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Sample records for higher respiration rate

  1. What controls respiration rate in stored sugarbeet roots

    Science.gov (United States)

    Although respiration is estimated to be responsible for 60 to 80% of the sucrose lost during storage, the mechanisms by which sugarbeet roots regulate their respiration rate are unknown. In plants, respiration rate is regulated by (1) available respiratory capacity, (2) cellular energy status, (3) ...

  2. Redefinition and global estimation of basal ecosystem respiration rate

    DEFF Research Database (Denmark)

    Yuan, Wenping; Luo, Yiqi; Li, Xianglan

    2011-01-01

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models sti...

  3. Thermal effects on growth and respiration rates of the mayfly, Dolania americana (ephemeroptera)

    International Nuclear Information System (INIS)

    Harvey, R.S.

    1975-01-01

    The mayfly Dolania Americana, common in the sand of Upper Three Runs Creek, Savannah River Plant, was studied to determine the effects of seasonal changes in temperature on population growth rates and to determine the effects of slight elevations in water temperature on respiration rates of this benthic species. Growth of the population increased with stream temperature until peak emergence of adults in June and July. There was a strong inverse correlation between body weight and respiration rates of immature nymphs. Respiration rates at 2.5, 5, and 10 0 C above ambient creekwater temperatures were not significantly higher than those measured at ambient creekwater temperatures. (auth)

  4. Redefinition and global estimation of basal ecosystem respiration rate

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Wenping [College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; Luo, Yiqi [Department of Botany and Microbiology, University of Oklahoma, Norman, Oklahoma, USA; Li, Xianglan [College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; Liu, Shuguang; Yu, Guirui [Key Laboratory of Ecosystem Network Observation and Modeling, Synthesis Research Center of Chinese Ecosystem Research Network, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Zhou, Tao [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing, China; Bahn, Michael [Institute of Ecology, University of Innsbruck, Innsbruck, Austria; Black, Andy [Faculty of Land and Food Systems, University of British Columbia, Vancouver, B. C., Canada; Desai, Ankur R. [Atmospheric and Oceanic Sciences Department, Center for Climatic Research, Nelson Institute for Environmental Studies, University of Wisconsin-Madison, Madison, Wisconsin, USA; Cescatti, Alessandro [Institute for Environment and Sustainability, Joint Research Centre, European Commission, Ispra, Italy; Marcolla, Barbara [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Jacobs, Cor [Alterra, Earth System Science-Climate Change, Wageningen University, Wageningen, Netherlands; Chen, Jiquan [Department of Earth, Ecological, and Environmental Sciences, University of Toledo, Toledo, Ohio, USA; Aurela, Mika [Climate and Global Change Research, Finnish Meteorological Institute, Helsinki, Finland; Bernhofer, Christian [Chair of Meteorology, Institute of Hydrology and Meteorology, Technische Universität Dresden, Dresden, Germany; Gielen, Bert [Department of Biology, University of Antwerp, Wilrijk, Belgium; Bohrer, Gil [Department of Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, Ohio, USA; Cook, David R. [Climate Research Section, Environmental Science Division, Argonne National Laboratory, Argonne, Illinois, USA; Dragoni, Danilo [Department of Geography, Indiana University, Bloomington, Indiana, USA; Dunn, Allison L. [Department of Physical and Earth Sciences, Worcester State College, Worcester, Massachusetts, USA; Gianelle, Damiano [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Grünwald, Thomas [Chair of Meteorology, Institute of Hydrology and Meteorology, Technische Universität Dresden, Dresden, Germany; Ibrom, Andreas [Risø DTU National Laboratory for Sustainable Energy, Biosystems Division, Technical University of Denmark, Roskilde, Denmark; Leclerc, Monique Y. [Department of Crop and Soil Sciences, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA; Lindroth, Anders [Geobiosphere Science Centre, Physical Geography and Ecosystems Analysis, Lund University, Lund, Sweden; Liu, Heping [Laboratory for Atmospheric Research, Department of Civil and Environmental Engineering, Washington State University, Pullman, Washington, USA; Marchesini, Luca Belelli [Department for Innovation in Biological, Agro-Food and Forest Systems, University of Tuscia, Viterbo, Italy; Montagnani, Leonardo; Pita, Gabriel [Department of Mechanical Engineering, Instituto Superior Técnico, Lisbon, Portugal; Rodeghiero, Mirco [Sustainable Agro-ecosystems and Bioresources Department, Fondazione Edmund Mach-IASMA Research and Innovation Centre, San Michele all' Adige, Italy; Rodrigues, Abel [Unidade de Silvicultura e Produtos Florestais, Instituto Nacional dos Recursos Biológicos, Oeiras, Portugal; Starr, Gregory [Department of Biological Sciences, University of Alabama, Tuscaloosa, Alabama, USA; Stoy, Paul C. [Department of Land Resources and Environmental Sciences, Montana State University, Bozeman, Montana, USA

    2011-10-13

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models still use a global constant BR largely due to the lack of a functional description for BR. In this study, we redefined BR to be ecosystem respiration rate at the mean annual temperature. To test the validity of this concept, we conducted a synthesis analysis using 276 site-years of eddy covariance data, from 79 research sites located at latitudes ranging from ~3°S to ~70°N. Results showed that mean annual ER rate closely matches ER rate at mean annual temperature. Incorporation of site-specific BR into global ER model substantially improved simulated ER compared to an invariant BR at all sites. These results confirm that ER at the mean annual

  5. Soil respiration patterns and rates at three Taiwanese forest plantations: dependence on elevation, temperature, precipitation, and litterfall.

    Science.gov (United States)

    Huang, Yu-Hsuan; Hung, Chih-Yu; Lin, I-Rhy; Kume, Tomonori; Menyailo, Oleg V; Cheng, Chih-Hsin

    2017-11-15

    Soil respiration contributes to a large quantity of carbon emissions in the forest ecosystem. In this study, the soil respiration rates at three Taiwanese forest plantations (two lowland and one mid-elevation) were investigated. We aimed to determine how soil respiration varies between lowland and mid-elevation forest plantations and identify the relative importance of biotic and abiotic factors affecting soil respiration. The results showed that the temporal patterns of soil respiration rates were mainly influenced by soil temperature and soil water content, and a combined soil temperature and soil water content model explained 54-80% of the variation. However, these two factors affected soil respiration differently. Soil temperature positively contributed to soil respiration, but a bidirectional relationship between soil respiration and soil water content was revealed. Higher soil moisture content resulted in higher soil respiration rates at the lowland plantations but led to adverse effects at the mid-elevation plantation. The annual soil respiration rates were estimated as 14.3-20.0 Mg C ha -1  year -1 at the lowland plantations and 7.0-12.2 Mg C ha -1  year -1 at the mid-elevation plantation. When assembled with the findings of previous studies, the annual soil respiration rates increased with the mean annual temperature and litterfall but decreased with elevation and the mean annual precipitation. A conceptual model of the biotic and abiotic factors affecting the spatial and temporal patterns of the soil respiration rate was developed. Three determinant factors were proposed: (i) elevation, (ii) stand characteristics, and (iii) soil temperature and soil moisture. The results indicated that changes in temperature and precipitation significantly affect soil respiration. Because of the high variability of soil respiration, more studies and data syntheses are required to accurately predict soil respiration in Taiwanese forests.

  6. Two Proximal Skin Electrodes — A Respiration Rate Body Sensor

    Directory of Open Access Journals (Sweden)

    Viktor Avbelj

    2012-10-01

    Full Text Available We propose a new body sensor for extracting the respiration rate based on the amplitude changes in the body surface potential differences between two proximal body electrodes. The sensor could be designed as a plaster-like reusable unit that can be easily fixed onto the surface of the body. It could be equipped either with a sufficiently large memory for storing the measured data or with a low-power radio system that can transmit the measured data to a gateway for further processing. We explore the influence of the sensor’s position on the quality of the extracted results using multi-channel ECG measurements and considering all the pairs of two neighboring electrodes as potential respiration-rate sensors. The analysis of the clinical measurements, which also include reference thermistor-based respiration signals, shows that the proposed approach is a viable option for monitoring the respiration frequency and for a rough classification of breathing types. The obtained results were evaluated on a wireless prototype of a respiration body sensor. We indicate the best positions for the respiration body sensor and prove that a single sensor for body surface potential difference on proximal skin electrodes can be used for combined measurements of respiratory and cardiac activities.

  7. Redefinition and global estimation of basal ecosystem respiration rate

    Science.gov (United States)

    Yuan, W.; Luo, Y.; Li, X.; Liu, S.; Yu, G.; Zhou, T.; Bahn, M.; Black, A.; Desai, A.R.; Cescatti, A.; Marcolla, B.; Jacobs, C.; Chen, J.; Aurela, M.; Bernhofer, C.; Gielen, B.; Bohrer, G.; Cook, D.R.; Dragoni, D.; Dunn, A.L.; Gianelle, D.; Grnwald, T.; Ibrom, A.; Leclerc, M.Y.; Lindroth, A.; Liu, H.; Marchesini, L.B.; Montagnani, L.; Pita, G.; Rodeghiero, M.; Rodrigues, A.; Starr, G.; Stoy, Paul C.

    2011-01-01

    Basal ecosystem respiration rate (BR), the ecosystem respiration rate at a given temperature, is a common and important parameter in empirical models for quantifying ecosystem respiration (ER) globally. Numerous studies have indicated that BR varies in space. However, many empirical ER models still use a global constant BR largely due to the lack of a functional description for BR. In this study, we redefined BR to be ecosystem respiration rate at the mean annual temperature. To test the validity of this concept, we conducted a synthesis analysis using 276 site-years of eddy covariance data, from 79 research sites located at latitudes ranging from ∼3°S to ∼70°N. Results showed that mean annual ER rate closely matches ER rate at mean annual temperature. Incorporation of site-specific BR into global ER model substantially improved simulated ER compared to an invariant BR at all sites. These results confirm that ER at the mean annual temperature can be considered as BR in empirical models. A strong correlation was found between the mean annual ER and mean annual gross primary production (GPP). Consequently, GPP, which is typically more accurately modeled, can be used to estimate BR. A light use efficiency GPP model (i.e., EC-LUE) was applied to estimate global GPP, BR and ER with input data from MERRA (Modern Era Retrospective-Analysis for Research and Applications) and MODIS (Moderate resolution Imaging Spectroradiometer). The global ER was 103 Pg C yr −1, with the highest respiration rate over tropical forests and the lowest value in dry and high-latitude areas.

  8. Aquatic respiration rate measurements at low oxygen concentrations.

    Directory of Open Access Journals (Sweden)

    Moritz Holtappels

    Full Text Available Despite its huge ecological importance, microbial oxygen respiration in pelagic waters is little studied, primarily due to methodological difficulties. Respiration measurements are challenging because of the required high resolution of oxygen concentration measurements. Recent improvements in oxygen sensing techniques bear great potential to overcome these limitations. Here we compare 3 different methods to measure oxygen consumption rates at low oxygen concentrations, utilizing amperometric Clark type sensors (STOX, optical sensors (optodes, and mass spectrometry in combination with (18-18O2 labeling. Oxygen concentrations and consumption rates agreed well between the different methods when applied in the same experimental setting. Oxygen consumption rates between 30 and 400 nmol L(-1 h(-1 were measured with high precision and relative standard errors of less than 3%. Rate detection limits in the range of 1 nmol L(-1 h(-1 were suitable for rate determinations in open ocean water and were lowest at the lowest applied O2 concentration.

  9. Effects of elevated CO2 leaf diets on gypsy moth (Lepidoptera: Lymantriidae) respiration rates.

    Science.gov (United States)

    Foss, Anita R; Mattson, William J; Trier, Terry M

    2013-06-01

    Elevated levels of CO2 affect plant growth and leaf chemistry, which in turn can alter host plant suitability for insect herbivores. We examined the suitability of foliage from trees grown from seedlings since 1997 at Aspen FACE as diet for the gypsy moth (Lymantria dispar L.) Lepidoptera: Lymantriidae: paper birch (Betula papyrifera Marshall) in 2004-2005, and trembling aspen (Populus tremuloides Michaux) in 2006-2007, and measured consequent effects on larval respiration. Leaves were collected for diet and leaf chemistry (nutritional and secondary compound proxies) from trees grown under ambient (average 380 ppm) and elevated CO2 (average 560 ppm) conditions. Elevated CO2 did not significantly alter birch or aspen leaf chemistry compared with ambient levels with the exception that birch percent carbon in 2004 and aspen moisture content in 2006 were significantly lowered. Respiration rates were significantly higher (15-59%) for larvae reared on birch grown under elevated CO2 compared with ambient conditions, but were not different on two aspen clones, until larvae reached the fifth instar, when those consuming elevated CO2 leaves on clone 271 had lower (26%) respiration rates, and those consuming elevated CO2 leaves on clone 216 had higher (36%) respiration rates. However, elevated CO2 had no apparent effect on the respiration rates of pupae derived from larvae fed either birch or aspen leaves. Higher respiration rates for larvae fed diets grown under ambient or elevated CO2 demonstrates their lower efficiency of converting chemical energy of digested food stuffs extracted from such leaves into their biosynthetic processes.

  10. Microbiopsies versus Bergström needle for skeletal muscle sampling: impact on maximal mitochondrial respiration rate.

    Science.gov (United States)

    Isner-Horobeti, M E; Charton, A; Daussin, F; Geny, B; Dufour, S P; Richard, R

    2014-05-01

    Microbiopsies are increasingly used as an alternative to the standard Bergström technique for skeletal muscle sampling. The potential impact of these two different procedures on mitochondrial respiration rate is unknown. The objective of this work was to compare microbiopsies versus Bergström procedure on mitochondrial respiration in skeletal muscle. 52 vastus lateralis muscle samples were obtained from 13 anesthetized pigs, either with a Bergström [6 gauges (G)] needle or with microbiopsy needles (12, 14, 18G). Maximal mitochondrial respiration (V GM-ADP) was assessed using an oxygraphic method on permeabilized fibers. The weight of the muscle samples and V GM-ADP decreased with the increasing gauge of the needles. A positive nonlinear relationship was observed between the weight of the muscle sample and the level of maximal mitochondrial respiration (r = 0.99, p respiration (r = 0.99, p respiration compared to the standard Bergström needle.Therefore, the higher the gauge (i.e. the smaller the size) of the microbiopsy needle, the lower is the maximal rate of respiration. Microbiopsies of skeletal muscle underestimate the maximal mitochondrial respiration rate, and this finding needs to be highlighted for adequate interpretation and comparison with literature data.

  11. Accuracy of acoustic respiration rate monitoring in pediatric patients.

    Science.gov (United States)

    Patino, Mario; Redford, Daniel T; Quigley, Thomas W; Mahmoud, Mohamed; Kurth, C Dean; Szmuk, Peter

    2013-12-01

    Rainbow acoustic monitoring (RRa) utilizes acoustic technology to continuously and noninvasively determine respiratory rate from an adhesive sensor located on the neck. We sought to validate the accuracy of RRa, by comparing it to capnography, impedance pneumography, and to a reference method of counting breaths in postsurgical children. Continuous respiration rate data were recorded from RRa and capnography. In a subset of patients, intermittent respiration rate from thoracic impedance pneumography was also recorded. The reference method, counted respiratory rate by the retrospective analysis of the RRa, and capnographic waveforms while listening to recorded breath sounds were used to compare respiration rate of both capnography and RRa. Bias, precision, and limits of agreement of RRa compared with capnography and RRa and capnography compared with the reference method were calculated. Tolerance and reliability to the acoustic sensor and nasal cannula were also assessed. Thirty-nine of 40 patients (97.5%) demonstrated good tolerance of the acoustic sensor, whereas 25 of 40 patients (62.5%) demonstrated good tolerance of the nasal cannula. Intermittent thoracic impedance produced erroneous respiratory rates (>50 b·min(-1) from the other methods) on 47% of occasions. The bias ± SD and limits of agreement were -0.30 ± 3.5 b·min(-1) and -7.3 to 6.6 b·min(-1) for RRa compared with capnography; -0.1 ± 2.5 b·min(-1) and -5.0 to 5.0 b·min(-1) for RRa compared with the reference method; and 0.2 ± 3.4 b·min(-1) and -6.8 to 6.7 b·min(-1) for capnography compared with the reference method. When compared to nasal capnography, RRa showed good agreement and similar accuracy and precision but was better tolerated in postsurgical pediatric patients. © 2013 John Wiley & Sons Ltd.

  12. A novel hardware implementation for detecting respiration rate using photoplethysmography.

    Science.gov (United States)

    Prinable, Joseph; Jones, Peter; Thamrin, Cindy; McEwan, Alistair

    2017-07-01

    Asthma is a serious public health problem. Continuous monitoring of breathing may offer an alternative way to assess disease status. In this paper we present a novel hardware implementation for the capture and storage of a photoplethysmography (PPG) signal. The LED duty cycle was altered to determine the effect on respiratory rate accuracy. The oximeter was mounted to the left index finger of ten healthy volunteers. The breathing rate derived from the oximeter was validated against a nasal airflow sensor. The duty cycle of a pulse oximeter was changed between 5%, 10% and 25% at a sample rate of 500 Hz. A PPG signal and reference signal was captured for each duty cycle. The PPG signals were post processed in Matlab to derive a respiration rate using an existing Matlab toolbox. At a 25% duty cycle the RMSE was <;2 breaths per minute for the top performing algorithm. The RMSE increased to over 5 breaths per minute when the duty cycle was reduced to 5%. The power consumed by the hardware for a 5%, 10% and 25% duty cycle was 5.4 mW, 7.8 mW, and 15 mW respectively. For clinical assessment of respiratory rate, a RSME of <;2 breaths per minute is recommended. Further work is required to determine utility in asthma management. However for non-clinical applications such as fitness tracking, lower accuracy may be sufficient to allow a reduced duty cycle setting.

  13. Glycolysis Is Dynamic and Relates Closely to Respiration Rate in Stored Sugarbeet Roots

    Directory of Open Access Journals (Sweden)

    Clarice A. Megguer

    2017-05-01

    Full Text Available Although respiration is the principal cause of the loss of sucrose in postharvest sugarbeet (Beta vulgaris L., the internal mechanisms that control root respiration rate are unknown. Available evidence, however, indicates that respiration rate is likely to be controlled by the availability of respiratory substrates, and glycolysis has a central role in generating these substrates. To determine glycolytic changes that occur in sugarbeet roots after harvest and to elucidate relationships between glycolysis and respiration, sugarbeet roots were stored for up to 60 days, during which activities of glycolytic enzymes and concentrations of glycolytic substrates, intermediates, cofactors, and products were determined. Respiration rate was also determined, and relationships between respiration rate and glycolytic enzymes and metabolites were evaluated. Glycolysis was highly variable during storage, with 10 of 14 glycolytic activities and 14 of 17 glycolytic metabolites significantly altered during storage. Changes in glycolytic enzyme activities and metabolites occurred throughout the 60 day storage period, but were greatest in the first 4 days after harvest. Positive relationships between changes in glycolytic enzyme activities and root respiration rate were abundant, with 10 of 14 enzyme activities elevated when root respiration was elevated and 9 glycolytic activities static during periods of unchanging respiration rate. Major roles for pyruvate kinase and phosphofructokinase in the regulation of postharvest sugarbeet root glycolysis were indicated based on changes in enzymatic activities and concentrations of their substrates and products. Additionally, a strong positive relationship between respiration rate and pyruvate kinase activity was found indicating that downstream TCA cycle enzymes were unlikely to regulate or restrict root respiration in a major way. Overall, these results establish that glycolysis is not static during sugarbeet root

  14. [Effects of simulated acid rain on respiration rate of cropland system with different soil pH].

    Science.gov (United States)

    Zhu, Xue-zhu; Zhang, Gao-chuan; Li, Hui

    2009-10-15

    To evaluate the effects of acid rain on the respiration rate of cropland system, an outdoor pot experiment was conducted with paddy soils of pH 5.48 (S1), pH 6.70 (S1) and pH 8.18 (S3) during the 2005-2007 wheat-growing seasons. The cropland system was exposed to acid rain by spraying the wheat foliage and irrigating the soil with simulated rainwater of T1 (pH 6.0), T2 (pH 6.0, ionic concentration was twice as rainwater T1), and T3 (pH 4.4, ionic concentration was twice as rainwater T1), respectively. The static opaque chamber-gas chromatograph method was used to measure CO2 fluxes from cropland system. The results showed that acid rain affected the respiration rate of cropland system through crop plant, and the cropland system could adapt to acid rain. Acid rainwater significantly increased the average respiration rate in alkaline soil (S3) cropland system, while it had no significant effects on the average respiration rate in neutral soil (S2) and acidic soil (S1) cropland systems. During 2005-2006, after the alkaline soil cropland system was treated with rainwater T3, the average respiration rate was 23.6% and 27.6% higher than that of alkaline soil cropland system treated with rainwater T1 and T2, respectively. During March to April, the respiration rate was enhanced with the increase of rainwater ionic concentration, while it was dropped with the decrease of rainwater pH value in acidic soil cropland system. It was demonstrated that soil pH and crop plant played important roles on the respiration rate of cropland system.

  15. Respiration rate and ethylene production of fresh cut lettuce as affected by cutting grade

    Directory of Open Access Journals (Sweden)

    J. MARTÍNEZ

    2008-12-01

    Full Text Available For designing optimal polymeric films for modified atmosphere packaging of whole heads as well as for minimally fresh processed (fresh-cut Iceberg lettuce ‘Coolguard’, the effect of several cutting grades on respiration rate (RR and ethylene production at 5ºC was studied. According to common industrial practices cutting grades less than 0.5 cm, between 0.5 and 1 cm, and 2 cm length were selected. Results from four experiments were compared to those obtained for whole heads in which a homogenous range of 6 to 8 ml CO2 kg-1 h-1 in RR was found. Compared to whole heads, in fresh-cut lettuce the RR was 2-fold higher. The lowest cutting grade showed the highest respiration rate, and no significant differences in RR among lettuce pieces of intermediate and the highest grades were found. No ethylene production was detected in whole heads, while in minimally processed lettuce pieces only traces were found. For avoiding risks of anaerobic respiration and excessive CO2 levels within packages containing fresh-cut lettuce pieces lower than 0.5 cm length, films with relatively high O2 permeability like standard polypropylene or low-density polyethylene must be selected.;

  16. Oxygen respiration rates of benthic foraminifera as measured with oxygen microsensors

    DEFF Research Database (Denmark)

    Geslin, E.; Risgaard-Petersen, N.; Lombard, Fabien

    2011-01-01

    of the foraminiferal specimens. The results show a wide range of oxygen respiration rates for the different species (from 0.09 to 5.27 nl cell−1 h−1) and a clear correlation with foraminiferal biovolume showed by the power law relationship: R = 3.98 10−3 BioVol0.88 where the oxygen respiration rate (R) is expressed......Oxygen respiration rates of benthic foraminifera are still badly known, mainly because they are difficult to measure. Oxygen respiration rates of seventeen species of benthic foraminifera were measured using microelectrodes and calculated on the basis of the oxygen fluxes measured in the vicinity...... groups (nematodes, copepods, ostracods, ciliates and flagellates) suggests that benthic foraminifera have a lower oxygen respiration rates per unit biovolume. The total contribution of benthic foraminifera to the aerobic mineralisation of organic matter is estimated for the studied areas. The results...

  17. Estimation of microbial respiration rates in groundwater by geochemical modeling constrained with stable isotopes

    International Nuclear Information System (INIS)

    Murphy, E.M.

    1998-01-01

    Changes in geochemistry and stable isotopes along a well-established groundwater flow path were used to estimate in situ microbial respiration rates in the Middendorf aquifer in the southeastern United States. Respiration rates were determined for individual terminal electron acceptors including O 2 , MnO 2 , Fe 3+ , and SO 4 2- . The extent of biotic reactions were constrained by the fractionation of stable isotopes of carbon and sulfur. Sulfur isotopes and the presence of sulfur-oxidizing microorganisms indicated that sulfate is produced through the oxidation of reduced sulfur species in the aquifer and not by the dissolution of gypsum, as previously reported. The respiration rates varied along the flow path as the groundwater transitioned between primarily oxic to anoxic conditions. Iron-reducing microorganisms were the largest contributors to the oxidation of organic matter along the portion of the groundwater flow path investigated in this study. The transition zone between oxic and anoxic groundwater contained a wide range of terminal electron acceptors and showed the greatest diversity and numbers of culturable microorganisms and the highest respiration rates. A comparison of respiration rates measured from core samples and pumped groundwater suggests that variability in respiration rates may often reflect the measurement scales, both in the sample volume and the time-frame over which the respiration measurement is averaged. Chemical heterogeneity may create a wide range of respiration rates when the scale of the observation is below the scale of the heterogeneity

  18. Continuous daylight in the high-Arctic summer supports high plankton respiration rates compared to those supported in the dark

    KAUST Repository

    Mesa, Elena

    2017-04-21

    Plankton respiration rate is a major component of global CO2 production and is forecasted to increase rapidly in the Arctic with warming. Yet, existing assessments in the Arctic evaluated plankton respiration in the dark. Evidence that plankton respiration may be stimulated in the light is particularly relevant for the high Arctic where plankton communities experience continuous daylight in spring and summer. Here we demonstrate that plankton community respiration evaluated under the continuous daylight conditions present in situ, tends to be higher than that evaluated in the dark. The ratio between community respiration measured in the light (Rlight) and in the dark (Rdark) increased as the 2/3 power of Rlight so that the Rlight:Rdark ratio increased from an average value of 1.37 at the median Rlight measured here (3.62 µmol O2 L-1 d-1) to an average value of 17.56 at the highest Rlight measured here (15.8 µmol O2 L-1 d-1). The role of respiratory processes as a source of CO2 in the Arctic has, therefore, been underestimated and is far more important than previously believed, particularly in the late spring, with 24 h photoperiods, when community respiration rates are highest.

  19. Changes in respiration rates and biomass attributes of epilithon due to extended exposure to zinc

    International Nuclear Information System (INIS)

    Colwell, F.S.

    1986-01-01

    The purpose of this research was to determine the influence of extended dosing of zinc on the carbon cycling and biomass characteristics of freshwater epilithon. Experiments were conducted in artificial streams continuously dosed with 0.00, 0.05, or 1.00 mg Zn liter -1 for 20 to 30 days during summer and fall, 1984 and 1985. Repeated measurement of epilithon structure and function included estimates of 14 C-glucose respiration, 14 C-glutamate respiration, O 2 and CO 2 flux rates, ash-free dry weight (AFDW), protein, carbohydrate, and algal pigment concentrations, and total and zinc-tolerant colony forming units. An increase in epilithic glucose respiration per unit biomass consistently occurred 5 to 10 days after dosing with 1.0 mg Zn liter -1 was started. At the same time significantly lower epilithon biomass occurred in the high dosed streams relative to controls in 3 out of 4 studies. Although algal pigment concentrations were lowest in the high dose streams at the midpoint of the studies, the chlorophyll a-to-pheophytin a ratio remained high, indicating that the minimal algal population was not senescing in situ. After 30 days, the epilithon dosed with 1.0 mg Zn liter -1 had higher AFDW, protein, and carbohydrate concentrations than the other treatments. The development of unique epilithon communities that are acclimated to prolonged zinc exposure is evident in the eventual recolonization of the artificial surfaces, glucose respiration rates that are comparable to controls, and presence of zinc-tolerant heterotrophs

  20. Production, oxygen respiration rates, and sinking velocity of copepod fecal pellets: Direct measurements of ballasting by opal and calcite

    DEFF Research Database (Denmark)

    Ploug, H.; Iversen, M.H.; Koski, Marja

    2008-01-01

    sp., T. weissflogii, and E. huxleyi, respectively. The average carbon-specific respiration rate was 0.15 d(-1) independent on diet (range: 0.08-0.21 d(-1)). Because of ballasting of opal and calcite, sinking velocities were significantly higher for pellets produced on T. weissflogii (322 +/- 169 m d...

  1. [Design of Oxygen Saturation, Heart Rate, Respiration Rate Detection System Based on Smartphone of Android Operating System].

    Science.gov (United States)

    Zhu, Mingshan; Zeng, Bixin

    2015-03-01

    In this paper, we designed an oxygen saturation, heart rate, respiration rate monitoring system based on smartphone of android operating system, physiological signal acquired by MSP430 microcontroller and transmitted by Bluetooth module.

  2. Measurement and Modeling of Respiration Rate of Tomato (Cultivar Roma) for Modified Atmosphere Storage.

    Science.gov (United States)

    Kandasamy, Palani; Moitra, Ranabir; Mukherjee, Souti

    2015-01-01

    Experiments were conducted to determine the respiration rate of tomato at 10, 20 and 30 °C using closed respiration system. Oxygen depletion and carbon dioxide accumulation in the system containing tomato was monitored. Respiration rate was found to decrease with increasing CO2 and decreasing O2 concentration. Michaelis-Menten type model based on enzyme kinetics was evaluated using experimental data generated for predicting the respiration rate. The model parameters that obtained from the respiration rate at different O2 and CO2 concentration levels were used to fit the model against the storage temperatures. The fitting was fair (R2 = 0.923 to 0.970) when the respiration rate was expressed as O2 concentation. Since inhibition constant for CO2 concentration tended towards negetive, the model was modified as a function of O2 concentration only. The modified model was fitted to the experimental data and showed good agreement (R2 = 0.998) with experimentally estimated respiration rate.

  3. Soil respiration and rates of soil carbon turnover differ among six common European tree species

    DEFF Research Database (Denmark)

    Vesterdal, Lars; Elberling, Bo; Christiansen, Jesper Riis

    2012-01-01

    replicated at six sites in Denmark. The studied tree species were the broadleaves beech (Fagus sylvatica L.), pedunculate oak (Quercus robur L.), lime (Tilia cordata L.), sycamore maple (Acer pseudoplatanus L.) and ash (Fraxinus excelsior L.) and the conifer Norway spruce (Picea abies (L.) Karst.). Rates....... Soil respiration differed significantly among several species and increased in the order beechmaple... moisture. Carbon turnover rates based on the ratio between R h and C stock were significantly higher in ash than in all other species except maple, and maple also had higher C turnover than spruce. A similar influence of tree species on C turnover was indicated by the litterfall C to forest floor C ratio...

  4. Influence of forced respiration on nonlinear dynamics in heart rate variability

    DEFF Research Database (Denmark)

    Kanters, J K; Højgaard, M V; Agner, E

    1997-01-01

    Although it is doubtful whether the normal sinus rhythm can be described as low-dimensional chaos, there is evidence for inherent nonlinear dynamics and determinism in time series of consecutive R-R intervals. However, the physiological origin for these nonlinearities is unknown. The aim...... with a metronome set to 12 min(-1). Nonlinear dynamics were measured as the correlation dimension and the nonlinear prediction error. Complexity expressed as correlation dimension was unchanged from normal respiration, 9.1 +/- 0.5, compared with forced respiration, 9.3 +/- 0.6. Also, nonlinear determinism...... expressed as the nonlinear prediction error did not differ between spontaneous respiration, 32.3 +/- 3.4 ms, and forced respiration, 31.9 +/- 5.7. It is concluded that the origin of the nonlinear dynamics in heart rate variability is not a nonlinear input from the respiration into the cardiovascular...

  5. Airborne release fractions/rates and respirable fractions for nonreactor nuclear facilities. Volume 2, Appendices

    International Nuclear Information System (INIS)

    1994-12-01

    This document contains compiled data from the DOE Handbook on Airborne Release Fractions/Rates and Respirable Fractions for Nonreactor Nuclear facilities. Source data and example facilities utilized, such as the Plutonium Recovery Facility, are included

  6. Landscape Influences on Potential Soil Respiration Rates in a Forested Watershed of Southeastern Kentucky

    Science.gov (United States)

    Amanda C. Abnee; James A. Thompson; Randall K. Kolka; Elisa M. D' Angelo; Mark S. Coyne

    2004-01-01

    Soil respiration measurements conducted in the laboratory have been shown to be related to temperature and moisture, with maximum rates at soil temperatures between 25 and 40°C and soil moisture between -0.01 and -0.10 MPa. A preliminary study using forest soils from eastern Kentucky supported the previous research with soil respiration rates greater at 25°C than at 15...

  7. Continuous daylight in the high-Arctic summer supports high plankton respiration rates compared to those supported in the dark

    KAUST Repository

    Mesa, Elena; Delgado-Huertas, Antonio; Carrillo-de-Albornoz, Paloma; Garcí a-Corral, Lara S.; Sanz-Martí n, Marina; Wassmann, Paul; Reigstad, Marit; Sejr, Mikael; Dalsgaard, Tage; Duarte, Carlos M.

    2017-01-01

    Plankton respiration rate is a major component of global CO2 production and is forecasted to increase rapidly in the Arctic with warming. Yet, existing assessments in the Arctic evaluated plankton respiration in the dark. Evidence that plankton

  8. Respiration rate of stream insects measured in situ along a large altitude range

    DEFF Research Database (Denmark)

    Rostgaard, S.; Jacobsen, D.

    2005-01-01

    Field studies of respiration in stream insects are few in comparison with laboratory studies. To evaluate the influence of temperature and oxygen along altitudinal gradients we measured the respiration rate of fully acclimatized larval Trichoptera, Plecoptera and Ephemeroptera under similar field...... at 100 and 50% oxygen saturation indicated that highland animals reduced their oxygen uptake more than their counterparts in the lowland when oxygen availability decreased. The temperature response of respiration calculated between the insect assemblages at different altitudes showed a mean assemblage Q...

  9. Influence of gamma irradiation, cold storage and pulsing on post harvest life and respiration rate of 'golden gate' cut roses

    International Nuclear Information System (INIS)

    Palanikumar, S.; Vinod Kumar; Bhattacharjee, S.K.; Pal, Madan

    2003-01-01

    Gamma irradiation at 0.025 kGy increased the respiration rate of 'Golden Gate' cut roses. The irradiation followed by cold storage (at 4 deg C) brought down the respiration rate after storage duration of 3 days. The respiration rate was found maximum in the sucrose (3% ) pulsed flowers immediately after pulsing. However, the rate of respiration is decreased in all the treatments. The irradiated flowers recorded lowest amount of respiration at senescence and the vase life was maximum in these flowers. (author)

  10. Soil respiration rate on the contrasting north- and south-facing slopes of a larch forest in central Siberia

    International Nuclear Information System (INIS)

    Yanagihara, Y.; Koike, T.; Matsuura, Y.; Mori, S.; Shibata, H.; Satoh, F.; Masuyagina, O.V.; Zyryanova, O.A.; Prokushkin, A.S.; Prokushkin, S.G.; Abaimov, A.P.

    2000-01-01

    In an attempt to evaluate global warming effects, we measured the soil respiration of the contrasting north- and south- facing slopes of a larch forest in central Siberia, located at Tura City in the Krasnoyarsk District, Russia. The north-facing slope is assumed to be the present condition while the south-facing slope may stand for the future warm condition. As a result of differences in solar radiation, there were clear differences between the north- and south- facing slopes in terms, for example, of the active layer as the growth rate of larch trees. The soil respiration rate was higher on the south-facing slope than on the north-facing slope. At the temperature of 15°C, soil respiration rate of the south-facing slope was ca. 6.2 μ mol CO 2 * m -2 s -1 , which was about 0.6 times lower than that of broad-leaved forests in Hokkaido. There was an exponential correlation between soil temperature at 10 cm depth and the efflux of CO 2 from the soil surface. Various conditions (soil temperature,. nitrogen content and soil water content) seemed to be more favorable for soil respiration on the south-facing slope. (author)

  11. Data compilation of respiration, feeding, and growth rates of marine pelagic organisms

    DEFF Research Database (Denmark)

    2013-01-01

    's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from...

  12. Soil respiration patterns and rates at three Taiwanese forest plantations: dependence on elevation, temperature, precipitation, and litterfall

    OpenAIRE

    Huang, Yu-Hsuan; Hung, Chih-Yu; Lin, I-Rhy; Kume, Tomonori; Menyailo, Oleg V.; Cheng, Chih-Hsin

    2017-01-01

    Background Soil respiration contributes to a large quantity of carbon emissions in the forest ecosystem. In this study, the soil respiration rates at three Taiwanese forest plantations (two lowland and one mid-elevation) were investigated. We aimed to determine how soil respiration varies between lowland and mid-elevation forest plantations and identify the relative importance of biotic and abiotic factors affecting soil respiration. Results The results showed that the temporal patterns of so...

  13. No diurnal variation in rate or carbon isotope composition of soil respiration in a boreal forest

    International Nuclear Information System (INIS)

    Betson, N.R.; Gottlicher, S.G.; Hogberg, P.; Hall, M.; Wallin, G.; Richter, A.

    2007-01-01

    This study evaluated the diurnal variability in the rate and stable carbon isotope ratio ((delta) 13 C) of soil respiration in a northern boreal forest, measured with opaque chambers after the removal of understory vegetation. The experiment was conducted in June and August 2004 at the Picea abies L. Karst-dominated Flakaliden Research Forest in northern Sweden, using unfertilized girdled-tree plots and unfertilized non-girdled tree plots. Soil respiration and (delta) 13 C of soil-respired carbon dioxide (CO 2 ) were measured every 4 hours on 6 plots, with a total of 11 sampling times over each 48 hour period. The purpose was to clarify an earlier study regarding the origin of diurnal patterns of soil CO 2 flux. This study explored whether the diurnal patterns were the result of photosynthetic CO 2 uptake during the day by the understory or whether there were underlying trends in soil respiration driven by plant root allocation. The sampling campaigns undertaken in this study investigated whether diurnal variations in soil respiration rate and (delta) 13 C exist in this ecosystem when no understory vegetation is present. Shoot photosynthesis and environmental parameters were measured simultaneously. Despite significant variations in climatic conditions and shoot photosynthetic rates in non-girdled trees, no diurnal patterns in soil respiration rates and (delta) 13 C were noted in either treatment. The lack of detectable diurnal changes in both treatments indicates that modeling of daily boreal forest carbon balances based on single instantaneous measurements are unlikely to be misconstrued by substantial diurnal trends. However, it was suggested that spatial variable should be accounted for, given the large standard errors. The impact of tree girdling on soil respiration rates also emphasized the significance of canopy photosynthesis in driving soil processes. 37 refs., 2 figs

  14. A Medical Cloud-Based Platform for Respiration Rate Measurement and Hierarchical Classification of Breath Disorders

    Directory of Open Access Journals (Sweden)

    Atena Roshan Fekr

    2014-06-01

    Full Text Available The measurement of human respiratory signals is crucial in cyberbiological systems. A disordered breathing pattern can be the first symptom of different physiological, mechanical, or psychological dysfunctions. Therefore, a real-time monitoring of the respiration patterns, as well as respiration rate is a critical need in medical applications. There are several methods for respiration rate measurement. However, despite their accuracy, these methods are expensive and could not be integrated in a body sensor network. In this work, we present a real-time cloud-based platform for both monitoring the respiration rate and breath pattern classification, remotely. The proposed system is designed particularly for patients with breathing problems (e.g., respiratory complications after surgery or sleep disorders. Our system includes calibrated accelerometer sensor, Bluetooth Low Energy (BLE and cloud-computing model. We also suggest a procedure to improve the accuracy of respiration rate for patients at rest positions. The overall error in the respiration rate calculation is obtained 0.53% considering SPR-BTA spirometer as the reference. Five types of respiration disorders, Bradapnea, Tachypnea, Cheyn-stokes, Kaussmal, and Biot’s breathing are classified based on hierarchical Support Vector Machine (SVM with seven different features. We have evaluated the performance of the proposed classification while it is individualized to every subject (case 1 as well as considering all subjects (case 2. Since the selection of kernel function is a key factor to decide SVM’s performance, in this paper three different kernel functions are evaluated. The experiments are conducted with 11 subjects and the average accuracy of 94.52% for case 1 and the accuracy of 81.29% for case 2 are achieved based on Radial Basis Function (RBF. Finally, a performance evaluation has been done for normal and impaired subjects considering sensitivity, specificity and G-mean parameters

  15. Separating the effect of respiration from the heart rate variability for cases of constant harmonic breathing

    Directory of Open Access Journals (Sweden)

    Kircher Michael

    2015-09-01

    Full Text Available Heart Rate Variability studies are a known measure for the autonomous control of the heart rate. In special situations, its interpretation can be ambiguous, since the respiration has a major influence on the heart rate variability. For this reason it has often been proposed to measure Heart Rate Variability, while the subjects are breathing at a constant respiration rate. That way the spectral influence of the respiration is known. In this work we propose to remove this constant respiratory influence from the heart rate and the Heart Rate Variability parameters to gain respiration free autonomous controlled heart rate signal. The spectral respiratory component in the heart rate signal is detected and characterized. Subsequently the respiratory effect on Heart Rate Variability is removed using spectral filtering approaches, such as the Notch filter or the Raised Cosine filter. As a result new decoupled Heart Variability parameters are gained, which could lead to new additional interpretations of the autonomous control of the heart rate.

  16. Estimate of respiration rate and physicochemical changes of fresh-cut apples stored under different temperatures

    Directory of Open Access Journals (Sweden)

    Cristiane Fagundes

    2013-03-01

    Full Text Available In this study, the influence of storage temperature and passive modified packaging (PMP on the respiration rate and physicochemical properties of fresh-cut Gala apples (Malus domestica B. was investigated. The samples were packed in flexible multilayer bags and stored at 2 °C, 5 °C, and 7 °C for eleven days. Respiration rate as a function of CO2 and O2 concentrations was determined using gas chromatography. The inhibition parameters were estimated using a mathematical model based on Michaelis-Menten equation. The following physicochemical properties were evaluated: total soluble solids, pH, titratable acidity, and reducing sugars. At 2 °C, the maximum respiration rate was observed after 150 hours. At 5 °C and 7 °C the maximum respiration rates were observed after 100 and 50 hours of storage, respectively. The inhibition model results obtained showed a clear effect of CO2 on O2 consumption. The soluble solids decreased, although not significantly, during storage at the three temperatures studied. Reducing sugars and titratable acidity decreased during storage and the pH increased. These results indicate that the respiration rate influenced the physicochemical properties.

  17. Relationship between oxygen concentration, respiration and filtration rate in blue mussel Mytilus edulis

    Science.gov (United States)

    Tang, Baojun; Riisgård, Hans Ulrik

    2018-03-01

    The large water-pumping and particle-capturing gills of the filter-feeding blue mussel Mytilus edulis are oversized for respiratory purposes. Consequently, the oxygen uptake rate of the mussel has been suggested to be rather insensitive to decreasing oxygen concentrations in the ambient water, since the diffusion rate of oxygen from water flowing through the mussel determines oxygen uptake. We tested this hypothesis by measuring the oxygen uptake in mussels exposed to various oxygen concentrations. These concentrations were established via N2-bubbling of the water in a respiration chamber with mussels fed algal cells to stimulate fully opening of the valves. It was found that mussels exposed to oxygen concentrations decreasing from 9 to 2 mg O2/L resulted in a slow but significant reduction in the respiration rate, while the filtration rate remained high and constant. Thus, a decrease of oxygen concentration by 78% only resulted in a 25% decrease in respiration rate. However, at oxygen concentrations below 2 mg O2/L M. edulis responded by gradually closing its valves, resulting in a rapid decrease of filtration rate, concurrent with a rapid reduction of respiration rate. These observations indicated that M. edulis is no longer able to maintain its normal aerobic metabolism at oxygen concentration below 2 mg O2/L, and there seems to be an energy-saving mechanism in bivalve molluscs to strongly reduce their activity when exposed to low oxygen conditions.

  18. The effects of operational conditions on the respiration rate of Tubificidae.

    Directory of Open Access Journals (Sweden)

    Juqing Lou

    Full Text Available Tubificidae is often used in the wastewater treatment systems to minimize the sludge production because it can be fed on the activated sludge. The process conditions have effect on the growth, reproduction, and sludge reduction efficiency of Tubificidae. The effects of the water quality, density of worms, pH, temperature and dissolved oxygen (DO concentration on the respiration rate of Tubificidae were investigated to determine the optimal conditions for the growth and metabolism of the worms and reveal the mechanisms involving the efficient sludge reduction in terms of these conditions. It was observed that the respiration rate was highest in the water discharged from an ecosystem that included symbiotic Tubificidae and microbes and was lowest in distilled water. Considering density of the worms, the highest rate was 81.72±5.12 mg O2/g(dry weight·h·L with 0.25 g (wet weight of worms in 1 L test flask. The maximum Tubificidae respiration rate was observed at a pH of 8.0±0.05, a rate that was more than twice as high as those observed at other pH values. The respiration rate increased in the temperature range of ∼8°C-22°C, whereas the rate declined in the temperature range of ∼22°C-30°C. The respiration rate of Tubificidae was very high for DO range of ∼3.5-4.5 mg/L, and the rates were relatively low for out of this DO range. The results of this study revealed the process conditions which influenced the growth, and reproduction of Tubificidae and sludge reduction at a microscopic level, which could be a theoretical basis for the cultivation and application of Tubificidae in wastewater treatment plants.

  19. A combined electrochemical and optical trapping platform for measuring single cell respiration rates at electrode interfaces

    International Nuclear Information System (INIS)

    Gross, Benjamin J.; El-Naggar, Mohamed Y.

    2015-01-01

    Metal-reducing bacteria gain energy by extracellular electron transfer to external solids, such as naturally abundant minerals, which substitute for oxygen or the other common soluble electron acceptors of respiration. This process is one of the earliest forms of respiration on earth and has significant environmental and technological implications. By performing electron transfer to electrodes instead of minerals, these microbes can be used as biocatalysts for conversion of diverse chemical fuels to electricity. Understanding such a complex biotic-abiotic interaction necessitates the development of tools capable of probing extracellular electron transfer down to the level of single cells. Here, we describe an experimental platform for single cell respiration measurements. The design integrates an infrared optical trap, perfusion chamber, and lithographically fabricated electrochemical chips containing potentiostatically controlled transparent indium tin oxide microelectrodes. Individual bacteria are manipulated using the optical trap and placed on the microelectrodes, which are biased at a suitable oxidizing potential in the absence of any chemical electron acceptor. The potentiostat is used to detect the respiration current correlated with cell-electrode contact. We demonstrate the system with single cell measurements of the dissimilatory-metal reducing bacterium Shewanella oneidensis MR-1, which resulted in respiration currents ranging from 15 fA to 100 fA per cell under our measurement conditions. Mutants lacking the outer-membrane cytochromes necessary for extracellular respiration did not result in any measurable current output upon contact. In addition to the application for extracellular electron transfer studies, the ability to electronically measure cell-specific respiration rates may provide answers for a variety of fundamental microbial physiology questions

  20. A combined electrochemical and optical trapping platform for measuring single cell respiration rates at electrode interfaces.

    Science.gov (United States)

    Gross, Benjamin J; El-Naggar, Mohamed Y

    2015-06-01

    Metal-reducing bacteria gain energy by extracellular electron transfer to external solids, such as naturally abundant minerals, which substitute for oxygen or the other common soluble electron acceptors of respiration. This process is one of the earliest forms of respiration on earth and has significant environmental and technological implications. By performing electron transfer to electrodes instead of minerals, these microbes can be used as biocatalysts for conversion of diverse chemical fuels to electricity. Understanding such a complex biotic-abiotic interaction necessitates the development of tools capable of probing extracellular electron transfer down to the level of single cells. Here, we describe an experimental platform for single cell respiration measurements. The design integrates an infrared optical trap, perfusion chamber, and lithographically fabricated electrochemical chips containing potentiostatically controlled transparent indium tin oxide microelectrodes. Individual bacteria are manipulated using the optical trap and placed on the microelectrodes, which are biased at a suitable oxidizing potential in the absence of any chemical electron acceptor. The potentiostat is used to detect the respiration current correlated with cell-electrode contact. We demonstrate the system with single cell measurements of the dissimilatory-metal reducing bacterium Shewanella oneidensis MR-1, which resulted in respiration currents ranging from 15 fA to 100 fA per cell under our measurement conditions. Mutants lacking the outer-membrane cytochromes necessary for extracellular respiration did not result in any measurable current output upon contact. In addition to the application for extracellular electron transfer studies, the ability to electronically measure cell-specific respiration rates may provide answers for a variety of fundamental microbial physiology questions.

  1. A combined electrochemical and optical trapping platform for measuring single cell respiration rates at electrode interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Benjamin J. [Department of Physics and Astronomy, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089-0484 (United States); El-Naggar, Mohamed Y., E-mail: mnaggar@usc.edu [Department of Physics and Astronomy, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089-0484 (United States); Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-0484 (United States); Department of Chemistry, University of Southern California, Los Angeles, California 90089-0484 (United States)

    2015-06-15

    Metal-reducing bacteria gain energy by extracellular electron transfer to external solids, such as naturally abundant minerals, which substitute for oxygen or the other common soluble electron acceptors of respiration. This process is one of the earliest forms of respiration on earth and has significant environmental and technological implications. By performing electron transfer to electrodes instead of minerals, these microbes can be used as biocatalysts for conversion of diverse chemical fuels to electricity. Understanding such a complex biotic-abiotic interaction necessitates the development of tools capable of probing extracellular electron transfer down to the level of single cells. Here, we describe an experimental platform for single cell respiration measurements. The design integrates an infrared optical trap, perfusion chamber, and lithographically fabricated electrochemical chips containing potentiostatically controlled transparent indium tin oxide microelectrodes. Individual bacteria are manipulated using the optical trap and placed on the microelectrodes, which are biased at a suitable oxidizing potential in the absence of any chemical electron acceptor. The potentiostat is used to detect the respiration current correlated with cell-electrode contact. We demonstrate the system with single cell measurements of the dissimilatory-metal reducing bacterium Shewanella oneidensis MR-1, which resulted in respiration currents ranging from 15 fA to 100 fA per cell under our measurement conditions. Mutants lacking the outer-membrane cytochromes necessary for extracellular respiration did not result in any measurable current output upon contact. In addition to the application for extracellular electron transfer studies, the ability to electronically measure cell-specific respiration rates may provide answers for a variety of fundamental microbial physiology questions.

  2. Analyses of Heart Rate, Respiration and Cardiorespiratory Coupling in Patients with Schizophrenia

    Directory of Open Access Journals (Sweden)

    Steffen Schulz

    2015-01-01

    Full Text Available Schizophrenia is a severe mental disorder associated with a significantly increased cardiovascular mortality rate. However, the underlying mechanisms leading to this cardiovascular disease (CVD are not fully known. Therefore, the objective of this study was to characterize the cardiorespiratory influence by investigating heart rate, respiration and the causal strength and direction of cardiorespiratory coupling (CRC, based mainly on entropy measures. We investigated 23 non-medicated patients with schizophrenia (SZ, comparing them to 23 age- and gender-matched healthy controls (CO. A significantly reduced complexity was found for the heart rate and a significantly increased complexity in respiration and CRC in SZ patients when compared to corresponding measurements from CO (p < 0.001. CRC analyses revealed a clear coupling, with a driver-responder relationship from respiration to heart rate in SZ patients. Moreover, a slight driver-responder relationship from heart rate to respiration could be recognized. These findings lead to the assumption that SZ should be considered to be a high-risk group for CVD. We hypothesize that the varying cardiorespiratory regulation contributes to the increased risk for cardiac mortality. Therefore, regular monitoring of the cardiorespiratory status of SZ is suggested to identify autonomic regulation impairment at an early stage—to develop timely and effective treatment and intervention strategies.

  3. Higher assimilation than respiration sensitivity to drought for a desert ecosystem in Central Asia.

    Science.gov (United States)

    Gu, Daxing; Otieno, Dennis; Huang, Yuqing; Wang, Quan

    2017-12-31

    Responses of ecosystem assimilation and respiration to global climate change vary considerably among terrestrial ecosystems constrained by both biotic and abiotic factors. In this study, net CO 2 exchange between ecosystem and atmosphere (NEE) was measured over a 4-year period (2013-2016) using eddy covariance technology in a desert ecosystem in Central Asia. Ecosystem assimilation (gross primary production, GPP) and respiration (R eco ) were derived from NEE by fitting light response curves to NEE data based on day- and nighttime data, and their responses to soil water content (SWC) and evaporative fraction (EF) were assessed during the growing season. Results indicated that both GPP and R eco linearly decreased with declining SWC, with the sensitivity of GPP to SWC being 3.8 times higher than that of R eco during the entire growing season. As a result, ecosystem CO 2 sequestration capacity decreased from 4.00μmolm -2 s -1 to 1.00μmolm -2 s -1 , with increasing soil drought . On a seasonal scale, significant correlation between GPP and SWC was only found in spring while that between R eco and SWC was found in all growing seasons with the sensitivity increasing steadily from spring to autumn. EF had a low correlation with SWC, GPP and R eco (R 2 =0.03, 0.02, 0.05, respectively), indicating that EF was not a good proxy for soil drought and energy partitioning was not tightly coupled to ecosystem carbon exchanges in this desert ecosystem. The study deepens our knowledge of ecosystem carbon exchange and its response to drought as well as its coupling with ecosystem energy partitioning in an extreme dry desert. The information is critical for better assessing carbon sequestration capacity in dryland, and for understanding its feedback to climate change. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Monitoring biodegradation of diesel fuel in bioventing processes using in situ respiration rate.

    Science.gov (United States)

    Lee, T H; Byun, I G; Kim, Y O; Hwang, I S; Park, T J

    2006-01-01

    An in situ measuring system of respiration rate was applied for monitoring biodegradation of diesel fuel in a bioventing process for bioremediation of diesel contaminated soil. Two laboratory-scale soil columns were packed with 5 kg of soil that was artificially contaminated by diesel fuel as final TPH (total petroleum hydrocarbon) concentration of 8,000 mg/kg soil. Nutrient was added to make a relative concentration of C:N:P = 100:10:1. One soil column was operated with continuous venting mode, and the other one with intermittent (6 h venting/6 h rest) venting mode. On-line O2 and CO2 gas measuring system was applied to measure O2 utilisation and CO2 production during biodegradation of diesel for 5 months. Biodegradation rate of TPH was calculated from respiration rate measured by the on-line gas measuring system. There were no apparent differences between calculated biodegradation rates from two columns with different venting modes. The variation of biodegradation rates corresponded well with trend of the remaining TPH concentrations comparing other biodegradation indicators, such as C17/pristane and C18/phytane ratio, dehydrogenase activity, and the ratio of hydrocarbon utilising bacteria to total heterotrophic bacteria. These results suggested that the on-line measuring system of respiration rate would be applied to monitoring biodegradation rate and to determine the potential applicability of bioventing process for bioremediation of oil contaminated soil.

  5. Respiration rate detection based on intensity modulation using plastic optical fiber

    Science.gov (United States)

    Anwar, Zawawi Mohd; Ziran Nurul Sufia, Nor; Hadi, Manap

    2017-11-01

    This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  6. Respiration rate detection based on intensity modulation using plastic optical fiber

    Directory of Open Access Journals (Sweden)

    Mohd Anwar Zawawi

    2017-01-01

    Full Text Available This paper presents the implementation of respiration rate measurement via a simple intensity-based optical fiber sensor using optical fiber technology. The breathing rate is measured based on the light intensity variation due to the longitudinal gap changes between two separated fibers. In order to monitor the breathing rate continuously, the output from the photodetector conditioning circuit is connected to a low-cost Arduino kit. At the sensing point, two optical fiber cables are positioned in series with a small gap and fitted inside a transparent plastic tube. To ensure smooth movement of the fiber during inhale and exhale processes as well as to maintain the gap of the fiber during idle condition, the fiber is attached firmly to a stretchable bandage. This study shows that this simple fiber arrangement can be applied to detect respiration activity which might be critical for patient monitoring.

  7. Ocean-scale patterns in community respiration rates along continuous transects across the Pacific Ocean.

    Science.gov (United States)

    Wilson, Jesse M; Severson, Rodney; Beman, J Michael

    2014-01-01

    Community respiration (CR) of organic material to carbon dioxide plays a fundamental role in ecosystems and ocean biogeochemical cycles, as it dictates the amount of production available to higher trophic levels and for export to the deep ocean. Yet how CR varies across large oceanographic gradients is not well-known: CR is measured infrequently and cannot be easily sensed from space. We used continuous oxygen measurements collected by autonomous gliders to quantify surface CR rates across the Pacific Ocean. CR rates were calculated from changes in apparent oxygen utilization and six different estimates of oxygen flux based on wind speed. CR showed substantial spatial variation: rates were lowest in ocean gyres (mean of 6.93 mmol m(-3) d(-1)±8.0 mmol m(-3) d(-1) standard deviation in the North Pacific Subtropical Gyre) and were more rapid and more variable near the equator (8.69 mmol m(-3) d(-1)±7.32 mmol m(-3) d(-1) between 10°N and 10°S) and near shore (e.g., 5.62 mmol m(-3) d(-1)±45.6 mmol m(-3) d(-1) between the coast of California and 124°W, and 17.0 mmol m(-3) d(-1)±13.9 mmol m(-3) d(-1) between 156°E and the Australian coast). We examined how CR varied with coincident measurements of temperature, turbidity, and chlorophyll concentrations (a proxy for phytoplankton biomass), and found that CR was weakly related to different explanatory variables across the Pacific, but more strongly related to particular variables in different biogeographical areas. Our results indicate that CR is not a simple linear function of chlorophyll or temperature, and that at the scale of the Pacific, the coupling between primary production, ocean warming, and CR is complex and variable. We suggest that this stems from substantial spatial variation in CR captured by high-resolution autonomous measurements.

  8. Relative rates of nitric oxide and nitrous oxide production by nitrifiers, denitrifiers, and nitrate respirers

    Science.gov (United States)

    Anderson, I. C.; Levine, J. S.

    1986-01-01

    An account is given of the atmospheric chemical and photochemical effects of biogenic nitric and nitrous oxide emissions. The magnitude of the biogenic emission of NO is noted to remain uncertain. Possible soil sources of NO and N2O encompass nitrification by autotropic and heterotropic nitrifiers, denitrification by nitrifiers and denitrifiers, nitrate respiration by fermenters, and chemodenitrification. Oxygen availability is the primary determinant of these organisms' relative rates of activity. The characteristics of this major influence are presently investigated in light of the effect of oxygen partial pressure on NO and N2O production by a wide variety of common soil-nitrifying, denitrifying, and nitrate-respiring bacteria under laboratory conditions. The results obtained indicate that aerobic soils are primary sources only when there is sufficient moisture to furnish anaerobic microsites for denitrification.

  9. Effect of the Storage Temperature, Duration and Gamma Irradiation on the Respiration Rate and Sugar Content of Minituber 'Superior'

    International Nuclear Information System (INIS)

    Lim, J.H.; Hwangbo, J.K.; Baek, M.H.; Kim, J.H.; Kim, J.S.; Lee, M.C.

    2005-01-01

    This study was to evaluate whether ionizing gamma radiation could be applied to break the dormancy of a potato minituber. The respiration rate of the minitubers was significantly affected by the storage temperature and a low dose gamma radiation. Ionizing radiation of 8 Gy enhanced the respiration rate of the potato tuber stored at 10°C for 20 days. The potato tuber subjected to 4 and 8 Gy after 40 days storage at 10 and 10°C exhibited higher respiration rates compared to the control (non-irradiated), but not at st. However, the ionizing radiation did not exhibit on significant effect on the respiration rate of the potato tuber stored for 60 days. It was observed that minitubers stored for 20 days had significant response to the storage temperature in terms of the total sugar content the higher the storage temperature, the lower the total sugar content. It was measured that the reducing sugar content was increased under the storage conditions both 5 and 10°C for 40 days, but not to 20°C. The total sugar contents in the minituber stored for 60 days were similar to those stored for 40 days. The data was discussed on the relationships among the storage duration, temperature and ionizing radiation. (author)

  10. Ocean-scale patterns in community respiration rates along continuous transects across the Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Jesse M Wilson

    Full Text Available Community respiration (CR of organic material to carbon dioxide plays a fundamental role in ecosystems and ocean biogeochemical cycles, as it dictates the amount of production available to higher trophic levels and for export to the deep ocean. Yet how CR varies across large oceanographic gradients is not well-known: CR is measured infrequently and cannot be easily sensed from space. We used continuous oxygen measurements collected by autonomous gliders to quantify surface CR rates across the Pacific Ocean. CR rates were calculated from changes in apparent oxygen utilization and six different estimates of oxygen flux based on wind speed. CR showed substantial spatial variation: rates were lowest in ocean gyres (mean of 6.93 mmol m(-3 d(-1±8.0 mmol m(-3 d(-1 standard deviation in the North Pacific Subtropical Gyre and were more rapid and more variable near the equator (8.69 mmol m(-3 d(-1±7.32 mmol m(-3 d(-1 between 10°N and 10°S and near shore (e.g., 5.62 mmol m(-3 d(-1±45.6 mmol m(-3 d(-1 between the coast of California and 124°W, and 17.0 mmol m(-3 d(-1±13.9 mmol m(-3 d(-1 between 156°E and the Australian coast. We examined how CR varied with coincident measurements of temperature, turbidity, and chlorophyll concentrations (a proxy for phytoplankton biomass, and found that CR was weakly related to different explanatory variables across the Pacific, but more strongly related to particular variables in different biogeographical areas. Our results indicate that CR is not a simple linear function of chlorophyll or temperature, and that at the scale of the Pacific, the coupling between primary production, ocean warming, and CR is complex and variable. We suggest that this stems from substantial spatial variation in CR captured by high-resolution autonomous measurements.

  11. Effect of thermal treatment on the body temperature, respiration and pulse rate in dogs chronically irradiated with γ-rays

    International Nuclear Information System (INIS)

    Popova, N.A.; Petrovnin, M.G.

    1975-01-01

    Male dogs were chronically gamma-irradiated at different dose rates (0.06, 0.17, 0.34 rad/day) and subjected to heat treatment (raising of temperature from 22 0 C to 40 0 C) during winter and summer. Internal (rectal) temperature, respiration rate and heart rate were recorded. The respiration rate changed appreciably in all groups during all periods of temperature rise and fall in the chamber, but the variations were more pronounced in all groups during the winter experiment than during the summer experiment; no significant differences were found between the groups of animals while the respiration rate was changing, either in the winter or in the summer experiment. In both experiments, there were considerable heart rate variations only in the control group and in the group exposed to a dose rate of 0.06 rad/day. (V.A.P.)

  12. Does cypermethrin affect enzyme activity, respiration rate and walking behavior of the maize weevil (Sitophilus zeamais)?

    Institute of Scientific and Technical Information of China (English)

    Ronnie Von Santos Veloso; Eliseu José G.Pereira; Raul Narciso C.Guedes; Maria Goreti A.Oliveira

    2013-01-01

    Insecticides cause a range of sub-lethal effects on targeted insects,which are frequently detrimental to them.However,targeted insects are able to cope with insecticides within sub-lethal ranges,which vary with their susceptibility.Here we assessed the response of three strains of the maize weevil Sitophilus zeamais Motschulsky (Coleoptera:Curculionidae) to sub-lethal exposure to the pyrethoid insecticide cypermethrin.We expected enzyme induction associated with cypermethrin resistance since it would aid the resistant insects in surviving such exposure.Lower respiration rate and lower activity were also expected in insecticide-resistant insects since these traits are also likely to favor survivorship under insecticide exposure.Curiously though,cypermethrin did not affect activity of digestive and energy metabolism enzymes,and even reduced the activity of some enzymes (particularly for cellulase and cysteine-proteinase activity in this case).There was strain variation in response,which may be (partially) related to insecticide resistance in some strains.Sub-lethal exposure to cypermethrin depressed proteolytic and mainly cellulolytic activity in the exposed insects,which is likely to impair their fitness.However,such exposure did not affect respiration rate and walking behavior of the insects (except for the susceptible strain where walking activity was reduced).Walking activity varies with strain and may minimize insecticide exposure,which should be a concern,particularly if associated with (physiological) insecticide resistance.

  13. A regulated response to impaired respiration slows behavioral rates and increases lifespan in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    David Cristina

    2009-04-01

    Full Text Available When mitochondrial respiration or ubiquinone production is inhibited in Caenorhabditis elegans, behavioral rates are slowed and lifespan is extended. Here, we show that these perturbations increase the expression of cell-protective and metabolic genes and the abundance of mitochondrial DNA. This response is similar to the response triggered by inhibiting respiration in yeast and mammalian cells, termed the "retrograde response". As in yeast, genes switched on in C. elegans mitochondrial mutants extend lifespan, suggesting an underlying evolutionary conservation of mechanism. Inhibition of fstr-1, a potential signaling gene that is up-regulated in clk-1 (ubiquinone-defective mutants, and its close homolog fstr-2 prevents the expression of many retrograde-response genes and accelerates clk-1 behavioral and aging rates. Thus, clk-1 mutants live in "slow motion" because of a fstr-1/2-dependent pathway that responds to ubiquinone. Loss of fstr-1/2 does not suppress the phenotypes of all long-lived mitochondrial mutants. Thus, although different mitochondrial perturbations activate similar transcriptional and physiological responses, they do so in different ways.

  14. Forest floor and mineral soil respiration rates in a northern Minnesota red pine chronosequence

    Science.gov (United States)

    Powers, Matthew; Kolka, Randall; Bradford, John B.; Palik, Brian J.; Jurgensen, Martin

    2018-01-01

    We measured total soil CO2 efflux (RS) and efflux from the forest floor layers (RFF) in red pine (Pinus resinosaAit.) stands of different ages to examine relationships between stand age and belowground C cycling. Soil temperature and RS were often lower in a 31-year-old stand (Y31) than in 9-year-old (Y9), 61-year-old (Y61), or 123-year-old (Y123) stands. This pattern was most apparent during warm summer months, but there were no consistent differences in RFF among different-aged stands. RFF represented an average of 4–13% of total soil respiration, and forest floor removal increased moisture content in the mineral soil. We found no evidence of an age effect on the temperature sensitivity of RS, but respiration rates in Y61 and Y123 were less sensitive to low soil moisture than RS in Y9 and Y31. Our results suggest that soil respiration’s sensitivity to soil moisture may change more over the course of stand development than its sensitivity to soil temperature in red pine, and that management activities that alter landscape-scale age distributions in red pine forests could have significant impacts on rates of soil CO2 efflux from this forest type.

  15. Stress level in wild harbour porpoises (Phocoena phocoena) during satellite tagging measured by respiration, heart rate and cortisol

    DEFF Research Database (Denmark)

    Eskesen, Ida Grønborg; Teilmann, J.; Geertsen, B. M.

    2009-01-01

    During satellite tagging of harbour porpoises (Phocoena phocoena), heart rate, respiration rate and cortisol value were measured to evaluate stress effects during handling and tagging. Respiration rates were obtained using video recordings, heart rates were recorded and serum cortisol levels were...... between cortisol and month of year, sex and body length. As high individual variations occurred in response to tagging of harbour porpoises, it is not possible to give general advice based oil the factors investigated, on how to reduce stress during handling. However, pouring water over the animal...

  16. Ballast minerals and the sinking carbon flux in the ocean: carbon-specific respiration rates and sinking velocity of marine snow aggregates

    Directory of Open Access Journals (Sweden)

    M. H. Iversen

    2010-09-01

    Full Text Available Recent observations have shown that fluxes of ballast minerals (calcium carbonate, opal, and lithogenic material and organic carbon fluxes are closely correlated in the bathypelagic zones of the ocean. Hence it has been hypothesized that incorporation of biogenic minerals within marine aggregates could either protect the organic matter from decomposition and/or increase the sinking velocity via ballasting of the aggregates. Here we present the first combined data on size, sinking velocity, carbon-specific respiration rate, and composition measured directly in three aggregate types; Emiliania huxleyi aggregates (carbonate ballasted, Skeletonema costatum aggregates (opal ballasted, and aggregates made from a mix of both E. huxleyi and S. costatum (carbonate and opal ballasted. Overall average carbon-specific respiration rate was ~0.13 d−1 and did not vary with aggregate type and size. Ballasting from carbonate resulted in 2- to 2.5-fold higher sinking velocities than those of aggregates ballasted by opal. We compiled literature data on carbon-specific respiration rate and sinking velocity measured in aggregates of different composition and sources. Compiled carbon-specific respiration rates (including this study vary between 0.08 d−1 and 0.20 d−1. Sinking velocity increases with increasing aggregate size within homogeneous sources of aggregates. When compared across different particle and aggregate sources, however, sinking velocity appeared to be independent of particle or aggregate size. The carbon-specific respiration rate per meter settled varied between 0.0002 m−1 and 0.0030 m−1, and decreased with increasing aggregate size. It was lower for calcite ballasted aggregates as compared to that of similar sized opal ballasted aggregates.

  17. A method of detection of respiration rate on Android using UWB Impulse Radar

    Directory of Open Access Journals (Sweden)

    Young-Jin Park

    2016-12-01

    Full Text Available Monitoring respiration rate is important because it can help to detect and prevent abnormal respiratory rates that can lead to cardiac arrest and chronic obstructive pulmonary disease. Nowadays, most medical measurement and monitoring devices are either invasive or wired but people are hesitant to attach physiological sensors to their body. In this study, we investigated whether real-time medical measurement of breathing using Novelda’s Ultra-Wideband Impulse Radio (IR-UWB–which does not need to be attached to the human body and is also non-invasive–is possible on Android. Experimental results obtained were found to be comparable to those of a commercial healthcare device.

  18. The effect of food on the respiration rates of Daphnia magna using a flow-through system

    Directory of Open Access Journals (Sweden)

    Claire Schmoker

    2003-09-01

    Full Text Available Respiration rates and gut fluorescence of the cladoceran Daphnia magna were studied using a flow-through system. This open system has the advantage of introducing food or producing a starvation effect during the course of the experiment. Severe variations in respiratory rates were observed in relation to the presence or absence of food, indicating short-term variability. Organisms kept starved or at low food for a long period (15-20 h responded to a sudden increase in food by increasing their respiration rates three- to four-fold in parallel with their gut content. A significant relationship between gut fluorescence and respiration rates was observed, suggesting that feeding and the related swimming activity were responsible for the observed metabolic variability.

