibers. After 1 and 2 days in culture a series of measurements was performed using free islets (at normal or high-glucose concentration), islets encapsulated in microcapsules, or in hollow fibers. In free islets OCR averaged from 2.0 +/- 0.8 pmol/IEQ/min at low-glucose concentration and from 2.5 +/- 1.0 pmol/IEQ/min at high-glucose concentration (p < 0.01). OCR in islets encapsulated in microcapsules and in hollow fibers was comparable, and not significantly different from that measured in free islets. Two days after isolation OCR averaged 2.3 +/- 0.6 in free islets, 2.3 +/- 0.9 in alginate microcapsules, and 2.2 +/- 0.7 pmol/IEQ/min in hollow fibers. These results show that OCR by bovine islets is comparable to that previously reported for other species. OCR increases in islets stimulated with high glucose and may be considered as a functional index. Moreover, islet encapsulation in alginate microcapsule, as well as in hollow fiber membranes, did not significantly affect in vitro OCR, suggesting adequate islet oxygenation in these conditions.

  17. Critical State of Energy Metabolism in Brain Slices: The Principal Role of Oxygen Delivery and Energy Substrates in Shaping Neuronal Activity

    PubMed Central

    Ivanov, Anton; Zilberter, Yuri

    2011-01-01

    The interactive vasculo-neuro-glial system controlling energy supply in the brain is absent in vitro where energy provision is determined by experimental conditions. Despite the fact that neuronal activity is extremely energy demanding, little has been reported on the state of energy metabolism in submerged brain slices. Without this information, the arbitrarily chosen oxygenation and metabolic provisions make questionable the efficient oxidative metabolism in slices. We show that in mouse hippocampal slices (postnatal day 19–44), evoked neuronal discharges, spontaneous network activity (initiated by 4-aminopyridine), and synaptic stimulation-induced NAD(P)H autofluorescence depend strongly on the oxygen availability. Only the rate of perfusion as high as ~15 ml/min (95% O2) provided appropriate oxygenation of a slice. Lower oxygenation resulted in the decrease of both local field potentials and spontaneous network activity as well as in significant modulation of short-term synaptic plasticity. The reduced oxygen supply considerably inhibited the oxidation phase of NAD(P)H signaling indicating that the changes in neuronal activity were paralleled by the decrease in aerobic energy metabolism. Interestingly, the dependence of neuronal activity on oxygen tension was clearly shifted toward considerably larger pO2 values in slices when compared to in vivo conditions. With sufficient pO2 provided by a high perfusion rate, partial substitution of glucose in ACSF for β-hydroxybutyrate, pyruvate, or lactate enhanced both oxidative metabolism and synaptic function. This suggests that the high pO2 in brain slices is compulsory for maintaining oxidative metabolism, and glucose alone is not sufficient in fulfilling energy requirements during neuronal activity. Altogether, our results demonstrate that energy metabolism determines the functional state of neuronal network, highlighting the need for the adequate metabolic support to be insured in the in vitro experiments. PMID

  18. Oxygen tension level and human viral infections.

    PubMed

    Morinet, Frédéric; Casetti, Luana; François, Jean-Hugues; Capron, Claude; Pillet, Sylvie

    2013-09-01

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition.

  19. Inferential Processing among Adequate and Struggling Adolescent Comprehenders and Relations to Reading Comprehension

    PubMed Central

    Barth, Amy E.; Barnes, Marcia; Francis, David J.; Vaughn, Sharon; York, Mary

    2015-01-01

    Separate mixed model analyses of variance (ANOVA) were conducted to examine the effect of textual distance on the accuracy and speed of text consistency judgments among adequate and struggling comprehenders across grades 6–12 (n = 1203). Multiple regressions examined whether accuracy in text consistency judgments uniquely accounted for variance in comprehension. Results suggest that there is considerable growth across the middle and high school years, particularly for adequate comprehenders in those text integration processes that maintain local coherence. Accuracy in text consistency judgments accounted for significant unique variance for passage-level, but not sentence-level comprehension, particularly for adequate comprehenders. PMID:26166946

  20. Using Multitheory Model of Health Behavior Change to Predict Adequate Sleep Behavior.

    PubMed

    Knowlden, Adam P; Sharma, Manoj; Nahar, Vinayak K

    The purpose of this article was to use the multitheory model of health behavior change in predicting adequate sleep behavior in college students. A valid and reliable survey was administered in a cross-sectional design (n = 151). For initiation of adequate sleep behavior, the construct of behavioral confidence (P < .001) was found to be significant and accounted for 24.4% of the variance. For sustenance of adequate sleep behavior, changes in social environment (P < .02), emotional transformation (P < .001), and practice for change (P < .001) were significant and accounted for 34.2% of the variance.

  1. Petroleum Supply Monthly

    SciTech Connect

    1996-02-01

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major U.S. geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blenders, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States. Data presented in the PSM are divided into two sections: Summary Statistics and Detailed Statistics.

  2. Petroleum supply monthly

    SciTech Connect

    1995-10-01

    The Petroleum Supply Monthly (PSM) is one of a family of four publications produced by the Petroleum Supply Division within the Energy Information Administration (EIA) reflecting different levels of data timeliness and completeness. The other publications are the Weekly Petroleum Status Report (WPSR), the Winter Fuels Report, and the Petroleum Supply Annual (PSA). Data presented in the PSM describe the supply and disposition of petroleum products in the United States and major US geographic regions. The data series describe production, imports and exports, inter-Petroleum Administration for Defense (PAD) District movements, and inventories by the primary suppliers of petroleum products in the United States (50 States and the District of Columbia). The reporting universe includes those petroleum sectors in primary supply. Included are: petroleum refiners, motor gasoline blends, operators of natural gas processing plants and fractionators, inter-PAD transporters, importers, and major inventory holders of petroleum products and crude oil. When aggregated, the data reported by these sectors approximately represent the consumption of petroleum products in the United States.

  3. Oxygenation of intensive cell-culture system.

    PubMed

    Emery, A N; Jan, D C; al-Rubeai, M

    1995-11-01

    The abilities of various methods of oxygenation to meet the demands of high-cell-density culture were investigated using a spin filter perfusion system in a bench-top bioreactor. Oxygen demand at high cell density could not be met by sparging with air inside a spin filter (oxygen transfer values in this condition were comparable with those for surface aeration). Sparging with air outside a spin filter gave adequate oxygen transfer for the support of cell concentrations above 10(7) ml-1 in fully aerobic conditions but the addition of antifoam to control foaming caused blockage of the spinfilter mesh. Bubble-free aeration through immersed silicone tubing with pure oxygen gave similar oxygen transfer rates to that of sparging with air but without the problems of bubble damage and fouling of the spin filter. A supra-optimal level of dissolved oxygen (478% air saturation) inhibited cell growth. However, cells could recover from this stress and reach high density after reduction of the dissolved oxygen level to 50% air saturation.

  4. OXYGEN TRANSPORT IN THE MICROCIRCULATION AND ITS REGULATION

    PubMed Central

    Pittman, Roland N.

    2012-01-01

    Cells require energy to carry out their functions and they typically use oxidative phosphorylation to generate the needed ATP. Thus, cells have a continuous need for oxygen which they receive by diffusion from the blood through the interstitial fluid. The circulatory system pumps oxygen-rich blood through a network of increasingly minute vessels, the microcirculation. The structure of the microcirculation is such that all cells have at least one nearby capillary for diffusive exchange of oxygen and red blood cells release the oxygen bound to hemoglobin as they traverse capillaries. This review focuses first on the historical development of techniques to measure oxygen at various sites in the microcirculation, including the blood, interstitium and cells. Next, approaches are described as to how these techniques have been employed to make discoveries about different aspects of oxygen transport. Finally, ways in which oxygen might participate in the regulation of blood flow toward matching oxygen supply to oxygen demand is discussed. Overall, the transport of oxygen to the cells of the body is one of the most critical functions of the cardiovascular system and it is in the microcirculation where the final local determinants of oxygen supply, oxygen demand and their regulation are decided. PMID:23025284

  5. Macroscopic Modeling of the singlet oxygen production during PDT

    PubMed Central

    Zhu, Timothy C; Finlay, Jarod C.; Zhou, Xiaodong; Li, Jun

    2015-01-01

    Photodynamic therapy (PDT) dose, D, is defined as the absorbed dose by the photosensitizer during photodynamic therapy. It is proportional to the product of photosensitizer concentration and the light fluence. This quantity can be directly characterized during PDT and is considered to be predictive of photodynamic efficacy under ample oxygen supply. For type-II photodynamic interaction, the cell killing is caused by the reaction of cellular acceptors with singlet oxygen. The production of singlet oxygen can be expressed as ηD, where η is the singlet oxygen quantum yield and is a constant under ample oxygen supply. For most PDT, it is desirable to also take into account the effect of tissue oxygenation. We have modeled the coupled kinetics equation of the concentrations of the singlet oxygen, the photosensitizers in ground and triplet states, the oxygen, and tissue acceptors along with the diffusion equation governing the light transport in turbid medium. We have shown that it is possible to express η as a function of local oxygen concentration during PDT and this expression is a good approximation to predict the production of singlet oxygen during PDT. Theoretical estimation of the correlation between the tissue oxygen concentration and hemoglobin concentration, oxygen saturation, and blood flow is presented. PMID:25983366

  6. Identification of an Archean marine oxygen oasis

    SciTech Connect

    Riding, Dr Robert E; Fralick, Dr Philip; Liang, Liyuan

    2014-01-01

    The early Earth was essentially anoxic. A number of indicators suggest the presence of oxygenic photosynthesis 2700 3000 million years (Ma) ago, but direct evidence for molecular oxygen (O2) in seawater has remained elusive. Here we report rare earth element (REE) analyses of 2800 million year old shallowmarine limestones and deep-water iron-rich sediments at Steep Rock Lake, Canada. These show that the seawater from which extensive shallow-water limestones precipitated was oxygenated, whereas the adjacent deeper waters where iron-rich sediments formed were not. We propose that oxygen promoted limestone precipitation by oxidative removal of dissolved ferrous iron species, Fe(II), to insoluble Fe(III) oxyhydroxide, and estimate that at least 10.25 M oxygen concentration in seawater was required to accomplish this at Steep Rock. This agrees with the hypothesis that an ample supply of dissolved Fe(II) in Archean oceans would have hindered limestone formation. There is no direct evidence for the oxygen source at Steep Rock, but organic carbon isotope values and diverse stromatolites in the limestones suggest the presence of cyanobacteria. Our findings support the view that during the Archean significant oxygen levels first developed in protected nutrient-rich shallow marine habitats. They indicate that these environments were spatially restricted, transient, and promoted limestone precipitation. If Archean marine limestones in general reflect localized oxygenic removal of dissolved iron at the margins of otherwise anoxic iron-rich seas, then early oxygen oases are less elusive than has been assumed.

  7. Perioperative supply chain management.

    PubMed

    Feistritzer, N R; Keck, B R

    2000-09-01

    Faced with declining revenues and increasing operating expenses, hospitals are evaluating numerous mechanisms designed to reduce costs while simultaneously maintaining quality care. Many facilities have targeted initial cost reduction efforts in the reduction of labor expenses. Once labor expenses have been "right sized," facilities have continued to focus on service delivery improvements by the optimization of the "supply chain" process. This report presents a case study of the efforts of Vanderbilt University Medical Center in the redesign of its supply chain management process in the department of Perioperative Services. Utilizing a multidisciplinary project management structure, 3 work teams were established to complete the redesign process. To date, the project has reduced costs by $2.3 million and enhanced quality patient care by enhancing the delivery of appropriate clinical supplies during the perioperative experience.

  8. Region 8: Colorado Lamar and Steamboat Springs Adequate Letter (11/12/2002)

    EPA Pesticide Factsheets

    This letter from EPA to Colorado Department of Public Health and Environment determined Lamar and Steamboat Springs particulate matter (PM10) maintenance plan for Motor Vehicle Emissions Budgets adequate for transportation conformity purposes

  9. 75 FR 5893 - Suspension of Community Eligibility for Failure To Maintain Adequate Floodplain Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-05

    ... To Maintain Adequate Floodplain Management Regulations AGENCY: Federal Emergency Management Agency... floodplain management regulations meeting minimum requirements under the National Flood Insurance Program... they have brought their floodplain management regulations into compliance with the NFIP...

  10. Region 9: California Adequate / Inadequate Letter Attachment (5/30/2008)

    EPA Pesticide Factsheets

    This is a document that states that it has been found adequate for transportation conformitypurposes certain 8-hour ozone and PM2.5 motor vehicleemissions budgets in the 2007 South Coast StateImplementation Plan.

  11. Measurement of arterial and capillary blood oxygen tension

    PubMed Central

    Johnstone, J. H.

    1966-01-01

    An oxygen electrode system, supplied as an attachment to the Radiometer Astrup micro equipment for blood pH determination (AME I), has been investigated. Determination of blood oxygen tension using this electrode system has been compared with tension measurements using an established Bishop type oxygen electrode and satisfactory agreement was found. The storage of blood for routine estimation of oxygen tension has been investigated. Capillary blood oxygen tension has been measured and compared with that of simultaneously taken arterial blood samples. PMID:5929338

  12. Coal supply for California

    NASA Technical Reports Server (NTRS)

    Yancik, J. J.

    1978-01-01

    The potential sources and qualities of coals available for major utility and industrial consumers in California are examined and analyzed with respect to those factors that would affect the reliability of supplies. Other considerations, such as the requirements and assurances needed by the coal producers to enter into long-term contracts and dedicate large reserves of coal to these contracts are also discussed. Present and potential future mining contraints on coal mine operators are identified and analyzed with respect to their effect on availability of supply.

  13. Individual and contextual determinants of adequate maternal health care services in Kenya.

    PubMed

    Achia, Thomas N O; Mageto, Lillian E

    2015-01-01

    This study aimed to examine individual and community level factors associated with adequate use of maternal antenatal health services in Kenya. Individual and community level factors associated with adequate use of maternal health care (MHC) services were obtained from the 2008-09 Kenya Demographic and Health Survey data set. Multilevel partial-proportional odds logit models were fitted using STATA 13.0 to quantify the relations of the selected covariates to adequate MHC use, defined as a three-category ordinal variable. The sample consisted of 3,621 women who had at least one live birth in the five-year period preceding this survey. Only 18 percent of the women had adequate use of MHC services. Greater educational attainment by the woman or her partner, higher socioeconomic status, access to medical insurance coverage, and greater media exposure were the individual-level factors associated with adequate use of MHC services. Greater community ethnic diversity, higher community-level socioeconomic status, and greater community-level health facility deliveries were the contextual-level factors associated with adequate use of MHC. To improve the use of MHC services in Kenya, the government needs to design and implement programs that target underlying individual and community level factors, providing focused and sustained health education to promote the use of antenatal, delivery, and postnatal care.

