Science.gov

Sample records for neutron rem meters

  1. Pocket neutron REM meter

    SciTech Connect

    Quam, W.; Del Duca, T.; Plake, W.; Graves, G.; DeVore, T.; Warren, J.

    1982-01-01

    This paper describes a pocket-calculator-sized, neutron-sensitive, REM-responding personnel dosimeter that uses three tissue-equivalent cylindrical proportional counters as neutron-sensitive detectors. These are conventionally called Linear Energy Transfer (LET) counters. Miniaturized hybrid circuits are used for the linear pulse handling electronics, followed by a 256-channel ADC. A CMOS microprocessor is used to calculate REM exposure from the basic rads-tissue data supplied by the LET counters and also to provide timing and display functions. The instrument is used to continuously accumulate time in hours since reset, total counts accumulated, rads-tissue, and REM. At any time the user can display any one of these items or a channel number (an aid in calibration). The instrument provides such data with a precision of +- 3% for a total exposure of 1 mREM over 8 hours.

  2. Pocket neutron REM meter

    SciTech Connect

    Quam, W.; Del Duca, T.; Plake, W.; Graves, G.; DeVore, T.; Warren, J.

    1982-01-01

    This paper describes a pocket-calculator-sized, neutron-sensitive, REM-responding personnel dosimeter that uses three tissue-equivalent cylindrical proportional counters as neutron-sensitive detectors. These are conventionally called Linear Energy Transfer (LET) counters. Miniaturized hybrid circuits are used for the linear pulse handling electronics, followed by a 256-channel ADC. A CMOS microprocessor is used to calculate REM exposure from the basic rads-tissue data supplied by the LET counters and also to provide timing and display functions. The instrument is used to continuously accumulate time in hours since reset, total counts accumulated, rads-tissue, and REM. The user can display any one of these items or a channel number (an aid in calibration) at any time. Such data are provided with a precision of +- 3% for a total exposure of 1 mREM over eight hours.

  3. Proton recoil scintillator neutron rem meter

    DOEpatents

    Olsher, Richard H.; Seagraves, David T.

    2003-01-01

    A neutron rem meter utilizing proton recoil and thermal neutron scintillators to provide neutron detection and dose measurement. In using both fast scintillators and a thermal neutron scintillator the meter provides a wide range of sensitivity, uniform directional response, and uniform dose response. The scintillators output light to a photomultiplier tube that produces an electrical signal to an external neutron counter.

  4. Neutron dose equivalent meter

    DOEpatents

    Olsher, Richard H.; Hsu, Hsiao-Hua; Casson, William H.; Vasilik, Dennis G.; Kleck, Jeffrey H.; Beverding, Anthony

    1996-01-01

    A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

  5. Response of six neutron survey meters in mixed fields of fast and thermal neutrons.

    PubMed

    Kim, S I; Kim, B H; Chang, I; Lee, J I; Kim, J L; Pradhan, A S

    2013-10-01

    Calibration neutron fields have been developed at KAERI (Korea Atomic Energy Research Institute) to study the responses of commonly used neutron survey meters in the presence of fast neutrons of energy around 10 MeV. The neutron fields were produced by using neutrons from the (241)Am-Be sources held in a graphite pile and a DT neutron generator. The spectral details and the ambient dose equivalent rates of the calibration fields were established, and the responses of six neutron survey meters were evaluated. Four single-moderator-based survey meters exhibited an under-responses ranging from ∼9 to 55 %. DINEUTRUN, commonly used in fields around nuclear reactors, exhibited an over-response by a factor of three in the thermal neutron field and an under-response of ∼85 % in the mixed fields. REM-500 (tissue-equivalent proportional counter) exhibited a response close to 1.0 in the fast neutron fields and an under-response of ∼50 % in the thermal neutron field.

  6. Critical review of directional neutron survey meters

    NASA Astrophysics Data System (ADS)

    Balmer, Matthew J. I.; Gamage, Kelum A. A.; Taylor, Graeme C.

    2014-01-01

    Having been overlooked for many years, research is now starting to take into account the directional distribution of the neutron work place field. The impact of not taking this into account has led to overly conservative estimates of dose in neutron workplace fields. This paper provides a critical review of this existing research into directional survey meters which could improve these estimates of dose. Instruments which could be adapted for use as directional neutron survey meters are also considered within this review. Using Monte-Carlo techniques, two of the most promising existing designs are evaluated; a boron-doped liquid scintillator and a multi-detector directional spectrometer. As an outcome of these simulations, possible adaptations to these instruments are suggested with a view to improving the portability of the instrument.

  7. DOSIMETRIC response of a REM-500 in low energy neutron fields typical of nuclear power plants.

    PubMed

    Aslam; Matysiak, W; Atanackovic, J; Waker, A J

    2012-06-01

    This study investigates the response of a REM-500 to assess neutron quality factor and dose equivalent in low energy neutron fields, which are commonly encountered in the workplace environment of nuclear power stations. The McMaster University 3 MV Van de Graaff accelerator facility was used to measure the response of the instrument in monoenergetic neutron fields in the energy range 51 to 727 keV by bombarding a thin LiF target with 1.93-2.50 MeV protons. The energy distribution of the neutron fields produced in the facility was measured by a (3)He filled gas ionization chamber. The MCA mode of the REM-500 instrument was used to collect lineal energy distributions at varying neutron energies and to calculate the frequency and dose-mean lineal energies. The effective quality factor, Q-, was also calculated using the values of Q(y)listed in the REM-500 operation manual and compared with those of ICRP 60. The authors observed a continuously increasing trend in y - F, y-D, and Q-with an increase in neutron energy. It is interesting to note that standard tissue equivalent proportional counters (TEPCs) filled with tissue equivalent(TE) gas give rise to a similar trend for these microdosimetric quantities of interest in the same energy range; however, the averages calculated in this study are larger by about 15%compared to a TEPC filled with propane-based TE gas probably because of the larger stopping power of protons in propane compared to TE gas. These somewhat larger event sizes did not result in any significant increase in the Q-compared to those obtained from a TEPC filled with TE gas and were found to be in good agreement with other measurements reported earlier at corresponding neutron energies. The instrument quality factor response, R(Q), defined as the ratio of measured quality factor to the calculated quality factor in an ICRU tissue sphere,was found to vary with neutron energy. The instrument response,R(Q), was ~0.6 at 727 keV, which deteriorates further to

  8. Advances in personnel neutron dosimetry: part 2

    SciTech Connect

    Vallario, E.; Faust, L.

    1983-08-01

    A continuation of the advances in personnel neutron dosimetry research programs and technology transfer reviews work on active dosimeters, electronic devices that determine the dose equivalent to a worker during an exposure to neutron radiation. Active dosemeters are routinely used for gamma radiation dosimetry. Experience with neutron-sensitive pocket rem-meters at several DOE laboratories covers three prototypes. Pocket rem-meters work well for detecting neutrons over a wide energy range. They give instantaneous readout of the accumulated neutron dose-equivalent. 1 figure.

  9. Fission meter and neutron detection using poisson distribution comparison

    DOEpatents

    Rowland, Mark S; Snyderman, Neal J

    2014-11-18

    A neutron detector system and method for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. Comparison of the observed neutron count distribution with a Poisson distribution is performed to distinguish fissile material from non-fissile material.

  10. WE-AB-BRB-11: Portable Fast Neutron and Photon Dose Meter

    SciTech Connect

    Miller, C A; Clarke, S D; Pozzi, S A

    2015-06-15

    Purpose: To develop an instrument for measuring neutron and photon dose rates from mixed fields with a single device. Methods: Stilbene organic scintillators can be used to detect fast neutrons and photons. Stilbene was used to measure emission from mixed particle sources californium-252 (Cf-252) and plutonium-beryllium (PuBe). Many source detector configurations were used, along with varying amounts of shielding. Collected spectra were analyzed using pulse shape discrimination software, to separate neutron and photon interactions. With a measured light output to energy relationship the pulse height spectrum was converted to energy deposited in the detector. Energy deposited was converted to dose with a variety of standard dose factors, for comparison to current methods. For validation, all measurements and processing was repeated using an EJ-309 liquid scintillator detector. Dose rates were also measured in the same configuration with commercially available dose meters for further validation. Results: Measurements of dose rates will show agreement across all methods. Higher accuracy of pulse shape discrimination at lower energies with stilbene leads to more accurate measurement of neutron and photon deposited dose. In strong fields of mixed particles discrimination can be performed well at a very low energy threshold. This shows accurate dose measurements over a large range of incident particle energy. Conclusion: Stilbene shows promise as a material for dose rate measurements due to its strong ability for separating neutrons and photon pulses and agreement with current methods. A dual particle dose meter would simplify methods which are currently limited to the measurement of only one particle type. Future work will investigate the use of a silicon photomultiplier to reduce the size and required voltage of the assembly, for practical use as a handheld survey meter, room monitor, or phantom installation. Funding From the United States Department of Energy and the

  11. Sensitivity and uncertainty in the measurement of H*(10) in neutron fields using an REM500 and a multi-element TEPC.

    PubMed

    Waker, Anthony; Taylor, Graeme

    2014-10-01

    The REM500 is a commercial instrument based on a tissue-equivalent proportional counter (TEPC) that has been successfully deployed as a hand-held neutron monitor, although its sensitivity is regarded by some workers as low for nuclear power plant radiation protection work. Improvements in sensitivity can be obtained using a multi-element proportional counter design in which a large number of small detecting cavities replace the single large volume cavity of conventional TEPCs. In this work, the authors quantify the improvement in uncertainty that can be obtained by comparing the ambient dose equivalent measured with a REM500, which utilises a 5.72 cm (2(1/4) inch) diameter Rossi counter, with that of a multi-element TEPC designed to have the sensitivity of a 12.7 cm (5 inch) spherical TEPC. The results obtained also provide some insight into the influence of other design features of TEPCs, such as geometry and gas filling, on the measurement of ambient dose equivalent.

  12. Status Report on the Passive Neutron Enrichment Meter (PNEM) for UF6 Cylinder Assay

    SciTech Connect

    Miller, Karen A.; Swinhoe, Martyn T.; Menlove, Howard O.; Marlow, Johnna B.

    2012-05-02

    The Passive Neutron Enrichment Meter (PNEM) is a nondestructive assay (NDA) system being developed at Los Alamos National Laboratory (LANL). It was designed to determine {sup 235}U mass and enrichment of uranium hexafluoride (UF{sub 6}) in product, feed, and tails cylinders (i.e., 30B and 48Y cylinders). These cylinders are found in the nuclear fuel cycle at uranium conversion, enrichment, and fuel fabrication facilities. The PNEM is a {sup 3}He-based neutron detection system that consists of two briefcase-sized detector pods. A photograph of the system during characterization at LANL is shown in Fig. 1. Several signatures are currently being studied to determine the most effective measurement and data reduction technique for unfolding {sup 235}U mass and enrichment. The system collects total neutron and coincidence data for both bare and cadmium-covered detector pods. The measurement concept grew out of the success of the Uranium Cylinder Assay System (UCAS), which is an operator system at Rokkasho Enrichment Plant (REP) that uses total neutron counting to determine {sup 235}U mass in UF{sub 6} cylinders. The PNEM system was designed with higher efficiency than the UCAS in order to add coincidence counting functionality for the enrichment determination. A photograph of the UCAS with a 48Y cylinder at REP is shown in Fig. 2, and the calibration measurement data for 30B product and 48Y feed and tails cylinders is shown in Fig. 3. The data was collected in a low-background environment, meaning there is very little scatter in the data. The PNEM measurement concept was first presented at the 2010 Institute of Nuclear Materials Management (INMM) Annual Meeting. The physics design and uncertainty analysis were presented at the 2010 International Atomic Energy Agency (IAEA) Safeguards Symposium, and the mechanical and electrical designs and characterization measurements were published in the ESARDA Bulletin in 2011.

  13. PING Gamma Ray and Neutron Measurements of a Meter-Sized Carbonaceous Asteroid Analog

    NASA Technical Reports Server (NTRS)

    Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S.; Lim, L.; McClanahan, T.; Namkung, M.; Nowicki, S.; Parsons, A.; Schweitzer, J.; Starr, R.; Trombka, J.

    2011-01-01

    Determining the elemental composition of carbonaceous (spectral type C) asteroids is still one of the basic problems when studying these objects. The only main source of elemental composition information for asteroids is from their optical, NIR and IR properties, which include their spectral reflectance characteristics, albedo, polarization, and the comparison of optical spectroscopy with meteorite groups corresponding to asteroids of every spectral type. Unfortunately, these sources reflect observations from widely contrasting spatial scales that presently yield a void in the continuum of microscopic and macroscopic evidence, a lack of in situ measurement confirmation, and require deeper sensing techniques to discern the nature of these asteroids. The Probing In situ with Neutrons and Gamma rays (PING) instrument is ideally suited to address this problem because it can be used to determine the bulk elemental composition, H and C content, the average atomic weight and density of the surface and subsurface layers of C-type asteroids, and can provide measurements used to determine the difference between and distinguish between different types of asteroids. We are currently developing the PING instrument that combines gamma ray and neutron detectors with a 14 Me V pulsed neutron generator to determine the in-situ bulk elemental abundances and geochemistry of C-type asteroids with a spatial resolution of 1 m down to depths of tens of cm to 1 m. One aspect of the current work includes experimentally testing and optimizing PING on a known meter-sized Columbia River basalt C-type asteroid analog sample that has a similar composition and the same neutron response as that of a C-type asteroid. An important part of this effort focuses on utilizing timing measurements to isolate gamma rays produced by neutron inelastic scattering, neutron capture and delayed activation processes. Separating the gamma ray spectra by nuclear processes results in higher precision and sensitivity

  14. Neutron spectra as a function of angle at two meters from the Little Boy assembly

    SciTech Connect

    Griffith, R.V.; Huntzinger, C.J.; Thorngate, J.H.

    1984-07-02

    Measurements of neutron spectra produced by the Los Alamos National Laboratory (LANL) Little Boy replica assembly (Comet) were made with a combined multisphere and liquid scintillator system, that has been widely used at the Lawrence Livermore National Laboratory. The combined system was used for measurements at the side (90/sup 0/) and nose (0/sup 0/) of the assembly; additional measurements were made at 45/sup 0/ using only the liquid scintillator. Data were obtained at two meters from the center of the reactive region of the assembly, with good agreement between the multisphere and scintillator results. Comparison with liquid scintillator measurements performed by experimenters from the Canadian Defence Research Establishment, Ottawa (DREO) and calculations from LANL depended on the specific angle, obtaining the best agreement at 90/sup 0/. 32 references, 11 figures, 4 tables.

  15. Characterization and Comparison of New Concepts in Neutron Detection

    DTIC Science & Technology

    2010-05-12

    thermoluminescent dosimeter u atomic mass unit USNA United States Naval Academy Xe xenon XeF2 xenon diflouride x Chapter 1 Neutron-Detection Systems...human tissue, and as area monitors (or rem-meters). Specifically, the United States Navy uses the DT-702 thermoluminescent dosimeter (TLD) to measure

  16. Advances in personnel neutron dosimetry

    SciTech Connect

    Vallario, E.; Faust, L.

    1983-07-01

    A program to assess current personnel neutron dosimeter capabilities and to develop improved personnel neutron dosimeters examines the two types of passive dosimeters in use at DOE facilities: NTA film and TLD-albedo dosimeters. Two new neutron dosimeters under development to overcome some of their problems are combination/track-etch dosimeters and pocket rem-meters. The DOE program is investigating new materials and improved manufacturing processes using the CR-39 polymer and that is nearly free of surface defects. 1 figure.

  17. [A new correction method for radionuclide formation in neutron activation analysis using a reactor power meter coupled with a microcomputer].

    PubMed

    Hirai, S; Yoshino, Y; Suzuki, S; Horiuchi, N

    1982-05-01

    Neutron flux and irradiation time should be accurately known in neutron activation analysis using very short lived nuclides in which conventional monitoring methods i.e., a comparator method, flux monitor method and so on cannot be used satisfactorily. Especially, fluctuation of neutron flux has not been corrected. We noted a change of reactor power at a pneumatic operation, and found out a new correction method for its correction in activation analysis. In our small nuclear reactor, TRIGA-II, the reactor power increased rapidly a few % when a pneumatic-operated capsule arrived at a core of the reactor, and decreased when the capsule left from the core. If the duration between these two changes of the reactor power is equal to the irradiation time, and that the reactor power is proportional to the neutron flux, we can regard an activity formation as a time integration of the reactor power. Then, the correction system was made of a reactor power meter, a V-F converter (voltage to frequency converter), a clock time, a counter, a microcomputer, electric circuits and so on. The signal of the reactor power during the irradiation was counted through the V-F converter, and was accumulated in a memory of the microcomputer. The neutron fluence was calculated in this microcomputer. This method was examined by means of activation of copper and selenium standard samples by 9-11 sec irradiations. The observed activity involved +/- 10% error. However, the error in the corrected activity was decreased to a few % using this correction method. As a result, we found that this method can be used to obtain accurate value for radionuclide formation.

  18. Long-term Passive Mode Data Measured by the Dynamic Albedo of Neutrons (DAN) Instrument onboard Mars Science Laboratory (MSL) and Comparison to REMS Surface Pressure and Temperature Measurements

    NASA Astrophysics Data System (ADS)

    Jun, I.; Mitrofanov, I. G.; Litvak, M. L.; Sanin, A. B.; Martín-Torres, J.; Zorzano, M. P.; Boynton, W. V.; Fedosov, F.; Golovin, D.; Hardgrove, C. J.; Harshman, K.; Kozyrev, A.; Kuzmin, R.; Malakhov, A. V.; Mischna, M. A.; Moersch, J.; Mokrousov, M.; Nikiforov, S.; Tate, C. G.

    2014-12-01

    Since the landing in August 2012, DAN has provided a wealth of scientific data from the successful surface operation in both Active mode and Passive mode. While the main DAN science investigation so far has focused in estimating the contents of water-equivalent-hydrogen (WEH) and chlorine-equivalent-neutron-absorption in the surface, here we will provide/discuss low energy (less than about 1 keV) background neutron environment at the Martian surface as measured by DAN Passive mode operation. Passive mode measurements have been done on almost every sols with durations ranging from 1 hour to ~9 hour, covering different times of a day. Neutrons from the onboard power source Multi Mission Radioisotope Thermonuclear Generator (MMRTG) and induced by Galactic Cosmic Ray (GCR)/Solar Energetic Particles (SEP) interactions with the Martian atmosphere and the surface material contribute to the DAN passive data. An approach to separate out the respective contributions from the DAN total count rates was developed previously (Jun et al., 2013) using the data collected at Rocknest (where the rover stayed from sol 60 to sol 100). The main goal of this paper is to extend the same analysis to other locations encountered during the rover traverse especially to understand the long-term (through Sol 800, covering more than 1 Martian year) behavior of the neutron environment at the Martian surface as measured by DAN in response to variation of the free space GCR/SEP environment. Extensive Monte Carlo transport simulations using Monte Carlo N-Particle eXtended (MCNPX) have been performed to support the analysis and to aid interpretation of the DAN passive data. In addition, the DAN passive data are compared to the long-term surface temperature and pressure data (both measured and modeled) from Rover Environmental Monitoring Station (REMS) to investigate possible correlation of the DAN data with ambient environmental conditions.

  19. Responses of selected neutron monitors to cosmic radiation at aviation altitudes.

    PubMed

    Yasuda, Hiroshi; Yajima, Kazuaki; Sato, Tatsuhiko; Takada, Masashi; Nakamura, Takashi

    2009-06-01

    Cosmic radiation exposure of aircraft crew, which is generally evaluated by numerical simulations, should be verified by measurements. From the perspective of radiological protection, the most contributing radiation component at aviation altitude is neutrons. Measurements of cosmic neutrons, however, are difficult in a civilian aircraft because of the limitations of space and electricity; a small, battery-operated dosimeter is required whereas larger-size instruments are generally used to detect neutrons with a broad range of energy. We thus examined the applicability of relatively new transportable neutron monitors for use in an aircraft. They are (1) a conventional rem meter with a polyethylene moderator (NCN1), (2) an extended energy-range rem meter with a tungsten-powder mixed moderator (WENDI-II), and (3) a recoil-proton scintillation rem meter (PRESCILA). These monitors were installed onto the racks of a business jet aircraft that flew two times near Japan. Observed data were compared to model calculations using a PHITS-based Analytical Radiation Model in the Atmosphere (PARMA). Excellent agreement between measured and calculated values was found for the WENDI-II. The NCN1 showed approximately half of predicted values, which were lower than those expected from its response function. The observations made with PRESCILA showed much higher than expected values; which is attributable to the presence of cosmic-ray protons and muons. These results indicate that careful attention must be paid to the dosimetric properties of a detector employed for verification of cosmic neutron dose.

  20. REM. Rapid Eye Mount

    NASA Astrophysics Data System (ADS)

    Molinari, E.; Vergani, S. D.; Zerbi, F. M.; Covino, S.; Chincarini, G.

    2004-09-01

    REM is a robotic fast moving telescope designed to immediately point and observe in optical and IR the GRBs detected by satellites. Its immediate data gathering capabilities and its accurate astrometry will issue early alerts for the VLT.

  1. Measurement of the neutron spectrum and ambient neutron dose rate equivalent from the small 252Cf source at 1 meter

    SciTech Connect

    Radev, R.

    2015-07-07

    NASA Langley Research Center requested a measurement of the neutron spectral distribution and fluence from the 252Cf source (model NS-120, LLNL serial # 7001677, referred as the SMALL Cf source) and determination of the ambient neutron dose rate equivalent and kerma at 100 cm for the Radiation Budget Instrument Experiment (Rad-X). The dosimetric quantities should be based on the neutron spectrum and the current neutron-to-dose conversion coefficients.

  2. Rapid Measurement of Neutron Dose Rate for Transport Index

    SciTech Connect

    Morris, R.L.

    2000-02-27

    A newly available neutron dose equivalent remmeter with improved sensitivity and energy response has been put into service at Rocky Flats Environmental Technology Site (RFETS). This instrument is being used to expedite measurement of the Transport Index and as an ALARA tool to identify locations where slightly elevated neutron dose equivalent rates exist. The meter is capable of measuring dose rates as low as 0.2 {mu}Sv per hour (20 {mu}rem per hour). Tests of the angular response and energy response of the instrument are reported. Calculations of the theoretical instrument response made using MCNP{trademark} are reported for materials typical of those being shipped.

  3. REM sleep Behaviour Disorder.

    PubMed

    Ferini-Strambi, Luigi; Rinaldi, Fabrizio; Giora, Enrico; Marelli, Sara; Galbiati, Andrea

    2016-01-01

    Rapid Eye Movement (REM) sleep Behaviour Disorder (RBD) is a REM sleep parasomnia characterized by loss of the muscle atonia that typically occurs during REM sleep, therefore allowing patients to act out their dreams. RBD manifests itself clinically as a violent behaviour occurring during the night, and is detected at the polysomnography by phasic and/or tonic muscle activity on the electromyography channel. In absence of neurological signs or central nervous system lesions, RBD is defined as idiopathic. Nevertheless, in a large number of cases the development of neurodegenerative diseases in RBD patients has been described, with the duration of the follow-up representing a fundamental aspect. A growing number of clinical, neurophysiologic and neuropsychological studies aimed to detect early markers of neurodegenerative dysfunction in RBD patients. Anyway, the evidence of impaired cortical activity, subtle neurocognitive dysfunction, olfactory and autonomic impairment and neuroimaging brain changes in RBD patients is challenging the concept of an idiopathic form of RBD, supporting the idea of RBD as an early manifestation of a more complex neurodegenerative process.

  4. Breakdown in REM sleep circuitry underlies REM sleep behavior disorder.

    PubMed

    Peever, John; Luppi, Pierre-Hervé; Montplaisir, Jacques

    2014-05-01

    During rapid eye movement (REM) sleep, skeletal muscles are almost paralyzed. However, in REM sleep behavior disorder (RBD), which is a rare neurological condition, muscle atonia is lost, leaving afflicted individuals free to enact their dreams. Although this may sound innocuous, it is not, given that patients with RBD often injure themselves or their bed-partner. A major concern in RBD is that it precedes, in 80% of cases, development of synucleinopathies, such as Parkinson's disease (PD). This link suggests that neurodegenerative processes initially target the circuits controlling REM sleep. Clinical and basic neuroscience evidence indicates that RBD results from breakdown of the network underlying REM sleep atonia. This finding is important because it opens new avenues for treating RBD and understanding its link to neurodegenerative disorders.

  5. REM-containing silicate concentrates

    NASA Astrophysics Data System (ADS)

    Pavlov, V. F.; Shabanova, O. V.; Pavlov, I. V.; Pavlov, M. V.; Shabanov, A. V.

    2016-01-01

    A new method of advanced complex processing of ores containing rare-earth elements (REE) is proposed to obtain porous X-ray amorphous aluminosilicate material with a stable chemical composition which concentrates oxides of rare-earth metals (REM). The ferromanganese oxide ores of Chuktukon deposit (Krasnoyarsk Region, RF) were used for the experiment. The obtained aluminosilicate material is appropriate for treatment with 5 - 15% solutions of mineral acids to leach REM.

  6. REM sleep homeostasis in the absence of REM sleep: Effects of antidepressants.

    PubMed

    McCarthy, Andrew; Wafford, Keith; Shanks, Elaine; Ligocki, Marcin; Edgar, Dale M; Dijk, Derk-Jan

    2016-09-01

    Most antidepressants suppress rapid eye movement (REM) sleep, which is thought to be important to brain function, yet the resulting REM sleep restriction is well tolerated. This study investigated the impact of antidepressants with different mechanisms of action, such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCA), on the regulation of REM sleep in rats. REM sleep was first demonstrated to be homeostatically regulated using 5, 8 and 10 h of REM-sleep specific restriction through EEG-triggered arousals, with an average of 91 ± 10% of lost REM sleep recovered following a 26-29 -hour recovery period. Acute treatment with the antidepressants paroxetine, citalopram and imipramine inhibited REM sleep by 84 ± 8, 84 ± 8 and 69 ± 9% respectively relative to vehicle control. The pharmacologically-induced REM sleep deficits by paroxetine and citalopram were not fully recovered, whereas, after imipramine the REM sleep deficit was fully compensated. Given the marked difference between REM sleep recovery following the administration of paroxetine, citalopram, imipramine and REM sleep restriction, the homeostatic response was further examined by pairing REM sleep specific restriction with the three antidepressants. Surprisingly, the physiologically-induced REM sleep deficits incurred prior to suppression of REM sleep by all antidepressants was consistently recovered. The data indicate that REM sleep homeostasis remains operative following subsequent treatment with antidepressants and is unaffected by additional pharmacological inhibition of REM sleep.

  7. Retention over a Period of REM or non-REM Sleep.

    ERIC Educational Resources Information Center

    Tilley, Andrew J.

    1981-01-01

    Subjects, awaked, presented with a word list, and tested with arousal measures, were reawaked during REM or non-REM sleep and retested. Recall was facilitated by REM sleep. It was hypothesized that the high arousal level associated with REM sleep incidentally maintained the memory trace in a more retrievable form. (Author/SJL)

  8. Plugging meter

    DOEpatents

    Nagai, Akinori

    1979-01-01

    A plugging meter for automatically measuring the impurity concentration in a liquid metal is designed to have parallel passages including a cooling passage provided with a plugging orifice and with a flow meter, and a by-pass passage connected in series to a main passage having another flow meter, so that the plugging points may be obtained from the outputs of both flow meters. The plugging meter has a program signal generator, a flow-rate ratio setter and a comparator, and is adapted to change the temperature of the plugging orifice in accordance with a predetermined pattern or gradient, by means of a signal representative of the temperature of plugging orifice and a flow-rate ratio signal obtained from the outputs of both flow meters. This plugging meter affords an automatic and accurate measurement of a multi-plugging phenomenon taking place at the plugging orifice.

  9. Fission meter

    DOEpatents

    Rowland, Mark S [Alamo, CA; Snyderman, Neal J [Berkeley, CA

    2012-04-10

    A neutron detector system for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source.

  10. Biperiden administration during REM sleep deprivation diminished the frequency of REM sleep attempts.

    PubMed

    Salin-Pascual, R J; Grandos-Fuentes, D; Galicia-Polo, L; Nieves, E; Roehrs, T A; Roth, T

    1992-06-01

    Sixteen subjects were assigned to a group using either placebo or biperiden, with eight subjects in each group. Both groups were studied for one acclimatization night, one baseline night, four nights of rapid eye movement (REM) sleep deprivation and two recovery nights. All the subjects received either placebo or 4 mg biperiden 1 hour before sleep during the four nights of REM sleep deprivation. During the baseline and the recovery nights both groups received placebo capsules. The results showed that REM sleep time during the REM sleep deprivation was reduced by 70-75% below the baseline night in both groups. The number of attempts to enter REM sleep was significantly reduced by biperiden as compared to placebo for each of the four REM sleep deprivation nights. Because the total sleep time in the biperiden group was reduced, the number of REM sleep attempts was corrected by the total sleep time. The adjusted number of REM sleep attempts was also significantly reduced in the biperiden group. REM sleep latency showed a reduction in the placebo group, whereas in the biperiden group REM sleep latency was unchanged throughout the deprivation nights. In the recovery night REM sleep time was increased in both groups, with no differences between the groups. The REM sleep latency showed a reduction in the first recovery night in both groups that persisted through the second recovery night. The above findings support the role of biperiden as a REM sleep suppressive drug.

  11. Women's vaginal responses during REM Sleep.

    PubMed

    Abel, G G; Murphy, W D; Becker, J V; Bitar, A

    1979-01-01

    Eight female subjects underwent vaginal photoplethysmographic recordings while asleep. Results demonstrated consistent findings of decreases in relative blood volume and increases in relative pulse pressure within the vagina during REM periods. Thes vascular changes indicate that females undergo phasic shifts in vascular blood flow in the vagina during REM sleep, similar to the phasic shifts of blood flow in the male's penis during REM sleep.

  12. Intercomparison of radiation protection instrumentation in a pulsed neutron field

    NASA Astrophysics Data System (ADS)

    Caresana, M.; Denker, A.; Esposito, A.; Ferrarini, M.; Golnik, N.; Hohmann, E.; Leuschner, A.; Luszik-Bhadra, M.; Manessi, G.; Mayer, S.; Ott, K.; Röhrich, J.; Silari, M.; Trompier, F.; Volnhals, M.; Wielunski, M.

    2014-02-01

    In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68 MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60 MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instruments were placed in a reference position and irradiated with neutrons delivered in bursts of different intensity. The analysis of the instrument response as a function of the burst charge (the total electric charge of the protons in the burst shot onto the tungsten target) permitted to assess for each device the dose underestimation due to the time structure of the radiation field. The personal neutron dosemeters were exposed on a standard PMMA slab phantom and the response linearity was evaluated.

  13. Response of the Hanford Combination Neutron Dosimeter in plutonium environments

    SciTech Connect

    Endres, A.W.; Brackenbush, L.W.; Baumgartner, W.V.

    1996-02-01

    This report documents response characteristics and the development of dose algorithms for the Hanford Combination Neutron Dosimeter (HCNO) implemented on January 1, 1995. The HCND was accredited under the U.S. Department of Energy (DOE) Laboratory Accreditation Program (DOELAP) during 1994. The HCND employs two neutron dose components consisting of (1) an albedo thermoluminescent dosimeter (TLD), and (2) a track-etch dosimeter (TED). Response characteristics of these two dosimeter components were measured under the low-scatter conditions of the Hanford 318 Building Calibration Laboratory, and under the high-scatter conditions in the workplace at the Plutonium Finishing Plant (PFP). The majority of personnel neutron dose at Hanford (currently and historically) occurs at the PFP. National Institute of Standards and Technology (NIST) traceable sources were used to characterize dosimeter response in the laboratory. At the PFP, neutron spectra and dose-measuring instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters, were used to determine the neutron dose under several configurations from three different plutonium sources: (1) plutonium tetrafluoride, (2) plutonium metal, and (3) plutonium oxide. In addition, measurements were performed at many selected work locations. The HCNDs were included in all measurements. Comparison of dosimeter- and instrument-measured dose equivalents provided the data necessary to develop HCND dose algorithms and to assess the accuracy of estimated neutron dose under actual work conditions.

  14. Cross correlation calculations and neutron scattering analysis for a portable solid state neutron detection system

    NASA Astrophysics Data System (ADS)

    Saltos, Andrea

    In efforts to perform accurate dosimetry, Oakes et al. [Nucl. Intrum. Mehods. (2013)] introduced a new portable solid state neutron rem meter based on an adaptation of the Bonner sphere and the position sensitive long counter. The system utilizes high thermal efficiency neutron detectors to generate a linear combination of measurement signals that are used to estimate the incident neutron spectra. The inversion problem associated to deduce dose from the counts in individual detector elements is addressed by applying a cross-correlation method which allows estimation of dose with average errors less than 15%. In this work, an evaluation of the performance of this system was extended to take into account new correlation techniques and neutron scattering contribution. To test the effectiveness of correlations, the Distance correlation, Pearson Product-Moment correlation, and their weighted versions were performed between measured spatial detector responses obtained from nine different test spectra, and the spatial response of Library functions generated by MCNPX. Results indicate that there is no advantage of using the Distance Correlation over the Pearson Correlation, and that weighted versions of these correlations do not increase their performance in evaluating dose. Both correlations were proven to work well even at low integrated doses measured for short periods of time. To evaluate the contribution produced by room-return neutrons on the dosimeter response, MCNPX was used to simulate dosimeter responses for five isotropic neutron sources placed inside different sizes of rectangular concrete rooms. Results show that the contribution of scattered neutrons to the response of the dosimeter can be significant, so that for most cases the dose is over predicted with errors as large as 500%. A possible method to correct for the contribution of room-return neutrons is also assessed and can be used as a good initial estimate on how to approach the problem.

  15. Solar Meter

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The instrument pictured is an inexpensive solar meter which is finding wide acceptance among architects, engineers and others engaged in construction of solar energy facilities. It detects the amount of solar energy available at a building site, information necessary to design the most efficient type of solar system for a particular location. Incorporating technology developed by NASA's Lewis Research Center, the device is based upon the solar cell, which provides power for spacecraft by converting the sun's energy to electricity. The meter is produced by Dodge Products, Inc., Houston, Texas, a company formed to bring the technology to the commercial marketplace.

  16. Cells of a common developmental origin regulate REM/non-REM sleep and wakefulness in mice.

    PubMed

    Hayashi, Yu; Kashiwagi, Mitsuaki; Yasuda, Kosuke; Ando, Reiko; Kanuka, Mika; Sakai, Kazuya; Itohara, Shigeyoshi

    2015-11-20

    Mammalian sleep comprises rapid eye movement (REM) sleep and non-REM (NREM) sleep. To functionally isolate from the complex mixture of neurons populating the brainstem pons those involved in switching between REM and NREM sleep, we chemogenetically manipulated neurons of a specific embryonic cell lineage in mice. We identified excitatory glutamatergic neurons that inhibit REM sleep and promote NREM sleep. These neurons shared a common developmental origin with neurons promoting wakefulness; both derived from a pool of proneural hindbrain cells expressing Atoh1 at embryonic day 10.5. We also identified inhibitory γ-aminobutyric acid-releasing neurons that act downstream to inhibit REM sleep. Artificial reduction or prolongation of REM sleep in turn affected slow-wave activity during subsequent NREM sleep, implicating REM sleep in the regulation of NREM sleep.

  17. Saturation meter

    DOEpatents

    Gregurech, S.

    1984-08-01

    A saturation meter for use in a pressurized water reactor plant comprising a differential pressure transducer having a first and second pressure sensing means and an alarm. The alarm is connected to the transducer and is preset to activate at a level of saturation prior to the formation of a steam void in the reactor vessel.

  18. The Near Infrared robotic telescope REM

    NASA Astrophysics Data System (ADS)

    Goldoni, P.; Rem Team

    Observations of the prompt afterglow of Gamma Ray Burst events are unanimously considered of paramount importance for GRB science and related cosmology. Such observations at NIR wavelengths are even more promising allowing one to monitor high-z Ly-alfa absorbed bursts as well as events occurring in dusty star-forming regions. In these pages we present REM (Rapid Eye Mount), a fully robotized fast slewing telescope equipped with a high throughput NIR (Z, J, H, K) camera dedicated to detecting the prompt IR afterglow. REM can discover objects at extremely high redshift and trigger large telescopes to observe them. The REM telescope will simultaneously feed ROSS (REM Optical Slitless spectrograph) via a dichroic. ROSS will intensively monitor the prompt optical continuum of GRB afterglows. The synergy between REM-IR cam and ROSS makes REM a powerful observing tool for any kind of fast transient phenomena. The REM telescope is now installed in La Silla and its Science Verification Phase has been performed in Spring 2004. Preliminary results will be presented.

  19. Validation of the Innsbruck REM sleep behavior disorder inventory.

    PubMed

    Frauscher, Birgit; Ehrmann, Laura; Zamarian, Laura; Auer, Florentine; Mitterling, Thomas; Gabelia, David; Brandauer, Elisabeth; Delazer, Margarete; Poewe, Werner; Högl, Birgit

    2012-11-01

    A diagnosis of definite REM sleep behavior disorder requires both a positive history for REM sleep behavior disorder and polysomnographic demonstration of REM sleep without atonia. To improve and facilitate screening for REM sleep behavior disorder, there is a need for simple clinical tools with sufficient sensitivity and specificity for the identification of subjects with probable REM sleep behavior disorder. We developed a short REM sleep behavior disorder screening questionnaire with 7 REM sleep behavior disorder- and 2 non-REM sleep behavior disorder-specific control items and performed a validation study in 70 REM sleep behavior disorder subjects and 140 sleep disorder controls. Response patterns to all 7 REM sleep behavior disorder-specific items differed between REM sleep behavior disorder and non-REM sleep behavior disorder patients (all P < 0.05), whereas the 2 non-REM sleep behavior disorder-specific control items did not differentiate between REM sleep behavior disorder and non-REM sleep behavior disorder (all P > .05). In 5 of the 7 REM sleep behavior disorder-specific items, AUC was greater than 0.700. These 5 items were included in the Innsbruck REM sleep behavior disorder inventory. In this questionnaire, a cutoff of 0.25 (number of positive symptoms divided by number of answered questions) had a sensitivity of 0.914 and a specificity of 0.857 for both idiopathic and Parkinson's-related REM sleep behavior disorder (AUC, 0.886). The Innsbruck REM sleep behavior disorder inventory is a promising, easy-to-use, short screening tool for REM sleep behavior disorder with excellent sensitivity and specificity for both idiopathic and Parkinson's-related REM sleep behavior disorder.