  19. Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.

    Directory of Open Access Journals (Sweden)

    Kimmo Kalevi Kahilainen

    Full Text Available Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L. morphs (two pelagic, one littoral and one profundal using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one profundal recently diverged via adaptive radiation to exploit different major niches in a deep and thermally stratified subarctic lake. We found evidence that the morphs used different thermal niches. The profundal morph had the most distinct thermal niche and consistently occupied the coldest thermal habitat of the lake, whereas differences were less pronounced among the shallow water pelagic and littoral morphs. Our results indicated ontogenetic shifts in thermal niches: juveniles of all whitefish morphs inhabited warmer ambient temperatures than adults. According to sampling of the otolith nucleus, hatching temperatures were higher for benthic compared to pelagic morphs. Estimated respiration rate was the lowest for benthivorous profundal morph, contrasting with the higher values estimated for the other morphs that inhabited shallower and warmer water. These preliminary results suggest that physiological adaptation to different thermal habitats shown by the sympatric morphs may play a significant role in maintaining or strengthening niche segregation and divergence in life-history traits, potentially contributing to reproductive isolation and incipient speciation.

  20. Spectral analysis of time series of events: effect of respiration on heart rate in neonates

    International Nuclear Information System (INIS)

    Van Drongelen, Wim; Williams, Amber L; Lasky, Robert E

    2009-01-01

    Certain types of biomedical processes such as the heart rate generator can be considered as signals that are sampled by the occurring events, i.e. QRS complexes. This sampling property generates problems for the evaluation of spectral parameters of such signals. First, the irregular occurrence of heart beats creates an unevenly sampled data set which must either be pre-processed (e.g. by using trace binning or interpolation) prior to spectral analysis, or analyzed with specialized methods (e.g. Lomb's algorithm). Second, the average occurrence of events determines the Nyquist limit for the sampled time series. Here we evaluate different types of spectral analysis of recordings of neonatal heart rate. Coupling between respiration and heart rate and the detection of heart rate itself are emphasized. We examine both standard and data adaptive frequency bands of heart rate signals generated by models of coupled oscillators and recorded data sets from neonates. We find that an important spectral artifact occurs due to a mirror effect around the Nyquist limit of half the average heart rate. Further we conclude that the presence of respiratory coupling can only be detected under low noise conditions and if a data-adaptive respiratory band is used

  1. Variation in foliar respiration and wood CO2 efflux rates among species and canopy layers in a wet tropical forest.

    Science.gov (United States)

    Asao, Shinichi; Bedoya-Arrieta, Ricardo; Ryan, Michael G

    2015-02-01

    As tropical forests respond to environmental change, autotrophic respiration may consume a greater proportion of carbon fixed in photosynthesis at the expense of growth, potentially turning the forests into a carbon source. Predicting such a response requires that we measure and place autotrophic respiration in a complete carbon budget, but extrapolating measurements of autotrophic respiration from chambers to ecosystem remains a challenge. High plant species diversity and complex canopy structure may cause respiration rates to vary and measurements that do not account for this complexity may introduce bias in extrapolation more detrimental than uncertainty. Using experimental plantations of four native tree species with two canopy layers, we examined whether species and canopy layers vary in foliar respiration and wood CO2 efflux and whether the variation relates to commonly used scalars of mass, nitrogen (N), photosynthetic capacity and wood size. Foliar respiration rate varied threefold between canopy layers, ∼0.74 μmol m(-2) s(-1) in the overstory and ∼0.25 μmol m(-2) s(-1) in the understory, but little among species. Leaf mass per area, N and photosynthetic capacity explained some of the variation, but height explained more. Chamber measurements of foliar respiration thus can be extrapolated to the canopy with rates and leaf area specific to each canopy layer or height class. If area-based rates are sampled across canopy layers, the area-based rate may be regressed against leaf mass per area to derive the slope (per mass rate) to extrapolate to the canopy using the total leaf mass. Wood CO2 efflux varied 1.0-1.6 μmol m(-2) s(-1) for overstory trees and 0.6-0.9 μmol m(-2) s(-1) for understory species. The variation in wood CO2 efflux rate was mostly related to wood size, and little to species, canopy layer or height. Mean wood CO2 efflux rate per surface area, derived by regressing CO2 efflux per mass against the ratio of surface

  2. Bacterial Respiration and Growth Rates Affect the Feeding Preferences, Brood Size and Lifespan of Caenorhabditis elegans

    Science.gov (United States)

    Yu, Li; Yan, Xiaomei; Ye, Chenglong; Zhao, Haiyan; Chen, Xiaoyun; Hu, Feng; Li, Huixin

    2015-01-01

    Bacteria serve as live food and nutrients for bacterial-feeding nematodes (BFNs) in soils, and influence nematodes behavior and physiology through their metabolism. Five bacterial taxa (Bacillus amyloliquefaciens JX1, Variovorax sp. JX14, Bacillus megaterium JX15, Pseudomonas fluorescens Y1 and Escherichia coli OP50) and the typical BFN Caenorhabditis elegans were selected to study the effects of bacterial respiration and growth rates on the feeding preferences, brood size and lifespan of nematodes. P. fluorescens Y1 and E. coli OP50 were found to be more active, with high respiration and rapid growth, whereas B. amyloliquefaciens JX1 and B. megaterium JX15 were inactive. The nematode C. elegans preferred active P. fluorescens Y1 and E. coli OP50 obviously. Furthermore, worms that fed on these two active bacteria produced more offspring but had shorter lifespan, while inactive and less preferred bacteria had increased nematodes lifespan and decreased the brood size. Based on these results, we propose that the bacterial activity may influence the behavior and life traits of C. elegans in the following ways: (1) active bacteria reproduce rapidly and emit high levels of CO2 attracting C. elegans; (2) these active bacteria use more resources in the nematodes’ gut to sustain their survival and reproduction, thereby reducing the worm's lifespan; (3) inactive bacteria may provide less food for worms than active bacteria, thus increasing nematodes lifespan but decreasing their fertility. Nematodes generally require a balance between their preferred foods and beneficial foods, only preferred food may not be beneficial for nematodes. PMID:26222828

  3. Non-contact acquisition of respiration and heart rates using Doppler radar with time domain peak-detection algorithm.

    Science.gov (United States)

    Xiaofeng Yang; Guanghao Sun; Ishibashi, Koichiro

    2017-07-01

    The non-contact measurement of the respiration rate (RR) and heart rate (HR) using a Doppler radar has attracted more attention in the field of home healthcare monitoring, due to the extremely low burden on patients, unconsciousness and unconstraint. Most of the previous studies have performed the frequency-domain analysis of radar signals to detect the respiration and heartbeat frequency. However, these procedures required long period time (approximately 30 s) windows to obtain a high-resolution spectrum. In this study, we propose a time-domain peak detection algorithm for the fast acquisition of the RR and HR within a breathing cycle (approximately 5 s), including inhalation and exhalation. Signal pre-processing using an analog band-pass filter (BPF) that extracts respiration and heartbeat signals was performed. Thereafter, the HR and RR were calculated using a peak position detection method, which was carried out via LABVIEW. To evaluate the measurement accuracy, we measured the HR and RR of seven subjects in the laboratory. As a reference of HR and RR, the persons wore contact sensors i.e., an electrocardiograph (ECG) and a respiration band. The time domain peak-detection algorithm, based on the Doppler radar, exhibited a significant correlation coefficient of HR of 0.92 and a correlation coefficient of RR of 0.99, between the ECG and respiration band, respectively.

  4. Non-Invasive Detection of Respiration and Heart Rate with a Vehicle Seat Sensor.

    Science.gov (United States)

    Wusk, Grace; Gabler, Hampton

    2018-05-08

    This study demonstrates the feasibility of using a seat sensor designed for occupant classification from a production passenger vehicle to measure an occupant’s respiration rate (RR) and heart rate (HR) in a laboratory setting. Relaying occupant vital signs after a crash could improve emergency response by adding a direct measure of the occupant state to an Advanced Automatic Collision Notification (AACN) system. Data was collected from eleven participants with body weights ranging from 42 to 91 kg using a Ford Mustang passenger seat and seat sensor. Using a ballistocardiography (BCG) approach, the data was processed by time domain filtering and frequency domain analysis using the fast Fourier transform to yield RR and HR in a 1-min sliding window. Resting rates over the 30-min data collection and continuous RR and HR signals were compared to laboratory physiological instruments using the Bland-Altman approach. Differences between the seat sensor and reference sensor were within 5 breaths per minute for resting RR and within 15 beats per minute for resting HR. The time series comparisons for RR and HR were promising with the frequency analysis technique outperforming the peak detection technique. However, future work is necessary for more accurate and reliable real-time monitoring of RR and HR outside the laboratory setting.

  5. Relationships between root respiration rate and root morphology, chemistry and anatomy in Larix gmelinii and Fraxinus mandshurica.

    Science.gov (United States)

    Jia, Shuxia; McLaughlin, Neil B; Gu, Jiacun; Li, Xingpeng; Wang, Zhengquan

    2013-06-01

    Tree roots are highly heterogeneous in form and function. Previous studies revealed that fine root respiration was related to root morphology, tissue nitrogen (N) concentration and temperature, and varied with both soil depth and season. The underlying mechanisms governing the relationship between root respiration and root morphology, chemistry and anatomy along the root branch order have not been addressed. Here, we examined these relationships of the first- to fifth-order roots for near surface roots (0-10 cm) of 22-year-old larch (Larix gmelinii L.) and ash (Fraxinus mandshurica L.) plantations. Root respiration rate at 18 °C was measured by gas phase O2 electrodes across the first five branching order roots (the distal roots numbered as first order) at three times of the year. Root parameters of root diameter, specific root length (SRL), tissue N concentration, total non-structural carbohydrates (starch and soluble sugar) concentration (TNC), cortical thickness and stele diameter were also measured concurrently. With increasing root order, root diameter, TNC and the ratio of root TNC to tissue N concentration increased, while the SRL, tissue N concentration and cortical proportion decreased. Root respiration rate also monotonically decreased with increasing root order in both species. Cortical tissue (including exodermis, cortical parenchyma and endodermis) was present in the first three order roots, and cross sections of the cortex for the first-order root accounted for 68% (larch) and 86% (ash) of the total cross section of the root. Root respiration was closely related to root traits such as diameter, SRL, tissue N concentration, root TNC : tissue N ratio and stele-to-root diameter proportion among the first five orders, which explained up to 81-94% of variation in the rate of root respiration for larch and up to 83-93% for ash. These results suggest that the systematic variations of root respiration rate within tree fine root system are possibly due to the

  6. Macromolecular Rate Theory (MMRT) Provides a Thermodynamics Rationale to Underpin the Convergent Temperature Response in Plant Leaf Respiration

    Science.gov (United States)

    Liang, L. L.; Arcus, V. L.; Heskel, M.; O'Sullivan, O. S.; Weerasinghe, L. K.; Creek, D.; Egerton, J. J. G.; Tjoelker, M. G.; Atkin, O. K.; Schipper, L. A.

    2017-12-01

    Temperature is a crucial factor in determining the rates of ecosystem processes such as leaf respiration (R) - the flux of plant respired carbon dioxide (CO2) from leaves to the atmosphere. Generally, respiration rate increases exponentially with temperature as modelled by the Arrhenius equation, but a recent study (Heskel et al., 2016) showed a universally convergent temperature response of R using an empirical exponential/polynomial model whereby the exponent in the Arrhenius model is replaced by a quadratic function of temperature. The exponential/polynomial model has been used elsewhere to describe shoot respiration and plant respiration. What are the principles that underlie these empirical observations? Here, we demonstrate that macromolecular rate theory (MMRT), based on transition state theory for chemical kinetics, is equivalent to the exponential/polynomial model. We re-analyse the data from Heskel et al. 2016 using MMRT to show this equivalence and thus, provide an explanation based on thermodynamics, for the convergent temperature response of R. Using statistical tools, we also show the equivalent explanatory power of MMRT when compared to the exponential/polynomial model and the superiority of both of these models over the Arrhenius function. Three meaningful parameters emerge from MMRT analysis: the temperature at which the rate of respiration is maximum (the so called optimum temperature, Topt), the temperature at which the respiration rate is most sensitive to changes in temperature (the inflection temperature, Tinf) and the overall curvature of the log(rate) versus temperature plot (the so called change in heat capacity for the system, ). The latter term originates from the change in heat capacity between an enzyme-substrate complex and an enzyme transition state complex in enzyme-catalysed metabolic reactions. From MMRT, we find the average Topt and Tinf of R are 67.0±1.2 °C and 41.4±0.7 °C across global sites. The average curvature (average

  7. Can we relate respiration rates of bark and wood with tissue nitrogen concentrations and branch-level CO2 fluxes across woody species?

    Science.gov (United States)

    Eller, A. S.; Wright, I.; Cernusak, L. A.

    2013-12-01

    Respiration from above-ground woody tissue is generally responsible for 5-15% of ecosystem respiration (~ 30% of total above-ground respiration). The CO2 respired by branches comes from both the sapwood and the living layers within the bark, but because there is considerable movement of respired CO2 within woody tissues (e.g. in the transpiration stream), and because the bark can present a considerable barrier to CO2 diffusion, it can be difficult to interpret measured CO2 efflux from intact branches in relation to the respiration rates of the component tissues, and to relative mass allocation to each. In this study we investigated these issues in 15 evergreen tree and shrub species native to the Sydney area in eastern Australia. We measured CO2 efflux and light-dependent refixation of respired CO2 in photosynthetic bark from the exterior surfaces of branches (0.5-1.5 cm in diameter), and measured the tissue-specific respiration rates of the bark and wood from those same branches. We also measured the nitrogen content and tissue density of the wood and bark to determine: 1) Among species, what is the relationship between %N and tissue respiration? 2) How is photosynthetic refixation of CO2 related to respiration and %N in the bark and underlying wood? and 3) What is the relationship between branch CO2 efflux and the respiration rates of the underlying wood and bark that make up the branch? Across the 15 species %N was a better predictor of respiration in wood than in bark. CO2 efflux measured from the exterior of the stem in the dark was positively correlated with photosynthetic refixation and explained ~40% of the variation in rates of refixation. Refixation rates were not strongly related to bark or wood %N. Differences among species in CO2 efflux rates were not well explained by differences in bark or wood %N and there was a stronger relationship between bark respiration and CO2 efflux than between wood respiration and CO2 efflux. These results suggest that the

  8. Influence of cell detachment on the respiration rate of tumor and endothelial cells.

    Science.gov (United States)

    Danhier, Pierre; Copetti, Tamara; De Preter, Géraldine; Leveque, Philippe; Feron, Olivier; Jordan, Bénédicte F; Sonveaux, Pierre; Gallez, Bernard

    2013-01-01

    Cell detachment is a procedure routinely performed in cell culture and a necessary step in many biochemical assays including the determination of oxygen consumption rates (OCR) in vitro. In vivo, cell detachment has been shown to exert profound metabolic influences notably in cancer but also in other pathologies, such as retinal detachment for example. In the present study, we developed and validated a new technique combining electron paramagnetic resonance (EPR) oximetry and the use of cytodex 1 and collagen-coated cytodex 3 dextran microbeads, which allowed the unprecedented comparison of the OCR of adherent and detached cells with high sensitivity. Hence, we demonstrated that both B16F10 melanoma cells and human umbilical vein endothelial cells (HUVEC) experience strong OCR decrease upon trypsin or collagenase treatments. The reduction of cell oxygen consumption was more pronounced with a trypsin compared to a collagenase treatment. Cells remaining in suspension also encounter a marked intracellular ATP depletion and an increase in the lactate production/glucose uptake ratio. These findings highlight the important influence exerted by cell adhesion/detachment on cell respiration, which can be probed with the unprecedented experimental assay that was developed and validated in this study.

  9. Influence of Cell Detachment on the Respiration Rate of Tumor and Endothelial Cells

    Science.gov (United States)

    Danhier, Pierre; Copetti, Tamara; De Preter, Géraldine; Leveque, Philippe; Feron, Olivier; Jordan, Bénédicte F.; Sonveaux, Pierre; Gallez, Bernard

    2013-01-01

    Cell detachment is a procedure routinely performed in cell culture and a necessary step in many biochemical assays including the determination of oxygen consumption rates (OCR) in vitro. In vivo, cell detachment has been shown to exert profound metabolic influences notably in cancer but also in other pathologies, such as retinal detachment for example. In the present study, we developed and validated a new technique combining electron paramagnetic resonance (EPR) oximetry and the use of cytodex 1 and collagen-coated cytodex 3 dextran microbeads, which allowed the unprecedented comparison of the OCR of adherent and detached cells with high sensitivity. Hence, we demonstrated that both B16F10 melanoma cells and human umbilical vein endothelial cells (HUVEC) experience strong OCR decrease upon trypsin or collagenase treatments. The reduction of cell oxygen consumption was more pronounced with a trypsin compared to a collagenase treatment. Cells remaining in suspension also encounter a marked intracellular ATP depletion and an increase in the lactate production/glucose uptake ratio. These findings highlight the important influence exerted by cell adhesion/detachment on cell respiration, which can be probed with the unprecedented experimental assay that was developed and validated in this study. PMID:23382841

  10. Insights Gained from the Dehalococcoides ethenogenes Strain 195’s Transcriptome Responding to a Wide Range of Respiration Rates and Substrate Types

    Science.gov (United States)

    2012-04-01

    fermented yeast , pure hydrogen, or endogenous biomass decay). When similarly respiring (~120 ?eeq PCE/(L-hr)) batch and PSS cultures were contrasted, the...REPORT Insights gained from the “Dehalococcoides ethenogenes” strain 195?s transcriptome responding to a wide range of respiration rates and substrate...types. 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Bacteria of the group “Dehalococcoides” display the ability to respire recalcitrant chlorinated

  11. Temperature sensitivity of soil respiration rates enhanced by microbial community response.

    Science.gov (United States)

    Karhu, Kristiina; Auffret, Marc D; Dungait, Jennifer A J; Hopkins, David W; Prosser, James I; Singh, Brajesh K; Subke, Jens-Arne; Wookey, Philip A; Agren, Göran I; Sebastià, Maria-Teresa; Gouriveau, Fabrice; Bergkvist, Göran; Meir, Patrick; Nottingham, Andrew T; Salinas, Norma; Hartley, Iain P

    2014-09-04

    Soils store about four times as much carbon as plant biomass, and soil microbial respiration releases about 60 petagrams of carbon per year to the atmosphere as carbon dioxide. Short-term experiments have shown that soil microbial respiration increases exponentially with temperature. This information has been incorporated into soil carbon and Earth-system models, which suggest that warming-induced increases in carbon dioxide release from soils represent an important positive feedback loop that could influence twenty-first-century climate change. The magnitude of this feedback remains uncertain, however, not least because the response of soil microbial communities to changing temperatures has the potential to either decrease or increase warming-induced carbon losses substantially. Here we collect soils from different ecosystems along a climate gradient from the Arctic to the Amazon and investigate how microbial community-level responses control the temperature sensitivity of soil respiration. We find that the microbial community-level response more often enhances than reduces the mid- to long-term (90 days) temperature sensitivity of respiration. Furthermore, the strongest enhancing responses were observed in soils with high carbon-to-nitrogen ratios and in soils from cold climatic regions. After 90 days, microbial community responses increased the temperature sensitivity of respiration in high-latitude soils by a factor of 1.4 compared to the instantaneous temperature response. This suggests that the substantial carbon stores in Arctic and boreal soils could be more vulnerable to climate warming than currently predicted.

  12. Salicylic Acid Regulation of Respiration in Higher Plants: Alternative Oxidase Expression.

    Science.gov (United States)

    Rhoads, DM; McIntosh, L

    1992-01-01

    Alternative respiratory pathway capacity increases during the development of the thermogenic appendix of a voodoo lily inflorescence. The levels of the alternative oxidase proteins increased dramatically between D-4 (4 days prior to the day of anthesis) and D-3 and continued to increase until the day of anthesis (D-day). The level of salicylic acid (SA) in the appendix is very low early on D-1, but increases to a high level in the evening of D-1. Thermogenesis occurs after a few hours of light on D-day. Therefore, the initial accumulation of the alternative oxidase proteins precedes the increase in SA by 3 days, indicating that other regulators may be involved. A 1.6-kb transcript encoding the alternative oxidase precursor protein accumulated to a high level in the appendix tissue by D-1. Application of SA to immature appendix tissue caused an increase in alternative pathway capacity and a dramatic accumulation of the alternative oxidase proteins and the 1.6-kb transcript. Time course experiments showed that the increase in capacity, protein levels, and transcript level corresponded precisely. The response to SA was blocked by cycloheximide or actinomycin D, indicating that de novo transcription and translation are required. However, nuclear, in vitro transcription assays indicated that the accumulation of the 1.6-kb transcript did not result from a simple increase in the rate of transcription of aox1. PMID:12297672

  13. Relict Mountain Permafrost Area (Loess Plateau, China) Exhibits High Ecosystem Respiration Rates and Accelerating Rates in Response to Warming

    Science.gov (United States)

    Mu, Cuicui; Wu, Xiaodong; Zhao, Qian; Smoak, Joseph M.; Yang, Yulong; Hu, Lian; Zhong, Wen; Liu, Guimin; Xu, Haiyan; Zhang, Tingjun

    2017-10-01

    Relict permafrost regions are characterized by thin permafrost and relatively high temperatures. Understanding the ecosystem respiration rate (ERR) and its relationship with soil hydrothermal conditions in these areas can provide knowledge regarding the permafrost carbon cycle in a warming world. In this study, we examined a permafrost area, a boundary area, and a seasonally frozen ground area within a relict permafrost region on the east edge of the Qinghai-Tibetan Plateau, China. Measurements from July 2015 to September 2016 showed that the mean annual ecosystem CO2 emissions for the boundary area were greater than the permafrost area. The Q10 value of the ERRs in the seasonally frozen ground area was greater than the permafrost area, indicating that the carbon emissions in the nonpermafrost areas were more sensitive to warming. The 1 year open-top chamber (OTC) warming increased soil temperatures in both the permafrost and seasonally frozen ground areas throughout the year, and the warming increased the ERRs by 1.18 (0.99-1.38, with interquartile range) and 1.13 (0.75-1.54, with interquartile range) μmol CO2 m-2 s-1 in permafrost and seasonally frozen ground areas, respectively. The OTC warming increased annual ERRs by approximately 50% for both permafrost and seasonally frozen ground areas with half the increase occurring during the nongrowing seasons. These results suggest that the ERRs in relict permafrost are high in comparison with arctic regions, and the carbon balance in relict permafrost areas could be greatly changed by climate warming.

  14. Monitoring oral temperature, heart rate, and respiration rate of West Indian manatees (Trichechus manatus) during capture and handling in the field

    Science.gov (United States)

    Wong, Arthur W.; Bonde, Robert K.; Siegal-Willott, Jessica; Stamper, M. Andrew; Colee, James; Powell, James A.; Reid, James P.; Deutsch, Charles J.; Harr, Kendal E.

    2012-01-01

    West Indian manatees (Trichechus manatus) are captured, handled, and transported to facilitate conservation, research, and rehabilitation efforts. Monitoring manatee oral temperature (OT), heart rate (HR), and respiration rate (RR) during out-of-water handling can assist efforts to maintain animal well-being and improve medical response to evidence of declining health. To determine effects of capture on manatee vital signs, we monitored OT, HR, and RR continuously for a 50-min period in 38 healthy, awake, juvenile and adult Florida manatees (T. m. latirostris) and 48 similar Antillean manatees (T. m. manatus). We examined creatine kinase (CK), potassium (K+), serum amyloid A (SAA), and lactate values for each animal to assess possible systemic inflammation and muscular trauma. OT range was 29.5 to 36.2° C, HR range was 32 to 88 beats/min, and RR range was 0 to 17 breaths/5 min. Antillean manatees had higher initial OT, HR, and RR than Florida manatees (p capture and handling in the field or in a captive care setting.

  15. A pilot study of the nocturnal respiration rates in COPD patients in the home environment using a non-contact biomotion sensor

    International Nuclear Information System (INIS)

    Ballal, Tarig; Zaffaroni, Alberto; Heneghan, Conor; Shouldice, Redmond; Boyle, Patricia; McNicholas, Walter T; De Chazal, Philip; Donnelly, Seamas C

    2014-01-01

    Nocturnal respiration rate parameters were collected from 20 COPD subjects over an 8 week period, to determine if changes in respiration rate were associated with exacerbations of COPD. These subjects were primarily GOLD Class 2 to 4, and had been recently discharged from hospital following a recent exacerbation. The respiration rates were collected using a non-contact radio-frequency biomotion sensor which senses respiratory effort and body movement using a short-range radio-frequency sensor. An adaptive notch filter was applied to the measured signal to determine respiratory rate over rolling 15 s segments. The accuracy of the algorithm was initially verified using ten manually-scored 15 min segments of respiration extracted from overnight polysomnograms. The calculated respiration rates were within 1 breath min −1 for >98% of the estimates. For the 20 subjects monitored, 11 experienced one or more subsequent exacerbation of COPD (ECOPD) events during the 8 week monitoring period (19 events total). Analysis of the data revealed a significant increase in nocturnal respiration rate (e.g. >2 breath min −1 ) prior to many ECOPD events. Using a simple classifier of a change of 1 breath min −1 in the mode of the nocturnal respiration rate, a predictive rule showed a sensitivity of 63% and specificity of 85% for predicting an exacerbation within a 5 d window. We conclude that it is possible to collect respiration rates reliably in the home environment, and that the respiration rate may be a potential indicator of change in clinical status. (paper)

  16. Rates of Litter Decomposition and Soil Respiration in Relation to Soil Temperature and Water in Different-Aged Pinus massoniana Forests in the Three Gorges Reservoir Area, China

    Science.gov (United States)

    Zeng, Lixiong; Huang, Zhilin; Lei, Jingpin; Zhou, Benzhi; Li, Maihe

    2014-01-01

    To better understand the soil carbon dynamics and cycling in terrestrial ecosystems in response to environmental changes, we studied soil respiration, litter decomposition, and their relations to soil temperature and soil water content for 18-months (Aug. 2010–Jan. 2012) in three different-aged Pinus massoniana forests in the Three Gorges Reservoir Area, China. Across the experimental period, the mean total soil respiration and litter respiration were 1.94 and 0.81, 2.00 and 0.60, 2.19 and 0.71 µmol CO2 m−2 s−1, and the litter dry mass remaining was 57.6%, 56.2% and 61.3% in the 20-, 30-, and 46-year-old forests, respectively. We found that the temporal variations of soil respiration and litter decomposition rates can be well explained by soil temperature at 5 cm depth. Both the total soil respiration and litter respiration were significantly positively correlated with the litter decomposition rates. The mean contribution of the litter respiration to the total soil respiration was 31.0%–45.9% for the three different-aged forests. The present study found that the total soil respiration was not significantly affected by forest age when P. masonniana stands exceed a certain age (e.g. >20 years old), but it increased significantly with increased soil temperature. Hence, forest management strategies need to protect the understory vegetation to limit soil warming, in order to reduce the CO2 emission under the currently rapid global warming. The contribution of litter decomposition to the total soil respiration varies across spatial and temporal scales. This indicates the need for separate consideration of soil and litter respiration when assessing the climate impacts on forest carbon cycling. PMID:25004164

  17. Taxa de respiração de cenouras minimamente processadas e armazenadas em diferentes temperaturas Respiration rate of storage processed carrots at different temperatures

    Directory of Open Access Journals (Sweden)

    Wigberto Antonio Spagnol

    2006-09-01

    Full Text Available Entre as hortaliças minimamente processadas, a cenoura é uma das mais populares, sendo comercializada de várias maneiras: raladas, cortadas em fatias, palitos, e ainda apresentadas na forma de mini-cenoura (baby carrot. O objetivo deste estudo foi determinar as taxas respiratórias de cenouras (Daucus carota da cultivar Nantes minimamente processadas. O armazenamento foi realizado nas temperaturas de 1 °C, 5 °C e 11 °C, e 90% UR. A taxa respiratória foi determinada usando um fluxo contínuo de ar. O teor de CO2 e etileno foi medido por um cromatógrafo a gás. A taxa de respiração para as cenouras fatiadas foi mais alta do que para os produtos inteiros. Os valores da energia de ativação obtidos para as cenouras fatiadas e inteiras foi de 69,82 kJmol-1 e 54,60 kJmol-1, respectivamente. A produção de etileno foi insignificante para as cenouras durante os 14 dias de armazenamento.The carrot is one of the most popular vegetables from minimally processed vegetables. It is commercialized in many different ways: shreds, slices, sticks and baby carrots. The aim of this work is to determine the respiration rate of minimally processed carrots. They were in storage at temperatures of 1 °C, 5 °C and 11 °C, and 90% RH. The respiration rate was determined using continuous humidification airflow and measuring the CO2 concentration using a gas chromatograph connected to a microcomputer. The respiration rates of the minimally processed carrots showed a higher respiration rate than for the whole products. The activation energy values calculated for the minimally processed carrots corresponded to 69.82 kJmol-1 for the whole products. The ethylene production for the carrots remained insignificant throughout the 14 days of storage.

  18. Effects of minimal processing on the respiration rate and quality of rambutan cv. ‘Rong-Rien’

    Directory of Open Access Journals (Sweden)

    Buncha Ooraikul

    2008-04-01

    Full Text Available Respiration rate at 4oC and minimal processing of rambutan cv. ‘Rong-Rien’ were investigated. Rambutan was harvested from Amphur Ban Na San, Surat Thani Province, at the stage when its skin was turning into a combination of red, green and yellow. After harvesting, the fruits were size-graded to 27-30 fruits/kg, hydrocooled to 14oC, packed with ice in Styrofoam boxes and transported to the laboratory at Prince of Songkla University within 6 h. The respiration rate of fresh rambutan fruits was monitored. For minimal processing, the fruits were soaked in warm solution (55oC of 100 ppm sodium hypochlorite for one min and immediately cooled in cold water until their internal temperature reached 14oC. The minimal process included peeling, with and without coring. The peeled and peeled and cored rambutan samples were immersed in a solution of 0.5% citric acid + 0.5% CaCl2 at 4oC for 2 min. The average respiration rates (within 6 h at 4oC of whole fruit, peeled, and peeled and cored rambutan samples were measured and found to be 122, 134 and 143 mg CO2/kg/h, respectively. These findings indicated that a preparation style as peeled rambutan without coring, nylon/LLDPE bag, storage temperature of 4.0±1oC, were suitably applied for processed rambutans. To obtain a longer extended shelf life (>12 days of minimally processed peeled rambutans, further study on food additives, including acidulants and preservative used and gas composition in modified atmosphere packaging (MAP is needed.

  19. Dependence of wheat and rice respiration on tissue nitrogen and the corresponding net carbon fixation efficiency under different rates of nitrogen application

    Science.gov (United States)

    Sun, Wenjuan; Huang, Yao; Chen, Shutao; Zou, Jianwen; Zheng, Xunhua

    2007-02-01

    To quantitatively address the role of tissue N in crop respiration under various agricultural practices, and to consequently evaluate the impact of synthetic fertilizer N application on biomass production and respiration, and hence net carbon fixation efficiency ( E ncf), pot and field experiments were carried out for an annual rotation of a rice-wheat cropping system from 2001 to 2003. The treatments of the pot experiments included fertilizer N application, sowing date and planting density. Different rates of N application were tested in the field experiments. Static opaque chambers were used for sampling the gas. The respiration as CO2 emission was detected by a gas chromatograph. A successive biomass clipping method was employed to determine the crop autotrophic respiration coefficient ( R a). Results from the pot experiments revealed a linear relationship between R a and tissue N content as R a = 4.74N-1.45 ( R 2 = 0.85, P < 0.001). Measurements and calculations from the field experiments indicated that fertilizer N application promoted not only biomass production but also increased the respiration of crops. A further investigation showed that the increase of carbon loss in terms of respiration owing to fertilizer N application exceeded that of net carbon gain in terms of aboveground biomass when fertilizer N was applied over a certain rate. Consequently, the E ncf declined as the N application rate increased.

  20. [Temperature sensitivity of wheat plant respiration and soil respiration influenced by increased UV-B radiation from elongation to flowering periods].

    Science.gov (United States)

    Chen, Shu-Tao; Hu, Zheng-Hua; Li, Han-Mao; Ji, Yu-Hong; Yang, Yan-Ping

    2009-05-15

    Field experiment was carried out in the spring of 2008 in order to investigate the effects of increased UV-B radiation on the temperature sensitivity of wheat plant respiration and soil respiration from elongation to flowering periods. Static chamber-gas chromatography method was used to measure ecosystem respiration and soil respiration under 20% UV-B radiation increase and control. Environmental factors such as temperature and moisture were also measured. Results indicated that supplemental UV-B radiation inhibited the ecosystem respiration and soil respiration from wheat elongation to flowering periods, and the inhibition effect was more obvious for soil respiration than for ecosystem respiration. Ecosystem respiration rates, on daily average, were 9%, 9%, 3%, 16% and 30% higher for control than for UV-B treatment forthe five measurement days, while soil respiration rates were 99%, 93%, 106%, 38% and 10% higher for control than for UV-B treatment. The Q10s (temperature sensitivity coefficients) for plant respiration under control and UV-B treatments were 1.79 and 1.59, respectively, while the Q10s for soil respiration were 1.38 and 1.76, respectively. The Q10s for ecosystem respiration were 1.65 and 1.63 under CK and UV-B treatments, respectively. Supplemental UV-B radiation caused a lower Q10 for plant respiration and a higher Q10 for soil respiration, although no significant effect of supplemental UV-B radiation on the Q10 for ecosystem respiration was found.

  1. Toward the definition of a carbon budget model: seasonal variation and temperature effect on respiration rate of vegetative and reproductive organs of pistachio trees (Pistacia vera).

    Science.gov (United States)

    Marra, Francesco P; Barone, Ettore; La Mantia, Michele; Caruso, Tiziano

    2009-09-01

    This study, as a preliminary step toward the definition of a carbon budget model for pistachio trees (Pistacia vera L.), aimed at estimating and evaluating the dynamics of respiration of vegetative and reproductive organs of pistachio tree. Trials were performed in 2005 in a commercial orchard located in Sicily (370 m a.s.l.) on five bearing 20-year-old pistachio trees of cv. Bianca grafted onto Pistachio terebinthus L. Growth analyses and respiration measurements were done on vegetative (leaf) and reproductive (infructescence) organs during the entire growing season (April-September) at biweekly intervals. Results suggested that the respiration rates of pistachio reproductive and vegetative organs were related to their developmental stage. Both for leaf and for infructescence, the highest values were observed during the earlier stages of growth corresponding to the phases of most intense organ growth. The sensitivity of respiration activity to temperature changes, measured by Q(10), showed an increase throughout the transition from immature to mature leaves, as well as during fruit development. The data collected were also used to estimate the seasonal carbon loss by respiration activity for a single leaf and a single infructescence. The amount of carbon lost by respiration was affected by short-term temperature patterns, organ developmental stage and tissue function.

  2. Predawn respiration rates during flowering are highly predictive of yield response in Gossypium hirsutum when yield variability is water-induced

    Science.gov (United States)

    Respiratory carbon evolution by leaves under abiotic stress is implicated as a major limitation to crop productivity; however, respiration rates of fully expanded leaves are positively associated with plant growth rates. Given the substantial sensitivity of plant growth to drought, it was hypothesiz...

  3. Rich or poor: Who should pay higher tax rates?

    Science.gov (United States)

    Murilo Castro de Oliveira, Paulo

    2017-08-01

    A dynamic agent model is introduced with an annual random wealth multiplicative process followed by taxes paid according to a linear wealth-dependent tax rate. If poor agents pay higher tax rates than rich agents, eventually all wealth becomes concentrated in the hands of a single agent. By contrast, if poor agents are subject to lower tax rates, the economic collective process continues forever.

  4. respiration and transpiration characteristics of selected fresh fruits

    African Journals Online (AJOL)

    AISA

    were higher in optimal atmospheres. The Q10 values ... High respiration rates increase tissue aging and decrease the ability of the product to repel ... Two types of containers were used for the ..... availability of oxygen around the product also.

  5. Gaseous elemental mercury emissions and CO2 respiration rates in terrestrial soils under controlled aerobic and anaerobic laboratory conditions

    International Nuclear Information System (INIS)

    Obrist, Daniel; Fain, Xavier; Berger, Carsen

    2010-01-01

    Mercury (Hg) levels in terrestrial soils are linked to the presence of organic carbon (C). Carbon pools are highly dynamic and subject to mineralization processes, but little is known about the fate of Hg during decomposition. This study evaluated relationships between gaseous Hg emissions from soils and carbon dioxide (CO 2 ) respiration under controlled laboratory conditions to assess potential losses of Hg to the atmosphere during C mineralization. Results showed a linear correlation (r 2 = 0.49) between Hg and CO 2 emissions in 41 soil samples, an effect unlikely to be caused by temperature, radiation, different Hg contents, or soil moisture. Stoichiometric comparisons of Hg/C ratios of emissions and underlying soil substrates suggest that 3% of soil Hg was subject to evasion. Even minute emissions of Hg upon mineralization, however, may be important on a global scale given the large Hg pools sequestered in terrestrial soils and C stocks. We induced changes in CO 2 respiration rates and observed Hg flux responses, including inducement of anaerobic conditions by changing chamber air supply from N 2 /O 2 (80% and 20%, respectively) to pure N 2 . Unexpectedly, Hg emissions almost quadrupled after O 2 deprivation while oxidative mineralization (i.e., CO 2 emissions) was greatly reduced. This Hg flux response to anaerobic conditions was lacking when repeated with sterilized soils, possibly due to involvement of microbial reduction of Hg 2+ by anaerobes or indirect abiotic effects such as alterations in soil redox conditions. This study provides experimental evidence that Hg volatilization, and possibly Hg 2+ reduction, is related to O 2 availability in soils from two Sierra Nevada forests. If this result is confirmed in soils from other areas, the implication is that Hg volatilization from terrestrial soils is partially controlled by soil aeration and that low soil O 2 levels and possibly low soil redox potentials lead to increased Hg volatilization from soils.

  6. Respirator Filter Efficiency Testing Against Particulate and Biological Aerosols Under Moderate to High Flow Rates

    Science.gov (United States)

    2006-08-01

    flow rate through the test filter. The flow rate was measured using a mass flow meter (Series 4000, TSI, Shoreview, MN). Several modifications were made...operating conditions. This included assessing the effect of non- isokinetic sampling, flow calibrations, and characterization of the challenge...sampling bias on the measured penetrations due to the non- isokinetic sampling downstream. 3.3.2.2 System Characterization. Shakedown tests were

  7. Determination of respiration rates in water with sub-micromolar oxygen concentrations

    Directory of Open Access Journals (Sweden)

    Emilio Garcia-Robledo

    2016-11-01

    Full Text Available It is crucial for our study and understanding of element transformations in low-oxygen waters that we are able to reproduce the in situ conditions during laboratory incubations to an extent that does not result in unacceptable artefacts. In this study we have explored how experimental conditions affect measured rates of O2 consumption in low-O2 waters from the anoxic basin of Golfo Dulce (Costa Rica and oceanic waters off Chile-Peru. High-sensitivity optode dots placed within all-glass incubation containers allowed for high resolution O2 concentration measurements in the nanomolar and low µmolar range and thus also for the determination of rates of oxygen consumption by microbial communities. Consumption rates increased dramatically (from 3 and up to 60 times by prolonged incubations, and started to increase after 4-5 hours in surface waters and after 10-15 h in water from below the upper mixed layer. Estimated maximum growth rates during the incubations suggest the growth of opportunistic microorganism with doubling times as low as 2.8 and 4.6 h for the coastal waters of Golfo Dulce (Costa Rica and oceanic waters off Chile and Peru, respectively. Deoxygenation by inert gas bubbling led to increases in subsequently determined rates, possibly by liberation of organics from lysis of sensitive organisms, particle or aggregate alterations or other processes mediated by the strong turbulence. Stirring of the water during the incubation led to an about 50% increase in samples previously deoxygenated by bubbling, but had no effect in untreated samples. Our data indicate that data for microbial activity obtained by short incubations of minimally manipulated water are most reliable, but deoxygenation is a prerequisite for many laboratory experiments, such as determination of denitrification rates, as O2 contamination by sampling is practically impossible to avoid.

  8. Evaluating a new method to estimate the rate of leaf respiration in the light by analysis of combined gas exchange and chlorophyll fluorescence measurements

    NARCIS (Netherlands)

    Yin, X.; Sun, Z.; Struik, P.C.; Gu, J.

    2011-01-01

    Day respiration (R(d)) is an important parameter in leaf ecophysiology. It is difficult to measure directly and is indirectly estimated from gas exchange (GE) measurements of the net photosynthetic rate (A), commonly using the Laisk method or the Kok method. Recently a new method was proposed to

  9. Ecosystem function in oil sands wetlands : rates of detrital decomposition, moss growth, and microbial respiration in oilsands wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Wytrykush, C. [Windsor Univ., ON (Canada); Hornung, J. [Petro-Canada, Calgary, AB (Canada)

    2007-07-01

    A study was conducted in which leaf litter breakdown and biomass accrual in 31 reference and oilsands affected (OSPM) wetlands in Northeastern Alberta was examined. The purpose was to determine how the decomposition of dead plant matter controls the primary productivity in wetlands. The data collected from this study will provide information about carbon flow and dynamics in oilsands affected wetlands. The study involved the investigation of wetlands that contrasted in water origin (OSPM vs. reference), sediment origin (OSPM vs. natural), sediment organic content and age. Mesh bags containing 5 g of dried Typha (cattail) or 20 g of damp moss were placed into 31 wetlands in order to monitor the rate at which biomass was lost to decomposition, as measured by changes in dry mass. After 1 year, moss growth was found to be greatest in younger wetlands with natural sediments. Cattail decomposition was found to be slower in wetlands containing OSPM water than that in reference wetlands. Preliminary analysis of respiration rates of biota associated with decomposing cattail indicate that the amount of oxygen consumed is not affected by wetland water source, sediment source, level of initial sediment organic content, or age.

  10. Estimating diversification rates for higher taxa: BAMM can give problematic estimates of rates and rate shifts.

    Science.gov (United States)

    Meyer, Andreas L S; Wiens, John J

    2018-01-01

    Estimates of diversification rates are invaluable for many macroevolutionary studies. Recently, an approach called BAMM (Bayesian Analysis of Macro-evolutionary Mixtures) has become widely used for estimating diversification rates and rate shifts. At the same time, several articles have concluded that estimates of net diversification rates from the method-of-moments (MS) estimators are inaccurate. Yet, no studies have compared the ability of these two methods to accurately estimate clade diversification rates. Here, we use simulations to compare their performance. We found that BAMM yielded relatively weak relationships between true and estimated diversification rates. This occurred because BAMM underestimated the number of rates shifts across each tree, and assigned high rates to small clades with low rates. Errors in both speciation and extinction rates contributed to these errors, showing that using BAMM to estimate only speciation rates is also problematic. In contrast, the MS estimators (particularly using stem group ages), yielded stronger relationships between true and estimated diversification rates, by roughly twofold. Furthermore, the MS approach remained relatively accurate when diversification rates were heterogeneous within clades, despite the widespread assumption that it requires constant rates within clades. Overall, we caution that BAMM may be problematic for estimating diversification rates and rate shifts. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  11. The effect of airflow rates and aeration mode on the respiration activity of four organic wastes: Implications on the composting process.

    Science.gov (United States)

    Mejias, Laura; Komilis, Dimitrios; Gea, Teresa; Sánchez, Antoni

    2017-07-01

    The aim of this study was to assess the effect of the airflow and of the aeration mode on the composting process of non-urban organic wastes that are found in large quantities worldwide, namely: (i) a fresh, non-digested, sewage sludge (FSS), (ii) an anaerobically digested sewage sludge (ADSS), (iii) cow manure (CM) and (iv) pig sludge (PS). This assessment was done using respirometric indices. Two aeration modes were tested, namely: (a) a constant air flowrate set at three different initial fixed airflow rates, and (b) an oxygen uptake rate (OUR)-controlled airflow rate. The four wastes displayed the same behaviour namely a limited biological activity at low aeration, while, beyond a threshold value, the increase of the airflow did not significantly increase the dynamic respiration indices (DRI 1 max , DRI 24 max and AT 4 ). The threshold airflow rate varied among wastes and ranged from 42NL air kg -1 DMh -1 for CM and from 67 to 77NL air kg -1 DMh -1 for FSS, ADSS and PS. Comparing the two aeration modes tested (constant air flow, OUR controlled air flow), no statistically significant differences were calculated between the respiration activity indices obtained at those two aeration modes. The results can be considered representative for urban and non-urban organic wastes and establish a general procedure to measure the respiration activity without limitations by airflow. This will permit other researchers to provide consistent results during the measurement of the respiration activity. Results indicate that high airflows are not required to establish the maximum respiration activity. This can result in energy savings and the prevention of off-gas treatment problems due to the excessive aeration rate in full scale composting plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Respiration rates in forest soil organic horizon materials treated with simulated acid rain

    Energy Technology Data Exchange (ETDEWEB)

    Salonius, P O

    1990-01-01

    The entire organic horizon above the mineral soil was collected under a mature black spruce (Picea mariana) stand in central New Brunswick. The organic horizon consisted of litter, fermentation, and humus layers of 1.5, 4.0, and 1.0 cm depths respectively. In concert with a series of simulated rain experiments, which dealt with the effects of acid precipitation of pH 4.6, 3.6, and 2.6 compared with controls at pH 5.6 on germination and early growth of forest tree seedlings, 30 randomly distributed, unplanted tubes in each rain chamber were exposed to treatment during each of the 5-week treatments of the various tree species. During the experiments, ca 315 mm of simulated rain was deposited on the soil surfaces in the tube containers. Marked decreases in soil microbial activity were found only with pH 2.6 rain, but responsiveness to increasing temperature was lower as rain of greater acidity was applied to the soil. Ammonium nitrogen mineralization rates were not affected by treatment of soil with acidified precipitation. 26 refs., 3 figs., 1 tab.

  13. Respiration in spiders (Araneae).

    Science.gov (United States)

    Schmitz, Anke

    2016-05-01

    Spiders (Araneae) are unique regarding their respiratory system: they are the only animal group that breathe simultaneously with lungs and tracheae. Looking at the physiology of respiration the existence of tracheae plays an important role in spiders with a well-developed tracheal system. Other factors as sex, life time, type of prey capture and the high ability to gain energy anaerobically influence the resting and the active metabolic rate intensely. Most spiders have metabolic rates that are much lower than expected from body mass; but especially those with two pairs of lungs. Males normally have higher resting rates than females; spiders that are less evolved and possess a cribellum have lower metabolic rates than higher evolved species. Freely hunting spiders show a higher energy turnover than spiders hunting with a web. Spiders that live longer than 1 year will have lower metabolic rates than those species that die after 1 year in which development and reproduction must be completed. Lower temperatures and starvation, which most spiders can cope with, will decrease the metabolic rate as well.

  14. A mechanical breathing simulator for respirator test

    International Nuclear Information System (INIS)

    Murata, Mikio; Ikezawa, Yoshio; Yoshida, Yoshikazu

    1976-01-01

    A mechanical breathing simulator has been developed to produce the human respiration for use in respirator test. The respirations were produced through the strokes of piston controlled by a rockerarm with adjustable fulcrum. The respiration rate was governed by motor-speed control, independent of the tidal volume achieved by adjustment of the piston stroke. By the breather, the simulated respirations for work rate 0, 208, 415, 622 and 830 kg-m/min could be produced through the typical dummy head. (auth.)

  15. Higher rates of sex evolve in spatially heterogeneous environments.

    Science.gov (United States)

    Becks, Lutz; Agrawal, Aneil F

    2010-11-04

    The evolution and maintenance of sexual reproduction has puzzled biologists for decades. Although this field is rich in hypotheses, experimental evidence is scarce. Some important experiments have demonstrated differences in evolutionary rates between sexual and asexual populations; other experiments have documented evolutionary changes in phenomena related to genetic mixing, such as recombination and selfing. However, direct experiments of the evolution of sex within populations are extremely rare (but see ref. 12). Here we use the rotifer, Brachionus calyciflorus, which is capable of both sexual and asexual reproduction, to test recent theory predicting that there is more opportunity for sex to evolve in spatially heterogeneous environments. Replicated experimental populations of rotifers were maintained in homogeneous environments, composed of either high- or low-quality food habitats, or in heterogeneous environments that consisted of a mix of the two habitats. For populations maintained in either type of homogeneous environment, the rate of sex evolves rapidly towards zero. In contrast, higher rates of sex evolve in populations experiencing spatially heterogeneous environments. The data indicate that the higher level of sex observed under heterogeneity is not due to sex being less costly or selection against sex being less efficient; rather sex is sufficiently advantageous in heterogeneous environments to overwhelm its inherent costs. Counter to some alternative theories for the evolution of sex, there is no evidence that genetic drift plays any part in the evolution of sex in these populations.

  16. Airborne release fractions/rates and respirable fractions for nonreactor nuclear facilities. Volume 1, Analysis of experimental data

    International Nuclear Information System (INIS)

    1994-12-01

    This handbook contains (1) a systematic compilation of airborne release and respirable fraction experimental data for nonreactor nuclear facilities, (2) assessments of the data, and (3) values derived from assessing the data that may be used in safety analyses when the data are applicable. To assist in consistent and effective use of this information, the handbook provides: identification of a consequence determination methodology in which the information can be used; discussion of the applicability of the information and its general technical limits; identification of specific accident phenomena of interest for which the information is applicable; and examples of use of the consequence determination methodology and airborne release and respirable fraction information

  17. Enabling Higher Data Rates for Planetary Science Missions

    Science.gov (United States)

    Deutsch, L. J.; Townes, S. A.; Lazio, J.; Bell, D. J.; Chahat, N. E.; Kovalik, J. M.; Kuperman, I.; Sauder, J.; Liebrecht, P. E.

    2017-12-01

    The data rate from deep space spacecraft has increased by more than 10 orders of magnitude since the first lunar missions in the 1960s. The demand for increased data rates has stemmed from the increasing sophistication of the science questions being addressed and the concomitant increase in the complexity of the missions themselves (from fly-by to orbit to land and rove). Projections for the next few decades suggest the demand for data rates for deep space missions will continue to increase by approximately one order of magnitude every decade, driven by these same factors. Achieving higher data rates requires a partnership between the spacecraft and the ground system. We describe a series of technology developments for flight telecommunications systems, both at radio frequency (RF) and optical, to enable spacecraft to transmit and receive larger data volumes. These technology developments include deployable high gain antennas for small spacecraft, re-programmable software-defined radios, and optical communication packages designed for CubeSat form factors. The intent is that these developments would provide enhancements in capability for both spacecraft-Earth and spacecraft-spacecraft telecommunications. We also describe the future planning for NASA's Deep Space Network (DSN), which remains the prime conduit for data from all planetary science missions. Through a combination of new antennas and backends being installed over the next five years and incorporation of optical communications, the DSN aims to ensure that the historical improvements in data rates and volumes will continue for many decades. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  18. Estimation of soil respiration rates and soil gas isotopic composition for the different land use of Ultisols from Calhoun CZO.

    Science.gov (United States)

    Cherkinsky, A.; Brecheisen, Z.; Richter, D. D., Jr.; Sheng, H.

    2017-12-01

    CO2 flux from soil is significant in most ecosystems and can account for more than 2/3 of total ecosystem respiration. In many cases CO2 fluxes from soil are estimated using eddy covariance techniques or the classical chamber method with measures of bulk concentrations and isotope composition of CO2. Whereas most of these studies estimate flux from the soil surface, we analyzed its concentration and isotope composition directly in soil profiles down to 8.5m depth. This experiment was conducted in Sumter National Forest in summer of 2016. The samples were collected from 3 different land use history sites: a) reference hardwood stands, mainly of oak and hickory that are taken to be never cultivated; b) cultivated plots, which were also used growing cotton prior to the 1950's but for the last 50 years for growing corn, wheat, legume, sorghum, and sunflowers; c) pine stands, which had been used for growing cotton from beginning of the 19th century and then was abandoned in 1920s and planted with loblolly pine. We have analyzed 3 replicates of each land use. There were measured in the field CO2 and O2 concentration and collected gas samples were analyzed for Δ14C, δ13C and δ18O. CO2 concentration in all types of land use has a maximum about 3m depth, approximately the same depth as the minimum of O2 concentration. Isotope analyses revealed that carbon isotopic composition tend to become lighter with the depth for all three types of land use: in cultivated site it changes from -18%o at 0.5m to -21%o at 5m; in pine site from -22%o to -25%o and in hardwood from-21.5 -24.5%o correspondently, the O2 isotopic composition does not change significantly. Based on analysis of Δ14C the turnover rate of CO2 is getting slower as depth increases. At the first 50 cm the exchange rate is the fastest on cultivated site, likely due to annual tilling, and concentration of 14C is actually equal to atmospheric. However, the turnover rate of Δ14C in soil CO2 slows down significantly as

  19. Effects of simulated warming on soil respiration to XiaoPo lake

    Science.gov (United States)

    Zhao, Shuangkai; Chen, Kelong; Wu, Chengyong; Mao, Yahui

    2018-02-01

    The main flux of carbon cycling in terrestrial and atmospheric ecosystems is soil respiration, and soil respiration is one of the main ways of soil carbon output. This is of great significance to explore the dynamic changes of soil respiration rate and its effect on temperature rise, and the correlation between environmental factors and soil respiration. In this study, we used the open soil carbon flux measurement system (LI-8100, LI-COR, NE) in the experimental area of the XiaoPo Lake wetland in the Qinghai Lake Basin, and the Kobresia (Rs) were measured, and the soil respiration was simulated by simulated temperature (OTC) and natural state. The results showed that the temperature of 5 cm soil was 1.37 °C higher than that of the control during the experiment, and the effect of warming was obvious. The respiration rate of soil under warming and natural conditions showed obvious diurnal variation and monthly variation. The effect of warming on soil respiration rate was promoted and the effect of precipitation on soil respiration rate was inhibited. Further studies have shown that the relationship between soil respiration and 5 cm soil temperature under the control and warming treatments can be described by the exponential equation, and the correlation analysis between the two plots shows a very significant exponential relationship (p main influencing factor of soil respiration in this region.

  20. Reduction Rates for Higher Americium Oxidation States in Nitric Acid

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Travis Shane [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mincher, Bruce Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schmitt, Nicholas C [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-30

    The stability of hexavalent americium was measured using multiple americium concentrations and nitric acid concentrations after contact with the strong oxidant sodium bismuthate. Contrary to our hypotheses Am(VI) was not reduced faster at higher americium concentrations, and the reduction was only zero-order at short time scales. Attempts to model the reduction kinetics using zero order kinetic models showed Am(VI) reduction in nitric acid is more complex than the autoreduction processes reported by others in perchloric acid. The classical zero-order reduction of Am(VI) was found here only for short times on the order of a few hours. We did show that the rate of Am(V) production was less than the rate of Am(VI) reduction, indicating that some Am(VI) undergoes two electron-reduction to Am(IV). We also monitored the Am(VI) reduction in contact with the organic diluent dodecane. A direct comparison of these results with those in the absence of the organic diluent showed the reduction rates for Am(VI) were not statistically different for both systems. Additional americium oxidations conducted in the presence of Ce(IV)/Ce(III) ions showed that Am(VI) is reduced without the typical growth of Am(V) observed in the systems sans Ce ion. This was an interesting result which suggests a potential new reduction/oxidation pathway for Am in the presence of Ce; however, these results were very preliminary, and will require additional experiments to understand the mechanism by which this occurs. Overall, these studies have shown that hexavalent americium is fundamentally stable enough in nitric acid to run a separations process. However, the complicated nature of the reduction pathways based on the system components is far from being rigorously understood.

  1. The activity of ascorbic acid and catechol oxidase, the rate of photosynthesis and respiration as related to plant organs, stage of development and copper supply

    Directory of Open Access Journals (Sweden)

    St. Łyszcz

    2015-06-01

    Full Text Available Some experiments were performed to investigate the physiological role of copper in oat and sunflower and to recognize some effects of copper deficiency. Oat and sunflower plants were grown in pots on a peat soil under copper deficiency conditions (–Cu or with the optimal copper supply (+Cu. In plants the following measurements were carried out: 1 the activity of ascorbic acid oxidase (AAO and of catechol oxidase (PPO in different plant organs and at different stages of plant development, 2 the activity and the rate of photosynthesis, 3 the activity of RuDP-carboxylase, 4 the intensity of plant respiration. The activity of AAO and of PPO, and also the rate and the activity of photosynthesis were significantly lower under conditions of copper deficiency. The activity of both discussed oxidases depended on: 1 the plant species, 2 plant organs, 3 stage of plant development. Copper deficiency caused decrease of the respiration intensity of sunflower leaves but it increased to some extent the respiration of oat tops. Obtained results are consistent with the earlier suggestion of the authors that the PPO activity in sunflower leaves could be a sensitive indicator of copper supply of the plants, farther experiments are in progress.

  2. High rates of sulfate reduction in a low-sulfate hot spring microbial mat are driven by a low level of diversity of sulfate-respiring microorganisms

    DEFF Research Database (Denmark)

    Dillon, Jesse G; Fishbain, Susan; Miller, Scott R

    2007-01-01

    The importance of sulfate respiration in the microbial mat found in the low-sulfate thermal outflow of Mushroom Spring in Yellowstone National Park was evaluated using a combination of molecular, microelectrode, and radiotracer studies. Despite very low sulfate concentrations, this mat community...... was shown to sustain a highly active sulfur cycle. The highest rates of sulfate respiration were measured close to the surface of the mat late in the day when photosynthetic oxygen production ceased and were associated with a Thermodesulfovibrio-like population. Reduced activity at greater depths...... was correlated with novel populations of sulfate-reducing microorganisms, unrelated to characterized species, and most likely due to both sulfate and carbon limitation....

  3. Social motivation in prospective memory: higher importance ratings and reported performance rates for social tasks.

    Science.gov (United States)

    Penningroth, Suzanna L; Scott, Walter D; Freuen, Margaret

    2011-03-01

    Few studies have addressed social motivation in prospective memory (PM). In a pilot study and two main studies, we examined whether social PM tasks possess a motivational advantage over nonsocial PM tasks. In the pilot study and Study 1, participants listed their real-life important and less important PM tasks. Independent raters categorized the PM tasks as social or nonsocial. Results from both studies showed a higher proportion of tasks rated as social when important tasks were requested than when less important tasks were requested. In Study 1, participants also reported whether they had remembered to perform each PM task. Reported performance rates were higher for tasks rated as social than for those rated as nonsocial. Finally, in Study 2, participants rated the importance of two hypothetical PM tasks, one social and one nonsocial. The social PM task was rated higher in importance. Overall, these findings suggest that social PM tasks are viewed as more important than nonsocial PM tasks and they are more likely to be performed. We propose that consideration of the social relevance of PM will lead to a more complete and ecologically valid theoretical description of PM performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  4. Comparison of primary production and pelagic community respiration rates in the coastal zone of the Gulf of Gdansk

    Directory of Open Access Journals (Sweden)

    Joanna K. York

    2001-09-01

    Full Text Available The organic matter production/respiration balance in the coastal water column was examined, both the primary production and community respiration being measured with the oxygen light-and-dark bottle method. Community respiration (CR was always lower than the gross primary production (GPP measured at a standard light intensity of 390 µE m-2 s-1, which amounted, on average, to 30% of GPP. During most of the in situ sampling period, the coastal system (6-7 m depth was found to be autotrophic, with depth-integrated GPP ranging from 6.7 mmoles O2 m-2 d-1 in December to 214.2 mmoles O2 m-2 d-1 in August, and CR ranging correspondingly from 6.0 to 177.7 mmoles O2 m-2 d-1. However, on some occasions heterotrophic conditions were recorded: depth-integrated GPP

  5. [Effects of management regime on soil respiration from agroecosystems].

    Science.gov (United States)

    Chen, Shu-tao; Zhu, Da-wei; Niu, Chuan-po; Zou, Jian-wen; Wang, Chao; Sun, Wen-juan

    2009-10-15

    In order to examine the effects of management regime, such as nitrogen application and plowing method, on soil respiration from farmland, the static opaque chamber-gas chromatograph method was used to measure soil CO2 fluxes in situ. The field measurement was carried out for 5 growing seasons, which were the 2002-2003 wheat, 2003 maize and soybean, 2003-2004 wheat, 2004 maize and 2004-2005 wheat seasons. Our results showed that soil respiration increased in fertilizer-applied treatments compared with no fertilizer treatment after 3 times of fertilizer application on 9 November 2002, 14 February and 26 March 2003. And the most obvious increase appeared following the third fertilizer application. No significant difference in soil respiration was found among several fertilizer application treatments. The effect of plowing depth on soil respiration was contingent on preceding cropping practice. Over the 2003-2004 wheat-growing seasons (its preceding cropping practice was rice paddy), mean soil respiration rates were not significant different (p > 0.05) between no plowing treatment and shallow plowing treatment. The shallow plowing treatment CT2 led to higher soil CO2 losses compared with no plowing treatment of NT2 in the 2004 maize-growing season, however, the significant higher (p soil respiration rates occurred with no plowing treatment of NT3 in the following 2004-2005 wheat-growing season. Intensive plowing (25 cm depth), compared with no plowing practice (NT4), increased soil respiration significantly during the 2004-2005 wheat-growing season. Regression analysis showed that the exponential function could be employed to fit the relationship between soil respiration and temperature. The exponential relationship yielded the Q10 values which were varied from 1.26 to 3.60, with a mean value of 2.08. To evaluate the effect of temperature on soil respiration, the CO2 emission fluxes were normalized for each treatment and each crop growing season. Plotting the

  6. Simplified pressure method for respirator fit testing.

    Science.gov (United States)

    Han, D; Xu, M; Foo, S; Pilacinski, W; Willeke, K

    1991-08-01

    A simplified pressure method has been developed for fit testing air-purifying respirators. In this method, the air-purifying cartridges are replaced by a pressure-sensing attachment and a valve. While wearers hold their breath, a small pump extracts air from the respirator cavity until a steady-state pressure is reached in 1 to 2 sec. The flow rate through the face seal leak is a unique function of this pressure, which is determined once for all respirators, regardless of the respirator's cavity volume or deformation because of pliability. The contaminant concentration inside the respirator depends on the degree of dilution by the flow through the cartridges. The cartridge flow varies among different brands and is measured once for each brand. The ratio of cartridge to leakflow is a measure of fit. This flow ratio has been measured on human subjects and has been compared to fit factors determined on the same subjects by means of photometric and particle count tests. The aerosol tests gave higher values of fit.

  7. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Directory of Open Access Journals (Sweden)

    Zhen Wang

    Full Text Available Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2.s(-1 and clipping (2.06 μmol.m(-2.s(-1 than under grazing (1.65 μmol.m-(2.s(-1 over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP. Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content and biotic (ANPP and BNPP factors regulate soil respiration in the semiarid temperate grassland of northern China.

  8. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Science.gov (United States)

    Wang, Zhen; Ji, Lei; Hou, Xiangyang; Schellenberg, Michael P

    2016-01-01

    Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures) on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2).s(-1)) and clipping (2.06 μmol.m(-2).s(-1)) than under grazing (1.65 μmol.m-(2).s(-1)) over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP). Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP) and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content) and biotic (ANPP and BNPP) factors regulate soil respiration in the semiarid temperate grassland of northern China.

  9. Contribution of Root Respiration to Soil Respiration in Sugarcane Plantation in Thailand

    OpenAIRE

    Wilaiwan Sornpoon; Sebastien Bonnet; Poonpipope Kasemsap; Savitri Garivait

    2013-01-01

    The understanding on the contribution of root respiration to total soil respiration is still very limited, especially for sugarcane. In this study, trenching experiments in sugarcane plantations were conducted to separate and investigate soil respiration for this crop. The measurements were performed for the whole growing period of 344 days to quantify root respiration. The obtained monitoring data showed that the respiration rate is increasing with the age of the plant, accounting for up to ...

  10. Graduation Rates and the Higher Education Demographic Evolution

    Science.gov (United States)

    Hunsaker, B. Tom; Thomas, Douglas E.

    2013-01-01

    In his 1918 orienting work, The Higher Learning in America, Veblen highlights two primary aims of the higher education institution: (a) scientific and scholarly inquiry, and (b) the instruction of students (Veblen, 1918). As of 2006, this overarching mission remained intact. In contemporary literature, a common measure of the efficacy of the…

  11. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    DEFF Research Database (Denmark)

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...

  12. Cattle respiration facility

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Lund, Peter; Weisbjerg, Martin Riis

    2012-01-01

    In Denmark, the emission rate of methane from dairy cows has been calculated using the IPCC standard values for dairy cows in Western countries, due to the lack of national data. Therefore, four respiration chambers for dairy cows were built with the main purpose of measuring methane, but also...

  13. Temperature response of soil respiration largely unaltered with experimental warming

    Science.gov (United States)

    Carey, Joanna C.; Tang, Jianwu; Templer, Pamela H.; Kroeger, Kevin D.; Crowther, Thomas W.; Burton, Andrew J.; Dukes, Jeffrey S.; Emmett, Bridget; Frey, Serita D.; Heskel, Mary A.; Jiang, Lifen; Machmuller, Megan B.; Mohan, Jacqueline; Panetta, Anne Marie; Reich, Peter B.; Reinsch, Sabine; Wang, Xin; Allison, Steven D.; Bamminger, Chris; Bridgham, Scott; Collins, Scott L.; de Dato, Giovanbattista; Eddy, William C.; Enquist, Brian J.; Estiarte, Marc; Harte, John; Henderson, Amanda; Johnson, Bart R.; Steenberg Larsen, Klaus; Luo, Yiqi; Marhan, Sven; Melillo, Jerry M.; Penuelas, Josep; Pfeifer-Meister, Laurel; Poll, Christian; Rastetter, Edward B.; Reinmann, Andrew B.; Reynolds, Lorien L.; Schmidt, Inger K.; Shaver, Gaius R.; Strong, Aaron L.; Suseela, Vidya; Tietema, Albert

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies, spanning nine biomes and over 2 decades of warming. Our analysis reveals no significant differences in the temperature sensitivity of soil respiration between control and warmed plots in all biomes, with the exception of deserts and boreal forests. Thus, our data provide limited evidence of acclimation of soil respiration to experimental warming in several major biome types, contrary to the results from multiple single-site studies. Moreover, across all nondesert biomes, respiration rates with and without experimental warming follow a Gaussian response, increasing with soil temperature up to a threshold of ∼25 °C, above which respiration rates decrease with further increases in temperature. This consistent decrease in temperature sensitivity at higher temperatures demonstrates that rising global temperatures may result in regionally variable responses in soil respiration, with colder climates being considerably more responsive to increased ambient temperatures compared with warmer regions. Our analysis adds a unique cross-biome perspective on the temperature response of soil respiration, information critical to improving our mechanistic understanding of how soil carbon dynamics change with climatic warming.

  14. Respiration and substrate transport rates as well as reactive oxygen species production distinguish mitochondria from brain and liver.

    Science.gov (United States)

    Gusdon, Aaron M; Fernandez-Bueno, Gabriel A; Wohlgemuth, Stephanie; Fernandez, Jenelle; Chen, Jing; Mathews, Clayton E

    2015-09-10

    Aberrant mitochondrial function, including excessive reactive oxygen species (ROS) production, has been implicated in the pathogenesis of human diseases. The use of mitochondrial inhibitors to ascertain the sites in the electron transport chain (ETC) resulting in altered ROS production can be an important tool. However, the response of mouse mitochondria to ETC inhibitors has not been thoroughly assessed. Here we set out to characterize the differences in phenotypic response to ETC inhibitors between the more energetically demanding brain mitochondria and less energetically demanding liver mitochondria in commonly utilized C57BL/6J mice. We show that in contrast to brain mitochondria, inhibiting distally within complex I or within complex III does not increase liver mitochondrial ROS production supported by complex I substrates, and liver mitochondrial ROS production supported by complex II substrates occurred primarily independent of membrane potential. Complex I, II, and III enzymatic activities and membrane potential were equivalent between liver and brain and responded to ETC. inhibitors similarly. Brain mitochondria exhibited an approximately two-fold increase in complex I and II supported respiration compared with liver mitochondria while exhibiting similar responses to inhibitors. Elevated NADH transport and heightened complex II-III coupled activity accounted for increased complex I and II supported respiration, respectively in brain mitochondria. We conclude that important mechanistic differences exist between mouse liver and brain mitochondria and that mouse mitochondria exhibit phenotypic differences compared with mitochondria from other species.

  15. Respiration rates in subsurface waters of the northern Indian Ocean: Evidence for low decomposition rates of organic matter within the water column in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Shailaja, M.S.; DileepKumar, M.; Sengupta, R.

    measured in the Arabian Sea. Lower respiratin rates in the Bay of Bengal are corroborated by the much weaker north-south gradients in oxygen and total carbon dioxide. These are, however, in conflict with the higher sinking fluxes of organic carbon measured...

  16. ESTIMATING RETURN RATE OF HIGHER EDUCATION FUND IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Semenikhina V. A.

    2014-06-01

    Full Text Available Currently, the Russian government pays great attention to the field of higher and postgraduate education. But in the Russian scientific literature there are gaps related to the effectiveness of the overall evaluation of the higher education sector. The article dwells upon the problem of interregional income spread of the Russian population. Empirical estimator of difference influence accounting for human capital accumulated in Russian regions on wage levels and maximum increase of total wage levels and population income for 2001-2011 is carried out. Higher education, exceeding the influence of accumulated volume of the main funds, has a great influence on income spread in Russian regions. Besides, increase of higher education fund in Russian regions contributes to the population’s wage increase and growth in income, but at the same time it decreases legal wages. Results of the study extend knowledge of the economics of education of the Russian Federation.