  14. Mutagenicity of Oxygen Free Radicals

    NASA Astrophysics Data System (ADS)

    Moody, Carmella S.; Hassan, Hosni M.

    1982-05-01

    Paraquat 1,1'-dimethyl-4,4'-bipyridinium dichloride) was used as an intracellular generator of oxygen free radicals and was found to be highly mutagenic for Salmonella typhimurium. It caused both base-pair substitution and frameshift mutations. Paraquat was much more toxic and mutagenic in a simple nutritionally restricted medium than in a rich complex medium. The mutagenicity of paraquat was dependent upon the presence of a supply of both electrons and oxygen. Cells containing high levels of superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) were more resistant to the toxicity and the mutagenicity of paraquat than were cells containing normal levels of this enzyme. The mutagenicity of paraquat thus appears to be due to its ability to exacerbate the intracellular production of superoxide radicals.

  15. Supply-Chain Optimization Template

    NASA Technical Reports Server (NTRS)

    Quiett, William F.; Sealing, Scott L.

    2009-01-01

    The Supply-Chain Optimization Template (SCOT) is an instructional guide for identifying, evaluating, and optimizing (including re-engineering) aerospace- oriented supply chains. The SCOT was derived from the Supply Chain Council s Supply-Chain Operations Reference (SCC SCOR) Model, which is more generic and more oriented toward achieving a competitive advantage in business.

  16. Evaluation of the Draeger LAR V Pure Oxygen Scuba

    DTIC Science & Technology

    1975-10-08

    SUPPLEMENTARY NOTES 19. KEY WORDS (Continue on reverse aide If necessar’y and identify by block number) r- SCUBA -PURE OXYGEN CLOSED CIRCUIT OXYGEN A03UTRACT...apparatus des~igned and manufactured in the Federal Republic of Germany. The scuba is completely closed circuit and incorporates a demand type oxygen supply...incorporates many inherent design features which makes it easier to pre/post dive and to maintain than the Emerein closed circuit scuba Test were conducted by

  17. The effect of oxygen on denitrification during steady-state growth of Paracoccus halodenitrificans

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Betlach, M.; Kritikos, G.

    1984-01-01

    Steady-state cultures of Paracoccus halodenitrificans were grown anaerobically prior to establishing steady states at different concentrations of oxygen. In the absence of oxygen, nitrate-limited cultures produced dinitrogen, and as the oxygen supply increased, these cultures produced nitrous oxide, then nitrite. These changes reflected two phenomena: the inactivation of nitrous oxide reductase by oxygen and the diversion of electrons from nitrite to oxygen.

  18. Lightweight Regulated Power Supply

    NASA Technical Reports Server (NTRS)

    Mclyman, C. W.

    1985-01-01

    Power-supply circuit regulates output voltage by adjusting frequency of chopper circuit according to variations. Currently installed in battery charger for electric wheelchair, circuit is well suited to other uses in which light weight is important - for example, in portable computers, radios, and test instruments.

  19. Teleconnected food supply shocks

    NASA Astrophysics Data System (ADS)

    Bren d'Amour, Christopher; Wenz, Leonie; Kalkuhl, Matthias; Steckel, Jan Christoph; Creutzig, Felix

    2016-03-01

    The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks.

  20. Exploration Supply Chain Simulation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Exploration Supply Chain Simulation project was chartered by the NASA Exploration Systems Mission Directorate to develop a software tool, with proper data, to quantitatively analyze supply chains for future program planning. This tool is a discrete-event simulation that uses the basic supply chain concepts of planning, sourcing, making, delivering, and returning. This supply chain perspective is combined with other discrete or continuous simulation factors. Discrete resource events (such as launch or delivery reviews) are represented as organizational functional units. Continuous resources (such as civil service or contractor program functions) are defined as enabling functional units. Concepts of fixed and variable costs are included in the model to allow the discrete events to interact with cost calculations. The definition file is intrinsic to the model, but a blank start can be initiated at any time. The current definition file is an Orion Ares I crew launch vehicle. Parameters stretch from Kennedy Space Center across and into other program entities (Michaud Assembly Facility, Aliant Techsystems, Stennis Space Center, Johnson Space Center, etc.) though these will only gain detail as the file continues to evolve. The Orion Ares I file definition in the tool continues to evolve, and analysis from this tool is expected in 2008. This is the first application of such business-driven modeling to a NASA/government-- aerospace contractor endeavor.

  1. Supply chain management.

    PubMed

    Palevich, R F

    1999-02-01

    This article describes how Do It Best Corp. has used technology to improve its supply chain management. Among other topics it discusses the company's use of electronic data interchange, the Internet, electronic forecasting, and warehouse management systems to gain substantial savings and increase its competitiveness.

  2. Maintenance and supply options

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The object of the Maintenance and Supply Option was to develop a high level operational philosophy related to maintenance and supply operations and incorporate these concepts into the Lunar Base Study. Specific products to be generated during this task were three trade studies and a conceptual design of the Logistic Supply Module. The crew size study was performed to evaluate crew sizes from the baseline size of four to a crew size of eight and determine the preferred crew size. The second trade study was to determine the impact of extending surface stay times and recommend a preferred duration of stay time as a function of crew, consumables, and equipment support capabilities. The third trade study was an evaluation of packaging and storage methods to determine the preferred logistics approach to support the lunar base. A modified scenario was developed and served as the basis of the individual trade studies. Assumptions and guidelines were also developed from experience with Apollo programs, Space Shuttle operations, and Space Station studies. With this information, the trade studies were performed and a conceptual design for the Logistic Supply Module was developed.

  3. Baby supplies you need

    MedlinePlus

    ... Newborn care - baby supplies References Carlo WA. The newborn infant. In: Kliegman RM, Stanton BF, St Geme JW, ... A.M. Editorial team. Related MedlinePlus Health Topics Infant and Newborn Care Browse the Encyclopedia A.D.A.M., ...

  4. Supply chain quality.

    PubMed

    Feary, Simon

    2009-01-01

    As the development of complex manufacturing models and virtual companies become more prevalent in today's growing global markets, it is increasingly important to support the relationships between manufacturer and supplier. Utilising these relationships will ensure that supply chains operate more effectively and reduce costs, risks and time-to-market time frames, whilst maintaining product quality.

  5. Home Oxygen Therapy

    MedlinePlus

    ... oxygen is rarely delivered in the older large, steel gas cylinders any longer since frequent and costly ... just like the compressed oxygen in the older steel cylinders. An important advantage of liquid oxygen is ...

  6. Managing Water supply in Developing Countries

    NASA Astrophysics Data System (ADS)

    Rogers, P. P.

    2001-05-01

    If the estimates are correct that, in the large urban areas of the developing world 30 percent of the population lack access to safe water supply and 50 percent lack access to adequate sanitation, then we are currently faced with 510 million urban residents without access to domestic water and 850 million without access to sanitation. Looking to the year 2020, we will face an additional 1,900 million in need of water and sanitation services. The provision of water services to these billions of people over the next two decades is one of the greatest challenges facing the nations of the world. In addition to future supplies, major problems exist with the management of existing systems where water losses can account for a significant fraction of the water supplied. The entire governance of the water sector and the management of particular systems raise serious questions about the application of the best technologies and the appropriate economic incentive systems. The paper outlines a few feasible technical and economic solutions.

  7. The feasibility of producing adequate feedstock for year–round cellulosic ethanol production in an intensive agricultural fuelshed

    USGS Publications Warehouse

    Uden, Daniel R.; Mitchell, Rob B.; Allen, Craig R.; Guan, Qingfeng; McCoy, Tim D.

    2013-01-01

    To date, cellulosic ethanol production has not been commercialized in the United States. However, government mandates aimed at increasing second-generation biofuel production could spur exploratory development in the cellulosic ethanol industry. We conducted an in-depth analysis of the fuelshed surrounding a starch-based ethanol plant near York, Nebraska that has the potential for cellulosic ethanol production. To assess the feasibility of supplying adequate biomass for year-round cellulosic ethanol production from residual maize (Zea mays) stover and bioenergy switchgrass (Panicum virgatum) within a 40-km road network service area of the existing ethanol plant, we identified ∼14,000 ha of marginally productive cropland within the service area suitable for conversion from annual rowcrops to switchgrass and ∼132,000 ha of maize-enrolled cropland from which maize stover could be collected. Annual maize stover and switchgrass biomass supplies within the 40-km service area could range between 429,000 and 752,000 metric tons (mT). Approximately 140–250 million liters (l) of cellulosic ethanol could be produced, rivaling the current 208 million l annual starch-based ethanol production capacity of the plant. We conclude that sufficient quantities of biomass could be produced from maize stover and switchgrass near the plant to support year-round cellulosic ethanol production at current feedstock yields, sustainable removal rates and bioconversion efficiencies. Modifying existing starch-based ethanol plants in intensive agricultural fuelsheds could increase ethanol output, return marginally productive cropland to perennial vegetation, and remove maize stover from productive cropland to meet feedstock demand.

  8. Oxygen Candle Background for Subs and Space

    NASA Technical Reports Server (NTRS)

    Graf, John

    2017-01-01

    "At any time and without warning, a submarine may have to remain submerged for several days on account of the presence of the enemy, or rough weather, or serious accident to the machinery. Fortunately such occurrences are rare; but every commanding officer must be prepared to meet such an emergency that will afford his men the greatest possible chance of survival." Reference (1) This quotation is taken from a review of submarine air purification technology published by the Bureau of Medicine and Surgery in 1919. At that time, the U.S. Navy had just begun to experiment with possible air purification devices and supplies of oxygen that might permit submarines to remain submerged longer that the untreated closed atmosphere would allow. Submariners were exposed to elevated levels of carbon dioxide and reduced levels of oxygen that would be considered completely unacceptable by current standards. It was a different world, but humans are still humans, and the requirements for safe and effective functioning in a self-contained environment are really unchanged. The maximum submergence time for submarines as published in that work was approximately 48 hours, reference (1) In early submarines, the preferred supply of oxygen was 1800 psig compressed gas bled into the boat as needed, references (1,2). The need for added oxygen was occasionally "measured" by the physiological impact on the crew rather than a reliable instrument, reference (1). The design of submarine oxygen supply was limited to approximately 25 day submerged operation, reference (2). It was not until 1958 that U.S. submarines were able to carry out dives beyond that period and necessitated new sources of oxygen, reference (2). A curious second source of oxygen at the time was compressed air vessels that were bled into the boat while "vitiated" air (air with reduced oxygen and elevated carbon dioxide) from the opposite end of the boat was compressed into waiting empty vessels, reference (1). The periodic use of

  9. Development of water quality standards criteria. [for consumables (spacecrew supplies)

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Qualitative and semiquantitative analyses were made of volatile organic compounds in water supplies collected at various stages of processing in the space station prototype vacuum compression distillation unit to evaluate the process and the product water. Additional evaluation was made of specific ingredients required to adequately enhance the taste of the reclaimed water. A concept for the in-flight addition of these ingredients was developed. Revisions to previously recommended potable water criteria and specifications are included.

  10. High voltage power supply

    NASA Technical Reports Server (NTRS)

    Ruitberg, A. P.; Young, K. M. (Inventor)

    1985-01-01

    A high voltage power supply is formed by three discrete circuits energized by a battery to provide a plurality of concurrent output signals floating at a high output voltage on the order of several tens of kilovolts. In the first two circuits, the regulator stages are pulse width modulated and include adjustable ressistances for varying the duty cycles of pulse trains provided to corresponding oscillator stages while the third regulator stage includes an adjustable resistance for varying the amplitude of a steady signal provided to a third oscillator stage. In the first circuit, the oscillator, formed by a constant current drive network and a tuned resonant network included a step up transformer, is coupled to a second step up transformer which, in turn, supplies an amplified sinusoidal signal to a parallel pair of complementary poled rectifying, voltage multiplier stages to generate the high output voltage.

  11. Discontinuous Mode Power Supply

    NASA Technical Reports Server (NTRS)

    Lagadinos, John; Poulos, Ethel

    2012-01-01

    A document discusses the changes made to a standard push-pull inverter circuit to avoid saturation effects in the main inverter power supply. Typically, in a standard push-pull arrangement, the unsymmetrical primary excitation causes variations in the volt second integral of each half of the excitation cycle that could lead to the establishment of DC flux density in the magnetic core, which could eventually cause saturation of the main inverter transformer. The relocation of the filter reactor normally placed across the output of the power supply solves this problem. The filter reactor was placed in series with the primary circuit of the main inverter transformer, and is presented as impedance against the sudden changes on the input current. The reactor averaged the input current in the primary circuit, avoiding saturation of the main inverter transformer. Since the implementation of the described change, the above problem has not reoccurred, and failures in the main power transistors have been avoided.

  12. Importance of adequate exercise in the detection of coronary heart disease by radionuclide ventriculography

    SciTech Connect

    Brady, T.J.; Thrall, J.H.; Lo, K.; Pitt, B.

    1980-12-01

    Rest and exercise radionuclide ventriculograms were obtained on 77 symptomatic patients without prior documented coronary artery disease (CAD). Coronary artery disease was present by angiograms in 48. Radionuclide ventriculography (RNV) was abnormal in 41 patients (overall sensitivity 85%). In 29 patients with normal coronary arteries, RNV was normal in 24 (specificity 83%). To determine if the exercise level affects sensitivity, the studies were graded for adequacy of exercise. It was considered adequate if patients developed (a) chest pain, or (b) ST segment depression of at least 1 mm, or (c) if they achieved a pressure rate product greater than 250. Among the 48 patients with coronary artery disease, 35 achieved adequate exercise. Thirty-three had an abnormal RNV (sensitivity 94%). In 13 patients who failed to achieve adequate exercise, RNV was abnormal in eight (sensitivity of only 62%). Some patients with coronary artery disease may have a normal ventricular response at inadequate levels of stress.

  13. [Prevention of ocular complications of herpes zoster ophthalmicus by adequate treatment with acyclovir].

