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Sample records for hibernating golden-mantled ground

  1. Effects of low temperature on breathing pattern and ventilatory responses during hibernation in the golden-mantled ground squirrel.

    Science.gov (United States)

    Webb, Cheryl L; Milsom, William K

    2017-07-01

    During entrance into hibernation in golden-mantled ground squirrels (Callospermophilus lateralis), ventilation decreases as metabolic rate and body temperature fall. Two patterns of respiration occur during deep hibernation. At 7 °C body temperature (T b ), a breathing pattern characterized by episodes of multiple breaths (20.6 ± 1.9 breaths/episode) separated by long apneas or nonventilatory periods (T nvp ) (mean = 11.1 ± 1.2 min) occurs, while at 4 °C T b , a pattern in which breaths are evenly distributed and separated by a relatively short T nvp (0.5 ± 0.05 min) occurs. Squirrels exhibiting each pattern have similar metabolic rates and levels of total ventilation (0.2 and 0.23 ml O 2 /hr/kg and 0.11 and 0.16 ml air/min/kg, respectively). Squirrels at 7 °C T b exhibit a significant hypoxic ventilatory response, while squirrels at 4 °C T b do not respond to hypoxia at any level of O 2 tested. Squirrels at both temperatures exhibit a significant hypercapnic ventilatory response, but the response is significantly reduced in the 4 °C T b squirrels. Carotid body denervation has little effect on the breathing patterns or on the hypercapnic ventilatory responses. It does reduce the magnitude and threshold for the hypoxic ventilatory response. Taken together the data suggest that (1) the fundamental rhythm generator remains functional at low temperatures; (2) the hypercapnic ventilatory response arises from central chemoreceptors that remain functional at very low temperatures; (3) the hypoxic ventilatory response arises from both carotid body and aortic chemoreceptors that are silenced at lower temperatures; and (4) there is a strong correlation between breathing pattern and chemosensitivity.

  2. [14C]2-deoxyglucose uptake in ground squirrel brain during hibernation

    International Nuclear Information System (INIS)

    Kilduff, T.S.; Sharp, F.R.; Heller, H.C.

    1982-01-01

    Autoradiographic patterns of [14C]2-deoxyglucose uptake are described throughout the brains of hibernating and euthermic ground squirrels. Autoradiographs of the brains of hibernating animals are generally homogeneous in comparison to euthermic animals; hence, the relative 2-deoxyglucose uptake (R2DGU) of gray to white matter for the majority of the 85 neural structures examined decreases during hibernation. Two categories of structures are identified as potentially important in hibernation: (1) structures that have the highest R2DGU during hibernation (cochlear nucleus, paratrigeminal nucleus, and superior colliculus) and (2) structures that undergo the least reduction in R2DGU in the transition from euthermia to hibernation (suprachiasmatic nucleus and lateral septal nucleus). The percentage of reduction in R2DGU that a structure undergoes in the transition from euthermia to hibernation is proportional to the R2DGU of that structure during euthermia. The suprachiasmatic, paratrigeminal, and cochlear nuclei undergo less of a reduction than would be predicted from this relationship and may be particularly important during hibernation. Sensory nuclei that receive primary afferent projections are among the structures with the highest R2DGU during hibernation. These metabolically active structures may be responsible for the sensitivity of the hibernator to environmental stimuli

  3. Radiosensitivity of ileum crypt cells in hibernating, arousing, and awake ground squirrels (Citellus tridecemlineatus)

    International Nuclear Information System (INIS)

    Jaroslow, B.N.; Michael Fry, R.J.; Suhrbier, K.M.; Sallese, A.R.

    1976-01-01

    Radiosensitivity of ileal crypt cells, to 60 Co gamma radiation, was studied in ground squirrels (Citellus tridecemlineatus) during hibernation, arousal, and the euthermic state. Survival of ileal crypt cells, assayed by the microcolony technique from stained transverse sections of ileum, was greater in animals irradiated in hibernation or 1 hr after initiation of arousal from hibernation. Crypt survival returned to the level of irradiated nonhibernating controls in animals irradiated 3 to 7 hr after initiation of arousal. Over the exposure range of 1500 to 2400 R, the survival of crypt cells for euthermic controls gave a D 0 = 133 +- 12 R and for animals irradiated in hibernation it gave a D 0 = 487 +- 92 R. In animals irradiated 1 hr after initiation of arousal, when core temperature is within the range of euthermic controls, crypt survival was almost as high as in the hibernators. These results suggest that the increased resistance of ileal crypt cells in hibernating animals could be due to hypoxia, although not direct evidence for hypoxia in hibernation was established. The changes in mitotic index of ileal crypt cells during hibernation and arousal indicate an alteration in the distribution of cells in the phases of the cycle. This change in distribution may also have contributed to the increased radioresistance of hibernators

  4. WARMING UP FOR SLEEP - GROUND-SQUIRRELS SLEEP DURING AROUSALS FROM HIBERNATION

    NARCIS (Netherlands)

    DAAN, S; BARNES, BM; STRIJKSTRA, AM

    1991-01-01

    Hypothermia during mammalian hibernation is periodically interrupted by arousals to euthermy, the function of which is unknown. We report that arctic ground squirrels (Spermophilus parryii) consistently sleep during these arousals, and that their EEG shows the decrease in slow wave activity

  5. Differential regulation of glomerular and interstitial endothelial nitric oxide synthase expression in the kidney of hibernating ground squirrel.

    Science.gov (United States)

    Sandovici, Maria; Henning, Robert H; Hut, Roelof A; Strijkstra, Arjen M; Epema, Anne H; van Goor, Harry; Deelman, Leo E

    2004-09-01

    Hibernating animals transiently reduce renal function during their hypothermic periods (torpor), while completely restoring it during their periodical rewarming to euthermia (arousal). Moreover, structural integrity of the kidney is preserved throughout the hibernation. Nitric oxide (NO) generated by endothelial nitric oxide synthase (eNOS) is a crucial vasodilatory mediator and a protective factor in the kidney. We investigated renal NOS expression in hibernating European ground squirrels after 1 day and 7 days of torpor (torpor short, TS, and torpor long, TL, respectively), at 1.5 and at 10 h of rewarming (arousal short, AS, and arousal long, AL, respectively), and in continuously euthermic animals after hibernation (EU). For that purpose, we performed NOS activity assay, immunohistochemistry and real-time PCR analysis. Immunohistochemistry revealed a decreased glomerular eNOS expression in hibernating animals (TS, TL, AS, and AL) compared to non-hibernating animals (EU, p EU. In all methods used, torpid and aroused squirrels did not differ. These results demonstrate differential regulation of eNOS in glomeruli and interstitium of hibernating animals, which is unaffected during arousal. The differential regulation of eNOS may serve to reduce ultrafiltration without jeopardizing tubular structures during hibernation.

  6. Up-regulation of Long Non-coding RNA TUG1 in Hibernating Thirteen-lined Ground Squirrels

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    Jacques J. Frigault

    2016-04-01

    Full Text Available Mammalian hibernation is associated with multiple physiological, biochemical, and molecular changes that allow animals to endure colder temperatures. We hypothesize that long non-coding RNAs (lncRNAs, a group of non-coding transcripts with diverse functions, are differentially expressed during hibernation. In this study, expression levels of lncRNAs H19 and TUG1 were assessed via qRT-PCR in liver, heart, and skeletal muscle tissues of the hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus. TUG1 transcript levels were significantly elevated 1.94-fold in skeletal muscle of hibernating animals when compared with euthermic animals. Furthermore, transcript levels of HSF2 also increased 2.44-fold in the skeletal muscle in hibernating animals. HSF2 encodes a transcription factor that can be negatively regulated by TUG1 levels and that influences heat shock protein expression. Thus, these observations support the differential expression of the TUG1–HSF2 axis during hibernation. To our knowledge, this study provides the first evidence for differential expression of lncRNAs in torpid ground squirrels, adding lncRNAs as another group of transcripts modulated in this mammalian species during hibernation.

  7. Up-regulation of Long Non-coding RNA TUG1 in Hibernating Thirteen-lined Ground Squirrels.

    Science.gov (United States)

    Frigault, Jacques J; Lang-Ouellette, Daneck; Morin, Pier

    2016-04-01

    Mammalian hibernation is associated with multiple physiological, biochemical, and molecular changes that allow animals to endure colder temperatures. We hypothesize that long non-coding RNAs (lncRNAs), a group of non-coding transcripts with diverse functions, are differentially expressed during hibernation. In this study, expression levels of lncRNAsH19 and TUG1 were assessed via qRT-PCR in liver, heart, and skeletal muscle tissues of the hibernating thirteen-lined ground squirrels (Ictidomys tridecemlineatus). TUG1 transcript levels were significantly elevated 1.94-fold in skeletal muscle of hibernating animals when compared with euthermic animals. Furthermore, transcript levels of HSF2 also increased 2.44-fold in the skeletal muscle in hibernating animals. HSF2 encodes a transcription factor that can be negatively regulated by TUG1 levels and that influences heat shock protein expression. Thus, these observations support the differential expression of the TUG1-HSF2 axis during hibernation. To our knowledge, this study provides the first evidence for differential expression of lncRNAs in torpid ground squirrels, adding lncRNAs as another group of transcripts modulated in this mammalian species during hibernation. Copyright © 2016 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.

  8. Metabolic hormone FGF21 is induced in ground squirrels during hibernation but its overexpression is not sufficient to cause torpor.

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    Bethany T Nelson

    Full Text Available Hibernation is a natural adaptation that allows certain mammals to survive physiological extremes that are lethal to humans. Near freezing body temperatures, heart rates of 3-10 beats per minute, absence of food consumption, and depressed metabolism are characteristic of hibernation torpor bouts that are periodically interrupted by brief interbout arousals (IBAs. The molecular basis of torpor induction is unknown, however starved mice overexpressing the metabolic hormone fibroblast growth factor 21 (FGF21 promote fat utilization, reduce body temperature, and readily enter torpor-all hallmarks of mammalian hibernation. In this study we cloned FGF21 from the naturally hibernating thirteen-lined ground squirrel (Ictidomys tridecemlineatus and found that levels of FGF21 mRNA in liver and FGF21 protein in serum are elevated during hibernation torpor bouts and significantly elevated during IBAs compared to summer active animals. The effects of artificially elevating circulating FGF21 concentrations 50 to 100-fold via adenoviral-mediated overexpression were examined at three different times of the year. This is the first time that a transgenic approach has been used in a natural hibernator to examine mechanistic aspects of hibernation. Surgically implanted transmitters measured various metrics of the hibernation phenotype over a 7-day period including changes in motor activity, heart rate and core body temperature. In April fed-state animals, FGF21 overexpression decreased blood insulin and free fatty acid concentrations, effects similar to those seen in obese mice. However, elevated FGF21 concentrations did not cause torpor in these fed-state animals nor did they cause torpor or affect metabolic parameters in fasted-state animals in March/April, August or October. We conclude that FGF21 is strongly regulated during torpor and IBA but that its overexpression is not sufficient to cause torpor in naturally hibernating ground squirrels.

  9. Suspension of Mitotic Activity in Dentate Gyrus of the Hibernating Ground Squirrel

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    Victor I. Popov

    2011-01-01

    Full Text Available Neurogenesis occurs in the adult mammalian hippocampus, a region of the brain important for learning and memory. Hibernation in Siberian ground squirrels provides a natural model to study mitosis as the rapid fall in body temperature in 24 h (from 35-36°C to +4–6°C permits accumulation of mitotic cells at different stages of the cell cycle. Histological methods used to study adult neurogenesis are limited largely to fixed tissue, and the mitotic state elucidated depends on the specific phase of mitosis at the time of day. However, using an immunohistochemical study of doublecortin (DCX and BrdU-labelled neurons, we demonstrate that the dentate gyrus of the ground squirrel hippocampus contains a population of immature cells which appear to possess mitotic activity. Our data suggest that doublecortin-labelled immature cells exist in a mitotic state and may represent a renewable pool for generation of new neurons within the dentate gyrus.

  10. Cytoskeletal Regulation Dominates Temperature-Sensitive Proteomic Changes of Hibernation in Forebrain of 13-Lined Ground Squirrels

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    Hindle, Allyson G.; Martin, Sandra L.

    2013-01-01

    13-lined ground squirrels, Ictidomys tridecemlineatus, are obligate hibernators that transition annually between summer homeothermy and winter heterothermy – wherein they exploit episodic torpor bouts. Despite cerebral ischemia during torpor and rapid reperfusion during arousal, hibernator brains resist damage and the animals emerge neurologically intact each spring. We hypothesized that protein changes in the brain underlie winter neuroprotection. To identify candidate proteins, we applied a sensitive 2D gel electrophoresis method to quantify protein differences among forebrain extracts prepared from ground squirrels in two summer, four winter and fall transition states. Proteins that differed among groups were identified using LC-MS/MS. Only 84 protein spots varied significantly among the defined states of hibernation. Protein changes in the forebrain proteome fell largely into two reciprocal patterns with a strong body temperature dependence. The importance of body temperature was tested in animals from the fall; these fall animals use torpor sporadically with body temperatures mirroring ambient temperatures between 4 and 21°C as they navigate the transition between summer homeothermy and winter heterothermy. Unlike cold-torpid fall ground squirrels, warm-torpid individuals strongly resembled the homeotherms, indicating that the changes observed in torpid hibernators are defined by body temperature, not torpor per se. Metabolic enzymes were largely unchanged despite varied metabolic activity across annual and torpor-arousal cycles. Instead, the majority of the observed changes were cytoskeletal proteins and their regulators. While cytoskeletal structural proteins tended to differ seasonally, i.e., between summer homeothermy and winter heterothermy, their regulatory proteins were more strongly affected by body temperature. Changes in the abundance of various isoforms of the microtubule assembly and disassembly regulatory proteins dihydropyrimidinase

  11. Cytoskeletal regulation dominates temperature-sensitive proteomic changes of hibernation in forebrain of 13-lined ground squirrels.

    Directory of Open Access Journals (Sweden)

    Allyson G Hindle

    Full Text Available 13-lined ground squirrels, Ictidomys tridecemlineatus, are obligate hibernators that transition annually between summer homeothermy and winter heterothermy - wherein they exploit episodic torpor bouts. Despite cerebral ischemia during torpor and rapid reperfusion during arousal, hibernator brains resist damage and the animals emerge neurologically intact each spring. We hypothesized that protein changes in the brain underlie winter neuroprotection. To identify candidate proteins, we applied a sensitive 2D gel electrophoresis method to quantify protein differences among forebrain extracts prepared from ground squirrels in two summer, four winter and fall transition states. Proteins that differed among groups were identified using LC-MS/MS. Only 84 protein spots varied significantly among the defined states of hibernation. Protein changes in the forebrain proteome fell largely into two reciprocal patterns with a strong body temperature dependence. The importance of body temperature was tested in animals from the fall; these fall animals use torpor sporadically with body temperatures mirroring ambient temperatures between 4 and 21°C as they navigate the transition between summer homeothermy and winter heterothermy. Unlike cold-torpid fall ground squirrels, warm-torpid individuals strongly resembled the homeotherms, indicating that the changes observed in torpid hibernators are defined by body temperature, not torpor per se. Metabolic enzymes were largely unchanged despite varied metabolic activity across annual and torpor-arousal cycles. Instead, the majority of the observed changes were cytoskeletal proteins and their regulators. While cytoskeletal structural proteins tended to differ seasonally, i.e., between summer homeothermy and winter heterothermy, their regulatory proteins were more strongly affected by body temperature. Changes in the abundance of various isoforms of the microtubule assembly and disassembly regulatory proteins

  12. 14C-2-deoxyglucose uptake in the ground squirrel brain during entrance to and arousal from hibernation

    International Nuclear Information System (INIS)

    Kilduff, T.S.; Miller, J.D.; Radeke, C.M.; Sharp, F.R.; Heller, H.C.

    1990-01-01

    Neuronal activity underlying various phases of the mammalian hibernation cycle was investigated using the 14 C-2-deoxyglucose (2DG) method. Relative 2DG uptake (R2DGU) values were computed for 96 brain regions across 7 phases of the hibernation cycle: euthermia, 3 body temperature (Tb) intervals during entrance into hibernation, stable deep hibernation, and 2 Tb intervals during arousal from hibernation. Multivariate statistical techniques were employed to identify objectively groups of brain regions whose R2DGU values showed a similar pattern across all phases of hibernation. Factor analysis revealed that most of the variability in R2DGU values for the 96 brain regions across the entire cycle could be accounted for by 3 principal factors. These factors could accurately discriminate the various phases of hibernation on the basis of the R2DGU values alone. Three hypothalamic and 3 cortical regions were identified as possibly mediating the entrance into hibernation because they underwent a change in R2DGU early in entrance into hibernation and loaded strongly on one of the principal factors. Another 4 hypothalamic regions were similarly identified as possibly causally involved in the arousal from hibernation. These results, coupled with characteristic changes in ordinal rank of the 96 brain regions in each phase of hibernation, support the concept that mammalian hibernation is an active, integrated orchestration of neurophysiological events rather than a state entered through a passive process

  13. Beginning Hibernate

    CERN Document Server

    Linwood, Jeff

    2010-01-01

    Beginning Hibernate, Second Edition is ideal if you're experienced in Java with databases (the traditional, or "connected," approach), but new to open source, lightweight Hibernate-the de facto object-relational mapping and database-oriented application development framework. This book packs in brand-new information about the latest release of the Hibernate 3.5 persistence layer and provides a clear introduction to the current standard for object-relational persistence in Java. And since the book keeps its focus on Hibernate without wasting time on nonessential third-party tools, you

  14. Beginning Hibernate

    CERN Document Server

    Minter, Dave; Ottinger, Joseph

    2014-01-01

    Beginning Hibernate, Third Edition is ideal if you're experienced in Java with databases (the traditional, or "connected," approach), but new to open-source, lightweight Hibernate, a leading object-relational mapping and database-oriented application development framework.This book packs in information about the release of the Hibernate 4.x persistence layer and provides a clear introduction to the current standard for object-relational persistence in Java. And since the book keeps its focus on Hibernate without wasting time on nonessential third-party tools, you'll be able to immediately star

  15. Good and bad in the hibernating brain

    NARCIS (Netherlands)

    Strijkstra, AM

    2006-01-01

    Hibernators survive long periods of time without behavioural activity. To minimize energy expenditure, hibernators use the natural hypometabolic state of torpor. Deep torpor in ground squirrels is accompanied by reduction of brain activity, and is associated with changes in electrical activity

  16. Hibernate A Developer's Notebook

    CERN Document Server

    Elliott, James

    2004-01-01

    Do you enjoy writing software, except for the database code? Hibernate:A Developer's Notebook is for you. Database experts may enjoy fiddling with SQL, but you don't have to--the rest of the application is the fun part. And even database experts dread the tedious plumbing and typographical spaghetti needed to put their SQL into a Java program. Hibernate: A Developers Notebook shows you how to use Hibernate to automate persistence: you write natural Java objects and some simple configuration files, and Hibernate automates all the interaction between your objects and the database. You don't

  17. Progressive activation of paratrigeminal nucleus during entrance to hibernation

    International Nuclear Information System (INIS)

    Kilduff, T.S.; Sharp, F.R.; Heller, H.C.

    1988-01-01

    The paratrigeminal nucleus (Pa5) undergoes a progressive increase in its uptake of 2-[ 14 C]deoxyglucose (2DG) relative to other brain structures during entrance to hibernation in the ground squirrel. This highly significant increase results in the Pa5 becoming the most highly labeled brain region during hibernation, even though it exhibits one of the lowest levels of 2DG uptake in the brain during the nonhibernating state. The progressive activation of the Pa5 observed during entrance is reversed during arousal from hibernation. These observations and the neuroanatomical projections of the Pa5 implicate this nucleus as playing a role in the entrance and maintenance of the hibernating state

  18. The range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878): distributions and sympatry of four tamarin species in Colombia, Ecuador, and northern Peru

    Science.gov (United States)

    Matauschek, Christian; Aquino, Rolando; Encarnación, Filomeno; Heymann, Eckhard W.; de la Torre, Stella; Mittermeier, Russell A.

    2010-01-01

    A detailed understanding of the range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878), in Amazonian Peru and Ecuador is of particular relevance, not only because it is poorly known but also because it was on the basis of its supposed sympatry with the saddleback tamarin (S. fuscicollis lagonotus) that Thorington (Am J Primatol 15:367–371, 1988) argued that it is a distinct species rather than a saddleback tamarin subspecies, as was believed by Hershkovitz (Living new world monkeys, vol I. The University of Chicago Press, Chicago, 1977). A number of surveys have been carried out since 1988 in the supposed range of S. tripartitus, in both Ecuador and Peru. Here we summarize and discuss these issues and provide a new suggestion for the geographic range of this species; that is, between the ríos Napo and Curaray in Peru and extending east into Ecuador. We also review current evidence for the distributions of Spix’s black-mantle tamarin (S. nigricollis nigricollis), Graells’ black-mantle tamarin (S. n. graellsi), and the saddleback tamarin (S. fuscicollis lagonotus), which are also poorly known, and examine the evidence regarding sympatry between them. We conclude that despite the existence of a number of specimens with collecting localities that indicate overlap in their geographic ranges, the fact that the four tamarin species are of similar size and undoubtedly very similar in their feeding habits militates strongly against the occurrence of sympatry among them. PMID:20878203

  19. The range of the golden-mantle tamarin, Saguinus tripartitus (Milne-Edwards, 1878): distributions and sympatry of four tamarins in Colombia, Ecuador, and northern Peru [corrected].

    Science.gov (United States)

    Rylands, Anthony B; Matauschek, Christian; Aquino, Rolando; Encarnación, Filomeno; Heymann, Eckhard W; de la Torre, Stella; Mittermeier, Russell A

    2011-01-01

    A detailed understanding of the range of the golden-mantle tamarin, Saguinus tripartitus (Milne Edwards, 1878), in Amazonian Peru and Ecuador is of particular relevance, not only because it is poorly known but also because it was on the basis of its supposed sympatry with the saddleback tamarin (S. fuscicollis lagonotus) that Thorington (Am J Primatol 15:367-371, 1988) argued that it is a distinct species rather than a saddleback tamarin subspecies, as was believed by Hershkovitz (Living new world monkeys, vol I. The University of Chicago Press, Chicago, 1977). A number of surveys have been carried out since 1988 in the supposed range of S. tripartitus, in both Ecuador and Peru. Here we summarize and discuss these issues and provide a new suggestion for the geographic range of this species; that is, between the ríos Napo and Curaray in Peru and extending east into Ecuador. We also review current evidence for the distributions of Spix's black-mantle tamarin (S. nigricollis nigricollis), Graells' black-mantle tamarin (S. n. graellsi), and the saddleback tamarin (S. fuscicollis lagonotus), which are also poorly known, and examine the evidence regarding sympatry between them. We conclude that despite the existence of a number of specimens with collecting localities that indicate overlap in their geographic ranges, the fact that the four tamarins are [corrected] of similar size and undoubtedly very similar in their feeding habits militates strongly against the occurrence of sympatry among them.

  20. Mammalian hibernation: lessons for organ preparation?

    Science.gov (United States)

    Green, C

    2000-01-01

    The adaptations to low environmental temperatures exhibited in mammalian hibernation are many and varied, and involve molecular and cellular mechanisms as well as the systematic physiology of the whole organism. Natural torpidity is characterised by a profound reduction in body temperature and other functions lasting from a few hours to several weeks. Controlled reduction of heart rate, respiration and oxygen consumption is followed by the fall in body temperature. However, thermoregulation persists such that a decrease in ambient temperature below dangerous levels typically triggers arousal, and shivering and non-shivering thermogenesis from brown fat provide the heat to restore body temperature to normal levels. Many of the cellular mechanisms for survival are similar to those brought into play during medium-term storage of organs destined for transplantation. For example maintenance of ionic regulation and membrane fluxes is fundamental to cell survival and function at low body temperatures. Differences between hibernating and non-hibernating species are marked by differences in Na+/K+ transport and Ca++pumps. These in turn are probably associated with alterations in the lipoproteins of the plasma membrane and inner mitochondrial membrane. We have accordingly conducted a series of pilot studies in captured Richardson's ground squirrels kept in laboratory conditions as a model for hypothermic organ preservation. Tissue function was compared during the summer (non-hibernating season) with that in the winter when the animals could be: (i) in deep hibernation in a cold chamber at 4 degree C; (ii) maintained in an ambient temperature of 4 degree C but active and awake; or (iii) active at an ambient temperature of 22 degree C. The studies involved: whole animal monitoring of standard physiological parameters; whole organ (kidney) storage and transplantation for viability assessment; storage and functional assessment on an ex vivo test circuit with capacity for

  1. Hibernation and gas exchange.

    Science.gov (United States)

    Milsom, William K; Jackson, Donald C

    2011-01-01

    Hibernation in endotherms and ectotherms is characterized by an energy-conserving metabolic depression due to low body temperatures and poorly understood temperature-independent mechanisms. Rates of gas exchange are correspondly reduced. In hibernating mammals, ventilation falls even more than metabolic rate leading to a relative respiratory acidosis that may contribute to metabolic depression. Breathing in some mammals becomes episodic and in some small mammals significant apneic gas exchange may occur by passive diffusion via airways or skin. In ectothermic vertebrates, extrapulmonary gas exchange predominates and in reptiles and amphibians hibernating underwater accounts for all gas exchange. In aerated water diffusive exchange permits amphibians and many species of turtles to remain fully aerobic, but hypoxic conditions can challenge many of these animals. Oxygen uptake into blood in both endotherms and ectotherms is enhanced by increased affinity of hemoglobin for O₂ at low temperature. Regulation of gas exchange in hibernating mammals is predominately linked to CO₂/pH, and in episodic breathers, control is principally directed at the duration of the apneic period. Control in submerged hibernating ectotherms is poorly understood, although skin-diffusing capacity may increase under hypoxic conditions. In aerated water blood pH of frogs and turtles either adheres to alphastat regulation (pH ∼8.0) or may even exhibit respiratory alkalosis. Arousal in hibernating mammals leads to restoration of euthermic temperature, metabolic rate, and gas exchange and occurs periodically even as ambient temperatures remain low, whereas body temperature, metabolic rate, and gas exchange of hibernating ectotherms are tightly linked to ambient temperature. © 2011 American Physiological Society.

  2. Getting Started with Hibernate 3

    CERN Document Server

    Elliott, James

    2008-01-01

    Hibernate has clearly arrived. Are you ready to benefit from its simple way of working with relational databases as Java objects? This PDF updates the introductory material from the award-winning Hibernate: A Developer's Notebook to teach you how to jump right in and get productive with the current release of Hibernate. You'll be walked through the ins and outs of setting up Hibernate and some related tools that make it easier to use--and that may give you new ideas about how to store information in your Java programs. In short, this PDF gives you exactly the information you need to start u

  3. Spin label evidence for the role of lysoglycerophosphatides in cellular membranes of hibernating mammals

    Energy Technology Data Exchange (ETDEWEB)

    Keith, A D [Pennsylvania State Univ., University Park; Aloia, R C; Lyons, J; Snipes, W; Pengelley, E T

    1975-01-01

    The phospholipid composition of ground squirrel heart muscle changes during hibernation: more lysoglycerophosphatides are found in the hibernating state than in the active state. Phase transitions inferred from spin label motion occur in the usual manner typical of mammalian mitochondria for the mitochondria and mitochondrial lipids from active squirrels. However, a conspicuous absence of a spin label-detectable phase transition is observed in equivalent preparations from hibernating animals. The addition of lysolecithin to preparations from active squirrels removes the break and induces a straight line in the Arrhenius plot. The lack of a spin label-detectable phase transition in hibernating animals, therefore, is attributed to an increased content of lysoglycerophosphatides present in the phospholipids during hibernation.

  4. Prioritization of skeletal muscle growth for emergence from hibernation.

    Science.gov (United States)

    Hindle, Allyson G; Otis, Jessica P; Epperson, L Elaine; Hornberger, Troy A; Goodman, Craig A; Carey, Hannah V; Martin, Sandra L

    2015-01-15

    Mammalian hibernators provide an extreme example of naturally occurring challenges to muscle homeostasis. The annual hibernation cycle is characterized by shifts between summer euthermy with tissue anabolism and accumulation of body fat reserves, and winter heterothermy with fasting and tissue catabolism. The circannual patterns of skeletal muscle remodelling must accommodate extended inactivity during winter torpor, the motor requirements of transient winter active periods, and sustained activity following spring emergence. Muscle volume in thirteen-lined ground squirrels (Ictidomys tridecemlineatus) calculated from MRI upper hindlimb images (n=6 squirrels, n=10 serial scans) declined from hibernation onset, reaching a nadir in early February. Paradoxically, mean muscle volume rose sharply after February despite ongoing hibernation, and continued total body mass decline until April. Correspondingly, the ratio of muscle volume to body mass was steady during winter atrophy (October-February) but increased (+70%) from February to May, which significantly outpaced changes in liver or kidney examined by the same method. Generally stable myocyte cross-sectional area and density indicated that muscle remodelling is well regulated in this hibernator, despite vastly altered seasonal fuel and activity levels. Body composition analysis by echo MRI showed lean tissue preservation throughout hibernation amid declining fat mass by the end of winter. Muscle protein synthesis was 66% depressed in early but not late winter compared with a summer fasted baseline, while no significant changes were observed in the heart, liver or intestine, providing evidence that could support a transition in skeletal muscle regulation between early and late winter, prior to spring emergence and re-feeding. © 2015. Published by The Company of Biologists Ltd.

  5. The relationship of sleep with temperature and metabolic rate in a hibernating primate.

    Directory of Open Access Journals (Sweden)

    Andrew D Krystal

    Full Text Available STUDY OBJECTIVES: It has long been suspected that sleep is important for regulating body temperature and metabolic-rate. Hibernation, a state of acute hypothermia and reduced metabolic-rate, offers a promising system for investigating those relationships. Prior studies in hibernating ground squirrels report that, although sleep occurs during hibernation, it manifests only as non-REM sleep, and only at relatively high temperatures. In our study, we report data on sleep during hibernation in a lemuriform primate, Cheirogaleus medius. As the only primate known to experience prolonged periods of hibernation and as an inhabitant of more temperate climates than ground squirrels, this animal serves as an alternative model for exploring sleep temperature/metabolism relationships that may be uniquely relevant to understanding human physiology. MEASUREMENTS AND RESULTS: We find that during hibernation, non-REM sleep is absent in Cheirogaleus. Rather, periods of REM sleep occur during periods of relatively high ambient temperature, a pattern opposite of that observed in ground squirrels. Like ground squirrels, however, EEG is marked by ultra-low voltage activity at relatively low metabolic-rates. CONCLUSIONS: These findings confirm a sleep-temperature/metabolism link, though they also suggest that the relationship of sleep stage with temperature/metabolism is flexible and may differ across species or mammalian orders. The absence of non-REM sleep suggests that during hibernation in Cheirogaleus, like in the ground squirrel, the otherwise universal non-REM sleep homeostatic response is greatly curtailed or absent. Lastly, ultra-low voltage EEG appears to be a cross-species marker for extremely low metabolic-rate, and, as such, may be an attractive target for research on hibernation induction.

  6. Hibernation for space travel: Impact on radioprotection

    Science.gov (United States)

    Cerri, Matteo; Tinganelli, Walter; Negrini, Matteo; Helm, Alexander; Scifoni, Emanuele; Tommasino, Francesco; Sioli, Maximiliano; Zoccoli, Antonio; Durante, Marco

    2016-11-01

    Hibernation is a state of reduced metabolic activity used by some animals to survive in harsh environmental conditions. The idea of exploiting hibernation for space exploration has been proposed many years ago, but in recent years it is becoming more realistic, thanks to the introduction of specific methods to induce hibernation-like conditions (synthetic torpor) in non-hibernating animals. In addition to the expected advantages in long-term exploratory-class missions in terms of resource consumptions, aging, and psychology, hibernation may provide protection from cosmic radiation damage to the crew. Data from over half century ago in animal models suggest indeed that radiation effects are reduced during hibernation. We will review the mechanisms of increased radioprotection in hibernation, and discuss possible impact on human space exploration.

  7. Suppression of guinea pig ileum induced contractility by plasma albumin of hibernators

    Science.gov (United States)

    Bruce, David S.; Ambler, Douglas L.; Henschel, Timothy M.; Oeltgen, Peter R.; Nilekani, Sita P.; Amstrup, Steven C.

    1992-01-01

    Previous studies suggest that hibernation may be regulated by internal opioids and that the putative “hibernation induction trigger” (HIT) may itself be an opioid. This study examined the effect of plasma albumin (known to bind HIT) on induced contractility of the guinea pig ileum muscle strip. Morphine (400 nM) depressed contractility and 100 nM naloxone restored it. Ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bears produced similar inhibition, with partial reversal by naloxone. Five hundredths mg of d-Ala2-d-Leu5-enkephalin (DADLE) also inhibited contractility and naloxone reversed it. Conclusions are that hibernating individuals of these species contain an HIT substance that is opioid in nature and summer animals do not; an endogenous opioid similar to leu-enkephalin may be the HIT compound or give rise to it.

  8. Hibernate Recipes A Problem-Solution Approach

    CERN Document Server

    Mak, Gary

    2010-01-01

    Hibernate continues to be the most popular out-of-the-box framework solution for Java Persistence and data/database accessibility techniques and patterns. It is used for e-commerce-based web applications as well as heavy-duty transactional systems for the enterprise. Gary Mak, the author of the best-selling Spring Recipes, now brings you Hibernate Recipes. This book contains a collection of code recipes and templates for learning and building Hibernate solutions for you and your clients. This book is your pragmatic day-to-day reference and guide for doing all things involving Hibernate. There

  9. Differential Gene Expression in Mammalian Liver during Hibernation

    National Research Council Canada - National Science Library

    Martin, Sandra

    1998-01-01

    Hibernation is an adaptive strategy employed by some mammals to escape the cold. During hibernation, heart, respiratory and metabolic rates plummet, and core body temperatures can approach freezing...

  10. Hibernation : the immune system at rest?

    NARCIS (Netherlands)

    Bouma, Hjalmar R.; Carey, Hannah V.; Kroese, Frans G. M.

    2010-01-01

    Mammalian hibernation consists of torpor phases when metabolism is severely depressed, and T can reach as low as approximately -2 degrees C, interrupted by euthermic arousal phases. Hibernation affects the function of the innate and the adaptive immune systems. Torpor drastically reduces numbers of

  11. The physiological link between metabolic rate depression and tau phosphorylation in mammalian hibernation.

    Directory of Open Access Journals (Sweden)

    Jens T Stieler

    Full Text Available Abnormal phosphorylation and aggregation of tau protein are hallmarks of a variety of neurological disorders, including Alzheimer's disease (AD. Increased tau phosphorylation is assumed to represent an early event in pathogenesis and a pivotal aspect for aggregation and formation of neurofibrillary tangles. However, the regulation of tau phosphorylation in vivo and the causes for its increased stage of phosphorylation in AD are still not well understood, a fact that is primarily based on the lack of adequate animal models. Recently we described the reversible formation of highly phosphorylated tau protein in hibernating European ground squirrels. Hence, mammalian hibernation represents a model system very well suited to study molecular mechanisms of both tau phosphorylation and dephosphorylation under in vivo physiological conditions. Here, we analysed the extent and kinetics of hibernation-state dependent tau phosphorylation in various brain regions of three species of hibernating mammals: arctic ground squirrels, Syrian hamsters and black bears. Overall, tau protein was highly phosphorylated in torpor states and phosphorylation levels decreased after arousal in all species. Differences between brain regions, hibernation-states and phosphosites were observed with respect to degree and kinetics of tau phosphorylation. Furthermore, we tested the phosphate net turnover of tau protein to analyse potential alterations in kinase and/or phosphatase activities during hibernation. Our results demonstrate that the hibernation-state dependent phosphorylation of tau protein is specifically regulated but involves, in addition, passive, temperature driven regulatory mechanisms. By determining the activity-state profile for key enzymes of tau phosphorylation we could identify kinases potentially involved in the differentially regulated, reversible tau phosphorylation that occurs during hibernation. We show that in black bears hibernation is associated with

  12. Dissimilarity of slow-wave activity enhancement by torpor and sleep deprivation in a hibernator

    NARCIS (Netherlands)

    Strijkstra, AM; Daan, S

    1998-01-01

    Sleep regulation processes have been hypothesized to be involved in function and timing of arousal episodes in hibernating ground squirrels. We investigated the importance of sleep regulation during arousal episodes by sleep deprivation experiments. After sleep deprivation of 4, 12, and 24 h,

  13. Biochemical adaptations of mammalian hibernation: exploring squirrels as a perspective model for naturally induced reversible insulin resistance

    Energy Technology Data Exchange (ETDEWEB)

    Wu, C-W.; Biggar, K.K.; Storey, K.B. [Carleton University, Department of Biology, Institute of Biochemistry, Ottawa, ON (Canada)

    2013-01-28

    An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans.

  14. Biochemical adaptations of mammalian hibernation: exploring squirrels as a perspective model for naturally induced reversible insulin resistance

    International Nuclear Information System (INIS)

    Wu, C-W.; Biggar, K.K.; Storey, K.B.

    2013-01-01

    An important disease among human metabolic disorders is type 2 diabetes mellitus. This disorder involves multiple physiological defects that result from high blood glucose content and eventually lead to the onset of insulin resistance. The combination of insulin resistance, increased glucose production, and decreased insulin secretion creates a diabetic metabolic environment that leads to a lifetime of management. Appropriate models are critical for the success of research. As such, a unique model providing insight into the mechanisms of reversible insulin resistance is mammalian hibernation. Hibernators, such as ground squirrels and bats, are excellent examples of animals exhibiting reversible insulin resistance, for which a rapid increase in body weight is required prior to entry into dormancy. Hibernator studies have shown differential regulation of specific molecular pathways involved in reversible resistance to insulin. The present review focuses on this growing area of research and the molecular mechanisms that regulate glucose homeostasis, and explores the roles of the Akt signaling pathway during hibernation. Here, we propose a link between hibernation, a well-documented response to periods of environmental stress, and reversible insulin resistance, potentially facilitated by key alterations in the Akt signaling network, PPAR-γ/PGC-1α regulation, and non-coding RNA expression. Coincidentally, many of the same pathways are frequently found to be dysregulated during insulin resistance in human type 2 diabetes. Hence, the molecular networks that may regulate reversible insulin resistance in hibernating mammals represent a novel approach by providing insight into medical treatment of insulin resistance in humans

  15. Differences in mitochondrial function and morphology during cooling and rewarming between hibernator and non-hibernator derived kidney epithelial cells

    NARCIS (Netherlands)

    Hendriks, Koen D. W.; Lupi, Eleonora; Hardenberg, Maarten C.; Hoogstra-Berends, Femke; Deelman, Leo E.; Henning, Robert H.

    2017-01-01

    Hibernators show superior resistance to ischemia and hypothermia, also outside the hibernation season. Therefore, hibernation is a promising strategy to decrease cellular damage in a variety of fields, such as organ transplantation. Here, we explored the role of mitochondria herein, by comparing

  16. Hibernation Control Mechanism and Possible Applications to Humans

    Science.gov (United States)

    Kondo, N.

    Mammalian hibernation, characterized by the ability to survive temporarily at low body temperatures close to 0oC, has been reported to increase resistance to various lethal events such as low body temperature, severe ischemia, bacterial infection and irradiation, and to prolong the life span. The application of this physiological phenomenon to space life has been dreamed of. However, realization of this dream has been prevented by a poor understanding of the control mechanisms of hibernation. Recent findings of a novel and unique protein complex (HP) in the blood of chipmunks, a rodent hibernator, which is controlled by the endogenous circannual rhythm of hibernation, allowed new developments in understanding the molecular mechanism of hibernation and its physiological significance. From these studies, two hormones regulated by the brain were identified as promising candidate molecules controlling HP production in the liver, assuming that hibernation is controlled via the neuroendocrine system and regulated by the endogenous circannual rhythm in the brain. A circannual HP rhythm was observed in chipmunks maintaining euthermia under conditions of constant warmth, suggesting that the physiological control of hibernation progresses without a lowering of body temperature. Furthermore, the study of HP rhythm on longevity revealed that a circannual rhythm plays an essential role in the much longer life span of hibernators. The present progress in hibernation research may open a new pathway for manipulating a circannual rhythm controlling hibernation in humans. In the future, this will make it feasible to take advantage of hibernation in space life.

  17. Evaluation of cardiac function in active and hibernating grizzly bears.

    Science.gov (United States)

    Nelson, O Lynne; McEwen, Margaret-Mary; Robbins, Charles T; Felicetti, Laura; Christensen, William F

    2003-10-15

    To evaluate cardiac function parameters in a group of active and hibernating grizzly bears. Prospective study. 6 subadult grizzly bears. Indirect blood pressure, a 12-lead ECG, and a routine echocardiogram were obtained in each bear during the summer active phase and during hibernation. All measurements of myocardial contractility were significantly lower in all bears during hibernation, compared with the active period. Mean rate of circumferential left ventricular shortening, percentage fractional shortening, and percentage left ventricular ejection fraction were significantly lower in bears during hibernation, compared with the active period. Certain indices of diastolic function appeared to indicate enhanced ventricular compliance during the hibernation period. Mean mitral inflow ratio and isovolumic relaxation time were greater during hibernation. Heart rate was significantly lower for hibernating bears, and mean cardiac index was lower but not significantly different from cardiac index during the active phase. Contrary to results obtained in hibernating rodent species, cardiac index was not significantly correlated with heart rate. Cardiac function parameters in hibernating bears are opposite to the chronic bradycardic effects detected in nonhibernating species, likely because of intrinsic cardiac muscle adaptations during hibernation. Understanding mechanisms and responses of the myocardium during hibernation could yield insight into mechanisms of cardiac function regulation in various disease states in nonhibernating species.

  18. Antioxidant Defenses in the Brains of Bats during Hibernation.

    Directory of Open Access Journals (Sweden)

    Qiuyuan Yin

    Full Text Available Hibernation is a strategy used by some mammals to survive a cold winter. Small hibernating mammals, such as squirrels and hamsters, use species- and tissue-specific antioxidant defenses to cope with oxidative insults during hibernation. Little is known about antioxidant responses and their regulatory mechanisms in hibernating bats. We found that the total level of reactive oxygen species (ROS and reactive nitrogen species (RNS in the brain of each of the two distantly related hibernating bats M. ricketti and R. ferrumequinum at arousal was lower than that at torpid or active state. We also found that the levels of malondialdehyde (product of lipid peroxidation of the two hibernating species of bats were significantly lower than those of non-hibernating bats R. leschenaultia and C. sphinx. This observation suggests that bats maintain a basal level of ROS/RNS that does no harm to the brain during hibernation. Results of Western blotting showed that hibernating bats expressed higher amounts of antioxidant proteins than non-hibernating bats and that M. ricketti bats upregulated the expression of some enzymes to overcome oxidative stresses, such as superoxide dismutase, glutathione reductase, and catalase. In contrast, R. ferrumequinum bats maintained a relatively high level of superoxide dismutase 2, glutathione reductase, and thioredoxin-2 throughout the three different states of hibernation cycles. The levels of glutathione (GSH were higher in M. ricketti bats than in R. ferrumequinum bats and were significantly elevated in R. ferrumequinum bats after torpor. These data suggest that M. ricketti bats use mainly antioxidant enzymes and R. ferrumequinum bats rely on both enzymes and low molecular weight antioxidants (e.g., glutathione to avoid oxidative stresses during arousal. Furthermore, Nrf2 and FOXOs play major roles in the regulation of antioxidant defenses in the brains of bats during hibernation. Our study revealed strategies used by bats

  19. Seasonal oscillation of liver-derived hibernation protein complex in the central nervous system of non-hibernating mammals

    Science.gov (United States)

    Seldin, Marcus M.; Byerly, Mardi S.; Petersen, Pia S.; Swanson, Roy; Balkema-Buschmann, Anne; Groschup, Martin H.; Wong, G. William

    2014-01-01

    Mammalian hibernation elicits profound changes in whole-body physiology. The liver-derived hibernation protein (HP) complex, consisting of HP-20, HP-25 and HP-27, was shown to oscillate circannually, and this oscillation in the central nervous system (CNS) was suggested to play a role in hibernation. The HP complex has been found in hibernating chipmunks but not in related non-hibernating tree squirrels, leading to the suggestion that hibernation-specific genes may underlie the origin of hibernation. Here, we show that non-hibernating mammals express and regulate the conserved homologous HP complex in a seasonal manner, independent of hibernation. Comparative analyses of cow and chipmunk HPs revealed extensive biochemical and structural conservations. These include liver-specific expression, assembly of distinct heteromeric complexes that circulate in the blood and cerebrospinal fluid, and the striking seasonal oscillation of the HP levels in the blood and CNS. Central administration of recombinant HPs affected food intake in mice, without altering body temperature, physical activity levels or energy expenditure. Our results demonstrate that HP complex is not unique to the hibernators and suggest that the HP-regulated liver–brain circuit may couple seasonal changes in the environment to alterations in physiology. PMID:25079892

  20. Intrinsic circannual regulation of brown adipose tissue form and function in tune with hibernation.

    Science.gov (United States)

    Hindle, Allyson G; Martin, Sandra L

    2014-02-01

    Winter hibernators repeatedly cycle between cold torpor and rewarming supported by nonshivering thermogenesis in brown adipose tissue (BAT). In contrast, summer animals are homeotherms, undergoing reproduction, growth, and fattening. This life history confers variability to BAT recruitment and activity. To address the components underlying prewinter enhancement and winter activation, we interrogated the BAT proteome in 13-lined ground squirrels among three summer and five winter states. We also examined mixed physiology in fall and spring individuals to test for ambient temperature and seasonal effects, as well as the timing of seasonal transitions. BAT form and function differ circannually in these animals, as evidenced by morphology and proteome dynamics. This intrinsic pattern distinguished homeothermic groups and early vs. late winter hibernators. Homeothermic variation derived from postemergence delay in growth and substrate biosynthesis. The heterothermic proteome varied less despite extreme winter physiological shifts and was optimized to exploit lipids by enhanced fatty acid binding, β-oxidation, and mitochondrial protein translocation. Surprisingly, ambient temperature did not affect the BAT proteome during transition seasons; rather, the pronounced summer-winter shift preceded environmental changes and phenotypic progression. During fall transition, differential regulation of two fatty acid binding proteins provides further evidence of recruitment and separates proteomic preparation from successful hibernation. Abundance of FABP4 correlates with torpor bout length throughout the year, clarifying its potential function in hibernation. Metabolically active BAT is a target for treating human obesity and metabolic disorders. Understanding the hibernator's extreme and seasonally distinct recruitment and activation control strategies offers untapped potential to identify novel, therapeutically relevant regulatory pathways.

  1. Hibernal Emergence of Chironomidae in Ukraine

    Directory of Open Access Journals (Sweden)

    Viktor Baranov

    2013-12-01

    Full Text Available Twenty-seven species of Chironomidae were detected emerging in the Crimea during the period from December 2010 to March 2013. Twenty-three are Orthocladiinae and 4 are Chironominae (one Chironomini and three Tanytarsini species. Nine species are recorded for the first time in Crimea. At the genus-level the hibernal emergence in Crimea shows resemblance to the patterns reported for streams in Kansas.

  2. Telemetry experiments with a hibernating black bear

    Science.gov (United States)

    Craighead, J. J.; Varney, J. R.; Sumner, J. S.; Craighead, F. C., Jr.

    1972-01-01

    The objectives of this research were to develop and test telemetry equipment suitable for monitoring physiological parameters and activity of a hibernating bear in its den, to monitor this data and other environmental information with the Nimbus 3 IRLS data collection system, and to refine immobilizing, handling, and other techniques required in future work with wild bears under natural conditions. A temperature-telemetering transmitter was implanted in the abdominal cavity of a captive black bear and body temperature data was recorded continuously during a 3 month hibernation period. Body temperatures ranging between 37.5 and 31.8 C were observed. Body temperature and overall activity were influenced by disturbances and ambient den temperature. Nychthemeral temperature changes were not noticable. A load cell weight recording device was tested for determining weight loss during hibernation. Monitoring of data by satellite was not attempted. The implanted transmitter was removed and the bear was released with a radiolocation collar at the conclusion of the experiment.

  3. Stochastic population dynamics of a montane ground-dwelling squirrel.

    Science.gov (United States)

    Hostetler, Jeffrey A; Kneip, Eva; Van Vuren, Dirk H; Oli, Madan K

    2012-01-01

    Understanding the causes and consequences of population fluctuations is a central goal of ecology. We used demographic data from a long-term (1990-2008) study and matrix population models to investigate factors and processes influencing the dynamics and persistence of a golden-mantled ground squirrel (Callospermophilus lateralis) population, inhabiting a dynamic subalpine habitat in Colorado, USA. The overall deterministic population growth rate λ was 0.94±SE 0.05 but it varied widely over time, ranging from 0.45±0.09 in 2006 to 1.50±0.12 in 2003, and was below replacement (λbounce back from low densities and prevented extinction. These results suggest that dynamics and persistence of our study population are determined synergistically by density-dependence, stochastic forces, and immigration.

  4. Cardiac function adaptations in hibernating grizzly bears (Ursus arctos horribilis).

    Science.gov (United States)

    Nelson, O Lynne; Robbins, Charles T

    2010-03-01

    Research on the cardiovascular physiology of hibernating mammals may provide insight into evolutionary adaptations; however, anesthesia used to handle wild animals may affect the cardiovascular parameters of interest. To overcome these potential biases, we investigated the functional cardiac phenotype of the hibernating grizzly bear (Ursus arctos horribilis) during the active, transitional and hibernating phases over a 4 year period in conscious rather than anesthetized bears. The bears were captive born and serially studied from the age of 5 months to 4 years. Heart rate was significantly different from active (82.6 +/- 7.7 beats/min) to hibernating states (17.8 +/- 2.8 beats/min). There was no difference from the active to the hibernating state in diastolic and stroke volume parameters or in left atrial area. Left ventricular volume:mass was significantly increased during hibernation indicating decreased ventricular mass. Ejection fraction of the left ventricle was not different between active and hibernating states. In contrast, total left atrial emptying fraction was significantly reduced during hibernation (17.8 +/- 2.8%) as compared to the active state (40.8 +/- 1.9%). Reduced atrial chamber function was also supported by reduced atrial contraction blood flow velocities and atrial contraction ejection fraction during hibernation; 7.1 +/- 2.8% as compared to 20.7 +/- 3% during the active state. Changes in the diastolic cardiac filling cycle, especially atrial chamber contribution to ventricular filling, appear to be the most prominent macroscopic functional change during hibernation. Thus, we propose that these changes in atrial chamber function constitute a major adaptation during hibernation which allows the myocardium to conserve energy, avoid chamber dilation and remain healthy during a period of extremely low heart rates. These findings will aid in rational approaches to identifying underlying molecular mechanisms.

  5. Researches on the influence exerted by beehive type on bee family hibernation

    Directory of Open Access Journals (Sweden)

    Silvia Patruica

    2017-05-01

    Full Text Available This work presents the results of hibernation of bee colonies maintained in multi-storied beehives endowed with anti-varroa ground, made of wood and polystyrene Dadant. The experiments were carried out Banat’s University of Agricultural Sciences and Veterinary Medicine „King Michael the Ist” from Timişoara, Romania, between the 1st of November 2016 and 1st of March 2017. The biological material was represented by 20 Apis mellifera carpatica bee colonies, divided in two experimental variants, 10 colonies/batch, with similar power and same-age queens.  During the experiment, we observed the bee amount at the start of hibernation; the bee amount at the end of hibernation; the evolution of feed intake and losses caused by mortality. At the end of the experiment, we determined a bigger bee amount in the polystyrene Dadant beehives, significantly lower losses caused by mortality from a statistical point of view (p<0.001 and lower feed intake with 12.04% compared with the bee families maintained in the wooden multi-storied beehives.

  6. Energy homeostasis regulatory peptides in hibernating grizzly bears.

    Science.gov (United States)

    Gardi, János; Nelson, O Lynne; Robbins, Charles T; Szentirmai, Eva; Kapás, Levente; Krueger, James M

    2011-05-15

    Grizzly bears (Ursus arctos horribilis) are inactive for up to 6 months during hibernation. They undergo profound seasonal changes in food intake, body mass, and energy expenditure. The circa-annual regulation of metabolism is poorly understood. In this study, we measured plasma ghrelin, leptin, obestatin, and neuropeptide-Y (NPY) levels, hormones known to be involved in the regulation of energy homeostasis, in ten grizzly bears. Blood samples were collected during the active summer period, early hibernation and late hibernation. Plasma levels of leptin, obestatin, and NPY did not change between the active and the hibernation periods. Plasma total ghrelin and desacyl-ghrelin concentrations significantly decreased during the inactive winter period compared to summer levels. The elevated ghrelin levels may help enhance body mass during pre-hibernation, while the low plasma ghrelin concentrations during hibernation season may contribute to the maintenance of hypophagia, low energy utilization and behavioral inactivity. Our results suggest that ghrelin plays a potential role in the regulation of metabolic changes and energy homeostasis during hibernation in grizzly bears. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Proteomics approaches shed new light on hibernation physiology.

    Science.gov (United States)

    Grabek, Katharine R; Martin, Sandra L; Hindle, Allyson G

    2015-08-01

    The broad phylogenetic distribution and rapid phenotypic transitions of mammalian hibernators imply that hibernation is accomplished by differential expression of common genes. Traditional candidate gene approaches have thus far explained little of the molecular mechanisms underlying hibernation, likely due to (1) incomplete and imprecise sampling of a complex phenotype, and (2) the forming of hypotheses about which genes might be important based on studies of model organisms incapable of such dynamic physiology. Unbiased screening approaches, such as proteomics, offer an alternative means to discover the cellular underpinnings that permit successful hibernation and may reveal previously overlooked, important pathways. Here, we review the findings that have emerged from proteomics studies of hibernation. One striking feature is the stability of the proteome, especially across the extreme physiological shifts of torpor-arousal cycles during hibernation. This has led to subsequent investigations of the role of post-translational protein modifications in altering protein activity without energetically wasteful removal and rebuilding of protein pools. Another unexpected finding is the paucity of universal proteomic adjustments across organ systems in response to the extreme metabolic fluctuations despite the universality of their physiological challenges; rather each organ appears to respond in a unique, tissue-specific manner. Additional research is needed to extend and synthesize these results before it will be possible to address the whole body physiology of hibernation.

  8. Data logging of body temperatures provides precise information on phenology of reproductive events in a free-living arctic hibernator

    Science.gov (United States)

    Williams, C.T.; Sheriff, M.J.; Schmutz, J.A.; Kohl, F.; Toien, O.; Buck, C.L.; Barnes, B.M.

    2011-01-01

    Precise measures of phenology are critical to understanding how animals organize their annual cycles and how individuals and populations respond to climate-induced changes in physical and ecological stressors. We show that patterns of core body temperature (T b) can be used to precisely determine the timing of key seasonal events including hibernation, mating and parturition, and immergence and emergence from the hibernacula in free-living arctic ground squirrels (Urocitellus parryii). Using temperature loggers that recorded T b every 20 min for up to 18 months, we monitored core T b from three females that subsequently gave birth in captivity and from 66 female and 57 male ground squirrels free-living in the northern foothills of the Brooks Range Alaska. In addition, dates of emergence from hibernation were visually confirmed for four free-living male squirrels. Average T b in captive females decreased by 0.5–1.0°C during gestation and abruptly increased by 1–1.5°C on the day of parturition. In free-living females, similar shifts in T b were observed in 78% (n = 9) of yearlings and 94% (n = 31) of adults; females without the shift are assumed not to have given birth. Three of four ground squirrels for which dates of emergence from hibernation were visually confirmed did not exhibit obvious diurnal rhythms in T b until they first emerged onto the surface when T b patterns became diurnal. In free-living males undergoing reproductive maturation, this pre-emergence euthermic interval averaged 20.4 days (n = 56). T b-loggers represent a cost-effective and logistically feasible method to precisely investigate the phenology of reproduction and hibernation in ground squirrels.

  9. Delta opioid peptide (D-Ala 2, D-Leu 5) enkephalin: linking hibernation and neuroprotection.

    Science.gov (United States)

    Borlongan, Cesario V; Wang, Yun; Su, Tsung-Ping

    2004-09-01

    Hibernation is a potential protective strategy for the peripheral, as well as for the central nervous system. A protein factor termed hibernation induction trigger (HIT) was found to induce hibernation in summer-active ground squirrels. Purification of HIT yielded an 88-kD peptide that is enriched in winter hibernators. Partial sequence of the 88-kD protein indicates that it may be related to the inhibitor of metalloproteinase. Using opioid receptor antagonists to elucidate the mechanisms of HIT, it was found that HIT targeted the delta opioid receptors. Indeed, delta opioid (D-Ala 2, D-Leu 5) enkephalin (DADLE) was shown to induce hibernation. Specifically, HIT and DADLE were found to prolong survival of peripheral organs, such as the lung, the heart, liver, and kidney preserved en bloc or as a single preparation. In addition, DADLE has been recently demonstrated to promote survival of neurons in the central nervous system. Exposure to DADLE dose-dependently enhanced cell viability of cultured primary rat fetal dopaminergic cells. Subsequent transplantation of these DADLE-treated dopaminergic cells into the Parkinsonian rat brain resulted in a two-fold increase in surviving grafted cells. Interestingly, delivery of DADLE alone protected against dopaminergic depletion in a rodent model of Parkinson s disease. Similarly, DADLE blocked and reversed the dopaminergic terminal damage induced by methamphetamine (METH). Such neuroprotective effects of DADLE against METH neurotoxicity was accompanied by attenuation of mRNA expressions of a tumor necrosis factor p53 and an immediate early gene c-fos. In parallel to these beneficial effects of DADLE on the dopaminergic system, DADLE also ameliorated the neuronal damage induced by ischemia-reperfusion following a transient middle cerebral artery occlusion. In vitro replication of this ischemia cell death by serum-deprivation of PC12 cells revealed that DADLE exerted neuroprotection in a naltrexone-sensitive manner. These

  10. The involvement of mRNA processing factors TIA-1, TIAR, and PABP-1 during mammalian hibernation.

    Science.gov (United States)

    Tessier, Shannon N; Audas, Timothy E; Wu, Cheng-Wei; Lee, Stephen; Storey, Kenneth B

    2014-11-01

    Mammalian hibernators survive low body temperatures, ischemia-reperfusion, and restricted nutritional resources via global reductions in energy-expensive cellular processes and selective increases in stress pathways. Consequently, studies that analyze hibernation uncover mechanisms which balance metabolism and support survival by enhancing stress tolerance. We hypothesized processing factors that influence messenger ribonucleic acid (mRNA) maturation and translation may play significant roles in hibernation. We characterized the amino acid sequences of three RNA processing proteins (T cell intracellular antigen 1 (TIA-1), TIA1-related (TIAR), and poly(A)-binding proteins (PABP-1)) from thirteen-lined ground squirrels (Ictidomys tridecemlineatus), which all displayed a high degree of sequence identity with other mammals. Alternate Tia-1 and TiaR gene variants were found in the liver with higher expression of isoform b versus a in both cases. The localization of RNA-binding proteins to subnuclear structures was assessed by immunohistochemistry and confirmed by subcellular fractionation; TIA-1 was identified as a major component of subnuclear structures with up to a sevenfold increase in relative protein levels in the nucleus during hibernation. By contrast, there was no significant difference in the relative protein levels of TIARa/TIARb in the nucleus, and a decrease was observed for TIAR isoforms in cytoplasmic fractions of torpid animals. Finally, we used solubility tests to analyze the formation of reversible aggregates that are associated with TIA-1/R function during stress; a shift towards the soluble fraction (TIA-1a, TIA-1b) was observed during hibernation suggesting enhanced protein aggregation was not present during torpor. The present study identifies novel posttranscriptional regulatory mechanisms that may play a role in reducing translational rates and/or mRNA processing under unfavorable environmental conditions.

  11. Differences in mitochondrial function and morphology during cooling and rewarming between hibernator and non-hibernator derived kidney epithelial cells.

    Science.gov (United States)

    Hendriks, Koen D W; Lupi, Eleonora; Hardenberg, Maarten C; Hoogstra-Berends, Femke; Deelman, Leo E; Henning, Robert H

    2017-11-14

    Hibernators show superior resistance to ischemia and hypothermia, also outside the hibernation season. Therefore, hibernation is a promising strategy to decrease cellular damage in a variety of fields, such as organ transplantation. Here, we explored the role of mitochondria herein, by comparing epithelial cell lines from a hibernator (hamster kidney cells, HaK) and a non-hibernator (human embryonic kidney cells, HEK293) during cold preservation at 4 °C and rewarming. Cell survival (Neutral Red), ATP and MDA levels, mitochondrial membrane potential (MMP), mitochondrial morphology (using fluorescent probes) and metabolism (seahorse XF) were assessed. Hypothermia induced dispersion of the tubular mitochondrial network, a loss of MMP, increased oxygen radical (MDA) and decreased ATP production in HEK293. In contrast, HaK maintained MMP and ATP production without an increase in oxygen radicals during cooling and rewarming, resulting in superior cell survival compared to HEK293. Further, normothermic HaK showed a dispersed mitochondrial network and higher respiratory and glycolysis capacity compared to HEK293. Disclosing the mechanisms that hibernators use to counteract cell death in hypothermic and ischemic circumstances may help to eventually improve organ preservation in a variety of fields, including organ transplantation.