  20. Memory sources of REM and NREM dreams.

    PubMed

    Cavallero, C; Foulkes, D; Hollifield, M; Terry, R

    1990-10-01

    Sixteen male volunteers slept 4 nonconsecutive nights each in a sleep laboratory. They were awakened for one dream report per night. Awakenings were made, in counterbalanced order, from early-night and late-night rapid-eye movement (REM) and non-REM (NREM) sleep. Following dream reporting, subjects were asked to identify memory sources of their dream imagery. Two independent judges reliably rated mentation reports for temporal units and categorized memory sources as autobiographical episodes, abstract self-references, or semantic knowledge. We replicated earlier findings that semantic knowledge is more frequently mentioned as a dream source for REM than for NREM reports. However, with controls for length of reports, the REM-NREM difference disappeared, indicating that the stage difference in memory sources was not independent of stage difference in report lengths. There was a significant effect of time of night on source class, but only in REM sleep: Both without and with controls for report length, more semantic sources were cited for late than for early REM dreams.

  1. REMS Wind Sensor Preliminary Results

    NASA Astrophysics Data System (ADS)

    De La Torre Juarez, M.; Gomez-Elvira, J.; Navarro, S.; Marin, M.; Torres, J.; Rafkin, S. C.; Newman, C. E.; Pla-García, J.

    2015-12-01

    The REMS instrument is part of the Mars Science Laboratory payload. It is a sensor suite distributed over several parts of the rover. The wind sensor, which is composed of two booms equipped with a set of hot plate anemometers, is installed on the Rover Sensing Mast (RSM). During landing most of the hot plates of one boom were damaged, most likely by the pebbles lifted by the Sky Crane thruster. The loss of one wind boom necessitated a full review of the data processing strategy. Different algorithms have been tested on the readings of the first Mars year, and these results are now archived in the Planetary Data System (PDS), The presentation will include a description of the data processing methods and of the resulting products, including the typical evolution of wind speed and direction session-by-session, hour-by-hour and other kinds of statistics . A review of the wind readings over the first Mars year will also be presented.

  2. Recent Re-Measurement of Neutron and Gamma-Ray Spectra 1080 Meters from the APRD (Army Pulse Radiation Division) Critical Facility,

    DTIC Science & Technology

    1984-01-01

    spectres d𔄀missions neutroniques et de rayons gamma. On a compar6 les risultats de ces mesures A plusieurs calculs rcents effectu~s par d’autres...les neutrons et le- rayons gamma; on observe toutefois d’importantes differences spectrales. A - faible altitude, les spectres neutroniques son i6g...measurements were performed by both groups, using a variety of tissue-equivalent ion-chambers, Geiger-M(.ller counters and sulphur activation (n,p). In 1980

  3. Neutron spectra and dose-rate measurements around a transport cask for spent reactor fuel

    NASA Astrophysics Data System (ADS)

    Rimpler, Arndt

    1997-02-01

    A storage facility with a capacity of 420 containers is available for the interim storage of spent fuel from power reactors at the village of Gorleben in Germany. During transportation and storage of spent fuel casks radiation exposure of the personnel is dominated by neutrons. The routine control of the dose rate limits according to the transport regulations and the licence of the storage facility is performed with conventional neutron survey meters. These monitors, calibrated for fast neutrons at radionuclide neutron sources, usually overestimate the real dose rate in unknown neutron fields. In this paper, a series of measurements with several monitoring instruments near a transport cask of the CASTOR type is presented. The results are compared with reference data for the does equivalents calculated from the measured fluence spectra using a Bonner multisphere spectrometer. Besides reliable information about neutron spectra and dose rates at the container, it was found that some of the rem counters overestimate the true dose rate by a factor of 2 or more.

  4. Characterization of neutron reference fields at US Department of Energy calibration fields.

    PubMed

    Olsher, R H; McLean, T D; Mallett, M W; Seagraves, D T; Gadd, M S; Markham, Robin L; Murphy, R O; Devine, R T

    2007-01-01

    The Health Physics Measurements Group at the Los Alamos National Laboratory (LANL) has initiated a study of neutron reference fields at selected US Department of Energy (DOE) calibration facilities. To date, field characterisation has been completed at five facilities. These fields are traceable to the National Institute for Standards and Technology (NIST) through either a primary calibration of the source emission rate or through the use of a secondary standard. However, neutron spectral variation is caused by factors such as room return, scatter from positioning tables and fixtures, source anisotropy and spectral degradation due to source rabbits and guide tubes. Perturbations from the ideal isotropic point source field may impact the accuracy of instrument calibrations. In particular, the thermal neutron component of the spectrum, while contributing only a small fraction of the conventionally true dose, can contribute a significant fraction of a dosemeter's response with the result that the calibration becomes facility-specific. A protocol has been developed to characterise neutron fields that relies primarily on spectral measurements with the Bubble Technology Industries (BTI) rotating neutron spectrometer (ROSPEC) and the LANL Bonner sphere spectrometer. The ROSPEC measurements were supplemented at several sites by the BTI Simple Scintillation Spectrometer probe, which is designed to extend the ROSPEC upper energy range from 5 to 15 MeV. In addition, measurements were performed with several rem meters and neutron dosemeters. Detailed simulations were performed using the LANL MCNPX Monte Carlo code to calculate the magnitude of source anisotropy and scatter factors.

  5. Impact of the Revised 10 CFR 835 on the Neutron Dose Rates at LLNL

    SciTech Connect

    Radev, R

    2009-01-13

    In June 2007, 10 CFR 835 [1] was revised to include new radiation weighting factors for neutrons, updated dosimetric models, and dose terms consistent with the newer ICRP recommendations. A significant aspect of the revised 10 CFR 835 is the adoption of the recommendations outlined in ICRP-60 [2]. The recommended new quantities demand a review of much of the basic data used in protection against exposure to sources of ionizing radiation. The International Commission on Radiation Units and Measurements has defined a number of quantities for use in personnel and area monitoring [3,4,5] including the ambient dose equivalent H*(d) to be used for area monitoring and instrument calibrations. These quantities are used in ICRP-60 and ICRP-74. This report deals only with the changes in the ambient dose equivalent and ambient dose rate equivalent for neutrons as a result of the implementation of the revised 10 CFR 835. In the report, the terms neutron dose and neutron dose rate will be used for convenience for ambient neutron dose and ambient neutron dose rate unless otherwise stated. This report provides a qualitative and quantitative estimate of how much the neutron dose rates at LLNL will change with the implementation of the revised 10 CFR 835. Neutron spectra and dose rates from selected locations at the LLNL were measured with a high resolution spectroscopic neutron dose rate system (ROSPEC) as well as with a standard neutron rem meter (a.k.a., a remball). The spectra obtained at these locations compare well with the spectra from the Radiation Calibration Laboratory's (RCL) bare californium source that is currently used to calibrate neutron dose rate instruments. The measurements obtained from the high resolution neutron spectrometer and dose meter ROSPEC and the NRD dose meter compare within the range of {+-}25%. When the new radiation weighting factors are adopted with the implementation of the revised 10 CFR 835, the measured dose rates will increase by up to 22

  6. REM sleep disorder following general anesthesia in rats.

    PubMed

    Lazic, Katarina; Petrovic, Jelena; Ciric, Jelena; Kalauzi, Aleksandar; Saponjic, Jasna

    2017-01-01

    Postoperative sleep disorders, particularly the REM sleep disorder, may have a significant deleterious impact on postoperative outcomes and may contribute to the genesis of certain delayed postoperative complications. We have followed the effect of distinct anesthesia regimens (ketamine/diazepam vs. pentobarbital) over 6days following the induction of a stable anesthetized state in adult male Wistar rats, chronically instrumented for sleep recording. In order to compare the effect of both anesthetics in the physiological controls vs. the rats with impaired pedunculopontine tegmental nucleus (PPT) cholinergic innervation, during the operative procedure for the implantation of EEG and EMG electrodes, the bilateral PPT lesion was conducted using ibotenic acid (IBO). We have followed in particular post-anesthesia REM sleep. Our results show the distinct EEG microstructure of the motor cortex during the different stable anesthetized states, and their distinct impact on post-anesthesia REM sleep. In contrast to pentobarbital anesthesia, the ketamine/diazepam anesthesia potentiated the long-lasting post-anesthesia REM statewith higher muscle tone (REM1) vs. REM state with atonia (REM2). Whereas both anesthesias prolonged the post-anesthesia REM sleep duration, the long-term prolongation of the REM1 state was demonstrated only after the ketamine/diazepam anesthesia, first due to the increased number of REM1 episodes, and then due to the prolonged REM1 episodes duration. On the other hand, whereas both anesthetic regimens abolished the prolonged post-anesthesia REM/REM1 sleep and the EEG microstructure disorder during REM sleep, only the pentobarbital abolished the increased NREM/REM/NREM transitions, caused by the PPT lesion. In addition, in the PPT lesioned rats, the ketamine/diazepam anesthesia decreased the Wake/NREM/Wake transitions while the pentobarbital anesthesia decreased the Wake/REM/Wake transitions. Our present study suggests pentobarbital anesthesia as being

  7. REM Sleep Behavioral Events and Dreaming

    PubMed Central

    Muntean, Maria-Lucia; Trenkwalder, Claudia; Walters, Arthur S.; Mollenhauer, Brit; Sixel-Döring, Friederike

    2015-01-01

    Study Objectives: To clarify whether motor behaviors and/ or vocalizations during REM sleep, which do not yet fulfill diagnostic criteria for REM sleep behavior disorder (RBD) and were defined as REM sleep behavioral events (RBEs), correspond to dream enactments. Methods: 13 subjects (10 patients with Parkinson disease [PD] and 3 healthy controls) originally identified with RBE in a prospective study (DeNoPa cohort) were reinvestigated 2 years later with 2 nights of video-supported polysomnography (vPSG). The first night was used for sleep parameter analysis. During the 2nd night, subjects were awakened and questioned for dream recall and dream content when purposeful motor behaviors and/or vocalizations became evident during REM sleep. REM sleep without atonia (RWA) was analyzed on chin EMG and the cutoff set at 18.2% as specific for RBD. Results: At the time of this investigation 9 of 13 subjects with previous RBE were identified with RBD based upon clinical and EMG criteria. All recalled vivid dreams, and 7 subjects were able to describe dream content in detail. Four of 13 subjects with RBE showed RWA values below cutoff values for RBD. Three of these 4 subjects recalled having non-threatening dreams, and 2 (of these 3) were able to describe these dreams in detail. Conclusion: RBE with RWA below the RBD defining criteria correlate to dreaming in this selected cohort. There is evidence that RBEs are a precursor to RBD. Citation: Muntean ML, Trenkwalder C, Walters AS, Mollenhauer B, Sixel-Döring F. REM sleep behavioral events and dreaming. J Clin Sleep Med 2015;11(5):537–541. PMID:25665694

  8. LUPIN, a new instrument for pulsed neutron fields

    NASA Astrophysics Data System (ADS)

    Caresana, M.; Ferrarini, M.; Manessi, G. P.; Silari, M.; Varoli, V.

    2013-06-01

    A number of studies focused in the last decades on the development of survey meters to be used in pulsed radiation fields. This is a topic attracting widespread interest for applications such as radiation protection and beam diagnostics in accelerators. This paper describes a new instrument specifically conceived for applications in pulsed neutron fields (PNF). The detector, called LUPIN, is a rem counter type instrument consisting of a 3He proportional counter placed inside a spherical moderator. It works in current mode with a front-end electronics consisting of a current-voltage logarithmic amplifier, whose output signal is acquired with an ADC and processed on a PC. This alternative signal processing allows the instrument to be used in PNF without being affected by saturation effects. Moreover, it has a measurement capability ranging over many orders of burst intensity. Despite the fact that it works in current mode, it can measure a single neutron interaction. The LUPIN was first calibrated in CERN's calibration laboratory with a PuBe source. Measurements were carried out under various experimental conditions at the Helmholtz-Zentrum in Berlin, in the stray field at various locations of the CERN Proton Synchrotron complex and around a radiotherapy linear accelerator at the S. Raffaele hospital in Milan. The detector can withstand single bursts with values of H*(10) up to 16 nSv/burst without showing any saturation effect. It efficiently works in pulsed stray fields, where a conventional rem-counter underestimates by a factor of 2. It is also able to reject the very intense and pulsed photon contribution that often accompanies the neutron field with good reliability.

  9. Portable neutron spectrometer and dosimeter

    DOEpatents

    Waechter, D.A.; Erkkila, B.H.; Vasilik, D.G.

    The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

  10. Portable neutron spectrometer and dosimeter

    DOEpatents

    Waechter, David A.; Erkkila, Bruce H.; Vasilik, Dennis G.

    1985-01-01

    The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

  11. Processing of memories and knowledge in REM and NREM dreams.

    PubMed

    Foulkes, D; Bradley, L; Cavellero, C; Hollifield, M

    1989-04-01

    Over 4 nights, 16 young-adult males each reported 2 REM and 2 nonREM dreams. They then identified possible sources of dream imagery in their waking memory and/or knowledge. A judge, naive as to conditions of data collection, reliably judged the closeness of correspondence of dream event to identified source. Correspondence was lower for REM than for nonREM reports and for longer than for shorter reports from either stage.

  12. [The Function of REM Sleep: Implications from Transgenic Mouse Models].

    PubMed

    Kashiwagi, Mitsuaki; Hayashi, Yu

    2016-10-01

    Our sleep is composed of rapid eye movement (REM) sleep and non-REM (NREM) sleep. REM sleep is the major source of dreams, whereas synchronous cortical oscillations, called slow waves, are observed during NREM sleep. Both stages are unique to certain vertebrate species, and therefore, REM and NREM sleep are thought to be involved in higher-order brain functions. While several studies have revealed the importance of NREM sleep in growth hormone secretion, memory consolidation and brain metabolite clearance, the functions of REM sleep are currently almost totally unknown. REM sleep functions cannot be easily indicated from classical REM sleep deprivation experiments, where animals are forced to wake up whenever they enter REM sleep, because such experiments produce extreme stress due to the stimuli and because REM sleep is under strong homeostatic regulation. To overcome these issues, we developed a novel transgenic mouse model in which REM sleep can be manipulated. Using these mice, we found that REM sleep enhances slow wave activity during the subsequent NREM sleep. Slow wave activity is known to contribute to memory consolidation and synaptic plasticity. Thus, REM sleep might be involved in higher-order brain functions through its role in enhancing slow wave activity.

  13. REM sleep rescues learning from interference.

    PubMed

    McDevitt, Elizabeth A; Duggan, Katherine A; Mednick, Sara C

    2015-07-01

    Classical human memory studies investigating the acquisition of temporally-linked events have found that the memories for two events will interfere with each other and cause forgetting (i.e., interference; Wixted, 2004). Importantly, sleep helps consolidate memories and protect them from subsequent interference (Ellenbogen, Hulbert, Stickgold, Dinges, & Thompson-Schill, 2006). We asked whether sleep can also repair memories that have already been damaged by interference. Using a perceptual learning paradigm, we induced interference either before or after a consolidation period. We varied brain states during consolidation by comparing active wake, quiet wake, and naps with either non-rapid eye movement sleep (NREM), or both NREM and REM sleep. When interference occurred after consolidation, sleep and wake both produced learning. However, interference prior to consolidation impaired memory, with retroactive interference showing more disruption than proactive interference. Sleep rescued learning damaged by interference. Critically, only naps that contained REM sleep were able to rescue learning that was highly disrupted by retroactive interference. Furthermore, the magnitude of rescued learning was correlated with the amount of REM sleep. We demonstrate the first evidence of a process by which the brain can rescue and consolidate memories damaged by interference, and that this process requires REM sleep. We explain these results within a theoretical model that considers how interference during encoding interacts with consolidation processes to predict which memories are retained or lost.

  14. REM sleep rescues learning from interference

    PubMed Central

    McDevitt, Elizabeth A.; Duggan, Katherine A.; Mednick, Sara C.

    2015-01-01

    Classical human memory studies investigating the acquisition of temporally-linked events have found that the memories for two events will interfere with each other and cause forgetting (i.e., interference; Wixted, 2004). Importantly, sleep helps consolidate memories and protect them from subsequent interference (Ellenbogen, Hulbert, Stickgold, Dinges, & Thompson-Schill, 2006). We asked whether sleep can also repair memories that have already been damaged by interference. Using a perceptual learning paradigm, we induced interference either before or after a consolidation period. We varied brain states during consolidation by comparing active wake, quiet wake, and naps with either non-rapid eye movement sleep (NREM), or both NREM and REM sleep. When interference occurred after consolidation, sleep and wake both produced learning. However, interference prior to consolidation impaired memory, with retroactive interference showing more disruption than proactive interference. Sleep rescued learning damaged by interference. Critically, only naps that contained REM sleep were able to rescue learning that was highly disrupted by retroactive interference. Furthermore, the magnitude of rescued learning was correlated with the amount of REM sleep. We demonstrate the first evidence of a process by which the brain can rescue and consolidate memories damaged by interference, and that this process requires REM sleep. We explain these results within a theoretical model that considers how interference during encoding interacts with consolidation processes to predict which memories are retained or lost. PMID:25498222

  15. Posttraining Increases in REM Sleep Intensity Implicate REM Sleep in Memory Processing and Provide a Biological Marker of Learning Potential

    ERIC Educational Resources Information Center

    Nader, Rebecca S.; Smith, Carlyle T.; Nixon, Margaret R.

    2004-01-01

    Posttraining rapid eye movement (REM) sleep has been reported to be important for efficient memory consolidation. The present results demonstrate increases in the intensity of REM sleep during the night of sleep following cognitive procedural/implicit task acquisition. These REM increases manifest as increases in total number of rapid eye…

  16. Parkinsonian tremor loses its alternating aspect during non-REM sleep and is inhibited by REM sleep.

    PubMed Central

    Askenasy, J J; Yahr, M D

    1990-01-01

    Non-REM sleep transforms the waking alternating Parkinsonian tremor into subclinical repetitive muscle contractions whose amplitude and duration decrease as non-REM sleep progresses from stages I to IV. During REM sleep Parkinsonian tremor disappears while the isolated muscle events increase significantly. PMID:2246656

  17. Control of REM sleep by ventral medulla GABAergic neurons.

    PubMed

    Weber, Franz; Chung, Shinjae; Beier, Kevin T; Xu, Min; Luo, Liqun; Dan, Yang

    2015-10-15

    Rapid eye movement (REM) sleep is a distinct brain state characterized by activated electroencephalogram and complete skeletal muscle paralysis, and is associated with vivid dreams. Transection studies by Jouvet first demonstrated that the brainstem is both necessary and sufficient for REM sleep generation, and the neural circuits in the pons have since been studied extensively. The medulla also contains neurons that are active during REM sleep, but whether they play a causal role in REM sleep generation remains unclear. Here we show that a GABAergic (γ-aminobutyric-acid-releasing) pathway originating from the ventral medulla powerfully promotes REM sleep in mice. Optogenetic activation of ventral medulla GABAergic neurons rapidly and reliably initiated REM sleep episodes and prolonged their durations, whereas inactivating these neurons had the opposite effects. Optrode recordings from channelrhodopsin-2-tagged ventral medulla GABAergic neurons showed that they were most active during REM sleep (REMmax), and during wakefulness they were preferentially active during eating and grooming. Furthermore, dual retrograde tracing showed that the rostral projections to the pons and midbrain and caudal projections to the spinal cord originate from separate ventral medulla neuron populations. Activating the rostral GABAergic projections was sufficient for both the induction and maintenance of REM sleep, which are probably mediated in part by inhibition of REM-suppressing GABAergic neurons in the ventrolateral periaqueductal grey. These results identify a key component of the pontomedullary network controlling REM sleep. The capability to induce REM sleep on command may offer a powerful tool for investigating its functions.

  18. Increased voluntary alcohol drinking concurrent with REM-sleep deprivation.

    PubMed

    Aalto, J; Kiianmaa, K

    1984-01-01

    The alcohol intake of twenty adult Long-Evans male rats was recorded before, during and after rapid eye movement sleep (REM) deprivation produced with the flowerpot technique modified by using a cuff pedestal and an electrified grid floor instead of water. The alcohol intake reached a steady level of 2.8 g/kg/day in the 3 weeks before REM deprivation. During seven REM-sleep deprivation days the alcohol intake was significantly elevated, finally increasing to 3.7 g/kg/day. A rebound decrease in alcohol drinking was then observed during the "REM-rebound" phase immediately after the termination of REM-sleep deprivation. The results suggest a possible vicious circle of REM-sleep deprivation increasing alcohol drinking and alcohol intake causing REM-sleep deprivation.

  19. Arousal thresholds during human tonic and phasic REM sleep.

    PubMed

    Ermis, Ummehan; Krakow, Karsten; Voss, Ursula

    2010-09-01

    The goal of the present study was to investigate arousal thresholds (ATs) in tonic and phasic episodes of rapid eye movement (REM) sleep, and to compare the frequency spectrum of these sub-states of REM to non-REM (NREM) stages of sleep. We found the two REM stages to differ with regard to behavioural responses to external acoustic stimuli. The AT in tonic REM was indifferent from that in sleep stage 2, and ATs in phasic REM were similar to those in slow-wave sleep (stage 4). NREM and REM stages of similar behavioural thresholds were distinctly different with regard to their frequency pattern. These data provide further evidence that REM sleep should not be regarded a uniform state. Regarding electroencephalogram frequency spectra, we found that the two REM stages were more similar to each other than to NREM stages with similar responsivity. Ocular activity such as ponto-geniculo-occipital-like waves and microsaccades are discussed as likely modulators of behavioural responsiveness and cortical processing of auditory information in the two REM sub-states.

  20. REM sleep dysregulation in depression: state of the art.

    PubMed

    Palagini, Laura; Baglioni, Chiara; Ciapparelli, Antonio; Gemignani, Angelo; Riemann, Dieter

    2013-10-01

    Disturbances of sleep are typical for most depressed patients and belong to the core symptoms of the disorder. Since the 1960s polysomnographic sleep research has demonstrated that besides disturbances of sleep continuity, depression is associated with altered sleep architecture, i.e., a decrease in slow wave sleep (SWS) production and disturbed rapid eye movement (REM) sleep regulation. Shortened REM latency (i.e., the interval between sleep onset and the occurrence of the first REM period), increased REM sleep duration and increased REM density (i.e., the frequency of rapid eye movements per REM period) have been considered as biological markers of depression which might predict relapse and recurrence. High risk studies including healthy relatives of patients with depression demonstrate that REM sleep alterations may precede the clinical expression of depression and may thus be useful in identifying subjects at high risk for the illness. Several models have been developed to explain REM sleep abnormalities in depression, like the cholinergic-aminergic imbalance model or chronobiologically inspired theories, which are reviewed in this overview. Moreover, REM sleep alterations have been recently considered not only as biological "scars" but as true endophenotypes of depression. This review discusses the genetic, neurochemical and neurobiological factors that have been implicated to play a role in the complex relationships between REM sleep and depression. We hypothesize on the one hand that REM sleep dysregulation in depression may be linked to a genetic predisposition/vulnerability to develop the illness; on the other hand it is conceivable that REM sleep disinhibition in itself is a part of a maladaptive stress reaction with increased allostatic load. We also discuss whether the REM sleep changes in depression may contribute themselves to the development of central symptoms of depression such as cognitive distortions including negative self-esteem and the

  1. Human REM sleep: influence on feeding behaviour, with clinical implications.

    PubMed

    Horne, James A

    2015-08-01

    Rapid eye movement (REM) sleep shares many underlying mechanisms with wakefulness, to a much greater extent than does non-REM, especially those relating to feeding behaviours, appetite, curiosity, exploratory (locomotor) activities, as well as aspects of emotions, particularly 'fear extinction'. REM is most evident in infancy, thereafter declining in what seems to be a dispensable manner that largely reciprocates increasing wakefulness. However, human adults retain more REM than do other mammals, where for us it is most abundant during our usual final REM period (fREMP) of the night, nearing wakefulness. The case is made that our REM is unusual, and that (i) fREMP retains this 'dispensability', acting as a proxy for wakefulness, able to be forfeited (without REM rebound) and substituted by physical activity (locomotion) when pressures of wakefulness increase; (ii) REM's atonia (inhibited motor output) may be a proxy for this locomotion; (iii) our nocturnal sleep typically develops into a physiological fast, especially during fREMP, which is also an appetite suppressant; (iv) REM may have 'anti-obesity' properties, and that the loss of fREMP may well enhance appetite and contribute to weight gain ('overeating') in habitually short sleepers; (v) as we also select foods for their hedonic (emotional) values, REM may be integral to developing food preferences and dislikes; and (vii) REM seems to have wider influences in regulating energy balance in terms of exercise 'substitution' and energy (body heat) retention. Avenues for further research are proposed, linking REM with feeding behaviours, including eating disorders, and effects of REM-suppressant medications.

  2. Breathing during REM and non-REM sleep: correlated versus uncorrelated behaviour

    NASA Astrophysics Data System (ADS)

    Kantelhardt, Jan W.; Penzel, Thomas; Rostig, Sven; Becker, Heinrich F.; Havlin, Shlomo; Bunde, Armin

    2003-03-01

    Healthy sleep can be characterized by several stages: deep sleep, light sleep, and REM sleep. Here we show that these sleep stages lead to different autonomic regulation of breathing. Using the detrended fluctuation analysis up to the fourth order we find that breath-to-breath intervals and breath volumes separated by several breaths are long-range correlated during the REM stages and during wake states. In contrast, in the non-REM stages (deep sleep and light sleep), long-range correlations are absent. This behaviour is very similar to the correlation behaviour of the heart rate during the night and may be related to the phase synchronization between heartbeat and breathing found recently. We speculate that the differences are caused by different cortically influenced control of the autonomic nervous system.

  3. Intrinsic dreams are not produced without REM sleep mechanisms: evidence through elicitation of sleep onset REM periods.

    PubMed

    Takeuchi, T; Miyasita, A; Inugami, M; Yamamoto, Y

    2001-03-01

    The hypothesis that there is a strict relationship between dreams and a specific rapid eye movement (REM) sleep mechanism is controversial. Many researchers have recently denied this relationship, yet none of their studies have simultaneously controlled both sleep length and depth prior to non-REM (NREM) and REM sleep awakenings, due to the natural rigid order of the NREM--REM sleep cycle. The failure to control sleep length and depth prior to arousal has confounded interpretations of the REM-dreams relationship. We have hypothesised that different physiological mechanisms underlie dreaming during REM and NREM sleep, based on recent findings concerning the specificity of REM sleep for cognitive function. Using the Sleep Interruption Technique, we elicited sleep onset REM periods (SOREMP) from 13 normal subjects to collect SOREMP and sleep onset NREM (NREMP) dreams without the confounds described above. Regression analyses showed that SOREMP dream occurrences were significantly related to the amount of REM sleep, while NREMP dream occurrences were related to arousals from NREM sleep. Dream properties evaluated using the Dream Property Scale showed qualitative differences between SOREMP and NREMP dream reports. These results support our hypothesis and we have concluded that although 'dreaming' may occur during both REM and NREM periods as previous researchers have suggested, the dreams obtained from these distinct periods differ significantly in their quantitative and qualitative aspects and are likely to be produced by different mechanisms.

  4. Control of REM Sleep by Ventral Medulla GABAergic Neurons

    PubMed Central

    Weber, Franz; Chung, Shinjae; Beier, Kevin T.; Luo, Liqun; Dan, Yang

    2015-01-01

    Rapid eye movement (REM) sleep is a distinct brain state characterized by activated electroencephalogram (EEG) and complete skeletal muscle paralysis, and it is associated with vivid dreams1-3. Transection studies by Jouvet first demonstrated that the brainstem is both necessary and sufficient for REM sleep generation2, and the neural circuits in the pons have since been studied extensively4-8. The medulla also contains neurons that are active during REM sleep9-13, but whether they play a causal role in REM sleep generation remains unclear. Here we show that a GABAergic pathway originating from the ventral medulla (vM) powerfully promotes REM sleep. Optogenetic activation of vM GABAergic neurons rapidly and reliably initiated REM sleep episodes and prolonged their durations, whereas inactivating these neurons had the opposite effects. Optrode recordings from channelrhodopsin 2 (ChR2)-tagged vM GABAergic neurons showed that they were most active during REM sleep (REM-max), and during wakefulness they were preferentially active during eating and grooming. Furthermore, dual retrograde tracing showed that the rostral projections to the pons and midbrain and caudal projections to the spinal cord originate from separate vM neuron populations. Activating the rostral GABAergic projections was sufficient for both the induction and maintenance of REM sleep, which are likely mediated in part by inhibition of REM-suppressing GABAergic neurons in the ventrolateral periaqueductal gray (vlPAG). These results identify a key component of the pontomedullary network controlling REM sleep. The capability to induce REM sleep on command may offer a powerful tool for investigating its functions. PMID:26444238

  5. Selective REM Sleep Deprivation Improves Expectation-Related Placebo Analgesia.

    PubMed

    Chouchou, Florian; Chauny, Jean-Marc; Rainville, Pierre; Lavigne, Gilles J

    2015-01-01

    The placebo effect is a neurobiological and psychophysiological process known to influence perceived pain relief. Optimization of placebo analgesia may contribute to the clinical efficacy and effectiveness of medication for acute and chronic pain management. We know that the placebo effect operates through two main mechanisms, expectations and learning, which is also influenced by sleep. Moreover, a recent study suggested that rapid eye movement (REM) sleep is associated with modulation of expectation-mediated placebo analgesia. We examined placebo analgesia following pharmacological REM sleep deprivation and we tested the hypothesis that relief expectations and placebo analgesia would be improved by experimental REM sleep deprivation in healthy volunteers. Following an adaptive night in a sleep laboratory, 26 healthy volunteers underwent classical experimental placebo analgesic conditioning in the evening combined with pharmacological REM sleep deprivation (clonidine: 13 volunteers or inert control pill: 13 volunteers). Medication was administered in a double-blind manner at bedtime, and placebo analgesia was tested in the morning. Results revealed that 1) placebo analgesia improved with REM sleep deprivation; 2) pain relief expectations did not differ between REM sleep deprivation and control groups; and 3) REM sleep moderated the relationship between pain relief expectations and placebo analgesia. These results support the putative role of REM sleep in modulating placebo analgesia. The mechanisms involved in these improvements in placebo analgesia and pain relief following selective REM sleep deprivation should be further investigated.

  6. Selective REM Sleep Deprivation Improves Expectation-Related Placebo Analgesia

    PubMed Central

    Chouchou, Florian; Chauny, Jean-Marc; Rainville, Pierre; Lavigne, Gilles J.

    2015-01-01

    The placebo effect is a neurobiological and psychophysiological process known to influence perceived pain relief. Optimization of placebo analgesia may contribute to the clinical efficacy and effectiveness of medication for acute and chronic pain management. We know that the placebo effect operates through two main mechanisms, expectations and learning, which is also influenced by sleep. Moreover, a recent study suggested that rapid eye movement (REM) sleep is associated with modulation of expectation-mediated placebo analgesia. We examined placebo analgesia following pharmacological REM sleep deprivation and we tested the hypothesis that relief expectations and placebo analgesia would be improved by experimental REM sleep deprivation in healthy volunteers. Following an adaptive night in a sleep laboratory, 26 healthy volunteers underwent classical experimental placebo analgesic conditioning in the evening combined with pharmacological REM sleep deprivation (clonidine: 13 volunteers or inert control pill: 13 volunteers). Medication was administered in a double-blind manner at bedtime, and placebo analgesia was tested in the morning. Results revealed that 1) placebo analgesia improved with REM sleep deprivation; 2) pain relief expectations did not differ between REM sleep deprivation and control groups; and 3) REM sleep moderated the relationship between pain relief expectations and placebo analgesia. These results support the putative role of REM sleep in modulating placebo analgesia. The mechanisms involved in these improvements in placebo analgesia and pain relief following selective REM sleep deprivation should be further investigated. PMID:26678391

  7. Optical and near-infrared photometric monitoring of the transient X-ray binary A0538-66 with REM

    NASA Astrophysics Data System (ADS)

    Ducci, L.; Covino, S.; Doroshenko, V.; Mereghetti, S.; Santangelo, A.; Sasaki, M.

    2016-11-01

    The transient Be/X-ray binary A0538-66 shows peculiar X-ray and optical variability. Despite numerous studies, the intrinsic properties underlying its anomalous behaviour remain poorly understood. Since September 2014 we have conducted the first quasi-simultaneous, optical and near-infrared photometric monitoring of A0538-66 in seven filters with the Rapid Eye Mount (REM) telescope to understand the properties of this binary system. We found that the REM light curves show fast flares lasting one or two days that repeat almost regularly every 16.6 d, which is the orbital period of the neutron star. If the optical flares are powered by X-ray outbursts through photon reprocessing, the REM light curves indicate that A0538-66 is still active in X-rays; bright X-ray flares (Lx ≳ 1037 erg s-1) could be observable during the periastron passages. The REM light curves show a long-term variability that is especially pronounced in the g-band and decreases with increasing wavelength until it no longer appears in the near-infrared light curves. In addition, A0538-66 is fainter with respect to previous optical observations, and this is likely because of the higher absorption of the stellar radiation of a denser circumstellar disc. On the basis of the current models, we interpret these observational results with a circumstellar disc around the Be star observed nearly edge-on during a partial depletion phase. The REM light curves also show short-term variability on timescales of 1 day, which is possibly indicative of perturbations in the density distribution of the circumstellar disc caused by the tidal interaction with the neutron star.

  8. Quantification of Electromyographic Activity During REM Sleep in Multiple Muscles in REM Sleep Behavior Disorder

    PubMed Central

    Frauscher, Birgit; Iranzo, Alex; Högl, Birgit; Casanova-Molla, Jordi; Salamero, Manel; Gschliesser, Viola; Tolosa, Eduardo; Poewe, Werner; Santamaria, Joan

    2008-01-01

    Study Objectives: The aim of our study was to determine which muscle or combination of muscles (either axial or limb muscles, lower or upper limb muscles, or proximal or distal limb muscles) provides the highest rates of rapid eye movement (REM) sleep phasic electromyographic (EMG) activity seen in patients with REM sleep behavior disorder (RBD). Setting: Two university hospital sleep disorders centers. Participants: Seventeen patients with idiopathic RBD (n = 8) and RBD secondary to Parkinson disease (n = 9). Interventions: Not applicable. Measurements and Results: Patients underwent polysomnography, including EMG recording of 13 different muscles. Phasic EMG activity in REM sleep was quantified for each muscle separately. A mean of 1459.6 ± 613.8 three-second REM sleep mini-epochs were scored per patient. Mean percentages of phasic EMG activity were mentalis (42 ± 19), flexor digitorum superficialis (29 ± 13), extensor digitorum brevis (23 ± 12), abductor pollicis brevis (22 ± 11), sternocleidomastoid (22 ± 12), deltoid (19 ± 11), biceps brachii (19 ± 11), gastrocnemius (18 ± 9), tibialis anterior (right, 17 ± 12; left, 16 ± 10), rectus femoris (left, 11 ± 6; right, 9 ± 6), and thoraco-lumbar paraspinal muscles (6 ± 5). The mentalis muscle provided significantly higher rates of excessive phasic EMG activity than all other muscles but only detected 55% of all the mini-epochs with phasic EMG activity. Simultaneous recording of the mentalis, flexor digitorum superficialis, and extensor digitorum brevis muscles detected 82% of all mini-epochs containing phasic EMG activity. This combination provided higher rates of EMG activity than any other 3-muscle combination. Excessive phasic EMG activity was more frequent in distal than in proximal muscles, both in upper and lower limbs. Conclusion: Simultaneous recording of the mentalis, flexor digitorum superficialis, and extensor digitorum brevis muscles provided the highest rates of REM sleep phasic EMG

  9. A Matter of Meter

    ERIC Educational Resources Information Center

    Harrison, David L.

    2006-01-01

    Writing verse is a learning experience. Arranging words, sounds and syllables can turn everyday language into metered language (language that can be measured), and metered language is the definition of verse. This article discusses the use of meter in helping students establish sets of syllables and lines that can be counted, enabling them to…

  10. Ischemic stroke selectively inhibits REM sleep of rats.

    PubMed

    Ahmed, Samreen; Meng, He; Liu, Tiecheng; Sutton, Blair C; Opp, Mark R; Borjigin, Jimo; Wang, Michael M

    2011-12-01

    Sleep disorders are important risk factors for stroke; conversely, stroke patients suffer from sleep disturbances including disruptions of non-rapid eye movement (NREM) and rapid eye movement (REM) sleep and a decrease in total sleep. This study was performed to characterize the effect of stroke on sleep architecture of rats using continuous electroencephalography (EEG) and activity monitoring. Rats were implanted with transmitters which enabled continuous real time recording of EEG, electromyography (EMG), and locomotor activity. Baseline recordings were performed prior to induction of either transient middle cerebral artery (MCA) occlusion or sham surgery. Sleep recordings were obtained for 60 h after surgery to identify periods of wakefulness, NREM, and REM sleep before and after stroke. Spectral analysis was performed to assess the effects of stroke on state-dependent EEG. Finally, we quantified the time in wake, NREM, and REM sleep before and after stroke. Delta power, a measure of NREM sleep depth, was increased the day following stroke. At the same time, there was a significant shift in theta rhythms to a lower frequency during REM and wake periods. The awake EEG slowed after stroke over both hemispheres. The EEG of the ischemic hemisphere demonstrated diminished theta power specific to REM in excess of the slowing seen over the contralateral hemisphere. In contrast to rats exposed to sham surgery which had slightly increased total sleep, rats undergoing stroke experienced decreased total sleep. The decrease in total sleep after stroke was the result of dramatic reduction in the amount of REM sleep after ischemia. The suppression of REM after stroke was due to a decrease in the number of REM bouts; the length of the average REM bout did not change. We conclude that after stroke in this experimental model, REM sleep of rats is specifically and profoundly suppressed. Further experiments using this experimental model should be performed to investigate the

  11. INVESTIGATION OF THE EXTENDED RANGE REM-COUNTER SMARTREM-LINUS IN REFERENCE AND WORKPLACE FIELDS EXPECTED AROUND HIGH-ENERGY ACCELERATORS.