    PubMed

    Borruat, F X; Buechi, E R; Piguet, B; Fitting, P; Zografos, L; Herbort, C P

    1991-05-01

    We compared the frequency of severe ocular complications secondary to Herpes Zoster Ophthalmicus (HZO) in 232 patients. They were divided into three groups: 1) patients without treatment (n = 164); 2) patients treated adequately (n = 48) with acyclovir (ACV; 5 x 800 mg/d orally and ophthalmic ointment 5 x /d for a minimum of 7 days, given within three days after skin eruption); and, 3) patients treated inadequately (n = 20) with ACV (only topical treatment, insufficient doses, interrupted treatment, delayed treatment). Patients with no treatment or with inadequate treatments showed the same frequency of severe ocular complications (21% (34/164) and 25% (5/20), respectively). In contrast, when adequate treatment of ACV was given complications occurred in only 4% (2/48) of cases. This study emphasizes the need for prompt (within three days after skin eruption) and adequate (5 x 800 mg/d for at least 7 days) treatment of ACV to prevent the severe complications of HZO.

  14. Supply Chain Interoperability Measurement

    DTIC Science & Technology

    2015-06-19

    Supply Chain Interoperability Measurement DISSERTATION June 2015 Christos E. Chalyvidis, Major, Hellenic Air ...Force AFIT-ENS-DS-15-J-001 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force...are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United

  15. Streamlining the supply chain.

    PubMed

    Neumann, Lydon

    2003-07-01

    Effective management of the supply chain requires attention to: Product management--formulary development and maintenance, compliance, clinical involvement, standardization, and demand-matching. Sourcing and contracting--vendor consolidation, GPO portfolio management, price leveling, content management, and direct contracting Purchasing and payment-cycle--automatic placement, web enablement, centralization, evaluated receipts settlement, and invoice matching Inventory and distribution management--"unofficial" and "official" locations, vendor-managed inventory, automatic replenishment, and freight management.

  16. Broadband inversion of 1J(CC) responses in 1,n-ADEQUATE spectra.

    PubMed

    Reibarkh, Mikhail; Williamson, R Thomas; Martin, Gary E; Bermel, Wolfgang

    2013-11-01

    Establishing the carbon skeleton of a molecule greatly facilitates the process of structure elucidation, both manual and computer-assisted. Recent advances in the family of ADEQUATE experiments demonstrated their potential in this regard. 1,1-ADEQUATE, which provides direct (13)C-(13)C correlation via (1)J(CC), and 1,n-ADEQUATE, which typically yields (3)J(CC) and (1)J(CC) correlations, are more sensitive and more widely applicable experiments than INADEQUATE and PANACEA. A recently reported modified pulse sequence that semi-selectively inverts (1)J(CC) correlations in 1,n-ADEQUATE spectra provided a significant improvement, allowing (1)J(CC) and (n)J(CC) correlations to be discerned in the same spectrum. However, the reported experiment requires a careful matching of the amplitude transfer function with (1)J(CC) coupling constants in order to achieve the inversion, and even then some (1)J(CC) correlations could still have positive intensity due to the oscillatory nature of the transfer function. Both shortcomings limit the practicality of the method. We now report a new, dual-optimized inverted (1)J(CC) 1,n-ADEQUATE experiment, which provides more uniform inversion of (1)J(CC) correlations across the range of 29-82 Hz. Unlike the original method, the dual optimization experiment does not require fine-tuning for the molecule's (1)J(CC) coupling constant values. Even more usefully, the dual-optimized version provides up to two-fold improvement in signal-to-noise for some long-range correlations. Using modern, cryogenically-cooled probes, the experiment can be successfully applied to samples of ~1 mg under favorable circumstances. The improvements afforded by dual optimization inverted (1)J(CC) 1,n-ADEQUATE experiment make it a useful and practical tool for NMR structure elucidation and should facilitate the implementation and utilization of the experiment.

  17. Solid electrolyte oxygen regeneration system

    NASA Technical Reports Server (NTRS)

    Shumar, J. W.; See, G. G.; Schubert, F. H.; Powell, J. D.

    1976-01-01

    A program to design, develop, fabricate and assemble a one-man, self-contained, solid electrolyte oxygen regeneration system (SX-1) incorporating solid electrolyte electrolyzer drums was completed. The SX-1 is a preprototype engineering model designed to produce 0.952 kg (2.1 lb)/day of breathable oxygen (O2) from the electrolysis of metabolic carbon dioxide (CO2) and water vapor. The CO2 supply rate was established based on the metabolic CO2 generation rate for one man of 0.998 kg (2.2 lb)/day. The water supply rate (0.254 kg (0.56 lb)/day) was designed to be sufficient to make up the difference between the 0.952 kg (2.1 lb)/day O2 generation specification and the O2 available through CO2 electrolysis, 0.726 kg (1.6 lb)/day. The SX-1 was successfully designed, fabricated and assembled. Design verification tests (DVT) or the CO Disproportionators, H2 separators, control instrumentation, monitor instrumentation, water feed mechanism were successfully completed. The erratic occurrence of electrolyzer drum leakage prevented the completion of the CO2 electrolyzer module and water electrolyzer module DVT's and also prevented the performance of SX-1 integrated testing. Further development work is required to improve the solid electrolyte cell high temperature seals.

  18. Oxygen deficit determinations for a major river in eastern Hong Kong, China.

    PubMed

    Chen, G H; Leong, I M; Liu, J; Huang, J C; Lo, I M; Yen, B C

    2000-07-01

    Determination of oxygen deficit in the Hong Kong Shing-Mun River was based on the oxygen uptake by water, algal respiration and river sediment and the oxygen supplied to the river by surface reaeration and algal photosynthesis. A systematic study was conducted to examine the effect of water temperature, flow velocity and water depth on both the oxygen demands and the oxygen supplies. The oxygen budget of a water column in a selected section of the river was modeled. The results of the oxygen budget analysis showed that when water temperature was around 10 degrees C (the lowest temperature in the river), no deficit was observed. When water temperature was 10 degrees C to 20 degrees C, a small oxygen deficit appeared, especially in the deeper water. At the highest water temperature (30 degrees C), the oxygen deficit was maximal, -6.84 g O2/m2/day, in the night-time during the Spring tide period.

  19. Self-reported segregation experience throughout the life course and its association with adequate health literacy.

    PubMed

    Goodman, Melody S; Gaskin, Darrell J; Si, Xuemei; Stafford, Jewel D; Lachance, Christina; Kaphingst, Kimberly A

    2012-09-01

    Residential segregation has been shown to be associated with health outcomes and health care utilization. We examined the association between racial composition of five physical environments throughout the life course and adequate health literacy among 836 community health center patients in Suffolk County, NY. Respondents who attended a mostly White junior high school or currently lived in a mostly White neighborhood were more likely to have adequate health literacy compared to those educated or living in predominantly minority or diverse environments. This association was independent of the respondent's race, ethnicity, age, education, and country of birth.

  20. Self-reported segregation experience throughout the life course and its association with adequate health literacy

    PubMed Central

    Gaskin, Darrell J.; Si, Xuemei; Stafford, Jewel D.; Lachance, Christina; Kaphingst, Kimberly A.

    2012-01-01

    Residential segregation has been shown to be associated with health outcomes and health care utilization. We examined the association between racial composition of five physical environments throughout the life course and adequate health literacy among 836 community health center patients in Suffolk County, NY. Respondents who attended a mostly White junior high school or currently lived in a mostly White neighborhood were more likely to have adequate health literacy compared to those educated or living in predominantly minority or diverse environments. This association was independent of the respondent’s race, ethnicity, age, education, and country of birth. PMID:22658579

  1. Medical Care for Echelons Above Divisions - Is Medical Force 2000 Adequate to Need?

    DTIC Science & Technology

    1992-04-08

    exercised during Operation Just Cause in Panama proved to be such a workable concept that it was also exercised during the Gulf conflict. Similar...Medical Battalion becomes a multifunctional organization encompassing preventive medicine, optometry , mental health, and medical supply in the medical...Provides Preventive Medicine, Combat Stress, Optometry , and Emergency Surgery to the Division. Provides Class VIII supply/resupply for Division from

  2. Artificial oxygen transport protein

    DOEpatents

    Dutton, P. Leslie

    2014-09-30

    This invention provides heme-containing peptides capable of binding molecular oxygen at room temperature. These compounds may be useful in the absorption of molecular oxygen from molecular oxygen-containing atmospheres. Also included in the invention are methods for treating an oxygen transport deficiency in a mammal.

  3. Effect of 6-day hypokinesia on oxygen metabolism indices in elderly and senile subjects

    NASA Technical Reports Server (NTRS)

    Ivanov, L. A.; Orlov, P. A.

    1978-01-01

    After a strict 6 day confinement to bed of elderly and senile subjects the oxygen supply of the subcutaneous cellular tissue was impaired, and the intensity of its tissue respiration was somewhat reduced. The vacat-oxygen of the blood and urine, the coefficient of incomplete oxidation, and the oxygen deficiency in the organism were increased.

  4. Drivers of summer oxygen depletion in the central North Sea

    NASA Astrophysics Data System (ADS)

    Queste, Bastien Y.; Fernand, Liam; Jickells, Timothy D.; Heywood, Karen J.; Hind, Andrew J.

    2016-02-01

    In stratified shelf seas, oxygen depletion beneath the thermocline is a result of a greater rate of biological oxygen demand than the rate of supply of oxygenated water. Suitably equipped gliders are uniquely placed to observe both the supply through the thermocline and the consumption of oxygen in the bottom layers. A Seaglider was deployed in the shallow (≍ 100 m) stratified North Sea in a region of known low oxygen during August 2011 to investigate the processes regulating supply and consumption of dissolved oxygen below the pycnocline. The first deployment of such a device in this area, it provided extremely high-resolution observations, 316 profiles (every 16 min, vertical resolution of 1 m) of conductivity, temperature, and depth (CTD), dissolved oxygen concentrations, backscatter, and fluorescence during a 3-day deployment.The high temporal resolution observations revealed occasional small-scale events (< 200 m or 6 h) that supply oxygenated water to the bottom layer at a rate of 2 ± 1 µmol dm-3 day-1. Benthic and pelagic oxygen sinks, quantified through glider observations and past studies, indicate more gradual background consumption rates of 2.5 ± 1 µmol dm-3 day-1. This budget revealed that the balance of oxygen supply and demand is in agreement with previous studies of the North Sea. However, the glider data show a net oxygen consumption rate of 2.8 ± 0.3 µmol dm-3 day-1, indicating a localized or short-lived (< 200 m or 6 h) increase in oxygen consumption rates. This high rate of oxygen consumption is indicative of an unidentified oxygen sink. We propose that this elevated oxygen consumption is linked to localized depocentres and rapid remineralization of resuspended organic matter.The glider proved to be an excellent tool for monitoring shelf sea processes despite challenges to glider flight posed by high tidal velocities, shallow bathymetry, and very strong density gradients. The direct observation of these processes allows more up to date

  5. Hyperbaric oxygen therapy and preconditioning for ischemic and hemorrhagic stroke

    PubMed Central

    Hu, Sheng-li; Feng, Hua; Xi, Guo-hua

    2016-01-01

    To date, the therapeutic methods for ischemic and hemorrhagic stroke are still limited. The lack of oxygen supply is critical for brain injury following stroke. Hyperbaric oxygen (HBO), an approach through a process in which patients breathe in 100% pure oxygen at over 101 kPa, has been shown to facilitate oxygen delivery and increase oxygen supply. Hence, HBO possesses the potentials to produce beneficial effects on stroke. Actually, accumulated basic and clinical evidences have demonstrated that HBO therapy and preconditioning could induce neuroprotective functions via different mechanisms. Nevertheless, the lack of clinical translational study limits the application of HBO. More translational studies and clinical trials are needed in the future to develop effective HBO protocols. PMID:28217297

  6. Oxygen sensing and signaling.

    PubMed

    van Dongen, Joost T; Licausi, Francesco

    2015-01-01

    Oxygen is an indispensable substrate for many biochemical reactions in plants, including energy metabolism (respiration). Despite its importance, plants lack an active transport mechanism to distribute oxygen to all cells. Therefore, steep oxygen gradients occur within most plant tissues, which can be exacerbated by environmental perturbations that further reduce oxygen availability. Plants possess various responses to cope with spatial and temporal variations in oxygen availability, many of which involve metabolic adaptations to deal with energy crises induced by low oxygen. Responses are induced gradually when oxygen concentrations decrease and are rapidly reversed upon reoxygenation. A direct effect of the oxygen level can be observed in the stability, and thus activity, of various transcription factors that control the expression of hypoxia-induced genes. Additional signaling pathways are activated by the impact of oxygen deficiency on mitochondrial and chloroplast functioning. Here, we describe the molecular components of the oxygen-sensing pathway.

  7. 10 CFR 503.31 - Lack of alternate fuel supply for the first 10 years of useful life.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... made to obtain an adequate and reliable supply of an alternate fuel for use as a primary energy source... 10 Energy 4 2013-01-01 2013-01-01 false Lack of alternate fuel supply for the first 10 years of useful life. 503.31 Section 503.31 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW...

  8. 10 CFR 503.31 - Lack of alternate fuel supply for the first 10 years of useful life.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... made to obtain an adequate and reliable supply of an alternate fuel for use as a primary energy source... 10 Energy 4 2012-01-01 2012-01-01 false Lack of alternate fuel supply for the first 10 years of useful life. 503.31 Section 503.31 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW...

  9. 10 CFR 503.31 - Lack of alternate fuel supply for the first 10 years of useful life.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... made to obtain an adequate and reliable supply of an alternate fuel for use as a primary energy source... 10 Energy 4 2014-01-01 2014-01-01 false Lack of alternate fuel supply for the first 10 years of useful life. 503.31 Section 503.31 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW...

  10. 10 CFR 503.31 - Lack of alternate fuel supply for the first 10 years of useful life.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... made to obtain an adequate and reliable supply of an alternate fuel for use as a primary energy source... 10 Energy 4 2011-01-01 2011-01-01 false Lack of alternate fuel supply for the first 10 years of useful life. 503.31 Section 503.31 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW...

  11. 10 CFR 503.31 - Lack of alternate fuel supply for the first 10 years of useful life.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... made to obtain an adequate and reliable supply of an alternate fuel for use as a primary energy source... 10 Energy 4 2010-01-01 2010-01-01 false Lack of alternate fuel supply for the first 10 years of useful life. 503.31 Section 503.31 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW...

  12. Oxygen Sensing and Homeostasis

    PubMed Central

    Semenza, Gregg L.