  12. Daily torpor and hibernation in birds and mammals

    Science.gov (United States)

    RUF, THOMAS; GEISER, FRITZ

    2014-01-01

    Many birds and mammals drastically reduce their energy expenditure during times of cold exposure, food shortage, or drought, by temporarily abandoning euthermia, i.e., the maintenance of high body temperatures. Traditionally, two different types of heterothermy, i.e., hypometabolic states associated with low body temperatures (torpor), have been distinguished: Daily torpor, which lasts less than 24 h and is accompanied by continued foraging, versus hibernation, with torpor bouts lasting consecutive days to several weeks in animals that usually do not forage but rely on energy stores, either food caches or body energy reserves. This classification of torpor types has been challenged however, suggesting that these phenotypes may merely represent the extremes in a continuum of traits. Here, we investigate whether variables of torpor in 214 species, 43 birds and 171 mammals form a continuum or a bimodal distribution. We use Gaussian-mixture cluster analysis as well as phylogenetically informed regressions to quantitatively assess the distinction between hibernation and daily torpor and to evaluate the impact of body mass and geographical distribution of species on torpor traits. Cluster analysis clearly confirmed the classical distinction between daily torpor and hibernation. Overall, heterothermic endotherms are small on average, but hibernators are significantly heavier than daily heterotherms and also are distributed at higher average latitudes (~35°) than daily heterotherms (~25°). Variables of torpor for an average 30-g heterotherm differed significantly between daily heterotherms and hibernators. Average maximum torpor bout duration was >30-fold longer, and mean torpor bout duration >25-fold longer in hibernators. Mean minimum body temperature differed by ~13°C, and the mean minimum torpor metabolic rate was ~35% of the BMR in daily heterotherms but only 6% of basal metabolic rate in hibernators. Consequently, our analysis strongly supports the view that

  13. Renal Sympathetic Denervation: Hibernation or Resurrection?

    Science.gov (United States)

    Papademetriou, Vasilios; Doumas, Michael; Tsioufis, Costas

    The most current versions of renal sympathetic denervation have been invented as minimally invasive approaches for the management of drug-resistant hypertension. The anatomy, physiology and pathophysiology of renal sympathetic innervation provide a strong background supporting an important role of the renal nerves in the regulation of blood pressure (BP) and volume. In addition, historical data with surgical sympathectomy and experimental data with surgical renal denervation indicate a beneficial effect on BP levels. Early clinical studies with transcatheter radiofrequency ablation demonstrated impressive BP reduction, accompanied by beneficial effects in target organ damage and other disease conditions characterized by sympathetic overactivity. However, the failure of the SYMPLICITY 3 trial to meet its primary efficacy end point raised a lot of concerns and put the field of renal denervation into hibernation. This review aims to translate basic research into clinical practice by presenting the anatomical and physiological basis for renal sympathetic denervation, critically discussing the past and present knowledge in this field, where we stand now, and also speculating about the future of the intervention and potential directions for research. © 2016 S. Karger AG, Basel.

  14. Physiological reactions to capture in hibernating brown bears.

    Science.gov (United States)

    Evans, Alina L; Singh, Navinder J; Fuchs, Boris; Blanc, Stéphane; Friebe, Andrea; Laske, Timothy G; Frobert, Ole; Swenson, Jon E; Arnemo, Jon M

    2016-01-01

    Human disturbance can affect animal life history and even population dynamics. However, the consequences of these disturbances are difficult to measure. This is especially true for hibernating animals, which are highly vulnerable to disturbance, because hibernation is a process of major physiological changes, involving conservation of energy during a resource-depleted time of year. During the winters of 2011-15, we captured 15 subadult brown bears ( Ursus arctos ) and recorded their body temperatures ( n  = 11) and heart rates ( n = 10) before, during and after capture using biologgers. We estimated the time for body temperature and heart rate to normalize after the capture event. We then evaluated the effect of the captures on the pattern and depth of hibernation and the day of den emergence by comparing the body temperature of captured bears with that of undisturbed subadult bears ( n  = 11). Both body temperature and heart rate increased during capture and returned to hibernation levels after 15-20 days. We showed that bears required 2-3 weeks to return to hibernation levels after winter captures, suggesting high metabolic costs during this period. There were also indications that the winter captures resulted in delayed den emergence.

  15. Alterations in the health of hibernating bats under pathogen pressure.

    Science.gov (United States)

    Bandouchova, Hana; Bartonička, Tomáš; Berkova, Hana; Brichta, Jiri; Kokurewicz, Tomasz; Kovacova, Veronika; Linhart, Petr; Piacek, Vladimir; Pikula, Jiri; Zahradníková, Alexandra; Zukal, Jan

    2018-04-17

    In underground hibernacula temperate northern hemisphere bats are exposed to Pseudogymnoascus destructans, the fungal agent of white-nose syndrome. While pathological and epidemiological data suggest that Palearctic bats tolerate this infection, we lack knowledge about bat health under pathogen pressure. Here we report blood profiles, along with body mass index (BMI), infection intensity and hibernation temperature, in greater mouse-eared bats (Myotis myotis). We sampled three European hibernacula that differ in geomorphology and microclimatic conditions. Skin lesion counts differed between contralateral wings of a bat, suggesting variable exposure to the fungus. Analysis of blood parameters suggests a threshold of ca. 300 skin lesions on both wings, combined with poor hibernation conditions, may distinguish healthy bats from those with homeostatic disruption. Physiological effects manifested as mild metabolic acidosis, decreased glucose and peripheral blood eosinophilia which were strongly locality-dependent. Hibernating bats displaying blood homeostasis disruption had 2 °C lower body surface temperatures. A shallow BMI loss slope with increasing pathogen load suggested a high degree of infection tolerance. European greater mouse-eared bats generally survive P. destructans invasion, despite some health deterioration at higher infection intensities (dependant on hibernation conditions). Conservation measures should minimise additional stressors to conserve constrained body reserves of bats during hibernation.

  16. Database Entity Persistence with Hibernate for the Network Connectivity Analysis Model

    Science.gov (United States)

    2014-04-01

    application developed in the Java language and using the Hibernate Application Programming Interface as the object-relational mapping library. The...13 9. An NCAM Entity Persistence – Java Coding Example 16 9.1 Hibernate Annotations...physical phenomenon problem to determine the overall link quality among the platforms specified for a NCAM run. Java , Netbeans, Hibernate , and the

  17. Modification of the radioprotective effect of hypoxic hypoxia by the artificial hibernation of the organism

    International Nuclear Information System (INIS)

    Ovakimov, V.G.; Yarmonenko, S.P.; Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Ehksperimental'noj i Klinicheskoj Onkologii)

    1975-01-01

    A significant weakening of the radioprotective effect of hypoxic hypoxia has been noted in the hibernated mice the resistance of which to acute oxygen deficiency is artificially hibernated (hypothermia under conditions of neuroplegia). The dose decrease factor is about 1.27 and 2.5 for hibernated and nonhibernated animals, respectively

  18. The Skeletal Biology of Hibernating Woodchucks (Marmota monax)

    Science.gov (United States)

    Doherty, Alison H.

    Long periods of inactivity in most mammals lead to significant bone loss that may not be completely recovered during an individual's lifetime regardless of future activity. Extended bouts of inactivity are the norm for hibernating mammals. It remains largely unknown, however, how these animals avoid adversely affecting bone, their quality, and ultimately survival given the challenges posed to their skeletons by inactivity and nutritional deprivation during hibernation. The primary goal of this project was to identify the physiological mechanisms regulating bone density, area and strength during extended periods of annual inactivity in hibernating woodchucks (Marmota monax). The overall hypothesis that bone integrity is unaffected by several months of inactivity during hibernation in woodchucks was tested across multiple levels of biological function. To gain a holistic assessment of seasonal bone integrity, the locomotor behavior and estimated stresses acting on woodchuck bones were investigated in conjunction with computed tomography scans and three-point bending tests to determine bone density, geometry, and mechanical properties of the long bones throughout the year. In addition, serum protein expression was examined to ascertain bone resorption and formation processes indicative of overall annual skeletal health. It was determined that woodchucks avoid significant changes in gait preference, but experience a decrease in bending stresses acting on distal limb bones following hibernation. Computed tomography scans indicated that bone mass, distribution, and trabecular structure are maintained in these animals throughout the year. Surprisingly, cortical density increased significantly posthibernation. Furthermore, three-point bending tests revealed that although less stiff, woodchuck femora were just as tough during the hibernation season, unlike brittle bones associated with osteoporosis. Finally, bone serum markers suggested a net maintenance of bone resorption

  19. Activity during natural hibernation in three species of Vespertilionid bats

    NARCIS (Netherlands)

    Daan, Serge

    1973-01-01

    1. Patterns of winter-activity in three species of bats (Myotis mystacinus, M. daubentoni, M. dasycneme) were studied in three hibernation quarters in The Netherlands. The methods of investigation involved: individual marking, automatic recording of intracave and extracave flights and assessment of

  20. Involvement of adrenal hormones in tissue respiration of sub-tropical hibernating and non-hibernating species of frogs.

    Science.gov (United States)

    Gupta, B B; Mahanta, A

    1997-03-01

    Effects of norepinephrine (NE), epinephrine (EP), corticosterone and cortisol were studied both in vivo and in vitro on the rate of oxygen consumption of tissues (liver, skeletal muscle and kidney) of sub-tropical Indian frogs Rana limnocharis (a hibernating species) and Rana cyanophlyctis (a non-hibernating species) exposed to natural climatic conditions during winter and summer/rainy seasons. Further, the effects of NE and EP were also studied in vitro in the presence of specific beta- and alpha-adrenergic antagonists (propranolol and prazosin). NE, EP and corticosterone, when administered in vivo or in vitro, significantly stimulated the respiratory rate of the tissues of both the species irrespective of the seasons/temperature. Results suggest that NE, EP and corticosterone are directly involved in regulation of the energy metabolism of both hibernating and non-hibernating species of sub-tropical frogs. The calorigenic action of NE and EP seems to be mediated by both beta- and alpha-adrenergic receptors. However, the temporal involvement of beta- and alpha-adrenergic receptors seems to be tissue-dependent.

  1. The Gut Microbiota Modulates Energy Metabolism in the Hibernating Brown Bear Ursus arctos.

    Science.gov (United States)

    Sommer, Felix; Ståhlman, Marcus; Ilkayeva, Olga; Arnemo, Jon M; Kindberg, Jonas; Josefsson, Johan; Newgard, Christopher B; Fröbert, Ole; Bäckhed, Fredrik

    2016-02-23

    Hibernation is an adaptation that helps many animals to conserve energy during food shortage in winter. Brown bears double their fat depots during summer and use these stored lipids during hibernation. Although bears seasonally become obese, they remain metabolically healthy. We analyzed the microbiota of free-ranging brown bears during their active phase and hibernation. Compared to the active phase, hibernation microbiota had reduced diversity, reduced levels of Firmicutes and Actinobacteria, and increased levels of Bacteroidetes. Several metabolites involved in lipid metabolism, including triglycerides, cholesterol, and bile acids, were also affected by hibernation. Transplantation of the bear microbiota from summer and winter to germ-free mice transferred some of the seasonal metabolic features and demonstrated that the summer microbiota promoted adiposity without impairing glucose tolerance, suggesting that seasonal variation in the microbiota may contribute to host energy metabolism in the hibernating brown bear. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Mammal survival at the Cretaceous–Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs

    OpenAIRE

    Lovegrove, Barry G.; Lobban, Kerileigh D.; Levesque, Danielle L.

    2014-01-01

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tro...

  3. Constructing collaboration and management platform with spring+ hibernate

    International Nuclear Information System (INIS)

    Zhang Hongmei; Ou Ge; Nie Jianyin; Song Liming; Chen Gang

    2007-01-01

    HCMP is the platform of collaboration and management for HXMT. The documents of HXMT project are the main context of HCMP. Besides the users of HXMT project, HCMP also serves other users. HCMP adopts the hierarchy Web structure to implement context release, documents approval, project management and portal website. HCMP provides the support of informatlization and standardization for HXMT project. This paper adopts Spring + Hibernate technique to construct the J2EE architecture, based on which HCMP is implemented. (authors)

  4. Cell and tissue structural modifications in hibernating dormice

    Directory of Open Access Journals (Sweden)

    Manuela Malatesta

    2005-06-01

    Full Text Available Abstract Tissues and cells of hibernating mammals undergo striking seasonal modifications of their activity through a quiescence-reactivation cycle. During winter, the temperature drastically decreases, the cell timing greatly slows down, the mitotic index sharply falls, DNA, RNA and protein synthesis are drastically reduced; however, upon arousal, all metabolic and physiological activities are quickly restored at the euthermic levels. The physiological, biochemical and behavioural aspects of hibernation have been extensively studied, but data on the morpho-functional relationships of cell and tissue components during the euthermia-hibernation-arousal cycle are rare. In this review, an overview of cell and tissue structural modifications so far reported in hibernating dormice is given and the possible role in the adaptation to the hypometabolic state as well as in the rapid resumption of activities upon arousal is discussed. Riassunto Modificazioni strutturali di cellule e tessuti in Gliridi ibernanti I tessuti e le cellule dei mammiferi ibernanti subiscono profonde modificazioni stagionali della loro attività attraverso un ciclo di quiescenza-riattivazione. Durante l'inverno, la temperatura corporea si abbassa a valori vicini a quelli ambientali, il ciclo cellulare rallenta, l'indice mitotico si riduce notevolmente e la sintesi di DNA, RNA e proteine è drasticamente ridotta. Tuttavia, al risveglio, tutte le attività metaboliche e fisiologiche sono rapidamente ristabilite ai livelli eutermici. Mentre gli aspetti fisiologici, biochimici e comportamentali dell'ibernazione sono stati ampiamenti studiati, i dati sulle relazioni morfo-funzionali dei componenti cellulari e tessutali durante il ciclo eutermia-ibernazione-risveglio sono piuttosto rari. In questo articolo vengono riassunte le attuali conoscenze sulle modificazioni strutturali di cellule e tessuti nei Gliridi ibernanti e viene discusso

  5. Changes during hibernation in different phospholipid and free and esterified cholesterol serum levels in black bears

    Science.gov (United States)

    Chauhan, V.; Sheikh, A.; Chauhan, A.; Tsiouris, J.; Malik, M.; Vaughan, M.

    2002-01-01

    During hibernation, fat is known to be the preferred source of energy. A detailed analysis of different phospholipids, as well as free and esterified cholesterol, was conducted to investigate lipid abnormalities during hibernation. The levels of total phospholipids and total cholesterol in the serum of black bears were found to increase significantly in hibernation as compared with the active state. Both free and esterified cholesterol were increased in the hibernating state in comparison with the active state (P biologie mole??culaire. All rights reserved.

  6. Immunoelectron microscopic characterization of nucleolus-associated domains during hibernation.

    Science.gov (United States)

    Malatesta, Manuela; Zancanaro, Carlo; Biggiogera, Marco

    2011-01-01

    The nucleolus represents a highly dynamic nuclear compartment involved in multiple functions and able to promptly respond to variations of metabolic needs. In the hibernator dormouse, which drastically modifies its metabolic activity during the seasonal cycle, the nucleolus undergoes structural and molecular changes during the torpor bouts; in particular, it shows many nucleoplasmic invaginations containing weakly contrasted areas of unknown nature. To analyze the molecular composition of these nucleolus-associated domains (NADs) and to understand their functional significance, the fine nucleolar composition has been investigated by means of ultrastructural immunocytochemistry in different tissues of euthermic, hibernating, and arousing hazel dormice (Muscardinus avellanarius): in particular, the intranucleolar location of several protein factors involved in the transcription and processing of either pre-rRNA or pre-mRNA has been considered. NADs proved to form during hibernation and disappear upon arousal and were found to contain m₃-G-capped snRNAs, snRNPs, hnRNPs, and the survival motor neuron protein; they were, on the contrary, devoid of the nucleolar factors tested (polymerase I, fibrillarin, nucleolin, and the ribosomal phosphoproteins P₀, P₁, and P₂). We hypothesize that NADs may represent a transient storage site for those molecules involved in the pre-mRNA splicing, which usually transit through the nucleolus; upon arousal, this would facilitate the resumption of RNA maturation by promoting the rapid reactivation of the molecular trafficking from the nucleolus. © 2010 Wiley-Liss, Inc.

  7. delta-Opioid-induced pharmacologic myocardial hibernation during cardiopulmonary resuscitation.

    Science.gov (United States)

    Fang, Xiangshao; Tang, Wanchun; Sun, Shijie; Weil, Max Harry

    2006-12-01

    Cardiac arrest and cardiopulmonary resuscitation is an event of global myocardial ischemia and reperfusion, which is associated with severe postresuscitation myocardial dysfunction and fatal outcome. Evidence has demonstrated that mammalian hibernation is triggered by cyclic variation of a delta-opiate-like compound in endogenous serum, during which the myocardial metabolism is dramatically reduced and the myocardium tolerates the stress of ischemia and reperfusion without overt ischemic and reperfusion injury. Previous investigations also proved that the delta-opioid agonist elicited the cardioprotection in a model of regional ischemic intact heart or myocyte. Accordingly, we were prompted to search for an alternative intervention of pharmacologically induced myocardial hibernation that would result in rapid reductions of myocardial metabolism and therefore minimize the myocardial ischemic and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation. Prospective, controlled laboratory study. University-affiliated research laboratory. In the series of studies performed in the established rat and pig model of cardiac arrest and cardiopulmonary resuscitation, the delta-opioid receptor agonist, pentazocine, was administered during ventricular fibrillation. : The myocardial metabolism reflected by the concentration of lactate, or myocardial tissue PCO2 and PO2, is dramatically reduced during cardiac arrest and cardiopulmonary resuscitation. These are associated with less severe postresuscitation myocardial dysfunction and longer duration of postresuscitation survival. delta-Opioid-induced pharmacologic myocardial hibernation is an option to minimize the myocardial ischemia and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation.

  8. Hibernation metabolism of mammalia (marmota menzeri kaschk) and reptiles (testudo horsfieldi gray)

    International Nuclear Information System (INIS)

    Gibarova, S.

    2001-01-01

    It has been revealed that, upon hypnosis resulting from the winter hibernation, the content of glucose in the blood of mammals (Marmota menzberi Kaschk.) and reptiles( Testudo horsfieldi Gray) has decreased whereas the components of the lipid exchange and the activity of the enzyme alanin and aspartate transaminase have increased, the changes observed being more pronounced in the tortoise than in marmote. On a level of the intact organism in vitro, over the 30 fold and 100 fold decrease of gas oxygen exchange takes place in marmots and tortoises, respectively upon the body temperature decreases as low as 4-5 degree Celsius as a result of winter hibernation. At a mitochondrial level, a decrease in the bio energetic parameters by 4-6 times with a prevailing inhibition of succinate oxidation was recorded in marmots and by 3 times in tortoises in the state of hypo biosis, which witnesses deep restructuring of the enzymatic metabolic characteristics of the tissue energetics under these conditions. More significant inhibition of the respiratory activity in the mitochondria of the liver, kidney and heart against the other organs was reported in ground squirrel when in the state of natural winter sleeping. Upon the temperature drop in vitro by 37,25,16 degree Celsius the respiratory activity of the liver mitochondria of active rodents was recorded to decrease to a significantly smaller degrees ( by 4 times ) than in those of the reptiles ( by 12 times ), thus witnessing a smaller temperature dependence of the subcellular energetics of the warm blooded animals and the necessity of functioning of special mechanism decreasing mitochondrial respiration in this group as compared with the cold blooded animals while in hypo biosis

  9. Multistate proteomics analysis reveals novel strategies used by a hibernator to precondition the heart and conserve ATP for winter heterothermy

    Science.gov (United States)

    Grabek, Katharine R.; Karimpour-Fard, Anis; Epperson, L. Elaine; Hindle, Allyson; Hunter, Lawrence E.

    2011-01-01

    The hibernator's heart functions continuously and avoids damage across the wide temperature range of winter heterothermy. To define the molecular basis of this phenotype, we quantified proteomic changes in the 13-lined ground squirrel heart among eight distinct physiological states encompassing the hibernator's year. Unsupervised clustering revealed a prominent seasonal separation between the summer homeotherms and winter heterotherms, whereas within-season state separation was limited. Further, animals torpid in the fall were intermediate to summer and winter, consistent with the transitional nature of this phase. A seasonal analysis revealed that the relative abundances of protein spots were mainly winter-increased. The winter-elevated proteins were involved in fatty acid catabolism and protein folding, whereas the winter-depleted proteins included those that degrade branched-chain amino acids. To identify further state-dependent changes, protein spots were re-evaluated with respect to specific physiological state, confirming the predominance of seasonal differences. Additionally, chaperone and heat shock proteins increased in winter, including HSPA4, HSPB6, and HSP90AB1, which have known roles in protecting against ischemia-reperfusion injury and apoptosis. The most significant and greatest fold change observed was a disappearance of phospho-cofilin 2 at low body temperature, likely a strategy to preserve ATP. The robust summer-to-winter seasonal proteomic shift implies that a winter-protected state is orchestrated before prolonged torpor ensues. Additionally, the general preservation of the proteome during winter hibernation and an increase of stress response proteins, together with dephosphorylation of cofilin 2, highlight the importance of ATP-conserving mechanisms for winter cardioprotection. PMID:21914784

  10. Serum immune-related proteins are differentially expressed during hibernation in the American black bear.

    Directory of Open Access Journals (Sweden)

    Brian A Chow

    Full Text Available Hibernation is an adaptation to conserve energy in the face of extreme environmental conditions and low food availability that has risen in several animal phyla. This phenomenon is characterized by reduced metabolic rate (∼25% of the active basal metabolic rate in hibernating bears and energy demand, while other physiological adjustments are far from clear. The profiling of the serum proteome of the American black bear (Ursus americanus may reveal specific proteins that are differentially modulated by hibernation, and provide insight into the remarkable physiological adaptations that characterize ursid hibernation. In this study, we used differential gel electrophoresis (DIGE analysis, liquid chromatography coupled to tandem mass spectrometry, and subsequent MASCOT analysis of the mass spectra to identify candidate proteins that are differentially expressed during hibernation in captive black bears. Seventy serum proteins were identified as changing by ±1.5 fold or more, out of which 34 proteins increased expression during hibernation. The majority of identified proteins are involved in immune system processes. These included α2-macroglobulin, complement components C1s and C4, immunoglobulin μ and J chains, clusterin, haptoglobin, C4b binding protein, kininogen 1, α2-HS-glycoprotein, and apoplipoproteins A-I and A-IV. Differential expression of a subset of these proteins identified by proteomic analysis was also confirmed by immunodetection. We propose that the observed serum protein changes contribute to the maintenance of the hibernation phenotype and health, including increased capacities for bone maintenance and wound healing during hibernation in bears.

  11. The Gut Microbiota Modulates Energy Metabolism in the Hibernating Brown Bear Ursus arctos

    DEFF Research Database (Denmark)

    Sommer, Felix; Ståhlman, Marcus; Ilkayeva, Olga

    2016-01-01

    the microbiota of free-ranging brown bears during their active phase and hibernation. Compared to the active phase, hibernation microbiota had reduced diversity, reduced levels of Firmicutes and Actinobacteria, and increased levels of Bacteroidetes. Several metabolites involved in lipid metabolism, including...

  12. Titin isoform switching is a major cardiac adaptive response in hibernating grizzly bears.

    Science.gov (United States)

    Nelson, O Lynne; Robbins, Charles T; Wu, Yiming; Granzier, Henk

    2008-07-01

    The hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. Here we studied how hibernating grizzly bears (Ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. We evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and hibernating period. Because both collagen and titin are involved in altering diastolic function, we investigated both in the myocardium of active and hibernating grizzly bears. Heart rates were reduced from 84 beats/min in active bears to 19 beats/min in hibernating bears. Diastolic volume, stroke volume, and left ventricular ejection fraction were not different. However, left ventricular muscle mass was significantly lower (300 +/- 12 compared with 402 +/- 14 g; P = 0.003) in the hibernating bears, and as a result the diastolic volume-to-left ventricular muscle mass ratio was significantly greater. Early ventricular filling deceleration times (106.4 +/- 14 compared with 143.2 +/- 20 ms; P = 0.002) were shorter during hibernation, suggesting increased ventricular stiffness. Restrictive pulmonary venous flow patterns supported this conclusion. Collagen type I and III comparisons did not reveal differences between the two groups of bears. In contrast, the expression of titin was altered by a significant upregulation of the stiffer N2B isoform at the expense of the more compliant N2BA isoform. The mean ratio of N2BA to N2B titin was 0.73 +/- 0.07 in the active bears and decreased to 0.42 +/- 0.03 (P = 0.006) in the hibernating bears. The upregulation of stiff N2B cardiac titin is a likely explanation for the increased ventricular stiffness that was revealed by echocardiography, and we propose that it plays a role in preventing chamber dilation in hibernating grizzly bears. Thus our work identified changes in the alternative splicing of cardiac titin as a major adaptive response in hibernating grizzly

  13. Metabolic changes associated with the long winter fast dominate the liver proteome in 13-lined ground squirrels.

    Science.gov (United States)

    Hindle, Allyson G; Grabek, Katharine R; Epperson, L Elaine; Karimpour-Fard, Anis; Martin, Sandra L

    2014-05-15

    Small-bodied hibernators partition the year between active homeothermy and hibernating heterothermy accompanied by fasting. To define molecular events underlying hibernation that are both dependent and independent of fasting, we analyzed the liver proteome among two active and four hibernation states in 13-lined ground squirrels. We also examined fall animals transitioning between fed homeothermy and fasting heterothermy. Significantly enriched pathways differing between activity and hibernation were biased toward metabolic enzymes, concordant with the fuel shifts accompanying fasting physiology. Although metabolic reprogramming to support fasting dominated these data, arousing (rewarming) animals had the most distinct proteome among the hibernation states. Instead of a dominant metabolic enzyme signature, torpor-arousal cycles featured differences in plasma proteins and intracellular membrane traffic and its regulation. Phosphorylated NSFL1C, a membrane regulator, exhibited this torpor-arousal cycle pattern; its role in autophagosome formation may promote utilization of local substrates upon metabolic reactivation in arousal. Fall animals transitioning to hibernation lagged in their proteomic adjustment, indicating that the liver is more responsive than preparatory to the metabolic reprogramming of hibernation. Specifically, torpor use had little impact on the fall liver proteome, consistent with a dominant role of nutritional status. In contrast to our prediction of reprogramming the transition between activity and hibernation by gene expression and then within-hibernation transitions by posttranslational modification (PTM), we found extremely limited evidence of reversible PTMs within torpor-arousal cycles. Rather, acetylation contributed to seasonal differences, being highest in winter (specifically in torpor), consistent with fasting physiology and decreased abundance of the mitochondrial deacetylase, SIRT3. Copyright © 2014 the American Physiological Society.

  14. Metabolic changes associated with the long winter fast dominate the liver proteome in 13-lined ground squirrels

    Science.gov (United States)

    Hindle, Allyson G.; Grabek, Katharine R.; Epperson, L. Elaine; Karimpour-Fard, Anis

    2014-01-01

    Small-bodied hibernators partition the year between active homeothermy and hibernating heterothermy accompanied by fasting. To define molecular events underlying hibernation that are both dependent and independent of fasting, we analyzed the liver proteome among two active and four hibernation states in 13-lined ground squirrels. We also examined fall animals transitioning between fed homeothermy and fasting heterothermy. Significantly enriched pathways differing between activity and hibernation were biased toward metabolic enzymes, concordant with the fuel shifts accompanying fasting physiology. Although metabolic reprogramming to support fasting dominated these data, arousing (rewarming) animals had the most distinct proteome among the hibernation states. Instead of a dominant metabolic enzyme signature, torpor-arousal cycles featured differences in plasma proteins and intracellular membrane traffic and its regulation. Phosphorylated NSFL1C, a membrane regulator, exhibited this torpor-arousal cycle pattern; its role in autophagosome formation may promote utilization of local substrates upon metabolic reactivation in arousal. Fall animals transitioning to hibernation lagged in their proteomic adjustment, indicating that the liver is more responsive than preparatory to the metabolic reprogramming of hibernation. Specifically, torpor use had little impact on the fall liver proteome, consistent with a dominant role of nutritional status. In contrast to our prediction of reprogramming the transition between activity and hibernation by gene expression and then within-hibernation transitions by posttranslational modification (PTM), we found extremely limited evidence of reversible PTMs within torpor-arousal cycles. Rather, acetylation contributed to seasonal differences, being highest in winter (specifically in torpor), consistent with fasting physiology and decreased abundance of the mitochondrial deacetylase, SIRT3. PMID:24642758

  15. Structure of Vibrio cholerae ribosome hibernation promoting factor

    International Nuclear Information System (INIS)

    De Bari, Heather; Berry, Edward A.

    2013-01-01

    The X-ray crystal structure of ribosome hibernation promoting factor from V. cholerae has been determined at 2.0 Å resolution. The crystal was phased by two-wavelength MAD using cocrystallized cobalt. The X-ray crystal structure of ribosome hibernation promoting factor (HPF) from Vibrio cholerae is presented at 2.0 Å resolution. The crystal was phased by two-wavelength MAD using cocrystallized cobalt. The asymmetric unit contained two molecules of HPF linked by four Co atoms. The metal-binding sites observed in the crystal are probably not related to biological function. The structure of HPF has a typical β–α–β–β–β–α fold consistent with previous structures of YfiA and HPF from Escherichia coli. Comparison of the new structure with that of HPF from E. coli bound to the Thermus thermophilus ribosome [Polikanov et al. (2012 ▶), Science, 336, 915–918] shows that no significant structural changes are induced in HPF by binding

  16. Neuronal plasticity in the hedgehog supraoptic nucleus during hibernation.

    Science.gov (United States)

    Sanchez-Toscano, F; Caminero, A A; Machin, C; Abella, G

    1989-01-01

    The purpose of the present study was to identify processes of plasticity in the receptive field of neurosecretory neurons of the supraoptic nucleus during hibernation in the hedgehog, in order to correlate them with the increased neurosecretory activity observed in this nucleus during this annual period. Using the Rapid Golgi method, a quantitative study was conducted in the receptive field of bipolar and multipolar neurons (the main components of the nucleus). Results indicate a generalized increase in the following characteristics: (1) number of dendritic spines per millimeter along the dendritic shafts; (2) degree of branching in the dendritic field; and (3) dendritic density around the neuronal soma. These data demonstrate modification of the dendritic field in the supraoptic nucleus during hibernation, a change undoubtedly related to functional conditions. Since the observed changes affect structures such as dendritic spines which are directly related to the arrival of neural afferences, the discussion is centered on the types of stimuli which may be responsible for the observed processes.

  17. Elevated expression of protein biosynthesis genes in liver and muscle of hibernating black bears (Ursus americanus).

    Science.gov (United States)

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Øivind; Stewart, Nathan C; Gracey, Andrew Y; Chang, Celia; Qin, Shizhen; Pertea, Geo; Quackenbush, John; Showe, Louise C; Showe, Michael K; Boyer, Bert B; Barnes, Brian M

    2009-04-10

    We conducted a large-scale gene expression screen using the 3,200 cDNA probe microarray developed specifically for Ursus americanus to detect expression differences in liver and skeletal muscle that occur during winter hibernation compared with animals sampled during summer. The expression of 12 genes, including RNA binding protein motif 3 (Rbm3), that are mostly involved in protein biosynthesis, was induced during hibernation in both liver and muscle. The Gene Ontology and Gene Set Enrichment analysis consistently showed a highly significant enrichment of the protein biosynthesis category by overexpressed genes in both liver and skeletal muscle during hibernation. Coordinated induction in transcriptional level of genes involved in protein biosynthesis is a distinctive feature of the transcriptome in hibernating black bears. This finding implies induction of translation and suggests an adaptive mechanism that contributes to a unique ability to reduce muscle atrophy over prolonged periods of immobility during hibernation. Comparing expression profiles in bears to small mammalian hibernators shows a general trend during hibernation of transcriptional changes that include induction of genes involved in lipid metabolism and carbohydrate synthesis as well as depression of genes involved in the urea cycle and detoxification function in liver.

  18. Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus).

    Science.gov (United States)

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Øivind; Stewart, Nathan C; Chang, Celia; Wang, Haifang; Yan, Jun; Showe, Louise C; Showe, Michael K; Barnes, Brian M

    2011-03-31

    Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.

  19. Immune responses in hibernating little brown myotis (Myotis lucifugus) with white-nose syndrome.

    Science.gov (United States)

    Lilley, T M; Prokkola, J M; Johnson, J S; Rogers, E J; Gronsky, S; Kurta, A; Reeder, D M; Field, K A

    2017-02-08

    White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans ( Pd ), the psychrophilic fungus responsible for WNS, prospers in the winter habitat of many hibernating bat species. The immune response that Pd elicits in bats is not yet fully understood; antibodies are produced in response to infection by Pd , but they may not be protective and indeed may be harmful. To understand how bats respond to infection during hibernation, we studied the effect of Pd inoculation on the survival and gene expression of captive hibernating Myotis lucifugus with varying pre-hibernation antifungal antibody titres. We investigated gene expression through the transcription of selected cytokine genes ( Il6 , Il17a , Il1b , Il4 and Ifng ) associated with inflammatory, Th1, Th2 and Th17 immune responses in wing tissue and lymph nodes. We found no difference in survival between bats with low and high anti- Pd titres, although anti- Pd antibody production during hibernation differed significantly between infected and uninfected bats. Transcription of Il6 and Il17a was higher in the lymph nodes of infected bats compared with uninfected bats. Increased transcription of these cytokines in the lymph node suggests that a pro-inflammatory immune response to WNS is not restricted to infected tissues and occurs during hibernation. The resulting Th17 response may be protective in euthermic bats, but because it may disrupt torpor, it could be detrimental during hibernation. © 2017 The Author(s).

  20. Suppressed bone remodeling in black bears conserves energy and bone mass during hibernation.

    Science.gov (United States)

    McGee-Lawrence, Meghan; Buckendahl, Patricia; Carpenter, Caren; Henriksen, Kim; Vaughan, Michael; Donahue, Seth

    2015-07-01

    Decreased physical activity in mammals increases bone turnover and uncouples bone formation from bone resorption, leading to hypercalcemia, hypercalcuria, bone loss and increased fracture risk. Black bears, however, are physically inactive for up to 6 months annually during hibernation without losing cortical or trabecular bone mass. Bears have been shown to preserve trabecular bone volume and architectural parameters and cortical bone strength, porosity and geometrical properties during hibernation. The mechanisms that prevent disuse osteoporosis in bears are unclear as previous studies using histological and serum markers of bone remodeling show conflicting results. However, previous studies used serum markers of bone remodeling that are known to accumulate with decreased renal function, which bears have during hibernation. Therefore, we measured serum bone remodeling markers (BSALP and TRACP) that do not accumulate with decreased renal function, in addition to the concentrations of serum calcium and hormones involved in regulating bone remodeling in hibernating and active bears. Bone resorption and formation markers were decreased during hibernation compared with when bears were physically active, and these findings were supported by histomorphometric analyses of bone biopsies. The serum concentration of cocaine and amphetamine regulated transcript (CART), a hormone known to reduce bone resorption, was 15-fold higher during hibernation. Serum calcium concentration was unchanged between hibernation and non-hibernation seasons. Suppressed and balanced bone resorption and formation in hibernating bears contributes to energy conservation, eucalcemia and the preservation of bone mass and strength, allowing bears to survive prolonged periods of extreme environmental conditions, nutritional deprivation and anuria. © 2015. Published by The Company of Biologists Ltd.

  1. The influence of sex and diet on the characteristics of hibernation in Syrian hamsters.

    Science.gov (United States)

    Trefna, Marie; Goris, Maaike; Thissen, Cynthia M C; Reitsema, Vera A; Bruintjes, Jojanneke J; de Vrij, Edwin L; Bouma, Hjalmar R; Boerema, Ate S; Henning, Robert H

    2017-07-01

    Research on deep hibernators almost exclusively uses species captured from the wild or from local breeding. An exception is Syrian hamster (Mesocricetus auratus), the only standard laboratory animal showing deep hibernation. In deep hibernators, several factors influence hibernation quality, including body mass, sex and diet. We examined hibernation quality in commercially obtained Syrian hamsters in relation to body mass, sex and a diet enriched in polyunsaturated fatty acids. Animals (M/F:30/30, 12 weeks of age) were obtained from Harlan (IN, USA) and individually housed at 21 °C and L:D 14:10 until 20 weeks of age, followed by L:D 8:16 until 27 weeks. Then conditions were changed to 5 °C and L:D 0:24 for 9 weeks to induce hibernation. Movement was continuously monitored with passive infrared detectors. Hamsters were randomized to control diet or a diet 3× enriched in linoleic acid from 16 weeks of age. Hamsters showed a high rate of premature death (n = 24, 40%), both in animals that did and did not initiate torpor, which was unrelated to body weight, sex and diet. Time to death (31.7 ± 3.1 days, n = 12) or time to first torpor bout (36.6 ± 1.6 days, n = 12) was similar in prematurely deceased hamsters. Timing of induction of hibernation and duration of torpor and arousal was unaffected by body weight, sex or diet. Thus, commercially obtained Syrian hamsters subjected to winter conditions showed poor survival, irrespective of body weight, sex and diet. These factors also did not affect hibernation parameters. Possibly, long-term commercial breeding from a confined genetic background has selected against the hibernation trait.

  2. Oxidation of linoleic and palmitic acid in pre-hibernating and hibernating common noctule bats revealed by 13C breath testing.

    Science.gov (United States)

    Rosner, Elisabeth; Voigt, Christian C

    2018-02-19

    Mammals fuel hibernation by oxidizing saturated and unsaturated fatty acids from triacylglycerols in adipocytes, yet the relative importance of these two categories as an oxidative fuel may change during hibernation. We studied the selective use of fatty acids as an oxidative fuel in noctule bats ( Nyctalus noctula ). Pre-hibernating noctule bats that were fed 13 C-enriched linoleic acid (LA) showed 12 times higher tracer oxidation rates compared with conspecifics fed 13 C-enriched palmitic acid (PA). After this experiment, we supplemented the diet of bats with the same fatty acids on five subsequent days to enrich their fat depots with the respective tracer. We then compared the excess 13 C enrichment (excess atom percentage, APE) in breath of bats for torpor and arousal events during early and late hibernation. We observed higher APE values in breath of bats fed 13 C-enriched LA than in bats fed 13 C-enriched PA for both states (torpor and arousal), and also for both periods. Thus, hibernating bats selectively oxidized endogenous LA instead of PA, probably because of faster transportation rates of polyunsaturated fatty acids compared with saturated fatty acids. We did not observe changes in APE values in the breath of torpid animals between early and late hibernation. Skin temperature of torpid animals increased by 0.7°C between early and late hibernation in bats fed PA, whereas it decreased by -0.8°C in bats fed LA, highlighting that endogenous LA may fulfil two functions when available in excess: serving as an oxidative fuel and supporting cell membrane functionality. © 2018. Published by The Company of Biologists Ltd.

  3. Incidence of stunned, hibernating and scarred myocardium in ischaemic cardiomyopathy

    International Nuclear Information System (INIS)

    Hernandez-Pampaloni, Miguel; Morita, Koichi; Dutka, David P.; Camici, Paolo G.; Bax, Jeroen J.

    2005-01-01

    Different criteria to identify residual viability in chronically dysfunctioning myocardium in patients with coronary artery disease (CAD) can be derived by the combined assessment of myocardial blood flow (MBF) and glucose utilisation (MRG) using positron emission tomography (PET). The aim of this study was to evaluate, in a large number of patients, the prevalence of these different patterns by purely quantitative means. One hundred and sixteen consecutive patients with ischaemic cardiomyopathy (LVEF ≤40%) underwent resting 2D echocardiography to assess regional contractile function (16-segment model). PET with 15 O-labelled water (H 2 15 O) and 18 F-fluorodeoxyglucose (FDG) was used to quantify MBF and MRG during hyperinsulinaemic euglycaemic clamp. Dysfunctional segments with normal MBF (≥0.6 ml min -1 g -1 ) were classified as stunned, and segments with reduced MBF ( -1 g -1 ) as hibernating if MRG was ≥0.25 μmol min -1 g -1 . Segments with reduced MBF and MRG -1 g -1 were classified as transmural scars and segments with reduced MBF and MRG between 0.20 and 0.25 μmol min -1 g -1 as non-transmural scars. Eight hundred and thirty-four (46%) segments were dysfunctional. Of these, 601 (72%) were chronically stunned, with 368 (61%) having normal MRG (0.47±0.20 μmol min -1 g -1 ) and 233 (39%) reduced MRG (0.16±0.05 μmol min -1 g -1 ). Seventy-four (9%) segments with reduced MBF had preserved MRG (0.40±0.18 μmol min -1 g -1 ) and were classified as hibernating myocardium. In addition, 15% of segments were classified as transmural and 4% as non-transmural scar. The mean MBF was highest in stunned myocardium (0.95±0.32 ml min -1 g -1 ), intermediate in hibernating myocardium and non-transmural scars (0.47±0.09 ml min -1 g -1 and 0.48±0.08 ml min -1 g -1 , respectively), and lowest in transmural scars (0.40±0.14 ml min -1 g -1 , P -1 g -1 vs 0.46±0.20 μmol min -1 g -1 , NS), and lowest in stunned myocardium with reduced MRG and transmural scars

  4. Great tits search for, capture, kill and eat hibernating bats

    Science.gov (United States)

    Estók, Péter; Zsebők, Sándor; Siemers, Björn M.

    2010-01-01

    Ecological pressure paired with opportunism can lead to surprising innovations in animal behaviour. Here, we report predation of great tits (Parus major) on hibernating pipistrelle bats (Pipistrellus pipistrellus) at a Hungarian cave. Over two winters, we directly observed 18 predation events. The tits specifically and systematically searched for and killed bats for food. A substantial decrease in predation on bats after experimental provisioning of food to the tits further supports the hypothesis that bat-killing serves a foraging purpose in times of food scarcity. We finally conducted a playback experiment to test whether tits would eavesdrop on calls of awakening bats to find them in rock crevices. The tits could clearly hear the calls and were attracted to the loudspeaker. Records for tit predation on bats at this cave now span more than ten years and thus raise the question of whether cultural transmission plays a role for the spread of this foraging innovation. PMID:19740892

  5. Hibernation in an antarctic fish: on ice for winter.

    Directory of Open Access Journals (Sweden)

    Hamish A Campbell

    Full Text Available Active metabolic suppression in anticipation of winter conditions has been demonstrated in species of mammals, birds, reptiles and amphibians, but not fish. This is because the reduction in metabolic rate in fish is directly proportional to the decrease in water temperature and they appear to be incapable of further suppressing their metabolic rate independently of temperature. However, the Antarctic fish (Notothenia coriiceps is unusual because it undergoes winter metabolic suppression irrespective of water temperature. We assessed the seasonal ecological strategy by monitoring swimming activity, growth, feeding and heart rate (f(H in N. coriiceps as they free-ranged within sub-zero waters. The metabolic rate of wild fish was extrapolated from f(H recordings, from oxygen consumption calibrations established in the laboratory prior to fish release. Throughout the summer months N. coriiceps spent a considerable proportion of its time foraging, resulting in a growth rate (G(w of 0.18 +/- 0.2% day(-1. In contrast, during winter much of the time was spent sedentary within a refuge and fish showed a net loss in G(w (-0.05 +/- 0.05% day(-1. Whilst inactive during winter, N. coriiceps displayed a very low f(H, reduced sensory and motor capabilities, and standard metabolic rate was one third lower than in summer. In a similar manner to other hibernating species, dormancy was interrupted with periodic arousals. These arousals, which lasted a few hours, occurred every 4-12 days. During arousal activity, f(H and metabolism increased to summer levels. This endogenous suppression and activation of metabolic processes, independent of body temperature, demonstrates that N. coriiceps were effectively 'putting themselves on ice' during winter months until food resources improved. This study demonstrates that at least some fish species can enter a dormant state similar to hibernation that is not temperature driven and presumably provides seasonal energetic

  6. Brain inflammatory cytokines and microglia morphology changes throughout hibernation phases in Syrian hamster

    NARCIS (Netherlands)

    Cogut, V.; Bruintjes, J. J.; Eggen, B. J. L.; van der Zee, E. A.; Henning, R. H.

    Hibernators tolerate low metabolism, reduced cerebral blood flow and hypothermia during torpor without noticeable neuronal or synaptic dysfunction upon arousal. Previous studies found extensive changes in brain during torpor, including synaptic rearrangements, documented both morphologically and

  7. Hibernation in black bears: independence of metabolic suppression from body temperature.

    Science.gov (United States)

    Tøien, Øivind; Blake, John; Edgar, Dale M; Grahn, Dennis A; Heller, H Craig; Barnes, Brian M

    2011-02-18

    Black bears hibernate for 5 to 7 months a year and, during this time, do not eat, drink, urinate, or defecate. We measured metabolic rate and body temperature in hibernating black bears and found that they suppress metabolism to 25% of basal rates while regulating body temperature from 30° to 36°C, in multiday cycles. Heart rates were reduced from 55 to as few as 9 beats per minute, with profound sinus arrhythmia. After returning to normal body temperature and emerging from dens, bears maintained a reduced metabolic rate for up to 3 weeks. The pronounced reduction and delayed recovery of metabolic rate in hibernating bears suggest that the majority of metabolic suppression during hibernation is independent of lowered body temperature.

  8. Metabolic Changes in Summer Active and Anuric Hibernating Free-Ranging Brown Bears (Ursus arctos)

    Science.gov (United States)

    Stenvinkel, Peter; Fröbert, Ole; Anderstam, Björn; Palm, Fredrik; Eriksson, Monica; Bragfors-Helin, Ann-Christin; Qureshi, Abdul Rashid; Larsson, Tobias; Friebe, Andrea; Zedrosser, Andreas; Josefsson, Johan; Svensson, My; Sahdo, Berolla; Bankir, Lise; Johnson, Richard J.

    2013-01-01

    The brown bear (Ursus arctos) hibernates for 5 to 6 months each winter and during this time ingests no food or water and remains anuric and inactive. Despite these extreme conditions, bears do not develop azotemia and preserve their muscle and bone strength. To date most renal studies have been limited to small numbers of bears, often in captive environments. Sixteen free-ranging bears were darted and had blood drawn both during hibernation in winter and summer. Samples were collected for measurement of creatinine and urea, markers of inflammation, the calcium-phosphate axis, and nutritional parameters including amino acids. In winter the bear serum creatinine increased 2.5 fold despite a 2-fold decrease in urea, indicating a remarkable ability to recycle urea nitrogen during hibernation. During hibernation serum calcium remained constant despite a decrease in serum phosphate and a rise in FGF23 levels. Despite prolonged inactivity and reduced renal function, inflammation does not ensue and bears seem to have enhanced antioxidant defense mechanisms during hibernation. Nutrition parameters showed high fat stores, preserved amino acids and mild hyperglycemia during hibernation. While total, essential, non-essential and branched chain amino acids concentrations do not change during hibernation anorexia, changes in individual amino acids ornithine, citrulline and arginine indicate an active, although reduced urea cycle and nitrogen recycling to proteins. Serum uric acid and serum fructose levels were elevated in summer and changes between seasons were positively correlated. Further studies to understand how bears can prevent the development of uremia despite minimal renal function during hibernation could provide new therapeutic avenues for the treatment of human kidney disease. PMID:24039826

  9. Generación de código Hibernate desde modelos UML

    OpenAIRE

    Nogueiro Mariscal, Alejandro

    2012-01-01

    Este proyecto consiste en un generador de código para Hibernate desde modelos UML. El código generado es el conjunto de clases del modelo implementadas en Java con una serie de anotaciones JPA 2.0. Estas clases, mediante Hibernate, sirven para añadir persistencia a nuestro código. Los modelos UML tendrán una serie de anotaciones para poder transformarlos correctamente.

  10. Metabolic changes in summer active and anuric hibernating free-ranging brown bears (Ursus arctos.

    Directory of Open Access Journals (Sweden)

    Peter Stenvinkel

    Full Text Available The brown bear (Ursus arctos hibernates for 5 to 6 months each winter and during this time ingests no food or water and remains anuric and inactive. Despite these extreme conditions, bears do not develop azotemia and preserve their muscle and bone strength. To date most renal studies have been limited to small numbers of bears, often in captive environments. Sixteen free-ranging bears were darted and had blood drawn both during hibernation in winter and summer. Samples were collected for measurement of creatinine and urea, markers of inflammation, the calcium-phosphate axis, and nutritional parameters including amino acids. In winter the bear serum creatinine increased 2.5 fold despite a 2-fold decrease in urea, indicating a remarkable ability to recycle urea nitrogen during hibernation. During hibernation serum calcium remained constant despite a decrease in serum phosphate and a rise in FGF23 levels. Despite prolonged inactivity and reduced renal function, inflammation does not ensue and bears seem to have enhanced antioxidant defense mechanisms during hibernation. Nutrition parameters showed high fat stores, preserved amino acids and mild hyperglycemia during hibernation. While total, essential, non-essential and branched chain amino acids concentrations do not change during hibernation anorexia, changes in individual amino acids ornithine, citrulline and arginine indicate an active, although reduced urea cycle and nitrogen recycling to proteins. Serum uric acid and serum fructose levels were elevated in summer and changes between seasons were positively correlated. Further studies to understand how bears can prevent the development of uremia despite minimal renal function during hibernation could provide new therapeutic avenues for the treatment of human kidney disease.

  11. Large intestine bacterial flora of nonhibernating and hibernating leopard frogs (Rana pipiens).

    OpenAIRE

    Gossling, J; Loesche, W J; Nace, G W

    1982-01-01

    The bacteria in the large intestines of 10 northern leopard frogs (Rana pipiens) were enumerated and partially characterized. Four nonhibernating frogs were collected in the summer, four hibernating frogs were collected in the winter, and two frogs just emerged from hibernation were collected in the spring. All frogs had about 10(10) bacteria per g (wet weight) of intestinal contents and about 10(9) bacteria per g (wet weight) of mucosal scraping, although the counts from the winter frogs wer...

  12. Effects of food store quality on hibernation performance in common hamsters.

    Directory of Open Access Journals (Sweden)

    Carina Siutz

    Full Text Available Hibernating animals can adjust torpor expression according to available energy reserves. Besides the quantity, the quality of energy reserves could play an important role for overwintering strategies. Common hamsters are food-storing hibernators and show high individual variation in hibernation performance, which might be related to the quality of food hoards in the hibernacula. In this study, we tested the effects of food stores high in fat content, particularly polyunsaturated fatty acids (PUFAs, on hibernation patterns under laboratory conditions. Control animals received standard rodent pellets only, while in the other group pellets were supplemented with sunflower seeds. We recorded body temperature during winter using subcutaneously implanted data loggers, documented total food consumption during winter, and analysed PUFA proportions in white adipose tissue (WAT before and after the winter period. About half of the individuals in both groups hibernated and torpor expression did not differ between these animals. Among the high-fat group, however, individuals with high sunflower seeds intake strongly reduced the time spent in deep torpor. PUFA proportions in WAT decreased during winter in both groups and this decline was positively related to the time an individual spent in deep torpor. Sunflower seeds intake dampened the PUFA decline resulting in higher PUFA levels in animals of the high-fat group after winter. In conclusion, our results showed that common hamsters adjusted torpor expression and food intake in relation to the total energy of food reserves, underlining the importance of food hoard quality on hibernation performance.

  13. Serotonergic modulation of hippocampal pyramidal cells in euthermic, cold-acclimated, and hibernating hamsters

    Science.gov (United States)

    Horrigan, D. J.; Horwitz, B. A.; Horowitz, J. M.

    1997-01-01

    Serotonergic fibers project to the hippocampus, a brain area previously shown to have distinctive changes in electroencephalograph (EEG) activity during entrance into and arousal from hibernation. The EEG activity is generated by pyramidal cells in both hibernating and nonhibernating species. Using the brain slice preparation, we characterized serotonergic responses of these CA1 pyramidal cells in euthermic, cold-acclimated, and hibernating Syrian hamsters. Stimulation of Shaffer-collateral/commissural fibers evoked fast synaptic excitation of CA1 pyramidal cells, a response monitored by recording population spikes (the synchronous generation of action potentials). Neuromodulation by serotonin (5-HT) decreased population spike amplitude by 54% in cold-acclimated animals, 80% in hibernating hamsters, and 63% in euthermic animals. The depression was significantly greater in slices from hibernators than from cold-acclimated animals. In slices from euthermic animals, changes in extracellular K+ concentration between 2.5 and 5.0 mM did not significantly alter serotonergic responses. The 5-HT1A agonist 8-hydroxy-2(di-n-propylamino)tetralin mimicked serotonergic inhibition in euthermic hamsters. Results show that 5-HT is a robust neuromodulator not only in euthermic animals but also in cold-acclimated and hibernating hamsters.

  14. Long-term video surveillance and automated analyses reveal arousal patterns in groups of hibernating bats

    Science.gov (United States)

    Hayman, David T.S.; Cryan, Paul; Fricker, Paul D.; Dannemiller, Nicholas G.

    2017-01-01

    Understanding natural behaviours is essential to determining how animals deal with new threats (e.g. emerging diseases). However, natural behaviours of animals with cryptic lifestyles, like hibernating bats, are often poorly characterized. White-nose syndrome (WNS) is an unprecedented disease threatening multiple species of hibernating bats, and pathogen-induced changes to host behaviour may contribute to mortality. To better understand the behaviours of hibernating bats and how they might relate to WNS, we developed new ways of studying hibernation across entire seasons.We used thermal-imaging video surveillance cameras to observe little brown bats (Myotis lucifugus) and Indiana bats (M. sodalis) in two caves over multiple winters. We developed new, sharable software to test for autocorrelation and periodicity of arousal signals in recorded video.We processed 740 days (17,760 hr) of video at a rate of >1,000 hr of video imagery in less than 1 hr using a desktop computer with sufficient resolution to detect increases in arousals during midwinter in both species and clear signals of daily arousal periodicity in infected M. sodalis.Our unexpected finding of periodic synchronous group arousals in hibernating bats demonstrate the potential for video methods and suggest some bats may have innate behavioural strategies for coping with WNS. Surveillance video and accessible analysis software make it now practical to investigate long-term behaviours of hibernating bats and other hard-to-study animals.

  15. Investigating the mechanism for maintaining eucalcemia despite immobility and anuria in the hibernating American black bear (Ursus americanus).

    Science.gov (United States)

    Seger, Rita L; Cross, Randal A; Rosen, Clifford J; Causey, Robert C; Gundberg, Caren M; Carpenter, Thomas O; Chen, Tai C; Halteman, William A; Holick, Michael F; Jakubas, Walter J; Keisler, Duane H; Seger, Richard M; Servello, Frederick A

    2011-12-01

    Ursine hibernation uniquely combines prolonged skeletal unloading, anuria, pregnancy, lactation, protein recycling, and lipolysis. This study presents a radiographic and biochemical picture of bone metabolism in free-ranging, female American black bears (Ursus americanus) that were active (spring bears and autumn bears) or hibernating (hibernating bears). Hibernating bears included lactating and non-lactating individuals. We measured serum calcium, albumin, inorganic phosphate, creatinine, bone specific alkaline phosphatase (BSALP), CTX, parathyroid hormone, insulin-like growth factor-I (IGF-l), leptin, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D] and sclerostin from 35 to 50 tranquilized hibernating bears and 14 to 35 tranquilized spring bears. We compared metacarpal cortical indices (MCI), measured by digital X-ray radiogrammetry, from 60 hunter-killed autumn bears and 79 tranquilized, hibernating bears. MCI was greater in autumn than winter in younger bears, but showed no seasonal difference in older bears. During hibernation eucalcemia was maintained, BSALP was suppressed, and CTX was in the range expected for anuria. During hibernation 1,25(OH)(2)D was produced despite anuria. 1,25(OH)(2)D and IGF-I were less in hibernating than spring bears. In a quarter of hibernating bears, sclerostin was elevated. Leptin was greater in hibernating than spring bears. In hibernating bears, leptin correlated positively with BSALP in non-lactating bears and with CTX in lactating bears. Taken together the biochemical and radiographic findings indicate that during hibernation, bone turnover was persistent, balanced, and suppressed; bone resorption was lower than expected for an unloaded skeleton; and there was no unloading-induced bone loss. The skeleton appears to perceive that it was loaded when it was actually unloaded during hibernation. However, at the level of sclerostin, the skeleton recognized that it was unloaded. During hibernation leptin

  16. Hibernation, a State of Natural Tolerance to Profound Reduction in Organ Blood Flow and Oxygen Delivery Capacity

    National Research Council Canada - National Science Library

    McCarron, Richard

    2001-01-01

    .... Hibernating animals exhibit multiple biological alterations which contribute to their dramatic ability to tolerate the ischaemic conditions associated with reduced rates of respiration and blood flow...

  17. Diet-independent remodeling of cellular membranes precedes seasonally changing body temperature in a hibernator.

    Directory of Open Access Journals (Sweden)

    Walter Arnold

    Full Text Available Polyunsaturated fatty acids (PUFA have a multitude of health effects. Their incorporation into membrane phospholipids (PL is generally believed to depend directly on dietary influx. PL influence transmembrane protein activity and thus can compensate temperature effects; e.g. PL n-6 PUFA are thought to stabilize heart function at low body temperature (T(b, whereas long chain (>C18 n-3 PUFA may boost oxidative capacity. We found substantial remodeling of membranes in free-living alpine marmots which was largely independent of direct dietary supply. Organ PL n-6 PUFA and n-6 to n-3 ratios were highest at onset and end of hibernation after rapid increases during a brief transitional period prior to hibernation. In contrast, longer chain PL n-3 PUFA content was low at end of summer but maximal at end of hibernation. After termination of hibernation in spring, these changes in PL composition were rapidly reversed. Our results demonstrate selective trafficking of PUFA within the body, probably governed by a circannual endogenous rhythm, as hibernating marmots were in winter burrows isolated for seven months from food and external cues signaling the approaching spring. High concentrations of PL n-6 PUFA throughout hibernation are in line with their hypothesized function of boosting SERCA 2a activity at low T(b. Furthermore, we found increasing rate of rewarming from torpor during winter indicating increasing oxidative capacity that could be explained by the accumulation of long-chain PL n-3 PUFA. It may serve to minimize the time necessary for rewarming despite the increasing temperature range to be covered, because rewarming is a period of highest metabolic rate and hence production of reactive oxygen species. Considering the importance of PUFA for health our results may have important biomedical implications, as seasonal changes of T(b and associated remodeling of membranes are not restricted to hibernators but presumably common among endothermic

  18. Hibernal habitat selection by Wood Frogs (Lithobates sylvaticus) in a northern New England montane landscape

    Science.gov (United States)

    Groff, Luke A.; Calhoun, Aram J.K.; Loftin, Cynthia S.

    2016-01-01

    Poikilothermic species, such as amphibians, endure harsh winter conditions via freeze-tolerance or freeze-avoidance strategies. Freeze-tolerance requires a suite of complex, physiological mechanisms (e.g., cryoprotectant synthesis); however, behavioral strategies (e.g., hibernal habitat selection) may be used to regulate hibernaculum temperatures and promote overwintering survival. We investigated the hibernal ecology of the freeze-tolerant Wood Frog (Lithobates sylvaticus) in north-central Maine. Our objectives were to characterize the species hibernaculum microclimate (temperature, relative humidity), evaluate hibernal habitat selection, and describe the spatial arrangement of breeding, post-breeding, and hibernal habitats. We monitored 15 frogs during two winters (2011/12: N = 10; 2012/13: N = 5), measured hibernal habitat features at micro (2 m) and macro (10 m) spatial scales, and recorded microclimate hourly in three strata (hibernaculum, leaf litter, ambient air). We compared these data to that of 57 random locations with logistic regression models, Akaike Information Criterion, and Kolmogorov–Smirnov tests. Hibernaculum microclimate was significantly different and less variable than leaf litter, ambient air, and random location microclimate. Model averaging indicated that canopy cover (−), leaf litter depth (+), and number of logs and stumps (+; microhabitat only) were important predictors of Wood Frog hibernal habitat. These habitat features likely act to insulate hibernating frogs from extreme and variable air temperatures. For example, decreased canopy cover facilitates increased snowpack depth and earlier snowpack accumulation and melt. Altered winter temperature and precipitation patterns attributable to climate change may reduce snowpack insulation, facilitate greater temperature variation in the underlying hibernacula, and potentially compromise Wood Frog winter survival.