  17. Emotional Competence and Drop-Out Rates in Higher Education

    Science.gov (United States)

    Kingston, Emma

    2008-01-01

    Purpose: The purpose of this paper is to compare the emotional competence of first year undergraduates enrolled on a high or low drop-out rate (HDR and LDR, respectively) course, at a newly established university within the UK. Design/methodology/approach: A mixed methods approach using both quantitative and qualitative data collection methods was…

  18. Student Ratings of Instruction in Turkish Higher Education

    Directory of Open Access Journals (Sweden)

    Nehir Sert

    2013-05-01

    Full Text Available The end-of-term student evaluations have a twofold purpose: to provide information for administrators to make personnel decisions, and to help instructors to improve the quality of their teaching. The aim of this study is to investigate the ‘utility’ of the Student Ratings of Instruction (SRI. To that end, the concerns of the administrators, instructors and students regarding the use of the SRI in formative and summative evaluations are questioned. This study also investigates possible variables associated with the SRI: 1 what are the differences in ratings among the below-average, average and the above-average students? and 2 what is the correlation between the students’ grades and ratings? The participants of the study consisted of 5 administrators, 17 instructors and 292 students from the faculty of education of a foundation university in Ankara. A triangulation of quantitative and qualitative methods was adopted. In the first phase, causal comparative and correlation research methods were implemented. In the second phase, qualitative data were collected through semi-structured interviews. The results revealed that there was no significant difference in the SRI among the below-average, average and above-average students. The correlation between the student grades and the SRI was significant at a low level. The SRI were reportedly utilised to make teaching more effective and to make decisions when employing part-time personnel only. The permanent personnel were not affected by the SRI. Suggestions have been put forward to verify the usefulness of SRI.

  19. Pore-scale investigation on the response of heterotrophic respiration to moisture conditions in heterogeneous soils

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Zhifeng; Liu, Chongxuan; Todd-Brown, Katherine E.; Liu, Yuanyuan; Bond-Lamberty, Ben; Bailey, Vanessa L.

    2016-11-15

    The relationship between microbial respiration rate and soil moisture content is an important property for understanding and predicting soil organic carbon degradation, CO2 production and emission, and their subsequent effects on climate change. This paper reports a pore-scale modeling study to investigate the response of heterotrophic respiration to moisture conditions in soils and to evaluate various factors that affect this response. X-ray computed tomography was used to derive soil pore structures, which were then used for pore-scale model investigation. The pore-scale results were then averaged to calculate the effective respiration rates as a function of water content in soils. The calculated effective respiration rate first increases and then decreases with increasing soil water content, showing a maximum respiration rate at water saturation degree of 0.75 that is consistent with field and laboratory observations. The relationship between the respiration rate and moisture content is affected by various factors, including pore-scale organic carbon bioavailability, the rate of oxygen delivery, soil pore structure and physical heterogeneity, soil clay content, and microbial drought resistivity. Simulations also illustrates that a larger fraction of CO2 produced from microbial respiration can be accumulated inside soil cores under higher saturation conditions, implying that CO2 flux measured on the top of soil cores may underestimate or overestimate true soil respiration rates under dynamic moisture conditions. Overall, this study provides mechanistic insights into the soil respiration response to the change in moisture conditions, and reveals a complex relationship between heterotrophic microbial respiration rate and moisture content in soils that is affected by various hydrological, geochemical, and biophysical factors.

  20. Expensive Brains: “Brainy” Rodents have Higher Metabolic Rate

    Science.gov (United States)

    Sobrero, Raúl; May-Collado, Laura J.; Agnarsson, Ingi; Hernández, Cristián E.

    2011-01-01

    Brains are the centers of the nervous system of animals, controlling the organ systems of the body and coordinating responses to changes in the ecological and social environment. The evolution of traits that correlate with cognitive ability, such as relative brain size is thus of broad interest. Brain mass relative to body mass (BM) varies among mammals, and diverse factors have been proposed to explain this variation. A recent study provided evidence that energetics play an important role in brain evolution (Isler and van Schaik, 2006). Using composite phylogenies and data drawn from multiple sources, these authors showed that basal metabolic rate (BMR) correlates with brain mass across mammals. However, no such relationship was found within rodents. Here we re-examined the relationship between BMR and brain mass within Rodentia using a novel species-level phylogeny. Our results are sensitive to parameter evaluation; in particular how species mass is estimated. We detect no pattern when applying an approach used by previous studies, where each species BM is represented by two different numbers, one being the individual that happened to be used for BMR estimates of that species. However, this approach may compromise the analysis. When using a single value of BM for each species, whether representing a single individual, or available species mean, our findings provide evidence that brain mass (independent of BM) and BMR are correlated. These findings are thus consistent with the hypothesis that large brains evolve when the payoff for increased brain mass is greater than the energetic cost they incur. PMID:21811456

  1. Effects of cadmium, zinc, lead, and mercury on respiration and fermentation of Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Grafl, H J; Schwantes, H O

    1983-01-01

    Zinc and lead did not affect the rate of respiration and fermentation. Concentrations of cadmium higher than 10/sup -7/ M and concentrations of mercury higher than 5 x 10/sup -5/ M significantly reduced the O/sub 2/ consumption and the CO/sub 2/ production. 10/sup -2/ M cadmium and 10/sup -3/ M mercury completely inhibited respiration and fermentation. Low concentrations of mercury inhibited respiration irreversibly and fermentation reversibly. High concentrations of zinc reduced the toxicity of low concentrations of cadmium but they enhanced the effects of high concentrations of cadmium and mercury. No interactions between lead and the other tested heavy metals were observed.

  2. Shifts in mass-scaling of respiration, feeding, and growth rates across life-form transitions in marine pelagic organisms

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Hirst, Andrew G.

    2014-01-01

    The metabolic rate of organisms may be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law, or it may be considered a property of the organism that emerges as a result of the adaptation to the environ...... and be the result of the optimization of trade-offs that allow sufficient feeding and growth rates to balance mortality...

  3. [Effects of Tillage on Soil Respiration and Root Respiration Under Rain-Fed Summer Corn Field].

    Science.gov (United States)

    Lu, Xing-li; Liao, Yun-cheng

    2015-06-01

    To explore the effects of different tillage systems on soil respiration and root respiration under rain-fed condition. Based on a short-term experiment, this paper investigated soil respiration in summer corn growth season under four tillage treatments including subsoiling tillage (ST), no tillage (NT), rotary tillage (RT) and moldboard plow tillage (CT). The contribution of root respiration using root exclusion method was also discussed. The results showed that soil respiration rate presented a single peak trend under four tillage methods during the summer corn growing season, and the maximum value was recorded at the heading stage. The trends of soil respiration were as follows: heading stage > flowering stage > grain filling stage > maturity stage > jointing stage > seedling stage. The trends of soil respiration under different tillage systems were as follows: CT > ST > RT > NT. There was a significant correlation between soil respiration rate and soil temperatures (P soil respiration using exponential function equation. However, there was no significant correlation between soil respiration rate and soil moisture. Root respiration accounted for 45.13%-56.86% of the proportion of soil respiratio n with the mean value 51.72% during the summer corn growing season under different tillage systems. Therefore, root exclusion method could be used to study the contribution of crop growth to carbon emission, to compare effects of different tillage systems on the contribution of root respiration provides the bases for selecting the measures to slow down the decomposition of soil carbon.

  4. Effect of Simvastatin, Coenzyme Q10, Resveratrol, Acetylcysteine and Acetylcarnitine on Mitochondrial Respiration.

    Science.gov (United States)

    Fišar, Z; Hroudová, J; Singh, N; Kopřivová, A; Macečková, D

    2016-01-01

    Some therapeutic and/or adverse effects of drugs may be related to their effects on mitochondrial function. The effects of simvastatin, resveratrol, coenzyme Q10, acetylcysteine, and acetylcarnitine on Complex I-, Complex II-, or Complex IV-linked respiratory rate were determined in isolated brain mitochondria. The protective effects of these biologically active compounds on the calcium-induced decrease of the respiratory rate were also studied. We observed a significant inhibitory effect of simvastatin on mitochondrial respiration (IC50 = 24.0 μM for Complex I-linked respiration, IC50 = 31.3 μM for Complex II-linked respiration, and IC50 = 42.9 μM for Complex IV-linked respiration); the inhibitory effect of resveratrol was found at very high concentrations (IC50 = 162 μM for Complex I-linked respiration, IC50 = 564 μM for Complex II-linked respiration, and IC50 = 1454 μM for Complex IV-linked respiration). Concentrations required for effective simvastatin- or resveratrol-induced inhibition of mitochondrial respiration were found much higher than concentrations achieved under standard dosing of these drugs. Acetylcysteine and acetylcarnitine did not affect the oxygen consumption rate of mitochondria. Coenzyme Q10 induced an increase of Complex I-linked respiration. The increase of free calcium ions induced partial inhibition of the Complex I+II-linked mitochondrial respiration, and all tested drugs counteracted this inhibition. None of the tested drugs showed mitochondrial toxicity (characterized by respiratory rate inhibition) at drug concentrations achieved at therapeutic drug intake. Resveratrol, simvastatin, and acetylcarnitine had the greatest neuroprotective potential (characterized by protective effects against calcium-induced reduction of the respiratory rate).

  5. Growth response of Douglas-fir seedlings to nitrogen fertilization: importance of Rubisco activation state and respiration rates.

    Science.gov (United States)

    Daniel K. Manter; Kathleen L. Kavanagh; Cathy L. Rose

    2005-01-01

    High foliar nitrogen concentration ([N]) is associated with high rates of photosynthesis and thus high tree productivity; however, at excessive [N], tree productivity is reduced. Reports of excessive [N] in the Douglas-fir forests of the Oregon Coast Range prompted this investigation of growth and needle physiological responses to increasing foliar N concentrations in...

  6. Contribution of bacterial respiration to plankton respiration from 50°N to 44°S in the Atlantic Ocean

    Science.gov (United States)

    García-Martín, E. E.; Aranguren-Gassis, M.; Hartmann, M.; Zubkov, M. V.; Serret, P.

    2017-11-01

    Marine bacteria play an important role in the global cycling of carbon and therefore in climate regulation. However, the paucity of direct measurements means that our understanding of the magnitude and variability of bacterial respiration in the ocean is poor. Estimations of respiration in the 0.2-0.8 μm size-fraction (considered as bacterial respiration), total plankton community respiration, and the contribution of bacterial respiration to total plankton community respiration were made along two latitudinal transects in the Atlantic Ocean (ca. 50°N-44°S) during 2010 and 2011. Two different methodologies were used: determination of changes in dissolved O2 concentration after standard 24 h dark bottle incubations, and measurements of in vivo reduction of 2-(ρ-iodophenyl)-3-(ρ-nitrophenyl)-5phenyl tetrazolium salt (INT). There was an overall significant correlation (r = 0.44, p community respiration estimated by both methods. Depth-integrated community respiration varied as much as threefold between regions. Maximum rates occurred in waters of the western European shelf and Patagonian shelf, and minimum rates in the North and South oligotrophic gyres. Depth-integrated bacterial respiration followed the same pattern as community respiration. There was a significantly higher cell-specific bacterial respiration in the northern subtropical gyre than in the southern subtropical gyre which suggests that bacterial carbon turnover is faster in the northern gyre. The relationships between plankton respiration and physicochemical and biological variables were different in different years. In general, INTT was correlated to both chlorophyll-a and bacterial abundance, while INT0.2-0.8 was only correlated with bacterial abundance. However, in 2010 INTT and INT0.2-0.8 were also correlated with temperature and primary production while in 2011 they were correlated with nitrate + nitrite concentration. The bacterial contribution to depth integrated community respiration was

  7. Activity of the respiratory electron transport system and respiration rates within the oxygen minimum layer of the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Shailaja, M.S.

    rates. The depth profiles representing observations off Peru and Mexico are also shown. It may be noted that the measurements off Mexico were made with a method similar to that followed by us (GARFIELD et al., 1983). On the other hand, the Peruvian... judging from the nitrate deficit, nitrite and nitrous oxide distributions (NAQvI and NORONHA, 1991). OXYGEN CONSUMPTION (nl./t/h) 0 q 20 40 60 80 , n i I i I00 Off Mexico • • /~ "f~ Off Peru o o / 200 ,o ~ ~ - o o I • " e o //-o-./ - - 400 tR~•7...

  8. Effect of Anoxia on Respiration Rate (Fermentative Index and Ethanol Production of Onion Bulbs (Allium cepa L.

    Directory of Open Access Journals (Sweden)

    N. Benkeblia

    2003-01-01

    Full Text Available The physiological behavior, including carbon dioxide production, fermentative index (FI and ethanolic production of onion bulbs kept under total anoxia (l00% N2 was investigated. During the first 24 hours, carbon dioxide production increased from 0.01 to 1.56 kPa Co2, and the average rate of the increase in CO2; production between 0 and 24 hours was 0.09 kPa/h. The Q10, of the fermentative index was l.9. Ethanol produced by onion bulbs kept under anoxia during 6 hours was temperature dependent, and was 0.563 and 0.760 pmol kg-1h-1 at 10 and 20°C respectively, while at 4°C the quantity produced was not detected. It is concluded that onion seems to be less tolerant to anoxia than other vegetables such as artichoke, cauliflower, tomato, potato and asparagus.

  9. EXPERIMENTAL SUBSTANTIATION OF PERMEABILIZED HEPATOCYTES MODEL FOR INVESTIGATION OF MITOCHONDRIA IN SITU RESPIRATION.

    Science.gov (United States)

    Merlavsky, V M; Manko, B O; Ikkert, O V; Manko, V V

    2015-01-01

    To verify experimentally the model of permeabilized hepatocytes, the degree of cell permeability was assessed using trypan blue and polarographycally determined cell respiration rate upon succinate (0.35 mM) and a-ketoglutarate (1 mM) oxidation. Oxidative phosphorylation was stimulated by ADP (750 μM). Hepatocyte permeabilization depends on digitonin concentraion in medium and on the number of cells in suspension. Thus, the permeabilization of 0.9-1.7 million cells/ml was completed by 25 μg/ml of digitonin, permeabilization of 2.0-3.0 million cells/ml--by 50 μg/ml of digitonin and permeabilization of 4.0-5.6 million cells/ml--by 100 μg/ml. Thus, the higher is the suspension density, the higher digitonin concentration is required. Treatment of hepatocytes with digitonin resulted in a decrease of endogenous respiration rate to a minimum upon 20-22 μg of digitonin per 1 million cells. Supplementation of permeabilized hepatocytes with α-ketoglutarate maintained stable respiration rate, on the level higher than endogenous respiration at the corresponding digitonin concentration, unlike the intact cells. Respiration rate of permeabilized hepatocytes at the simultaneous addition of α-ketoglutarate and ADP increased to the level of intact cell respiration, irrespective of digitonin concentration. Addition of solely succinate and especially succinate plus ADP markedly intensified the respiration of permeabilized hepatocytes to the level higher than that of intact cells. The dependence of succinate-stimulated respiration on digitonin concentration reached maximum at 20-22 αg of digitonin per 1 million cells. Optimal ratio of digitonin amount and the cell number in suspension is expected to be different in various tissues.

  10. Gaseous elemental mercury emissions and CO{sub 2} respiration rates in terrestrial soils under controlled aerobic and anaerobic laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Obrist, Daniel, E-mail: daniel.obrist@dri.edu [Desert Research Institute, Division of Atmospheric Sciences, 2215 Raggio Parkway, Reno, Nevada, 89512 (United States); Fain, Xavier; Berger, Carsen [Desert Research Institute, Division of Atmospheric Sciences, 2215 Raggio Parkway, Reno, Nevada, 89512 (United States)

    2010-03-01

    Mercury (Hg) levels in terrestrial soils are linked to the presence of organic carbon (C). Carbon pools are highly dynamic and subject to mineralization processes, but little is known about the fate of Hg during decomposition. This study evaluated relationships between gaseous Hg emissions from soils and carbon dioxide (CO{sub 2}) respiration under controlled laboratory conditions to assess potential losses of Hg to the atmosphere during C mineralization. Results showed a linear correlation (r{sup 2} = 0.49) between Hg and CO{sub 2} emissions in 41 soil samples, an effect unlikely to be caused by temperature, radiation, different Hg contents, or soil moisture. Stoichiometric comparisons of Hg/C ratios of emissions and underlying soil substrates suggest that 3% of soil Hg was subject to evasion. Even minute emissions of Hg upon mineralization, however, may be important on a global scale given the large Hg pools sequestered in terrestrial soils and C stocks. We induced changes in CO{sub 2} respiration rates and observed Hg flux responses, including inducement of anaerobic conditions by changing chamber air supply from N{sub 2}/O{sub 2} (80% and 20%, respectively) to pure N{sub 2}. Unexpectedly, Hg emissions almost quadrupled after O{sub 2} deprivation while oxidative mineralization (i.e., CO{sub 2} emissions) was greatly reduced. This Hg flux response to anaerobic conditions was lacking when repeated with sterilized soils, possibly due to involvement of microbial reduction of Hg{sup 2+} by anaerobes or indirect abiotic effects such as alterations in soil redox conditions. This study provides experimental evidence that Hg volatilization, and possibly Hg{sup 2+} reduction, is related to O{sub 2} availability in soils from two Sierra Nevada forests. If this result is confirmed in soils from other areas, the implication is that Hg volatilization from terrestrial soils is partially controlled by soil aeration and that low soil O{sub 2} levels and possibly low soil redox

  11. Management effects on European cropland respiration

    DEFF Research Database (Denmark)

    Eugster, Werner; Moffat, Antje M.; Ceschia, Eric

    2010-01-01

    Increases in respiration rates following management activities in croplands are considered a relevant anthropogenic source of CO2. In this paper, we quantify the impact of management events on cropland respiration fluxes of CO2 as they occur under current climate and management conditions. Our....... This allowed us to address the question of how management activities influence ecosystem respiration. This was done by comparing respiration fluxes during 7, 14, and 28 days after the management with those observed during the matching time period before management. Median increases in respiration ranged from...... than management alone are also important at a given site. Temperature is the climatic factor that showed best correlation with site-specific respiration fluxes. Therefore, the effect of temperature changes between the time periods before and after management were taken into account for a subset of 13...

  12. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    DEFF Research Database (Denmark)

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I

    2014-01-01

    , skeletal, and smooth muscle was harvested from a total of 22 subjects (53±6 yrs) and mitochondrial respiration assessed in permeabilized fibers. Complex I+II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac, skeletal, to smooth muscle (54±1; 39±4; 15......±1 pmol•s(-1)•mg (-1), prespiration rates were normalized by CS (respiration...... per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, Complex I state 2 normalized for CS activity, an index of non-phosphorylating respiration per mitochondrial content, increased progressively from cardiac, skeletal...

  13. Respirator field performance factors

    International Nuclear Information System (INIS)

    Skaggs, B.J.; DeField, J.D.; Strandberg, S.W.; Sutcliffe, C.R.

    1985-01-01

    The Industrial Hygiene Group assisted OSHA and the NRC in measurements of respirator performance under field conditions. They reviewed problems associated with sampling aerosols within the respirator in order to determine fit factors (FFs) or field performance factor (FPF). In addition, they designed an environmental chamber study to determine the effects of temperature and humidity on a respirator wearer

  14. On the relative roles of hydrology, salinity, temperature, and root productivity in controlling soil respiration from coastal swamps (freshwater)

    Science.gov (United States)

    Krauss, Ken W.; Whitbeck, Julie L.; Howard, Rebecca J.

    2012-01-01

    Background and aims Soil CO2 emissions can dominate gaseous carbon losses from forested wetlands (swamps), especially those positioned in coastal environments. Understanding the varied roles of hydroperiod, salinity, temperature, and root productivity on soil respiration is important in discerning how carbon balances may shift as freshwater swamps retreat inland with sea-level rise and salinity incursion, and convert to mixed communities with marsh plants. Methods We exposed soil mesocosms to combinations of permanent flooding, tide, and salinity, and tracked soil respiration over 2 1/2 growing seasons. We also related these measurements to rates from field sites along the lower Savannah River, Georgia, USA. Soil temperature and root productivity were assessed simultaneously for both experiments. Results Soil respiration from mesocosms (22.7-1678.2 mg CO2 m-2 h-1) differed significantly among treatments during four of the seven sampling intervals, where permanently flooded treatments contributed to low rates of soil respiration and tidally flooded treatments sometimes contributed to higher rates. Permanent flooding reduced the overall capacity for soil respiration as soils warmed. Salinity did reduce soil respiration at times in tidal treatments, indicating that salinity may affect the amount of CO2 respired with tide more strongly than under permanent flooding. However, soil respiration related greatest to root biomass (mesocosm) and standing root length (field); any stress reducing root productivity (incl. salinity and permanent flooding) therefore reduces soil respiration. Conclusions Overall, we hypothesized a stronger, direct role for salinity on soil respiration, and found that salinity effects were being masked by varied capacities for increases in respiration with soil warming as dictated by hydrology, and the indirect influence that salinity can have on plant productivity.

  15. Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.

    Directory of Open Access Journals (Sweden)

    Guangxuan Han

    Full Text Available Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively. During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2 s(-1, followed by the Suaeda salsa site (0.77 µmol CO2 m(-2 s(-1 and the bare soil site (0.41 µmol CO2 m(-2 s(-1. The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland.

  16. Vegetation Types Alter Soil Respiration and Its Temperature Sensitivity at the Field Scale in an Estuary Wetland

    Science.gov (United States)

    Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

    2014-01-01

    Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q 10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m−2 s−1), followed by the Suaeda salsa site (0.77 µmol CO2 m−2 s−1) and the bare soil site (0.41 µmol CO2 m−2 s−1). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

  17. Shrub encroachment alters sensitivity of soil respiration to temperature and moisture

    Science.gov (United States)

    Cable, Jessica M.; Barron-Gafford, Greg A.; Ogle, Kiona; Pavao-Zuckerman, Mitchell; Scott, Russell L.; Williams, David G.; Huxman, Travis E.

    2012-03-01

    A greater abundance of shrubs in semiarid grasslands affects the spatial patterns of soil temperature, moisture, and litter, resulting in fertile islands with potentially enhanced soil metabolic activity. The goal of this study was to quantify the microsite specificity of soil respiration in a semiarid riparian ecosystem experiencing shrub encroachment. We quantified the response of soil respiration to different microsite conditions created by big mesquite shrubs (near the trunk and the canopy edge), medium-sized mesquite, sacaton bunchgrasses, and open spaces. We hypothesized that soil respiration would be more temperature sensitive and less moisture sensitive and have a greater magnitude in shrub microsites compared with grass and open microsites. Field and incubation soil respiration data were simultaneously analyzed in a Bayesian framework to quantify the microsite-specific temperature and moisture sensitivities and magnitude of respiration. The analysis showed that shrub expansion increases the heterogeneity of respiration. Respiration has greater temperature sensitivity near the shrub canopy edge, and respiration rates are higher overall under big mesquite compared with those of the other microsites. Respiration in the microsites beneath medium-sized mesquites does not behave like a downscaled version of big mesquite microsites. The grass microsites show more similarity to big mesquite microsites than medium-sized shrubs. This study shows there can be a great deal of fine-scale spatial heterogeneity that accompanies shifts in vegetation structure. Such complexity presents a challenge in scaling soil respiration fluxes to the landscape for systems experiencing shrub encroachment, but quantifying this complexity is significantly important in determining overall ecosystem metabolic behavior.

  18. United States private schools have higher rates of exemptions to school immunization requirements than public schools.

    Science.gov (United States)

    Shaw, Jana; Tserenpuntsag, Boldtsetseg; McNutt, Louise-Anne; Halsey, Neal

    2014-07-01

    To compare medical, religious, and personal belief immunization exemption rates between private and public schools in US. Exemption rates were calculated using the Centers for Disease Control and Prevention School Immunization Assessment Surveys for the 2009-2010 school year excluding states with incomplete survey data. Standardized exemption rates weighted on enrollments in public and private schools were calculated. Differences in exemption rates between public and private schools were tested using Wilcoxon signed rank test. The overall state exemption rate was higher in US private than public schools, 4.25% (SD 4.27) vs 1.91% (1.67), P = .0001 and private schools had higher exemption rates for all types of exemptions; medical 0.58% (0.71) vs 0.34% (0.34) respectively (P = .0004), religious 2.09% (3.14) vs 0.83% (1.05) respectively (P = .0001), and personal belief 6.10% (4.12) vs 2.79% (1.57), respectively (P = .006). Overall exemption rates were significantly higher in states that allowed personal belief exemptions. Exemption rates were significantly higher in US private than in public schools. Children attending private schools may be at higher risk of vaccine-preventable diseases than public school children. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Nutrients and temperature additively increase stream microbial respiration

    Science.gov (United States)

    David W. P. Manning; Amy D. Rosemond; Vladislav Gulis; Jonathan P. Benstead; John S. Kominoski

    2017-01-01

    Rising temperatures and nutrient enrichment are co‐occurring global‐change drivers that stimulate microbial respiration of detrital carbon, but nutrient effects on the temperature dependence of respiration in aquatic ecosystems remain uncertain. We measured respiration rates associated with leaf litter, wood, and fine benthic organic matter (FBOM) across...

  20. Quantifying soil respiration at landscape scales. Chapter 11

    Science.gov (United States)

    John B. Bradford; Michael G. Ryan

    2008-01-01

    Soil CO2, efflux, or soil respiration, represents a substantial component of carbon cycling in terrestrial ecosystems. Consequently, quantifying soil respiration over large areas and long time periods is an increasingly important goal. However, soil respiration rates vary dramatically in space and time in response to both environmental conditions...

  1. Tropical rainforest carbon sink declines during El Niño as a result of reduced photosynthesis and increased respiration rates.

    Science.gov (United States)

    Cavaleri, Molly A; Coble, Adam P; Ryan, Michael G; Bauerle, William L; Loescher, Henry W; Oberbauer, Steven F

    2017-10-01

    Changes in tropical forest carbon sink strength during El Niño Southern Oscillation (ENSO) events can indicate future behavior under climate change. Previous studies revealed ˜6 Mg C ha -1  yr -1 lower net ecosystem production (NEP) during ENSO year 1998 compared with non-ENSO year 2000 in a Costa Rican tropical rainforest. We explored environmental drivers of this change and examined the contributions of ecosystem respiration (RE) and gross primary production (GPP) to this weakened carbon sink. For 1998-2000, we estimated RE using chamber-based respiration measurements, and we estimated GPP in two ways: using (1) the canopy process model MAESTRA, and (2) combined eddy covariance and chamber respiration data. MAESTRA-estimated GPP did not statistically differ from GPP estimated using approach 2, but was ˜ 28% greater than published GPP estimates for the same site and years using eddy covariance data only. A 7% increase in RE (primarily increased soil respiration) and a 10% reduction in GPP contributed equally to the difference in NEP between ENSO year 1998 and non-ENSO year 2000. A warming and drying climate for tropical forests may yield a weakened carbon sink from both decreased GPP and increased RE. Understanding physiological acclimation will be critical for the large carbon stores in these ecosystems. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  2. Soil respiration in different agricultural and natural ecosystems in an arid region.

    Directory of Open Access Journals (Sweden)

    Liming Lai

    Full Text Available The variation of different ecosystems on the terrestrial carbon balance is predicted to be large. We investigated a typical arid region with widespread saline/alkaline soils, and evaluated soil respiration of different agricultural and natural ecosystems. Soil respiration for five ecosystems together with soil temperature, soil moisture, soil pH, soil electric conductivity and soil organic carbon content were investigated in the field. Comparing with the natural ecosystems, the mean seasonal soil respiration rates of the agricultural ecosystems were 96%-386% higher and agricultural ecosystems exhibited lower CO(2 absorption by the saline/alkaline soil. Soil temperature and moisture together explained 48%, 86%, 84%, 54% and 54% of the seasonal variations of soil respiration in the five ecosystems, respectively. There was a significant negative relationship between soil respiration and soil electrical conductivity, but a weak correlation between soil respiration and soil pH or soil organic carbon content. Our results showed that soil CO(2 emissions were significantly different among different agricultural and natural ecosystems, although we caution that this was an observational, not manipulative, study. Temperature at the soil surface and electric conductivity were the main driving factors of soil respiration across the five ecosystems. Care should be taken when converting native vegetation into cropland from the point of view of greenhouse gas emissions.

  3. Soil respiration in different agricultural and natural ecosystems in an arid region.

    Science.gov (United States)

    Lai, Liming; Zhao, Xuechun; Jiang, Lianhe; Wang, Yongji; Luo, Liangguo; Zheng, Yuanrun; Chen, Xi; Rimmington, Glyn M

    2012-01-01

    The variation of different ecosystems on the terrestrial carbon balance is predicted to be large. We investigated a typical arid region with widespread saline/alkaline soils, and evaluated soil respiration of different agricultural and natural ecosystems. Soil respiration for five ecosystems together with soil temperature, soil moisture, soil pH, soil electric conductivity and soil organic carbon content were investigated in the field. Comparing with the natural ecosystems, the mean seasonal soil respiration rates of the agricultural ecosystems were 96%-386% higher and agricultural ecosystems exhibited lower CO(2) absorption by the saline/alkaline soil. Soil temperature and moisture together explained 48%, 86%, 84%, 54% and 54% of the seasonal variations of soil respiration in the five ecosystems, respectively. There was a significant negative relationship between soil respiration and soil electrical conductivity, but a weak correlation between soil respiration and soil pH or soil organic carbon content. Our results showed that soil CO(2) emissions were significantly different among different agricultural and natural ecosystems, although we caution that this was an observational, not manipulative, study. Temperature at the soil surface and electric conductivity were the main driving factors of soil respiration across the five ecosystems. Care should be taken when converting native vegetation into cropland from the point of view of greenhouse gas emissions.

  4. Forest harvesting effects on soil temperature, moisture, and respiration in a bottomland hardwood forest

    International Nuclear Information System (INIS)

    Londo, A.J.; Messina, M.G.; Schoenholtz, S.H.

    1999-01-01

    The effect of forest disturbance on C cycling has become an issue, given concerns about escalating atmospheric C content. The authors examined the effects of harvest intensity on in situ and laboratory mineral soil respiration in an East Texas bottomland hardwood forest between 6 and 22 mo after harvesting. Treatments included a clearcut, a partial cut wherein approximately 58% of the basal area was removed, and an unharvested control. The soda-lime absorption technique was used for in situ respiration (CO 2 efflux) and the wet alkali method (NaOH) was used for laboratory mineral soil respiration. Soil temperature and moisture content were also measured. Harvesting significantly increased in situ respiration during most sampling periods. This effect was attributed to an increase in live root and microflora activity associated with postharvesting revegetation. In situ respiration increased exponentially (Q 10 relationship) as treatment soil temperatures increased, but followed a parabolic-type pattern through the range of soil moisture measured (mean range 10.4--31.5%). Mean rates of laboratory mineral soil respiration measured during the study were unaffected by cutting treatment for most sampling sessions. Overall, the mean rate of CO 2 efflux in the clearcuts was significantly higher than that in the partial cuts, which in turn was significantly higher than that in the controls. Mass balance estimates indicate that these treatment differences will have little or no long-term effect on C sequestration of these managed forests

  5. Soil fauna communities and microbial respiration in high Arctic tundra soils at Zackenberg, Northeast Greenland

    DEFF Research Database (Denmark)

    Sørensen, Louise I.; Holmstrup, Martin; Maraldo, Kristine

    2006-01-01

    The soil fauna communities were described for three dominant vegetation types in a high arctic site at Zackenberg, Northeast Greenland. Soil samples were extracted to quantify the densities of mites, collembolans, enchytraeids, diptera larvae, nematodes and protozoa. Rates of microbial respiration...... densities (naked amoeba and heterotrophic flagellates) were equal. Respiration rate of unamended soil was similar in soil from the three plots. However, a higher respiration rate increase in carbon + nutrient amended soil and the higher densities of soil fauna (with the exception of mites and protozoa...... were also assessed. Collembolans were found in highest densities in dry heath soil, about 130,000 individuals m-2, more than twice as high as in mesic heath soils. Enchytraeids, diptera larvae and nematodes were also more abundant in the dry heath soil than in mesic heath soils, whereas protozoan...

  6. Soil respiration in northern forests exposed to elevated atmospheric carbon dioxide and ozone.

    Science.gov (United States)

    Pregitzer, Kurt; Loya, Wendy; Kubiske, Mark; Zak, Donald

    2006-06-01

    The aspen free-air CO2 and O3 enrichment (FACTS II-FACE) study in Rhinelander, Wisconsin, USA, is designed to understand the mechanisms by which young northern deciduous forest ecosystems respond to elevated atmospheric carbon dioxide (CO2) and elevated tropospheric ozone (O3) in a replicated, factorial, field experiment. Soil respiration is the second largest flux of carbon (C) in these ecosystems, and the objective of this study was to understand how soil respiration responded to the experimental treatments as these fast-growing stands of pure aspen and birch + aspen approached maximum leaf area. Rates of soil respiration were typically lowest in the elevated O3 treatment. Elevated CO2 significantly stimulated soil respiration (8-26%) compared to the control treatment in both community types over all three growing seasons. In years 6-7 of the experiment, the greatest rates of soil respiration occurred in the interaction treatment (CO2 + O3), and rates of soil respiration were 15-25% greater in this treatment than in the elevated CO2 treatment, depending on year and community type. Two of the treatments, elevated CO2 and elevated CO2 + O3, were fumigated with 13C-depleted CO2, and in these two treatments we used standard isotope mixing models to understand the proportions of new and old C in soil respiration. During the peak of the growing season, C fixed since the initiation of the experiment in 1998 (new C) accounted for 60-80% of total soil respiration. The isotope measurements independently confirmed that more new C was respired from the interaction treatment compared to the elevated CO2 treatment. A period of low soil moisture late in the 2003 growing season resulted in soil respiration with an isotopic signature 4-6 per thousand enriched in 13C compared to sample dates when the percentage soil moisture was higher. In 2004, an extended period of low soil moisture during August and early September, punctuated by a significant rainfall event, resulted in soil

  7. Annual ecosystem respiration budget for a Pinus sylvestris stand in central Siberia

    International Nuclear Information System (INIS)

    Shibistova, O.; Zrazhevskaya, G.; Astrakhantceva, N.; Shijneva, I.; Lloyd, J.; Arneth, A.; Kolle, J.; Knohl, A.; Schmerler, J.

    2002-01-01

    Using a ground-based and an above-canopy eddy covariance system in addition to stem respiration measurements, the annual respiratory fluxes attributable to soil, stems and foliage were determined for a Scots pine (Pinus sylvestris L.) forest growing in central Siberia. Night-time foliar respiration was estimated on the basis of the difference between fluxes measured below and above the canopy and the stem respiration measurements. Comparison of the effects of night-time turbulence on measured CO 2 fluxes showed flux loss above the canopy at low wind speeds, but no such effect was observed for the ground-based eddy system. This suggests that problems with flow homogeneity or flux divergence (both of which would be expected to be greater above the canopy than below) were responsible for above-canopy losses under these conditions. After correcting for this, a strong seasonality in foliar respiration was observed. This was not solely attributable to temperature variations, with intrinsic foliar respiratory capacities being much greater in spring and autumn. The opposite pattern was observed for stem respiration, with the intrinsic respiratory capacity being lower from autumn through early spring. Maximum respiratory activity was observed in early summer. This was not simply associated with a response to higher temperatures but seemed closely linked with cambial activity and the development of new xylem elements. Soil respiration rates exhibited an apparent high sensitivity to temperature, with seasonal data implying a Q 10 of about 7. We interpret this as reflecting covarying changes in soil microbial activity and soil temperatures throughout the snow-free season. Averaged over the two study years (1999 and 2000), the annual respiratory flux was estimated at 38.3 mol C/m 2 /a. Of this 0.61 was attributable to soil respiration, with stem respiration accounting for 0.21 and foliar respiration 0.18

  8. Linking the distribution of carbon isotope ratios in soil carbonates and speleothems to climate conditions in the past: A model for the dependence of respiration rate on soil moisture

    Science.gov (United States)

    Liu, Y.; Ibarra, D. E.; Winnick, M.; Caves Rugenstein, J. K.; Oster, J. L.; Druhan, J. L.

    2017-12-01

    The carbon isotope compositions (δ13C) of atmospheric CO2, C3-origin organic carbon, and limestone epikarst differ substantially, resulting in variable δ13C signatures recorded in secondary soil carbonates and speleothems which represent a mixture of these sources. Even though this signal has been widely used in paleoclimate studies, the extent to which carbonate δ13C is influenced by the dynamic response of organic carbon respiration rates to soil moisture variations has yet to be fully evaluated [1]. Soils that are rewetted after a prolonged drought commonly display a peak in respiration rate followed by relaxation to a lower steady state in both lab incubation experiments and field observations. This transient behavior, known as the Birch effect, has been extensively observed across a broad range of locations and soil types, and may generate more than 50% of the total respired CO2 in some ecosystems [2]. Here, we seek to identify the influence of the Birch effect on carbonate δ13C records based on a moisture-dependent modeling approach. We report compiled respiration rates of soils from the literature and fit these data as a function of soil moisture, before imposing exponential dampening with depth and applying the resulting function in a production-diffusion equation [3]. We then implement a mass balance calculation for the δ13C value of carbonate precipitated from a mixture of atmospheric and respired CO2, including mass-dependent fractionation associated with diffusive transport. Our results offer a novel prediction for depth-resolved carbonate δ13C as a function of soil moisture, and suggest that Birch effect signals may be recorded in soil carbonates and influence the magnitude of carbonate δ13C variations in speleothems. Thus, we illustrate a prediction for the range of carbonate δ13C recorded in terrestrial carbonates and suggest that differences in the range of carbonate δ13C may indicate changes in soil moisture variability, providing a new

  9. A higher chest compression rate may be necessary for metronome-guided cardiopulmonary resuscitation.

    Science.gov (United States)

    Chung, Tae Nyoung; Kim, Sun Wook; You, Je Sung; Cho, Young Soon; Chung, Sung Phil; Park, Incheol

    2012-01-01

    Metronome guidance is a simple and economical feedback system for guiding cardiopulmonary resuscitation (CPR). However, a recent study showed that metronome guidance reduced the depth of chest compression. The results of previous studies suggest that a higher chest compression rate is associated with a better CPR outcome as compared with a lower chest compression rate, irrespective of metronome use. Based on this finding, we hypothesized that a lower chest compression rate promotes a reduction in chest compression depth in the recent study rather than metronome use itself. One minute of chest compression-only CPR was performed following the metronome sound played at 1 of 4 different rates: 80, 100, 120, and 140 ticks/min. Average compression depths (ACDs) and duty cycles were compared using repeated measures analysis of variance, and the values in the absence and presence of metronome guidance were compared. Both the ACD and duty cycle increased when the metronome rate increased (P = .017, metronome rates of 80 and 100 ticks/min were significantly lower than those for the procedures without metronome guidance. The ACD and duty cyle for chest compression increase as the metronome rate increases during metronome-guided CPR. A higher rate of chest compression is necessary for metronome-guided CPR to prevent suboptimal quality of chest compression. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Vastus Lateralis Motor Unit Firing Rate Is Higher in Women With Patellofemoral Pain.

    Science.gov (United States)

    Gallina, Alessio; Hunt, Michael A; Hodges, Paul W; Garland, S Jayne

    2018-05-01

    To compare neural drive, determined from motor unit firing rate, in the vastus medialis and lateralis in women with and without patellofemoral pain. Cross-sectional study. University research laboratory. Women (N=56) 19 to 35 years of age, including 36 with patellofemoral pain and 20 controls. Not applicable. Participants sustained an isometric knee extension contraction at 10% of their maximal voluntary effort for 70 seconds. Motor units (N=414) were identified using high-density surface electromyography. Average firing rate was calculated between 5 and 35 seconds after recruitment for each motor unit. Initial firing rate was the inverse of the first 3 motor unit interspike intervals. In control participants, vastus medialis motor units discharged at higher rates than vastus lateralis motor units (P=.001). This was not observed in women with patellofemoral pain (P=.78) because of a higher discharge rate of vastus lateralis compared with control participants (P=.002). No between-group differences were observed for vastus medialis (P=.93). Similar results were obtained for the initial motor unit firing rate. These findings suggest that women with patellofemoral pain have a higher neural drive to vastus lateralis but not vastus medialis, which may be a contributor of the altered patellar kinematics observed in some studies. The different neural drive may be an adaptation to patellofemoral pain, possibly to compensate for decreased quadriceps force production, or a precursor of patellofemoral pain. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  11. Determination of respirable-sized crystalline silica in different ambient environments in the United Kingdom with a mobile high flow rate sampler utilising porous foams to achieve the required particle size selection

    Science.gov (United States)

    Stacey, Peter; Thorpe, Andrew; Roberts, Paul; Butler, Owen

    2018-06-01

    Inhalation of respirable crystalline silica (RCS) can cause diseases including silicosis and cancer. Levels of RCS close to an emission source are measured but little is known about the wider ambient exposure from industry emissions or natural sources. The aim of this work is to report the RCS concentrations obtained from a variety of ambient environments using a new mobile respirable (PM4) sampler. A mobile battery powered high flow rate (52 L min-1) sampler was developed and evaluated for particulate aerosol sampling employing foams to select the respirable particle size fraction. Sampling was conducted in the United Kingdom at site boundaries surrounding seven urban construction and demolition and five sand quarry sites. These are compared with data from twelve urban aerosol samples and from repeat measurements from a base line study at a single rural site. The 50% particle size penetration (d50) through the foam was 4.3 μm. Over 85% of predict bias values were with ±10% of the respirable convention, which is based on a log normal curve. Results for RCS from all construction and quarry activities are generally low with a 95 th percentile of 11 μg m-3. Eighty percent of results were less than the health benchmark value of 3 μg m-3 used in some states in America for ambient concentrations. The power cutting of brick and the largest demolition activities gave the highest construction levels. Measured urban background RCS levels were typically below 0.3 μg m-3 and the median RCS level, at a rural background location, was 0.02 μg m-3. These reported ambient RCS concentrations may provide useful baseline values to assess the wider impact of fugitive, RCS containing, dust emissions into the wider environment.

  12. Choosing the right respirator

    International Nuclear Information System (INIS)

    Bidwell, J.

    1997-01-01

    Selecting respirators to help protect workers from airborne contaminants can be a confusing process. The consequences of selecting the incorrect respirator can be intimidating, and worker safety and health may be dramatically and irreparably affected if an inappropriate respirator is chosen. When used in the workplace, a formal respiratory protection program must be established covering the basic requirements outlined in the OSHA Respiratory Protection Standard (29 CFR 1910.134). Education and training must be properly emphasized and conducted periodically. Maintenance, cleaning, and storage programs must be established and routinely followed for reusable respirators. The process of establishing a respiratory protection program can be broken down into four basic steps: Identify respiratory hazards and concentrations; understand the contaminants effects on workers' health; select appropriate respiratory protection; and train in proper respirator use and maintenance. These four steps are the foundation for establishing a basic respirator protection program. Be sure to consult state and federal OSHA requirements to ensure that the program complies. Leading industrial respirator manufacturers should be able to assist with on-site training and education in this four-step process, in addition to helping employers train their workers and conduct respirator fit testing

  13. Soil respiration fluxes in a temperate mixed forest: seasonality and temperature sensitivities differ among microbial and root-rhizosphere respiration.

    Science.gov (United States)

    Ruehr, Nadine K; Buchmann, Nina

    2010-02-01

    Although soil respiration, a major CO(2) flux in terrestrial ecosystems, is known to be highly variable with time, the response of its component fluxes to temperature and phenology is less clear. Therefore, we partitioned soil respiration (SR) into microbial (MR) and root-rhizosphere respiration (RR) using small root exclusion treatments in a mixed mountain forest in Switzerland. In addition, fine root respiration (FRR) was determined with measurements of excised roots. RR and FRR were strongly related to each other (R(2) = 0.92, n = 7), with RR contributing about 46% and FRR about 32% to total SR. RR rates increased more strongly with temperature (Q(10) = 3.2) than MR rates (Q(10) = 2.3). Since the contribution of RR to SR was found to be higher during growing (50%) than during dormant periods (40%), we separated the 2-year data set into phenophases. During the growing period of 2007, the temperature sensitivity of RR (Q(10) = 2.5, R(2) = 0.62) was similar to that of MR (Q(10) = 2.2, R(2) = 0.57). However, during the dormant period of 2006/2007, RR was not related to soil temperature (R(2) = 0.44, n.s.), in contrast to MR (Q(10) = 7.2; R(2) = 0.92). To better understand the influence of plant activity on root respiration, we related RR and FRR rates to photosynthetic active radiation (both R(2) = 0.67, n = 7, P = 0.025), suggesting increased root respiration rates during times with high photosynthesis. During foliage green-up in spring 2008, i.e., from bud break to full leaf expansion, RR increased by a factor of 5, while soil temperature increased only by about 5 degrees C, leading to an extraordinary high Q(10) of 10.6; meanwhile, the contribution of RR to SR increased from 29 to 47%. This clearly shows that root respiration and its apparent temperature sensitivity highly depend on plant phenology and thus on canopy assimilation and carbon allocation belowground.

  14. BOREAS TE-5 Soil Respiration Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Ehleriinger, Jim; Brooks, J. Renee; Flanagan, Larry

    2000-01-01

    The BOREAS TE-5 team collected measurements in the NSA and SSA on gas exchange, gas composition, and tree growth. Soil respiration data were collected from 26-May-94 to 07-Sep-94 in the BOREAS NSA and SSA to compare the soil respiration rates in different forest sites using a LI-COR 6200 soil respiration chamber (model 6299). The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distrobuted Activity Archive Center (DAAC).

  15. Does the Economic Crisis Have an Influence on the Higher Education Dropout Rate?

    Science.gov (United States)

    Leão Fernandes, Graça; Chagas Lopes, Margarida

    2016-01-01

    This research aims to identify the effects of the economic crisis on higher education (HE) dropout rates at Lisbon School of Economics and Management (ISEG)--Universidade de Lisboa, after having controlled for individual characteristics, family background, High School and HE trajectories. Our main hypothesis is that the economic crisis induces…

  16. Will ageing lead to a higher real exchange rate for the Netherlands?

    NARCIS (Netherlands)

    van Ewijk, C.; Volkerink, M.

    2012-01-01

    Long term projections for the Netherlands indicate that demand for nontradables—e.g. health care services—will increase relative to supply due to population ageing. If this leads to higher future real exchanges rates this will erode the return of the savings currently made to prepare for ageing.

  17. Will ageing lead to a higher real exchange rate for the Netherlands?

    NARCIS (Netherlands)

    van Ewijk, C.; Volkerink, M.

    2011-01-01

    Long-term projections for the Netherlands indicate that demand for nontradables - e.g. health care services - will increase relative to supply due to population ageing. If this leads to higher future real exchanges rates this will erode the return of the savings currently made to prepare for ageing.

  18. Why do younger women have higher breast cancer recurrence rates after breast-conserving surgery?

    International Nuclear Information System (INIS)

    Nishimura, Reiki; Matsuda, Masakazu; Miyayama, Haruhiko; Okazaki, Shinji; Kai, Chiharu; Ozaki, N.

    2003-01-01

    Preventing breast cancer recurrence after breast-conserving surgery is an important issue. The main factors contributing to such recurrence are positive margins, absence of radiotherapy and young age. To investigate the clinical significance of age in breast-conserving surgery, we examined the relationship between clinicopathological findings or outcome and age, especially young age. The cases were divided into three groups by age; 35 years old or less, 36-50y.o. and 51y.o. or higher. Between April 1989 and March 2003, 743 patients were treated with breast-conserving surgery. There were 49 patients aged 35 years old or less (6.6%). Younger age significantly correlated with positive surgical margin, lymph node metastases, higher proliferative activity, negative estrogen receptor (ER) or progesterone receptor (PgR), larger tumor size, and shorter nipple-tumor distances. Although younger patients had a higher recurrence rate irrespective of radiotherapy, margin status had an impact on recurrence rate. Thus, the reason young age was a significant factor for breast recurrence after breast-conserving surgery was that young patients frequently had numerous risk factors such as positive margin, higher proliferative activity, positive nodes, negative ER/PgR and larger tumor. However, negative surgical margins could reduce recurrence rates even in young women. These results suggest that more suitable criteria and strategies may be needed for young patients with breast cancer. (author)

  19. Soil Respiration of Three Mangrove Forests on Sanibel Island, Florida

    Science.gov (United States)

    Cartwright, F.; Bovard, B. D.

    2011-12-01

    Carbon cycling studies conducted in mangrove forests have typically focused on aboveground processes. Our understanding of carbon storage in these systems is therefore limited by the lack information on belowground processes such as fine root production and soil respiration. To our knowledge there exist no studies investigating temporal patterns in and environmental controls on soil respiration in multiple types of mangrove ecosystems concurrently. This study is part of a larger study on carbon storage in three mangrove forests on Sanibel Island, Florida. Here we report on eight months of soil respiration data within these forests that will ultimately be incorporated into an annual carbon budget for each habitat type. Soil respiration was monitored in the following three mangrove habitat types: a fringe mangrove forest dominated by Rhizophora mangle, a basin mangrove forest dominated by Avicennia germinans, and a higher elevation forest comprised of a mix of Avicennia germinans and Laguncularia racemosa, and non-woody salt marsh species. Beginning in June of 2010, we measured soil emissions of carbon dioxide at 5 random locations within three-100 m2 plots within each habitat type. Sampling was performed at monthly intervals and conducted over the course of three days. For each day, one plot from each habitat type was measured. In addition to soil respiration, soil temperature, salinity and gravimetric moisture content were also measured. Our data indicate the Black mangrove forest, dominated by Avicennia germinans, experiences the highest rates of soil respiration with a mean rate of 4.61 ± 0.60 μmol CO2 m-2 s-1. The mixed mangrove and salt marsh habitat has the lowest soil carbon emission rates with a mean of 2.78 ± 0.40 μmol CO2 m-2 s-1. Soil carbon effluxes appear to peak in the early part of the wet season around May to June and are lower and relatively constant the remainder of the year. Our data also suggest there are important but brief periods where

  20. Respiration in Aquatic Insects.

    Science.gov (United States)

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  1. How much work is expended for respiration?

    Science.gov (United States)

    Johnson, A T

    1993-01-01

    The rate of work expended to move air in the respiratory system has been determined for five different airflow waveshapes, a non-linear respiratory model and five exercise levels. As expected, the rectangular waveshape was the most efficient. Model conditions were then changed one a time: (i) starting lung volume was allowed to vary, (ii) exhalation flow limitation was added, (iii) respiration was considered to be a metabolic burden determining part of the ventilation requirement and (iv) a respirator mask was added. Although there is no direct work advantage to varying initial lung volume, such volume changes appear to be dictated by the asymmetry of lung recoil pressure about the lung relaxation volume; allowing the work of respiration to become a metabolic burden clearly shows why respiratory waveforms change from rest to exercise; and, adding a respirator imposes a severe respiratory burden on the wearer engaging in moderate, heavy and very heavy exercise.

  2. Calm Merino ewes have a higher ovulation rate and more multiple pregnancies than nervous ewes.

    Science.gov (United States)

    van Lier, E; Hart, K W; Viñoles, C; Paganoni, B; Blache, D

    2017-07-01

    In 1990, two selection lines of Merino sheep were established for low and high behavioural reactivity (calm and nervous temperament) at the University of Western Australia. Breeding records consistently showed that calm ewes weaned 10% to 19% more lambs than the nervous ewes. We hypothesise that calm ewes could have a higher ovulation rate than nervous ewes and/or calm ewes could have a lower rate of embryo mortality than nervous ewes. We tested these hypotheses by comparing the ovulation rate and the rate of embryo mortality between the calm and nervous lines before and after synchronisation and artificial insemination. Merino ewes from the temperament selection lines (calm, n=100; nervous, n=100) were synchronised (early breeding season) for artificial insemination (day 0) (intravaginal sponges containing fluogestone acetate and eCG immediately after sponge withdrawal). On day-17 and 11 ovarian cyclicity and corpora lutea, and on days 30 and 74 pregnancies and embryos/foetuses were determined by ultrasound. Progesterone, insulin and leptin concentrations were determined in blood plasma samples from days 5, 12 and 17. Ovarian cyclicity before and after oestrus synchronisation did not differ between the lines, but ovulation rate did (day-17: calm 1.63; nervous 1.26; Pewes was higher than on day-17. Loss of embryos by day 30 was high (calm: 71/150; nervous: 68/130); but nervous ewes had a lower proportion (15/47) of multiple pregnancies compared with calm ewes (30/46; Pewes had higher insulin (32.0 pmol/l±1.17 SEM; P=0.013) and lower leptin (1.18 μg/l±0.04 SEM; P=0.002) concentrations than calm ewes (insulin: 27.8 pmol/l±1.17 SEM; leptin: 1.35 μg/l±0.04 SEM). The differences in reproductive outcomes between the calm and nervous ewes were mainly due to a higher ovulation rate in calm ewes. We suggest that reproduction in nervous ewes is compromised by factors leading up to ovulation and conception, or the uterine environment during early pregnancy, that reflect

  3. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Directory of Open Access Journals (Sweden)

    Or Sperling

    Full Text Available Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq. cm(-3 yr(-1 on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  4. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    Science.gov (United States)

    Sperling, Or; Earles, J Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A

    2015-01-01

    Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq.) cm(-3) yr(-1) on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics.

  5. Splenectomy is associated with higher infection and pneumonia rates among trauma laparotomy patients.

    Science.gov (United States)

    Fair, Kelly A; Connelly, Christopher R; Hart, Kyle D; Schreiber, Martin A; Watters, Jennifer M

    2017-05-01

    Splenectomy increases lifetime risk of thromboembolism (VTE) and is associated with long-term infectious complications, primarily, overwhelming post-splenectomy infection (OPSI). Our objective was to evaluate risk of VTE and infection at index hospitalization post-splenectomy. Retrospective review of all patients who received a laparotomy in the NTDB. Propensity score matching for splenectomy was performed, based on ISS, abdominal abbreviated injury score >3, GCS, sex and mechanism. Major complications, VTE, and infection rates were compared. Multiple logistic regression models were utilized to evaluate splenectomy-associated complications. 93,221 laparotomies were performed and 17% underwent splenectomy. Multiple logistic regression models did not demonstrate an association between splenectomy and major complications (OR 0.96, 95% CI 0.91-1.03, p = 0.25) or VTE (OR 1.05, 95% CI 0.96-1.14, p = 0.33). Splenectomy was independently associated with infection (OR 1.07, 95% CI 1.00-1.14, p = 0.045). Subgroup analysis of patients with infection demonstrated that splenectomy was most strongly associated with pneumonia (OR 1.41, 95% CI 1.26-1.57, p Splenectomy is not associated with higher overall complication or VTE rates during index hospitalization. However, splenectomy is associated with a higher rate of pneumonia. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. With age a lower individual breathing reserve is associated with a higher maximal heart rate.

    Science.gov (United States)

    Burtscher, Martin; Gatterer, Hannes; Faulhaber, Martin; Burtscher, Johannes

    2018-01-01

    Maximal heart rate (HRmax) is linearly declining with increasing age. Regular exercise training is supposed to partly prevent this decline, whereas sex and habitual physical activity do not. High exercise capacity is associated with a high cardiac output (HR x stroke volume) and high ventilatory requirements. Due to the close cardiorespiratory coupling, we hypothesized that the individual ventilatory response to maximal exercise might be associated with the age-related HRmax. Retrospective analyses have been conducted on the results of 129 consecutively performed routine cardiopulmonary exercise tests. The study sample comprised healthy subjects of both sexes of a broad range of age (20-86 years). Maximal values of power output, minute ventilation, oxygen uptake and heart rate were assessed by the use of incremental cycle spiroergometry. Linear multivariate regression analysis revealed that in addition to age the individual breathing reserve at maximal exercise was independently predictive for HRmax. A lower breathing reserve due to a high ventilatory demand and/or a low ventilatory capacity, which is more pronounced at a higher age, was associated with higher HRmax. Age explained the observed variance in HRmax by 72% and was improved to 83% when the variable "breathing reserve" was entered. The presented findings indicate an independent association between the breathing reserve at maximal exercise and maximal heart rate, i.e. a low individual breathing reserve is associated with a higher age-related HRmax. A deeper understanding of this association has to be investigated in a more physiological scenario. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. New system for higher recovery rate of water borne Cryptosporidium oocysts and Giardia cysts

    DEFF Research Database (Denmark)

    Al-Sabi, Mohammad Nafi Solaiman; Gad, Jens; Klinting, Mette

    2012-01-01

    Background: The two most common water borne pathogenic protozoa, Cryptosporidium and Giardia, cause diarrhea worldwide. Detecting these parasites in water samples depends on effective parasite recovery from the water matrix. The reported low recovery rates of the currently used filter methods...... motivate the development of systems with higher recovery rates. Materials and methods: Five replicates of IMS purified Cryptosporidium oocysts and Giardia cysts (N=2x103) were injected into a specially coated filter unit with a carefully chosen pore size. Following filtration, sonication was performed...... were 85% were recorded when the filter was sonicated. Sonication usually affects parasite viability but could be tuned into a useful tool for enhanced backwash collection of parasites using a specially constructed filter unit and a sonication protocol. The filtration...

  8. Why the EU-15 Maintains Higher CIT Rates than the New Member States?

    Directory of Open Access Journals (Sweden)

    Karpowicz Andrzej

    2014-11-01

    Full Text Available The European Union is not a homogenous area. This lack of homogeneity extends to taxes, which vary across jurisdictions. On average, Western Europe imposes significantly higher taxes on capital than New Member States, which joined the Community in 2004 and 2007. Often this fact is simply taken for granted. However, there are several arguments that can explain this variance. Although several of these arguments are well known and have been researched, they have not been assessed in combination, or used in a comparative analysis of corporate income tax (CIT rates between EU member states. Because of interest in harmonizing CIT throughout the EU, the roots of divergent CIT is of particular and timely value. Therefore, this article we attempts to demonstrate the differences in CIT rates in the EU-15 and New Member States. In so doing the general characteristics of these country grouping is identified, and then discussed in the context of the taxation theory.

  9. Higher order constraints on the Higgs production rate from fixed-target DIS data

    International Nuclear Information System (INIS)

    Alekhin, S.; Bluemlein, J.; Moch, S.

    2011-01-01

    The constraints of fixed-target DIS data in fits of parton distributions including QCD corrections to next-to-next-to leading order are studied. We point out a potential problem in the analysis of the NMC data which can lead to inconsistencies in the extracted value for α s (M Z ) and the gluon distribution at higher orders in QCD. The implications for predictions of rates for Standard Model Higgs boson production at hadron colliders are investigated. We conclude that the current range of excluded Higgs boson masses at the Tevatron appears to be much too large. (orig.)

  10. Strain rate effects in nuclear steels at room and higher temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Solomos, G. E-mail: george.solomos@jrc.it; Albertini, C.; Labibes, K.; Pizzinato, V.; Viaccoz, B

    2004-04-01

    An investigation of strain rate, temperature and size effects in three nuclear steels has been conducted. The materials are: ferritic steel 20MnMoNi55 (vessel head), austenitic steel X6CrNiNb1810 (upper internal structure), and ferritic steel 26NiCrMo146 (bolting). Smooth cylindrical tensile specimens of three sizes have been tested at strain rates from 0.001 to 300 s{sup -1}, at room and elevated temperatures (400-600 deg. C). Full stress-strain diagrams have been obtained, and additional parameters have been calculated based on them. The results demonstrate a clear influence of temperature, which amounts into reducing substantially mechanical strengths with respect to RT conditions. The effect of strain rate is also shown. It is observed that at RT the strain rate effect causes up shifting of the flow stress curves, whereas at the higher temperatures a mild downshifting of the flow curves is manifested. Size effect tendencies have also been observed. Some implications when assessing the pressure vessel structural integrity under severe accident conditions are considered.

  11. Coordinate regulation of cytochrome and alternative pathway respiration in tobacco.

    Science.gov (United States)

    Vanlerberghe, G C; McIntosh, L

    1992-12-01

    In suspension cells of NT1 tobacco (Nicotiana tabacum L. cv bright yellow), inhibition of the cytochrome pathway of respiration with antimycin A induced a large increase in the capacity of the alternative pathway over a period of approximately 12 h, as confirmed in both whole cells and isolated mitochondria. The increase in alternative pathway capacity required de novo RNA and protein synthesis and correlated closely with the increase of a 35-kD alternative oxidase protein. When the cytochrome pathway of intact cells was inhibited by antimycin A, respiration proceeded exclusively through the alternative pathway, reached rates significantly higher than before antimycin A addition, and was not stimulated by p-trifluoromethoxycarbonylcyanide (FCCP). When inhibition of the cytochrome pathway was relieved, alternative pathway capacity and the level of the 35-kD alternative oxidase protein declined. Respiration rate also declined and could once again be stimulated by FCCP. These observations show that the capacities of the mitochondrial electron transport pathways can be regulated in a coordinate fashion.

  12. Higher Growth Rate of Branch Duct Intraductal Papillary Mucinous Neoplasms Associates With Worrisome Features.

    Science.gov (United States)

    Kolb, Jennifer M; Argiriadi, Pamela; Lee, Karen; Liu, Xiaoyu; Bagiella, Emilia; Lucas, Aimee L; Kim, Michelle Kang; Kumta, Nikhil A; Nagula, Satish; Sarpel, Umut; DiMaio, Christopher J

    2018-03-11

    or invasive cancers. BD-IPMNs that developed worrisome features were associated with a significantly higher rate of growth than lesions with low-risk features. Low risk BD-IPMNs that grow more than 2.5 mm/year might require surveillance. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  13. Soil Respiration under Different Land Uses in Eastern China

    Science.gov (United States)

    Fan, Li-Chao; Yang, Ming-Zhen; Han, Wen-Yan

    2015-01-01

    Land-use change has a crucial influence on soil respiration, which further affects soil nutrient availability and carbon stock. We monitored soil respiration rates under different land-use types (tea gardens with three production levels, adjacent woodland, and a vegetable field) in Eastern China at weekly intervals over a year using the dynamic closed chamber method. The relationship between soil respiration and environmental factors was also evaluated. The soil respiration rate exhibited a remarkable single peak that was highest in July/August and lowest in January. The annual cumulative respiration flux increased by 25.6% and 20.9% in the tea garden with high production (HP) and the vegetable field (VF), respectively, relative to woodland (WL). However, no significant differences were observed between tea gardens with medium production (MP), low production (LP), WL, and VF. Soil respiration rates were significantly and positively correlated with organic carbon, total nitrogen, and available phosphorous content. Each site displayed a significant exponential relationship between soil respiration and soil temperature measured at 5 cm depth, which explained 84–98% of the variation in soil respiration. The model with a combination of soil temperature and moisture was better at predicting the temporal variation of soil respiration rate than the single temperature model for all sites. Q10 was 2.40, 2.00, and 1.86–1.98 for VF, WL, and tea gardens, respectively, indicating that converting WL to VF increased and converting to tea gardens decreased the sensitivity of soil respiration to temperature. The equation of the multiple linear regression showed that identical factors, including soil organic carbon (SOC), soil water content (SWC), pH, and water soluble aluminum (WSAl), drove the changes in soil respiration and Q10 after conversion of land use. Temporal variations of soil respiration were mainly controlled by soil temperature, whereas spatial variations were

  14. Plant species richness regulates soil respiration through changes in productivity.

    Science.gov (United States)

    Dias, André Tavares Corrêa; van Ruijven, Jasper; Berendse, Frank

    2010-07-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration.

  15. Do traits of invasive species influence decomposition and soil respiration of disturbed ecosystems?

    Science.gov (United States)

    Wells, A. J.; Balster, N. J.

    2009-12-01

    Large-scale landscape disturbances typically alter the terrestrial carbon cycle leading to shifts in pools of soil carbon. Restoration of disturbed landscapes with prairie vegetation has thus been practiced with the intent of increasing carbon accrual in soils. However, since disturbed soils are prone to invasion by non-native invasive species, many ecological restorations have resulted in unexpected outcomes, which may be explained by differences in plant traits such as tissue quality and biomass allocation. Typically, the tissue of invasive species has lower C:N ratios relative to native species, and consequently, faster decomposition rates, which potentially can alter the balance in soil carbon. The primary objective of this research was to compare the effects of native prairie species versus non-native invasive species on the carbon cycling within a novel environment: a recently dewatered basin in southwestern Wisconsin following dam removal. We hypothesized that a higher invasive to native species ratio would result in faster litter decomposition and a higher rate of soil respiration. To test this hypothesis, we seeded newly exposed sediments with native prairie seeds in 2005, annually collected aboveground plant biomass (by species per plot), calculated decomposition rate of native and invasive litter (underneath both canopy types), and measured soil respiration during the growing season of 2009. After four years of seeding, the aboveground biomass of the native vegetation has increased significantly (p invasive species biomass has decreased from 459 to 296 g m-2. Senesced tissue from mixed native species had a higher C:N ratio, 27:1 (43% C: 1.6% N), than tissue from mixed invasive species, 24:1 (35% C: 1.5% N). However, after 7 months, we found that the rate of decomposition depended on both litter type and plant canopy type (p invasive plant tissue had a slightly faster decomposition rate than the native litter and this rate was elevated under invasive

  16. Rabies Vaccination: Higher Failure Rates in Imported Dogs than in those Vaccinated in Italy.

    Science.gov (United States)

    Rota Nodari, E; Alonso, S; Mancin, M; De Nardi, M; Hudson-Cooke, S; Veggiato, C; Cattoli, G; De Benedictis, P

    2017-03-01

    The current European Union (EU) legislation decrees that pets entering the EU from a rabies-infected third country have to obtain a satisfactory virus-neutralizing antibody level, while those moving within the EU require only rabies vaccination as the risk of moving a rabid pet within the EU is considered negligible. A number of factors driving individual variations in dog vaccine response have been previously reported, including a high rate of vaccine failure in puppies, especially those subject to commercial transport. A total of 21 001 observations collected from dogs (2006-2012) vaccinated in compliance with the current EU regulations were statistically analysed to assess the effect of different risk factors related to rabies vaccine efficacy. Within this framework, we were able to compare the vaccination failure rate in a group of dogs entering the Italian border from EU and non-EU countries to those vaccinated in Italy prior to international travel. Our analysis identified that cross-breeds and two breed categories showed high vaccine success rates, while Beagles and Boxers were the least likely to show a successful response to vaccination (88.82% and 90.32%, respectively). Our analysis revealed diverse performances among the commercially available vaccines, in terms of serological peak windows, and marked differences according to geographical area. Of note, we found a higher vaccine failure rate in imported dogs (13.15%) than in those vaccinated in Italy (5.89%). Our findings suggest that the choice of vaccine may influence the likelihood of an animal achieving a protective serological level and that time from vaccination to sampling should be considered when interpreting serological results. A higher vaccine failure in imported compared to Italian dogs highlights the key role that border controls still have in assessing the full compliance of pet movements with EU legislation to minimize the risk of rabies being reintroduced into a disease-free area.

  17. Does higher income inequality adversely influence infant mortality rates? Reconciling descriptive patterns and recent research findings.

    Science.gov (United States)

    Siddiqi, Arjumand; Jones, Marcella K; Erwin, Paul Campbell

    2015-04-01

    As the struggle continues to explain the relatively high rates of infant mortality (IMR) exhibited in the United States, a renewed emphasis is being placed on the role of possible 'contextual' determinants. Cross-sectional and short time-series studies have found that higher income inequality is associated with higher IMR at the state level. Yet, descriptively, the longer-term trends in income inequality and in IMR seem to call such results into question. To assess whether, over the period 1990-2007, state-level income inequality is associated with state-level IMR; to examine whether the overall effect of income inequality on IMR over this period varies by state; to test whether the association between income inequality and IMR varies across this time period. IMR data--number of deaths per 1000 live births in a given state and year--were obtained from the U.S. Centers for Disease Control Wonder database. Income inequality was measured using the Gini coefficient, which varies from zero (complete equality) to 100 (complete inequality). Covariates included state-level poverty rate, median income, and proportion of high school graduates. Fixed and random effects regressions were conducted to test hypotheses. Fixed effects models suggested that, overall, during the period 1990-2007, income inequality was inversely associated with IMR (β = -0.07, SE (0.01)). Random effects models suggested that when the relationship was allowed to vary at the state-level, it remained inverse (β = -0.05, SE (0.01)). However, an interaction between income inequality and time suggested that, as time increased, the effect of income inequality had an increasingly positive association with total IMR (β = 0.009, SE (0.002)). The influence of state income inequality on IMR is dependent on time, which may proxy for time-dependent aspects of societal context. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Partitioning of ecosystem respiration in a beech forest

    DEFF Research Database (Denmark)

    Brændholt, Andreas; Ibrom, Andreas; Larsen, Klaus Steenberg

    2018-01-01

    Terrestrial ecosystem respiration (Reco) represents a major component of the global carbon cycle. It consists of many sub-components, such as aboveground plant respiration and belowground root and microbial respiration, each of which may respond differently to abiotic factors, and thus to global...... of Reco in a temperate beech forest at diel, seasonal and annual time scales. Reco was measured by eddy covariance while respiration rates from soil, tree stems and isolated coarse tree roots were measured bi-hourly by an automated closed-chamber system. Soil respiration (Rsoil) was measured in intact...... plots, and heterotrophic Rsoil was measured in trenched plots. Tree stem (Rstem) and coarse root (Rroot) respiration were measured by custom made closed-chambers. We found that the contribution of Rstem to total Reco varied across the year, by only accounting for 6% of Reco during winter and 16% during...