    2015-01-01

    The discovery of carotid bodies as sensory receptors for detecting arterial blood oxygen levels, and the identification and elucidation of the roles of hypoxia-inducible factors (HIFs) in oxygen homeostasis have propelled the field of oxygen biology. This review highlights the gas-messenger signaling mechanisms associated with oxygen sensing, as well as transcriptional and non-transcriptional mechanisms underlying the maintenance of oxygen homeostasis by HIFs and their relevance to physiology and pathology. PMID:26328879

  13. Visible light optical coherence tomography measures retinal oxygen metabolic response to systemic oxygenation

    PubMed Central

    Yi, Ji; Liu, Wenzhong; Chen, Siyu; Backman, Vadim; Sheibani, Nader; Sorenson, Christine M.; Fawzi, Amani A.; Linsenmeier, Robert A.; Zhang, Hao F.

    2015-01-01

    The lack of capability to quantify oxygen metabolism noninvasively impedes both fundamental investigation and clinical diagnosis of a wide spectrum of diseases including all the major blinding diseases such as age-related macular degeneration, diabetic retinopathy, and glaucoma. Using visible light optical coherence tomography (vis-OCT), we demonstrated accurate and robust measurement of retinal oxygen metabolic rate (rMRO2) noninvasively in rat eyes. We continuously monitored the regulatory response of oxygen consumption to a progressive hypoxic challenge. We found that both oxygen delivery, and rMRO2 increased from the highly regulated retinal circulation (RC) under hypoxia, by 0.28 ± 0.08 μL min−1 (p < 0.001), and 0.20 ± 0.04 μL min−1 (p < 0.001) per 100 mmHg systemic pO2 reduction, respectively. The increased oxygen extraction compensated for the deficient oxygen supply from the poorly regulated choroidal circulation. Results from an oxygen diffusion model based on previous oxygen electrode measurements corroborated our in vivo observations. We believe that vis-OCT has the potential to reveal the fundamental role of oxygen metabolism in various retinal diseases. PMID:26658555

  14. 75 FR 69648 - Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... ENERGY Safety Analysis Requirements for Defining Adequate Protection for the Public and the Workers... designed to hold firmly in place. 10 CFR Part 830 imposes a requirement that a documented safety analysis... provide guidance on meeting the requirements imposed by DOE Order 5480.23, Nuclear Safety Analysis...

  15. 42 CFR 413.24 - Adequate cost data and cost finding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... Adequate data capable of being audited is consistent with good business concepts and effective and efficient management of any organization, whether it is operated for profit or on a nonprofit basis. It is a... contract for services (for example, a management contract), directly assigning the costs to the...

  16. Prenatal zinc supplementation of zinc-adequate rats adversely affects immunity in offspring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We previously showed that zinc (Zn) supplementation of Zn-adequate dams induced immunosuppressive effects that persist in the offspring after weaning. We investigated whether the immunosuppressive effects were due to in utero exposure and/or mediated via milk using a cross-fostering design. Pregnant...

  17. Towards Defining Adequate Lithium Trials for Individuals with Mental Retardation and Mental Illness.

    ERIC Educational Resources Information Center

    Pary, Robert J.

    1991-01-01

    Use of lithium with mentally retarded individuals with psychiatric conditions and/or behavior disturbances is discussed. The paper describes components of an adequate clinical trial and reviews case studies and double-blind cases. The paper concludes that aggression is the best indicator for lithium use, and reviews treatment parameters and…

  18. ADEQUATE SHELTERS AND QUICK REACTIONS TO WARNING: A KEY TO CIVIL DEFENSE.

    PubMed

    LYNCH, F X

    1963-11-08

    Case histories collected by investigators in Japan during 1945 illustrate both the effectiveness of shelters and the dangers inherent in apathy of the population, which suffered needless casualties by ignoring air raid warnintgs. Adequate shelters and immediate response to warnings are essential to survival in nuclear attack.

  19. Perceptions of Teachers in Their First Year of School Restructuring: Failure to Make Adequate Yearly Progress

    ERIC Educational Resources Information Center

    Moser, Sharon

    2010-01-01

    The 2007-2008 school year marked the first year Florida's Title I schools that did not made Adequate Yearly Progress (AYP) for five consecutive years entered into restructuring as mandated by the "No Child Left Behind Act" of 2001. My study examines the perceptions of teacher entering into their first year of school restructuring due to…

  20. 45 CFR 1182.15 - Institute responsibility for maintaining adequate technical, physical, and security safeguards to...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... record systems. These security safeguards shall apply to all systems in which identifiable personal data... data and automated systems shall be adequately trained in the security and privacy of personal data. (4... technical, physical, and security safeguards to prevent unauthorized disclosure or destruction of manual...

  1. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Adequate financial records, statistical data, and... financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination of costs payable by...

  2. Effect of tranquilizers on animal resistance to the adequate stimuli of the vestibular apparatus

    NASA Technical Reports Server (NTRS)

    Maksimovich, Y. B.; Khinchikashvili, N. V.

    1980-01-01

    The effect of tranquilizers on vestibulospinal reflexes and motor activity was studied in 900 centrifuged albino mice. Actometric studies have shown that the tranquilizers have a group capacity for increasing animal resistance to the action of adequate stimuli to the vestibular apparatus.

  3. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Attending...

  4. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Attending...

  5. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Attending...

  6. 9 CFR 2.40 - Attending veterinarian and adequate veterinary care (dealers and exhibitors).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Attending veterinarian and adequate veterinary care (dealers and exhibitors). 2.40 Section 2.40 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Attending...

  7. The Relationship between Parental Involvement and Adequate Yearly Progress among Urban, Suburban, and Rural Schools

    ERIC Educational Resources Information Center

    Ma, Xin; Shen, Jianping; Krenn, Huilan Y.

    2014-01-01

    Using national data from the 2007-08 School and Staffing Survey, we compared the relationships between parental involvement and school outcomes related to adequate yearly progress (AYP) in urban, suburban, and rural schools. Parent-initiated parental involvement demonstrated significantly positive relationships with both making AYP and staying off…

  8. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall...

  9. 9 CFR 2.33 - Attending veterinarian and adequate veterinary care.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... veterinary care. 2.33 Section 2.33 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Research Facilities § 2.33 Attending veterinarian and adequate veterinary care. (a) Each research facility shall have an attending veterinarian who shall...

  10. Identifying the Factors Impacting the Adequately Yearly Progress Performance in the United States

    ERIC Educational Resources Information Center

    Hsieh, Ju-Shan

    2013-01-01

    The NCLB (No Child Left Behind Act) specifies that states must develop AYP (adequate yearly progress) statewide measurable objectives for improved achievement by all students, including economically disadvantaged students, students from minority races, students with disabilities, and students with limited English proficiency. By the 2013-2014…

  11. 42 CFR 438.207 - Assurances of adequate capacity and services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Assurances of adequate capacity and services. 438.207 Section 438.207 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS MANAGED CARE Quality Assessment and...

  12. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Who determines when there is adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park...

  13. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Who determines when there is adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park...

  14. 76 FR 51041 - Hemoglobin Standards and Maintaining Adequate Iron Stores in Blood Donors; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Hemoglobin Standards and Maintaining Adequate Iron Stores in... workshop. The Food and Drug Administration (FDA) is announcing a public workshop entitled: ``Hemoglobin... discuss blood donor hemoglobin and hematocrit qualification standards in the United States, its impact...

  15. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  16. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  17. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  18. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  19. 21 CFR 514.117 - Adequate and well-controlled studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... adequate and well-controlled studies of a new animal drug is to distinguish the effect of the new animal... with one or more controls to provide a quantitative evaluation of drug effects. The protocol and the... for special circumstances. Examples include studies in which the effect of the new animal drug is...

  20. 30 CFR 227.801 - What if a State does not adequately perform a delegated function?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... delegated function? 227.801 Section 227.801 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT DELEGATION TO STATES Performance Review § 227.801 What if a State does not adequately perform a delegated function? If your performance of the delegated function does...

  1. Science Education as a Contributor to Adequate Yearly Progress and Accountability Programs

    ERIC Educational Resources Information Center

    Judson, Eugene

    2010-01-01

    The No Child Left Behind (NCLB) Act requires states to measure the adequate yearly progress (AYP) of each public school and local educational agency (LEA) and to hold schools and LEAs accountable for failing to make AYP. Although it is required that science be assessed in at least three grades, the achievement results from science examinations are…

  2. 42 CFR 417.568 - Adequate financial records, statistical data, and cost finding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Adequate financial records, statistical data, and... financial records, statistical data, and cost finding. (a) Maintenance of records. (1) An HMO or CMP must maintain sufficient financial records and statistical data for proper determination of costs payable by...

  3. Understanding the pelvic pain mechanism is key to find an adequate therapeutic approach.

    PubMed

    Van Kerrebroeck, Philip

    2016-06-25

    Pain is a natural mechanism to actual or potential tissue damage and involves both a sensory and an emotional experience. In chronic pelvic pain, localisation of pain can be widespread and can cause considerable distress. A multidisciplinary approach is needed in order to fully understand the pelvic pain mechanism and to identify an adequate therapeutic approach.

  4. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Who determines when there is adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park...

  5. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Who determines when there is adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park...

  6. 36 CFR 13.960 - Who determines when there is adequate snow cover?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Who determines when there is adequate snow cover? 13.960 Section 13.960 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park...

  7. Human milk feeding supports adequate growth in infants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite current nutritional strategies, premature infants remain at high risk for extrauterine growth restriction. The use of an exclusive human milk-based diet is associated with decreased incidence of necrotizing enterocolitis (NEC), but concerns exist about infants achieving adequate growth. The ...

  8. Adequate Yearly Progress for Students with Emotional and Behavioral Disorders through Research-Based Practices

    ERIC Educational Resources Information Center

    Vannest, Kimberly J.; Temple-Harvey, Kimberly K.; Mason, Benjamin A.

    2009-01-01

    Because schools are held accountable for the academic performance of all students, it is important to focus on academics and the need for effective teaching practices. Adequate yearly progress, a method of accountability that is part of the No Child Left Behind Act (2001), profoundly affects the education of students who have emotional and…

  9. How Much and What Kind? Identifying an Adequate Technology Infrastructure for Early Childhood Education. Policy Brief

    ERIC Educational Resources Information Center

    Daugherty, Lindsay; Dossani, Rafiq; Johnson, Erin-Elizabeth; Wright, Cameron

    2014-01-01

    To realize the potential benefits of technology use in early childhood education (ECE), and to ensure that technology can help to address the digital divide, providers, families of young children, and young children themselves must have access to an adequate technology infrastructure. The goals for technology use in ECE that a technology…

  10. Balancing the Risks and Benefits of Oxygen Therapy in Critically III Adults

    PubMed Central

    Mutlu, Gökhan M.

    2013-01-01

    Oxygen therapy is an integral part of the treatment of critically ill patients. Maintenance of adequate oxygen delivery to vital organs often requires the administration of supplemental oxygen, sometimes at high concentrations. Although oxygen therapy is lifesaving, it may be associated with deleterious effects when administered for prolonged periods at high concentrations. Here, we review the recent advances in our understanding of the molecular responses to hypoxia and high levels of oxygen and review the current guidelines for oxygen therapy in critically ill patients. PMID:23546490

  11. Should we be giving high concentration oxygen to all patients treated in an ambulance?

    PubMed

    Lavery, G G; Corris, P A

    2012-03-01

    Oxygen is one of the most widely used drugs. It is important to recognise that oxygen administration carries risks as well as benefits. While adequate oxygen saturation of arterial blood is an important factor in tissue oxygen delivery, oxygen administration to patients with chronic obstructive pulmonary disease can lead to decompensated type II respiratory failure. In this debate, Dr Lavery makes the case that high concentration oxygen should be given to all patients treated in an ambulance, while Professor Corris argues against this position.

  12. Power-Supply-Conditioning Circuit

    NASA Technical Reports Server (NTRS)

    Primas, L. E.; Loveland, R. C.

    1989-01-01

    Fluctuations of voltage suppressed in power supplies for precise radio-frequency circuits. Circuit suppresses both periodic and random deviations of dc supply voltage from desired steady level. Highly-stable feedback voltage regulator, conditioner intended in conjunction with conventional power-supply circuit to provide constant voltage to atomic frequency standard or other precise oscillator. Without conditioners, outputs of most commercial power supplies contain fluctuations causing unacceptably-large phase and amplitude modulation of precise oscillators.

  13. 2002 Industry Studies: Strategic Supply

    DTIC Science & Technology

    2002-01-01

    Strategic Supply is a unique industry study that focused not on a single industry, but rather on a process common to many industries known as Supply ... Chain Management (SCM). We found that the successful, global and innovative companies of today leverage their supply chains to achieve competitive and

  14. Oxygen tension level and human viral infections

    SciTech Connect

    Morinet, Frédéric; Casetti, Luana; François, Jean-Hugues; Capron, Claude; Pillet, Sylvie

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  15. Vitreal Oxygenation in Retinal Ischemia Reperfusion

    PubMed Central

    Abdallah, Walid; Ameri, Hossein; Barron, Ernesto; Chader, Gerald J.; Greenbaum, Elias; Hinton, David R.