  19. Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus

    Directory of Open Access Journals (Sweden)

    Yan Jun

    2011-03-01

    Full Text Available Abstract Background Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. Results We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3, which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Conclusions Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.

  20. Amygdalar glutamatergic neuronal systems play a key role on the hibernating state of hamsters

    Directory of Open Access Journals (Sweden)

    Facciolo Rosa

    2011-01-01

    Full Text Available Abstract Background Excitatory transmitting mechanisms are proving to play a critical role on neuronal homeostasis conditions of facultative hibernators such as the Syrian golden hamster. Indeed works have shown that the glutamatergic system of the main olfactory brain station (amygdala is capable of controlling thermoregulatory responses, which are considered vital for the different hibernating states. In the present study the role of amygdalar glutamatergic circuits on non-hibernating (NHIB and hibernating (HIB hamsters were assessed on drinking stimuli and subsequently compared to expression variations of some glutamatergic subtype mRNA levels in limbic areas. For this study the two major glutamatergic antagonists and namely that of N-methyl-D-aspartate receptor (NMDAR, 3-(+-2-carboxypiperazin-4-yl-propyl-1-phosphonate (CPP plus that of the acid α-amine-3-hydroxy-5-metil-4-isoxazol-propionic receptor (AMPAR site, cyano-7-nitro-quinoxaline-2,3-dione (CNQX were infused into the basolateral amygdala nucleus. Attempts were made to establish the type of effects evoked by amygdalar glutamatergic cross-talking processes during drinking stimuli, a response that may corroborate their major role at least during some stages of this physiological activity in hibernators. Results From the behavioral results it appears that the two glutamatergic compounds exerted distinct effects. In the first case local infusion of basolateral complexes (BLA with NMDAR antagonist caused very great (p Conclusion We conclude that predominant drinking events evoked by glutamatergic mechanisms, in the presence of prevalently down regulated levels of NR1/2A of some telencephalic and hypothalamic areas appear to constitute an important neuronal switch at least during arousal stage of hibernation. The establishment of the type of glutamatergic subtypes that are linked to successful hibernating states, via drinking stimuli, may have useful bearings toward sleeping disorders.

  1. Weights and hematology of wild black bears during hibernation

    Science.gov (United States)

    DelGiudice, Glenn D.; Rogers, Lynn L.; Allen, Arthur W.; Seal, U.S.

    1991-01-01

    We compared weights and hematological profiles of adult (greater than 3-yr-old) female black bears (Ursus americanus) during hibernation (after 8 January). We handled 28 bears one to four times (total of 47) over 4 yr of varying mast and berry production. Mean weight of lactating bears was greater (P less than 0.0001) than that of non-lactating females. White blood cells (P less than 0.05) and mean corpuscular volume (P = 0.005) also differed between lactating and non-lactating bears. Hemoglobin (P = 0.006) and mean corpuscular hemoglobin concentration (P = 0.02) varied among years; values were lowest during 1975, following decreased precipitation and the occurrence of a second year of mast and berry crop shortages in a three-year period. Significant (P less than 0.05) interaction between reproductive status (lactating versus non-lactating) and study year for hemoglobin, red blood cells, and packed cell volume, and increased mean corpuscular volume, suggested a greater nutritional challenge for lactating females compared to non-lactating females during the 1975 denning season. Our data suggest that hematological characteristics of denning bears may be more sensitive than weights as indicators of annual changes in nutritional status; however, other influential factors, in addition to mast and berry crop production, remain to be examined.

  2. The cell nuclei of skeletal muscle cells are transcriptionally active in hibernating edible dormice

    Directory of Open Access Journals (Sweden)

    Muller Sylviane

    2009-03-01

    Full Text Available Abstract Background Skeletal muscle is able to react in a rapid, dynamic way to metabolic and mechanical stimuli. In particular, exposure to either prolonged starvation or disuse results in muscle atrophy. At variance, in hibernating animals muscle atrophy may be scarce or absent after bouts of hibernation i.e., periods of prolonged (months inactivity and food deprivation, and muscle function is fully preserved at arousal. In this study, myocytes from the quadriceps muscle of euthermic and hibernating edible dormice were investigated by a combination of morphological, morphometrical and immunocytochemical analyses at the light and electron microscopy level. The focus was on cell nuclei and mitochondria, which are highly sensitive markers of changing metabolic rate. Results Findings presented herein demonstrate that: 1 the general histology of the muscle, inclusive of muscle fibre shape and size, and the ratio of fast and slow fibre types are not affected by hibernation; 2 the fine structure of cytoplasmic and nuclear constituents is similar in euthermia and hibernation but for lipid droplets, which accumulate during lethargy; 3 during hibernation, mitochondria are larger in size with longer cristae, and 4 myonuclei maintain the same amount and distribution of transcripts and transcription factors as in euthermia. Conclusion In this study we demonstrate that skeletal muscle cells of the hibernating edible dormouse maintain their structural and functional integrity in full, even after months in the nest. A twofold explanation for that is envisaged: 1 the maintenance, during hibernation, of low-rate nuclear and mitochondrial activity counterbalancing myofibre wasting, 2 the intensive muscle stimulation (shivering during periodic arousals in the nest, which would mimic physical exercise. These two factors would prevent muscle atrophy usually occurring in mammals after prolonged starvation and/or inactivity as a consequence of prevailing catabolism

  3. Quality and biochemical properties of artificially hibernated crucian carp for waterless preservation.

    Science.gov (United States)

    Mi, Hongbo; Qian, Chunlu; Mao, Linchun

    2012-12-01

    The aim of this study was to explore the artificial hibernation of crucian carp for waterless preservation and to characterize the quality and biochemical properties during and after the hibernation. Anesthetized crucian carp using eugenol were stored at 8 °C with 90 % oxygen and 95-100 % relative humidity for 38 h and then transferred to fresh water to recover. Liquid loss and cooking loss had no significant changes (p > 0.05). The total volatile basic nitrogen content and 2-thiobarbituric acid value in hibernated fish were significantly higher (p 0.05). Both ACP and AKP activities decreased upon the fish recovered, but only the ACP activity returned to normal. However, there were increased serum glucose concentration, GOT and GPT activities in recovered fish. On the basis of these findings, it can be concluded that the artificially hibernated life of crucian carp was 38 h by the combination of anaesthetizing and low temperature. The muscle quality would not be influenced, and most of the stress responses would disappear after hibernated fish recovered.

  4. Mammal survival at the Cretaceous-Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs.

    Science.gov (United States)

    Lovegrove, Barry G; Lobban, Kerileigh D; Levesque, Danielle L

    2014-12-07

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tropical hibernation that we report might explain how the ancestral placental mammal survived the global devastation that drove the dinosaurs and many other vertebrates to extinction at the Cretaceous-Palaeogene boundary following a meteorite impact. The genetics and biochemistry of IBAs are of immense interest to biomedical researchers and space exploration scientists, in the latter case, those envisioning a hibernating state in astronauts for deep space travel. Unravelling the physiological thresholds and temperature dependence of IBAs will provide new impetus to these research quests. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  5. Mammal survival at the Cretaceous–Palaeogene boundary: metabolic homeostasis in prolonged tropical hibernation in tenrecs

    Science.gov (United States)

    Lovegrove, Barry G.; Lobban, Kerileigh D.; Levesque, Danielle L.

    2014-01-01

    Free-ranging common tenrecs, Tenrec ecaudatus, from sub-tropical Madagascar, displayed long-term (nine months) hibernation which lacked any evidence of periodic interbout arousals (IBAs). IBAs are the dominant feature of the mammalian hibernation phenotype and are thought to periodically restore long-term ischaemia damage and/or metabolic imbalances (depletions and accumulations). However, the lack of IBAs in tenrecs suggests no such pathology at hibernation Tbs > 22°C. The long period of tropical hibernation that we report might explain how the ancestral placental mammal survived the global devastation that drove the dinosaurs and many other vertebrates to extinction at the Cretaceous–Palaeogene boundary following a meteorite impact. The genetics and biochemistry of IBAs are of immense interest to biomedical researchers and space exploration scientists, in the latter case, those envisioning a hibernating state in astronauts for deep space travel. Unravelling the physiological thresholds and temperature dependence of IBAs will provide new impetus to these research quests. PMID:25339721

  6. Stochastic population dynamics of a montane ground-dwelling squirrel.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Hostetler

    Full Text Available Understanding the causes and consequences of population fluctuations is a central goal of ecology. We used demographic data from a long-term (1990-2008 study and matrix population models to investigate factors and processes influencing the dynamics and persistence of a golden-mantled ground squirrel (Callospermophilus lateralis population, inhabiting a dynamic subalpine habitat in Colorado, USA. The overall deterministic population growth rate λ was 0.94±SE 0.05 but it varied widely over time, ranging from 0.45±0.09 in 2006 to 1.50±0.12 in 2003, and was below replacement (λ<1 for 9 out of 18 years. The stochastic population growth rate λ(s was 0.92, suggesting a declining population; however, the 95% CI on λ(s included 1.0 (0.52-1.60. Stochastic elasticity analysis showed that survival of adult females, followed by survival of juvenile females and litter size, were potentially the most influential vital rates; analysis of life table response experiments revealed that the same three life history variables made the largest contributions to year-to year changes in λ. Population viability analysis revealed that, when the influences of density dependence and immigration were not considered, the population had a high (close to 1.0 in 50 years probability of extinction. However, probability of extinction declined to as low as zero when density dependence and immigration were considered. Destabilizing effects of stochastic forces were counteracted by regulating effects of density dependence and rescue effects of immigration, which allowed our study population to bounce back from low densities and prevented extinction. These results suggest that dynamics and persistence of our study population are determined synergistically by density-dependence, stochastic forces, and immigration.

  7. Black bears with longer disuse (hibernation) periods have lower femoral osteon population density and greater mineralization and intracortical porosity.

    Science.gov (United States)

    Wojda, Samantha J; Weyland, David R; Gray, Sarah K; McGee-Lawrence, Meghan E; Drummer, Thomas D; Donahue, Seth W

    2013-08-01

    Intracortical bone remodeling is persistent throughout life, leading to age related increases in osteon population density (OPD). Intracortical porosity also increases with age in many mammals including humans, contributing to bone fragility and fracture risk. Unbalanced bone resorption and formation during disuse (e.g., physical inactivity) also increases intracortical porosity. In contrast, hibernating bears are a naturally occurring model for the prevention of both age-related and disuse osteoporoses. Intracortical bone remodeling is decreased during hibernation, but resorption and formation remain balanced. Black bears spend 0.25-7 months in hibernation annually depending on climate and food availability. We found longer hibernating bears demonstrate lower OPD and higher cortical bone mineralization than bears with shorter hibernation durations, but we surprisingly found longer hibernating bears had higher intracortical porosity. However, bears from three different latitudes showed age-related decreases in intracortical porosity, indicating that regardless of hibernation duration, black bears do not show the disuse- or age-related increases in intracortical porosity which is typical of other animals. This ability to prevent increases in intracortical porosity likely contributes to their ability to maintain bone strength during prolonged periods of physical inactivity and throughout life. Improving our understanding of the unique bone metabolism in hibernating bears will potentially increase our ability to develop treatments for age- and disuse-related osteoporoses in humans. Copyright © 2013 Wiley Periodicals, Inc.

  8. Preservation of bone mass and structure in hibernating black bears (Ursus americanus) through elevated expression of anabolic genes.

    Science.gov (United States)

    Fedorov, Vadim B; Goropashnaya, Anna V; Tøien, Øivind; Stewart, Nathan C; Chang, Celia; Wang, Haifang; Yan, Jun; Showe, Louise C; Showe, Michael K; Donahue, Seth W; Barnes, Brian M

    2012-06-01

    Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non-hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non-hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P 1.4) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment Analysis showed an elevated proportion in hibernating bears of overexpressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development, and bone biosynthesis. Apoptosis genes demonstrated a tendency for downregulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, and c-Fos) were significantly underexpressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis-related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation.

  9. Infection and transmission of Nosema bombi in Bombus terrestris colonies and its effect on hibernation, mating and colony founding

    NARCIS (Netherlands)

    Steen, van der J.J.M.

    2008-01-01

    The impact of the microsporidium Nosema bombi on Bombus terrestris was studied by recording mating, hibernation success, protein titre in haemolymph, weight change during hibernation, and colony founding of queens that were inoculated with N. bombi in the larval phase. Infection with N. bombi was

  10. Skeletal muscles of hibernating brown bears are unusually resistant to effects of denervation.

    Science.gov (United States)

    Lin, David C; Hershey, John D; Mattoon, John S; Robbins, Charles T

    2012-06-15

    Hibernating bears retain most of their skeletal muscle strength despite drastically reduced weight-bearing activity. Regular neural activation of muscles is a potential mechanism by which muscle atrophy could be limited. However, both mechanical loading and neural activity are usually necessary to maintain muscle size. An alternative mechanism is that the signaling pathways related to the regulation of muscle size could be altered so that neither mechanical nor neural inputs are needed for retaining strength. More specifically, we hypothesized that muscles in hibernating bears are resistant to a severe reduction in neural activation. To test this hypothesis, we unilaterally transected the common peroneal nerve, which innervates ankle flexor muscles, in hibernating and summer-active brown bears (Ursus arctos). In hibernating bears, the long digital extensor (LDE) and cranial tibial (CT) musculotendon masses on the denervated side decreased after 11 weeks post-surgery by 18 ± 11 and 25 ± 10%, respectively, compared with those in the intact side. In contrast, decreases in musculotendon masses of summer-active bears after denervation were 61 ± 4 and 58 ± 5% in the LDE and CT, respectively, and significantly different from those of hibernating bears. The decrease due to denervation in summer-active bears was comparable to that occurring in other mammals. Whole-muscle cross-sectional areas (CSAs) measured from ultrasound images and myofiber CSAs measured from biopsies decreased similarly to musculotendon mass. Thus, hibernating bears alter skeletal muscle catabolic pathways regulated by neural activity, and exploration of these pathways may offer potential solutions for disuse atrophy of muscles.

  11. Molecular mechanisms regulating oxygen transport and consumption in high altitude and hibernating mammals

    DEFF Research Database (Denmark)

    Revsbech, Inge Grønvall

    2016-01-01

    The aim of this thesis is to broaden the knowledge of molecular mechanisms of adjustment in oxygen (O2) uptake, conduction, delivery and consumption in mammals adapted to extreme conditions. For this end, I have worked with animals living at high altitude as an example of environmental hypoxia...... of the repeatedly found adaptive traits in animals living at high altitude and in hibernating mammals during hibernation compared with the active state. Factors that affect O2 affinity of Hb include temperature, H+/CO2 via the Bohr effect as well as Cl- and organic phosphates, in mammals mainly 2...

  12. Hormones and hibernation: possible links between hormone systems, winter energy balance and white-nose syndrome in bats.

    Science.gov (United States)

    Willis, Craig K R; Wilcox, Alana

    2014-06-01

    This article is part of a Special Issue "Energy Balance". Hibernation allows mammals to survive in cold climates and during times of reduced food availability. Drastic physiological changes are required to maintain the energy savings that characterize hibernation. These changes presumably enable adjustments in endocrine activity that control metabolism and body temperature, and ultimately influence expression of torpor and periodic arousals. Despite challenges that exist when examining hormonal pathways in small-bodied hibernators, bats represent a potential model taxon for comparative neuroendocrinological studies of hibernation due to their diversity of species and the reliance of many species on heterothermy. Understanding physiological mechanisms underlying hibernation in bats is also important from a conservation physiology perspective due to white-nose syndrome, an emerging infectious disease causing catastrophic mortality among hibernating bats in eastern North America. Here we review the potential influence of three key hormonal mechanisms--leptin, melatonin and glucocorticoids--on hibernation in mammals with an emphasis on bats. We propose testable hypotheses about potential effects of WNS on these systems and their evolution. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. A review of factors affecting cave climates for hibernating bats in temperate North America

    Science.gov (United States)

    Roger W. Perry

    2013-01-01

    The fungal pathogen Geomyces destructans, which causes white-nose syndrome in bats, thrives in the cold and moist conditions found in caves where bats hibernate. To aid managers and researchers address this disease, an updated and accessible review of cave hibernacula and cave microclimates is presented. To maximize energy savings and reduce...

  14. Sperm influences female hibernation success, survival and fitness in the bumble-bee Bombus terrestris

    DEFF Research Database (Denmark)

    Baer, Boris; Schmid-Hempel, Paul

    2005-01-01

    . Using the bumble-bee Bombus terrestris, we artificially inseminated queens (females) with sperm from one or several males and show that sire groups (groups of brother males) vary in their effects on queen hibernation survival, longevity and fitness. In addition, multiply inseminated queens always had...

  15. Effects of white-nose syndrome on regional population patterns of 3 hibernating bat species

    Science.gov (United States)

    Thomas E. Ingersoll; Brent J. Sewall; Sybill K. Amelon

    2016-01-01

    Hibernating bats have undergone severe recent declines across the eastern United States, but the cause of these regional-scale declines has not been systematically evaluated. We assessed the influence of white-nose syndrome (an emerging bat disease caused by the fungus Pseudogymnoascus destructans, formerly Geomyces destructans...

  16. Adaptive plasticity of skeletal muscle energetics in hibernating frogs: mitochondrial proton leak during metabolic depression.

    Science.gov (United States)

    Boutilier, Robert G; St-Pierre, Julie

    2002-08-01

    The common frog (Rana temporaria) spends the coldest months of each year overwintering in ice-covered ponds where temperatures can vary from 0.5 to 4.0 degrees C. Over the course of a winter season, the animals enter progressively into a state of metabolic depression that relies almost exclusively on aerobic production of ATP. However, if aerobic metabolism is threatened, for example by increasingly hypoxic conditions, decreases in the animal's metabolic rate can reach upwards of 75% compared with the 50% decrease seen during normoxia. Under these conditions, the major proportion of the overall reduction in whole-animal metabolic rate can be accounted for by metabolic suppression of the skeletal muscle (which makes up approximately 40% of body mass). Little is known about the properties of mitochondria during prolonged periods of metabolic depression, so we have examined several aspects of mitochondrial metabolism in the skeletal muscle of frogs over periods of hibernation of up to 4 months. Mitochondria isolated from the skeletal muscle of frogs hibernating in hypoxic water show a considerable reorganisation of function compared with those isolated from normoxic submerged animals at the same temperature (3 degrees C). Both the active (state 3) and resting (state 4) respiration rates of mitochondria decrease during hypoxic, but not normoxic, hibernation. In addition, the affinity of mitochondria for oxygen increases during periods of acute hypoxic stress during normoxic hibernation as well as during long-term hibernation in hypoxic water. The decrease in mitochondrial state 4 respiration rates during hypoxic hibernation evidently occurs through a reduction in electron-transport chain activity, not through a lowered proton conductance of the mitochondrial inner membrane. The reduced aerobic capacity of frog skeletal muscle during hypoxic hibernation is accompanied by lowered activities of key enzymes of mitochondrial metabolism caused by changes in the intrinsic

  17. White-nose syndrome initiates a cascade of physiologic disturbances in the hibernating bat host.

    Science.gov (United States)

    Verant, Michelle L; Meteyer, Carol U; Speakman, John R; Cryan, Paul M; Lorch, Jeffrey M; Blehert, David S

    2014-12-09

    The physiological effects of white-nose syndrome (WNS) in hibernating bats and ultimate causes of mortality from infection with Pseudogymnoascus (formerly Geomyces) destructans are not fully understood. Increased frequency of arousal from torpor described among hibernating bats with late-stage WNS is thought to accelerate depletion of fat reserves, but the physiological mechanisms that lead to these alterations in hibernation behavior have not been elucidated. We used the doubly labeled water (DLW) method and clinical chemistry to evaluate energy use, body composition changes, and blood chemistry perturbations in hibernating little brown bats (Myotis lucifugus) experimentally infected with P. destructans to better understand the physiological processes that underlie mortality from WNS. These data indicated that fat energy utilization, as demonstrated by changes in body composition, was two-fold higher for bats with WNS compared to negative controls. These differences were apparent in early stages of infection when torpor-arousal patterns were equivalent between infected and non-infected animals, suggesting that P. destructans has complex physiological impacts on its host prior to onset of clinical signs indicative of late-stage infections. Additionally, bats with mild to moderate skin lesions associated with early-stage WNS demonstrated a chronic respiratory acidosis characterized by significantly elevated dissolved carbon dioxide, acidemia, and elevated bicarbonate. Potassium concentrations were also significantly higher among infected bats, but sodium, chloride, and other hydration parameters were equivalent to controls. Integrating these novel findings on the physiological changes that occur in early-stage WNS with those previously documented in late-stage infections, we propose a multi-stage disease progression model that mechanistically describes the pathologic and physiologic effects underlying mortality of WNS in hibernating bats. This model identifies

  18. Low cardiac output as physiological phenomenon in hibernating, free-ranging Scandinavian brown bears (Ursus arctos) - an observational study.

    Science.gov (United States)

    Jørgensen, Peter Godsk; Arnemo, Jon; Swenson, Jon E; Jensen, Jan S; Galatius, Søren; Frøbert, Ole

    2014-09-16

    Despite 5-7 months of physical inactivity during hibernation, brown bears (Ursus arctos) are able to cope with physiological conditions that would be detrimental to humans. During hibernation, the tissue metabolic demands fall to 25% of the active state. Our objective was to assess cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears. We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter hibernation in February 2013 and with medetomidine-zolazepam-tiletamine during active state in June 2013. We measured cardiac output noninvasively using estimates of hemodynamics obtained by pulsed wave Doppler echocardiography and 2D imaging. Comparisons were made using paired T-tests. During hibernation, all hemodynamic indices were significantly decreased (hibernating vs. active state): mean heart rate was 26.0 (standard deviation (SD): 5.6) beats per min vs. 75.0 (SD: 17.1) per min (P=0.002), mean stroke volume 32.3 (SD: 5.2) ml vs. 47.1 (SD: 7.9) ml (P=0.008), mean cardiac output 0.86 (SD: 0.31) l/min vs. 3.54 (SD: 1.04) l/min (P=0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m2 (Pbears during hibernation, despite the absence of atrial arrhythmias and valvular disease. Free-ranging brown bears demonstrate hemodynamics comparable to humans during active state, whereas during hibernation, we documented extremely low-flow hemodynamics. Understanding these physiological changes in bears may help to gain insight into the mechanisms of cardiogenic shock and heart failure in humans.

  19. Specific alterations in complement protein activity of little brown myotis (Myotis lucifugus hibernating in white-nose syndrome affected sites.

    Directory of Open Access Journals (Sweden)

    Marianne S Moore

    Full Text Available White-nose syndrome (WNS is the most devastating condition ever reported for hibernating bats, causing widespread mortality in the northeastern United States. The syndrome is characterized by cutaneous lesions caused by a recently identified psychrophilic and keratinophylic fungus (Geomyces destructans, depleted fat reserves, atypical behavior, and damage to wings; however, the proximate cause of mortality is still uncertain. To assess relative levels of immunocompetence in bats hibernating in WNS-affected sites compared with levels in unaffected bats, we describe blood plasma complement protein activity in hibernating little brown myotis (Myotis lucifugus based on microbicidal competence assays using Escherichia coli, Staphylococcus aureus and Candida albicans. Blood plasma from bats collected during mid-hibernation at WNS-affected sites had higher bactericidal ability against E. coli and S. aureus, but lower fungicidal ability against C. albicans when compared with blood plasma from bats collected at unaffected sites. Within affected sites during mid-hibernation, we observed no difference in microbicidal ability between bats displaying obvious fungal infections compared to those without. Bactericidal ability against E. coli decreased significantly as hibernation progressed in bats collected from an affected site. Bactericidal ability against E. coli and fungicidal ability against C. albicans were positively correlated with body mass index (BMI during late hibernation. We also compared complement activity against the three microbes within individuals and found that the ability of blood plasma from hibernating M. lucifugus to lyse microbial cells differed as follows: E. coli>S. aureus>C. albicans. Overall, bats affected by WNS experience both relatively elevated and reduced innate immune responses depending on the microbe tested, although the cause of observed immunological changes remains unknown. Additionally, considerable trade-offs may exist

  20. Skin Lesions in European Hibernating Bats Associated with Geomyces destructans, the Etiologic Agent of White-Nose Syndrome

    OpenAIRE

    Wibbelt, Gudrun; Puechmaille, S?bastien J.; Ohlendorf, Bernd; M?hldorfer, Kristin; Bosch, Thijs; G?rf?l, Tam?s; Passior, Karsten; Kurth, Andreas; Lacremans, Daniel; Forget, Fr?d?ric

    2013-01-01

    White-nose syndrome (WNS) has claimed the lives of millions of hibernating insectivorous bats in North America. Its etiologic agent, the psychrophilic fungus Geomyces destructans, causes skin lesions that are the hallmark of the disease. The fungal infection is characterized by a white powdery growth on muzzle, ears and wing membranes. While WNS may threaten some species of North American bats with regional extinction, infection in hibernating bats in Europe seems not to be associated with si...

  1. Specific alterations in complement protein activity of little brown myotis (Myotis lucifugus) hibernating in white-nose syndrome affected sites.

    Science.gov (United States)

    Moore, Marianne S; Reichard, Jonathan D; Murtha, Timothy D; Zahedi, Bita; Fallier, Renee M; Kunz, Thomas H

    2011-01-01

    White-nose syndrome (WNS) is the most devastating condition ever reported for hibernating bats, causing widespread mortality in the northeastern United States. The syndrome is characterized by cutaneous lesions caused by a recently identified psychrophilic and keratinophylic fungus (Geomyces destructans), depleted fat reserves, atypical behavior, and damage to wings; however, the proximate cause of mortality is still uncertain. To assess relative levels of immunocompetence in bats hibernating in WNS-affected sites compared with levels in unaffected bats, we describe blood plasma complement protein activity in hibernating little brown myotis (Myotis lucifugus) based on microbicidal competence assays using Escherichia coli, Staphylococcus aureus and Candida albicans. Blood plasma from bats collected during mid-hibernation at WNS-affected sites had higher bactericidal ability against E. coli and S. aureus, but lower fungicidal ability against C. albicans when compared with blood plasma from bats collected at unaffected sites. Within affected sites during mid-hibernation, we observed no difference in microbicidal ability between bats displaying obvious fungal infections compared to those without. Bactericidal ability against E. coli decreased significantly as hibernation progressed in bats collected from an affected site. Bactericidal ability against E. coli and fungicidal ability against C. albicans were positively correlated with body mass index (BMI) during late hibernation. We also compared complement activity against the three microbes within individuals and found that the ability of blood plasma from hibernating M. lucifugus to lyse microbial cells differed as follows: E. coli>S. aureus>C. albicans. Overall, bats affected by WNS experience both relatively elevated and reduced innate immune responses depending on the microbe tested, although the cause of observed immunological changes remains unknown. Additionally, considerable trade-offs may exist between energy

  2. Identification of ischemic and hibernating myocardium: feasibility of post-exercise F-18 deoxyglucose positron emission tomography

    International Nuclear Information System (INIS)

    Marwick, T.H.; MacIntyre, W.J.; Salcedo, E.E.; Go, R.T.; Saha, G.; Beachler, A.

    1991-01-01

    The identification of ischemic and hibernating myocardium facilitates the selection of patients most likely to benefit from revascularization. This study examined the feasibility of metabolic imaging, using post-exercise F-18 deoxyglucose positron emission tomography (FDG-PET) for the diagnosis of both ischemia and hibernation in 27 patients with known coronary anatomy. Normal post-exercise FDG uptake was defined in each patient by reference to normal resting perfusion and normal coronary supply. Abnormal elevation of FDG (ischemia or hibernation) was compared in 13 myocardial segments in each patient, with the results of dipyridamole stress perfusion imaging performed by rubidium-82 positron emission tomography (Rb-PET). Myocardial ischemia was diagnosed by either FDG-PET or Rb-PET in 34 segments subtended by significant local coronary stenoses. Increased FDG uptake was present in 32/34 (94%) and a reversible perfusion defect was identified by Rb-PET in 22/34 (65%, p less than .01). In 3 patients, ischemia was identified by metabolic imaging alone. In 16 patients with previous myocardial infarction, perfusion defects were present at rest in 89 regions, 30 of which (34%) demonstrated increased FDG uptake, consistent with the presence of hibernation. Increased post-exercise FDG uptake appears to be a sensitive indicator of ischemia and myocardial hibernation. Increased post-exercise FDG uptake, appears to be a sensitive indicator of ischemia and myocardial hibernation. This test may be useful in selecting post-infarction patients for revascularization

  3. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis.

  4. State-dependent variation in the inhibitory effect of (D-Ala sup 2 , D-Leu sup 5 )-enkephalin on hippocampal serotonin release in ground squirrels

    Energy Technology Data Exchange (ETDEWEB)

    Kramarova, L.I.; Lee, T.F.; Cui, Y.; Wang, L.C.H. (Univ. of Alberta, Edmonton (Canada))

    1990-01-01

    Accumulated evidence has suggested that increased endogenous opioid activities may facilitate the onset of hibernation either directly or possibly through modulation of other neurotransmitter systems. The seasonal change of (D-Ala{sup 2}, D-Leu{sup 5})-enkephalin (DADLE), a {delta} receptor agonist, in modulating K{sup +}-induced ({sup 3}H)-5-hydroxytryptamine (5-HT) release from the hippocampal and hypothalamic slices of euthermic and hibernating Richardsons' ground squirrels was therefore investigated. DADLE had no effect on 5-HT release in the hypothalamic slices but elicited a dose-related inhibition on ({sup 3}H)-5-HT release from the hippocampal slices of the euthermic ground squirrel. The inhibitory effect of DADLE was completely reversed by naloxone, but not by tetrodotoxin. In contrast, DADLE failed to alter the K{sup +}-induced 5-HT release from the hippocampal slices of the hibernating ground squirrel. This state-dependent reduction in responsiveness to an opioid is consistent with the hypothesis that enhanced endogenous opioid activity in the hibernating phase could lead to down regulation of the opioid receptors and minimize its inhibition on hippocampal serotonergic activity. A high 5-HT activity would inhibit midbrain reticular activating system indirectly through non-serotonergic fibers, which in turn facilitate the onset or maintenance of hibernation.

  5. Research on Ajax and Hibernate technology in the development of E-shop system

    Science.gov (United States)

    Yin, Luo

    2011-12-01

    Hibernate is a object relational mapping framework of open source code, which conducts light-weighted object encapsulation of JDBC to let Java programmers use the concept of object-oriented programming to manipulate database at will. The appearence of the concept of Ajax (asynchronous JavaScript and XML technology) begins the time prelude of page partial refresh so that developers can develop web application programs with stronger interaction. The paper illustrates the concrete application of Ajax and Hibernate to the development of E-shop in details and adopts them to design to divide the entire program code into relatively independent parts which can cooperate with one another as well. In this way, it is easier for the entire program to maintain and expand.

  6. Six months of disuse during hibernation does not increase intracortical porosity or decrease cortical bone geometry, strength, or mineralization in black bear (Ursus americanus) femurs

    OpenAIRE

    McGee-Lawrence, Meghan E.; Wojda, Samantha J.; Barlow, Lindsay N.; Drummer, Thomas D.; Bunnell, Kevin; Auger, Janene; Black, Hal L.; Donahue, Seth W.

    2009-01-01

    Disuse typically uncouples bone formation from resorption, leading to bone loss which compromises bone mechanical properties and increases the risk of bone fracture. Previous studies suggest that bears can prevent bone loss during long periods of disuse (hibernation), but small sample sizes have limited the conclusions that can be drawn regarding the effects of hibernation on bone structure and strength in bears. Here we quantified the effects of hibernation on structural, mineral, and mechan...

  7. [Ornithine decarboxylase in mammalian organs and tissues at hibernation and artificial hypobiosis].

    Science.gov (United States)

    Logvinovich, O S; Aksenova, G E

    2013-01-01

    Ornithine decarboxylase (ODC, EC 4.1.1.17.) is a short-lived and dynamically regulated enzyme of polyamines biosynthesis. Regulation of functional, metabolic and proliferative state of organs and tissues involves the modifications of the ODC enzymatic activity. The organ-specific changes in ODC activity were revealed in organs and tissues (liver, spleen, bone marrow, kidney, and intestinal mucosa) of hibernating mammals - squirrels Spermophilus undulates - during the hibernating season. At that, a positive correlation was detected between the decline and recovery of the specialized functions of organs and tissues and the respective modifications of ODC activity during hibernation bouts. Investigation of changes in ODC activity in organs and tissues of non-hibernating mammals under artificial hypobiosis showed that in Wistar rats immediately after exposure to hypothermia-hypoxia-hypercapnia (hypobiosis) the level of ODC activity was low in thymus, spleen, small intestine mucosa, neocortex, and liver. The most marked reduction in enzyme activity was observed in actively proliferating tissues: thymus, spleen, small intestine mucosa. In bone marrow of squirrels, while in a state of torpor, as well as in thymus of rats after exposure to hypothermia-hypoxia-hypercapnia, changes in the ODC activity correlated with changes in the rate of cell proliferation (by the criterion of cells distribution over cell cycle). The results obtained, along with the critical analysis of published data, indicate that the ODC enzyme is involved in biochemical adaptation of mammals to natural and artificial hypobiosis. A decline in the ODC enzymatic activity indicates a decline in proliferative, functional, and metabolic activity of organs and tissues of mammals (bone marrow, mucosa of small intestine, thymus, spleen, neocortex, liver, kidneys) when entering the state of hypobiosis.

  8. What a hawkmoth remembers after hibernation depends on innate preferences and conditioning situation

    OpenAIRE

    Almut Kelber

    2010-01-01

    Nectar-feeding insects find flowers by 2 means, innate preferences and learned associations. When insects that hibernate as imagos (i.e., adults) start foraging after a long winter break, what guides them to new nectar rewards? Are innate preferences kept over such a long period? And are learned associations useful after long breaks? In a series of experiments I show here that, depending on previous experience, the European hummingbird hawkmoth, Macroglossum stellatarum can use both types of ...

  9. Grizzly bears exhibit augmented insulin sensitivity while obese prior to a reversible insulin resistance during hibernation.

    Science.gov (United States)

    Nelson, O Lynne; Jansen, Heiko T; Galbreath, Elizabeth; Morgenstern, Kurt; Gehring, Jamie Lauren; Rigano, Kimberly Scott; Lee, Jae; Gong, Jianhua; Shaywitz, Adam J; Vella, Chantal A; Robbins, Charles T; Corbit, Kevin C

    2014-08-05

    The confluence of obesity and diabetes as a worldwide epidemic necessitates the discovery of new therapies. Success in this endeavor requires translatable preclinical studies, which traditionally employ rodent models. As an alternative approach, we explored hibernation where obesity is a natural adaptation to survive months of fasting. Here we report that grizzly bears exhibit seasonal tripartite insulin responsiveness such that obese animals augment insulin sensitivity but only weeks later enter hibernation-specific insulin resistance (IR) and subsequently reinitiate responsiveness upon awakening. Preparation for hibernation is characterized by adiposity coupled to increased insulin sensitivity via modified PTEN/AKT signaling specifically in adipose tissue, suggesting a state of "healthy" obesity analogous to humans with PTEN haploinsufficiency. Collectively, we show that bears reversibly cope with homeostatic perturbations considered detrimental to humans and describe a mechanism whereby IR functions not as a late-stage metabolic adaptation to obesity, but rather a gatekeeper of the fed-fasting transition. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Hibernating black bears (Ursus americanus) experience skeletal muscle protein balance during winter anorexia.

    Science.gov (United States)

    Lohuis, T D; Harlow, H J; Beck, T D I

    2007-05-01

    Black bears spend four to seven months every winter confined to their den and anorexic. Despite potential for skeletal muscle atrophy and protein loss, bears appear to retain muscle integrity throughout winter dormancy. Other authors have suggested that bears are capable of net protein anabolism during this time. The present study was performed to test this hypothesis by directly measuring skeletal muscle protein metabolism during the summer, as well as early and late hibernation periods. Muscle biopsies were taken from the vastus lateralis of six free-ranging bears in the summer, and from six others early in hibernation and again in late winter. Protein synthesis and breakdown were measured on biopsies using (14)C-phenylalanine as a tracer. Muscle protein, nitrogen, and nucleic acid content, as well as nitrogen stable isotope enrichment, were also measured. Protein synthesis was greater than breakdown in summer bears, suggesting that they accumulate muscle protein during periods of seasonal food availability. Protein synthesis and breakdown were both lower in winter compared to summer but were equal during both early and late denning, indicating that bears are in protein balance during hibernation. Protein and nitrogen content, nucleic acid, and stable isotope enrichment measurements of the biopsies support this conclusion.

  11. Hibernation Site Philopatry in Northern Pine Snakes (Pituophis melanoleucus) in New Jersey

    Science.gov (United States)

    Burger, Joanna; Zappalorti, Robert

    2015-01-01

    Northern Pine Snakes (Pituophis melanoleucus) are one of the few snakes that spend the winter in underground hibernacula that they excavate. We report the use of hibernacula by Pine Snakes from 1986 to 2012 in the New Jersey Pine Barrens. We determined whether philopatry to a specific hibernaculum varied as a function of age, sex, and location of the hibernaculum. Three hibernacula were occupied nearly continuously for 27 yr by 1 to 27 snakes each year. With known-age snakes (N = 120), captured mainly as hatchlings and 2-yr-olds, we found that 23% were always philopatric. Philopatry was related to age of last capture, sex, and capture location. Philopatry was higher for 1) females compared with males, 2) snakes at two solitary hibernacula compared with a hibernaculum complex, and 3) snakes 6 yr old or younger, compared with older snakes. Of hatchlings found hibernating, 24% used the same hibernation site the next year, and 38% were located at year 4 or later. The number of snakes that always used the same hibernation site declined with the age of last capture. Snakes that entered hibernacula as hatchlings were found more often than those that entered as 2-yr-olds. For the seven snakes that were 14 yr or older, females were found 64– 86 % of the time, whereas males were found 15 to 50% of the time. Understanding the behavior and habitat requirements of snakes during different seasons is central to life-history analysis and for conserving viable populations. PMID:27011392

  12. White-nose syndrome increases torpid metabolic rate and evaporative water loss in hibernating bats.

    Science.gov (United States)

    McGuire, Liam P; Mayberry, Heather W; Willis, Craig K R

    2017-12-01

    Fungal diseases of wildlife typically manifest as superficial skin infections but can have devastating consequences for host physiology and survival. White-nose syndrome (WNS) is a fungal skin disease that has killed millions of hibernating bats in North America since 2007. Infection with the fungus Pseudogymnoascus destructans causes bats to rewarm too often during hibernation, but the cause of increased arousal rates remains unknown. On the basis of data from studies of captive and free-living bats, two mechanistic models have been proposed to explain disease processes in WNS. Key predictions of both models are that WNS-affected bats will show 1 ) higher metabolic rates during torpor (TMR) and 2 ) higher rates of evaporative water loss (EWL). We collected bats from a WNS-negative hibernaculum, inoculated one group with P. destructans , and sham-inoculated a second group as controls. After 4 mo of hibernation, TMR and EWL were measured using respirometry. Both predictions were supported, and our data suggest that infected bats were more affected by variation in ambient humidity than controls. Furthermore, disease severity, as indicated by the area of the wing with UV fluorescence, was positively correlated with EWL, but not TMR. Our results provide the first direct evidence that heightened energy expenditure during torpor and higher EWL independently contribute to WNS pathophysiology, with implications for the design of potential treatments for the disease. Copyright © 2017 the American Physiological Society.

  13. Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation.

    Science.gov (United States)

    Iaizzo, Paul A; Laske, Timothy G; Harlow, Henry J; McClay, Carolyn B; Garshelis, David L

    2012-03-01

    Even mildly hypothermic body or limb temperatures can retard healing processes in mammals. Despite this, we observed that hibernating American black bears (Ursus americanus Pallas, 1780) elicit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. In addition, they resolve injuries during hibernation while maintaining mildly hypothermic states (30-35 °C) and without eating, drinking, urinating or defecating. We describe experimental studies on free-ranging bears that document their abilities to completely resolve cutaneous cuts and punctures incurred during or prior to hibernation. We induced small, full-thickness cutaneous wounds (biopsies or incisions) during early denning, and re-biopsied sites 2-3 months later (near the end of denning). Routine histological methods were used to characterize these skin samples. All biopsied sites with respect to secondary intention (open circular biopsies) and primary intention (sutured sites) healed, with evidence of initial eschar (scab) formation, completeness of healed epidermis and dermal layers, dyskeratosis (inclusion cysts), and abilities to produce hair follicles. These healing abilities of hibernating black bears are a clear survival advantage to animals injured before or during denning. Bears are known to have elevated levels of hibernation induction trigger (delta-opioid receptor agonist) and ursodeoxycholic acid (major bile acid within plasma, mostly conjugated with taurine) during hibernation, which may relate to these wound-healing abilities. Further research as to the underlying mechanisms of wound healing during hibernation could have applications in human medicine. Unique approaches may be found to improve healing for malnourished, hypothermic, diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries. © 2012 ISZS, Blackwell Publishing and IOZ/CAS.

  14. Chilled frogs are hot: hibernation and reproduction of the Endangered mountain yellow-legged frog Rana muscosa

    Science.gov (United States)

    Santana, Frank E.; Swaisgood, Ronald R.; Lemm, Jeffrey M.; Fisher, Robert N.; Clark, Rulon W.

    2015-01-01

    In the face of the sixth great extinction crisis, it is imperative to establish effective breeding protocols for amphibian conservation breeding programs. Captive efforts should not proceed by trial and error, nor should they jump prematurely to assisted reproduction techniques, which can be invasive, difficult, costly, and, at times, counterproductive. Instead, conservation practitioners should first look to nature for guidance, and replicate key conditions found in nature in the captive environment, according to the ecological and behavioral requirements of the species. We tested the effect of a natural hibernation regime on reproductive behaviors and body condition in the Endangered mountain yellow-legged frog Rana muscosa. Hibernation had a clear positive effect on reproductive behavior, manifesting in vocal advertisement signaling, female receptivity, amplexus, and oviposition. These behaviors are critical components of courtship that lead to successful reproduction. Our main finding was that captive R. muscosa require a hibernation period for successful reproduction, as only hibernated females produced eggs and only hibernated males successfully fertilized eggs. Although hibernation also resulted in a reduced body condition, the reduction appeared to be minimal with no associated mortality. The importance of hibernation for reproduction is not surprising, since it is a major component of the conditions that R. muscosa experiences in the wild. Other amphibian conservation breeding programs can also benefit from a scientific approach that tests the effect of natural ecological conditions on reproduction. This will ensure that captive colonies maximize their role in providing genetic reservoirs for assurance and reintroduction efforts.

  15. Relationship of myocardial hibernation, scar, and angiographic collateral flow in ischemic cardiomyopathy with coronary chronic total occlusion.

    Science.gov (United States)

    Wang, Li; Lu, Min-Jie; Feng, Lei; Wang, Juan; Fang, Wei; He, Zuo-Xiang; Dou, Ke-Fei; Zhao, Shi-Hua; Yang, Min-Fu

    2018-03-07

    The relationship between myocardial viability and angiographic collateral flow is not fully elucidated in ischemic cardiomyopathy (ICM) with coronary artery chronic total occlusion (CTO). We aimed to clarify the relationship between myocardial hibernation, myocardial scar, and angiographic collateral flow in these patients. Seventy-one consecutive ICM patients with 122 CTOs and 652 dysfunctional segments within CTO territories were retrospectively analyzed. Myocardial hibernation (perfusion-metabolism mismatch) and the extent of 18 F-fluorodeoxyglucose (FDG) abnormalities were assessed using 99m Tc-sestamibi and 18 F-FDG imaging. Myocardial scar was evaluated by late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) imaging. Collateral flow observed on coronary angiography was assessed using Rentrop classification. In these patients, neither the extent nor frequency of myocardial hibernation or scar was related to the status of collateral flow. Moreover, the matching rate in determining myocardial viability was poor between any 2 imaging indices. The extent of 18 F-FDG abnormalities was linearly related to the extent of LGE rather than myocardial hibernation. Of note, nearly one-third (30.4%) of segments with transmural scar still had hibernating tissue. Hibernation and non-transmural scar had higher sensitivity (63.0% and 66.7%) than collateral flow (37.0%) in predicting global functional improvement. Angiographic collateral cannot accurately predict myocardial viability, and has lower sensitivity in prediction of functional improvement in CTO territories in ICM patients. Hence, assessment of myocardial viability with non-invasive imaging modalities is of importance. Moreover, due to the lack of correlation between myocardial hibernation and scar, these two indices are complementary but not interchangeable.

  16. Ca2+ cycling in heart cells from ground squirrels: adaptive strategies for intracellular Ca2+ homeostasis.

    Directory of Open Access Journals (Sweden)

    Xiao-Chen Li

    Full Text Available Heart tissues from hibernating mammals, such as ground squirrels, are able to endure hypothermia, hypoxia and other extreme insulting factors that are fatal for human and nonhibernating mammals. This study was designed to understand adaptive mechanisms involved in intracellular Ca(2+ homeostasis in cardiomyocytes from the mammalian hibernator, ground squirrel, compared to rat. Electrophysiological and confocal imaging experiments showed that the voltage-dependence of L-type Ca(2+ current (I(Ca was shifted to higher potentials in ventricular myocytes from ground squirrels vs. rats. The elevated threshold of I(Ca did not compromise the Ca(2+-induced Ca(2+ release, because a higher depolarization rate and a longer duration of action potential compensated the voltage shift of I(Ca. Both the caffeine-sensitive and caffeine-resistant components of cytosolic Ca(2+ removal were more rapid in ground squirrels. Ca(2+ sparks in ground squirrels exhibited larger amplitude/size and much lower frequency than in rats. Due to the high I(Ca threshold, low SR Ca(2+ leak and rapid cytosolic Ca(2+ clearance, heart cells from ground squirrels exhibited better capability in maintaining intracellular Ca(2+ homeostasis than those from rats and other nonhibernating mammals. These findings not only reveal adaptive mechanisms of hibernation, but also provide novel strategies against Ca(2+ overload-related heart diseases.

  17. Repeated functional convergent effects of NaV1.7 on acid insensitivity in hibernating mammals.

    Science.gov (United States)

    Liu, Zhen; Wang, Wei; Zhang, Tong-Zuo; Li, Gong-Hua; He, Kai; Huang, Jing-Fei; Jiang, Xue-Long; Murphy, Robert W; Shi, Peng

    2014-02-07

    Hibernating mammals need to be insensitive to acid in order to cope with conditions of high CO2; however, the molecular basis of acid tolerance remains largely unknown. The African naked mole-rat (Heterocephalus glaber) and hibernating mammals share similar environments and physiological features. In the naked mole-rat, acid insensitivity has been shown to be conferred by the functional motif of the sodium ion channel NaV1.7. There is now an opportunity to evaluate acid insensitivity in other taxa. In this study, we tested for functional convergence of NaV1.7 in 71 species of mammals, including 22 species that hibernate. Our analyses revealed a functional convergence of amino acid sequences, which occurred at least six times independently in mammals that hibernate. Evolutionary analyses determined that the convergence results from both parallel and divergent evolution of residues in the functional motif. Our findings not only identify the functional molecules responsible for acid insensitivity in hibernating mammals, but also open new avenues to elucidate the molecular underpinnings of acid insensitivity in mammals.

  18. Hibernating little brown myotis (Myotis lucifugus) show variable immunological responses to white-nose syndrome.

    Science.gov (United States)

    Moore, Marianne S; Reichard, Jonathan D; Murtha, Timothy D; Nabhan, Morgan L; Pian, Rachel E; Ferreira, Jennifer S; Kunz, Thomas H

    2013-01-01

    White-nose syndrome (WNS) is an emerging infectious disease devastating hibernating North American bat populations that is caused by the psychrophilic fungus Geomyces destructans. Previous histopathological analysis demonstrated little evidence of inflammatory responses in infected bats, however few studies have compared other aspects of immune function between WNS-affected and unaffected bats. We collected bats from confirmed WNS-affected and unaffected sites during the winter of 2008-2009 and compared estimates of their circulating levels of total leukocytes, total immunoglobulins, cytokines and total antioxidants. Bats from affected and unaffected sites did not differ in their total circulating immunoglobulin levels, but significantly higher leukocyte counts were observed in bats from affected sites and particularly in affected bats with elevated body temperatures (above 20°C). Bats from WNS-affected sites exhibited significantly lower antioxidant activity and levels of interleukin-4 (IL-4), a cytokine that induces T cell differentiation. Within affected sites only, bats exhibiting visible fungal infections had significantly lower antioxidant activity and levels of IL-4 compared to bats without visible fungal infections. Overall, bats hibernating in WNS-affected sites showed immunological changes that may be evident of attempted defense against G. destructans. Observed changes, specifically elevated circulating leukocytes, may also be related to the documented changes in thermoregulatory behaviors of affected bats (i.e. increased frequencies in arousal from torpor). Alterations in immune function may reflect expensive energetic costs associated with these processes and intrinsic qualities of the immunocapability of hibernating bats to clear fungal infections. Additionally, lowered antioxidant activity indicates a possible imbalance in the pro- versus antioxidant system, may reflect oxidative tissue damage, and should be investigated as a contributor to WNS

  19. Hibernating little brown myotis (Myotis lucifugus show variable immunological responses to white-nose syndrome.

    Directory of Open Access Journals (Sweden)

    Marianne S Moore

    Full Text Available White-nose syndrome (WNS is an emerging infectious disease devastating hibernating North American bat populations that is caused by the psychrophilic fungus Geomyces destructans. Previous histopathological analysis demonstrated little evidence of inflammatory responses in infected bats, however few studies have compared other aspects of immune function between WNS-affected and unaffected bats. We collected bats from confirmed WNS-affected and unaffected sites during the winter of 2008-2009 and compared estimates of their circulating levels of total leukocytes, total immunoglobulins, cytokines and total antioxidants. Bats from affected and unaffected sites did not differ in their total circulating immunoglobulin levels, but significantly higher leukocyte counts were observed in bats from affected sites and particularly in affected bats with elevated body temperatures (above 20°C. Bats from WNS-affected sites exhibited significantly lower antioxidant activity and levels of interleukin-4 (IL-4, a cytokine that induces T cell differentiation. Within affected sites only, bats exhibiting visible fungal infections had significantly lower antioxidant activity and levels of IL-4 compared to bats without visible fungal infections. Overall, bats hibernating in WNS-affected sites showed immunological changes that may be evident of attempted defense against G. destructans. Observed changes, specifically elevated circulating leukocytes, may also be related to the documented changes in thermoregulatory behaviors of affected bats (i.e. increased frequencies in arousal from torpor. Alterations in immune function may reflect expensive energetic costs associated with these processes and intrinsic qualities of the immunocapability of hibernating bats to clear fungal infections. Additionally, lowered antioxidant activity indicates a possible imbalance in the pro- versus antioxidant system, may reflect oxidative tissue damage, and should be investigated as a

  20. Miocárdio hibernante: uma realidade clínica Hibernant myocardium: a clinical reality

    Directory of Open Access Journals (Sweden)

    J.A. Marin-Neto

    1997-12-01

    Full Text Available O conceito da hibernação miocárdica implica a ocorrência de disfunção ventricular crônica, potencialmente reversível, causada por dissinergia regional, dependente de isquemia prolongada. Não tem fisiopatologia elucidada, em parte porque não existem modelos experimentais satisfatórios para seu estudo. Diversos métodos são capazes de demonstrar viabilidade miocárdica nas regiões que não exibem capacidade contrátil basal. O desmascaramento da hibernação nesses territórios pode ser feito mediante demonstração de reserva contrátil, de funcionamento normal da membrana celular, ou de metabolismo preservado. A correta identificação de miocárdio hibernante reveste-se de especial significado clínico, por suas implicações prognósticas quanto a intervenções de revascularização miocárdica, destinadas a reabilitar a função ventricular em muitos pacientes coronariopatas crônicos.Myocardial hibernation is believed to occur in ventricular dyssynergic regions chronically deprived of coronary flow enough to warrant the preservation of contractile function. Pathophysiology of this condition remains largely unclear, mainly because good experimental models for its study are still lacking. Various methods can be clinically employed to detect hibernation in patients with chronic ventricular dysfunction. These methods use the principle of unmasking contractile reserve, or are based on the demonstration of preserved membrane function or myocardium metabolism in the dyssynergic regions. The correct identification of viable hibernating myocardium is crucial in the process of deciding which coronary disease patients would potentially benefit from revascularization procedures.

  1. Effect of hibernation and reproductive status on body mass and condition of coastal brown bears

    Science.gov (United States)

    Hilderbrand, G.V.; Schwartz, C. C.; Robbins, C.T.; Hanley, Thomas A.

    2000-01-01

    We investigated the effect of hibernation and reproductive status on changes in body mass and composition of adult female brown bears (Ursus arctos) on the Kenai Peninsula, Alaska. This information is fundamental to understanding nutritional ecology of wild brown bear populations. Six adult females handled in the fall and following spring (paired samples) lost 73 ± 22 kg (x̄ ± SD; 32 ± 10%) of fall body mass over 208 ± 19 days. Of this mass loss, 56 ± 22% (55 ± 22 kg) was lipid and 44 ± 22% (43 ± 21 kg) was lean body mass. Catabolism of lipid stores accounted for 88.4 ± 8.1% of the body energy used to meet maintenance demands. Overwinter differences in body composition of adult females assessed only once in either the fall (n = 21) or spring (n = 32) were similar to those of paired samples. Relative fatness of bears entering the den was positively related to the contribution of fat (%) to body mass (P < 0.01) and body energy (P < 0.01) losses during hibernation. Thus, relative fatness at the onset of fasting influences the relative proportion of lipid stores and lean body mass catabolized to meet protein and energy demands during hibernation. In the spring, lone females had greater body and lean masses than females with cubs of the year or yearlings. Lipid content was greatest in lone females in the fall. Studies using body mass and composition as indices of population health should consider season or reproductive class.

  2. Effects of Multiple Routes of Cadmium Exposure on the Hibernation Success of the American Toad (Bufo americanus)

    Science.gov (United States)

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2004-01-01

    The effects of multiple routes of cadmium exposure on juvenile American toads (Bufo americanus) were evaluated using environmentally relevant concentrations. During or after exposure, toads were individually hibernated for 172 days at approximately 4??C. The following experiments were conducted: (1) dermal exposure (hibernation in soil contaminated with up to 120 ??g Cd/ g (dry weight)); (2) injection exposure (single injection with cadmium to achieve a maximum whole-body nominal concentration of 3 ??g Cd/g (wet weight) 12 days before hibernation in uncontaminated soil); and, (3) oral exposure (feeding with mealworms containing ???16 ??g Cd/g (dry weight) for 50 days before hibernation in uncontaminated soil)., We hypothesized that sublethal levels of cadmium would become lethal during hibernation because of combined chemical and cold stress. No prehibernation mortality occurred in the injection and oral exposure studies. There was a significant treatment effect on whole-body cadmium concentration in toads orally or dermally exposed and on percent of cadmium retention in toads orally exposed. There was also a trend of increased time-to-burrowing and more toads partially buried with greater cadmium concentration in the dermal study, which indicated avoidance. In all 3 experiments, no significant differences were found among cadmium treatments in hibernation survival, percent of mass loss, or locomotor performance. However, toads fed mealworms averaging 4.7 ??g Cd/g (dry weight) had only 56% survival compared with 100% survival for controls. Although our results suggest that environmentally relevant levels of cadmium do not pose a great risk to American toads, factors such as soil type or prey species may increase cadmium bioavailability, and other amphibian species may be more sensitive to cadmium than B. americanus.

  3. The effect of percutaneous transmyocardial laser revascularization on left ventricular function in a porcine model of hibernating myocardium

    International Nuclear Information System (INIS)

    Almeda, Francis Q.; Glock, Dana; Sandelski, Joanne; Ibrahim, Osama; Macioch, James E.; Allen, Trisha; Dainauskas, John R.; Parrillo, Joseph E.; Snell, R. Jeffrey; Schaer, Gary L.

    2004-01-01

    Background: Hibernating myocardium is defined as a state of persistently impaired myocardial function at rest due to reduced coronary blood flow that can partially or completely be restored to normal if the myocardial oxygen supply/demand relationship is favorably altered. Percutaneous laser revascularization (PMR) is an emerging catheter-based technique that involves creating channels in the myocardium, directly through a percutaneous approach with a laser delivery system, and has been shown to reduce symptoms in patients with severe refractory angina; however, its effect on improving regional wall motion abnormalities in hibernating myocardium has not been clearly established. We sought to determine the effect of PMR using the Eclipse System (Cardiogenesis) on left ventricular function in a porcine model of hibernating myocardium. Methods: A model of hibernating myocardium was created by placement of an ameroid constrictor in the proximal left anterior descending artery of a 35 kg male Yorkshire pig. The presence of hibernating myocardium was confirmed with dobutamine stress echocardiography (DSE) and defined as severe hypocontractility at rest, with an improvement in systolic wall thickening with low-dose dobutamine in myocardial regions with a subsequent deterioration in function at peak stress (biphasic response). After the demonstration of hibernating myocardium, PMR was performed in the area of hypocontractile function, and the serial echocardiography was performed. The echocardiograms were reviewed by an experienced echocardiologist blinded to the results, and regional wall motion was assessed using the American Society of Echocardiography Wall Motion Score. Six weeks after PMR, the animal was sacrificed and the heart sent for histopathologic studies. Results: A comparison of the regional wall motion function of the area distal to the ameroid constrictor and in the contralateral wall at baseline, post-ameroid placement, and post-PMR was performed

  4. White-nose syndrome fungus: a generalist pathogen of hibernating bats.

    Directory of Open Access Journals (Sweden)

    Jan Zukal

    Full Text Available Host traits and phylogeny can determine infection risk by driving pathogen transmission and its ability to infect new hosts. Predicting such risks is critical when designing disease mitigation strategies, and especially as regards wildlife, where intensive management is often advocated or prevented by economic and/or practical reasons. We investigated Pseudogymnoascus [Geomyces] destructans infection, the cause of white-nose syndrome (WNS, in relation to chiropteran ecology, behaviour and phylogenetics. While this fungus has caused devastating declines in North American bat populations, there have been no apparent population changes attributable to the disease in Europe. We screened 276 bats of 15 species from hibernacula in the Czech Republic over 2012 and 2013, and provided histopathological evidence for 11 European species positive for WNS. With the exception of Myotis myotis, the other ten species are all new reports for WNS in Europe. Of these, M. emarginatus, Eptesicus nilssonii, Rhinolophus hipposideros, Barbastella barbastellus and Plecotus auritus are new to the list of P. destructans-infected bat species. While the infected species are all statistically phylogenetically related, WNS affects bats from two suborders. These are ecologically diverse and adopt a wide range of hibernating strategies. Occurrence of WNS in distantly related bat species with diverse ecology suggests that the pathogen may be a generalist and that all bats hibernating within the distribution range of P. destructans may be at risk of infection.

  5. White-nose syndrome fungus: a generalist pathogen of hibernating bats.

    Science.gov (United States)

    Zukal, Jan; Bandouchova, Hana; Bartonicka, Tomas; Berkova, Hana; Brack, Virgil; Brichta, Jiri; Dolinay, Matej; Jaron, Kamil S; Kovacova, Veronika; Kovarik, Miroslav; Martínková, Natália; Ondracek, Karel; Rehak, Zdenek; Turner, Gregory G; Pikula, Jiri

    2014-01-01

    Host traits and phylogeny can determine infection risk by driving pathogen transmission and its ability to infect new hosts. Predicting such risks is critical when designing disease mitigation strategies, and especially as regards wildlife, where intensive management is often advocated or prevented by economic and/or practical reasons. We investigated Pseudogymnoascus [Geomyces] destructans infection, the cause of white-nose syndrome (WNS), in relation to chiropteran ecology, behaviour and phylogenetics. While this fungus has caused devastating declines in North American bat populations, there have been no apparent population changes attributable to the disease in Europe. We screened 276 bats of 15 species from hibernacula in the Czech Republic over 2012 and 2013, and provided histopathological evidence for 11 European species positive for WNS. With the exception of Myotis myotis, the other ten species are all new reports for WNS in Europe. Of these, M. emarginatus, Eptesicus nilssonii, Rhinolophus hipposideros, Barbastella barbastellus and Plecotus auritus are new to the list of P. destructans-infected bat species. While the infected species are all statistically phylogenetically related, WNS affects bats from two suborders. These are ecologically diverse and adopt a wide range of hibernating strategies. Occurrence of WNS in distantly related bat species with diverse ecology suggests that the pathogen may be a generalist and that all bats hibernating within the distribution range of P. destructans may be at risk of infection.

  6. Decreased bone turnover with balanced resorption and formation prevent cortical bone loss during disuse (hibernation) in grizzly bears (Ursus arctos horribilis).