  19. Higher resting heart rate variability predicts skill in expressing some emotions.

    Science.gov (United States)

    Tuck, Natalie L; Grant, Rosemary C I; Sollers, John J; Booth, Roger J; Consedine, Nathan S

    2016-12-01

    Vagally mediated heart rate variability (vmHRV) is a measure of cardiac vagal tone, and is widely viewed as a physiological index of the capacity to regulate emotions. However, studies have not directly tested whether vmHRV is associated with the ability to facially express emotions. In extending prior work, the current report tested links between resting vmHRV and the objectively assessed ability to facially express emotions, hypothesizing that higher vmHRV would predict greater expressive skill. Eighty healthy women completed self-reported measures, before attending a laboratory session in which vmHRV and the ability to express six emotions in the face were assessed. A repeated measures analysis of variance revealed a marginal main effect for vmHRV on skill overall; individuals with higher resting vmHRV were only better able to deliberately facially express anger and interest. Findings suggest that differences in resting vmHRV are associated with the objectively assessed ability to facially express some, but not all, emotions, with potential implications for health and well-being. © 2016 Society for Psychophysiological Research.

  20. Invasive acacias experience higher ant seed removal rates at the invasion edges

    Directory of Open Access Journals (Sweden)

    D. Montesinos

    2012-06-01

    Full Text Available Seed dispersal is a key process for the invasion of new areas by exotic species. Introduced plants often take advantage of native generalist dispersers. Australian acacias are primarily dispersed by ants in their native range and produce seeds bearing a protein and lipid rich reward for ant mutualists (elaiosome. Nevertheless, the role of myrmecochory in the expansion of Australian acacias in European invaded areas is still not clear. We selected one European population of Acacia dealbata and another of A. longifolia and offered elaiosome-bearing and elaiosome-removed seeds to local ant communities. For each species, seeds were offered both in high-density acacia stands and in low-density invasion edges. For both acacia species, seed removal was significantly higher at the low-density edges. For A. longifolia, manual elimination of elaiosomes reduced the chance of seed removal by 80% in the low-density edges, whereas it made no difference on the high-density stands. For A. dealbata, the absence of elaiosome reduced seed removal rate by 52%, independently of the acacia density. Our data suggests that invasive acacias have found effective ant seed dispersers in Europe and that the importance of such dispersers is higher at the invasion edges.

  1. Optimizing rate of nitrogen application for higher growth and yield of wheat (triticum aestivum l.) cultivars

    International Nuclear Information System (INIS)

    Maqsood, M.; Shehzad, M.A.; Asim, A.; Ahmad, W.

    2012-01-01

    In order to optimize the nitrogen rates in three wheat (Triticum aestivum L.) cultivars for obtaining higher grain yield, a split plot experiment based on Randomized Complete Block Design with three replicates was conducted in the research field of University of Agriculture, Faisalabad during Rabi season 2006-07. Among treatments nitrogen levels (N0= 0, N/sub 1/= 50, N2= 100, N3= 150 kg ha/sup -1/) in main while wheat cultivars (V1= Punjnad-I, V/sub 2/= Fareed-2006, V3=Uqab-2000) were allocated in sub plots during the course of growing season. Traits as plant height, fertile tillers, spike length, spikelets spike-1, grains spike-1, 1000-grain weight, straw yield, grain yield and harvest index (HI) were significantly (P=0.05) affected by treatment combinations. Maximum grain yield was obtained by V3 (Uqab-2000) cultivar when treated with N3 (150 kg ha/sup -1/) fertilizer level. Also, results showed that with increasing nitrogen rates, wheat yield increases significantly up to a level of significance (P=0.05). Increasing nitrogen levels led to significantly increase in plant height (101.81 cm), spike bearing tillers (495.77), grains spike/sup -1/ (61.45), straw yield (8.60 t ha/sup -1/) and harvest index (36.17%) of V3 (Uqab-2000). In all traits except germination count, V3 (Uqab-2000) was found to be superior. (author)

  2. Effect of additives for higher removal rate in lithium niobate chemical mechanical planarization

    International Nuclear Information System (INIS)

    Jeong, Sukhoon; Lee, Hyunseop; Cho, Hanchul; Lee, Sangjik; Kim, Hyoungjae; Kim, Sungryul; Park, Jaehong; Jeong, Haedo

    2010-01-01

    High roughness and a greater number of defects were created by lithium niobate (LN; LiNbO 3 ) processes such as traditional grinding and mechanical polishing (MP), should be decreased for manufacturing LN device. Therefore, an alternative process for gaining defect-free and smooth surface is needed. Chemical mechanical planarization (CMP) is suitable method in the LN process because it uses a combination approach consisting of chemical and mechanical effects. First of all, we investigated the LN CMP process using commercial slurry by changing various process conditions such as down pressure and relative velocity. However, the LN CMP process time using commercial slurry was long to gain a smooth surface because of lower material removal rate (MRR). So, to improve the material removal rate (MRR), the effects of additives such as oxidizer (hydrogen peroxide; H 2 O 2 ) and complexing agent (citric acid; C 6 H 8 O 7 ) in a potassium hydroxide (KOH) based slurry, were investigated. The manufactured slurry consisting of H 2 O 2 -citric acid in the KOH based slurry shows that the MRR of the H 2 O 2 at 2 wt% and the citric acid at 0.06 M was higher than the MRR for other conditions.

  3. Higher Rates of DZ Twinning in a Twenty-First Century Birth Cohort.

    Science.gov (United States)

    Rhea, Sally Ann; Corley, Robin P; Heath, Andrew C; Iacono, William G; Neale, Michael C; Hewitt, John K

    2017-09-01

    The Colorado Twin Registry is a population based registry initiated in 1984 with the involvement of the Colorado Department of Health, Division of Vital Statistics. Recruitment includes birth cohorts several years prior to 1984 and all subsequent years. As part of a recent evaluation of Colorado birth records for the years 2006 through 2008 we became aware of a shifting trend in the proportion of MZ and DZ twins in the Colorado population. Historically (Bulmer 1970 The biology of twinning in man, Clarendon, Oxford) we have expected a 1/3, 1/3, 1/3 ratio of MZ, same-sex DZ and opposite sex DZ twins in Caucasian populations. An excess of MZ pairs in most studies was assumed to be due to selection bias. Somewhat more recently, Hur et al.(1995 Behav Genet 25, 337-340) provided evidence that the DZ twinning rate was falling and that therefore selection bias was not the reason for higher MZ enrollment in most twin studies. They suggested that twin researchers might consider strategies to over-enroll DZ pairs to maximize statistical power. In contrast, we now find that of the 3217 twin births in Colorado from 2006 to 2008 with identified sex information the MZ rate is estimated at only 22%, and we have corroborating reports from other states of similar estimates. These were calculated applying Weinberg's rule which assumes an equal birth rate for same sex and opposite sex DZ pairs so that the proportion of MZ in a sample is the proportion of same sex (MM + FF) minus the proportion of opposite-sex (MF, FM). We explore factors, such as an increase in the proportion of non-Caucasian parents and an increase in average maternal age, which may contribute to this shift.

  4. Temperature Dependence of Respiration in Larvae and Adult Colonies of the Corals Acropora tenuis and Pocillopora damicornis

    Directory of Open Access Journals (Sweden)

    Dwi Haryanti

    2015-06-01

    Full Text Available Although algal symbionts can become a source of reactive oxygen species under stressful conditions, symbiotic planulae of the coral Pocillopora damicornis are highly tolerant to thermal stress compared with non-symbiotic planulae of Acropora tenuis. As a first step to understand how P. damicornis planulae attain high stress tolerance, we compared the respiration rate and temperature dependence between symbiotic planulae of P. damicornis and non-symbiotic planulae of A. tenuis, as well as between larvae and adult branches within each species. Larvae and adult branches of both species had similar temperature dependency of respiration rate, with the temperature coefficient (Q10 values of about 2. Planula larvae of P. damicornis had a significantly lower respiration rate than that of A. tenuis larvae at 25–30 °C, but not at 32 °C, whereas adult branches of P. damicornis had a significantly higher respiration rate than that of A. tenuis branches at all temperatures. Thus, P. damicornis larvae appear to be capable of reducing their respiration rate to a greater extent than A. tenuis larvae, which could partly explain why P. damicornis larvae had high survivorship under thermal stress, although other antioxidant or photoprotective mechanisms should be investigated in the future.

  5. Amplification and dampening of soil respiration by changes in temperature variability

    Directory of Open Access Journals (Sweden)

    C. A. Sierra

    2011-04-01

    Full Text Available Accelerated release of carbon from soils is one of the most important feedbacks related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature variability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature. Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long-term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen the release of carbon through soil respiration as climate regimes change. These effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.

  6. Soil respiration in tropical seasonal rain forest in Xishuangbanna, SW China

    Institute of Scientific and Technical Information of China (English)

    SHA; Liqing; ZHENG; Zheng; TANG; Jianwei; WANG; Yinghong

    2005-01-01

    With the static opaque chamber and gas chromatography technique, from January 2003 to January 2004 soil respiration was investigated in a tropical seasonal rain forest in Xishuangbanna, SW China. In this study three treatments were applied, each with three replicates: A (bare soil), B (soil+litter), and C (soil+litter+seedling). The results showed that soil respiration varied seasonally, low from December 2003 to February 2004, and high from June to July 2004. The annual average values of CO2 efflux from soil respiration differed among the treatments at 1% level, with the rank of C (14642 mgCO2· m-2. h-1)>B (12807 mgCO2· m-2. h-1)>A (9532 mgCO2· m-2. h-1). Diurnal variation in soil respiration was not apparent due to little diurnal temperate change in Xishuangbanna. There was a parabola relationship between soil respiration and soil moisture at 1% level. Soil respiration rates were higher when soil moisture ranged from 35% to 45%. There was an exponential relationship between soil respiration and soil temperature (at a depth of 5cm in mineral soil) at 1% level. The calculated Q1o values in this study,ranging from 2.03 to 2.36, were very near to those of tropical soil reported. The CO2 efflux in 2003was 5.34 kgCO2· m-2. a-1 from soil plus litter plus seedling, of them 3.48 kgCO2· m-2. a-1 from soil (accounting for 62.5%), 1.19 kgCO2· m-2. a-1 from litter (22.3%) and 0.67 kgCO2·m-2. a-1 from seedling (12.5%).

  7. Amplification and dampening of soil respiration by changes in temperature variability

    Science.gov (United States)

    Sierra, C.A.; Harmon, M.E.; Thomann, E.; Perakis, S.S.; Loescher, H.W.

    2011-01-01

    Accelerated release of carbon from soils is one of the most important feed backs related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature vari-ability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature.Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen there release of carbon through soil respiration as climate regimes change. The effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.

  8. Differential soil respiration responses to changing hydrologic regimes

    Science.gov (United States)

    Vincent J. Pacific; Brian L. McGlynn; Diego A. Riveros-Iregui; Howard E. Epstein; Daniel L. Welsch

    2009-01-01

    Soil respiration is tightly coupled to the hydrologic cycle (i.e., snowmelt and precipitation timing and magnitude). We examined riparian and hillslope soil respiration across a wet (2005) and a dry (2006) growing season in a subalpine catchment. When comparing the riparian zones, cumulative CO2 efflux was 33% higher, and peak efflux occurred 17 days earlier during the...

  9. [Dynamic changes in soil respiration components and their regulating factors in the Moso bamboo plantation in subtropical China].

    Science.gov (United States)

    Yang, Wen-jia; Li, Yong-fu; Jiang, Pei-kun; Zhou, Guo-mo; Liu, Juan

    2015-10-01

    Dynamic changes (from April 2013 to March 2014) in soil respiration components were investigated by Li-8100 in the Moso bamboo plantation in Lin' an City, Zhejiang Province. Results showed that the average annual values for the soil total respiration rate, heterotrophic respiration rate, and autotrophic respiration rate in the Moso bamboo plantation were 2.93, 1.92 and 1.01 imol CO2 . m-2 . s-1, respectively. The soil respiration rate and its components exhibited strongly a seasonal dynamic pattern. The maximum appeared in July 2013, and the minimum appeared in January 2014. The annual cumulative CO2 emissions through soil respiration, heterotrophic respiration, and autotrophic respiration were 37.25, 24.61 and 12.64 t CO2 . hm-2 . a-1, respectively. The soil respiration and its components showed a close relation with soil temperature of 5 cm depth, and the corresponding Q10, values at 5 cm depth were 2.05, 1.95 and 2.34, respectively. Both the soil respiration and heterotrophic respiration were correlated to soil water soluble organic C (WSOC) content, but no significant relationship between autotrophic respiration and WSOC was observed. There were no significant relationships between soil respiration components and soil moisture content or microbial biomass C. The seasonal changes in soil respiration components in the Moso bamboo plantation were predominantly controlled by the soil temperature, and the soil WSOC content was an important environmental factor controlling total soil respiration and soil heterotrophic respiration.

  10. Higher Education Support Services and Graduation Rates of Structured Education Program Students

    Science.gov (United States)

    Hepner, Seth

    2017-01-01

    The 1st-year retention rate of the Structured Education Program (SEP) is 90%, yet the 6-year graduation rate of SEP students is 29%. The gap between SEP 1st-year retention and graduation rates is the problem that this study addressed. The low graduation rate of SEP students is an important issue because graduation rates are used to measure the…

  11. Effects of Spartina alterniflora Invasion on Soil Respiration in the Yangtze River Estuary, China

    Science.gov (United States)

    Bu, Naishun; Qu, Junfeng; Li, Zhaolei; Li, Gang; Zhao, Hua; Zhao, Bin; Li, Bo; Chen, Jiakuan; Fang, Changming

    2015-01-01

    Many studies have found that plant invasion can enhance soil organic carbon (SOC) pools, by increasing net primary production (NPP) and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m−2 h−1 in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m−2 h−1 in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP), SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change. PMID:25799512

  12. Effects of Spartina alterniflora invasion on soil respiration in the Yangtze River estuary, China.

    Science.gov (United States)

    Bu, Naishun; Qu, Junfeng; Li, Zhaolei; Li, Gang; Zhao, Hua; Zhao, Bin; Li, Bo; Chen, Jiakuan; Fang, Changming

    2015-01-01

    Many studies have found that plant invasion can enhance soil organic carbon (SOC) pools, by increasing net primary production (NPP) and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m(-2) h(-1) in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m(-2) h(-1) in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP), SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change.

  13. Effects of Spartina alterniflora invasion on soil respiration in the Yangtze River estuary, China.

    Directory of Open Access Journals (Sweden)

    Naishun Bu

    Full Text Available Many studies have found that plant invasion can enhance soil organic carbon (SOC pools, by increasing net primary production (NPP and/or decreased soil respiration. While most studies have focused on C input, little attention has been paid to plant invasion effects on soil respiration, especially in wetland ecosystems. Our study examined the effects of Spartina alterniflora invasion on soil respiration and C dynamics in the Yangtze River estuary. The estuary was originally occupied by two native plant species: Phragmites australis in the high tide zone and Scirpus mariqueter in the low tide zone. Mean soil respiration rates were 185.8 and 142.3 mg CO2 m(-2 h(-1 in S. alterniflora and P. australis stands in the high tide zone, and 159.7 and 112.0 mg CO2 m(-2 h(-1 in S. alterniflora and S. mariqueter stands in the low tide zone, respectively. Aboveground NPP (ANPP, SOC, and microbial biomass were also significantly higher in the S. alterniflora stands than in the two native plant stands. S. alterniflora invasion did not significantly change soil inorganic carbon or pH. Our results indicated that enhanced ANPP by S. alterniflora exceeded invasion-induced C loss through soil respiration. This suggests that S. alterniflora invasion into the Yangtze River estuary could strengthen the net C sink of wetlands in the context of global climate change.

  14. Temperature response of respiration across heterogeneous microtopography in the Arctic tundra, Utqiaġvik, Alaska

    Science.gov (United States)

    Wilkman, E.; Zona, D.; Tang, Y.; Gioli, B.; Lipson, D.; Oechel, W. C.

    2017-12-01

    The response of ecosystem respiration to warming in the Arctic is not well constrained, partly due to the presence of ice-wedge polygons in continuous permafrost areas. These formations lead to substantial variation in vegetation, soil moisture, water table, and active layer depth over the meter scale that can drive respiratory carbon loss. Accurate calculations of in-situ temperature sensitivities (Q10) are vital for the prediction of future Arctic emissions, and while the eddy covariance technique has commonly been used to determine the diurnal and season patterns of net ecosystem exchange (NEE) of CO2, the lack of suitable dark periods in the Arctic summer has limited our ability to estimate and interpret ecosystem respiration. To therefore improve our understanding of and define controls on ecosystem respiration, we directly compared CO2 fluxes measured from automated chambers across the main local polygonised landscape forms (high and low centers, polygon rims, and polygon troughs) to estimates from an adjacent eddy covariance tower. Low-centered polygons and polygon troughs had the greatest cumulative respiration rates, and ecosystem type appeared to be the most important explanatory variable for these rates. Despite the difference in absolute respiration rates, Q10 was surprisingly similar across all microtopographic features, despite contrasting water levels and vegetation types. Conversely, Q10 varied temporally, with higher values during the early and late summer and lower values during the peak growing season. Finally, good agreement was found between chamber and tower based Q10 estimates during the peak growing season. Overall, this study suggests that it is possible to simplify estimates of the temperature sensitivity of respiration across heterogeneous landscapes, but that seasonal changes in Q10 should be incorporated into current and future model simulations.

  15. Increased Total Anesthetic Time Leads to Higher Rates of Surgical Site Infections in Spinal Fusions.

    Science.gov (United States)

    Puffer, Ross C; Murphy, Meghan; Maloney, Patrick; Kor, Daryl; Nassr, Ahmad; Freedman, Brett; Fogelson, Jeremy; Bydon, Mohamad

    2017-06-01

    A retrospective review of a consecutive series of spinal fusions comparing patient and procedural characteristics of patients who developed surgical site infections (SSIs) after spinal fusion. It is known that increased surgical time (incision to closure) is associated with a higher rate of postoperative SSIs. We sought to determine whether increased total anesthetic time (intubation to extubation) is a factor in the development of SSIs as well. In spine surgery for deformity and degenerative disease, SSI has been associated with operative time, revealing a nearly 10-fold increase in SSI rates in prolonged surgery. Surgical time is associated with infections in other surgical disciplines as well. No studies have reported whether total anesthetic time (intubation to extubation) has an association with SSIs. Surgical records were searched in a retrospective fashion to identify all spine fusion procedures performed between January 2010 and July 2012. All SSIs during that timeframe were recorded and compared with the list of cases performed between 2010 and 2012 in a case-control design. There were 20 (1.7%) SSIs in this fusion cohort. On univariate analyses of operative factors, there was a significant association between total anesthetic time (Infection 7.6 ± 0.5 hrs vs. no infection -6.0 ± 0.1 hrs, P operative time (infection 5.5 ± 0.4 hrs vs. no infection - 4.4 ± 0.06 hrs, P infections, whereas level of pathology and emergent surgery were not significant. On multivariate logistic analysis, BMI and total anesthetic time remained independent predictors of SSI whereas ASA status and operative time did not. Increasing BMI and total anesthetic time were independent predictors of SSIs in this cohort of over 1000 consecutive spinal fusions. 3.

  16. Geochemical importance of isotopic fractionation during respiration

    International Nuclear Information System (INIS)

    Schleser, G.; Foerstel, H.

    1975-01-01

    In 1935 it was found that atmospheric oxygen contained a relatively greater abundance of the 18 O isotope than did the oxygen bound in water (Dole effect). A major contribution to the fractionation of the stable oxygen isotopes should result from the respiration of microorganisms. In this respect our interest centers on the soil because nearly all organic material produced on land is decomposed within the soil. The oceans are less important because the primary productivity on land is twice the value for the oceans. In a first approach we measured the oxygen isotope fractionation during the respiration of E. coli K12 for different respiration rates. These results, accomplished with a chemostat, indicate that the fractionation factor α of the oxygen isotopes increases with the increasing respiratory activity, measured as Q/sub O 2 /. At low dilution rates or growth rates respectively of about 0.05 h -1 , the fractionation factor amounts to 1.006 increasing to 1.017 at dilution rates of about 1.0 h -1 . The results are interpreted as a kinetic mass fractionation due to the slightly different diffusion coefficients of 16 O 2 and 18 O 16 O. The respiration rates in conjunction with the corresponding fractionation data are compared with the respiration rates of typical soil microorganisms such as Azotobacter, in order to deduce fractionation data for these organisms. This is necessary to calculate a mean global fractionation factor. Understanding the Dole effect with these fractionation processes should finally give us the opportunity to calculate gas-exchange rates between the atmosphere and the oceans, on the basis of the behavior of the stable oxygen isotopes

  17. Improving respiration measurements with gas exchange analyzers.

    Science.gov (United States)

    Montero, R; Ribas-Carbó, M; Del Saz, N F; El Aou-Ouad, H; Berry, J A; Flexas, J; Bota, J

    2016-12-01

    Dark respiration measurements with open-flow gas exchange analyzers are often questioned for their low accuracy as their low values often reach the precision limit of the instrument. Respiration was measured in five species, two hypostomatous (Vitis Vinifera L. and Acanthus mollis) and three amphistomatous, one with similar amount of stomata in both sides (Eucalyptus citriodora) and two with different stomata density (Brassica oleracea and Vicia faba). CO 2 differential (ΔCO 2 ) increased two-fold with no change in apparent R d , when the two leaves with higher stomatal density faced outside. These results showed a clear effect of the position of stomata on ΔCO 2 . Therefore, it can be concluded that leaf position is important to guarantee the improvement of respiration measurements increasing ΔCO 2 without affecting the respiration results by leaf or mass units. This method will help to increase the accuracy of leaf respiration measurements using gas exchange analyzers. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Removal of boron(III) by N-methylglucamine-type cellulose derivatives with higher adsorption rate

    International Nuclear Information System (INIS)

    Inukai, Yoshinari; Tanaka, Yoshiharu; Matsuda, Toshio; Mihara, Nobutake; Yamada, Kouji; Nambu, Nobuyoshi; Itoh, Osamu; Doi, Takao; Kaida, Yasuhiko; Yasuda, Seiji

    2004-01-01

    To obtain adsorbents for boron(III) derived from a natural polymer, two forms (powder and fiber) of N-methylglucamine-type cellulose derivatives were newly synthesized. After the graft polymerization of two forms of cellulose with vinyl monomer having epoxy groups, the N-methylglucamine-type cellulose derivatives were obtained by the reaction of the grafted cellulose with N-methylglucamine. The adsorption capacities of the cellulose derivatives for boron(III) were the same levels as that of a commercially available N-methylglucamine-type polystyrene resin. However, the cellulose derivatives adsorbed boron(III) more quickly than the polystyrene resin. The adsorption and desorption of boron(III) with a column method using the cellulose fiber were achieved at a higher flow rate than that using the polystyrene resin. In addition, the boron(III), adsorbed on the cellulose fiber column, was quantitatively recovered with dilute hydrochloric acid in 20- and 200-fold increased concentrations. Consequently, it was found that the cellulose derivatives were superior to the polystyrene resin as adsorbents for boron(III) for treatment of a large quantity of wastewater

  19. Effects of long-term microgravitation exposure on cell respiration of the rat musculus soleus fibers.

    Science.gov (United States)

    Veselova, O M; Ogneva, I V; Larina, I M

    2011-07-01

    Cell respiration of the m. soleus fibers was studied in Wistar rats treated with succinic acid and exposed to microgravitation for 35 days. The results indicated that respiration rates during utilization of endogenous and exogenous substrates and the maximum respiration rate decreased in animals subjected to microgravitation without succinate treatment. The respiration rate during utilization of exogenous substrate did not increase in comparison with that on endogenous substrates. Succinic acid prevented the decrease in respiration rate on endogenous substrates and the maximum respiration rate. On the other hand, the respiration rate on exogenous substrates was reduced in vivarium control rats receiving succinate in comparison with intact control group. That could indicate changed efficiency of complex I of the respiratory chain due to reciprocal regulation of the tricarbonic acid cycle.

  20. Respirators. Does your face fit

    Energy Technology Data Exchange (ETDEWEB)

    Caro, N M; Else, D

    1981-04-01

    The authors carried out a survey of face sizes of men and women of four different ethnic origins and carried out face-seal leakage trials on four corresponding test panels. No single respirator design is likely to fit all members of the workforce, and it may be necessary to stock respirators from more than one manufacturers.Three or four different respirators or size of respirator may be needed. However, the use of lossely-fitting respirators such as Airsteam helmets could remove the necessity for exhaustive fitting procedures.

  1. Continuous fermentation and in-situ reed separation of butyric acid for higher sugar consumption rate and productivity

    DEFF Research Database (Denmark)

    Baroi, George Nabin; Skiadas, Ioannis; Westermann, Peter

    that disconnection of the REED system resulted to much lower (48 and 83% for glucose and xylose, respectively) sugars consumption rates and consequently lower butyric acid production rates. It was also noticeable that continuous operation, even without the REED system, resulted to higher glucose consumption rates...

  2. Abnormal mitochondrial respiration in failed human myocardium.

    Science.gov (United States)

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  3. Can we distinguish autotrophic respiration from heterotrophic respiration in a field site using high temporal resolution CO2 flux measurements?

    Science.gov (United States)

    Biro, Beatrice; Berger, Sina; Praetzel, Leandra; Blodau, Christian

    2016-04-01

    The processes behind C-cycling in peatlands are important to understand for assessing the vulnerability of peatlands as carbon sinks under changing climate conditions. Especially boreal peatlands are likely to underlie strong alterations in the future. It is expected that C-pools that are directly influenced by vegetation and water table fluctuations can be easily destabilized. The CO2 efflux through respiration underlies autotrophic and heterotrophic processes that show different feedbacks on changing environmental conditions. In order to understand the respiration fluxes better for more accurate modelling and prognoses, the determination of the relative importance of different respiration sources is necessary. Earlier studies used e.g. exfoliation experiments, incubation experiments or modelling approaches to estimate the different respiration sources for the total ecosystem respiration (Reco). To further the understanding in this topic, I want to distinguish autotrophic and heterotrophic respiration using high temporal resolution measurements. The study site was selected along a hydrological gradient in a peatland in southern Ontario (Canada) and measurements were conducted from May to September 2015 once per month. Environmental controls (water table, soil temperature and soil moisture) that effect the respiration sources were recorded. In my study I used a Li-COR 6400XT and a Los Gatos greenhouse gas analyzer (GGA). Reco was determined by chamber flux measurements with the GGA, while simultaneously CO2 respiration measurements on different vegetation compartments like roots, leaves and mosses were conducted using the Li-COR 6400XT. The difference between Reco and autotrophic respiration equals heterotrophic respiration. After the measurements, the vegetation plots were harvested and separated for all compartments (leaves, roots, mosses, soil organic matter), dried and weighed. The weighted respiration rates from all vegetation compartments sum up to

  4. Does adding metformin to clomifene citrate lead to higher pregnancy rates in a subset of women with polycystic ovary syndrome?

    OpenAIRE

    Moll, E.; Korevaar, J.C.; Bossuyt, P.M.M.; van der Veen, F.

    2008-01-01

    BACKGROUND An RCT among newly diagnosed, therapy naive women with polycystic ovary syndrome (PCOS) showed no significant differences in ovulation rate, ongoing pregnancy rate or spontaneous abortion rate in favour of clomifene citrate plus metformin compared with clomifene citrate. We wanted to assess whether there are specific subgroups of women with PCOS in whom clomifene citrate plus metformin leads to higher pregnancy rates. METHODS Subgroup analysis based on clinical and biochemical para...

  5. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    Science.gov (United States)

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  6. Modeling respiration from snags and coarse woody debris before and after an invasive gypsy moth disturbance

    Science.gov (United States)

    Heidi J. Renninger; Nicholas Carlo; Kenneth L. Clark; Karina V.R. Schäfer

    2014-01-01

    Although snags and coarse woody debris are a small component of ecosystem respiration, disturbances can significantly increase the mass and respiration from these carbon (C) pools. The objectives of this study were to (1) measure respiration rates of snags and coarse woody debris throughout the year in a forest previously defoliated by gypsy moths, (2) develop models...

  7. Effects of Manipulated Above- and Belowground Organic Matter Input on Soil Respiration in a Chinese Pine Plantation

    Science.gov (United States)

    Zhao, Bo; Wu, Lianhai; Zhang, Chunyu; Zhao, Xiuhai; Gadow, Klaus v.

    2015-01-01

    Alteration in the amount of soil organic matter input can have profound effect on carbon dynamics in forest soils. The objective of our research was to determine the response in soil respiration to above- and belowground organic matter manipulation in a Chinese pine (Pinus tabulaeformis) plantation. Five organic matter treatments were applied during a 2-year experiment: both litter removal and root trenching (LRRT), only litter removal (LR), control (CK), only root trenching (RT) and litter addition (LA). We found that either aboveground litter removal or root trenching decreased soil respiration. On average, soil respiration rate was significantly decreased in the LRRT treatment, by about 38.93% ± 2.01% compared to the control. Soil respiration rate in the LR treatment was 30.65% ± 1.87% and in the RT treatment 17.65% ± 1.95% lower than in the control. Litter addition significantly increased soil respiration rate by about 25.82% ± 2.44% compared to the control. Soil temperature and soil moisture were the main factors affecting seasonal variation in soil respiration. Up to the 59.7% to 82.9% seasonal variation in soil respiration is explained by integrating soil temperature and soil moisture within each of the various organic matter treatments. The temperature sensitivity parameter, Q 10, was higher in the RT (2.72) and LA (3.19) treatments relative to the control (2.51), but lower in the LRRT (1.52) and LR treatments (1.36). Our data suggest that manipulation of soil organic matter input can not only alter soil CO2 efflux, but also have profound effect on the temperature sensitivity of organic carbon decomposition in a temperate pine forest. PMID:25970791

  8. Higher USA State Resident Neuroticism Is Associated With Lower State Volunteering Rates.

    Science.gov (United States)

    McCann, Stewart J H

    2017-12-01

    Highly neurotic persons have dispositional characteristics that tend to precipitate social anxiety that discourages formal volunteering. With the 50 American states as analytical units, Study 1 found that state resident neuroticism correlated highly ( r = -.55) with state volunteering rates and accounted for another 26.8% of the volunteering rate variance with selected state demographics controlled. Study 2 replicated Study 1 during another period and extended the association to college student, senior, secular, and religious volunteering rates. Study 3 showed state resident percentages engaged in other social behaviors involving more familiarity and fewer demands than formal volunteering related to state volunteering rates but not to neuroticism. In Study 4, state resident neuroticism largely accounted statistically for relations between state volunteering rates and state population density, collectivism, social capital, Republican preference, and well-being. This research is the first to show that state resident neuroticism is a potent predictor of state volunteering rates.

  9. Predicting higher education graduation rates from institutional characteristics and resource allocation

    Directory of Open Access Journals (Sweden)

    Florence A. Hamrick

    2004-05-01

    Full Text Available This study incorporated institutional characteristics (e.g., Carnegie type, selectivity and resource allocations (e.g., instructional expenditures, student affairs expenditures into a statistical model to predict undergraduate graduation rates. Instructional expenditures, library expenditures, and a number of institutional classification variables were significant predictors of graduation rates. Based on these results, recommendations as well as warranted cautions are included about allocating academic financial resources to optimize graduation rates

  10. Do Astronauts have a Higher Rate of Orthopedic Shoulder Conditions than a Cohort of Working Professionals?

    Science.gov (United States)

    Laughlin, Mitzi S.; Murray, Jocelyn D.; Young, Millenia; Wear, Mary L.; Tarver, W. J.; Van Baalen, Mary

    2016-01-01

    Occupational surveillance of astronaut shoulder injuries began with operational concerns at the Neutral Buoyancy Laboratory (NBL) during Extra Vehicular Activity (EVA) training. NASA has implemented several occupational health initiatives during the past 20 years to decrease the number and severity of injuries, but the individual success rate is unknown. Orthopedic shoulder injury and surgery rates were calculated, but classifying the rates as normal, high or low was highly dependent on the comparison group. The purpose of this study was to identify a population of working professionals and compare orthopedic shoulder consultation and surgery rates.

  11. Respirable dust and respirable silica exposure in Ontario gold mines.

    Science.gov (United States)

    Verma, Dave K; Rajhans, Gyan S; Malik, Om P; des Tombe, Karen

    2014-01-01

    A comprehensive survey of respirable dust and respirable silica in Ontario gold mines was conducted by the Ontario Ministry of Labor during 1978-1979. The aim was to assess the feasibility of introducing gravimetric sampling to replace the assessment method which used konimeters, a device which gave results in terms of number of particles per cubic centimeter (ppcc) of air. The study involved both laboratory and field assessments. The field assessment involved measurement of airborne respirable dust and respirable silica at all eight operating gold mines of the time. This article describes the details of the field assessment. A total of 288 long-term (7-8 hr) personal respirable dust air samples were collected from seven occupational categories in eight gold mines. The respirable silica (α-quartz) was determined by x-ray diffraction method. The results show that during 1978-1979, the industry wide mean respirable dust was about 1 mg/m(3), and the mean respirable silica was 0.08 mg/m(3.)The mean% silica in respirable dust was 7.5%. The data set would be useful in future epidemiological and health studies, as well as in assessment of workers' compensation claims for occupational diseases such as silicosis, chronic obstructive pulmonary disease (COPD), and autoimmune diseases such as renal disease and rheumatoid arthritis.

  12. Soil texture drives responses of soil respiration to precipitation pulses in the sonoran desert: Implications for climate change

    Science.gov (United States)

    Cable, J.M.; Ogle, K.; Williams, D.G.; Weltzin, J.F.; Huxman, T. E.

    2008-01-01

    Climate change predictions for the desert southwestern U.S. are for shifts in precipitation patterns. The impacts of climate change may be significant, because desert soil processes are strongly controlled by precipitation inputs ('pulses') via their effect on soil water availability. This study examined the response of soil respiration-an important biological process that affects soil carbon (C) storage-to variation in pulses representative of climate change scenarios for the Sonoran Desert. Because deserts are mosaics of different plant cover types and soil textures-which create patchiness in soil respiration-we examined how these landscape characteristics interact to affect the response of soil respiration to pulses. Pulses were applied to experimental plots of bare and vegetated soil on contrasting soil textures typical of Sonoran Desert grasslands. The data were analyzed within a Bayesian framework to: (1) determine pulse size and antecedent moisture (soil moisture prior to the pulse) effects on soil respiration, (2) quantify soil texture (coarse vs. fine) and cover type (bare vs. vegetated) effects on the response of soil respiration and its components (plant vs. microbial) to pulses, and (3) explore the relationship between long-term variation in pulse regimes and seasonal soil respiration. Regarding objective (1), larger pulses resulted in higher respiration rates, particularly from vegetated fine-textured soil, and dry antecedent conditions amplified respiration responses to pulses (wet antecedent conditions dampened the pulse response). Regarding (2), autotrophic (plant) activity was a significant source (???60%) of respiration and was more sensitive to pulses on coarse- versus fine-textured soils. The sensitivity of heterotrophic (microbial) respiration to pulses was highly dependent on antecedent soil water. Regarding (3), seasonal soil respiration was predicted to increase with both growing season precipitation and mean pulse size (but only for pulses

  13. Predicting higher education graduation rates from institutional characteristics and resource allocation

    OpenAIRE

    Florence A. Hamrick; John H. Schuh; Mack C. Shelley

    2004-01-01

    This study incorporated institutional characteristics (e.g., Carnegie type, selectivity) and resource allocations (e.g., instructional expenditures, student affairs expenditures) into a statistical model to predict undergraduate graduation rates. Instructional expenditures, library expenditures, and a number of institutional classification variables were significant predictors of graduation rates. Based on these results, recommendations as well as warranted cautions are included about allocat...

  14. Results of a pilot scale melter test to attain higher production rates

    International Nuclear Information System (INIS)

    Elliott, M.L.; Perez, J.M. Jr.; Chapman, C.C.

    1991-01-01

    A pilot-scale melter test was completed as part of the effort to enhance glass production rates. The experiment was designed to evaluate the effects of bulk glass temperature and feed oxide loading. The maximum glass production rate obtained, 86 kg/hr-m 2 , was over 200% better than the previous record for the melter used

  15. Heroin addicts have higher discount rates for delayed rewards than non-drug-using controls.

    Science.gov (United States)

    Kirby, K N; Petry, N M; Bickel, W K

    1999-03-01

    Fifty-six heroin addicts and 60 age-matched controls were offered choices between monetary rewards ($11-$80) available immediately and larger rewards ($25-$85) available after delays ranging from 1 week to 6 months. Participants had a 1-in-6 chance of winning a reward that they chose on one randomly selected trial. Delay-discounting rates were estimated from the pattern of participants' choices. The discounting model of impulsiveness (Ainslie, 1975) implies that delay-discounting rates are positively correlated with impulsiveness. On average, heroin addicts' discount rates were twice those of controls (p = .004), and discount rates were positively correlated with impulsivity as measured by self-report questionnaires (p discounting rate as a measure of impulsiveness, a characteristic associated with substance abuse.

  16. Combination of On-line pH and Oxygen Transfer Rate Measurement in Shake Flasks by Fiber Optical Technique and Respiration Activity MOnitoring System (RAMOS

    Directory of Open Access Journals (Sweden)

    Jochen Büchs

    2007-12-01

    Full Text Available Shake flasks are commonly used for process development in biotechnologyindustry. For this purpose a lot of information is required from the growth conditions duringthe fermentation experiments. Therefore, Anderlei et al. developed the RAMOS technology[1, 2], which proviedes on-line oxygen and carbondioxide transfer rates in shake flasks.Besides oxygen consumption, the pH in the medium also plays an important role for thesuccessful cultivation of micro-organisms and for process development. For online pHmeasurement fiber optical methods based on fluorophores are available. Here a combinationof the on-line Oxygen Transfer Rate (OTR measurements in the RAMOS device with anon-line, fiber optical pH measurement is presented. To demonstrate the application of thecombined measurement techniques, Escherichia coli cultivations were performed and on-line pH measurements were compared with off-line samples. The combination of on-lineOTR and pH measurements gives a lot of information about the cultivation and, therefore, itis a powerful technique for monitoring shake flask experiments as well as for processdevelopment.

  17. Adhesion of the clay minerals montmorillonite, kaolinite, and attapulgite reduces respiration of Histoplasma capsulatum.

    Science.gov (United States)

    Lavie, S; Stotzky, G

    1986-01-01

    The respiration of three phenotypes of Histoplasma capsulatum, the causal agent of histoplasmosis in humans, was markedly reduced by low concentrations of montmorillonite but was reduced less by even higher concentrations of kaolinite or attapulgite (palygorskite). The reduction in respiration followed a pattern that suggested saturation-type kinetics: an initial sharp reduction that occurred with low concentrations of clay (0.01 to 0.5% [wt/vol]), followed by a more gradual reduction with higher concentrations (1 to 8%). Increases in viscosity (which could impair the movement of O2) caused by the clays were not responsible for the reduction in respiration, and the clays did not interfere with the availability of nutrients. Scanning electron microscopy after extensive washing showed that the clay particles were tightly bound to the hyphae, suggesting that the clays reduced the rate of respiration of H. capsulatum by adhering to the mycelial surface and, thereby, interfered with the movement of nutrients, metabolites, and gases across the mycelial wall.

  18. [Temporal-spatial distribution of agricultural diffuse nitrogen pollution and relationship with soil respiration and nitrification].

    Science.gov (United States)

    Wei, Ouyang; Cai, Guan-Qing; Huang, Hao-Bo; Geng, Xiao-Jun

    2014-06-01

    The soil respiration, nitrification and denitrification processes play an important role on soil nitrogen transformation and diffuse nitrogen loading. These processes are also the chains for soil circle. In this study, the Zhegao watershed located north of Chaohu Lake was selected to explore the interactions of these processes with diffuse nitrogen pollution. The BaPS (Barometric Process Separation) was applied to analyze the soil respiration, nitrification and denitrification processes in farmland and forest. The SWAT (Soil and Water Assessment Tool) simulated the temporal and spatial pattern of diffuse nitrogen loading. As the expanding of farmland and higher level of fertilization, the yearly mean loading of diffuse nitrogen increased sustainably from 1980-1995 to 1996-2012. The monthly loading in 1996-2012 was also higher than that in the period of 1980-1995, which closely related to the precipitation. The statistical analysis indicated that there was a significant difference between two periods. The yearly averaged loading of the whole watershed in 1996-2012 was 10.40 kg x hm(-2), which was 8.10 kg x hm(-2) in 1980-1995. The variance analysis demonstrated that there was also a big difference between the spatial distributions of two periods. The forest soil had much higher soil respiration than the farmland soil. But the farmland had higher nitrification and denitrification rates. The more intensive nitrogen transformation in the farmland contributed to the less diffuse nitrogen loading. As the nitrification rate of farmland was higher than denitrification rate, agricultural diffuse nitrate nitrogen loading would increase and organic nitrogen loading would reduce. The analysis of soil respiration, nitrification and denitrification is helpful for the study of soil nitrogen circle form the aspect of soil biology, which also benefits the control of agricultural diffuse nitrogen pollution.

  19. Mussel farming impact on pelagic production and respiration rates in a coastal upwelling embayment (Ría de Vigo, NW Spain)

    Science.gov (United States)

    Froján, María; Castro, Carmen G.; Zúñiga, Diana; Arbones, Belén; Alonso-Pérez, Fernando; Figueiras, Francisco G.

    2018-05-01

    This paper provides the first diagnosis of the impact of mussel farming on the primary production (PP) and the metabolic balance in a coastal upwelling region (Ría de Vigo). Measurements of size-fractionated PP and microbial plankton metabolism were performed outside (reference station; ReS) and inside the farming area (raft station; RaS). At ReS, integrated PP was higher during upwelling (1.05 ± 0.45 g C m-2 d-1) with microphytoplankton dominating carbon fixation (74 ± 14%). The significance of nanophytoplankton and picophytoplankton increased during winter linked to lower PP (0.24 ± 0.03 g C m-2 d-1). Water column at ReS was always autotrophic with net community production (NCP) ranging from 186 ± 67 mmol O2 m-2 d-1 during upwelling to 43 ± 22 mmol O2 m-2 d-1 in winter. At RaS, there was a decrease in PP attributable not only to mussel consumption but also to the lower irradiance under mussel rafts. Concomitant decrease in NCP was also observed (by 56%), yet remained autotrophic, supporting the view that under current conditions food does not limit mussel growth in the Ría, thus securing the carrying capacity of the system in terms of production.

  20. Are Interpersonal Violence Rates Higher Among Young Women in College Compared With Those Never Attending College?

    Science.gov (United States)

    Coker, Ann L; Follingstad, Diane R; Bush, Heather M; Fisher, Bonnie S

    2016-05-01

    Estimates of sexual violence and partner violence rates among young women are generated primarily from college samples. Few studies have data to compare rates among similar-aged women attending college with those who never attended college. This study aims to estimate rates of partner violence by type (sexual, physical, and psychological) and severity (mild, moderate, severe), sexual harassment, and knowing or suspecting that someone put a drug in a drink (drugged drink) among a national sample of 959 young women aged 18 to 24 in an intimate relationship in the past 12 months who were either currently in college (college;n= 272) or never attended college (non-college;n= 687). After adjusting for demographic differences between these two groups, no significant differences were found in rates of sexual partner violence (28.4% non-college, 23.5% college), physical partner violence (27.9% non-college, 26.3% college), psychological partner violence (Mscore: 6.10 non-college, 5.59 college), sexual harassment (15.5% non-college, 14.1% college), or drugged drink (8.5% non-college, 7.8% college). Finding high rates of interpersonal violence among young women who are and are not currently attending college indicates the need to target all young adults with violence prevention interventions in educational, workplace, and other community-based settings. © The Author(s) 2015.

  1. Higher speciation and lower extinction rates influence mammal diversity gradients in Asia.

    Science.gov (United States)

    Tamma, Krishnapriya; Ramakrishnan, Uma

    2015-02-04

    Little is known about the patterns and correlates of mammal diversity gradients in Asia. In this study, we examine patterns of species distributions and phylogenetic diversity in Asia and investigate if the observed diversity patterns are associated with differences in diversification rates between the tropical and non-tropical regions. We used species distribution maps and phylogenetic trees to generate species and phylogenetic diversity measures for 1° × 1° cells across mainland Asia. We constructed lineage-through-time plots and estimated diversification shift-times to examine the temporal patterns of diversifications across orders. Finally, we tested if the observed gradients in Asia could be associated with geographical differences in diversification rates across the tropical and non-tropical biomes. We estimated speciation, extinction and dispersal rates across these two regions for mammals, both globally and for Asian mammals. Our results demonstrate strong latitudinal and longitudinal gradients of species and phylogenetic diversity with Southeast Asia and the Himalayas showing highest diversity. Importantly, our results demonstrate that differences in diversification (speciation, extinction and dispersal) rates between the tropical and the non-tropical biomes influence the observed diversity gradients globally and in Asia. For the first time, we demonstrate that Asian tropics act as both cradles and museums of mammalian diversity. Temporal and spatial variation in diversification rates across different lineages of mammals is an important correlate of species diversity gradients observed in Asia.

  2. Vigorous physical activity predicts higher heart rate variability among younger adults.

    Science.gov (United States)

    May, Richard; McBerty, Victoria; Zaky, Adam; Gianotti, Melino

    2017-06-14

    Baseline heart rate variability (HRV) is linked to prospective cardiovascular health. We tested intensity and duration of weekly physical activity as predictors of heart rate variability in young adults. Time and frequency domain indices of HRV were calculated based on 5-min resting electrocardiograms collected from 82 undergraduate students. Hours per week of both moderate and vigorous activity were estimated using the International Physical Activity Questionnaire. In regression analyses, hours of vigorous physical activity, but not moderate activity, significantly predicted greater time domain and frequency domain indices of heart rate variability. Adjusted for weekly frequency, greater daily duration of vigorous activity failed to predict HRV indices. Future studies should test direct measurements of vigorous activity patterns as predictors of autonomic function in young adulthood.

  3. Reducing Error Rates for Iris Image using higher Contrast in Normalization process

    Science.gov (United States)

    Aminu Ghali, Abdulrahman; Jamel, Sapiee; Abubakar Pindar, Zahraddeen; Hasssan Disina, Abdulkadir; Mat Daris, Mustafa

    2017-08-01

    Iris recognition system is the most secured, and faster means of identification and authentication. However, iris recognition system suffers a setback from blurring, low contrast and illumination due to low quality image which compromises the accuracy of the system. The acceptance or rejection rates of verified user depend solely on the quality of the image. In many cases, iris recognition system with low image contrast could falsely accept or reject user. Therefore this paper adopts Histogram Equalization Technique to address the problem of False Rejection Rate (FRR) and False Acceptance Rate (FAR) by enhancing the contrast of the iris image. A histogram equalization technique enhances the image quality and neutralizes the low contrast of the image at normalization stage. The experimental result shows that Histogram Equalization Technique has reduced FRR and FAR compared to the existing techniques.

  4. Higher contamination rate than usual. Treatment and disinfection of water in hot whirlpool systems

    Energy Technology Data Exchange (ETDEWEB)

    Herschman, W

    1985-10-01

    Hot whirlpools must meet the hygienic standards set in the Federal Law Concerning Prevention of Epidemics of 18 Dec 1979. The low water volume of whirlpool systems and the extraordinary contamination rate in uninterrupted operation require a specific water treatment and disinfestation technology to make up for the poor buffer capacity of the low water volume. (orig./BWI).

  5. Mechanisms promoting higher growth rate in arctic than in temperate shorebirds

    NARCIS (Netherlands)

    Schekkerman, H.; Tulp, I.Y.M.; Piersma, T.; Visser, G.H.

    2003-01-01

    We compared prefledging growth, energy expenditure, and time budgets in the arctic-breeding red knot (Calidris canutus) to those in temperate shorebirds, to investigate how arctic chicks achieve a high growth rate despite energetic difficulties associated with precocial development in a cold

  6. Mechanisms promoting higher growth rate in arctic than in temperate shorebirds

    NARCIS (Netherlands)

    Schekkerman, H; Tulp, Ingrid; Piersma, T.; Visser, G.H.

    We compared prefledging growth, energy expenditure, and time budgets in the arctic-breeding red knot (Calidris canutus) to those in temperate shorebirds, to investigate how arctic chicks achieve a high growth rate despite energetic difficulties associated with precocial development in a cold

  7. Honest signaling in trust interactions: smiles rated as genuine induce trust and signal higher earning opportunities

    OpenAIRE

    Centorrino, S.; Djemai, E.; Hopfensitz, A.; Milinski, M.; Seabright, P.

    2015-01-01

    We test the hypothesis that smiles perceived as honest serve as a signal that has evolved to induce cooperation in situations requiring mutual trust. Potential trustees (84 participants from Toulouse, France) made two video clips averaging around 15 seconds for viewing by potential senders before the latter decided whether to ‘send’ or ‘keep’ a lower stake (4 euros) or higher stake (8 euros). Senders (198 participants from Lyon, France) made trust decisions with respect to the recorded clips....

  8. Surgical site infection and transfusion rates are higher in underweight total knee arthroplasty patients

    Directory of Open Access Journals (Sweden)

    Jorge Manrique, MD

    2017-03-01

    Conclusions: Our study demonstrates that UW TKA patients have a higher likelihood of developing SSI and requiring blood transfusions. The specific reasons are unclear, but we conjecture that it may be related to decreased wound healing capabilities and low preoperative hemoglobin. Investigation of local tissue coverage and hematologic status may be beneficial in this patient population to prevent SSI. Based on the results of this study, a prospective evaluation of these factors should be undertaken.

  9. Accuracy of rate coding: When shorter time window and higher spontaneous activity help

    Czech Academy of Sciences Publication Activity Database

    Leváková, Marie; Tamborrino, M.; Košťál, Lubomír; Lánský, Petr

    2017-01-01

    Roč. 95, č. 2 (2017), č. článku 022310. ISSN 2470-0045 R&D Projects: GA ČR(CZ) GA15-08066S; GA MŠk(CZ) 7AMB17AT048 Institutional support: RVO:67985823 Keywords : rate coding * observation window * spontaneous activity * Fisher information * perfect integrate- and -fire model * Wiener process Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology Impact factor: 2.366, year: 2016

  10. A MEMS turbine prototype for respiration harvesting

    Science.gov (United States)

    Goreke, U.; Habibiabad, S.; Azgin, K.; Beyaz, M. I.

    2015-12-01

    The design, manufacturing, and performance characterization of a MEMS-scale turbine prototype is reported. The turbine is designed for integration into a respiration harvester that can convert normal human breathing into electrical power through electromagnetic induction. The device measures 10 mm in radius, and employs 12 blades located around the turbine periphery along with ball bearings around the center. Finite element simulations showed that an average torque of 3.07 μNm is induced at 12 lpm airflow rate, which lies in normal breathing levels. The turbine and a test package were manufactured using CNC milling on PMMA. Tests were performed at respiration flow rates between 5-25 lpm. The highest rotational speed was measured to be 9.84 krpm at 25 lpm, resulting in 8.96 mbar pressure drop across the device and 370 mW actuation power.

  11. Herd protection effect of N95 respirators in healthcare workers.

    Science.gov (United States)

    Chen, Xin; Chughtai, Abrar Ahmad; MacIntyre, Chandini Raina

    2017-12-01

    Objective To determine if there was herd protection conferred to unprotected healthcare workers (HCWs) by N95 respirators worn by colleagues. Methods Data were analysed from a prospective cluster randomized clinical trial conducted in Beijing, China between 1 December 2008 and 15 January 2009. A minimum compliance level (MCL) of N95 respirators for prevention of clinical respiratory illness (CRI) was set based on various compliance cut-offs. The CRI rates were compared between compliant (≥MCL) and non-compliant (protection from use of N95 respirators by colleagues within a hospital ward.

  12. Comparison of higher order spectra in heart rate signals during two techniques of meditation: Chi and Kundalini meditation.

    Science.gov (United States)

    Goshvarpour, Ateke; Goshvarpour, Atefeh

    2013-02-01

    The human heartbeat is one of the important examples of complex physiologic fluctuations. For the first time in this study higher order spectra of heart rate signals during meditation have explored. Specifically, the aim of this study was to analysis and compares the contribution of quadratic phase coupling of human heart rate variability during two forms of meditation: (1) Chinese Chi (or Qigong) meditation and (2) Kundalini Yoga meditation. For this purpose, Bispectrum was estimated by using biased, parametric and the direct (FFT) method. The results show that the mean Bispectrum magnitude of heart rate signals increased during Kundalini Yoga meditation, but it decreased significantly during Chi meditation. However, in both meditation techniques phase-coupled harmonics are shifted to the higher frequencies during meditation. In addition, it has shown that not only there are significant differences between rest and meditation states, but also heart rate patterns appear to be influenced by different types of meditation.

  13. Seasonal changes in temperature and nutrient control of photosynthesis, respiration and growth of natural phytoplankton communities

    DEFF Research Database (Denmark)

    Stæhr, P. A.; Sand-Jensen, K.

    2006-01-01

    cultures in seasons of low ambient nutrient availability. 3. Temperature stimulation of growth and metabolism was higher at low than high ambient temperature showing that long-term temperature acclimation of the phytoplankton community before the experiments was of great importance for the measured rates...... +2, +4 and +6 °C for 2 weeks with and without addition of extra inorganic nutrients. 2. Rates of photosynthesis, respiration and growth generally increased with temperature, but this effect was strongly enhanced by high nutrient availability, and therefore was most evident for nutrient amended......1. To investigate the influence of elevated temperatures and nutrients on photosynthesis, respiration and growth of natural phytoplankton assemblages, water was collected from a eutrophic lake in spring, summer, autumn, winter and the following spring and exposed to ambient temperature and ambient...

  14. The Role of Microbial Community Composition in Controlling Soil Respiration Responses to Temperature.

    Science.gov (United States)

    Auffret, Marc D; Karhu, Kristiina; Khachane, Amit; Dungait, Jennifer A J; Fraser, Fiona; Hopkins, David W; Wookey, Philip A; Singh, Brajesh K; Freitag, Thomas E; Hartley, Iain P; Prosser, James I

    2016-01-01

    Rising global temperatures may increase the rates of soil organic matter decomposition by heterotrophic microorganisms, potentially accelerating climate change further by releasing additional carbon dioxide (CO2) to the atmosphere. However, the possibility that microbial community responses to prolonged warming may modify the temperature sensitivity of soil respiration creates large uncertainty in the strength of this positive feedback. Both compensatory responses (decreasing temperature sensitivity of soil respiration in the long-term) and enhancing responses (increasing temperature sensitivity) have been reported, but the mechanisms underlying these responses are poorly understood. In this study, microbial biomass, community structure and the activities of dehydrogenase and β-glucosidase enzymes were determined for 18 soils that had previously demonstrated either no response or varying magnitude of enhancing or compensatory responses of temperature sensitivity of heterotrophic microbial respiration to prolonged cooling. The soil cooling approach, in contrast to warming experiments, discriminates between microbial community responses and the consequences of substrate depletion, by minimising changes in substrate availability. The initial microbial community composition, determined by molecular analysis of soils showing contrasting respiration responses to cooling, provided evidence that the magnitude of enhancing responses was partly related to microbial community composition. There was also evidence that higher relative abundance of saprophytic Basidiomycota may explain the compensatory response observed in one soil, but neither microbial biomass nor enzymatic capacity were significantly affected by cooling. Our findings emphasise the key importance of soil microbial community responses for feedbacks to global change, but also highlight important areas where our understanding remains limited.

  15. Religious affiliation and psychiatric morbidity in Brazil: higher rates among evangelicals and spiritists.

    Science.gov (United States)

    Dalgalarrondo, Paulo; Marín-León, Leticia; Botega, Neury José; Berti De Azevedo Barros, Marilisa; Bosco De Oliveira, Helenice

    2008-11-01

    To verify the association between the prevalence of mental symptoms and excessive alcohol intake with religious affiliation, church attendance and personal religiosity. A household survey of 515 adults randomly sampled included the WHO SUPRE-MISS questionnaire, SRQ-20 and AUDIT. Weighted prevalences were estimated and logistic analyses were performed. Minor psychiatric morbidity was greater among Spiritists and Protestants/ Evangelicals than in Catholics and in the ;no-religion' group. The latter had a greater frequency of abusive alcohol drinking pattern and Protestants/Evangelicals showed lower drinking patterns. Although belonging to Protestant/Evangelical churches in Brazil may inhibit alcohol involvement it seems to be associated to a higher frequency of depressive symptoms. Processes of seeking relief in new religious affiliations among sub-groups with previous minor psychiatric symptoms may probably occur in the Brazilian society.

  16. Higher rate of compensation after surgical treatment versus conservative treatment for acute Achilles tendon rupture

    DEFF Research Database (Denmark)

    Sveen, Thor-Magnus; Troelsen, Anders; Barfod, Kristoffer Weisskirchner

    2015-01-01

    in the period from 1992 to 2010 in the DPIA database were identified and patient records were reviewed manually. RESULTS: The compensation awarded for the 18-year period totalled 18,147,202 DKK with 41% of patient claims being recognised. Out of 180 surgically treated patients, 79 received a total compensation...... of 14,051,377 DKK, median 47,637 (range: 5,000-3,577,043). Of 114 non-surgically treated patients, 40 received 3,715,224 DKK in compensation, with a median amount of 35,788 DKK (range: 5,000-830,073). CONCLUSION: Compensation after surgical treatment was 3.8 times higher than compensation after non......-surgical treatment. It is noteworthy that 34.5% of patients had an overlooked diagnosis which underlines the importance of a correct primary diagnosis. FUNDING: not relevant. TRIAL REGISTRATION: not relevant....

  17. Weaker gun state laws are associated with higher rates of suicide secondary to firearms.

    Science.gov (United States)

    Alban, Rodrigo F; Nuño, Miriam; Ko, Ara; Barmparas, Galinos; Lewis, Azaria V; Margulies, Daniel R

    2018-01-01

    Firearm-related suicides comprise over two-thirds of gun-related violence in the United States, and gun laws and policies remain under scrutiny, with many advocating for revision of the regulatory map for lawful gun ownership, aiming at restricting access and distribution of these weapons. However, the quantitative relationship between how strict gun laws are and the incidence of firearm violence with their associated mortality is largely unknown. We therefore, sought to explore the impact of firearm law patterns among states on the incidence and outcomes of firearm-related suicide attempts, utilizing established objective criteria. The National Inpatient Sample for the years 1998-2011 was queried for all firearm-related suicides. Discharge facilities were stratified into five categories (A, B, C, D, and F, with A representing states with the most strict and F representing states with the least strict laws) based on the Brady Campaign to prevent Gun Violence that assigns scorecards for every state. The primary outcomes were suicide attempts and in-hospital mortality per 100,000 populations by Brady state grade. During the 14-year study period, 34,994 subjects met inclusion criteria. The mean age was 42.0 years and 80.1% were male. A handgun was utilized by 51.8% of patients. The overall mortality was 33.3%. Overall, 22.0% had reported psychoses and 19.3% reported depression. After adjusting for confounding factors and using group A as reference, there were higher adjusted odds for suicide attempts for patients admitted in group C, D, and F category states (1.73, 2.09, and 1.65, respectively, all P gun laws, and these injuries tend to be associated with a higher mortality. Efforts aimed at nationwide standardization of firearm state laws are warranted, particularly for young adults and suicide-prone populations. III. Trauma Outcomes study. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Distinct responses of soil respiration to experimental litter manipulation in temperate woodland and tropical forest.

    Science.gov (United States)

    Bréchet, Laëtitia M; Lopez-Sangil, Luis; George, Charles; Birkett, Ali J; Baxendale, Catherine; Castro Trujillo, Biancolini; Sayer, Emma J

    2018-04-01

    Global change is affecting primary productivity in forests worldwide, and this, in turn, will alter long-term carbon (C) sequestration in wooded ecosystems. On one hand, increased primary productivity, for example, in response to elevated atmospheric carbon dioxide (CO 2 ), can result in greater inputs of organic matter to the soil, which could increase C sequestration belowground. On other hand, many of the interactions between plants and microorganisms that determine soil C dynamics are poorly characterized, and additional inputs of plant material, such as leaf litter, can result in the mineralization of soil organic matter, and the release of soil C as CO 2 during so-called "priming effects". Until now, very few studies made direct comparison of changes in soil C dynamics in response to altered plant inputs in different wooded ecosystems. We addressed this with a cross-continental study with litter removal and addition treatments in a temperate woodland (Wytham Woods) and lowland tropical forest (Gigante forest) to compare the consequences of increased litterfall on soil respiration in two distinct wooded ecosystems. Mean soil respiration was almost twice as high at Gigante (5.0 μmol CO 2  m -2  s -1 ) than at Wytham (2.7 μmol CO 2  m -2  s -1 ) but surprisingly, litter manipulation treatments had a greater and more immediate effect on soil respiration at Wytham. We measured a 30% increase in soil respiration in response to litter addition treatments at Wytham, compared to a 10% increase at Gigante. Importantly, despite higher soil respiration rates at Gigante, priming effects were stronger and more consistent at Wytham. Our results suggest that in situ priming effects in wooded ecosystems track seasonality in litterfall and soil respiration but the amount of soil C released by priming is not proportional to rates of soil respiration. Instead, priming effects may be promoted by larger inputs of organic matter combined with slower turnover rates.

  19. Lead Burden as a Factor for Higher Complication Rate in Patients With Implantable Cardiac Devices

    Directory of Open Access Journals (Sweden)

    Christopher Kolibash

    2015-01-01

    Full Text Available Purpose: Lead revisions have increased over the last decade. Patients who do not undergo lead extraction face an increased lead burden. Consequences of increased lead burden have not been fully defined. We sought to characterize the complication rate and outcomes in patients with sterile redundant leads. Methods: We retrospectively reviewed 242 consecutive patients [mean age 74 ± 12 years; 66.9% male] who underwent lead revision that resulted in an abandoned lead from January 2005 to June 2010. Patients were placed in a cohort based on number of leads after last recorded procedure (Group A: ≤2 [n=58]; Group B: 3-4 [n=168]; Group C: ≥5 [n=16]. Prespecified inhospital and long-term follow-up events were compared. Mortality rates were obtained from Social Security Death Index. Median follow-up was 2 years. Results: Baseline age, gender and race demographics were similar among the three groups. Increasing lead burden was associated with more adverse periprocedural events (A: 3.4%, B: 10.1%, C: 25.0%; P=0.031 and long-term device-related events (A: 1.7%, B: 13.0%, C: 18.8%; P=0.031. Device-related readmissions increased in frequency as lead burden increased (A: 3.5%, B: 18.5%, C: 37.5%; P=0.002. Combined periprocedural and late events also increased with more redundant leads (A: 5.2%, B: 23.2%, C: 44.0%; P=0.001. Total major events were infrequent (3.3%. There was no procedure-related mortality. Long-term all-cause mortality was not significantly different (A: 17.2%, B: 23.8%, C: 25.0%; P=0.567. Conclusions: Greater lead burden was associated with increased number of periprocedural and long-term minor events. It did not significantly impact major events or mortality.

  20. Global spatiotemporal distribution of soil respiration modeled using a global database

    Science.gov (United States)

    Hashimoto, S.; Carvalhais, N.; Ito, A.; Migliavacca, M.; Nishina, K.; Reichstein, M.

    2015-07-01

    The flux of carbon dioxide from the soil to the atmosphere (soil respiration) is one of the major fluxes in the global carbon cycle. At present, the accumulated field observation data cover a wide range of geographical locations and climate conditions. However, there are still large uncertainties in the magnitude and spatiotemporal variation of global soil respiration. Using a global soil respiration data set, we developed a climate-driven model of soil respiration by modifying and updating Raich's model, and the global spatiotemporal distribution of soil respiration was examined using this model. The model was applied at a spatial resolution of 0.5°and a monthly time step. Soil respiration was divided into the heterotrophic and autotrophic components of respiration using an empirical model. The estimated mean annual global soil respiration was 91 Pg C yr-1 (between 1965 and 2012; Monte Carlo 95 % confidence interval: 87-95 Pg C yr-1) and increased at the rate of 0.09 Pg C yr-2. The contribution of soil respiration from boreal regions to the total increase in global soil respiration was on the same order of magnitude as that of tropical and temperate regions, despite a lower absolute magnitude of soil respiration in boreal regions. The estimated annual global heterotrophic respiration and global autotrophic respiration were 51 and 40 Pg C yr-1, respectively. The global soil respiration responded to the increase in air temperature at the rate of 3.3 Pg C yr-1 °C-1, and Q10 = 1.4. Our study scaled up observed soil respiration values from field measurements to estimate global soil respiration and provide a data-oriented estimate of global soil respiration. The estimates are based on a semi-empirical model parameterized with over one thousand data points. Our analysis indicates that the climate controls on soil respiration may translate into an increasing trend in global soil respiration and our analysis emphasizes the relevance of the soil carbon flux from soil to

  1. Respiration of the external mycelium in the arbuscular mycorrhizal symbiosis shows strong dependence on recent photosynthates and acclimation to temperature.

    Science.gov (United States)

    Heinemeyer, A; Ineson, P; Ostle, N; Fitter, A H

    2006-01-01

    * Although arbuscular mycorrhizal (AM) fungi are a major pathway in the global carbon cycle, their basic biology and, in particular, their respiratory response to temperature remain obscure. * A pulse label of the stable isotope (13)C was applied to Plantago lanceolata, either uninoculated or inoculated with the AM fungus Glomus mosseae. The extra-radical mycelium (ERM) of the fungus was allowed to grow into a separate hyphal compartment excluding roots. We determined the carbon costs of the ERM and tested for a direct temperature effect on its respiration by measuring total carbon and the (13)C:(12)C ratio of respired CO(2). With a second pulse we tested for acclimation of ERM respiration after 2 wk of soil warming. * Root colonization remained unchanged between the two pulses but warming the hyphal compartment increased ERM length. delta(13)C signals peaked within the first 10 h and were higher in mycorrhizal treatments. The concentration of CO(2) in the gas samples fluctuated diurnally and was highest in the mycorrhizal treatments but was unaffected by temperature. Heating increased ERM respiration only after the first pulse and reduced specific ERM respiration rates after the second pulse; however, both pulses strongly depended on radiation flux. * The results indicate a fast ERM acclimation to temperature, and that light is the key factor controlling carbon allocation to the fungus.

  2. An integrated approach for a higher success rate in mergers and acquisitions

    Directory of Open Access Journals (Sweden)

    Andrej Bertoncelj

    2007-05-01

    Full Text Available The paper outlines the importance of balanced management of hard and soft key success factors, combining the economic logic of corporate performance and human capital through an integrated approach to mergers and acquisitions. The study, based on a questionnaire and interviews, suggests that the achievement level ofmergers and acquisitions’ objectives of acquiring companies in Slovenia should be comparable to findings of similar studies; namely, the objectives that drove the deal were met only half the time. The results indicate that five hard success factors – a professional target search and due diligence, a realistic assessment of synergies, theright mix of financial sources, a detailed post-acquisition integration plan already prepared in the pre-deal phase and its speedy implementation – and five soft success factors – a new “combined” organizational culture, a competent management team, innovative employees, efficient and consistent communication and a creative business environment – are becoming increasingly relevant. Even though they differ in their importance for individual companies in the sample, they are all considered essential to increasing the success rate of corporate combinations

  3. Sex-role reversal of a monogamous pipefish without higher potential reproductive rate in females.

    Science.gov (United States)

    Sogabe, Atsushi; Yanagisawa, Yasunobu

    2007-12-07

    In monogamous animals, males are usually the predominant competitors for mates. However, a strictly monogamous pipefish Corythoichthys haematopterus exceptionally exhibits a reversed sex role. To understand why its sex role is reversed, we measured the adult sex ratio and the potential reproductive rate (PRR), two principal factors influencing the operational sex ratio (OSR), in a natural population of southern Japan. The adult sex ratio was biased towards females throughout the breeding season, but the PRR, which increased with water temperature, did not show sexual difference. We found that an alternative index of the OSR (Sf/Sm: sex ratio of 'time in') calculated from the monthly data was consistently biased towards females. The female-biased OSR associated with sex-role reversal has been reported in some polyandrous or promiscuous pipefish, but factors biasing the OSR differed between these pipefish and C. haematopterus. We concluded that the similar PRR between the sexes in C. haematopterus does not confer reproductive benefit of polygamous mating on either sex, resulting in strict monogamous mating, and its female-biased adult sex ratio promotes female-female competition for a mate, resulting in sex-role reversal.

  4. Lower serotonin level and higher rate of fibromyalgia syndrome with advancing pregnancy.

    Science.gov (United States)

    Atasever, Melahat; Namlı Kalem, Muberra; Sönmez, Çiğdem; Seval, Mehmet Murat; Yüce, Tuncay; Sahin Aker, Seda; Koç, Acar; Genc, Hakan

    2017-09-01

    The aim of the study is to investigate the relationship between changes in serotonin levels during pregnancy and fibromyalgia syndrome (FS) and the relationships between FS and the physical/psychological state, biochemical and hormonal parameters, which may be related to the musculoskeletal system. This study is a prospective case-control study conducted with 277 pregnant women at the obstetric unit of Ankara University Faculty of Medicine, in the period between January and June 2015. FS was determined based on the presence or absence of the 2010 ACR diagnostic criteria and all the volunteers were asked to answer the questionnaires as Fibromyalgia Impact Criteria (FIQ), Widespread Pain Index (WPI), Symptom Severity Scale (SS), Beck Depression Inventory and Visual Analog Scale (VAS). Biochemical and hormonal markers (glucose, TSH, T4, Ca (calcium), P (phosphate), PTH (parathyroid hormone) and serotonin levels) relating to muscle and bone metabolism were measured. In the presence of fibromyalgia, the physical and psychological parameters are negatively affected (p serotonin levels may contribute to the development of fibromyalgia but this was not statistically significant. The Beck Depression Inventory scale statistically showed that increasing scores also increase the risk of fibromyalgia (p serotonin levels in women with FS are lower than the control group and that serotonin levels reduce as pregnancy progresses. Anxiety and depression in pregnant women with FS are higher than the control group. The presence of depression increases the likelihood of developing FS at a statistically significant level. Serotonin impairment also increases the chance of developing FS, but this correlation has not been shown to be statistically significant.