    2011-01-01

    Purpose. To study the feasibility of anterior vitreal oxygenation for the treatment of acute retinal ischemia. Methods. Twenty rabbits were randomized into an oxygenation group, a sham treatment group, and a no treatment group. Baseline electroretinography (ERG) and preretinal oxygen (Po2) measurements were obtained 3 to 5 days before surgery. Intraocular pressure was raised to 100 mm Hg for 90 minutes and then normalized. The oxygenation group underwent vitreal oxygenation for 30 minutes using intravitreal electrodes. The sham treatment group received inactive electrodes for 30 minutes while there was no intervention for the no treatment group. Preretinal Po2 in the posterior vitreous was measured 30 minutes after intervention or 30 minutes after reperfusion (no treatment group) and on postoperative days (d) 3, 6, 9, and 12. On d14, rabbits underwent ERG and were euthanatized. Results. Mean final (d12) Po2 was 10.64 ± 0.77 mm Hg for the oxygenation group, 2.14 ± 0.61 mm Hg for the sham group, and 1.98 ± 0.63 mm Hg for the no treatment group. On ERG, scotopic b-wave amplitude was significantly preserved in the oxygenation group compared with the other two groups. Superoxide dismutase assay showed higher activity in the operated eyes than in the nonoperated control eyes in the sham treatment group and no treatment group only. Histopathology showed preservation of retinal architecture and choroidal vasculature in the oxygenation group, whereas the sham-treated and nontreated groups showed retinal thinning and choroidal atrophy. Conclusions. In severe total ocular ischemia, anterior vitreal oxygenation supplies enough oxygen to penetrate the retinal thickness, resulting in rescue of the RPE/choriocapillaris that continues to perfuse, hence sparing the retinal tissue from damage. PMID:21051734

  16. The flux of oxygen within tissues.

    PubMed

    McCabe, Michael G P; Maguire, David J; Bourgain, Renaat

    2003-01-01

    Diffusive flux of oxygen through tissues which are essentially connective and have few cells, display reduced diffusion coefficients when compared to that through an equivalent lamina of water. In general even significant reductions can be explained in terms of the exclusions imposed on small molecular weight diffusates by the large hydrodynamic domains of the connective tissue components. An alternative way of explaining this large exclusion is to point to the very large microscopic viscosities which large interacting polymers impose upon the solvent (water). By contrast, the diffusive flux of oxygen through tissues composed of contiguously packed and actively respiring cells, shows an increased diffusive flux for oxygen when compared to that through an equivalent water lamina. This increase can be explained in terms of the substantial solubility of oxygen within the membrane phase of the cells. This high oxygen partition coefficient into cell lipids has several consequences. Firstly oxygen diffusion will be directed and two dimensional rather than random and three dimensional. Secondly this diffusion will be directed towards the oxygen-consuming sites which are located at lipid surfaces. Thirdly the aqueous oxygen partial pressure will be kept low (since re-supply is constrained while consumption is continuous). This low aqueous environment permits all of the cell soluble redox systems to be maintained efficiently at low metabolic cost, as well as minimising the risk of unscheduled oxidations. Viewed from this perspective, the high value found for oxygen partition coefficient into the erythrocyte membrane suggests that evolution of membrane structure and components may have been driven in part by the selective advantages of high oxygen solubility.

  17. The effect of hyperbaric oxygen on severe anemia.

    PubMed

    Van Meter, Keith W

    2012-01-01

    As a respiratory pigment, hemoglobin allows blood to carry unnaturally high levels of nascent, molecular oxygen at one atmosphere of pressure in chemical solution to capillary beds and post-capillary venules supplying parenchymal cells of all organ systems in the body. When hemoglobin drops to critical levels to disallow proper oxygen delivery, hyperbaric oxygen therapy may be used as bridge therapy to emergently supply oxygen. Hyperbaric-administered oxygen allows oxygen to be dissolved in increased concentration in red blood cell-poor plasma or crystalloid/ colloid-diluted intravascular fluids in a volume-resuscitated patient. Additionally in both subacutely and chronically anemic patients, pulsed, intermittently provided normobaric or hyperbaric oxygen induces an increase in red blood cell/hemoglobic mass. Transfusions of separate donor red blood cells are transplantations of tissue not uncomplicated by immunomodulatory reactions. In the long term, autologous blood products may be less problematic than transfused, homologous packed red blood cells to reduce patient oxygen debt in illness or injury. Hyperbaric oxygen can reduce oxygen debt decisively in the polar clinical extremes of exsanguination with cardiopulmonary arrest all the way to resuscitation of the severely anemic patient who cannot be transfused with red blood cells for religious reasons, immunologic reasons, or blood availability problems. A hyperbaric oxygen treatment is equivalent in wholesale cost to a unit of packed red blood cells in the western world. By controversy, but true, hyperbaric oxygen provides a low-technology, cost-competitive means of pharmacologically reducing accumulated oxygen debt in the anemic, injured or critically ill patient with little side effect. To address severe anemia in trauma or illness, the future may well afford the use of hyperbaric oxygen therapy in the military far-forward, in pre-hospital EMS settings, in trauma center emergency departments, in operative and

  18. Titanium-Oxygen Reactivity Study

    NASA Technical Reports Server (NTRS)

    Chafey, J. E.; Scheck, W. G.; Witzell, W. E.

    1962-01-01

    A program has been conducted at Astronautics to investigate the likelihood of occurrence of the catastrophic oxidation of titanium alloy sheet under conditions which simulate certain cases of accidental failure of the metal while it is in contact with liquid or gaseous oxygen. Three methods of fracturing the metal were used; they consisted of mechanical puncture, tensile fracture of welded joints, and perforation by very high velocity particles. The results of the tests which have been conducted provide further evidence of the reactivity of titanium with liquid and gaseous oxygen. The evidence indicates that the rapid fracturing of titanium sheet while it is in contact with oxygen initiates the catastrophic oxidation reaction. Initiation occurred when the speed of the fracture was some few feet per second, as in both the drop-weight puncture tests and the static tensile fracture tests of welded joints, as well as when the speed was several thousand feet per second, as in the simulated micrometeoroid penetration tests. The slow propagation of a crack, however, did not initiate the reaction. It may logically be concluded that the localized frictional heat of rapid fracture and/or spontaneous oxidation (exothermic) of minute particles emanating from the fracture cause initiation of the reaction. Under conditions of slow fracture, however, the small heat generated may be adequately dissipated and the reaction is not initiated. A portion of the study conducted consisted of investigating various means by which the reaction might be retarded or prevented. Providing a "barrier" at the titanium-oxygen interface consisting of either aluminum metal or a coating of a petroleum base corrosion inhibitor appeared to be only partially effective in retarding the reaction. The accidental puncturing or similar rupturing of thin-walled pressurized oxygen tanks on missiles and space vehicle will usually constitute loss of function, and may sometimes cause their catastrophic destruction

  19. Oxygen chemisorption cryogenic refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1987-01-01

    The present invention relates to a chemisorption compressor cryogenic refrigerator which employs oxygen to provide cooling at 60 to 100 K. The invention includes dual vessels containing an oxygen absorbent material, alternately heated and cooled to provide a continuous flow of high pressure oxygen, multiple heat exchangers for precooling the oxygen, a Joule-Thomson expansion valve system for expanding the oxygen to partially liquefy it and a liquid oxygen pressure vessel. The primary novelty is that, while it was believed that once oxygen combined with an element or compound the reaction could not reverse to release gaseous oxygen, in this case oxygen will indeed react in a reversible fashion with certain materials and will do so at temperatures and pressures which make it practical for incorporation into a cryogenic refrigeration system.

  20. [Blood supply readiness in case of war or disasters].

    PubMed

    Fagerhol, M K; Dobloug, I

    1999-09-10

    The supply and use of blood during war or disaster require efficient cooperation between national and regional civilian authorities and blood banks as well as the military chain of command and medical units. Tasks and responsibilities are regulated by a directive issued by the Norwegian Armed Forces Joint Medical Services, specifying that during crises, civilian blood banks will be ordered to provide blood to military units. Based upon information obtained by a questionnaire survey, blood banks have an adequate capacity even if the normal power supply or computerised systems fail temporarily. However, plans are presently lacking for the organisation and operation of the civilian blood supply during a crisis requiring cooperation with military units. Key roles and responsibilities for personnel on the civilian side must be defined. Normal and alternative routes of communication must be established and tested regularly.

  1. On facilitated oxygen diffusion in muscle tissues.

    PubMed Central

    Fletcher, J E

    1980-01-01

    The role of myoglobin in facilitated diffusion of oxygen in muscle in examined in a tissue model that utilizes a central supplying capillary and a tissue cylinder concentric with the central capillary, and that includes the nonlinear characteristics of the oxygen-hemoglobin dissociation reaction. In contrast to previous work, this model exhibits the effect of blood flow and a realistic, though ideal, tissue-capillary geometry. Solutions of the model equations are obtained by a singular-perturbation technique, and numerical results are discussed for model parameters of physiologic interest. In contrast to the findings of Murray, Rubinow, Taylor, and others, fractional order perturbation terms obtained for the "boundary-layer" regions near the supplying capillaries are quite significant in the overall interpretation of the modeling results. Some closed solutions are found for special cases, and these are contrasted with the full singular-perturbation solution. Interpretations are given for parameters of physiologic interest. PMID:7295866

  2. Optoacoustic measurements of human placenta and umbilical blood oxygenation

    NASA Astrophysics Data System (ADS)

    Nanovskaya, T. N.; Petrov, I. Y.; Petrov, Y.; Patrikeeva, S. L.; Ahmed, M. S.; Hankins, G. D. V.; Prough, D. S.; Esenaliev, R. O.

    2016-03-01

    Adequate oxygenation is essential for normal embryogenesis and fetal growth. Perturbations in the intrauterine oxidative environment during pregnancy are associated with several pathophysiological disorders such as pregnancy loss, preeclampsia, and intrauterine growth restriction. We proposed to use optoacoustic technology for monitoring placental and fetal umbilical blood oxygenation. In this work, we studied optoacoustic monitoring of oxygenation in placenta and umbilical cord blood ex vivo using technique of placenta perfusion. We used a medical grade, nearinfrared, tunable, optoacoustic system developed and built for oxygenation monitoring in blood vessels and in tissues. First, we calibrated the system for cord blood oxygenation measurements by using a CO-Oximeter (gold standard). Then we performed validation in cord blood circulating through the catheters localized on the fetal side of an isolated placental lobule. Finally, the oxygenation measurements were performed in the perfused placental tissue. To increase or decrease blood oxygenation, we used infusion of a gas mixture of 95% O2 + 5% CO2 and 95% N2 + 5% CO2, respectively. In placental tissue, up to four cycles of changes in oxygenation were performed. The optoacoustically measured oxygenation in circulating cord blood and in placental lobule closely correlated with the actual oxygenation data measured by CO-Oximeter. We plan to further test the placental and cord blood oxygenation monitoring with optoacoustics in animal and clinical studies.

  3. Integrating the healthcare supply chain.

    PubMed

    Brennan, C D

    1998-01-01

    Today's integrated delivery systems (IDSs) require efficient supply chain processes to speed products to users at the lowest possible cost. Most excess costs within the supply chain are a result of inefficient and redundant processes involved in the transport and delivery of supplies from suppliers to healthcare providers. By integrating and assuming control of these supply chain processes, improving supply chain management practices, and organizing and implementing a disciplined redesign plan, IDSs can achieve substantial savings and better focus their organizations on their core patient care mission.

  4. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, W. J.

    2014-05-01

    Wim J. de Lange, Geert F. Prinsen, Jacco H. Hoogewoud, Ab A Veldhuizen, Joachim Hunink, Erik F.W. Ruijgh, Timo Kroon Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses

  5. Involving regional expertise in nationwide modeling for adequate prediction of climate change effects on different demands for fresh water

    NASA Astrophysics Data System (ADS)

    de Lange, Wim; Prinsen, Geert.; Hoogewoud, Jacco; Veldhuizen, Ab; Ruijgh, Erik; Kroon, Timo

    2013-04-01

    Nationwide modeling aims to produce a balanced distribution of climate change effects (e.g. harm on crops) and possible compensation (e.g. volume fresh water) based on consistent calculation. The present work is based on the Netherlands Hydrological Instrument (NHI, www.nhi.nu), which is a national, integrated, hydrological model that simulates distribution, flow and storage of all water in the surface water and groundwater systems. The instrument is developed to assess the impact on water use on land-surface (sprinkling crops, drinking water) and in surface water (navigation, cooling). The regional expertise involved in the development of NHI come from all parties involved in the use, production and management of water, such as waterboards, drinking water supply companies, provinces, ngo's, and so on. Adequate prediction implies that the model computes changes in the order of magnitude that is relevant to the effects. In scenarios related to drought, adequate prediction applies to the water demand and the hydrological effects during average, dry, very dry and extremely dry periods. The NHI acts as a part of the so-called Deltamodel (www.deltamodel.nl), which aims to predict effects and compensating measures of climate change both on safety against flooding and on water shortage during drought. To assess the effects, a limited number of well-defined scenarios is used within the Deltamodel. The effects on demand of fresh water consist of an increase of the demand e.g. for surface water level control to prevent dike burst, for flushing salt in ditches, for sprinkling of crops, for preserving wet nature and so on. Many of the effects are dealt with? by regional and local parties. Therefore, these parties have large interest in the outcome of the scenario analyses. They are participating in the assessment of the NHI previous to the start of the analyses. Regional expertise is welcomed in the calibration phase of NHI. It aims to reduce uncertainties by improving the

  6. Health Workforce: Ensuring Adequate Supply and Distribution Remains Challenging. Testimony before the Subcommittee on Health, Committee on Energy and Commerce, House of Representatives.

    ERIC Educational Resources Information Center

    Heinrich, Janet

    The General Accounting Office's (GAO's) director of health care-public health issues testified before Congress regarding growing concerns about the adequacy of the health care work force and lessons learned from the experience of the National Health Service Corps (NHSC) in addressing the maldistribution of health care professionals. The following…

  7. Enrollment of Blacks in College: Is the Supply of Black High School Graduates Adequate? Is the Demand for College by Blacks Weakening? Research and Development Update.

    ERIC Educational Resources Information Center

    Arbeiter, Solomon

    Factors that have affected the decline in black college enrollments in the 1980s are explored. Demographics of the teenage cohort during 1973-1983 are reviewed, and attributes of blacks and whites are compared to determine any significant changes among or between the black and white teenage populations that would account for the decline in black…

  8. Can Colleges and Universities Supply an Adequate Skilled Workforce for High Technology Needs in 1990? Problems, Prospects, and Policy for the Eighties. Research Report No. 82-27.

    ERIC Educational Resources Information Center

    Larkin, Paul

    Industry's needs for students with high technology skills are increasing. Bureau of Labor Statistics forecasts project increases between 1980 and 1990 of 58% in the demand for computer professionals, 28% for engineers, and 24% for engineering technicians, compared with an increase of 17% for all workers. Industrial expansion and replacement of…

  9. Factors controlling oxygen utilization.

    PubMed

    Biaglow, John; Dewhirst, Mark; Leeper, Dennis; Burd, Randy; Tuttle, Steve

    2005-01-01

    We demonstrate, theoretically, that oxygen diffusion distance is related to the metabolic rate of tumors (QO2) as well as the oxygen tension. The difference in QO2 rate between tumors can vary by as much as 80-fold. Inhibition of oxygen utilization by glucose or chemical inhibitors can improve the diffusion distance. Combining respiratory inhibitors with increased availability of oxygen will further improve the oxygen diffusion distance for all tumors. A simple means for inhibiting oxygen consumption is the use of glucose (the Crabtree effect). The inhibition of tumor oxygen utilization by glucose occurs in R323OAc mammary carcinoma and 9L glioma cells. However, stimulation of oxygen consumption is observed with glucose in the Q7 hepatoma cell line. MIBG, a known inhibitor of oxygen utilization, blocks oxygen consumption in 9L, but is weakly inhibitory with the Q7. Q7 tumor cells demonstrate an anomalous behavior of glucose and MIBG on oxygen consumption. Our results clearly demonstrate the necessity for comparing effects of different agents on different tumor cells. Generalizations cannot be made with respect to the choice of inhibitor for in vivo use. Our work shows that oxygen consumption also can be inhibited with malonate and chlorosuccinate. These substrates may be effective in vivo, where glucose is low and glutamine is the major substrate. Our results indicate that information about individual tumor substrate-linked metabolic controls may be necessary before attempting to inhibit oxygen utilization in vivo for therapeutic benefit.