    Science.gov (United States)

    McGee, Meghan E; Maki, Aaron J; Johnson, Steven E; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2008-02-01

    Disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. However, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. Here we show decreased cortical bone turnover during hibernation with balanced formation and resorption in grizzly bear femurs. Hibernating grizzly bear femurs were less porous and more mineralized, and did not demonstrate any changes in cortical bone geometry or whole bone mechanical properties compared to active grizzly bear femurs. The activation frequency of intracortical remodeling was 75% lower during hibernation than during periods of physical activity, but the normalized mineral apposition rate was unchanged. These data indicate that bone turnover decreases during hibernation, but osteons continue to refill at normal rates. There were no changes in regional variation of porosity, geometry, or remodeling indices in femurs from hibernating bears, indicating that hibernation did not preferentially affect one region of the cortex. Thus, grizzly bears prevent bone loss during disuse by decreasing bone turnover and maintaining balanced formation and resorption, which preserves bone structure and strength. These results support the idea that bears possess a biological mechanism to prevent disuse osteoporosis.

  7. Changes in expression of hepatic genes involved in energy metabolism during hibernation in captive, adult, female Japanese black bears (Ursus thibetanus japonicus).

    Science.gov (United States)

    Shimozuru, Michito; Kamine, Akari; Tsubota, Toshio

    2012-10-01

    Hibernating bears survive up to 6 months without feeding by utilizing stored body fat as fuel. To investigate how bears maintain energy homeostasis during hibernation, we analyzed changes in mRNA expression of hepatic genes involved in energy metabolism throughout the hibernation period in captive, adult, female Japanese black bears (Ursus thibetanus japonicus). Real-time PCR analysis revealed down-regulation of glycolysis- (e.g., glucokinase), amino acid catabolism- (e.g., alanine aminotransferase) and de novo lipogenesis-related genes (e.g., acetyl-CoA carboxylase 1), and up-regulation of gluconeogensis- (e.g., pyruvate carboxylase), β-oxidation- (i.e., uncoupling protein 2) and ketogenesis-related genes (i.e., 3-hydroxy-3-methylglutary-CoA synthase 2), during hibernation, compared to the active period (June). In addition, we found that glycolysis-related genes (i.e., glucokinase and pyruvate kinase) were more suppressed in the early phase of hibernation (January) compared to the late phase (March). One week after the commencement of feeding in April, expression levels of most genes returned to levels comparable to those seen in June, but β-oxidation-related genes were still up-regulated during this period. These results suggest that the modulation of gene expression is not static, but changes throughout the hibernation period. The transcriptional modulation during hibernation represents a unique physiological adaptation to prolonged fasting in bears. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. The effects of epidermal fatty acid profiles, 1-oleoglycerol, and triacylglycerols on the susceptibility of hibernating bats to Pseudogymnoascus destructans.

    Directory of Open Access Journals (Sweden)

    Melissa R Ingala

    Full Text Available White Nose Syndrome (WNS greatly increases the over-winter mortality of little brown (Myotis lucifugus, Indiana (M. sodalis, northern (M. septentrionalis, and tricolored (Perimyotis subflavus bats, and is caused by cutaneous infections with Pseudogymnoascus destructans (Pd. Big brown bats (Eptesicus fuscus are highly resistant to Pd infections. Seven different fatty acids (myristic, pentadecanoic, palmitic, palmitoleic, oleic, and, linoleic acids occur in the wing epidermis of both M. lucifugus and E. fuscus, 4 of which (myristic, palmitoleic, oleic, and, linoleic acids inhibit Pd growth. The amounts of myristic and linoleic acids in the epidermis of M. lucifugus decrease during hibernation, thus we predicted that the epidermal fatty acid profile of M. lucifugus during hibernation has a reduced ability to inhibit Pd growth. Laboratory Pd growth experiments were conducted to test this hypothesis. The results demonstrated that the fatty acid profile of M. lucifugus wing epidermis during hibernation has a reduced ability to inhibit the growth of Pd. Additional Pd growth experiments revealed that: a triacylglycerols composed of known anti-Pd fatty acids do not significantly affect growth, b pentadecanoic acid inhibits Pd growth, and c 1-oleoglycerol, which is found in the wing epidermis of E. fuscus, also inhibits the growth of this fungus. Analyses of white adipose from M. lucifugus also revealed the selective retention of oleic and linoleic acids in this tissue during hibernation.

  9. The effects of epidermal fatty acid profiles, 1-oleoglycerol, and triacylglycerols on the susceptibility of hibernating bats to Pseudogymnoascus destructans.

    Science.gov (United States)

    Ingala, Melissa R; Ravenelle, Rebecca E; Monro, Johanna J; Frank, Craig L

    2017-01-01

    White Nose Syndrome (WNS) greatly increases the over-winter mortality of little brown (Myotis lucifugus), Indiana (M. sodalis), northern (M. septentrionalis), and tricolored (Perimyotis subflavus) bats, and is caused by cutaneous infections with Pseudogymnoascus destructans (Pd). Big brown bats (Eptesicus fuscus) are highly resistant to Pd infections. Seven different fatty acids (myristic, pentadecanoic, palmitic, palmitoleic, oleic, and, linoleic acids) occur in the wing epidermis of both M. lucifugus and E. fuscus, 4 of which (myristic, palmitoleic, oleic, and, linoleic acids) inhibit Pd growth. The amounts of myristic and linoleic acids in the epidermis of M. lucifugus decrease during hibernation, thus we predicted that the epidermal fatty acid profile of M. lucifugus during hibernation has a reduced ability to inhibit Pd growth. Laboratory Pd growth experiments were conducted to test this hypothesis. The results demonstrated that the fatty acid profile of M. lucifugus wing epidermis during hibernation has a reduced ability to inhibit the growth of Pd. Additional Pd growth experiments revealed that: a) triacylglycerols composed of known anti-Pd fatty acids do not significantly affect growth, b) pentadecanoic acid inhibits Pd growth, and c) 1-oleoglycerol, which is found in the wing epidermis of E. fuscus, also inhibits the growth of this fungus. Analyses of white adipose from M. lucifugus also revealed the selective retention of oleic and linoleic acids in this tissue during hibernation.

  10. 99mTc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    International Nuclear Information System (INIS)

    Okada, David R.; Liu, Zhonglin; Johnson, Gerald; Okada, Robert D.; Beju, Delia; Khaw, Ban An

    2010-01-01

    99m Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine 99m Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). 99m Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. 99m Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 ± 0.09) (cpm, SEM) than in control (1.74 ± 0.07), stunned (1.68 ± 0.11), and hibernating (1.59 ± 0.11) (p 99m Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 ± 0.63) than in control (1.98 ± 0.15), stunned (1.79 ± 0.08), and hibernating (2.33 ± 0.15) (p 99m Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. 99m Tc-glucarate uptake was strongly correlated with myocardial necrosis as determined by three independent assessments of viability. There were minimal and similar 99m Tc-glucarate uptakes in control, stunned, and hibernating myocardium. (orig.)

  11. Capture, anesthesia, and disturbance of free-ranging brown bears (Ursus arctos) during hibernation.

    Science.gov (United States)

    Evans, Alina L; Sahlén, Veronica; Støen, Ole-Gunnar; Fahlman, Åsa; Brunberg, Sven; Madslien, Knut; Fröbert, Ole; Swenson, Jon E; Arnemo, Jon M

    2012-01-01

    We conducted thirteen immobilizations of previously collared hibernating two- to four-year-old brown bears (Ursus arctos) weighing 21-66 kg in central Sweden in winter 2010 and 2011 for comparative physiology research. Here we report, for the first time, an effective protocol for the capture and anesthesia of free-ranging brown bears during hibernation and an assessment of the disturbance the captures caused. Bears were darted in anthill, soil, or uprooted tree dens on eleven occasions, but two bears in rock dens fled and were darted outside the den. We used medetomidine at 0.02-0.06 mg/kg and zolazepam-tiletamine at 0.9-2.8 mg/kg for anesthesia. In addition, ketamine at 1.5 mg/kg was hand-injected intramuscularly in four bears and in six it was included in the dart at 1.1-3.0 mg/kg. Once anesthetized, bears were removed from the dens. In nine bears, arterial blood samples were analyzed immediately with a portable blood gas analyzer. We corrected hypoxemia in seven bears (PaO(2) 57-74 mmHg) with supplemental oxygen. We placed the bears back into the dens and antagonized the effect of medetomidine with atipamezole. Capturing bears in the den significantly increased the risk of den abandonment. One of twelve collared bears that were captured remained at the original den until spring, and eleven, left their dens (mean ± standard deviation) 3.2±3.6 (range 0.5-10.5) days after capture. They used 1.9±0.9 intermediate resting sites, during 6.2±7.8 days before entering a new permanent den. The eleven new permanent dens were located 730±589 m from the original dens. We documented that it was feasible and safe to capture hibernating brown bears, although they behaved differently than black bears. When doing so, researchers should use 25% of the doses used for helicopter darting during the active period and should consider increased energetic costs associated with den abandonment.

  12. Capture, anesthesia, and disturbance of free-ranging brown bears (Ursus arctos during hibernation.

    Directory of Open Access Journals (Sweden)

    Alina L Evans

    Full Text Available We conducted thirteen immobilizations of previously collared hibernating two- to four-year-old brown bears (Ursus arctos weighing 21-66 kg in central Sweden in winter 2010 and 2011 for comparative physiology research. Here we report, for the first time, an effective protocol for the capture and anesthesia of free-ranging brown bears during hibernation and an assessment of the disturbance the captures caused. Bears were darted in anthill, soil, or uprooted tree dens on eleven occasions, but two bears in rock dens fled and were darted outside the den. We used medetomidine at 0.02-0.06 mg/kg and zolazepam-tiletamine at 0.9-2.8 mg/kg for anesthesia. In addition, ketamine at 1.5 mg/kg was hand-injected intramuscularly in four bears and in six it was included in the dart at 1.1-3.0 mg/kg. Once anesthetized, bears were removed from the dens. In nine bears, arterial blood samples were analyzed immediately with a portable blood gas analyzer. We corrected hypoxemia in seven bears (PaO(2 57-74 mmHg with supplemental oxygen. We placed the bears back into the dens and antagonized the effect of medetomidine with atipamezole. Capturing bears in the den significantly increased the risk of den abandonment. One of twelve collared bears that were captured remained at the original den until spring, and eleven, left their dens (mean ± standard deviation 3.2±3.6 (range 0.5-10.5 days after capture. They used 1.9±0.9 intermediate resting sites, during 6.2±7.8 days before entering a new permanent den. The eleven new permanent dens were located 730±589 m from the original dens. We documented that it was feasible and safe to capture hibernating brown bears, although they behaved differently than black bears. When doing so, researchers should use 25% of the doses used for helicopter darting during the active period and should consider increased energetic costs associated with den abandonment.

  13. Conspecific disturbance contributes to altered hibernation patterns in bats with white-nose syndrome.

    Science.gov (United States)

    Turner, James M; Warnecke, Lisa; Wilcox, Alana; Baloun, Dylan; Bollinger, Trent K; Misra, Vikram; Willis, Craig K R

    2015-03-01

    The emerging wildlife disease white-nose syndrome (WNS) affects both physiology and behaviour of hibernating bats. Infection with the fungal pathogen Pseudogymnoascus destructans (Pd), the first pathogen known to target torpid animals, causes an increase in arousal frequency during hibernation, and therefore premature depletion of energy stores. Infected bats also show a dramatic decrease in clustering behaviour over the winter. To investigate the interaction between disease progression and torpor expression we quantified physiological (i.e., timing of arousal, rewarming rate) and behavioural (i.e., arousal synchronisation, clustering) aspects of rewarming events over four months in little brown bats (Myotis lucifugus) experimentally inoculated with Pd. We tested two competing hypotheses: 1) Bats adjust arousal physiology adaptively to help compensate for an increase in energetically expensive arousals. This hypothesis predicts that infected bats should increase synchronisation of arousals with colony mates to benefit from social thermoregulation and/or that solitary bats will exhibit faster rewarming rates than clustered individuals because rewarming costs fall as rewarming rate increases. 2) As for the increase in arousal frequency, changes in arousal physiology and clustering behaviour are maladaptive consequences of infection. This hypothesis predicts no effect of infection or clustering behaviour on rewarming rate and that disturbance by normothermic bats contributes to the overall increase in arousal frequency. We found that arousals of infected bats became more synchronised than those of controls as hibernation progressed but the pattern was not consistent with social thermoregulation. When a bat rewarmed from torpor, it was often followed in sequence by up to seven other bats in an arousal "cascade". Moreover, rewarming rate did not differ between infected and uninfected bats, was not affected by clustering and did not change over time. Our results support

  14. Hibernating bears (Ursidae): metabolic magicians of definite interest for the nephrologist.

    Science.gov (United States)

    Stenvinkel, Peter; Jani, Alkesh H; Johnson, Richard J

    2013-02-01

    Muscle loss, osteoporosis, and vascular disease are common in subjects with reduced renal function. Despite intensive research of the underlying risk factors and mechanisms driving these phenotypes, we still lack effective treatment strategies for this underserved patient group. Thus, new approaches are needed to identify effective treatments. We believe that nephrologists could learn much from biomimicry; i.e., studies of nature's models to solve complicated physiological problems and then imitate these fascinating solutions to develop novel interventions. The hibernating bear (Ursidae) should be of specific interest to the nephrologist as they ingest no food or water for months, remaining anuric and immobile, only to awaken with low blood urea nitrogen levels, healthy lean body mass, strong bones, and without evidence for thrombotic complications. Identifying the mechanisms by which bears prevent the development of azotemia, sarcopenia, osteoporosis, and atherosclerosis despite being inactive and anuric could lead to novel interventions for both prevention and treatment of patients with chronic kidney disease.

  15. Kronisk iskaemisk hjerteinsufficiens. Revaskularisering bedrer overlevelsen blandt patienter med hibernating myocardium

    DEFF Research Database (Denmark)

    Holdgaard, Paw Chr; Nielsen, Søren Steen; Wiggers, Henrik

    2007-01-01

    imaging was performed with 99mTc-sestamibi and glucose metabolism was visualized with 18F-fluorodeoxyglucose (18F-FDG) gamma camera PET. Medical records and death certificate were reviewed retrospectively. RESULTS: 50 patients were included. We found an increased survival among patients with HIB who......INTRODUCTION: Patients with ischemic heart failure and reversible dysfunctional myocardium (Hibernating myocardium, HIB) can benefit from revascularization. These patients can be selected with nuclear methods. The purpose of this study was to describe the results of the imaging procedures...... in patients tested for HIB and relate the results to the choice of treatment and cause of death. MATERIALS AND METHODS: During a 2-year period 51 patients were referred to determine the amount of HIB. This can be determined with blood flow and metabolic imaging of the heart. Resting-myocardial perfusion...

  16. Activation of stress signaling molecules in bat brain during arousal from hibernation.

    Science.gov (United States)

    Lee, Moonyong; Choi, Inho; Park, Kyoungsook

    2002-08-01

    Induction of glucose-regulated proteins (GRPs) is a ubiquitous intracellular response to stresses such as hypoxia, glucose starvation and acidosis. The induction of GRPs offers some protection against these stresses in vitro, but the specific role of GRPs in vivo remains unclear. Hibernating bats present a good in vivo model to address this question. The bats must overcome local high oxygen demand in tissue by severe metabolic stress during arousal thermogenesis. We used brain tissue of a temperate bat Rhinolopus ferrumequinum to investigate GRP induction by high metabolic oxygen demand and to identify associated signaling molecules. We found that during 30 min of arousal, oxygen consumption increased from nearly zero to 11.9/kg/h, which was about 8.7-fold higher than its active resting metabolic rate. During this time, body temperature rose from 7 degrees C to 35 degrees C, and levels of TNF-alpha and lactate in brain tissue increased 2-2.5-fold, indicating a high risk of oxygen shortage. Concomitantly, levels of GRP75, GRP78 and GRP94 increased 1.5-1.7-fold. At the same time, c-Jun N-terminal protein kinase (JNK) activity increased 6.4-fold, and extracellular signal-regulated protein kinase (ERK) activity decreased to a similar degree (6.1-fold). p38 MAPK activity was very low and remained unchanged during arousal. In addition, survival signaling molecules protein kinase B (Akt) and protein kinase C (PKC) were activated 3- and 5-fold, respectively, during arousal. Taken together, our results showed that bat brain undergoes high oxygen demand during arousal from hibernation. Up-regulation of GRP proteins and activation of JNK, PKCgamma and Akt may be critical for neuroprotection and the survival of bats during the repeated process.

  17. Provision of an air traffic control services in an airport environment : design and development of a Java application through the Hibernate persistence framework

    OpenAIRE

    Galduf Tel, Enrique

    2011-01-01

    Galduf Tel, E. (2010). Provision of an air traffic control services in an airport environment : design and development of a Java application through the Hibernate persistence framework. http://hdl.handle.net/10251/10161. Archivo delegado

  18. Hydrogen sulfide and nitric oxide metabolites in the blood of free-ranging brown bears and their potential roles in hibernation

    DEFF Research Database (Denmark)

    Revsbech, Inge G; Shen, Xinggui; Chakravarti, Ritu

    2014-01-01

    inhibitors of mitochondrial respiration, hydrogen sulfide (H2S) and nitric oxide (NO), in winter-hibernating and summer-active free-ranging Scandinavian brown bears. We found that levels of sulfide metabolites were overall similar in summer-active and hibernating bears but their composition in the plasma...... differed significantly, with a decrease in bound sulfane sulfur in hibernation. High levels of unbound free sulfide correlated with high levels of cysteine (Cys) and with low levels of bound sulfane sulfur, indicating that during hibernation H2S, in addition to being formed enzymatically from the substrate...... Cys, may also be regenerated from its oxidation products, including thiosulfate and polysulfides. In the absence of any dietary intake, this shift in the mode of H2S synthesis would help preserve free Cys for synthesis of glutathione (GSH), a major antioxidant found at high levels in the red blood...

  19. Objektově relační mapování s využitím frameworku Hibernate

    OpenAIRE

    Berger, Jan

    2013-01-01

    The bachelor's thesis Object-Relational Mapping with Framework Hibernate is primarily concerned with the description of problems of data persistence of programs written in Java programming language in relational databases. The tool for implementing persistence is object-relational mapping. In the first part of the thesis a concept of object-relational mapping is defined and some problems of its implementing are described. Then an example application is introduced, on which framework Hibernate...

  20. Decrease in the red cell cofactor 2,3-diphosphoglycerate increases hemoglobin oxygen affinity in the hibernating brown bear Ursus arctos.

    Science.gov (United States)

    Revsbech, Inge G; Malte, Hans; Fröbert, Ole; Evans, Alina; Blanc, Stéphane; Josefsson, Johan; Fago, Angela

    2013-01-01

    During winter hibernation, brown bears (Ursus arctos) reduce basal O(2) consumption rate to ∼25% compared with the active state, while body temperature decreases moderately (to ∼30°C), suggesting a temperature-independent component in their metabolic depression. To establish whether changes in O(2) consumption during hibernation correlate with changes in blood O(2) affinity, we took blood samples from the same six individuals of hibernating and nonhibernating free-ranging brown bears during winter and summer, respectively. A single hemoglobin (Hb) component was detected in all samples, indicating no switch in Hb synthesis. O(2) binding curves measured on red blood cell lysates at 30°C and 37°C showed a less temperature-sensitive O(2) affinity than in other vertebrates. Furthermore, hemolysates from hibernating bears consistently showed lower cooperativity and higher O(2) affinity than their summer counterparts, regardless of the temperature. We found that this increase in O(2) affinity was associated with a significant decrease in the red cell Hb-cofactor 2,3-diphosphoglycerate (DPG) during hibernation to approximately half of the summer value. Experiments performed on purified Hb, to which DPG had been added to match summer and winter levels, confirmed that the low DPG content was the cause of the left shift in the Hb-O(2) equilibrium curve during hibernation. Levels of plasma lactate indicated that glycolysis is not upregulated during hibernation and that metabolism is essentially aerobic. Calculations show that the increase in Hb-O(2) affinity and decrease in cooperativity resulting from decreased red cell DPG may be crucial in maintaining a fairly constant tissue oxygen tension during hibernation in vivo.

  1. Frequent arousal from hibernation linked to severity of infection and mortality in bats with white-nose syndrome.

    Directory of Open Access Journals (Sweden)

    DeeAnn M Reeder

    Full Text Available White-nose syndrome (WNS, an emerging infectious disease that has killed over 5.5 million hibernating bats, is named for the causative agent, a white fungus (Geomyces destructans (Gd that invades the skin of torpid bats. During hibernation, arousals to warm (euthermic body temperatures are normal but deplete fat stores. Temperature-sensitive dataloggers were attached to the backs of 504 free-ranging little brown bats (Myotis lucifugus in hibernacula located throughout the northeastern USA. Dataloggers were retrieved at the end of the hibernation season and complete profiles of skin temperature data were available from 83 bats, which were categorized as: (1 unaffected, (2 WNS-affected but alive at time of datalogger removal, or (3 WNS-affected but found dead at time of datalogger removal. Histological confirmation of WNS severity (as indexed by degree of fungal infection as well as confirmation of presence/absence of DNA from Gd by PCR was determined for 26 animals. We demonstrated that WNS-affected bats aroused to euthermic body temperatures more frequently than unaffected bats, likely contributing to subsequent mortality. Within the subset of WNS-affected bats that were found dead at the time of datalogger removal, the number of arousal bouts since datalogger attachment significantly predicted date of death. Additionally, the severity of cutaneous Gd infection correlated with the number of arousal episodes from torpor during hibernation. Thus, increased frequency of arousal from torpor likely contributes to WNS-associated mortality, but the question of how Gd infection induces increased arousals remains unanswered.

  2. Frequent arousal from hibernation linked to severity of infection and mortality in bats with white-nose syndrome.

    Science.gov (United States)

    Reeder, DeeAnn M; Frank, Craig L; Turner, Gregory G; Meteyer, Carol U; Kurta, Allen; Britzke, Eric R; Vodzak, Megan E; Darling, Scott R; Stihler, Craig W; Hicks, Alan C; Jacob, Roymon; Grieneisen, Laura E; Brownlee, Sarah A; Muller, Laura K; Blehert, David S

    2012-01-01

    White-nose syndrome (WNS), an emerging infectious disease that has killed over 5.5 million hibernating bats, is named for the causative agent, a white fungus (Geomyces destructans (Gd)) that invades the skin of torpid bats. During hibernation, arousals to warm (euthermic) body temperatures are normal but deplete fat stores. Temperature-sensitive dataloggers were attached to the backs of 504 free-ranging little brown bats (Myotis lucifugus) in hibernacula located throughout the northeastern USA. Dataloggers were retrieved at the end of the hibernation season and complete profiles of skin temperature data were available from 83 bats, which were categorized as: (1) unaffected, (2) WNS-affected but alive at time of datalogger removal, or (3) WNS-affected but found dead at time of datalogger removal. Histological confirmation of WNS severity (as indexed by degree of fungal infection) as well as confirmation of presence/absence of DNA from Gd by PCR was determined for 26 animals. We demonstrated that WNS-affected bats aroused to euthermic body temperatures more frequently than unaffected bats, likely contributing to subsequent mortality. Within the subset of WNS-affected bats that were found dead at the time of datalogger removal, the number of arousal bouts since datalogger attachment significantly predicted date of death. Additionally, the severity of cutaneous Gd infection correlated with the number of arousal episodes from torpor during hibernation. Thus, increased frequency of arousal from torpor likely contributes to WNS-associated mortality, but the question of how Gd infection induces increased arousals remains unanswered.

  3. Skin lesions in European hibernating bats associated with Geomyces destructans, the etiologic agent of white-nose syndrome.

    Science.gov (United States)

    Wibbelt, Gudrun; Puechmaille, Sébastien J; Ohlendorf, Bernd; Mühldorfer, Kristin; Bosch, Thijs; Görföl, Tamás; Passior, Karsten; Kurth, Andreas; Lacremans, Daniel; Forget, Frédéric

    2013-01-01

    White-nose syndrome (WNS) has claimed the lives of millions of hibernating insectivorous bats in North America. Its etiologic agent, the psychrophilic fungus Geomyces destructans, causes skin lesions that are the hallmark of the disease. The fungal infection is characterized by a white powdery growth on muzzle, ears and wing membranes. While WNS may threaten some species of North American bats with regional extinction, infection in hibernating bats in Europe seems not to be associated with significant mortality. We performed histopathological investigations on biopsy samples of 11 hibernating European bats, originating from 4 different countries, colonized by G. destructans. One additional bat was euthanized to allow thorough examination of multiple strips of its wing membranes. Molecular analyses of touch imprints, swabs and skin samples confirmed that fungal structures were G. destructans. Additionally, archived field notes on hibernacula monitoring data in the Harz Mountains, Germany, over an 11-year period (2000-2011) revealed multiple capture-recapture events of 8 banded bats repeatedly displaying characteristic fungal colonization. Skin lesions of G. destructans-affected hibernating European bats are intriguingly similar to the epidermal lesions described in North American bats. Nevertheless, deep invasion of fungal hyphae into the dermal connective tissue with resulting ulceration like in North American bats was not observed in the biopsy samples of European bats; all lesions found were restricted to the layers of the epidermis and its adnexae. Two bats had mild epidermal cupping erosions as described for North American bats. The possible mechanisms for any difference in outcomes of G. destructans infection in European and North American bats still need to be elucidated.

  4. Skin lesions in European hibernating bats associated with Geomyces destructans, the etiologic agent of white-nose syndrome.

    Directory of Open Access Journals (Sweden)

    Gudrun Wibbelt

    Full Text Available White-nose syndrome (WNS has claimed the lives of millions of hibernating insectivorous bats in North America. Its etiologic agent, the psychrophilic fungus Geomyces destructans, causes skin lesions that are the hallmark of the disease. The fungal infection is characterized by a white powdery growth on muzzle, ears and wing membranes. While WNS may threaten some species of North American bats with regional extinction, infection in hibernating bats in Europe seems not to be associated with significant mortality. We performed histopathological investigations on biopsy samples of 11 hibernating European bats, originating from 4 different countries, colonized by G. destructans. One additional bat was euthanized to allow thorough examination of multiple strips of its wing membranes. Molecular analyses of touch imprints, swabs and skin samples confirmed that fungal structures were G. destructans. Additionally, archived field notes on hibernacula monitoring data in the Harz Mountains, Germany, over an 11-year period (2000-2011 revealed multiple capture-recapture events of 8 banded bats repeatedly displaying characteristic fungal colonization. Skin lesions of G. destructans-affected hibernating European bats are intriguingly similar to the epidermal lesions described in North American bats. Nevertheless, deep invasion of fungal hyphae into the dermal connective tissue with resulting ulceration like in North American bats was not observed in the biopsy samples of European bats; all lesions found were restricted to the layers of the epidermis and its adnexae. Two bats had mild epidermal cupping erosions as described for North American bats. The possible mechanisms for any difference in outcomes of G. destructans infection in European and North American bats still need to be elucidated.

  5. The effects of hibernation and captivity on glucose metabolism and thyroid hormones in American black bear (Ursus americanus).

    Science.gov (United States)

    McCain, Stephanie; Ramsay, Ed; Kirk, Claudia

    2013-06-01

    American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined insulin and glucose tolerance tests and thyroid hormone profiles were performed on all bears during each stage. All three groups of bears had evidence of insulin resistance during the winter, as compared to the summer or fall, based on glucose tolerance curves. Analysis of thyroid hormone concentration varied and distinct patterns or similarities were not apparent. While obesity in captive American black bears is multifactorial, the finding that, regardless of their ability to hibernate, captive bears retain similar physiology to their wild counterparts indicates that captive bears' complex physiologic changes need to be addressed in their management.

  6. Thermoregulation and energetics in hibernating black bears: metabolic rate and the mystery of multi-day body temperature cycles.

    Science.gov (United States)

    Tøien, Øivind; Blake, John; Barnes, Brian M

    2015-05-01

    Black bears overwintering in outdoor hibernacula in Alaska decrease metabolism to as low as 25 % basal rates, while core body temperature (T(b)) decreases from 37 to 38 °C to a mid-hibernation average of 33 °C. T b develops cycles of 1.6-7.3 days length within a 30-36 °C range, with no circadian component. We do not know the mechanism or function underlying behind the T(b) cycles, although bears avoid T(b) of bears with body mass (BM) from 35.5 to 116.5 kg while recording T(b), metabolic rate (M), and shivering. T b cycle length (0.8-11.2 days) shortened as T den decreased (partial R(2) = 0.490, p bears with low thermal conductance (TC) showed more variation in T b cycle length with changes in T(den) than did smaller bears with high TC. Minimum T b across cycles was not consistent. At low T(den) bears shivered both during rising and decreasing phases of T(b) cycles, with minimum shivering during the fastest drop in T(b). At higher T den the T b pattern was more irregular. Mean M through T(b) cycles was negatively correlated to T den below lower critical temperatures (1.4-10.4 °C). Minimum M (0.3509 W/kg ± 0.0121 SE) during mid-hibernation scaled to BM [M (W) = 1.217 × BM (kg)(0.6979), R(2) = 0.855, p bears with high TC had the same T(b) cycle length as bears with low TC except at high T(den), thus not supporting the hypothesis that cooling rate alone determines T(b) cycle length. We conclude that T(b) cycling is effected by control of thermoregulatory heat production, and T(b) cycling may not be present when hibernating bears use passive thermoregulation. More intense shivering in the rising phase of cycles may contribute to the prevention of muscle disuse atrophy. Bears hibernating in cold conditions use more energy during hibernation than in warmer conditions. At T den below lower critical temperature, no extra energy expenditure results from T b cycling compared to keeping a stable T(b.)

  7. {sup 99m}Tc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    Energy Technology Data Exchange (ETDEWEB)

    Okada, David R. [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Liu, Zhonglin [University of Arizona School of Medicine, Tucson, AZ (United States); Johnson, Gerald; Okada, Robert D. [University of Oklahoma Health Sciences Center, Oklahoma, OK (United States); University of Tulsa, Tulsa, OK (United States); Beju, Delia [Oklahoma State University School of Medicine, Tulsa, OK (United States); Khaw, Ban An [Northeastern University, Boston, MA (United States)

    2010-10-15

    {sup 99m}Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine {sup 99m}Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). {sup 99m}Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. {sup 99m}Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 {+-} 0.09) (cpm, SEM) than in control (1.74 {+-} 0.07), stunned (1.68 {+-} 0.11), and hibernating (1.59 {+-} 0.11) (p < 0.05). Tracer retention curves for ischemic-reperfused were elevated at all time points as compared with the other groups. {sup 99m}Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 {+-} 0.63) than in control (1.98 {+-} 0.15), stunned (1.79 {+-} 0.08), and hibernating (2.33 {+-} 0.15) (p < 0.05). The 60-min well-counted tracer activity ratio of ischemic-reperfused to control was 9:1 and corroborated the NaI detector results. Creatine kinase, triphenyltetrazolium chloride, and electron microscopy all demonstrated significantly greater injury in ischemic-reperfused compared to the other groups. An excellent correlation was observed between viability markers and tracer activity (r = 0.99 triphenyltetrazolium chloride; r = 0.90 creatine kinase). {sup 99m}Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. {sup 99m}Tc-glucarate uptake was strongly correlated with myocardial necrosis as

  8. Persistence of a circadian rhythmicity for thyroid hormones in plasma and thyroid of hibernating male Rana ridibunda.

    Science.gov (United States)

    Kühn, E R; Delmotte, N M; Darras, V M

    1983-06-01

    The presence and circadian rhythmicity of thyroid hormones was studied in plasma and the thyroid gland of male Rana ridibunda before and during hibernation. Hibernating January frogs do have a lower T3 and T4 content of their thyroid gland whereas plasma levels of T3 are maintained and of T4 increased compared to fed September or October frogs. It seems likely that the increased photoperiod in January will be responsible for this increased T4 secretion, since controlled laboratory experiments performed in December did not reveal any influence of low temperature on circulating T3 or T4 levels. Also feeding does not influence circulating levels and thyroid content of thyroid hormones in frogs kept at room temperature during the month of January. A circadian rhythmicity of T3 and T4 in the thyroid gland is present in fed October frogs and in non fed December frogs acclimated at 5 degrees C for 12 days with an acrophase for T3 at approximately 1500 h and for T4 at around 1900 h, whereas in plasma only T3 does have circadian variations (acrophase about midnight) but not T4. When December frogs are acclimated to room temperature for 12 days, frogs are active again, but do not eat and have a lower body weight than frogs hibernating at 5 degrees C. Their T3 content of the thyroid gland has disappeared, but T4 thyroid content and plasma levels of T3 and T4 are maintained. As in hibernating frogs, no circadian variations in T4 plasma concentrations are present whereas the circadian thyroid T4 rhythm disappears. At the same time a dampening in rhythmicity for plasma T3 as judged by the significantly lower amplitude occurs. It is concluded that the persistence of circulating levels of thyroid hormones and of a circadian cyclicity for T3 in plasma in non feeding hibernating frogs may reflect the special metabolic state e.g. availability of food reserves in these animals.

  9. Comparative anatomical and ultrastructural features of the sensory papillae in the tongue of hibernating bats.

    Science.gov (United States)

    Azzali, G; Gabbi, C; Grandi, D; Arcari, M L

    1992-01-01

    The papillae of the tongue dorsal surface of the insectivorous, hibernating bats (Vespertilionidae and Rhinolophidae), whose function is mainly sensorial, consist of two circumvallate papillae, two foliate papillae, located at the side edges at the glossopalatine arch, and numerous fungiform papillae. The circumvallate and foliate papillae are characterized not only by their position, but also by presence of several taste buds which open through the external orifice of the gustatory canal into the cavity of the vallum, or furrow, which divides the two folds of the lingual mucosa. The fungiform papillae (extremely numerous on the whole dorsal surface) are characterized by an unusual arrangement (along 3 oblique lines on the anterior two-thirds and predominantly on the middle line of the tongue body) and by the presence of only one to three taste buds which open on the heavily keratinized dorsal epithelial surface. The taste buds are made up of sensory cells with a light or dark matrix; their apical cytoplasmic expansions are not found beyond the middle part of the gustatory canal, in contrast with the circumvallate and foliate papillae which protrude from the orifice of the gustatory pore. Comparisons with the papillae of other types of bats and Insectivora and evaluations of the morphological characteristics and their functional values (unusual areas of distribution of the papillae, apical cytoplasmic expansions and behaviour of microfolds observed under SEM) have been made in different environmental conditions and nutritional habits, with attention to the mechanical events in the course of feeding.

  10. Digestive enzymes in Rhinolophus euryale (Rhinolophidae, Chiroptera are active also during hibernation

    Directory of Open Access Journals (Sweden)

    Maxinová Edita

    2017-11-01

    Full Text Available During the winter, bats use hibernation as a means of surviving the period of low prey offer. However, the Mediterranean horseshoe bat (Rhinolophus euryale arouses from torpor quite frequently. Based on the actual climatic conditions, it can profit from occasional foraging oportunities, when they occur. We analysed faeces collected on four nights during the period from November 2012 to February 2013 from the Domica-Baradla cave system (Slovakia and Hungary. In mid-November, the largest proportion of faecal contents were from Lepidoptera. Later on, the proportion of non-consumptive mass in the faeces increased and prey remnants disappeared. We analysed the activity of digestive enzymes (amylase, chitobiase, endochitinase and glukosaminidase in faeces. The activity of these enzymes was detected in fresh faeces throughout the whole winter. The faecal activity of the chitinases was relatively stable during the monitored period, whilst the activity of amylase was highest during late November and December. Some level of active digestive enzymes during the winter could be an adaptation to occasional winter foraging.

  11. The behavioral energetics of New Zealand's bats: Daily torpor and hibernation, a continuum.

    Science.gov (United States)

    McNab, Brian K; O'Donnell, Colin

    2018-05-07

    We examine the impact of behavior on the short-term energy expenditures of the only terrestrial mammals endemic to New Zealand, two bats, the long-tailed (Chalinolobus tuberculatus, family Vespertilionidae), and the lesser short-tailed (Mystacina tuberculata, family Mystacinidae). Vespertilionidae has a world-wide distribution. Mystacinidae is restricted to New Zealand, although related to five neotropical families and one in Madagascar reflecting a shared Gondwanan origin of their Noctilionoidea superfamily. Both species have highly variable body temperatures and rates of metabolism. They feed on flying insects, which requires them to be torpid in shelters during cold, wet periods. In dry weather Mystacina is active in winter at ambient temperatures as low as -1.0 °C, foraging for terrestrial invertebrates in leaf litter, even in the presence of snow, and consuming fruit, nectar, and pollen from endemic plants that bloom in winter. The behavior of Mystacina expands its presence in a cool, wet, temperate forest in a manner unlike any other bat, another example of the distinctive characteristics of the endemic New Zealand fauna. The use of torpor generally depends on a series of factors, including body mass, ambient temperature, latitude, reproductive cycle, sociality, and fat deposits. These factors result in a diversity of responses that range along a continuum from short-term torpor to hibernation. Copyright © 2018. Published by Elsevier Inc.

  12. First direct evidence of long-distance seasonal movements and hibernation in a migratory bat

    Science.gov (United States)

    Weller, Theodore J.; Castle, Kevin T.; Liechti, Felix; Hein, Cris D.; Schirmacher, Michael R.; Cryan, Paul M.

    2016-01-01

    Understanding of migration in small bats has been constrained by limitations of techniques that were labor-intensive, provided coarse levels of resolution, or were limited to population-level inferences. Knowledge of movements and behaviors of individual bats have been unknowable because of limitations in size of tracking devices and methods to attach them for long periods. We used sutures to attach miniature global positioning system (GPS) tags and data loggers that recorded light levels, activity, and temperature to male hoary bats (Lasiurus cinereus). Results from recovered GPS tags illustrated profound differences among movement patterns by individuals, including one that completed a >1000 km round-trip journey during October 2014. Data loggers allowed us to record sub-hourly patterns of activity and torpor use, in one case over a period of 224 days that spanned an entire winter. In this latter bat, we documented 5 torpor bouts that lasted ≥16 days and a flightless period that lasted 40 nights. These first uses of miniature tags on small bats allowed us to discover that male hoary bats can make multi-directional movements during the migratory season and sometimes hibernate for an entire winter.

  13. Changes in body condition of hibernating bats support the thrifty female hypothesis and predict consequences for populations with white-nose syndrome.

    Science.gov (United States)

    Jonasson, Kristin A; Willis, Craig K R

    2011-01-01

    White-nose syndrome (WNS) is a new disease of bats that has devastated populations in eastern North America. Infection with the fungus, Geomyces destructans, is thought to increase the time bats spend out of torpor during hibernation, leading to starvation. Little is known about hibernation in healthy, free-ranging bats and more data are needed to help predict consequences of WNS. Trade-offs presumably exist between the energetic benefits and physiological/ecological costs of torpor, leading to the prediction that the relative importance of spring energy reserves should affect an individual's use of torpor and depletion of energy reserves during winter. Myotis lucifugus mate during fall and winter but females do not become pregnant until after spring emergence. Thus, female reproductive success depends on spring fat reserves while male reproductive success does not. Consequently, females should be "thrifty" in their use of fat compared to males. We measured body condition index (BCI; mass/forearm length) of 432 M. lucifugus in Manitoba, Canada during the winter of 2009/2010. Bats were captured during the fall mating period (n = 200), early hibernation (n = 125), and late hibernation (n = 128). Adult females entered hibernation with greater fat reserves and consumed those reserves more slowly than adult males and young of the year. Consequently, adult females may be more likely than males or young of the year to survive the disruption of energy balance associated with WNS, although surviving females may not have sufficient reserves to support reproduction.

  14. The effect of soil composition and hydration on the bioavailability and toxicity of cadmium to hibernating juvenile American toads (Bufo americanus)

    Science.gov (United States)

    James, Stacy M.; Little, Edward E.; Semlitsch, Raymond D.

    2004-01-01

    The soil ecotoxicology literature has focused primarily on a few major taxa, to the neglect of other fossorial organisms such as amphibians. We selected cadmium (Cd) and the American toad (Bufo americanus) as a model contaminant and biological species to assess the impact of soil contamination on amphibian hibernation survival and post-hibernation condition. Soil sand composition (50, 70, 90%) and hydration (100, 150% water holding capacity (WHC)) were manipulated in addition to Cd concentration (0, 56, 165, 483 μg/g) to determine whether these soil properties affect toxicity. Soil Cd concentration significantly reduced survival and locomotor performance, and was correlated negatively with percent mass loss and positively with whole body Cd concentration. Higher sand content resulted in less mass loss and greater Cd uptake. Toads that were hibernated in 50% sand hydrated to 100% WHC had higher survival, less mass loss, and better sprint performance than those hibernated in 50% sand, 150% WHC. This study demonstrates that concentrations of Cd found in soil at highly contaminated sites can be bioaccumulated by hibernating amphibians and may reduce fitness. Differences in microhabitat use may cause species to vary in their exposure and susceptibility to soil contamination. The toxicity of Cd to amphibians could be greater in natural systems where there are multiple stressors and fluctuations in environmental variables.

  15. Temperatures and locations used by hibernating bats, including Myotis sodalis (Indiana bat), in a limestone mine: implications for conservation and management.

    Science.gov (United States)

    Brack, Virgil

    2007-11-01

    Understanding temperatures used by hibernating bats will aid conservation and management efforts for many species. A limestone mine with 71 km of passages, used as a hibernaculum by approximately 30,000 bats, was visited four times during a 6-year period. The mine had been surveyed and mapped; therefore, bats could be precisely located and temperatures (T (s)) of the entire hibernaculum ceiling accurately mapped. It was predicted that bats should hibernate between 5 and 10 degrees C to (1) use temperatures that allow a near minimal metabolic rate, (2) maximize the duration of hibernation bouts, (3) avoid more frequent and prolonged arousal at higher temperatures, (4) avoid cold and freezing temperatures that require an increase in metabolism and a decrease in duration of hibernation bouts or that could cause death, and (5) balance benefits of a reduced metabolic rate and costs of metabolic depression. The distribution of each species was not random for location (P block walls and sheltered alcoves, which perhaps dampened air movement and temperature fluctuations. Myotis lucifugus (little brown myotis) hibernated in colder, more variable areas (X = 7.2 +/- 2.6 degrees C). Myotis septentrionalis (northern myotis), Pipistrellus subflavus (eastern pipistrelle), and Eptesicus fuscus (big brown bat) typically hibernated in warm, thermally stable areas (X = 9.1 +/- 0.2 degrees C, X = 9.6 +/- 1.9 degrees C, and X = 9.5 +/- 1.5 degrees C, respectively). These data do not indicate that hibernacula for M. sodalis, an endangered species, should be manipulated to cool below 5 degrees C.

  16. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    Energy Technology Data Exchange (ETDEWEB)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Mongillo, Marco; Khan, Muhammad T. [Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); Depre, Christophe [University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Cell Biology and Molecular Medicine, New Jersey, NJ (United States); University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Medicine, New Jersey, NJ (United States); Rimoldi, Ornella E. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); New York Medical College, Cardiovascular Research Institute, Department of Medicine, Valhalla, NY (United States); Camici, Paolo G. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom)

    2007-12-15

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([{sup 11}C]meta-hydroxy-ephedrine; HED) and {beta}-adrenoceptor ({beta}-AR) density ([{sup 11}C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V{sub d}) of HED in HM (47.95{+-}28.05 ml/g) and infarcted myocardium (42.69{+-}25.76 ml/g) was significantly reduced compared with controls (66.09{+-}14.48 ml/g). The V{sub d} of HED in normal myocardium (49.93{+-}20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial {beta}-AR density was significantly lower in HM (5.49{+-}2.35 pmol/g), infarcted (4.82{+-}2.61 pmol/g) and normal (5.86{+-}1.81 pmol/g) segments of patients compared with healthy controls (8.61{+-}1.32 pmol/g). Noradrenaline uptake-1 mechanism and {beta}-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  17. Effects of white-nose syndrome on regional population patterns of 3 hibernating bat species.

    Science.gov (United States)

    Ingersoll, Thomas E; Sewall, Brent J; Amelon, Sybill K

    2016-10-01

    Hibernating bats have undergone severe recent declines across the eastern United States, but the cause of these regional-scale declines has not been systematically evaluated. We assessed the influence of white-nose syndrome (an emerging bat disease caused by the fungus Pseudogymnoascus destructans, formerly Geomyces destructans) on large-scale, long-term population patterns in the little brown myotis (Myotis lucifugus), the northern myotis (Myotis septentrionalis), and the tricolored bat (Perimyotis subflavus). We modeled population trajectories for each species on the basis of an extensive data set of winter hibernacula counts of more than 1 million individual bats from a 4-state region over 13 years and with data on locations of hibernacula and first detections of white-nose syndrome at each hibernaculum. We used generalized additive mixed models to determine population change relative to expectations, that is, how population trajectories differed with a colony's infection status, how trajectories differed with distance from the point of introduction of white-nose syndrome, and whether declines were concordant with first local observation of the disease. Population trajectories in all species met at least one of the 3 expectations, but none met all 3. Our results suggest, therefore, that white-nose syndrome has affected regional populations differently than was previously understood and has not been the sole cause of declines. Specifically, our results suggest that in some areas and species, threats other than white-nose syndrome are also contributing to population declines, declines linked to white-nose syndrome have spread across large geographic areas with unexpected speed, and the disease or other threats led to declines in bat populations for years prior to disease detection. Effective conservation will require further research to mitigate impacts of white-nose syndrome, renewed attention to other threats to bats, and improved surveillance efforts to ensure

  18. Serratia myotis sp. nov. and Serratia vespertilionis sp. nov., isolated from bats hibernating in caves.

    Science.gov (United States)

    García-Fraile, P; Chudíčková, M; Benada, O; Pikula, J; Kolařík, M

    2015-01-01

    During the study of bacteria associated with bats affected by white-nose syndrome hibernating in caves in the Czech Republic, we isolated two facultatively anaerobic, Gram-stain-negative bacteria, designated strains 12(T) and 52(T). Strains 12(T) and 52(T) were motile, rod-like bacteria (0.5-0.6 µm in diameter; 1-1.3 µm long), with optimal growth at 20-35 °C and pH 6-8. On the basis of the almost complete sequence of their 16S rRNA genes they should be classified within the genus Serratia; the closest relatives to strains 12(T) and 52(T) were Serratia quinivorans DSM 4597(T) (99.5 % similarity in 16S rRNA gene sequences) and Serratia ficaria DSM 4569(T) (99.5% similarity in 16S rRNA gene sequences), respectively. DNA-DNA relatedness between strain 12(T) and S. quinivorans DSM 4597(T) was only 37.1% and between strain 52(T) and S. ficaria DSM 4569(T) was only 56.2%. Both values are far below the 70% threshold value for species delineation. In view of these data, we propose the inclusion of the two isolates in the genus Serratia as representatives of Serratia myotis sp. nov. (type strain 12(T) =CECT 8594(T) =DSM 28726(T)) and Serratia vespertilionis sp. nov. (type strain 52(T) =CECT 8595(T) =DSM 28727(T)). © 2015 IUMS.

  19. Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears.

    Science.gov (United States)

    Barrows, N D; Nelson, O L; Robbins, C T; Rourke, B C

    2011-01-01

    Grizzly bears (Ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. Left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. We evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (MyHC) isoform expression and expression of a set of genes important to muscle plasticity and mass regulation in the left atria and left ventricles of active and hibernating bears. We supplemented these data with measurements of systolic and diastolic function via echocardiography in unanesthetized grizzly bears. Atrial strain imaging revealed decreased atrial contractility, decreased expansion/reservoir function (increased atrial stiffness), and decreased passive-filling function (increased ventricular stiffness) in hibernating bears. Relative MyHC-α protein expression increased significantly in the atrium during hibernation. The left ventricle expressed 100% MyHC-β protein in both groups. Insulin-like growth factor (IGF-I) mRNA expression was reduced by ∼50% in both chambers during hibernation, consistent with the ventricular atrophy observed in these bears. Interestingly, mRNA expression of the atrophy-related ubiquitin ligases Muscle Atrophy F-box (MAFBx) and Muscle Ring Finger 1 did not increase, nor did expression of myostatin or hypoxia-inducible factor 1α (HIF-1α). We report atrium-specific decreases of 40% and 50%, respectively, in MAFBx and creatine kinase mRNA expression during hibernation. Decreased creatine kinase expression is consistent with lowered energy requirements and could relate to reduced atrial emptying function during hibernation. Taken together with our hemodynamic assessment, these data suggest a potential downregulation of atrial chamber function during hibernation to prevent fatigue and dilation

  20. Winter blood values of selected parameters in a group of non-hibernating captive brown bears (Ursus arctos).

    Science.gov (United States)

    Sergiel, A; Bednarski, M; Maślak, R; Piasecki, T; Huber, D

    2015-01-01

    Bears undergo some significant changes reflected in blood values during winter season. The most significant are reduced urea and increased creatinine, by some authors considered to be physiological indicators of hibernation. Studied group of six captive brown bears (Ursus arctos) showed decreased activity in winter but were accepting food and walked outdoors. Blood parameters assessed in February 2011 revealed mean values of leucocytes and neutrophils as significantly lower, and creatinine significantly increased compared to captive and free living bears sampled during other seasons when bears are active.

  1. Low cardiac output as physiological phenomenon in hibernating, free-ranging Scandinavian brown bears (Ursus arctos) - an observational study

    DEFF Research Database (Denmark)

    Jørgensen, Peter Godsk; Arnemo, Jon; Swenson, Jon E

    2014-01-01

    cardiac function associated with metabolic depression in the hibernating vs. active states in free-ranging Scandinavian brown bears. METHODS: We performed echocardiography on seven free-ranging brown bears in Dalarna, Sweden, anesthetized with medetomidine-zolazepam-tiletamine-ketamine during winter.......31) l/min vs. 3.54 (SD: 1.04) l/min (P=0.003), and mean cardiac index 0.63 (SD: 0.21) l/min/kg vs. 2.45 (SD: 0.52) l/min/ m2 (Pdisease...

  2. Grounded theory.

    Science.gov (United States)

    Harris, Tina

    2015-04-29

    Grounded theory is a popular research approach in health care and the social sciences. This article provides a description of grounded theory methodology and its key components, using examples from published studies to demonstrate practical application. It aims to demystify grounded theory for novice nurse researchers, by explaining what it is, when to use it, why they would want to use it and how to use it. It should enable nurse researchers to decide if grounded theory is an appropriate approach for their research, and to determine the quality of any grounded theory research they read.

  3. Pre-hibernation energy reserves in a temperate anuran, Rana chensinensis, along a relatively fine elevational gradient

    Science.gov (United States)

    Lu, X.; Li, B.; Li, Y.; Ma, X.; Fellers, G.M.

    2008-01-01

    Temperate anurans have energy substrates in the liver, fat bodies, carcass and gonads; these stores provide support for metabolism and egg production during hibernation, and for breeding activities in spring. This paper compares the energy budget shortly before hibernation among Rana chensinensis populations at elevations of 1400, 1700 and 2000 m along a river in northern China. The larger frogs, regardless of elevation, had relatively heavy storage organs and the masses of nearly all these organs were positively correlated with each other. After controlling for the effect of body size, we found no significant difference in energetic organ mass among different age classes for each of the three populations. There were sexual differences in energy strategy. Males in all populations accumulated greater reserves in liver, fat bodies and carcass than did females. In contrast, females put more energy into their ovaries and oviducts. Frogs from higher elevations tended to have heavier organs than those from lower elevations; however, the pattern did not vary systematically along fine environmental gradients. Mid-elevation R. chensinensis built up significantly more reserves than low-elevation individuals, but were similar to their highland conspecifics. Males from higher elevations tended to have heavier liver and fat bodies; females were similar in liver and ovary mass across all elevations, but formed heavier fat bodies, oviducts and somatic tissue at higher elevation sites.

  4. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    International Nuclear Information System (INIS)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J.; Mongillo, Marco; Khan, Muhammad T.; Depre, Christophe; Rimoldi, Ornella E.; Camici, Paolo G.

    2007-01-01

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([ 11 C]meta-hydroxy-ephedrine; HED) and β-adrenoceptor (β-AR) density ([ 11 C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V d ) of HED in HM (47.95±28.05 ml/g) and infarcted myocardium (42.69±25.76 ml/g) was significantly reduced compared with controls (66.09±14.48 ml/g). The V d of HED in normal myocardium (49.93±20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial β-AR density was significantly lower in HM (5.49±2.35 pmol/g), infarcted (4.82±2.61 pmol/g) and normal (5.86±1.81 pmol/g) segments of patients compared with healthy controls (8.61±1.32 pmol/g). Noradrenaline uptake-1 mechanism and β-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  5. Big data in wildlife research: remote web-based monitoring of hibernating black bears.

    Science.gov (United States)

    Laske, Timothy G; Garshelis, David L; Iaizzo, Paul A

    2014-12-11

    Numerous innovations for the management and collection of "big data" have arisen in the field of medicine, including implantable computers and sensors, wireless data transmission, and web-based repositories for collecting and organizing information. Recently, human clinical devices have been deployed in captive and free-ranging wildlife to aid in the characterization of both normal physiology and the interaction of animals with their environment, including reactions to humans. Although these devices have had a significant impact on the types and quantities of information that can be collected, their utility has been limited by internal memory capacities, the efforts required to extract and analyze information, and by the necessity to handle the animals in order to retrieve stored data. We surgically implanted miniaturized cardiac monitors (1.2 cc, Reveal LINQ™, Medtronic Inc.), a newly developed human clinical system, into hibernating wild American black bears (N = 6). These devices include wireless capabilities, which enabled frequent transmissions of detailed physiological data from bears in their remote den sites to a web-based data storage and management system. Solar and battery powered telemetry stations transmitted detailed physiological data over the cellular network during the winter months. The system provided the transfer of large quantities of data in near-real time. Observations included changes in heart rhythms associated with birthing and caring for cubs, and in all bears, long periods without heart beats (up to 16 seconds) occurred during each respiratory cycle. For the first time, detailed physiological data were successfully transferred from an animal in the wild to a web-based data collection and management system, overcoming previous limitations on the quantities of data that could be transferred. The system provides an opportunity to detect unusual events as they are occurring, enabling investigation of the animal and site shortly

  6. Detection of hibernating myocardium in patients with myocardial infarction by low-dose dobutamine echocardiography. Comparison with thallium-201 scintigraphy with reinjection

    International Nuclear Information System (INIS)

    Takagi, Tsutomu; Yoshikawa, Junichi; Yoshida, Kiyoshi; Akasaka, Takashi; Honda, Yasuhiro; Yonezawa, Yoshihiro; Shakudo, Masahiro

    1995-01-01

    The identification of hibernating myocardium is important for selecting patients who will benefit from coronary revascularization. The relationship between echocardiographic and radioisotopic markers of hibernating myocardium and postrevascularization recovery of myocardial function was investigated in 21 patients who underwent successful revascularization. Each patient underwent low-dose dobutamine stress echocardiography and thallium-201 ( 201 Tl) scintigraphy with reinjection before revascularization. The presence of contractile reserve in dobutamine stress echocardiography and Tl uptake in 201 Tl scintigraphy with reinjection were defined as markers of hibernating myocardium. Follow-up echocardiograms were evaluated for improved regional wall motion in all patients at a mean of 8.6 months after revascularization. Sensitivity, specificity, and positive and negative predictive values of low-dose dobutamine stress echocardiography for indicating recovery of function after revascularization were 75.0%, 77.8%, 81.8%, and 70.0%, respectively. Sensitivity, specificity, and positive and negative predictive values of 201 Tl scintigraphy with reinjection for indicating recovery of function after revascularization were 91.7%, 55.6%, 73.3%, and 83.3%, respectively. There were no statistical differences between low-dose dobutamine echocardiography and 201 Tl scintigraphy in predicting postrevascularization recovery of function in patients with hibernating myocardium. (author)

  7. Hemoglobin function and allosteric regulation in semi-fossorial rodents (family Sciuridae) with different altitudinal ranges

    Science.gov (United States)

    Revsbech, Inge G.; Tufts, Danielle M.; Projecto-Garcia, Joana; Moriyama, Hideaki; Weber, Roy E.; Storz, Jay F.; Fago, Angela

    2013-01-01

    SUMMARY Semi-fossorial ground squirrels face challenges to respiratory gas transport associated with the chronic hypoxia and hypercapnia of underground burrows, and such challenges are compounded in species that are native to high altitude. During hibernation, such species must also contend with vicissitudes of blood gas concentrations and plasma pH caused by episodic breathing. Here, we report an analysis of hemoglobin (Hb) function in six species of marmotine ground squirrels with different altitudinal distributions. Regardless of their native altitude, all species have high Hb–O2 affinities, mainly due to suppressed sensitivities to allosteric effectors [2,3-diphosphoglycerate (DPG) and chloride ions]. This suppressed anion sensitivity is surprising given that all canonical anion-binding sites are conserved. Two sciurid species, the golden-mantled and thirteen-lined ground squirrel, have Hb–O2 affinities that are characterized by high pH sensitivity and low thermal sensitivity relative to the Hbs of humans and other mammals. The pronounced Bohr effect is surprising in light of highly unusual amino acid substitutions at the C-termini that are known to abolish the Bohr effect in human HbA. Taken together, the high O2 affinity of sciurid Hbs suggests an enhanced capacity for pulmonary O2 loading under hypoxic and hypercapnic conditions, while the large Bohr effect should help to ensure efficient O2 unloading in tissue capillaries. In spite of the relatively low thermal sensitivities of the sciurid Hbs, our results indicate that the effect of hypothermia on Hb oxygenation is the main factor contributing to the increased blood–O2 affinity in hibernating ground squirrels. PMID:24172889

  8. White-nose syndrome-affected little brown myotis (Myotis lucifugus) increase grooming and other active behaviors during arousals from hibernation.

    Science.gov (United States)

    Brownlee-Bouboulis, Sarah A; Reeder, DeeAnn M

    2013-10-01

    White-nose syndrome (WNS) is an emerging infectious disease of hibernating bats linked to the death of an estimated 5.7 million or more bats in the northeastern United States and Canada. White-nose syndrome is caused by the cold-loving fungus Pseudogymnoascus destructans (Pd), which invades the skin of the muzzles, ears, and wings of hibernating bats. Previous work has shown that WNS-affected bats arouse to euthermic or near euthermic temperatures during hibernation significantly more frequently than normal and that these too-frequent arousals are tied to severity of infection and death date. We quantified the behavior of bats during these arousal bouts to understand better the causes and consequences of these arousals. We hypothesized that WNS-affected bats would display increased levels of activity (especially grooming) during their arousal bouts from hibernation compared to WNS-unaffected bats. Behavior of both affected and unaffected hibernating bats in captivity was monitored from December 2010 to March 2011 using temperature-sensitive dataloggers attached to the backs of bats and infrared motion-sensitive cameras. The WNS-affected bats exhibited significantly higher rates of grooming, relative to unaffected bats, at the expense of time that would otherwise be spent inactive. Increased self-grooming may be related to the presence of the fungus. Elevated activity levels in affected bats likely increase energetic stress, whereas the loss of rest (inactive periods when aroused from torpor) may jeopardize the ability of a bat to reestablish homeostasis in a number of physiologic systems.

  9. Six months of disuse during hibernation does not increase intracortical porosity or decrease cortical bone geometry, strength, or mineralization in black bear (Ursus americanus) femurs.

    Science.gov (United States)

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Bunnell, Kevin; Auger, Janene; Black, Hal L; Donahue, Seth W

    2009-07-22

    Disuse typically uncouples bone formation from resorption, leading to bone loss which compromises bone mechanical properties and increases the risk of bone fracture. Previous studies suggest that bears can prevent bone loss during long periods of disuse (hibernation), but small sample sizes have limited the conclusions that can be drawn regarding the effects of hibernation on bone structure and strength in bears. Here we quantified the effects of hibernation on structural, mineral, and mechanical properties of black bear (Ursus americanus) cortical bone by studying femurs from large groups of male and female bears (with wide age ranges) killed during pre-hibernation (fall) and post-hibernation (spring) periods. Bone properties that are affected by body mass (e.g. bone geometrical properties) tended to be larger in male compared to female bears. There were no differences (p>0.226) in bone structure, mineral content, or mechanical properties between fall and spring bears. Bone geometrical properties differed by less than 5% and bone mechanical properties differed by less than 10% between fall and spring bears. Porosity (fall: 5.5+/-2.2%; spring: 4.8+/-1.6%) and ash fraction (fall: 0.694+/-0.011; spring: 0.696+/-0.010) also showed no change (p>0.304) between seasons. Statistical power was high (>72%) for these analyses. Furthermore, bone geometrical properties and ash fraction (a measure of mineral content) increased with age and porosity decreased with age. These results support the idea that bears possess a biological mechanism to prevent disuse and age-related osteoporoses.

  10. Changes in body condition of hibernating bats support the thrifty female hypothesis and predict consequences for populations with white-nose syndrome.