  5. Biodegradation testing of chemicals with high Henry’s constants – separating mass and effective concentration reveals higher rate constants

    DEFF Research Database (Denmark)

    Birch, Heidi; Andersen, Henrik Rasmus; Comber, Mike

    Microextraction (HS-SPME) was applied directly on the test systems to measure substrate depletion by biodegradation relative to abiotic controls. HS-SPME was also applied to determine air to water partitioning ratios. Water phase biodegradation rate constants, kwater, were up to 72 times higher than test system...

  6. Higher dosage nicotine patches increase one-year smoking cessation rates : results from the European CEASE trial

    NARCIS (Netherlands)

    Tonnesen, P; Paoletti, P; Gustavsson, G; Russell, MA; Saracci, R; Gulsvik, A; Rijcken, B

    The Collaborative European Anti-Smoking Evaluation (CEASE) was a European multicentre, randomized, double-blind placebo controlled smoking cessation study, The objectives were to determine whether higher dosage and longer duration of nicotine patch therapy would increase the success rate. Thirty-six

  7. Understanding the Effect of Response Rate and Class Size Interaction on Students Evaluation of Teaching in a Higher Education

    Science.gov (United States)

    Al Kuwaiti, Ahmed; AlQuraan, Mahmoud; Subbarayalu, Arun Vijay

    2016-01-01

    Objective: This study aims to investigate the interaction between response rate and class size and its effects on students' evaluation of instructors and the courses offered at a higher education Institution in Saudi Arabia. Study Design: A retrospective study design was chosen. Methods: One thousand four hundred and forty four different courses…

  8. Children Receiving Free or Reduced-Price School Lunch Have Higher Food Insufficiency Rates in Summer.

    Science.gov (United States)

    Huang, Jin; Barnidge, Ellen; Kim, Youngmi

    2015-09-01

    In 2012, 20% of households in the United States with children lacked consistent access to adequate food. Food insufficiency has significant implications for children, including poor physical and mental health outcomes, behavior problems, and low educational achievements. The National School Lunch Program (NSLP) is one policy solution to reduce food insufficiency among children from low-income families. The objective of this project was to evaluate the association between NSLP participation and household food insufficiency by examining trajectories of food insufficiency over 10 calendar months. The calendar months included both nonsummer months when school is in session and summer months when school is out of session. The study used the data from the Survey of Income and Program Participation and conducted linear growth curve analyses in the multilevel modeling context. Comparisons were made between the trajectories of food insufficiencies among recipients of free or reduced-price lunch and their counterparts who are eligible but choose not to participate in the program. Heads of households that included children receiving free or reduced-price lunch (n = 6867) were more likely to be female, black, unmarried, and unemployed, and have a lower educational attainment than those whose children were eligible but did not receive free or reduced-price lunch (n = 11,396). For households participating in the NSLP, the food insufficiency rate was consistent from January to May at ∼4%, and then increased in June and July to >5%. Meanwhile, food insufficiency among eligible nonrecipients was constant throughout the year at nearly 2%. The NSLP protects households from food insufficiency. Policies should be instituted to make enrollment easier for households. © 2015 American Society for Nutrition.

  9. Informatics technology mimics ecology: dense, mutualistic collaboration networks are associated with higher publication rates.

    Directory of Open Access Journals (Sweden)

    Marco D Sorani

    Full Text Available Information technology (IT adoption enables biomedical research. Publications are an accepted measure of research output, and network models can describe the collaborative nature of publication. In particular, ecological networks can serve as analogies for publication and technology adoption. We constructed network models of adoption of bioinformatics programming languages and health IT (HIT from the literature.We selected seven programming languages and four types of HIT. We performed PubMed searches to identify publications since 2001. We calculated summary statistics and analyzed spatiotemporal relationships. Then, we assessed ecological models of specialization, cooperativity, competition, evolution, biodiversity, and stability associated with publications.Adoption of HIT has been variable, while scripting languages have experienced rapid adoption. Hospital systems had the largest HIT research corpus, while Perl had the largest language corpus. Scripting languages represented the largest connected network components. The relationship between edges and nodes was linear, though Bioconductor had more edges than expected and Perl had fewer. Spatiotemporal relationships were weak. Most languages shared a bioinformatics specialization and appeared mutualistic or competitive. HIT specializations varied. Specialization was highest for Bioconductor and radiology systems. Specialization and cooperativity were positively correlated among languages but negatively correlated among HIT. Rates of language evolution were similar. Biodiversity among languages grew in the first half of the decade and stabilized, while diversity among HIT was variable but flat. Compared with publications in 2001, correlation with publications one year later was positive while correlation after ten years was weak and negative.Adoption of new technologies can be unpredictable. Spatiotemporal relationships facilitate adoption but are not sufficient. As with ecosystems, dense

  10. Informatics technology mimics ecology: dense, mutualistic collaboration networks are associated with higher publication rates.

    Science.gov (United States)

    Sorani, Marco D

    2012-01-01

    Information technology (IT) adoption enables biomedical research. Publications are an accepted measure of research output, and network models can describe the collaborative nature of publication. In particular, ecological networks can serve as analogies for publication and technology adoption. We constructed network models of adoption of bioinformatics programming languages and health IT (HIT) from the literature.We selected seven programming languages and four types of HIT. We performed PubMed searches to identify publications since 2001. We calculated summary statistics and analyzed spatiotemporal relationships. Then, we assessed ecological models of specialization, cooperativity, competition, evolution, biodiversity, and stability associated with publications.Adoption of HIT has been variable, while scripting languages have experienced rapid adoption. Hospital systems had the largest HIT research corpus, while Perl had the largest language corpus. Scripting languages represented the largest connected network components. The relationship between edges and nodes was linear, though Bioconductor had more edges than expected and Perl had fewer. Spatiotemporal relationships were weak. Most languages shared a bioinformatics specialization and appeared mutualistic or competitive. HIT specializations varied. Specialization was highest for Bioconductor and radiology systems. Specialization and cooperativity were positively correlated among languages but negatively correlated among HIT. Rates of language evolution were similar. Biodiversity among languages grew in the first half of the decade and stabilized, while diversity among HIT was variable but flat. Compared with publications in 2001, correlation with publications one year later was positive while correlation after ten years was weak and negative.Adoption of new technologies can be unpredictable. Spatiotemporal relationships facilitate adoption but are not sufficient. As with ecosystems, dense, mutualistic

  11. Fuzzy Control of Tidal volume, Respiration number and Pressure value

    OpenAIRE

    Hasan Guler; Fikret Ata

    2010-01-01

    In this study, control of tidal volume, respiration number and pressure value which are arrived to patient at mechanical ventilator device which is used in intensive care units were performed with fuzzy logic controller. The aim of this system is to reduce workload of aneshesiologist. By calculating tidal volume, respiration number and pressure value, the error Pe(k) between reference pressure value (Pref) and pressure of gas given ill person (Phasta) and error change rate ;#948;Pe(k) were co...

  12. Occupational Exposure to Respirable Dust, Respirable Crystalline Silica and Diesel Engine Exhaust Emissions in the London Tunnelling Environment.

    Science.gov (United States)

    Galea, Karen S; Mair, Craig; Alexander, Carla; de Vocht, Frank; van Tongeren, Martie

    2016-03-01

    Personal 8-h shift exposure to respirable dust, diesel engine exhaust emissions (DEEE) (as respirable elemental carbon), and respirable crystalline silica of workers involved in constructing an underground metro railway tunnel was assessed. Black carbon (BC) concentrations were also assessed using a MicroAeth AE51. During sprayed concrete lining (SCL) activities in the tunnel, the geometric mean (GM) respirable dust exposure level was 0.91mg m(-3), with the highest exposure measured on a back-up sprayer (3.20mg m(-3)). The GM respirable crystalline silica concentration for SCL workers was 0.03mg m(-3), with the highest measurement also for the back-up sprayer (0.24mg m(-3)). During tunnel boring machine (TBM) activities, the GM respirable dust concentration was 0.54mg m(-3). The GM respirable elemental carbon concentration for all the TBM operators was 18 µg m(-3); with the highest concentration measured on a segment lifter. The BC concentrations were higher in the SCL environment in comparison to the TBM environment (daily GM 18-54 µg m(-3) versus 3-6 µg m(-3)). This small-scale monitoring campaign provides additional personal data on exposures experienced by underground tunnel construction workers. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  13. Microbial respiration per unit microbial biomass increases with carbon-to-nutrient ratios in soils

    Science.gov (United States)

    Spohn, Marie; Chodak, Marcin

    2015-04-01

    The ratio of carbon-to-nutrient in forest floors is usually much higher than the ratio of carbon-to-nutrient that soil microorganisms require for their nutrition. In order to understand how this mismatch affects carbon cycling, the respiration rate per unit soil microbial biomass carbon - the metabolic quotient (qCO2) - was studied. This was done in a field study (Spohn and Chodak, 2015) and in a meta-analysis of published data (Spohn, 2014). Cores of beech, spruce, and mixed spruce-beech forest soils were cut into slices of 1 cm from the top of the litter layer down to 5 cm in the mineral soil, and the relationship between the qCO2 and the soil carbon-to-nitrogen (C:N) and the soil carbon-to-phosphorus (C:P) ratio was analyzed. We found that the qCO2 was positively correlated with soil C:N ratio in spruce soils (R = 0.72), and with the soil C:P ratio in beech (R = 0.93), spruce (R = 0.80) and mixed forest soils (R = 0.96). We also observed a close correlation between the qCO2 and the soil C concentration in all three forest types. Yet, the qCO2 decreased less with depth than the C concentration in all three forest types, suggesting that the change in qCO2 is not only controlled by the soil C concentration. We conclude that microorganisms increase their respiration rate per unit biomass with increasing soil C:P ratio and C concentration, which adjusts the substrate to their nutritional demands in terms of stoichiometry. In an analysis of literature data, I tested the effect of the C:N ratio of soil litter layers on microbial respiration in absolute terms and per unit microbial biomass C. For this purpose, a global dataset on the microbial respiration rate per unit microbial biomass C - termed the metabolic quotient (qCO2) - was compiled form literature data. It was found that the qCO2 in the soil litter layers was positively correlated with the litter C:N ratio and negatively related with the litter nitrogen (N) concentration. The positive relation between the qCO2

  14. Effects of fluoride on mitochondrial activity in higher plants. [Glycine max, Zea mays

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J E; Miller, G W

    1974-01-01

    The effects of fluoride on respiration of plant tissue and mitochondria were investigated. Fumigation of young soybean plants (Glycine max Merr. cm. Hawkeye) with 9-12 ..mu..g x m/sup -3/ HF caused a stimulation of respiration at about 2 days of treatment followed by inhibition 2 days later. Mitochondria isolated from the stimulated tissue had higher respiration rates, greater ATPase activity, and lower P/O ratios, while in mitochondria from inhibited tissue, all three were reduced. Treatment of etiolated soybean hypocotyl sections in Hoagland's solution containing KF for 3 to 10 h only resulted in inhibition of respiration. Mitochondria isolated from this tissue elicited increased respiration rates with malate as substrate and inhibited respiration with succinate. With both substrates respiratory control and ADP/O ratios were decreased. Direct treatment of mitochondria from etiolated soybean hypocotyl tissue with fluoride resulted in inhibition of state 3 respiration and lower ADP/O ratios with the substrates succinate, malate, and NADH. Fluoride was also found to increase the amount of osmotically induced swelling and cause a more rapid leakage of protein with mitochondria isolated from etiolated corn shoots (Zea mays L. cv. Golden Cross Bantam). 40 references, 1 figure, 5 tables.

  15. Implementing a Nitrogen-Based Model for Autotrophic Respiration Using Satellite and Field Observations

    Science.gov (United States)

    Choudhury, Bhaskar J.; Houser, Paul (Technical Monitor)

    2001-01-01

    The rate of carbon accumulation by terrestrial plant communities in a process-level, mechanistic modeling is the difference of the rate of gross photosynthesis by a canopy (A(sub g)) and autotrophic respiration (R) of the stand. Observations for different biomes often show that R to be a large and variable fraction of A(sub g), ca. 35% to 75%, although other studies suggest the ratio of R and A(sub g) to be less variable. Here, R has been calculated according to the two compartment model as being the sum of maintenance and growth components. The maintenance respiration of foliage and living fine roots for different biomes has been determined objectively from observed nitrogen content of these organs. The sapwood maintenance respiration is based on pipe theory, and checked against an independently derived equation considering sapwood biomass and its maintenance coefficient. The growth respiration has been calculated from the difference of A(sub g) and maintenance respiration. The A(sub g) is obtained as the product of biome-specific radiation use efficiency for gross photosynthesis under unstressed conditions and intercepted photosynthetically active radiation, and adjusted for stress. Calculations have been done using satellite and ground observations for 36 consecutive months (1987-1989) over large contiguous areas (ca. 10(exp 5) sq km) of boreal forests, crop land, temperate deciduous forest, temperate grassland, tropical deciduous forest, tropical evergreen forest, tropical savanna, and tundra. The ratio of annual respiration and gross photosynthesis, (R/A(sub g)), is found to be 0.5-0.6 for temperate and cold adopted biome areas, but somewhat higher for tropical biome areas (0.6-0.7). Interannual variation of the fluxes is found to be generally less than 15%. Calculated fluxes are compared with observations and several previous estimates. Results of sensitivity analysis are presented for uncertainties in parameterization and input data. It is found that

  16. Heroin and cocaine abusers have higher discount rates for delayed rewards than alcoholics or non-drug-using controls.

    Science.gov (United States)

    Kirby, Kris N; Petry, Nancy M

    2004-04-01

    To test a prediction of the discounting model of impulsiveness that discount rates would be positively associated with addiction. The delay-discount rate refers to the rate of reduction in the present value of a future reward as the delay to that reward increases. We estimated participants' discount rates on the basis of their pattern of choices between smaller immediate rewards ($11-80) and larger, delayed rewards ($25-85; at delays from 1 week to 6 months) in a questionnaire format. Participants had a one-in-six chance of winning a reward that they chose on one randomly selected trial. Heroin (n = 27), cocaine (n = 41) and alcohol (n = 33) abusers and non-drug-using controls (n = 44) were recruited from advertisements. They were tested in a drug abuse research clinic at a medical school. On average, the cocaine and heroin groups had higher rates than controls (both P rates for heroin abusers (P = 0.03), but not for cocaine or alcohol abusers (both P > 0.50). These data suggest that discount rates vary with the preferred drug of abuse, and that high discount rates should be considered in the development of substance abuse prevention and treatment efforts.

  17. The effect of respiration buffer composition on mitochondrial metabolism and function

    OpenAIRE

    Wollenman, Lucas C.; Vander Ploeg, Matthew R.; Miller, Mackinzie L.; Zhang, Yizhu; Bazil, Jason N.

    2017-01-01

    Functional studies on isolated mitochondria critically rely on the right choice of respiration buffer. Differences in buffer composition can lead to dramatically different respiration rates leading to difficulties in comparing prior studies. The ideal buffer facilities high ADP-stimulated respiratory rates and minimizes substrate transport effects so that the ability to distinguish between various treatments and conditions is maximal. In this study, we analyzed a variety of respiration buffer...

  18. Concerns and perceptions immediately following Superstorm Sandy: ratings for property damage were higher than for health issues.

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael

    Governmental officials, health and safety professionals, early responders, and the public are interested in the perceptions and concerns of people faced with a crisis, especially during and immediately after a disaster strikes. Reliable information can lead to increased individual and community preparedness for upcoming crises. The objective of this research was to evaluate concerns of coastal and central New Jersey residents within the first 100 days of Superstorm Sandy's landfall. Respondents living in central New Jersey and Jersey shore communities were differentially impacted by the storm, with shore residents having higher evacuation rates (47% vs. 13%), more flood waters in their homes, longer power outages (average 23 vs. 6 days), and longer periods without Internet (29 vs. 6 days). Ratings of concerns varied both among and within categories as a function of location (central vs. coastal New Jersey), stressor level (ranging from 1 to 3 for combinations of power outages, high winds, and flooding), and demographics. Respondents were most concerned about property damage, health, inconveniences, ecological services, and nuclear power plants in that order. Respondents from the shore gave higher ratings to the concerns within each major category, compared to those from central Jersey. Four findings have implications for understanding future risk, recovery, and resiliency: (1) respondents with the highest stressor level (level 3) were more concerned about water damage than others, (2) respondents with flood damage were more concerned about water drainage and mold than others, (3) respondents with the highest stressor levels rated all ecological services higher than others, and (4) shore respondents rated all ecological services higher than central Jersey residents. These data provide information to design future preparedness plans, improve resiliency for future severe weather events, and reduce public health risk.

  19. Temperature response of soil respiration largely unaltered with experimental warming

    DEFF Research Database (Denmark)

    Carey, Joanna C; Tang, Jianwu; Templer, Pamela H

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific...... attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies......, spanning nine biomes and over 2 decades of warming. Our analysis reveals no significant differences in the temperature sensitivity of soil respiration between control and warmed plots in all biomes, with the exception of deserts and boreal forests. Thus, our data provide limited evidence of acclimation...

  20. Global variability in leaf respiration in relation to climate and leaf traits

    Science.gov (United States)

    Atkin, Owen K.

    2015-04-01

    Leaf respiration plays a vital role in regulating ecosystem functioning and the Earth's climate. Because of this, it is imperative that that Earth-system, climate and ecosystem-level models be able to accurately predict variations in rates of leaf respiration. In the field of photosynthesis research, the F/vC/B model has enabled modellers to accurately predict variations in photosynthesis through time and space. By contrast, we lack an equivalent biochemical model to predict variations in leaf respiration. Consequently, we need to rely on phenomenological approaches to model variations in respiration across the Earth's surface. Such approaches require that we develop a thorough understanding of how rates of respiration vary among species and whether global environmental gradients play a role in determining variations in leaf respiration. Dealing with these issues requires that data sets be assembled on rates of leaf respiration in biomes across the Earth's surface. In this talk, I will use a newly-assembled global database on leaf respiration and associated traits (including photosynthesis) to highlight variation in leaf respiration (and the balance between respiration and photosynthesis) across global gradients in growth temperature and aridity.

  1. Mitochondrial Respiration and Oxygen Tension.

    Science.gov (United States)

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  2. Respirable versus inhalable dust sampling

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  3. Interpreting, measuring, and modeling soil respiration

    Science.gov (United States)

    Michael G. Ryan; Beverly E. Law

    2005-01-01

    This paper reviews the role of soil respiration in determining ecosystem carbon balance, and the conceptual basis for measuring and modeling soil respiration. We developed it to provide background and context for this special issue on soil respiration and to synthesize the presentations and discussions at the workshop. Soil respiration is the largest component of...

  4. Stimulation of respiration in rat thymocytes induced by ionizing radiation

    International Nuclear Information System (INIS)

    Gudz, T.I.; Pandelova, I.G.; Novgorodov, S.A.

    1994-01-01

    The effect of X irradiation on the respiration of rat thymocytes was studied. An increase in the rate of O 2 uptake was observed 1 h after cells were irradiated with doses of 6-10 Gy. The radiation-induced increase in respiration could be blocked by oligomycin, an inhibitor of mitochondrial ATP synthase, suggesting control by increased cytoplasmic ATP turnover. The stimulation of respiration was not associated with changes in the activity of mitochondrial electron transfer enzymes or permeability of the inner membrane. Several inhibitors of processes which used ATP were screened for their effects on the basal respiration rate and on the radiation response. In irradiated thymocytes, an enhancement of inhibition of respiration by ouabain, La 3+ and cycloheximide was observed. These results indicate that the radiation-induced stimulation of respiration is due to changes in ion homeostasis and protein synthesis. The effect of X irradiation was shown to be independent of the redox status of nonprotein thiols and was not associated with detectable changes in some products of lipid peroxidation. The radiation-induced decrease in activity of superoxide dismutase suggests free radical involvement in deleterious effects of radiation. 43 refs., 2 figs., 3 tabs

  5. Controls on Ecosystem and Root Respiration in an Alaskan Peatland

    Science.gov (United States)

    McConnell, N. A.; McGuire, A. D.; Harden, J. W.; Kane, E. S.; Turetsky, M. R.

    2010-12-01

    Boreal ecosystems cover 14% of the vegetated surface on earth and account for 25-30% of the world’s soil carbon (C), mainly due to large carbon stocks in deep peat and frozen soil layers. While peatlands have served as historical sinks of carbon, global climate change may trigger re-release of C to the atmosphere and may turn these ecosystems into net C sources. Rates of C release from a peatland are determined by regional climate and local biotic and abiotic factors such as vegetation cover, thaw depth, and peat thickness. Soil CO2 fluxes are driven by both autotrophic (plant) respiration and heterotrophic (microbial) respiration. Thus, changes in plant and microbial activity in the soil will impact CO2 emissions from peatlands. In this study, we explored environmental and vegetation controls on ecosystem respiration and root respiration in a variety of wetland sites. The study was conducted at the Alaskan Peatland Experiment (APEX; www.uoguelph.ca/APEX) sites in the Bonanza Creek Experimental Forest located 35 km southwest of Fairbanks Alaska. We measured ecosystem respiration, root respiration, and monitored a suite of environmental variables along a vegetation and soil moisture gradient including a black spruce stand with permafrost, a shrubby site with permafrost, a tussock grass site, and a herbaceous open rich fen. Within the rich fen, we have been conducting water table manipulations including a control, lowered, and raised water table treatment. In each of our sites, we measured total ecosystem respiration using static chambers and root respiration by harvesting roots from the uppermost 20 cm and placing them in a root cuvette to obtain a root flux. Ecosystem respiration (ER) on a μmol/m2/sec basis varied across sites. Water table was a significant predictor of ER at the lowered manipulation site and temperature was a strong predictor at the control site in the rich fen. Water table and temperature were both significant predictors of ER at the raised

  6. Biophysical controls on soil respiration in the dominant patch types of an old-growth, mixed-conifer forest

    Science.gov (United States)

    Siyan Ma; Jiquan Chen; John R. Butnor; Malcolm North; Eugénie S. Euskirchen; Brian Oakley

    2005-01-01

    Little is known about biophysical controls on soil respiration in California's Sierra Nevada old-growth, mixed-conifer forests. Using portable and automated soil respiration sampling units, we measured soil respiration rate (SRR) in three dominant patch types: closed canopy (CC), ceanothus-dominated patches (CECO), and open canopy (OC). SRR varied significantly...

  7. Higher Magnitude Cash Payments Improve Research Follow-up Rates Without Increasing Drug Use or Perceived Coercion

    Science.gov (United States)

    Festinger, David S.; Marlowe, Douglas B.; Dugosh, Karen L.; Croft, Jason R.; Arabia, Patricia L.

    2008-01-01

    In a prior study (Festinger et al., 2005) we found that neither the mode (cash vs. gift card) nor magnitude ($10, $40, or $70) of research follow-up payments increased rates of new drug use or perceptions of coercion. However, higher payments and payments in cash were associated with better follow-up attendance, reduced tracking efforts, and improved participant satisfaction with the study. The present study extended those findings to higher payment magnitudes. Participants from an urban outpatient substance abuse treatment program were randomly assigned to receive $70, $100, $130, or $160 in either cash or a gift card for completing a follow-up assessment at 6 months post-admission (n ≅ 50 per cell). Apart from the payment incentives, all participants received a standardized, minimal platform of follow-up efforts. Findings revealed that neither the magnitude nor mode of payment had a significant effect on new drug use or perceived coercion. Consistent with our previous findings, higher payments and cash payments resulted in significantly higher follow-up rates and fewer tracking calls. In addition participants receiving cash vs. gift cards were more likely to use their payments for essential, non-luxury purchases. Follow-up rates for participants receiving cash payments of $100, $130, and $160 approached or exceeded the FDA required minimum of 70% for studies to be considered in evaluations of new medications. This suggests that the use of higher magnitude payments and cash payments may be effective strategies for obtaining more representative follow-up samples without increasing new drug use or perceptions of coercion. PMID:18395365

  8. Higher dose rate Gamma Knife radiosurgery may provide earlier and longer-lasting pain relief for patients with trigeminal neuralgia.

    Science.gov (United States)

    Lee, John Y K; Sandhu, Sukhmeet; Miller, Denise; Solberg, Timothy; Dorsey, Jay F; Alonso-Basanta, Michelle

    2015-10-01

    Gamma Knife radiosurgery (GKRS) utilizes cobalt-60 as its radiation source, and thus dose rate varies as the fixed source decays over its half-life of approximately 5.26 years. This natural decay results in increasing treatment times when delivering the same cumulative dose. It is also possible, however, that the biological effective dose may change based on this dose rate even if the total dose is kept constant. Because patients are generally treated in a uniform manner, radiosurgery for trigeminal neuralgia (TN) represents a clinical model whereby biological efficacy can be tested. The authors hypothesized that higher dose rates would result in earlier and more complete pain relief but only if measured with a sensitive pain assessment tool. One hundred thirty-three patients were treated with the Gamma Knife Model 4C unit at a single center by a single neurosurgeon during a single cobalt life cycle from January 2006 to May 2012. All patients were treated with 80 Gy with a single 4-mm isocenter without blocking. Using an output factor of 0.87, dose rates ranged from 1.28 to 2.95 Gy/min. The Brief Pain Inventory (BPI)-Facial was administered before the procedure and at the first follow-up office visit 1 month from the procedure (mean 1.3 months). Phone calls were made to evaluate patients after their procedures as part of a retrospective study. Univariate and multivariate linear regression was performed on several independent variables, including sex, age in deciles, diagnosis, follow-up duration, prior surgery, and dose rate. In the short-term analysis (mean 1.3 months), patients' self-reported pain intensity at its worst was significantly correlated with dose rate on multivariate analysis (p = 0.028). Similarly, patients' self-reported interference with activities of daily living was closely correlated with dose rate on multivariate analysis (p = 0.067). A 1 Gy/min decrease in dose rate resulted in a 17% decrease in pain intensity at its worst and a 22% decrease

  9. Theoretical and computational study of the energy dependence of the muon transfer rate from hydrogen to higher-Z gases

    Energy Technology Data Exchange (ETDEWEB)

    Bakalov, Dimitar, E-mail: dbakalov@inrne.bas.bg [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko chaussée 72, Sofia 1784 (Bulgaria); Adamczak, Andrzej [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Stoilov, Mihail [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko chaussée 72, Sofia 1784 (Bulgaria); Vacchi, Andrea [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Via A. Valerio 2, 34127 Trieste (Italy)

    2015-01-23

    The recent PSI Lamb shift experiment and the controversy about proton size revived the interest in measuring the hyperfine splitting in muonic hydrogen as an alternative possibility for comparing ordinary and muonic hydrogen spectroscopy data on proton electromagnetic structure. This measurement critically depends on the energy dependence of the muon transfer rate to heavier gases in the epithermal range. The available data provide only qualitative information, and the theoretical predictions have not been verified. We propose a new method by measurements of the transfer rate in thermalized target at different temperatures, estimate its accuracy and investigate the optimal experimental conditions. - Highlights: • Method for measuring the energy dependence of muon transfer rate to higher-Z gases. • Thermalization and depolarization of muonic hydrogen studied by Monte Carlo method. • Optimal experimental conditions determined by Monte Carlo simulations. • Mathematical model and for estimating the uncertainty of the experimental results.

  10. ATP Production by Respiration and Fermentation, and Energy Charge during Aerobiosis and Anaerobiosis in Twelve Fatty and Starchy Germinating Seeds.

    Science.gov (United States)

    Raymond, P; Al-Ani, A; Pradet, A

    1985-11-01

    The respiration and fermentation rates were compared in germinating seeds of 12 different cultivated species from five families. In air, fermentation contributes significantly to the energy metabolism only in some species (pea, maize), but is generally negligible when compared to respiration. The fermentation rate under anoxia was related either to the metabolic activity under air or to the adenine nucleotide content of the seeds: it was generally higher in seeds which contain starchy reserves (rice, maize, sorghum, pea), than in seeds which do not contain starch (lettuce, sunflower, radish, turnip, cabbage, flax); however, it was similar in wheat, sorghum (starchy seeds), and soya (nonstarchy seeds). The value of the energy charge of all the seeds was lower under anoxia than in air: after 24 hours under anoxia, it was higher than 0.5 in the starchy seeds and in soya and it was around 0.25 in the other fatty seeds.

  11. [Effect of high magnesium ion concentration on the electron transport rate and proton exchange in thylakoid membranes in higher plants].

    Science.gov (United States)

    Ignat'ev, A R; Khorobrykh, S A; Ivanov, B N

    2001-01-01

    The effects of magnesium ion concentration on the rate of electron transport in isolated pea thylakoids were investigated in the pH range from 4.0 up to 8.0. In the absence of magnesium ions in the medium and in the presence of 5 mM MgCl2 in the experiments not only without added artificial acceptors but also with ferricyanide or methylviologen as an acceptor, this rate had a well-expressed maximum at pH 5.0. It was shown that, after depression to minimal values at pH 5.5-6.5, it gradually rose with increasing pH. An increase in magnesium ion concentration up to 20 mM essentially affected the electron transfer rate: it decreased somewhat at pH 4.0-5.0 but increased at higher pH values. At this magnesium ion concentration, the maximum rate was at pH 6.0-6.5 and the minimum, at pH 7.0. Subsequent rise upon increasing pH to 8.0 was expressed more sharply. The influence of high magnesium ion concentration on the rate of electron transport was not observed in the presence of gramicidin D. It was found that without uncoupler, the changes in the electron transfer rate under the influence of magnesium ions correlated to the changes in the first-order rate constant of the proton efflux from thylakoids. It is supposed that the change in the ability of thylakoids to keep protons by the action of magnesium ions is the result of electrostatic interactions of these ions with the charges on the external surface of membranes. A possible role of regulation of the electron transport rate by magnesium ions in vivo is discussed.

  12. Studies on photosynthesis and respiration in some marine macroalgae of the Goa coast

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.

    Primary production and respiration rates were measured in 14 marine macroalgal species from the Goa coast. The highest production rate was observed in Hypnea musciformis and the lowest in Laurencia papillosa. Net production rates in these 14 species...

  13. Does adding metformin to clomifene citrate lead to higher pregnancy rates in a subset of women with polycystic ovary syndrome?

    Science.gov (United States)

    Moll, E; Korevaar, J C; Bossuyt, P M M; van der Veen, F

    2008-08-01

    An RCT among newly diagnosed, therapy naive women with polycystic ovary syndrome (PCOS) showed no significant differences in ovulation rate, ongoing pregnancy rate or spontaneous abortion rate in favour of clomifene citrate plus metformin compared with clomifene citrate. We wanted to assess whether there are specific subgroups of women with PCOS in whom clomifene citrate plus metformin leads to higher pregnancy rates. Subgroup analysis based on clinical and biochemical parameters of 111 women randomized to clomifene citrate plus metformin compared with 114 women randomized to clomifene citrate plus placebo. The data for age, BMI, waist-hip ratio (WHR) and plasma testosterone were available in all women, 2 h glucose in 80% of women and homeostatic model assessment for assessing insulin sensitivity (HOMA) in 50% of women. Of the women who were allocated to the metformin group, 44 women (40%) reached an ongoing pregnancy. In the placebo group, 52 women (46%) reached an ongoing pregnancy. There was a significantly different chance of an ongoing pregnancy for metformin versus placebo between subgroups based on age and WHR (P = 0.014). There was a positive effect of metformin versus placebo on pregnancy rate in older women (>or=28 years) with a high WHR, a negative effect of metformin versus placebo in young women (Metformin may be an effective addition to clomifene citrate in infertile women with PCOS, especially in older and viscerally obese patients.

  14. Improvement of ballistocardiogram processing by inclusion of respiration information

    International Nuclear Information System (INIS)

    Tavakolian, Kouhyar; Vaseghi, Ali; Kaminska, Bozena

    2008-01-01

    In this paper a novel methodology for processing of a ballistocardiogram (BCG) is proposed in which the respiration signal is utilized to improve the averaging of the BCG signal and ultimately the annotation and interpretation of the signal. Previous research works filtered out the respiration signal while the novelty of the current research is that, rather than removing the respiration effect from the signal, we utilize the respiration information to improve the averaging and thus analysis and interpretation of the BCG signal in diagnosis of cardiac malfunctions. This methodology is based on our investigation that BCG cycles corresponding to the inspiration and expiration phases of the respiration cycle are different in morphology. BCG cycles corresponding to the expiration phase of respiration have been proved to be more closely related to each other when compared to cycles corresponding to inspiration, and therefore expiration cycles are better candidates to be selected for the calculation of the averaged BCG signal. The new BCG average calculated based on this methodology is then considered as the representative and a template of the BCG signal for further processing. This template can be considered as the output of a clinical BCG instrument with higher reliability and accuracy compared to the previous processing methods

  15. Tai Chi training reduced coupling between respiration and postural control.

    Science.gov (United States)

    Holmes, Matthew L; Manor, Brad; Hsieh, Wan-hsin; Hu, Kun; Lipsitz, Lewis A; Li, Li

    2016-01-01

    In order to maintain stable upright stance, the postural control system must account for the continuous perturbations to the body's center-of-mass including those caused by spontaneous respiration. Both aging and disease increase "posturo-respiratory synchronization;" which reflects the degree to which respiration affects postural sway fluctuations over time. Tai Chi training emphasizes the coordination of respiration and bodily movements and may therefore optimize the functional interaction between these two systems. The purpose of the project was to examine the effect of Tai Chi training on the interaction between respiration and postural control in older adults. We hypothesized that Tai Chi training would improve the ability of the postural control system to compensate for respiratory perturbations and thus, reduce posturo-respiratory synchronization. Participants were recruited from supportive housing facilities and randomized to a 12-week Tai Chi intervention (n=28; 86 ± 5 yrs) or educational-control program (n=34, 85 ± 6 yrs). Standing postural sway and respiration were simultaneously recorded with a force plate and respiratory belt under eyes-open and eyes-closed conditions. Posturo-respiratory synchronization was determined by quantifying the variation of the phase relationship between the dominant oscillatory mode of respiration and corresponding oscillations within postural sway. Groups were similar in age, gender distribution, height, body mass, and intervention compliance. Neither intervention altered average sway speed, sway magnitude or respiratory rate. As compared to the education-control group, however, Tai Chi training reduced posturo-respiratory synchronization when standing with eyes open or closed (ppostural control or respiration, yet reduced the coupling between respiration and postural control. The beneficial effects of Tai Chi training may therefore stem in part from optimization of this multi-system interaction. Copyright © 2015

  16. Relations between soil respiration, humus quali­ty and ca­tion exchange capacity in selected subtypes of chernozem in South Moravia region

    Directory of Open Access Journals (Sweden)

    Jiřina Foukalová

    2008-01-01

    Full Text Available Soil organic matter (SOM undergoes short and long-term transformation in the soil. Microorganisms through their enzymes are able to mineralize organic carbon while the rate of this process is different. Biological test though referred to one of the main diagnostic methods for evaluating soil qualit­y/health. The aim of our work was to determine basal respiration, total carbon content, fractio­nal composition of humus and basic parameters of soil colloidal complex in selected subtypes of chernozem in South Moravia region. Basal respiration was measured using Vaisala GMT220 apparatus. Total carbon content was determined by oxidimetric titration and basic parameters of soil colloidal according to Mehlich. Results showed that production of carbon dioxide varied from 0.09 to 0.27 mg CO2/100g/h. Linear correlation between basal respiration and humification degree was found. Humus content varied from 2.15% to 4.6%. No correlation between quantity of humus and basal respiration was observed. Higher values of basal respiration were connected with higher quality of HS. Significant linear correlation between total carbon content (TOC and cation exchange capacity (CEC was found.

  17. Dynamic characteristics of soil respiration in Yellow River Delta wetlands, China

    Science.gov (United States)

    Wang, Xiao; Luo, Xianxiang; Jia, Hongli; Zheng, Hao

    2018-02-01

    The stable soil carbon (C) pool in coastal wetlands, referred to as "blue C", which has been extensively damaged by climate change and soil degradation, is of importance to maintain global C cycle. Therefore, to investigate the dynamic characteristics of soil respiration rate and evaluate C budgets in coastal wetlands are urgently. In this study, the diurnal and seasonal variation of soil respiration rate in the reed wetland land (RL) and the bare wetland land (BL) was measured in situ with the dynamic gas-infrared CO2 method in four seasons, and the factors impacted on the dynamic characteristics of soil respiration were investigated. The results showed that the diurnal variation of soil respiration rate consistently presented a "U" curve pattern in April, July, and September, with the maximum values at 12:00 a.m. and the minimum values at 6:00 a.m. In the same season, the diurnal soil respiration rate in RL was significantly greater than those in BL (P respiration rate was 0.14, 0.42, and 0.39 μmol m-2 s-1 in RL, 0.05, 0.22, 0.13, and 0.01 μmol m-2 s-1 in BL, respectively. Soil surface temperature was the primary factor that influenced soil respiration, which was confirmed by the exponential positive correlation between the soil respiration rate and soil surface temperature in BL and RL (P respiration, confirming by the significantly negative correlation between soil respiration rate and the content of soluble salt. These results will be useful for understanding the mechanisms underlying soil respiration and elevating C sequestration potential in the coastal wetlands.

  18. Plant growth and respiration re-visited: maintenance respiration defined – it is an emergent property of, not a separate process within, the system – and why the respiration : photosynthesis ratio is conservative

    Science.gov (United States)

    Thornley, John H. M.

    2011-01-01

    Background and Aims Plant growth and respiration still has unresolved issues, examined here using a model. The aims of this work are to compare the model's predictions with McCree's observation-based respiration equation which led to the ‘growth respiration/maintenance respiration paradigm’ (GMRP) – this is required to give the model credibility; to clarify the nature of maintenance respiration (MR) using a model which does not represent MR explicitly; and to examine algebraic and numerical predictions for the respiration:photosynthesis ratio. Methods A two-state variable growth model is constructed, with structure and substrate, applicable on plant to ecosystem scales. Four processes are represented: photosynthesis, growth with growth respiration (GR), senescence giving a flux towards litter, and a recycling of some of this flux. There are four significant parameters: growth efficiency, rate constants for substrate utilization and structure senescence, and fraction of structure returned to the substrate pool. Key Results The model can simulate McCree's data on respiration, providing an alternative interpretation to the GMRP. The model's parameters are related to parameters used in this paradigm. MR is defined and calculated in terms of the model's parameters in two ways: first during exponential growth at zero growth rate; and secondly at equilibrium. The approaches concur. The equilibrium respiration:photosynthesis ratio has the value of 0·4, depending only on growth efficiency and recycling fraction. Conclusions McCree's equation is an approximation that the model can describe; it is mistaken to interpret his second coefficient as a maintenance requirement. An MR rate is defined and extracted algebraically from the model. MR as a specific process is not required and may be replaced with an approach from which an MR rate emerges. The model suggests that the respiration:photosynthesis ratio is conservative because it depends on two parameters only whose

  19. Does Prison Crowding Predict Higher Rates of Substance Use Related Parole Violations? A Recurrent Events Multi-Level Survival Analysis.

    Directory of Open Access Journals (Sweden)

    Michael A Ruderman

    Full Text Available This administrative data-linkage cohort study examines the association between prison crowding and the rate of post-release parole violations in a random sample of prisoners released with parole conditions in California, for an observation period of two years (January 2003 through December 2004.Crowding overextends prison resources needed to adequately protect inmates and provide drug rehabilitation services. Violence and lack of access to treatment are known risk factors for drug use and substance use disorders. These and other psychosocial effects of crowding may lead to higher rates of recidivism in California parolees.Rates of parole violation for parolees exposed to high and medium levels of prison crowding were compared to parolees with low prison crowding exposure. Hazard ratios (HRs with 95% confidence intervals (CIs were estimated using a Cox model for recurrent events. Our dataset included 13070 parolees in California, combining individual level parolee data with aggregate level crowding data for multilevel analysis.Comparing parolees exposed to high crowding with those exposed to low crowding, the effect sizes from greatest to least were absconding violations (HR 3.56 95% CI: 3.05-4.17, drug violations (HR 2.44 95% CI: 2.00-2.98, non-violent violations (HR 2.14 95% CI: 1.73-2.64, violent and serious violations (HR 1.88 95% CI: 1.45-2.43, and technical violations (HR 1.86 95% CI: 1.37-2.53.Prison crowding predicted higher rates of parole violations after release from prison. The effect was magnitude-dependent and particularly strong for drug charges. Further research into whether adverse prison experiences, such as crowding, are associated with recidivism and drug use in particular may be warranted.

  20. Does Prison Crowding Predict Higher Rates of Substance Use Related Parole Violations? A Recurrent Events Multi-Level Survival Analysis.

    Science.gov (United States)

    Ruderman, Michael A; Wilson, Deirdra F; Reid, Savanna

    2015-01-01

    This administrative data-linkage cohort study examines the association between prison crowding and the rate of post-release parole violations in a random sample of prisoners released with parole conditions in California, for an observation period of two years (January 2003 through December 2004). Crowding overextends prison resources needed to adequately protect inmates and provide drug rehabilitation services. Violence and lack of access to treatment are known risk factors for drug use and substance use disorders. These and other psychosocial effects of crowding may lead to higher rates of recidivism in California parolees. Rates of parole violation for parolees exposed to high and medium levels of prison crowding were compared to parolees with low prison crowding exposure. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a Cox model for recurrent events. Our dataset included 13070 parolees in California, combining individual level parolee data with aggregate level crowding data for multilevel analysis. Comparing parolees exposed to high crowding with those exposed to low crowding, the effect sizes from greatest to least were absconding violations (HR 3.56 95% CI: 3.05-4.17), drug violations (HR 2.44 95% CI: 2.00-2.98), non-violent violations (HR 2.14 95% CI: 1.73-2.64), violent and serious violations (HR 1.88 95% CI: 1.45-2.43), and technical violations (HR 1.86 95% CI: 1.37-2.53). Prison crowding predicted higher rates of parole violations after release from prison. The effect was magnitude-dependent and particularly strong for drug charges. Further research into whether adverse prison experiences, such as crowding, are associated with recidivism and drug use in particular may be warranted.

  1. Does Prison Crowding Predict Higher Rates of Substance Use Related Parole Violations? A Recurrent Events Multi-Level Survival Analysis

    Science.gov (United States)

    Ruderman, Michael A.; Wilson, Deirdra F.; Reid, Savanna

    2015-01-01

    Objective This administrative data-linkage cohort study examines the association between prison crowding and the rate of post-release parole violations in a random sample of prisoners released with parole conditions in California, for an observation period of two years (January 2003 through December 2004). Background Crowding overextends prison resources needed to adequately protect inmates and provide drug rehabilitation services. Violence and lack of access to treatment are known risk factors for drug use and substance use disorders. These and other psychosocial effects of crowding may lead to higher rates of recidivism in California parolees. Methods Rates of parole violation for parolees exposed to high and medium levels of prison crowding were compared to parolees with low prison crowding exposure. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using a Cox model for recurrent events. Our dataset included 13070 parolees in California, combining individual level parolee data with aggregate level crowding data for multilevel analysis. Results Comparing parolees exposed to high crowding with those exposed to low crowding, the effect sizes from greatest to least were absconding violations (HR 3.56 95% CI: 3.05–4.17), drug violations (HR 2.44 95% CI: 2.00–2.98), non-violent violations (HR 2.14 95% CI: 1.73–2.64), violent and serious violations (HR 1.88 95% CI: 1.45–2.43), and technical violations (HR 1.86 95% CI: 1.37–2.53). Conclusions Prison crowding predicted higher rates of parole violations after release from prison. The effect was magnitude-dependent and particularly strong for drug charges. Further research into whether adverse prison experiences, such as crowding, are associated with recidivism and drug use in particular may be warranted. PMID:26492490

  2. Higher Rate of Tuberculosis in Second Generation Migrants Compared to Native Residents in a Metropolitan Setting in Western Europe

    Science.gov (United States)

    Marx, Florian M.; Fiebig, Lena; Hauer, Barbara; Brodhun, Bonita; Glaser-Paschke, Gisela; Haas, Walter

    2015-01-01

    Background In Western Europe, migrants constitute an important risk group for tuberculosis, but little is known about successive generations of migrants. We aimed to characterize migration among tuberculosis cases in Berlin and to estimate annual rates of tuberculosis in two subsequent migrant generations. We hypothesized that second generation migrants born in Germany are at higher risk of tuberculosis compared to native (non-migrant) residents. Methods A prospective cross-sectional study was conducted. All tuberculosis cases reported to health authorities in Berlin between 11/2010 and 10/2011 were eligible. Interviews were conducted using a structured questionnaire including demographic data, migration history of patients and their parents, and language use. Tuberculosis rates were estimated using 2011 census data. Results Of 314 tuberculosis cases reported, 154 (49.0%) participated. Of these, 81 (52.6%) were first-, 14 (9.1%) were second generation migrants, and 59 (38.3%) were native residents. The tuberculosis rate per 100,000 individuals was 28.3 (95CI: 24.0–32.6) in first-, 10.2 (95%CI: 6.1–16.6) in second generation migrants, and 4.6 (95%CI: 3.7–5.6) in native residents. When combining information from the standard notification variables country of birth and citizenship, the sensitivity to detect second generation migration was 28.6%. Conclusions There is a higher rate of tuberculosis among second generation migrants compared to native residents in Berlin. This may be explained by presumably frequent contact and transmission within migrant populations. Second generation migration is insufficiently captured by the surveillance variables country of birth and citizenship. Surveillance systems in Western Europe should allow for quantifying the tuberculosis burden in this important risk group. PMID:26061733

  3. Modified Mitchell osteotomy alone does not have higher rate of residual metatarsalgia than combined first and lesser metatarsal osteotomy

    Directory of Open Access Journals (Sweden)

    Shu-Jung Chen

    2015-04-01

    Full Text Available Transfer metatarsalgia (TM is a common forefoot disorder secondary to hallux valgus (HV. Some authors suggest that a combined lesser metatarsal osteotomy while undergoing HV surgery improves metatarsalgia, whereas others concluded that isolated HV corrective osteotomy can improve symptomatic metatarsalgia. The main purpose of this retrospective study was to compare clinical outcomes in patients with and without combined lesser metatarsal osteotomy while receiving HV correction surgery. We retrospectively reviewed the patients who underwent osteotomy for HV correction between January 2000 and December 2010. All patients underwent HV correction with modified Mitchell osteotomy. Clinical evaluations including the American Orthopaedic Foot and Ankle Society score and residual metatarsalgia were assessed, and radiographic measurements were carried out. Sixty-five patients (83 feet meeting the selection criteria were enrolled. Thirty feet receiving a combined lesser metatarsal osteotomy were classified as the combined surgery (CS group, and the others were classified as the control (CN group (53 feet. The overall rate of persistent symptomatic metatarsalgia was 19.28% after operative treatment. There were six feet with residual metatarsalgia in the CS group, and 10 feet in the CN group. There was no significant difference in the rate of persistent symptoms between the two groups (p = 0.9. According to this result, modified Mitchell osteotomy alone did not have a higher rate of residual metatarsalgia than CS. We also found that the average recovery rate of TM was about 80.7% and those patients whose preoperative HV angle was > 30° had the higher risk of residual metatarsalgia after surgery.

  4. Facepiece leakage and fitting of respirators

    International Nuclear Information System (INIS)

    White, J.M.

    1978-05-01

    The ways in which airborne contaminants can penetrate respirators and the factors which affect the fit of respirators are discussed. The fit of the respirator to the face is shown to be the most critical factor affecting the protection achieved by the user. Qualitative and quantitative fit testing techniques are described and their application to industrial respirator programs is examined. Quantitative measurement of the leakage of a respirator while worn can be used to numerically indicate the protection achieved. These numbers, often referred to as protection factors, are sometimes used as the basis for selecting suitable respirators and this practice is reviewed. (author)

  5. Obese Japanese adults with type 2 diabetes have higher basal metabolic rates than non-diabetic adults.

    Science.gov (United States)

    Miyake, Rieko; Ohkawara, Kazunori; Ishikawa-Takata, Kazuko; Morita, Akemi; Watanabe, Shaw; Tanaka, Shigeho

    2011-01-01

    Several cross-sectional studies in Pima Indians and Caucasians have indicated that obese individuals with type 2 diabetes have a higher basal metabolic rate (BMR) than healthy, obese individuals. However, no study has investigated this comparison in Japanese subjects, who are known to be susceptible to type 2 diabetes due to genetic characteristics. Thirty obese Japanese adults with pre-type 2 diabetes (n=7) or type 2 diabetes (n=13) or without diabetes (n=10) participated in this study. BMR was measured using indirect calorimetry. The relationships between residual BMR (calculated as measured BMR minus BMR adjusted for fat-free mass, fat mass, age, and sex) and biomarkers including fasting glucose, glycosylated hemoglobin (HbA(1c)), fasting insulin, homeostasis model assessment of insulin resistance (HOMA-R), triglycerides, and free fatty acids were examined using Pearson's correlation. BMR in diabetic subjects adjusted for fat-free mass, fat mass, age, and sex was 7.1% higher than in non-diabetic subjects. BMR in diabetic subjects was also significantly (pBMR and fasting glucose (r=0.391, p=0.032). These results indicate that in the Japanese population, obese subjects with type 2 diabetes have higher BMR compared with obese non-diabetic subjects. The fasting glucose level may contribute to these differences.

  6. Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem.

    Science.gov (United States)

    Guan, Chao; Li, Xinrong; Zhang, Peng; Chen, Yongle

    2018-01-01

    Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems.

  7. Dependence of Soil Respiration on Soil Temperature and Soil Moisture in Successional Forests in Southern China

    Institute of Scientific and Technical Information of China (English)

    Xu-Li Tang; Guo-Yi Zhou; Shu-Guang Liu; De-Qiang Zhang; Shi-Zhong Liu; Jiong Li; Cun-Yu Zhou

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (± SD) soil respiration rate in the DNR forests was (9.0±4.6) Mg CO2-C/hm2 per year, ranging from (6.1±3.2) Mg CO2-C/hm2 per year in early successional forests to (10.7±4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  8. Dependence of soil respiration on soil temperature and soil moisture in successional forests in Southern China

    Science.gov (United States)

    Tang, X.-L.; Zhou, G.-Y.; Liu, S.-G.; Zhang, D.-Q.; Liu, S.-Z.; Li, Ji; Zhou, C.-Y.

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (±SD) soil respiration rate in the DNR forests was (9.0 ± 4.6) Mg CO2-C/hm2per year, ranging from (6.1 ± 3.2) Mg CO2-C/hm2per year in early successional forests to (10.7 ± 4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  9. Glycolysis-respiration relationships in a neuroblastoma cell line.

    Science.gov (United States)

    Swerdlow, Russell H; E, Lezi; Aires, Daniel; Lu, Jianghua

    2013-04-01

    Although some reciprocal glycolysis-respiration relationships are well recognized, the relationship between reduced glycolysis flux and mitochondrial respiration has not been critically characterized. We concomitantly measured the extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) of SH-SY5Y neuroblastoma cells under free and restricted glycolysis flux conditions. Under conditions of fixed energy demand ECAR and OCR values showed a reciprocal relationship. In addition to observing an expected Crabtree effect in which increasing glucose availability raised the ECAR and reduced the OCR, a novel reciprocal relationship was documented in which reducing the ECAR via glucose deprivation or glycolysis inhibition increased the OCR. Substituting galactose for glucose, which reduces net glycolysis ATP yield without blocking glycolysis flux, similarly reduced the ECAR and increased the OCR. We further determined how reduced ECAR conditions affect proteins that associate with energy sensing and energy response pathways. ERK phosphorylation, SIRT1, and HIF1a decreased while AKT, p38, and AMPK phosphorylation increased. These data document a novel intracellular glycolysis-respiration effect in which restricting glycolysis flux increases mitochondrial respiration. Since this effect can be used to manipulate cell bioenergetic infrastructures, this particular glycolysis-respiration effect can practically inform the development of new mitochondrial medicine approaches. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Complex terrain alters temperature and moisture limitations of forest soil respiration across a semiarid to subalpine gradient

    Science.gov (United States)

    Berryman, Erin Michele; Barnard, H.R.; Adams, H.R.; Burns, M.A.; Gallo, E.; Brooks, P.D.

    2015-01-01

    Forest soil respiration is a major carbon (C) flux that is characterized by significant variability in space and time. We quantified growing season soil respiration during both a drought year and a nondrought year across a complex landscape to identify how landscape and climate interact to control soil respiration. We asked the following questions: (1) How does soil respiration vary across the catchments due to terrain-induced variability in moisture availability and temperature? (2) Does the relative importance of moisture versus temperature limitation of respiration vary across space and time? And (3) what terrain elements are important for dictating the pattern of soil respiration and its controls? Moisture superseded temperature in explaining watershed respiration patterns, with wetter yet cooler areas higher up and on north facing slopes yielding greater soil respiration than lower and south facing areas. Wetter subalpine forests had reduced moisture limitation in favor of greater seasonal temperature limitation, and the reverse was true for low-elevation semiarid forests. Coincident climate poorly predicted soil respiration in the montane transition zone; however, antecedent precipitation from the prior 10 days provided additional explanatory power. A seasonal trend in respiration remained after accounting for microclimate effects, suggesting that local climate alone may not adequately predict seasonal variability in soil respiration in montane forests. Soil respiration climate controls were more strongly related to topography during the drought year highlighting the importance of landscape complexity in ecosystem response to drought.

  11. General Instructions for Disposable Respirators

    Centers for Disease Control (CDC) Podcasts

    2009-04-09

    This podcast, intended for the general public, demonstrates how to put on and take off disposable respirators that are to be used in areas affected by the influenza outbreak.  Created: 4/9/2009 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 4/29/2009.

  12. Use of Facemasks and Respirators

    Centers for Disease Control (CDC) Podcasts

    2007-05-15

    This program demonstrates the differences of facemasks and respirators that are to be used in public settings during an influenza pandemic.  Created: 5/15/2007 by CDC, National Institute for Occupational Safety and Health (NIOSH).   Date Released: 5/25/2007.

  13. Control of mitochondrial respiration

    NARCIS (Netherlands)

    Tager, J. M.; Wanders, R. J.; Groen, A. K.; Kunz, W.; Bohnensack, R.; Küster, U.; Letko, G.; Böhme, G.; Duszynski, J.; Wojtczak, L.

    1983-01-01

    The control theory of Kacser and Burns [in: Rate Control of Biological Processes (Davies, D.D. ed) pp. 65-104, Cambridge University Press, London, 1973] and Heinrich and Rapoport [Eur. J. Biochem. (1974) 42, 97-105] has been used to quantify the amount of control exerted by different steps on

  14. [Seasonal variation of soil respiration and its components in tropical rain forest and rubber plantation in Xishuangbanna, Yunnan].

    Science.gov (United States)

    Lu, Hua-Zheng; Sha, Li-Qing; Wang, Jun; Hu, Wen-Yan; Wu, Bing-Xia

    2009-10-01

    By using trenching method and infrared gas analyzer, this paper studied the seasonal variation of soil respiration (SR), including root respiration (RR) and heterotrophic respiration (HR), in tropical seasonal rain forest (RF) and rubber (Hevea brasiliensis) plantation (RP) in Xishuangbanna of Yunnan, China. The results showed that the SR and HR rates were significantly higher in RF than in RP (P dry-hot season > foggy season, but the RR rate was rainy season > foggy season > dry-hot season in RF, and foggy season > rainy season > dry-hot season in RP. The contribution of RR to SR in RF (29%) was much lower than that in RP (42%, P < 0.01), while the contribution of HR to SR was 71% in RF and 58% in RP. When the soil temperature at 5 cm depth varied from 12 degrees C to 32 degrees C, the Q10 values for SR, HR, and RR rates were higher in RF than in RP. HR had the highest Q10 value, while RR had the lowest one.

  15. Does the increased air humidity affect soil respiration and carbon stocks?

    Science.gov (United States)

    Kukumägi, Mai; Celi, Luisella; Said-Pullicino, Daniel; Kupper, Priit; Sõber, Jaak; Lõhmus, Krista; Kutti, Sander; Ostonen, Ivika

    2013-04-01

    Climate manipulation experiments at ecosystem-scale enable us to simulate, investigate and predict changes in carbon balance of forest ecosystems. Considering the predicted increase in air humidity and precipitation for northern latitudes, this work aimed at investigating the effect of increased air humidity on soil respiration, distribution of soil organic matter (SOM) among pools having different turnover times, and microbial, fine root and rhizome biomass. The study was carried out in silver birch (Betula pendula Roth.) and hybrid aspen (Populus tremula L. × P. tremuloides Michx.) stands in a Free Air Humidity Manipulation (FAHM) experimental facility containing three humidified (H; on average 7% above current ambient levels since 2008) and three control (C) plots. Soil respiration rates were measured monthly during the growing season using a closed dynamic chamber method. Density fractionation was adopted to separate SOM into two light fractions (free and aggregate-occluded particulate organic matter, fPOM and oPOM respectively), and one heavy fraction (mineral-associated organic matter, MOM). The fine root and rhizome biomass and microbial data are presented for silver birch stands only. In 2011, after 4 growing seasons of humidity manipulation soil organic carbon contents were significantly higher in C plots than H plot (13.5 and 12.5 g C kg-1, respectively), while soil respiration tended to be higher in the latter. Microbial biomass and basal respiration were 13 and 14% higher in H plots than in the C plots, respectively. Twice more fine roots of trees were estimated in H plots, while the total fine root and rhizome biomass (tree + understory) was similar in C and H plots. Fine root turnover was higher for both silver birch and understory roots in H plots. Labile SOM light fractions (fPOM and oPOM) were significantly smaller in H plots with respect to C plots (silver birch and hybrid aspen stands together), whereas no differences were observed in the

  16. 10 CFR Appendix A to Part 20 - Assigned Protection Factors for Respirators a

    Science.gov (United States)

    2010-01-01

    ... internal dose due to inhalation may, in addition, present external exposure hazards at higher... 10 Energy 1 2010-01-01 2010-01-01 false Assigned Protection Factors for Respirators a A Appendix A..., App. A Appendix A to Part 20—Assigned Protection Factors for Respirators a Operating mode Assigned...

  17. Tillage Effects on Soil Properties & Respiration

    Science.gov (United States)

    Rusu, Teodor; Bogdan, Ileana; Moraru, Paula; Pop, Adrian; Duda, Bogdan; Cacovean, Horea; Coste, Camelia

    2015-04-01

    Soil tillage systems can be able to influence soil compaction, water dynamics, soil temperature and soil structural condition. These processes can be expressed as changes of soil microbiological activity, soil respiration and sustainability of agriculture. Objectives of this study were: 1) to assess the effects of tillage systems (Conventional System-CS, Minimum Tillage-MT, No-Tillage-NT) on soil compaction, soil temperature, soil moisture and soil respiration and 2) to establish the relationship that exists in changing soil properties. Three treatments were installed: CS-plough + disc; MT-paraplow + rotary grape; NT-direct sowing. The study was conducted on an Argic-Stagnic Faeoziom. The MT and NT applications reduce or completely eliminate the soil mobilization, due to this, soil is compacted in the first year of application. The degree of compaction is directly related to soil type and its state of degradation. The state of soil compaction diminished over time, tending toward a specific type of soil density. Soil moisture was higher in NT and MT at the time of sowing and in the early stages of vegetation and differences diminished over time. Moisture determinations showed statistically significant differences. The MT and NT applications reduced the thermal amplitude in the first 15 cm of soil depth and increased the soil temperature by 0.5-2.20C. The determinations confirm the effect of soil tillage system on soil respiration; the daily average was lower at NT (315-1914 mmoli m-2s-1) and followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Comparing with CS, all the two conservation tillage measures decreased soil respiration, with the best effects of no-tillage. An exceeding amount of CO2 produced in the soil and released into the atmosphere, resulting from aerobic processes of mineralization of organic matter (excessive loosening) is considered to be not only a way of increasing the CO2 in the atmosphere, but also a loss of

  18. Fatty acid nitroalkenes induce resistance to ischemic cardiac injury by modulating mitochondrial respiration at complex II

    Directory of Open Access Journals (Sweden)

    Jeffrey R. Koenitzer

    2016-08-01

    Full Text Available Nitro-fatty acids (NO2-FA are metabolic and inflammatory-derived electrophiles that mediate pleiotropic signaling actions. It was hypothesized that NO2-FA would impact mitochondrial redox reactions to induce tissue-protective metabolic shifts in cells. Nitro-oleic acid (OA-NO2 reversibly inhibited complex II-linked respiration in isolated rat heart mitochondria in a pH-dependent manner and suppressed superoxide formation. Nitroalkylation of Fp subunit was determined by BME capture and the site of modification by OA-NO2 defined by mass spectrometric analysis. These effects translated into reduced basal and maximal respiration and favored glycolytic metabolism in H9C2 cardiomyoblasts as assessed by extracellular H+ and O2 flux analysis. The perfusion of NO2-FA induced acute cardioprotection in an isolated perfused heart ischemia/reperfusion (IR model as evidenced by significantly higher rate-pressure products. Together these findings indicate that NO2-FA can promote cardioprotection by inducing a shift from respiration to glycolysis and suppressing reactive species formation in the post-ischemic interval.

  19. Effects of inorganic mercury on the respiration and the swimming activity of shrimp larvae, Pandalus borealis

    International Nuclear Information System (INIS)

    St-Amand, L.; Gagnon, R.; Packard, T.T.; Savenkoff, C.

    1999-01-01

    In order to test the sensitivity of respiration (physiological and potential) to mercury (Hg) contamination, larval shrimp Pandalus borealis were exposed to inorganic Hg (0-160 ppb) for 27 h in the laboratory. Oxygen consumption rates (RO 2 ), potential respiration (determined by respiratory electron transfer system activity, ETSA), protein content, and swimming activity for zoeae III and zoeae V stages were measured. For both zoeae stages, ETSA and protein content remained constant after 27 h exposure to 160 ppb Hg whereas RO 2 and swimming activity decreased. This study revealed the impact of different Hg levels and different exposure times on RO 2 of shrimp larvae. After 10 h exposure to 160 ppb Hg, the RO 2 decreased by 43 and 49% in zoeae III and zoeae V stages, respectively. Exposure time of 27 h to 80 ppb Hg and higher, induced paralysis in nearly 100% larvae. Surprisingly, the paralysed larvae displayed almost 50% of the control's RO 2 . The results showed that Hg disturbs a part of the respiration process without modifying the maximum activity of the enzymes involved in the ETSA assay. Therefore, the ETSA assay can not be used as a sublethal bioanalytic probe to detect Hg in short-term exposures. The decline of the RO 2 /ETSA ratios reported here, indicates an inability of contaminated larvae to adapt their metabolism to physiological stress caused by Hg. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. CELL RESPIRATION STUDIES

    Science.gov (United States)

    Daland, Geneva A.; Isaacs, Raphael

    1927-01-01

    1. The oxygen consumption of blood of normal individuals, when the hemoglobin is saturated with oxygen, is practically zero within the limits of experimental error of the microspirometer used. 2. The oxygen consumed in a microspirometer by the blood of patients with chronic myelogenous leucemia with a high white blood cell count, and of one with leucocytosis from sepsis, was proportional to the number of adult polymorphonuclear neutrophils in the blood. 3. No correlation could be made between the rate of oxygen absorption and the total number of white blood cells in the blood, or the total number of immature cells, or the number of red blood cells, or the amount of oxyhemoglobin. 4. The blood of patients with chronic myelogenous leucemia continued to use oxygen in the microspirometer longer than that of normal individuals, and the hemoglobin, in the leucemic bloods, became desaturated even though exposed to air. 5. In blood in which the bulk. of the cells were immature and the mature cells few, the oxygen consumption was lower than in blood in which the mature cells predominated. The rate of oxygen consumption of the immature cells was relatively low as compared to the mature. 6. The slower rate of oxygen absorption by the immature leucocytes in chronic myelogenous leucemia as compared to the mature cells, places them, in accord with Warburg's reports, in the class of the malignant tissues in this respect rather than in the group of young or embryonic cells. PMID:19869329

  1. Video-based respiration monitoring with automatic region of interest detection

    NARCIS (Netherlands)

    Janssen, R.J.M.; Wang, Wenjin; Moço, A.; de Haan, G.

    2016-01-01

    Vital signs monitoring is ubiquitous in clinical environments and emerging in home-based healthcare applications. Still, since current monitoring methods require uncomfortable sensors, respiration rate remains the least measured vital sign. In this paper, we propose a video-based respiration

  2. Soil respiration is not limited by reductions in microbial biomass during long-term soil incubations

    Science.gov (United States)

    Declining rates of soil respiration are reliably observed during long-term laboratory incubations, but the cause is uncertain. We explored different controls on soil respiration during long-term soil incubations. Following a 707 day incubation (30 C) of soils from cultivated and forested plots at Ke...

  3. Soil CO2 concentration does not affect growth or root respiration in bean or citrus

    NARCIS (Netherlands)

    Bouma, T.J.; Nielsen, K.F.; Eissenstat, D.M.; Lynch, J.P.

    1997-01-01

    Contrasting effects of soil CO2 concentration on root respiration rates during short-term CO2 exposure, and on plant growth during long-term CO2 exposure, have been reported, Here we examine the effects of both short-and long-term exposure to soil CO2 on the root respiration of intact plants and on

  4. Is the higher rate of parental child homicide in stepfamilies an effect of non-genetic relatedness?

    Institute of Scientific and Technical Information of China (English)

    Hans TEMRIN; Johanna NORDLUND; Mikael RYING; Birgitta S. TULLBERG

    2011-01-01

    In an evolutionary perspective individuals are expected to vary the degree of parental love and care in relation to the fitness value that a child represents. Hence, stepparents are expected to show less solicitude than genetically related parents, and this lack of genetic relatedness has been used to explain the higher frequencies of child abuse and homicide found in stepfamilies.However, other factors than non-genetic relatedness may cause this over-representation in stepfamilies. Here we use a 45-year data set of parental child homicides in Sweden to test two hypotheses related to the higher incidence in stepfamilies: 1) adults in different types of family differ in their general disposition to use violence, and 2) parents are more likely to kill stepchildren than genetically related children. Of the 152 perpetrators in biparental families there was an overrepresentation of perpetrators in stepfamilies (n=27) compared with the general population. We found support for the first hypothesis in that both general and violent crime rates were higher in stepfamilies, both in the general population and among perpetrators of child homicide. However, we found no support for the second hypothesis because of the 27 perpetrators in stepfamilies the perpetrator killed a genetically related child in 13 cases, a stepchild in 13 cases and both types of children in one case. Moreover, out of the 12 families where the perpetrator lived with both stepchildren and genetic children, there was no bias towards killing stepchildren. Thus, we found no evidence for an effect of non-genetic relatedness per se [Current Zoology 57 (3): 253-59, 2011].

  5. Training in Using Earplugs or Using Earplugs with a Higher than Necessary Noise Reduction Rating? A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    M Salmani Nodoushan

    2014-09-01

    Full Text Available Background: Noise-induced hearing loss (NIHL is one of the most common occupational diseases and the second most common cause of workers' claims for occupational injuries. Objective: Due to high prevalence of NIHL and several reports of improper use of hearing protective devices (HPDs, we conducted this study to compare the effect of face-to-face training in effective use of earplugs with appropriate NRR to overprotection of workers by using earplugs with higher than necessary noise reduction rating (NRR. Methods: In a randomized clinical trial, 150 workers referred to occupational medicine clinic were randomly allocated to three arms—a group wearing earplugs with an NRR of 25 with no training in appropriate use of the device; a group wearing earplugs with an NRR of 25 with training; another group wearing earplugs with an NRR of 30, with no training. Hearing threshold was measured in the study groups by real ear attenuation at threshold (REAT method. This trial is registered with Australian New Zealand clinical trials Registry, number ACTRN00363175. Results: The mean±SD age of the participants was 28±5 (range: 19–39 years. 42% of participants were female. The mean noise attenuation in the group with training was 13.88 dB, significantly higher than those observed in other groups. The highest attenuation was observed in high frequencies (4, 6, and 8 kHz in the group with training. Conclusion: Training in appropriate use of earplugs significantly affects the efficacy of earplugs—even more than using an earplug with higher NRR.

  6. Is the higher rate of parental child homicide in stepfamilies an effect of non-genetic relatedness?

    Directory of Open Access Journals (Sweden)

    Hans TEMRIN, Johanna NORDLUND, Mikael RYING, Birgitta S. TULLBERG

    2011-06-01

    Full Text Available In an evolutionary perspective individuals are expected to vary the degree of parental love and care in relation to the fitness value that a child represents. Hence, stepparents are expected to show less solicitude than genetically related parents, and this lack of genetic relatedness has been used to explain the higher frequencies of child abuse and homicide found in stepfamilies. However, other factors than non-genetic relatedness may cause this over-representation in stepfamilies. Here we use a 45-year data set of parental child homicides in Sweden to test two hypotheses related to the higher incidence in stepfamilies: 1 adults in different types of family differ in their general disposition to use violence, and 2 parents are more likely to kill stepchildren than genetically related children. Of the 152 perpetrators in biparental families there was an overrepresentation of perpetrators in stepfamilies (n=27 compared with the general population. We found support for the first hypothesis in that both general and violent crime rates were higher in stepfamilies, both in the general population and among perpetrators of child homicide. However, we found no support for the second hypothesis because of the 27 perpetrators in stepfamilies the perpetrator killed a genetically related child in 13 cases, a stepchild in 13 cases and both types of children in one case. Moreover, out of the 12 families where the perpetrator lived with both stepchildren and genetic children, there was no bias towards killing stepchildren. Thus, we found no evidence for an effect of non-genetic relatedness per se [Current Zoology 57 (3: 253–259, 2011].