  10. The concept of adequate causation and Max Weber's comparative sociology of religion.

    PubMed

    Buss, A

    1999-06-01

    Max Weber's The Protestant Ethic and the Spirit of Capitalism, studied in isolation, shows mainly an elective affinity or an adequacy on the level of meaning between the Protestant ethic and the 'spirit' of capitalism. Here it is suggested that Weber's subsequent essays on 'The Economic Ethics of World Religions' are the result of his opinion that adequacy on the level of meaning needs and can be verified by causal adequacy. After some introductory remarks, particularly on elective affinity, the paper tries to develop the concept of adequate causation and the related concept of objective possibility on the basis of the work of v. Kries on whom Weber heavily relied. In the second part, this concept is used to show how the study of the economic ethics of India, China, Rome and orthodox Russia can support the thesis that the 'spirit' of capitalism, although it may not have been caused by the Protestant ethic, was perhaps adequately caused by it.

  11. Ensuring smokers are adequately informed: reflections on consumer rights, manufacturer responsibilities, and policy implications

    PubMed Central

    Chapman, S; Liberman, J

    2005-01-01

    The right to information is a fundamental consumer value. Following the advent of health warnings, the tobacco industry has repeatedly asserted that smokers are fully informed of the risks they take, while evidence demonstrates widespread superficial levels of awareness and understanding. There remains much that tobacco companies could do to fulfil their responsibilities to inform smokers. We explore issues involved in the meaning of "adequately informed" smoking and discuss some of the key policy and regulatory implications. We use the idea of a smoker licensing scheme—under which it would be illegal to sell to smokers who had not demonstrated an adequate level of awareness—as a device to explore some of these issues. We also explore some of the difficulties that addiction poses for the notion that smokers might ever voluntarily assume the risks of smoking. PMID:16046703

  12. Industrial water supplies of the United States

    USGS Publications Warehouse

    Love, Samuel K.

    1954-01-01

    The availability of adequate supplies of water of suitable quality determines in large measure the potential for industrial development in any community. However, the pattern of availability of water for industrial use is not so generally recognized. It is the purpose of this paper to point out the more important factors affecting the distribution and quality of existing and potential sources of water with particular reference to industrial development. From a nation-wide standpoint our country is blessed with plenty of water. If the available water could be distributed completely in accordance with needs, it is probable that no part of the country would suffer from lack of water either now or in the foreseeable future. As nature has not dealt so providently however, or perhaps as man has not been able to cope with the vagaries of nature, we find ourselves beset with droughts and floods. Added to the natural deficiencies of nature are man-made difficulties such as lowered ground-water tables and salt-water encroachment of fresh water supplies resulting from overpumping of ground waters, pollution in all its forms, and wasteful use of water for many purposes. It becomes necessary, therefore, to study and evaluate our most important natural resource in order that we may use it more intelligently. This is particularly true in regard to continued industrial growth of our country.

  13. Myth 19: Is Advanced Placement an Adequate Program for Gifted Students?

    ERIC Educational Resources Information Center

    Gallagher, Shelagh A.

    2009-01-01

    Is it a myth that Advanced Placement (AP) is an adequate program for gifted students? AP is so covered with myths and assumptions that it is hard to get a clear view of the issues. In this article, the author finds the answer about AP by looking at current realties. First, AP is hard for gifted students to avoid. Second, AP never was a program…

  14. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries

    SciTech Connect

    Ryu, Won-Hee; Gittleson, Forrest S.; Thomsen, Julianne M.; Li, Jinyang; Schwab, Mark J.; Brudvig, Gary W.; Taylor, André D.

    2016-10-19

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. But, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. We show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme’s oxygen binding capability facilitates battery recharge by accepting and releasing dissociated oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. Our study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.

  15. Heme biomolecule as redox mediator and oxygen shuttle for efficient charging of lithium-oxygen batteries

    DOE PAGES

    Ryu, Won-Hee; Gittleson, Forrest S.; Thomsen, Julianne M.; ...

    2016-10-19

    One of the greatest challenges with lithium-oxygen batteries involves identifying catalysts that facilitate the growth and evolution of cathode species on an oxygen electrode. Heterogeneous solid catalysts cannot adequately address the problematic overpotentials when the surfaces become passivated. But, there exists a class of biomolecules which have been designed by nature to guide complex solution-based oxygen chemistries. We show that the heme molecule, a common porphyrin cofactor in blood, can function as a soluble redox catalyst and oxygen shuttle for efficient oxygen evolution in non-aqueous Li-O2 batteries. The heme’s oxygen binding capability facilitates battery recharge by accepting and releasing dissociatedmore » oxygen species while benefiting charge transfer with the cathode. We reveal the chemical change of heme redox molecules where synergy exists with the electrolyte species. Our study brings focus to the rational design of solution-based catalysts and suggests a sustainable cross-link between biomolecules and advanced energy storage.« less

  16. An oxygen slow-releasing material and its application in water remediation as oxygen supplier.

    PubMed

    Zhou, Yanbo; Fang, Xingbin; Zhang, Zhiqing; Hu, Yonghua; Lu, Jun

    2017-01-12

    In this study, an oxygen slow-releasing material (OSRM) consisting of calcium peroxide (CaO2), stearic acid (SA) and quartz sand was used to improve oxygen supply during bioremediation. The oxygen-releasing rates of CaO2 powder and OSRM with different SA contents were investigated. The efficacy of OSRM as an oxygen supplier was assessed by water remediation experiments using activated sludge. Results showed that CaO2 powder was effectively embedded by SA under anhydrous conditions. The oxygen-releasing rate decreased with increasing SA contents. Moreover, the OSRM exhibited higher oxygen-releasing capacity, and more effective pH control ability than CaO2 powder. The water remediation experiments showed better removal of COD and [Formula: see text] with OSRM as the oxygen supplier. These results provided detailed information when CaO2 was applied as the oxygen supplier in water remediation, which can serve as references for field application of bioremediation.

  17. Global risk assessment of aflatoxins in maize and peanuts: are regulatory standards adequately protective?

    PubMed

    Wu, Felicia; Stacy, Shaina L; Kensler, Thomas W

    2013-09-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America.

  18. Global Risk Assessment of Aflatoxins in Maize and Peanuts: Are Regulatory Standards Adequately Protective?

    PubMed Central

    Wu, Felicia

    2013-01-01

    The aflatoxins are a group of fungal metabolites that contaminate a variety of staple crops, including maize and peanuts, and cause an array of acute and chronic human health effects. Aflatoxin B1 in particular is a potent liver carcinogen, and hepatocellular carcinoma (HCC) risk is multiplicatively higher for individuals exposed to both aflatoxin and chronic infection with hepatitis B virus (HBV). In this work, we sought to answer the question: do current aflatoxin regulatory standards around the world adequately protect human health? Depending upon the level of protection desired, the answer to this question varies. Currently, most nations have a maximum tolerable level of total aflatoxins in maize and peanuts ranging from 4 to 20ng/g. If the level of protection desired is that aflatoxin exposures would not increase lifetime HCC risk by more than 1 in 100,000 cases in the population, then most current regulatory standards are not adequately protective even if enforced, especially in low-income countries where large amounts of maize and peanuts are consumed and HBV prevalence is high. At the protection level of 1 in 10,000 lifetime HCC cases in the population, however, almost all aflatoxin regulations worldwide are adequately protective, with the exception of several nations in Africa and Latin America. PMID:23761295

  19. Current strategies for the restoration of adequate lordosis during lumbar fusion.

    PubMed

    Barrey, Cédric; Darnis, Alice

    2015-01-18

    Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery.

  20. Current strategies for the restoration of adequate lordosis during lumbar fusion

    PubMed Central

    Barrey, Cédric; Darnis, Alice

    2015-01-01

    Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery. PMID:25621216

  1. A test for adequate wastewater treatment based on glutathione S transferase isoenzyme profile.

    PubMed

    Grammou, A; Samaras, P; Papadimitriou, C; Papadopoulos, A I

    2013-04-01

    Discharge to the environment of treated or non-treated municipal wastewater imposes several threats to coastal and estuarine ecosystems which are difficult to assess. In our study we evaluate the use of the isoenzyme profile of glutathione S transferase (GST) in combination with the kinetic characteristics of the whole enzyme and of heme peroxidase, as a test of adequate treatment of municipal wastewater. For this reason, Artemia nauplii were incubated in artificial seawater prepared by wastewater samples, such as secondary municipal effluents produced by a conventional activated sludge unit and advanced treated effluents produced by the employment of coagulation, activated carbon adsorption and chlorination as single processes or as combined ones. Characteristic changes of the isoenzyme pattern and the enzymes' kinetic properties were caused by chlorinated secondary municipal effluent or by secondary non-chlorinated effluent. Advanced treatment by combination of coagulation and/or carbon adsorption resulted to less prominent changes, suggesting more adequate treatment. Our results suggest that GST isoenzyme profile in combination with the kinetic properties of the total enzyme family is a sensitive test for the evaluation of the adequateness of the treatment of reclaimed wastewater and the reduction of potentially harmful compounds. Potentially, it may offer a 'fingerprint' characteristic of a particular effluent and probably of the treatment level it has been subjected.

  2. Hyperbaric oxygen therapy

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002375.htm Hyperbaric oxygen therapy To use the sharing features on this page, please enable JavaScript. Hyperbaric oxygen therapy uses a special pressure chamber to increase ...

  3. NNSA TRITIUM SUPPLY CHAIN

    SciTech Connect

    Wyrick, Steven; Cordaro, Joseph; Founds, Nanette; Chambellan, Curtis

    2013-08-21

    Savannah River Site plays a critical role in the Tritium Production Supply Chain for the National Nuclear Security Administration (NNSA). The entire process includes: • Production of Tritium Producing Burnable Absorber Rods (TPBARs) at the Westinghouse WesDyne Nuclear Fuels Plant in Columbia, South Carolina • Production of unobligated Low Enriched Uranium (LEU) at the United States Enrichment Corporation (USEC) in Portsmouth, Ohio • Irradiation of TPBARs with the LEU at the Tennessee Valley Authority (TVA) Watts Bar Reactor • Extraction of tritium from the irradiated TPBARs at the Tritium Extraction Facility (TEF) at Savannah River Site • Processing the tritium at the Savannah River Site, which includes removal of nonhydrogen species and separation of the hydrogen isotopes of protium, deuterium and tritium.

  4. Power Supply Unit

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Cuk DC to DC Switching Converter was developed by Caltech Professors, Slobodan Cuk and R. D. Middlebrook. The converter changes unsuitable dc voltage into one or more voltages suitable for powering electronic equipment; it can also be used in converting dc current to ac and vice versa. It was named one of the 100 most significant technical advances of 1979. The Cuk converter is more efficient than previous conversion devices, simpler, smaller, lighter, cheaper and highly reliable. The first application of the technology is in the Compucorp 685 word/data processor, manufactured by Compucorp. NASA waived title rights; Caltech granted exclusive license to the inventors, who in turn, transferred their rights to a company they founded called TESLA Company, which sublicenses the converter design and related technology to companies making power supplies for use in their own products.

  5. Stab water supply system

    SciTech Connect

    Hammett, D.S.

    1983-02-08

    Apparatus and method for fire suppression on offshore oil platforms including a stab receptacle on an outer surface of a platform connected to a fluid distribution system within the platform for distributing fire suppressing fluid to selected locations, a stab carrying a fluid conduit from a self-propelled service vessel, with the stab being in turn supported on a boom extending from the service vessel, a pumping system on the service vessel for supplying fire suppressing fluid through the conduit to the stab and thereby to the preselected locations. The service vessel is preferably a semi-submersible and includes a system for dynamic positioning of the vessel such as side thrusters in addition to a main propulsion unit.

  6. Sustainable Biomass Supply Systems

    SciTech Connect

    Erin Searcy; Dave Muth; Erin Wilkerson; Shahab Sokansanj; Bryan Jenkins; Peter Titman; Nathan Parker; Quinn Hart; Richard Nelson

    2009-04-01

    The U.S. Department of Energy (DOE) aims to displace 30% of the 2004 gasoline use (60 billion gal/yr) with biofuels by 2030 as outlined in the Energy Independence and Security Act of 2007, which will require 700 million tons of biomass to be sustainably delivered to biorefineries annually. Lignocellulosic biomass will make an important contribution towards meeting DOE’s ethanol production goals. For the biofuels industry to be an economically viable enterprise, the feedstock supply system (i.e., moving the biomass from the field to the refinery) cannot contribute more that 30% of the total cost of the biofuel production. The Idaho National Laboratory in collaboration with Oak Ridge National Laboratory, University of California, Davis and Kansas State University are developing a set of tools for identifying economical, sustainable feedstocks on a regional basis based on biorefinery siting.

  7. World petroleum supplies

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    A number of conclusions by political conservatives about the fate of world petroleum supplies have been emerging lately. Among the most recent of them arose from discussions, held at the 1983 spring meeting of the American Association for the Advancement of Science (AAAS), which focused on the environment and resource study entitled “The Global 2000 Report” (New Scientist, June 9, 1983). Fred Singer, representing the Heritage Foundation of Washington, D.C., criticized the report, which predicted shortages in the near future, saying that the current world-wide oil glut will continue beyond the year 2000. Alternatives to the use of petroleum are a part of the cause. Singer argued that conservation, nuclear energy, and other petroleum substitutes will continue to suppress the demand for petroleum. In addition, according to other evaluations, exploration for petroleum and natural gas has not really begun.