    PubMed

    Hohmann, Eike; Trovati, S; Strauch, U; Mayer, S

    2016-09-01

    Radiation survey instrumentation is adequate for the use around high-energy accelerators if capable to measure the dose arising from neutrons with energies ranging from thermal up to a few gigaelectronvolts. The SmartREM-LINUS is a commercial extended range rem-counter, consisting of a central (3)He-proportional counter surrounded by a spherical moderator made of borated polyethylene with an internal shield made of lead. The dose rate indicated by the SmartREM-LINUS was investigated for two different irradiation conditions. The linearity and the angular dependence of the indicated dose rate were investigated using reference neutron fields produced by (241)AmBe and (252)Cf. Additional measurements were performed in two different workplace fields with a component of neutrons with energies >20 MeV, namely the CERN-EU high-energy reference field and near the beam dump of the SwissFEL injector test facility. The measured dose rates were compared to a commercial rem-counter (WENDI2) and the results of Monte Carlo simulations.

  12. Neutron measurements

    SciTech Connect

    McCall, R.C.

    1981-01-01

    Methods of neutron detection and measurement are discussed. Topics include sources of neutrons, neutrons in medicine, interactions of neutrons with matter, neutron shielding, neutron measurement units, measurement methods, and neutron spectroscopy. (ACR)

  13. Endogenous cholinergic input to the pontine REM sleep generator is not required for REM sleep to occur.

    PubMed

    Grace, Kevin P; Vanstone, Lindsay E; Horner, Richard L

    2014-10-22

    Initial theories of rapid eye movement (REM) sleep generation posited that induction of the state required activation of the pontine subceruleus (SubC) by cholinergic inputs. Although the capacity of cholinergic neurotransmission to contribute to REM sleep generation has been established, the role of cholinergic inputs in the generation of REM sleep is ultimately undetermined as the critical test of this hypothesis (local blockade of SubC acetylcholine receptors) has not been rigorously performed. We used bilateral microdialysis in freely behaving rats (n = 32), instrumented for electroencephalographic and electromyographic recording, to locally manipulate neurotransmission in the SubC with select drugs. As predicted, combined microperfusion of D-AP5 (glutamate receptor antagonist) and muscimol (GABAA receptor agonist) in the SubC virtually eliminated REM sleep. However, REM sleep was not reduced by scopolamine microperfusion in this same region, at a concentration capable of blocking the effects of cholinergic receptor stimulation. This result suggests that transmission of REM sleep drive to the SubC is acetylcholine-independent. Although SubC cholinergic inputs are not majorly involved in REM sleep generation, they may perform a minor function in the reinforcement of transitions into REM sleep, as evidenced by increases in non-REM-to-REM sleep transition duration and failure rate during cholinergic receptor blockade. Cholinergic receptor antagonism also attenuated the normal increase in hippocampal θ oscillations that characterize REM sleep. Using computational modeling, we show that our in vivo results are consistent with a mutually excitatory interaction between the SubC and cholinergic neurons where, importantly, cholinergic neuron activation is gated by SubC activity.

  14. REM Sleep at its Core – Circuits, Neurotransmitters, and Pathophysiology

    PubMed Central

    Fraigne, Jimmy J.; Torontali, Zoltan A.; Snow, Matthew B.; Peever, John H.

    2015-01-01

    Rapid eye movement (REM) sleep is generated and maintained by the interaction of a variety of neurotransmitter systems in the brainstem, forebrain, and hypothalamus. Within these circuits lies a core region that is active during REM sleep, known as the subcoeruleus nucleus (SubC) or sublaterodorsal nucleus. It is hypothesized that glutamatergic SubC neurons regulate REM sleep and its defining features such as muscle paralysis and cortical activation. REM sleep paralysis is initiated when glutamatergic SubC cells activate neurons in the ventral medial medulla, which causes release of GABA and glycine onto skeletal motoneurons. REM sleep timing is controlled by activity of GABAergic neurons in the ventrolateral periaqueductal gray and dorsal paragigantocellular reticular nucleus as well as melanin-concentrating hormone neurons in the hypothalamus and cholinergic cells in the laterodorsal and pedunculo-pontine tegmentum in the brainstem. Determining how these circuits interact with the SubC is important because breakdown in their communication is hypothesized to underlie narcolepsy/cataplexy and REM sleep behavior disorder (RBD). This review synthesizes our current understanding of mechanisms generating healthy REM sleep and how dysfunction of these circuits contributes to common REM sleep disorders such as cataplexy/narcolepsy and RBD. PMID:26074874

  15. Neutron and Proton Dosages in the Upper Atmosphere from Solar Flare Radiation.

    PubMed

    Flamm, E J; Lingenfelter, R E

    1964-06-26

    The radiation dosage from secondary neutrons as well as from primary and secondary protons in the earth's atmosphere during solar particle events is calculated as a function of the solar proton flux, atmospheric depth, and geomagnetic-cutoff rigidity. The dosage in rems from secondary neutrons exceeds the dosage from protons below 30 g/cm(2) of residual atmosphere. Neutron dosages in rads are less than the dosage from primary protons at all depths above 100 g/cm(2). The maximum neutron dose to travelers in supersonic aircraft during solar particle events of the magnitude observed during the last solar cycle would be of the order of I rem.

  16. [Trazodone in REM sleep behavior disorder].

    PubMed

    Chica-Urzola, Heydy Luz

    2015-01-01

    This case concerns an elderly man with a REM sleep behavior disorder, who was initially offered a pharmacological treatment with clonazepam, recommended by other articles, but with poor adherence due to its adverse reactions and persistence of symptoms. He was then offered a treatment with Trazodone was offered, achieving a complete remission of symptoms, with no reported side effects. It is clear that Trazodone has no known indication for this type of disorder; nevertheless, it was considered in this case because of its pharmacological profile, obtaining satisfactory results. Further research is needed in order to document thoroughly the mechanisms of action, efficacy and utility of this molecule in cases such as the one presented.

  17. The role of REM sleep theta activity in emotional memory

    PubMed Central

    Hutchison, Isabel C.; Rathore, Shailendra

    2015-01-01

    While non-REM (NREM) sleep has been strongly implicated in the reactivation and consolidation of memory traces, the role of rapid-eye movement (REM) sleep remains unclear. A growing body of research on humans and animals provide behavioral evidence for a role of REM sleep in the strengthening and modulation of emotional memories. Theta activity—which describes low frequency oscillations in the local field potential within the hippocampus, amygdala and neocortex—is a prominent feature of both wake and REM sleep in humans and rodents. Theta coherence between the hippocampus and amygdala drives large-scale pontine-geniculo-occipital (PGO) waves, the density of which predicts increases in plasticity-related gene expression. This could potentially facilitate the processing of emotional memory traces within the hippocampus during REM sleep. Further, the timing of hippocampal activity in relation to theta phase is vital in determining subsequent potentiation of neuronal activity. This could allow the emotionally modulated strengthening of novel and gradual weakening of consolidated hippocampal memory traces during REM sleep. Hippocampal theta activity is also correlated with REM sleep levels of achetylcholine - which is thought to reduce hippocampal inputs in the neocortex. The additional low levels of noradrenaline during REM sleep, which facilitate feedback within the neocortex, could allow the integration of novel memory traces previously consolidated during NREM sleep. We therefore propose that REM sleep mediates the prioritized processing of emotional memories within the hippocampus, the integration of previously consolidated memory traces within the neocortex, as well as the disengagement of consolidated neocortical memory traces from the hippocampus. PMID:26483709

  18. The role of REM sleep theta activity in emotional memory.

    PubMed

    Hutchison, Isabel C; Rathore, Shailendra

    2015-01-01

    While non-REM (NREM) sleep has been strongly implicated in the reactivation and consolidation of memory traces, the role of rapid-eye movement (REM) sleep remains unclear. A growing body of research on humans and animals provide behavioral evidence for a role of REM sleep in the strengthening and modulation of emotional memories. Theta activity-which describes low frequency oscillations in the local field potential within the hippocampus, amygdala and neocortex-is a prominent feature of both wake and REM sleep in humans and rodents. Theta coherence between the hippocampus and amygdala drives large-scale pontine-geniculo-occipital (PGO) waves, the density of which predicts increases in plasticity-related gene expression. This could potentially facilitate the processing of emotional memory traces within the hippocampus during REM sleep. Further, the timing of hippocampal activity in relation to theta phase is vital in determining subsequent potentiation of neuronal activity. This could allow the emotionally modulated strengthening of novel and gradual weakening of consolidated hippocampal memory traces during REM sleep. Hippocampal theta activity is also correlated with REM sleep levels of achetylcholine - which is thought to reduce hippocampal inputs in the neocortex. The additional low levels of noradrenaline during REM sleep, which facilitate feedback within the neocortex, could allow the integration of novel memory traces previously consolidated during NREM sleep. We therefore propose that REM sleep mediates the prioritized processing of emotional memories within the hippocampus, the integration of previously consolidated memory traces within the neocortex, as well as the disengagement of consolidated neocortical memory traces from the hippocampus.

  19. Analysis of the arabidopsis REM gene family predicts functions during flower development

    PubMed Central

    Mantegazza, Otho; Gregis, Veronica; Mendes, Marta Adelina; Morandini, Piero; Alves-Ferreira, Márcio; Patreze, Camila M.; Nardeli, Sarah M.; Kater, Martin M.; Colombo, Lucia

    2014-01-01

    Background and Aims The REM (Reproductive Meristem) gene family of Arabidopsis thaliana is part of the B3 DNA-binding domain superfamily. Despite the fact that several groups have worked on the REM genes for many years, little is known about the function of this transcription factor family. This study aims to identify a set of REM genes involved in flower development and to characterize their function. Methods In order to provide an overview of the REM gene family, a detailed expression analysis for all REM genes of A. thaliana was performed and combined with a meta-analysis of ChIP-sequencing and microarray experiments. Key Results Two sets of phylogenetically closely related REM genes, namely REM23, REM24 and REM25, and REM34, REM35 and REM36, were identified as possibly being involved in the early stages of flower development. Single- and double-mutant combinations were analysed for these genes, and no phenotypic effects were detected during flower development. Conclusions The data suggest that the REM34, REM35 and REM36 group is the most interesting one, as REM34 is co-expressed with the floral meristem identity (FMI) genes, they are bound by AP1, SVP, AP3 and PI, and they are expressed in the floral meristem and during the earliest stages of flower development. However, it appears that high levels of functional redundancy may conceal the exact function of these transcription factor genes. PMID:25002525

  20. Neuroscience: A Distributed Neural Network Controls REM Sleep.

    PubMed

    Peever, John; Fuller, Patrick M

    2016-01-11

    How does the brain control dreams? New science shows that a small node of cells in the medulla - the most primitive part of the brain - may function to control REM sleep, the brain state that underlies dreaming.

  1. Materials properties, loads, and stress analysis, Spartan REM: Appendix A

    NASA Technical Reports Server (NTRS)

    Marlowe, D. S.; West, E. J.

    1984-01-01

    The mechanical properties, load tests, and stress analysis of the Spartan Release Engagement Mechanism (REM) is presented. The fracture properties of the components of the unit are also discussed. Detailed engineering drawings are included.

  2. Computer models and output, Spartan REM: Appendix B

    NASA Technical Reports Server (NTRS)

    Marlowe, D. S.; West, E. J.

    1984-01-01

    A computer model of the Spartan Release Engagement Mechanism (REM) is presented in a series of numerical charts and engineering drawings. A crack growth analysis code is used to predict the fracture mechanics of critical components.

  3. Slow waves, sharp waves, ripples, and REM in sleeping dragons.

    PubMed

    Shein-Idelson, Mark; Ondracek, Janie M; Liaw, Hua-Peng; Reiter, Sam; Laurent, Gilles

    2016-04-29

    Sleep has been described in animals ranging from worms to humans. Yet the electrophysiological characteristics of brain sleep, such as slow-wave (SW) and rapid eye movement (REM) activities, are thought to be restricted to mammals and birds. Recording from the brain of a lizard, the Australian dragon Pogona vitticeps, we identified SW and REM sleep patterns, thus pushing back the probable evolution of these dynamics at least to the emergence of amniotes. The SW and REM sleep patterns that we observed in lizards oscillated continuously for 6 to 10 hours with a period of ~80 seconds. The networks controlling SW-REM antagonism in amniotes may thus originate from a common, ancient oscillator circuit. Lizard SW dynamics closely resemble those observed in rodent hippocampal CA1, yet they originate from a brain area, the dorsal ventricular ridge, that has no obvious hodological similarity with the mammalian hippocampus.

  4. DC attenuation meter

    DOEpatents

    Hargrove, Douglas L.

    2004-09-14

    A portable, hand-held meter used to measure direct current (DC) attenuation in low impedance electrical signal cables and signal attenuators. A DC voltage is applied to the signal input of the cable and feedback to the control circuit through the signal cable and attenuators. The control circuit adjusts the applied voltage to the cable until the feedback voltage equals the reference voltage. The "units" of applied voltage required at the cable input is the system attenuation value of the cable and attenuators, which makes this meter unique. The meter may be used to calibrate data signal cables, attenuators, and cable-attenuator assemblies.

  5. Groundwater-Seepage Meter

    NASA Technical Reports Server (NTRS)

    Walthall, Harry G.; Reay, William G.

    1993-01-01

    Instrument measures seepage of groundwater into inland or coastal body of water. Positioned at depth as great as 40 meters, and measures flow at low rate and low pressure differential. Auxiliary pressure meter provides data for correlation of flow of groundwater with tides and sea states. Seepage meter operates independently for several weeks. Its sampling rate adjusted to suit hydrologic conditions; to measure more frequently when conditions changing rapidly. Used in water-quality management and for biological and geological research. Potential industrial uses include measurement of seepage of caustic and corrosive liquids.

  6. The Swift Mission and the REM Telescope

    NASA Technical Reports Server (NTRS)

    Gehrels, N.; Chincarini, G.; Giommi, P.; Mason, K. O.; Nousek, J. A.; Wells, A. A.; White, N. E.; Barthelemy, S. D.; Burrow, D. N.; Hurley, K. C.

    2003-01-01

    Following a description of the science drive which originated the Swift Mission, this is US NASA MIDEX Mission with the collaboration of Italy and the UK, we will describe the status of the hardware and the observing strategy. The telemetry is carried out via the TDRSS satellite for those communications that need immediate response. The data transfer and the scheduled uploading of routine commands will be done through the ASI Malindi station in Kenia. Both in the US and in Europe a large effort will be done to follow the bursts with the maximum of efficiency and as soon as possible after the alert. We will describe how the ESO VLT telescopes are able to respond to the alert. To address the problematic of the dark bursts and to immediately follow up all of the bursts also in the Near Infrared we designed and built a 60 cm NIR Robotic telescope, REM, to be located on the ESO ground at Cerro La Silla. The instrumentation includes also a low dispersion spectrograph with the capability of multi wavelength optical photometry.

  7. Your Glucose Meter

    MedlinePlus

    ... Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco ... 164KB) En Español Basic Facts 7 Tips for Testing Your Blood Sugar and Caring for Your Meter ...

  8. Space Age Meter.

    ERIC Educational Resources Information Center

    Phillips, Julie

    1983-01-01

    Discusses the history and evolution of measurement standards from 3000 BC to the modern metric system. Traces measurement techniques from comparisons with the human body to use of atomic clocks and lasers to establish the length of a meter. (JM)

  9. Peak flow meter (image)

    MedlinePlus

    A peak flow meter is commonly used by a person with asthma to measure the amount of air that can be ... become narrow or blocked due to asthma, peak flow values will drop because the person cannot blow ...

  10. DIGITAL Q METER

    DOEpatents

    Briscoe, W.L.

    1962-02-13

    A digital Q meter is described for measuring the Q of mechanical or electrical devices. The meter comprises in combination a transducer coupled to an input amplifier, and an upper and lower level discriminator coupled to the amplifier and having their outputs coupled to an anticoincidence gate. The output of the gate is connected to a scaler. The lower level discriminator is adjusted to a threshold level of 36.8 percent of the operating threshold level of the upper level discriminator. (AEC)

  11. Arrival Metering Precision Study

    NASA Technical Reports Server (NTRS)

    Prevot, Thomas; Mercer, Joey; Homola, Jeffrey; Hunt, Sarah; Gomez, Ashley; Bienert, Nancy; Omar, Faisal; Kraut, Joshua; Brasil, Connie; Wu, Minghong, G.

    2015-01-01

    This paper describes the background, method and results of the Arrival Metering Precision Study (AMPS) conducted in the Airspace Operations Laboratory at NASA Ames Research Center in May 2014. The simulation study measured delivery accuracy, flight efficiency, controller workload, and acceptability of time-based metering operations to a meter fix at the terminal area boundary for different resolution levels of metering delay times displayed to the air traffic controllers and different levels of airspeed information made available to the Time-Based Flow Management (TBFM) system computing the delay. The results show that the resolution of the delay countdown timer (DCT) on the controllers display has a significant impact on the delivery accuracy at the meter fix. Using the 10 seconds rounded and 1 minute rounded DCT resolutions resulted in more accurate delivery than 1 minute truncated and were preferred by the controllers. Using the speeds the controllers entered into the fourth line of the data tag to update the delay computation in TBFM in high and low altitude sectors increased air traffic control efficiency and reduced fuel burn for arriving aircraft during time based metering.

  12. Functional Anatomy of Non-REM Sleep.

    PubMed

    de Andrés, Isabel; Garzón, Miguel; Reinoso-Suárez, Fernando

    2011-01-01

    The state of non-REM sleep (NREM), or slow wave sleep, is associated with a synchronized EEG pattern in which sleep spindles and/or K complexes and high-voltage slow wave activity (SWA) can be recorded over the entire cortical surface. In humans, NREM is subdivided into stages 2 and 3-4 (presently named N3) depending on the proportions of each of these polygraphic events. NREM is necessary for normal physical and intellectual performance and behavior. An overview of the brain structures involved in NREM generation shows that the thalamus and the cerebral cortex are absolutely necessary for the most significant bioelectric and behavioral events of NREM to be expressed; other structures like the basal forebrain, anterior hypothalamus, cerebellum, caudal brain stem, spinal cord and peripheral nerves contribute to NREM regulation and modulation. In NREM stage 2, sustained hyperpolarized membrane potential levels resulting from interaction between thalamic reticular and projection neurons gives rise to spindle oscillations in the membrane potential; the initiation and termination of individual spindle sequences depends on corticothalamic activities. Cortical and thalamic mechanisms are also involved in the generation of EEG delta SWA that appears in deep stage 3-4 (N3) NREM; the cortex has classically been considered to be the structure that generates this activity, but delta oscillations can also be generated in thalamocortical neurons. NREM is probably necessary to normalize synapses to a sustainable basal condition that can ensure cellular homeostasis. Sleep homeostasis depends not only on the duration of prior wakefulness but also on its intensity, and sleep need increases when wakefulness is associated with learning. NREM seems to ensure cell homeostasis by reducing the number of synaptic connections to a basic level; based on simple energy demands, cerebral energy economizing during NREM sleep is one of the prevalent hypotheses to explain NREM homeostasis.

  13. Functional Anatomy of Non-REM Sleep

    PubMed Central

    de Andrés, Isabel; Garzón, Miguel; Reinoso-Suárez, Fernando

    2011-01-01

    The state of non-REM sleep (NREM), or slow wave sleep, is associated with a synchronized EEG pattern in which sleep spindles and/or K complexes and high-voltage slow wave activity (SWA) can be recorded over the entire cortical surface. In humans, NREM is subdivided into stages 2 and 3–4 (presently named N3) depending on the proportions of each of these polygraphic events. NREM is necessary for normal physical and intellectual performance and behavior. An overview of the brain structures involved in NREM generation shows that the thalamus and the cerebral cortex are absolutely necessary for the most significant bioelectric and behavioral events of NREM to be expressed; other structures like the basal forebrain, anterior hypothalamus, cerebellum, caudal brain stem, spinal cord and peripheral nerves contribute to NREM regulation and modulation. In NREM stage 2, sustained hyperpolarized membrane potential levels resulting from interaction between thalamic reticular and projection neurons gives rise to spindle oscillations in the membrane potential; the initiation and termination of individual spindle sequences depends on corticothalamic activities. Cortical and thalamic mechanisms are also involved in the generation of EEG delta SWA that appears in deep stage 3–4 (N3) NREM; the cortex has classically been considered to be the structure that generates this activity, but delta oscillations can also be generated in thalamocortical neurons. NREM is probably necessary to normalize synapses to a sustainable basal condition that can ensure cellular homeostasis. Sleep homeostasis depends not only on the duration of prior wakefulness but also on its intensity, and sleep need increases when wakefulness is associated with learning. NREM seems to ensure cell homeostasis by reducing the number of synaptic connections to a basic level; based on simple energy demands, cerebral energy economizing during NREM sleep is one of the prevalent hypotheses to explain NREM homeostasis

  14. Optogenetic activation of cholinergic neurons in the PPT or LDT induces REM sleep.

    PubMed

    Van Dort, Christa J; Zachs, Daniel P; Kenny, Jonathan D; Zheng, Shu; Goldblum, Rebecca R; Gelwan, Noah A; Ramos, Daniel M; Nolan, Michael A; Wang, Karen; Weng, Feng-Ju; Lin, Yingxi; Wilson, Matthew A; Brown, Emery N

    2015-01-13

    Rapid eye movement (REM) sleep is an important component of the natural sleep/wake cycle, yet the mechanisms that regulate REM sleep remain incompletely understood. Cholinergic neurons in the mesopontine tegmentum have been implicated in REM sleep regulation, but lesions of this area have had varying effects on REM sleep. Therefore, this study aimed to clarify the role of cholinergic neurons in the pedunculopontine tegmentum (PPT) and laterodorsal tegmentum (LDT) in REM sleep generation. Selective optogenetic activation of cholinergic neurons in the PPT or LDT during non-REM (NREM) sleep increased the number of REM sleep episodes and did not change REM sleep episode duration. Activation of cholinergic neurons in the PPT or LDT during NREM sleep was sufficient to induce REM sleep.

  15. Water cycle at Gale crater through MSL/REMS observations

    NASA Astrophysics Data System (ADS)

    Harri, Ari-Matti; Genzer, Maria; Kemppinen, Osku; Gomez-Elvira, Javier; Savijärvi, Hannu; McConnochie, Tim; De la Torre, Manuel; Haberle, Robert; Polkko, Jouni; Paton, Mark; Richardson, Mark I.; Newman, Claire E.; Siili, Tero; Makinen, Terhi

    2016-10-01

    The Mars Science laboratory (MSL) has been successfully operating at the Gale crater since early August 2012 and has provided a wealth of extremely valuable data. That includes atmospheric observations by the REMS instrument performing atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity (REMS-H), and UV measurements.The REMS-H relative humidity device is based on polymeric capacitive humidity sensors developed by Vaisala Inc. and it makes use of three (3) humidity sensor heads. The humidity device is mounted on the REMS boom providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust.The REMS-H humidity instrument has created an unprecedented data record of more than two full Martian. REMS-H measured the relative humidity and temperature at 1.6 m height for a period of 5 minutes every hour as part of the MSL/REMS instrument package. We focus on describing the annual in situ water cycle with the new REMS-H instrument calibration for the period of two Martian years. The results will be constrained through comparison with independent indirect observations and through modeling efforts.We inferred the hourly atmospheric VMR from the REMS-H observations and compared these VMR measurements with predictions of VMR from our 1D column Martian atmospheric model and regolith to investigate the local water cycle, exchange processes and the local climate in Gale Crater. The strong diurnal variation suggests there are surface-atmosphere exchange processes at Gale Crater during all seasons, which depletes moisture to the ground in the evening and nighttime and release the moisture back to the atmosphere during the daytime. On the other hand, these processes do not result in significant water deposition on the ground, because frost has not been detected in Gale Crater by any of the MSL observations. Hence, our modelling results presumably indicate that adsorption processes take

  16. Preliminary Interpretation of the MSL REMS Pressure Data

    NASA Astrophysics Data System (ADS)

    Haberle, Robert; Gómez-Elvira, Javier; de la Torre Juárez, Manuel; Harri, Ari-Matti; Hollingsworth, Jeffery; Kahanpää, Henrik; Kahre, Melinda; Martin-Torres, Javier; Mischna, Michael; Newman, Claire; Rafkin, Scot; Rennó, Nilton; Richardson, Mark; Rodríguez-Manfredi, Jose; Vasavada, Ashwin; Zorzano, Maria-Paz; REMS/MSL Science Teams

    2013-04-01

    The Rover Environmental Monitoring Station (REMS) on the Mars Science Laboratory (MSL) Curiosity rover consists of a suite of meteorological instruments that measure pressure, temperature (air and ground), wind (speed and direction), relative humidity, and the UV flux. A detailed description of the REMS sensors and their performance can be found in Gómez-Elvira et al. [2012, Space Science Reviews, 170(1-4), 583-640]. Here we focus on interpreting the first 100 sols of REMS operations with a particular emphasis on the pressure data. A unique feature of pressure data is that they reveal information on meteorological phenomena with time scales from seconds to years and spatial scales from local to global. From a single station we can learn about dust devils, regional circulations, thermal tides, synoptic weather systems, the CO2 cycle, dust storms, and interannual variability. Thus far MSL's REMS pressure sensor, provided by the Finnish Meteorological Institute and integrated into the REMS payload by Centro de Astrobiología, is performing flawlessly and our preliminary interpretation of its data includes the discovery of relatively dust-free convective vortices; a regional circulation system significantly modified by Gale crater and its central mound; the strongest thermal tides yet measured from the surface of Mars whose amplitudes and phases are very sensitive to fluctuations in global dust loading; and the classical signature of the seasonal cycling of carbon dioxide into and out of the polar caps.

  17. Optical watthour meter digitizer

    SciTech Connect

    Andrews, W.H.

    1980-10-01

    As concern about energy conservation and energy-use efficiency increases, a simple and inexpensive instrument that would provide accurate, reliable and high-resolution data on electrical energy usage should find widespread application in research and industrial facilities. An instrument that would also provide one or more outputs compatible with a wide range of digital data acquisition systems would be especially appropriate, since the use of automatic data logging equipment is now common, even in small-scale and low-budget operations. An optical watthour meter digitizer was developed which meets these criteria. Based on the induction-type watthour meter, the digitizer provides an output pulse for a fixed amount of energy use. The digitizer senses the motion of the rotor disc of the meter by optically detecting passage of a nonreflective area painted on the underside of the disc. The passage of such area initiates a logic-compatible output pulse that can be used to measure power or energy usage in a variety of ways. The accuracy of the measurement is determined by the watthour meter. The resolution of the measurement is determined by the K/sub h/ constant (in watthours per revolution) of the meter and the number of equally spaced targets painted on the disc. The resolution of this device can be as small as a fraction of a watthour; the resolution of the manually read register on a watthour meter is typically a fraction of a kilowatthour. Several digitizers were fabricated, bench-tested, and installed in the field for long-term performance testing. All are performing satisfactorily.

  18. Neutron multiplicity ,easurements With 3He alternative: Straw neutron detectors

    DOE PAGES

    Mukhopadhyay, Sanjoy; Wolff, Ronald S.; Meade, John A.; ...

    2015-01-27

    Counting neutrons emitted by special nuclear material (SNM) and differentiating them from the background neutrons of various origins is the most effective passive means of detecting SNM. Unfortunately, neutron detection, counting, and partitioning in a maritime environment are complex due to the presence of high-multiplicity spallation neutrons (commonly known as “ship effect”) and to the complicated nature of the neutron scattering in that environment. In this study, a prototype neutron detector was built using 10B as the converter in a special form factor called “straws” that would address the above problems by looking into the details of multiplicity distributions ofmore » neutrons originating from a fissioning source. This paper describes the straw neutron multiplicity counter (NMC) and assesses the performance with those of a commercially available fission meter. The prototype straw neutron detector provides a large-area, efficient, lightweight, more granular (than fission meter) neutron-responsive detection surface (to facilitate imaging) to enhance the ease of application of fission meters. Presented here are the results of preliminary investigations, modeling, and engineering considerations leading to the construction of this prototype. This design is capable of multiplicity and Feynman variance measurements. This prototype may lead to a near-term solution to the crisis that has arisen from the global scarcity of 3He by offering a viable alternative to fission meters. This paper describes the work performed during a 2-year site-directed research and development (SDRD) project that incorporated straw detectors for neutron multiplicity counting. The NMC is a two-panel detector system. We used 10B (in the form of enriched boron carbide: 10B4C) for neutron detection instead of 3He. In the first year, the project worked with a panel of straw neutron detectors, investigated its characteristics, and developed a data acquisition (DAQ) system to collect

  19. A Temporally Controlled Inhibitory Drive Coordinates Twitch Movements during REM Sleep.

    PubMed

    Brooks, Patricia L; Peever, John

    2016-05-09

    During REM sleep, skeletal muscles are paralyzed in one moment but twitch and jerk in the next. REM sleep twitches are traditionally considered random motor events that result from momentary lapses in REM sleep paralysis [1-3]. However, recent evidence indicates that twitches are not byproducts of REM sleep, but are in fact self-generated events that could function to promote motor learning and development [4-6]. If REM twitches are indeed purposefully generated, then they should be controlled by a coordinated and definable mechanism. Here, we used behavioral, electrophysiological, pharmacological, and neuroanatomical methods to demonstrate that an inhibitory drive onto skeletal motoneurons produces a temporally coordinated pattern of muscle twitches during REM sleep. First, we show that muscle twitches in adult rats are not uniformly distributed during REM sleep, but instead follow a well-defined temporal trajectory. They are largely absent during REM initiation but increase steadily thereafter, peaking toward REM termination. Next, we identify the transmitter mechanism that controls the temporal nature of twitch activity. Specifically, we show that a GABA and glycine drive onto motoneurons prevents twitch activity during REM initiation, but progressive weakening of this drive functions to promote twitch activity during REM termination. These results demonstrate that REM twitches are not random byproducts of REM sleep, but are instead rather coherently generated events controlled by a temporally variable inhibitory drive.

  20. Cold exposure impairs dark-pulse capacity to induce REM sleep in the albino rat.

    PubMed

    Baracchi, Francesca; Zamboni, Giovanni; Cerri, Matteo; Del Sindaco, Elide; Dentico, Daniela; Jones, Christine Ann; Luppi, Marco; Perez, Emanuele; Amici, Roberto

    2008-06-01

    In the albino rat, a REM sleep (REMS) onset can be induced with a high probability and a short latency when the light is suddenly turned off (dark pulse, DP) during non-REM sleep (NREMS). The aim of this study was to investigate to what extent DP delivery could overcome the integrative thermoregulatory mechanisms that depress REMS occurrence during exposure to low ambient temperature (Ta). To this aim, the efficiency of a non-rhythmical repetitive DP (3 min each) delivery during the first 6-h light period of a 12 h:12 h light-dark cycle in inducing REMS was studied in the rat, through the analysis of electroencephalogram, electrocardiogram, hypothalamic temperature and motor activity at different Tas. The results showed that DP delivery triggers a transition from NREMS to REMS comparable to that which occurs spontaneously. However, the efficiency of DP delivery in inducing REMS was reduced during cold exposure to an extent comparable with that observed in spontaneous REMS occurrence. Such impairment was associated with low Delta activity and high sympathetic tone when DPs were delivered. Repetitive DP administration increased REMS amount during the delivery period and a subsequent negative REMS rebound was observed. In conclusion, DP delivery did not overcome the integrative thermoregulatory mechanisms that depress REMS in the cold. These results underline the crucial physiological meaning of the mutual exclusion of thermoregulatory activation and REMS occurrence, and support the hypothesis that the suspension of the central control of body temperature is a prerequisite for REMS occurrence.

  1. Coupled Flip-Flop Model for REM Sleep Regulation in the Rat

    PubMed Central

    Dunmyre, Justin R.; Mashour, George A.; Booth, Victoria

    2014-01-01

    Recent experimental studies investigating the neuronal regulation of rapid eye movement (REM) sleep have identified mutually inhibitory synaptic projections among REM sleep-promoting (REM-on) and REM sleep-inhibiting (REM-off) neuronal populations that act to maintain the REM sleep state and control its onset and offset. The control mechanism of mutually inhibitory synaptic interactions mirrors the proposed flip-flop switch for sleep-wake regulation consisting of mutually inhibitory synaptic projections between wake- and sleep-promoting neuronal populations. While a number of synaptic projections have been identified between these REM-on/REM-off populations and wake/sleep-promoting populations, the specific interactions that govern behavioral state transitions have not been completely determined. Using a minimal mathematical model, we investigated behavioral state transition dynamics dictated by a system of coupled flip-flops, one to control transitions between wake and sleep states, and another to control transitions into and out of REM sleep. The model describes the neurotransmitter-mediated inhibitory interactions between a wake- and sleep-promoting population, and between a REM-on and REM-off population. We proposed interactions between the wake/sleep and REM-on/REM-off flip-flops to replicate the behavioral state statistics and probabilities of behavioral state transitions measured from experimental recordings of rat sleep under ad libitum conditions and after 24 h of REM sleep deprivation. Reliable transitions from REM sleep to wake, as dictated by the data, indicated the necessity of an excitatory projection from the REM-on population to the wake-promoting population. To replicate the increase in REM-wake-REM transitions observed after 24 h REM sleep deprivation required that this excitatory projection promote transient activation of the wake-promoting population. Obtaining the reliable wake-nonREM sleep transitions observed in the data required that

  2. REM-dreams recall in patients with narcolepsy-cataplexy.

    PubMed

    Mazzetti, Michela; Bellucci, Claudia; Mattarozzi, Katia; Plazzi, Giuseppe; Tuozzi, Giovanni; Cipolli, Carlo

    2010-01-15

    An abundant recall of dreams has been observed in clinical studies on patients with narcolepsy-cataplexy (NC), a neurological disorder characterized by an altered sleep architecture. Laboratory studies have shown that dream experiences developed during 1st-rapid eye movement (REM) sleep by NC patients are longer and more complex than those of healthy subjects. To establish whether these features indicate an earlier optimal functioning of the cognitive processes involved in dream generation rather than a more accurate dream recall, we compared the indicators of length and structural organization in reports of REM-dreams collected from 14 NC patients and their matched controls. During an experimental night two awakenings were provoked after 8 min in 1st- and 3rd-REM sleep; participants were asked to report their dream experience (spontaneous report) and then, if possible, further remembered parts of this experience (prompted report). All reports were analyzed using story-grammar rules, which allow us to identify units larger than single contents and describe their story-like organization. While dream recall (about 90%) was comparable in NC patients and controls, 1st-REM spontaneous reports were longer and more complex in NC patients, half of whom also provided prompted reports. After 3rd-REM awakening more than one third of NC patients and controls gave prompted reports, which were fairly comparable in length and complexity with the spontaneous reports. These findings confirm that the cognitive processes underlying dream generation reach their optimal functioning earlier in the night in NC patients than in normal subjects, and raises the question of whether the dream-stories described in spontaneous and prompted reports are part of the same or distinct REM-dreams.

  3. Transformer and Meter Tester

    NASA Technical Reports Server (NTRS)

    Stoms, R. M.

    1984-01-01

    Numerically-controlled 5-axis machine tool uses transformer and meter to determine and indicate whether tool is in home position, but lacks built-in test mode to check them. Tester makes possible test, and repair of components at machine rather then replace them when operation seems suspect.

  4. Metering Characteristics of Carburetors

    NASA Technical Reports Server (NTRS)

    Tice, Percival S; Dickinson, H C

    1919-01-01

    Report presents the results of an extensive experimental investigation of the performance of different types of carburetors as effecting the maintenance under all conditions of correct ratio between the weights of fuel and air. It also gives a description of the Bureau of Standards carburetor test plant, test equipment and measuring instruments used to determine the metering characteristics of carburetors.

  5. Elbow mass flow meter

    DOEpatents

    McFarland, Andrew R.; Rodgers, John C.; Ortiz, Carlos A.; Nelson, David C.

    1994-01-01

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  6. The Neurobiological Mechanisms and Treatments of REM Sleep Disturbances in Depression.

    PubMed

    Wang, Yi-Qun; Li, Rui; Zhang, Meng-Qi; Zhang, Ze; Qu, Wei-Min; Huang, Zhi-Li

    2015-01-01

    Most depressed patients suffer from sleep abnormalities, which are one of the critical symptoms of depression. They are robust risk factors for the initiation and development of depression. Studies about sleep electroencephalograms have shown characteristic changes in depression such as reductions in non-rapid eye movement sleep production, disruptions of sleep continuity and disinhibition of rapid eye movement (REM) sleep. REM sleep alterations include a decrease in REM sleep latency, an increase in REM sleep duration and REM sleep density with respect to depressive episodes. Emotional brain processing dependent on the normal sleep-wake regulation seems to be failed in depression, which also promotes the development of clinical depression. Also, REM sleep alterations have been considered as biomarkers of depression. The disturbances of norepinephrine and serotonin systems may contribute to REM sleep abnormalities in depression. Lastly, this review also discusses the effects of different antidepressants on REM sleep disturbances in depression.