  7. Penetration of asbestos fibers in respirator filters

    International Nuclear Information System (INIS)

    Cheng, Yung-Sung; Pearson, S.D.; Rohrbacher, K.D.; Yeh, Hsu-Chi.

    1994-01-01

    Currently, the health risks associated with asbestos have restricted its use and created a growing asbestos abatement industry with a need for respirator filters that are effective for worker protection. The main purpose of this project is to determine the influence of fiber size, electrostatic charge, and flow rate on the penetration of asbestos fibers in respirator filter cartridges. The study includes four types of filters each tested at two flow rates: the AO-R57A, a dual cartridge HEPA filter tested at 16 and 42.5 L/min; the MSA-S, a dust and mist filter tested at 16 and 42.5 L/min; the MSA-A power filter tested at 32 and 85 L/min; and the 3M-8710, a low-efficiency disposable face mask filter tested at 32 and 85 L/min. The three types of asbestos fibers used (amosite, crocidolite, and chrysotile) ranged in length from 0.04-0.5 μm and in aspect ratio (ratio of length to diameter) from 3 to 60. The fibers were used in both charged and neutralized forms. The results from amosite fibers are reported here

  8. The Offer of Advanced Imaging Techniques Leads to Higher Acceptance Rates for Screening Colonoscopy - a Prospective Study.

    Science.gov (United States)

    Albrecht, Heinz; Gallitz, Julia; Hable, Robert; Vieth, Michael; Tontini, Gian Eugenio; Neurath, Markus Friedrich; Riemann, Jurgen Ferdinand; Neumann, Helmut

    2016-01-01

    Colonoscopy plays a fundamental role in early diagnosis and management of colorectal cancer and requires public and professional acceptance to ensure the ongoing success of screening programs. The aim of the study was to prospectively assess whether patient acceptance rates to undergo screening colonoscopy could be improved by the offer of advanced imaging techniques. Overall, 372 randomly selected patients were prospectively included. A standardized questionnaire was developed that inquired of the patients their knowledge regarding advanced imaging techniques. Second, several media campaigns and information events were organized reporting about advanced imaging techniques, followed by repeated evaluation. After one year the evaluation ended. At baseline, 64% of the patients declared that they had no knowledge about new endoscopic methods. After twelve months the overall grade of information increased significantly from 14% at baseline to 34%. The percentage of patients who decided to undergo colonoscopy because of the offer of new imaging methods also increased significantly from 12% at baseline to 42% after 12 months. Patients were highly interested in the offer of advanced imaging techniques. Knowledge about these techniques could relatively easy be provided using local media campaigns. The offer of advanced imaging techniques leads to higher acceptance rates for screening colonoscopies.

  9. Non-English speakers attend gastroenterology clinic appointments at higher rates than English speakers in a vulnerable patient population

    Science.gov (United States)

    Sewell, Justin L.; Kushel, Margot B.; Inadomi, John M.; Yee, Hal F.

    2009-01-01

    Goals We sought to identify factors associated with gastroenterology clinic attendance in an urban safety net healthcare system. Background Missed clinic appointments reduce the efficiency and availability of healthcare, but subspecialty clinic attendance among patients with established healthcare access has not been studied. Study We performed an observational study using secondary data from administrative sources to study patients referred to, and scheduled for an appointment in, the adult gastroenterology clinic serving the safety net healthcare system of San Francisco, California. Our dependent variable was whether subjects attended or missed a scheduled appointment. Analysis included multivariable logistic regression and classification tree analysis. 1,833 patients were referred and scheduled for an appointment between 05/2005 and 08/2006. Prisoners were excluded. All patients had a primary care provider. Results 683 patients (37.3%) missed their appointment; 1,150 (62.7%) attended. Language was highly associated with attendance in the logistic regression; non-English speakers were less likely than English speakers to miss an appointment (adjusted odds ratio 0.42 [0.28,0.63] for Spanish, 0.56 [0.38,0.82] for Asian language, p gastroenterology clinic appointment, not speaking English was most strongly associated with higher attendance rates. Patient related factors associated with not speaking English likely influence subspecialty clinic attendance rates, and these factors may differ from those affecting general healthcare access. PMID:19169147

  10. 3D versus 2D Systematic Transrectal Ultrasound-Guided Prostate Biopsy: Higher Cancer Detection Rate in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Alexandre Peltier

    2013-01-01

    Full Text Available Objectives. To compare prostate cancer detection rates of extended 2D versus 3D biopsies and to further assess the clinical impact of this method in day-to-day practice. Methods. We analyzed the data of a cohort of 220 consecutive patients with no prior history of prostate cancer who underwent an initial prostate biopsy in daily practice due to an abnormal PSA and/or DRE using, respectively, the classical 2D and the new 3D systems. All the biopsies were done by a single experienced operator using the same standardized protocol. Results. There was no significant difference in terms of age, total PSA, or prostate volume between the two groups. However, cancer detection rate was significantly higher using the 3D versus the 2D system, 50% versus 34% (P<0.05. There was no statistically significant difference while comparing the 2 groups in term of nonsignificant cancer detection. Conclusion. There is reasonable evidence demonstrating the superiority of the 3D-guided biopsies in detecting prostate cancers that would have been missed using the 2D extended protocol.

  11. 78 FR 18535 - Respirator Certification Fees

    Science.gov (United States)

    2013-03-27

    ... facepiece respirators. The North American respiratory protection market generated revenues around $1,830 million in 2007, the most recent data available.\\4\\ A summary of market segmentation, by respirator type... management. Of the U.S. respirator market of products approved by NIOSH, approximately 35 percent of approval...

  12. Exposure to inhalable, respirable, and ultrafine particles in welding fume.

    Science.gov (United States)

    Lehnert, Martin; Pesch, Beate; Lotz, Anne; Pelzer, Johannes; Kendzia, Benjamin; Gawrych, Katarzyna; Heinze, Evelyn; Van Gelder, Rainer; Punkenburg, Ewald; Weiss, Tobias; Mattenklott, Markus; Hahn, Jens-Uwe; Möhlmann, Carsten; Berges, Markus; Hartwig, Andrea; Brüning, Thomas

    2012-07-01

    This investigation aims to explore determinants of exposure to particle size-specific welding fume. Area sampling of ultrafine particles (UFP) was performed at 33 worksites in parallel with the collection of respirable particles. Personal sampling of respirable and inhalable particles was carried out in the breathing zone of 241 welders. Median mass concentrations were 2.48 mg m(-3) for inhalable and 1.29 mg m(-3) for respirable particles when excluding 26 users of powered air-purifying respirators (PAPRs). Mass concentrations were highest when flux-cored arc welding (FCAW) with gas was applied (median of inhalable particles: 11.6 mg m(-3)). Measurements of particles were frequently below the limit of detection (LOD), especially inside PAPRs or during tungsten inert gas welding (TIG). However, TIG generated a high number of small particles, including UFP. We imputed measurements welding fume. Concentrations were mainly predicted by the welding process and were significantly higher when local exhaust ventilation (LEV) was inefficient or when welding was performed in confined spaces. Substitution of high-emission techniques like FCAW, efficient LEV, and using PAPRs where applicable can reduce exposure to welding fume. However, harmonizing the different exposure metrics for UFP (as particle counts) and for the respirable or inhalable fraction of the welding fume (expressed as their mass) remains challenging.

  13. Insulin resistance in HIV-infected youth is associated with decreased mitochondrial respiration.

    Science.gov (United States)

    Takemoto, Jody K; Miller, Tracie L; Wang, Jiajia; Jacobson, Denise L; Geffner, Mitchell E; Van Dyke, Russell B; Gerschenson, Mariana

    2017-01-02

    To identify relationships between insulin resistance (IR) and mitochondrial respiration in perinatally HIV-infected youth. Case-control study. Mitochondrial respiration was assessed in perinatally HIV-infected youth in Tanner stages 2-5, 25 youth with IR (IR+) and 50 without IR (IR-) who were enrolled in the Pediatric HIV/AIDS Cohort Study. IR was defined as a homeostatic model of assessment for IR value at least 4.0. A novel, high-throughput oximetry method was used to evaluate cellular respiration in peripheral blood mononuclear cells. Unadjusted and adjusted differences in mitochondrial respiration markers between IR+ and IR- were evaluated, as were correlations between mitochondrial respiration markers and biochemical measurements. IR+ and IR- youth were similar on age, sex, and race/ethnicity. Mean age was 16.5 and 15.6 years in IR+ and IR-, respectively. The IR+ group had significantly higher mean BMI and metabolic analytes (fasting glucose, insulin, cholesterol, triglycerides, and venous lactate and pyruvate) compared with the IR-. Mitochondrial respiration markers were, on average, lower in the IR+ compared with IR-, including basal respiration (417.5 vs. 597.5 pmol, P = 0.074), ATP production (11 513 vs. 15 202 pmol, P = 0.078), proton leak (584.6 vs. 790.0 pmol, P = 0.033), maximal respiration (1815 vs. 2399 pmol, P = 0.025), and spare respiration capacity (1162 vs. 2017 pmol, P = 0.032). Nonmitochondrial respiration did not differ by IR status. The results did not change when adjusted for age. HIV-infected youth with IR have lower mitochondrial respiration markers when compared to youth without IR. Disordered mitochondrial respiration may be a potential mechanism for IR in this population.

  14. Soil Respiration and Bacterial Structure and Function after 17 Years of a Reciprocal Soil Transplant Experiment.

    Science.gov (United States)

    Bond-Lamberty, Ben; Bolton, Harvey; Fansler, Sarah; Heredia-Langner, Alejandro; Liu, Chongxuan; McCue, Lee Ann; Smith, Jeffrey; Bailey, Vanessa

    2016-01-01

    The effects of climate change on soil organic matter-its structure, microbial community, carbon storage, and respiration response-remain uncertain and widely debated. In addition, the effects of climate changes on ecosystem structure and function are often modulated or delayed, meaning that short-term experiments are not sufficient to characterize ecosystem responses. This study capitalized on a long-term reciprocal soil transplant experiment to examine the response of dryland soils to climate change. The two transplant sites were separated by 500 m of elevation on the same mountain slope in eastern Washington state, USA, and had similar plant species and soil types. We resampled the original 1994 soil transplants and controls, measuring CO2 production, temperature response, enzyme activity, and bacterial community structure after 17 years. Over a laboratory incubation of 100 days, reciprocally transplanted soils respired roughly equal cumulative amounts of carbon as non-transplanted controls from the same site. Soils transplanted from the hot, dry, lower site to the cooler and wetter (difference of -5°C monthly maximum air temperature, +50 mm yr-1 precipitation) upper site exhibited almost no respiratory response to temperature (Q10 of 1.1), but soils originally from the upper, cooler site had generally higher respiration rates. The bacterial community structure of transplants did not differ significantly from that of untransplanted controls, however. Slight differences in local climate between the upper and lower Rattlesnake locations, simulated with environmental control chambers during the incubation, thus prompted significant differences in microbial activity, with no observed change to bacterial structure. These results support the idea that environmental shifts can influence soil C through metabolic changes, and suggest that microbial populations responsible for soil heterotrophic respiration may be constrained in surprising ways, even as shorter- and

  15. Effect of nitrogen on the seasonal course of growth and maintenance respiration in stems of Norway spruce trees.

    Science.gov (United States)

    Stockfors, Jan; Linder, Sune

    1998-03-01

    To determine effects of stem nitrogen concentration ([N]) on the seasonal course of respiration, rates of stem respiration of ten control and ten irrigated-fertilized (IL), 30-year-old Norway spruce trees (Picea abies (L.) Karst.), growing in northern Sweden, were measured on seven occasions from June 1993 to April 1994. To explore sources of seasonal variation and mechanisms of fertilization effects on respiration, we separated total respiration into growth and maintenance respiration for both xylem and phloem bark. Stem respiration increased in response to the IL treatment and was positively correlated with growth rate, volume of living cells and stem nitrogen content. However, no significant effect of IL treatment or [N] in the living cells was found for respiration per unit volume of live cells. Total stem respiration during the growing season (June to September) was estimated to be 16.7 and 29.7 mol CO(2) m(-2) for control and IL-treated trees, respectively. Respiration during the growing season accounted for approximately 64% of total annual respiration. Depending on the method, estimated growth respiration varied between 40 and 60% of total respiration during the growing season. Between 75 and 80% of the live cell volume in the stems was in the phloem, and phloem maintenance accounted for about 70% of maintenance respiration. Because most of the living cells were found in the phloem, and the living xylem cells were concentrated in the outer growth rings, we concluded that the best base for expressing rates of stem growth and maintenance respiration in young Norway spruce trees is stem surface area.

  16. Temperature response of soil respiration largely unaltered with experimental warming

    NARCIS (Netherlands)

    Carey, J.C.; Tang, J.; Templer, P.H.; Kroeger, K.D.; Crowther, T.W.; Burton, A.J.; Dukes, J.S.; Emmett, B.; Frey, S.D.; Heskel, M.A.; Jiang, L.; Machmuller, M.B.; Mohan, J.; Panetta, A.M.; Reich, P.B.; Reinsch, S.; Wang, X.; Allison, S.D.; Bamminger, C.; Bridgham, S.; Collins, S.L.; de Dato, G.; Eddy, W.C.; Enquist, B.J.; Estiarte, M.; Harte, J.; Henderson, A.; Johnson, B.R.; Larsen, K.S.; Luo, Y.; Marhan, S.; Melillo, J.M.; Peñuelas, J.; Pfeifer-Meister, L.; Poll, C.; Rastetter, E.; Reinmann, A.B.; Reynolds, L.L.; Schmidt, I.K.; Shaver, G.R.; Strong, A.L.; Suseela, V.; Tietema, A.

    2016-01-01

    The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific

  17. Hydrological controls on heterotrophic soil respiration across an agricultural landscape

    Science.gov (United States)

    Water availability is an important determinant of variation in soil respiration, but a consistent relationship between soil water and the relative flux rate of carbon dioxide across different soil types remains elusive. Using large undisturbed soil columns (N = 12), we evaluated soil water controls...

  18. Respiration shutoff in Escherichia coli K12 strains is induced by far ultraviolet radiations and by mitomycin C

    International Nuclear Information System (INIS)

    Swenson, P.A.; Norton, I.L.

    1984-01-01

    Near ultraviolet radiations (UV) cause respiration to shutoff in Escherichia coli B/r. It has been reported that E. coli K12 strains do not shut off respiration after UV. It is also reported that mitomycin C did not cause this 'SOS' response. In this paper it is reported that higher UV fluences than were previously used will cause respiration shutoff in K12 strain W3110 and that cyclic AMP increases the sensitivity of respiration shutoff of irradiated cell suspensions. Also mitomycin C shuts off respiration in this strain. Neither UV nor mitomycin C causes respiration shutoff in the recA56 derivative of W3110. Thus respiration shutoff is a recA dependent response to UV and mitomycin C in E. coli K12 strains. (Auth.)

  19. SU-E-J-67: Evaluation of Breathing Patterns for Respiratory-Gated Radiation Therapy Using Respiration Regularity Index

    International Nuclear Information System (INIS)

    Cheong, K; Lee, M; Kang, S; Yoon, J; Park, S; Hwang, T; Kim, H; Kim, K; Han, T; Bae, H

    2014-01-01

    Purpose: Despite the importance of accurately estimating the respiration regularity of a patient in motion compensation treatment, an effective and simply applicable method has rarely been reported. The authors propose a simple respiration regularity index based on parameters derived from a correspondingly simplified respiration model. Methods: In order to simplify a patient's breathing pattern while preserving the data's intrinsic properties, we defined a respiration model as a power of cosine form with a baseline drift. According to this respiration formula, breathing-pattern fluctuation could be explained using four factors: sample standard deviation of respiration period, sample standard deviation of amplitude and the results of simple regression of the baseline drift (slope and standard deviation of residuals of a respiration signal. Overall irregularity (δ) was defined as a Euclidean norm of newly derived variable using principal component analysis (PCA) for the four fluctuation parameters. Finally, the proposed respiration regularity index was defined as ρ=ln(1+(1/ δ))/2, a higher ρ indicating a more regular breathing pattern. Subsequently, we applied it to simulated and clinical respiration signals from real-time position management (RPM; Varian Medical Systems, Palo Alto, CA) and investigated respiration regularity. Moreover, correlations between the regularity of the first session and the remaining fractions were investigated using Pearson's correlation coefficient. Results: The respiration regularity was determined based on ρ; patients with ρ 0.7 was suitable for respiratory-gated radiation therapy (RGRT). Fluctuations in breathing cycle and amplitude were especially determinative of ρ. If the respiration regularity of a patient's first session was known, it could be estimated through subsequent sessions. Conclusions: Respiration regularity could be objectively determined using a respiration regularity index, ρ. Such single-index testing of

  20. Action of γ-rays on the respiration and growth of perilla

    International Nuclear Information System (INIS)

    Sergeeva, E.A.

    1976-01-01

    The respiration rate of leaves of different stroyes and the growth rate of the main steam of perilla plants have been studied after irradiation with γ-rays (3 and 6 kR). Three periods have been distinguished in the rate of the processes under study. The growth and respiration were inhibited in the initial post-irradiation period, then their rate increased till it exceeded the control values at the end of the restoration period. During the subsequent third period, the rate of growth and respiration processes decreased reaching the values observed in unirradiated plants. Changes in the radiosensitive process of growth of irradiated plants are suggested to be the cause for changes in the respiration rate

  1. HIV positivity but not HPV/p16 status is associated with higher recurrence rate in anal cancer.

    Science.gov (United States)

    Meyer, Joshua E; Panico, Vinicius J A; Marconato, Heloisa M F; Sherr, David L; Christos, Paul; Pirog, Edyta C

    2013-12-01

    .06). The regional and distant failure rate was not related to HPV/p16 positivity or histologic differentiation of ACA; however, HIV positivity appeared to be associated with a higher recurrence rate and worse recurrence-free survival.

  2. Satellite telemetry reveals higher fishing mortality rates than previously estimated, suggesting overfishing of an apex marine predator.

    Science.gov (United States)

    Byrne, Michael E; Cortés, Enric; Vaudo, Jeremy J; Harvey, Guy C McN; Sampson, Mark; Wetherbee, Bradley M; Shivji, Mahmood

    2017-08-16

    Overfishing is a primary cause of population declines for many shark species of conservation concern. However, means of obtaining information on fishery interactions and mortality, necessary for the development of successful conservation strategies, are often fisheries-dependent and of questionable quality for many species of commercially exploited pelagic sharks. We used satellite telemetry as a fisheries-independent tool to document fisheries interactions, and quantify fishing mortality of the highly migratory shortfin mako shark ( Isurus oxyrinchus ) in the western North Atlantic Ocean. Forty satellite-tagged shortfin mako sharks tracked over 3 years entered the Exclusive Economic Zones of 19 countries and were harvested in fisheries of five countries, with 30% of tagged sharks harvested. Our tagging-derived estimates of instantaneous fishing mortality rates ( F = 0.19-0.56) were 10-fold higher than previous estimates from fisheries-dependent data (approx. 0.015-0.024), suggesting data used in stock assessments may considerably underestimate fishing mortality. Additionally, our estimates of F were greater than those associated with maximum sustainable yield, suggesting a state of overfishing. This information has direct application to evaluations of stock status and for effective management of populations, and thus satellite tagging studies have potential to provide more accurate estimates of fishing mortality and survival than traditional fisheries-dependent methodology. © 2017 The Author(s).

  3. Water Exchange Produces Significantly Higher Adenoma Detection Rate Than Water Immersion: Pooled Data From 2 Multisite Randomized Controlled Trials.

    Science.gov (United States)

    Leung, Felix W; Koo, Malcolm; Cadoni, Sergio; Falt, Premysl; Hsieh, Yu-Hsi; Amato, Arnaldo; Erriu, Matteo; Fojtik, Petr; Gallittu, Paolo; Hu, Chi-Tan; Leung, Joseph W; Liggi, Mauro; Paggi, Silvia; Radaelli, Franco; Rondonotti, Emanuele; Smajstrla, Vit; Tseng, Chih-Wei; Urban, Ondrej

    2018-03-02

    To test the hypothesis that water exchange (WE) significantly increases adenoma detection rates (ADR) compared with water immersion (WI). Low ADR was linked to increased risk for interval colorectal cancers and related deaths. Two recent randomized controlled trials of head-to-head comparison of WE, WI, and traditional air insufflation (AI) each showed that WE achieved significantly higher ADR than AI, but not WI. The data were pooled from these 2 studies to test the above hypothesis. Two trials (5 sites, 14 colonoscopists) that randomized 1875 patients 1:1:1 to AI, WI, or WE were pooled and analyzed with ADR as the primary outcome. The ADR of AI (39.5%) and WI (42.4%) were comparable, significantly lower than that of WE (49.6%) (vs. AI P=0.001; vs. WI P=0.033). WE insertion time was 3 minutes longer than that of AI (Prate (vs. AI) of the >10 mm advanced adenomas. Right colon combined advanced and sessile serrated ADR of AI (3.4%) and WI (5%) were comparable and were significantly lower than that of WE (8.5%) (vs. AI P<0.001; vs. WI P=0.039). Compared with AI and WI, the superior ADR of WE offsets the drawback of a significantly longer insertion time. For quality improvement focused on increasing adenoma detection, WE is preferred over WI. The hypothesis that WE could lower the risk of interval colorectal cancers and related deaths should be tested.

  4. Temperature and substrate controls on intra-annual variation in ecosystem respiration in two subarctic vegetation types

    DEFF Research Database (Denmark)

    Grogan, Paul; Jonasson, Sven Evert

    2005-01-01

    significantly to ecosystem respiration during most phases of winter and summer in the two vegetation types. Ecosystem respiration rates through the year did not differ significantly between vegetation types despite substantial differences in biomass pools, soil depth and temperature regime. Most (76...... contributions of bulk soil organic matter and plant-associated carbon pools to ecosystem respiration is critical to predicting the response of arctic ecosystem net carbon balance to climate change. In this study, we determined the variation in ecosystem respiration rates from birch forest understory and heath......-92%) of the intra-annual variation in ecosystem respiration rates from these two common mesic subarctic ecosystems was explained using a first-order exponential equation relating respiration to substrate chemical quality and soil temperature. Removal of plants and their current year's litter significantly reduced...

  5. Planktonic production and respiration in a subtropical lake dominated by Cyanobacteria.

    Science.gov (United States)

    Tonetta, D; Laudares-Silva, R; Petrucio, M M

    2015-05-01

    Planktonic primary production and respiration rates were estimated in a subtropical coastal lake dominated by Cyanobacteria in order to investigate the temporal and vertical variation in this lake and to evaluate its relationships with limnological variables and phytoplankton. Light and dark bottles were incubated at four different depths in the central part of the lake and were performed bimonthly from June/2009 to December/2010. No significant difference was evident among depths in relation to phytoplankton, limnological variables and metabolic rates. However, the highest production rates were recorded at the surface, and decreased towards the bottom, coupled with phytoplanktonic photosynthetic capacity. Wind induced mixing in Peri Lake played an important role in nutrient and phytoplankton redistribution, characterizing this lake as polymictic. According to density and biovolume, the phytoplankton community was dominated by filamentous Cyanobacteria, especially Cylindrospermopsis raciborskii (Woloszynska) Seenayya and Subba-Raju. This study has shown that both water temperature and nutrient availability drive phytoplankton growth and consequently the temporal variation in metabolic rates, where respiration is higher than primary production.

  6. Planktonic production and respiration in a subtropical lake dominated by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    D. Tonetta

    Full Text Available Planktonic primary production and respiration rates were estimated in a subtropical coastal lake dominated by Cyanobacteria in order to investigate the temporal and vertical variation in this lake and to evaluate its relationships with limnological variables and phytoplankton. Light and dark bottles were incubated at four different depths in the central part of the lake and were performed bimonthly from June/2009 to December/2010. No significant difference was evident among depths in relation to phytoplankton, limnological variables and metabolic rates. However, the highest production rates were recorded at the surface, and decreased towards the bottom, coupled with phytoplanktonic photosynthetic capacity. Wind induced mixing in Peri Lake played an important role in nutrient and phytoplankton redistribution, characterizing this lake as polymictic. According to density and biovolume, the phytoplankton community was dominated by filamentous Cyanobacteria, especially Cylindrospermopsis raciborskii (Woloszynska Seenayya and Subba-Raju. This study has shown that both water temperature and nutrient availability drive phytoplankton growth and consequently the temporal variation in metabolic rates, where respiration is higher than primary production.

  7. Cardiac, skeletal, and smooth muscle mitochondrial respiration: are all mitochondria created equal?

    Science.gov (United States)

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I; Trinity, Joel D; Hyngstrom, John R; Garten, Ryan S; Diakos, Nikolaos A; Ives, Stephen J; Dela, Flemming; Larsen, Steen; Drakos, Stavros; Richardson, Russell S

    2014-08-01

    Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial respiration. Therefore, the present study examined mitochondrial respiratory rates in smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscles. Cardiac, skeletal, and smooth muscles were harvested from a total of 22 subjects (53 ± 6 yr), and mitochondrial respiration was assessed in permeabilized fibers. Complex I + II, state 3 respiration, an index of oxidative phosphorylation capacity, fell progressively from cardiac to skeletal to smooth muscles (54 ± 1, 39 ± 4, and 15 ± 1 pmol·s(-1)·mg(-1), P respiration rates were normalized by CS (respiration per mitochondrial content), oxidative phosphorylation capacity was no longer different between the three muscle types. Interestingly, complex I state 2 normalized for CS activity, an index of nonphosphorylating respiration per mitochondrial content, increased progressively from cardiac to skeletal to smooth muscles, such that the respiratory control ratio, state 3/state 2 respiration, fell progressively from cardiac to skeletal to smooth muscles (5.3 ± 0.7, 3.2 ± 0.4, and 1.6 ± 0.3 pmol·s(-1)·mg(-1), P respiration highlight the existence of intrinsic functional differences between these muscle mitochondria. This likely influences the efficiency of oxidative phosphorylation and could potentially alter ROS production.

  8. Estimate of respiration rate and physicochemical changes of fresh-cut apples stored under different temperatures Estimativa da taxa de respiração e das mudanças físico-químicas de maçãs minimamente processadas e estocadas sob diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Cristiane Fagundes

    2013-03-01

    Full Text Available In this study, the influence of storage temperature and passive modified packaging (PMP on the respiration rate and physicochemical properties of fresh-cut Gala apples (Malus domestica B. was investigated. The samples were packed in flexible multilayer bags and stored at 2 °C, 5 °C, and 7 °C for eleven days. Respiration rate as a function of CO2 and O2 concentrations was determined using gas chromatography. The inhibition parameters were estimated using a mathematical model based on Michaelis-Menten equation. The following physicochemical properties were evaluated: total soluble solids, pH, titratable acidity, and reducing sugars. At 2 °C, the maximum respiration rate was observed after 150 hours. At 5 °C and 7 °C the maximum respiration rates were observed after 100 and 50 hours of storage, respectively. The inhibition model results obtained showed a clear effect of CO2 on O2 consumption. The soluble solids decreased, although not significantly, during storage at the three temperatures studied. Reducing sugars and titratable acidity decreased during storage and the pH increased. These results indicate that the respiration rate influenced the physicochemical properties.Neste estudo, a influência da temperatura de armazenamento e da embalagem com atmosfera modificada passiva (AMP na taxa respiratória e nas propriedades físico-químicas de maçãs da variedade Gala (Malus domestica, B. minimamente processadas foi investigada. As amostras foram acondicionadas em embalagens flexíveis e armazenados a 2 °C, 5 °C e 7 °C, durante 11 dias. A taxa de respiração foi gerada para diferentes concentrações de O2 e CO2, obtidas por cromatografia gasosa. Os parâmetros de inibição foram estimados por um modelo matemático baseado na equação de Michaelis-Menten. Foram avaliadas as seguintes propriedades físico-químicas: sólidos solúveis totais, pH, acidez titulável e açúcares redutores. A 2 °C, a taxa de respiração máxima foi

  9. Lymphocyte respiration in children with Trisomy 21

    Directory of Open Access Journals (Sweden)

    Aburawi Elhadi H

    2012-12-01

    Full Text Available Abstract Background This study measured lymphocyte mitochondrial O2 consumption (cellular respiration in children with trisomy 21. Methods Peripheral blood mononuclear cells were isolated from whole blood of trisomy 21 and control children and these cells were immediately used to measure cellular respiration rate. [O2] was determined as a function of time from the phosphorescence decay rates (1/τ of Pd (II-meso-tetra-(4-sulfonatophenyl-tetrabenzoporphyrin. In sealed vials containing lymphocytes and glucose as a respiratory substrate, [O2] declined linearly with time, confirming the zero-order kinetics of O2 conversion to H2O by cytochrome oxidase. The rate of respiration (k, in μM O2 min-1, thus, was the negative of the slope of [O2] vs. time. Cyanide inhibited O2 consumption, confirming that oxidation occurred in the mitochondrial respiratory chain. Results For control children (age = 8.8 ± 5.6 years, n = 26, the mean (± SD value of kc (in μM O2 per min per 107 cells was 1.36 ± 0.79 (coefficient of variation, Cv = 58%; median = 1.17; range = 0.60 to 3.12; -2SD = 0.61. For children with trisomy 21 (age = 7.2 ± 4.6 years, n = 26, the values of kc were 0.82 ± 0.62 (Cv = 76%; median = 0.60; range = 0.20 to 2.80, pp6.1 mU/L. Fourteen of 26 (54% children with trisomy 21 had kc values of 0.20 to 0.60 (i.e., kc positively correlated with body-mass index (BMI, R >0.302, serum creatinine (R >0.507, blood urea nitrogen (BUN, R >0.535 and albumin (R >0.446. Conclusions Children with trisomy 21 in this study have reduced lymphocyte bioenergetics. The clinical importance of this finding requires further studies.

  10. International comparisons of preterm birth: higher rates of late preterm birth are associated with lower rates of stillbirth and neonatal death.

    Science.gov (United States)

    Lisonkova, S; Sabr, Y; Butler, B; Joseph, K S

    2012-12-01

    To examine international rates of preterm birth and potential associations with stillbirths and neonatal deaths at late preterm and term gestation. Ecological study. Canada, USA and 26 countries in Europe. All deliveries in 2004. Information on preterm birth (Statistics Canada, the EURO-PERISTAT project and the National Center for Health Statistics. Pearson correlation coefficients and random-intercept Poisson regression were used to examine the association between preterm birth rates and gestational age-specific stillbirth and neonatal death rates. Rate ratios with 95% confidence intervals were estimated after adjustment for maternal age, parity and multiple births. Stillbirths and neonatal deaths ≥ 32 and ≥ 37 weeks of gestation. International rates of preterm birth (births. Preterm birth rates at 32-36 weeks were inversely associated with stillbirths at ≥ 32 weeks (adjusted rate ratio 0.94, 95% CI 0.92-0.96) and ≥ 37 weeks (adjusted rate ratio 0.88, 95% CI 0.85-0.91) of gestation and inversely associated with neonatal deaths at ≥ 32 weeks (adjusted rate ratio 0.88, 95% CI 0.85-0.91) and ≥ 37 weeks (adjusted rate ratio 0.82, 95% CI 0.78-0.86) of gestation. Countries with high rates of preterm birth at 32-36 weeks of gestation have lower stillbirth and neonatal death rates at and beyond 32 weeks of gestation. Contemporary rates of preterm birth are indicators of both perinatal health and obstetric care services. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

  11. Influence of temperature and organic matter content on soil respiration in a deciduous oak forest

    Directory of Open Access Journals (Sweden)

    Zsolt Kotroczó

    2014-12-01

    Full Text Available The increasing temperature enhances soil respiration differently depend on different conditions (soil moisture, soil organic matter, the activity of soil microbes. It is an essential factor to predicting the effect of climate change on soil respiration. In a temperate deciduous forest (North-Hungary we added or removal aboveground and belowground litter to determine total soil respiration. We investigated the relationship between total soil CO2 efflux, soil moisture and soil temperature. Soil CO2 efflux was measured at each plot using chamber based soil respiration measurements. We determined the temperature sensitivity of soil respiration. The effect of doubled litter was less than the effect of removal. We found that temperature was more influential in the control of soil respiration than soil moisture in litter removal treatments, particularly in the wetter root exclusion treatments (NR and NI (R2: 0.49-0.61. Soil moisture (R2: 0.18-0.24 and temperature (R2: 0.18-0.20 influenced soil respiration similarly in treatments, where soil was drier (Control, Double Litter, Double Wood. A significantly greater increase in temperature induced higher soil respiration were significantly higher (2-2.5-fold in root exclusion treatments, where soil was wetter throughout the year, than in control and litter addition treatments. The highest bacterial and fungal count was at the DL treatment but the differences is not significant compared to the Control. The bacterial number at the No Litter, No Root, No Input treatment was significantly lower at the Control. Similar phenomenon can be observed at the fungal too, but the differences are not significant. The results of soil respiration suggest that the soil aridity can reduce soil respiration increases with the temperature increase. Soil bacterial and fungal count results show the higher organic matter content and soil surface cover litter favors the activity.

  12. Thermal Acclimation of Photosynthesis and Respiration Differ Across Mature Conifer Species in a Boreal Forest Peatland

    Science.gov (United States)

    Dusenge, M. E.; Stinziano, J. R.; Warren, J.; Ward, E. J.; Wullschleger, S.; Hanson, P. J.; Way, D.

    2017-12-01

    Boreal forests are often assumed to be temperature-limited, and warming is therefore expected to stimulate their carbon uptake. However, much of our information on the ability of boreal conifers to acclimate photosynthesis and respiration to rising temperatures comes from seedlings. We measured net CO2 assimilation rates (A) and dark respiration (R) at 25 °C (A25 and R25) and at prevailing growth temperatures (Ag and Rg) in mature Picea mariana (spruce) and Larix laricina (tamarack) exposed to ambient, +2.25, +4.5, +6.75 and +9 °C warming treatments in open top chambers in the field at the SPRUCE experiment (MN, USA). In spruce, A25 and Ag were similar across plots in May and June. In August, spruce in warmer treatments had higher A25, an effect that was offset by warmer leaf temperatures in the Ag data. In tamarack, A25 was stimulated by warming in both June and August, an effect that was mainly offset by higher leaf temperatures when Ag was assessed in June, while in August, Ag was still slightly higher in the warmest treatments (+6.75 and +9) compared to the ambient plots. In spruce, R25 was enhanced in warm-grown trees in May, but was similar across treatments in June and August, indicating little acclimation of R. Rg slightly increased with warming treatments across the season in spruce. In contrast, R in tamarack thermally acclimated, as R25 decreased with warming. But while this acclimation generated homeostatic Rg in June, Rg in August was still highest in the warmest treatments. Our work suggests that the capacity for thermal acclimation in both photosynthesis and respiration varies among boreal tree species, which may lead to shifts in the performance of these species as the climate warms.

  13. Does adding metformin to clomifene citrate lead to higher pregnancy rates in a subset of women with polycystic ovary syndrome?

    NARCIS (Netherlands)

    Moll, E.; Korevaar, J. C.; Bossuyt, P. M. M.; van der Veen, F.

    2008-01-01

    BACKGROUND: An RCT among newly diagnosed, therapy naive women with polycystic ovary syndrome (PCOS) showed no significant differences in ovulation rate, ongoing pregnancy rate or spontaneous abortion rate in favour of clomifene citrate plus metformin compared with clomifene citrate. We wanted to

  14. Biochar has no effect on soil respiration across Chinese agricultural soils.

    Science.gov (United States)

    Liu, Xiaoyu; Zheng, Jufeng; Zhang, Dengxiao; Cheng, Kun; Zhou, Huimin; Zhang, Afeng; Li, Lianqing; Joseph, Stephen; Smith, Pete; Crowley, David; Kuzyakov, Yakov; Pan, Genxing

    2016-06-01

    Biochar addition to soil has been widely accepted as an option to enhance soil carbon sequestration by introducing recalcitrant organic matter. However, it remains unclear whether biochar will negate the net carbon accumulation by increasing carbon loss through CO2 efflux from soil (soil respiration). The objectives of this study were to address: 1) whether biochar addition increases soil respiration; and whether biochar application rate and biochar type (feedstock and pyrolyzing system) affect soil respiration. Two series of field experiments were carried out at 8 sites representing the main crop production areas in China. In experiment 1, a single type of wheat straw biochar was amended at rates of 0, 20 and 40 tha(-1) in four rice paddies and three dry croplands. In experiment 2, four types of biochar (varying in feedstock and pyrolyzing system) were amended at rates of 0 and 20 tha(-1) in a rice paddy under rice-wheat rotation. Results showed that biochar addition had no effect on CO2 efflux from soils consistently across sites, although it increased topsoil organic carbon stock by 38% on average. Meanwhile, CO2 efflux from soils amended with 40 t of biochar did not significantly higher than soils amended with 20 t of biochar. While the biochars used in Experiment 2 had different carbon pools and physico-chemical properties, they had no effect on soil CO2 efflux. The soil CO2 efflux following biochar addition could be hardly explained by the changes in soil physic-chemical properties and in soil microbial biomass. Thus, we argue that biochar will not negate the net carbon accumulation by increasing carbon loss through CO2 efflux in agricultural soils. Copyright © 2016. Published by Elsevier B.V.

  15. Soil and Root Respiration Under Elevated CO2 Concentrations During Seedling Growth of Pinus sylvestris var. sylvestriformis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil respiration during seedling growth of Pinus sylvestris var. sylvestriformis. During the four growing seasons (May-October) from 1999 to 2003, the seedlings were exposed to elevated concentrations of CO2 in open-top chambers. The total soil respiration and contribution of root respiration were measured using an LI-6400-09 soil CO2 flux chamber on June 15 and October 8, 2003. To separate root respiration from total soil respiration, three PVC cylinders were inserted approximately 30 cm deep into the soil in each chamber. There were marked diurnal changes in air and soil temperatures on June 15. Both the total soil respiration and the soil respiration without roots showed a strong diurnal pattern, increasing from before sunrise to about 14:00in the afternoon and then decreasing before the next sunrise. No increase in the mean total soil respiration and mean soil respiration with roots severed was observed under the elevated CO2 treatments on June 15, 2003, as compared to the open field and control chamber with ambient CO2. However, on October 8, 2003, the total soil respiration and soil respiration with roots severed in the open field were lower than those in the control and elevated CO2 chambers. The mean contribution of root respiration measured on June 15, 2003, ranged from 8.3% to 30.5% and on October 8, 2003,from 20.6% to 48.6%.

  16. Copepod swimming behavior, respiration, and expression of stress-related genes in response to high stocking densities

    DEFF Research Database (Denmark)

    Nilsson, Birgitte; Jakobsen, Hans H.; Stief, Peter

    2017-01-01

    ,000 ind. L−1. Three biological/physiological end-points were studied: swimming behavior, respiration rate and expression level of stress-related genes. None of the elevated densities caused any significant change in swimming behavior, respiration rate or gene expression level. This study suggests...

  17. Effects of respirator use on worker performance

    Energy Technology Data Exchange (ETDEWEB)

    Cardarelli, R. [Yankee Atomic Electric Co., Bolton, MA (United States)

    1995-03-01

    In 1993, EPRI funded Yankee Atomic Electric Company to examine the effects of respirator use on worker efficiency. Phase I of Yankee`s effort was to develop a study design to determine respirator effects. Given success in Phase I, a larger population will be tested to determine if a stasitically significant respirator effect on performance can be measured. This paper summarizes the 1993 EPRI/Yankee Respirator Effects of Pilot Study, and describes the study design for the 1994 EPRI/Yankee Respirator Study to be conducted at the Oyster Creek Nuclear Power Plant. Also described is a summary of respirator effect studies that have been conducted during the last ten (10) years.

  18. Ethanol synthesis and aerobic respiration in the laboratory by leader segments of Douglas-fir seedlings from winter and spring.

    Science.gov (United States)

    Joseph, Gladwin; Kelsey, Rick G

    2004-05-01

    Stem segments from terminal leaders of Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, seedlings were sampled in mid-December when cambial cells were dormant. The residual, debudded leaders were resampled again in early May when the cambium was metabolically active. May stems had higher constitutive ethanol concentrations than December stems. This was not the result of cambial hypoxia generated by rapid spring respiration rates, because when aerobic respiration was stimulated by incubating the stems in air at 30 degrees C ethanol production was induced in December, but not in May. Rapid respiration rates at 30 degrees C may have depleted O(2) supplies and induced ethanol production in December stems because dormant, thick-walled cambial cells may be less permeable to CO(2) and O(2), compared with metabolically active, thin-walled cambial cells in May. December stem segments incubated in a N(2) atmosphere at 30 degrees C synthesized 1.8 times more ethanol than segments from May, most likely because spring growth had reduced the soluble sugars available for fermentation. CO(2) efflux from May stems (after 5.5 h of incubation at 30 degrees C) was equal to December stems per unit volume, but greater than December stems per unit surface area. N(2)-induced ethanol concentrations were positively related with CO(2) efflux per unit volume, indicating that rapidly respiring leaders can maintain rapid fermentation rates, provided soluble sugars are readily available. N(2)-induced ethanol and CO(2) efflux per unit volume declined with increasing leader diameter in both seasons, whereas there were no relationships between CO(2) efflux per unit surface area and diameter. Cambium physiology and phenology influence the induction of fermentation and concentrations of ethanol produced in terminal leaders of Douglas-fir, and probably other conifers as well. This needs to be considered when comparing fermentation among species, or comparing individuals from different seasons, or

  19. Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils

    Directory of Open Access Journals (Sweden)

    Antônio Ocimar Manzi

    2011-04-01

    Full Text Available Central Amazonian rainforest landscape supports a mosaic of tall terra firme rainforest and ecotone campinarana, riparian and campina forests, reflecting topography-induced variations in soil, nutrient and drainage conditions. Spatial and temporal variations in litter decomposition, soil and groundwater chemistry and soil CO2 respiration were studied in forests on sandy soils, whereas drought sensitivity of poorly-drained valley soils was investigated in an artificial drainage experiment. Slightly changes in litter decomposition or water chemistry were observed as a consequence of artificial drainage. Riparian plots did experience higher litter decomposition rates than campina forest. In response to a permanent lowering of the groundwater level from 0.1 m to 0.3 m depth in the drainage plot, topsoil carbon and nitrogen contents decreased substantially. Soil CO2 respiration decreased from 3.7±0.6 µmol m-2 s-1 before drainage to 2.5±0.2 and 0.8±0.1 µmol m-2 s-1 eight and 11 months after drainage, respectively. Soil respiration in the control plot remained constant at 3.7±0.6 µmol m-2 s-1. The above suggests that more frequent droughts may affect topsoil carbon and nitrogen content and soil respiration rates in the riparian ecosystem, and may induce a transition to less diverse campinarana or short-statured campina forest that covers areas with strongly-leached sandy soil.

  20. Evaluation of 14C abundance in soil respiration using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Koarashi, Jun; Iida, Takao; Moriizumi, Jun; Asano, Tomohiro

    2004-01-01

    To clarify the behavior of 14 C in terrestrial ecosystems, 14 C abundance in soil respiration was evaluated in an urban forest with a new method involving a closed chamber technique and 14 C measurement by accelerator mass spectrometry (AMS). Soil respiration had a higher Δ 14 C than the contemporary atmosphere. This indicates that a significant portion of soil respiration is derived from the decomposition of soil organic matter enriched in 14 C by atmospheric nuclear weapons tests, with a notable time lag between atmospheric 14 C addition and re-emission from soil. On the other hand, δ 14 C in soil respiration demonstrated that 14 C abundance ratio itself in soil-respired CO 2 is not always high compared with that in atmospheric CO 2 because of the isotope fractionation during plant photosynthesis and microbial decomposition of soil organic matter. The Δ 14 C in soil respiration was slightly lower in August than in March, suggesting a relatively high contribution of plant root respiration and decomposition of newly accumulated and/or 14 C-depleted soil organic matter to the total soil respiration in August

  1. Respirators: Supervisors Self-Study #43442

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-20

    This course, Respirators: Supervisors Self-Study (#43442), addresses training requirements for supervisors of respirator wearers as specified by the American National Standard Institute (ANSI) Standard for Respiratory Protection, ANSI Z88.2, and as incorporated by reference in the Department of Energy (DOE) Worker Health and Safety Rule, 10 Code of Federal Regulations (CFR) 851. This course also presents the responsibilities of supervisors of respirator wearers at Los Alamos National Laboratory (LANL).

  2. A combination of high dose rate (10X FFF/2400 MU/min/10 MV X-rays) and total low dose (0.5 Gy) induces a higher rate of apoptosis in melanoma cells in vitro and superior preservation of normal melanocytes.

    Science.gov (United States)

    Sarojini, Sreeja; Pecora, Andrew; Milinovikj, Natasha; Barbiere, Joseph; Gupta, Saakshi; Hussain, Zeenathual M; Tuna, Mehmet; Jiang, Jennifer; Adrianzen, Laura; Jun, Jaewook; Catello, Laurice; Sanchez, Diana; Agarwal, Neha; Jeong, Stephanie; Jin, Youngjin; Remache, Yvonne; Goy, Andre; Ndlovu, Alois; Ingenito, Anthony; Suh, K Stephen

    2015-10-01

    The aim of this study was to determine the apoptotic effects, toxicity, and radiosensitization of total low dose irradiation delivered at a high dose rate in vitro to melanoma cells, normal human epidermal melanocytes (HEM), or normal human dermal fibroblasts (HDF) and to study the effect of mitochondrial inhibition in combination with radiation to enhance apoptosis in melanoma cells. Cells irradiated using 10X flattening filter-free (FFF) 10 MV X-rays at a dose rate of 400 or 2400 MU/min and a total dose of 0.25-8 Gy were analyzed by cell/colony counting, MitoTracker, MTT, and DNA-damage assays, as well as by quantitative real-time reverse transcriptase PCR in the presence or absence of mitochondrial respiration inhibitors. A dose rate of 2400 MU/min killed on average five-fold more melanoma cells than a dose rate 400 MU/min at a total dose of 0.5 Gy and preserved 80% survival of HEM and 90% survival of HDF. Increased apoptosis at the 2400 MU/min dose rate is mediated by greater DNA damage, reduced cell proliferation, upregulation of apoptotic genes, and downregulation of cell cycle genes. HEM and HDF were relatively unharmed at 2400 MU/min. Radiation induced upregulation of mitochondrial respiration in both normal and cancer cells, and blocking the respiration with inhibitors enhanced apoptosis only in melanoma cells. A high dose rate with a low total dose (2400 MU/min, 0.5 Gy/10X FFF 10 MV X-rays) enhances radiosensitivity of melanoma cells while reducing radiotoxicity toward HEM and HDF. Selective cytotoxicity of melanoma cells is increased by blocking mitochondrial respiration.

  3. [Soil respiration dynamics and its controlling factors of typical vegetation communities on meadow steppes in the western Songnen Plain].

    Science.gov (United States)

    Wang, Ming; Liu, Xing-Tu; Li, Xiu-Jun; Zhang, Ji-Tao; Wang, Guo-Dong; Lu, Xin-Rui; Li, Xiao-Yu

    2014-01-01

    In order to accurately explore the soil respiration dynamics and its controlling factors of typical vegetation types in the western Songnen Plain, soil respiration rates of Chloris virgata, Puccinellia distans, Phragmites australis and Leymus chinensis communities were measured. The results showed that the diurnal curves of soil respiration rates of the four vegetation communities had simple peak values, which appeared at 11:00-15:00, and the valley values occurred at 21:00-1:00 or 3:00-5:00. The seasonal dynamic patterns of their soil respiration rates were similar, with the maximum (3.21-4.84 micromol CO2 x m(-2) x s(-1)) occurring in July and August and the minimum (0.46-1.51 micromol CO2 x m(-2) x s(-1)) in October. The soil respiration rates of the four vegetation communities had significant exponential correlations with ambient air temperature and soil temperature. Soil moisture, however, only played an important role in affecting the soil respiration rate of C. virgata community while air humidity near the soil surface was significantly correlated with the soil respiration rates of P. australis and L. chinensis communities. The soil salt contents seriously constrained the CO2 dioxide emission, and the soil pH, electrical conductivity (EC), exchangeable sodium percentage (ESP) could explain 87%-91% spatial variations of the soil respiration rate.

  4. Higher dropout rate in non-native patients than in native patients in rehabilitation in The Netherlands

    NARCIS (Netherlands)

    Sloots, Maurits; Scheppers, Emmanuel F.; van de Weg, Frans B.; Bartels, Edien A.; Geertzen, Jan H.; Dekker, Joost; Dekker, Jaap

    Dropout from a rehabilitation programme often occurs in patients with chronic nonspecific low back pain of non-native origin. However, the exact dropout rate is not known. The objective of this study was to determine the difference in dropout rate between native and non-native patients with chronic

  5. Accounting for Risk of Non-Completion in Private and Social Rates of Return to Higher Education

    Science.gov (United States)

    Toutkoushian, Robert K.; Shafiq, M. Najeeb; Trivette, Michael J.

    2013-01-01

    Conventional studies of the private and social rates of return to a Bachelor's degree focus on the earnings difference between Bachelor degree holders and high school graduates, and find that there are large rates of return for degree recipients. The estimates in these studies, however, do not take into account the risk of not completing a degree.…

  6. Trauma centers with higher rates of angiography have a lesser incidence of splenectomy in the management of blunt splenic injury.

    Science.gov (United States)

    Capecci, Louis M; Jeremitsky, Elan; Smith, R Stephen; Philp, Frances

    2015-10-01

    Nonoperative management (NOM) for blunt splenic injury (BSI) is well-established. Angiography (ANGIO) has been shown to improve success rates with NOM. Protocols for NOM are not standardized and vary widely between centers. We hypothesized that trauma centers that performed ANGIO at a greater rate would demonstrate decreased rates of splenectomy compared with trauma centers that used ANGIO less frequently. A large, multicenter, statewide database (Pennsylvania Trauma Systems Foundation) from 2007 to 2011 was used to generate the study cohort of patients with BSI (age ≥ 13). The cohort was divided into 2 populations based on admission to centers with high (≥13%) or low (Splenectomy rates were then compared between the 2 groups, and multivariable logistic regression for predictors of splenectomy (failed NOM) were also performed. The overall rate of splenectomy in the entire cohort was 21.0% (1,120 of 5,333 BSI patients). The high ANGIO group had a lesser rate of splenectoy compared with the low ANGIO group (19% vs 24%; P splenectomy compared with low ANGIO centers (odds ratio, 0.68; 95% CI 0.58-0.80; P splenectomy rates compared with centers with lesser rate of ANGIO. Inclusion of angiographic protocols for NOM of BSI should be considered strongly. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Effects of environmental factors and soil properties on topographic variations of soil respiration

    OpenAIRE

    Tamai, K.

    2010-01-01

    Soil respiration rates were measured along different parts of a slope in (a) an evergreen forest with common brown forest soil and (b) a deciduous forest with immature soil. The effects of soil temperature, soil moisture and soil properties were estimated individually, and the magnitudes of these effects in the deciduous and evergreen forests were compared. In the evergreen forest with common brown forest soil, soil properties had the greatest effect on soil respiration rates, followed by soi...

  8. Endothelial cell respiration is affected by the oxygen tension during shear exposure: role of mitochondrial peroxynitrite.

    Science.gov (United States)

    Jones, Charles I; Han, Zhaosheng; Presley, Tennille; Varadharaj, Saradhadevi; Zweier, Jay L; Ilangovan, Govindasamy; Alevriadou, B Rita

    2008-07-01

    Cultured vascular endothelial cell (EC) exposure to steady laminar shear stress results in peroxynitrite (ONOO(-)) formation intramitochondrially and inactivation of the electron transport chain. We examined whether the "hyperoxic state" of 21% O(2), compared with more physiological O(2) tensions (Po(2)), increases the shear-induced nitric oxide (NO) synthesis and mitochondrial superoxide (O(2)(*-)) generation leading to ONOO(-) formation and suppression of respiration. Electron paramagnetic resonance oximetry was used to measure O(2) consumption rates of bovine aortic ECs sheared (10 dyn/cm(2), 30 min) at 5%, 10%, or 21% O(2) or left static at 5% or 21% O(2). Respiration was inhibited to a greater extent when ECs were sheared at 21% O(2) than at lower Po(2) or left static at different Po(2). Flow in the presence of an endothelial NO synthase (eNOS) inhibitor or a ONOO(-) scavenger abolished the inhibitory effect. EC transfection with an adenovirus that expresses manganese superoxide dismutase in mitochondria, and not a control virus, blocked the inhibitory effect. Intracellular and mitochondrial O(2)(*-) production was higher in ECs sheared at 21% than at 5% O(2), as determined by dihydroethidium and MitoSOX red fluorescence, respectively, and the latter was, at least in part, NO-dependent. Accumulation of NO metabolites in media of ECs sheared at 21% O(2) was modestly increased compared with ECs sheared at lower Po(2), suggesting that eNOS activity may be higher at 21% O(2). Hence, the hyperoxia of in vitro EC flow studies, via increased NO and mitochondrial O(2)(*-) production, leads to enhanced ONOO(-) formation intramitochondrially and suppression of respiration.

  9. Quantitative change of EEG and respiration signals during mindfulness meditation

    Science.gov (United States)

    2014-01-01

    Background This study investigates measures of mindfulness meditation (MM) as a mental practice, in which a resting but alert state of mind is maintained. A population of older people with high stress level participated in this study, while electroencephalographic (EEG) and respiration signals were recorded during a MM intervention. The physiological signals during meditation and control conditions were analyzed with signal processing. Methods EEG and respiration data were collected and analyzed on 34 novice meditators after a 6-week meditation intervention. Collected data were analyzed with spectral analysis, phase analysis and classification to evaluate an objective marker for meditation. Results Different frequency bands showed differences in meditation and control conditions. Furthermore, we established a classifier using EEG and respiration signals with a higher accuracy (85%) at discriminating between meditation and control conditions than a classifier using the EEG signal only (78%). Conclusion Support vector machine (SVM) classifier with EEG and respiration feature vector is a viable objective marker for meditation ability. This classifier should be able to quantify different levels of meditation depth and meditation experience in future studies. PMID:24939519

  10. [Effects of Warming and Straw Application on Soil Respiration and Enzyme Activity in a Winter Wheat Cropland].

    Science.gov (United States)

    Chen, Shu-tao; Sang, Lin; Zhang, Xu; Hu, Zheng-hua

    2016-02-15

    In order to investigate the effects of warming and straw application on soil respiration and enzyme activity, a field experiment was performed from November 2014 to May 2015. Four treatments, which were control (CK), warming, straw application, and warming and straw application, were arranged in field. Seasonal variability in soil respiration, soil temperature and soil moisture for different treatments were measured. Urease, invertase, and catalase activities for different treatments were measured at the elongation, booting, and anthesis stages. The results showed that soil respiration in different treatments had similar seasonal variation patterns. Seasonal mean soil respiration rates for the CK, warming, straw application, and warming and straw application treatments were 1.46, 1.96, 1.92, and 2.45 micromol x (m2 x s)(-1), respectively. ANOVA indicated that both warming and straw applications significantly (P soil respiration compared to the control treatment. The relationship between soil respiration and soil temperature in different treatments fitted with the exponential regression function. The exponential regression functions explained 34.3%, 28.1%, 24.6%, and 32.0% variations of soil respiration for CK, warming, straw application, and warming and straw application treatments, respectively. Warming and straw applications significantly (P soil respiration and urease activity fitted with a linear regression function, with the P value of 0.061. The relationship between soil respiration and invertase (P = 0.013), and between soil respiration and catalase activity (P = 0.002) fitted well with linear regression functions.

  11. Higher Precision of Heart Rate Compared with VO2 to Predict Exercise Intensity in Endurance-Trained Runners.

    Science.gov (United States)

    Reis, Victor M; den Tillaar, Roland Van; Marques, Mario C

    2011-01-01

    The aim of the present study was to assess the precision of oxygen uptake with heart rate regression during track running in highly-trained runners. Twelve national and international level male long-distance road runners (age 30.7 ± 5.5 yrs, height 1.71 ± 0.04 m and mass 61.2 ± 5.8 kg) with a personal best on the half marathon of 62 min 37 s ± 1 min 22 s participated in the study. Each participant performed, in an all-weather synthetic track five, six min bouts at constant velocity with each bout at an increased running velocity. The starting velocity was 3.33 m·s(-1) with a 0.56 m·s(-1) increase on each subsequent bout. VO2 and heart rate were measured during the runs and blood lactate was assessed immediately after each run. Mean peak VO2 and mean peak heart rate were, respectively, 76.2 ± 9.7 mL·kg(-1)·min(-1) and 181 ± 13 beats·min(-1). The linearity of the regressions between heart rate, running velocity and VO2 were all very high (r > 0.99) with small standard errors of regression (i.e. Sy.x at the velocity associated with the 2 and 4 mmol·L(-1) lactate thresholds). The strong relationships between heart rate, running velocity and VO2 found in this study show that, in highly trained runners, it is possible to have heart rate as an accurate indicator of energy demand and of the running speed. Therefore, in this subject cohort it may be unnecessary to use VO2 to track changes in the subjects' running economy during training periods. Key pointsHeart rate is used in the control of exercise intensity in endurance sports.However, few studies have quantified the precision of its relationship with oxygen uptake in highly trained runners.We evaluated twelve elite half-marathon runners during track running at various intensities and established three regressions: oxygen uptake / heart rate; heart rate / running velocity and oxygen uptake / running velocity.The three regressions presented, respectively, imprecision of 4,2%, 2,75% and 4,5% at the velocity

  12. Experimental warming does not enhance soil respiration in a semiarid temperate forest-steppe ecosystem

    DEFF Research Database (Denmark)

    Lellei-Kovacs, E.; Kovacs-Lang, E.; Kalapos, T.

    2008-01-01

    are still limited. Soil respiration rate-measured monthly between April and November from 2003 to 2006-remained very low (0.09 - 1.53 mu mol CO2 m(-2) s(-1))in accordance with the moderate biological activity and low humus content of the nutrient poor, coarse sandy soil. Specific soil respiration rate...... ( calculated for unit soil organic matter content), however, was relatively high (0.36 - 7.92 mu mol CO g(-1) C(org)h(-1)) suggesting substrate limitation for soil biological activity. During the day, soil respiration rate was significantly lower at dawn than at midday, while seasonally clear temperature......The influence of simulated climate change on soil respiration was studied in a field experiment on 4 m x 5 m plots in the semiarid temperate Pannonian sand forest-steppe. This ecosystem type has low productivity and soil organic matter content, and covers large areas, yet data on soil carbon fluxes...

  13. Glucose, Lactate and Glutamine but not Glutamate Support Depolarization-Induced Increased Respiration in Isolated Nerve Terminals

    DEFF Research Database (Denmark)

    Hohnholt, Michaela C; Andersen, Vibe H; Bak, Lasse K

    2017-01-01

    Synaptosomes prepared from various aged and gene modified experimental animals constitute a valuable model system to study pre-synaptic mechanisms. Synaptosomes were isolated from whole brain and the XFe96 extracellular flux analyzer (Seahorse Bioscience) was used to study mitochondrial respiration...... and antimycin A. The synaptosomes exhibited intense respiratory activity using glucose as substrate. The FCCP-dependent respiration was significantly higher with 10 mM glucose compared to 1 mM glucose. Synaptosomes also readily used pyruvate as substrate, which elevated basal respiration, activity......-dependent respiration induced by veratridine and the respiratory response to uncoupling compared to that obtained with glucose as substrate. Also lactate was used as substrate by synaptosomes but in contrast to pyruvate, mitochondrial lactate mediated respiration was comparable to respiration using glucose as substrate...

  14. Soil respiration in the cold desert environment of the Colorado Plateau (USA): Abiotic regulators and thresholds

    Science.gov (United States)

    Fernandez, D.P.; Neff, J.C.; Belnap, J.; Reynolds, R.L.

    2006-01-01

    Decomposition is central to understanding ecosystem carbon exchange and nutrient-release processes. Unlike mesic ecosystems, which have been extensively studied, xeric landscapes have received little attention; as a result, abiotic soil-respiration regulatory processes are poorly understood in xeric environments. To provide a more complete and quantitative understanding about how abiotic factors influence soil respiration in xeric ecosystems, we conducted soil- respiration and decomposition-cloth measurements in the cold desert of southeast Utah. Our study evaluated when and to what extent soil texture, moisture, temperature, organic carbon, and nitrogen influence soil respiration and examined whether the inverse-texture hypothesis applies to decomposition. Within our study site, the effect of texture on moisture, as described by the inverse texture hypothesis, was evident, but its effect on decomposition was not. Our results show temperature and moisture to be the dominant abiotic controls of soil respiration. Specifically, temporal offsets in temperature and moisture conditions appear to have a strong control on soil respiration, with the highest fluxes occurring in spring when temperature and moisture were favorable. These temporal offsets resulted in decomposition rates that were controlled by soil moisture and temperature thresholds. The highest fluxes of CO2 occurred when soil temperature was between 10 and 16??C and volumetric soil moisture was greater than 10%. Decomposition-cloth results, which integrate decomposition processes across several months, support the soil-respiration results and further illustrate the seasonal patterns of high respiration rates during spring and low rates during summer and fall. Results from this study suggest that the parameters used to predict soil respiration in mesic ecosystems likely do not apply in cold-desert environments. ?? Springer 2006.

  15. Are Cancer incidence Rates Among Present And Past Workers Of The research Centers Of The Atomic Energy Commission higher Than The Rates Among The General Population?

    International Nuclear Information System (INIS)

    Litai, D.

    1999-01-01

    Cancer incidence rates among the workers of the AEC and its retirees have increased several fold in the last decade compared to the rates experienced in previous ones. This has brought about a wave of claims for compensation with negative repercussions in the media about the state of radiation safety in the nuclear research centers in the country. The Nuclear Research Center - Negev, being, generally closed to public and media visits, has taken the brunt of this criticism. Consequently, the question spelled out in the title has caused much concern and deserves to be discussed and explained. The purpose of this paper is to review what we know in this context and to show that the observed morbidity rates, worrying as they may be, are entirely natural, and, by and large, unrelated to the occupational exposures of the workers. It is well known that cancer incidence rates in the population rise steeply with age, especially over 50. As both research centers are approaching the age of 40, it is clear that a very large fraction of the workers and all retirees have passed this age and many are already in their sixties and even seventies. It is a well established fact that close to 40% of the population in this country (and many others as well) develop some type of cancer during their lifetime and close to a half of these succumb to it. As most of those cancers occur after the age of 50, this explains the increased rates alluded to above. Notably, numerous research centers around the globe have reached similar ages in the last decade and experience similar increases in morbidity, that have caused understandable concern and the initiation of epidemiological studies intended to identify the health effects of extended exposures to low doses, if any. Such studies have been carried out in several countries and followed, altogether, about 100,000 workers through 40 years. The studies showed no excess of cancer mortality among workers compared to the general population (adjusted

  16. Significance of heme-based respiration in meat spoilage caused by Leuconostoc gasicomitatum.

    Science.gov (United States)

    Jääskeläinen, Elina; Johansson, Per; Kostiainen, Olli; Nieminen, Timo; Schmidt, Georg; Somervuo, Panu; Mohsina, Marzia; Vanninen, Paula; Auvinen, Petri; Björkroth, Johanna

    2013-02-01

    Leuconostoc gasicomitatum is a psychrotrophic lactic acid bacterium (LAB) which causes spoilage in cold-stored modified-atmosphere-packaged (MAP) meat products. In addition to the fermentative metabolism, L. gasicomitatum is able to respire when exogenous heme and oxygen are available. In this study, we investigated the respiration effects on growth rate, biomass, gene expression, and volatile organic compound (VOC) production in laboratory media and pork loin. The meat samples were evaluated by a sensory panel every second or third day for 29 days. We observed that functional respiration increased the growth (rate and yield) of L. gasicomitatum in laboratory media with added heme and in situ meat with endogenous heme. Respiration increased enormously (up to 2,600-fold) the accumulation of acetoin and diacetyl, which are buttery off-odor compounds in meat. Our transcriptome analyses showed that the gene expression patterns were quite similar, irrespective of whether respiration was turned off by excluding heme from the medium or mutating the cydB gene, which is essential in the respiratory chain. The respiration-based growth of L. gasicomitatum in meat was obtained in terms of population development and subsequent development of sensory characteristics. Respiration is thus a key factor explaining why L. gasicomitatum is so well adapted in high-oxygen packed meat.

  17. Acclimation and soil moisture constrain sugar maple root respiration in experimentally warmed soil.

    Science.gov (United States)

    Jarvi, Mickey P; Burton, Andrew J

    2013-09-01

    The response of root respiration to warmer soil can affect ecosystem carbon (C) allocation and the strength of positive feedbacks between climatic warming and soil CO2 efflux. This study sought to determine whether fine-root (maple (Acer saccharum Marsh.)-dominated northern hardwood forest would adjust to experimentally warmed soil, reducing C return to the atmosphere at the ecosystem scale to levels lower than that would be expected using an exponential temperature response function. Infrared heating lamps were used to warm the soil (+4 to +5 °C) in a mature sugar maple forest in a fully factorial design, including water additions used to offset the effects of warming-induced dry soil. Fine-root-specific respiration rates, root biomass, root nitrogen (N) concentration, soil temperature and soil moisture were measured from 2009 to 2011, with experimental treatments conducted from late 2010 to 2011. Partial acclimation of fine-root respiration to soil warming occurred, with soil moisture deficit further constraining specific respiration rates in heated plots. Fine-root biomass and N concentration remained unchanged. Over the 2011 growing season, ecosystem root respiration was not significantly greater in warmed soil. This result would not be predicted by models that allow respiration to increase exponentially with temperature and do not directly reduce root respiration in drier soil.

  18. Mitochondrial Respiration Is Reduced in Atherosclerosis, Promoting Necrotic Core Formation and Reducing Relative Fibrous Cap Thickness.

    Science.gov (United States)

    Yu, Emma P K; Reinhold, Johannes; Yu, Haixiang; Starks, Lakshi; Uryga, Anna K; Foote, Kirsty; Finigan, Alison; Figg, Nichola; Pung, Yuh-Fen; Logan, Angela; Murphy, Michael P; Bennett, Martin

    2017-12-01

    Mitochondrial DNA (mtDNA) damage is present in murine and human atherosclerotic plaques. However, whether endogenous levels of mtDNA damage are sufficient to cause mitochondrial dysfunction and whether decreasing mtDNA damage and improving mitochondrial respiration affects plaque burden or composition are unclear. We examined mitochondrial respiration in human atherosclerotic plaques and whether augmenting mitochondrial respiration affects atherogenesis. Human atherosclerotic plaques showed marked mitochondrial dysfunction, manifested as reduced mtDNA copy number and oxygen consumption rate in fibrous cap and core regions. Vascular smooth muscle cells derived from plaques showed impaired mitochondrial respiration, reduced complex I expression, and increased mitophagy, which was induced by oxidized low-density lipoprotein. Apolipoprotein E-deficient (ApoE -/- ) mice showed decreased mtDNA integrity and mitochondrial respiration, associated with increased mitochondrial reactive oxygen species. To determine whether alleviating mtDNA damage and increasing mitochondrial respiration affects atherogenesis, we studied ApoE -/- mice overexpressing the mitochondrial helicase Twinkle (Tw + /ApoE -/- ). Tw + /ApoE -/- mice showed increased mtDNA integrity, copy number, respiratory complex abundance, and respiration. Tw + /ApoE -/- mice had decreased necrotic core and increased fibrous cap areas, and Tw + /ApoE -/- bone marrow transplantation also reduced core areas. Twinkle increased vascular smooth muscle cell mtDNA integrity and respiration. Twinkle also promoted vascular smooth muscle cell proliferation and protected both vascular smooth muscle cells and macrophages from oxidative stress-induced apoptosis. Endogenous mtDNA damage in mouse and human atherosclerosis is associated with significantly reduced mitochondrial respiration. Reducing mtDNA damage and increasing mitochondrial respiration decrease necrotic core and increase fibrous cap areas independently of changes in

  19. Boreal and temperate trees show strong acclimation of respiration to warming.

    Science.gov (United States)

    Reich, Peter B; Sendall, Kerrie M; Stefanski, Artur; Wei, Xiaorong; Rich, Roy L; Montgomery, Rebecca A

    2016-03-31

    Plant respiration results in an annual flux of carbon dioxide (CO2) to the atmosphere that is six times as large as that due to the emissions from fossil fuel burning, so changes in either will impact future climate. As plant respiration responds positively to temperature, a warming world may result in additional respiratory CO2 release, and hence further atmospheric warming. Plant respiration can acclimate to altered temperatures, however, weakening the positive feedback of plant respiration to rising global air temperature, but a lack of evidence on long-term (weeks to years) acclimation to climate warming in field settings currently hinders realistic predictions of respiratory release of CO2 under future climatic conditions. Here we demonstrate strong acclimation of leaf respiration to both experimental warming and seasonal temperature variation for juveniles of ten North American tree species growing for several years in forest conditions. Plants grown and measured at 3.4 °C above ambient temperature increased leaf respiration by an average of 5% compared to plants grown and measured at ambient temperature; without acclimation, these increases would have been 23%. Thus, acclimation eliminated 80% of the expected increase in leaf respiration of non-acclimated plants. Acclimation of leaf respiration per degree temperature change was similar for experimental warming and seasonal temperature variation. Moreover, the observed increase in leaf respiration per degree increase in temperature was less than half as large as the average reported for previous studies, which were conducted largely over shorter time scales in laboratory settings. If such dampening effects of leaf thermal acclimation occur generally, the increase in respiration rates of terrestrial plants in response to climate warming may be less than predicted, and thus may not raise atmospheric CO2 concentrations as much as anticipated.