    Directory of Open Access Journals (Sweden)

    Kristin A Jonasson

    Full Text Available White-nose syndrome (WNS is a new disease of bats that has devastated populations in eastern North America. Infection with the fungus, Geomyces destructans, is thought to increase the time bats spend out of torpor during hibernation, leading to starvation. Little is known about hibernation in healthy, free-ranging bats and more data are needed to help predict consequences of WNS. Trade-offs presumably exist between the energetic benefits and physiological/ecological costs of torpor, leading to the prediction that the relative importance of spring energy reserves should affect an individual's use of torpor and depletion of energy reserves during winter. Myotis lucifugus mate during fall and winter but females do not become pregnant until after spring emergence. Thus, female reproductive success depends on spring fat reserves while male reproductive success does not. Consequently, females should be "thrifty" in their use of fat compared to males. We measured body condition index (BCI; mass/forearm length of 432 M. lucifugus in Manitoba, Canada during the winter of 2009/2010. Bats were captured during the fall mating period (n = 200, early hibernation (n = 125, and late hibernation (n = 128. Adult females entered hibernation with greater fat reserves and consumed those reserves more slowly than adult males and young of the year. Consequently, adult females may be more likely than males or young of the year to survive the disruption of energy balance associated with WNS, although surviving females may not have sufficient reserves to support reproduction.

  11. Analyse dynamique de l'architecture de Hibernate en lien avec les stratégies de mapping

    OpenAIRE

    Goman, Dmitry; Dugerdil, Philippe

    2013-01-01

    Ce travail de Bachelor représente une étude des différentes stratégies de mapping objet/relationnel et le fonctionnement de l’architecture interne du framework Hibernate. Mon choix s’est orienté dans cette direction suite à une envie d’apprendre d’avantage sur cet outil largement utilisé dans le monde professionnel. L’idée est venue de l’intérêt que je porte pour la couche de persistance de données. La structure de ce travail est composée de quatre éléments essentiels : - Introduction aux mon...

  12. Hibernation impact on the catalytic activities of the mitochondrial D-3-hydroxybutyrate dehydrogenase in liver and brain tissues of jerboa (Jaculus orientalis

    Directory of Open Access Journals (Sweden)

    Hafiani Assia

    2003-09-01

    Full Text Available Abstract Background Jerboa (Jaculus orientalis is a deep hibernating rodent native to subdesert highlands. During hibernation, a high level of ketone bodies i.e. acetoacetate (AcAc and D-3-hydroxybutyrate (BOH are produced in liver, which are used in brain as energetic fuel. These compounds are bioconverted by mitochondrial D-3-hydroxybutyrate dehydrogenase (BDH E.C. 1.1.1.30. Here we report, the function and the expression of BDH in terms of catalytic activities, kinetic parameters, levels of protein and mRNA in both tissues i.e brain and liver, in relation to the hibernating process. Results We found that: 1/ In euthemic jerboa the specific activity in liver is 2.4- and 6.4- fold higher than in brain, respectively for AcAc reduction and for BOH oxidation. The same differences were found in the hibernation state. 2/ In euthermic jerboa, the Michaelis constants, KM BOH and KM NAD+ are different in liver and in brain while KM AcAc, KM NADH and the dissociation constants, KD NAD+and KD NADH are similar. 3/ During prehibernating state, as compared to euthermic state, the liver BDH activity is reduced by half, while kinetic constants are strongly increased except KD NAD+. 4/ During hibernating state, BDH activity is significantly enhanced, moreover, kinetic constants (KM and KD are strongly modified as compared to the euthermic state; i.e. KD NAD+ in liver and KM AcAc in brain decrease 5 and 3 times respectively, while KD NADH in brain strongly increases up to 5.6 fold. 5/ Both protein content and mRNA level of BDH remain unchanged during the cold adaptation process. Conclusions These results cumulatively explained and are consistent with the existence of two BDH enzymatic forms in the liver and the brain. The apoenzyme would be subjected to differential conformational folding depending on the hibernation state. This regulation could be a result of either post-translational modifications and/or a modification of the mitochondrial membrane state

  13. Distinct α subunit variations of the hypothalamic GABAA receptor triplets (αβγ are linked to hibernating state in hamsters

    Directory of Open Access Journals (Sweden)

    Alò Raffaella

    2010-09-01

    Full Text Available Abstract Background The structural arrangement of the γ-aminobutyric acid type A receptor (GABAAR is known to be crucial for the maintenance of cerebral-dependent homeostatic mechanisms during the promotion of highly adaptive neurophysiological events of the permissive hibernating rodent, i.e the Syrian golden hamster. In this study, in vitro quantitative autoradiography and in situ hybridization were assessed in major hypothalamic nuclei. Reverse Transcription Reaction-Polymerase chain reaction (RT-PCR tests were performed for specific GABAAR receptor subunit gene primers synthases of non-hibernating (NHIB and hibernating (HIB hamsters. Attempts were made to identify the type of αβγ subunit combinations operating during the switching ON/OFF of neuronal activities in some hypothalamic nuclei of hibernators. Results Both autoradiography and molecular analysis supplied distinct expression patterns of all α subunits considered as shown by a strong (p 1 ratio (over total α subunits considered in the present study in the medial preoptic area (MPOA and arcuate nucleus (Arc of NHIBs with respect to HIBs. At the same time α2 subunit levels proved to be typical of periventricular nucleus (Pe and Arc of HIB, while strong α4 expression levels were detected during awakening state in the key circadian hypothalamic station, i.e. the suprachiasmatic nucleus (Sch; 60%. Regarding the other two subunits (β and γ, elevated β3 and γ3 mRNAs levels mostly characterized MPOA of HIBs, while prevalently elevated expression concentrations of the same subunits were also typical of Sch, even though this time during the awakening state. In the case of Arc, notably elevated levels were obtained for β3 and γ2 during hibernating conditions. Conclusion We conclude that different αβγ subunits are operating as major elements either at the onset of torpor or during induction of the arousal state in the Syrian golden hamster. The identification of a brain regional

  14. Lammutada? Unustada? Uinutada? Rekonstrueerida? = Demolish? Forget? Hibernate? Reconstruct? / Tüüne-Kristin Vaikla

    Index Scriptorium Estoniae

    Vaikla, Tüüne-Kristin, 1961-

    2012-01-01

    13. Venezia arhitektuuribiennaalist "Ühisosa / Common ground" (kuraator David Chipperfield), mis annab võimaluse Eestil kaasa rääkida tänast arhitektuurimaailma puudutavatel olulistel teemadel. Eesti ekspositsioonist, mis käsitleb väärika modernismipärandi hääbumist Tallinna Linnahalli näitel

  15. Pronounced expression of the lipolytic inhibitor G0/G1 Switch Gene 2 (G0S2) in adipose tissue from brown bears (Ursus arctos) prior to hibernation

    DEFF Research Database (Denmark)

    Jessen, Niels; Nielsen, Thomas S; Vendelbo, Mikkel H

    2016-01-01

    Prior to hibernation, the brown bear (Ursus arctos) exhibits unparalleled weight gain. Unlike humans, weight gain in bears is associated with lower levels of circulating free fatty acids (FFA) and increased insulin sensitivity. Understanding how free-ranging brown bears suppress lipolysis when...... gaining weight may therefore provide novel insight toward the development of human therapies. Blood and subcutaneous adipose tissue were collected from immobilized free-ranging brown bears (fitted with GPS-collars) during hibernation in winter and from the same bears during the active period in summer...... in Dalarna, Sweden. The expression of lipid droplet-associated proteins in adipose tissue was examined under the hypothesis that bears suppress lipolysis during summer while gaining weight by increased expression of negative regulators of lipolysis. Adipose triglyceride lipase (ATGL) expression did...

  16. Body temperatures of hibernating little brown bats reveal pronounced behavioural activity during deep torpor and suggest a fever response during white-nose syndrome.

    Science.gov (United States)

    Mayberry, Heather W; McGuire, Liam P; Willis, Craig K R

    2018-03-01

    Hibernating animals use torpor [reduced body temperature (T b ) and metabolic rate] to reduce energy expenditure during winter. Periodic arousals to normal T b are energetically expensive, so hibernators trade off arousal benefits against energetic costs. This is especially important for bats with white-nose syndrome (WNS), a fungal disease causing increased arousal frequency. Little brown bats (Myotis lucifugus) with WNS show upregulation of endogenous pyrogens and sickness behaviour. Therefore, we hypothesized that WNS should cause a fever response characterized by elevated T b . Hibernators could also accrue some benefits of arousals with minimal T b increase, thus avoiding full arousal costs. We compared skin temperature (T sk ) of captive Myotis lucifugus inoculated with the WNS-causing fungus to T sk of sham-inoculated controls. Infected bats re-warmed to higher T sk during arousals which is consistent with a fever response. Torpid T sk did not differ. During what we term "cold arousals", bats exhibited movement following T sk increases of only 2.2 ± 0.3 °C, compared to >20 °C increases during normal arousals. Cold arousals occurred in both infected and control bats, suggesting they are not a pathophysiological consequence of WNS. Fever responses are energetically costly and could exacerbate energy limitation and premature fat depletion for bats with WNS. Cold arousals could represent an energy-saving mechanism for both healthy and WNS-affected bats when complete arousals are unnecessary or too costly. A few cold arousals were observed mid-hibernation, typically in response to disturbances. Cold arousals may, therefore, represent a voluntary restriction of arousal temperature instead of loss of thermoregulatory control.

  17. Reductions in mitochondrial O(2) consumption and preservation of high-energy phosphate levels after simulated ischemia in chronic hibernating myocardium.

    Science.gov (United States)

    Hu, Qingsong; Suzuki, Gen; Young, Rebeccah F; Page, Brian J; Fallavollita, James A; Canty, John M

    2009-07-01

    We performed the present study to determine whether hibernating myocardium is chronically protected from ischemia. Myocardial tissue was rapidly excised from hibernating left anterior descending coronary regions (systolic wall thickening = 2.8 +/- 0.2 vs. 5.4 +/- 0.3 mm in remote myocardium), and high-energy phosphates were quantified by HPLC during simulated ischemia in vitro (37 degrees C). At baseline, ATP (20.1 +/- 1.0 vs. 26.7 +/- 2.1 micromol/g dry wt, P < 0.05), ADP (8.1 +/- 0.4 vs. 10.3 +/- 0.8 micromol/g, P < 0.05), and total adenine nucleotides (31.2 +/- 1.3 vs. 40.1 +/- 2.9 micromol/g, P < 0.05) were depressed compared with normal myocardium, whereas total creatine, creatine phosphate, and ATP-to-ADP ratios were unchanged. During simulated ischemia, there was a marked attenuation of ATP depletion (5.6 +/- 0.9 vs. 13.7 +/- 1.7 micromol/g at 20 min in control, P < 0.05) and mitochondrial respiration [145 +/- 13 vs. 187 +/- 11 ng atoms O(2).mg protein(-1).min(-1) in control (state 3), P < 0.05], whereas lactate accumulation was unaffected. These in vitro changes were accompanied by protection of the hibernating heart from acute stunning during demand-induced ischemia. Thus, despite contractile dysfunction at rest, hibernating myocardium is ischemia tolerant, with reduced mitochondrial respiration and slowing of ATP depletion during simulated ischemia, which may maintain myocyte viability.

  18. Decreased bone turnover with balanced resorption and formation prevent cortical bone loss during disuse (hibernation) in grizzly bears (Ursus arctos horribilis)

    OpenAIRE

    McGee, Meghan E.; Maki, Aaron J.; Johnson, Steven E.; Lynne Nelson, O.; Robbins, Charles T.; Donahue, Seth W.

    2007-01-01

    Disuse uncouples bone formation from resorption, leading to increased porosity, decreased bone geometrical properties, and decreased bone mineral content which compromises bone mechanical properties and increases fracture risk. However, black bear bone properties are not adversely affected by aging despite annual periods of disuse (i.e., hibernation), which suggests that bears either prevent bone loss during disuse or lose bone and subsequently recover it at a faster rate than other animals. ...

  19. Ground water

    International Nuclear Information System (INIS)

    Osmond, J.K.; Cowart, J.B.

    1982-01-01

    The subject is discussed under the headings: background and theory (introduction; fractionation in the hydrosphere; mobility factors; radioisotope evolution and aquifer classification; aquifer disequilibria and geochemical fronts); case studies (introduction; (a) conservative, and (b) non-conservative, behaviour); ground water dating applications (general requirements; radon and helium; radium isotopes; uranium isotopes). (U.K.)

  20. Ground water

    International Nuclear Information System (INIS)

    Osmond, J.K.; Cowart, J.B.

    1992-01-01

    The great variations in concentrations and activity ratios of 234 U/ 238 U in ground waters and the features causing elemental and isotopic mobility in the hydrosphere are discussed. Fractionation processes and their application to hydrology and other environmental problems such as earthquake, groundwater and aquifer dating are described. (UK)

  1. Neuronal plasticity in hibernation and the proposed role of the microtubule-associated protein tau as a "master switch" regulating synaptic gain in neuronal networks.

    Science.gov (United States)

    Arendt, Thomas; Bullmann, Torsten

    2013-09-01

    The present paper provides an overview of adaptive changes in brain structure and learning abilities during hibernation as a behavioral strategy used by several mammalian species to minimize energy expenditure under current or anticipated inhospitable environmental conditions. One cellular mechanism that contributes to the regulated suppression of metabolism and thermogenesis during hibernation is reversible phosphorylation of enzymes and proteins, which limits rates of flux through metabolic pathways. Reversible phosphorylation during hibernation also affects synaptic membrane proteins, a process known to be involved in synaptic plasticity. This mechanism of reversible protein phosphorylation also affects the microtubule-associated protein tau, thereby generating a condition that in the adult human brain is associated with aggregation of tau protein to paired helical filaments (PHFs), as observed in Alzheimer's disease. Here, we put forward the concept that phosphorylation of tau is a neuroprotective mechanism to escape NMDA-mediated hyperexcitability of neurons that would otherwise occur during slow gradual cooling of the brain. Phosphorylation of tau and its subsequent targeting to subsynaptic sites might, thus, work as a kind of "master switch," regulating NMDA receptor-mediated synaptic gain in a wide array of neuronal networks, thereby enabling entry into torpor. If this condition lasts too long, however, it may eventually turn into a pathological trigger, driving a cascade of events leading to neurodegeneration, as in Alzheimer's disease or other "tauopathies".

  2. Forage preferences in two species of prairie dog (Cynomys parvidens and Cynomus ludovicianus): Implications for hibernation and facultative heterothermy

    Science.gov (United States)

    Lehmer, E.M.; Biggins, D.E.; Antolin, M.F.

    2006-01-01

    Several laboratory studies have shown that the ingestion of dietary linoleic (18:2 ??6) acid before winter can promote deep and continuous torpor, whereas excess consumption of ??-linolenic acid (18:3 ??3) can interfere with an animal's ability to reach and maintain low body temperatures during torpor. As mammalian heterotherms obtain linoleic and ??-linolenic acid strictly from the diet, diet selection has been proposed as a mechanism that allows hibernators to ingest levels of linoleic and ??-linolenic acid that promote favorable torpor patterns. Here diet, dietary nutrient content and patterns of forage preference of a representative hibernator, the Utah prairie dog Cynomys parvidens, and a facultative heterotherm, the black-tailed prairie dog Cynomys ludovicianus, were examined under natural field conditions. Diets of black-tailed (BTPD) and Utah prairie dogs (UTPD) differed across seasons (BTPD F26,108=9.59, Pplant species relative to their abundance on colonies in any season. Black-tailed prairie dogs did not consume or avoid consumption of plant species based on levels of total lipids, linoleic acid, ??-linolenic acid or nitrogen. Considering only the plants consumed, black-tailed prairie dogs appeared to prefer plants with low levels of ??-linolenic acid (F1,19=5.81, P=0.03), but there were no detectable relationships between preference and other nutrients. Utah prairie dogs consumed plants higher in ??-linolenic acid (t=1.98, P=0.05) and avoided plants high in linoleic acid (t=-2.02, P=0.04), but consumption-avoidance decisions did not appear to be related to nitrogen or total lipids. Of the plants consumed, Utah prairie dogs again preferred plants high in ??-linolenic acid (F1,17=4.62, P=0.05). Levels of linoleic and ??-linolenic acid were positively correlated in plants consumed by prairie dogs (BTPD Pearson r=0.66, P<0.01; UTPD Pearson r=0.79, P<0.01), reducing the opportunity for independent selection of either lipid. ?? 2006 The Authors.

  3. Ground Pollution Science

    International Nuclear Information System (INIS)

    Oh, Jong Min; Bae, Jae Geun

    1997-08-01

    This book deals with ground pollution science and soil science, classification of soil and fundamentals, ground pollution and human, ground pollution and organic matter, ground pollution and city environment, environmental problems of the earth and ground pollution, soil pollution and development of geological features of the ground, ground pollution and landfill of waste, case of measurement of ground pollution.

  4. Investigating and managing the rapid emergence of white-nose syndrome, a novel, fatal, infectious disease of hibernating bats.

    Science.gov (United States)

    Foley, Janet; Clifford, Deana; Castle, Kevin; Cryan, Paul; Ostfeld, Richard S

    2011-04-01

    White-nose syndrome (WNS) is a fatal disease of bats that hibernate. The etiologic agent of WNS is the fungus Geomyces destructans, which infects the skin and wing membranes. Over 1 million bats in six species in eastern North America have died from WNS since 2006, and as a result several species of bats may become endangered or extinct. Information is lacking on the pathogenesis of G. destructans and WNS, WNS transmission and maintenance, individual and site factors that contribute to the probability of an outbreak of WNS, and spatial dynamics of WNS spread in North America. We considered how descriptive and analytical epidemiology could be used to fill these information gaps, including a four-step (modified) outbreak investigation, application of a set of criteria (Hill's) for assessing causation, compartment models of disease dynamics, and spatial modeling. We cataloged and critiqued adaptive-management options that have been either previously proposed for WNS or were helpful in addressing other emerging diseases of wild animals. These include an ongoing program of prospective surveillance of bats and hibernacula for WNS, treatment of individual bats, increasing population resistance to WNS (through vaccines, immunomodulators, or other methods), improving probability of survival from starvation and dehydration associated with WNS, modifying hibernacula environments to eliminate G. destructans, culling individuals or populations, controlling anthropogenic spread of WNS, conserving genetic diversity of bats, and educating the public about bats and bat conservation issues associated with WNS. Conservation Biology ©2011 Society for Conservation Biology. No claim to original US government works.

  5. The fungus Trichophyton redellii sp. nov. causes skin infections that resemble white-nose syndrome of hibernating bats

    Science.gov (United States)

    Lorch, Jeffrey M.; Minnis, Andrew M.; Meteyer, Carol U.; Redell, Jennifer A.; White, J. Paul; Kaarakka, Heather M.; Muller, Laura K.; Lindner, David L.; Verant, Michelle L.; Shearn-Bochsler, Valerie I.; Blehert, David S.

    2014-01-01

    Before the discovery of white-nose syndrome (WNS), a fungal disease caused by Pseudogymnoascus destructans, there were no reports of fungal skin infections in bats during hibernation. In 2011, bats with grossly visible fungal skin infections similar in appearance to WNS were reported from multiple sites in Wisconsin, USA, a state outside the known range of P. destructans and WNS at that time. Tape impressions or swab samples were collected from affected areas of skin from bats with these fungal infections in 2012 and analyzed by microscopy, culture, or direct DNA amplification and sequencing of the fungal internal transcribed spacer region (ITS). A psychrophilic species ofTrichophyton was isolated in culture, detected by direct DNA amplification and sequencing, and observed on tape impressions. Deoxyribonucleic acid indicative of the same fungus was also detected on three of five bat carcasses collected in 2011 and 2012 from Wisconsin, Indiana, and Texas, USA. Superficial fungal skin infections caused by Trichophyton sp. were observed in histopathology for all three bats. Sequencing of the ITS of Trichophyton sp., along with its inability to grow at 25 C, indicated that it represented a previously unknown species, described herein as Trichophyton redellii sp. nov. Genetic diversity present within T. redellii suggests it is native to North America but that it had been overlooked before enhanced efforts to study fungi associated with bats in response to the emergence of WNS.

  6. [The coiled bodies and satellite microbodies of the oocyte nuclei in hibernating Rana temporaria frogs contain actin].

    Science.gov (United States)

    Tsvetkov, A G; Kvasov, I D; Khaĭtlina, S Iu; Parfenov, V N

    1997-01-01

    Immunocytochemical analysis of preparation of dispersed nuclei content in oocytes of III-IV stages of oogenesis, in terms of Dumont (1972), from hibernating grass frogs using monoclonal antibodies against actin, revealed two types of intranuclear structures containing this protein: coiled bodies (CB) and satellite microbodies (SM). Staining of these preparations with Rhodamin-phalloidin, known specifically to interact with fibrillar actin, did not reveal it in these structures. Results of our biochemical studies, using protease ESP32 specifically cutting only globular actin, are suggesting that both CB and SM contain globular actin. Gall et al. (1975) proposed that CB may be involved in assembling and sorting of small nuclear RNA for the three main RNA processing pathways: pre-mRNA splicing, pre-rRNA processing, and histone pre-mRNA 3'-end formation. Our finding of actin in CB allows a suggestion on actin involvement in the transport of RNA processing complexes from CB to some actual places where processing of RNA takes place. According to our previous data (Tsvetkov, Parfenov., 1994), SM participate in the karyosphere capsule formation. This process is preceded by SM fusion triggered presumably by actin.

  7. The fungus Trichophyton redellii sp. Nov. Causes skin infections that resemble white-nose syndrome of hibernating bats.

    Science.gov (United States)

    Lorch, Jeffrey M; Minnis, Andrew M; Meteyer, Carol U; Redell, Jennifer A; White, J Paul; Kaarakka, Heather M; Muller, Laura K; Lindner, Daniel L; Verant, Michelle L; Shearn-Bochsler, Valerie; Blehert, David S

    2015-01-01

    Before the discovery of white-nose syndrome (WNS), a fungal disease caused by Pseudogymnoascus destructans, there were no reports of fungal skin infections in bats during hibernation. In 2011, bats with grossly visible fungal skin infections similar in appearance to WNS were reported from multiple sites in Wisconsin, US, a state outside the known range of P. destructans and WNS at that time. Tape impressions or swab samples were collected from affected areas of skin from bats with these fungal infections in 2012 and analyzed by microscopy, culture, or direct DNA amplification and sequencing of the fungal internal transcribed spacer region (ITS). A psychrophilic species of Trichophyton was isolated in culture, detected by direct DNA amplification and sequencing, and observed on tape impressions. Deoxyribonucleic acid indicative of the same fungus was also detected on three of five bat carcasses collected in 2011 and 2012 from Wisconsin, Indiana, and Texas, US. Superficial fungal skin infections caused by Trichophyton sp. were observed in histopathology for all three bats. Sequencing of the ITS of Trichophyton sp., along with its inability to grow at 25 C, indicated that it represented a previously unknown species, described herein as Trichophyton redellii sp. nov. Genetic diversity present within T. redellii suggests it is native to North America but that it had been overlooked before enhanced efforts to study fungi associated with bats in response to the emergence of WNS.

  8. Dusky Cotton Bug Oxycarenus spp. (Hemiptera: Lygaeidae: Hibernating Sites and Management by using Plant Extracts under Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Abbas Muneer

    2015-09-01

    Full Text Available The dusky cotton bug, Oxycarenus spp., has now attained the status of a major pest of cotton crops that affects lint as well as the seed quality of cotton. Surveys were conducted to explore the hibernating sites in the districts Faisalabad, Multan and Bahawalpur. The efficacies of six different plant extracts, i.e. Neem (Azadirachta indica, Milkweed (Calotropis procera, Moringa (Moringa oleifera, Citrus (Citrus sinensis, Tobacco (Nicotiana tobacum and Castor (Ricinus communis were tested by using three different concentrations of each plant extract, i.e. 5, 2.5 and 1.5% under laboratory conditions at 25±2°C and 70±5% RH. The data were recorded 24, 48, 72 and 96 hours after treatment application. However, Psidium guajava, Azadirachta indica, Eucalyptus camaldulensis and Mangifera indica were graded as host plants heavily infested by Oxycarenus spp. Results (α≤0.05 indicated that increasing the concentration of extracts also increased the mortality. Nicotiana tobacum and Calotropis procera respectively displayed maximum 72 and 71, 84 and 80, 97 and 89% mortality at all concentrations, i.e. 1.25, 2.50 and 5.00%, after 96 hours of application. Two concentrations (2.5 and 5% are the most suitable for obtaining significant control of the dusky cotton bug.

  9. Investigating and managing the rapid emergence of white-nose syndrome, a novel, fatal, infectious disease of hibernating bats

    Science.gov (United States)

    Foley, Janet; Clifford, Deana; Castle, Kevin; Cryan, Paul M.; Ostfeld, Richard S.

    2011-01-01

    White-nose syndrome (WNS) is a fatal disease of bats that hibernate. The etiologic agent of WNS is the fungus Geomyces destructans, which infects the skin and wing membranes. Over 1 million bats in six species in eastern North America have died from WNS since 2006, and as a result several species of bats may become endangered or extinct. Information is lacking on the pathogenesis of G. destructans and WNS, WNS transmission and maintenance, individual and site factors that contribute to the probability of an outbreak of WNS, and spatial dynamics of WNS spread in North America. We considered how descriptive and analytical epidemiology could be used to fill these information gaps, including a four-step (modified) outbreak investigation, application of a set of criteria (Hill's) for assessing causation, compartment models of disease dynamics, and spatial modeling. We cataloged and critiqued adaptive-management options that have been either previously proposed for WNS or were helpful in addressing other emerging diseases of wild animals. These include an ongoing program of prospective surveillance of bats and hibernacula for WNS, treatment of individual bats, increasing population resistance to WNS (through vaccines, immunomodulators, or other methods), improving probability of survival from starvation and dehydration associated with WNS, modifying hibernacula environments to eliminate G. destructans, culling individuals or populations, controlling anthropogenic spread of WNS, conserving genetic diversity of bats, and educating the public about bats and bat conservation issues associated with WNS.

  10. Communication grounding facility

    International Nuclear Information System (INIS)

    Lee, Gye Seong

    1998-06-01

    It is about communication grounding facility, which is made up twelve chapters. It includes general grounding with purpose, materials thermal insulating material, construction of grounding, super strength grounding method, grounding facility with grounding way and building of insulating, switched grounding with No. 1A and LCR, grounding facility of transmission line, wireless facility grounding, grounding facility in wireless base station, grounding of power facility, grounding low-tenton interior power wire, communication facility of railroad, install of arrester in apartment and house, install of arrester on introduction and earth conductivity and measurement with introduction and grounding resistance.

  11. 'Grounded' Politics

    DEFF Research Database (Denmark)

    Schmidt, Garbi

    2012-01-01

    play within one particular neighbourhood: Nørrebro in the Danish capital, Copenhagen. The article introduces the concept of grounded politics to analyse how groups of Muslim immigrants in Nørrebro use the space, relationships and history of the neighbourhood for identity political statements....... The article further describes how national political debates over the Muslim presence in Denmark affect identity political manifestations within Nørrebro. By using Duncan Bell’s concept of mythscape (Bell, 2003), the article shows how some political actors idealize Nørrebro’s past to contest the present...... ethnic and religious diversity of the neighbourhood and, further, to frame what they see as the deterioration of genuine Danish identity....

  12. The White-Nose Syndrome Transcriptome: Activation of Anti-fungal Host Responses in Wing Tissue of Hibernating Little Brown Myotis.

    Science.gov (United States)

    Field, Kenneth A; Johnson, Joseph S; Lilley, Thomas M; Reeder, Sophia M; Rogers, Elizabeth J; Behr, Melissa J; Reeder, DeeAnn M

    2015-10-01

    White-nose syndrome (WNS) in North American bats is caused by an invasive cutaneous infection by the psychrophilic fungus Pseudogymnoascus destructans (Pd). We compared transcriptome-wide changes in gene expression using RNA-Seq on wing skin tissue from hibernating little brown myotis (Myotis lucifugus) with WNS to bats without Pd exposure. We found that WNS caused significant changes in gene expression in hibernating bats including pathways involved in inflammation, wound healing, and metabolism. Local acute inflammatory responses were initiated by fungal invasion. Gene expression was increased for inflammatory cytokines, including interleukins (IL) IL-1β, IL-6, IL-17C, IL-20, IL-23A, IL-24, and G-CSF and chemokines, such as Ccl2 and Ccl20. This pattern of gene expression changes demonstrates that WNS is accompanied by an innate anti-fungal host response similar to that caused by cutaneous Candida albicans infections. However, despite the apparent production of appropriate chemokines, immune cells such as neutrophils and T cells do not appear to be recruited. We observed upregulation of acute inflammatory genes, including prostaglandin G/H synthase 2 (cyclooxygenase-2), that generate eicosanoids and other nociception mediators. We also observed differences in Pd gene expression that suggest host-pathogen interactions that might determine WNS progression. We identified several classes of potential virulence factors that are expressed in Pd during WNS, including secreted proteases that may mediate tissue invasion. These results demonstrate that hibernation does not prevent a local inflammatory response to Pd infection but that recruitment of leukocytes to the site of infection does not occur. The putative virulence factors may provide novel targets for treatment or prevention of WNS. These observations support a dual role for inflammation during WNS; inflammatory responses provide protection but excessive inflammation may contribute to mortality, either by

  13. The White-Nose Syndrome Transcriptome: Activation of Anti-fungal Host Responses in Wing Tissue of Hibernating Little Brown Myotis.

    Directory of Open Access Journals (Sweden)

    Kenneth A Field

    2015-10-01

    Full Text Available White-nose syndrome (WNS in North American bats is caused by an invasive cutaneous infection by the psychrophilic fungus Pseudogymnoascus destructans (Pd. We compared transcriptome-wide changes in gene expression using RNA-Seq on wing skin tissue from hibernating little brown myotis (Myotis lucifugus with WNS to bats without Pd exposure. We found that WNS caused significant changes in gene expression in hibernating bats including pathways involved in inflammation, wound healing, and metabolism. Local acute inflammatory responses were initiated by fungal invasion. Gene expression was increased for inflammatory cytokines, including interleukins (IL IL-1β, IL-6, IL-17C, IL-20, IL-23A, IL-24, and G-CSF and chemokines, such as Ccl2 and Ccl20. This pattern of gene expression changes demonstrates that WNS is accompanied by an innate anti-fungal host response similar to that caused by cutaneous Candida albicans infections. However, despite the apparent production of appropriate chemokines, immune cells such as neutrophils and T cells do not appear to be recruited. We observed upregulation of acute inflammatory genes, including prostaglandin G/H synthase 2 (cyclooxygenase-2, that generate eicosanoids and other nociception mediators. We also observed differences in Pd gene expression that suggest host-pathogen interactions that might determine WNS progression. We identified several classes of potential virulence factors that are expressed in Pd during WNS, including secreted proteases that may mediate tissue invasion. These results demonstrate that hibernation does not prevent a local inflammatory response to Pd infection but that recruitment of leukocytes to the site of infection does not occur. The putative virulence factors may provide novel targets for treatment or prevention of WNS. These observations support a dual role for inflammation during WNS; inflammatory responses provide protection but excessive inflammation may contribute to mortality

  14. FROM CONVENIENT HIBERNATION TO CIRCUMSTANTIAL DESPERATION: HATE SPEECH, PARTY POLITICAL COMMUNICATION AND THE NIGERIA’S 2015 GENERAL ELECTIONS

    Directory of Open Access Journals (Sweden)

    Mike Omilusi

    2018-02-01

    Full Text Available Until a few months to the 2015 general elections, many political parties that have conveniently hibernated for a better part of their existence, perhaps owing to lack of proper organizational structure or support base, uncoordinated programmes or were registered because of pecuniary gains or admittance of anticipated poor electoral outing, suddenly began to jostle for political space. The main opposition party and the ruling party were either perfecting a merger processes or engulfed in internal wrangling such that communication with the electorate on fundamental issues became inconsequential. In fact, the two dominant parties, the Peoples Democratic Party and All Progressive Congress only produced their presidential candidates less than five months to the election; and the electoral campaign assumed desperate contestation in a climate of prejudice and intolerance. Hate speeches and violence were the hallmarks of their electoral campaigns. The 2015 general elections therefore, offer a unique context to interrogate the place of party political communication in an emerging democracy and specifically how hate campaigns among political gladiators/contending parties could generate violence, and if not tamed, derail democratic consolidation. This essay affirms that hate speech is not only inspired by some social circumstances but also part of a general democratic process. It attests to the fact that Nigerian politicians have become more desperate and daring in taking and retaining political power; and more intolerant of opposition, criticism and efforts at replacing them. Relying extensively on secondary sources with the aid of descriptive and narrative tools, this essay concludes that the political culture of a country determines the behavior and attitude of the population towards the political system and that democratic transition from one administration to another, particularly in emerging democracies, has often been accompanied by violence

  15. Inflammatory-induced hibernation in the fetus: priming of fetal sheep metabolism correlates with developmental brain injury.

    Directory of Open Access Journals (Sweden)

    Matthias Keller

    Full Text Available Prenatal inflammation is considered an important factor contributing to preterm birth and neonatal mortality and morbidity. The impact of prenatal inflammation on fetal bioenergetic status and the correlation of specific metabolites to inflammatory-induced developmental brain injury are unknown. We used a global metabolomics approach to examine plasma metabolites differentially regulated by intrauterine inflammation. Preterm-equivalent sheep fetuses were randomized to i.v. bolus infusion of either saline-vehicle or LPS. Blood samples were collected at baseline 2 h, 6 h and daily up to 10 days for metabolite quantification. Animals were killed at 10 days after LPS injection, and brain injury was assessed by histopathology. We detected both acute and delayed effects of LPS on fetal metabolism, with a long-term down-regulation of fetal energy metabolism. Within the first 3 days after LPS, 121 metabolites were up-regulated or down-regulated. A transient phase (4-6 days, in which metabolite levels recovered to baseline, was followed by a second phase marked by an opposing down-regulation of energy metabolites, increased pO(2 and increased markers of inflammation and ADMA. The characteristics of the metabolite response to LPS in these two phases, defined as 2 h to 2 days and at 6-9 days, respectively, were strongly correlated with white and grey matter volumes at 10 days recovery. Based on these results we propose a novel concept of inflammatory-induced hibernation of the fetus. Inflammatory priming of fetal metabolism correlated with measures of brain injury, suggesting potential for future biomarker research and the identification of therapeutic targets.

  16. Pathophysiology and diagnosis of hibernating myocardium in patients with post-ischemic heart failure. The contribution of PET

    International Nuclear Information System (INIS)

    Camici, P.G.; Rimoldi, O.E.

    2003-01-01

    Identification and treatment of hibernating myocardium (HM) lead to improvement in left ventricular (LV) function and prognosis in patients with post-ischemic heart failure. Different techniques are used to diagnose HM: echocardiography, MRI, SPECT and PET and, in patients with moderate LV impairment, their predictive values are similar. There are few data on patients with severe LV dysfunction and heart failure in whom the greatest benefits are apparent after revascularization. Quantification of FDG uptake with PET during hyperinsulinemic euglycemic clamp is accurate in these patients with the greatest mortality risk in whom other techniques may give high false negative rates. The debate on whether resting myocardial blood flow to HM is reduced or not has stimulated new research on heart failure in patients with coronary artery disease. PET with H 2 15 O or 13 NH 3 has been used for the absolute quantification of regional blood flow in human HM. When HM is properly identified, resting blood flow is not different from that in healthy volunteers although a reduction of ∼20% can be demonstrated in a minority of cases. PET studies have shown that the main feature of HM is a severe impairment of coronary vasodilator reserve that improves after revascularization in parallel with LV function. Thus, the pathophysiology of HM is more complex than initially postulated. The recent evidence that repetitive ischemia in patients can be cumulative and lead to more severe and prolonged stunning, lends further support to the hypothesis that, at least initially, stunning and HM are two facets of the same coin. (author)

  17. Growth promotion in pigs by oxytetracycline coincides with down regulation of serum inflammatory parameters and of hibernation-associated protein HP-27.

    Science.gov (United States)

    Soler, Laura; Miller, Ingrid; Hummel, Karin; Razzazi-Fazeli, Ebrahim; Jessen, Flemming; Escribano, Damian; Niewold, Theo

    2016-05-01

    The growth promoting effect of supplementing animal feed with antibiotics like tetracycline has traditionally been attributed to their antibiotic character. However, more evidence has been accumulated on their direct anti-inflammatory effect during the last two decades. Here we used a pig model to explore the systemic molecular effect of feed supplementation with sub therapeutic levels of oxytetracycline (OTC) by analysis of serum proteome changes. Results showed that OTC promoted growth, coinciding with a significant down regulation of different serum proteins related to inflammation, oxidation and lipid metabolism, confirming the anti-inflammatory mechanism of OTC. Interestingly, apart from the classic acute phase reactants also down regulation was seen of a hibernation associated plasma protein (HP-27), which is to our knowledge the first description in pigs. Although the exact function in non-hibernators is unclear, down regulation of HP-27 could be consistent with increased appetite, which is possibly linked to the anti-inflammatory action of OTC. Given that pigs are good models for human medicine due to their genetic and physiologic resemblance, the present results might also be used for rational intervention in human diseases in which inflammation plays an important role such as obesity, type 2 diabetes and cardiovascular diseases. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Pronounced expression of the lipolytic inhibitor G0/G1 Switch Gene 2 (G0S2) in adipose tissue from brown bears (Ursus arctos) prior to hibernation.

    Science.gov (United States)

    Jessen, Niels; Nielsen, Thomas S; Vendelbo, Mikkel H; Viggers, Rikke; Støen, Ole-Gunnar; Evans, Alina; Frøbert, Ole

    2016-04-01

    Prior to hibernation, the brown bear (Ursus arctos) exhibits unparalleled weight gain. Unlike humans, weight gain in bears is associated with lower levels of circulating free fatty acids (FFA) and increased insulin sensitivity. Understanding how free-ranging brown bears suppress lipolysis when gaining weight may therefore provide novel insight toward the development of human therapies. Blood and subcutaneous adipose tissue were collected from immobilized free-ranging brown bears (fitted with GPS-collars) during hibernation in winter and from the same bears during the active period in summer in Dalarna, Sweden. The expression of lipid droplet-associated proteins in adipose tissue was examined under the hypothesis that bears suppress lipolysis during summer while gaining weight by increased expression of negative regulators of lipolysis. Adipose triglyceride lipase (ATGL) expression did not differ between seasons, but in contrast, the expression of ATGL coactivator Comparative gene identification-58 (CGI-58) was lower in summer. In addition, the expression of the negative regulators of lipolysis, G0S2 and cell-death inducing DNA fragmentation factor-a-like effector (CIDE)C markedly increased during summer. Free-ranging brown bears display potent upregulation of inhibitors of lipolysis in adipose tissue during summer. This is a potential mechanism for increased insulin sensitivity during weight gain and G0S2 may serve as a target to modulate insulin sensitivity. © 2016 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  19. Ground water '89

    International Nuclear Information System (INIS)

    1989-01-01

    The proceedings of the 5th biennial symposium of the Ground Water Division of the Geological Society of South Africa are presented. The theme of the symposium was ground water and mining. Papers were presented on the following topics: ground water resources; ground water contamination; chemical analyses of ground water and mining and its influece on ground water. Separate abstracts were prepared for 5 of the papers presented. The remaining papers were considered outside the subject scope of INIS

  20. Do Peatlands Hibernate?

    Science.gov (United States)

    Dorrepaal, E.; Signarbieux, C.; Jassey, V.; Mills, R.; Buttler, A.; Robroek, B.

    2014-12-01

    Winter seasonality with extensive frost, snow cover and low incoming radiation characterise large areas at mid- and high latitudes, especially in mountain ranges and in the arctic. Given these adverse conditions, it is often assumed that ecosystem processes, such as plant photosynthesis, nutrient uptake and microbial activities, cease, or at best diminish to marginal rates compared to summer. However, snow is a good thermal insulator and a sufficiently thick snow cover might enable temperature-limited processes to continue in winter, especially belowground. Changes in winter precipitation may alter these conditions, yet, relative to the growing season, winter ecosystem processes remain poorly understood. We performed a snow-removal experiment on an ombrotrophic bog in the Swiss Jura mountains (1036 m.a.s.l.) to compare above- and belowground ecosystem processes with and without snow cover during mid- and late-winter (February and April) with the subsequent spring (June) and summer (July). The presence of 1m snow in mid-winter and 0.4m snow in late-winter strongly reduced the photosynthetic capacity (Amax) of Eriophorum vaginatum as well as the total microbial biomass compared to spring and summer values. Amax of Sphagnum magellanicum and uptake of 15N-labelled ammonium-nitrate by vascular plants were, however, almost as high or higher in mid- and late-winter as in summer. Snow removal increased the number of freeze-thaw cycles in mid-winter but also increased the minimum soil temperature in late-winter before ambient snow-melt. This strongly reduced all measured ecosystem processes in mid-winter compared to control and to spring and summer values. Plant 15N-uptake, Amax of Eriophorum and total microbial biomass returned to, or exceeded, control values soon before or after snowmelt. However, Sphagnum Amax and its length growth, as well as the structure of the microbial community showed clear carry-over effects of the reduced winter snow cover into next summer. Altogether, our data indicate that peatlands are active in winter. However, a continuous snow cover is crucial for ecosystem processes both in winter and in the subsequent summer and a reduction of snow thickness or duration due to climate change may impact on peatland ecosystem functioning at various levels.

  1. Ground water and energy

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  2. Electrical Subsurface Grounding Analysis

    International Nuclear Information System (INIS)

    J.M. Calle

    2000-01-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements

  3. The ground based plan

    International Nuclear Information System (INIS)

    1989-01-01

    The paper presents a report of ''The Ground Based Plan'' of the United Kingdom Science and Engineering Research Council. The ground based plan is a plan for research in astronomy and planetary science by ground based techniques. The contents of the report contains a description of:- the scientific objectives and technical requirements (the basis for the Plan), the present organisation and funding for the ground based programme, the Plan, the main scientific features and the further objectives of the Plan. (U.K.)

  4. Constructivist Grounded Theory?

    Directory of Open Access Journals (Sweden)

    Barney G. Glaser, PhD, Hon. PhD

    2012-06-01

    Full Text Available AbstractI refer to and use as scholarly inspiration Charmaz’s excellent article on constructivist grounded theory as a tool of getting to the fundamental issues on why grounded theory is not constructivist. I show that constructivist data, if it exists at all, is a very, very small part of the data that grounded theory uses.

  5. Communication, concepts and grounding

    NARCIS (Netherlands)

    van der Velde, Frank; van der Velde, F.

    2015-01-01

    This article discusses the relation between communication and conceptual grounding. In the brain, neurons, circuits and brain areas are involved in the representation of a concept, grounding it in perception and action. In terms of grounding we can distinguish between communication within the brain

  6. Rigour and grounded theory.

    Science.gov (United States)

    Cooney, Adeline

    2011-01-01

    This paper explores ways to enhance and demonstrate rigour in a grounded theory study. Grounded theory is sometimes criticised for a lack of rigour. Beck (1993) identified credibility, auditability and fittingness as the main standards of rigour for qualitative research methods. These criteria were evaluated for applicability to a Straussian grounded theory study and expanded or refocused where necessary. The author uses a Straussian grounded theory study (Cooney, In press) to examine how the revised criteria can be applied when conducting a grounded theory study. Strauss and Corbin (1998b) criteria for judging the adequacy of a grounded theory were examined in the context of the wider literature examining rigour in qualitative research studies in general and grounded theory studies in particular. A literature search for 'rigour' and 'grounded theory' was carried out to support this analysis. Criteria are suggested for enhancing and demonstrating the rigour of a Straussian grounded theory study. These include: cross-checking emerging concepts against participants' meanings, asking experts if the theory 'fit' their experiences, and recording detailed memos outlining all analytical and sampling decisions. IMPLICATIONS FOR RESEARCH PRACTICE: The criteria identified have been expressed as questions to enable novice researchers to audit the extent to which they are demonstrating rigour when writing up their studies. However, it should not be forgotten that rigour is built into the grounded theory method through the inductive-deductive cycle of theory generation. Care in applying the grounded theory methodology correctly is the single most important factor in ensuring rigour.

  7. [Introduction to grounded theory].

    Science.gov (United States)

    Wang, Shou-Yu; Windsor, Carol; Yates, Patsy

    2012-02-01

    Grounded theory, first developed by Glaser and Strauss in the 1960s, was introduced into nursing education as a distinct research methodology in the 1970s. The theory is grounded in a critique of the dominant contemporary approach to social inquiry, which imposed "enduring" theoretical propositions onto study data. Rather than starting from a set theoretical framework, grounded theory relies on researchers distinguishing meaningful constructs from generated data and then identifying an appropriate theory. Grounded theory is thus particularly useful in investigating complex issues and behaviours not previously addressed and concepts and relationships in particular populations or places that are still undeveloped or weakly connected. Grounded theory data analysis processes include open, axial and selective coding levels. The purpose of this article was to explore the grounded theory research process and provide an initial understanding of this methodology.

  8. Loģistikas pārvaldības sistēmas izstrāde, izmantojot Spring un Hibernate ietvarus

    OpenAIRE

    Ziļickis, Intars

    2009-01-01

    Kvalifikācijas darbā “Loģistikas pārvaldības sistēmas izstrāde, izmantojot Spring un Hibernate ietvarus” ir aprakstīta pogrammatūras izstrāde. Ir iekļauti programmatūras prasību un projektējumu aprakstoši dokumenti, dati par izstrādē izmantotajiem rīkiem un tehnoloģijām, kā arī aprakstīta programmatūras kvalitātes nodrošināšana, testēšana un darbietilpības aprēķins. Loģistikas pārvaldības sistēma ir paredzēta kompānijām, kas nodarbojas ar loģistikas pārvedumu izpildi, vieglākai pārve...

  9. The Grounded Theory Bookshelf

    Directory of Open Access Journals (Sweden)

    Vivian B. Martin, Ph.D.

    2005-03-01

    Full Text Available Bookshelf will provide critical reviews and perspectives on books on theory and methodology of interest to grounded theory. This issue includes a review of Heaton’s Reworking Qualitative Data, of special interest for some of its references to grounded theory as a secondary analysis tool; and Goulding’s Grounded Theory: A practical guide for management, business, and market researchers, a book that attempts to explicate the method and presents a grounded theory study that falls a little short of the mark of a fully elaborated theory.Reworking Qualitative Data, Janet Heaton (Sage, 2004. Paperback, 176 pages, $29.95. Hardcover also available.

  10. Hot Ground Vibration Tests

    Data.gov (United States)

    National Aeronautics and Space Administration — Ground vibration tests or modal surveys are routinely conducted to support flutter analysis for subsonic and supersonic vehicles. However, vibration testing...

  11. Efektivitas Instagram Common Grounds

    OpenAIRE

    Wifalin, Michelle

    2016-01-01

    Efektivitas Instagram Common Grounds merupakan rumusan masalah yang diambil dalam penelitian ini. Efektivitas Instagram diukur menggunakan Customer Response Index (CRI), dimana responden diukur dalam berbagai tingkatan, mulai dari awareness, comprehend, interest, intentions dan action. Tingkatan respons inilah yang digunakan untuk mengukur efektivitas Instagram Common Grounds. Teori-teori yang digunakan untuk mendukung penelitian ini yaitu teori marketing Public Relations, teori iklan, efekti...

  12. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  13. The Grounded Theory Bookshelf

    Directory of Open Access Journals (Sweden)

    Dr. Alvita Nathaniel, DSN, APRN, BC

    2005-06-01

    Full Text Available The Grounded Theory Perspective III: Theoretical Coding, Barney G. Glaser (Sociology Press, 2005. Not intended for a beginner, this book further defi nes, describes, and explicates the classic grounded theory (GT method. Perspective III lays out various facets of theoretical coding as Glaser meticulously distinguishes classic GT from other subsequent methods. Developed many years after Glaser’s classic GT, these methods, particularly as described by Strauss and Corbin, adopt the grounded theory name and engender ongoing confusion about the very premises of grounded theory. Glaser distinguishes between classic GT and the adscititious methods in his writings, referring to remodeled grounded theory and its offshoots as Qualitative Data Analysis (QDA models.

  14. Communication, concepts and grounding.

    Science.gov (United States)

    van der Velde, Frank

    2015-02-01

    This article discusses the relation between communication and conceptual grounding. In the brain, neurons, circuits and brain areas are involved in the representation of a concept, grounding it in perception and action. In terms of grounding we can distinguish between communication within the brain and communication between humans or between humans and machines. In the first form of communication, a concept is activated by sensory input. Due to grounding, the information provided by this communication is not just determined by the sensory input but also by the outgoing connection structure of the conceptual representation, which is based on previous experiences and actions. The second form of communication, that between humans or between humans and machines, is influenced by the first form. In particular, a more successful interpersonal communication might require forms of situated cognition and interaction in which the entire representations of grounded concepts are involved. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Stochastic ground motion simulation

    Science.gov (United States)

    Rezaeian, Sanaz; Xiaodan, Sun; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan

    2014-01-01

    Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensity measures such as spectral accelerations that are used in response-spectrum dynamic analysis. Despite the thousands of available strong ground motion records, there remains a shortage of records for large-magnitude earthquakes at short distances or in specific regions, as well as records that sample specific combinations of source, path, and site characteristics.

  16. Adding Theoretical Grounding to Grounded Theory: Toward Multi-Grounded Theory

    OpenAIRE

    Göran Goldkuhl; Stefan Cronholm

    2010-01-01

    The purpose of this paper is to challenge some of the cornerstones of the grounded theory approach and propose an extended and alternative approach for data analysis and theory development, which the authors call multi-grounded theory (MGT). A multi-grounded theory is not only empirically grounded; it is also grounded in other ways. Three different grounding processes are acknowledged: theoretical, empirical, and internal grounding. The authors go beyond the pure inductivist approach in GT an...

  17. Proteção do solo por plantas de cobertura de ciclo hibernal na região Sul do Brasil

    Directory of Open Access Journals (Sweden)

    Ana Regina Dahlem Ziech

    2015-05-01

    Full Text Available O objetivo deste trabalho foi avaliar o potencial de plantas de cobertura de ciclo hibernal na proteção do solo, na região Sudoeste do Paraná, em função da taxa de cobertura, da produção de matéria seca (MS, da relação C/N e da manutenção da MS remanescente dos resíduos vegetais na superfície do solo. Foram utilizados como cobertura do solo: aveia-preta (Avena strigosa, azevém (Lolium multiflorum, centeio (Secale cereale, tremoço-branco (Lupinus albus, ervilhaca comum (Vicia sativa, nabo forrageiro (Raphanus sativus e consórcios entre aveia-preta + ervilhaca comum (A+E e aveia-preta + ervilhaca comum + nabo forrageiro (A+E+N. O experimento foi avaliado durante os anos agrícolas 2010/2011 e 2011/2012. A decomposição das plantas de cobertura foi determinada com uso de bolsas de decomposição ("litter bags". A aveia-preta e os consórcios proporcionaram maiores taxas de cobertura do solo aos primeiros 50 dias após a semeadura, com aporte de MS superior a 2.600 kg ha-1 na superfície do solo. O consórcio entre A+E+N apresentou relação C/N equilibrada e decomposição intermediária em relação ao cultivo solteiro, tendo promovido 1.045 kg ha-1 de palhada sobre o solo, 120 dias após seu manejo. Gramíneas puras e consórcios com gramíneas apresentam maior potencial de proteção do solo

  18. Grounding of SNS Accelerator Structure

    CERN Document Server

    Holik, Paul S

    2005-01-01

    Description of site general grounding network. RF grounding network enhancement underneath the klystron gallery building. Grounding network of the Ring Systems with ground breaks in the Ring Tunnel. Grounding and Bonding of R&D accelerator equipment. SNS Building lightning protection.

  19. Airfield Ground Safety

    National Research Council Canada - National Science Library

    Petrescu, Jon

    2000-01-01

    .... The system developed under AGS, called the Ground Safety Tracking and Reporting System, uses multisensor data fusion from in-pavement inductive loop sensors to address a critical problem affecting out nation's airports: runway incursions...

  20. Grounded meets floating

    Science.gov (United States)

    Walker, Ryan T.

    2018-04-01

    A comprehensive assessment of grounding-line migration rates around Antarctica, covering a third of the coast, suggests retreat in considerable portions of the continent, beyond the rates expected from adjustment following the Last Glacial Maximum.

  1. Ground water and earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Ts' ai, T H

    1977-11-01

    Chinese folk wisdom has long seen a relationship between ground water and earthquakes. Before an earthquake there is often an unusual change in the ground water level and volume of flow. Changes in the amount of particulate matter in ground water as well as changes in color, bubbling, gas emission, and noises and geysers are also often observed before earthquakes. Analysis of these features can help predict earthquakes. Other factors unrelated to earthquakes can cause some of these changes, too. As a first step it is necessary to find sites which are sensitive to changes in ground stress to be used as sensor points for predicting earthquakes. The necessary features are described. Recording of seismic waves of earthquake aftershocks is also an important part of earthquake predictions.

  2. Yet Another Puzzle of Ground

    NARCIS (Netherlands)

    Korbmacher, J.

    2015-01-01

    We show that any predicational theory of partial ground that extends a standard theory of syntax and that proves some commonly accepted principles for partial ground is inconsistent. We suggest a way to obtain a consistent predicational theory of ground.

  3. Energy regulation in context: Free-living female arctic ground squirrels modulate the relationship between thyroid hormones and activity among life history stages.

    Science.gov (United States)

    Wilsterman, Kathryn; Buck, C Loren; Barnes, Brian M; Williams, Cory T

    2015-09-01

    Thyroid hormones (THs), key regulators of lipid and carbohydrate metabolism, are likely modulators of energy allocation within and among animal life history stages. Despite their role in modulating metabolism, few studies have investigated whether THs vary among life history stages in free-living animals or if they exhibit stage-specific relationships to total energy expenditure and activity levels. We measured plasma total triiodothyronine (tT3) and thyroxine (tT4) at four, discrete life history stages of female arctic ground squirrels from two different populations in northern Alaska to test whether plasma THs correlate with life history stage-specific changes in metabolic rate and energy demand. We also tested whether THs explained individual variation in aboveground activity levels within life history stages. T3 peaked during lactation and was lowest during pre-hibernation fattening, consistent with known changes in basal metabolism and core body temperature. In contrast, T4 was elevated shortly after terminating hibernation but remained low and stable across other life-history stages in the active season. THs were consistently higher in the population that spent more time above-ground but the relationship between THs and activity varied among life history stages. T3 was positively correlated with activity only during lactation (r(2)=0.50) whereas T4 was positively correlated with activity immediately following lactation (r(2)=0.48) and during fattening (r(2)=0.53). Our results support the hypothesis that THs are an important modulator of basal metabolism but also suggest that the relationship between THs and activity varies among life history stages. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Move of ground water

    International Nuclear Information System (INIS)

    Kimura, Shigehiko

    1983-01-01

    As a ground water flow which is difficult to explain by Darcy's theory, there is stagnant water in strata, which moves by pumping and leads to land subsidence. This is now a major problem in Japan. Such move on an extensive scale has been investigated in detail by means of 3 H such as from rainfall in addition to ordinary measurement. The move of ground water is divided broadly into that in an unsaturated stratum from ground surface to water-table and that in a saturated stratum below the water-table. The course of the analyses made so far by 3 H contained in water, and the future trend of its usage are described. A flow model of regarding water as plastic fluid and its flow as channel assembly may be available for some flow mechanism which is not possible to explain with Darcy's theory. (Mori, K.)

  5. Ground motion predictions

    Energy Technology Data Exchange (ETDEWEB)

    Loux, P C [Environmental Research Corporation, Alexandria, VA (United States)

    1969-07-01

    Nuclear generated ground motion is defined and then related to the physical parameters that cause it. Techniques employed for prediction of ground motion peak amplitude, frequency spectra and response spectra are explored, with initial emphasis on the analysis of data collected at the Nevada Test Site (NTS). NTS postshot measurements are compared with pre-shot predictions. Applicability of these techniques to new areas, for example, Plowshare sites, must be questioned. Fortunately, the Atomic Energy Commission is sponsoring complementary studies to improve prediction capabilities primarily in new locations outside the NTS region. Some of these are discussed in the light of anomalous seismic behavior, and comparisons are given showing theoretical versus experimental results. In conclusion, current ground motion prediction techniques are applied to events off the NTS. Predictions are compared with measurements for the event Faultless and for the Plowshare events, Gasbuggy, Cabriolet, and Buggy I. (author)

  6. Ground motion predictions

    International Nuclear Information System (INIS)

    Loux, P.C.

    1969-01-01

    Nuclear generated ground motion is defined and then related to the physical parameters that cause it. Techniques employed for prediction of ground motion peak amplitude, frequency spectra and response spectra are explored, with initial emphasis on the analysis of data collected at the Nevada Test Site (NTS). NTS postshot measurements are compared with pre-shot predictions. Applicability of these techniques to new areas, for example, Plowshare sites, must be questioned. Fortunately, the Atomic Energy Commission is sponsoring complementary studies to improve prediction capabilities primarily in new locations outside the NTS region. Some of these are discussed in the light of anomalous seismic behavior, and comparisons are given showing theoretical versus experimental results. In conclusion, current ground motion prediction techniques are applied to events off the NTS. Predictions are compared with measurements for the event Faultless and for the Plowshare events, Gasbuggy, Cabriolet, and Buggy I. (author)

  7. Graphene ground states

    Science.gov (United States)

    Friedrich, Manuel; Stefanelli, Ulisse

    2018-06-01

    Graphene is locally two-dimensional but not flat. Nanoscale ripples appear in suspended samples and rolling up often occurs when boundaries are not fixed. We address this variety of graphene geometries by classifying all ground-state deformations of the hexagonal lattice with respect to configurational energies including two- and three-body terms. As a consequence, we prove that all ground-state deformations are either periodic in one direction, as in the case of ripples, or rolled up, as in the case of nanotubes.

  8. Reduced expression of mitochondrial electron transport chain proteins from hibernating hearts relative to ischemic preconditioned hearts in the second window of protection.

    Science.gov (United States)

    Cabrera, Jesús A; Butterick, Tammy A; Long, Eric K; Ziemba, Elizabeth A; Anderson, Lorraine B; Duffy, Cayla M; Sluiter, Willem; Duncker, Dirk J; Zhang, Jianyi; Chen, Yingjie; Ward, Herbert B; Kelly, Rosemary F; McFalls, Edward O

    2013-07-01

    Although protection against necrosis has been observed in both hibernating (HIB) and ischemic preconditioned hearts in the second window of protection (SWOP), a comparison of the mitochondrial proteome between the two entities has not been previously performed. Anesthetized swine underwent instrumentation with a fixed constrictor around the LAD artery and were followed for 12 weeks (HIB; N=7). A second group of anesthetized swine underwent ischemic preconditioning by inflating a balloon within the LAD artery 10 times for 2 min, each separated by 2 min reperfusion and were sacrificed 24h later (SWOP; N=7). Myocardial blood flow and high-energy nucleotides were obtained in the LAD region and normalized to remote regions. Post-sacrifice, protein content as measured with iTRAQ was compared in isolated mitochondria from the LAD area of a Sham heart. Basal regional blood flow in the LAD region when normalized to the remote region was 0.86±0.04 in HIB and 1.02±0.02 in SWOP tissue (Pregional blood flows in HIB hearts, ATP content in the LAD region, when normalized to the remote region was similar in HIB versus SWOP (1.06±0.06 and 1.02±0.05 respectively; NS) as was the transmural phosphocreatine (PCr) to ATP ratio (2.1±0.2 and 2.2±0.2 respectively; NS). Using iTRAQ, 64 common proteins were identified in HIB and SWOP hearts. Compared with SWOP, the relative abundance of mitochondrial proteins involved with electron transport chain (ETC) were reduced in HIB including NADH dehydrogenase, Cytochrome c reductase and oxidase, ATP synthase, and nicotinamide nucleotide transhydrogenase. Within chronically HIB heart tissue with reduced blood flow, the relative abundance of mitochondrial ETC proteins is decreased when compared with SWOP tissue. These data support the concept that HIB heart tissue subjected to chronically reduced blood flow is associated with a down-regulation in the expression of key mitochondrial proteins involved in electron transport. Published by Elsevier

  9. Nuclear ground state

    International Nuclear Information System (INIS)

    Negele, J.W.

    1975-01-01

    The nuclear ground state is surveyed theoretically, and specific suggestions are given on how to critically test the theory experimentally. Detailed results on 208 Pb are discussed, isolating several features of the charge density distributions. Analyses of 208 Pb electron scattering and muonic data are also considered. 14 figures

  10. Informed Grounded Theory

    Science.gov (United States)

    Thornberg, Robert

    2012-01-01

    There is a widespread idea that in grounded theory (GT) research, the researcher has to delay the literature review until the end of the analysis to avoid contamination--a dictum that might turn educational researchers away from GT. Nevertheless, in this article the author (a) problematizes the dictum of delaying a literature review in classic…

  11. Mechanics of Ship Grounding

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    In these notes first a simplified mathematical model is presented for analysis of ship hull loading due to grounding on relatively hard and plane sand, clay or rock sea bottoms. In a second section a more rational calculation model is described for the sea bed soil reaction forces on the sea bott...