  7. The Neurobiological Mechanisms and Treatments of REM Sleep Disturbances in Depression

    PubMed Central

    Wang, Yi-Qun; Li, Rui; Zhang, Meng-Qi; Zhang, Ze; Qu, Wei-Min; Huang, Zhi-Li

    2015-01-01

    Most depressed patients suffer from sleep abnormalities, which are one of the critical symptoms of depression. They are robust risk factors for the initiation and development of depression. Studies about sleep electroencephalograms have shown characteristic changes in depression such as reductions in non-rapid eye movement sleep production, disruptions of sleep continuity and disinhibition of rapid eye movement (REM) sleep. REM sleep alterations include a decrease in REM sleep latency, an increase in REM sleep duration and REM sleep density with respect to depressive episodes. Emotional brain processing dependent on the normal sleep-wake regulation seems to be failed in depression, which also promotes the development of clinical depression. Also, REM sleep alterations have been considered as biomarkers of depression. The disturbances of norepinephrine and serotonin systems may contribute to REM sleep abnormalities in depression. Lastly, this review also discusses the effects of different antidepressants on REM sleep disturbances in depression. PMID:26412074

  8. Cerebral sympathetic nerve activity has a major regulatory role in the cerebral circulation in REM sleep.

    PubMed

    Cassaglia, Priscila A; Griffiths, Robert I; Walker, Adrian M

    2009-04-01

    Sympathetic nerve activity (SNA) in neurons projecting to skeletal muscle blood vessels increases during rapid-eye-movement (REM) sleep, substantially exceeding SNA of non-REM (NREM) sleep and quiet wakefulness (QW). Similar SNA increases to cerebral blood vessels may regulate the cerebral circulation in REM sleep, but this is unknown. We hypothesized that cerebral SNA increases during phasic REM sleep, constricting cerebral vessels as a protective mechanism against cerebral hyperperfusion during the large arterial pressure surges that characterize this sleep state. We tested this hypothesis using a newly developed model to continuously record SNA in the superior cervical ganglion (SCG) before, during, and after arterial pressure surges occurring during REM in spontaneously sleeping lambs. Arterial pressure (AP), intracranial pressure (ICP), cerebral blood flow (CBF), cerebral vascular resistance [CVR = (AP - ICP)/CBF], and SNA from the SCG were recorded in lambs (n = 5) undergoing spontaneous sleep-wake cycles. In REM sleep, CBF was greatest (REM > QW = NREM, P < 0.05) and CVR was least (REM < QW = NREM, P < 0.05). SNA in the SCG did not change from QW to NREM sleep but increased during tonic REM sleep, with a further increase during phasic REM sleep (phasic REM > tonic REM > QW = NREM, P < 0.05). Coherent averaging revealed that SNA increases preceded AP surges in phasic REM sleep by 12 s (P < 0.05). We report the first recordings of cerebral SNA during natural sleep-wake cycles. SNA increases markedly during tonic REM sleep, and further in phasic REM sleep. As SNA increases precede AP surges, they may serve to protect the brain against potentially damaging intravascular pressure changes or hyperperfusion in REM sleep.

  9. Digital Receiver Phase Meter

    NASA Technical Reports Server (NTRS)

    Marcin, Martin; Abramovici, Alexander

    2008-01-01

    The software of a commercially available digital radio receiver has been modified to make the receiver function as a two-channel low-noise phase meter. This phase meter is a prototype in the continuing development of a phase meter for a system in which radiofrequency (RF) signals in the two channels would be outputs of a spaceborne heterodyne laser interferometer for detecting gravitational waves. The frequencies of the signals could include a common Doppler-shift component of as much as 15 MHz. The phase meter is required to measure the relative phases of the signals in the two channels at a sampling rate of 10 Hz at a root power spectral density <5 microcycle/(Hz)1/2 and to be capable of determining the power spectral density of the phase difference over the frequency range from 1 mHz to 1 Hz. Such a phase meter could also be used on Earth to perform similar measurements in laser metrology of moving bodies. To illustrate part of the principle of operation of the phase meter, the figure includes a simplified block diagram of a basic singlechannel digital receiver. The input RF signal is first fed to the input terminal of an analog-to-digital converter (ADC). To prevent aliasing errors in the ADC, the sampling rate must be at least twice the input signal frequency. The sampling rate of the ADC is governed by a sampling clock, which also drives a digital local oscillator (DLO), which is a direct digital frequency synthesizer. The DLO produces samples of sine and cosine signals at a programmed tuning frequency. The sine and cosine samples are mixed with (that is, multiplied by) the samples from the ADC, then low-pass filtered to obtain in-phase (I) and quadrature (Q) signal components. A digital signal processor (DSP) computes the ratio between the Q and I components, computes the phase of the RF signal (relative to that of the DLO signal) as the arctangent of this ratio, and then averages successive such phase values over a time interval specified by the user.

  10. REM Restriction Persistently Alters Strategy Used to Solve a Spatial Task

    ERIC Educational Resources Information Center

    Bjorness, Theresa E.; Tysor, Michael K.; Poe, Gina R.; Riley, Brett T.

    2005-01-01

    We tested the hypothesis that rapid eye movement (REM) sleep is important for complex associative learning by restricting rats from entering REM sleep for 4 h either immediately after training on an eight-box spatial task (0-4 REMr) or 4 h following training (4-8 REMr). Both groups of REM-restricted rats eventually reached the same overall…

  11. Endogenous GABA levels in the pontine reticular formation are greater during wakefulness than during REM sleep

    PubMed Central

    Vanini, Giancarlo; Wathen, Bradley L.; Lydic, Ralph; Baghdoyan, Helen A.

    2011-01-01

    Studies using drugs that increase or decrease GABAergic transmission suggest that GABA in the pontine reticular formation (PRF) promotes wakefulness and inhibits rapid eye movement (REM) sleep. Cholinergic transmission in the PRF promotes REM sleep, and levels of endogenous acetylcholine (ACh) in the PRF are significantly greater during REM sleep than during wakefulness or non-REM (NREM) sleep. No previous studies have determined whether levels of endogenous GABA in the PRF vary as a function of sleep and wakefulness. This study tested the hypothesis that GABA levels in cat PRF are greatest during wakefulness and lowest during REM sleep. Extracellular GABA levels were measured during wakefulness, NREM sleep, REM sleep, and the REM sleep-like state (REMNeo) caused by microinjecting neostigmine into the PRF. GABA levels varied significantly as a function of sleep and wakefulness, and decreased significantly below waking levels during REM sleep (−42%) and REMNeo (−63%). The decrease in GABA levels during NREM sleep (22% below waking levels) was not statistically significant. Compared to NREM sleep, GABA levels decreased significantly during REM sleep (−27%) and REMNeo (−52%). Comparisons of REM sleep and REMNeo revealed no differences in GABA levels or cortical EEG power. GABA levels did not vary significantly as a function of dialysis site within the PRF. The inverse relationship between changes in PRF levels of GABA and ACh during REM sleep indicates that low GABAergic tone combined with high cholinergic tone in the PRF contributes to the generation of REM sleep. PMID:21325533

  12. Normative EMG Values during REM Sleep for the Diagnosis of REM Sleep Behavior Disorder

    PubMed Central

    Frauscher, Birgit; Iranzo, Alex; Gaig, Carles; Gschliesser, Viola; Guaita, Marc; Raffelseder, Verena; Ehrmann, Laura; Sola, Nuria; Salamero, Manel; Tolosa, Eduardo; Poewe, Werner; Santamaria, Joan; Högl, Birgit

    2012-01-01

    a cutoff of 32%, when using 3-sec miniepochs. Citation: Frauscher B; Iranzo A; Gaig C; Gschliesser V; Guaita M; Raffelseder V; Ehrmann L; Sola N; Salamero M; Tolosa E; Poewe W; Santamaria J; Högl B. Normative EMG values during REM sleep for the diagnosis of REM sleep behavior disorder. SLEEP 2012;35(6):835-847. PMID:22654203

  13. Management of REM sleep behavior disorder: An evidence based review

    PubMed Central

    Devnani, Preeti; Fernandes, Racheal

    2015-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by dream enactment behavior resulting from a loss of REM skeletal muscle atonia. The neurobiology of REM sleep and the characteristic features of REM atonia have an important basis for understanding the aggravating etiologies the proposed pharmacological interventions in its management. This review outlines the evidence for behavioral and therapeutic measures along with evidence-based guidelines for their implementation, impact on falls, and effect on polysomnography (PSG) while highlighting the non-motor, autonomic, and cognitive impact of this entity. PubMed databases were reviewed upto May 2013 in peer-reviewed scientific literature regarding the pathophysiology and management of RBD in adults. The literature was graded according to the Oxford centre of evidence-based Medicine Levels. An early intervention that helps prevent consequences such as falls and provides a base for intervention with neuroprotective mechanisms and allocates a unique platform that RBD portrays with its high risk of disease conversion with a sufficiently long latency. RBD provides a unique platform with its high risk of disease conversion with a sufficiently long latency, providing an opportunity for early intervention both to prevent consequences such as falls and provide a base for intervention with neuroprotective mechanisms. PMID:25745301

  14. Video analysis of motor events in REM sleep behavior disorder.

    PubMed

    Frauscher, Birgit; Gschliesser, Viola; Brandauer, Elisabeth; Ulmer, Hanno; Peralta, Cecilia M; Müller, Jörg; Poewe, Werner; Högl, Birgit

    2007-07-30

    In REM sleep behavior disorder (RBD), several studies focused on electromyographic characterization of motor activity, whereas video analysis has remained more general. The aim of this study was to undertake a detailed and systematic video analysis. Nine polysomnographic records from 5 Parkinson patients with RBD were analyzed and compared with sex- and age-matched controls. Each motor event in the video during REM sleep was classified according to duration, type of movement, and topographical distribution. In RBD, a mean of 54 +/- 23.2 events/10 minutes of REM sleep (total 1392) were identified and visually analyzed. Seventy-five percent of all motor events lasted <2 seconds. Of these events, 1,155 (83.0%) were classified as elementary, 188 (13.5%) as complex behaviors, 50 (3.6%) as violent, and 146 (10.5%) as vocalizations. In the control group, 3.6 +/- 2.3 events/10 minutes (total 264) of predominantly elementary simple character (n = 240, 90.9%) were identified. Number and types of motor events differed significantly between patients and controls (P < 0.05). This study shows a very high number and great variety of motor events during REM sleep in symptomatic RBD. However, most motor events are minor, and violent episodes represent only a small fraction.

  15. REM sleep behavior disorder: from dreams to neurodegeneration.

    PubMed

    Postuma, Ronald B; Gagnon, Jean-Francois; Montplaisir, Jacques Y

    2012-06-01

    REM sleep behavior disorder is a unique parasomnia characterized by dream enactment behavior during REM sleep. Unless triggered by pharmacologic agents such as antidepressants, it is generally related to damage of pontomedullary brainstem structures. Idiopathic REM sleep behavior disorder (RBD) is a well-established risk factor for neurodegenerative disease. Prospective studies have estimated that at least 40-65% of patients with idiopathic RBD will eventually develop a defined neurodegenerative phenotype, almost always a 'synucleinopathy' (Parkinson's disease, Lewy Body dementia or multiple system atrophy). In most cases, patients appear to develop a syndrome with overlapping features of both Parkinson's disease and Lewy body dementia. The interval between RBD onset and disease onset averages 10-15 years, suggesting a promisingly large window for intervention into preclinical disease stages. The ability of RBD to predict disease has major implications for design and development of neuroprotective therapy, and testing of other predictive markers of synuclein-mediated neurodegeneration. Recent studies in idiopathic RBD patients have demonstrated that olfaction, color vision, severity of REM atonia loss, transcranial ultrasound of the substantia nigra, and dopaminergic neuroimaging can predict development of neurodegenerative disease.

  16. Characterization of neutron calibration fields at the TINT's 50 Ci americium-241/beryllium neutron irradiator

    NASA Astrophysics Data System (ADS)

    Liamsuwan, T.; Channuie, J.; Ratanatongchai, W.

    2015-05-01

    Reliable measurement of neutron radiation is important for monitoring and protection in workplace where neutrons are present. Although Thailand has been familiar with applications of neutron sources and neutron beams for many decades, there is no calibration facility dedicated to neutron measuring devices available in the country. Recently, Thailand Institute of Nuclear Technology (TINT) has set up a multi-purpose irradiation facility equipped with a 50 Ci americium-241/beryllium neutron irradiator. The facility is planned to be used for research, nuclear analytical techniques and, among other applications, calibration of neutron measuring devices. In this work, the neutron calibration fields were investigated in terms of neutron energy spectra and dose equivalent rates using Monte Carlo simulations, an in-house developed neutron spectrometer and commercial survey meters. The characterized neutron fields can generate neutron dose equivalent rates ranging from 156 μSv/h to 3.5 mSv/h with nearly 100% of dose contributed by neutrons of energies larger than 0.01 MeV. The gamma contamination was less than 4.2-7.5% depending on the irradiation configuration. It is possible to use the described neutron fields for calibration test and routine quality assurance of neutron dose rate meters and passive dosemeters commonly used in radiation protection dosimetry.

  17. Simple Schlieren Light Meter

    NASA Technical Reports Server (NTRS)

    Rhodes, David B.; Franke, John M.; Jones, Stephen B.; Leighty, Bradley D.

    1992-01-01

    Simple light-meter circuit used to position knife edge of schlieren optical system to block exactly half light. Enables operator to check quickly position of knife edge between tunnel runs to ascertain whether or not in alignment. Permanent measuring system made part of each schlieren system. If placed in unused area of image plane, or in monitoring beam from mirror knife edge, provides real-time assessment of alignment of schlieren system.

  18. Ride quality meter

    NASA Technical Reports Server (NTRS)

    Leatherwood, J. D.; Dempsey, T. K.; Clevenson, S. A.; Stephens, D. G. (Inventor)

    1983-01-01

    A ride quality meter is disclosed that automatically transforms vibration and noise measurements into a single number index of passenger discomfort. The noise measurements are converted into a noise discomfort value. The vibrations are converted into single axis discomfort values which are then converted into a combined axis discomfort value. The combined axis discomfort value is corrected for time duration and then summed with the noise discomfort value to obtain a total discomfort value.

  19. Hand-Strength Meter

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Elliot, Joe

    1987-01-01

    Special grip-strength meter designed for accurate, reproducible measurement of hand rehabilitation. Four strain gauges connected in Wheatstone bridge to measure deflection caused by gripping hand. Compressive force exerted by hand transmitted to measuring beams. Beams therefore deflected or strained, and mechanical strain sensed by strain gauges and converted into electrical signal. After amplification and conditioning, signal displayed on LED as measure of gripping strength of hand.

  20. Period meter for reactors

    DOEpatents

    Rusch, Gordon K.

    1976-01-06

    An improved log N amplifier type nuclear reactor period meter with reduced probability for noise-induced scrams is provided. With the reactor at low power levels a sampling circuit is provided to determine the reactor period by measuring the finite change in the amplitude of the log N amplifier output signal for a predetermined time period, while at high power levels, differentiation of the log N amplifier output signal provides an additional measure of the reactor period.

  1. Characteristics of REM Sleep Behavior Disorder in Childhood

    PubMed Central

    Lloyd, Robin; Tippmann-Peikert, Maja; Slocumb, Nancy; Kotagal, Suresh

    2012-01-01

    Study Objective: To describe our experience regarding the clinical and polysomnographic features of REM sleep behavior disorder (RBD) in childhood. Methods: This was a retrospective chart review of children and adolescents with RBD and REM sleep without atonia. Demographics, and clinical and polysomnographic information were tabulated. Our findings were compared with those in the existing literature. Results: The 15 subjects identified (13 RBD and 2 having REM sleep without atonia) had a mean age at diagnosis of 9.5 years (range 3-17 years); 11/15 (73%) were male. Nightmares were reported in 13/15 and excessive daytime sleepiness in 6/15. Two children had caused bodily harm to bedmate siblings. Comorbidities, which were multiple in some subjects, included anxiety (8/15), attention deficit disorder (10/15), nonspecific developmental delay (6/15), Smith-Magenis syndrome (1/15), pervasive developmental disorder (1/15), narcolepsy (1/15), idiopathic hypersomnia (1/15), and Moebius Syndrome (1/15). Abnormal MRI scans were seen in 5/8 evaluated subjects. Treatments consisted of clonazepam (10/15), melatonin (2/15), and discontinuation of a tricyclic agent (1/15), with a favorable response in 11 of 13. Two of 15 patients with REM sleep without atonia did not require pharmacotherapy. Conclusions: RBD in children may be associated with neurodevelopmental disabilities, narcolepsy, or medication use. It seems to be modestly responsive to benzodiazepines or melatonin. The etiology is distinct from that of common childhood arousal parasomnias and RBD in adults; congenital and neurodevelopmental disorders, medication effect, and narcolepsy coexisted in some, but none had an extrapyramidal neurodegenerative disorder. Citation: Lloyd R; Tippmann-Peikert M; Slocumb N; Kotagal S. Characteristics of REM sleep behavior disorder in childhood. J Clin Sleep Med 2012;8(2):127-131. PMID:22505856

  2. Morning REM Sleep Naps Facilitate Broad Access to Emotional Semantic Networks

    PubMed Central

    Carr, Michelle; Nielsen, Tore

    2015-01-01

    Study Objectives: The goals of the study were to assess semantic priming to emotion and nonemotion cue words using a novel measure of associational breadth for participants who either took rapid eye movement (REM) or nonrapid eye movement (NREM) naps or who remained awake, and to assess the relation of priming to REM sleep consolidation and REM sleep inertia effects. Design: The associational breadth task was applied in both a priming condition, where cue words were signaled to be memorized prior to sleep (primed), and a nonpriming condition, where cue words were not memorized (nonprimed). Cue words were either emotional (positive, negative) or nonemotional. Participants were randomly assigned to either an awake (WAKE) or a sleep condition, which was subsequently split into NREM or REM groups depending on stage at awakening. Setting: Hospital-based sleep laboratory. Participants: Fifty-eight healthy participants (22 male) ages 18 to 35 y (mean age = 23.3 ± 4.08 y). Measurements and Results: The REM group scored higher than the NREM or WAKE groups on primed, but not nonprimed emotional cue words; the effect was stronger for positive than for negative cue words. However, REM time and percent correlated negatively with degree of emotional priming. Priming occurred for REM awakenings but not for NREM awakenings, even when the latter sleep episodes contained some REM sleep. Conclusions: Associational breadth may be selectively consolidated during REM sleep for stimuli that have been tagged as important for future memory retrieval. That priming decreased with REM time and was higher only for REM sleep awakenings is consistent with two explanatory REM sleep processes: REM sleep consolidation serving emotional downregulation and REM sleep inertia. Citation: Carr M, Nielsen T. Morning REM sleep naps facilitate broad access to emotional semantic networks. SLEEP 2015;38(3):433–443. PMID:25409100

  3. 77 FR 40586 - Draft NIST Interagency Report (NISTIR) 7823, Advanced Metering Infrastructure Smart Meter...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-10

    ... Metering Infrastructure Smart Meter Upgradeability Test Framework; Request for Comments AGENCY: National... Metering Infrastructure Smart Meter Upgradeability Test Framework (Draft NISTIR 7823). This draft document... process for the Advanced Metering Infrastructure (AMI) Smart Meters. The target audience for Draft...

  4. A review of mentation in REM and NREM sleep: "covert" REM sleep as a possible reconciliation of two opposing models.

    PubMed

    Nielsen, T A

    2000-12-01

    Numerous studies have replicated the finding of mentation in both rapid eye movement (REM) and nonrapid eye movement (NREM) sleep. However, two different theoretical models have been proposed to account for this finding: (1) a one-generator model, in which mentation is generated by a single set of processes regardless of physiological differences between REM and NREM sleep; and (2) a two-generator model, in which qualitatively different generators produce cognitive activity in the two states. First, research is reviewed demonstrating conclusively that mentation can occur in NREM sleep; global estimates show an average mentation recall rate of about 50% from NREM sleep--a value that has increased substantially over the years. Second, nine different types of research on REM and NREM cognitive activity are examined for evidence supporting or refuting the two models. The evidence largely, but not completely, favors the two-generator model. Finally, in a preliminary attempt to reconcile the two models, an alternative model is proposed that assumes the existence of covert REM sleep processes during NREM sleep. Such covert activity may be responsible for much of the dreamlike cognitive activity occurring in NREM sleep.

  5. Evaluating the Evidence Surrounding Pontine Cholinergic Involvement in REM Sleep Generation

    PubMed Central

    Grace, Kevin P.; Horner, Richard L.

    2015-01-01

    Rapid eye movement (REM) sleep – characterized by vivid dreaming, motor paralysis, and heightened neural activity – is one of the fundamental states of the mammalian central nervous system. Initial theories of REM sleep generation posited that induction of the state required activation of the “pontine REM sleep generator” by cholinergic inputs. Here, we review and evaluate the evidence surrounding cholinergic involvement in REM sleep generation. We submit that: (i) the capacity of pontine cholinergic neurotransmission to generate REM sleep has been firmly established by gain-of-function experiments, (ii) the function of endogenous cholinergic input to REM sleep generating sites cannot be determined by gain-of-function experiments; rather, loss-of-function studies are required, (iii) loss-of-function studies show that endogenous cholinergic input to the PTF is not required for REM sleep generation, and (iv) cholinergic input to the pontine REM sleep generating sites serve an accessory role in REM sleep generation: reinforcing non-REM-to-REM sleep transitions making them quicker and less likely to fail. PMID:26388832

  6. Acoustic velocity meter systems

    USGS Publications Warehouse

    Laenen, Antonius

    1985-01-01

    Acoustic velocity meter (AVM) systems operate on the principles that the point-to-point upstream traveltime of an acoustic pulse is longer than the downstream traveltime and that this difference in traveltime can be accurately measured by electronic devices. An AVM system is capable of recording water velocity (and discharge) under a wide range of conditions, but some constraints apply: 1. Accuracy is reduced and performance is degraded if the acoustic path is not a continuous straight line. The path can be bent by reflection if it is too close to a stream boundary or by refraction if it passes through density gradients resulting from variations in either water temperature or salinity. For paths of less than 100 m, a temperature gradient of 0.1' per meter causes signal bending less than 0.6 meter at midchannel, and satisfactory velocity results can be obtained. Reflection from stream boundaries can cause signal cancellation if boundaries are too close to signal path. 2. Signal strength is attenuated by particles or bubbles that absorb, spread, or scatter sound. The concentration of particles or bubbles that can be tolerated is a function of the path length and frequency of the acoustic signal. 3. Changes in streamline orientation can affect system accuracy if the variability is random. 4. Errors relating to signal resolution are much larger for a single threshold detection scheme than for multiple threshold schemes. This report provides methods for computing the effect of various conditions on the accuracy of a record obtained from an AVM. The equipment must be adapted to the site. Field reconnaissance and preinstallation analysis to detect possible problems are critical for proper installation and operation of an AVM system.

  7. REM sleep selectively prunes and maintains new synapses in development and learning.

    PubMed

    Li, Wei; Ma, Lei; Yang, Guang; Gan, Wen-Biao

    2017-03-01

    The functions and underlying mechanisms of rapid eye movement (REM) sleep remain unclear. Here we show that REM sleep prunes newly formed postsynaptic dendritic spines of layer 5 pyramidal neurons in the mouse motor cortex during development and motor learning. This REM sleep-dependent elimination of new spines facilitates subsequent spine formation during development and when a new motor task is learned, indicating a role for REM sleep in pruning to balance the number of new spines formed over time. Moreover, REM sleep also strengthens and maintains newly formed spines, which are critical for neuronal circuit development and behavioral improvement after learning. We further show that dendritic calcium spikes arising during REM sleep are important for pruning and strengthening new spines. Together, these findings indicate that REM sleep has multifaceted functions in brain development, learning and memory consolidation by selectively eliminating and maintaining newly formed synapses via dendritic calcium spike-dependent mechanisms.

  8. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1999-02-02

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  9. Portable wastewater flow meter

    DOEpatents

    Hunter, Robert M.

    1990-01-01

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  10. Direct reading inductance meter

    NASA Technical Reports Server (NTRS)

    Kolby, R. B. (Inventor)

    1977-01-01

    A direct reading inductance meter comprised of a crystal oscillator and an LC tuned oscillator is presented. The oscillators function respectively to generate a reference frequency, f(r), and to generate an initial frequency, f(0), which when mixed produce a difference equal to zero. Upon connecting an inductor of small unknown value in the LC circuit to change its resonant frequency to f(x), a difference frequency (f(r)-f(x)) is produced that is very nearly a linear function of the inductance of the inductor. The difference frequency is measured and displayed on a linear scale in units of inductance.

  11. REM sleep diversity following the pedunculopontine tegmental nucleus lesion in rat.

    PubMed

    Petrovic, Jelena; Lazic, Katarina; Kalauzi, Aleksandar; Saponjic, Jasna

    2014-09-01

    The aim of this study was to demonstrate that two REM clusters, which emerge following bilateral pedunculopontine tegmental nucleus (PPT) lesions in rats, are two functionally distinct REM states. We performed the experiments in Wistar rats, chronically instrumented for sleep recording. Bilateral PPT lesions were produced by the microinfusion of 100 nl of 0.1M ibotenic acid (IBO). Following a recovery period of 2 weeks, we recorded their sleep for 6h. Bilateral PPT lesions were identified by NADPH - diaphorase histochemistry. We applied Fourier analysis to the signals acquired throughout the 6h recordings, and each 10s epoch was differentiated as a Wake, NREM or REM state. We analyzed the topography of the sleep/wake states architecture and their transition structure, their all state-related EEG microstructures, and the sensorimotor (SMCx) and motor (MCx) cortex REM related cortico-muscular coherences (CMCs). Bilateral PPT lesion in rats increased the likelihood of the emergence of two distinct REM sleep states, specifically expressed within the MCx: REM1 and REM2. Bilateral PPT lesion did not change the sleep/wake states architecture of the SMCx, but pathologically increased the duration of REM1 within the MCx, alongside increasing Wake/REM1/Wake and NREM/REM2/NREM transitions within both cortices. In addition, the augmented total REM SMCx EEG beta amplitude and REM1 MCx EEG theta amplitude was the underlying EEG microstructure pathology. PPT lesion induced REM1 and REM2 are differential states with regard to total EMG power, topographically distinct EEG microstructures, and locomotor drives to nuchal musculature.

  12. Turbine meters for liquid measurement

    SciTech Connect

    Wass, D.J.; Allen, C.R.

    1995-12-01

    Liquid turbine meters operate in response to fundamental engineering principles, Operation with a single moving part produces excellent longevity and reliability. Liquid turbine meters display wide rangeability, high accuracy, excellent repeatability, low pressure drop and moderate cost. Liquid turbine meters may be applied to many different fluids with different physical properties and corrosive tendencies. The marriage of liquid turbine meters to electronic instruments allows instantaneous flow calculations and produces the flexibility to display data, store data, transmit data in the most convenient form. Liquid turbine meters should be the first flow measurement instrument considered for liquid measurement applications.

  13. Plant chlorophyll content meter

    NASA Technical Reports Server (NTRS)

    Spiering, Bruce A. (Inventor); Carter, Gregory A. (Inventor)

    2000-01-01

    A plant chlorophyll content meter is described which collects light reflected from a target plant and separates the collected light into two different wavelength bands. These wavelength bands, or channels, are described as having center wavelengths of 700 nm and 840 nm. The light collected in these two channels are processed using photo detectors and amplifiers. An analog to digital converter is described which provides a digital representation of the level of light collected by the lens and falling within the two channels. A controller provided in the meter device compares the level of light reflected from a target plant with a level of light detected from a light source, such as light reflected by a target having 100% reflectance, or transmitted through a diffusion receptor. The percent of reflection in the two separate wavelength bands from a target plant are compared to provide a ratio which indicates a relative level of plant physiological stress. A method of compensating for electronic drift is described where a sample is taken when a collection lens is covered to prevent light from entering the device. This compensation method allows for a more accurate reading by reducing error contributions due to electronic drift from environmental conditions at the location where a hand-held unit is used.

  14. Advanced metering techniques

    SciTech Connect

    Szydlowski, R.F.

    1993-01-01

    The goal of the US Department of Energy Federal Energy Management Program (FEMP) is to facilitate energy-efficiency improvements at federal facilities. This is accomplished by a balanced program of technology development, facility assessment, and use of cost-sharing procurement mechanisms. Technology development focuses upon the tools and procedures used to identify and evaluate efficiency improvements. For facility assessment, FEMP provides metering equipment and trained analysts to federal agencies exhibiting a commitment to improve energy-use efficiency. To assist in implementing energy-efficiency measures, FEMP helps federal agencies with identifying efficiency opportunities and in implementing energy-efficiency and demand-side management programs at federal sites. As the lead laboratory for FEMP, Pacific Northwest Laboratory (PNL) provides technical assistance to federal agencies to better understand and characterize energy systems. The US Army Forces Command (FORSCOM) has tasked PNL to provide technical assistance to characterize and modernize energy systems at FORSCOM installations. As part of that technical assistance, PNL performed an in-depth examination of automatic meter-reading system technologies currently available. The operating characteristics and relative merits of all the major systems were reviewed in the context of applicability to federal installations. That review is documented in this report.

  15. 10 meter airborne observatory

    NASA Astrophysics Data System (ADS)

    Ditto, Thomas D.; Ritter, Joseph M.

    2008-07-01

    Inside an aircraft fuselage there is little room for the mass of all the instrumentation of a ground-based observatory much less a primary objective aperture at the scale of 10 meters. We have proposed a solution that uses a primary objective grating (POG) which matches the considerable length of the aircraft, approximately 10 meters, and conforms to aircraft aerodynamics. Light collected by the POG is diffracted at an angle of grazing exodus inside the aircraft where it is disambiguated by an optical train that fits within to the interior tunnel. Inside the aircraft, light is focused by a parabolic mirror onto a spectrograph slit. The design has a special benefit in that all objects in the field-of-view of the free spectral range of the POG can have their spectra taken as the aircraft changes orientation. We suggest flight planes that will improve integration times, angular resolution and spectral resolution to acquire targets of high stellar magnitudes or alternatively increase the number of sources acquired per flight at the cost of sensitivity.

  16. REM sleep and dreaming: towards a theory of protoconsciousness.

    PubMed

    Hobson, J Allan

    2009-11-01

    Dreaming has fascinated and mystified humankind for ages: the bizarre and evanescent qualities of dreams have invited boundless speculation about their origin, meaning and purpose. For most of the twentieth century, scientific dream theories were mainly psychological. Since the discovery of rapid eye movement (REM) sleep, the neural underpinnings of dreaming have become increasingly well understood, and it is now possible to complement the details of these brain mechanisms with a theory of consciousness that is derived from the study of dreaming. The theory advanced here emphasizes data that suggest that REM sleep may constitute a protoconscious state, providing a virtual reality model of the world that is of functional use to the development and maintenance of waking consciousness.

  17. Relabeling exchange method (REM) for learning in neural networks

    NASA Astrophysics Data System (ADS)

    Wu, Wen; Mammone, Richard J.

    1994-02-01

    The supervised training of neural networks require the use of output labels which are usually arbitrarily assigned. In this paper it is shown that there is a significant difference in the rms error of learning when `optimal' label assignment schemes are used. We have investigated two efficient random search algorithms to solve the relabeling problem: the simulated annealing and the genetic algorithm. However, we found them to be computationally expensive. Therefore we shall introduce a new heuristic algorithm called the Relabeling Exchange Method (REM) which is computationally more attractive and produces optimal performance. REM has been used to organize the optimal structure for multi-layered perceptrons and neural tree networks. The method is a general one and can be implemented as a modification to standard training algorithms. The motivation of the new relabeling strategy is based on the present interpretation of dyslexia as an encoding problem.

  18. Spartan Release Engagement Mechanism (REM) stress and fracture analysis

    NASA Technical Reports Server (NTRS)

    Marlowe, D. S.; West, E. J.

    1984-01-01

    The revised stress and fracture analysis of the Spartan REM hardware for current load conditions and mass properties is presented. The stress analysis was performed using a NASTRAN math model of the Spartan REM adapter, base, and payload. Appendix A contains the material properties, loads, and stress analysis of the hardware. The computer output and model description are in Appendix B. Factors of safety used in the stress analysis were 1.4 on tested items and 2.0 on all other items. Fracture analysis of the items considered fracture critical was accomplished using the MSFC Crack Growth Analysis code. Loads and stresses were obtaind from the stress analysis. The fracture analysis notes are located in Appendix A and the computer output in Appendix B. All items analyzed met design and fracture criteria.

  19. Schema-conformant memories are preferentially consolidated during REM sleep.

    PubMed

    Durrant, Simon J; Cairney, Scott A; McDermott, Cathal; Lewis, Penelope A

    2015-07-01

    Memory consolidation is most commonly described by the standard model, which proposes an initial binding role for the hippocampus which diminishes over time as intracortical connections are strengthened. Recent evidence suggests that slow wave sleep (SWS) plays an essential role in this process. Existing animal and human studies have suggested that memories which fit tightly into an existing knowledge framework or schema might use an alternative consolidation route in which the medial prefrontal cortex takes on the binding role. In this study we sought to investigate the role of sleep in this process using a novel melodic memory task. Participants were asked to remember 32 melodies, half of which conformed to a tonal schema present in all enculturated listeners, and half of which did not fit with this schema. After a 24-h consolidation interval, participants were asked to remember a further 32 melodies, before being given a recognition test in which melodies from both sessions were presented alongside some previously unheard foils. Participants remembered schema-conformant melodies better than non-conformant ones. This was much more strongly the case for consolidated melodies, suggesting that consolidation over a 24-h period preferentially consolidated schema-conformant items. Overnight sleep was monitored between the sessions, and the extent of the consolidation benefit for schema-conformant items was associated with both the amount of REM sleep obtained and EEG theta power in frontal and central regions during REM sleep. Overall our data suggest that REM sleep plays a crucial role in the rapid consolidation of schema-conformant items. This finding is consistent with previous results from animal studies and the SLIMM model of Van Kesteren, Ruiter, Fernández, and Henson (2012), and suggest that REM sleep, rather than SWS, may be involved in an alternative pathway of consolidation for schema-conformant memories.

  20. CHRONICLE: In memory of Rem Viktorovich Khokhlov (1926-1977)

    NASA Astrophysics Data System (ADS)

    Kravtsov, Nikolai V.; Polkovnikov, Boris F.

    1996-12-01

    A review is presented of the memorial events at the M.V.Lomonosov Moscow State University held on the seventieth anniversary of the birth of Rem Viktorovich Khokhlov (1926-1977). The events, which took place in the week of 14-19 October, included a Nobel Lecture-hall, Khokhlov Memorial Lectures, a Conference of Young Scientists, and a session of the R.V. Khokhlov Higher Laser School (Khokhlov Tutorials).

  1. On the 90th Birthday of Rem Viktorovich Khokhlov

    NASA Astrophysics Data System (ADS)

    Makarov, V. A.

    2016-08-01

    July 15th 2016 marked the 90th birthday of Rem Viktorovich Khokhlov, a prominent Russian physicist, talented organiser of national and world science and higher education, rector of Lomonosov Moscow State University, vice-president of the USSR Academy of Sciences, founder and head of the Department of Wave Processes. He tragically died on 8 August 1977 trying to conquer the highest peak of the Pamir Mountains.

  2. REM sleep modulation by perifornical orexinergic inputs to the pedunculo-pontine tegmental neurons in rats.

    PubMed

    Khanday, M A; Mallick, B N

    2015-11-12

    Rapid eye movement sleep (REMS) is regulated by the interaction of the REM-ON and REM-OFF neurons located in the pedunculo-pontine-tegmentum (PPT) and the locus coeruleus (LC), respectively. Many other brain areas, particularly those controlling non-REMS (NREMS) and waking, modulate REMS by modulating these REMS-related neurons. Perifornical (PeF) orexin (Ox)-ergic neurons are reported to increase waking and reduce NREMS as well as REMS; dysfunction of the PeF neurons are related to REMS loss-associated disorders. Hence, we were interested in understanding the neural mechanism of PeF-induced REMS modulation. As a first step we have recently reported that PeF Ox-ergic neurons modulate REMS by influencing the LC neurons (site for REM-OFF neurons). Thereafter, in this in vivo study we have explored the role of PeF inputs on the PPT neurons (site for REM-ON neurons) for the regulation of REMS. Chronic male rats were surgically prepared with implanted bilateral cannulae in PeF and PPT and electrodes for recording sleep-waking patterns. After post-surgical recovery sleep-waking-REMS were recorded when bilateral PeF neurons were stimulated by glutamate and simultaneously bilateral PPT neurons were infused with either saline or orexin receptor1 (OX1R) antagonist. It was observed that PeF stimulation increased waking and decreased NREMS as well as REMS, which were prevented by OX1R antagonist into the PPT. We conclude that the PeF stimulation-induced reduction in REMS was likely to be due to inhibition of REM-ON neurons in the PPT. As waking and NREMS are inversely related, subject to confirmation, the reduction in NREMS could be due to increased waking or vice versa. Based on our findings from this and earlier studies we have proposed a model showing connections between PeF- and PPT-neurons for REMS regulation.

  3. Frontal beta-theta network during REM sleep

    PubMed Central

    Vijayan, Sujith; Lepage, Kyle Q; Kopell, Nancy J; Cash, Sydney S

    2017-01-01

    We lack detailed knowledge about the spatio-temporal physiological signatures of REM sleep, especially in humans. By analyzing intracranial electrode data from humans, we demonstrate for the first time that there are prominent beta (15–35 Hz) and theta (4–8 Hz) oscillations in both the anterior cingulate cortex (ACC) and the DLPFC during REM sleep. We further show that these theta and beta activities in the ACC and the DLPFC, two relatively distant but reciprocally connected regions, are coherent. These findings suggest that, counter to current prevailing thought, the DLPFC is active during REM sleep and likely interacting with other areas. Since the DLPFC and the ACC are implicated in memory and emotional regulation, and the ACC has motor areas and is thought to be important for error detection, the dialogue between these two areas could play a role in the regulation of emotions and in procedural motor and emotional memory consolidation. DOI: http://dx.doi.org/10.7554/eLife.18894.001 PMID:28121613

  4. ROS2: a multichannel vision for the robotic REM telescope

    NASA Astrophysics Data System (ADS)

    Molinari, Emilio; Covino, Stefano; Crimi, Giuseppe; D'Alessio, Francesco; Incorvaia, Salvatore; Fugazza, Dino; Spanò, Paolo; Toso, Giorgio; Tresoldi, Daniela; Vitali, Fabrizio

    2014-07-01

    During 2013, a new visible camera has been finally installed and tested at the 60cm, robotic REM telescope in the la Silla Observatory. REM is an Italian, fast-reacting telescope initially designed and built for the immediate response to GRB automatic alerts, but since the first light in 2003 its usage has been covering a wider range of astronomical interests. While the IR camera REMIR was reaching the expected limiting magnitudes, the original ROSS visible camera suffered, since the beginning, of a rather poor performance. We set therefore to implement a newer optical camera, leading to the design, tests and integration of ROS2, a dichroic-based four channels imaging camera. The four Sloan-like pass bands are imaged, at the same time, in four quadrants of the CCD, an Andor multilevel Peltier detector. The tests during the science commissioning show an impressive improvement in the limiting magnitudes, reaching two magnitudes fainter than ROSS. Here we show the concept, the tests and the user level product we are now offering at REM.