  20. Faster eating rates are associated with higher energy intakes during an ad libitum meal, higher BMI and greater adiposity among 4·5-year-old children: results from the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) cohort.

    Science.gov (United States)

    Fogel, Anna; Goh, Ai Ting; Fries, Lisa R; Sadananthan, Suresh A; Velan, S Sendhil; Michael, Navin; Tint, Mya-Thway; Fortier, Marielle V; Chan, Mei Jun; Toh, Jia Ying; Chong, Yap-Seng; Tan, Kok Hian; Yap, Fabian; Shek, Lynette P; Meaney, Michael J; Broekman, Birit F P; Lee, Yung Seng; Godfrey, Keith M; Chong, Mary F F; Forde, Ciarán G

    2017-04-01

    Faster eating rates are associated with increased energy intake, but little is known about the relationship between children's eating rate, food intake and adiposity. We examined whether children who eat faster consume more energy and whether this is associated with higher weight status and adiposity. We hypothesised that eating rate mediates the relationship between child weight and ad libitum energy intake. Children (n 386) from the Growing Up in Singapore Towards Healthy Outcomes cohort participated in a video-recorded ad libitum lunch at 4·5 years to measure acute energy intake. Videos were coded for three eating-behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min). BMI and anthropometric indices of adiposity were measured. A subset of children underwent MRI scanning (n 153) to measure abdominal subcutaneous and visceral adiposity. Children above/below the median eating rate were categorised as slower and faster eaters, and compared across body composition measures. There was a strong positive relationship between eating rate and energy intake (r 0·61, P<0·001) and a positive linear relationship between eating rate and children's BMI status. Faster eaters consumed 75 % more energy content than slower eating children (Δ548 kJ (Δ131 kcal); 95 % CI 107·6, 154·4, P<0·001), and had higher whole-body (P<0·05) and subcutaneous abdominal adiposity (Δ118·3 cc; 95 % CI 24·0, 212·7, P=0·014). Mediation analysis showed that eating rate mediates the link between child weight and energy intake during a meal (b 13·59; 95 % CI 7·48, 21·83). Children who ate faster had higher energy intake, and this was associated with increased BMI z-score and adiposity.

  1. HIGHER PRECISION OF HEART RATE COMPARED WITH VO2 TO PREDICT EXERCISE INTENSITY IN ENDURANCE-TRAINED RUNNERS

    Directory of Open Access Journals (Sweden)

    Victor M. Reis

    2011-03-01

    Full Text Available The aim of the present study was to assess the precision of oxygen uptake with heart rate regression during track running in highly-trained runners. Twelve national and international level male long-distance road runners (age 30.7 ± 5.5 yrs, height 1.71 ± 0.04 m and mass 61.2 ± 5.8 kg with a personal best on the half marathon of 62 min 37 s ± 1 min 22 s participated in the study. Each participant performed, in an all-weather synthetic track five, six min bouts at constant velocity with each bout at an increased running velocity. The starting velocity was 3.33 m·s-1 with a 0.56 m·s-1 increase on each subsequent bout. VO2 and heart rate were measured during the runs and blood lactate was assessed immediately after each run. Mean peak VO2 and mean peak heart rate were, respectively, 76.2 ± 9.7 mL·kg-1·min-1 and 181 ± 13 beats·min-1. The linearity of the regressions between heart rate, running velocity and VO2 were all very high (r > 0.99 with small standard errors of regression (i.e. Sy.x < 5% at the velocity associated with the 2 and 4 mmol·L-1 lactate thresholds. The strong relationships between heart rate, running velocity and VO2 found in this study show that, in highly trained runners, it is possible to have heart rate as an accurate indicator of energy demand and of the running speed. Therefore, in this subject cohort it may be unnecessary to use VO2 to track changes in the subjects' running economy during training periods.

  2. Mitochondrial respiration is sensitive to cytoarchitectural breakdown.

    Science.gov (United States)

    Kandel, Judith; Angelin, Alessia A; Wallace, Douglas C; Eckmann, David M

    2016-11-07

    An abundance of research suggests that cellular mitochondrial and cytoskeletal disruption are related, but few studies have directly investigated causative connections between the two. We previously demonstrated that inhibiting microtubule and microfilament polymerization affects mitochondrial motility on the whole-cell level in fibroblasts. Since mitochondrial motility can be indicative of mitochondrial function, we now further characterize the effects of these cytoskeletal inhibitors on mitochondrial potential, morphology and respiration. We found that although they did not reduce mitochondrial inner membrane potential, cytoskeletal toxins induced significant decreases in basal mitochondrial respiration. In some cases, basal respiration was only affected after cells were pretreated with the calcium ionophore A23187 in order to stress mitochondrial function. In most cases, mitochondrial morphology remained unaffected, but extreme microfilament depolymerization or combined intermediate doses of microtubule and microfilament toxins resulted in decreased mitochondrial lengths. Interestingly, these two particular exposures did not affect mitochondrial respiration in cells not sensitized with A23187, indicating an interplay between mitochondrial morphology and respiration. In all cases, inducing maximal respiration diminished differences between control and experimental groups, suggesting that reduced basal respiration originates as a largely elective rather than pathological symptom of cytoskeletal impairment. However, viability experiments suggest that even this type of respiration decrease may be associated with cell death.

  3. Elemental Concentration of Inhalable and Respirable Particulate ...

    African Journals Online (AJOL)

    20537 and respirable foam for I.O.M sampler. The elemental composition (Co, Ni, Zn, Cu, Fe, Pb, Cr, Mn and Cd) were analyzed by using Atomic Absorption Spectrophotometric (AAS). The data generated were subjected to descriptive analysis. In inhalable fraction,the enrichment factor ranged from 1-73.3 while in respirable ...

  4. Respirators: APR Issuer Self Study 33461

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Laboratory

    2016-07-13

    Respirators: APR Issuer Self-Study (course 33461) is designed to introduce and familiarize employees selected as air-purifying respirator (APR) issuers at Los Alamos National Laboratory (LANL) with the responsibilities, limitations, procedures, and resources for issuing APRs at LANL. The goal is to enable these issuers to consistently provide proper, functioning APRs to authorized users

  5. The Effect of Restoration on Soil Respiration in an Urban Tidal Wetland in the Meadowlands, New Jersey

    Science.gov (United States)

    Schafer, K. V.; Kurepa, S.; Duman, T.; Scott, M.; Pechmann, I.; Vanderklein, D. W.

    2017-12-01

    The effect of wetland restoration on soil respiration in tidal brackish marshes has not been comprehensively studied. In New Jersey, common mitigation efforts come in the form of the removal of an invasive haplotype of Phragmites australis and replanting of native species, resulting in significant habitat disturbance. This study investigated the differences in soil respiration within and between areas covered with P. australis, Spartina alterniflora, and Spartina patens. We performed static chamber measurements of soil respiration using an infrared gas analyzer to measure CO2 fluxes in a natural site and a mitigated site in the Meadowlands of New Jersey. Daytime measurements were performed in 10 random locations in areas populated with each of the vegetation types, to represent the spatial heterogeneity of the wetland area, during summer 2017. Due to the nature of the wetland, vegetation had to be removed to uncover the soil. Prior to measuring exposed soil respiration, we therefore measured CO2 flux including the vegetation within the chamber, which allowed us to additionally calculate the respiration including the vegetation. Furthermore, we assessed direct respiration of green leaves with leaf gas exchange measurements. Combining these different methodologies and scales allow us to estimate the function of different components that contribute to total respiration from the wetland, and how they change spatially and temporally. Initial results showed that soil respiration in P. australis patches was much higher than in both Spartina species, however average vegetation respiration per unit mass was similar across all three. Vegetation respiration and soil respiration are of the same order of magnitude in all three species as well. Also, when respiration with and without vegetation was combined, P. australis showed a considerably higher flux.

  6. Heterotrophic components of soil respiration in pastures and forests in southwestern Amazonia, Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Eric Atlas Davidson

    2008-12-01

    Full Text Available In this paper we present data on soil microbial biomass and heterotrophic respiration in pastures, mature and secondary forests, in order to elucidate their contribution to total CO2 flux from soil to atmosphere. The research was conducted in Southwestern Amazonia, Acre State, Brazil. Microbial biomass was estimated using a variation of the traditional fumigation-extraction method and heterotrophic respiration was measured using respirometry flasks attached to an infrared gas analyzer. Soil microbial biomass and heterotrophic respiration did not differ statistically among pastures, mature and secondary forests. These laboratory results indicate that higher CO2 fluxes from pasture soils measured in situ are probably due to higher root respiration by pasture grasses.

  7. Contributions of ectomycorrhizal fungal mats to forest soil respiration

    Science.gov (United States)

    C. Phillips; L.A. Kluber; J.P. Martin; B.A. Caldwell; B.J. Bond

    2012-01-01

    Distinct aggregations of fungal hyphae and rhizomorphs, or “mats”, formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon to investigate whether there was...

  8. Oxygen dependence of respiration in rat spinotrapezius muscle in situ

    OpenAIRE

    Golub, Aleksander S.; Pittman, Roland N.

    2012-01-01

    The oxygen dependence of respiration in striated muscle in situ was studied by measuring the rate of decrease of interstitial Po2 [oxygen disappearance curve (ODC)] following rapid arrest of blood flow by pneumatic tissue compression, which ejected red blood cells from the muscle vessels and made the ODC independent from oxygen bound to hemoglobin. After the contribution of photo-consumption of oxygen by the method was evaluated and accounted for, the corrected ODCs were converted into the Po...

  9. Influence of vestibular activation on respiration in humans

    Science.gov (United States)

    Monahan, Kevin D.; Sharpe, Melissa K.; Drury, Daniel; Ertl, Andrew C.; Ray, Chester A.

    2002-01-01

    The purpose of this study was to determine the effects of the semicircular canals and otolith organs on respiration in humans. On the basis of animal studies, we hypothesized that vestibular activation would elicit a vestibulorespiratory reflex. To test this hypothesis, respiratory measures, arterial blood pressure, and heart rate were measured during engagement of semicircular canals and/or otolith organs. Dynamic upright pitch and roll (15 cycles/min), which activate the otolith organs and semicircular canals, increased respiratory rate (Delta2 +/- 1 and Delta3 +/- 1 breaths/min, respectively; P < 0.05). Dynamic yaw and lateral pitch (15 cycles/min), which activate the semicircular canals, increased respiration similarly (Delta3 +/- 1 and Delta2 +/- 1, respectively; P < 0.05). Dynamic chair rotation (15 cycles/min), which mimics dynamic yaw but eliminates neck muscle afferent, increased respiration (Delta3 +/- 1; P < 0.05) comparable to dynamic yaw (15 cycles/min). Increases in respiratory rate were graded as greater responses occurred during upright (Delta5 +/- 2 breaths/min) and lateral pitch (Delta4 +/- 1) and roll (Delta5 +/- 1) performed at 30 cycles/min. Increases in breathing frequency resulted in increases in minute ventilation during most interventions. Static head-down rotation, which activates otolith organs, did not alter respiratory rate (Delta1 +/- 1 breaths/min). Collectively, these data indicate that semicircular canals, but not otolith organs or neck muscle afferents, mediate increased ventilation in humans and support the concept that vestibular activation alters respiration in humans.

  10. Score of Inattention Subscale of ADHD Rating Scale-IV is Significantly Higher for AD/HD than PDD.

    OpenAIRE

    Fujibayashi, Hiromi; Kitayama, Shinji; Matsuo, Masafumi

    2010-01-01

    Attention-deficit/hyperactivity disorder (AD/HD) and pervasive developmental disorder (PDD) must be differentiated because the respective treatments are different. However, they are difficult to distinguish because they often show similar symptoms. At our hospital, we have the rearer of a patient answer both the ADHD Rating Scale-IV (ADHD-RS) and the Autism Spectrum Screening Questionnaire (ASSQ), and use the results as an aid for the diagnosis of AD/HD or PDD. These results were compared wit...

  11. Hydraulic conductance as well as nitrogen accumulation plays a role in the higher rate of leaf photosynthesis of the most productive variety of rice in Japan.

    Science.gov (United States)

    Taylaran, Renante D; Adachi, Shunsuke; Ookawa, Taiichiro; Usuda, Hideaki; Hirasawa, Tadashi

    2011-07-01

    An indica variety Takanari is known as one of the most productive rice varieties in Japan and consistently produces 20-30% heavier dry matter during ripening than Japanese commercial varieties in the field. The higher rate of photosynthesis of individual leaves during ripening has been recognized in Takanari. By using pot-grown plants under conditions of minimal mutual shading, it was confirmed that the higher rate of leaf photosynthesis is responsible for the higher dry matter production after heading in Takanari as compared with a japonica variety, Koshihikari. The rate of leaf photosynthesis and shoot dry weight became larger in Takanari after the panicle formation and heading stages, respectively, than in Koshihikari. Roots grew rapidly in the panicle formation stage until heading in Takanari compared with Koshihikari. The higher rate of leaf photosynthesis in Takanari resulted not only from the higher content of leaf nitrogen, which was caused by its elevated capacity for nitrogen accumulation, but also from higher stomatal conductance. When measured under light-saturated conditions, stomatal conductance was already decreased due to the reduction in leaf water potential in Koshihikari even under conditions of a relatively small difference in leaf-air vapour pressure difference. In contrast, the higher stomatal conductance was supported by the maintenance of higher leaf water potential through the higher hydraulic conductance in Takanari with the larger area of root surface. However, no increase in root hydraulic conductivity was expected in Takanari. The larger root surface area of Takanari might be a target trait in future rice breeding for increasing dry matter production.

  12. Association between higher levels of sexual function, activity, and satisfaction and self-rated successful aging in older postmenopausal women

    Science.gov (United States)

    Thompson, Wesley K.; Charo, Lindsey; Vahia, Ipsit V.; Depp, Colin; Allison, Matthew; Jeste, Dilip V.

    2014-01-01

    Objectives To determine if measures of successful-aging are associated with sexual activity, satisfaction, and function in older post-menopausal women. Design Cross-sectional study using self-report surveys; analyses include chi-square and t-tests and multiple linear regression analyses. Setting Community-dwelling older post-menopausal women in the greater San Diego Region. Participants 1,235 community-dwelling women aged 60-89 years participating at the San Diego site of the Women's Health Initiative. Measurements Demographics and self-report measures of sexual activity, function, and satisfaction and successful aging. Results Sexual activity and functioning (desire, arousal, vaginal tightness, use of lubricants, and ability to climax) were negatively associated with age, as were physical and mental health. In contrast, sexual satisfaction and self-rated successful aging and quality of life remained unchanged across age groups. Successful aging measures were positively associated with sexual measures, especially self-rated quality of life and sexual satisfaction. Conclusions Self-rated successful aging, quality of life, and sexual satisfaction appear to be stable in the face of declines in physical health, some cognitive abilities, and sexual activity and function and are positively associated with each other across ages 60-89 years. PMID:21797827

  13. INFLUENCE OF SILVOPASTORAL SYSTEM “LIVE FENCES” OF Gliricidia sepium ON SOIL RESPIRATION IN TACOTALPA, TABASCO, MEXICO

    Directory of Open Access Journals (Sweden)

    G. Villanueva-López

    2014-08-01

    Full Text Available The aim of this study was to quantify rates of soil respiration on livestock systems with live fences (LF formed by Gliricidia sepium trees and on livestock systems in signal grass monoculture (MP (Brachiaria decumbens; examine the variation of flows in the rainy and dry seasons, and fluctuations during the day, as well as soil temperature and relative humidity. Soil respiration was measured twice a month, four times a day between the hours of 00:00 to 06:00 h, 6:00 to 12:00 h, 12:00 to 18:00 h, and 18:00 to 24:00 h, in both seasons. Soil temperature and the relative humidity were simultaneously measured. The results show that the rate of soil respiration is similar between these systems, LF issued 0.97 and MP 1.01 mol CO2 m2 h-1. In contrast, there was influence of the time of year and time of collection of the samples. In both systems the soil flows were higher in the rainy season (1.1 mol CO2 m2 h-1 on average and slightly lower in the dry season (0.90 mol CO2 m2 h-1 on average and were higher during the night (00:00 to 06:00 hours, during the early morning hours (6:00 to 12:00 hours. Soil temperature was higher in the MP, and the relative humidity in LF. It is concluded that the main factor that caused the variation in soil respiration rates was the presence of G. sepium trees in LF, which led to lower temperatures and more stable humidity, which resulted in lower soil CO2 fluxes.

  14. Direct Effects of (−-Epicatechin and Procyanidin B2 on the Respiration of Rat Heart Mitochondria

    Directory of Open Access Journals (Sweden)

    Dalia M. Kopustinskiene

    2015-01-01

    Full Text Available Flavonol (−-epicatechin and its derived dimer procyanidin B2, present in high amounts in cocoa products, have been shown to exert beneficial effects on the heart and cardiovascular system; however, their mechanism of action has not been fully elucidated. We studied effects of (−-epicatechin and procyanidin B2 on the oxidative phosphorylation of isolated rat heart mitochondria. (−-Epicatechin and procyanidin B2 had stimulating effect (up to 30% compared to control on substrate-driven (State 2 mitochondrial respiration. Their effect was dependent on the respiratory substrates used. (−-Epicatechin at higher concentrations (from 0.27 µg/mL significantly decreased (up to 15% substrate- and ADP-driven (State 3 mitochondrial respiration in case of pyruvate and malate oxidation only. Procyanidin B2 (0.7–17.9 ng/mL inhibited State 3 respiration rate up to 19%, the most profound effect being expressed with succinate as the substrate. (−-Epicatechin at concentrations of 0.23 µg/mL and 0.46 µg/mL prevented loss of the cytochrome c from mitochondria when substrate was succinate, supporting the evidence of membrane stabilizing properties of this flavonol. Thus, both (−-epicatechin and procyanidin B2 directly influenced mitochondrial functions and the observed effects could help to explain cardiometabolic risk reduction ascribed to the consumption of modest amounts of cocoa products.

  15. Arbuscular Mycorrhizal Symbiosis with Arundo donax Decreases Root Respiration and Increases Both Photosynthesis and Plant Biomass Accumulation.

    Science.gov (United States)

    Romero-Munar, Antònia; Del-Saz, Néstor Fernández; Ribas-Carbó, Miquel; Flexas, Jaume; Baraza, Elena; Florez-Sarasa, Igor; Fernie, Alisdair Robert; Gulías, Javier

    2017-07-01

    The effect of arbuscular mycorrhiza (AM) symbiosis on plant growth is associated with the balance between costs and benefits. A feedback regulation loop has been described in which the higher carbohydrate cost to plants for AM symbiosis is compensated by increases in their photosynthetic rates. Nevertheless, plant carbon balance depends both on photosynthetic carbon uptake and respiratory carbon consumption. The hypothesis behind this research was that the role of respiration in plant growth under AM symbiosis may be as important as that of photosynthesis. This hypothesis was tested in Arundo donax L. plantlets inoculated with Rhizophagus irregularis and Funneliformis mosseae. We tested the effects of AM inoculation on both photosynthetic capacity and in vivo leaf and root respiration. Additionally, analyses of the primary metabolism and ion content were performed in both leaves and roots. AM inoculation increased photosynthesis through increased CO 2 diffusion and electron transport in the chloroplast. Moreover, respiration decreased only in AM roots via the cytochrome oxidase pathway (COP) as measured by the oxygen isotope technique. This decline in the COP can be related to the reduced respiratory metabolism and substrates (sugars and tricarboxylic acid cycle intermediates) observed in roots. © 2017 John Wiley & Sons Ltd.

  16. Respiration and carbon dynamics of free-living and particle-attached bacteria in coastal waters of NE Pacific

    Science.gov (United States)

    Guo, C.; Ke, Y.; Liu, H.

    2016-02-01

    Bacterial respiration (BR) rates are fundamental to understand the role of bacteria in carbon flow in aquatic ecosystem, and therefore it is critical to obtain reliable measurements. Prefiltration- (mostly 1-3μm) and dark-incubation- (mostly 24 h) based direct measurements of oxygen consumption have been the most commonly used method for BR. However, the prefiltration procedure and long incubation time may cause change of the bacterial abundance and structure, leading to inaccurate measurements. In this study, by measuring bacterial abundance, production and respiration of both particle-attached (PA) and free-living (FL) bacteria at two contrasting site in coastal NE Pacific from Nov 2014 to Mar 2015, we found that the 24 h growth rate of FL bacteria in the traditional BR incubations were significantly higher for 30% and 54% than those obtained for FL and total (FL+PA) bacteria in unfiltered incubations respectively, suggesting removal of protist grazers could cause a significant biomass accumulation during 24 h incubation than the in situ condition. This biomass overestimation resulted in 40% (±12%) overestimation of measured FL BR rates compared with the corrected in situ FL BR. Nevertheless, for the corrected in situ total BR, the rates were overestimated by traditional method in three measurements over nine for 6-46%, and were underestimated in the rest six measurements for 7-67%. Interestingly, those underestimations were attributed to the ignorance of PA bacteria due to prefiltration, which had larger cell size than the FL bacteria, accounted for 19% (±16%) in total bacterial abundance, and contributed to 50% (±19%) of total bacterial production. The average bacterial growth efficiency calculated by comparable 24 h integrated bacterial production and respiration was 0.42 (±0.24). Our results confirmed two major flaws in the current BR methodology, i.e., 1) it only measures the respiration of FL bacteria, and 2) the removal of grazers causing dramatic

  17. Estimating respiration of roots in soil: interactions with soil CO2, soil temperature and soil water content

    NARCIS (Netherlands)

    Bouma, T.J.; Nielsen, K.F.; Eissenstat, D.M.; Lynch, J.P.

    1997-01-01

    Little information is available on the variability of the dynamics of the actual and observed root respiration rate in relation to abiotic factors. In this study, we describe I) interactions between soil CO2 concentration, temperature, soil water content and root respiration, and II) the effect of

  18. Respiration of midges (Diptera; Chironomidae) in British Columbian lakes: oxy-regulation, temperature and their role as palaeo-indicators

    DEFF Research Database (Denmark)

    Brodersen, Klaus Peter; Pedersen, Ole; Walker, Ian R.

    2008-01-01

    1. The specific respiration rate of 13 chironomid taxa and Chaoborus were measured to test the hypothesis of the relation between a species' ability to regulate their oxygen uptake and their distributional patterns among nine study lakes in British Columbia, Canada. 2. Respiration patterns of ind...

  19. Do More Hospital Beds Lead to Higher Hospitalization Rates? A Spatial Examination of Roemer’s Law

    Science.gov (United States)

    Delamater, Paul L.; Messina, Joseph P.; Grady, Sue C.; WinklerPrins, Vince; Shortridge, Ashton M.

    2013-01-01

    Background Roemer’s Law, a widely cited principle in health care policy, states that hospital beds that are built tend to be used. This simple but powerful expression has been invoked to justify Certificate of Need regulation of hospital beds in an effort to contain health care costs. Despite its influence, a surprisingly small body of empirical evidence supports its content. Furthermore, known geographic factors influencing health services use and the spatial structure of the relationship between hospital bed availability and hospitalization rates have not been sufficiently explored in past examinations of Roemer’s Law. We pose the question, “Accounting for space in health care access and use, is there an observable association between the availability of hospital beds and hospital utilization?” Methods We employ an ecological research design based upon the Anderson behavioral model of health care utilization. This conceptual model is implemented in an explicitly spatial context. The effect of hospital bed availability on the utilization of hospital services is evaluated, accounting for spatial structure and controlling for other known determinants of hospital utilization. The stability of this relationship is explored by testing across numerous geographic scales of analysis. The case study comprises an entire state system of hospitals and population, evaluating over one million inpatient admissions. Results We find compelling evidence that a positive, statistically significant relationship exists between hospital bed availability and inpatient hospitalization rates. Additionally, the observed relationship is invariant with changes in the geographic scale of analysis. Conclusions This study provides evidence for the effects of Roemer’s Law, thus suggesting that variations in hospitalization rates have origins in the availability of hospital beds. This relationship is found to be robust across geographic scales of analysis. These findings suggest

  20. Effects of inorganic mercury on the respiration and the swimming activity of shrimp larvae, Pandalus borealis

    Energy Technology Data Exchange (ETDEWEB)

    St-Amand, L.; Gagnon, R.; Packard, T.T.; Savenkoff, C. [Department of Fisheries and Oceans, Maurice Lamontagne Institute, Division of Ocean Sciences, 850 Rte de la Mer, P.O. Box 1000, Mont-Joli, Quebec G5H 3Z4 (Canada)

    1999-01-01

    In order to test the sensitivity of respiration (physiological and potential) to mercury (Hg) contamination, larval shrimp Pandalus borealis were exposed to inorganic Hg (0-160 ppb) for 27 h in the laboratory. Oxygen consumption rates (RO{sub 2}), potential respiration (determined by respiratory electron transfer system activity, ETSA), protein content, and swimming activity for zoeae III and zoeae V stages were measured. For both zoeae stages, ETSA and protein content remained constant after 27 h exposure to 160 ppb Hg whereas RO{sub 2} and swimming activity decreased. This study revealed the impact of different Hg levels and different exposure times on RO{sub 2} of shrimp larvae. After 10 h exposure to 160 ppb Hg, the RO{sub 2} decreased by 43 and 49% in zoeae III and zoeae V stages, respectively. Exposure time of 27 h to 80 ppb Hg and higher, induced paralysis in nearly 100% larvae. Surprisingly, the paralysed larvae displayed almost 50% of the control's RO{sub 2}. The results showed that Hg disturbs a part of the respiration process without modifying the maximum activity of the enzymes involved in the ETSA assay. Therefore, the ETSA assay can not be used as a sublethal bioanalytic probe to detect Hg in short-term exposures. The decline of the RO{sub 2}/ETSA ratios reported here, indicates an inability of contaminated larvae to adapt their metabolism to physiological stress caused by Hg. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Convergence in the temperature response of leaf respiration across biomes and plant functional types.

    Science.gov (United States)

    Heskel, Mary A; O'Sullivan, Odhran S; Reich, Peter B; Tjoelker, Mark G; Weerasinghe, Lasantha K; Penillard, Aurore; Egerton, John J G; Creek, Danielle; Bloomfield, Keith J; Xiang, Jen; Sinca, Felipe; Stangl, Zsofia R; Martinez-de la Torre, Alberto; Griffin, Kevin L; Huntingford, Chris; Hurry, Vaughan; Meir, Patrick; Turnbull, Matthew H; Atkin, Owen K

    2016-04-05

    Plant respiration constitutes a massive carbon flux to the atmosphere, and a major control on the evolution of the global carbon cycle. It therefore has the potential to modulate levels of climate change due to the human burning of fossil fuels. Neither current physiological nor terrestrial biosphere models adequately describe its short-term temperature response, and even minor differences in the shape of the response curve can significantly impact estimates of ecosystem carbon release and/or storage. Given this, it is critical to establish whether there are predictable patterns in the shape of the respiration-temperature response curve, and thus in the intrinsic temperature sensitivity of respiration across the globe. Analyzing measurements in a comprehensive database for 231 species spanning 7 biomes, we demonstrate that temperature-dependent increases in leaf respiration do not follow a commonly used exponential function. Instead, we find a decelerating function as leaves warm, reflecting a declining sensitivity to higher temperatures that is remarkably uniform across all biomes and plant functional types. Such convergence in the temperature sensitivity of leaf respiration suggests that there are universally applicable controls on the temperature response of plant energy metabolism, such that a single new function can predict the temperature dependence of leaf respiration for global vegetation. This simple function enables straightforward description of plant respiration in the land-surface components of coupled earth system models. Our cross-biome analyses shows significant implications for such fluxes in cold climates, generally projecting lower values compared with previous estimates.

  2. Fish community reassembly after a coral mass mortality: higher trophic groups are subject to increased rates of extinction.

    Science.gov (United States)

    Alonso, David; Pinyol-Gallemí, Aleix; Alcoverro, Teresa; Arthur, Rohan

    2015-05-01

    Since Gleason and Clements, our understanding of community dynamics has been influenced by theories emphasising either dispersal or niche assembly as central to community structuring. Determining the relative importance of these processes in structuring real-world communities remains a challenge. We tracked reef fish community reassembly after a catastrophic coral mortality in a relatively unfished archipelago. We revisited the stochastic model underlying MacArthur and Wilson's Island Biogeography Theory, with a simple extension to account for trophic identity. Colonisation and extinction rates calculated from decadal presence-absence data based on (1) species neutrality, (2) trophic identity and (3) site-specificity were used to model post-disturbance reassembly, and compared with empirical observations. Results indicate that species neutrality holds within trophic guilds, and trophic identity significantly increases overall model performance. Strikingly, extinction rates increased clearly with trophic position, indicating that fish communities may be inherently susceptible to trophic downgrading even without targeted fishing of top predators. © 2015 John Wiley & Sons Ltd/CNRS.

  3. Respiration Gates Sensory Input Responses in the Mitral Cell Layer of the Olfactory Bulb

    Science.gov (United States)

    Short, Shaina M.; Morse, Thomas M.; McTavish, Thomas S.; Shepherd, Gordon M.; Verhagen, Justus V.

    2016-01-01

    Respiration plays an essential role in odor processing. Even in the absence of odors, oscillating excitatory and inhibitory activity in the olfactory bulb synchronizes with respiration, commonly resulting in a burst of action potentials in mammalian mitral/tufted cells (MTCs) during the transition from inhalation to exhalation. This excitation is followed by inhibition that quiets MTC activity in both the glomerular and granule cell layers. Odor processing is hypothesized to be modulated by and may even rely on respiration-mediated activity, yet exactly how respiration influences sensory processing by MTCs is still not well understood. By using optogenetics to stimulate discrete sensory inputs in vivo, it was possible to temporally vary the stimulus to occur at unique phases of each respiration. Single unit recordings obtained from the mitral cell layer were used to map spatiotemporal patterns of glomerular evoked responses that were unique to stimulations occurring during periods of inhalation or exhalation. Sensory evoked activity in MTCs was gated to periods outside phasic respiratory mediated firing, causing net shifts in MTC activity across the cycle. In contrast, odor evoked inhibitory responses appear to be permitted throughout the respiratory cycle. Computational models were used to further explore mechanisms of inhibition that can be activated by respiratory activity and influence MTC responses. In silico results indicate that both periglomerular and granule cell inhibition can be activated by respiration to internally gate sensory responses in the olfactory bulb. Both the respiration rate and strength of lateral connectivity influenced inhibitory mechanisms that gate sensory evoked responses. PMID:28005923

  4. Arbuscular mycorrhizal fungi regulate soil respiration and its response to precipitation change in a semiarid steppe.

    Science.gov (United States)

    Zhang, Bingwei; Li, Shan; Chen, Shiping; Ren, Tingting; Yang, Zhiqiang; Zhao, Hanlin; Liang, Yu; Han, Xingguo

    2016-01-28

    Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in Inner Mongolia, China, and soil respiration was continuously measured to investigate the influences of AMF on soil respiration under different precipitation regimes. Results showed that soil respiration was promoted by water addition treatment especially during drought seasons, which induced a nonlinear response of soil respiration to precipitation change. Fungicide application suppressed AMF root colonization without impacts on soil microbes. AMF suppression treatment accelerated soil respiration with 2.7, 28.5 and 37.6 g C m(-2) across three seasons, which were mainly caused by the enhanced heterotrophic component. A steeper response of soil respiration rate to precipitation was found under fungicide application treatments, suggesting a greater dampening effect of AMF on soil carbon release as water availability increased. Our study highlighted the importance of AMF on soil carbon stabilization and sequestration in semiarid steppe ecosystems especially during wet seasons.

  5. Arbuscular mycorrhizal fungi regulate soil respiration and its response to precipitation change in a semiarid steppe

    Science.gov (United States)

    Zhang, Bingwei; Li, Shan; Chen, Shiping; Ren, Tingting; Yang, Zhiqiang; Zhao, Hanlin; Liang, Yu; Han, Xingguo

    2016-01-01

    Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in Inner Mongolia, China, and soil respiration was continuously measured to investigate the influences of AMF on soil respiration under different precipitation regimes. Results showed that soil respiration was promoted by water addition treatment especially during drought seasons, which induced a nonlinear response of soil respiration to precipitation change. Fungicide application suppressed AMF root colonization without impacts on soil microbes. AMF suppression treatment accelerated soil respiration with 2.7, 28.5 and 37.6 g C m-2 across three seasons, which were mainly caused by the enhanced heterotrophic component. A steeper response of soil respiration rate to precipitation was found under fungicide application treatments, suggesting a greater dampening effect of AMF on soil carbon release as water availability increased. Our study highlighted the importance of AMF on soil carbon stabilization and sequestration in semiarid steppe ecosystems especially during wet seasons.

  6. The Active Management of Risk in Multiparous Pregnancy at Term: association between a higher preventive labor induction rate and improved birth outcomes

    Science.gov (United States)

    Nicholson, James M.; Caughey, Aaron; Stenson, Ms. Morghan H.; Cronholm, Peter; Kellar, Lisa; Bennett, Ian; Margo, Katie; Stratton, Joseph

    2009-01-01

    Objective To determine if exposure of multiparous women to a high rate of preventive labor induction was associated with a significantly lower cesarean delivery rate. Study Design Retrospective cohort study involving 123 multiparas, who were exposed to the frequent use of preventive labor induction, and 304 multiparas, who received standard management. Rates of cesarean delivery and other adverse birth outcomes were compared in the two groups. Logistic regression controlled for confounding covariates. Results The exposed group had a lower cesarean delivery rate (aOR 0.09, 0.8% vs. 9.9%, p = 0.02) and a higher uncomplicated vaginal delivery rate (OR 0.53, 78.9% vs. 66.4%, p=0.01). Exposure was not associated with higher rates of other adverse birth outcomes. Conclusion Exposure of multiparas to a high rate of preventive labor induction was significantly associated with improved birth outcomes including a very low cesarean delivery rate. A prospective randomized trial is needed to determine causality. PMID:19254584

  7. [Soil respiration characteristics in winter wheat field in North China Plain].

    Science.gov (United States)

    Chen, Shuyue; Li, Jun; Lu, Peiling; Wang, Yinghong; Yu, Qiang

    2004-09-01

    Experiments were conducted at the Yucheng Comprehensive Experimental Station of the Chinese Academy of Sciences during 2002-2003 to investigate the respiration of a pulverous sandstone soil under cultivation of winter wheat over a growth season. The effluent CO2 was collected and analyzed by the static-chamber/gas chromatography (GC) method at a frequency of once a week in spring and autumn, once two weeks in winter, twice a week for straw manure treatment, once a week for no straw manure treatment and nitrogen fertilization treatment in summer. The results indicated that diurnal variation of soil respiration rate showed a single peak in typical winter wheat farmlands in the North China Plain, and reached the highest at about 13 o'clock, and the lowest at about 4 o'clock in the early morning. In winter wheat growth season, the soil respiration rate was 31.23-606.85 mg x m(-2) x h(-1) under straw manure, 28.99-549.66 x m(-2) x h(-1) under no straw manure, 10.46-590.86 mg x m(-2) x h(-1) in N0, 16.11-349.88 mg x m(-2) x h(-1) in N100, 12.25-415.00 mg x m(-2) x h(-1) in N200, and 23.01-410.58 mg x m(-2) x h(-1) in N300, showing a similar seasonal variation tendency with soil temperature. Among all treatments, the straw manure had the most distinct soil respiration, though the soil respiration also increased slightly with increasing nitrogen fertilization. Soil respiration increased exponentially with increasing soil temperature, and the correlation of soil temperature at the depth of 5 cm was the best. This relationship was usually described with the Q10 model, which represented the sensitivity of soil respiration to temperature. Q10 was not a fixed value, which varied with the depth at which the temperature was measured and the depth of the active soil layer and soil temperature. At same time, the Q10 value decreased with increasing soil temperature. Soil water content was another important factor affecting soil respiration rate, but in this region, the relationship

  8. Assessing SOC labile fractions through respiration test, density-size fractionation and thermal analysis - A comparison of methods

    Science.gov (United States)

    Soucemarianadin, Laure; Cécillon, Lauric; Chenu, Claire; Baudin, François; Nicolas, Manuel; Savignac, Florence; Barré, Pierre

    2017-04-01

    ) were only weakly positively correlated (Spearman's ρ = 0.26, n = 93). Similarly, soil respiration had only a weak negative correlation (Spearman's ρ = -0.24, n = 93; ρ = -0.33, n = 222) with the RE6 parameter T50 CH pyrolysis. This parameter, previously used as an indicator of labile SOC (Gregorich et al., 2015), represents the temperature at which 50% of the OM was pyrolyzed to effluents (mainly hydrocarbons) during the pyrolysis phase of RE6. Conversely, POC content (% of total SOC) showed a higher negative correlation with T50 CH pyrolysis (ρ = -0.66, n = 93; ρ = -0.65, n = 103) and was positively and negatively correlated to the hydrogen index, HI (mg HC/g TOC; ρ = 0.56/0.53) and the oxygen index, OI (mg CO2/g TOC; ρ = -0.63/-0.62) respectively. Our results showed that RE6 results are consistent with respiration and fractionation results: SOC with higher respiration rate and higher POC content burns at a lower temperature. RE6 thermal analysis could therefore be viewed as a useful fast and cost effective alternative to more time-consuming methods used in SOM fractions determination. Barré, P. et al. Biogeochemistry 2016, 1-12, 130. Gregorich, E.G. et al. Soil Biol. Biochem. 2015, 182-191, 91.

  9. Potential impact on HIV incidence of higher HIV testing rates and earlier antiretroviral therapy initiation in MSM

    DEFF Research Database (Denmark)

    Phillips, Andrew N; Cambiano, Valentina; Miners, Alec

    2015-01-01

    count 350/μl. We investigated what would be required to reduce HIV incidence in MSM to below 1 per 1000 person-years (i.e. cost-effective. METHODS: A dynamic, individual-based simulation model was calibrated to multiple data sources...... with viral suppression to 80%, and it would be 90%, if ART is initiated at diagnosis. The scenarios required for such a policy to be cost-effective are presented. CONCLUSION: This analysis provides targets for the proportion of all HIV-positive MSM with viral suppression required to achieve substantial......BACKGROUND: Increased rates of testing, with early antiretroviral therapy (ART) initiation, represent a key potential HIV-prevention approach. Currently, in MSM in the United Kingdom, it is estimated that 36% are diagnosed by 1 year from infection, and the ART initiation threshold is at CD4 cell...

  10. PCR reveals significantly higher rates of Trypanosoma cruzi infection than microscopy in the Chagas vector, Triatoma infestans: High rates found in Chuquisaca, Bolivia

    Directory of Open Access Journals (Sweden)

    Lucero David E

    2007-06-01

    Full Text Available Abstract Background The Andean valleys of Bolivia are the only reported location of sylvatic Triatoma infestans, the main vector of Chagas disease in this country, and the high human prevalence of Trypanosoma cruzi infection in this region is hypothesized to result from the ability of vectors to persist in domestic, peri-domestic, and sylvatic environments. Determination of the rate of Trypanosoma infection in its triatomine vectors is an important element in programs directed at reducing human infections. Traditionally, T. cruzi has been detected in insect vectors by direct microscopic examination of extruded feces, or dissection and analysis of the entire bug. Although this technique has proven to be useful, several drawbacks related to its sensitivity especially in the case of small instars and applicability to large numbers of insects and dead specimens have motivated researchers to look for a molecular assay based on the polymerase chain reaction (PCR as an alternative for parasitic detection of T. cruzi infection in vectors. In the work presented here, we have compared a PCR assay and direct microscopic observation for diagnosis of T. cruzi infection in T. infestans collected in the field from five localities and four habitats in Chuquisaca, Bolivia. The efficacy of the methods was compared across nymphal stages, localities and habitats. Methods We examined 152 nymph and adult T. infestans collected from rural areas in the department of Chuquisaca, Bolivia. For microscopic observation, a few drops of rectal content obtained by abdominal extrusion were diluted with saline solution and compressed between a slide and a cover slip. The presence of motile parasites in 50 microscopic fields was registered using 400× magnification. For the molecular analysis, dissection of the posterior part of the abdomen of each insect followed by DNA extraction and PCR amplification was performed using the TCZ1 (5' – CGA GCT CTT GCC CAC ACG GGT GCT – 3

  11. SOME METHODIC ASPECTS OF VOCAL RESPIRATION WITHIN ACADEMIC SINGING TEACHING

    Directory of Open Access Journals (Sweden)

    AGA LUDMILA

    2015-12-01

    Full Text Available This article presents the author’s reflections on the methodical problems of vocal respiration treated by Ludmila Aga as one of the essential elements of vocal technique. Based on her own rich experience as opera soloist and vocal teacher, the author reviews some theoretical principles which treat this problem. Besides, L. Aga proposes some helpful exercises for developing vocal respiration abilities. The article combines data from physiology, history and the theory of performing arts, methods of singing. Having an applied character, this work might be helpful for the singing teachers from the colleges and higher instituti­ons of music proile, as well as for the students of the Academic Singing Department.

  12. Effect of temperature during ion sputtering on the surface segregation rate of antimony in an iron-antimony alloy at higher temperatures

    International Nuclear Information System (INIS)

    Oku, M.; Hirokawa, K.; Kimura, H.; Suzuki, S.

    1986-01-01

    The surface segregation of antimony in an iron-0.23 at% antimony alloy was studied by XPS. The segregation rate in the temperature range between 800 and 900 K depends on the temperature during sputtering with argon ion of kinetic energy of 1 keV. The sputtering at room temperature or 473 K gives higher values of the segregation rate than those at 673 K. Both cases give the activation energy of 170 kJmol -1 for the surface segregation rate. The segregation of antimony is not observed after the sample is heated at 1000 K. (author)

  13. Loose regulation of medical marijuana programs associated with higher rates of adult marijuana use but not cannabis use disorder.

    Science.gov (United States)

    Williams, Arthur Robin; Santaella-Tenorio, Julian; Mauro, Christine M; Levin, Frances R; Martins, Silvia S

    2017-11-01

    Most US states have passed medical marijuana laws (MMLs), with great variation in program regulation impacting enrollment rates. We aimed to compare changes in rates of marijuana use, heavy use and cannabis use disorder across age groups while accounting for whether states enacted medicalized (highly regulated) or non-medical mml programs. Difference-in-differences estimates with time-varying state-level MML coded by program type (medicalized versus non-medical). Multi-level linear regression models adjusted for state-level random effects and covariates as well as historical trends in use. Nation-wide cross-sectional survey data from the US National Survey of Drug Use and Health (NSDUH) restricted use data portal aggregated at the state level. Participants comprised 2004-13 NSDUH respondents (n ~ 67 500/year); age groups 12-17, 18-25 and 26+ years. States had implemented eight medicalized and 15 non-medical MML programs. Primary outcome measures included (1) active (past-month) marijuana use; (2) heavy use (> 300 days/year); and (3) cannabis use disorder diagnosis, based on DSM-IV criteria. Covariates included program type, age group and state-level characteristics throughout the study period. Adults 26+ years of age living in states with non-medical MML programs increased past-month marijuana use 1.46% (from 4.13 to 6.59%, P = 0.01), skewing towards greater heavy marijuana by 2.36% (from 14.94 to 17.30, P = 0.09) after MMLs were enacted. However, no associated increase in the prevalence of cannabis use disorder was found during the study period. Our findings do not show increases in prevalence of marijuana use among adults in states with medicalized MML programs. Additionally, there were no increases in adolescent or young adult marijuana outcomes following MML passage, irrespective of program type. Non-medical marijuana laws enacted in US states are associated with increased marijuana use, but only among adults aged 26+ years. Researchers and

  14. Internal respiration of Amazon tree stems greatly exceeds external CO2 efflux

    Directory of Open Access Journals (Sweden)

    J. Q. Chambers

    2012-12-01

    Full Text Available Respiration in tree stems is an important component of forest carbon balance. The rate of CO2 efflux from the stem has often been assumed to be a measure of stem respiration. However, recent work in temperate forests has demonstrated that stem CO2 efflux can either overestimate or underestimate respiration rate because of emission or removal of CO2 by transport in xylem water. Here, we studied gas exchange from stems of tropical forest trees using a new approach to better understand respiration in an ecosystem that plays a key role in the global carbon cycle. Our main questions were (1 is internal CO2 transport important in tropical trees, and, if so, (2 does this transport result in net release of CO2 respired in the roots at the stem, or does it cause the opposite effect of net removal of stem-respired CO2? To answer these questions, we measured the ratio of stem CO2 efflux to O2 influx. This ratio, defined here as apparent respiratory quotient (ARQ, is expected to equal 1.0 if carbohydrates are the substrate for respiration, and the net transport of CO2 in the xylem water is negligible. Using a stem chamber approach to quantifying ARQ, we found values of 0.66 ± 0.18. These low ARQ values indicate that a large portion of respired CO2 (~ 35% is not emitted locally, and is probably transported upward in the stem. ARQ values of 0.21 ± 0.10 were found for the steady-state gas concentration within the stem, sampled by in-stem equilibration probes. These lower values may result from the proximity to the xylem water stream. In contrast, we found ARQ values of 1.00 ± 0.13 for soil respiration. Our results indicate the existence of a considerable internal flux of CO2 in the stems of tropical trees. If the transported CO2 is used in the canopy as a substrate for photosynthesis, it could account for up to 10% of the C fixed by the tree, and perhaps serve as a mechanism that buffers the response of the tree to changing CO2 levels. Our results also

  15. [Effects of antimicrobial drugs on soil microbial respiration].

    Science.gov (United States)

    Liu, Feng; Ying, Guang-Guo; Zhou, Qi-Xing; Tao, Ran; Su, Hao-Chang; Li, Xu

    2009-05-15

    The effects on soil microbial respiration of sulfonamides, tetracyclines, macrolides and so on were studied using the direct absorption method. The results show sulfamethazine, sulfamethoxazole, chlortetracycline, tetracycline, tylosin and trimethoprim inhibit soil respiration 34.33%, 34.43%, 2.71%, 3.08%, 7.13%, 38.08% respectively. Sulfamethoxazole and trimethoprim have the highest inhibition rates among all the antibiotics. In early incubation period (0-2 d), the concentrations above 10 mg x kg(-1) of sulfamethazine, sulfamethoxazole and trimethoprim remarkably decrease soil CO2 emission. The effects of these antibiotics vary with their concentrations too. Sulfamethoxazole and trimethoprim show good dose-response relationships. According to the standard of pesticide safety evaluation protocol, the six antibiotics pose a little risk to soil microbial environment.

  16. Being born under adverse economic conditions leads to a higher cardiovascular mortality rate later in life: evidence based on individuals born at different stages of the business cycle

    DEFF Research Database (Denmark)

    van den Berg, Gerard J; Doblhammer-Reiter, Gabriele; Christensen, Kaare

    2011-01-01

    since the 1870s and including the cause of death. To capture exogenous variation of conditions early in life, we use the state of the business cycle around birth. We find significant negative effects of economic conditions around birth on the individual CV mortality rate at higher ages...

  17. Nicotinamide supplementation phenocopies SIR2 inactivation by modulating carbon metabolism and respiration during yeast chronological aging.

    Science.gov (United States)

    Orlandi, Ivan; Pellegrino Coppola, Damiano; Strippoli, Maurizio; Ronzulli, Rossella; Vai, Marina

    2017-01-01

    Nicotinamide (NAM), a form of vitamin B 3 , is a byproduct and noncompetitive inhibitor of the deacetylation reaction catalyzed by Sirtuins. These represent a family of evolutionarily conserved NAD + -dependent deacetylases that are well-known critical regulators of metabolism and aging and whose founding member is Sir2 of Saccharomyces cerevisiae. Here, we investigated the effects of NAM supplementation in the context of yeast chronological aging, the established model for studying aging of postmitotic quiescent mammalian cells. Our data show that NAM supplementation at the diauxic shift results in a phenocopy of chronologically aging sir2Δ cells. In fact, NAM-supplemented cells display the same chronological lifespan extension both in expired medium and extreme Calorie Restriction. Furthermore, NAM allows the cells to push their metabolism toward the same outcomes of sir2Δ cells by elevating the level of the acetylated Pck1. Both these cells have the same metabolic changes that concern not only anabolic pathways such as an increased gluconeogenesis but also respiratory activity in terms both of respiratory rate and state of respiration. In particular, they have a higher respiratory reserve capacity and a lower non-phosphorylating respiration that in concert with a low burden of superoxide anions can affect positively chronological aging. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Boarding is associated with higher rates of medication delays and adverse events but fewer laboratory-related delays.

    Science.gov (United States)

    Sri-On, Jiraporn; Chang, Yuchiao; Curley, David P; Camargo, Carlos A; Weissman, Joel S; Singer, Sara J; Liu, Shan W

    2014-09-01

    Hospital crowding and emergency department (ED) boarding are large and growing problems. To date, there has been a paucity of information regarding the quality of care received by patients boarding in the ED compared with the care received by patients on an inpatient unit. We compared the rate of delays and adverse events at the event level that occur while boarding in the ED vs while on an inpatient unit. This study was a secondary analysis of data from medical record review and administrative databases at 2 urban academic teaching hospitals from August 1, 2004, through January 31, 2005. We measured delayed repeat cardiac enzymes, delayed partial thromboplastin time level checks, delayed antibiotic administration, delayed administration of home medications, and adverse events. We compared the incidence of events during ED boarding vs while on an inpatient unit. Among 1431 patient medical records, we identified 1016 events. Emergency department boarding was associated with an increased risk of home medication delays (risk ratio [RR], 1.54; 95% confidence interval [CI], 1.26-1.88), delayed antibiotic administration (RR, 2.49; 95% CI, 1.72-3.52), and adverse events (RR, 2.36; 95% CI, 1.15-4.72). On the contrary, ED boarding was associated with fewer delays in repeat cardiac enzymes (RR, 0.17; 95% CI, 0.09-0.27) and delayed partial thromboplastin time checks (RR, 0.54; 95% CI, 0.27-0.96). Compared with inpatient units, ED boarding was associated with more medication-related delays and adverse events but fewer laboratory-related delays. Until we can eliminate ED boarding, it is critical to identify areas for improvement. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Low-birthweight rates higher among Bangladeshi neonates measured during active birth surveillance compared to national survey data.

    Science.gov (United States)

    Klemm, Rolf D W; Merrill, Rebecca D; Wu, Lee; Shamim, Abu Ahmed; Ali, Hasmot; Labrique, Alain; Christian, Parul; West, Keith P

    2015-10-01

    Birth size is an important gauge of fetal and neonatal health. Birth size measurements were collected within 72 h of life for 16 290 live born, singleton infants in rural Bangladesh from 2004 to 2007. Gestational age was calculated based on the date of last menstrual period. Newborns were classified as small-for-gestational age (SGA) based on a birthweight below the 10th percentile for gestational age, using three sets of US reference data. Birth size distributions were explored based on raw values as well as after z-score standardisation in reference to World Health Organization (WHO) 2006 growth standards. Mean (SD) birthweight (g), length (cm) and head circumference (cm) measurements, completed within [median (25th, 75th percentile)] 15 (8, 23) h of life, were 2433 (425), 46.4 (2.4) and 32.4 (1.6), respectively. Twenty-two per cent were born preterm. Over one-half (55.3%) of infants were born low birthweight; 46.6%, 37.0% and 33.6% had a weight, length and head circumference below -2 z-scores of the WHO growth standard at birth; and 70.9%, 72.2% and 59.8% were SGA for weight based on Alexander et al., Oken et al. and Olsen et al. references, respectively. Infants in this typical rural Bangladesh setting were commonly born small, reflecting a high burden of fetal growth restriction and preterm birth. Our findings, produced by active birth surveillance, suggest that low birthweight is far more common than suggested by cross-sectional survey estimates. Interventions that improve fetal growth during pregnancy may have the largest impact on reducing SGA rates. © 2013 John Wiley & Sons Ltd.

  20. Numerical and experimental investigation of the bell-mouth inlet design of a centrifugal fan for higher internal flow rate

    International Nuclear Information System (INIS)

    Kim, Sang Hyeon; Heo, Seung; Cheong, Cheolung; Kim, Tae Hoon

    2013-01-01

    The energy efficiency of a household refrigerator is one of the most critical characteristics considered by manufacturers and consumers. Numerous studies in various fields have been conducted to increase energy efficiency. One of the most efficient methods to reduce the energy consumption of a refrigerator is by improving the performance of fans inside the refrigerator. A number of studies reported various ways to enhance fan performance. However, the majority of these studies focused solely on the fan and did not consider the working environment of the fan, such as the inlet and outlet flow characteristics. The expected performance of fans developed without consideration of these characteristics cannot be determined because complex inlet and outlet flow passage could adversely affect performance. This study investigates the effects of the design of the bell-mouth inlet on the performance of a centrifugal fan in a household refrigerator. In preliminary numerical studies, significant flow loss is identified through the bell-mouth inlet in the target fan system. Several design factors such as tip clearance, inner fence, motor-box struts, and guide vane are proposed to resolve these flow losses. The effects of these factors on fan performance are investigated using computational fluid dynamics techniques to solve incompressible Reynolds-averaged Navier-Stokes equations for predicting the circulating flow of the fan. Experiments are then performed to validate the numerical predictions. Results indicate that four design factors positively affect fan performance in terms of flow rate. The guide vane is the most effective design factor to consider for improving fan performance. Further studies are conducted to investigate the detailed effects of the guide vane by varying its install angle, install location, height, and length. These studies determine the optimum design of the guide vane to achieve the highest performance of the fan and the related flow characteristics

  1. Numerical and experimental investigation of the bell-mouth inlet design of a centrifugal fan for higher internal flow rate

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Hyeon; Heo, Seung; Cheong, Cheolung [Pusan National University, Busan (Korea, Republic of); Kim, Tae Hoon [Refrigeration Division, Changwon (Korea, Republic of)

    2013-08-15

    The energy efficiency of a household refrigerator is one of the most critical characteristics considered by manufacturers and consumers. Numerous studies in various fields have been conducted to increase energy efficiency. One of the most efficient methods to reduce the energy consumption of a refrigerator is by improving the performance of fans inside the refrigerator. A number of studies reported various ways to enhance fan performance. However, the majority of these studies focused solely on the fan and did not consider the working environment of the fan, such as the inlet and outlet flow characteristics. The expected performance of fans developed without consideration of these characteristics cannot be determined because complex inlet and outlet flow passage could adversely affect performance. This study investigates the effects of the design of the bell-mouth inlet on the performance of a centrifugal fan in a household refrigerator. In preliminary numerical studies, significant flow loss is identified through the bell-mouth inlet in the target fan system. Several design factors such as tip clearance, inner fence, motor-box struts, and guide vane are proposed to resolve these flow losses. The effects of these factors on fan performance are investigated using computational fluid dynamics techniques to solve incompressible Reynolds-averaged Navier-Stokes equations for predicting the circulating flow of the fan. Experiments are then performed to validate the numerical predictions. Results indicate that four design factors positively affect fan performance in terms of flow rate. The guide vane is the most effective design factor to consider for improving fan performance. Further studies are conducted to investigate the detailed effects of the guide vane by varying its install angle, install location, height, and length. These studies determine the optimum design of the guide vane to achieve the highest performance of the fan and the related flow characteristics

  2. A Time-Frequency Respiration Tracking System using Non-Contact Bed Sensors with Harmonic Artifact Rejection

    Science.gov (United States)

    Beattie, Zachary T.; Jacobs, Peter G.; Riley, Thomas C.; Hagen, Chad C.

    2015-01-01

    Sleep apnea is a serious health condition that affects many individuals and has been associated with serious health conditions such as cardiovascular disease. Clinical diagnosis of sleep apnea requires that a patient spend the night in a sleep clinic while being wired up to numerous obtrusive sensors. We are developing a system that utilizes respiration rate and breathing amplitude inferred from non-contact bed sensors (i.e. load cells placed under bed supports) to detect sleep apnea. Multi-harmonic artifacts generated either biologically or as a result of the impulse response of the bed have made it challenging to track respiration rate and amplitude with high resolution in time. In this paper, we present an algorithm that can accurately track respiration on a second-by-second basis while removing noise harmonics. The algorithm is tested using data collected from 5 patients during overnight sleep studies. Respiration rate is compared with polysomnography estimations of respiration rate estimated by a technician following clinical standards. Results indicate that certain subjects exhibit a large harmonic component of their breathing signal that can be removed by our algorithm. When compared with technician transcribed respiration rates using polysomnography signals, we demonstrate improved accuracy of respiration rate tracking using harmonic artifact rejection (mean error: 0.18 breaths/minute) over tracking not using harmonic artifact rejection (mean error: −2.74 breaths/minute). PMID:26738176

  3. Organic fertilizer application increases the soil respiration and net ecosystem carbon dioxide absorption of paddy fields under water-saving irrigation.

    Science.gov (United States)

    Yang, Shihong; Xiao, Ya Nan; Xu, Junzeng

    2018-04-01

    Quantifying carbon sequestration in paddy soil is necessary to understand the effect of agricultural practices on carbon cycles. The objective of this study was to assess the effect of organic fertilizer addition (MF) on the soil respiration and net ecosystem carbon dioxide (CO 2 ) absorption of paddy fields under water-saving irrigation (CI) in the Taihu Lake Region of China during the 2014 and 2015 rice-growing seasons. Compared with the traditional fertilizer and water management (FC), the joint regulation of CI and MF (CM) significantly increased the rice yields and irrigation water use efficiencies of paddy fields by 4.02~5.08 and 83.54~109.97% (p < 0.05). The effects of organic fertilizer addition on soil respiration and net ecosystem CO 2 absorption rates showed inter-annual differences. CM paddy fields showed a higher soil respiration and net CO 2 absorption rates during some periods of the rice growth stage in the first year and during most periods of the rice growth stage in the second year. These fields also had significantly higher total CO 2 emission through soil respiration (total R soil ) and total net CO 2 absorption compared with FC paddy fields (p < 0.05). The total R soil and net ecosystem CO 2 absorption of CM paddy fields were 67.39~91.55 and 129.41~113.75 mol m -2 , which were 27.66~135.52 and 12.96~31.66% higher than those of FC paddy fields. The interaction between water and fertilizer management had significant effects on total net ecosystem CO 2 absorption. The frequent alternate wet-dry cycles of CI paddy fields increased the soil respiration and reduced the net CO 2 absorption. Organic fertilizer promoted the soil respiration of paddy soil but also increased its net CO 2 absorption and organic carbon content. Therefore, the joint regulation of water-saving irrigation and organic fertilizer is an effective measure for maintaining yield, increasing irrigation water use efficiency, mitigating CO 2 emission, and promoting paddy

  4. Linear programming model can explain respiration of fermentation products

    Science.gov (United States)

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the “Warburg effect”. The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited. PMID:29415045

  5. Linear programming model can explain respiration of fermentation products.

    Science.gov (United States)

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan; Boley, Daniel

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the "Warburg effect". The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited.

  6. Comparing organic versus conventional soil management on soil respiration [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Bence Mátyás

    2018-03-01

    Full Text Available Soil management has great potential to affect soil respiration. In this study, we investigated the effects of organic versus conventional soil management on soil respiration.  We measured the main soil physical-chemical properties from conventional and organic managed soil in Ecuador. Soil respiration was determined using alkaline absorption according to Witkamp.  Soil properties such as organic matter, nitrogen, and humidity, were comparable between conventional and organic soils in the present study, and in a further analysis there was no statically significant correlation with soil respiration. Therefore, even though organic farmers tend to apply more organic material to their fields, but this did not result in a significantly higher CO2 production in their soils in the present study.

  7. Significance of cold-season respiration and photosynthesis in a subarctic heath ecosystem in Northern Sweden

    DEFF Research Database (Denmark)

    Larsen, Klaus Steenberg; Ibrom, Andreas; Jonasson, S.

    2007-01-01

    While substantial cold-season respiration has been documented in most arctic and alpine ecosystems in recent years, the significance of cold-season photosynthesis in these biomes is still believed to be small. In a mesic, subartic heath during both the cold and warm season, we measured in situ...... ecosystem respiration and photosynthesis with a chamber technique at ambient conditions and at artificially, increased frequency of freeze-thaw (FT) cycles during fall and spring. We fitted the measured ecosystem exchange rates to respiration and photosynthesis models with R-2-values ranging from 0.81 to 0.......85. As expected, estimated cold-season (October, November, April and May) respiration was significant and accounted for at least 22% of the annual respiratory CO2 flux. More surprisingly, estimated photosynthesis during this period accounted for up to 19% of the annual gross CO2 uptake, suggesting that cold...

  8. Separating rhizosphere respiration from total soil respiration in two larch plantations in northeastern China.

    Science.gov (United States)

    Jiang, Lifen; Shi, Fuchen; Li, Bo; Luo, Yiqi; Chen, Jiquan; Chen, Jiakuan

    2005-09-01

    The potential capacity of soil to sequester carbon in response to global warming is strongly regulated by the ratio of rhizosphere respiration to respiration by soil microbial decomposers, because of their different temperature sensitivities. To quantify relative contributions of rhizosphere respiration to total soil respiration as influenced by forest stand development, we conducted a trenching study in two larch (Larix gmelini (Rupr.) Rupr.) plantations, aged 17 and 31 years, in northeastern China. Four plots in each plantation were randomly selected and trenched in early May 2001. Soil surface CO2 effluxes both inside and outside the plots were measured from May 2001 to August 2002. Soil respiration (i.e., the CO2 effluxes outside the trenched plots) varied similarly in the two plantations from 0.8 micromol m(-2) s(-1) in winter to 6.0 micromol m(-2) s(-1) in summer. Rhizosphere respiration (i.e., CO2 efflux outside the trenched plots minus that inside the plots) varied from 0.2 to 2.0 micromol m(-2) s(-1) in the old forest and from 0.3 to 4.0 micromol m(-2) s(-1) in the young forest over the seasons. Rhizosphere respiration, on average, accounted for 25% of soil respiration in the old forest and 65% in the young forest. Rhizosphere and soil respiration were significantly correlated with soil temperature but not with soil water content. We conclude that the role forests play in regulating climate change may depend on their age.

  9. 42 CFR 84.134 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.134... Respirators § 84.134 Respirator containers; minimum requirements. Supplied-air respirators shall be equipped with a substantial, durable container bearing markings which show the applicant's name, the type and...

  10. 42 CFR 84.197 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.197... Cartridge Respirators § 84.197 Respirator containers; minimum requirements. Respirators shall be equipped with a substantial, durable container bearing markings which show the applicant's name, the type and...

  11. 42 CFR 84.174 - Respirator containers; minimum requirements.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Respirator containers; minimum requirements. 84.174... Air-Purifying Particulate Respirators § 84.174 Respirator containers; minimum requirements. (a) Except..., durable container bearing markings which show the applicant's name, the type of respirator it contains...

  12. Respiration in heterotrophic unicellular eukaryotic organisms.

    Science.gov (United States)

    Fenchel, Tom

    2014-08-01

    Surface:volume quotient, mitochondrial volume fraction, and their distribution within cells were investigated and oxygen gradients within and outside cells were modelled. Cell surface increases allometrically with cell size. Mitochondrial volume fraction is invariant with cell size and constitutes about 10% and mitochondria are predominantly found close to the outer membrane. The results predict that for small and medium sized protozoa maximum respiration rates should be proportional to cell volume (scaling exponent ≈1) and access to intracellular O2 is not limiting except at very low ambient O2-tensions. Available data do not contradict this and some evidence supports this interpretation. Cell size is ultimately limited because an increasing fraction of the mitochondria becomes exposed to near anoxic conditions with increasing cell size. The fact that mitochondria cluster close to the cell surface and the allometric change in cell shape with increasing cell size alleviates the limitation of aerobic life at low ambient O2-tension and for large cell size. Copyright © 2014 Elsevier GmbH. All rights reserved.

  13. Soil respiration in typical plant communities in the wetland surrounding the high-salinity Ebinur Lake

    Science.gov (United States)

    Li, Yanhong; Zhao, Mingliang; Li, Fadong

    2018-03-01

    Soil respiration in wetlands surrounding lakes is a vital component of the soil carbon cycle in arid regions. However, information remains limited on the soil respiration around highly saline lakes during the plant growing season. Here, we aimed to evaluate diurnal and seasonal variation in soil respiration to elucidate the controlling factors in the wetland of Ebinur Lake, Xinjiang Uygur Autonomous Region, western China. We used a soil carbon flux automatic analyzer (LI-840A) to measure soil respiration rates during the growing season (April to November) in two fields covered by reeds and tamarisk and one field with no vegetation (bare soil) from 2015 to 2016. The results showed a single peak in the diurnal pattern of soil respiration from 11:00 to 17:00 for plots covered in reeds, tamarisk, and bare soil, with minimum values being detected from 03:00 to 07:00. During the growing season, the soil respiration of reeds and tamarisk peaked during the thriving period (4.16 and 3.75 mmol•m-2•s-1, respectively), while that of bare soil peaked during the intermediate growth period (0.74 mmol•m-2•s-1). The soil respiration in all three plots was lowest during the wintering period (0.08, 0.09, and-0.87 mmol•m-2•s-1, respectively). Air temperature and relative humidity significantly influenced soil respiration. A significant linear relationship was detected between soil respiration and soil temperature for reeds, tamarisk, and bare soil. The average Q10 of reeds and tamarisk were larger than that of bare soil. However, soil moisture content was not the main factor controlling soil respiration. Soil respiration was negatively correlated with soil pH and soil salinity in all three plot types. In contrast, soil respiration was positively correlated with organic carbon. Overall, CO2 emissions and greenhouse gases had a relatively weak effect on the wetlands surrounding the highly saline Ebinur Lake.

  14. Impact of Altered Precipitation Patterns on Plant Productivity and Soil Respiration in a Northern Great Plains Grassland

    Science.gov (United States)

    Haase, L.; Flanagan, L. B.

    2017-12-01

    Precipitation patterns are expected to shift towards larger but fewer rain events, with longer intermittent dry periods, associated with climate change. The larger rain events may compensate for and help to mitigate climate change effects on key ecosystem functions such as plant productivity and soil respiration in semi-arid grasslands. We experimentally manipulated the amount and frequency of simulated precipitation added to trenched, treatment plots that were covered by rain shelters, and measured the response in plant productivity and soil respiration in a native, grassland ecosystem near Lethbridge, Alberta. We compared the observed responses to the predictions of a conceptual ecosystem response model developed by Knapp et al. 2008 (BioScience 58: 811-821). Two experiments were conducted during 14 weeks of the growing season from May-August. The first experiment (normal amount) applied total growing season precipitation of 180 mm (climate normal), and the second experiment (reduced amount) applied total precipitation of 90 mm. In both experiments, precipitation was applied at two frequencies, 1 rain event every week (normal frequency) and 1 rain event every two weeks (reduced frequency). In the normal amount experiment, the average rain event was 12.8 mm for the normal frequency treatment and 25.8 mm for the reduced frequency treatment. In the reduced amount experiment, the average rain event was 6.4 mm for the normal frequency treatment and 12.8 mm for the reduced frequency treatment. We hypothesized that larger but fewer rain events would result in increased plant productivity and soil respiration for both experiments. Plant greenness values calculated from digital photographs were used as a proxy for plant productivity, and showed significantly higher values for the normal vs. reduced amount experiment. Soil respiration rate also showed significantly higher values for the normal vs. reduced amount experiment. No significant treatment effect could be detected

  15. APPRAISAL OF STUDENT RATING AS A MEASURE TO MANAGE THE QUALITY OF HIGHER EDUCATION IN INDIA: AN INSTITUTIONAL STUDY USING SIX SIGMA MODEL APPROACH

    Directory of Open Access Journals (Sweden)

    Arun Vijay

    2013-12-01

    Full Text Available Students' rating of teaching is one of the most widely accepted methods of measuring the quality in Higher Education worldwide. The overall experience gained by the students during their academic journey in their respective college is a key factor to determine the Institutional Quality. This study was conducted among the Physical Therapy students with an objective to capture the overall experience related to various aspects of their Academic environment including teaching and learning process adopted in their college. To facilitate that, a unique questionnaire called,"Academic Environment Evaluation Questionnaire (AEEQ was developed covering all the important teaching elements of the Higher Education Institutions. The students' opinion was captured and analyzed through six sigma analytical tool using Poisson distribution model. From the non-conformance level captured through the responses from the students about the various categories of teaching and learning elements, the corresponding Sigma rating for each teaching element was measured. Accordingly, a six point Quality rating system was developed customizing to each sigma values. This study brings a new, innovative student driven Quality rating system for the Higher Education Institutions in India.

  16. [A comparative study on soil respiration between grazing and fenced typical Leymus chinensis steppe, Inner Mongolia].

    Science.gov (United States)

    Jia, Bingrui; Zhou, Guangsheng; Wang, Fengyu; Wang, Yuhui

    2004-09-01

    With enclosed chamber Method, this paper studied the soil respiration in grazing and fenced typical Leymus chinensis steppes, Inner Mongolia, and its relationships with environmental factors. The results showed that the daily pattern of soil respiration could be expressed as a one-humped curve, and the highest values appeared at 13:00-15:00 in the fenced and grazing plots. The diurnal dynamics of soil respiration mainly depended on the surface temperature at the fenced plots and the soil temperature at 5 cm depth at the grazing plots. In June and July, the average soil respiration rate was 2.7 times greater at the fenced plots than that at the grazing plots, while the difference was not distinct in August and September, which was similar with the change of the belowground biomass. The reason was probably that the plant was influenced differently in different phenological phases by grazing and the change of environmental factors. It showed that human activity may not result in the increase of soil respiration rate. The seasonal dynamics of soil respiration was closely correlated with soil water content at the 0-10 cm depth at the fenced and grazing sites, and the maximum R2 was 0.853 and 0.741, respectively. The difference was that the correlation of soil respiration seasonal dynamics with soil water content was larger at the fenced plots than at the grazing plots. The correlations of soil respiration diurnal and seasonal dynamics with temperature and soil water content at lower profiles were larger than those at deeper profiles at the fenced and grazing sites.