  12. Singlet Ground State Magnetism:

    DEFF Research Database (Denmark)

    Loidl, A.; Knorr, K.; Kjems, Jørgen

    1979-01-01

    The magneticGamma 1 –Gamma 4 exciton of the singlet ground state system TbP has been studied by inelastic neutron scattering above the antiferromagnetic ordering temperature. Considerable dispersion and a pronounced splitting was found in the [100] and [110] directions. Both the band width...

  13. Grounding Anger Management

    Directory of Open Access Journals (Sweden)

    Odis E. Simmons, PhD

    2017-06-01

    Full Text Available One of the things that drew me to grounded theory from the beginning was Glaser and Strauss’ assertion in The Discovery of Grounded Theory that it was useful as a “theoretical foothold” for practical applications (p. 268. From this, when I was a Ph.D student studying under Glaser and Strauss in the early 1970s, I devised a GT based approach to action I later came to call “grounded action.” In this short paper I’ll present a very brief sketch of an anger management program I developed in 1992, using grounded action. I began my research by attending a two-day anger management training workshop designed for training professionals in the most commonly used anger management model. Like other intervention programs I had seen, this model took a psychologizing and pathologizing approach to the issue. Following this, I sat through the full course of an anger management program that used this model, observing the reactions of the participants and the approach of the facilitator. Following each session I conducted open-ended interviews with most of the participants, either individually or in groups of two or three. I had also done previous research in counseling and social work contexts that turned out to be very relevant to an anger management program design.

  14. Grounding in Instant Messaging

    Science.gov (United States)

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  15. Collison and Grounding

    DEFF Research Database (Denmark)

    Wang, G.; Ji, C.; Kuhala, P.

    2006-01-01

    COMMITTEE MANDATE Concern for structural arrangements on ships and floating structures with regard to their integrity and adequacy in the events of collision and grounding, with the view towards risk assessment and management. Consideration shall be given to the frequency of occurrence...

  16. Infrasonic induced ground motions

    Science.gov (United States)

    Lin, Ting-Li

    On January 28, 2004, the CERI seismic network recorded seismic signals generated by an unknown source. Our conclusion is that the acoustic waves were initiated by an explosive source near the ground surface. The meteorological temperature and effective sound speed profiles suggested existence of an efficient near-surface waveguide that allowed the acoustic disturbance to propagate to large distances. An explosion occurring in an area of forest and farms would have limited the number of eyewitnesses. Resolution of the source might be possible by experiment or by detailed analysis of the ground motion data. A seismo-acoustic array was built to investigate thunder-induced ground motions. Two thunder events with similar N-wave waveforms but different horizontal slownesses are chosen to evaluate the credibility of using thunder as a seismic source. These impulsive acoustic waves excited P and S reverberations in the near surface that depend on both the incident wave horizontal slowness and the velocity structure in the upper 30 meters. Nineteen thunder events were chosen to further investigate the seismo-acoustic coupling. The consistent incident slowness differences between acoustic pressure and ground motions suggest that ground reverberations were first initiated somewhat away from the array. Acoustic and seismic signals were used to generate the time-domain transfer function through the deconvolution technique. Possible non-linear interaction for acoustic propagation into the soil at the surface was observed. The reverse radial initial motions suggest a low Poisson's ratio for the near-surface layer. The acoustic-to-seismic transfer functions show a consistent reverberation series of the Rayleigh wave type, which has a systematic dispersion relation to incident slownesses inferred from the seismic ground velocity. Air-coupled Rayleigh wave dispersion was used to quantitatively constrain the near-surface site structure with constraints afforded by near-surface body

  17. TOPEX ground data system

    Science.gov (United States)

    Rosell, S. N.; Yamarone, C. A., Jr.

    The TOPEX Project is a proposed oceanographic mission to measure the topography of the sea surface for a period of three years. This mission is sponsored by the National Aeronautics and Space Administration and managed by the Jet Propulsion Laboratory. Measurements of topography are used to study ocean currents, tides, bathymetry and the oceanic geoid. Several of the primary goals of this mission are to process and verify the altimetric data, and distribute them within days to the science investigators. This paper describes the TOPEX end-to-end ground data system. In addition to controlling the TOPEX satellite, the ground data system has been designed to minimize the time from data acquisition to science processing and data distribution. A centralized design supports the favorable response time of the system and also allows for operational efficiencies. Networking of real time and non-real time elements of the data system provides for more effective data processing.

  18. Ibis ground calibration

    International Nuclear Information System (INIS)

    Bird, A.J.; Barlow, E.J.; Tikkanen, T.; Bazzano, A.; Del Santo, M.; Ubertini, P.; Blondel, C.; Laurent, P.; Lebrun, F.; Di Cocco, G.; Malaguti, E.; Gabriele, M.; La Rosa, G.; Segreto, A.; Quadrini, E.; Volkmer, R.

    2003-01-01

    We present an overview of results obtained from IBIS ground calibrations. The spectral and spatial characteristics of the detector planes and surrounding passive materials have been determined through a series of calibration campaigns. Measurements of pixel gain, energy resolution, detection uniformity, efficiency and imaging capability are presented. The key results obtained from the ground calibration have been: - optimization of the instrument tunable parameters, - determination of energy linearity for all detection modes, - determination of energy resolution as a function of energy through the range 20 keV - 3 MeV, - demonstration of imaging capability in each mode, - measurement of intrinsic detector non-uniformity and understanding of the effects of passive materials surrounding the detector plane, and - discovery (and closure) of various leakage paths through the passive shielding system

  19. Ground motion effects

    Energy Technology Data Exchange (ETDEWEB)

    Blume, J A [John A. Blume and Associates, San Francisco, CA (United States)

    1969-07-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  20. The LOFT Ground Segment

    DEFF Research Database (Denmark)

    Bozzo, E.; Antonelli, A.; Argan, A.

    2014-01-01

    targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT...... Burst alert System additionally identifies on-board bright impulsive events (e.g., Gamma-ray Bursts, GRBs) and broadcasts the corresponding position and trigger time to the ground using a dedicated system of ~15 VHF receivers. All WFM data are planned to be made public immediately. In this contribution...... we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book 1 . We describe the expected GS contributions from ESA and the LOFT consortium. A review is provided of the planned LOFT data products and the details of the data flow, archiving...

  1. Ground motion effects

    International Nuclear Information System (INIS)

    Blume, J.A.

    1969-01-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  2. Unmanned Ground Systems Roadmap

    Science.gov (United States)

    2011-07-01

    quality metric tracking history . 1.4.3.4 Technical Management Division The mission of the RS JPO Technical Management (Tech Mgt) Division is to...missions dictate radio capabilities. IP version 4 ( IPv4 ) is the common IP standard used on IP addressable devices of UGVs, however, Unmanned Ground...Systems Roadmap UNCLASSIFIED 26 UNCLASSIFIED July 2011 IPv4 addresses are projected to run out and UGV systems will need to migrate to IP version 6

  3. Ground System Survivability Overview

    Science.gov (United States)

    2012-03-27

    Avoidance Blast Mitigation Optimization Customer ILIR RDT&E Funding 5.0 % 0.5% GSS has a proven, technically proficient workforce that meets...Evaluation of Defensive-Aid Suites (ARMED) Common Automatic Fire Extinguishing System ( CAFES ) Transparent Armor Development Ground Combat Vehicle...Survey TRADOC (WFO, CNA, etc) Voice of the Customer Sy st em s En gi ne er in g Publish overarching MIL-STD, design guidelines, technical

  4. Crystalline beam ground state

    International Nuclear Information System (INIS)

    Wei, Jie; Li, Xiao-Ping; Sessler, A.M.

    1993-01-01

    In order to employ Molecular Dynamics method, commonly used in condensed matter physics, we have derived the equations of motion for a beam of charged particles in the rotating rest frame of the reference particle. We include in the formalism that the particles are confined by the guiding and focusing magnetic fields, and that they are confined in a conducting vacuum pipe while interacting with each other via a Coulomb force. Numerical simulations has been performed to obtain the equilibrium structure. The effects of the shearing force, centrifugal force, and azimuthal variation of the focusing strength are investigated. It is found that a constant gradient storage ring can not give a crystalline beam, but that an alternating-gradient (AG) structure can. In such a machine the ground state is, except for one-dimensional (1-D) crystals, time-dependent. The ground state is a zero entropy state, despite the time-dependent, periodic variation of the focusing force. The nature of the ground state, similar to that found by Rahman and Schiffer, depends upon the density and the relative focusing strengths in the transverse directions. At low density, the crystal is 1-D. As the density increases, it transforms into various kinds of 2-D and 3-D crystals. If the energy of the beam is higher than the transition energy of the machine, the crystalline structure can not be formed for lack of radial focusing

  5. Crystalline beam ground state

    International Nuclear Information System (INIS)

    Wei, Jie; Li, Xiao-Ping

    1993-01-01

    In order to employ molecular dynamics (MD) methods, commonly used in condensed matter physics, we have derived the equations of motion for a beam of charged particles in the rotating rest frame of the reference particle. We include in the formalism that the particles are confined by the guiding and focusing magnetic fields, and that they are confined in a conducting vacuum pipe while interacting with each other via a Coulomb force. Numerical simulations using MD methods has been performed to obtain the equilibrium crystalline beam structure. The effect of the shearing force, centrifugal force, and azimuthal variation of the focusing strength are investigated. It is found that a constant gradient storage ring can not give a crystalline beam, but that an alternating-gradient (AG) structure can. In such a machine the ground state is, except for one-dimensional (1-D) crystals, time dependent. The ground state is a zero entropy state, despite the time-dependent, periodic variation of the focusing force. The nature of the ground state, similar to that found by Schiffer et al. depends upon the density and the relative focusing strengths in the transverse directions. At low density, the crystal is 1-D. As the density increases, it transforms into various kinds of 2-D and 3-D crystals. If the energy of the beam is higher than the transition energy of the machine, the crystalline structure can not be formed for lack of radial focusing

  6. Crystalline beam ground state

    International Nuclear Information System (INIS)

    Wei, J.; Li, X.P.

    1993-01-01

    In order to employ the Molecular Dynamics method, commonly used in condensed matter physics, the authors have derived the equations of motion for a beam of charged particles in the rotating rest frame of the reference particle. They include in the formalism that the particles are confined by the guiding and focusing magnetic fields, and that they are confined in a conducting vacuum pipe while interacting with each other via a Coulomb force. Numerical simulations has been performed to obtain the equilibrium structure. The effects of the shearing force, centrifugal force, and azimuthal variation of the focusing strength are investigated. It is found that a constant gradient storage ring can not give a crystalline beam, but that an alternating-gradient (AG) structure can. In such a machine the ground state is, except for one-dimensional (1-D) crystals, time-dependent. The ground state is a zero entropy state, despite the time-dependent, periodic variation of the focusing force. The nature of the ground state, similar to that found by Rahman and Schiffer, depends upon the density and the relative focusing strengths in the transverse directions. At low density, the crystal is 1-D. As the density increases, it transforms into various kinds of 2-D and 3-D crystals. If the energy of the beam is higher than the transition energy of the machine, the crystalline structure can not be formed for lack of radial focusing

  7. Effects of drought and prolonged winter on Townsend's ground squirrel demography in shrubsteppe habitats

    Science.gov (United States)

    Van Horne, Beatrice; Olson, Gail S.; Schooley, Robert L.; Corn, Janelle G.; Burnham, Kenneth P.

    1997-01-01

    During a mark–recapture study of Townsend's ground squirrels (Spermophilus townsendii) on 20 sites in the Snake River Birds of Prey National Conservation Area, Idaho, in 1991 through 1994, 4407 animals were marked in 17639 capture events. This study of differences in population dynamics of Townsend's ground squirrels among habitats spanned a drought near the extreme of the 130-yr record, followed by prolonged winter conditions.Townsend's ground squirrels have a short active season (≈4 mo) in which to reproduce and store fat for overwintering. Their food consists largely of succulent grasses and forbs in this dry shrubsteppe and grassland habitat. The drought in the latter half of the 1992 active season produced early drying of Sandberg's bluegrass (Poa secunda) and was associated with low adult and juvenile body masses prior to immergence into estivation/hibernation. The following prolonged winter was associated with late emergence of females in 1993. Early-season body masses of adults were low in 1993 relative to 1992, whereas percentage of body fat in males was relatively high. These weather patterns in spring 1992 and winter 1993 also resulted in reduced adult persistence through the ≈7-mo inactive period, especially for adult females, and near-zero persistence of >1200 juveniles. Consequently, densities of Townsend's ground squirrels across the 20 livetrap sites declined.The demographic effects of drought and prolonged winter lasted at least through the subsequent breeding season. Adult females that survived these weather extremes produced fewer emergent young per female than did adult females prior to the event. Prior to the drought/prolonged winter, yearling female body masses were higher than, or indistinguishable from, those of adults. Females produced in 1993 had lower body masses as yearlings than did adult females.Demographic response to the drought and prolonged winter varied with habitat; ground squirrels in sagebrush habitat showed less decline

  8. Simulated earthquake ground motions

    International Nuclear Information System (INIS)

    Vanmarcke, E.H.; Gasparini, D.A.

    1977-01-01

    The paper reviews current methods for generating synthetic earthquake ground motions. Emphasis is on the special requirements demanded of procedures to generate motions for use in nuclear power plant seismic response analysis. Specifically, very close agreement is usually sought between the response spectra of the simulated motions and prescribed, smooth design response spectra. The features and capabilities of the computer program SIMQKE, which has been widely used in power plant seismic work are described. Problems and pitfalls associated with the use of synthetic ground motions in seismic safety assessment are also pointed out. The limitations and paucity of recorded accelerograms together with the widespread use of time-history dynamic analysis for obtaining structural and secondary systems' response have motivated the development of earthquake simulation capabilities. A common model for synthesizing earthquakes is that of superposing sinusoidal components with random phase angles. The input parameters for such a model are, then, the amplitudes and phase angles of the contributing sinusoids as well as the characteristics of the variation of motion intensity with time, especially the duration of the motion. The amplitudes are determined from estimates of the Fourier spectrum or the spectral density function of the ground motion. These amplitudes may be assumed to be varying in time or constant for the duration of the earthquake. In the nuclear industry, the common procedure is to specify a set of smooth response spectra for use in aseismic design. This development and the need for time histories have generated much practical interest in synthesizing earthquakes whose response spectra 'match', or are compatible with a set of specified smooth response spectra

  9. Ground System Extensibility Considerations

    Science.gov (United States)

    Miller, S. W.; Greene, E.

    2017-12-01

    The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a multi-mission enterprise system serving NOAA, NASA and their national and international partners, such as NASA's Earth Observation System (EOS), NOAA's current POES, the Japan Aerospace Exploration Agency's (JAXA) Global Change Observation Mission - Water (GCOM-W1), and DoD's Defense Meteorological Satellite Program (DMSP). The CGS provides a wide range of support to a number of national and international missions, including command and control, mission management, data acquisition and routing, and environmental data processing and distribution. The current suite of CGS-supported missions has demonstrated the value of interagency and international partnerships to address global observation needs. With its established infrastructure and existing suite of missions, the CGS is extensible to a wider array of potential new missions. This paper will describe how the inherent scalability and extensibility of the CGS enables the addition of these new missions, with an eye on global enterprise needs in the 2020's and beyond.

  10. Ground penetrating radar

    CERN Document Server

    Daniels, David J

    2004-01-01

    Ground-penetrating radar has come to public attention in recent criminal investigations, but has actually been a developing and maturing remote sensing field for some time. In the light of recent expansion of the technique to a wide range of applications, the need for an up-to-date reference has become pressing. This fully revised and expanded edition of the best-selling Surface-Penetrating Radar (IEE, 1996) presents, for the non-specialist user or engineer, all the key elements of this technique, which span several disciplines including electromagnetics, geophysics and signal processing. The

  11. Predicting Ground Illuminance

    Science.gov (United States)

    Lesniak, Michael V.; Tregoning, Brett D.; Hitchens, Alexandra E.

    2015-01-01

    Our Sun outputs 3.85 x 1026 W of radiation, of which roughly 37% is in the visible band. It is directly responsible for nearly all natural illuminance experienced on Earth's surface, either in the form of direct/refracted sunlight or in reflected light bouncing off the surfaces and/or atmospheres of our Moon and the visible planets. Ground illuminance, defined as the amount of visible light intercepting a unit area of surface (from all incident angles), varies over 7 orders of magnitude from day to night. It is highly dependent on well-modeled factors such as the relative positions of the Sun, Earth, and Moon. It is also dependent on less predictable factors such as local atmospheric conditions and weather.Several models have been proposed to predict ground illuminance, including Brown (1952) and Shapiro (1982, 1987). The Brown model is a set of empirical data collected from observation points around the world that has been reduced to a smooth fit of illuminance against a single variable, solar altitude. It provides limited applicability to the Moon and for cloudy conditions via multiplicative reduction factors. The Shapiro model is a theoretical model that treats the atmosphere as a three layer system of light reflectance and transmittance. It has different sets of reflectance and transmittance coefficients for various cloud types.In this paper we compare the models' predictions to ground illuminance data from an observing run at the White Sands missile range (data was obtained from the United Kingdom's Meteorology Office). Continuous illuminance readings were recorded under various cloud conditions, during both daytime and nighttime hours. We find that under clear skies, the Shapiro model tends to better fit the observations during daytime hours with typical discrepancies under 10%. Under cloudy skies, both models tend to poorly predict ground illuminance. However, the Shapiro model, with typical average daytime discrepancies of 25% or less in many cases

  12. TFTR grounding scheme and ground-monitor system

    International Nuclear Information System (INIS)

    Viola, M.

    1983-01-01

    The Tokamak Fusion Test Reactor (TFTR) grounding system utilizes a single-point ground. It is located directly under the machine, at the basement floor level, and is tied to the building perimeter ground. Wired to this single-point ground, via individual 500 MCM insulated cables, are: the vacuum vessel; four toroidal field coil cases/inner support structure quadrants; umbrella structure halves; the substructure ring girder; radial beams and columns; and the diagnostic systems. Prior to the first machine operation, a ground-loop removal program was initiated. It required insulation of all hangers and supports (within a 35-foot radius of the center of the machine) of the various piping, conduits, cable trays, and ventilation systems. A special ground-monitor system was designed and installed. It actively monitors each of the individual machine grounds to insure that there are no inadvertent ground loops within the machine structure or its ground and that the machine grounds are intact prior to each pulse. The TFTR grounding system has proven to be a very manageable system and one that is easy to maintain

  13. Presurgical identification of hibernating myocardium by combined use of technetium-99m hexakis 2-methoxyisobutylisonitrile single photon emission tomography and fluorine-18 fluoro-2-deoxy-D-glucose positron emission tomography in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Lucignani, G.; Landoni, C.; Paganelli, G.; Vanoli, G.; Rossetti, C.; Gilardi, M.C.; Colombo, F.; Fazio, F.; Paolini, G.; Zuccari, M.; Di Credico, G.; Mariani, M.A.; Grossi, A.; Galli, L.

    1992-01-01

    We tested the possibility of identifying areas of hibernating myocardium by the combined assessment of perfusion and metabolism using SPET with 99m Tc-MIBI and PET with 18 F-FDG. Segmental wall motion, perfusion and 18 F-FDG uptake were scored in 5 segments in 14 patients with coronary artery disease (CAD), for a total number of 70 segments. Each subject underwent the following studies prior to and following coronary artery-bypass grafting (CABG): First-pass radionuclide angiography, electrocardiography gated planar perfusion scintigraphy and SPET perfusion scintigraphy with 99m Tc-MIBI and, after 16 fasting, 18 F-FDG PET metabolic scintigraphy. Wall motion impairment was either decreased or completely reversed by CABG in 95% of the asynergic segments which exhibited 18 F-FDG uptake, whereas it was unmodified in 80% of the asynergic segments with no 18 Fe-FDG uptake. A stepwise multiple logistic analysis was carried out on the asynergic segments to estimate the postoperative probability of wall motion improvement on the basis of the preoperative regional perfusion and metabolic scores. The segments with the highest probability of functional recovery from preoperative asynergy after revascularization were those with a marked 18 F-FDG uptake prior to CABG. High probabilities of functional recovery were also estimated for the segments presenting with moderate and low 18 F-FDG uptake. A low probability of functional recovery was estimated in the segments with no 18 F-FDG uptake. Despite the potential limitations due to the semiquantitative analysis of the images, the method appears to provide reliable information for the diagnostic and prognostic evaluation of patients with CAD undergoing CABG and confirms that the identification of hibernating myocardium with 18 F-FDG is of paramount importance in the diagnosis of patients undergoing CABG. (orig.)

  14. A thermal ground cloak

    International Nuclear Information System (INIS)

    Yang, Tianzhi; Wu, Qinghe; Xu, Weikai; Liu, Di; Huang, Lujun; Chen, Fei

    2016-01-01

    The thermal cloak has been a long-standing scientific dream of researchers and engineers. Recently thermal metamaterials with man-made micro-structure have been presented based on the principle of transformation optics (TO). This new concept has received considerable attention, which is a powerful tool for manipulating heat flux in thermal imaging systems. However, the inherent material singularity has long been a captivation of experimental realization. As an alternative method, the scattering-cancellation-based cloak (or bi-layer thermal cloak) has been presented to remove the singularity for achieving the same cloaking performance. Nevertheless, such strategy needs prerequisite knowledge (geometry and conductivity) of the object to be cloaked. In this paper, a new thermal ground cloak is presented to overcome the limitations. The device is designed, fabricated and measured to verify the thermal cloaking performance. We experimentally show that the remarkably low complexity of the device can fully and effectively be manipulated using realizable transformation thermal devices. More importantly, this thermal ground cloak is designed to exclude heat flux without knowing the information of the cloaked object. - Highlights: • We present the first thermal carpet cloak. • The carpet can thermally cloak any shaped object without knowing the properties of the object to be cloaked. • Excellent agreements between simulation and experiment are observed.

  15. Grounding for safety

    Energy Technology Data Exchange (ETDEWEB)

    Prud' homme, P. [Hydro-Quebec, Montreal, PQ (Canada). TransEnergie Div.

    2006-07-01

    The importance of providing electrical grounds as a safety issue in the design of power transmission lines was discussed. Power transmission lines extend over several thousands of kilometers crossing various environments, including communities where electric utilities encourage the use of transmission rights-of-way passages for uses such as bicycle paths. In recent years, many new residential communities have been built at the border of power transmission rights-of-ways or substations. In view of this emerging trend, and the fact that internal statistics indicate that lightning strikes are responsible of about 50 to 60 per cent of transmission line faults, electric utilities are obligated to verify if their installations are safe. Hydro-Quebec TransEnergie's view on this subject was presented along with a review of international standards to determine if limits for touch voltage, step voltage and transferred potential close to transmission lines have been established by the international community. A variety of mitigation measures to control the increase in ground potential in the event of electrical faults were also proposed. tabs., figs.

  16. Ground Vehicle Convoying

    Science.gov (United States)

    Gage, Douglas W.; Pletta, J. Bryan

    1987-01-01

    Initial investigations into two different approaches for applying autonomous ground vehicle technology to the vehicle convoying application are described. A minimal capability system that would maintain desired speed and vehicle spacing while a human driver provided steering control could improve convoy performance and provide positive control at night and in inclement weather, but would not reduce driver manpower requirements. Such a system could be implemented in a modular and relatively low cost manner. A more capable system would eliminate the human driver in following vehicles and reduce manpower requirements for the transportation of supplies. This technology could also be used to aid in the deployment of teleoperated vehicles in a battlefield environment. The needs, requirements, and several proposed solutions for such an Attachable Robotic Convoy Capability (ARCC) system will be discussed. Included are discussions of sensors, communications, computers, control systems and safety issues. This advanced robotic convoy system will provide a much greater capability, but will be more difficult and expensive to implement.

  17. Common Ground and Delegation

    DEFF Research Database (Denmark)

    Dobrajska, Magdalena; Foss, Nicolai Juul; Lyngsie, Jacob

    preconditions of increasing delegation. We argue that key HR practices?namely, hiring, training and job-rotation?are associated with delegation of decision-making authority. These practices assist in the creation of shared knowledge conditions between managers and employees. In turn, such a ?common ground......? influences the confidence with which managers delegate decision authority to employees, as managers improve their knowledge of the educational background, firm-specific knowledge, and perhaps even the possible actions of those to whom they delegate such authority. To test these ideas, we match a large......-scale questionnaire survey with unique population-wide employer-employee data. We find evidence of a direct and positive influence of hiring decisions (proxied by common educational background), and the training and job rotation of employees on delegation. Moreover, we find a positive interaction between common...

  18. GROUNDED THEORY METHODOLOGY and GROUNDED THEORY RESEARCH in TURKEY

    OpenAIRE

    ARIK, Ferhat; ARIK, Işıl Avşar

    2016-01-01

    This research discusses the historical development of the Grounded Theory Methodology, which is one of the qualitative research method, its transformation over time and how it is used as a methodology in Turkey. The Grounded Theory which was founded by Strauss and Glaser, is a qualitative methodology based on inductive logic to discover theories in contrast with the deductive understanding which is based on testing an existing theory in sociology. It is possible to examine the Grounded Theory...

  19. Ground-water travel time

    International Nuclear Information System (INIS)

    Bentley, H.; Grisak, G.

    1985-01-01

    The Containment and Isolation Working Group considered issues related to the postclosure behavior of repositories in crystalline rock. This working group was further divided into subgroups to consider the progress since the 1978 GAIN Symposium and identify research needs in the individual areas of regional ground-water flow, ground-water travel time, fractional release, and cumulative release. The analysis and findings of the Ground-Water Travel Time Subgroup are presented

  20. Regional ground-water system

    International Nuclear Information System (INIS)

    Long, J.

    1985-01-01

    The Containment and Isolation Working Group considered issues related to the postclosure behavior of repositories in crystalline rock. This working group was further divided into subgroups to consider the progress since the 1978 GAIN Symposium and identify research needs in the individual areas of regional ground-water flow, ground-water travel time, fractional release, and cumulative release. The analysis and findings of the Ground-Water Regime Subgroup are presented

  1. Phenological changes of the most commonly sampled ground beetle (Coleoptera: Carabidae) species in the UK environmental change network

    Science.gov (United States)

    Pozsgai, Gabor; Baird, John; Littlewood, Nick A.; Pakeman, Robin J.; Young, Mark R.

    2018-03-01

    Despite the important roles ground beetles (Coleoptera: Carabidae) play in ecosystems, the highly valued ecosystem services they provide, and ample descriptive documentation of their phenology, the relative impact of various environmental factors on carabid phenology is not well studied. Using the long-term pitfall trap capture data from 12 terrestrial Environmental Change Network (ECN) sites from the UK, we examined how changing climate influenced the phenology of common carabids, and the role particular climate components had on phenological parameters. Of the 28 species included in the analyses, 19 showed earlier start of their activity. This advance was particularly pronounced in the spring, supporting the view that early phenophases have a greater tendency to change and these changes are more directly controlled by temperature than later ones. Autumn activity extended only a few cases, suggesting a photoperiod-driven start of hibernation. No association was found between life-history traits and the ability of species to change their phenology. Air temperatures between April and June were the most important factors determining the start of activity of each species, whilst late season precipitation hastened the cessation of activity. The balance between the advantages and disadvantages of changing phenology on various levels is likely to depend on the species and even on local environmental criteria. The substantially changing phenology of Carabidae may influence their function in ecosystems and the ecosystem services they provide.

  2. [Seasonal changes in tumor necrosis factor production in hibernating animals in normal conditions and under the effects of electromagnetic and ionizing radiation].

    Science.gov (United States)

    Ogaĭ, V B; Novoselova, E G; Makar, V R; Kolaeva, S G

    2002-01-01

    Production of tumor necrosis factor (TNF) has been investigated in peritoneal macrophages and splenic T cells of Arctic Yakutian ground squirrel (Citellus Undulatus Pallas) upon in vitro action of electromagnetic and ionizing radiation during annual cycle. The significant activation of TNF production in the cells of awaken ground squirrels in winter and increasing level of the lymphokine production at spring-summer period has been indicated. The level of TNF production in splenic T cells was not changed during whole year. The electromagnetic radiation (EMR) of low intensity (8.15-18 GHz, 1 microW/cm2) induced an augmentation of both secretory and proliferative activity in TNF-producing cells. Ionizing radiation suppressed T cell proliferation, but the doses 2 and 5 Gy resulted in a significant stimulation of TNF production in T cells and macrophages.

  3. Ground Attenuation of Railroad Noise

    DEFF Research Database (Denmark)

    Makarewicz, R.; Rasmussen, Karsten Bo; Kokowski, P.

    1996-01-01

    The influence of ground effect on railroad noise is described using the concept of the peak A-weighted sound exposure level, and A-weighted sound exposure level. The train is modelled by a continuous line of incoherent point sources that have a cosine directivity. The ground effect is included...

  4. Grounding Damage to Conventional Vessels

    DEFF Research Database (Denmark)

    Lützen, Marie; Simonsen, Bo Cerup

    2003-01-01

    The present paper is concerned with rational design of conventional vessels with regard to bottom damage generated in grounding accidents. The aim of the work described here is to improve the design basis, primarily through analysis of new statistical data for grounding damage. The current regula...

  5. Ground-based photo monitoring

    Science.gov (United States)

    Frederick C. Hall

    2000-01-01

    Ground-based photo monitoring is repeat photography using ground-based cameras to document change in vegetation or soil. Assume those installing the photo location will not be the ones re-photographing it. This requires a protocol that includes: (1) a map to locate the monitoring area, (2) another map diagramming the photographic layout, (3) type and make of film such...

  6. Electrochemical stabilization of clayey ground

    Science.gov (United States)

    Rzhanitzin, B.A.; Sokoloff, V.P.

    1947-01-01

    Recently developed new methods of stabilization of weak grounds (e.g. the silicate treatment) are based on injection of chemical solutions into the ground. Such methods are applicable accordingly only to the kinds of ground that have the coefficient of filtration higher than 2 meters per 24 hours and permit penetration of the chemical solutions under pressure. This limit, however, as it is shown by our experience in construction, excludes a numerous and an important class of grounds, stabilization of which is indispensable in many instances. For example, digging of trenches and pits in clayey, silty, or sandy ground shows that all these types act like typical "floaters" (sluds? -S) in the presence of the ground water pressure. There were several instances in the canalization of the city of Moskow where the laying of trenches below the ground water level has led to extreme difficulties with clayey and silty ground. Similar examples could be cited in mining, engineering hydrology, and railroad construction. For these reasons, the development of methods of stabilizing such difficult types of ground has become an urgent problem of our day. In 1936, the author began his investigations, at the ground Stabilization Laboratory of VODGEO Institute, with direct electrical current as the means of stabilization of grounds. Experiments had shown that a large number of clayey types, following passage of direct electrical current, undergoes a transformation of its physico-chemical properties. It was established that the (apparent -S) density of the ground is substantially increased in consequence of the application of direct electrical current. The ground loses also its capacity to swell and to soften in water. Later, after a more detailed study of the physico-chemical mechanism of the electrical stabilization, it became possible to develop the method so as to make it applicable to sandy and silty as well as to clayey ground. By this time (1941, S.), the method has already been

  7. On LHCb muon MWPC grounding

    CERN Document Server

    Kashchuk, A

    2006-01-01

    My goal is to study how a big MWPC system, in particular the LHCb muon system, can be protected against unstable operation and multiple spurious hits, produced by incorrect or imperfect grounding in the severe EM environment of the LHCb experiment. A mechanism of penetration of parasitic current from the ground loop to the input of the front-end amplifier is discussed. A new model of the detector cell as the electrical bridge is considered. As shown, unbalance of the bridge makes detector to be sensitive to the noise in ground loop. Resonances in ground loop are specified. Tests of multiple-point and single-point grounding conceptions made on mock-up are presented.

  8. On Grounding of Fast Ships

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Pedersen, Preben Terndrup

    1997-01-01

    The paper deals with analysis of grounding of high-speed crafts. It is the purpose to present a comprehensive mathematical model for calculation of the overall dynamic ship response during grounding. This procedure is applied to derive the motions, the time varying sectional forces and the local...... loads during grounding on plane, sloping, sandy bottoms for six different designs of fast monohull ships made from steel, aluminium or GRP sandwich materials. The results show that the effect of the hull flexibility is to reduce the overall dynamic sectional loads on the hull girder. The considered...... numerical examples also indicate that, even with impact speeds of 40 knots against a 1:10 sloping bottom, the global strength of the hull girder is not exceeded by the grounding induced loads.For the local deformation of high-speed ship hulls at the point of contact with the ground, the paper presents...

  9. Regional analysis of ground and above-ground climate

    Science.gov (United States)

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of Earth tempering as a practice and of specific Earth sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground are included. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 20 locations in the United States.

  10. Regional analysis of ground and above-ground climate

    Energy Technology Data Exchange (ETDEWEB)

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long-term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of earth tempering as a practice and of specific earth-sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Also contained in the report are reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 29 locations in the United States.

  11. Ground Control System Description Document

    International Nuclear Information System (INIS)

    Eric Loros

    2001-01-01

    The Ground Control System contributes to the safe construction and operation of the subsurface facility, including accesses and waste emplacement drifts, by maintaining the configuration and stability of the openings during construction, development, emplacement, and caretaker modes for the duration of preclosure repository life. The Ground Control System consists of ground support structures installed within the subsurface excavated openings, any reinforcement made to the rock surrounding the opening, and inverts if designed as an integral part of the system. The Ground Control System maintains stability for the range of geologic conditions expected at the repository and for all expected loading conditions, including in situ rock, construction, operation, thermal, and seismic loads. The system maintains the size and geometry of operating envelopes for all openings, including alcoves, accesses, and emplacement drifts. The system provides for the installation and operation of sensors and equipment for any required inspection and monitoring. In addition, the Ground Control System provides protection against rockfall for all subsurface personnel, equipment, and the engineered barrier system, including the waste package during the preclosure period. The Ground Control System uses materials that are sufficiently maintainable and that retain the necessary engineering properties for the anticipated conditions of the preclosure service life. These materials are also compatible with postclosure waste isolation performance requirements of the repository. The Ground Control System interfaces with the Subsurface Facility System for operating envelopes, drift orientation, and excavated opening dimensions, Emplacement Drift System for material compatibility, Monitored Geologic Repository Operations Monitoring and Control System for ground control instrument readings, Waste Emplacement/Retrieval System to support waste emplacement operations, and the Subsurface Excavation System

  12. Alternatives for ground water cleanup

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Geosciences, Environment and Resources; Division on Earth and Life Studies; National Research Council; National Academy of Sciences

    .... Yet recent studies question whether existing technologies can restore contaminated ground water to drinking water standards, which is the goal for most sites and the result expected by the public...

  13. Integrated Ground Operations Demonstration Units

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the AES Integrated Ground Operations Demonstration Units (IGODU) project is to demonstrate cost efficient cryogenic operations on a relevant...

  14. Imaging of Moving Ground Vehicles

    National Research Council Canada - National Science Library

    Rihaczek, A

    1996-01-01

    ... requires that use be made of the complex image. The yaw/pitch/roll/bounce/flex motion of a moving ground vehicle demands that different motion compensations be applied to different parts of the vehicle...

  15. Humic substances in ground waters

    International Nuclear Information System (INIS)

    Paxeus, N.; Allard, B.; Olofsson, U.; Bengtsson, M.

    1986-01-01

    The presence of naturally occurring complexing agents that may enhance the migration of disposed radionuclikes and thus facilitate their uptake by plantsis a problem associated with the underground disposal of radioactive wastes in bedrock. The main purpose of this work is to characterized humic substances from ground water and compare them with humic substances from surface water. The humic materials isolated from ground waters of a borehole in Fjaellveden (Sweden) were characterized by elemental and functional group analyses. Spectroscopic properties, molecular weight distributions as well as acid-base properties of the fulvic and humic fractions were also studied. The ground water humic substances were found to be quite similar in many respects (but not identical) to the Swedish surface water humics concentrated from the Goeta River but appeared to be quite different from the American ground water humics from Biscayne Florida Aquifer or Laramie Fox-Hills in Colorado. The physico-chemical properties of the isolated humic materials are discussed

  16. Ground Water and Climate Change

    Science.gov (United States)

    Taylor, Richard G.; Scanlon, Bridget; Doell, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; hide

    2013-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  17. Ground Beef and Food Safety

    Science.gov (United States)

    ... 4 days. If frozen, it should keep its quality for about 4 months. When reheating fully cooked patties or casseroles containing ground beef, be sure the internal temperature reaches 165 °F (73.9 °C). Why ...

  18. Evaluation of multimodal ground cues

    DEFF Research Database (Denmark)

    Nordahl, Rolf; Lecuyer, Anatole; Serafin, Stefania

    2012-01-01

    This chapter presents an array of results on the perception of ground surfaces via multiple sensory modalities,with special attention to non visual perceptual cues, notably those arising from audition and haptics, as well as interactions between them. It also reviews approaches to combining...... synthetic multimodal cues, from vision, haptics, and audition, in order to realize virtual experiences of walking on simulated ground surfaces or other features....

  19. Modeled ground water age distributions

    Science.gov (United States)

    Woolfenden, Linda R.; Ginn, Timothy R.

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  20. Typhoon-Induced Ground Deformation

    Science.gov (United States)

    Mouyen, M.; Canitano, A.; Chao, B. F.; Hsu, Y.-J.; Steer, P.; Longuevergne, L.; Boy, J.-P.

    2017-11-01

    Geodetic instruments now offer compelling sensitivity, allowing to investigate how solid Earth and surface processes interact. By combining surface air pressure data, nontidal sea level variations model, and rainfall data, we systematically analyze the volumetric deformation of the shallow crust at seven borehole strainmeters in Taiwan induced by 31 tropical cyclones (typhoons) that made landfall to the island from 2004 to 2013. The typhoon's signature consists in a ground dilatation due to air pressure drop, generally followed by a larger ground compression. We show that this compression phase can be mostly explained by the mass loading of rainwater that falls on the ground and concentrates in the valleys towards the strainmeter sensitivity zone. Further, our analysis shows that borehole strainmeters can help quantifying the amount of rainwater accumulating and flowing over a watershed during heavy rainfalls, which is a useful constraint for building hydrological models.

  1. Free Swimming in Ground Effect

    Science.gov (United States)

    Cochran-Carney, Jackson; Wagenhoffer, Nathan; Zeyghami, Samane; Moored, Keith

    2017-11-01

    A free-swimming potential flow analysis of unsteady ground effect is conducted for two-dimensional airfoils via a method of images. The foils undergo a pure pitching motion about their leading edge, and the positions of the body in the streamwise and cross-stream directions are determined by the equations of motion of the body. It is shown that the unconstrained swimmer is attracted to a time-averaged position that is mediated by the flow interaction with the ground. The robustness of this fluid-mediated equilibrium position is probed by varying the non-dimensional mass, initial conditions and kinematic parameters of motion. Comparisons to the foil's fixed-motion counterpart are also made to pinpoint the effect that free swimming near the ground has on wake structures and the fluid-mediated forces over time. Optimal swimming regimes for near-boundary swimming are determined by examining asymmetric motions.

  2. Compensation for incoherent ground motion

    International Nuclear Information System (INIS)

    Shigeru, Takeda; Hiroshi, Matsumoto; Masakazu, Yoshioka; Yasunori, Takeuchi; Kikuo, Kudo; Tsuneya, Tsubokawa; Mitsuaki, Nozaki; Kiyotomo, Kawagoe

    1999-01-01

    The power spectrum density and coherence function for ground motions are studied for the construction of the next generation electron-positron linear collider. It should provide a center of mass energy between 500 GeV-1 TeV with luminosity as high as 10 33 to 10 34 cm -2 sec -1 . Since the linear collider has a relatively slow repetition rate, large number of particles and small sizes of the beam should be generated and preserved in the machine to obtain the required high luminosity. One of the most critical parameters is the extremely small vertical beam size at the interaction point, thus a proper alignment system for the focusing and accelerating elements of the machine is necessary to achieve the luminosity. We describe recent observed incoherent ground motions and an alignment system to compensate the distortion by the ground motions. (authors)

  3. The automated ground network system

    Science.gov (United States)

    Smith, Miles T.; Militch, Peter N.

    1993-01-01

    The primary goal of the Automated Ground Network System (AGNS) project is to reduce Ground Network (GN) station life-cycle costs. To accomplish this goal, the AGNS project will employ an object-oriented approach to develop a new infrastructure that will permit continuous application of new technologies and methodologies to the Ground Network's class of problems. The AGNS project is a Total Quality (TQ) project. Through use of an open collaborative development environment, developers and users will have equal input into the end-to-end design and development process. This will permit direct user input and feedback and will enable rapid prototyping for requirements clarification. This paper describes the AGNS objectives, operations concept, and proposed design.

  4. 46 CFR 183.376 - Grounded distribution systems (neutral grounded).

    Science.gov (United States)

    2010-10-01

    ....376 Section 183.376 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER... propulsion, power, lighting, or distribution system having a neutral bus or conductor must have the neutral... generator to ground before the generator is connected to the bus, except the neutral of an emergency power...

  5. 46 CFR 120.376 - Grounded distribution systems (Neutral grounded).

    Science.gov (United States)

    2010-10-01

    ....376 Section 120.376 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE THAN 150 PASSENGERS OR WITH OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS... distribution system having a neutral bus or conductor must have the neutral grounded. (c) The neutral or each...

  6. Ground-truth measurement systems

    Science.gov (United States)

    Serafin, R.; Seliga, T. A.; Lhermitte, R. M.; Nystuen, J. A.; Cherry, S.; Bringi, V. N.; Blackmer, R.; Heymsfield, G. M.

    1981-01-01

    Ground-truth measurements of precipitation and related weather events are an essential component of any satellite system designed for monitoring rainfall from space. Such measurements are required for testing, evaluation, and operations; they provide detailed information on the actual weather events, which can then be compared with satellite observations intended to provide both quantitative and qualitative information about them. Also, very comprehensive ground-truth observations should lead to a better understanding of precipitation fields and their relationships to satellite data. This process serves two very important functions: (a) aiding in the development and interpretation of schemes of analyzing satellite data, and (b) providing a continuing method for verifying satellite measurements.

  7. The Mirror in the Ground

    DEFF Research Database (Denmark)

    Shepherd, Nick

    An important and original contribution to the study of the archive, The Mirror in the Ground approaches the discipline of archaeology in South Africa from the perspective of an interest in visualities. Author Nick Shepherd argues that it makes sense to talk about an archaeological aesthetics...... at the University of Cape Town, where he convenes a graduate programme on Public Culture and Heritage. The Mirror in the Ground is the first volume in the relaunched Series in Visual Histories, produced by the Centre for Curating the Archive (CCA) at the University of Cape Town....

  8. 14 CFR 417.109 - Ground safety.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Ground safety. 417.109 Section 417.109... TRANSPORTATION LICENSING LAUNCH SAFETY Launch Safety Responsibilities § 417.109 Ground safety. (a) Ground safety... 417.115(c), and subpart E of this part provide launch operator ground safety requirements. ...

  9. Ship Collision and Grounding Analysis

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    2010-01-01

    It is the purpose of the paper to present a review of prediction and analysis tools for collision and grounding analyses and to outline a probabilistic procedure whereby these tools can be used by the maritime industry to develop performance based rules to reduce the risk associated with human, e...

  10. The Steksovo II burial ground

    Directory of Open Access Journals (Sweden)

    Martianov Vladimir N.

    2014-12-01

    Full Text Available The article is dedicated to the results of many-years’ (1990-2010 excavations on the ancient Mordovian Steksovo II burial ground site. The burial ground had functioned in the 3rd to 13th centuries AD. The investigations revealed hundreds of burials, which enabled the researchers to judge upon the wealth of material items found and the variety of burial rites of the population that had formed the burial ground. The 1st millennium AD is characterized by bi-ritualism, while inhumation is characteristic of the 11-13th-century period; horses’ burials were also discovered. The data of the burial ground make it possible to modify the concept of the stages in ancient Mordovians ethnogenesis. It is generally attributed to the Erzya Mordvins, but in early burials the combination of the Erzya and Moksha ancientries is traced. Complexes of the items of crucial importance for the chronology of the burial are discussed in the article with a representation of statistical data characterizing funeral rites and traditions.

  11. The ground stones from Sphinx

    Czech Academy of Sciences Publication Activity Database

    Řídký, Jaroslav

    2017-01-01

    Roč. 2017, č. 21 (2017), s. 39-42 ISSN 1369-5770 Grant - others:GA ČR(CZ) GA17-03207S Institutional support: RVO:67985912 Keywords : Sudan * Mesolithic * ground stones Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology

  12. Grounded theory in music therapy research.

    Science.gov (United States)

    O'Callaghan, Clare

    2012-01-01

    Grounded theory is one of the most common methodologies used in constructivist (qualitative) music therapy research. Researchers use the term "grounded theory" when denoting varying research designs and theoretical outcomes. This may be challenging for novice researchers when considering whether grounded theory is appropriate for their research phenomena. This paper examines grounded theory within music therapy research. Grounded theory is briefly described, including some of its "contested" ideas. A literature search was conducted using the descriptor "music therapy and grounded theory" in Pubmed, CINAHL PsychlNFO, SCOPUS, ERIC (CSA), Web of Science databases, and a music therapy monograph series. A descriptive analysis was performed on the uncovered studies to examine researched phenomena, grounded theory methods used, and how findings were presented, Thirty music therapy research projects were found in refereed journals and monographs from 1993 to "in press." The Strauss and Corbin approach to grounded theory dominates the field. Descriptors to signify grounded theory components in the studies greatly varied. Researchers have used partial or complete grounded theory methods to examine clients', family members', staff, music therapy "overhearers," music therapists', and students' experiences, as well as music therapy creative products and professional views, issues, and literature. Seven grounded theories were offered. It is suggested that grounded theory researchers clarify what and who inspired their design, why partial grounded theory methods were used (when relevant), and their ontology. By elucidating assumptions underpinning the data collection, analysis, and findings' contribution, researchers will continue to improve music therapy research using grounded theory methods.

  13. Adaptive ground implemented phase array

    Science.gov (United States)

    Spearing, R. E.

    1973-01-01

    The simulation of an adaptive ground implemented phased array of five antenna elements is reported for a very high frequency system design that is tolerant to the radio frequency interference environment encountered by a tracking data relay satellite. Signals originating from satellites are received by the VHF ring array and both horizontal and vertical polarizations from each of the five elements are multiplexed and transmitted down to ground station. A panel on the transmitting end of the simulation chamber contains up to 10 S-band RFI sources along with the desired signal to simulate the dynamic relationship between user and TDRS. The 10 input channels are summed, and desired and interference signals are separated and corrected until the resultant sum signal-to-interference ratio is maximized. Testing performed with this simulation equipment demonstrates good correlation between predicted and actual results.

  14. "Naturalist Inquiry" and Grounded Theory

    Directory of Open Access Journals (Sweden)

    Barney G. Glaser

    2004-01-01

    Full Text Available The world of Qualitative Data Analysis (QDA methodology became quite taken with LINCOLN and GUBA's book "Naturalist Inquiry" (1985. I have no issue with it with respect to its application to QDA; it helped clarify and advance so many QDA issues. However, its application to Grounded Theory (GT has been a major block on GT, as originated, by its cooptation and corruption hence remodeling of GT by default. LINCOLN and GUBA have simply assumed GT is just another QDA method, which it is not. In "The Grounded Theory Perspective II" (GLASER 2002a, Chapter 9 on credibility, I have discussed "Naturalist In­quiry" (NI thought regarding how LINCOLN and GUBA's notion of "trustworthy" data (or worrisome data orientation and how their view of constant comparison can and has remodeled and eroded GT. In this paper I will consider other aspects of NI that remodel GT. URN: urn:nbn:de:0114-fqs040170

  15. Block ground interaction of rockfalls

    Science.gov (United States)

    Volkwein, Axel; Gerber, Werner; Kummer, Peter

    2016-04-01

    During a rockfall the interaction of the falling block with the ground is one of the most important factors that define the evolution of a rockfall trajectory. It steers the rebound, the rotational movement, possibly brake effects, friction losses and damping effects. Therefore, if most reliable rockfall /trajectory simulation software is sought a good understanding of the block ground interaction is necessary. Today's rockfall codes enable the simulation of a fully 3D modelled block within a full 3D surface . However, the details during the contact, i.e. the contact duration, the penetration depth or the dimension of the marks in the ground are usually not part of the simulation. Recent field tests with rocks between 20 and 80 kg have been conducted on a grassy slope in 2014 [1]. A special rockfall sensor [2] within the blocks measured the rotational velocity and the acting accelerations during the tests. External video records and a so-called LocalPositioningSystem deliver information on the travel velocity. With these data not only the flight phases of the trajectories but also the contacts with the ground can be analysed. During the single jumps of a block the flight time, jump length, the velocity, and the rotation are known. During the single impacts their duration and the acting accelerations are visible. Further, the changes of rotational and translational velocity influence the next jump of the block. The change of the rotational velocity over the whole trajectory nicely visualizes the different phases of a rockfall regarding general acceleration and deceleration in respect to the inclination and the topography of the field. References: [1] Volkwein A, Krummenacher B, Gerber W, Lardon J, Gees F, Brügger L, Ott T (2015) Repeated controlled rockfall trajectory testing. [Abstract] Geophys. Res. Abstr. 17: EGU2015-9779. [2] Volkwein A, Klette J (2014) Semi-Automatic Determination of Rockfall Trajectories. Sensors 14: 18187-18210.

  16. Ground Optical Lightning Detector (GOLD)

    Science.gov (United States)

    Jackson, John, Jr.; Simmons, David

    A photometer developed to characterize lightning from the ground is discussed. The detector and the electronic signal processing and data storage systems are presented along with field data measured by the system. The discussion will include improvements that will be incorporated to enhance the measurement of lightning and the data storage capability to record for many days without human involvement. Finally, the calibration of the GOLD system is presented.

  17. Radon determination in ground water

    Energy Technology Data Exchange (ETDEWEB)

    Segovia A, N.; Bulbulian G, S

    1991-08-15

    Studies on natural radioactivity in ground water were started in Mexico in San Luis Potosi state followed by samplings from deep wells and springs in the states of Mexico and Michoacan. The samples were analyzed for solubilized and {sup 226} Ra- supported {sup 222} Rn. Some of them were also studied for {sup 234} U/ {sup 238} U activity ratio. In this paper we discuss the activities obtained and their relationship with the geologic characteristics of the studied zones. (Author)

  18. Radon determination in ground water

    International Nuclear Information System (INIS)

    Segovia A, N.; Bulbulian G, S.

    1991-08-01

    Studies on natural radioactivity in ground water were started in Mexico in San Luis Potosi state followed by samplings from deep wells and springs in the states of Mexico and Michoacan. The samples were analyzed for solubilized and 226 Ra- supported 222 Rn. Some of them were also studied for 234 U/ 238 U activity ratio. In this paper we discuss the activities obtained and their relationship with the geologic characteristics of the studied zones. (Author)

  19. Electrical Ground System Design of PEFP

    International Nuclear Information System (INIS)

    Mun, Kyeong Jun; Jeon, Gye Po; Park, Sung Sik; Min, Yi Sub; Nam, Jung Min; Cho, Jang Hyung; Kim, Jun Yeon

    2010-01-01

    Since host site host site was selected Gyeong-ju city in January, 2006. we need design revision of Proton Accelerator research center to reflect on host site characteristics and several conditions. In this paper, electrical grounding and lightning protection design scheme is introduced. In electrical grounding system design of PEFP, we classified electrical facilities into 4 groups; equipment grounding (type A), instrument grounding (Type A), high frequency instrument grounding (Type C) and lightning arrestor grounding (Type D). Lightning protection system is designed in all buildings of proton accelerator research center of PEFP, including switchyard

  20. Electrical Ground System Design of PEFP

    Energy Technology Data Exchange (ETDEWEB)

    Mun, Kyeong Jun; Jeon, Gye Po; Park, Sung Sik; Min, Yi Sub; Nam, Jung Min; Cho, Jang Hyung; Kim, Jun Yeon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    Since host site host site was selected Gyeong-ju city in January, 2006. we need design revision of Proton Accelerator research center to reflect on host site characteristics and several conditions. In this paper, electrical grounding and lightning protection design scheme is introduced. In electrical grounding system design of PEFP, we classified electrical facilities into 4 groups; equipment grounding (type A), instrument grounding (Type A), high frequency instrument grounding (Type C) and lightning arrestor grounding (Type D). Lightning protection system is designed in all buildings of proton accelerator research center of PEFP, including switchyard

  1. 33 CFR 183.415 - Grounding.

    Science.gov (United States)

    2010-07-01

    ... SAFETY BOATS AND ASSOCIATED EQUIPMENT Electrical Systems Manufacturer Requirements § 183.415 Grounding. If a boat has more than one gasoline engine, grounded cranking motor circuits must be connected to...

  2. Ground states of quantum spin systems

    International Nuclear Information System (INIS)

    Bratteli, Ola; Kishimoto, Akitaka; Robinson, D.W.

    1978-07-01

    The authors prove that ground states of quantum spin systems are characterized by a principle of minimum local energy and that translationally invariant ground states are characterized by the principle of minimum energy per unit volume

  3. Ground effect aerodynamics of racing cars

    OpenAIRE

    Zhang, Xin; Toet, Willem; Zerihan, Jonathan

    2006-01-01

    We review the progress made during the last thirty years on ground effect aerodynamics associated with race cars, in particular open wheel race cars. Ground effect aerodynamics of race cars is concerned with generating downforce, principally via low pressure on the surfaces nearest to the ground. The “ground effected” parts of an open wheeled car's aerodynamics are the most aerodynamically efficient and contribute less drag than that associated with, for example, an upper rear wing. Whilst dr...

  4. The Development of Constructivist Grounded Theory

    OpenAIRE

    Jane Mills; Ann Bonner; Karen Francis

    2006-01-01

    Constructivist grounded theory is a popular method for research studies primarily in the disciplines of psychology, education, and nursing. In this article, the authors aim to locate the roots of constructivist grounded theory and then trace its development. They examine key grounded theory texts to discern their ontological and epistemological orientation. They find Strauss and Corbin's texts on grounded theory to possess a discernable thread of constructivism in their approach to inquiry. T...

  5. Identification of resonant earthquake ground motion

    Indian Academy of Sciences (India)

    Resonant ground motion has been observed in earthquake records measured at several parts of the world. This class of ground motion is characterized by its energy being contained in a narrow frequency band. This paper develops measures to quantify the frequency content of the ground motion using the entropy ...

  6. 7 CFR 65.170 - Ground lamb.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Ground lamb. 65.170 Section 65.170 Agriculture... OF BEEF, PORK, LAMB, CHICKEN, GOAT MEAT, PERISHABLE AGRICULTURAL COMMODITIES, MACADAMIA NUTS, PECANS, PEANUTS, AND GINSENG General Provisions Definitions § 65.170 Ground lamb. Ground lamb means comminuted...

  7. 7 CFR 65.160 - Ground chicken.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Ground chicken. 65.160 Section 65.160 Agriculture... OF BEEF, PORK, LAMB, CHICKEN, GOAT MEAT, PERISHABLE AGRICULTURAL COMMODITIES, MACADAMIA NUTS, PECANS, PEANUTS, AND GINSENG General Provisions Definitions § 65.160 Ground chicken. Ground chicken means...

  8. Ground water pollution through air pollutants

    International Nuclear Information System (INIS)

    Cichorowski, G.; Michel, B.; Versteegen, D.; Wettmann, R.

    1989-01-01

    The aim of the investigation is to determine the significance of air pollutants for ground water quality and ground water use. The report summarizes present knowledge and assesses statements with a view to potential ground water pollution from the air. In this context pollution paths, the spreading behaviour of pollutants, and 'cross points' with burden potentials from other pollutant sources are presented. (orig.) [de

  9. 7 CFR 65.165 - Ground goat.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Ground goat. 65.165 Section 65.165 Agriculture... OF BEEF, PORK, LAMB, CHICKEN, GOAT MEAT, PERISHABLE AGRICULTURAL COMMODITIES, MACADAMIA NUTS, PECANS, PEANUTS, AND GINSENG General Provisions Definitions § 65.165 Ground goat. Ground goat means comminuted...

  10. 30 CFR 77.801 - Grounding resistors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding resistors. 77.801 Section 77.801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH...-Voltage Distribution § 77.801 Grounding resistors. The grounding resistor, where required, shall be of the...

  11. Stop. Write! Writing Grounded Theory

    Directory of Open Access Journals (Sweden)

    Barney G. Glaser, PhD, Hon. PhD

    2012-06-01

    Full Text Available The message in this book, the dictum in this book, is to stop and write when the Grounded Theory (GT methodology puts you in that ready position. Stop unending conceptualization, unending data coverage, and unending listening to others who would egg you on with additional data, ideas and/or requirements or simply wait too long. I will discuss these ideas in detail. My experience with PhD candidates is that for the few who write when ready, many do not and SHOULD. Simply put, many write-up, but many more should.

  12. Leaders break ground for INFINITY

    Science.gov (United States)

    2008-01-01

    Community leaders from Mississippi and Louisiana break ground for the new INFINITY at NASA Stennis Space Center facility during a Nov. 20 ceremony. Groundbreaking participants included (l to r): Gottfried Construction representative John Smith, Mississippi Highway Commissioner Wayne Brown, INFINITY board member and Apollo 13 astronaut Fred Haise, Stennis Director Gene Goldman, Studio South representative David Hardy, Leo Seal Jr. family representative Virginia Wagner, Hancock Bank President George Schloegel, Mississippi Rep. J.P. Compretta, Mississippi Band of Choctaw Indians representative Charlie Benn and Louisiana Sen. A.G. Crowe.

  13. Ground level cosmic ray observations

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, S.A. [Tata Institute of Fundamental Research, Bombay (International Commission on Radiation Units and Measurements); Grimani, C.; Brunetti, M.T.; Codino, A. [Perugia Univ. (Italy)]|[INFN, Perugia (Italy); Papini, P.; Massimo Brancaccio, F.; Piccardi, S. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Basini, G.; Bongiorno, F. [INFN, Laboratori Nazionali di Frascati, Rome (Italy); Golden, R.L. [New Mexico State Univ., Las Cruces, NM (United States). Particle Astrophysics Lab.; Hof, M. [Siegen Univ. (Germany). Fachbereich Physik

    1995-09-01

    Cosmic rays at ground level have been collected using the NMSU/Wizard - MASS2 instrument. The 17-hr observation run was made on September 9. 1991 in Fort Sumner, New Mexico, Usa. Fort Sumner is located at 1270 meters a.s.l., corresponding to an atmospheric depth of about 887 g/cm{sup 2}. The geomagnetic cutoff is 4.5 GV/c. The charge ratio of positive and negative muons and the proton to muon ratio have been determined. These observations will also be compared with data collected at a higher latitude using the same basic apparatus.

  14. Estimation of strong ground motion

    International Nuclear Information System (INIS)

    Watabe, Makoto

    1993-01-01

    Fault model has been developed to estimate a strong ground motion in consideration of characteristics of seismic source and propagation path of seismic waves. There are two different approaches in the model. The first one is a theoretical approach, while the second approach is a semi-empirical approach. Though the latter is more practical than the former to be applied to the estimation of input motions, it needs at least the small-event records, the value of the seismic moment of the small event and the fault model of the large event

  15. Global trends on local grounds

    DEFF Research Database (Denmark)

    Steensen, Jette Johanne

    2006-01-01

    Collection of papers produced by tutors involved in a master´s degree course for teacher in Ethiopia offers an important challenge to the dominant neo-liberal agenda that has taken over educational reform throughtout the world. The project was based on the practice of critical practitioner inquiry...... and built upon similar efforts in Namibia in the 1990s. Steensen´s contribution stresses that any educational system will have to lie firmly on local grounds, that international trends must be analysed strategically as well as critically and that such analysis, for example through Critical Practitioner...

  16. Ground cross-modal impedance as a tool for analyzing ground/plate interaction and ground wave propagation.

    Science.gov (United States)

    Grau, L; Laulagnet, B

    2015-05-01

    An analytical approach is investigated to model ground-plate interaction based on modal decomposition and the two-dimensional Fourier transform. A finite rectangular plate subjected to flexural vibration is coupled with the ground and modeled with the Kirchhoff hypothesis. A Navier equation represents the stratified ground, assumed infinite in the x- and y-directions and free at the top surface. To obtain an analytical solution, modal decomposition is applied to the structure and a Fourier Transform is applied to the ground. The result is a new tool for analyzing ground-plate interaction to resolve this problem: ground cross-modal impedance. It allows quantifying the added-stiffness, added-mass, and added-damping from the ground to the structure. Similarity with the parallel acoustic problem is highlighted. A comparison between the theory and the experiment shows good matching. Finally, specific cases are investigated, notably the influence of layer depth on plate vibration.