  5. REM sleep behavior disorder: motor manifestations and pathophysiology.

    PubMed

    Arnulf, Isabelle

    2012-05-01

    Patients with REM sleep behavior disorder (RBD) enact violent dreams during REM sleep in the absence of normal muscle atonia. This disorder is highly frequent in patients with synucleinopathies (60%-100% of patients) and rare in patients with other neurodegenerative disorders. The disorder is detected by interview plus video and sleep monitoring. Abnormal movements expose the patients and bed partners to a high risk of injury and sleep disruption. The disorder is usually alleviated with melatonin and clonazepam. Limb movements are mainly minor, jerky, fast, pseudohallucinatory, and repeated, with a limp wrist during apparently grasping movements, although body jerks and complex violent (fights) and nonviolent culturally acquired behaviors are also observed. Notably, parkinsonism disappears during RBD-associated complex behaviors in patients with Parkinson's disease and with multiple system atrophy, suggesting that the upper motor stream bypasses the basal ganglia during REM sleep. Longitudinal studies show that idiopathic RBD predisposes patients to later develop Parkinson's disease, dementia with Lewy bodies, and, more rarely, multiple system atrophy, with a rate of conversion of 46% within 5 years. During this time window, patients concomitantly develop nonmotor signs (decreased olfaction and color vision, orthostatic hypotension, altered visuospatial abilities, increased harm avoidance) and have abnormal test results (decreased putamen dopamine uptake, slower EEG). Patients with idiopathic RBD have higher and faster risk for conversion to Parkinson's disease and dementia with Lewy bodies if abnormalities in dopamine transporter imaging, transcranial sonography, olfaction, and color vision are found at baseline. They constitute a highly specific target for testing neuroprotective agents.

  6. Microwave fluid flow meter

    DOEpatents

    Billeter, Thomas R.; Philipp, Lee D.; Schemmel, Richard R.

    1976-01-01

    A microwave fluid flow meter is described utilizing two spaced microwave sensors positioned along a fluid flow path. Each sensor includes a microwave cavity having a frequency of resonance dependent upon the static pressure of the fluid at the sensor locations. The resonant response of each cavity with respect to a variation in pressure of the monitored fluid is represented by a corresponding electrical output which can be calibrated into a direct pressure reading. The pressure drop between sensor locations is then correlated as a measure of fluid velocity. In the preferred embodiment the individual sensor cavities are strategically positioned outside the path of fluid flow and are designed to resonate in two distinct frequency modes yielding a measure of temperature as well as pressure. The temperature response can then be used in correcting for pressure responses of the microwave cavity encountered due to temperature fluctuations.

  7. GAS METERING PUMP

    DOEpatents

    George, C.M.

    1957-12-31

    A liquid piston gas pump is described, capable of pumping minute amounts of gas in accurately measurable quantities. The pump consists of a flanged cylindrical regulating chamber and a mercury filled bellows. Sealed to the ABSTRACTS regulating chamber is a value and having a gas inlet and outlet, the inlet being connected by a helical channel to the bellows. A gravity check valve is in the gas outlet, so the gas passes through the inlet and the helical channel to the bellows where the pumping action as well as the metering is accomplished by the actuation of the mercury filled bellows. The gas then flows through the check valve and outlet to any associated apparatus.

  8. Post-learning REM sleep deprivation impairs long-term memory: reversal by acute nicotine treatment.

    PubMed

    Aleisa, A M; Alzoubi, K H; Alkadhi, K A

    2011-07-15

    Rapid eye movement sleep deprivation (REM-SD) is associated with spatial learning and memory impairment. During REM-SD, an increase in nicotine consumption among habitual smokers and initiation of tobacco use by non-smokers have been reported. We have shown recently that nicotine treatment prevented learning and memory impairments associated with REM-SD. We now report the interactive effects of post-learning REM-SD and/or nicotine. The animals were first trained on the radial arm water maze (RAWM) task, then they were REM-sleep deprived using the modified multiple platform paradigm for 24h. During REM-SD period, the rats were injected with saline or nicotine (1mg/kg s.c. every 12h: a total of 3 injections). The animals were tested for long-term memory in the RAWM at the end of the REM-SD period. The 24h post-learning REM-SD significantly impaired long-term memory. However, nicotine treatment reversed the post-learning REM-SD-induced impairment of long-term memory. On the other hand, post-learning treatment of normal rats with nicotine for 24h enhanced long-term memory. These results indicate that post-learning acute nicotine treatment prevented the deleterious effect of REM-SD on cognitive abilities.

  9. Identification of the transmitter and receptor mechanisms responsible for REM sleep paralysis.

    PubMed

    Brooks, Patricia L; Peever, John H

    2012-07-18

    During REM sleep the CNS is intensely active, but the skeletal motor system is paradoxically forced into a state of muscle paralysis. The mechanisms that trigger REM sleep paralysis are a matter of intense debate. Two competing theories argue that it is caused by either active inhibition or reduced excitation of somatic motoneuron activity. Here, we identify the transmitter and receptor mechanisms that function to silence skeletal muscles during REM sleep. We used behavioral, electrophysiological, receptor pharmacology and neuroanatomical approaches to determine how trigeminal motoneurons and masseter muscles are switched off during REM sleep in rats. We show that a powerful GABA and glycine drive triggers REM paralysis by switching off motoneuron activity. This drive inhibits motoneurons by targeting both metabotropic GABA(B) and ionotropic GABA(A)/glycine receptors. REM paralysis is only reversed when motoneurons are cut off from GABA(B), GABA(A) and glycine receptor-mediated inhibition. Neither metabotropic nor ionotropic receptor mechanisms alone are sufficient for generating REM paralysis. These results demonstrate that multiple receptor mechanisms trigger REM sleep paralysis. Breakdown in normal REM inhibition may underlie common sleep motor pathologies such as REM sleep behavior disorder.

  10. Automatic detection of rapid eye movements (REMs): A machine learning approach

    PubMed Central

    Yetton, Benjamin D.; Niknazar, Mohammad; Duggan, Katherine A.; McDevitt, Elizabeth A.; Whitehurst, Lauren N.; Sattari, Negin; Mednick, Sara C.

    2017-01-01

    Background Rapid eye movements (REMs) are a defining feature of REM sleep. The number of discrete REMs over time, or REM density, has been investigated as a marker of clinical psychopathology and memory consolidation. However, human detection of REMs is a time-consuming and subjective process. Therefore, reliable, automated REM detection software is a valuable research tool. New method We developed an automatic REM detection algorithm combining a novel set of extracted features and the ‘AdaBoost’ classification algorithm to detect the presence of REMs in Electrooculogram data collected from the right and left outer canthi (ROC/LOC). Algorithm performance measures of Recall (percentage of REMs detected) and Precision (percentage of REMs detected that are true REMs) were calculated and compared to the gold standard of human detection by three expert sleep scorers. REM detection by four non-experts were also investigated and compared to expert raters and the algorithm. Results The algorithm performance (78.1% Recall, 82.6% Precision) surpassed that of the average (expert & non-expert) single human detection performance (76% Recall, 83% Precision). Agreement between non-experts (Cronbach Alpha = 0.65) is markedly lower than experts (Cronbach Alpha = 0.80). Comparison with existing method(s) By following reported methods, we implemented all previously published LOC and ROC based detection algorithms on our dataset. Our algorithm performance exceeded all others. Conclusions The automatic detection algorithm presented is a viable and efficient method of REM detection as it reliably matches the performance of human scorers and outperforms all other known LOC- and ROC-based detection algorithms. PMID:26642967

  11. Plutonium Detection with Straw Neutron Detectors

    SciTech Connect

    Mukhopadhyay, Sanjoy; Maurer, Richard; Guss, Paul

    2014-03-27

    A kilogram of weapons grade plutonium gives off about 56,000 neutrons per second of which 55,000 neutrons come from spontaneous fission of 240Pu (~6% by weight of the total plutonium). Actually, all even numbered isotopes (238Pu, 240Pu, and 242Pu) produce copious spontaneous fission neutrons. These neutrons induce fission in the surrounding fissile 239Pu with an approximate multiplication of a factor of ~1.9. This multiplication depends on the shape of the fissile materials and the surrounding material. These neutrons (typically of energy 2 MeV and air scattering mean free path >100 meters) can be detected 100 meters away from the source by vehicle-portable neutron detectors. [1] In our current studies on neutron detection techniques, without using 3He gas proportional counters, we designed and developed a portable high-efficiency neutron multiplicity counter using 10B-coated thin tubes called straws. The detector was designed to perform like commercially available fission meters (manufactured by Ortec Corp.) except instead of using 3He gas as a neutron conversion material, we used a thin coating of 10B.

  12. REM Sleep Behavior Disorder and REM Sleep Without Atonia as an Early Manifestation of Degenerative Neurological Disease

    PubMed Central

    McCarter, Stuart J.; St Louis, Erik K.

    2013-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by repeated episodes of dream enactment behavior and REM sleep without atonia (RSWA) during polysomnography recording. RSWA is characterized by increased phasic or tonic muscle activity seen on polysomnographic electromyogram channels. RSWA is a requisite diagnostic feature of RBD, but may also be seen in patients without clinical symptoms or signs of dream enactment as an incidental finding in neurologically normal individuals, especially in patients receiving antidepressant therapy. RBD may be idiopathic or symptomatic. Patients with idiopathic RBD often later develop other neurological features including parkinsonism, orthostatic hypotension, anosmia, or cognitive impairment. RSWA without clinical symptoms as well as clinically overt RBD also often occurs concomitantly with the α-synucleinopathy family of neurodegenerative disorders, which includes idiopathic Parkinson disease, Lewy body dementia, and multiple system atrophy. This review article considers the epidemiology of RBD, clinical and polysomnographic diagnostic standards for both RBD and RSWA, previously reported associations of RSWA and RBD with neurodegenerative disorders and other potential causes, the pathophysiology of which brain structures and networks mediate dysregulation of REM sleep muscle atonia, and considerations for the effective and safe management of RBD. PMID:22328094

  13. REM sleep behavior disorder and REM sleep without atonia as an early manifestation of degenerative neurological disease.

    PubMed

    McCarter, Stuart J; St Louis, Erik K; Boeve, Bradley F

    2012-04-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by repeated episodes of dream enactment behavior and REM sleep without atonia (RSWA) during polysomnography recording. RSWA is characterized by increased phasic or tonic muscle activity seen on polysomnographic electromyogram channels. RSWA is a requisite diagnostic feature of RBD, but may also be seen in patients without clinical symptoms or signs of dream enactment as an incidental finding in neurologically normal individuals, especially in patients receiving antidepressant therapy. RBD may be idiopathic or symptomatic. Patients with idiopathic RBD often later develop other neurological features including parkinsonism, orthostatic hypotension, anosmia, or cognitive impairment. RSWA without clinical symptoms as well as clinically overt RBD also often occurs concomitantly with the α-synucleinopathy family of neurodegenerative disorders, which includes idiopathic Parkinson disease, Lewy body dementia, and multiple system atrophy. This review article considers the epidemiology of RBD, clinical and polysomnographic diagnostic standards for both RBD and RSWA, previously reported associations of RSWA and RBD with neurodegenerative disorders and other potential causes, the pathophysiology of which brain structures and networks mediate dysregulation of REM sleep muscle atonia, and considerations for the effective and safe management of RBD.

  14. Three Axis Acoustic Current Meter.

    DTIC Science & Technology

    1979-05-10

    MECHANICAL DESCRIPTION The ACM-i is housed in an aluminum case constructed of 6061-16 alloy (3000 ’meter working depth) or 7075-T6 alloy (6000 meter working...length 9.25 inches (23.5 cm) maximum diameter Materials: Al uminum housing (6061 alloy for 3000 meter option or 7075 alloy for 6000 meter option...housing through access hatch. 3. Purge unit with dry gas (dichiorodifluorome thane) by Injecting gas through hatch into copper tube running length of

  15. Impaired extinction of fear conditioning after REM deprivation is magnified by rearing in an enriched environment.

    PubMed

    Hunter, Amy Silvestri

    2015-07-01

    Evidence from both human and animal studies indicates that rapid eye movement sleep (REM) is essential for the acquisition and retention of information, particularly of an emotional nature. Learning and memory can also be impacted by manipulation of housing condition such as exposure to an enriched environment (EE). This study investigated the effects of REM deprivation and EE, both separately and combined, on the extinction of conditioned fear in rats. Consistent with prior studies, conditioning was enhanced in EE-reared rats and extinction was impaired in REM deprived rats. In addition, rats exposed to both REM deprivation and EE showed the greatest impairment in extinction, with effects persisting through the first two days of extinction training. This study is the first to explore the combination of REM deprivation and EE and suggests that manipulations that alter sleep, particularly REM, can have persisting deleterious effects on emotional memory processing.

  16. Dream recall after night awakenings from tonic/phasic REM sleep.

    PubMed

    Hodoba, Danilo; Hrabrić, Kremimir; Krmpotić, Pavao; Brecić, Petra; Kujundzić-Tiljak, Mirjana; Majdaneić, Zeljko

    2008-01-01

    Eleven healthy subjects, 9 females and 2 males aged 21-23, were submitted to all night polygraphic recording and awaken in REM (Rapid Eye Movements) sleep, randomly upon tonic or phasic REM. Immediately upon awakening subjects were asked about possible dreaming according to the standardized questionnaire. Seventy-seven dreams, i.e. 79% of all 97 REM awakenings, were reported and analyzed. There were no significant differences in reported frequency of dreamings after awakening, mood and dream content due to phasic/tonic REM sleep. Dreams from phasic REM were a bit more colorful. Predictor of morning remembering of dreams was meaninglessness, not meaningfulness of dreams, and, in lesser extent, good mood, colorfulness, dreams with words and phasic REM sleep.

  17. [Acoustic hallucinations as a symptom of a REM sleep-associated parasomnia].

    PubMed

    Sobanski, T; Sieb, J P; Laux, G; Möller, H J

    1997-11-01

    This 52-year-old man suffered from auditory hallucinations that occurred during brief episodes of sleep paralysis at the end of REM sleep periods. During these episodes the patient experienced a dissociated state of consciousness with REM sleep intrusions into wakefulness. The occurrence of this mixed state, and of excessive sleep-onset REM periods during daytime polysomnography (MSLT = Multiple Sleep Latency Test), point to a disorder of REM sleep generation. The existence of narcolepsy could be ruled out. The observation of REM sleep-associated hallucinations has been reported earlier. In the presented polysomnographic sleep studies the existence of a REM sleep associated parasomnia characterised by hallucinations and sleep paralysis could be confirmed.

  18. Rapid-REM: a MATLAB simulator of the replaced-elements model.

    PubMed

    Schultheis, Holger; Thorwart, Anna; Lachnit, Harald

    2008-05-01

    A recent proposal for an elemental account of associative learning phenomena is the replaced-elements model (REM) put forward by Wagner (2003). Although the ideas underlying this model are comparatively simple, implementation of the model is rather complex. In this article, we present Rapid-REM, a MATLAB simulator of Wagner's model. Rapid-REM features a graphical user interface for manipulating all essential parameter values and for control of the simulation process, graphical visualization of the simulation course and the results, and the alternative possibility of simulating the replaced-elements model as it was originally proposed (Wagner & Brandon, 2001). Rapid-REM is available free of charge from www.staff.uni-marburg.de/(tilde)lachnit/Rapid-REM/. This simulator makes it easy to derive predictions for REM and evaluate them, and it will therefore facilitate insights into the mechanisms of associative learning.

  19. Increased Motor Activity During REM Sleep Is Linked with Dopamine Function in Idiopathic REM Sleep Behavior Disorder and Parkinson Disease

    PubMed Central

    Zoetmulder, Marielle; Nikolic, Miki; Biernat, Heidi; Korbo, Lise; Friberg, Lars; Jennum, Poul

    2016-01-01

    Study Objectives: Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by impaired motor inhibition during REM sleep, and dream-enacting behavior. RBD is especially associated with α-synucleinopathies, such as Parkinson disease (PD). Follow-up studies have shown that patients with idiopathic RBD (iRBD) have an increased risk of developing an α-synucleinopathy in later life. Although abundant studies have shown that degeneration of the nigrostriatal dopaminergic system is associated with daytime motor function in Parkinson disease, only few studies have investigated the relation between this system and electromyographic (EMG) activity during sleep. The objective of this study was to investigate the relationship between the nigrostriatal dopamine system and muscle activity during sleep in iRBD and PD. Methods: 10 iRBD patients, 10 PD patients with PD, 10 PD patients without RBD, and 10 healthy controls were included and assessed with (123)I-N-omega-fluoropropyl-2-beta-carboxymethoxy-3beta-(4-iodophenyl) nortropane ((123)I-FP-CIT) Single-photon emission computed tomography (SPECT) scanning (123I-FP-CIT SPECT), neurological examination, and polysomnography. Results: iRBD patients and PD patients with RBD had increased EMG-activity compared to healthy controls. 123I-FP-CIT uptake in the putamen-region was highest in controls, followed by iRBD patients, and lowest in PD patients. In iRBD patients, EMG-activity in the mentalis muscle was correlated to 123I-FP-CIT uptake in the putamen. In PD patients, EMG-activity was correlated to anti-Parkinson medication. Conclusions: Our results support the hypothesis that increased EMG-activity during REM sleep is at least partly linked to the nigrostriatal dopamine system in iRBD, and with dopamine function in PD. Citation: Zoetmulder M, Nikolic M, Biernat H, Korbo L, Friberg L, Jennum P. Increased motor activity during rem sleep is linked with dopamine function in idiopathic REM sleep behavior

  20. Fuel meter for vehicles

    SciTech Connect

    Harde, B.

    1987-10-13

    A fuel level meter for vehicles is described including an electrical measuring device comprising: a voltage source and a potentiometer resistor. The resistor comprises two ends connected between the voltage source and a movable contact, connected to a float disposed in a fuel tank, such that the position of the float is dependent on the level of fuel in the tank; a shuntable series resistance with a first side connected to the movable contact and to a first relay switch of a relay and a second side connected both to a first resistor and to the relay switch. The other side of the first resistor is connected to a first side of a rheostat and to an overvoltage protector means; a damping capacitor having one side connected between the relay switch and a second relay switch of the relay operable jointly with the first. The measuring device is connected between a second side of the rheostat and ground; wherein the relay switches are jointly movable between a position wherein a first side of the capacitor and the second side of the shuntable series resistance are both electrically connected to an input terminal of the measuring device such that a current flowing from the movable contact flows through the series resistor and the other side of the capacitor is coupled to a constant voltage, and a second position wherein the series resistance is shunted off, the overvoltage protector means is engaged in parallel with the measuring device, and the capacitor maintains the constant voltage.

  1. Does Postural Rigidity Decrease during REM Sleep without Atonia in Parkinson Disease?

    PubMed Central

    Arnaldi, Dario; Latimier, Alice; Leu-Semenescu, Smaranda; De Carli, Fabrizio; Vidailhet, Marie; Arnulf, Isabelle

    2016-01-01

    Study Objectives: Rigidity is a muscle hypertonia typical of Parkinson disease (PD), whereas rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by abnormally increased muscle tone during REM sleep (REM sleep without atonia) and enacting dream behaviors. Because movements are not bradykinetic during RBD in patients with PD, we investigated whether the background, wake postural rigidity is attenuated during REM sleep without atonia, in absence of movement. Methods: The amplitude of levator menti (postural muscle) electromyographic activity during relaxed evening wakefulness (considered as reference) and sleep (N2, N3, atonic REM sleep, and quiet REM sleep without atonia) was measured in 20 patients with PD (with and without RBD), 10 patients with idiopathic RBD patients and 10 healthy subjects. Results: The chin tone amplitude progressively decreased from wake to N2, N3, and atonic REM sleep in the four groups, but the highest amplitude was observed in PD patients with RBD during atonic REM sleep. Furthermore, chin muscle tone amplitude did not attenuate from wake to REM sleep without atonia in patients with both PD and RBD but dramatically attenuated (by 40% on average) in patients with idiopathic RBD. Conclusions: The high amplitude of chin muscle tone in PD with RBD (but not in idiopathic RBD) during REM sleep with and without atonia suggests that both PD-related hypertonia and RBD-related enhanced muscle tone coexist during REM sleep, together affecting chin muscle tone. Consequently, some rapid RBD movements likely start against a rigid postural tone. Citation: Arnaldi D, Latimier A, Leu-Semenescu S, De Carli F, Vidailhet M, Arnulf I. Does postural rigidity decrease during REM sleep without atonia in Parkinson disease? J Clin Sleep Med 2016;12(6):839–847. PMID:26857056

  2. Localization of rem2 in the central nervous system of the adult rainbow trout (Oncorhynchus mykiss).

    PubMed

    Downs, Anna G; Scholles, Katie R; Hollis, David M

    2016-12-01

    Rem2 is member of the RGK (Rem, Rad, and Gem/Kir) subfamily of the Ras superfamily of GTP binding proteins known to influence Ca(2+) entry into the cell. In addition, Rem2, which is found at high levels in the vertebrate brain, is also implicated in cell proliferation and synapse formation. Though the specific, regional localization of Rem2 in the adult mammalian central nervous system has been well-described, such information is lacking in other vertebrates. Rem2 is involved in neuronal processes where the capacities between adults of different vertebrate classes vary. Thus, we sought to localize the rem2 gene in the central nervous system of an adult anamniotic vertebrate, the rainbow trout (Oncorhynchus mykiss). In situ hybridization using a digoxigenin (DIG)-labeled RNA probe was used to identify the regional distribution of rem2 expression throughout the trout central nervous system, while real-time polymerase chain reaction (rtPCR) further supported these findings. Based on in situ hybridization, the regional distribution of rem2 occurred within each major subdivision of the brain and included large populations of rem2 expressing cells in the dorsal telencephalon of the cerebrum, the internal cellular layer of the olfactory bulb, and the optic tectum of the midbrain. In contrast, no rem2 expressing cells were resolved within the cerebellum. These results were corroborated by rtPCR, where differential rem2 expression occurred between the major subdivisions assayed with the highest levels being found in the cerebrum, while it was nearly absent in the cerebellum. These data indicate that rem2 gene expression is broadly distributed and likely influences diverse functions in the adult fish central nervous system.

  3. Pharmacological REM sleep suppression paradoxically improves rather than impairs skill memory.

    PubMed

    Rasch, Björn; Pommer, Julian; Diekelmann, Susanne; Born, Jan

    2009-04-01

    Rapid eye movement (REM) sleep has been considered important for consolidation of memories, particularly of skills. Contrary to expectations, we found that REM sleep suppression by administration of selective serotonin or norepinephrine re-uptake inhibitors after training did not impair consolidation of skills or word-pairs in healthy men but rather enhanced gains in finger tapping accuracy together with sleep spindles. Our results indicate that REM sleep as a unitary phenomenon is not required for skill-memory consolidation.

  4. Effects of selective REM sleep deprivation on prefrontal gamma activity and executive functions.

    PubMed

    Corsi-Cabrera, M; Rosales-Lagarde, A; del Río-Portilla, Y; Sifuentes-Ortega, R; Alcántara-Quintero, B

    2015-05-01

    Given that the dorsolateral prefrontal cortex is involved in executive functions and is deactivated and decoupled from posterior associative regions during REM sleep, that Gamma temporal coupling involved in information processing is enhanced during REM sleep, and that adult humans spend about 90 min of every 24h in REM sleep, it might be expected that REM sleep deprivation would modify Gamma temporal coupling and have a deteriorating effect on executive functions. We analyzed EEG Gamma activity and temporal coupling during implementation of a rule-guided task before and after REM sleep deprivation and its effect on verbal fluency, flexible thinking and selective attention. After two nights in the laboratory for adaptation, on the third night subjects (n=18) were randomly assigned to either selective REM sleep deprivation effectuated by awakening them at each REM sleep onset or, the same number of NREM sleep awakenings as a control for unspecific effects of sleep interruptions. Implementation of abstract rules to guide behavior required greater activation and synchronization of Gamma activity in the frontopolar regions after REM sleep reduction from 20.6% at baseline to just 3.93% of total sleep time. However, contrary to our hypothesis, both groups showed an overall improvement in executive task performance and no effect on their capacity to sustain selective attention. These results suggest that after one night of selective REM sleep deprivation executive functions can be compensated by increasing frontal activation and they still require the participation of supervisory control by frontopolar regions.

  5. Electrophysiological Evidence for Alternative Motor Networks in REM Sleep Behavior Disorder.

    PubMed

    Hackius, Marc; Werth, Esther; Sürücü, Oguzkan; Baumann, Christian R; Imbach, Lukas L

    2016-11-16

    Patients with Parkinson's disease (PD) and REM sleep behavior disorder (RBD) show mostly unimpaired motor behavior during REM sleep, which contrasts strongly to coexistent nocturnal bradykinesia. The reason for this sudden amelioration of motor control in REM sleep is unknown, however. We set out to determine whether movements during REM sleep are processed by different motor networks than movements in the waking state. We recorded local field potentials in the subthalamic nucleus (STN) and scalp EEG (modified 10/20 montage) during sleep in humans with PD and RBD. Time-locked event-related β band oscillations were calculated during movements in REM sleep compared with movements in the waking state and during NREM sleep. Spectral analysis of STN local field potentials revealed elevated β power during REM sleep compared with NREM sleep and β power in REM sleep reached levels similar as in the waking state. Event-related analysis showed time-locked β desynchronization during WAKE movements. In contrast, we found significantly elevated β activity before and during movements in REM sleep and NREM sleep. Corticosubthalamic coherence was reduced during REM and NREM movements. We conclude that sleep-related movements are not processed by the same corticobasal ganglia network as movements in the waking state. Therefore, the well-known seemingly normal motor performance during RBD in PD patients might be generated by activating alternative motor networks for movement initiation. These findings support the hypothesis that pathological movement-inhibiting basal ganglia networks in PD patients are bypassed during sleep.

  6. Respiratory muscle activity during REM sleep in patients with diaphragm paralysis.

    PubMed

    Bennett, J R; Dunroy, H M A; Corfield, D R; Hart, N; Simonds, A K; Polkey, M I; Morrell, M J

    2004-01-13

    The diaphragm is the main inspiratory muscle during REM sleep. It was hypothesized that patients with isolated bilateral diaphragm paralysis (BDP) might not be able to sustain REM sleep. Polysomnography with EMG recordings was undertaken from accessory respiratory muscles in patients with BDP and normal subjects. Patients with BDP had a normal quantity of REM sleep (mean +/- SD, 18.6 +/- 7.5% of total sleep time) achieved by inspiratory recruitment of extradiaphragmatic muscles in both tonic and phasic REM, suggesting brainstem reorganization.

  7. Phasic Motor Activity of Respiratory and Non-Respiratory Muscles in REM Sleep

    PubMed Central

    Fraigne, Jimmy J.; Orem, John M.

    2011-01-01

    Objectives: In this study, we quantified the profiles of phasic activity in respiratory muscles (diaphragm, genioglossus and external intercostal) and non-respiratory muscles (neck and extensor digitorum) across REM sleep. We hypothesized that if there is a unique pontine structure that controls all REM sleep phasic events, the profiles of the phasic twitches of different muscle groups should be identical. Furthermore, we described how respiratory parameters (e.g., frequency, amplitude, and effort) vary across REM sleep to determine if phasic processes affect breathing. Methods: Electrodes were implanted in Wistar rats to record brain activity and muscle activity of neck, extensor digitorum, diaphragm, external intercostal, and genioglossal muscles. Ten rats were studied to obtain 313 REM periods over 73 recording days. Data were analyzed offline and REM sleep activity profiles were built for each muscle. In 6 animals, respiratory frequency, effort, amplitude, and inspiratory peak were also analyzed during 192 REM sleep periods. Results: Respiratory muscle phasic activity increased in the second part of the REM period. For example, genioglossal activity increased in the second part of the REM period by 63.8% compared to the average level during NREM sleep. This profile was consistent between animals and REM periods (η2 = 0.58). This increased activity seen in respiratory muscles appeared as irregular bursts and trains of activity that could affect rythmo-genesis. Indeed, the increased integrated activity seen in the second part of the REM period in the diaphragm was associated with an increase in the number (28.3%) and amplitude (30%) of breaths. Non-respiratory muscle phasic activity in REM sleep did not have a profile like the phasic activity of respiratory muscles. Time in REM sleep did not have an effect on nuchal activity (P = 0.59). Conclusion: We conclude that the concept of a common pontine center controlling all REM phasic events is not supported by our

  8. REM-sleep deprivation-induced increase in ethanol intake: role of brain monoaminergic neurons.

    PubMed

    Aalto, J; Kiianmaa, K

    1986-01-01

    The ethanol intake of Long-Evans male rats was recorded before, during and after deprivation of rapid eye movement (REM) sleep produced with the flowerpot technique modified by using a cuff pedestal and electrified grid floor instead of water. Ethanol intake increased significantly during REM-sleep deprivation. A rebound decrease in ethanol drinking was then observed during the REM-rebound phase immediately after the termination of REM-sleep deprivation. Because REM-sleep deprivation has been reported to impair the function of central monoamine neuronal systems and because some studies have implicated these systems in the control of voluntary ethanol intake, we studied whether different monoamine uptake blocking agents could antagonize the increase in ethanol intake caused by REM-sleep deprivation. After three days of REM-sleep deprivation, the rats were given uptake blocking agents for serotonin (citalopram, 5, 10 and 20 mg/kg/day, IP), dopamine (GBR 12909, 5 mg/kg/day, IP) and noradrenaline (talsupram, 1, 5 and 10 mg/kg/day, IP). Citalopram and GBR 12909 did not modify the increased level of ethanol intake, but talsupram decreased ethanol intake to the levels seen prior to deprivation, and during the REM-rebound phase amplified the decrease found. These effects of talsupram could be antagonized by blocking mg/kg/day, IP). Prazosin alone tended to increase ethanol consumption. These findings suggest that functional alterations in central noradrenergic neurons during REM-sleep deprivation may contribute to the concurrent increase in ethanol intake.

  9. The Metering Guide for Managers.

    ERIC Educational Resources Information Center

    Qayoumi, Mohammed H.

    This volume provides a guide to management of utilities metering in educational facilities, especially colleges and universities. Chapter 1 gives an overview of why utility measurement, specifically the metering of energy consumption, is important in facilities management. Chapter 2 defines the basic units of measurement for both electric and…

  10. Teaching Meter: Why and How.

    ERIC Educational Resources Information Center

    Roberts, John J.

    In poetry, the only escape from meter is mastery. An understanding of the physical basis of poetry contributes not only to the literary appreciation and analysis of poetry but also to effective communication and language usage in daily life. The ideal time to begin teaching meter is in early childhood, but many older students need to be…

  11. Wavelength meter having elliptical wedge

    DOEpatents

    Hackel, R.P.; Feldman, M.

    1992-12-01

    A wavelength meter is disclosed which can determine the wavelength of a laser beam from a laser source within an accuracy range of two parts in 10[sup 8]. The wavelength meter has wedge having an elliptically shaped face to the optical path of the laser source and includes interferometer plates which form a vacuum housing. 7 figs.

  12. Acoustic Ground-Impedance Meter

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.

    1983-01-01

    Helmoltz resonator used in compact, portable meter measures acoustic impedance of ground or other surfaces. Earth's surface is subject of increasing acoustical investigations because of its importance in aircraft noise prediction and measurment. Meter offers several advantages. Is compact and portable and set up at any test site, irrespective of landscape features, weather or other environmental condition.

  13. Wavelength meter having elliptical wedge

    DOEpatents

    Hackel, Richard P.; Feldman, Mark

    1992-01-01

    A wavelength meter is disclosed which can determine the wavelength of a laser beam from a laser source within an accuracy range of two parts in 10.sup.8. The wavelength meter has wedge having an elliptically shaped face to the optical path of the laser source and includes interferometer plates which form a vacuum housing.

  14. Overnight improvements in two REM sleep-sensitive tasks are associated with both REM and NREM sleep changes, sleep spindle features, and awakenings for dream recall.

    PubMed

    Nielsen, T; O'Reilly, C; Carr, M; Dumel, G; Godin, I; Solomonova, E; Lara-Carrasco, J; Blanchette-Carrière, C; Paquette, T

    2015-07-01

    Memory consolidation is associated with sleep physiology but the contribution of specific sleep stages remains controversial. To clarify the contribution of REM sleep, participants were administered two REM sleep-sensitive tasks to determine if associated changes occurred only in REM sleep. Twenty-two participants (7 men) were administered the Corsi Block Tapping and Tower of Hanoi tasks prior to and again after a night of sleep. Task improvers and non-improvers were compared for sleep structure, sleep spindles, and dream recall. Control participants (N = 15) completed the tasks twice during the day without intervening sleep. Overnight Corsi Block improvement was associated with more REM sleep whereas Tower of Hanoi improvement was associated with more N2 sleep. Corsi Block improvement correlated positively with %REM sleep and Tower of Hanoi improvement with %N2 sleep. Post-hoc analyses suggest Tower of Hanoi effects-but not Corsi Block effects-are due to trait differences. Sleep spindle density was associated with Tower of Hanoi improvement whereas spindle amplitude correlated with Corsi Block improvement. Number of REM awakenings for dream reporting (but not dream recall per se) was associated with Corsi Block, but not Tower of Hanoi, improvement but was confounded with REM sleep time. This non-replication of one of 2 REM-sensitive task effects challenges both 'dual-process' and 'sequential' or 'sleep organization' models of sleep-dependent learning and points rather to capacity limitations on REM sleep. Experimental awakenings for sampling dream mentation may not perturb sleep-dependent learning effects; they may even enhance them.

  15. Antidepressant suppression of non-REM sleep spindles and REM sleep impairs hippocampus-dependent learning while augmenting striatum-dependent learning.

    PubMed

    Watts, Alain; Gritton, Howard J; Sweigart, Jamie; Poe, Gina R

    2012-09-26

    Rapid eye movement (REM) sleep enhances hippocampus-dependent associative memory, but REM deprivation has little impact on striatum-dependent procedural learning. Antidepressant medications are known to inhibit REM sleep, but it is not well understood if antidepressant treatments impact learning and memory. We explored antidepressant REM suppression effects on learning by training animals daily on a spatial task under familiar and novel conditions, followed by training on a procedural memory task. Daily treatment with the antidepressant and norepinephrine reuptake inhibitor desipramine (DMI) strongly suppressed REM sleep in rats for several hours, as has been described in humans. We also found that DMI treatment reduced the spindle-rich transition-to-REM sleep state (TR), which has not been previously reported. DMI REM suppression gradually weakened performance on a once familiar hippocampus-dependent maze (reconsolidation error). DMI also impaired learning of the novel maze (consolidation error). Unexpectedly, learning of novel reward positions and memory of familiar positions were equally and oppositely correlated with amounts of TR sleep. Conversely, DMI treatment enhanced performance on a separate striatum-dependent, procedural T-maze task that was positively correlated with the amounts of slow-wave sleep (SWS). Our results suggest that learning strategy switches in patients taking REM sleep-suppressing antidepressants might serve to offset sleep-dependent hippocampal impairments to partially preserve performance. State-performance correlations support a model wherein reconsolidation of hippocampus-dependent familiar memories occurs during REM sleep, novel information is incorporated and consolidated during TR, and dorsal striatum-dependent procedural learning is augmented during SWS.

  16. Roadmap to risk evaluation and mitigation strategies (REMS) success

    PubMed Central

    Balian, John D.; Malhotra, Rachpal; Perentesis, Valerie

    2010-01-01

    Medical safety-related risk management is a rapidly evolving and increasingly important aspect of drug approval and market longevity. To effectively meet the challenges of this new era, we describe a risk management roadmap that proactively yet practically anticipates risk-management requirements, provides the foundation for enduring yet appropriately flexible risk-management practices, and leverages these techniques to efficiently and effectively utilize risk evaluation and mitigation strategies (REMS)/risk minimization programs as market access enablers. This fully integrated risk-management paradigm creates exciting opportunities for newer tools, techniques, and approaches to more successfully optimize product development, approval, and commercialization, with patients as the ultimate beneficiaries. PMID:25083193

  17. Neutron and gamma-ray shielding requirements for a below-ground neutrino detector system at the Rutherford Laboratory Spallation Neutron Source

    SciTech Connect

    Gabriel, T.A.; Lillie, R.A.; Childs, R.L.; Wilczynski, J.; Zeitnitz, B.

    1983-03-01

    The neutron and gamma-ray shielding requirements for a proposed neutrino system below the target station at the Rutherford Laboratory Spallation Neutron Source (SNS) are studied. The present shield below the station consists of 2 meters of iron and 1 meter of concrete, below which is chalk (CaCO/sub 3/). An underground bunker housing the neutrino detector system would require additional shielding consisting of 6 meters of the chalk plus approx. 3 meters of iron to reduce the number of high-energy (> approx. 7 MeV) neutrons and gamma rays entering the detector system to an acceptable level of approx. 1 per day.