  17. Respiration of Nitrate and Nitrite.

    Science.gov (United States)

    Cole, Jeffrey A; Richardson, David J

    2008-09-01

    Nitrate reduction to ammonia via nitrite occurs widely as an anabolic process through which bacteria, archaea, and plants can assimilate nitrate into cellular biomass. Escherichia coli and related enteric bacteria can couple the eight-electron reduction of nitrate to ammonium to growth by coupling the nitrate and nitrite reductases involved to energy-conserving respiratory electron transport systems. In global terms, the respiratory reduction of nitrate to ammonium dominates nitrate and nitrite reduction in many electron-rich environments such as anoxic marine sediments and sulfide-rich thermal vents, the human gastrointestinal tract, and the bodies of warm-blooded animals. This review reviews the regulation and enzymology of this process in E. coli and, where relevant detail is available, also in Salmonella and draws comparisons with and implications for the process in other bacteria where it is pertinent to do so. Fatty acids may be present in high levels in many of the natural environments of E. coli and Salmonella in which oxygen is limited but nitrate is available to support respiration. In E. coli, nitrate reduction in the periplasm involves the products of two seven-gene operons, napFDAGHBC, encoding the periplasmic nitrate reductase, and nrfABCDEFG, encoding the periplasmic nitrite reductase. No bacterium has yet been shown to couple a periplasmic nitrate reductase solely to the cytoplasmic nitrite reductase NirB. The cytoplasmic pathway for nitrate reduction to ammonia is restricted almost exclusively to a few groups of facultative anaerobic bacteria that encounter high concentrations of environmental nitrate.

  18. Effect of mercuric ions on growth and respiration of two coagulase-positive Staphylococcus aureus strains

    Energy Technology Data Exchange (ETDEWEB)

    Tynecka, Z; Szymona, O

    1966-01-01

    Sensitivity toward HgCl/sub 2/ of two coagulase-positive Staphylococcus aureus strains has been studied. Strain 15 proved to be over 10 times more resistant to HgCl/sub 2/ in the growth test than strain 31. The former showed also higher rates of endogenous respiration and more actively oxidized glucose in presence of HgCl/sub 2/. Strain 31 grew better in absence of HgCl/sub 2/ but readily underwent inhibition both in the growth and glucose oxidation experiment. Strain 31 was, however, less sensitive to HgCl/sub 2/, as detected by methylene blue reduction in presence of malate and succinate as substrates. Cysteine largely reversed the inhibitory effect of mercuric ions. Experiments with radioactive Hg/sup 203/Cl/sub 2/ did not prove the sensitive strain 31 to bind more mercuric ions than strain 15. 12 references, 4 figures, 4 tables.

  19. Adipose tissue mitochondrial respiration and lipolysis before and after a weight loss by diet and RYGB

    DEFF Research Database (Denmark)

    Hansen, Merethe; Lund, Michael T.; Gregers, Emilie

    2015-01-01

    OBJECTIVE: To study adipose tissue mitochondrial respiration and lipolysis following a massive weight loss. METHODS: High resolution respirometry of adipose tissue biopsies and tracer determined whole body lipolysis. Sixteen obese patients with type 2 diabetes (T2DM) and 27 without (OB) were...... studied following a massive weight loss by diet and Roux-en-Y gastric bypass (RYGB). RESULTS: The mitochondrial respiratory rates were similar in OB and T2DM, and the mass-specific oxygen flux increased significantly 4 and 18 months post-surgery (P ... 2DM, visceral fat mass was always higher relative to the body fat mass (%) compared to OB. CONCLUSIONS: Adipose tissue mitochondrial respiratory capacity increases with RYGB. Adipocytes adapt to massive weight...

  20. Organic fuels for respiration in tropical river systems

    Science.gov (United States)

    Ward, N.; Keil, R. G.; Richey, J. E.; Krusche, A. V.; Medeiros, P. M.

    2011-12-01

    Watershed-derived organic matter is thought to provide anywhere from 30-90% of the organic matter in rivers (e.g. Hernes et al 2008; Spencer et al 2010). The most abundant biochemicals on land are cellulose, hemicelluloses, and lignin. Combined, they represent as much as 80% of the biomass in a typical forest and as much as 60% of the biomass in a typical field (natural or crop)(Bose et al 2009; Bridgeman et al., 2007; Hu and Zu 2006; Martens et al 2004). They are often assumed to be refractory and hard to degrade, but this assumption is at odds with virtually all observations: soils and marine sediments are not accumulating vast amounts of these compounds (Hedges and Oades, 1997), and degradation experiments suggest that cellulose, hemicelluloses and lignin are reactive and likely to be important fuels for respiration (Benner, 1991; Haddad et al, 1992; Dittmar et al, 2001; Otto and Simpson, 2006). During several trips to the lower Amazon River, incubation experiments were performed in which the biological degradation of lignin phenols was observed in order to assess the contribution of microbial respiration of terrestrially-derived macromolecules to gross respiration and CO2 gas evasion rates. Both particulate and dissolved lignin concentrations decreased by ~40% after being incubated in the dark for 5-7 days, indicating a turnover time of the entire lignin pool of 12-18 days. These results shift the paradigm that lignocellulose derived OM is highly recalcitrant, and indicate that microbial respiration of lignocellulose may play a larger role in total respiration rates/CO2 outgassing than previously thought. A simple mass balance calculation was done to test whether microbial degradation alone could explain the lignin data observed in the field. First, a theoretical particulate lignin concentration for Macapa was calculated based on the observed data at Obidos. The measured rate of particulate lignin degradation was multiplied by the transit time of water from

  1. Betaine is a positive regulator of mitochondrial respiration

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Icksoo, E-mail: icksoolee@dankook.ac.kr

    2015-01-09

    Highlights: • Betaine enhances cytochrome c oxidase activity and mitochondrial respiration. • Betaine increases mitochondrial membrane potential and cellular energy levels. • Betaine’s anti-tumorigenic effect might be due to a reversal of the Warburg effect. - Abstract: Betaine protects cells from environmental stress and serves as a methyl donor in several biochemical pathways. It reduces cardiovascular disease risk and protects liver cells from alcoholic liver damage and nonalcoholic steatohepatitis. Its pretreatment can rescue cells exposed to toxins such as rotenone, chloroform, and LiCl. Furthermore, it has been suggested that betaine can suppress cancer cell growth in vivo and in vitro. Mitochondrial electron transport chain (ETC) complexes generate the mitochondrial membrane potential, which is essential to produce cellular energy, ATP. Reduced mitochondrial respiration and energy status have been found in many human pathological conditions including aging, cancer, and neurodegenerative disease. In this study we investigated whether betaine directly targets mitochondria. We show that betaine treatment leads to an upregulation of mitochondrial respiration and cytochrome c oxidase activity in H2.35 cells, the proposed rate limiting enzyme of ETC in vivo. Following treatment, the mitochondrial membrane potential was increased and cellular energy levels were elevated. We propose that the anti-proliferative effects of betaine on cancer cells might be due to enhanced mitochondrial function contributing to a reversal of the Warburg effect.

  2. Cisplatin cytotoxicity is dependent on mitochondrial respiration in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Santhipriya Inapurapu

    2017-01-01

    Full Text Available Objective(s: To understand the role of mitochondrial respiration in cisplatin sensitivity, we have employed wild-type and mitochondrial DNA depleted Rho0 yeast cells. Materials and Methods: Wild type and Rho0 yeast cultured in fermentable and non-fermentable sugar containing media, were studied for their sensitivity against cisplatin by monitoring growth curves, oxygen consumption, pH changes in cytosol/mitochondrial compartments, reactive oxygen species production and respiratory control ratio. Results: Wild-type yeast grown on glycerol exhibited heightened sensitivity to cisplatin than yeast grown on glucose. Cisplatin (100 μM, although significantly reduced the growth of wild- type cells, only slightly altered the growth rate of Rho0 cells. Cisplatin treatment decreased both pHcyt and pHmit to a similar extent without affecting the pH difference. Cisplatin dose-dependently increased the oxidative stress in wild-type, but not in respiration-deficient Rho0 strain. Cisplatin decreased the respiratory control ratio. Conclusion: These results suggest that cisplatin toxicity is influenced by the respiratory capacity of the cells and the intracellular oxidative burden. Although cisplatin per se slightly decreased the respiration of yeast cells grown in glucose, it did not disturb the mitochondrial chemiosmotic gradient.

  3. A dynamic soil chamber system coupled with a tunable diode laser for online measurements of delta-13C, delta-18O, and efflux rate of soil respired CO2

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Heath H [Los Alamos National Laboratory; Mcdowell, Nate [Los Alamos National Laboratory; Hanson, David [UNM; Hunt, John [LANDCARE RESEARCH

    2009-01-01

    High frequency observations of the stable isotopic composition of CO(2) effluxes from soil have been sparse due in part to measurement challenges. We have developed an open-system method that utilizes a flow-through chamber coupled to a tunable diode laser (TDL) to quantify the rate of soil CO(2) efflux and its delta(13)C and delta(18)O values (delta(13)C(R) and delta(18)O(R), respectively). We tested the method first in the laboratory using an artificial soil test column and then in a semi-arid woodland. We found that the CO(2) efflux rates of 1.2 to 7.3 micromol m(-2) s(-1) measured by the chamber-TDL system were similar to measurements made using the chamber and an infrared gas analyzer (IRGA) (R(2) = 0.99) and compared well with efflux rates generated from the soil test column (R(2) = 0.94). Measured delta(13)C and delta(18)O values of CO(2) efflux using the chamber-TDL system at 2 min intervals were not significantly different from source air values across all efflux rates after accounting for diffusive enrichment. Field measurements during drought demonstrated a strong dependency of CO(2) efflux and isotopic composition on soil water content. Addition of water to the soil beneath the chamber resulted in average changes of +6.9 micromol m(-2) s(-1), -5.0 per thousand, and -55.0 per thousand for soil CO(2) efflux, delta(13)C(R) and delta(18)O(R), respectively. All three variables initiated responses within 2 min of water addition, with peak responses observed within 10 min for isotopes and 20 min for efflux. The observed delta(18)O(R) was more enriched than predicted from temperature-dependent H(2)O-CO(2) equilibration theory, similar to other recent observations of delta(18)O(R) from dry soils (Wingate L, Seibt U, Maseyk K, Ogee J, Almeida P, Yakir D, Pereira JS, Mencuccini M. Global Change Biol. 2008; 14: 2178). The soil chamber coupled with the TDL was found to be an effective method for capturing soil CO(2) efflux and its stable isotope composition at high

  4. Soil Respiration And Respiration Partitioning In An Oak-Savannah With A History Of Fertilization

    Science.gov (United States)

    Morris, K. A.; Nair, R.; Schrumpf, M.; Migliavacca, M.

    2017-12-01

    Soil respiration is a combination of autotrophic and heterotrophic components. These components have different controls and structurally complex ecosystems such as oak-savannahs offer an opportunity to study strongly contrasting conditions (ie., soil from under trees versus open areas) in an environment with similar soil mineralogy and climatic patterns. To measure respiration coming from plant roots, fungal hyphae, and free-living microbes we established stations of soil cores comprised of three selectively permeable meshes under tree canopies and in open grassy areas of a Holm Oak (Quercus ilex) savannah in Extremadura, Spain. Large plots of this ecosystem had previously been fertilized as part of a stoichiometeric imbalance study (in 2015). Stations were installed in Dec. 2016 within four plots; control, N added, P added, and N+P added. Respiration from cores was measured in campaigns at key phenological stages with a portable Li-Cor 8100A unit. Six months after installation > 50% of soil respiration was attributable to free-living microbes. There is a persistent effect of the prior fertilization, resulting in increased soil respiration in open areas regardless of fertilizer type, while respiration from under tree canopies had a varied response. Soil under tree canopies showed distinct sensitivity to stoichiometric imbalance, meaning that addition of N or P alone either did not change respiration or decreased it slightly, while N+P stimulated respiration. We determined that respiration from free-living microbes is a major component of soil respiration even in the most active plant growing season. However, because of the lag between the time of fertilization and the time of measurement, it not possible to say whether treatment responses are due solely to nutrient status of the soil or whether changes in plant biomass and species composition also play a role. Additional work planned at the site will shed light on this uncertainty as well as the contribution of

  5. [Research progress on photosynthesis regulating and controlling soil respiration].

    Science.gov (United States)

    Jing, Yan-Li; Guan, De-Xin; Wu, Jia-Bing; Wang, An-Zhi; Yuan, Feng-Hui

    2013-01-01

    To understand the mechanisms of soil respiration and accurately estimate its magnitude are the crucial basis of evaluating global carbon balance. However, the previously built soil respiration forecast models usually neglect the physiological processes that photosynthesis supplies substrates for rhizospheric respiration, leading to the defect in evaluating the mechanisms of soil respiration. This paper summarized the research progress on the mechanisms of photosynthetic regulation and control of soil respiration, introduced the related main research methods, and discussed the existing problems and research hotspots.

  6. [Effects of elevated temperature on soil organic carbon and soil respiration under subalpine coniferous forest in western Sichuan Province, China].

    Science.gov (United States)

    Pan, Xin-li; Lin, Bo; Liu, Qing

    2008-08-01

    To investigate the effects of elevated temperature on the soil organic carbon content, soil respiration rate, and soil enzyme activities in subalpine Picea asperata plantations in western Sichuan Province of China, a simulation study was conducted in situ with open-top chambers from November 2005 to July 2007. The results showed that under elevated temperature, the mean air temperature and soil temperature were 0.42 degrees C and 0.25 degrees C higher than the control, respectively. In the first and the second year, the increased temperature had somewhat decreasing effects on the soil organic carbon and the C/N ratio at the soil depths of 0-10 cm and 10-20 cm. In the first year the soil organic carbon and the C/N ratio in 0-10 cm soil layer decreased by 8.69%, and 8.52%, respectively; but in the second year, the decrements were lesser. Soil respiration rate was significantly enhanced in the first year of warming, but had no significant difference with the control in the second year. In the first year of warming, the activities of soil invertase, polyphenol oxidase, catalase, protease, and urease increased, and the invertase and polyphenol oxidase activities in 0-10 cm soil layer were significantly higher than the control. In the second year of warming, the activities of invertase, protease and urease still had an increase, but those of catalase and polyphenol oxidase had a downtrend, compared with the control.

  7. [Characteristics of Soil Respiration along Eroded Sloping Land with Different SOC Background on the Hilly Loess Plateau].

    Science.gov (United States)

    Chen, Gai; Xu, Ming-xiang; Zhang, Ya-feng; Wang, Chao-hua; Fan, Hui-min; Wang, Shan-shan

    2015-09-01

    This study aimed to characterize soil respiration along eroded sloping land at erosion and deposition area under different soil organic carbon(SOC) levels, and linked the relationship between soil respiration and soil temperature, soil moisture, SOC and slope position. Experiments were carried out in the plots of S type slopes include five different soil organic carbon levels in the Loess Hilly Region. The S type slopes were divided into control area at the top of the slope, erosion area at the middle of the slope and deposition area at the toe of the slope. We found that soil temperature had a greater impact on soil respiration in the deposition area, whereas soil moisture had a greater impact on soil respiration in the erosion area compared among control area, erosion area and deposition area. In addition, SOC was the most important factor affecting soil respiration, which can explain soil respiration variation 54. 72%, followed by soil moisture, slope position and soil temperature, which explain soil respiration variation 18. 86% , 16. 13% and 10. 29%, respectively. Soil respiration response to erosion showed obvious on-site and off-site effects along the eroded sloping land. Soil respiration in the erosion area was reduced by 21. 14% compared with control area, and soil respiration in the deposition area was increased by 21. 93% compared with control area. Erosion effect on source and sink of carbon emission was correlated with SOC content of the eroded sloping land. When SOC content was higher than 6. 82 g.kg-1, the slope. erosion tended to be a carbon sequestration process, and when SOC content was lower than 3.03 g.kg-1, the slope erosion tended to be a process of the carbon emission source. The model could reflect the relationship between soil respiration and independent variables of soil organic carbon content, soil temperature and moisture.

  8. Short Communication: HIV Patient Systemic Mitochondrial Respiration Improves with Exercise.

    Science.gov (United States)

    Kocher, Morgan; McDermott, Mindy; Lindsey, Rachel; Shikuma, Cecilia M; Gerschenson, Mariana; Chow, Dominic C; Kohorn, Lindsay B; Hetzler, Ronald K; Kimura, Iris F

    2017-10-01

    In HIV-infected individuals, impaired mitochondrial function may contribute to cardiometabolic disease as well as to fatigue and frailty. Aerobic exercise improves total body energy reserves; however, its impact at the cellular level is unknown. We assessed alterations in cellular bioenergetics in peripheral blood mononuclear cells (PBMC) before and after a 12-week aerobic exercise study in sedentary HIV-infected subjects on stable antiretroviral therapy who successfully completed a 12-week aerobic exercise program. In this prospective study, participants underwent supervised 20-40 min of light aerobic exercise (walking or jogging) performed three times per week for 12 weeks, gradually increasing to maintain an intensity of 50%-80% of heart rate reserve. Maximal aerobic capacity (VO 2MAX ) was assessed by a graded exercise test on a cycle ergometer before and after completion of the study. PBMC from compliant subjects (attended at least 70% of exercise sessions) were assessed for mitochondrial respiration using the Seahorse XF24 Bio-Analyzer. Seven of 24 enrolled subjects were compliant with the exercise regimen. In these individuals, a significant increase (p = .04) in VO 2MAX over 12 weeks was found with a median increase of 14%. During the same interval, a 2.45-fold increase in PBMC mitochondrial respiratory capacity (p = .04), a 5.65-fold increase in spare respiratory capacity (p = .01), and a 3.15-fold (p = .04) increase in nonmitochondrial respiration was observed. Aerobic exercise improves respiration at the cellular level. The diagnostic and prognostic value of such improved cellular respiration in the setting of chronic HIV warrants further investigation.

  9. Impacts of temperature on primary productivity and respiration in naturally structured macroalgal assemblages.

    Directory of Open Access Journals (Sweden)

    Leigh W Tait

    Full Text Available Rising global temperatures caused by human-mediated change has already triggered significant responses in organismal physiology, distribution and ecosystem functioning. Although the effects of rising temperature on the physiology of individual organisms are well understood, the effect on community-wide processes has remained elusive. The fixation of carbon via primary productivity is an essential ecosystem function and any shifts in the balance of primary productivity and respiration could alter the carbon balance of ecosystems. Here we show through a series of tests that respiration of naturally structured algal assemblages in southern New Zealand greatly increases with rising temperature, with implications for net primary productivity (NPP. The NPP of in situ macroalgal assemblages was minimally affected by natural temperature variation, possibly through photo-acclimation or temperature acclimation responses, but respiration rates and compensating irradiance were negatively affected. However, laboratory experiments testing the impacts of rising temperature on several photosynthetic parameters showed a decline in NPP, increasing respiration rates and increasing compensating irradiance. The respiration Q10 of laboratory assemblages (the difference in metabolic rates over 10°C averaged 2.9 compared to a Q10 of 2 often seen in other autotrophs. However, gross primary productivity (GPP Q10 averaged 2, indicating that respiration was more severely affected by rising temperature. Furthermore, combined high irradiance and high temperature caused photoinhibition in the laboratory, and resulted in 50% lower NPP at high irradiance. Our study shows that communities may be more severely affected by rising global temperatures than would be expected by responses of individual species. In particular, enhanced respiration rates and rising compensation points have the potential to greatly affect the carbon balance of macroalgal assemblages through declines in

  10. Plant Respiration and Climate Change Effects

    International Nuclear Information System (INIS)

    Bruhn, D.

    2002-04-01

    Plant respiration is one of the key processes in terms of an understanding of plant growth and functioning in a future climate. Short- and long-term effects of temperature and CO 2 on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO 2 from the level of individual respiratory enzymes, isolated mitochondria, whole-tissue, and up to the whole canopy level. The short-term effects of elevated atmospheric CO 2 on plant respiration appeared to be less than suggested so far in the literature. This was true both at the tissue level and for intact mitochondria. Respiratory enzymes can, however, be affected already at low CO 2 . These effects did not manifest itself at the tissue level, though, due to low degrees of control on the whole respiratory process exerted by the particular enzymes. Plant respiration on the other hand was affected by long-term growth at elevated atmospheric CO 2 . The findings of the reduced plant respiration at the leaf level were consistent with the literature and potential causes are discussed. Short-term effects of temperature on plant respiration were demonstrated to be dependent on the actual measurement temperature. Further, it is shown that mitochondrial leaf respiration in darkness and light differ substantially in the temperature sensitivity with the former being the far most sensitive. This has implications for modelling CO 2 exchange between vegetation and atmosphere as demonstrated here, since this has so far been neglected. Long-term effects of temperature resulted in respiratory acclimation in a number of species. Respiratory acclimation appeared not to occur to any one single type of growth temperature. The implications of this finding in combination with the timing of acclimation are discussed for modelling respiratory CO 2 release. (au)

  11. Plant Respiration and Climate Change Effects

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, D

    2002-04-01

    Plant respiration is one of the key processes in terms of an understanding of plant growth and functioning in a future climate. Short- and long-term effects of temperature and CO{sub 2} on plant respiration were investigated in a number of plant species. The experiments tested effects of either temperature and/or CO{sub 2} from the level of individual respiratory enzymes, isolated mitochondria, whole-tissue, and up to the whole canopy level. The short-term effects of elevated atmospheric CO{sub 2} on plant respiration appeared to be less than suggested so far in the literature. This was true both at the tissue level and for intact mitochondria. Respiratory enzymes can, however, be affected already at low CO{sub 2}. These effects did not manifest itself at the tissue level, though, due to low degrees of control on the whole respiratory process exerted by the particular enzymes. Plant respiration on the other hand was affected by long-term growth at elevated atmospheric CO{sub 2}. The findings of the reduced plant respiration at the leaf level were consistent with the literature and potential causes are discussed. Short-term effects of temperature on plant respiration were demonstrated to be dependent on the actual measurement temperature. Further, it is shown that mitochondrial leaf respiration in darkness and light differ substantially in the temperature sensitivity with the former being the far most sensitive. This has implications for modelling CO{sub 2} exchange between vegetation and atmosphere as demonstrated here, since this has so far been neglected. Long-term effects of temperature resulted in respiratory acclimation in a number of species. Respiratory acclimation appeared not to occur to any one single type of growth temperature. The implications of this finding in combination with the timing of acclimation are discussed for modelling respiratory CO{sub 2} release. (au)

  12. SU-E-J-67: Evaluation of Breathing Patterns for Respiratory-Gated Radiation Therapy Using Respiration Regularity Index

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, K; Lee, M; Kang, S; Yoon, J; Park, S; Hwang, T; Kim, H; Kim, K; Han, T; Bae, H [Hallym University College of Medicine, Anyang (Korea, Republic of)

    2014-06-01

    Purpose: Despite the importance of accurately estimating the respiration regularity of a patient in motion compensation treatment, an effective and simply applicable method has rarely been reported. The authors propose a simple respiration regularity index based on parameters derived from a correspondingly simplified respiration model. Methods: In order to simplify a patient's breathing pattern while preserving the data's intrinsic properties, we defined a respiration model as a power of cosine form with a baseline drift. According to this respiration formula, breathing-pattern fluctuation could be explained using four factors: sample standard deviation of respiration period, sample standard deviation of amplitude and the results of simple regression of the baseline drift (slope and standard deviation of residuals of a respiration signal. Overall irregularity (δ) was defined as a Euclidean norm of newly derived variable using principal component analysis (PCA) for the four fluctuation parameters. Finally, the proposed respiration regularity index was defined as ρ=ln(1+(1/ δ))/2, a higher ρ indicating a more regular breathing pattern. Subsequently, we applied it to simulated and clinical respiration signals from real-time position management (RPM; Varian Medical Systems, Palo Alto, CA) and investigated respiration regularity. Moreover, correlations between the regularity of the first session and the remaining fractions were investigated using Pearson's correlation coefficient. Results: The respiration regularity was determined based on ρ; patients with ρ<0.3 showed worse regularity than the others, whereas ρ>0.7 was suitable for respiratory-gated radiation therapy (RGRT). Fluctuations in breathing cycle and amplitude were especially determinative of ρ. If the respiration regularity of a patient's first session was known, it could be estimated through subsequent sessions. Conclusions: Respiration regularity could be objectively determined

  13. Controls on winter ecosystem respiration in temperate and boreal ecosystems

    Directory of Open Access Journals (Sweden)

    T. Wang

    2011-07-01

    Full Text Available Winter CO2 fluxes represent an important component of the annual carbon budget in northern ecosystems. Understanding winter respiration processes and their responses to climate change is also central to our ability to assess terrestrial carbon cycle and climate feedbacks in the future. However, the factors influencing the spatial and temporal patterns of winter ecosystem respiration (Reco of northern ecosystems are poorly understood. For this reason, we analyzed eddy covariance flux data from 57 ecosystem sites ranging from ~35° N to ~70° N. Deciduous forests were characterized by the highest winter Reco rates (0.90 ± 0.39 g C m−2 d−1, when winter is defined as the period during which daily air temperature remains below 0 °C. By contrast, arctic wetlands had the lowest winter Reco rates (0.02 ± 0.02 g C m−2 d−1. Mixed forests, evergreen needle-leaved forests, grasslands, croplands and boreal wetlands were characterized by intermediate winter Reco rates (g C m−2 d−1 of 0.70(±0.33, 0.60(±0.38, 0.62(±0.43, 0.49(±0.22 and 0.27(±0.08, respectively. Our cross site analysis showed that winter air (Tair and soil (Tsoil temperature played a dominating role in determining the spatial patterns of winter Reco in both forest and managed ecosystems (grasslands and croplands. Besides temperature, the seasonal amplitude of the leaf area index (LAI, inferred from satellite observation, or growing season gross primary productivity, which we use here as a proxy for the amount of recent carbon available for Reco in the subsequent winter, played a marginal role in winter CO2 emissions from forest ecosystems. We found that winter Reco sensitivity to temperature variation across space (

  14. Endometrial Scratch Injury Induces Higher Pregnancy Rate for Women With Unexplained Infertility Undergoing IUI With Ovarian Stimulation: A Randomized Controlled Trial.

    Science.gov (United States)

    Maged, Ahmed M; Al-Inany, Hesham; Salama, Khaled M; Souidan, Ibrahim I; Abo Ragab, Hesham M; Elnassery, Noura

    2016-02-01

    To explore the impact of endometrial scratch injury (ESI) on intrauterine insemination (IUI) success. One hundred and fifty four infertile women received 100 mg of oral clomiphene citrate for 5 days starting on day 3 of the menstrual cycle. Patients were randomized to 2 equal groups: Group C received IUI without ESI and group S had ESI. Successful pregnancy was confirmed by ultrasound. 13, 21, and 10 women got pregnant after the first, second, and third IUI trials, respectively, with 28.6% cumulative pregnancy rate (PR). The cumulative PR was significantly higher in group S (39%) compared to group C (18.2%). The PR in group S was significantly higher compared to that in group C at the second and third trials. The PR was significantly higher in group S at the second trial compared to that reported in the same group at the first trial but nonsignificantly higher compared to that reported during the third trial, while in group C, the difference was nonsignificant. Eight pregnant women had first trimester abortion with 18.2% total abortion rate with nonsignificant difference between studied groups. The ESI significantly improves the outcome of IUI in women with unexplained infertility especially when conducted 1 month prior to IUI. © The Author(s) 2015.

  15. Microbial Community Response of an Organohalide Respiring Enrichment Culture to Permanganate Oxidation.

    Science.gov (United States)

    Sutton, Nora B; Atashgahi, Siavash; Saccenti, Edoardo; Grotenhuis, Tim; Smidt, Hauke; Rijnaarts, Huub H M

    2015-01-01

    While in situ chemical oxidation is often used to remediate tetrachloroethene (PCE) contaminated locations, very little is known about its influence on microbial composition and organohalide respiration (OHR) activity. Here, we investigate the impact of oxidation with permanganate on OHR rates, the abundance of organohalide respiring bacteria (OHRB) and reductive dehalogenase (rdh) genes using quantitative PCR, and microbial community composition through sequencing of 16S rRNA genes. A PCE degrading enrichment was repeatedly treated with low (25 μmol), medium (50 μmol), or high (100 μmol) permanganate doses, or no oxidant treatment (biotic control). Low and medium treatments led to higher OHR rates and enrichment of several OHRB and rdh genes, as compared to the biotic control. Improved degradation rates can be attributed to enrichment of (1) OHRB able to also utilize Mn oxides as a terminal electron acceptor and (2) non-dechlorinating community members of the Clostridiales and Deltaproteobacteria possibly supporting OHRB by providing essential co-factors. In contrast, high permanganate treatment disrupted dechlorination beyond cis-dichloroethene and caused at least a 2-4 orders of magnitude reduction in the abundance of all measured OHRB and rdh genes, as compared to the biotic control. High permanganate treatments resulted in a notably divergent microbial community, with increased abundances of organisms affiliated with Campylobacterales and Oceanospirillales capable of dissimilatory Mn reduction, and decreased abundance of presumed supporters of OHRB. Although OTUs classified within the OHR-supportive order Clostridiales and OHRB increased in abundance over the course of 213 days following the final 100 μmol permanganate treatment, only limited regeneration of PCE dechlorination was observed in one of three microcosms, suggesting strong chemical oxidation treatments can irreversibly disrupt OHR. Overall, this detailed investigation into dose

  16. Oxygen dependence of respiration in rat spinotrapezius muscle in situ

    Science.gov (United States)

    Pittman, Roland N.

    2012-01-01

    The oxygen dependence of respiration in striated muscle in situ was studied by measuring the rate of decrease of interstitial Po2 [oxygen disappearance curve (ODC)] following rapid arrest of blood flow by pneumatic tissue compression, which ejected red blood cells from the muscle vessels and made the ODC independent from oxygen bound to hemoglobin. After the contribution of photo-consumption of oxygen by the method was evaluated and accounted for, the corrected ODCs were converted into the Po2 dependence of oxygen consumption, V̇o2, proportional to the rate of Po2 decrease. Fitting equations obtained from a model of heterogeneous intracellular Po2 were applied to recover the parameters describing respiration in muscle fibers, with a predicted sigmoidal shape for the dependence of V̇o2 on Po2. This curve consists of two regions connected by the point for critical Po2 of the cell (i.e., Po2 at the sarcolemma when the center of the cell becomes anoxic). The critical Po2 was below the Po2 for half-maximal respiratory rate (P50) for the cells. In six muscles at rest, the rate of oxygen consumption was 139 ± 6 nl O2/cm3·s and mitochondrial P50 was k = 10.5 ± 0.8 mmHg. The range of Po2 values inside the muscle fibers was found to be 4–5 mmHg at the critical Po2. The oxygen dependence of respiration can be studied in thin muscles under different experimental conditions. In resting muscle, the critical Po2 was substantially lower than the interstitial Po2 of 53 ± 2 mmHg, a finding that indicates that V̇o2 under this circumstance is independent of oxygen supply and is discordant with the conventional hypothesis of metabolic regulation of the oxygen supply to tissue. PMID:22523254

  17. [The significance of sympathovagal balance in the forming of respiration-dependent oscillations in cardiovascular system in human].

    Science.gov (United States)

    Krasnikov, G V; Tiurina, M Ĭ; Tankanag, A V; Piskunova, G M; Cheremis, N K

    2014-01-01

    The effect of deep breathing controlled in both rate and amplitude on the heart rate variability (HRV) and respiration-dependent blood flow oscillations of forearm and finger-pad skin has been studied in 29 young healthy volunteers from 18 to 25 years old. To reveal the effect of the segments of the vegetative autonomic nervous system on the amplitudes of HRV and respiration-dependent oscillations of skin blood flow we estimated the parameters of the cardiovascular system into two groups of participants: with formally high and low sympathovagal balance values. The sympathovagal balance value was judged by the magnitude of LF/HF power ratio calculated for each participant using the spontaneous breathing rhythmogram. It was found what the participants with predominant parasympathetic tonus had statistically significant higher amplitudes of H R V and skin blood flow oscillations in the breathing rate less than 4 cycles per min than the subjects with predominant sympathetic tonus. In the forearm skin, where the density of sympathetic innervations is low comparatively to that in the finger skin, no statistically significant differences in the amplitude of respiratory skin blood flow oscillations was found between the two groups of participants.

  18. Soil respiration and organic carbon dynamics with grassland conversions to woodlands in temperate china.

    Directory of Open Access Journals (Sweden)

    Wei Wang

    Full Text Available Soils are the largest terrestrial carbon store and soil respiration is the second-largest flux in ecosystem carbon cycling. Across China's temperate region, climatic changes and human activities have frequently caused the transformation of grasslands to woodlands. However, the effect of this transition on soil respiration and soil organic carbon (SOC dynamics remains uncertain in this area. In this study, we measured in situ soil respiration and SOC storage over a two-year period (Jan. 2007-Dec. 2008 from five characteristic vegetation types in a forest-steppe ecotone of temperate China, including grassland (GR, shrubland (SH, as well as in evergreen coniferous (EC, deciduous coniferous (DC and deciduous broadleaved forest (DB, to evaluate the changes of soil respiration and SOC storage with grassland conversions to diverse types of woodlands. Annual soil respiration increased by 3%, 6%, 14%, and 22% after the conversion from GR to EC, SH, DC, and DB, respectively. The variation in soil respiration among different vegetation types could be well explained by SOC and soil total nitrogen content. Despite higher soil respiration in woodlands, SOC storage and residence time increased in the upper 20 cm of soil. Our results suggest that the differences in soil environmental conditions, especially soil substrate availability, influenced the level of annual soil respiration produced by different vegetation types. Moreover, shifts from grassland to woody plant dominance resulted in increased SOC storage. Given the widespread increase in woody plant abundance caused by climate change and large-scale afforestation programs, the soils are expected to accumulate and store increased amounts of organic carbon in temperate areas of China.

  19. Plankton community respiration, net ecosystem metabolism, and oxygen dynamics on the Louisiana continental shelf: implications for hypoxia

    Science.gov (United States)

    We conducted a multi-year study of the Louisiana continental shelf (LCS) to better understand the linkages between water column metabolism and the formation of hypoxia (dissolved oxygen respiration rates (WR) were measured on 10 cr...

  20. Annual ecosystem respiration variability of alpine peatland on the eastern Qinghai-Tibet Plateau and its controlling factors.

    Science.gov (United States)

    Peng, Haijun; Hong, Bing; Hong, Yetang; Zhu, Yongxuan; Cai, Chen; Yuan, Lingui; Wang, Yu

    2015-09-01

    Peatlands are widely developed in the eastern Qinghai-Tibet Plateau, but little is known about carbon budgets for these alpine peatland ecosystems. In this study, we used an automatic chamber system to measure ecosystem respiration in the Hongyuan peatland, which is located in the eastern Qinghai-Tibet Plateau. Annual ecosystem respiration measurements showed a typical seasonal pattern, with the peak appearing in June. The highest respiration was 10.43 μmol CO2/m(2)/s, and the lowest was 0.20 μmol CO2/m(2)/s. The annual average ecosystem respiration was 2.06 μmol CO2/m(2)/s. The total annual respiration was 599.98 g C/m(2), and respiration during the growing season (from May to September) accounted for 78 % of the annual sum. Nonlinear regression revealed that ecosystem respiration has a significant exponential correlation with soil temperature at 10-cm depth (R (2) = 0.98). The Q 10 value was 3.90, which is far higher than the average Q 10 value of terrestrial ecosystems. Ecosystem respiration had an apparent diurnal variation pattern in growing season, with peaks and valleys appearing at approximately 14:00 and 10:00, respectively, which could be explained by soil temperature and soil water content variation at 10-cm depth.

  1. Being born under adverse economic conditions leads to a higher cardiovascular mortality rate later in life: evidence based on individuals born at different stages of the business cycle.

    Science.gov (United States)

    van den Berg, Gerard J; Doblhammer-Reiter, Gabriele; Christensen, Kaare

    2011-05-01

    We connect the recent medical and economic literatures on the long-run effects of early-life conditions by analyzing the effects of economic conditions on the individual cardiovascular (CV) mortality rate later in life, using individual data records from the Danish Twin Registry covering births since the 1870s and including the cause of death. To capture exogenous variation of conditions early in life, we use the state of the business cycle around birth. We find significant negative effects of economic conditions around birth on the individual CV mortality rate at higher ages. There is no effect on the cancer-specific mortality rate. From variation within and between monozygotic and dizygotic twin pairs born under different conditions, we conclude that the fate of an individual is more strongly determined by genetic and household-environmental factors if early-life conditions are poor. Individual-specific qualities come more to fruition if the starting position in life is better.

  2. Flexible Coupling of Respiration and Vocalizations with Locomotion and Head Movements in the Freely Behaving Rat

    Directory of Open Access Journals (Sweden)

    Joseph Andrews Alves

    2016-01-01

    Full Text Available Quadrupedal mammals typically synchronize their respiration with body movements during rhythmic locomotion. In the rat, fast respiration is coupled to head movements during sniffing behavior, but whether respiration is entrained by stride dynamics is not known. We recorded intranasal pressure, head acceleration, instantaneous speed, and ultrasonic vocalizations from male and female adult rats while freely behaving in a social environment. We used high-speed video recordings of stride to understand how head acceleration signals relate to locomotion and developed techniques to identify episodes of sniffing, walking, trotting, and galloping from the recorded variables. Quantitative analysis of synchrony between respiration and head acceleration rhythms revealed that respiration and locomotion movements were coordinated but with a weaker coupling than expected from previous work in other mammals. We have recently shown that rats behaving in social settings produce high rates of ultrasonic vocalizations during locomotion bouts. Accordingly, rats emitted vocalizations in over half of the respiratory cycles during fast displacements. We present evidence suggesting that emission of these calls disrupts the entrainment of respiration by stride. The coupling between these two variables is thus flexible, such that it can be overridden by other behavioral demands.

  3. Temperature dependence of bulk respiration of crop stands. Measurement and model fitting

    International Nuclear Information System (INIS)

    Tani, Takashi; Arai, Ryuji; Tako, Yasuhiro

    2007-01-01

    The objective of the present study was to examine whether the temperature dependence of respiration at a crop-stand scale could be directly represented by an Arrhenius function that was widely used for representing the temperature dependence of leaf respiration. We determined temperature dependences of bulk respiration of monospecific stands of rice and soybean within a range of the air temperature from 15 to 30degC using large closed chambers. Measured responses of respiration rates of the two stands were well fitted by the Arrhenius function (R 2 =0.99). In the existing model to assess the local radiological impact of the anthropogenic carbon-14, effects of the physical environmental factors on photosynthesis and respiration of crop stands are not taken into account for the calculation of the net amount of carbon per cultivation area in crops at harvest which is the crucial parameter for the estimation of the activity concentration of carbon-14 in crops. Our result indicates that the Arrhenius function is useful for incorporating the effect of the temperature on respiration of crop stands into the model which is expected to contribute to a more realistic estimate of the activity concentration of carbon-14 in crops. (author)

  4. Ecosystem warming does not affect photosynthesis or aboveground autotrophic respiration for boreal black spruce

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, D.R. [Wyoming Univ., Laramie, WY (United States). Dept. of Renewable Resources; Gower, S.T. [Wisconsin Univ., Madison, WI (United States). Dept. of Forest Ecology and Management

    2010-04-15

    Substantial increases in climatic temperatures may cause boreal forests to become a carbon source. An improved understanding of the effect of climatic warming on photosynthesis and autotrophic respiration is needed in order to determine the impact of temperature increases on net carbon balances. This study measured the light-saturated photosynthesis foliage respiration and stem respiration of black spruce in heated and control plots during a 3-year period at a site located in Thompson, Manitoba. Greenhouses and soil-heating cables were used to maintain air and soil temperatures at 5 degrees C above ambient air and soil temperatures. Studies were conducted to determine the influence of soil and air warming; soil-only warming; and greenhouses maintained at ambient temperatures. The study showed that treatment differences for photosynthesis, foliage respiration, and stem respiration were not significant over the 3-year period. Results suggested that black spruce may not have significant changes in photosynthesis or respiration rates in warmer climates. 38 refs., 3 tabs., 4 figs.

  5. Cheyne-Stokes respiration in patients with congestive heart failure: causes and consequences.

    Science.gov (United States)

    Lorenzi-Filho, Geraldo; Genta, Pedro R; Figueiredo, Adelaide C; Inoue, Daniel

    2005-08-01

    Cheyne-Stokes respiration is a form of periodic breathing in which central apneas and hypopneas alternate with periods of hyperventilation, producing a waxing and waning pattern of tidal volume. This review focuses on the causes and consequences of Cheyne-Stokes respiration in patients with congestive heart failure, in whom the prevalence is strikingly high and ranges from 30% to 50%. Several factors have been implicated in the genesis of Cheyne-Stokes respiration, including low cardiac output and recurrent hypoxia. The key pathophysiological mechanism triggering Cheyne-Stokes respiration is hyperventilation and low arterial CO2 (PaCO2) that when below the apneic threshold triggers a central apnea. Hyperventilation is associated with pulmonary congestion, and Cheyne-Stokes respiration is more prone to occur during sleep, when the respiratory system is mainly dependent on chemical control. It is associated with recurrent dips in oxygen saturation and arousals from sleep, with oscillations in blood pressure and heart rate, sympathetic activation and increased risk of ventricular tachycardia. Cheyne-Stokes respiration is an independent marker of poor prognosis and may participate in a vicious cycle, further stressing the failing heart.

  6. Olfactory Bulb Field Potentials and Respiration in Sleep-Wake States of Mice.

    Science.gov (United States)

    Jessberger, Jakob; Zhong, Weiwei; Brankačk, Jurij; Draguhn, Andreas

    2016-01-01

    It is well established that local field potentials (LFP) in the rodent olfactory bulb (OB) follow respiration. This respiration-related rhythm (RR) in OB depends on nasal air flow, indicating that it is conveyed by sensory inputs from the nasal epithelium. Recently RR was found outside the olfactory system, suggesting that it plays a role in organizing distributed network activity. It is therefore important to measure RR and to delineate it from endogenous electrical rhythms like theta which cover similar frequency bands in small rodents. In order to validate such measurements in freely behaving mice, we compared rhythmic LFP in the OB with two respiration-related biophysical parameters: whole-body plethysmography (PG) and nasal temperature (thermocouple; TC). During waking, all three signals reflected respiration with similar reliability. Peak power of RR in OB decreased with increasing respiration rate whereas power of PG increased. During NREM sleep, respiration-related TC signals disappeared and large amplitude slow waves frequently concealed RR in OB. In this situation, PG provided a reliable signal while breathing-related rhythms in TC and OB returned only during microarousals. In summary, local field potentials in the olfactory bulb do reliably reflect respiratory rhythm during wakefulness and REM sleep but not during NREM sleep.

  7. Olfactory Bulb Field Potentials and Respiration in Sleep-Wake States of Mice

    Directory of Open Access Journals (Sweden)

    Jakob Jessberger

    2016-01-01

    Full Text Available It is well established that local field potentials (LFP in the rodent olfactory bulb (OB follow respiration. This respiration-related rhythm (RR in OB depends on nasal air flow, indicating that it is conveyed by sensory inputs from the nasal epithelium. Recently RR was found outside the olfactory system, suggesting that it plays a role in organizing distributed network activity. It is therefore important to measure RR and to delineate it from endogenous electrical rhythms like theta which cover similar frequency bands in small rodents. In order to validate such measurements in freely behaving mice, we compared rhythmic LFP in the OB with two respiration-related biophysical parameters: whole-body plethysmography (PG and nasal temperature (thermocouple; TC. During waking, all three signals reflected respiration with similar reliability. Peak power of RR in OB decreased with increasing respiration rate whereas power of PG increased. During NREM sleep, respiration-related TC signals disappeared and large amplitude slow waves frequently concealed RR in OB. In this situation, PG provided a reliable signal while breathing-related rhythms in TC and OB returned only during microarousals. In summary, local field potentials in the olfactory bulb do reliably reflect respiratory rhythm during wakefulness and REM sleep but not during NREM sleep.

  8. Effect of typhoon disturbance on soil respiration dynamic in a tropical broadleaves plantation in southern Taiwan

    Science.gov (United States)

    Chiang, Po-Neng; Yu, Jui-Chu; Lai, Yen-Jen

    2017-04-01

    Global forests contain 69% of total carbon stored in forest soil and litter. But the carbon storage ability and release rate of warming gases of forest soil also affect global climate change. Reforestation is one of the best solutions to mitigate warming gases release and to store in soil. Typhoon is one of the most hazards to disturb forest ecosystem and change carbon cycle. Typhoon disturbance is also affect soil carbon cycle such as soil respiration, carbon storage. Therefore, the objective of this study is to clarify the effect of typhoon disturbance on soil respiration dynamic in a tropical broadleaves plantation in southern Taiwan. Fourteen broadleaved tree species were planted in 2002-2005. Twelves continuous soil respiration chambers was divided two treatments (trench and non-trench) and observed since 2011 to 2014. The soil belongs to Entisol with over 60% of sandstone. The soil pH is 5.5 with low base cations because of high sand percentage. Forest biometric such as tree high, DBH, litterfall was measured in 2011-2014. Data showed that the accumulation amount of litterfall was highest in December to February and lowest in June. Soil respiration was related with season variation in research site. Soil temperature showed significantly exponential related with soil respiration in research site (p<0.001).However, soil respiration showed significantly negative relationship with total amount of litterfall (p<0.001), suggesting that the tree was still young and did not reach crown closure.

  9. Higher Prevalence and Awareness, but Lower Control Rate of Hypertension in Patients with Diabetes than General Population: The Fifth Korean National Health and Nutrition Examination Survey in 2011

    Directory of Open Access Journals (Sweden)

    Seung-Hyun Ko

    2014-02-01

    Full Text Available BackgroundWe investigated the prevalence, awareness, treatment, and control rate of hypertension in Korean adults with diabetes using nationally representative data.MethodsUsing data of 5,105 adults from the fifth Korea National Health and Nutrition Examination Survey in 2011 (4,389 nondiabetes mellitus [non-DM], 242 newly diagnosed with DM (new-DM, and 474 previously diagnosed with DM (known-DM, we analyzed the prevalence of hypertension (mean systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or use of antihypertensive medication and control rate of hypertension (blood pressure [BP] <130/80 mm Hg.ResultsThe prevalence of hypertension in diabetic adults was 54.6% (44.4% in new-DM and 62.6% in known-DM, P<0.0001 and P<0.0001, respectively compared with non-DM adults (26.2%. Compared to non-DM, awareness (85.7%, P<0.001 and treatment (97.0%, P=0.020 rates were higher in known-DM, whereas no differences were found between new-DM and non-DM. Control rate among all hypertensive subjects was lower in new-DM (14.9%, compared to non-DM (35.1%, P<0.001 and known-DM (33.3%, P=0.004. Control rate among treated subjects was also lower in new-DM (25.2%, compared to non-DM (68.4%, P<0.0001 and known-DM (39.9%, P<0.0001.ConclusionHigher prevalence and low control rate of hypertension in adults with diabetes suggest that stringent efforts are needed to control BP in patients with diabetes, particularly in newly diagnosed diabetic patients.

  10. Higher success rate with transcranial electrical stimulation of motor-evoked potentials using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery.

    Science.gov (United States)

    Shigematsu, Hideki; Kawaguchi, Masahiko; Hayashi, Hironobu; Takatani, Tsunenori; Iwata, Eiichiro; Tanaka, Masato; Okuda, Akinori; Morimoto, Yasuhiko; Masuda, Keisuke; Tanaka, Yuu; Tanaka, Yasuhito

    2017-10-01

    During spine surgery, the spinal cord is electrophysiologically monitored via transcranial electrical stimulation of motor-evoked potentials (TES-MEPs) to prevent injury. Transcranial electrical stimulation of motor-evoked potential involves the use of either constant-current or constant-voltage stimulation; however, there are few comparative data available regarding their ability to adequately elicit compound motor action potentials. We hypothesized that the success rates of TES-MEP recordings would be similar between constant-current and constant-voltage stimulations in patients undergoing spine surgery. The objective of this study was to compare the success rates of TES-MEP recordings between constant-current and constant-voltage stimulation. This is a prospective, within-subject study. Data from 100 patients undergoing spinal surgery at the cervical, thoracic, or lumbar level were analyzed. The success rates of the TES-MEP recordings from each muscle were examined. Transcranial electrical stimulation with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions (international "10-20" system) was applied to each patient. Compound muscle action potentials were bilaterally recorded from the abductor pollicis brevis (APB), deltoid (Del), abductor hallucis (AH), tibialis anterior (TA), gastrocnemius (GC), and quadriceps (Quad) muscles. The success rates of the TES-MEP recordings from the right Del, right APB, bilateral Quad, right TA, right GC, and bilateral AH muscles were significantly higher using constant-voltage stimulation than those using constant-current stimulation. The overall success rates with constant-voltage and constant-current stimulations were 86.3% and 68.8%, respectively (risk ratio 1.25 [95% confidence interval: 1.20-1.31]). The success rates of TES-MEP recordings were higher using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery. Copyright © 2017

  11. MICROBIAL COLONIZATION, RESPIRATION, AND BREAKDOWN OF MAPLE LEAVES ALONG A STREAM-MARSH CONTINUUM

    Science.gov (United States)

    Breakdown rates, macroinvertebrate and bacterial colonization, and microbial respiration were measured on decaying maple (Acer saccharum) leaves at three sites along a stream-marsh continuum. Breakdown rates (-k+-SE) were 0.0284+-0.0045 d-1 for leaves in a high-gradient, non-tida...

  12. Improving the ablation efficiency of excimer laser systems with higher repetition rates through enhanced debris removal and optimized spot pattern.

    Science.gov (United States)

    Arba-Mosquera, Samuel; Klinner, Thomas

    2014-03-01

    To evaluate the reasons for the required increased radiant exposure for higher-repetition-rate excimer lasers and determine experimentally possible compensations to achieve equivalent ablation profiles maintaining the same single-pulse energies and radiant exposures for laser repetition rates ranging from 430 to 1000 Hz. Schwind eye-tech-solutions GmbH and Co. KG, Kleinostheim, Germany. Experimental study. Poly(methyl methacrylate) (PMMA) plates were photoablated. The pulse laser energy was maintained during all experiments; the effects of the flow of the debris removal, the shot pattern for the correction, and precooling the PMMA plates were evaluated in terms of achieved ablation versus repetition rate. The mean ablation performance ranged from 88% to 100%; the variability between the profile measurements ranged from 1.4% to 6.2%. Increasing the laser repetition rate from 430 Hz to 1000 Hz reduced the mean ablation performance from 98% to 91% and worsened the variability from 1.9% to 4.3%. Increasing the flow of the debris removal, precooling the PMMA plates to -18°C, and adapting the shot pattern for the thermal response of PMMA to excimer ablation helped stabilize the variability. Only adapting the shot pattern for the thermal response of PMMA to excimer ablation helped stabilize the mean ablation performance. The ablation performance of higher-repetition-rate excimer lasers on PMMA improved with improvements in the debris removal systems and shot pattern. More powerful debris removal systems and smart shot patterns in terms of thermal response improved the performance of these excimer lasers. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  13. Effects of season on the bathypelagic mysid Gnathophausia ingens: water content, respiration, and excretion

    Science.gov (United States)

    Hiller-Adams, Page; Childress, James J.

    1983-06-01

    Water contents, oxygen consumption rates and ammonia excretion rates of individuals of the large bathypelagic mysid Gnathophausia ingens were measured as a function of size and season (winter and summer). Individuals of the sizes studied live permanently beneath the euphotic zone. Water content, as a percent of wet weight, is higher in winter than in summer, suggesting seasonal variability in the midwater environment. Our data suggest that the seasonal change in water content increases with increasing size. We suggest that the changes are due in part to seasonal changes in food intake. Seasonal differences were not observed in wet-weight-specific rates of either respiration or ammonia excretion. Both rates decrease with increasing size. The constancy of the atomic O:N ratio and its high value (geometric mean = 44.3) indicate that the average proportions of lipid and protein metabolized by individuals were independent of size and season and that lipid stores were not sufficiently depleted, even in small animals, to cause a shift to predominantly protein metabolism in winter or summer. On the average, metabolic rates of individuals were unaffected by seasonal variation in the midwater environment.

  14. Older Adults With a Combination of Vision and Hearing Impairment Experience Higher Rates of Cognitive Impairment, Functional Dependence, and Worse Outcomes Across a Set of Quality Indicators.

    Science.gov (United States)

    Davidson, Jacob G S; Guthrie, Dawn M

    2017-08-01

    Hearing and vision impairment were examined across several health-related outcomes and across a set of quality indicators (QIs) in home care clients with both vision and hearing loss (or dual sensory impairment [DSI]). Data collected using the Resident Assessment Instrument for Home Care (RAI-HC) were analyzed in a sample of older home care clients. The QIs represent the proportion of clients experiencing negative outcomes (e.g., falls, social isolation). The average age of clients was 82.8 years ( SD = 7.9), 20.5% had DSI and 8.5% had a diagnosis of Alzheimer's disease (AD). Clients with DSI were more likely to have a diagnosis of dementia (not AD), have functional impairments, report loneliness, and have higher rates across 20 of the 22 QIs, including communication difficulty and cognitive decline. Clients with highly impaired hearing, and any visual impairment, had the highest QI rates. Individuals with DSI experience higher rates of adverse events across many health-related outcomes and QIs. Understanding the unique contribution of hearing and vision in this group can promote optimal quality of care.

  15. Penetration of Combustion Aerosol Particles Through Filters of NIOSH-Certified Filtering Facepiece Respirators (FFRs).

    Science.gov (United States)

    Gao, Shuang; Kim, Jinyong; Yermakov, Michael; Elmashae, Yousef; He, Xinjian; Reponen, Tiina; Grinshpun, Sergey A

    2015-01-01

    Filtering facepiece respirators (FFRs) are commonly worn by first responders, first receivers, and other exposed groups to protect against exposure to airborne particles, including those originated by combustion. Most of these FFRs are NIOSH-certified (e.g., N95-type) based on the performance testing of their filters against charge-equilibrated aerosol challenges, e.g., NaCl. However, it has not been examined if the filtration data obtained with the NaCl-challenged FFR filters adequately represent the protection against real aerosol hazards such as combustion particles. A filter sample of N95 FFR mounted on a specially designed holder was challenged with NaCl particles and three combustion aerosols generated in a test chamber by burning wood, paper, and plastic. The concentrations upstream (Cup) and downstream (Cdown) of the filter were measured with a TSI P-Trak condensation particle counter and a Grimm Nanocheck particle spectrometer. Penetration was determined as (Cdown/Cup) ×100%. Four test conditions were chosen to represent inhalation flows of 15, 30, 55, and 85 L/min. Results showed that the penetration values of combustion particles were significantly higher than those of the "model" NaCl particles (p combustion particles. Aerosol type, inhalation flow rate and particle size were significant (p combustion particles through R95 and P95 FFR filters (were tested in addition to N95) were not significantly higher than that obtained with NaCl particles. The findings were attributed to several effects, including the degradation of an N95 filter due to hydrophobic organic components generated into the air by combustion. Their interaction with fibers is anticipated to be similar to those involving "oily" particles. The findings of this study suggest that the efficiency of N95 respirator filters obtained with the NaCl aerosol challenge may not accurately predict (and rather overestimate) the filter efficiency against combustion particles.

  16. Central nervous system tumours among adolescents and young adults (15-39 years) in Southern and Eastern Europe: Registration improvements reveal higher incidence rates compared to the US.

    Science.gov (United States)

    Georgakis, Marios K; Panagopoulou, Paraskevi; Papathoma, Paraskevi; Tragiannidis, Athanasios; Ryzhov, Anton; Zivkovic-Perisic, Snezana; Eser, Sultan; Taraszkiewicz, Łukasz; Sekerija, Mario; Žagar, Tina; Antunes, Luis; Zborovskaya, Anna; Bastos, Joana; Florea, Margareta; Coza, Daniela; Demetriou, Anna; Agius, Domenic; Strahinja, Rajko M; Sfakianos, Georgios; Nikas, Ioannis; Kosmidis, Sofia; Razis, Evangelia; Pourtsidis, Apostolos; Kantzanou, Maria; Dessypris, Nick; Petridou, Eleni Th

    2017-11-01

    To present incidence of central nervous system (CNS) tumours among adolescents and young adults (AYAs; 15-39 years) derived from registries of Southern and Eastern Europe (SEE) in comparison to the Surveillance, Epidemiology and End Results (SEER), US and explore changes due to etiological parameters or registration improvement via evaluating time trends. Diagnoses of 11,438 incident malignant CNS tumours in AYAs (1990-2014) were retrieved from 14 collaborating SEE cancer registries and 13,573 from the publicly available SEER database (1990-2012). Age-adjusted incidence rates (AIRs) were calculated; Poisson and joinpoint regression analyses were performed for temporal trends. The overall AIR of malignant CNS tumours among AYAs was higher in SEE (28.1/million) compared to SEER (24.7/million). Astrocytomas comprised almost half of the cases in both regions, albeit the higher proportion of unspecified cases in SEE registries (30% versus 2.5% in SEER). Similar were the age and gender distributions across SEE and SEER with a male-to-female ratio of 1.3 and an overall increase of incidence by age. Increasing temporal trends in incidence were documented in four SEE registries (Greater Poland, Portugal North, Turkey-Izmir and Ukraine) versus an annual decrease in Croatia (-2.5%) and a rather stable rate in SEER (-0.3%). This first report on descriptive epidemiology of AYAs malignant CNS tumours in the SEE area shows higher incidence rates as compared to the United States of America and variable temporal trends that may be linked to registration improvements. Hence, it emphasises the need for optimisation of cancer registration processes, as to enable the in-depth evaluation of the observed patterns by disease subtype. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Melanogenesis inhibits respiration in B16-F10 melanoma cells whereas enhances mitochondrial cell content

    International Nuclear Information System (INIS)

    Meira, Willian Vanderlei; Heinrich, Tassiele Andréa; Cadena, Silvia Maria Suter Correia; Martinez, Glaucia Regina

    2017-01-01

    Melanoma is a rare and aggressive skin tumor; the survival of patients diagnosed late is fairly low. This high mortality rate is due to the characteristics of the cells that allow them to be resistant to radiotherapy and conventional chemotherapy, besides of being able to evade the immune system. Melanin, the pigment responsible for skin, hair and eye color, seems to be involved in this resistance. The main function of melanin is to protect the cells against ultraviolet (UV) light by absorbing this radiation and reactive oxygen species (ROS) scavenging. But this pigment may have also a role as photosensitizer, because when it is irradiated with UVA light (320-400 nm), the generation of ROS was detected. Besides, the melanogenesis stimulation on B16-F10 cells resulted in cell cycle arrest, induction of a quiescent state, change in the expression of several proteins and alterations on ADP/ATP ratio. The present study aimed to investigate the influence of melanogenesis stimulation in mitochondrial function of B16-F10 melanoma cells. Therefore, we analyzed cells respiration, mitochondrial membrane potential (Δψ_m) and mitochondria mass in B16-F10 melanoma cells stimulated with 0.4 mM L-tyrosine and 10 mM NH_4Cl. Our results showed that the induction of melanin synthesis was able to reduce significantly the oxygen consumption after 48 h of stimulation, without changes of mitochondrial membrane potential when compared to non-stimulated cells. Despite of respiration inhibition, the mitochondria mass was higher in cells with melanogenesis stimulation. We suggest that the stimulation in the melanin synthesis might be promoting the inhibition of electrons transport chain by some intermediate compound from the synthesis of the pigment and this effect could contribute to explain the entry in the quiescent state. - Highlights: • Melanoma pigmentation alters mitochondrial respiration. • Induction of melanin synthesis by 48 h do not change mitochondrial membrane potential

  18. Melanogenesis inhibits respiration in B16-F10 melanoma cells whereas enhances mitochondrial cell content

    Energy Technology Data Exchange (ETDEWEB)

    Meira, Willian Vanderlei; Heinrich, Tassiele Andréa; Cadena, Silvia Maria Suter Correia; Martinez, Glaucia Regina, E-mail: grmartinez@ufpr.br

    2017-01-01

    Melanoma is a rare and aggressive skin tumor; the survival of patients diagnosed late is fairly low. This high mortality rate is due to the characteristics of the cells that allow them to be resistant to radiotherapy and conventional chemotherapy, besides of being able to evade the immune system. Melanin, the pigment responsible for skin, hair and eye color, seems to be involved in this resistance. The main function of melanin is to protect the cells against ultraviolet (UV) light by absorbing this radiation and reactive oxygen species (ROS) scavenging. But this pigment may have also a role as photosensitizer, because when it is irradiated with UVA light (320-400 nm), the generation of ROS was detected. Besides, the melanogenesis stimulation on B16-F10 cells resulted in cell cycle arrest, induction of a quiescent state, change in the expression of several proteins and alterations on ADP/ATP ratio. The present study aimed to investigate the influence of melanogenesis stimulation in mitochondrial function of B16-F10 melanoma cells. Therefore, we analyzed cells respiration, mitochondrial membrane potential (Δψ{sub m}) and mitochondria mass in B16-F10 melanoma cells stimulated with 0.4 mM L-tyrosine and 10 mM NH{sub 4}Cl. Our results showed that the induction of melanin synthesis was able to reduce significantly the oxygen consumption after 48 h of stimulation, without changes of mitochondrial membrane potential when compared to non-stimulated cells. Despite of respiration inhibition, the mitochondria mass was higher in cells with melanogenesis stimulation. We suggest that the stimulation in the melanin synthesis might be promoting the inhibition of electrons transport chain by some intermediate compound from the synthesis of the pigment and this effect could contribute to explain the entry in the quiescent state. - Highlights: • Melanoma pigmentation alters mitochondrial respiration. • Induction of melanin synthesis by 48 h do not change mitochondrial membrane

  19. Enhancing Brain Lesions during Acute Optic Neuritis and/or Longitudinally Extensive Transverse Myelitis May Portend a Higher Relapse Rate in Neuromyelitis Optica Spectrum Disorders.

    Science.gov (United States)

    Orman, G; Wang, K Y; Pekcevik, Y; Thompson, C B; Mealy, M; Levy, M; Izbudak, I

    2017-05-01

    Neuromyelitis optica spectrum disorders are inflammatory demyelinating disorders with optic neuritis and/or longitudinally extensive transverse myelitis episodes. We now know that neuromyelitis optica spectrum disorders are associated with antibodies to aquaporin-4, which are highly concentrated on astrocytic end-feet at the blood-brain barrier. Immune-mediated disruption of the blood-brain barrier may manifest as contrast enhancement on brain MR imaging. We aimed to delineate the extent and frequency of contrast enhancement on brain MR imaging within 1 month of optic neuritis and/or longitudinally extensive transverse myelitis attacks and to correlate contrast enhancement with outcome measures. Brain MRIs of patients with neuromyelitis optica spectrum disorders were evaluated for patterns of contrast enhancement (periependymal, cloudlike, leptomeningeal, and so forth). The Fisher exact test was used to evaluate differences between the proportion of contrast enhancement in patients who were seropositive and seronegative for aquaporin-4 antibodies. The Mann-Whitney test was used to compare the annualized relapse rate and disease duration between patients with and without contrast enhancement and with and without seropositivity. Brain MRIs of 77 patients were evaluated; 59 patients (10 males, 49 females) were scanned within 1 month of optic neuritis and/or longitudinally extensive transverse myelitis attacks and were included in the analysis. Forty-eight patients were seropositive, 9 were seronegative, and 2 were not tested for aquaporin-4 antibodies. Having brain contrast enhancement of any type during an acute attack was significantly associated with higher annualized relapse rates ( P = .03) and marginally associated with shorter disease duration ( P = .05). Having periependymal contrast enhancement was significantly associated with higher annualized relapse rates ( P = .03). Brain MRIs of patients with neuromyelitis optica spectrum disorders with contrast

  20. Higher tacrolimus trough levels on days 2-5 post-renal transplant are associated with reduced rates of acute rejection.

    LENUS (Irish Health Repository)

    O'Seaghdha, C M

    2011-04-06

    We analyzed the association between whole-blood trough tacrolimus (TAC) levels in the first days post-kidney transplant and acute cellular rejection (ACR) rates. Four hundred and sixty-four consecutive, deceased-donor kidney transplant recipients were included. All were treated with a combination of TAC, mycophenolate mofetil and prednisolone. Patients were analyzed in four groups based on quartiles of the mean TAC on days 2 and 5 post-transplant: Group 1: median TAC 11 ng\\/mL (n = 122, range 2-13.5 ng\\/mL), Group 2: median 17 ng\\/mL (n = 123, range 14-20 ng\\/mL), Group 3: median 24 ng\\/mL (n = 108, range 20.5-27 ng\\/mL) and Group 4: median 33.5 ng\\/mL (n = 116, range 27.5-77.5 ng\\/mL). A graded reduction in the rates of ACR was observed for each incremental days 2-5 TAC. The one-yr ACR rate was 24.03% (95% CI 17.26-32.88), 22.20% (95% CI 15.78-30.70), 13.41% (95% CI 8.15-21.63) and 8.69% (95% CI 4.77-15.55) for Groups 1-4, respectively (p = 0.003). This study suggests that higher early TACs are associated with reduced rates of ACR at one yr.

  1. Estimation of fractional contribution of root respiration to a forest-floor CO2 flux using carbon isotopes

    International Nuclear Information System (INIS)

    Hachiya, Masashi; Moriizumi, Jun; Yamazawa, Hiromi

    2010-01-01

    Efflux of soil respired carbon dioxide(CO 2 ) is very important component for the global carbon cycle and dynamics of 14 C in environment, and to predict the global climate changes caused by increasing CO 2 concentrations in the atmosphere. There are two components that generate CO 2 in soil, soil organic matter decomposition and root respiration. Although the former is relatively well understood, the root-derived CO 2 efflux has not been evaluated sufficiently. The objective of our research is to estimate depth profile of the root respiration rate. Thus we developed a box model which calculates the depth profile. In this paper, we discussed about (1) the adequacy of calculated result by comparing it to the to observed soil respired CO 2 flux with trenching method and (2) sensitivity of the box model to uncertainty in the input data. The result showed that the depth profile of root respiration rate decreased with soil depth. This is attributed to the distribution of fine roots which dominate root respiration. The model results reasonable agreed with the measurement results and characteristics of root respiration. The output of the model was robust to the variation of the input data. (author)

  2. Respiration rate of gamma irradiation carnation cut flowers

    International Nuclear Information System (INIS)

    Kikuchi, Olivia Kimiko; Wiendl, Frederico Maximiliano; Todoriki, Setsuko; Nakahara, Kazuhiko; Haysahi, Toru

    1996-01-01

    The present paper presents the CO 2 production of the carnation cut flowers gamma-irradiated with a single dose of 750 Gy. The cut flowers were soaked in preservative solutions, containing germicides or germicides plus 2% sucrose. The irradiation did not change the CO 2 production and did not cause any visible flower damage. The sucrose exogenous supply extended the vase-life of both irradiated and non-irradiated carnations. These results indicated that Nora carnation cut flower can be irradiated with 750 Gy without commercial viability loss and that it is possible to use the radiation to disinfect this fresh product. (author)

  3. Interferon-free treatment for patients with chronic hepatitis C and autoimmune liver disease: higher SVR rates with special precautions for deterioration of autoimmune hepatitis.

    Science.gov (United States)

    Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Nakamoto, Shingo; Takahashi, Koji; Wu, Shuang; Sasaki, Reina; Haga, Yuki; Ogasawara, Sadahisa; Saito, Tomoko; Kobayashi, Kazufumi; Kiyono, Soichiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Chiba, Tetsuhiro; Maruyama, Hitoshi; Imazeki, Fumio; Moriyama, Mitsuhiko; Kato, Naoya

    2018-02-20

    Interferon-free treatment can achieve higher sustained virological response (SVR) rates, even in patients in whom hepatitis C virus (HCV) could not be eradicated in the interferon treatment era. Immune restoration in the liver is occasionally associated with HCV infection. We examined the safety and effects of interferon-free regimens on HCV patients with autoimmune liver diseases. All 7 HCV patients with autoimmune hepatitis (AIH) completed treatment and achieved SVR. Three patients took prednisolone (PSL) at baseline, and 3 did not take PSL during interferon-free treatment. In one HCV patient with AIH and cirrhosis, PSL were not administered at baseline, but she needed to take 40 mg/day PSL at week 8 for liver dysfunction. She also complained back pain and was diagnosed with vasospastic angina by coronary angiography at week 11. However, she completed interferon-free treatment. All 5 HCV patients with primary biliary cholangitis (PBC) completed treatment and achieved SVR. Three of these HCV patients with PBC were treated with UDCA during interferon-free treatment. Interferon-free regimens could result in higher SVR rates in HCV patients with autoimmune liver diseases. As interferon-free treatment for HCV may have an effect on hepatic immunity and activity of the autoimmune liver diseases, careful attention should be paid to unexpected adverse events in their treatments. Total 12 patients with HCV and autoimmune liver diseases [7 AIH and PBC], who were treated with interferon-free regimens, were retrospectively analyzed.

  4. Estimating Canopy Dark Respiration for Crop Models

    Science.gov (United States)

    Monje Mejia, Oscar Alberto

    2014-01-01

    Crop production is obtained from accurate estimates of daily carbon gain.Canopy gross photosynthesis (Pgross) can be estimated from biochemical models of photosynthesis using sun and shaded leaf portions and the amount of intercepted photosyntheticallyactive radiation (PAR).In turn, canopy daily net carbon gain can be estimated from canopy daily gross photosynthesis when canopy dark respiration (Rd) is known.

  5. LIMITATION OF SOIL RESPIRATION DURING DRY PERIOD

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