  17. Grounding word learning in space.

    Directory of Open Access Journals (Sweden)

    Larissa K Samuelson

    Full Text Available Humans and objects, and thus social interactions about objects, exist within space. Words direct listeners' attention to specific regions of space. Thus, a strong correspondence exists between where one looks, one's bodily orientation, and what one sees. This leads to further correspondence with what one remembers. Here, we present data suggesting that children use associations between space and objects and space and words to link words and objects--space binds labels to their referents. We tested this claim in four experiments, showing that the spatial consistency of where objects are presented affects children's word learning. Next, we demonstrate that a process model that grounds word learning in the known neural dynamics of spatial attention, spatial memory, and associative learning can capture the suite of results reported here. This model also predicts that space is special, a prediction supported in a fifth experiment that shows children do not use color as a cue to bind words and objects. In a final experiment, we ask whether spatial consistency affects word learning in naturalistic word learning contexts. Children of parents who spontaneously keep objects in a consistent spatial location during naming interactions learn words more effectively. Together, the model and data show that space is a powerful tool that can effectively ground word learning in social contexts.

  18. Common Ground Between Three Cultures

    Directory of Open Access Journals (Sweden)

    Gloria Dunnivan

    2009-12-01

    Full Text Available The Triwizard program with Israel brought together students from three different communities: an Israeli Arab school, an Israeli Jewish school, and an American public school with few Jews and even fewer Muslims. The two Israeli groups met in Israel to find common ground and overcome their differences through dialogue and understanding. They communicated with the American school via technology such as video-conferencing, Skype, and emails. The program culminated with a visit to the U.S. The goal of the program was to embark upon a process that would bring about intercultural awareness and acceptance at the subjective level, guiding all involved to develop empathy and an insider's view of the other's culture. It was an attempt to have a group of Israeli high school students and a group of Arab Israeli students who had a fearful, distrustful perception of each other find common ground and become friends. TriWizard was designed to have participants begin a dialogue about issues, beliefs, and emotions based on the premise that cross-cultural training strategies that are effective in changing knowledge are those that engage the emotions, and actively develop empathy and an insider's views of another culture focused on what they have in common. Participants learned that they could become friends despite their cultural differences.

  19. Ground penetrating radar system and method for detecting an object on or below a ground surface

    NARCIS (Netherlands)

    De Jongth, R.; Yarovoy, A.; Schukin, A.

    2001-01-01

    Ground penetrating radar system for detecting objects (17) on or below a ground surface (18), comprising at least one transmit antenna (13) having a first foot print (14) at the ground surface, at least one receive antenna (15) having a second foot print (16) at the ground surface, and processing

  20. Transitions in midwestern ground water law

    International Nuclear Information System (INIS)

    Bowman, J.A.; Clark, G.R.

    1989-01-01

    The evolution of ground-water law in eight states in the Midwest (Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin) is examined, and a review of transitions in ground-water doctrines is presented. Two underlying themes in changing ground-water management are communicated. First, ground-water law is evolving from private property rules of capture based on the absolute ownership doctrines to rules requiring conservation and sharing of ground water as a public resource. Second, in both courts and state legislatures, a proactive role of ground-water management is emerging, again, with an emphasis on sharing. Both of these trends are apparent in the Midwest. In the last decade midwestern states have (1) seen significant shifts in court decisions on ground-water use with greater recognition of the reciprocal or mutually dependent nature of ground-water rights, and (2) seen increased legislative development of comprehensive ground-water management statutes that emphasize the reciprocal liabilities of ground-water use. These trends are examined and ground-water management programs discussed for eight states in the Midwest

  1. Transonic and supersonic ground effect aerodynamics

    Science.gov (United States)

    Doig, G.

    2014-08-01

    A review of recent and historical work in the field of transonic and supersonic ground effect aerodynamics has been conducted, focussing on applied research on wings and aircraft, present and future ground transportation, projectiles, rocket sleds and other related bodies which travel in close ground proximity in the compressible regime. Methods for ground testing are described and evaluated, noting that wind tunnel testing is best performed with a symmetry model in the absence of a moving ground; sled or rail testing is ultimately preferable, though considerably more expensive. Findings are reported on shock-related ground influence on aerodynamic forces and moments in and accelerating through the transonic regime - where force reversals and the early onset of local supersonic flow is prevalent - as well as more predictable behaviours in fully supersonic to hypersonic ground effect flows.

  2. Radon classification of building ground

    International Nuclear Information System (INIS)

    Slunga, E.

    1988-01-01

    The Laboratories of Building Technology and Soil Mechanics and Foundation Engineering at the Helsinki University of Technology in cooperation with The Ministry of the Environment have proposed a radon classification for building ground. The proposed classification is based on the radon concentration in soil pores and on the permeability of the foundation soil. The classification includes four radon classes: negligible, normal, high and very high. Depending on the radon class the radon-technical solution for structures is chosen. It is proposed that the classification be done in general terms in connection with the site investigations for the planning of land use and in more detail in connection with the site investigations for an individual house. (author)

  3. Navigating the grounded theory terrain. Part 1.

    Science.gov (United States)

    Hunter, Andrew; Murphy, Kathy; Grealish, Annmarie; Casey, Dympna; Keady, John

    2011-01-01

    The decision to use grounded theory is not an easy one and this article aims to illustrate and explore the methodological complexity and decision-making process. It explores the decision making of one researcher in the first two years of a grounded theory PhD study looking at the psychosocial training needs of nurses and healthcare assistants working with people with dementia in residential care. It aims to map out three different approaches to grounded theory: classic, Straussian and constructivist. In nursing research, grounded theory is often referred to but it is not always well understood. This confusion is due in part to the history of grounded theory methodology, which is one of development and divergent approaches. Common elements across grounded theory approaches are briefly outlined, along with the key differences of the divergent approaches. Methodological literature pertaining to the three chosen grounded theory approaches is considered and presented to illustrate the options and support the choice made. The process of deciding on classical grounded theory as the version best suited to this research is presented. The methodological and personal factors that directed the decision are outlined. The relative strengths of Straussian and constructivist grounded theories are reviewed. All three grounded theory approaches considered offer the researcher a structured, rigorous methodology, but researchers need to understand their choices and make those choices based on a range of methodological and personal factors. In the second article, the final methodological decision will be outlined and its research application described.

  4. Grounded Theory in Medical Education Research.

    Science.gov (United States)

    Tavakol, Mohsen; Torabi, Sima; Akbar Zeinaloo, Ali

    2006-12-01

    The grounded theory method provides a systematic way to generate theoretical constructs or concepts that illuminate psychosocial processes common to individual who have a similar experience of the phenomenon under investigation. There has been an increase in the number of published research reports that use the grounded theory method. However, there has been less medical education research, which is based on the grounded theory tradition. The purpose of this paper is to introduce basic tenants of qualitative research paradigm with specific reference to ground theory. The paper aims to encourage readers to think how they might possibly use the grounded theory method in medical education research and to apply such a method to their own areas of interest. The important features of a grounded theory as well as its implications for medical education research are explored. Data collection and analysis are also discussed. It seems to be reasonable to incorporate knowledge of this kind in medical education research.

  5. Suomi NPP Ground System Performance

    Science.gov (United States)

    Grant, K. D.; Bergeron, C.

    2013-12-01

    The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). JPSS will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The first satellite in the JPSS constellation, known as the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite, was launched on 28 October 2011, and is currently undergoing product calibration and validation activities. As products reach a beta level of maturity, they are made available to the community through NOAA's Comprehensive Large Array-data Stewardship System (CLASS). CGS's data processing capability processes the satellite data from the Joint Polar Satellite System satellites to provide environmental data products (including Sensor Data Records (SDRs) and Environmental Data Records (EDRs)) to NOAA and Department of Defense (DoD) processing centers operated by the United States government. CGS is currently processing and delivering SDRs and EDRs for Suomi NPP and will continue through the lifetime of the Joint Polar Satellite System programs. Following the launch and sensor activation phase of the Suomi NPP mission, full volume data traffic is now flowing from the satellite through CGS's C3, data processing, and data delivery systems. Ground system performance is critical for this operational system. As part of early system checkout, Raytheon measured all aspects of data acquisition, routing, processing, and delivery to ensure operational performance requirements are met, and will continue to be met throughout the mission. Raytheon developed a tool to measure, categorize, and

  6. 46 CFR 111.05-13 - Grounding connection.

    Science.gov (United States)

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-13 Grounding... power sources operating in parallel in the system. ...

  7. Grounded Theory in Medical Education Research

    OpenAIRE

    Tavakol, Mohsen; Torabi, Sima; Akbar Zeinaloo, Ali

    2009-01-01

    The grounded theory method provides a systematic way to generate theoretical constructs or concepts that illuminate psychosocial processes common to individual who have a similar expe­rience of the phenomenon under investigation. There has been an increase in the number of pub­lished research reports that use the grounded theory method. However, there has been less medical education research, which is based on the grounded theory tradition. The purpose of this paper is to introduce basic tena...

  8. The Hibernation of the oak Mildew

    NARCIS (Netherlands)

    Kerling, L.C.P.

    1966-01-01

    The oak mildew invaded Western Europa in the years 1908 and 1909. Since then this parasite, Microsphaera alphitoides Griff. & Maubl. (syn. M. quercina (Schw.) Burr.) has occurred regularly in the Netherlands on oak seedlings and oak coppice, mainly Quercus pedunculata Ehr. (syn. Q. robur L. ). After

  9. Ground Motion Models for Future Linear Colliders

    International Nuclear Information System (INIS)

    Seryi, Andrei

    2000-01-01

    Optimization of the parameters of a future linear collider requires comprehensive models of ground motion. Both general models of ground motion and specific models of the particular site and local conditions are essential. Existing models are not completely adequate, either because they are too general, or because they omit important peculiarities of ground motion. The model considered in this paper is based on recent ground motion measurements performed at SLAC and at other accelerator laboratories, as well as on historical data. The issues to be studied for the models to become more predictive are also discussed

  10. Management of ground water using isotope techniques

    International Nuclear Information System (INIS)

    Romani, Saleem

    2004-01-01

    Ground water play a major role in national economy and sustenance of life and environment. Prevalent water crisis in India includes falling water table, water quality deterioration, water logging and salinity. Keeping in view the increasing thrust on groundwater resources and the present scenario of availability vis-a vis demand there is a need to reorient our approach to ground water management. The various ground water management options require proper understanding of ground water flow system. Isotopes are increasingly being applied in hydrogeological investigations as a supplementary tool for assessment of aquifer flow and transport characteristics. Isotope techniques coupled with conventional hydrogeological and hydrochemical methods can bring in greater accuracy in the conceptualization of hydrogeological control mechanism. The use of isotope techniques in following areas can certainly be of immense help in implementing various ground water management options in an efficient manner. viz.Interaction between the surface water - groundwater systems to plan conjunctive use of surface and ground water. Establishing hydraulic interconnections between the aquifers in a multi aquifer system. Depth of circulation of water and dating of ground water. Demarcating ground water recharge and discharge areas. Plan ground water development in coastal aquifers to avoid sea water ingress. Development of flood plain aquifer. (author)

  11. Using periodicity to mitigate ground vibration

    DEFF Research Database (Denmark)

    Andersen, Lars Vabbersgaard

    2015-01-01

    Introduction of trenches, barriers and wave impeding blocks on the transmission path between a source and receiver can be used for mitigation of ground vibration. However, to be effective a barrier must have a depth of about one wavelength of the waves to be mitigated. Hence, while great reductions......: A soil with periodic stiffening (ground improvement) and a ground with periodic changes in the surface elevation obtained by artificial landscaping. By means of a two-dimensional finite-element model, the stiffness and mass matrices are determined for a single cell of the ground with horizonal...

  12. Measurement of ground motion in various sites

    International Nuclear Information System (INIS)

    Bialowons, W.; Amirikas, R.; Bertolini, A.; Kruecker, D.

    2007-04-01

    Ground vibrations may affect low emittance beam transport in linear colliders, Free Electron Lasers (FEL) and synchrotron radiation facilities. This paper is an overview of a study program to measure ground vibrations in various sites which can be used for site characterization in relation to accelerator design. Commercial broadband seismometers have been used to measure ground vibrations and the resultant database is available to the scientific community. The methodology employed is to use the same equipment and data analysis tools for ease of comparison. This database of ground vibrations taken in 19 sites around the world is first of its kind. (orig.)

  13. Urban ambiances as common ground?

    Directory of Open Access Journals (Sweden)

    Jean-Paul Thibaud

    2014-07-01

    Full Text Available The aim of this paper is to point out various arguments which question ambiance as a common ground of everyday urban experience. Such a project involves four major points. First, we have to move beyond the exclusive practical aspects of everyday life and bring the sensory to the forefront. Under such conditions, sensory cultures emerge where feeling and acting come together. Second, we must put common experience into perspectiveby initiating a dual dynamics of socialising the sensory and sensitising social life. Ambiances involve a complex web comprised of an ‘existential’ dimension (empathy with the ambient world, a ‘contextual’ dimension (degree of presence in the situation, and an ‘interactional’ dimension (forms of sociability expressed in the tonality. Third, we have to initiate a political ecology of ambiances in order to better understand how ambiances deal with fundamental design and planning issues. Far from being neutral, the notion of ambiance appears to be bound up with the socio-aesthetic strategies underpinning changes to the sensory urban environment of the future. Fourth, we have to question what in situ experience is all about. Three major research pointers enable to address this issue: the embodiment of situated experiences, the porous nature of sensory spaces, and the sensory efficiency of the build environment. Ambiances sensitize urban design as well as social lifeforms.

  14. Composite liners protect ground water

    Energy Technology Data Exchange (ETDEWEB)

    Tatzky, R; August, H

    1987-12-01

    For about 10 years flexible membrane liners (FMLs) have been used as bottom liners to protect ground water in the vicinity of waste sites. But a permeation (absorption, diffusion, desorption) of chemical liquids, e.g. hydrocarbons (HC) and chlorinated hydrocarbons (CHC) will generally occur. The rates of permeation depend, first of all, on the chemical affinity, the thickness of the FML and the boundary conditions. In order to improve the barrier quality of polymeric membranes, it is necessary to study the transport processes of HC and CHC through the polymeric materials. Long-term tests with composite liners are additionally carried out. These are liners which consist of two components, flexible membrane and natural soil liner (recompacted clay, bentonite-soil mixtures). Laboratory studies show that with composite liners a perfect sealing of waste sites may be possible. Test methods for measuring permeation rates of HC and CHC through polymeric membranes and methods of testing for the development of composite liner systems are presented. (orig.)

  15. 2011 Ground Testing Highlights Article

    Science.gov (United States)

    Ross, James C.; Buchholz, Steven J.

    2011-01-01

    Two tests supporting development of the launch abort system for the Orion MultiPurpose Crew Vehicle were run in the NASA Ames Unitary Plan wind tunnel last year. The first test used a fully metric model to examine the stability and controllability of the Launch Abort Vehicle during potential abort scenarios for Mach numbers ranging from 0.3 to 2.5. The aerodynamic effects of the Abort Motor and Attitude Control Motor plumes were simulated using high-pressure air flowing through independent paths. The aerodynamic effects of the proximity to the launch vehicle during the early moments of an abort were simulated with a remotely actuated Service Module that allowed the position relative to the Crew Module to be varied appropriately. The second test simulated the acoustic environment around the Launch Abort Vehicle caused by the plumes from the 400,000-pound thrust, solid-fueled Abort Motor. To obtain the proper acoustic characteristics of the hot rocket plumes for the flight vehicle, heated Helium was used. A custom Helium supply system was developed for the test consisting of 2 jumbo high-pressure Helium trailers, a twelve-tube accumulator, and a 13MW gas-fired heater borrowed from the Propulsion Simulation Laboratory at NASA Glenn Research Center. The test provided fluctuating surface pressure measurements at over 200 points on the vehicle surface that have now been used to define the ground-testing requirements for the Orion Launch Abort Vehicle.

  16. Infrasound from ground to space

    Science.gov (United States)

    Bowman, Daniel Charles

    Acoustic detector networks are usually located on the Earth's surface. However, these networks suffer from shortcomings such as poor detection range and pervasive wind noise. An alternative is to deploy acoustic sensors on high altitude balloons. In theory, such platforms can resolve signals arriving from great distances, acquire others that never reach the surface at all, and avoid wind noise entirely. This dissertation focuses on scientific advances, instrumentation, and analytical techniques resulting from the development of such sensor arrays. Results from infrasound microphones deployed on balloon flights in the middle stratosphere are described, and acoustic sources such as the ocean microbarom and building ventilation systems are discussed. Electromagnetic noise originating from the balloon, flight system, and other payloads is shown to be a pervasive issue. An experiment investigating acoustic sensor calibration at low pressures is presented, and implications for high altitude recording are considered. Outstanding challenges and opportunities in sound measurement using sensors embedded in the free atmosphere are outlined. Acoustic signals from field scale explosions designed to emulate volcanic eruptions are described, and their generation mechanisms modeled. Wave forms recorded on sensors suspended from tethered helium balloons are compared with those detected on ground stations during the experiment. Finally, the Hilbert-Huang transform, a high time resolution spectral analysis method for nonstationary and nonlinear time series, is presented.

  17. Visiting Vehicle Ground Trajectory Tool

    Science.gov (United States)

    Hamm, Dustin

    2013-01-01

    The International Space Station (ISS) Visiting Vehicle Group needed a targeting tool for vehicles that rendezvous with the ISS. The Visiting Vehicle Ground Trajectory targeting tool provides the ability to perform both realtime and planning operations for the Visiting Vehicle Group. This tool provides a highly reconfigurable base, which allows the Visiting Vehicle Group to perform their work. The application is composed of a telemetry processing function, a relative motion function, a targeting function, a vector view, and 2D/3D world map type graphics. The software tool provides the ability to plan a rendezvous trajectory for vehicles that visit the ISS. It models these relative trajectories using planned and realtime data from the vehicle. The tool monitors ongoing rendezvous trajectory relative motion, and ensures visiting vehicles stay within agreed corridors. The software provides the ability to update or re-plan a rendezvous to support contingency operations. Adding new parameters and incorporating them into the system was previously not available on-the-fly. If an unanticipated capability wasn't discovered until the vehicle was flying, there was no way to update things.

  18. Ground Motion Prediction Models for Caucasus Region

    Science.gov (United States)

    Jorjiashvili, Nato; Godoladze, Tea; Tvaradze, Nino; Tumanova, Nino

    2016-04-01

    Ground motion prediction models (GMPMs) relate ground motion intensity measures to variables describing earthquake source, path, and site effects. Estimation of expected ground motion is a fundamental earthquake hazard assessment. The most commonly used parameter for attenuation relation is peak ground acceleration or spectral acceleration because this parameter gives useful information for Seismic Hazard Assessment. Since 2003 development of Georgian Digital Seismic Network has started. In this study new GMP models are obtained based on new data from Georgian seismic network and also from neighboring countries. Estimation of models is obtained by classical, statistical way, regression analysis. In this study site ground conditions are additionally considered because the same earthquake recorded at the same distance may cause different damage according to ground conditions. Empirical ground-motion prediction models (GMPMs) require adjustment to make them appropriate for site-specific scenarios. However, the process of making such adjustments remains a challenge. This work presents a holistic framework for the development of a peak ground acceleration (PGA) or spectral acceleration (SA) GMPE that is easily adjustable to different seismological conditions and does not suffer from the practical problems associated with adjustments in the response spectral domain.

  19. 14 CFR 415.117 - Ground safety.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Ground safety. 415.117 Section 415.117... TRANSPORTATION LICENSING LAUNCH LICENSE Safety Review and Approval for Launch of an Expendable Launch Vehicle From a Non-Federal Launch Site § 415.117 Ground safety. (a) General. An applicant's safety review...

  20. 49 CFR 234.213 - Grounds.

    Science.gov (United States)

    2010-10-01

    ... Maintenance Standards § 234.213 Grounds. Each circuit that affects the proper functioning of a highway-rail... in the circuit. This requirement does not apply to: circuits that include track rail; alternating current power distribution circuits that are grounded in the interest of safety; and common return wires...

  1. Ground-based observations of exoplanet atmospheres

    NARCIS (Netherlands)

    Mooij, Ernst Johan Walter de

    2011-01-01

    This thesis focuses on the properties of exoplanet atmospheres. The results for ground-based near-infrared secondary eclipse observations of three different exoplanets, TrES-3b, HAT-P-1b and WASP-33b, are presented which have been obtained with ground-based telescopes as part of the GROUSE project.

  2. Puzzling the Picture Using Grounded Theory

    Science.gov (United States)

    Bennett, Elisabeth E.

    2016-01-01

    Since the first publication by Glaser and Strauss in 1967, Grounded Theory has become a highly influential research approach in the social sciences. The approach provides techniques and coding strategies for building theory inductively from the "ground up" as concepts within the data earn relevance into an evolving substantive theory.…

  3. Procedures for ground-water investigations

    International Nuclear Information System (INIS)

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program

  4. River as a part of ground battlefield

    Science.gov (United States)

    Vračar, Miodrag S.; Pokrajac, Ivan; Okiljević, Predrag

    2013-05-01

    The rivers are in some circumstances part of the ground battlefield. Microseisms induced at the riverbed or ground at the river surrounding might be consequence of military activities (military ground transports, explosions, troop's activities, etc). Vibrations of those fluid-solid structures are modeled in terms of solid displacement and change of fluid pressure. This time varying fluid pressure in river, which originates from ground microseisms, is possible to detect with hydrophones. Therefore, hydroacoustic measurements in rivers enables detecting, identification and localization various types of military noisy activities at the ground as and those, which origin is in the river water (hydrodynamics of water flow, wind, waves, river vessels, etc). In this paper are presented river ambient noise measurements of the three great rivers: the Danube, the Sava and the Tisa, which flows in north part of Serbia in purpose to establish limits in detection of the ground vibrations in relatively wide frequency range from zero to 20 kHz. To confirm statement that the river is a part of ground battlefield, and that hydroacoustic noise is possible to use in detecting and analyzing ground microseisms induced by civil or military activities, some previous collected data of hydroacoustic noise measurement in the rivers are used. The data of the river ambient noise include noise induced by civil engineering activities, that ordinary take place in large cities, noise that produced ships and ambient noise of the river when human activities are significantly reduced. The poly spectral method was used in analysis such events.

  5. Discussing the theological grounds of moral principles.

    Science.gov (United States)

    Heller, Jan C

    2005-01-01

    Discussing the theological beliefs that ground Catholic moral principles can make some people uncomfortable, even while others will appreciate it. But these reactions will sometimes be revealed not as the emotions they are, but as objections to the relative independence or dependence of morality on foundational beliefs. In the end, context should dictate whether one displays the theological beliefs that ground Catholic moral principles.

  6. Ground Truth Annotation in T Analyst

    DEFF Research Database (Denmark)

    2015-01-01

    This video shows how to annotate the ground truth tracks in the thermal videos. The ground truth tracks are produced to be able to compare them to tracks obtained from a Computer Vision tracking approach. The program used for annotation is T-Analyst, which is developed by Aliaksei Laureshyn, Ph...

  7. Ambulatory Measurement of Ground Reaction Forces

    NARCIS (Netherlands)

    Veltink, Peter H.; Liedtke, Christian; Droog, Ed

    2004-01-01

    The measurement of ground reaction forces is important in the biomechanical analysis of gait and other motor activities. It is the purpose of this study to show the feasibility of ambulatory measurement of ground reaction forces using two six degrees of freedom sensors mounted under the shoe. One

  8. Enhanced spatial resolution on figures versus grounds.

    Science.gov (United States)

    Hecht, Lauren N; Cosman, Joshua D; Vecera, Shaun P

    2016-07-01

    Much is known about the cues that determine figure-ground assignment, but less is known about the consequences of figure-ground assignment on later visual processing. Previous work has demonstrated that regions assigned figural status are subjectively more shape-like and salient than background regions. The increase in subjective salience of figural regions could be caused by a number of processes, one of which may be enhanced perceptual processing (e.g., an enhanced neural representation) of figures relative to grounds. We explored this hypothesis by having observers perform a perceptually demanding spatial resolution task in which targets appeared on either figure or ground regions. To rule out a purely attentional account of figural salience, observers discriminated targets on the basis of a region's color (red or green), which was equally likely to define the figure or the ground. The results of our experiments showed that targets appearing on figures were discriminated more accurately than those appearing in ground regions. In addition, targets appearing on figures were discriminated better than those presented in regions considered figurally neutral, but targets appearing within ground regions were discriminated more poorly than those appearing in figurally neutral regions. Taken together, our findings suggest that when two regions share a contour, regions assigned as figure are perceptually enhanced, whereas regions assigned as ground are perceptually suppressed.

  9. ECRB ALCOVE AND NICHE GROUND SUPPORT ANALYSIS

    International Nuclear Information System (INIS)

    J.W. Keifer

    1999-01-01

    The purpose of the analysis is to provide design bases for Enhanced Characterization of the Repository Block (ECRB) alcove and niche ground support drawings. The objective is to evaluate the ESF Alcove Ground Support Analysis (Ref 5.1) to determine if the calculations technically bound the ECRB alcoves and to address specific differences in the conditions and constraints

  10. Young Children's Understanding of Cultural Common Ground

    Science.gov (United States)

    Liebal, Kristin; Carpenter, Malinda; Tomasello, Michael

    2013-01-01

    Human social interaction depends on individuals identifying the common ground they have with others, based both on personally shared experiences and on cultural common ground that all members of the group share. We introduced 3- and 5-year-old children to a culturally well-known object and a novel object. An experimenter then entered and asked,…

  11. Grounded Theory Methodology: Positivism, Hermeneutics, and Pragmatism

    Science.gov (United States)

    Age, Lars-Johan

    2011-01-01

    Glaserian grounded theory methodology, which has been widely adopted as a scientific methodology in recent decades, has been variously characterised as "hermeneutic" and "positivist." This commentary therefore takes a different approach to characterising grounded theory by undertaking a comprehensive analysis of: (a) the philosophical paradigms of…

  12. 30 CFR 75.801 - Grounding resistors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding resistors. 75.801 Section 75.801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution § 75.801 Grounding...

  13. Enhanced spatial resolution on figures versus grounds

    Science.gov (United States)

    Hecht, Lauren N.; Cosman, Joshua D.; Vecera, Shaun P.

    2016-01-01

    Much is known about the cues that determine figure-ground assignment, but less is known about the consequences of figure-ground assignment on later visual processing. Previous work has demonstrated that regions assigned figural status are subjectively more shape-like and salient than background regions. The increase in subjective salience of figural regions could be caused by a number of processes, one of which may be enhanced perceptual processing (e.g., an enhanced neural representation) of figures relative to grounds. We explored this hypothesis by having observers perform a perceptually demanding spatial resolution task in which targets appeared either on figure or ground regions. To rule out a purely attentional account of figural salience, observers discriminated targets on the basis of a region’s color (red or green), which was equally likely to define the figure or the ground. The results of our experiments show that targets appearing on figures were discriminated more accurately than those appearing in ground regions. In addition, targets appearing on figures were discriminated better than those presented in regions considered figurally neutral, but targets appearing within ground regions were discriminated more poorly than those appearing in figurally neutral regions. Taken together, our findings suggest that when two regions share a contour, regions assigned as figure are perceptually enhanced, whereas regions assigned as grounds are perceptually suppressed. PMID:27048441

  14. Building Grounded Theory in Entrepreneurship Research

    DEFF Research Database (Denmark)

    Mäkelä, Markus; Turcan, Romeo V.

    2007-01-01

    In this chapter we describe the process of building of theory from data (Glaser and Strauss 1967; Strauss and Corbin 1998). We discuss current grounded theory in relation to research in entrepreneurship and point out directions and potential improvements for further research in this field....... The chapter has two goals. First, we wish to provide an explicit paradigmatic positioning of the grounded theory methodology, discussing the most relevant views of ontology and epistemology that can be used as alternative starting points for conducting grounded theory research. While the chapter introduces...... our approach to grounded theory, we acknowledge the existence of other approaches and try to locate our approach in relation to them. As an important part of this discussion, we take a stand on how to usefully define ‘grounded theory’ and ‘case study research’. Second, we seek to firmly link our...

  15. Pollutant infiltration and ground water management

    International Nuclear Information System (INIS)

    1993-01-01

    Following a short overview of hazard potentials for ground water in Germany, this book, which was compiled by the technical committee of DVWK on ground water use, discusses the natural scientific bases of pollutant movement to and in ground water. It points out whether and to what extent soil/ground water systems can be protected from harmful influences, and indicates relative strategies. Two zones are distinguished: the unsaturated zone, where local defence and remedial measures are frequently possible, and the saturated zone. From the protective function of geological systems, which is always pollutant-specific, criteria are derived for judging the systems generally, or at least regarding entire classes of pollutants. Finally, the impact of the infiltration of pollutants into ground water on its use as drinking water is pointed out and an estimate of the cost of remedial measures is given. (orig.) [de

  16. Modernization of the Cassini Ground System

    Science.gov (United States)

    Razo, Gus; Fujii, Tammy

    2014-01-01

    The Cassini Spacecraft and its ground system have been operational for over 16 years. Modernization presents several challenges due to the personnel, processes, and tools already invested and embedded into the current ground system structure. Every mission's ground system has its own unique complexities and challenges, involving various organizational units. As any mission from its inception to its execution, schedules are always tight. This forces GDS engineers to implement a working ground system that is not necessarily fully optimized. Ground system challenges increase as technology evolves and cyber threats become more sophisticated. Cassini's main challenges were due to its ground system existing before many security requirements were levied on the multi-mission tools and networks. This caused a domino effect on Cassini GDS tools that relied on outdated technological features. In the aerospace industry reliable and established technology is preferred over innovative yet less proven technology. Loss of data for a spacecraft mission can be catastrophic; therefore, there is a reluctance to make changes and updates to the ground system. Nevertheless, all missions and associated teams face the need to modernize their processes and tools. Systems development methods from well-known system analysis and design principles can be applied to many missions' ground systems. Modernization should always be considered, but should be done in such a way that it does not affect flexibility nor interfere with established practices. Cassini has accomplished a secure and efficient ground data system through periodic updates. The obstacles faced while performing the modernization of the Cassini ground system will be outlined, as well as the advantages and challenges that were encountered.

  17. Hanford site ground water protection management plan

    International Nuclear Information System (INIS)

    1994-10-01

    Ground water protection at the Hanford Site consists of preventative and remedial measures that are implemented in compliance with a variety of environmental regulations at local, state, and federal levels. These measures seek to ensure that the resource can sustain a broad range of beneficial uses. To effectively coordinate and ensure compliance with applicable regulations, the U.S. Department of Energy has issued DOE Order 5400.1 (DOE 1988a). This order requires all U.S. Department of Energy facilities to prepare separate ground water protection program descriptions and plans. This document describes the Ground Water Protection Management Plan (GPMP) for the Hanford Site located in the state of Washington. DOE Order 5400.1 specifies that the GPMP covers the following general topical areas: (1) documentation of the ground water regime; (2) design and implementation of a ground water monitoring program to support resource management and comply with applicable laws and regulations; (3) a management program for ground water protection and remediation; (4) a summary and identification of areas that may be contaminated with hazardous waste; (5) strategies for controlling hazardous waste sources; (6) a remedial action program; and (7) decontamination, decommissioning, and related remedial action requirements. Many of the above elements are currently covered by existing programs at the Hanford Site; thus, one of the primary purposes of this document is to provide a framework for coordination of existing ground water protection activities. The GPMP provides the ground water protection policy and strategies for ground water protection/management at the Hanford Site, as well as an implementation plan to improve coordination of site ground water activities

  18. Navigating the grounded theory terrain. Part 2.

    Science.gov (United States)

    Hunter, Andrew; Murphy, Kathy; Grealish, Annmarie; Casey, Dympna; Keady, John

    2011-01-01

    In this paper, the choice of classic grounded theory will be discussed and justified in the context of the first author's PhD research. The methodological discussion takes place within the context of PhD research entitled: Development of a stakeholder-led framework for a structured education programme that will prepare nurses and healthcare assistants to deliver a psychosocial intervention for people with dementia. There is a lack of research and limited understanding of the effect of psychosocial interventions on people with dementia. The first author thought classic grounded theory a suitable research methodology to investigate as it is held to be ideal for areas of research where there is little understanding of the social processes at work. The literature relating to the practical application of classic grounded theory is illustrated using examples relating to four key grounded theory components: Theory development: using constant comparison and memoing, Methodological rigour, Emergence of a core category, Inclusion of self and engagement with participants. Following discussion of the choice and application of classic grounded theory, this paper explores the need for researchers to visit and understand the various grounded theory options. This paper argues that researchers new to grounded theory must be familiar with and understand the various options. The researchers will then be able to apply the methodologies they choose consistently and critically. Doing so will allow them to develop theory rigorously and they will ultimately be able to better defend their final methodological destinations.

  19. Essential methodological considerations when using grounded theory.

    Science.gov (United States)

    Achora, Susan; Matua, Gerald Amandu

    2016-07-01

    To suggest important methodological considerations when using grounded theory. A research method widely used in nursing research is grounded theory, at the centre of which is theory construction. However, researchers still struggle with some of its methodological issues. Although grounded theory is widely used to study and explain issues in nursing practice, many researchers are still failing to adhere to its rigorous standards. Researchers should articulate the focus of their investigations - the substantive area of interest as well as the focal population. This should be followed by a succinct explanation of the strategies used to collect and analyse data, supported by clear coding processes. Finally, the resolution of the core issues, including the core category and related categories, should be explained to advance readers' understanding. Researchers should endeavour to understand the tenets of grounded theory. This enables 'neophytes' in particular to make methodological decisions that will improve their studies' rigour and fit with grounded theory. This paper complements the current dialogue on improving the understanding of grounded theory methodology in nursing research. The paper also suggests important procedural decisions researchers need to make to preserve their studies' scientific merit and fit with grounded theory.

  20. Competition-strength-dependent ground suppression in figure-ground perception.

    Science.gov (United States)

    Salvagio, Elizabeth; Cacciamani, Laura; Peterson, Mary A

    2012-07-01

    Figure-ground segregation is modeled as inhibitory competition between objects that might be perceived on opposite sides of borders. The winner is the figure; the loser is suppressed, and its location is perceived as shapeless ground. Evidence of ground suppression would support inhibitory competition models and would contribute to explaining why grounds are shapeless near borders shared with figures, yet such evidence is scarce. We manipulated whether competition from potential objects on the ground side of figures was high (i.e., portions of familiar objects were potentially present there) or low (novel objects were potentially present). We predicted that greater competition would produce more ground suppression. The results of two experiments in which suppression was assessed via judgments of the orientation of target bars confirmed this prediction; a third experiment showed that ground suppression is short-lived. Our findings support inhibitory competition models of figure assignment, in particular, and models of visual perception entailing feedback, in general.

  1. Ground Water in the Anchorage Area, Alaska--Meeting the Challenges of Ground-Water Sustainability

    Science.gov (United States)

    Moran, Edward H.; Galloway, Devin L.

    2006-01-01

    Ground water is an important component of Anchorage's water supply. During the 1970s and early 80s when ground water extracted from aquifers near Ship Creek was the principal source of supply, area-wide declines in ground-water levels resulted in near record low streamflows in Ship Creek. Since the importation of Eklutna Lake water in the late 1980s, ground-water use has been reduced and ground water has contributed 14-30 percent of the annual supply. As Anchorage grows, given the current constraints on the Eklutna Lake water availability, the increasing demand for water could place an increasing reliance on local ground-water resources. The sustainability of Anchorage's ground-water resources challenges stakeholders to develop a comprehensive water-resources management strategy.

  2. Ground-Water Protection and Monitoring Program

    International Nuclear Information System (INIS)

    Dresel, P.E.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the ground-water protection and monitoring program strategy for the Hanford Site in 1994. Two of the key elements of this strategy are to (1) protect the unconfined aquifer from further contamination, and (2) conduct a monitoring program to provide early warning when contamination of ground water does occur. The monitoring program at Hanford is designed to document the distribution and movement of existing ground-water contamination and provides a historical baseline for evaluating current and future risk from exposure to the contamination and for deciding on remedial action options

  3. Ground-Water Protection and Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, P.E.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the ground-water protection and monitoring program strategy for the Hanford Site in 1994. Two of the key elements of this strategy are to (1) protect the unconfined aquifer from further contamination, and (2) conduct a monitoring program to provide early warning when contamination of ground water does occur. The monitoring program at Hanford is designed to document the distribution and movement of existing ground-water contamination and provides a historical baseline for evaluating current and future risk from exposure to the contamination and for deciding on remedial action options.

  4. Biodiesel Production from Spent Coffee Grounds

    Science.gov (United States)

    Blinová, Lenka; Bartošová, Alica; Sirotiak, Maroš

    2017-06-01

    The residue after brewing the spent coffee grounds is an oil-containing waste material having a potential of being used as biodiesel feedstock. Biodiesel production from the waste coffee grounds oil involves collection and transportation of coffee residue, drying, oil extraction, and finally production of biodiesel. Different methods of oil extraction with organic solvents under different conditions show significant differences in the extraction yields. In the manufacturing of biodiesel from coffee oil, the level of reaction completion strongly depends on the quality of the feedstock oil. This paper presents an overview of oil extraction and a method of biodiesel production from spent coffee grounds.

  5. 30 CFR 57.3360 - Ground support use.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Ground support use. 57.3360 Section 57.3360... and Support-Underground Only § 57.3360 Ground support use. Ground support shall be used where ground conditions, or mining experience in similar ground conditions in the mine, indicate that it is necessary...

  6. Ground use by northern muriquis (Brachyteles hypoxanthus).

    Science.gov (United States)

    Mourthé, Italo M C; Guedes, Danusa; Fidelis, Janaína; Boubli, Jean P; Mendes, Sérgio L; Strier, Karen B

    2007-06-01

    Many arboreal primates descend to the ground, a custom that may occur more frequently in disturbed habitats, and in the presence of researchers to whom the primates are habituated. In this paper, we describe opportunistic observations of ground use in two groups of northern muriquis (Brachyteles hypoxanthus) at the RPPN Feliciano Miguel Abdala, Minas Gerais, Brazil. Members of both groups were observed drinking, resting, feeding, playing, and traveling on the ground to different degrees, and variation in the levels of habituation of the two groups may be responsible for the differences in the distribution of their terrestrial activities. The potential increase in vulnerability to predation or disease owing to ground use has implications for the conservation of this critically endangered species. (c) 2007 Wiley-Liss, Inc.

  7. Low ground clearance vehicle detection and warning.

    Science.gov (United States)

    2015-06-01

    A Low Ground Clearance Vehicle Detection : System (LGCVDS) determines if a commercial : motor vehicle can successfully clear a highwayrail : grade crossing and notifies the driver when : his or her vehicle cannot safely traverse the : crossing. That ...

  8. Puerto Rico Above Ground Biomass Map, 2000

    Data.gov (United States)

    U.S. Environmental Protection Agency — This image dataset details the U.S. Commonwealth of Puerto Rico above-ground forest biomass (AGB) (baseline 2000) developed by the United States (US) Environmental...

  9. Formation keeping of unmanned ground vehicles

    Directory of Open Access Journals (Sweden)

    Muangmin Kamonwan

    2017-01-01

    Full Text Available Controlling motions of an unmanned ground vehicle becomes more popular in real world practices. Its application is useful for household chores, military services, medical purposes, and industrial revolutions, etc. An analysis of motions by using the Fundamental Equations of Constrained Motion (FECM is one effective tool to determine the motions. Its conceptualization is done in three-step procedure as follows: (I Determining an unconstrained motion (II Assigning constraint equations and (III Computing a constrained motion. The equations of motion obtained are expressed as liner functions of acceleration. Then other kinematical information of the unmanned ground vehicles can be obtained by integration its acceleration. In this work, the FECM is used as a tool to analyze motions of a group of unmanned ground vehicles in various forms. The simulation results show that control forces obtained from the approach can regulate motions of unmanned ground vehicles to maneuver in desired formations.

  10. Identifying structural damage with ground penetrating radar

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2008-07-01

    Full Text Available Ground penetrating radar (GPR) and electrical resistance tomography (ERT) surveys were conducted in an urban environment in an attempt to identify the cause of severe structural damage to a historically significant residential property...

  11. Solid waste burial grounds interim safety analysis

    International Nuclear Information System (INIS)

    Saito, G.H.

    1994-01-01

    This Interim Safety Analysis document supports the authorization basis for the interim operation and restrictions on interim operations for the near-surface land disposal of solid waste in the Solid Waste Burial Grounds. The Solid Waste Burial Grounds Interim Safety Basis supports the upgrade progress for the safety analysis report and the technical safety requirements for the operations in the Solid Waste Burial Grounds. Accident safety analysis scenarios have been analyzed based on the significant events identified in the preliminary hazards analysis. The interim safety analysis provides an evaluation of the operations in the Solid Waste Burial Grounds to determine if the radiological and hazardous material exposures will be acceptable from an overall health and safety standpoint to the worker, the onsite personnel, the public, and the environment

  12. 49 CFR 236.2 - Grounds.

    Science.gov (United States)

    2010-10-01

    ... circuit, except circuits which include any track rail and except the common return wires of single-wire, single-break, signal control circuits using a grounded common, and alternating current power distribution...

  13. (ajst) effects of ground insulation and greenhouse

    African Journals Online (AJOL)

    NORBERT OPIYO AKECH

    and quality of biogas generation from dairy cattle dung. The effects ... Therefore ground insulation of plastic biogas digester under greenhouse conditions significantly enhances ..... The low values obtained did not suggest failure of the system ...

  14. Ground-water monitoring under RCRA

    International Nuclear Information System (INIS)

    Coalgate, J.

    1993-11-01

    In developing a regulatory strategy for the disposal of hazardous waste under the Resource Conservation and Recovery Act (RCRA), protection of ground-water resources was the primary goal of the Environmental Protection Agency (EPA). EPA's ground-water protection strategy seeks to minimize the potential for hazardous wastes and hazardous constituents in waste placed in land disposel units to migrate into the environment. This is achieved through liquids management (limiting the placement of liquid wastes in or on the land, requiring the use of liners beneath waste, installing leachate collection systems and run-on and run-off controls, and covering wastes at closure). Ground-water monitoring serves to detect any failure in EPA's liquids management strategy so that ground-water contamination can be detected and addressed as soon as possible

  15. Section 10: Ground Water - Waste Characteristics & Targets

    Science.gov (United States)

    HRS Training. The waste characteristics factor category in the ground water pathway is made up of two components: the toxicity/mobility of the most hazardous substance associated with the site and the hazardous waste quantity at the site.

  16. Solid waste burial grounds interim safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Saito, G.H.

    1994-10-01

    This Interim Safety Analysis document supports the authorization basis for the interim operation and restrictions on interim operations for the near-surface land disposal of solid waste in the Solid Waste Burial Grounds. The Solid Waste Burial Grounds Interim Safety Basis supports the upgrade progress for the safety analysis report and the technical safety requirements for the operations in the Solid Waste Burial Grounds. Accident safety analysis scenarios have been analyzed based on the significant events identified in the preliminary hazards analysis. The interim safety analysis provides an evaluation of the operations in the Solid Waste Burial Grounds to determine if the radiological and hazardous material exposures will be acceptable from an overall health and safety standpoint to the worker, the onsite personnel, the public, and the environment.

  17. QA CLASSIFICATION ANALYSIS OF GROUND SUPPORT SYSTEMS

    International Nuclear Information System (INIS)

    D. W. Gwyn

    1996-01-01

    The purpose and objective of this analysis is to determine if the permanent function Ground Support Systems (CI: BABEEOOOO) are quality-affecting items and if so, to establish the appropriate Quality Assurance (QA) classification

  18. Review Essay: A Journey through Grounded Theory

    Directory of Open Access Journals (Sweden)

    Paula Krüger

    2007-01-01

    Full Text Available In "Constructing Grounded Theory", Kathy CHARMAZ guides the reader through the research process. Starting with a look back at the history of grounded theory, she explains how to gather rich data, code it, write memos, and compose the first draft. Through various examples from her own research CHARMAZ provides the reader not only with a theoretical description of how to construct a grounded theory but also with a way of seeing how new questions emerge from the data and new theory is built from it. She highlights central concepts, definitions, and useful questions, and offers the reader flexible guidelines to design and conduct a research project. Because of this, the book will be very useful for novices as well as for experts and (PhD- students in the late stages of their theses; it is a must-have for everyone who works with/on (constructivist grounded theory. URN: urn:nbn:de:0114-fqs0701256

  19. Ground Control for Emplacement Drifts for LA

    International Nuclear Information System (INIS)

    Y. Sun

    2004-01-01

    The purpose of this calculation is to analyze the stability of repository emplacement drifts during the preclosure period, and to provide a final ground support method for emplacement drifts for the License Application (LA). The scope of the work includes determination of input parameter values and loads, selection of appropriate process and methods for the calculation, application of selected methods, such as empirical or analytical, to the calculation, development and execution of numerical models, and evaluation of results. Results from this calculation are limited to use for design of the emplacement drifts and the final ground support system installed in these drifts. The design of non-emplacement openings and their ground support systems is covered in the ''Ground Control for Non-Emplacement Drifts for LA'' (BSC 2004c)

  20. Ground Enterprise Management System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Spacecraft ground systems are on the cusp of achieving "plug-and-play" capability, i.e., they are approaching the state in which the various components can be...

  1. Traditional behaviour and fidelity to caribou calving grounds by barren-ground caribou

    Directory of Open Access Journals (Sweden)

    Anne Gunn

    1986-06-01

    Full Text Available Evidence for the fidelity of female barren-ground caribou (Rangifer tarandus spp. of each herd to specific calving grounds is convincing. Involvement of learned behaviour in the annual return of those cows to the same calving grounds implies such actions are a form of «traditional» behaviour. Even wide variations in population size have not yet knowingly led to marked changes in size or location of calving grounds or prolonged abandonment of established ones. Rarely is the adoption of new calving grounds reported and emigration to another herd's calving ground or interchange between calving grounds has not yet been unequivocally documented. The calving experience of individual caribou and environmental pressures may modify the cow's use patterns of her calving grounds. The current definition of herds based on traditional calving grounds may require modification, if increasing caribou numbers result in changes in traditions. However, current data do not contradict either the fidelity to traditional calving grounds or the concept of herd identity based on that fidelity.

  2. Seven methods to measure ground moisture

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The correct irrigation methods are of great importance to the deciduous fruit grower. The article discusses seven methods for the measuring of ground humidity. These methods are based on gravimetry, electric resistance, gamma attenuation, neutron humidity measurement, tensiometers and a study of the correlation between ground humidity and water evaporation. At this stage, the last technique is regarded as the most practicle method. Neutron moisture gages might be used if adhered to the regulations of NUCOR

  3. Resistorless Electronically Tunable Grounded Inductance Simulator Design

    OpenAIRE

    Herencsár, Norbert; Kartci, Aslihan

    2017-01-01

    A new realization of grounded lossless positive inductance simulator (PIS) using simple inverting voltage buffer and unity-gain current follower/inverter (CF±) is reported. Considering the input intrinsic resistance of CF± as useful active parameter, the proposed PIS can be considered as resistorless circuit and it only employs in total 16 Metal-Oxide-Semiconductor (MOS) transistors and a grounded capacitor. The resulting equivalent inductance value of the proposed simulator can be adjusted v...

  4. Single ICCII Sinusoidal Oscillators Employing Grounded Capacitors

    Directory of Open Access Journals (Sweden)

    J. W. Horng

    2011-09-01

    Full Text Available Two inverting second-generation current conveyors (ICCII based sinusoidal oscillators are presented. The first sinusoidal oscillator is composed of one ICCII, two grounded capacitors and two resistors. The oscillation condition and oscillation frequency can be orthogonally controllable. The second sinusoidal oscillator is composed of one ICCII, two grounded capacitors and three resistors. The oscillation condition and oscillation frequency can be independently controllable through different resistors.

  5. Optimizing Engineering Tools Using Modern Ground Architectures

    Science.gov (United States)

    2017-12-01

    ENGINEERING TOOLS USING MODERN GROUND ARCHITECTURES by Ryan P. McArdle December 2017 Thesis Advisor: Marc Peters Co-Advisor: I.M. Ross...Master’s thesis 4. TITLE AND SUBTITLE OPTIMIZING ENGINEERING TOOLS USING MODERN GROUND ARCHITECTURES 5. FUNDING NUMBERS 6. AUTHOR(S) Ryan P. McArdle 7... engineering tools. First, the effectiveness of MathWorks’ Parallel Computing Toolkit is assessed when performing somewhat basic computations in

  6. Search for the QCD ground state

    International Nuclear Information System (INIS)

    Reuter, M.; Wetterich, C.

    1994-05-01

    Within the Euclidean effective action approach we propose criteria for the ground state of QCD. Despite a nonvanishing field strength the ground state should be invariant with respect to modified Poincare transformations consisting of a combination of translations and rotations with suitable gauge transformations. We have found candidate states for QCD with four or more colours. The formation of gluon condensates shows similarities with the Higgs phenomenon. (orig.)

  7. Swimming literacy field hockey woman player ground.

    OpenAIRE

    Baštová, Miroslava

    2012-01-01

    Title: Swimming literacy field hockey woman player ground. Objectives: To obtain and analyze data on the level ground swimming literacy field hockey woman player. Their perception swimming literacy for life, the use of non-specific regeneration and as a training resource. Methods: Analysis of scientific literature, survey, case study, data analysis and graphical presentation of results. Results of the work: field hockey player as swimming literate, benefits swimming but not used as a means of...

  8. Shielding and grounding in large detectors

    International Nuclear Information System (INIS)

    Radeka, V.

    1998-09-01

    Prevention of electromagnetic interference (EMI), or ''noise pickup,'' is an important design aspect in large detectors in accelerator environments. Shielding effectiveness as a function of shield thickness and conductivity vs the type and frequency of the interference field is described. Noise induced in transmission lines by ground loop driven currents in the shield is evaluated and the importance of low shield resistance is emphasized. Some measures for prevention of ground loops and isolation of detector-readout systems are discussed

  9. Deflection of electron beams by ground planes

    International Nuclear Information System (INIS)

    Fernsler, R.F.; Lampe, M.

    1991-01-01

    Analytic methods are used to determine the effect of a nearby ground plane on the trajectory of a relativistic electron beam passing through dense gas. The beam is shown to respond to the ground plane in one of two distinct modes, determined by beam current and energy. Low-power beams deflect from the ground plane and tear longitudinally. High-power beams do not deflect or tear but tilt, i.e., the beam axis is no longer parallel to the direction of propagation. This conclusion is reached by computing the net beam force as a superposition of the ''bare'' ground-plane forces, the shielding forces from the beam-generated plasma, the body coupling forces induced by beam tilt, and the force that arises as the beam separates from the plasma. Effects from electromagnetic retardation and ground resistivity are shown to be negligible in typical cases of interest, and the interaction between ground planes and other external forces is discussed as well

  10. Ground-motion prediction from tremor

    Science.gov (United States)

    Baltay, Annemarie S.; Beroza, Gregory C.

    2013-01-01

    The widespread occurrence of tremor, coupled with its frequency content and location, provides an exceptional opportunity to test and improve strong ground-motion attenuation relations for subduction zones. We characterize the amplitude of thousands of individual 5 min tremor events in Cascadia during three episodic tremor and slip events to constrain the distance decay of peak ground acceleration (PGA) and peak ground velocity (PGV). We determine the anelastic attenuation parameter for ground-motion prediction equations (GMPEs) to a distance of 150 km, which is sufficient to place important constraints on ground-motion decay. Tremor PGA and PGV show a distance decay that is similar to subduction-zone-specific GMPEs developed from both data and simulations; however, the massive amount of data present in the tremor observations should allow us to refine distance-amplitude attenuation relationships for use in hazard maps, and to search for regional variations and intrasubduction zone differences in ground-motion attenuation.

  11. Grounded theory research: literature reviewing and reflexivity.

    Science.gov (United States)

    McGhee, Gerry; Marland, Glenn R; Atkinson, Jacqueline

    2007-11-01

    This paper is a report of a discussion of the arguments surrounding the role of the initial literature review in grounded theory. Researchers new to grounded theory may find themselves confused about the literature review, something we ourselves experienced, pointing to the need for clarity about use of the literature in grounded theory to help guide others about to embark on similar research journeys. The arguments for and against the use of a substantial topic-related initial literature review in a grounded theory study are discussed, giving examples from our own studies. The use of theoretically sampled literature and the necessity for reflexivity are also discussed. Reflexivity is viewed as the explicit quest to limit researcher effects on the data by awareness of self, something seen as integral both to the process of data collection and the constant comparison method essential to grounded theory. A researcher who is close to the field may already be theoretically sensitized and familiar with the literature on the study topic. Use of literature or any other preknowledge should not prevent a grounded theory arising from the inductive-deductive interplay which is at the heart of this method. Reflexivity is needed to prevent prior knowledge distorting the researcher's perceptions of the data.

  12. Ground assessment methods for nuclear power plant

    International Nuclear Information System (INIS)

    1985-01-01

    It is needless to say that nuclear power plant must be constructed on the most stable and safe ground. Reliable assessment method is required for the purpose. The Ground Integrity Sub-committee of the Committee of Civil Engineering of Nuclear Power Plant started five working groups, the purpose of which is to systematize the assessment procedures including geological survey, ground examination and construction design. The works of working groups are to establishing assessment method of activities of faults, standardizing the rock classification method, standardizing assessment and indication method of ground properties, standardizing test methods and establishing the application standard for design and construction. Flow diagrams for the procedures of geological survey, for the investigation on fault activities and ground properties of area where nuclear reactor and important outdoor equipments are scheduled to construct, were established. And further, flow diagrams for applying investigated results to design and construction of plant, and for determining procedure of liquidification nature of ground etc. were also established. These systematized and standardized methods of investigation are expected to yield reliable data for assessment of construction site of nuclear power plant and lead to the safety of construction and operation in the future. In addition, the execution of these systematized and detailed preliminary investigation for determining the construction site of nuclear power plant will make much contribution for obtaining nation-wide understanding and faith for the project. (Ishimitsu, A.)

  13. Guidelines for determining design basis ground motions

    International Nuclear Information System (INIS)

    1993-11-01

    This report develops and applies a method for estimating strong earthquake ground motion. The emphasis of this study is on ground motion estimation in Eastern North America (east of the Rocky Mountains), with particular emphasis on the Eastern United States and southeastern Canada. Specifically considered are ground motions resulting from earthquakes with magnitudes from 5 to 8, fault distances from 0 to 500 km, and frequencies from 1 to 35 Hz. The two main objectives were: (1) to develop generic relations for estimating ground motion appropriate for site screening; and (2) to develop a guideline for conducting a thorough site investigation needed to define the seismic design basis. For the first objective, an engineering model was developed to predict the expected ground motion on rock sites, with an additional set of amplification factors to account for the response of the soil column over rock at soil sites. The results incorporate best estimates of ground motion as well as the randomness and uncertainty associated with those estimates. For the second objective, guidelines were developed for gathering geotechnical information at a site and using this information in calculating site response. As a part of this development, an extensive set of geotechnical and seismic investigations was conducted at three reference sites. Together, the engineering model and guidelines provide the means to select and assess the seismic suitability of a site

  14. Jung's equation of the ground of being with the ground of psyche.

    Science.gov (United States)

    Dourley, John

    2011-09-01

    The paper amplifies Jung's psychology of ground associated with the culmination of the alchemical process in the unus mundus. It argues that Jung and Dorn identify the experience of the ground with the experience of divinity as the common originary source of individual and totality. It notes the monistic and pantheistic implications of the experience and goes on to amplify the experience through Eckhart's mediaeval mysticism of ground and Paul Tillich's modern philosophical/theological understanding of ground. It concludes that the Jung/Dorn psychological understanding of ground supersedes monotheistic consciousness. Their vision supports the emergence of a societal myth based on the identification of the ground as the source of all divinities and faith in them. This source currently urges a mythic consciousness that would surpass its past and current concretions and so alleviate the threat that monotheistic consciousness in any domain now poses to human survival. © 2011, The Society of Analytical Psychology.

  15. Proven Innovations and New Initiatives in Ground System Development: Reducing Costs in the Ground System

    Science.gov (United States)

    Gunn, Jody M.

    2006-01-01

    The state-of-the-practice for engineering and development of Ground Systems has evolved significantly over the past half decade. Missions that challenge ground system developers with significantly reduced budgets in spite of requirements for greater and previously unimagined functionality are now the norm. Making the right trades early in the mission lifecycle is one of the key factors to minimizing ground system costs. The Mission Operations Strategic Leadership Team at the Jet Propulsion Laboratory has spent the last year collecting and working through successes and failures in ground systems for application to future missions.

  16. Grounding-Induced Sectional Forces and Residual Strength of Grounded Ship Hulls

    DEFF Research Database (Denmark)

    Paik, Jeom Kee; Pedersen, Preben Terndrup

    1996-01-01

    The aim of the present study is to determine the sectional forces induced by ship grounding and also to assess the residual strength of groundedship hulls. An analytical approach is used to estimate the grounding-induced sectional forces of ships. The extent and location of structural damage due...... to grounding is defined based on the ABS Safe Hull guide. The residual strength of damaged hulls is calculated by using a simple analytical formula. The method is applied to residual strength assessment of a damaged double hull tanker of 38,400 dwt due to grounding....

  17. Grounding line processes on the Totten Glacier

    Science.gov (United States)

    Cook, S.; Watson, C. S.; Galton-Fenzi, B.; Peters, L. E.; Coleman, R.

    2017-12-01

    The Totten Glacier has been an area of recent interest due to its large drainage basin, much of which is grounded below sea level and has a history of large scale grounding line movement. Reports that warm water reaches the sub-ice shelf cavity have led to speculation that it could be vulnerable to future grounding line retreat. Over the Antarctic summer 2016/17 an array of 6 GPS and autonomous phase-sensitive radar (ApRES) units were deployed in the grounding zone of the Totten Glacier. These instruments measure changes in ice velocity and thickness which can be used to investigate both ice dynamics across the grounding line, and the interaction between ice and ocean in the subglacial cavity. Basal melt rates calculated from the ApRES units on floating ice range from 1 to 17 m/a. These values are significantly lower than previous estimates of basal melt rate produced by ocean modelling of the subglacial cavity. Meanwhile, GPS-derived velocity and elevation on the surface of the ice show a strong tidal signal, as does the vertical strain rate within the ice derived from internal layering from the ApRES instruments. These results demonstrate the significance of the complex grounding pattern of the Totten Glacier. The presence of re-grounding points has significant implications for the dynamics of the glacier and the ocean circulation within the subglacial cavity. We discuss what can be learned from our in situ measurements, and how they can be used to improve models of the glacier's future behaviour.

  18. TNX Burying Ground: Environmental information document

    International Nuclear Information System (INIS)

    Dunaway, J.K.W.; Johnson, W.F.; Kingley, L.E.; Simmons, R.V.; Bledsoe, H.W.

    1987-03-01

    The TNX Burying Ground, located within the TNX Area of the Savannah River Plant (SRP), was originally built to dispose of debris from an experimental evaporator explosion at TNX in 1953. This evaporator contained approximately 590 kg of uranyl nitrate. From 1980 to 1984, much of the waste material buried at TNX was excavated and sent to the SRP Radioactive Waste Burial Grounds for reburial. An estimated 27 kg of uranyl nitrate remains buried at TNX. The TNX Burying Ground consists of three sites known to contain waste and one site suspected of containing waste material. All four sites are located within the TNX security fenceline. Groundwater at the TNX Burying Ground was not evaluated because there are no groundwater monitoring wells installed in the immediate vicinity of this waste site. The closure options considered for the TNX Burying Ground are waste removal and closure, no waste removal and closure, and no action. The predominant pathways for human exposure to chemical and/or radioactive constituents are through surface, subsurface, and atmospheric transport. Modeling calculations were made to determine the risks to human population via these general pathways for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated

  19. Longevity of Emplacement Drift Ground Support Materials

    International Nuclear Information System (INIS)

    Tang, D.

    2000-01-01

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for selection of materials for ground support that will function throughout the preclosure period. The Development Plan (DP) for this analysis is given in CRWMS M and O (Civilian Radioactive Waste Management System Management and Operating Contractor) (1999a). The candidate materials for ground support are steel (carbon steel, ductile cast iron, galvanized steel, and stainless steel, etc.) and cement. Steel will mainly be used for steel sets, lagging, channels, rock bolts, and wire mesh. Cement usage is only considered in the case of grouted rock bolts. The candidate materials for the invert structure are steel and crushed rock ballast. The materials shall be evaluated for the repository emplacement drift environment under a specific thermal loading condition based on the proposed License Application Design Selection (LADS) design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground control materials for use in emplacement drifts. (2) Review existing documents concerning behavior of candidate ground control materials during the preclosure period. The major criteria to be considered for steel are mechanical and thermal properties, and durability, of which corrosion is the most important concern. (3) Evaluate the available results and develop recommendations for material(s) to be used

  20. XML Flight/Ground Data Dictionary Management

    Science.gov (United States)

    Wright, Jesse; Wiklow, Colette

    2007-01-01

    A computer program generates Extensible Markup Language (XML) files that effect coupling between the command- and telemetry-handling software running aboard a spacecraft and the corresponding software running in ground support systems. The XML files are produced by use of information from the flight software and from flight-system engineering. The XML files are converted to legacy ground-system data formats for command and telemetry, transformed into Web-based and printed documentation, and used in developing new ground-system data-handling software. Previously, the information about telemetry and command was scattered in various paper documents that were not synchronized. The process of searching and reading the documents was time-consuming and introduced errors. In contrast, the XML files contain all of the information in one place. XML structures can evolve in such a manner as to enable the addition, to the XML files, of the metadata necessary to track the changes and the associated documentation. The use of this software has reduced the extent of manual operations in developing a ground data system, thereby saving considerable time and removing errors that previously arose in the translation and transcription of software information from the flight to the ground system.