  8. Oxygen control with microfluidics.

    PubMed

    Brennan, Martin D; Rexius-Hall, Megan L; Elgass, Laura Jane; Eddington, David T

    2014-11-21

    Cellular function and behavior are affected by the partial pressure of O2, or oxygen tension, in the microenvironment. The level of oxygenation is important, as it is a balance of oxygen availability and oxygen consumption that is necessary to maintain normoxia. Changes in oxygen tension, from above physiological oxygen tension (hyperoxia) to below physiological levels (hypoxia) or even complete absence of oxygen (anoxia), trigger potent biological responses. For instance, hypoxia has been shown to support the maintenance and promote proliferation of regenerative stem and progenitor cells. Paradoxically, hypoxia also contributes to the development of pathological conditions including systemic inflammatory response, tumorigenesis, and cardiovascular disease, such as ischemic heart disease and pulmonary hypertension. Current methods to study cellular behavior in low levels of oxygen tension include hypoxia workstations and hypoxia chambers. These culture systems do not provide oxygen gradients that are found in vivo or precise control at the microscale. Microfluidic platforms have been developed to overcome the inherent limits of these current methods, including lack of spatial control, slow equilibration, and unachievable or difficult coupling to live-cell microscopy. The various applications made possible by microfluidic systems are the topic of this review. In order to understand how the microscale can be leveraged for oxygen control of cells and tissues within microfluidic systems, some background understanding of diffusion, solubility, and transport at the microscale will be presented in addition to a discussion on the methods for measuring the oxygen tension in microfluidic channels. Finally the various methods for oxygen control within microfluidic platforms will be discussed including devices that rely on diffusion from liquid or gas, utilizing on-or-off-chip mixers, leveraging cellular oxygen uptake to deplete the oxygen, relying on chemical reactions in

  9. Solid state oxygen sensor

    DOEpatents

    Garzon, Fernando H.; Brosha, Eric L.

    1997-01-01

    A potentiometric oxygen sensor is formed having a logarithmic response to a differential oxygen concentration while operating as a Nernstian-type sensor. Very thin films of mixed conducting oxide materials form electrode services while permitting diffusional oxygen access to the interface between the zirconia electrolyte and the electrode. Diffusion of oxygen through the mixed oxide is not rate-limiting. Metal electrodes are not used so that morphological changes in the electrode structure do not occur during extended operation at elevated temperatures.

  10. Oxygen evolution reaction catalysis

    DOEpatents

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  11. Oxygen enriched combustion system performance study. Phase 2: 100 percent oxygen enriched combustion in regenerative glass melters, Final report

    SciTech Connect

    Tuson, G.B.; Kobayashi, H.; Campbell, M.J.

    1994-08-01

    The field test project described in this report was conducted to evaluate the energy and environmental performance of 100% oxygen enriched combustion (100% OEC) in regenerative glass melters. Additional objectives were to determine other impacts of 100% OEC on melter operation and glass quality, and to verify on a commercial scale that an on-site Pressure Swing Adsorption oxygen plant can reliably supply oxygen for glass melting with low electrical power consumption. The tests constituted Phase 2 of a cooperative project between the United States Department of Energy, and Praxair, Inc. Phase 1 of the project involved market and technical feasibility assessments of oxygen enriched combustion for a range of high temperature industrial heating applications. An assessment of oxygen supply options for these applications was also performed during Phase 1, which included performance evaluation of a pilot scale 1 ton per day PSA oxygen plant. Two regenerative container glass melters were converted to 100% OEC operation and served as host sites for Phase 2. A 75 ton per day end-fired melter at Carr-Lowrey Glass Company in Baltimore, Maryland, was temporarily converted to 100% OEC in mid- 1990. A 350 tpd cross-fired melter at Gallo Glass Company in Modesto, California was rebuilt for permanent commercial operation with 100% OEC in mid-1991. Initially, both of these melters were supplied with oxygen from liquid storage. Subsequently, in late 1992, a Pressure Swing Adsorption oxygen plant was installed at Gallo to supply oxygen for 100% OEC glass melting. The particular PSA plant design used at Gallo achieves maximum efficiency by cycling the adsorbent beds between pressurized and evacuated states, and is therefore referred to as a Vacuum/Pressure Swing Adsorption (VPSA) plant.

  12. Oxygen sensitive microwells.

    PubMed

    Sinkala, Elly; Eddington, David T

    2010-12-07

    Oxygen tension is critical in a number of cell pathways but is often overlooked in cell culture. One reason for this is the difficulty in modulating and assessing oxygen tensions without disturbing the culture conditions. Toward this end, a simple method to generate oxygen-sensitive microwells was developed through embossing polystyrene (PS) and platinum(ii) octaethylporphyrin ketone (PtOEPK) thin films. In addition to monitoring the oxygen tension, microwells were employed in order to isolate uniform clusters of cells in microwells. The depth and width of the microwells can be adapted to different experimental parameters easily by altering the thin film processing or embossing stamp geometries. The thin oxygen sensitive microwell substrate is also compatible with high magnification modalities such as confocal imaging. The incorporation of the oxygen sensor into the microwells produces measurements of the oxygen tension near the cell surface. The oxygen sensitive microwells were calibrated and used to monitor oxygen tensions of Madin-Darby Canine Kidney Cells (MDCKs) cultured at high and low densities as a proof of concept. Wells 500 µm in diameter seeded with an average of 330 cells exhibited an oxygen level of 12.6% whereas wells seeded with an average of 20 cells per well exhibited an oxygen level of 19.5%, a 35.7% difference. This platform represents a new tool for culturing cells in microwells in a format amenable to high magnification imaging while monitoring the oxygen state of the culture media.

  13. Indicators: Dissolved Oxygen

    EPA Pesticide Factsheets

    Dissolved oxygen (DO) is the amount of oxygen that is present in water. It is an important measure of water quality as it indicates a water body's ability to support aquatic life. Water bodies receive oxygen from the atmosphere and from aquatic plants.

  14. Hypoxemia (Low Blood Oxygen)

    MedlinePlus

    Symptoms Hypoxemia (low blood oxygen) By Mayo Clinic Staff Hypoxemia is a below-normal level of oxygen in your blood, specifically in the arteries. Hypoxemia ... of breath. Hypoxemia is determined by measuring the oxygen level in a blood sample taken from an ...

  15. Reduced and reversed temperature dependence of blood oxygenation in an ectothermic scombrid fish: implications for the evolution of regional heterothermy?

    PubMed

    Clark, Timothy Darren; Rummer, J L; Sepulveda, C A; Farrell, A P; Brauner, C J

    2010-01-01

    Tunas (family Scombridae) are exceptional among most teleost fishes in that they possess vascular heat exchangers which allow heat retention in specific regions of the body (termed 'regional heterothermy'). Seemingly exclusive to heterothermic fishes is a markedly reduced temperature dependence of blood-oxygen (blood-O(2)) binding, or even a reversed temperature dependence where increasing temperature increases blood-O(2) affinity. These unusual binding properties have been documented in whole blood and in haemoglobin (Hb) solutions, and they are hypothesised to prevent oxygen loss from arteries to veins within the vascular heat exchangers and/or to prevent excessive oxygen unloading to the warm tissues and ensure an adequate supply of oxygen to tissues positioned efferent to the heat exchangers. The temperature sensitivity of blood-O(2) binding has not been characterised in an ectothermic scombrid (mackerels and bonitos), but the existence of the unusual binding properties in these fishes would have clear implications for their proposed association with regional heterothermy. Accordingly, the present study examined oxygenation of whole blood of the chub mackerel (Scomber japonicus) at 10, 20 and 30 degrees C and at 0.5, 1 and 2% CO(2). Oxygen affinity was generally highest at 20 degrees C for all levels of CO(2). Temperature-independent binding was observed at low (0.5%) CO(2), where the PO(2) at 50% blood-O(2) saturation (P (50)) was not statistically different at 10 and 30 degrees C (2.58 vs. 2.78 kPa, respectively) with an apparent heat of oxygenation (H degrees ) close to zero (-6 kJ mol(-1)). The most significant temperature-mediated difference occurred at high (2%) CO(2), where the P (50) at 10 degrees C was twofold higher than that at 20 degrees C with a corresponding H degrees of +43 kJ mol(-1). These results provide clear evidence of independent and reversed open-system temperature effects on blood oxygenation in S. japonicus, and it is therefore

  16. Patterns of dissolved oxygen dynamics in a Pacific Northwest slough and tide channel.

    EPA Science Inventory

    Pacific Northwest (PNW) estuaries and tide channels are habitats or migratory corridors for societally prized salmonids. These fish have high oxygen requirements, and an adequate level of dissolved oxygen is considered an important gauge of a PNW water body’s condition. W...

  17. Patterns of dissolved oxygen dynamics in a Pacific Northwest slough and tide channel - CERF 2015

    EPA Science Inventory

    Pacific Northwest (PNW) estuaries and tide channels are habitats or migratory corridors for societally prized salmonids. These fish have high oxygen requirements, and an adequate level of dissolved oxygen is considered an important gauge of a PNW water body’s condition. W...

  18. Oxygen delivery, consumption, and conversion to reactive oxygen species in experimental models of diabetic retinopathy

    PubMed Central

    Eshaq, Randa S.; Wright, William S.; Harris, Norman R.

    2014-01-01

    Retinal tissue receives its supply of oxygen from two sources – the retinal and choroidal circulations. Decreases in retinal blood flow occur in the early stages of diabetes, with the eventual development of hypoxia thought to contribute to pathological neovascularization. Oxygen consumption in the retina has been found to decrease in diabetes, possibly due to either a reduction in neuronal metabolism or to cell death. Diabetes also enhances the rate of conversion of oxygen to superoxide in the retina, with experimental evidence suggesting that mitochondrial superoxide not only drives the overall production of reactive oxygen species, but also initiates several pathways leading to retinopathy, including the increased activity of the polyol and hexosamine pathways, increased production of advanced glycation end products and expression of their receptors, and activation of protein kinase C. PMID:24936440

  19. Oxygen production by pyrolysis of lunar regolith

    NASA Technical Reports Server (NTRS)

    Senior, Constance L.

    1991-01-01

    Oxygen was identified as the most important product of initial lunar materials processing efforts. A source of oxygen on the Moon provides an alternative to the costly transport of propellant to the Moon or to low earth orbit. Pyrolysis, or vapor-phase reduction, involves heating a feedstock to temperatures sufficient to decompose the constituent metal oxides and release oxygen. The process relies on the vaporization of metal oxides in the form of reduced suboxides or atomic species. The reduced species must then be condensed without re-oxidizing, yielding oxygen in the gas phase. The feasibility of obtaining oxygen from common lunar minerals was demonstrated using solar furnace experiments. These results are discussed together with chemical equilibrium models which were extended to include the multicomponent oxides used in experiments. For the first time, both experiments and theoretical models dealt with the complex oxides that make up potential lunar feedstocks. Two major conclusions are drawn from this preliminary work. First, unbeneficiated regolith is a suitable feedstock for pyrolysis. Second, the process can operate at moderate temperatures, circa 2000 K, which could be supplied by direct solar or electrical energy. In addition to these advantages in choice of feedstock and energy source, the pyrolysis process requires no chemicals or reagents, making it an attractive process for lunar oxygen production.

  20. Developing sustainable food supply chains.

    PubMed

    Smith, B Gail

    2008-02-27

    This paper reviews the opportunities available for food businesses to encourage consumers to eat healthier and more nutritious diets, to invest in more sustainable manufacturing and distribution systems and to develop procurement systems based on more sustainable forms of agriculture. The important factors in developing more sustainable supply chains are identified as the type of supply chain involved and the individual business attitude to extending responsibility for product quality into social and environmental performance within their own supply chains. Interpersonal trust and working to standards are both important to build more sustainable local and many conserved food supply chains, but inadequate to transform mainstream agriculture and raw material supplies to the manufactured and commodity food markets. Cooperation among food manufacturers, retailers, NGOs, governmental and farmers' organizations is vital in order to raise standards for some supply chains and to enable farmers to adopt more sustainable agricultural practices.

  1. Combustion of bulk titanium in oxygen

    NASA Technical Reports Server (NTRS)

    Clark, A. F.; Moulder, J. C.; Runyan, C. C.

    1975-01-01

    The combustion of bulk titanium in one atmosphere oxygen is studied using laser ignition and several analytical techniques. These were high-speed color cinematography, time and space resolved spectra in the visible region, metallography (including SEM) of specimens quenched in argon gas, X-ray and chemical product analyses, and a new optical technique, the Hilbert transform method. The cinematographic application of this technique for visualizing phase objects in the combustion zone is described. The results indicate an initial vapor phase reaction immediately adjacent to the molten surface but as the oxygen uptake progresses the evaporation approaches the point of congruency and a much reduced evaporation rate. This and the accumulation of the various soluble oxides soon drive the reaction zone below the surface where gas formation causes boiling and ejection of particles. The buildup of rutile cuts off the oxygen supply and the reaction ceases.

  2. Lunar oxygen production by pyrolysis of regolith

    NASA Technical Reports Server (NTRS)

    Senior, Constance L.

    1991-01-01

    Oxygen represents one of the most desirable products of lunar mining and manufacturing. Among the many processes which have been proposed for oxygen production, pyrolysis stands out as one which is uncomplicated and easy to bootstrap. Pyrolysis or vapor-phase reduction involves heating regolith to temperatures sufficient to allow partial decomposition and vaporization. Some metal oxides give up oxygen upon heating, either in the gas phase to form reduced gaseous species or in the condensed phase to form a metallic phase. Based on preliminary experiments and equilibrium calculations, the temperatures needed for pyrolysis are expected to be in the range of 2000 to 2200 K, giving total gas pressures of 0.001 to 0.1 torr. Bulk regolith can be used as a feedstock without beneficiation with concentrated solar radiation supplying most of energy needed. Further, selective condensation of metal-containing species from the gas phase may yield metallic iron and silicon as byproducts.

  3. Oxygen and the production of formazan from neotetrazolium chloride.

    PubMed

    Butcher, R G

    1978-07-12

    Electrons, generated from dehydrogenase reactions, are transferred to oxygen in preference to neotetrazolium chloride. In model systems in solution the presence of a small amount of oxygen drastically reduces the rate of formazan production. The rate of reaction in tissue sections has been followed using scanning and integrating microdensitometry. As in solution, electrons are transferred preferentially to oxygen. However, oxygen seems unable to diffuse through the incubation medium and thus the supply of oxygen at the site of the enzyme activity becomes exhausted; the time taken to use up the oxygen will depend on the rate of the enzyme activity. It is only then that electrons are passed to the tetrazolium salt and formazan is precipitated.