  18. Parkinson's Disease and REM Sleep Behavior Disorder Result in Increased Non-Motor Symptoms

    PubMed Central

    Neikrug, Ariel B.; Avanzino, Julie A.; Liu, Lianqi; Maglione, Jeanne E.; Natarajan, Loki; Corey-Bloom, Jody; Palmer, Barton W.; Loredo, Jose S.; Ancoli-Israel, Sonia

    2014-01-01

    Objective Rapid Eye Movement (REM) sleep behavior disorder is often co-morbid with Parkinson's disease (PD). The current study aimed to provide a detailed understanding of the impact of having REM sleep behavior disorder on multiple NMS in patients with PD. Methods 86 participants were evaluated for REM-sleep behavior disorder and assessed for multiple non-motor symptoms of PD. Principal component analysis was utilized to model multiple measures of non-motor symptoms in PD and a multivariate analysis of variance was used to assess the relationship between REM-sleep behavior disorder and the multiple non-motor symptoms measures. Seven non-motor symptoms measures were assessed: cognition, quality of life, fatigue, sleepiness, overall sleep, mood, and overall non-motor symptoms of PD. Results 36 PD patients were classified as having REM-sleep behavior disorder (objective polysomnography and subjective findings), 26 as not having REM-sleep behavior disorder (neither objective nor subjective findings), and 24 as probable REM-sleep behavior disorder (either subjective or objective findings). REM-sleep behavior disorder was a significant predictor of increased non-motor symptoms in PD while controlling for dopaminergic therapy and age (p=0.01). The REM-sleep behavior disorder group reported more non-motor symptoms of depression (p=0.012), fatigue (p=0.036), overall sleep (p=0.018), and overall non-motor symptoms (p=0.002). Conclusion In PD, REM-sleep behavior disorder is associated with more non-motor symptoms, particularly increased depressive symptoms, sleep disturbances, and fatigue. More research is needed to assess whether PD patients with REM-sleep behavior disorder represent a subtype of PD with different disease progression and phenomenological presentation. PMID:24938585

  19. Dissociable learning-dependent changes in REM and non-REM sleep in declarative and procedural memory systems.

    PubMed

    Fogel, Stuart M; Smith, Carlyle T; Cote, Kimberly A

    2007-06-04

    Sleep spindles and rapid eye movements have been found to increase following an intense period of learning on a combination of procedural memory tasks. It is not clear whether these changes are task specific, or the result of learning in general. The current study investigated changes in spindles, rapid eye movements, K-complexes and EEG spectral power following learning in good sleepers randomly assigned to one of four learning conditions: Pursuit Rotor (n=9), Mirror Tracing (n=9), Paired Associates (n=9), and non-learning controls (n=9). Following Pursuit Rotor learning, there was an increase in the duration of Stage 2 sleep, spindle density (number of spindles/min), average spindle duration, and an increase in low frequency sigma power (12-14Hz) at occipital regions during SWS and at frontal regions during Stage 2 sleep in the second half of the night. These findings are consistent with previous findings that Pursuit Rotor learning is consolidated during Stage 2 sleep, and provide additional data to suggest that spindles across all non-REM stages may be a mechanism for brain plasticity. Following Paired Associates learning, theta power increased significantly at central regions during REM sleep. This study provides the first evidence that REM sleep theta activity is involved in declarative memory consolidation. Together, these findings support the hypothesis that brain plasticity during sleep does not involve a unitary process; that is, different types of learning have unique sleep-related memory consolidation mechanisms that act in dissociable brain regions at different times throughout the night.

  20. Antidepressants and REM sleep in Wistar-Kyoto and Sprague-Dawley rats.

    PubMed

    Ivarsson, Magnus; Paterson, Louise M; Hutson, Peter H

    2005-10-17

    Compared to other rat strains, the Wistar-Kyoto rats show increased amount of REM sleep, one of the characteristic sleep changes observed in depressed patients. The aims of this study were firstly to validate a simple sleep stage discriminator and then compare the effect of antidepressants on suppression of rapid eye movement (REM) sleep in Wistar-Kyoto rats and an outbred rat strain (Sprague-Dawley). Rats were implanted with telemetry transmitters with electroencephalogram/electromyogram electrodes. Following recovery, the animals were orally dosed at light onset with either desipramine (20 mg/kg), fluoxetine (10 mg/kg), citalopram (10 or 40 mg/kg) or vehicle in a cross-over design. Every 12-s epoch was automatically scored as WAKE, NREM or REM sleep. Results confirm that Wistar-Kyoto rats show increased amount of REM sleep and decreased REM latency compared with Sprague-Dawley rats. All antidepressants significantly suppressed REM sleep in Sprague-Dawley rats, but only the high dose of citalopram suppressed REM sleep in Wistar-Kyoto rats. These findings suggest that the enhanced REM activity in Wistar-Kyoto rats is less sensitive to the effect of antidepressants and therefore does not provide any additional predictive validity for assessing antidepressant efficacy.

  1. H-reflex suppression and autonomic activation during lucid REM sleep: a case study.

    PubMed

    Brylowski, A; Levitan, L; LaBerge, S

    1989-08-01

    A single subject, a proficient lucid dreamer experienced with signaling the onset of lucidity (reflective consciousness of dreaming) by means of voluntary eye movements, spent 4 nonconsecutive nights in the sleep laboratory. The subject reported becoming lucid and signaling in 8 of the 18 rapid-eye movement (REM) periods recorded. Ten lucid dream reports were verified by polygraphic examination of signals, providing a total of 12.5 min of signal-verified lucid REM. H-Reflex amplitude was recorded every 5 s, along with continuous recording of electroencephalogram, electrooculogram, electromyogram, electrocardiogram, finger pulse, and respiration. Significant findings included greater mean H-reflex suppression during lucid REM sleep than during nonlucid REM and correlations of H-reflex suppression with increased eye movement density, heart rate, and respiration rate. These results support previous studies reporting that lucid REM is not, as might be supposed, a state closer to awakening than ordinary, or nonlucid, REM; rather, lucid dreaming occurs during unequivocal REM sleep and is characteristically associated with phasic REM activation.

  2. The supramammillary nucleus and the claustrum activate the cortex during REM sleep

    PubMed Central

    Renouard, Leslie; Billwiller, Francesca; Ogawa, Keiko; Clément, Olivier; Camargo, Nutabi; Abdelkarim, Mouaadh; Gay, Nadine; Scoté-Blachon, Céline; Touré, Rouguy; Libourel, Paul-Antoine; Ravassard, Pascal; Salvert, Denise; Peyron, Christelle; Claustrat, Bruno; Léger, Lucienne; Salin, Paul; Malleret, Gael; Fort, Patrice; Luppi, Pierre-Hervé

    2015-01-01

    Evidence in humans suggests that limbic cortices are more active during rapid eye movement (REM or paradoxical) sleep than during waking, a phenomenon fitting with the presence of vivid dreaming during this state. In that context, it seemed essential to determine which populations of cortical neurons are activated during REM sleep. Our aim in the present study is to fill this gap by combining gene expression analysis, functional neuroanatomy, and neurochemical lesions in rats. We find in rats that, during REM sleep hypersomnia compared to control and REM sleep deprivation, the dentate gyrus, claustrum, cortical amygdaloid nucleus, and medial entorhinal and retrosplenial cortices are the only cortical structures containing neurons with an increased expression of Bdnf, FOS, and ARC, known markers of activation and/or synaptic plasticity. Further, the dentate gyrus is the only cortical structure containing more FOS-labeled neurons during REM sleep hypersomnia than during waking. Combining FOS staining, retrograde labeling, and neurochemical lesion, we then provide evidence that FOS overexpression occurring in the cortex during REM sleep hypersomnia is due to projections from the supramammillary nucleus and the claustrum. Our results strongly suggest that only a subset of cortical and hippocampal neurons are activated and display plasticity during REM sleep by means of ascending projections from the claustrum and the supramammillary nucleus. Our results pave the way for future studies to identify the function of REM sleep with regard to dreaming and emotional memory processing. PMID:26601158

  3. The One-Meter Dash

    ERIC Educational Resources Information Center

    Brooks, Mattie J.

    1977-01-01

    A game for two teams employs dice, meter sticks, and Cuisenaire rods. The game gives practice in number facts, regrouping, and use of rods; it can also serve as an introduction to the metric system. (SD)

  4. Angular velocity and acceleration meter

    NASA Technical Reports Server (NTRS)

    Melamed, L.

    1972-01-01

    Meter uses a liquid crystalline film which changes coloration due to shear-stresses produced by a rotating disk. Device is advantageous in that it is not subject to bearing failure or electrical burnouts as are conventional devices.

  5. Quantitative electroencephalography during rapid eye movement (REM) and non-REM sleep in combat-exposed veterans with and without post-traumatic stress disorder.

    PubMed

    Cohen, Daniel J; Begley, Amy; Alman, Jennie J; Cashmere, David J; Pietrone, Regina N; Seres, Robert J; Germain, Anne

    2013-02-01

    Sleep disturbances are a hallmark feature of post-traumatic stress disorder (PTSD), and associated with poor clinical outcomes. Few studies have examined sleep quantitative electroencephalography (qEEG), a technique able to detect subtle differences that polysomnography does not capture. We hypothesized that greater high-frequency qEEG would reflect 'hyperarousal' in combat veterans with PTSD (n = 16) compared to veterans without PTSD (n = 13). EEG power in traditional EEG frequency bands was computed for artifact-free sleep epochs across an entire night. Correlations were performed between qEEG and ratings of PTSD symptoms and combat exposure. The groups did not differ significantly in whole-night qEEG measures for either rapid eye movement (REM) or non-REM (NREM) sleep. Non-significant medium effect sizes suggest less REM beta (opposite to our hypothesis), less REM and NREM sigma and more NREM gamma in combat veterans with PTSD. Positive correlations were found between combat exposure and NREM beta (PTSD group only), and REM and NREM sigma (non-PTSD group only). Results did not support global hyperarousal in PTSD as indexed by increased beta qEEG activity. The correlation of sigma activity with combat exposure in those without PTSD and the non-significant trend towards less sigma activity during both REM and NREM sleep in combat veterans with PTSD suggests that differential information processing during sleep may characterize combat-exposed military veterans with and without PTSD.

  6. Gamma radiation field intensity meter

    DOEpatents

    Thacker, L.H.

    1994-08-16

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  7. Gamma radiation field intensity meter

    DOEpatents

    Thacker, Louis H.

    1995-01-01

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  8. Gamma radiation field intensity meter

    DOEpatents

    Thacker, Louis H.

    1994-01-01

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

  9. Healthcare Energy Metering Guidance (Brochure)

    SciTech Connect

    Not Available

    2011-07-01

    This brochure is intended to help facility and energy managers plan and prioritize investments in energy metering. It offers healthcare-specific examples of metering applications, benefits, and steps that other health systems can reproduce. It reflects collaborative input from the U.S. Department of Energy national laboratories and the health system members of the DOE Hospital Energy Alliance's Benchmarking and Measurement Project Team.

  10. Gamma radiation field intensity meter

    SciTech Connect

    Thacker, L.H.

    1995-10-17

    A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

  11. Semiempirical Investigation of the Indirect Exchange Interaction in a rem-IN System

    NASA Astrophysics Data System (ADS)

    Shakarov, Kh. O.

    2014-05-01

    The Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange interaction is investigated for the first time in compounds of binary REM (rare-earth metal) - In systems (REМ = Gd, Tb, Dy, Ho, Er, or Тm) using experimental values of the paramagnetic Curie temperature (θp ) of these compounds. The prediction of the RKKY theory on the direct proportionality between θp and the de Gennes factor for equiatomic compounds of heavy REM with indium, similarly to pure REM, is confirmed. Values of the indirect exchange interaction parameter are estimated semiempirically for the examined compounds. As a whole, it is established that for the compounds of REM with indium, as for pure REM, the exchange interaction of RKKY type is characteristic.

  12. The effect of a REM sleep deprivation procedure on different aspects of memory function in humans.

    PubMed

    Saxvig, Ingvild West; Lundervold, Astri Johansen; Grønli, Janne; Ursin, Reidun; Bjorvatn, Bjørn; Portas, Chiara Maria

    2008-03-01

    Previous studies have suggested that memory is dependent on the occurrence of REM sleep. Research has mainly focused on two distinct types of memory function, declarative and procedural, and it seems that the latter may more directly depend on REM sleep. Memory consolidation has been more investigated than acquisition, maintenance, and recall, despite the fact that sleep may affect flow of information into/from storage. Moreover, tests have often been limited to stimuli within only one modality (usually visual or verbal). This study aimed to clarify the role of REM sleep in memory by investigating aspects of memory function, processing, and modality in the same experimental setting. Tests of acquisition and consolidation of multiple aspects of memory function within the visual and verbal modalities were administrated to subjects before and after REM sleep deprivation. Results show that test performance was not affected by REM sleep deprivation.

  13. Emotional arousal modulates oscillatory correlates of targeted memory reactivation during NREM, but not REM sleep

    PubMed Central

    Lehmann, Mick; Schreiner, Thomas; Seifritz, Erich; Rasch, Björn

    2016-01-01

    Rapid eye movement (REM) sleep is considered to preferentially reprocess emotionally arousing memories. We tested this hypothesis by cueing emotional vs. neutral memories during REM and NREM sleep and wakefulness by presenting associated verbal memory cues after learning. Here we show that cueing during NREM sleep significantly improved memory for emotional pictures, while no cueing benefit was observed during REM sleep. On the oscillatory level, successful memory cueing during NREM sleep resulted in significant increases in theta and spindle oscillations with stronger responses for emotional than neutral memories. In contrast during REM sleep, solely cueing of neutral (but not emotional) memories was associated with increases in theta activity. Our results do not support a preferential role of REM sleep for emotional memories, but rather suggest that emotional arousal modulates memory replay and consolidation processes and their oscillatory correlates during NREM sleep. PMID:27982120

  14. Cortical activation patterns herald successful dream recall after NREM and REM sleep.

    PubMed

    Chellappa, Sarah Laxhmi; Frey, Sylvia; Knoblauch, Vera; Cajochen, Christian

    2011-05-01

    Dreaming pertains to both REM and NREM sleep. However, frequency and regional specific differences in EEG activity remains controversial. We investigated NREM and REM sleep EEG power density associated with and without dream recall in 17 young subjects during a 40-h multiple nap protocol under constant routine conditions. NREM sleep was associated with lower EEG power density for dream recall in the delta range, particularly in frontal derivations, and in the spindle range in centro-parietal derivations. REM sleep was associated with low frontal alpha activity and with high alpha and beta activity in occipital derivations. Our data indicate that specific EEG frequency- and topography changes underlie differences between dream recall and no recall after both NREM and REM sleep awakening. This dual NREM-REM sleep modulation holds strong implications for the mechanistic understanding of this complex ongoing cognitive process.

  15. Emotional arousal modulates oscillatory correlates of targeted memory reactivation during NREM, but not REM sleep.

    PubMed

    Lehmann, Mick; Schreiner, Thomas; Seifritz, Erich; Rasch, Björn

    2016-12-16

    Rapid eye movement (REM) sleep is considered to preferentially reprocess emotionally arousing memories. We tested this hypothesis by cueing emotional vs. neutral memories during REM and NREM sleep and wakefulness by presenting associated verbal memory cues after learning. Here we show that cueing during NREM sleep significantly improved memory for emotional pictures, while no cueing benefit was observed during REM sleep. On the oscillatory level, successful memory cueing during NREM sleep resulted in significant increases in theta and spindle oscillations with stronger responses for emotional than neutral memories. In contrast during REM sleep, solely cueing of neutral (but not emotional) memories was associated with increases in theta activity. Our results do not support a preferential role of REM sleep for emotional memories, but rather suggest that emotional arousal modulates memory replay and consolidation processes and their oscillatory correlates during NREM sleep.

  16. Visual hallucinations and pontine demyelination in a child: possible REM dissociation?

    PubMed

    Vita, Maria Gabriella; Batocchi, Anna Paola; Dittoni, Serena; Losurdo, Anna; Cianfoni, Alessandro; Stefanini, Maria Chiara; Vollono, Catello; Della Marca, Giacomo; Mariotti, Paolo

    2008-12-15

    An 11 year-old-boy acutely developed complex visual and acoustic hallucinations. Hallucinations, consisting of visions of a threatening, evil character of the Harry Potter saga, persisted for 3 days. Neurological and psychiatric examinations were normal. Ictal EEG was negative. MRI documented 3 small areas of hyperintense signal in the brainstem, along the paramedian and lateral portions of pontine tegmentum, one of which showed post-contrast enhancement. These lesions were likely of inflammatory origin, and treatment with immunoglobulins was started. Polysomnography was normal, multiple sleep latency test showed a mean sleep latency of 8 minutes, with one sleep-onset REM period. The pontine tegmentum is responsible for REM sleep regulation, and contains definite "REM-on" and "REM-off" regions. The anatomical distribution of the lesions permits us to hypothesize that hallucinations in this boy were consequent to a transient impairment of REM sleep inhibitory mechanisms, with the appearance of dream-like hallucinations during wake.

  17. Emergence of sensory patterns during sleep highlights differential dynamics of REM and non-REM sleep stages.

    PubMed

    Ramot, Michal; Fisch, Lior; Davidesco, Ido; Harel, Michal; Kipervasser, Svetlana; Andelman, Fani; Neufeld, Miri Y; Kramer, Uri; Fried, Itzhak; Malach, Rafael

    2013-09-11

    Despite the profound reduction in conscious awareness associated with sleep, sensory cortex remains highly active during the different sleep stages, exhibiting complex interactions between different cortical sites. The potential functional significance of such spatial patterns and how they change between different sleep stages is presently unknown. In this electrocorticography study of human patients, we examined this question by studying spatial patterns of activity (broadband gamma power) that emerge during sleep (sleep patterns) and comparing them to the functional organization of sensory cortex that is activated by naturalistic stimuli during the awake state. Our results show a high correlation (p < 10(-4), permutation test) between the sleep spatial patterns and the functional organization found during wakefulness. Examining how the sleep patterns changed through the night highlighted a stage-specific difference, whereby the repertoire of such patterns was significantly larger during rapid eye movement (REM) sleep compared with non-REM stages. These results reveal that intricate spatial patterns of sensory functional organization emerge in a stage-specific manner during sleep.

  18. Prediction analysis of dose equivalent responses of neutron dosemeters used at a MOX fuel facility.

    PubMed

    Tsujimura, N; Yoshida, T; Takada, C

    2011-07-01

    To predict how accurately neutron dosemeters can measure the neutron dose equivalent (rate) in MOX fuel fabrication facility work environments, the dose equivalent responses of neutron dosemeters were calculated by the spectral folding method. The dosemeters selected included two types of personal dosemeter, namely a thermoluminescent albedo neutron dosemeter and an electronic neutron dosemeter, three moderator-based neutron survey meters, and one special instrument called an H(p)(10) monitor. The calculations revealed the energy dependences of the responses expected within the entire range of neutron spectral variations observed in neutron fields at workplaces.

  19. Electronic Reliability and the Environmental Thermal Neutron Flux

    DTIC Science & Technology

    2007-11-02

    several Californium sources of varying strengths. The room is ten by ten by three meters. It is below ground with concrete walls. In a high flux...desirable for calibrating the system. Californium -252 is a self-fissioning fast neutron source, which can be moderated to produce thermal neutrons...NIST has several Californium sources with strengths as high as 200 mrem/h at one meter. The Cf sources are stored below the floor for the safety

  20. Insert metering plates for gas turbine nozzles

    DOEpatents

    Burdgick, Steven S.; Itzel, Gary; Chopra, Sanjay; Abuaf, Nesim; Correia, Victor H.

    2004-05-11

    The invention comprises a metering plate which is assembled to an impingement insert for use in the nozzle of a gas turbine. The metering plate can have one or more metering holes and is used to balance the cooling flow within the nozzle. A metering plate with multiple holes reduces static pressure variations which result from the cooling airflow through the metering plate. The metering plate can be assembled to the insert before or after the insert is inserted into the nozzle.

  1. Atmospheric neutrons

    NASA Technical Reports Server (NTRS)

    Korff, S. A.; Mendell, R. B.; Merker, M.; Light, E. S.; Verschell, H. J.; Sandie, W. S.

    1979-01-01

    Contributions to fast neutron measurements in the atmosphere are outlined. The results of a calculation to determine the production, distribution and final disappearance of atmospheric neutrons over the entire spectrum are presented. An attempt is made to answer questions that relate to processes such as neutron escape from the atmosphere and C-14 production. In addition, since variations of secondary neutrons can be related to variations in the primary radiation, comment on the modulation of both radiation components is made.

  2. Rare-earth metals (REMs) in nickel aluminide-based alloys: I. Physicochemical laws of interaction in the Ni-Al-REM and Ni x Al y -REM-AE (alloying element) systems

    NASA Astrophysics Data System (ADS)

    Povarova, K. B.; Kazanskaya, N. K.; Drozdov, A. A.; Morozov, A. E.

    2008-02-01

    The data on the Ni-Al- R ( R = REM Sc, Y, La, lanthanides) binary and ternary systems and the interactions of three rare-earth metals (yttrium, lanthanum, cerium) with the main alloying elements (Ti (Zr, Hf), Cr (Mo, W) that are introduced into Ni3Al-based VKNA alloys are analyzed. The binary aluminides of REMs in the Ni-Al- R ternary systems are shown to be in equilibrium with neither NiAl nor Ni3Al. The solid solution of aluminum in RNi5, which penetrates deep into these ternary systems, is the most stable phase in equilibrium with Ni3Al. In the NiAl (Ni3Al)-AE- R systems, REM precipitation (segregation) on various defects and interfaces in nickel aluminides is likely to be the most probable, and REMs are thought to interact with the most active impurities in real alloys (C, O, N), since REMs have a large atomic radius and, thus, are virtually undissolved in nickel, aluminum, and nickel aluminides.

  3. Neutron skyshine from intense 14-MeV neutron source facility

    SciTech Connect

    Nakamura, T.; Hayashi, K.; Takahashi, A.; Torii, A.; Uwamino, Y.; Veda, M.

    1985-07-01

    The dose distribution and the spectrum variation of neutrons due to the skyshine effect have been measured with the high-efficiency rem counter, the multisphere spectrometer, and the NE-213 scintillator in the environment surrounding an intense 14-MeV neutron source facility. The dose distribution and the energy spectra of neutrons around the facility used as a skyshine source have also been measured to enable the absolute evaluation of the skyshine effect. The skyshine effect was analyzed by two multigroup Monte Carlo codes, NIMSAC and MMCR-2, by two discrete ordinates S /sub n/ codes, ANISN and DOT3.5, and by the shield structure design code for skyshine, SKYSHINE-II. The calculated results show good agreement with the measured results in absolute values. These experimental results should be useful as benchmark data for shyshine analysis and for shielding design of fusion facilities.

  4. Orexin-1 receptor blockade dysregulates REM sleep in the presence of orexin-2 receptor antagonism

    PubMed Central

    Dugovic, Christine; Shelton, Jonathan E.; Yun, Sujin; Bonaventure, Pascal; Shireman, Brock T.; Lovenberg, Timothy W.

    2014-01-01

    In accordance with the prominent role of orexins in the maintenance of wakefulness via activation of orexin-1 (OX1R) and orexin-2 (OX2R) receptors, various dual OX1/2R antagonists have been shown to promote sleep in animals and humans. While selective blockade of OX2R seems to be sufficient to initiate and prolong sleep, the beneficial effect of additional inhibition of OX1R remains controversial. The relative contribution of OX1R and OX2R to the sleep effects induced by a dual OX1/2R antagonist was further investigated in the rat, and specifically on rapid eye movement (REM) sleep since a deficiency of the orexin system is associated with narcolepsy/cataplexy based on clinical and pre-clinical data. As expected, the dual OX1/2R antagonist SB-649868 was effective in promoting non-REM (NREM) and REM sleep following oral dosing (10 and 30 mg/kg) at the onset of the dark phase. However, a disruption of REM sleep was evidenced by a more pronounced reduction in the onset of REM as compared to NREM sleep, a marked enhancement of the REM/total sleep ratio, and the occurrence of a few episodes of direct wake to REM sleep transitions (REM intrusion). When administered subcutaneously, the OX2R antagonist JNJ-10397049 (10 mg/kg) increased NREM duration whereas the OX1R antagonist GSK-1059865 (10 mg/kg) did not alter sleep. REM sleep was not affected either by OX2R or OX1R blockade alone, but administration of the OX1R antagonist in combination with the OX2R antagonist induced a significant reduction in REM sleep latency and an increase in REM sleep duration at the expense of the time spent in NREM sleep. These results indicate that additional blockade of OX1R to OX2R antagonism elicits a dysregulation of REM sleep by shifting the balance in favor of REM sleep at the expense of NREM sleep that may increase the risk of adverse events. Translation of this hypothesis remains to be tested in the clinic. PMID:24592208

  5. Neutron dosimetry

    DOEpatents

    Quinby, Thomas C.

    1976-07-27

    A method of measuring neutron radiation within a nuclear reactor is provided. A sintered oxide wire is disposed within the reactor and exposed to neutron radiation. The induced radioactivity is measured to provide an indication of the neutron energy and flux within the reactor.

  6. Neutron guide

    DOEpatents

    Greene, Geoffrey L.

    1999-01-01

    A neutron guide in which lengths of cylindrical glass tubing have rectangular glass plates properly dimensioned to allow insertion into the cylindrical glass tubing so that a sealed geometrically precise polygonal cross-section is formed in the cylindrical glass tubing. The neutron guide provides easier alignment between adjacent sections than do the neutron guides of the prior art.

  7. REM: A Collaborative Framework for Building Indigenous Cultural Competence.

    PubMed

    Power, Tamara; Virdun, Claudia; Sherwood, Juanita; Parker, Nicola; Van Balen, Jane; Gray, Joanne; Jackson, Debra

    2016-09-01

    The well-documented health disparities between the Australian Indigenous and non-Indigenous population mandates a comprehensive response from health professionals. This article outlines the approach taken by one faculty of health in a large urban Australian university to enhance cultural competence in students from a variety of fields. Here we outline a collaborative and deeply respectful process of Indigenous and non-Indigenous university staff collectively developing a model that has framed the embedding of a common faculty Indigenous graduate attribute across the curriculum. Through collaborative committee processes, the development of the principles of "Respect; Engagement and sharing; Moving forward" (REM) has provided both a framework and way of "being and doing" our work. By drawing together the recurring principles and qualities that characterize Indigenous cultural competence the result will be students and staff learning and bringing into their lives and practice, important Indigenous cultural understanding.

  8. Hyperkalemic periodic paralysis associated with multiple sleep onset REM periods.

    PubMed

    Iranzo, A; Santamaria, J

    1999-12-15

    A 24-year-old man with sporadic hyperkalemic periodic paralysis (HPP) presented with moderate excessive daytime sleepiness and transitory episodes of weakness which occurred during and after sleep. Multiple sleep latency test (MSLT) demonstrated the presence of five sleep onset REM periods (SOREMPs) and a sleep latency of five minutes. Treatment with a diuretic which decreases serum potassium resolved all the clinical symtomps and a new MSLT showed the absence of SOREMPs and a sleep latency of 13.5 minutes. To our knowledge, the patient herein reported is the first case that associates sleep abnormalities and multiple SOREMPs with HPP. Furthermore, the present case suggests that SOREMPs may be explained by an increased extracellular potassium conductance related to HPP.

  9. Clinical implication of REM sleep behavior disorder in Parkinson's disease.

    PubMed

    Kim, Young Eun; Jeon, Beom S

    2014-01-01

    REM sleep behavior disorder (RBD) appears to have a predilection for some neurodegenerative disorders, especially synucleinopathies such as Parkinson's disease (PD), dementia with Lewy bodies and multiple system atrophy. The frequency of RBD in PD has been reported to variably range from 20 to 72%. RBD may precede or follow onset of parkinsonism. Idiopathic RBD may foreshadow neurodegenerative diseases, and RBD in patients with PD has several associated clinical factors although their causal or temporal relationships are not known. RBD may be associated with the development of hallucinations and dementia in PD. It has been reported that the male gender, old age, a non-tremor motor subtype, a more severe parkinsonism, fall, longer disease duration, autonomic dysfunction, and higher levodopa doses are factors associated with RBD in PD. This review will address the clinical implications of RBD as a preclinical marker of neurodegenerative diseases and PD phenotypes associated with RBD.

  10. Dream to Predict? REM Dreaming as Prospective Coding

    PubMed Central

    Llewellyn, Sue

    2016-01-01

    The dream as prediction seems inherently improbable. The bizarre occurrences in dreams never characterize everyday life. Dreams do not come true! But assuming that bizarreness negates expectations may rest on a misunderstanding of how the predictive brain works. In evolutionary terms, the ability to rapidly predict what sensory input implies—through expectations derived from discerning patterns in associated past experiences—would have enhanced fitness and survival. For example, food and water are essential for survival, associating past experiences (to identify location patterns) predicts where they can be found. Similarly, prediction may enable predator identification from what would have been only a fleeting and ambiguous stimulus—without prior expectations. To confront the many challenges associated with natural settings, visual perception is vital for humans (and most mammals) and often responses must be rapid. Predictive coding during wake may, therefore, be based on unconscious imagery so that visual perception is maintained and appropriate motor actions triggered quickly. Speed may also dictate the form of the imagery. Bizarreness, during REM dreaming, may result from a prospective code fusing phenomena with the same meaning—within a particular context. For example, if the context is possible predation, from the perspective of the prey two different predators can both mean the same (i.e., immediate danger) and require the same response (e.g., flight). Prospective coding may also prune redundancy from memories, to focus the image on the contextually-relevant elements only, thus, rendering the non-relevant phenomena indeterminate—another aspect of bizarreness. In sum, this paper offers an evolutionary take on REM dreaming as a form of prospective coding which identifies a probabilistic pattern in past events. This pattern is portrayed in an unconscious, associative, sensorimotor image which may support cognition in wake through being mobilized as a

  11. Sleepiness in Idiopathic REM Sleep Behavior Disorder and Parkinson Disease

    PubMed Central

    Arnulf, Isabelle; Neutel, Dulce; Herlin, Bastien; Golmard, Jean-Louis; Leu-Semenescu, Smaranda; Cochen de Cock, Valérie; Vidailhet, Marie

    2015-01-01

    Objective: To determine whether patients with idiopathic and symptomatic RBD were sleepier than controls, and if sleepiness in idiopathic RBD predicted earlier conversion to Parkinson disease. Methods: The Epworth Sleepiness Scale (ESS) and its determinants were compared at the time of a video-polysomnography for an RBD diagnosis in patients with idiopathic RBD, in patients with Parkinson disease, and in controls. Whether sleepiness at time of RBD diagnosis predicted an earlier conversion to neurodegenerative diseases was retrospectively analyzed in the followed-up patients. Results: The 75 patients with idiopathic RBD were sleepier (ESS: 7.8 ± 4.6) at the time of RBD diagnosis than 74 age- and sex-matched controls (ESS: 5.0 ± 3.6, P < 0.0001). They reached the levels of 114 patients with Parkinson disease (ESS: 8.7 ± 4.8), whether they had (n = 78) or did not have (n = 36) concomitant RBD. The severity of sleepiness in idiopathic RBD correlated with younger age, but not with sleep measures. Among the 69 patients with idiopathic RBD who were followed up for a median 3 years (1–15 years), 16 (23.2%) developed parkinsonism (n = 6), dementia (n = 6), dementia plus parkinsonism (n = 2), and multiple system atrophy (n = 2). An ESS greater than 8 at time of RBD diagnosis predicted a shorter time to phenoconversion to parkinsonism and dementia, from RBD onset, and from RBD diagnosis (when adjusted for age and time between RBD onset and diagnosis). Conclusions: Sleepiness is associated with idiopathic REM sleep behavior disorder and predicts more rapid conversion to parkinsonism and dementia, suggesting it is an early marker of neuronal loss in brainstem arousal systems. Citation: Arnulf I, Neutel D, Herlin B, Golmard JL, Leu-Semenescu S, Cochen de Cock V, Vidailhet M. Sleepiness in idiopathic REM sleep behavior disorder and Parkinson disease. SLEEP 2015;38(10):1529–1535. PMID:26085299

  12. 5-HT1A receptor-responsive pedunculopontine tegmental neurons suppress REM sleep and respiratory motor activity.

    PubMed

    Grace, Kevin P; Liu, Hattie; Horner, Richard L

    2012-02-01

    Serotonin type 1A (5-HT(1A)) receptor-responsive neurons in the pedunculopontine tegmental nucleus (PPTn) become maximally active immediately before and during rapid eye movement (REM) sleep. A prevailing model of REM sleep generation indicates that activation of such neurons contributes significantly to the generation of REM sleep, and if correct then inactivation of such neurons ought to suppress REM sleep. We test this hypothesis using bilateral microperfusion of the 5-HT(1A) receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT, 10 μm) into the PPTn; this tool has been shown to selectively silence REM sleep-active PPTn neurons while the activity of wake/REM sleep-active PPTn neurons is unaffected. Contrary to the prevailing model, bilateral microperfusion of 8-OH-DPAT into the PPTn (n = 23 rats) significantly increased REM sleep both as a percentage of the total recording time and sleep time, compared with both within-animal vehicle controls and between-animal time-controls. This increased REM sleep resulted from an increased frequency of REM sleep bouts but not their duration, indicating an effect on mechanisms of REM sleep initiation but not maintenance. Furthermore, an increased proportion of the REM sleep bouts stemmed from periods of low REM sleep drive quantified electrographically. Targeted suppression of 5-HT(1A) receptor-responsive PPTn neurons also increased respiratory rate and respiratory-related genioglossus activity, and increased the frequency and amplitude of the sporadic genioglossus activations occurring during REM sleep. These data indicate that 5-HT(1A) receptor-responsive PPTn neurons normally function to restrain REM sleep by elevating the drive threshold for REM sleep induction, and restrain the expression of respiratory rate and motor activities.

  13. Neutron multiplicity measurements with 3He alternative: Straw neutron detectors

    SciTech Connect

    Mukhopadhyay, Sanjoy; Wolff, Ronald; Detwiler, Ryan; Maurer, Richard; Mitchell, Stephen; Guss, Paul; Lacy, Jeffrey L.; Sun, Liang; Athanasiades, Athanasios

    2015-01-27

    Counting neutrons emitted by special nuclear material (SNM) and differentiating them from the background neutrons of various origins is the most effective passive means of detecting SNM. Unfortunately, neutron detection, counting, and partitioning in a maritime environment are complex due to the presence of high-multiplicity spallation neutrons (commonly known as ‘‘ship effect ’’) and to the complicated nature of the neutron scattering in that environment. A prototype neutron detector was built using 10B as the converter in a special form factor called ‘‘straws’’ that would address the above problems by looking into the details of multiplicity distributions of neutrons originating from a fissioning source. This paper describes the straw neutron multiplicity counter (NMC) and assesses the performance with those of a commercially available fission meter. The prototype straw neutron detector provides a large-area, efficient, lightweight, more granular (than fission meter) neutron-responsive detection surface (to facilitate imaging) to enhance the ease of application of fission meters. Presented here are the results of preliminary investigations, modeling, and engineering considerations leading to the construction of this prototype. This design is capable of multiplicity and Feynman variance measurements. This prototype may lead to a near-term solution to the crisis that has arisen from the global scarcity of 3He by offering a viable alternative to fission meters. This paper describes the work performed during a 2-year site-directed research and development (SDRD) project that incorporated straw detectors for neutron multiplicity counting. The NMC is a two-panel detector system. We used 10B (in the form of enriched boron carbide: 10B4C) for neutron detection instead of 3He. In the first year, the project worked with a panel of straw neutron detectors, investigated its characteristics, and

  14. Neutron multiplicity ,easurements With 3He alternative: Straw neutron detectors

    SciTech Connect

    Mukhopadhyay, Sanjoy; Wolff, Ronald S.; Meade, John A.; Detweiler, Ryan; Maurer, Richard J.; Mitchell, Stephen E.; Guss, Paul P.; Lacy, Jeffrey L.; Sun, Liang; Athanasiades, Athanasios

    2015-01-27

    Counting neutrons emitted by special nuclear material (SNM) and differentiating them from the background neutrons of various origins is the most effective passive means of detecting SNM. Unfortunately, neutron detection, counting, and partitioning in a maritime environment are complex due to the presence of high-multiplicity spallation neutrons (commonly known as “ship effect”) and to the complicated nature of the neutron scattering in that environment. In this study, a prototype neutron detector was built using 10B as the converter in a special form factor called “straws” that would address the above problems by looking into the details of multiplicity distributions of neutrons originating from a fissioning source. This paper describes the straw neutron multiplicity counter (NMC) and assesses the performance with those of a commercially available fission meter. The prototype straw neutron detector provides a large-area, efficient, lightweight, more granular (than fission meter) neutron-responsive detection surface (to facilitate imaging) to enhance the ease of application of fission meters. Presented here are the results of preliminary investigations, modeling, and engineering considerations leading to the construction of this prototype. This design is capable of multiplicity and Feynman variance measurements. This prototype may lead to a near-term solution to the crisis that has arisen from the global scarcity of 3He by offering a viable alternative to fission meters. This paper describes the work performed during a 2-year site-directed research and development (SDRD) project that incorporated straw detectors for neutron multiplicity counting. The NMC is a two-panel detector system. We used 10B (in the form of enriched boron carbide: 10B4C) for neutron detection instead of 3He. In the first year, the project worked with a panel of straw neutron detectors, investigated its characteristics

  15. REM Sleep-Dependent Bidirectional Regulation of Hippocampal-Based Emotional Memory and LTP.

    PubMed

    Ravassard, Pascal; Hamieh, Al Mahdy; Joseph, Mickaël Antoine; Fraize, Nicolas; Libourel, Paul-Antoine; Lebarillier, Léa; Arthaud, Sébastien; Meissirel, Claire; Touret, Monique; Malleret, Gaël; Salin, Paul-Antoine

    2016-04-01

    Prolonged rapid-eye-movement (REM) sleep deprivation has long been used to study the role of REM sleep in learning and memory processes. However, this method potentially induces stress and fatigue that may directly affect cognitive functions. Here, by using a short-term and nonstressful REM sleep deprivation (RSD) method we assessed in rats the bidirectional influence of reduced and increased REM sleep amount on hippocampal-dependent emotional memory and plasticity. Our results indicate that 4 h RSD impaired consolidation of contextual fear conditioning (CFC) and induction of long-term potentiation (LTP), while decreasing density of Egr1/Zif268-expressing neurons in the CA1 region of the dorsal hippocampus. LTP and Egr1 expression were not affected in ventral CA1. Conversely, an increase in REM sleep restores and further facilitates CFC consolidation and LTP induction, and also increases Egr1 expression in dorsal CA1. Moreover, CFC consolidation, Egr1 neuron density, and LTP amplitude in dorsal CA1 show a positive correlation with REM sleep amount. Altogether, these results indicate that mild changes in REM sleep amount bidirectionally affect memory and synaptic plasticity mechanisms occurring in the CA1 area of the dorsal hippocampus.