  1. Demystifying Theoretical Sampling in Grounded Theory Research

    Directory of Open Access Journals (Sweden)

    Jenna Breckenridge BSc(Hons,Ph.D.Candidate

    2009-06-01

    Full Text Available Theoretical sampling is a central tenet of classic grounded theory and is essential to the development and refinement of a theory that is ‘grounded’ in data. While many authors appear to share concurrent definitions of theoretical sampling, the ways in which the process is actually executed remain largely elusive and inconsistent. As such, employing and describing the theoretical sampling process can present a particular challenge to novice researchers embarking upon their first grounded theory study. This article has been written in response to the challenges faced by the first author whilst writing a grounded theory proposal. It is intended to clarify theoretical sampling for new grounded theory researchers, offering some insight into the practicalities of selecting and employing a theoretical sampling strategy. It demonstrates that the credibility of a theory cannot be dissociated from the process by which it has been generated and seeks to encourage and challenge researchers to approach theoretical sampling in a way that is apposite to the core principles of the classic grounded theory methodology.

  2. Advanced Testing Method for Ground Thermal Conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaobing [ORNL; Clemenzi, Rick [Geothermal Design Center Inc.; Liu, Su [University of Tennessee (UT)

    2017-04-01

    A new method is developed that can quickly and more accurately determine the effective ground thermal conductivity (GTC) based on thermal response test (TRT) results. Ground thermal conductivity is an important parameter for sizing ground heat exchangers (GHEXs) used by geothermal heat pump systems. The conventional GTC test method usually requires a TRT for 48 hours with a very stable electric power supply throughout the entire test. In contrast, the new method reduces the required test time by 40%–60% or more, and it can determine GTC even with an unstable or intermittent power supply. Consequently, it can significantly reduce the cost of GTC testing and increase its use, which will enable optimal design of geothermal heat pump systems. Further, this new method provides more information about the thermal properties of the GHEX and the ground than previous techniques. It can verify the installation quality of GHEXs and has the potential, if developed, to characterize the heterogeneous thermal properties of the ground formation surrounding the GHEXs.

  3. Renal Mitochondrial Response to Low Temperature in Non-Hibernating and Hibernating Species

    NARCIS (Netherlands)

    Dugbartey, George J; Hardenberg, Maarten C; Kok, Wendelinde F; Boerema, Ate S; Carey, Hannah V; Staples, James F; Henning, Robert H; Bouma, Hjalmar R

    2017-01-01

    SIGNIFICANCE: Therapeutic hypothermia is commonly applied to limit ischemic injury in organ transplantation, during cardiac and brain surgery and after cardiopulmonary resuscitation. In these procedures, the kidneys are particularly at risk for ischemia/reperfusion injury (IRI), likely due to their

  4. Soil and ground-water remediation techniques

    International Nuclear Information System (INIS)

    Beck, P.

    1996-01-01

    Urban areas typically contain numerous sites underlain by soils or ground waters which are contaminated to levels that exceed clean-up guidelines and are hazardous to public health. Contamination most commonly results from the disposal, careless use and spillage of chemicals, or the historic importation of contaminated fill onto properties undergoing redevelopment. Contaminants of concern in soil and ground water include: inorganic chemicals such as heavy metals; radioactive metals; salt and inorganic pesticides, and a range of organic chemicals included within petroleum fuels, coal tar products, PCB oils, chlorinated solvents, and pesticides. Dealing with contaminated sites is a major problem affecting all urban areas and a wide range of different remedial technologies are available. This chapter reviews the more commonly used methods for ground-water and soil remediation, paying particular regard to efficiency and applicability of specific treatments to different site conditions. (author). 43 refs., 1 tab., 27 figs

  5. Strong ground motion prediction using virtual earthquakes.

    Science.gov (United States)

    Denolle, M A; Dunham, E M; Prieto, G A; Beroza, G C

    2014-01-24

    Sedimentary basins increase the damaging effects of earthquakes by trapping and amplifying seismic waves. Simulations of seismic wave propagation in sedimentary basins capture this effect; however, there exists no method to validate these results for earthquakes that have not yet occurred. We present a new approach for ground motion prediction that uses the ambient seismic field. We apply our method to a suite of magnitude 7 scenario earthquakes on the southern San Andreas fault and compare our ground motion predictions with simulations. Both methods find strong amplification and coupling of source and structure effects, but they predict substantially different shaking patterns across the Los Angeles Basin. The virtual earthquake approach provides a new approach for predicting long-period strong ground motion.

  6. Shallow ground disposal of radioactive wastes

    International Nuclear Information System (INIS)

    1981-01-01

    This guidebook outlines the factors to be considered in site selection, design, operation, shut-down and surveillance as well as the regulatory requirements of repositories for safe disposal of radioactive waste in shallow ground. No attempt is made to summarize the existing voluminous literature on the many facets of radioactive waste disposal. In the context of this guidebook, shallow ground disposal refers to the emplacement of radioactive waste, with or without engineered barriers, above or below the ground surface, where the final protective covering is of the order of a few metres thick. Deep geological disposal and other underground disposal methods, management of mill tailings and disposal into the sea have been or will be considered in other IAEA publications. These guidelines have been made sufficiently general to cover a broad variety of climatic, hydrogeological and biological conditions. They may need to be interpreted or modified to reflect local conditions and national regulations

  7. FEBEX bentonite colloid stability in ground water

    Energy Technology Data Exchange (ETDEWEB)

    Seher, H.; Schaefer, T.; Geckeis, H. [Inst. fuer Nukleare Entsorgung (INE), Forschungszentrum Karlsruhe, 76021 Karlsruhe (Germany)]. e-mail: holger.seher@ine.fzk .de; Fanghaenel, T. [Ruprecht-Karls-Univ. Heidelberg, Physikalisch-Chemisches In st., D-69120 Heidelberg (Germany)

    2007-06-15

    Coagulation experiments are accomplished to identify the geochemical conditions for the stability of Febex bentonite colloids in granite ground water. The experiments are carried out by varying pH, ionic strength and type of electrolyte. The dynamic light scattering technique (photon correlation spectroscopy) is used to measure the size evolution of the colloids with time. Agglomeration rates are higher in MgCl{sub 2} and CaCl{sub 2} than in NaCl solution. Relative agglomeration rates follow approximately the Schulze-Hardy rule. Increasing agglomeration rates at pH>8 are observed in experiments with MgCl{sub 2} and CaCl{sub 2} which are, however, caused by coprecipitation phenomena. Bentonite colloid stability fields derived from the colloid agglomeration experiments predict low colloid stabilization in granite ground water taken from Aespoe, Sweden, and relatively high colloid stability in Grimsel ground water (Switzerland)

  8. Heat pipes for ground heating and cooling

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, L L

    1988-01-01

    Different versions of heat pipe ground heating and cooling devices are considered. Solar energy, biomass, ground stored energy, recovered heat of industrial enterprises and ambient cold air are used as energy and cold sources. Heat pipe utilization of air in winter makes it possible to design accumulators of cold and ensures deep freezing of ground in order to increase its mechanical strength when building roadways through the swamps and ponds in Siberia. Long-term underground heat storage systems are considered, in which the solar and biomass energy is accumulated and then transferred to heat dwellings and greenhouses, as well as to remove snow from roadways with the help of heat pipes and solar collectors.

  9. Ground beetles of the Ukraine (Coleoptera, Carabidae).

    Science.gov (United States)

    Putchkov, Alexander

    2011-01-01

    A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species) of the lowlands of southern Ukraine (sandy biotopes), situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed.

  10. Ground beetles of the Ukraine (Coleoptera, Carabidae

    Directory of Open Access Journals (Sweden)

    Alexander Putchkov

    2011-05-01

    Full Text Available A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species of the lowlands of southern Ukraine (sandy biotopes, situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed.

  11. Modelling man-made ground to link the above- and below- ground urban domains

    NARCIS (Netherlands)

    Schokker, J.

    2017-01-01

    This report describes the results of STSM TU1206-36204. During a visit to GEUS (DK) between 23 and 27 January 2017, Jeroen Schokker (TNO-GSN, NL) has focussed on the modelling of man-made ground as a linking pin between the above- and below-ground urban domains. Key results include: • Man-made

  12. Integration of a satellite ground support system based on analysis of the satellite ground support domain

    Science.gov (United States)

    Pendley, R. D.; Scheidker, E. J.; Levitt, D. S.; Myers, C. R.; Werking, R. D.

    1994-11-01

    This analysis defines a complete set of ground support functions based on those practiced in real space flight operations during the on-orbit phase of a mission. These functions are mapped against ground support functions currently in use by NASA and DOD. Software components to provide these functions can be hosted on RISC-based work stations and integrated to provide a modular, integrated ground support system. Such modular systems can be configured to provide as much ground support functionality as desired. This approach to ground systems has been widely proposed and prototyped both by government institutions and commercial vendors. The combined set of ground support functions we describe can be used as a standard to evaluate candidate ground systems. This approach has also been used to develop a prototype of a modular, loosely-integrated ground support system, which is discussed briefly. A crucial benefit to a potential user is that all the components are flight-qualified, thus giving high confidence in their accuracy and reliability.

  13. Illumination compensation in ground based hyperspectral imaging

    Science.gov (United States)

    Wendel, Alexander; Underwood, James

    2017-07-01

    Hyperspectral imaging has emerged as an important tool for analysing vegetation data in agricultural applications. Recently, low altitude and ground based hyperspectral imaging solutions have come to the fore, providing very high resolution data for mapping and studying large areas of crops in detail. However, these platforms introduce a unique set of challenges that need to be overcome to ensure consistent, accurate and timely acquisition of data. One particular problem is dealing with changes in environmental illumination while operating with natural light under cloud cover, which can have considerable effects on spectral shape. In the past this has been commonly achieved by imaging known reference targets at the time of data acquisition, direct measurement of irradiance, or atmospheric modelling. While capturing a reference panel continuously or very frequently allows accurate compensation for illumination changes, this is often not practical with ground based platforms, and impossible in aerial applications. This paper examines the use of an autonomous unmanned ground vehicle (UGV) to gather high resolution hyperspectral imaging data of crops under natural illumination. A process of illumination compensation is performed to extract the inherent reflectance properties of the crops, despite variable illumination. This work adapts a previously developed subspace model approach to reflectance and illumination recovery. Though tested on a ground vehicle in this paper, it is applicable to low altitude unmanned aerial hyperspectral imagery also. The method uses occasional observations of reference panel training data from within the same or other datasets, which enables a practical field protocol that minimises in-field manual labour. This paper tests the new approach, comparing it against traditional methods. Several illumination compensation protocols for high volume ground based data collection are presented based on the results. The findings in this paper are

  14. Water budget for SRP burial ground area

    International Nuclear Information System (INIS)

    Hubbard, J.E.; Emslie, R.H.

    1984-01-01

    Radionuclide migration from the SRP burial ground for solid low-level waste has been studied extensively. Most of the buried radionuclides are fixed on the soil and show negligible movement. The major exception is tritium, which when leached from the waste by percolating rainfall, forms tritiated water and moves with the groundwater. The presence of tritium has been useful in tracing groundwater flow paths to outcrop. A subsurface tritium plume moving from the southwest corner of the burial ground toward an outcrop near Four Mile Creek has been defined. Groundwater movement is so slow that much of the tritium decays before reaching the outcrop. The burial ground tritium plume defined to date is virtually all in the uppermost sediment layer, the Barnwell Formation. The purpose of the study reported in this memorandum was to investigate the hypothesis that deeper flow paths, capable of carrying substantial amounts of tritium, may exist in the vicinity of the burial ground. As a first step in seeking deeper flow paths, a water budget was constructed for the burial ground site. The water budget, a materials balance used by hydrologists, is expressed in annual area inches of rainfall. Components of the water budget for the burial ground area were analyzed to determine whether significant flow paths may exist below the tan clay. Mean annual precipitation was estimated as 47 inches, with evapotranspiration, run-off, and groundwater recharge estimated as 30, 2, and 15 inches, respectively. These estimates, when combined with groundwater discharge data, suggest that 5 inches of the groundwater recharge flow above the tan clay and that 10 inches flow below the tan clay. Therefore, two-thirds of the groundwater recharge appears to follow flow paths that are deeper than those previously found. 13 references, 10 figures, 5 tables

  15. Management Research and Grounded Theory: A review of grounded theorybuilding approach in organisational and management research.

    Directory of Open Access Journals (Sweden)

    Graham J.J. Kenealy, Ph.D.

    2008-06-01

    Full Text Available Grounded theory is a systematic methodology for the collection and analysis of data which was discovered by Glaser and Strauss in the 1960’s. The discovery of this method was first presented to the academic community in their book ‘The Discovery of Grounded Theory’ (1967 which still remains a primary point of reference for those undertaking qualitative research and grounded theory in particular. This powerful research method has become very popular in some research domains; whilst increasing in popularity it is still less prevalent in the field of organisational and management research particularly in its original form. This self reflexive paper sets out to explore the possibilities for this imbalance which takes the discussion onto the areas of methodological adaptation and training. It also enters the debate about access to research subjects and provides a succinct argument supporting the notion that grounded theory should simply be viewed as a method that develops empirically grounded conceptual theory.

  16. A Mixed Prediction Model of Ground Subsidence for Civil Infrastructures on Soft Ground

    Directory of Open Access Journals (Sweden)

    Kiyoshi Kobayashi

    2012-01-01

    Full Text Available The estimation of ground subsidence processes is an important subject for the asset management of civil infrastructures on soft ground, such as airport facilities. In the planning and design stage, there exist many uncertainties in geotechnical conditions, and it is impossible to estimate the ground subsidence process by deterministic methods. In this paper, the sets of sample paths designating ground subsidence processes are generated by use of a one-dimensional consolidation model incorporating inhomogeneous ground subsidence. Given the sample paths, the mixed subsidence model is presented to describe the probabilistic structure behind the sample paths. The mixed model can be updated by the Bayesian methods based upon the newly obtained monitoring data. Concretely speaking, in order to estimate the updating models, Markov Chain Monte Calro method, which is the frontier technique in Bayesian statistics, is applied. Through a case study, this paper discussed the applicability of the proposed method and illustrated its possible application and future works.

  17. Ground-atmosphere interactions at Gale

    Science.gov (United States)

    Renno, N. O.; Martinez, G.; Ramos, M.; Hallet, B.; Gómez, F. G.; Jun, I.; Fisk, M. R.; Gomez-Elvira, J.; Hamilton, V. E.; Mischna, M. A.; Sletten, R. S.; Martin-Torres, J.; De La Torre Juarez, M.; Vasavada, A. R.; Zorzano, M.

    2013-12-01

    We analyze variations in environmental parameters and regolith properties along Curiosity's track to determine the possible causes of an abrupt change in the thermal properties of the ground and the atmosphere observed around Sol 120, as the rover transitioned from an area of sandy soil (Rocknest) to an area of fractured bedrock terrain (Yellowknife). Curiosity is instrumented with the Rover Environmental Monitoring Station (REMS) and the Dynamic Albedo of Neutrons (DAN) sensors to measure the air temperature, the ground temperature, and the hydrogen content of the shallow subsurface along Curiosity's track. Analysis of the REMS data is used to estimate the regolith's heat budget. This analysis suggests that the abrupt decrease in the ground and atmosphere temperature and the difference between ground and air temperatures observed around Sol 120 is likely caused by an increase in the soil thermal inertia. The changes in thermal inertia have been known for some time so confirming this by the REMS package provides ground truthing. A new unexpected finding is that the regolith water content, as indicated by DAN's detection of hydrogen content, is higher in the Yellowknife soil. Another interesting finding at this site are the holes and other signs of recent geological activity in the area of fractured terrain that may reflect large volumetric variations and facilitate gas exchange between the ground and atmosphere. Near-surface volumetric changes in soil and bedrock could reflect changes in the volume of subsurface H2O, or in the partitioning of H2O among its three phases. Volume increases could also result from salt crystal growth in rock pores and soil pores associated with the adsorption of water vapor. Crystallization in pores is a significant weathering process on Earth; it could well be active on Mars. Salts also inhibits the exchange of moisture between the ground and the atmosphere, and cements the soils of arid places such as in the McMurdo Dry Valleys in

  18. Ground Control for Emplacement Drifts for SR

    International Nuclear Information System (INIS)

    Y. Sun

    2000-01-01

    This analysis demonstrates that a satisfactory ground control system can be designed for the Yucca Mountain site, and provides the technical basis for the design of ground support systems to be used in repository emplacement and non-emplacement drifts. The repository ground support design was based on analytical methods using acquired computer codes, and focused on the final support systems. A literature review of case histories, including the lessons learned from the design and construction of the ESF, the studies on the seismic damages of underground openings, and the use of rock mass classification systems in the ground support design, was conducted (Sections 6.3.4 and 6.4). This review provided some basis for determining the inputs and methodologies used in this analysis. Stability of the supported and unsupported emplacement and non-emplacement drifts was evaluated in this analysis. The excavation effects (i.e., state of the stress change due to excavation), thermal effects (i.e., due to heat output from waste packages), and seismic effects (i.e., from potential earthquake events) were evaluated, and stress controlled modes of failure were examined for two in situ stress conditions (k 0 =0.3 and 1.0) using rock properties representing rock mass categories of 1 and 5. Variation of rock mass units such as the non-lithophysal (Tptpmn) and lithophysal (Tptpll) was considered in the analysis. The focus was on the non-lithophysal unit because this unit appears to be relatively weaker and has much smaller joint spacing. Therefore, the drift stability and ground support needs were considered to be controlled by the design for this rock unit. The ground support systems for both emplacement and non-emplacement drifts were incorporated into the models to assess their performance under in situ, thermal, and seismic loading conditions. Both continuum and discontinuum modeling approaches were employed in the analyses of the rock mass behavior and in the evaluation of the

  19. Process for storing radioactive waste in ground

    International Nuclear Information System (INIS)

    Cohen, P.; Gouvenot, D.; Pagny, P.

    1983-01-01

    A process for storing radioactive waste in a cavity in the ground is claimed. The waste is conditioned and isolated from the ground by at least one retention barrier. A grout consisting of 1000 parts by weight of water, 40 to 400 parts by weight of cement, 80 to 1000 parts by weight of at least one clay chosen from the group including montmorillonite, illite and vermiculite, as well as 25 to 1200 parts by weight of kieselguhr and/or natural or artificial pozzuolanas is introduced into gaps in the soil areas surrounding the cavity

  20. Nitrate Removal from Ground Water: A Review

    Directory of Open Access Journals (Sweden)

    Archna

    2012-01-01

    Full Text Available Nitrate contamination of ground water resources has increased in Asia, Europe, United States, and various other parts of the world. This trend has raised concern as nitrates cause methemoglobinemia and cancer. Several treatment processes can remove nitrates from water with varying degrees of efficiency, cost, and ease of operation. Available technical data, experience, and economics indicate that biological denitrification is more acceptable for nitrate removal than reverse osmosis and ion exchange. This paper reviews the developments in the field of nitrate removal processes which can be effectively used for denitrifying ground water as well as industrial water.

  1. Radioactive waste disposal into the ground

    International Nuclear Information System (INIS)

    1965-01-01

    Disposal into ground has sometimes proved to be an expedient and simple method. Where ground disposal has become an established practice, the sites have so far been limited to those remote from population centres; but in other respects, such as in climate and soil conditions, their characteristics vary widely. Experience gained at these sites has illustrated the variety of problems in radioactive waste migration and the resulting pollution and environmental radiation levels that may reasonably be anticipated at other sites, whether remote from population centres or otherwise.

  2. Creating Space Plasma from the Ground

    Science.gov (United States)

    2016-05-12

    AFRL-AFOSR-VA-TR-2016-0179 CREATING SPACE PLASMA FROM THE GROUND Herbert C Carlson UTAH STATE UNIVERSITY Final Report 05/12/2016 DISTRIBUTION A...DATE (DD-MM-YYYY) 05/14/2016 2. REPORT TYPE Final 3. DATES COVERED (From - To) 08/14/2012-05/14/2016 4. TITLE AND SUBTITLE Creating space plasma from...Report (2016) Creating Space Plasma from the Ground Grant FA9550-11-1-0236 AFOSR Program Manager Dr. Kent Miller PI: Herbert C. Carlson Center for

  3. Prospects of protected ground in Russia

    Directory of Open Access Journals (Sweden)

    M. I. Mamedov

    2014-01-01

    Full Text Available The article analyzes the current state and prospects of  protected  ground development in the Russian Federation based on the data of the Ministry  of Agriculture and  the Federal State Statistics Service. The indexes of production of vegetable crops in different regions of the  Russian Federation are given. The problems, which  are  holding back the greenhouse business, are  discussed. The possibilities of increasing the  area of protected ground and vegetable production are shown.

  4. Eliciting Perceptual Ground Truth for Image Segmentation

    OpenAIRE

    Hodge, Victoria Jane; Eakins, John; Austin, Jim

    2006-01-01

    In this paper, we investigate human visual perception and establish a body of ground truth data elicited from human visual studies. We aim to build on the formative work of Ren, Eakins and Briggs who produced an initial ground truth database. Human subjects were asked to draw and rank their perceptions of the parts of a series of figurative images. These rankings were then used to score the perceptions, identify the preferred human breakdowns and thus allow us to induce perceptual rules for h...

  5. Geotechnics - the key to ground water protection

    DEFF Research Database (Denmark)

    Baumann, Jens; Foged, Niels; Jørgensen, Peter

    2000-01-01

    During the past 5 to 10 years research into ground water protection has proved that fractures in clay till may increase the hydraulic conductivity and herby the vulnerability of the ground water considerably. However, research has not identified a non-expensive and efficient method to map...... the fracture conditions of the various clay tills. Tests performed at the Danish Geotechnical Institute with large undisturbed columns of clay till show that there is a relation between the strength of the clay till and the hydraulic conductivity. Geotechnical methods may therefore be the key to determine...

  6. PV Systems Reliability Final Technical Report: Ground Fault Detection

    Energy Technology Data Exchange (ETDEWEB)

    Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    We have examined ground faults in PhotoVoltaic (PV) arrays and the efficacy of fuse, current detection (RCD), current sense monitoring/relays (CSM), isolation/insulation (Riso) monitoring, and Ground Fault Detection and Isolation (GFID) using simulations based on a Simulation Program with Integrated Circuit Emphasis SPICE ground fault circuit model, experimental ground faults installed on real arrays, and theoretical equations.

  7. Investigation of the relationship between ground and engineering ...

    Indian Academy of Sciences (India)

    In order to investigate possible ground motion amplification in earthquake resistant building design, relationship between the ground and engineering bedrock must be ensured. In order to provide this relation, structure, basic characteristics, and thickness of the ground are investigated. In this context, calculating ground ...

  8. [Review of digital ground object spectral library].

    Science.gov (United States)

    Zhou, Xiao-Hu; Zhou, Ding-Wu

    2009-06-01

    A higher spectral resolution is the main direction of developing remote sensing technology, and it is quite important to set up the digital ground object reflectance spectral database library, one of fundamental research fields in remote sensing application. Remote sensing application has been increasingly relying on ground object spectral characteristics, and quantitative analysis has been developed to a new stage. The present article summarized and systematically introduced the research status quo and development trend of digital ground object reflectance spectral libraries at home and in the world in recent years. Introducing the spectral libraries has been established, including desertification spectral database library, plants spectral database library, geological spectral database library, soil spectral database library, minerals spectral database library, cloud spectral database library, snow spectral database library, the atmosphere spectral database library, rocks spectral database library, water spectral database library, meteorites spectral database library, moon rock spectral database library, and man-made materials spectral database library, mixture spectral database library, volatile compounds spectral database library, and liquids spectral database library. In the process of establishing spectral database libraries, there have been some problems, such as the lack of uniform national spectral database standard and uniform standards for the ground object features as well as the comparability between different databases. In addition, data sharing mechanism can not be carried out, etc. This article also put forward some suggestions on those problems.

  9. Tree root mapping with ground penetrating radar

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2009-09-01

    Full Text Available In this paper, the application of ground penetrating radar (GPR) for the mapping of near surface tree roots is demonstrated. GPR enables tree roots to be mapped in a non-destructive and cost-effective manner and is therefore a useful prospecting...

  10. Photovoltaic module mounting clip with integral grounding

    Science.gov (United States)

    Lenox, Carl J.

    2010-08-24

    An electrically conductive mounting/grounding clip, usable with a photovoltaic (PV) assembly of the type having an electrically conductive frame, comprises an electrically conductive body. The body has a central portion and first and second spaced-apart arms extending from the central portion. Each arm has first and second outer portions with frame surface-disrupting element at the outer portions.

  11. Planning School Grounds for Outdoor Learning

    Science.gov (United States)

    Wagner, Cheryl; Gordon, Douglas

    2010-01-01

    This publication covers the planning and design of school grounds for outdoor learning in new and existing K-12 facilities. Curriculum development as well as athletic field planning and maintenance are not covered although some references on these topics are provided. It discusses the different types of outdoor learning environments that can be…

  12. Probability of Grounding and Collision Events

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    To quantify the risks involved in ship traffic, rational criteria for collision and grounding accidents are developed. This implies that probabilities as well as inherent consequences can be analysed and assessed. The presnt paper outlines a method for evaluation of the probability of ship...

  13. Probability of Grounding and Collision Events

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    To quantify the risks involved in ship traffic, rational criteria for collision and grounding accidents have to be developed. This implies that probabilities as well as inherent consequences have to be analyzed and assessed.The present notes outline a method for evaluation of the probability...

  14. NITRATE CONTAMINATION OF GROUND WATER (GW-761)

    Science.gov (United States)

    The occurrence of nitrate and related compounds in ground water is discussed from the perspectives of its natural as well as anthropogenic origins. A brief explanation of the nitrogen cycle touches on the production as well as utilization of ammonia, nitrite, nitrate, and nitrog...

  15. Dynasting Theory: Lessons in learning grounded theory

    Directory of Open Access Journals (Sweden)

    Johnben Teik-Cheok Loy, MBA, MTS, Ph.D.

    2011-06-01

    Full Text Available This article captures the key learning lessons gleaned from the author’s experience learning and developing a grounded theory for his doctoral dissertation using the classic methodology as conceived by Barney Glaser. The theory was developed through data gathered on founders and successors of Malaysian Chinese family-own businesses. The main concern for Malaysian Chinese family businesses emerged as dynasting . the building, maintaining, and growing the power and resources of the business within the family lineage. The core category emerged as dynasting across cultures, where founders and successors struggle to transition from traditional Chinese to hybrid cultural and modernized forms of family business from one generation to the next. The key learning lessons were categorized under five headings: (a sorting through different versions of grounded theory, (b educating and managing research stakeholders, (c embracing experiential learning, (d discovering the core category: grounded intuition, and (e recognizing limitations and possibilities.Keywords: grounded theory, learning, dynasting, family business, Chinese

  16. Ground water work breakdown structure dictionary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support.

  17. CENTRAL NIGERIA: DEDUCTIONS FROM GROUND MAGNETIC

    African Journals Online (AJOL)

    Magnetic field data of the K uri River basin were obtained from a ground magnetic survey using an MP-2 proton ... These shapes conform to the concept of the ... Granite Complex in the South west (Fig. 1). ..... Cross-section: It's Properties and.

  18. Ground water work breakdown structure dictionary

    International Nuclear Information System (INIS)

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support

  19. GRACAT, Software for grounding and collision analysis

    DEFF Research Database (Denmark)

    Friis-Hansen, Peter; Simonsen, Bo Cerup

    2002-01-01

    and grounding accidents. The software consists of three basic analysis modules and one risk mitigation module: 1) frequency, 2) damage, and 3) consequence. These modules can be used individually or in series and the analyses can be performed in deterministic or probabilistic mode. Finally, in the mitigation...

  20. Ground Robotics Capabilities Conference and Exhibition

    Science.gov (United States)

    2008-03-06

    SALON A... SALON B SALON C C O R R ID O R CROCKETT A CROCKETT B CROCKETT C CROCKETT D CROCKETT E CROCKETT F CROCKETT G CROCKETT H CROCKETT I ENTRANCE 2008 Ground...analysis for “ game changing” robotic technologies – “UGVs are significantly more complicated than UAVs, and will require much more

  1. Cavity optomechanics -- beyond the ground state

    Science.gov (United States)

    Meystre, Pierre

    2011-05-01

    The coupling of coherent optical systems to micromechanical devices, combined with breakthroughs in nanofabrication and in ultracold science, has opened up the exciting new field of cavity optomechanics. Cooling of the vibrational motion of a broad range on oscillating cantilevers and mirrors near their ground state has been demonstrated, and the ground state of at least one such system has now been reached. Cavity optomechanics offers much promise in addressing fundamental physics questions and in applications such as the detection of feeble forces and fields, or the coherent control of AMO systems and of nanoscale electromechanical devices. However, these applications require taking cavity optomechanics ``beyond the ground state.'' This includes the generation and detection of squeezed and other non-classical states, the transfer of squeezing between electromagnetic fields and motional quadratures, and the development of measurement schemes for the characterization of nanomechanical structures. The talk will present recent ``beyond ground state'' developments in cavity optomechanics. We will show how the magnetic coupling between a mechanical membrane and a BEC - or between a mechanical tuning fork and a nanoscale cantilever - permits to control and monitor the center-of-mass position of the mechanical system, and will comment on the measurement back-action on the membrane motion. We will also discuss of state transfer between optical and microwave fields and micromechanical devices. Work done in collaboration with Dan Goldbaum, Greg Phelps, Keith Schwab, Swati Singh, Steve Steinke, Mehmet Tesgin, and Mukund Vengallatore and supported by ARO, DARPA, NSF, and ONR.

  2. Purely temporal figure-ground segregation.

    Science.gov (United States)

    Kandil, F I; Fahle, M

    2001-05-01

    Visual figure-ground segregation is achieved by exploiting differences in features such as luminance, colour, motion or presentation time between a figure and its surround. Here we determine the shortest delay times required for figure-ground segregation based on purely temporal features. Previous studies usually employed stimulus onset asynchronies between figure- and ground-containing possible artefacts based on apparent motion cues or on luminance differences. Our stimuli systematically avoid these artefacts by constantly showing 20 x 20 'colons' that flip by 90 degrees around their midpoints at constant time intervals. Colons constituting the background flip in-phase whereas those constituting the target flip with a phase delay. We tested the impact of frequency modulation and phase reduction on target detection. Younger subjects performed well above chance even at temporal delays as short as 13 ms, whilst older subjects required up to three times longer delays in some conditions. Figure-ground segregation can rely on purely temporal delays down to around 10 ms even in the absence of luminance and motion artefacts, indicating a temporal precision of cortical information processing almost an order of magnitude lower than the one required for some models of feature binding in the visual cortex [e.g. Singer, W. (1999), Curr. Opin. Neurobiol., 9, 189-194]. Hence, in our experiment, observers are unable to use temporal stimulus features with the precision required for these models.

  3. Introducing Grounded Theory into translation studies | Wehrmeyer ...

    African Journals Online (AJOL)

    This article introduces tenets of Grounded Theory into a reception-oriented model for translation studies, in which the basis of comparison (tertium comparationis) between source and target texts is constructed from target audience expectancy norms. The model is primarily designed for projects where conformity to target ...

  4. Satellite-to-ground radiowave propagation

    CERN Document Server

    Allnutt, JE

    2011-01-01

    This book is a follow up to the award winning first edition and is written as a comprehensive guide for those who need to obtain a working knowledge of radiowave propagation on satellite-to-ground links at frequencies above 1 GHz, and as a reference book for experts in the field.

  5. Hypersonic Inflatable Aerodynamic Decelerator Ground Test Development

    Science.gov (United States)

    Del Corso, Jospeh A.; Hughes, Stephen; Cheatwood, Neil; Johnson, Keith; Calomino, Anthony

    2015-01-01

    Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology readiness levels have been incrementally matured by NASA over the last thirteen years, with most recent support from NASA's Space Technology Mission Directorate (STMD) Game Changing Development Program (GCDP). Recently STMD GCDP has authorized funding and support through fiscal year 2015 (FY15) for continued HIAD ground developments which support a Mars Entry, Descent, and Landing (EDL) study. The Mars study will assess the viability of various EDL architectures to enable a Mars human architecture pathfinder mission planned for mid-2020. At its conclusion in November 2014, NASA's first HIAD ground development effort had demonstrated success with fabricating a 50 W/cm2 modular thermal protection system, a 400 C capable inflatable structure, a 10-meter scale aeroshell manufacturing capability, together with calibrated thermal and structural models. Despite the unquestionable success of the first HIAD ground development effort, it was recognized that additional investment was needed in order to realize the full potential of the HIAD technology capability to enable future flight opportunities. The second HIAD ground development effort will focus on extending performance capability in key technology areas that include thermal protection system, lifting-body structures, inflation systems, flight control, stage transitions, and 15-meter aeroshell scalability. This paper presents an overview of the accomplishments under the baseline HIAD development effort and current plans for a follow-on development effort focused on extending those critical technologies needed to enable a Mars Pathfinder mission.

  6. Developing a Leadership Identity: A Grounded Theory

    Science.gov (United States)

    Komives, Susan R.; Owen, Julie E; Longerbeam, Susan D.; Mainella, Felicia C.; Osteen, Laura

    2005-01-01

    This grounded theory study on developing a leadership identity revealed a 6-stage developmental process. The thirteen diverse students in this study described their leadership identity as moving from a leader-centric view to one that embraced leadership as a collaborative, relational process. Developing a leadership identity was connected to the…

  7. Calibration of Ground -based Lidar instrument

    DEFF Research Database (Denmark)

    Villanueva, Héctor; Yordanova, Ginka

    This report presents the result of the lidar calibration performed for the given Ground-based Lidar at DTU’s test site for large wind turbines at Høvsøre, Denmark. Calibration is here understood as the establishment of a relation between the reference wind speed measurements with measurement...

  8. Thermodynamic Ground States of Complex Oxide Heterointerfaces

    DEFF Research Database (Denmark)

    Gunkel, F.; Hoffmann-Eifert, S.; Heinen, R. A.

    2017-01-01

    The formation mechanism of 2-dimensional electron gases (2DEGs) at heterointerfaces between nominally insulating oxides is addressed with a thermodynamical approach. We provide a comprehensive analysis of the thermodynamic ground states of various 2DEG systems directly probed in high temperature...

  9. Applying Modeling Tools to Ground System Procedures

    Science.gov (United States)

    Di Pasquale, Peter

    2012-01-01

    As part of a long-term effort to revitalize the Ground Systems (GS) Engineering Section practices, Systems Modeling Language (SysML) and Business Process Model and Notation (BPMN) have been used to model existing GS products and the procedures GS engineers use to produce them.

  10. Ground beetle populations near a kraft mill

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, R.; Hastings, L.; Mercer, W.R.; Smith, A.

    1973-02-01

    Twenty species of ground beetles (Family Carabidae) and one species of carrion beetle (Family Silphidae) were collected in six stations east of a kraft paper mill in Thunder Bay, Ontario, from May to August, 1971. The beetle population decreased markedly towards the mill. There was no apparent statistical difference in size variation of specimens near the mill and those further away.

  11. Intelligent systems for KSC ground processing

    Science.gov (United States)

    Heard, Astrid E.

    1992-01-01

    The ground processing and launch of Shuttle vehicles and their payloads is the primary task of Kennedy Space Center. It is a process which is largely manual and contains little inherent automation. Business is conducted today much as it was during previous NASA programs such as Apollo. In light of new programs and decreasing budgets, NASA must find more cost effective ways in which to do business while retaining the quality and safety of activities. Advanced technologies including artificial intelligence could cut manpower and processing time. This paper is an overview of the research and development in Al technology at KSC with descriptions of the systems which have been implemented, as well as a few under development which are promising additions to ground processing software. Projects discussed cover many facets of ground processing activities, including computer sustaining engineering, subsystem monitor and diagnosis tools and launch team assistants. The deployed Al applications have proven an effectiveness which has helped to demonstrate the benefits of utilizing intelligent software in the ground processing task.

  12. Victimising of School Bullying: A Grounded Theory

    Science.gov (United States)

    Thornberg, Robert; Halldin, Karolina; Bolmsjo, Natalie; Petersson, Annelie

    2013-01-01

    The aim of this study was to investigate how individuals;who had been victims of school bullying; perceived their bullying experiences and how these had affected them; and to generate a grounded theory of being a victim of bullying at school. Twenty-one individuals, who all had prior experiences of being bullied in school for more than one year,…

  13. Grounded Theory for Creating Adolescent Readers

    Science.gov (United States)

    Tacy, Cheryl Melissa

    2017-01-01

    The purpose of this qualitative grounded theory study was to discover the impact on adolescent reading motivation as students were given an opportunity to select recreational reading material and read consistently during class time. This study also explored the motivational impact of student engagement from dialogue with peers about their reading…

  14. Straussian Grounded-Theory Method: An Illustration

    Science.gov (United States)

    Thai, Mai Thi Thanh; Chong, Li Choy; Agrawal, Narendra M.

    2012-01-01

    This paper demonstrates the benefits and application of Straussian Grounded Theory method in conducting research in complex settings where parameters are poorly defined. It provides a detailed illustration on how this method can be used to build an internationalization theory. To be specific, this paper exposes readers to the behind-the-scene work…

  15. Longevity of Emplacement Drift Ground Support Materials

    International Nuclear Information System (INIS)

    D.H.Tang

    2001-01-01

    The purpose of this analysis is to evaluate the factors affecting the longevity of emplacement drift ground support materials and to develop a basis for the selection of materials for ground support that will function throughout the preclosure period of a potential repository at Yucca Mountain. REV 01 ICN 01 of this analysis is developed in accordance with AP-3.10Q, Analyses and Models, Revision 2, ICN 4, and prepared in accordance with the Technical Work Plan for Subsurface Design Section FY 01 Work Activities (CRWMS M and O 2001a). The objective of this analysis is to update the previous analysis (CRWMS M and O 2000a) to account for related changes in the Ground Control System Description Document (CRWMS M and O 2000b), the Monitored Geologic Repository Project Description Document, which is included in the Requirements and Criteria for Implementing a Repository Design that can be Operated Over a Range of Thermal Modes (BSC 2001), input information, and in environmental conditions, and to provide updated information on candidate ground support materials. Candidate materials for ground support are carbon steel and cement grout. Steel is mainly used for steel sets, lagging, channel, rock bolts, and wire mesh. Cement grout is only considered in the case of grouted rock bolts. Candidate materials for the emplacement drift invert are carbon steel and granular natural material. Materials are evaluated for the repository emplacement drift environment based on the updated thermal loading condition and waste package design. The analysis consists of the following tasks: (1) Identify factors affecting the longevity of ground support materials for use in emplacement drifts. (2) Review existing documents concerning the behavior of candidate ground support materials during the preclosure period. (3) Evaluate impacts of temperature and radiation effects on mechanical and thermal properties of steel. Assess corrosion potential of steel at emplacement drift environment. (4

  16. Monitoring of arched sched ground layer

    International Nuclear Information System (INIS)

    Listjak, M.; Slaninka, A.; Rau, L.; Pajersky, P.

    2015-01-01

    Arched Shed was a part of controlled area of NPP A1 site in Jaslovske Bohunice (Slovakia). It had been used for temporary storage of loose radioactive waste (RAW) which has been characterized within the BIDSF project C13, Characterisation of Loose Radioactive Waste'. Stored RAW has been treated and sorted within the project ',Realization of the 2 nd stage of Decommissioning Project of NPP A1'. Area of Arched Shed represents approximately 270 m 2 (45 m x 6 m). Ground layer of the AS consists mostly of soil with solid elements (stones and gravel). The aim of monitoring was to remove the contaminated soil up to 1 m below ground level. Requirement for detail monitoring of the Arched Shed ground layer resulted from conclusions of the BIDSF project C13 which has proved that massic activity 137 Cs of soil was up to few thousands Bq·kg -1 in underground layer. Dominant easy to measure radionuclide in the soil is 137 Cs which has been used as a key radionuclide for methodology of in-situ soil monitoring. Following methods has been applied during characterization: dose rate survey, sampling from defined ground layer followed by laboratory gamma spectrometry analysis by the accredited testing laboratory of radiation dosimetry VUJE (S-219) and in-situ scintillation gamma spectrometry by 1.5''x1.5'' LaBr detector. Massic activity of the remaining soil (not excavated) comply the criteria for free release into the environment (Government Regulation of Slovak Republic 345/2006 Coll.). Area was filled up by non-contaminated soil up to the ground level of surroundings. Afterward the area was covered with geotextile and concrete panels and nowadays it is ready for further usage within the NPP A1 decommissioning project as a place for treatment, conditioning and disposal of contaminated soil and concrete. (authors)

  17. Artillery localization using networked wireless ground sensors

    Science.gov (United States)

    Swanson, David C.

    2002-08-01

    This paper presents the results of an installation of four acoustic/seismic ground sensors built using COTS computers and networking gear and operating on a continuous basis at Yuma Proving Grounds, Arizona. A description of the design can be found as well, which is essentially a Windows 2000 PC with 24-bit data acquisition, GPS timing, and environmental sensors for wind and temperature. A 4-element square acoustic array 1.8m on a side can be used to detect the time and angle of arrival of the muzzle blast and the impact explosion. A 3-component geophone allows the seismic wave direction to be estimated. The 8th channel of the 24-bit data acquisition system has a 1-pulse-per-second time signal from the GPS. This allows acoustic/seismic 'snapshots' to be coherently related from multiple disconnected ground sensor nodes. COTS 2.4 GHz frequency hopping radios (802.11 standard) are used with either omni or yagi antennas depending on the location on the range. Localization of the artillery or impact can be done by using the time and angle of arrival of the waves at 2 or more ground sensor locations. However, this straightforward analysis can be significantly complicated by weather and wind noise and is also the subject of another research contract. This work will present a general description of the COTS ground sensor installation, show example data autonomously collected including agent-based atmospheric data, and share some of the lessons learned from operating a Windows 2000 based system continuously outdoors.

  18. The Building Blocks of Life Move from Ground to Tree to Animal and Back to Ground

    Science.gov (United States)

    Davidson, E. A.

    2015-12-01

    I generally use combinations of big words to describe my science, such as biogeochemistry, ecosystem ecology, nutrient cycling, stoichiometry, tropical deforestation, land-use change, agricultural intensification, eutrophication, greenhouse gas emissions, and sustainable development. I didn't expect to use any of these words, but I was surprised that I couldn't use some others that seem simple enough to me, such as farm, plant, soil, and forest. I landed on "building blocks" as my metaphor for the forms of carbon, nitrogen, phosphorus, and other elements that I study as they cycle through and among ecosystems. I study what makes trees and other kinds of life grow. We all know that they need the sun and that they take up water from the ground, but what else do trees need from the ground? What do animals that eat leaves and wood get from the trees? Just as we need building blocks to grow our bodies, trees and animals also need building blocks for growing their bodies. Trees get part of their building blocks from the ground and animals get theirs from what they eat. When animals poop and when leaves fall, some of their building blocks return to the ground. When they die, their building blocks also go back to the ground. I also study what happens to the ground, the water, and the air when we cut down trees, kill or shoo away the animals, and make fields to grow our food. Can we grow enough food and still keep the ground, water, and air clean? I think the answer is yes, but it will take better understanding of how all of those building blocks fit together and move around, from ground to tree to animal and back to ground.

  19. 30 CFR 75.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

    Science.gov (United States)

    2010-07-01

    ... High-Voltage Distribution § 75.803 Fail safe ground check circuits on high-voltage resistance grounded systems. [Statutory Provisions] On and after September 30, 1970, high-voltage, resistance grounded systems... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe ground check circuits on high-voltage...

  20. Ground-water sample collection and analysis plan for the ground-water surveillance project

    International Nuclear Information System (INIS)

    Bryce, R.W.; Evans, J.C.; Olsen, K.B.

    1991-12-01

    The Pacific Northwest Laboratory performs ground-water sampling activities at the US Department of Energy's (DOE's) Hanford Site in support of DOE's environmental surveillance responsibilities. The purpose of this document is to translate DOE's General Environmental Protection Program (DOE Order 5400.1) into a comprehensive ground-water sample collection and analysis plan for the Hanford Site. This sample collection and analysis plan sets forth the environmental surveillance objectives applicable to ground water, identifies the strategy for selecting sample collection locations, and lists the analyses to be performed to meet those objectives

  1. Ground water currents: Developments in innovative ground water treatment, March 1994

    Energy Technology Data Exchange (ETDEWEB)

    Eilers, R.

    1994-03-01

    ;Contents: Hydrodynamic cavitation oxidation destroys organics; Biosparging documented in fuel remediation study; Surfactant flushing research to remove organic liquids from aquifers; and Compilation of Ground-Water Models (a book review).

  2. The 15th Annual Intelligent Ground Vehicle Competition: Intelligent Ground Robots Created by Intelligent Students

    National Research Council Canada - National Science Library

    Theisen, Bernard L

    2007-01-01

    The Intelligent Ground Vehicle Competition (IGVC) is one of three, unmanned systems, student competitions that were founded by the Association for Unmanned Vehicle Systems International (AUVSI) in the 1990s...

  3. The 15th Annual Intelligent Ground Vehicle Competition: Intelligent Ground Robots Created by Intelligent Students

    National Research Council Canada - National Science Library

    Theisen, Bernard L

    2007-01-01

    ..., and mobile platform fundamentals to design and build an unmanned system. Teams from around the world focus on developing a suite of dual-use technologies to equip ground vehicles of the future with intelligent driving capabilities...

  4. Research of grounding capacitive current of neutral non-grounding auxiliary system in nuclear power plants

    International Nuclear Information System (INIS)

    Yang Shan; Liu Li; Huang Xiaojing

    2014-01-01

    In the domestic and abroad standards, the grounding capacitive current limitation in the non-grounding electric auxiliary system is less than 10 A. Limiting capacitive current in the standard aims to speed up the arc extinguishing to reduce the duration of arc over-voltage, but not to prevent the arc producing, The arc over-voltage harm is related to the multiple, frequency and duration of the over-voltage. When the insulation vulnerabilities appear in the equipment, the arc over-voltage may result in insulation vulnerabilities of the electrical equipment breakdown, which leads to multiple, short-circuit accidents. The cable connector, accessory and electromotor winding are all insulation vulnerabilities. Setting the arc suppression coil which can counteract the grounding capacitive current makes the arc vanish quickly. Using the casting bus which remarkably reduces the ground capacitance of the electric transmission line makes the equipment safer. (authors)

  5. Performance Analysis of Slinky Horizontal Ground Heat Exchangers for a Ground Source Heat Pump System

    Directory of Open Access Journals (Sweden)

    Md. Hasan Ali

    2017-10-01

    Full Text Available This paper highlights the thermal performance of reclined (parallel to ground surface and standing (perpendicular to ground surface slinky horizontal ground heat exchangers (HGHEs with different water mass flow rates in the heating mode of continuous and intermittent operations. A copper tube with an outer surface protected with low-density polyethylene was selected as the tube material of the ground heat exchanger. Effects on ground temperature around the reclined slinky HGHE due to heat extraction and the effect of variation of ground temperatures on reclined HGHE performance are discussed. A higher heat exchange rate was experienced in standing HGHE than in reclined HGHE. The standing HGHE was affected by deeper ground temperature and also a greater amount of backfilled sand in standing HGHE (4.20 m3 than reclined HGHE (1.58 m3, which has higher thermal conductivity than site soil. For mass flow rate of 1 L/min with inlet water temperature 7 °C, the 4-day average heat extraction rates increased 45.3% and 127.3%, respectively, when the initial average ground temperatures at 1.5 m depth around reclined HGHE increased from 10.4 °C to 11.7 °C and 10.4 °C to 13.7 °C. In the case of intermittent operation, which boosted the thermal performance, a short time interval of intermittent operation is better than a long time interval of intermittent operation. Furthermore, from the viewpoint of power consumption by the circulating pump, the intermittent operation is more efficient than continuous operation.

  6. Exogenous spatial attention influences figure-ground assignment.

    Science.gov (United States)

    Vecera, Shaun P; Flevaris, Anastasia V; Filapek, Joseph C

    2004-01-01

    In a hierarchical stage account of vision, figure-ground assignment is thought to be completed before the operation of focal spatial attention. Results of previous studies have supported this account by showing that unpredictive, exogenous spatial precues do not influence figure-ground assignment, although voluntary attention can influence figure-ground assignment. However, in these studies, attention was not summoned directly to a region in a figure-ground display. In three experiments, we addressed the relationship between figure-ground assignment and visuospatial attention. In Experiment 1, we replicated the finding that exogenous precues do not influence figure-ground assignment when they direct attention outside of a figure-ground stimulus. In Experiment 2, we demonstrated that exogenous attention can influence figure-ground assignment if it is directed to one of the regions in a figure-ground stimulus. In Experiment 3, we demonstrated that exogenous attention can influence figure-ground assignment in displays that contain a Gestalt figure-ground cue; this result suggests that figure-ground processes are not entirely completed prior to the operation of focal spatial attention. Exogenous spatial attention acts as a cue for figure-ground assignment and can affect the outcome of figure-ground processes.

  7. Ground rubber: Sorption media for ground water containing benzene and O-xylene

    International Nuclear Information System (INIS)

    Kershaw, D.S.; Pamukcu, S.

    1997-01-01

    The purpose of the current study is to examine the ability of ground rubber to sorb benzene and O-xylene from water contained with aromatic hydrocarbons. The study consisted of running both batch and packed bed column tests to determine the sorption capacity, the required sorption equilibration time, and the flow through utilization efficiency of ground rubber under various contact times when exposed to water contaminated with various amounts of benzene or O-xylene. Initial batch test results indicate that ground rubber can attain equilibrium sorption capacities up to 1.3 or 8.2 mg of benzene or O-xylene, respectively, per gram of tire rubber at solution equilibrium concentrations of 10 mg/L. Packed bed column tests indicate that ground tire rubber has on the average a 40% utilization rate when a hydraulic residence time of 15 min is used. Possible future uses of round rubber as a sorption media could include, but are not limited to, the use of ground rubber as an aggregate in slurry cutoff walls that are in contact with petroleum products. Ground rubber could also be used as a sorption media in pump-and-treat methodologies or as a sorption media in in-situ reactive permeable barriers

  8. TESS Ground System Operations and Data Products

    Science.gov (United States)

    Glidden, Ana; Guerrero, Natalia; Fausnaugh, Michael; TESS Team

    2018-01-01

    We describe the ground system operations for processing data from the Transiting Exoplanet Survey Satellite (TESS), highlighting the role of the Science Operations Center (SOC). TESS is a spaced-based (nearly) all-sky mission, designed to find small planets around nearby bright stars using the transit method. We detail the flow of data from pixel measurements on the instrument to final products available at the Mikulski Archive for Space Telescopes (MAST). The ground system relies on a host of players to process the data, including the Payload Operations Center at MIT, the Science Processing Operation Center at NASA Ames, and the TESS Science Office, led by the Harvard-Smithsonian Center for Astrophysics and MIT. Together, these groups will deliver TESS Input Catalog, instrument calibration models, calibrated target pixels and full frame images, threshold crossing event reports, two-minute light curves, and the TESS Objects of Interest List.

  9. Space and Ground-Based Infrastructures

    Science.gov (United States)

    Weems, Jon; Zell, Martin

    This chapter deals first with the main characteristics of the space environment, outside and inside a spacecraft. Then the space and space-related (ground-based) infrastructures are described. The most important infrastructure is the International Space Station, which holds many European facilities (for instance the European Columbus Laboratory). Some of them, such as the Columbus External Payload Facility, are located outside the ISS to benefit from external space conditions. There is only one other example of orbital platforms, the Russian Foton/Bion Recoverable Orbital Capsule. In contrast, non-orbital weightless research platforms, although limited in experimental time, are more numerous: sounding rockets, parabolic flight aircraft, drop towers and high-altitude balloons. In addition to these facilities, there are a number of ground-based facilities and space simulators, for both life sciences (for instance: bed rest, clinostats) and physical sciences (for instance: magnetic compensation of gravity). Hypergravity can also be provided by human and non-human centrifuges.

  10. Case study on ground water flow (8)

    International Nuclear Information System (INIS)

    1999-02-01

    The report comprises research activities made in fiscal year 1997 under the contract of Japan Nuclear Fuel Cycle Development Center and the main items are: (1) Evaluation of water permeability through discontinuous hard bedrock in deep strata in relevant with underground disposal of radioactive wastes, (2) Three dimensional analysis of permeated water in bedrock, including flow analysis in T ono district using neuro-network and modification of Evaporation Logging System, (3) Development of hydraulic tests and necessary equipment applicable to measurements of complex dielectric constants of contaminated soils using FUDR-V method, this giving information on soil component materials, (4) Investigation methods and modeling of hydraulics in deep strata, (5) Geological study of ground water using environmental isotopes such as 14 C, 36 Cl and 4 He, particularly measurement of ages of ground water using an accelerator-mass spectrometer, and (6) Re-submerging phenomena affecting the long-term geological stability. (S. Ohno)

  11. Trapping cold ground state argon atoms.

    Science.gov (United States)

    Edmunds, P D; Barker, P F

    2014-10-31

    We trap cold, ground state argon atoms in a deep optical dipole trap produced by a buildup cavity. The atoms, which are a general source for the sympathetic cooling of molecules, are loaded in the trap by quenching them from a cloud of laser-cooled metastable argon atoms. Although the ground state atoms cannot be directly probed, we detect them by observing the collisional loss of cotrapped metastable argon atoms and determine an elastic cross section. Using a type of parametric loss spectroscopy we also determine the polarizability of the metastable 4s[3/2](2) state to be (7.3±1.1)×10(-39)  C m(2)/V. Finally, Penning and associative losses of metastable atoms in the absence of light assisted collisions, are determined to be (3.3±0.8)×10(-10)  cm(3) s(-1).

  12. Grounding the Innovation of Future Technologies

    Directory of Open Access Journals (Sweden)

    Antti Oulasvirta

    2005-01-01

    Full Text Available Mobile and ubiquitous technologies can potentially change the role of information and communication technology in human lives. Empirical, human-centered approaches are emerging as an alternative to technology-driven approaches in the innovation of these technologies. Three necessary empirical stages, intertwined with analytical ones and with each informing and grounding the succeeding stages, are analyzed. First, needfinding is utilized to discover societal and individual demands for technology. Second, observational and experimental studies examine the social and cognitive preconditions for interaction. From these two steps, a hypothesis is formulated regarding how technology will change existing practices. Finally, this hypothesis, embodied in the design of a prototype, is tested in a field trial. Four design cases illustrate the value of empirical grounding.

  13. SRS Burial Ground Complex: Remediation in Progress

    International Nuclear Information System (INIS)

    Griffin, M.; Crapse, B.; Cowan, S.

    1998-01-01

    Closure of the various areas in the Burial Ground Complex (BGC) represents a major step in the reduction of risk at the Savannah River Site (SRS) and a significant investment of resources. The Burial Ground Complex occupies approximately 195 acres in the central section of the SRS. Approximately 160 acres of the BGC consists of hazardous and radioactive waste disposal sites that require remediation. Of these source acres, one-third have been remediated while two-thirds are undergoing interim or final action. These restoration activities have been carried out in a safe and cost effective manner while minimizing impact to operating facilities. Successful completion of these activities is in large part due to the teamwork demonstrated by the Department of Energy, contractor/subcontractor personnel, and the regulatory agencies. The experience and knowledge gained from the closure of these large disposal facilities can be used to expedite closure of similar facilities

  14. Case study on ground water flow (8)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-02-01

    The report comprises research activities made in fiscal year 1997 under the contract of Japan Nuclear Fuel Cycle Development Center and the main items are: (1) Evaluation of water permeability through discontinuous hard bedrock in deep strata in relevant with underground disposal of radioactive wastes, (2) Three dimensional analysis of permeated water in bedrock, including flow analysis in T ono district using neuro-network and modification of Evaporation Logging System, (3) Development of hydraulic tests and necessary equipment applicable to measurements of complex dielectric constants of contaminated soils using FUDR-V method, this giving information on soil component materials, (4) Investigation methods and modeling of hydraulics in deep strata, (5) Geological study of ground water using environmental isotopes such as {sup 14}C, {sup 36}Cl and {sup 4}He, particularly measurement of ages of ground water using an accelerator-mass spectrometer, and (6) Re-submerging phenomena affecting the long-term geological stability. (S. Ohno)

  15. Single-event effect ground test issues

    International Nuclear Information System (INIS)

    Koga, R.

    1996-01-01

    Ground-based single event effect (SEE) testing of microcircuits permits characterization of device susceptibility to various radiation induced disturbances, including: (1) single event upset (SEU) and single event latchup (SEL) in digital microcircuits; (2) single event gate rupture (SEGR), and single event burnout (SEB) in power transistors; and (3) bit errors in photonic devices. These characterizations can then be used to generate predictions of device performance in the space radiation environment. This paper provides a general overview of ground-based SEE testing and examines in critical depth several underlying conceptual constructs relevant to the conduct of such tests and to the proper interpretation of results. These more traditional issues are contrasted with emerging concerns related to the testing of modern, advanced microcircuits

  16. Procedures for ground-water investigations

    International Nuclear Information System (INIS)

    1989-09-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water investigations are carried out to fulfill the requirements for the US Department of Energy (DOE) to meet the requirements of DOE Orders. Investigations are also performed for various clients to meet the requirements of the Resource Conservation and Recovery Act of 1976 (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). National standards including procedures published by the American Society for Testing and Materials (ASTM) and the US Geological Survey were utilized in developing the procedures contained in this manual

  17. Trampoline effect in extreme ground motion.

    Science.gov (United States)

    Aoi, Shin; Kunugi, Takashi; Fujiwara, Hiroyuki

    2008-10-31

    In earthquake hazard assessment studies, the focus is usually on horizontal ground motion. However, records from the 14 June 2008 Iwate-Miyagi earthquake in Japan, a crustal event with a moment magnitude of 6.9, revealed an unprecedented vertical surface acceleration of nearly four times gravity, more than twice its horizontal counterpart. The vertical acceleration was distinctly asymmetric; the waveform envelope was about 1.6 times as large in the upward direction as in the downward direction, which is not explained by existing models of the soil response. We present a simple model of a mass bouncing on a trampoline to account for this asymmetry and the large vertical amplitude. The finding of a hitherto-unknown mode of strong ground motion may prompt major progress in near-source shaking assessments.

  18. Grounding and shielding circuits and interference

    CERN Document Server

    Morrison, Ralph

    2016-01-01

    Applies basic field behavior in circuit design and demonstrates how it relates to grounding and shielding requirements and techniques in circuit design This book connects the fundamentals of electromagnetic theory to the problems of interference in all types of electronic design. The text covers power distribution in facilities, mixing of analog and digital circuitry, circuit board layout at high clock rates, and meeting radiation and susceptibility standards. The author examines the grounding and shielding requirements and techniques in circuit design and applies basic physics to circuit behavior. The sixth edition of this book has been updated with new material added throughout the chapters where appropriate. The presentation of the book has also been rearranged in order to reflect the current trends in the field.

  19. TARDEC Overview: Ground Vehicle Power and Mobility

    Science.gov (United States)

    2011-02-04

    Fuel & Water Distribution • Force Sustainment • Construction Equipment • Bridging • Assured Mobility Systems Robotics • TALON • PackBot • MARCbot...Equipment • Mechanical Countermine Equipment • Tactical Bridging Intelligent Ground Systems • Autonomous Robotics Systems • Safe Operations...Test Cell • Hybrid Electric Reconfigurable Moveable Integration Testbed (HERMIT) • Electro-chemical Analysis and Research Lab (EARL) • Battery Lab • Air

  20. Activation analysis of ground water of Chandigarh

    International Nuclear Information System (INIS)

    Mittal, V.K.

    1997-01-01

    Ground water samples from Chandigarh were analysed for 22 trace elements using neutron activation analysis (NAA) technique. These samples were drawn from shallow aquifers using hand pumps. It was found that for most of the elements the concentrations were well within the ISI/WHO recommended values. However, samples collected from the industrial belt of the city showed higher concentrations of trace elements, particularly some toxic ones. (author). 6 refs., 1 tab