  4. Reliability Estimates for Power Supplies

    SciTech Connect

    Lee C. Cadwallader; Peter I. Petersen

    2005-09-01

    Failure rates for large power supplies at a fusion facility are critical knowledge needed to estimate availability of the facility or to set priorties for repairs and spare components. A study of the "failure to operate on demand" and "failure to continue to operate" failure rates has been performed for the large power supplies at DIII-D, which provide power to the magnet coils, the neutral beam injectors, the electron cyclotron heating systems, and the fast wave systems. When one of the power supplies fails to operate, the research program has to be either temporarily changed or halted. If one of the power supplies for the toroidal or ohmic heating coils fails, the operations have to be suspended or the research is continued at de-rated parameters until a repair is completed. If one of the power supplies used in the auxiliary plasma heating systems fails the research is often temporarily changed until a repair is completed. The power supplies are operated remotely and repairs are only performed when the power supplies are off line, so that failure of a power supply does not cause any risk to personnel. The DIII-D Trouble Report database was used to determine the number of power supply faults (over 1,700 reports), and tokamak annual operations data supplied the number of shots, operating times, and power supply usage for the DIII-D operating campaigns between mid-1987 and 2004. Where possible, these power supply failure rates from DIII-D will be compared to similar work that has been performed for the Joint European Torus equipment. These independent data sets support validation of the fusion-specific failure rate values.

  5. Mimicking Oxygen delivery and waste removal functions of blood.

    PubMed

    Zhang, Huaifa; Barralet, Jake E

    2017-02-15

    In addition to immunological and wound healing cell and platelet delivery, ion stasis and nutrient supply, blood delivers oxygen to cells and tissues and removes metabolic wastes. For decades researchers have been trying to develop approaches that mimic these two immediately vital functions of blood. Oxygen is crucial for the long-term survival of tissues and cells in vertebrates. Hypoxia (oxygen deficiency) and even at times anoxia (absence of oxygen) can occur during organ preservation, organ and cell transplantation, wound healing, in tumors and engineering of tissues. Different approaches have been developed to deliver oxygen to tissues and cells, including hyperbaric oxygen therapy (HBOT), normobaric hyperoxia therapy (NBOT), using biochemical reactions and electrolysis, employing liquids with high oxygen solubility, administering hemoglobin, myoglobin and red blood cells (RBCs), introducing oxygen-generating agents, using oxygen-carrying microparticles, persufflation, and peritoneal oxygenation. Metabolic waste accumulation is another issue in biological systems when blood flow is insufficient. Metabolic wastes change the microenvironment of cells and tissues, influence the metabolic activities of cells, and ultimately cause cell death. This review examines advances in blood mimicking systems in the field of biomedical engineering in terms of oxygen delivery and metabolic waste removal.

  6. Cholangiocytes and blood supply

    PubMed Central

    Gaudio, Eugenio; Franchitto, Antonio; Pannarale, Luigi; Carpino, Guido; Alpini, Gianfranco; Francis, Heather; Glaser, Shannon; Alvaro, Domenico; Onori, Paolo

    2006-01-01

    The microvascular supply of the biliary tree, the peribiliary plexus (PBP), stems from the hepatic artery branches and flows into the hepatic sinusoids. A detailed three-dimensional study of the PBP has been performed by using the Scanning Electron Microscopy vascular corrosion casts (SEMvcc) technique. Considering that the PBP plays a fundamental role in supporting the secretory and absorptive functions of the biliary epithelium, their organization in either normalcy and pathology is explored. The normal liver shows the PBP arranged around extra- and intrahepatic biliary tree. In the small portal tract PBP was characterized by a single layer of capillaries which progressively continued with the extrahepatic PBP where it showed a more complex vascular network. After common duct ligation (BDL), progressive modifications of bile duct and PBP proliferation are observed. The PBP presents a three-dimensional network arranged around many bile ducts and appears as bundles of vessels, composed by capillaries of homogeneous diameter with a typical round mesh structure. The PBP network is easily distinguishable from the sinusoidal network which appears normal. Considering the enormous extension of the PBP during BDL, the possible role played by the Vascular Endothelial Growth Factor (VEGF) is evaluated. VEGF-A, VEGF-C and their related receptors appeared highly immunopositive in proliferating cholangiocytes of BDL rats. The administration of anti-VEGF-A or anti-VEGF-C antibodies to BDL rats as well as hepatic artery ligation induced a reduced bile duct mass. The administration of rVEGF-A to BDL hepatic artery ligated rats prevented the decrease of cholangiocyte proliferation and VEGF-A expression as compared to BDL control rats. These data suggest the role of arterial blood supply of the biliary tree in conditions of cholangiocyte proliferation, such as it occurs during chronic cholestasis. On the other hand, the role played by VEGF as a tool of cross-talk between

  7. [Oxygen in the field hospitals: current experience in the military health service].

    PubMed

    Rouvier, B; Dupeyron, C; Carpentier, J P; Evrard, P

    1998-01-01

    A fifty per cent oxygen ratio locks quite sufficient for putting at sleep war wounded patient. After the present time, every french field surgical structures are equipped with oxygen extractors. Furthermore, those teams have at heir disposal for several years, oxygen generators, working with sodium chlorate candels. Those one can fill oxygen cylinders (3.5 l at 90 or 150 bars), providing pure oxygen, which will ever be essential under exceptional conditions. During war period, the supply difficulties demand to have at disposal two different production capabilities for oxygen administration.

  8. Singlet oxygen in photosensitization.

    PubMed

    Moan, Johan; Juzenas, Petras

    2006-01-01

    Oxygen is a ubiquitous element and a vitally important substance for life on the Earth, and especially for human life. Living organisms need oxygen for most, if not all, of their cellular functions. On the other hand, oxygen can produce metabolites that are toxic and potentially lethal to the same cells. Being reactive and chemically unstable reactive oxygen species (ROS) are the most important metabolites that initiate reduction and oxidation (redox) reactions under physiological conditions. Oxygen in its excited singlet state (1O2) is probably the most important intermediate in such reactions. Since the discovery of oxygen by Joseph Priestley in 1775 it has been recognized that oxygen can be both beneficial and harmful to life.

  9. Oxygen partial pressure sensor

    DOEpatents

    Dees, D.W.

    1994-09-06

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured. 1 fig.

  10. Oxygen partial pressure sensor

    DOEpatents

    Dees, Dennis W.

    1994-01-01

    A method for detecting oxygen partial pressure and an oxygen partial pressure sensor are provided. The method for measuring oxygen partial pressure includes contacting oxygen to a solid oxide electrolyte and measuring the subsequent change in electrical conductivity of the solid oxide electrolyte. A solid oxide electrolyte is utilized that contacts both a porous electrode and a nonporous electrode. The electrical conductivity of the solid oxide electrolyte is affected when oxygen from an exhaust stream permeates through the porous electrode to establish an equilibrium of oxygen anions in the electrolyte, thereby displacing electrons throughout the electrolyte to form an electron gradient. By adapting the two electrodes to sense a voltage potential between them, the change in electrolyte conductivity due to oxygen presence can be measured.

  11. Oxygen, ecology, and the Cambrian radiation of animals

    NASA Astrophysics Data System (ADS)

    Sperling, Erik A.; Frieder, Christina A.; Raman, Akkur V.; Girguis, Peter R.; Levin, Lisa A.; Knoll, Andrew H.

    2013-08-01

    The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator-prey "arms races" can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation.

  12. Oxygen, ecology, and the Cambrian radiation of animals.

    PubMed

    Sperling, Erik A; Frieder, Christina A; Raman, Akkur V; Girguis, Peter R; Levin, Lisa A; Knoll, Andrew H

    2013-08-13

    The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator-prey "arms races" can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation.

  13. Are the current Australian sun exposure guidelines effective in maintaining adequate levels of 25-hydroxyvitamin D?

    PubMed

    Kimlin, Michael; Sun, Jiandong; Sinclair, Craig; Heward, Sue; Hill, Jane; Dunstone, Kimberley; Brodie, Alison

    2016-01-01

    An adequate vitamin D status, as measured by serum 25-hydroxyvitamin D (25(OH)D) concentration, is important in humans for maintenance of healthy bones and muscle function. Serum 25(OH)D concentration was assessed in participants from Melbourne, Australia (37.81S, 144.96E), who were provided with the current Australian guidelines on sun exposure for 25(OH)D adequacy (25(OH)D ≥50 nmol/L). Participants were interviewed in February (summer, n=104) and August (winter, n=99) of 2013. Serum 25(OH)D concentration was examined as a function of measures of sun exposure and sun protection habits with control of key characteristics such as dietary intake of vitamin D, body mass index (BMI) and skin colour, that may modify this relationship. The mean 25(OH)D concentration in participants who complied with the current sun exposure guidelines was 67.3 nmol/L in summer and 41.9 nmol/L in winter. At the end of the study, 69.3% of participants who complied with the summer sun exposure guidelines were 25(OH)D adequate, while only 27.6% of participants who complied with the winter sun exposure guidelines were 25(OH)D adequate at the end of the study. The results suggest that the current Australian guidelines for sun exposure for 25(OH)D adequacy are effective for most in summer and ineffective for most in winter. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  14. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    PubMed Central

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  15. The Nigerian health care system: Need for integrating adequate medical intelligence and surveillance systems

    PubMed Central

    Welcome, Menizibeya Osain

    2011-01-01

    Objectives: As an important element of national security, public health not only functions to provide adequate and timely medical care but also track, monitor, and control disease outbreak. The Nigerian health care had suffered several infectious disease outbreaks year after year. Hence, there is need to tackle the problem. This study aims to review the state of the Nigerian health care system and to provide possible recommendations to the worsening state of health care in the country. To give up-to-date recommendations for the Nigerian health care system, this study also aims at reviewing the dynamics of health care in the United States, Britain, and Europe with regards to methods of medical intelligence/surveillance. Materials and Methods: Databases were searched for relevant literatures using the following keywords: Nigerian health care, Nigerian health care system, and Nigerian primary health care system. Additional keywords used in the search were as follows: United States (OR Europe) health care dynamics, Medical Intelligence, Medical Intelligence systems, Public health surveillance systems, Nigerian medical intelligence, Nigerian surveillance systems, and Nigerian health information system. Literatures were searched in scientific databases Pubmed and African Journals OnLine. Internet searches were based on Google and Search Nigeria. Results: Medical intelligence and surveillance represent a very useful component in the health care system and control diseases outbreak, bioattack, etc. There is increasing role of automated-based medical intelligence and surveillance systems, in addition to the traditional manual pattern of document retrieval in advanced medical setting such as those in western and European countries. Conclusion: The Nigerian health care system is poorly developed. No adequate and functional surveillance systems are developed. To achieve success in health care in this modern era, a system well grounded in routine surveillance and medical

  16. Fuel cell power supply with oxidant and fuel gas switching

    DOEpatents

    McElroy, J.F.; Chludzinski, P.J.; Dantowitz, P.

    1987-04-14

    This invention relates to a fuel cell vehicular power plant. Fuel for the fuel stack is supplied by a hydrocarbon (methanol) catalytic cracking reactor and CO shift reactor. A water electrolysis subsystem is associated with the stack. During low power operation part of the fuel cell power is used to electrolyze water with hydrogen and oxygen electrolysis products being stored in pressure vessels. During peak power intervals, viz, during acceleration or start-up, pure oxygen and pure hydrogen from the pressure vessel are supplied as the reaction gases to the cathodes and anodes in place of air and methanol reformate. This allows the fuel cell stack to be sized for normal low power/air operation but with a peak power capacity several times greater than that for normal operation. 2 figs.

  17. Fuel cell power supply with oxidant and fuel gas switching

    DOEpatents

    McElroy, James F.; Chludzinski, Paul J.; Dantowitz, Philip

    1987-01-01

    This invention relates to a fuel cell vehicular power plant. Fuel for the fuel stack is supplied by a hydrocarbon (methanol) catalytic cracking reactor and CO shift reactor. A water electrolysis subsystem is associated with the stack. During low power operation part of the fuel cell power is used to electrolyze water with hydrogen and oxygen electrolysis products being stored in pressure vessels. During peak power intervals, viz, during acceleration or start-up, pure oxygen and pure hydrogen from the pressure vessel are supplied as the reaction gases to the cathodes and anodes in place of air and methanol reformate. This allows the fuel cell stack to be sized for normal low power/air operation but with a peak power capacity several times greater than that for normal operation.

  18. Sustainability issues in rural water supply in Asia.

    PubMed

    1998-03-01

    This article identifies some sustainability issues in management of water supplies in rural Asia. The International Drinking Water Supply and Sanitation Decade was 1981-90. At present, less than 50% of the rural population in several Asian countries have access to safe water, and even less have access to adequate sanitation. Access does not ensure quality of services or supplies. Data on coverage is inadequate and does not take into account water quality, hours of service, reliability of supplies, distance to the source, and community use patterns. It is difficult to improve access to the poor. There is no single uniform strategy that works for all parts of a country. Countries need to promote community management that has strategic vision and appropriate priorities. Local management is constrained by centralized authority, the orientation of sector agencies, and staff with weak managerial, financial, technical, and communications skills. Many countries lack resources to maintain water delivery infrastructures and to prevent deterioration of services. There is a need to develop low cost appropriate technologies, management requirements, health education, community participation, mobilization of women, and synergistic, nonsequential development. Demand for water and sanitation is driven by survival and privacy issues. Rural water supply programs should view water as an economic and social good. Water management is effective when decisions are made locally. Local governments need to be strengthened in order to be able to perform demand management, select institutional options, and to take care of the unserviced.

  19. Nebulized antibiotics. An adequate option for treating ventilator-associated respiratory infection?

    PubMed

    Rodríguez, A; Barcenilla, F

    2015-03-01

    Ventilator-associated tracheobronchitis (VAT) is a frequent complication in critical patients. The 90% of those who develop it receive broad-spectrum antibiotic (ATB) treatment, without any strong evidence of its favorable impact. The use of nebulized ATB could be a valid treatment option, to reduce the use of systemic ATB and the pressure of selection on the local flora. Several studies suggest that an adequate nebulization technique can ensure high levels of ATB even in areas of lung consolidation, and to obtain clinical and microbiological cure. New studies are needed to properly assess the impact of treatment with nebulized ATB on the emergence of resistance.

  20. Computer synthesis of human motion as a part of an adequate motion analysis experiment

    NASA Astrophysics Data System (ADS)

    Ivanov, Alexandre A.; Sholukha, Victor A.; Zinkovsky, Anatoly V.

    1999-05-01

    The role of problem of computer synthesis of a human motion for a traditional problem of control generalized and muscular forces determination is discussed. It is emphasized significance of computer model choice for adequate analysis kinematic and dynamic experimental data. On the basis of an imitation computer model influence of model's parameters values is demonstrated. With help of non-stationary constraints we can simulate human motions that satisfy to the most significant parameters of the concerned class of motion. Some results of simulation are discussed. We arrive at a conclusion that for correct interpretation of an experiment mixed problem of bodies system dynamics must be solved.