  16. Analysis of automated quantification of motor activity in REM sleep behaviour disorder.

    PubMed

    Frandsen, Rune; Nikolic, Miki; Zoetmulder, Marielle; Kempfner, Lykke; Jennum, Poul

    2015-10-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by dream enactment and REM sleep without atonia. Atonia is evaluated on the basis of visual criteria, but there is a need for more objective, quantitative measurements. We aimed to define and optimize a method for establishing baseline and all other parameters in automatic quantifying submental motor activity during REM sleep. We analysed the electromyographic activity of the submental muscle in polysomnographs of 29 patients with idiopathic RBD (iRBD), 29 controls and 43 Parkinson's (PD) patients. Six adjustable parameters for motor activity were defined. Motor activity was detected and quantified automatically. The optimal parameters for separating RBD patients from controls were investigated by identifying the greatest area under the receiver operating curve from a total of 648 possible combinations. The optimal parameters were validated on PD patients. Automatic baseline estimation improved characterization of atonia during REM sleep, as it eliminates inter/intra-observer variability and can be standardized across diagnostic centres. We found an optimized method for quantifying motor activity during REM sleep. The method was stable and can be used to differentiate RBD from controls and to quantify motor activity during REM sleep in patients with neurodegeneration. No control had more than 30% of REM sleep with increased motor activity; patients with known RBD had as low activity as 4.5%. We developed and applied a sensitive, quantitative, automatic algorithm to evaluate loss of atonia in RBD patients.

  17. Heart rate variability during carbachol-induced REM sleep and cataplexy.

    PubMed

    Torterolo, Pablo; Castro-Zaballa, Santiago; Cavelli, Matías; Velasquez, Noelia; Brando, Victoria; Falconi, Atilio; Chase, Michael H; Migliaro, Eduardo R

    2015-09-15

    The nucleus pontis oralis (NPO) exerts an executive control over REM sleep. Cholinergic input to the NPO is critical for REM sleep generation. In the cat, a single microinjection of carbachol (a cholinergic agonist) into the NPO produces either REM sleep (REMc) or wakefulness with muscle atonia (cataplexy, CA). In order to study the central control of the heart rate variability (HRV) during sleep, we conducted polysomnographic and electrocardiogram recordings from chronically prepared cats during REMc, CA as well as during sleep and wakefulness. Subsequently, we performed statistical and spectral analyses of the HRV. The heart rate was greater during CA compared to REMc, NREM or REM sleep. Spectral analysis revealed that the low frequency band (LF) power was significantly higher during REM sleep in comparison to REMc and CA. Furthermore, we found that during CA there was a decrease in coupling between the RR intervals plot (tachogram) and respiratory activity. In contrast, compared to natural behavioral states, during REMc and CA there were no significant differences in the HRV based upon the standard deviation of normal RR intervals (SDNN) and the mean squared difference of successive intervals (rMSSD). In conclusion, there were differences in the HRV during naturally-occurring REM sleep compared to REMc. In addition, in spite of the same muscle atonia, the HRV was different during REMc and CA. Therefore, the neuronal network that controls the HRV during REM sleep can be dissociated from the one that generates the muscle atonia during this state.

  18. REM/ROSS: a powerful tool for monitoring the prompt afterglow of γ-ray bursts

    NASA Astrophysics Data System (ADS)

    Tagliaferri, G.; Zerbi, F. M.; Chincarini, G.; Ghisellini, G.; Rodonò, M.; Palazzi, E.; Antonelli, L. A.; Conconi, P.; Covino, S.; Cutispoto, G.; Molinari, E.; Nicastro, L.; Tosti, G.; REM/ROSS Team

    2004-01-01

    Observations of the prompt afterglow of γ-ray burst events are unanimously considered of paramount importance for GRB science and cosmology. Such observations at NIR wavelengths are even more promising allowing the monitoring of high- z Ly-α absorbed bursts as well as events occurring in dusty star-forming regions. In these pages we present rapid eye mount (REM), a fully robotized fast slewing telescope equipped with a high throughput NIR (Z, J, H, K) camera dedicated to detecting the prompt IR afterglow. REM can discover objects at extremely high redshift and trigger large telescopes to observe them. The REM telescope will simultaneously feed REM optical slitless spectrograph (ROSS) via a dichroic. ROSS will intensively monitor the prompt optical continuum of GRB afterglows. The synergy between the REM-IR camera and the ROSS spectrograph makes REM a powerful observing tool for any kind of fast transient phenomena. Beside its ambitious scientific goals, REM is also technically challenging since it represent the first attempt to locate a NIR camera on a small telescope providing, with ROSS, unprecedented simultaneous wavelength coverage on a telescope of this size.

  19. Increased REM density in narcolepsy-cataplexy and the polysymptomatic form of idiopathic hypersomnia.

    PubMed

    Vanková, J; Nevsímalová, S; Sonka, K; Spacková, N; Svejdová-Blazejová, K

    2001-09-15

    The present work is focused on REM sleep density in patients with primary hypersomnia in comparison with non-hypersomnia subjects. 28 unmedicated patients with narcolepsy-cataplexy (NC) and 10 unmedicated patients suffering from the polysymptomatic form of idiopathic hypersomnia (IH) and their age- and sex-matched controls were included in the study. The clinical diagnosis was confirmed by MSLT and nocturnal PSG, HLA typing was performed in a respective group of narcoleptic patients. Polygraphical recordings were visually scored with particular regard to the two most characteristic phasic features of REM sleep: the number of rapid eye movements (REMs) and chin muscle twitches (Tws) per minute. These events were evaluated according to recognized criteria; a closer look was taken at both their frequency and their distribution across all the nocturnal REM periods (REMPs). The following main differences between hypersomniac patients (of both groups examined) and healthy controls were found in terms of phasic activity: (I) REM density (expressed in REMs/min and Tws/min in each REM period) was significantly increased in the hypersomniac patients in comparison with the controls. (p>0.05).(II) The intra-night phasic activity distribution was found rising more conspicuously in the hypersomniacs than in the controls.

  20. The effect of REM sleep deprivation on motivation for food reward.

    PubMed

    Hanlon, Erin C; Andrzejewski, Matthew E; Harder, Bridgette K; Kelley, Ann E; Benca, Ruth M

    2005-08-30

    Prolonged sleep deprivation in rats produces a characteristic syndrome consisting of an increase in food intake yet a decrease in weight. Moreover, the increase in food intake generally precedes the weight loss, suggesting that sleep deprivation may affect appetitive behaviors. Using the multiple platform method to produce rapid eye movement (REM) sleep deprivation, we investigated the effect of REM sleep deprivation (REMSD) on motivation for food reward utilizing food-reinforced operant tasks. In acquisition or maintenance of an operant task, REM sleep-deprived rats, with or without simultaneous food restriction, decreased responding for sucrose pellet reward in comparison to controls, despite the fact that all REM sleep-deprived rats lost weight. Furthermore, the overall response deficit of the REM sleep-deprived rats was due to a within-session decline in responding. REM sleep-deprived rats showed evidence of understanding the contingency of the task comparable to controls throughout deprivation period, suggesting that the decrements in responding were not primarily related to deficits in learning or memory. Rather, REM sleep deprivation appears to alter systems involved in motivational processes, reward, and/or attention.

  1. LINEAR COUNT-RATE METER

    DOEpatents

    Henry, J.J.

    1961-09-01

    A linear count-rate meter is designed to provide a highly linear output while receiving counting rates from one cycle per second to 100,000 cycles per second. Input pulses enter a linear discriminator and then are fed to a trigger circuit which produces positive pulses of uniform width and amplitude. The trigger circuit is connected to a one-shot multivibrator. The multivibrator output pulses have a selected width. Feedback means are provided for preventing transistor saturation in the multivibrator which improves the rise and decay times of the output pulses. The multivibrator is connected to a diode-switched, constant current metering circuit. A selected constant current is switched to an averaging circuit for each pulse received, and for a time determined by the received pulse width. The average output meter current is proportional to the product of the counting rate, the constant current, and the multivibrator output pulse width.

  2. Arduino based radiation survey meter

    NASA Astrophysics Data System (ADS)

    Rahman, Nur Aira Abd; Lombigit, Lojius; Abdullah, Nor Arymaswati; Azman, Azraf; Dolah, Taufik; Muzakkir, Amir; Jaafar, Zainudin; Mohamad, Glam Hadzir Patai; Ramli, Abd Aziz Mhd; Zain, Rasif Mohd; Said, Fazila; Khalid, Mohd Ashhar; Taat, Muhamad Zahidee

    2016-01-01

    This paper presents the design of new digital radiation survey meter with LND7121 Geiger Muller tube detector and Atmega328P microcontroller. Development of the survey meter prototype is carried out on Arduino Uno platform. 16-bit Timer1 on the microcontroller is utilized as external pulse counter to produce count per second or CPS measurement. Conversion from CPS to dose rate technique is also performed by Arduino to display results in micro Sievert per hour (μSvhr-1). Conversion factor (CF) value for conversion of CPM to μSvhr-1 determined from manufacturer data sheet is compared with CF obtained from calibration procedure. The survey meter measurement results are found to be linear for dose rates below 3500 µSv/hr.

  3. Arduino based radiation survey meter

    SciTech Connect

    Rahman, Nur Aira Abd Lombigit, Lojius; Abdullah, Nor Arymaswati; Azman, Azraf; Dolah, Taufik; Jaafar, Zainudin; Mohamad, Glam Hadzir Patai; Ramli, Abd Aziz Mhd; Zain, Rasif Mohd; Said, Fazila; Khalid, Mohd Ashhar; Taat, Muhamad Zahidee; Muzakkir, Amir

    2016-01-22

    This paper presents the design of new digital radiation survey meter with LND7121 Geiger Muller tube detector and Atmega328P microcontroller. Development of the survey meter prototype is carried out on Arduino Uno platform. 16-bit Timer1 on the microcontroller is utilized as external pulse counter to produce count per second or CPS measurement. Conversion from CPS to dose rate technique is also performed by Arduino to display results in micro Sievert per hour (μSvhr{sup −1}). Conversion factor (CF) value for conversion of CPM to μSvhr{sup −1} determined from manufacturer data sheet is compared with CF obtained from calibration procedure. The survey meter measurement results are found to be linear for dose rates below 3500 µSv/hr.

  4. REM Sleep and Its Loss-associated Epigenetic Regulation with Reference to Noradrenaline in Particular

    PubMed Central

    Mehta, Rachna; Singh, Abhishek; Bókkon, István; Nath Mallick, Birendra

    2016-01-01

    Sleep is an essential physiological process, which has been divided into rapid eye movement sleep (REMS) and non-REMS (NREMS) in higher animals. REMS is a unique phenomenon that unlike other sleep-waking states is not under voluntary control. Directly or indirectly it influences or gets influenced by most of the physiological processes controlled by the brain. It has been proposed that REMS serves housekeeping function of the brain. Extensive research has shown that during REMS at least noradrenaline (NA) -ergic neurons must cease activity and upon REMS loss, there are increased levels of NA in the brain, which then induces many of the REMS loss associated acute and chronic effects. The NA level is controlled by many bio-molecules that are regulated at the molecular and transcriptional levels. Similarly, NA can also directly or indirectly modulate the synthesis and levels of many molecules, which in turn may affect physiological processes. The burgeoning field of behavioral neuroepigenetics has gained importance in recent years and explains the regulatory mechanisms underlying several behavioral phenomena. As REMS and its loss associated changes in NA modulate several pathophysiological processes, in this review we have attempted to explain on one hand how the epigenetic mechanisms regulating the gene expression of factors like tyrosine hydroxylase (TH), monoamine oxidase (MAO), noradrenaline transporter (NAT) control NA levels and on the other hand, how NA per se can affect other molecules in neural circuitry at the epigenetic level resulting in behavioral changes in health and diseases. An understanding of these events will expose the molecular basis of REMS and its loss-associated pathophysiological changes; which are presented as a testable hypothesis for confirmation. PMID:26813120

  5. Enhanced emotional reactivity after selective REM sleep deprivation in humans: an fMRI study

    PubMed Central

    Rosales-Lagarde, Alejandra; Armony, Jorge L.; del Río-Portilla, Yolanda; Trejo-Martínez, David; Conde, Ruben; Corsi-Cabrera, Maria

    2012-01-01

    Converging evidence from animal and human studies suggest that rapid eye movement (REM) sleep modulates emotional processing. The aim of the present study was to explore the effects of selective REM sleep deprivation (REM-D) on emotional responses to threatening visual stimuli and their brain correlates using functional magnetic resonance imaging (fMRI). Twenty healthy subjects were randomly assigned to two groups: selective REM-D, by awakening them at each REM sleep onset, or non-rapid eye movement sleep interruptions (NREM-I) as control for potential non-specific effects of awakenings and lack of sleep. In a within-subject design, a visual emotional reactivity task was performed in the scanner before and 24 h after sleep manipulation. Behaviorally, emotional reactivity was enhanced relative to baseline (BL) in the REM deprived group only. In terms of fMRI signal, there was, as expected, an overall decrease in activity in the NREM-I group when subjects performed the task the second time, particularly in regions involved in emotional processing, such as occipital and temporal areas, as well as in the ventrolateral prefrontal cortex, involved in top-down emotion regulation. In contrast, activity in these areas remained the same level or even increased in the REM-D group, compared to their BL level. Taken together, these results suggest that lack of REM sleep in humans is associated with enhanced emotional reactivity, both at behavioral and neural levels, and thus highlight the specific role of REM sleep in regulating the neural substrates for emotional responsiveness. PMID:22719723

  6. Enhanced emotional reactivity after selective REM sleep deprivation in humans: an fMRI study.

    PubMed

    Rosales-Lagarde, Alejandra; Armony, Jorge L; Del Río-Portilla, Yolanda; Trejo-Martínez, David; Conde, Ruben; Corsi-Cabrera, Maria

    2012-01-01

    Converging evidence from animal and human studies suggest that rapid eye movement (REM) sleep modulates emotional processing. The aim of the present study was to explore the effects of selective REM sleep deprivation (REM-D) on emotional responses to threatening visual stimuli and their brain correlates using functional magnetic resonance imaging (fMRI). Twenty healthy subjects were randomly assigned to two groups: selective REM-D, by awakening them at each REM sleep onset, or non-rapid eye movement sleep interruptions (NREM-I) as control for potential non-specific effects of awakenings and lack of sleep. In a within-subject design, a visual emotional reactivity task was performed in the scanner before and 24 h after sleep manipulation. Behaviorally, emotional reactivity was enhanced relative to baseline (BL) in the REM deprived group only. In terms of fMRI signal, there was, as expected, an overall decrease in activity in the NREM-I group when subjects performed the task the second time, particularly in regions involved in emotional processing, such as occipital and temporal areas, as well as in the ventrolateral prefrontal cortex, involved in top-down emotion regulation. In contrast, activity in these areas remained the same level or even increased in the REM-D group, compared to their BL level. Taken together, these results suggest that lack of REM sleep in humans is associated with enhanced emotional reactivity, both at behavioral and neural levels, and thus highlight the specific role of REM sleep in regulating the neural substrates for emotional responsiveness.

  7. Eye Movements and Abducens Motoneuron Behavior During Cholinergically Induced REM Sleep

    PubMed Central

    Marquez-Ruiz, Javier; Escudero, Miguel

    2009-01-01

    Study objectives: The injection of cholinergic drugs in the pons has been largely used to induce REM sleep as a useful model to study different processes during this period. In the present study, microinjections of carbachol in the nucleus reticularis pontis oralis (NRPO) were performed to test the hypothesis that eye movements and the behavior of extraocular motoneurons during induced REM sleep do not differ from those during spontaneous REM sleep. Methods: Six female adult cats were prepared for chronic recording of eye movements (by means of the search-coil technique) and electroencephalography, electromyography, ponto-geniculo-occipital (PGO) waves at the lateral geniculate nucleus, and identified abducens motoneuron activities after microinjections of the cholinergic agonist carbachol into the NRPO. Results: Unilateral microinjections (n = 13) of carbachol in the NRPO induced REM sleep-like periods in which the eyes performed a convergence and downward rotation interrupted by phasic complex rapid eye movements associated to PGO waves. During induced-REM sleep abducens motoneurons lost their tonic activity and eye position codification, but continued codifying eye velocity during the burst of eye movements. Conclusion: The present results show that eye movements and the underlying behavior of abducens motoneurons are very similar to those present during natural REM sleep. Thus, microinjection of carbachol seems to activate the structures responsible for the exclusive oculomotor behavior observed during REM sleep, validating this pharmacological model and enabling a more efficient exploration of phasic and tonic phenomena underlying eye movements during REM sleep. Citation: Marquez-Ruiz J; Escudero M. Eye movements and abducens motoneuron behavior during cholinergically induced REM sleep. SLEEP 2009;32(4):471–481. PMID:19413141

  8. The effects of gender and age on REM-related sleep-disordered breathing.

    PubMed

    Koo, Brian B; Dostal, Jesse; Ioachimescu, Octavian; Budur, Kumaraswamy

    2008-08-01

    Sleep disordered breathing occurring predominantly in rapid eye movement REM sleep (rapid-eye-movement-related sleep-disordered breathing, REM SDB) is present in 10 to 36% of patients undergoing polysomnography (PSG) for suspected obstructive sleep apnea (O'Connor et al. in Am J Respir Crit Care Med 161:1465-1472, 2000; Resta et al. in J Respir Medicine 99:91-96, 2005; Haba-Rubio et al. in Chest 128:3350-3357, 2005; Juvelekian and Golish, American Academy of Sleep Medicine, abstract, 2004). We hypothesize that REM SDB is an age-related condition in women and, additionally, more prevalent in women than in men. Subjects with REM SDB were identified retrospectively among 1,540 obstructive sleep apnea (OSA) patients with an apnea-hypopnea index (AHI) >or= 5. Inclusion criteria for REM SDB were age >18, AHI >or= 5, NREM AHI < 15, and REM AHI/NREM AHI > 2. PSG data included sleep latency, REM latency, total sleep time (TST), AHI, REM AHI, NREM AHI, and sleep stage percentages. Demographic data and medical and psychiatric histories were also obtained. Statistical comparisons were made between men and women and women older and younger than 55 years, a marker for menopausal status. Two hundred twenty-one subjects fulfilled the criteria for REM SDB, yielding a prevalence of 14.4%. Overall, female apneics had a significantly higher prevalence of REM SDB than did men (24.5 vs 7.9%; p < 0.001). Younger women had a significantly higher prevalence than did older women (27.2 vs 18.6%; p = 0.008); younger men had a significantly higher prevalence of REM SDB than did older men (9.9 vs 4.5%; p = 0.002). Women were significantly older and more obese than were men. Younger women were more likely to be depressed and were significantly more obese than were older women. REM SDB is more prevalent in women than in men and more prevalent in men and women younger than 55 than those older than 55. In this population, women are more obese and older than men, while younger women were more obese

  9. Rem2, a member of the RGK family of small GTPases, is enriched in nuclei of the basal ganglia

    PubMed Central

    Liput, Daniel J.; Lu, Van B.; Davis, Margaret I.; Puhl, Henry L.; Ikeda, Stephen R.

    2016-01-01

    Rem2 is a member of the RGK subfamily of RAS small GTPases. Rem2 inhibits high voltage activated calcium channels, is involved in synaptogenesis, and regulates dendritic morphology. Rem2 is the primary RGK protein expressed in the nervous system, but to date, the precise expression patterns of this protein are unknown. In this study, we characterized Rem2 expression in the mouse nervous system. In the CNS, Rem2 mRNA was detected in all regions examined, but was enriched in the striatum. An antibody specific for Rem2 was validated using a Rem2 knockout mouse model and used to show abundant expression in striatonigral and striatopallidal medium spiny neurons but not in several interneuron populations. In the PNS, Rem2 was abundant in a subpopulation of neurons in the trigeminal and dorsal root ganglia, but was absent in sympathetic neurons of superior cervical ganglia. Under basal conditions, Rem2 was subject to post-translational phosphorylation, likely at multiple residues. Further, Rem2 mRNA and protein expression peaked at postnatal week two, which corresponds to the period of robust neuronal maturation in rodents. This study will be useful for elucidating the functions of Rem2 in basal ganglia physiology. PMID:27118437

  10. Chemogenetic inhibition of the medial prefrontal cortex reverses the effects of REM sleep loss on sucrose consumption.

    PubMed

    McEown, Kristopher; Takata, Yohko; Cherasse, Yoan; Nagata, Nanae; Aritake, Kosuke; Lazarus, Michael

    2016-12-06

    Rapid eye movement (REM) sleep loss is associated with increased consumption of weight-promoting foods. The prefrontal cortex (PFC) is thought to mediate reward anticipation. However, the precise role of the PFC in mediating reward responses to highly palatable foods (HPF) after REM sleep deprivation is unclear. We selectively reduced REM sleep in mice over a 25-48 hr period and chemogenetically inhibited the medial PFC (mPFC) by using an altered glutamate-gated and ivermectin-gated chloride channel that facilitated neuronal inhibition through hyperpolarizing infected neurons. HPF consumption was measured while the mPFC was inactivated and REM sleep loss was induced. We found that REM sleep loss increased HPF consumption compared to control animals. However, mPFC inactivation reversed the effect of REM sleep loss on sucrose consumption without affecting fat consumption. Our findings provide, for the first time, a causal link between REM sleep, mPFC function and HPF consumption.

  11. Pros and cons of solid state metering

    SciTech Connect

    Via, R.B.

    1995-10-01

    This paper addresses the problems and benefits of microprocessor based metering systems for electric power. The topics of the paper include historical aspects of power metering, mechanical meters, operating environments of power meters, reliability, cost, industry and customer acceptance, service life, and ease of adaptability to new rate structures.

  12. A dosimetry study of deuterium-deuterium neutron generator-based in vivo neutron activation analysis

    NASA Astrophysics Data System (ADS)

    Sowers, Daniel A.

    A neutron irradiation cavity for in vivo Neutron Activation Analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator which produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 x 108 +/-30% s-1. A moderator/reflector/shielding (5 cm high density polyethylene (HDPE), 5.3 cm graphite & 5.7 cm borated HDPE) assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeter (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and photon dose by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10 min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 +/- 0.8 mSv for neutron and 4.2 +/- 0.2 mSv for photon for 10 mins; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.

  13. A Dosimetry Study of Deuterium-Deuterium Neutron Generator-based In Vivo Neutron Activation Analysis.

    PubMed

    Sowers, Daniel; Liu, Yingzi; Mostafaei, Farshad; Blake, Scott; Nie, Linda H

    2015-12-01

    A neutron irradiation cavity for in vivo neutron activation analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator that produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 × 10(8) ± 30% s(-1). A moderator/reflector/shielding [5 cm high density polyethylene (HDPE), 5.3 cm graphite and 5.7 cm borated (HDPE)] assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeters (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and the photon dose was measured by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10-min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 ± 0.8 mSv for neutrons and 4.2 ± 0.2 mSv for photons for 10 min; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.

  14. Direct-reading inductance meter

    NASA Technical Reports Server (NTRS)

    Kolbly, R. B.

    1977-01-01

    Meter indicates from 30 nH to 3 micro H. Reference inductor of 15 micro H is made by winding 50 turns of Number 26 Formvar wire on Micrometal type 50-2 (or equivalent) core. Circuit eliminates requirement for complex instrument compensation prior to taking coil inductance measurement and thus is as easy to operate as common ohmmeter.

  15. A Redesigned DFA Moisture Meter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The DFA moisture meter has been internationally recognized as the standard for determining moisture content of dried fruit in general and is AOAC Official Method 972.2 for measuring moisture in prunes and raisins since 1972. The device has remained virtually unchanged since its inception, with its o...

  16. REM sleep behavior disorder: Updated review of the core features, the REM sleep behavior disorder-neurodegenerative disease association, evolving concepts, controversies, and future directions.

    PubMed

    Boeve, Bradley F

    2010-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia manifested by vivid, often frightening dreams associated with simple or complex motor behavior during REM sleep. The polysomnographic features of RBD include increased electromyographic tone +/- dream enactment behavior during REM sleep. Management with counseling and pharmacologic measures is usually straightforward and effective. In this review, the terminology, clinical and polysomnographic features, demographic and epidemiologic features, diagnostic criteria, differential diagnosis, and management strategies are discussed. Recent data on the suspected pathophysiologic mechanisms of RBD are also reviewed. The literature and our institutional experience on RBD are next discussed, with an emphasis on the RBD-neurodegenerative disease association and particularly the RBD-synucleinopathy association. Several issues relating to evolving concepts, controversies, and future directions are then reviewed, with an emphasis on idiopathic RBD representing an early feature of a neurodegenerative disease and particularly an evolving synucleinopathy. Planning for future therapies that impact patients with idiopathic RBD is reviewed in detail.

  17. Neutron detector

    DOEpatents

    Stephan, Andrew C.; Jardret; Vincent D.

    2011-04-05

    A neutron detector has a volume of neutron moderating material and a plurality of individual neutron sensing elements dispersed at selected locations throughout the moderator, and particularly arranged so that some of the detecting elements are closer to the surface of the moderator assembly and others are more deeply embedded. The arrangement captures some thermalized neutrons that might otherwise be scattered away from a single, centrally located detector element. Different geometrical arrangements may be used while preserving its fundamental characteristics. Different types of neutron sensing elements may be used, which may operate on any of a number of physical principles to perform the function of sensing a neutron, either by a capture or a scattering reaction, and converting that reaction to a detectable signal. High detection efficiency, an ability to acquire spectral information, and directional sensitivity may be obtained.

  18. Augmented In Situ Subsurface Bioremediation Process™BIO-REM, Inc. - Demonstration Bulletin

    EPA Science Inventory

    The Augmented In Situ Subsurface Bioremediation Process™ developed by BIO-REM, Inc., uses microaerophilic bacteria and micronutrients (H-10) and surface tension depressants/penetrants for the treatment of hydrocarbon contaminated soils and groundwater. The bacteria utilize hydroc...

  19. REM sleep and emotional face memory in typically-developing children and children with autism.

    PubMed

    Tessier, Sophie; Lambert, Andréane; Scherzer, Peter; Jemel, Boutheina; Godbout, Roger

    2015-09-01

    Relationship between REM sleep and memory was assessed in 13 neurotypical and 13 children with Autistic Spectrum Disorder (ASD). A neutral/positive/negative face recognition task was administered the evening before (learning and immediate recognition) and the morning after (delayed recognition) sleep. The number of rapid eye movements (REMs), beta and theta EEG activity over the visual areas were measured during REM sleep. Compared to neurotypical children, children with ASD showed more theta activity and longer reaction time (RT) for correct responses in delayed recognition of neutral faces. Both groups showed a positive correlation between sleep and performance but different patterns emerged: in neurotypical children, accuracy for recalling neutral faces and overall RT improvement overnight was correlated with EEG activity and REMs; in children with ASD, overnight RT improvement for positive and negative faces correlated with theta and beta activity, respectively. These results suggest that neurotypical and children with ASD use different sleep-related brain networks to process faces.

  20. The hypocretins (orexins) mediate the “phasic” components of REM sleep: A new hypothesis

    PubMed Central

    Torterolo, Pablo; Chase, Michael H.

    2014-01-01

    In 1998, a group of phenotypically distinct neurons were discovered in the postero-lateral hypothalamus which contained the neuropeptides hypocretin 1 and hypocretin 2 (also called orexin A and orexin B), which are excitatory neuromodulators. Hypocretinergic neurons project throughout the central nervous system and have been involved in the generation and maintenance of wakefulness. The sleep disorder narcolepsy, characterized by hypersomnia and cataplexy, is produced by degeneration of these neurons. The hypocretinergic neurons are active during wakefulness in conjunction with the presence of motor activity that occurs during survival-related behaviors. These neurons decrease their firing rate during non-REM sleep; however there is still controversy upon the activity and role of these neurons during REM sleep. Hence, in the present report we conducted a critical review of the literature of the hypocretinergic system during REM sleep, and hypothesize a possible role of this system in the generation of REM sleep. PMID:26483897

  1. Differential modulation of global and local neural oscillations in REM sleep by homeostatic sleep regulation

    PubMed Central

    Kim, Bowon; Kocsis, Bernat; Hwang, Eunjin; Kim, Youngsoo; Strecker, Robert E.; McCarley, Robert W.; Choi, Jee Hyun

    2017-01-01

    Homeostatic rebound in rapid eye movement (REM) sleep normally occurs after acute sleep deprivation, but REM sleep rebound settles on a persistently elevated level despite continued accumulation of REM sleep debt during chronic sleep restriction (CSR). Using high-density EEG in mice, we studied how this pattern of global regulation is implemented in cortical regions with different functions and network architectures. We found that across all areas, slow oscillations repeated the behavioral pattern of persistent enhancement during CSR, whereas high-frequency oscillations showed progressive increases. This pattern followed a common rule despite marked topographic differences. The findings suggest that REM sleep slow oscillations may translate top-down homeostatic control to widely separated brain regions whereas fast oscillations synchronizing local neuronal ensembles escape this global command. These patterns of EEG oscillation changes are interpreted to reconcile two prevailing theories of the function of sleep, synaptic homeostasis and sleep dependent memory consolidation. PMID:28193862

  2. Managing resident to resident elder mistreatment (R-REM) in nursing homes: the SEARCH approach

    PubMed Central

    Ellis, Julie; Teresi, Jeanne A.; Ramirez, Mildred; Silver, Stephanie; Boratgis, Gabriel; Kong, Jian; Eimicke, Joseph P.; Sukha, Gail; Lachs, Mark S.; Pillemer, Karl A.

    2014-01-01

    This article describes an educational program to inform nursing and care staff in the management of resident-to-resident elder mistreatment (R-REM) in nursing homes, using the SEARCH approach. Although relatively little research has been conducted on this form of abuse, there is mounting interest in R-REM, as such aggression has been found to be extensive and can have both physical and psychological consequences for residents and staff. The aim of the SEARCH approach is to support staff in the identification and recognition of R-REM, and suggesting recommendations for management. The education program and the SEARCH approach are described. Three case studies from the research project are presented, illustrating how the SEARCH approach can be used by nurses and care staff to manage R-REM in nursing homes. Resident- and staff safety and well-being can be enhanced by the use of the evidence-based SEARCH approach. PMID:24548656

  3. Restoration of normal motor control in Parkinson's disease during REM sleep.

    PubMed

    De Cock, Valérie Cochen; Vidailhet, Marie; Leu, Smaranda; Texeira, Antonio; Apartis, Emmanuelle; Elbaz, Alexis; Roze, Emmanuel; Willer, Jean Claude; Derenne, Jean Philippe; Agid, Yves; Arnulf, Isabelle

    2007-02-01

    Although normal subjects do not move during REM sleep, patients with Parkinson's disease may experience REM sleep behaviour disorder (RBD). The characteristics of the abnormal REM sleep movements in RBD have, however, not been studied. We interviewed one hundred consecutive non-demented patients with Parkinson's disease and their bed partners using a structured questionnaire assessing the presence of RBD. They rated the quality of movements, voice and facial expression during RBD as being better, equal or worse than in awake ON levodopa condition. Night-time sleep and movements were video-monitored during polysomnography in 51 patients to evaluate the presence of bradykinesia, tremor and hypophonia during REM sleep. Fifty-nine patients had clinical RBD with 53/59 bed partners able to evaluate them. All 53 (100%) reported an improvement of at least one component of motor control during RBD. By history, movements were improved in 87% patients (faster, 87%; stronger, 87%; smoother, 51%), speech was better in 77% patients (more intelligible, 77%; louder, 38%; better articulated, 57%) and facial expression was normalized in 47% patients. Thirty-eight per cent of bed partners reported that movements were 'much better', even in the most disabled patients. The video-monitored purposeful movements in REM sleep were also surprisingly fast, ample, coordinated and symmetrical, without obvious sign of parkinsonism. The movements were, however, jerky, violent and often repetitive. While all patients had asymmetrical parkinsonism when awake, most of the time they used the more disabled arm, hand and leg during the RBD (P = 0.04). Movements involved six times as often the upper limbs and the face as the lower limbs (OR: 5.9, P = 0.004). The percentage of time containing tremor EMG activity decreased with sleep stages from 34.9 +/- 15.5% during wakefulness, to 3.6 +/- 5.7% during non-REM sleep stages 1-2, 1.4 +/- 3.0% during non-REM sleep stages 3-4, and 0.06 +/- 0.2% during REM

  4. The predictive value of Muller maneuver in REM-dependent obstructive sleep apnea.

    PubMed

    Ozcan, Kursat Murat; Ozcan, Muge; Ozdogan, Fatih; Hizli, Omer; Dere, Huseyin; Unal, Adnan

    2013-09-01

    To our knowledge, no studies up to date have investigated the correlation of rapid eye movement (REM) dependent obstructive sleep apnea syndrome (OSAS) and Muller maneuver. The aim of this study is to investigate whether REM-dependent OSAS is predicted by the findings of the Muller maneuver. The study was conducted on 149 patients with witnessed apnea and daytime sleepiness. Muller maneuver was performed to all patients and the obstruction site was determined using a five-point scale. Then, polysomnography of the patient was obtained and the apnea-hypopnea indexes were determined in total sleep time, REM-dependent sleep and non-REM-dependent sleep. The correlations between the Muller maneuver findings and polysomnographic data were analyzed. The ages of the patients included in the study ranged between 25 and 73 years with a mean age of 49.3 ± 10.1 years. Their mean body mass index was 30.8 ± 5.1 kg/m(2) (range 21.9-55.4 kg/m(2)). The patients' mean apnea-hypopnea indexes in total sleep time was 28.1 and ranged between 5.4 and 124.3. REM-dependent OSAS was determined in 49 patients. When the data were analyzed, it was determined that there were no statistically significant correlations between tongue base or lateral pharyngeal band obstruction at the level of hypopharynx and the REM-dependent OSAS. At the level of the soft palate, the obstruction caused by the lateral pharyngeal bands or soft palate and REM dependency did not show any statistically significant correlation (p > 0.05). In conclusion, Muller maneuver does not provide useful data to predict REM dependency of OSAS.

  5. 'REM-related OSA': a forgotten diagnostic? Possible path to under-diagnosing sleep apnea.

    PubMed

    Beneto, A; Soler-Algarra, S; Salavert, V

    2016-12-01

    Introduccion. Recientemente se han propugnado criterios restrictivos para definir el sindrome de apnea/hipopnea obstructiva ligado al sueño REM y persisten interrogantes sobre su trascendencia nosologica y manejo clinico. Objetivo. Evaluar los criterios definitorios de la apnea del sueño REM, su relacion con la comorbilidad cardiometabolica y los aspectos relacionados con su diagnostico. Pacientes y metodos. Estudio observacional retrospectivo sobre datos clinicos y polisomnograficos de pacientes ambulatorios. Se incluyo a 525 pacientes mayores de 18 años que tenian un indice apnea/hipopnea (IAH) por hora de sueño = 5 (total, o parcial en REM o no REM). Resultados. Se han configurado subgrupos 'dependientes de la fase' utilizando un criterio basado en la 'proporcion = 2' y otro 'estricto' basado en uno de los IAH parciales = 5 frente al otro IAH < 5 (en REM o en no REM). En el subgrupo 'apnea del sueño REM estricto', la mitad de los pacientes muestra un IAH global < 5 y menos gravedad en los parametros respiratorios, pero sin menores porcentajes de comorbilidad. Con los criterios diagnosticos actuales quedarian excluidos del diagnostico de sindrome de apnea/hipopnea obstructiva del sueño (SAHOS). Conclusiones. Aplicar un criterio estricto para detectar apnea del sueño REM permite filtrar formas muy leves de SAHOS asociadas a comorbilidad cardiometabolica en porcentajes no diferentes significativamente de otras formas mas graves. Para evitar el infradiagnostico del SAHOS seria oportuno revisar los criterios diagnosticos actuales y las indicaciones de las tecnicas reducidas.

  6. Assessing the Dream-Lag Effect for REM and NREM Stage 2 Dreams

    PubMed Central

    Blagrove, Mark; Fouquet, Nathalie C.; Henley-Einion, Josephine A.; Pace-Schott, Edward F.; Davies, Anna C.; Neuschaffer, Jennifer L.; Turnbull, Oliver H.

    2011-01-01

    This study investigates evidence, from dream reports, for memory consolidation during sleep. It is well-known that events and memories from waking life can be incorporated into dreams. These incorporations can be a literal replication of what occurred in waking life, or, more often, they can be partial or indirect. Two types of temporal relationship have been found to characterize the time of occurrence of a daytime event and the reappearance or incorporation of its features in a dream. These temporal relationships are referred to as the day-residue or immediate incorporation effect, where there is the reappearance of features from events occurring on the immediately preceding day, and the dream-lag effect, where there is the reappearance of features from events occurring 5–7 days prior to the dream. Previous work on the dream-lag effect has used spontaneous home recalled dream reports, which can be from Rapid Eye Movement Sleep (REM) and from non-Rapid Eye Movement Sleep (NREM). This study addresses whether the dream-lag effect occurs only for REM sleep dreams, or for both REM and NREM stage 2 (N2) dreams. 20 participants kept a daily diary for over a week before sleeping in the sleep laboratory for 2 nights. REM and N2 dreams collected in the laboratory were transcribed and each participant rated the level of correspondence between every dream report and every diary record. The dream-lag effect was found for REM but not N2 dreams. Further analysis indicated that this result was not due to N2 dream reports being shorter, in terms of number of words, than the REM dream reports. These results provide evidence for a 7-day sleep-dependent non-linear memory consolidation process that is specific to REM sleep, and accord with proposals for the importance of REM sleep to emotional memory consolidation. PMID:22046336

  7. Melanin-Concentrating Hormone (MCH): Role in REM Sleep and Depression

    PubMed Central

    Torterolo, Pablo; Scorza, Cecilia; Lagos, Patricia; Urbanavicius, Jessika; Benedetto, Luciana; Pascovich, Claudia; López-Hill, Ximena; Chase, Michael H.; Monti, Jaime M.

    2015-01-01

    The melanin-concentrating hormone (MCH) is a peptidergic neuromodulator synthesized by neurons of the lateral sector of the posterior hypothalamus and zona incerta. MCHergic neurons project throughout the central nervous system, including areas such as the dorsal (DR) and median (MR) raphe nuclei, which are involved in the control of sleep and mood. Major Depression (MD) is a prevalent psychiatric disease diagnosed on the basis of symptomatic criteria such as sadness or melancholia, guilt, irritability, and anhedonia. A short REM sleep latency (i.e., the interval between sleep onset and the first REM sleep period), as well as an increase in the duration of REM sleep and the density of rapid-eye movements during this state, are considered important biological markers of depression. The fact that the greatest firing rate of MCHergic neurons occurs during REM sleep and that optogenetic stimulation of these neurons induces sleep, tends to indicate that MCH plays a critical role in the generation and maintenance of sleep, especially REM sleep. In addition, the acute microinjection of MCH into the DR promotes REM sleep, while immunoneutralization of this peptide within the DR decreases the time spent in this state. Moreover, microinjections of MCH into either the DR or MR promote a depressive-like behavior. In the DR, this effect is prevented by the systemic administration of antidepressant drugs (either fluoxetine or nortriptyline) and blocked by the intra-DR microinjection of a specific MCH receptor antagonist. Using electrophysiological and microdialysis techniques we demonstrated also that MCH decreases the activity of serotonergic DR neurons. Therefore, there are substantive experimental data suggesting that the MCHergic system plays a role in the control of REM sleep and, in addition, in the pathophysiology of depression. Consequently, in the present report, we summarize and evaluate the current data and hypotheses related to the role of MCH in REM sleep and MD

  8. GABA(A) receptors implicated in REM sleep control express a benzodiazepine binding site.

    PubMed

    Nguyen, Tin Quang; Liang, Chang-Lin; Marks, Gerald A

    2013-08-21

    It has been reported that non-subtype-selective GABAA receptor antagonists injected into the nucleus pontis oralis (PnO) of rats induced long-lasting increases in REM sleep. Characteristics of these REM sleep increases were identical to those resulting from injection of muscarinic cholinergic agonists. Both actions were blocked by the muscarinic antagonist, atropine. Microdialysis of GABAA receptor antagonists into the PnO resulted in increased acetylcholine levels. These findings were consistent with GABAA receptor antagonists disinhibiting acetylcholine release in the PnO to result in an acetylcholine-mediated REM sleep induction. Direct evidence has been lacking for localization in the PnO of the specific GABAA receptor-subtypes mediating the REM sleep effects. Here, we demonstrated a dose-related, long-lasting increase in REM sleep following injection (60 nl) in the PnO of the inverse benzodiazepine agonist, methyl-6,7-dimethoxy-4-ethyl-β-carboline (DMCM, 10(-2)M). REM sleep increases were greater and more consistently produced than with the non-selective antagonist gabazine, and both were blocked by atropine. Fluorescence immunohistochemistry and laser scanning confocal microscopy, colocalized in PnO vesicular acetylcholine transporter, a presynaptic marker of cholinergic boutons, with the γ2 subunit of the GABAA receptor. These data provide support for the direct action of GABA on mechanisms of acetylcholine release in the PnO. The presence of the γ2 subunit at this locus and the REM sleep induction by DMCM are consistent with binding of benzodiazepines by a GABAA receptor-subtype in control of REM sleep.

  9. Assessing the dream-lag effect for REM and NREM stage 2 dreams.

    PubMed

    Blagrove, Mark; Fouquet, Nathalie C; Henley-Einion, Josephine A; Pace-Schott, Edward F; Davies, Anna C; Neuschaffer, Jennifer L; Turnbull, Oliver H

    2011-01-01

    This study investigates evidence, from dream reports, for memory consolidation during sleep. It is well-known that events and memories from waking life can be incorporated into dreams. These incorporations can be a literal replication of what occurred in waking life, or, more often, they can be partial or indirect. Two types of temporal relationship have been found to characterize the time of occurrence of a daytime event and the reappearance or incorporation of its features in a dream. These temporal relationships are referred to as the day-residue or immediate incorporation effect, where there is the reappearance of features from events occurring on the immediately preceding day, and the dream-lag effect, where there is the reappearance of features from events occurring 5-7 days prior to the dream. Previous work on the dream-lag effect has used spontaneous home recalled dream reports, which can be from Rapid Eye Movement Sleep (REM) and from non-Rapid Eye Movement Sleep (NREM). This study addresses whether the dream-lag effect occurs only for REM sleep dreams, or for both REM and NREM stage 2 (N2) dreams. 20 participants kept a daily diary for over a week before sleeping in the sleep laboratory for 2 nights. REM and N2 dreams collected in the laboratory were transcribed and each participant rated the level of correspondence between every dream report and every diary record. The dream-lag effect was found for REM but not N2 dreams. Further analysis indicated that this result was not due to N2 dream reports being shorter, in terms of number of words, than the REM dream reports. These results provide evidence for a 7-day sleep-dependent non-linear memory consolidation process that is specific to REM sleep, and accord with proposals for the importance of REM sleep to emotional memory consolidation.

  10. Medullary circuitry regulating rapid eye movement (REM) sleep and motor atonia

    PubMed Central

    Vetrivelan, Ramalingam; Fuller, Patrick M; Tong, Qingchun; Lu, Jun

    2009-01-01

    Considerable data support a role for glycinergic ventromedial medulla neurons in the mediation of the postsynaptic inhibition of spinal motoneurons necessary for the motor atonia of rapid-eye movement (REM) sleep in cats. These data are however difficult to reconcile with the fact that large lesions of the rostral ventral medulla do not result in loss of REM atonia in rats. In the present study, we sought to clarify which medullary networks in rodents are responsible for REM motor atonia by retrogradely tracing inputs to the spinal ventral horn from the medulla, ablating these medullary sources to determine their effects on REM atonia and using transgenic mice to identify the neurotransmitter(s) involved. Our results reveal a restricted region within the ventromedial medulla, termed here the ‘supraolivary medulla’ (SOM), which contains glutamatergic neurons that project to the spinal ventral horn. Cell-body specific lesions of the SOM resulted in an intermittent loss of muscle atonia, taking the form of exaggerated phasic muscle twitches, during REM sleep. A concomitant reduction in REM sleep time was observed in the SOM-lesioned animals. We next used mice with lox-P modified alleles of either the glutamate or GABA/glycine vesicular transporters to selectively eliminate glutamate or GABA/glycine neurotransmission from SOM neurons. Loss of SOM glutamate release, but not SOM GABA/glycine release, resulted in exaggerated muscle twitches during REM sleep that were similar to those observed following SOM lesions in rats. These findings, taken together, demonstrate that SOM glutamatergic neurons comprise key elements of the medullary circuitry mediating REM atonia. PMID:19625526

  11. Atmospheric neutrons

    NASA Technical Reports Server (NTRS)

    Preszler, A. M.; Moon, S.; White, R. S.

    1976-01-01

    Additional calibrations of the University of California double-scatter neutron detector and additional analysis corrections lead to slightly changed neutron fluxes. The theoretical angular distributions of Merker (1975) are in general agreement with the reported experimental fluxes but do not give the peaks for vertical upward and downward moving neutrons. The theoretical neutron escape current is in agreement with the experimental values from 10 to 100 MeV. The experimental fluxes obtained agree with those of Kanbach et al. (1974) in the overlap region from 70 to 100 MeV.

  12. Loss of Gnas imprinting differentially affects REM/NREM sleep and cognition in mice.

    PubMed

    Lassi, Glenda; Ball, Simon T; Maggi, Silvia; Colonna, Giovanni; Nieus, Thierry; Cero, Cheryl; Bartolomucci, Alessandro; Peters, Jo; Tucci, Valter

    2012-01-01

    It has been suggested that imprinted genes are important in the regulation of sleep. However, the fundamental question of whether genomic imprinting has a role in sleep has remained elusive up to now. In this work we show that REM and NREM sleep states are differentially modulated by the maternally expressed imprinted gene Gnas. In particular, in mice with loss of imprinting of Gnas, NREM and complex cognitive processes are enhanced while REM and REM-linked behaviors are inhibited. This is the first demonstration that a specific overexpression of an imprinted gene affects sleep states and related complex behavioral traits. Furthermore, in parallel to the Gnas overexpression, we have observed an overexpression of Ucp1 in interscapular brown adipose tissue (BAT) and a significant increase in thermoregulation that may account for the REM/NREM sleep phenotypes. We conclude that there must be significant evolutionary advantages in the monoallelic expression of Gnas for REM sleep and for the consolidation of REM-dependent memories. Conversely, biallelic expression of Gnas reinforces slow wave activity in NREM sleep, and this results in a reduction of uncertainty in temporal decision-making processes.

  13. REM sleep de-potentiates amygdala activity to previous emotional experiences

    PubMed Central

    van der Helm, Els; Yao, Justin; Dutt, Shubir; Rao, Vikram; Saletin, Jared M.; Walker, Matthew P.

    2011-01-01

    Summary Clinical evidence suggests a potentially causal interaction between sleep and affective brain function; nearly all mood disorders display co-occurring sleep abnormalities, commonly involving rapid-eye movement (REM) sleep [1–4]. Building on this clinical evidence, recent neurobiological frameworks have hypothesized a benefit of REM sleep in palliatively decreasing next-day brain reactivity to recent waking emotional experiences [5, 6]. Specifically, the marked suppression of central adrenergic neurotransmitters during REM (commonly implicated in arousal and stress), coupled with activation in amygdala-hippocampal networks that encode salient events, is proposed to (re)process and de-potentiate previous affective experiences, decreasing their emotional intensity [3]. In contrast, the failure of such adrenergic reduction during REM sleep has been described in anxiety disorders, indexed by persistent high-frequency electroencephalographic (EEG) activity (>30Hz) [7–10]; a candidate factor contributing to hyper-arousal and exaggerated amygdala reactivity [3, 11–13]. Despite these neurobiological frameworks, and their predictions, the proposed benefit of REM sleep physiology in de-potentiating neural and behavioral responsivity to prior emotional events remains unknown. Here, we demonstrate that REM sleep physiology is associated with an overnight dissipation of amygdala activity in response to previous emotional experiences, altering functional-connectivity and reducing next-day subjective emotionality. PMID:22119526

  14. Bioanalysis young investigator: Alexander Medina-Remón.

    PubMed

    Medina-Remón, Alexander; Raventós, Rosa Maria Lamuela

    2011-07-01

    Supervisor's supporting comments Alex Medina joined my research group, Natural Antioxidants, in January 2006 to start his PhD program. He has been working intensively and efficiently on several projects; initially for his thesis he developed a new bioanalytical methodology to quantify phenols in urine (Medina-Remón A et al. 2009) to correlate with the hypertension prevention in the PREDIMED study ( www.predimed.org ). Thanks to this new bioanalytical method, we are currently starting collaboration projects with different research centers. In addition, he has been working on other research projects on tomatoes, grapes, citric fruits and wine. Medina is helpful whenever needed and efficient. He has shown himself to be responsible, well-prepared, intelligent, organized and to have very good teaching skills. Moreover, he is patient and able to solve problems calmly, but at the same time, he is enthusiastic about what he does and can transmit this enthusiasm to his colleagues. He is really a thoughtful scientist. I have now contracted him as a Postdoctoral researcher. His responsibilities include leading several master's students and he is writing several papers on the health effects of polyphenols using his method.

  15. UV Opacity at Gale Crater from MSL/REMS Measurements

    NASA Astrophysics Data System (ADS)

    Vicente-Retortillo, Á.; Martinez, G.; Renno, N. O.; Lemmon, M. T.; Mason, E. L.; de la Torre-Juárez, M.

    2015-12-01

    We use the UV photodiode output currents (TELRDR products) measured by the REMS Ultraviolet Sensor to calculate UV opacities at Gale crater during the first 804 sols of the MSL mission. We propose a novel technique to calculate the atmospheric opacity that is not sensitive to the degradation of the sensor due to the deposition of dust on it. We estimate the diffuse and total radiation signals by analyzing the events in which the direct solar beam was temporarily blocked by the masthead or by the mast of the rover. Then we use a radiative transfer model based on the Monte-Carlo method to obtain the UV opacity from those measurements. We compare the UV opacities with the opacities derived from Mastcam observations at 880 nm. Both opacities follow a similar seasonal trend, with the UV opacity showing values generally lower than those at 880 nm. The difference between both opacities varies over the year, with the minimum difference occurring when both opacities show their annual lowest values (Ls ~ 130º). The temporal variation of this difference may be attributed to changes in the dust size distribution.

  16. Federal Building Metering Guidance (per 42 U.S.C. 8253(e), Metering of Energy Use)

    SciTech Connect

    2014-11-01

    Guidance defines which federal buildings are appropriate to meter, provides metering prioritization recommendations for agencies with limited resources, and discusses the requirement for agencies to submit metering implementation plans to the U.S. Department of Energy.

  17. Government Program Briefing: Smart Metering

    SciTech Connect

    Doris, E.; Peterson, K.

    2011-09-01

    This document is adapted and updated from a memo delivered to the City Council of New Orleans, the office of the Mayor of New Orleans, the Chairperson of the Citizen Stakeholders Group (New Orleans Energy Task Force) and the U.S. Department of Energy (DOE) Project Officer in March 2008. This briefing piece provides an overview of the benefits, costs, and challenges of smart metering.

  18. Reflective-tube absorption meter

    NASA Astrophysics Data System (ADS)

    Zaneveld, J. Ronald V.; Bartz, Robert; Kitchen, James C.

    1990-09-01

    The design and calibration of a proposed in situ spectral absorption meter is evaluated using a laboratory prototype. The design includes a silver coated (second-surface) glass tube, a tungsten light source (stabilized by means of optical feedback), a monochromator, and a solid state detector. The device measures the absorption coefficient plus a portion of the volume scattering function. Theoretical analyses and laboratory experiments which explore the magnitude and variation of the errors due to scattering and internal reflections are described. Similar analyses are performed on the Cary 1 18 Spectrophotometer to allow cross calibration. Algorithms to yield the abscrption coefficient and the zenith-sun diffuse attenuation coefficient are presented and evaluated. Simultaneous measurement of the beam attenuation or backscattering coefficient allows use of algoriThms with much narrower error bands. The various methods of obtaining absorption and diffuse attenuation values are compared. Procedures for using reverse osmosis filtration to produce a clean water calibration standard are described. An absorption spectrum for pure water is obtained. Development of the absorption meter is proceeding along two lines: 1) a two-wavelength side-by-side LED is being fabricated to allow an in situ chlorophyll a absorption meter to be constructed, and 2) scientific projects using a shipboard or laboratory flow.-through pumping system are being planned.

  19. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  20. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Zinn, W.H.; Anderson, H.L.

    1958-09-16

    Means are presenied for increasing the reproduction ratio of a gaphite- moderated neutronic reactor by diminishing the neutron loss due to absorption or capture by gaseous impurities within the reactor. This means comprised of a fluid-tight casing or envelope completely enclosing the reactor and provided with a valve through which the casing, and thereby the reactor, may be evacuated of atmospheric air.

  1. Neutron tubes

    DOEpatents

    Leung, Ka-Ngo; Lou, Tak Pui; Reijonen, Jani

    2008-03-11

    A neutron tube or generator is based on a RF driven plasma ion source having a quartz or other chamber surrounded by an external RF antenna. A deuterium or mixed deuterium/tritium (or even just a tritium) plasma is generated in the chamber and D or D/T (or T) ions are extracted from the plasma. A neutron generating target is positioned so that the ion beam is incident thereon and loads the target. Incident ions cause D-D or D-T (or T-T) reactions which generate neutrons. Various embodiments differ primarily in size of the chamber and position and shape of the neutron generating target. Some neutron generators are small enough for implantation in the body. The target may be at the end of a catheter-like drift tube. The target may have a tapered or conical surface to increase target surface area.

  2. Neutron source

    DOEpatents

    Cason, J.L. Jr.; Shaw, C.B.

    1975-10-21

    A neutron source which is particularly useful for neutron radiography consists of a vessel containing a moderating media of relatively low moderating ratio, a flux trap including a moderating media of relatively high moderating ratio at the center of the vessel, a shell of depleted uranium dioxide surrounding the moderating media of relatively high moderating ratio, a plurality of guide tubes each containing a movable source of neutrons surrounding the flux trap, a neutron shield surrounding one part of each guide tube, and at least one collimator extending from the flux trap to the exterior of the neutron source. The shell of depleted uranium dioxide has a window provided with depleted uranium dioxide shutters for each collimator. Reflectors are provided above and below the flux trap and on the guide tubes away from the flux trap.

  3. Cross-cultural differences in meter perception.

    PubMed

    Kalender, Beste; Trehub, Sandra E; Schellenberg, E Glenn

    2013-03-01

    We examined the influence of incidental exposure to varied metrical patterns from different musical cultures on the perception of complex metrical structures from an unfamiliar musical culture. Adults who were familiar with Western music only (i.e., simple meters) and those who also had limited familiarity with non-Western music were tested on their perception of metrical organization in unfamiliar (Turkish) music with simple and complex meters. Adults who were familiar with Western music detected meter-violating changes in Turkish music with simple meter but not in Turkish music with complex meter. Adults with some exposure to non-Western music that was unmetered or metrically complex detected meter-violating changes in Turkish music with both simple and complex meters, but they performed better on patterns with a simple meter. The implication is that familiarity with varied metrical structures, including those with a non-isochronous tactus, enhances sensitivity to the metrical organization of unfamiliar music.

  4. 1-Meter Digital Elevation Model specification

    USGS Publications Warehouse

    Arundel, Samantha T.; Archuleta, Christy-Ann M.; Phillips, Lori A.; Roche, Brittany L.; Constance, Eric W.

    2015-10-21

    In January 2015, the U.S. Geological Survey National Geospatial Technical Operations Center began producing the 1-Meter Digital Elevation Model data product. This new product was developed to provide high resolution bare-earth digital elevation models from light detection and ranging (lidar) elevation data and other elevation data collected over the conterminous United States (lower 48 States), Hawaii, and potentially Alaska and the U.S. territories. The 1-Meter Digital Elevation Model consists of hydroflattened, topographic bare-earth raster digital elevation models, with a 1-meter x 1-meter cell size, and is available in 10,000-meter x 10,000-meter square blocks with a 6-meter overlap. This report details the specifications required for the production of the 1-Meter Digital Elevation Model.

  5. How to use your peak flow meter

    MedlinePlus

    ... get your child used to them. Find Your Personal Best To find your personal best peak flow ... peak flow meter; Bronchial asthma - peak flow meter Images How to measure peak flow References Durrani SR, ...

  6. Parkinson risk in idiopathic REM sleep behavior disorder

    PubMed Central

    Postuma, Ronald B.; Gagnon, Jean-Francois; Bertrand, Josie-Anne; Génier Marchand, Daphné

    2015-01-01

    Objective: To precisely delineate clinical risk factors for conversion from idiopathic REM sleep behavior disorder (RBD) to Parkinson disease, dementia with Lewy bodies, and multiple system atrophy, in order to enable practical planning and stratification of neuroprotective trials against neurodegenerative synucleinopathy. Methods: In a 10-year prospective cohort, we tested prodromal Parkinson disease markers in 89 patients with idiopathic RBD. With Kaplan-Meier analysis, we calculated risk of neurodegenerative synucleinopathy, and using Cox proportional hazards, tested the ability of prodromal markers to identify patients at higher disease risk. By combining predictive markers, we then designed stratification strategies to optimally select patients for definitive neuroprotective trials. Results: The risk of defined neurodegenerative synucleinopathy was high: 30% developed disease at 3 years, rising to 66% at 7.5 years. Advanced age (hazard ratio [HR] = 1.07), olfactory loss (HR = 2.8), abnormal color vision (HR = 3.1), subtle motor dysfunction (HR = 3.9), and nonuse of antidepressants (HR = 3.5) identified higher risk of disease conversion. However, mild cognitive impairment (HR = 1.8), depression (HR = 0.63), Parkinson personality, treatment with clonazepam (HR = 1.3) or melatonin (HR = 0.55), autonomic markers, and sex (HR = 1.37) did not clearly predict clinical neurodegeneration. Stratification with prodromal markers increased risk of neurodegenerative disease conversion by 200%, and combining markers allowed sample size reduction in neuroprotective trials by >40%. With a moderately effective agent (HR = 0.5), trials with fewer than 80 subjects per group can demonstrate definitive reductions in neurodegenerative disease. Conclusions: Using stratification with simply assessed markers, it is now not only possible, but practical to include patients with RBD in neuroprotective trials against Parkinson disease, multiple system atrophy, and dementia with Lewy bodies

  7. Myotonic dystrophy type 1, daytime sleepiness and REM sleep dysregulation.

    PubMed

    Dauvilliers, Yves A; Laberge, Luc

    2012-12-01

    Myotonic dystrophy type 1 (DM1), or Steinert's disease, is the most common adult-onset form of muscular dystrophy. DM1 also constitutes the neuromuscular condition with the most significant sleep disorders including excessive daytime sleepiness (EDS), central and obstructive sleep apneas, restless legs syndrome (RLS), periodic leg movements in wake (PLMW) and periodic leg movements in sleep (PLMS) as well as nocturnal and diurnal rapid eye movement (REM) sleep dysregulation. EDS is the most frequent non-muscular complaint in DM1, being present in about 70-80% of patients. Different phenotypes of sleep-related problems may mimic several sleep disorders, including idiopathic hypersomnia, narcolepsy without cataplexy, sleep apnea syndrome, and periodic leg movement disorder. Subjective and objective daytime sleepiness may be associated with the degree of muscular impairment. However, available evidence suggests that DM1-related EDS is primarily caused by a central dysfunction of sleep regulation rather than by sleep fragmentation, sleep-related respiratory events or periodic leg movements. EDS also tends to persist despite successful treatment of sleep-disordered breathing in DM1 patients. As EDS clearly impacts on physical and social functioning of DM1 patients, studies are needed to identify the best appropriate tools to identify hypersomnia, and clarify the indications for polysomnography (PSG) and multiple sleep latency test (MSLT) in DM1. In addition, further structured trials of assisted nocturnal ventilation and randomized trials of central nervous system (CNS) stimulant drugs in large samples of DM1 patients are required to optimally treat patients affected by this progressive, incurable condition.

  8. The Evolution of REM Sleep Behavior Disorder in Early Parkinson Disease

    PubMed Central

    Sixel-Döring, Friederike; Zimmermann, Johannes; Wegener, Andrea; Mollenhauer, Brit; Trenkwalder, Claudia

    2016-01-01

    Study Objectives: To investigate the development of REM sleep behavior disorder (RBD) and REM sleep behavioral events (RBE) not yet fulfilling diagnostic criteria for RBD as markers for neurodegeneration in a cohort of Parkinson disease (PD) patients between their de novo baseline assessment and two-year follow-up in comparison to healthy controls (HC). Methods: Clinically confirmed PD patients and HC with video-supported polysomnography (vPSG) data at baseline were re-investigated after two years. Diagnostic scoring for RBE and RBD was performed in both groups and related to baseline findings. Results: One hundred thirteen PD patients and 102 healthy controls (HC) were included in the study. Within two years, the overall occurrence of behaviors during REM sleep in PD patients increased from 50% to 63% (P = 0.02). RBD increased from 25% to 43% (P < 0.001). Eleven of 29 (38%) RBE positive PD patients and 10/56 (18%) patients with normal REM sleep at baseline converted to RBD. In HC, the occurrence of any REM behavior increased from 17% to 20% (n.s.). RBD increased from 2% to 4% (n.s.). One of 15 (7%) RBE positive HC and 1/85 (1%) HC with normal REM at baseline converted to RBD. Conclusions: RBD increased significantly in PD patients from the de novo state to two-year follow-up. We propose RBE being named “prodromal RBD” as it may follow a continuous evolution in PD possibly similar to the spreading of Lewy bodies in PD patients. RBD itself was shown as a robust and stable marker of early PD. Citation: Sixel-Döring F, Zimmermann J, Wegener A, Mollenhauer B, Trenkwalder C. The evolution of REM sleep behavior disorder in early Parkinson disease. SLEEP 2016;39(9):1737–1742. PMID:27306265

  9. Brain prolactin is involved in stress-induced REM sleep rebound.

    PubMed

    Machado, Ricardo Borges; Rocha, Murilo Ramos; Suchecki, Deborah

    2017-03-01

    REM sleep rebound is a common behavioural response to some stressors and represents an adaptive coping strategy. Animals submitted to multiple, intermittent, footshock stress (FS) sessions during 96h of REM sleep deprivation (REMSD) display increased REM sleep rebound (when compared to the only REMSD ones, without FS), which is correlated to high plasma prolactin levels. To investigate whether brain prolactin plays a role in stress-induced REM sleep rebound two experiments were carried out. In experiment 1, rats were either not sleep-deprived (NSD) or submitted to 96h of REMSD associated or not to FS and brains were evaluated for PRL immunoreactivity (PRL-ir) and determination of PRL concentrations in the lateral hypothalamus and dorsal raphe nucleus. In experiment 2, rats were implanted with cannulas in the dorsal raphe nucleus for prolactin infusion and were sleep-recorded. REMSD associated with FS increased PRL-ir and content in the lateral hypothalamus and all manipulations increased prolactin content in the dorsal raphe nucleus compared to the NSD group. Prolactin infusion in the dorsal raphe nucleus increased the time and length of REM sleep episodes 3h after the infusion until the end of the light phase of the day cycle. Based on these results we concluded that brain prolactin is a major mediator of stress-induced REMS. The effect of PRL infusion in the dorsal raphe nucleus is discussed in light of the existence of a bidirectional relationship between this hormone and serotonin as regulators of stress-induced REM sleep rebound.

  10. The reversibility error method (REM): a new, dynamical fast indicator for planetary dynamics

    NASA Astrophysics Data System (ADS)

    Panichi, Federico; Goździewski, Krzyszof; Turchetti, Giorgio

    2017-02-01

    We describe the reversibility error method (REM) and its applications to planetary dynamics. REM is based on the time-reversibility analysis of the phase-space trajectories of conservative Hamiltonian systems. The round-off errors break the time reversibility and the displacement from the initial condition, occurring when we integrate it forward and backward for the same time interval, is related to the dynamical character of the trajectory. If the motion is chaotic, in the sense of non-zero maximal Lyapunov characteristic exponent (mLCE), then REM increases exponentially with time, as exp λt, while when the motion is regular (quasi-periodic), then REM increases as a power law in time, as tα, where α and λ are real coefficients. We compare the REM with a variant of mLCE, the mean exponential growth factor of nearby orbits. The test set includes the restricted three-body problem and five resonant planetary systems: HD 37124, Kepler-60, Kepler-36, Kepler-29 and Kepler-26. We found a very good agreement between the outcomes of these algorithms. Moreover, the numerical implementation of REM is astonishing simple, and is based on solid theoretical background. The REM requires only a symplectic and time-reversible (symmetric) integrator of the equations of motion. This method is also CPU efficient. It may be particularly useful for the dynamical analysis of multiple planetary systems in the Kepler sample, characterized by low-eccentricity orbits and relatively weak mutual interactions. As an interesting side result, we found a possible stable chaos occurrence in the Kepler-29 planetary system.

  11. REM sleep loss associated changes in orexin-A levels in discrete brain areas in rats.

    PubMed

    Mehta, Rachna; Khanday, Mudasir Ahmad; Mallick, Birendra Nath

    2015-03-17

    Rapid eye movement sleep (REMS) serves house-keeping function of the brain and its loss affects several pathophysiological processes. Relative levels of neurotransmitters including orexin A (Orx-A) in various parts of the brain in health and diseases are among the key factors for modulation of behaviors, including REMS. The level of neurotransmitter in an area in the brain directly depends on number of projecting neurons and their firing rates. The locus coeruleus (LC), the site of REM-OFF neurons, receives densest, while the pedunculo-pontine area (PPT), the site of REM-ON neurons receives lesser projections from the Orx-ergic neurons. Further, the Orx-ergic neurons are active during waking and silent during REMS and NREMS. Therefore, the level of Orx-A in discrete regions of the brain is likely to be different during normal and altered states, which in turn is likely to be responsible for altered behaviors in health and diseases, including in relation to REMS. Therefore, in the present study, we estimated Orx-A level in LC, cortex, posterior hypothalamus (PH), hippocampus, and PPT after 96 h REMSD, in post-deprivation recovered rats and in control rats. This is the first report of estimation of Orx-A in different brain regions after prolonged REMSD. It was observed that after REMSD the Orx-A level increased significantly in LC, cortex and PH which returned to normal level after recovery; however, the level did not change in the hippocampus and PPT. The Orx-A induced modulation of REMS could be secondary to increased waking.

  12. Effects of age on recovery of body weight following REM sleep deprivation of rats.

    PubMed

    Koban, Michael; Stewart, Craig V

    2006-01-30

    Chronically enforced rapid eye (paradoxical) movement sleep deprivation (REM-SD) of rats leads to a host of pathologies, of which hyperphagia and loss of body weight are among the most readily observed. In recent years, the etiology of many REM-SD-associated pathologies have been elucidated, but one unexplored area is whether age affects outcomes. In this study, male Sprague-Dawley rats at 2, 6, and 12 months of age were REM sleep-deprived with the platform (flowerpot) method for 10-12 days. Two-month-old rats resided on 7-cm platforms, while 10-cm platforms were used for 6- and 12-month-old rats; rats on 15-cm platforms served as tank controls (TCs). Daily changes in food consumption (g/kg(0.67)) and body weight (g) during baseline, REM-SD or TCs, and post-experiment recovery in home cages were determined. Compared to TCs, REM-SD resulted in higher food intake and decreases in body weight. When returned to home cages, food intake rapidly declined to baseline levels. Of primary interest was that rates of body weight gain during recovery differed between the age groups. Two-month-old rats rapidly restored body weight to pre-REM-SD mass within 5 days; 6-month-old rats were extrapolated by linear regression to have taken about 10 days, and for 12-month-old rats, the estimate was about 35 days. The observation that restoration of body weight following its loss during REM-SD may be age-dependent is in general agreement with the literature on aging effects on how mammals respond to stress.

  13. Quantum speed meter based on dissipative coupling

    NASA Astrophysics Data System (ADS)

    Vyatchanin, Sergey P.; Matsko, Andrey B.

    2017-01-01

    We consider dissipative coupling Fabry-Perot cavity, i.e. its input mirror transmittance depends on position of probe mass. We show that dissipative coupling provide possibility to realize quantum speed meter by natural way, without additional setup for subtraction of position x(t) and delayed position x(t-τ). Quantum speed meter is a quantum non demolition (QND) meter which allow to overcome Standatd Quantum Limit — we show it for speed meter based on dissipative coupling.

  14. Embedded solution for a microwave moisture meter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, the conversion of a PC or laptop-controlled microwave moisture meter to a stand-alone meter hosting its own embedded system is discussed. The moisture meter is based on the free-space transmission measurement technique and uses low-intensity microwaves to measure the attenuation and p...

  15. 10 CFR 451.7 - Metering requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Metering requirements. 451.7 Section 451.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.7 Metering requirements... renewable energy facility must be measured by a standard metering device that— (a) Meets generally...

  16. 10 CFR 451.7 - Metering requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Metering requirements. 451.7 Section 451.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.7 Metering requirements... renewable energy facility must be measured by a standard metering device that— (a) Meets generally...

  17. 10 CFR 451.7 - Metering requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Metering requirements. 451.7 Section 451.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.7 Metering requirements... renewable energy facility must be measured by a standard metering device that— (a) Meets generally...

  18. 10 CFR 451.7 - Metering requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Metering requirements. 451.7 Section 451.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.7 Metering requirements... renewable energy facility must be measured by a standard metering device that— (a) Meets generally...

  19. 10 CFR 451.7 - Metering requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Metering requirements. 451.7 Section 451.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION RENEWABLE ENERGY PRODUCTION INCENTIVES § 451.7 Metering requirements... renewable energy facility must be measured by a standard metering device that— (a) Meets generally...

  20. EXPERIENCE MONITORING FOR LOW LEVEL NEUTRON RADIATION AT THE H-CANYON AT THE SAVANNAH RIVER SITE

    SciTech Connect

    HOGUE, MARK

    2005-10-07

    Department of Energy contractors are required to monitor external occupational radiation exposure of an individual likely to receive an effective dose equivalent to the whole body of 0.1 rem (0.001sievert) or more in a year. For a working year of 2000 hours, this translates to a dose rate of 0.05 mrem/hr (0.5 {micro}Sv/hr). This can be a challenging requirement for neutron exposure because traditional surveys with shielded BF{sub 3} proportional counters are difficult to conduct, particularly at low dose rates. A modified survey method was used at the Savannah River Site to find low dose rates in excess of 0.05 mrem/hr. An unshielded He{sup 3} detector was used to find elevated gross slow neutron counts. Areas with high count rates on the unshielded He{sup 3} detector were further investigated with shielded BF{sub 3} proportional counters and thermoluminescent neutron dosimeters were placed in the area of interest. An office area was investigated with this method. The data initially suggested that whole body neutron dose rates to office workers could be occurring at levels significantly higher than 0.1 rem (0.001sievert). The final evaluation, however, showed that the office workers were exposed to less than 0.1 rem/yr (0.001sievert/yr) of neutron radiation.

  1. Characterization of extended range Bonner Sphere Spectrometers in the CERF high-energy broad neutron field at CERN

    NASA Astrophysics Data System (ADS)

    Agosteo, S.; Bedogni, R.; Caresana, M.; Charitonidis, N.; Chiti, M.; Esposito, A.; Ferrarini, M.; Severino, C.; Silari, M.

    2012-12-01

    The accurate determination of the ambient dose equivalent in the mixed neutron-photon fields encountered around high-energy particle accelerators still represents a challenging task. The main complexity arises from the extreme variability of the neutron energy, which spans over 10 orders of magnitude or more. Operational survey instruments, which response function attempts to mimic the fluence-to-ambient dose equivalent conversion coefficient up to GeV neutrons, are available on the market, but their response is not fully reliable over the entire energy range. Extended range rem counters (ERRC) do not require the exact knowledge of the energy distribution of the neutron field and the calibration can be done with a source spectrum. If the actual neutron field has an energy distribution different from the calibration spectrum, the measurement is affected by an added uncertainty related to the partial overlap of the fluence-to-ambient dose equivalent conversion curve and the response function. For this reason their operational use should always be preceded by an "in-field" calibration, i.e. a calibration made against a reference instrument exposed in the same field where the survey-meter will be employed. In practice the extended-range Bonner Sphere Spectrometer (ERBSS) is the only device which can serve as reference instrument in these fields, because of its wide energy range and the possibility to assess the neutron fluence and the ambient dose equivalent (H*(10)) values with the appropriate accuracy. Nevertheless, the experience gained by a number of experimental groups suggests that mandatory conditions for obtaining accurate results in workplaces are: (1) the use of a well-established response matrix, thus implying validation campaigns in reference monochromatic neutrons fields, (2) the expert and critical use of suitable unfolding codes, and (3) the performance test of the whole system (experimental set-up, elaboration and unfolding procedures) in a well

  2. Opposite Impact of REM Sleep on Neurobehavioral Functioning in Children with Common Psychiatric Disorders Compared to Typically Developing Children

    PubMed Central

    Kirov, Roumen; Brand, Serge; Banaschewski, Tobias; Rothenberger, Aribert

    2017-01-01

    Rapid eye movement (REM) sleep has been shown to be related to many adaptive cognitive and behavioral functions. However, its precise functions are still elusive, particularly in developmental psychiatric disorders. The present study aims at investigating associations between polysomnographic (PSG) REM sleep measurements and neurobehavioral functions in children with common developmental psychiatric conditions compared to typically developing children (TDC). Twenty-four children with attention-deficit/hyperactivity disorder (ADHD), 21 with Tourette syndrome/tic disorder (TD), 21 with ADHD/TD comorbidity, and 22 TDC, matched for age and gender, underwent a two-night PSG, and their psychopathological scores and intelligence quotient (IQ) were assessed. Major PSG findings showed more REM sleep and shorter REM latency in the children with psychiatric disorders than in the TDC. Multiple regression analyses revealed that in groups with developmental psychopathology, REM sleep proportion correlated positively with scores of inattention and negatively with performance IQ. In contrast, in the group of TDC, REM sleep proportion correlated negatively with scores of inattention and positively with performance IQ. Whilst shorter REM latency was associated with greater inattention scores in children with psychopathology, no such an association existed in the group of TDC. Altogether, these results indicate an opposite impact of REM sleep on neurobehavioral functioning, related to presence or absence of developmental psychiatric disorders. Our findings suggest that during development, REM sleep functions may interact dissimilarly with different pathways of brain maturation. PMID:28119653

  3. Effects of biperiden on sleep at baseline and after 72 h of REM sleep deprivation in the cat.

    PubMed

    Salin-Pascual, R J; Jimenez-Anguiano, A; Granados-Fuentes, D; Drucker-Colin, R

    1992-01-01

    We examined the effects of the muscarinic M1 antagonist biperiden in cats. In the first experiment a dose-response analysis was performed with intraventricular injection (IV ventricle) of biperiden. In the second experiment after REM sleep deprivation cats were injected with either biperiden (0.1 mg/kg) or saline. Biperiden produced a reduction in REM sleep percentage and an increase in REM sleep latency with these high doses. The 0.1 mg/kg biperiden dose, which did not suppress REM sleep at baseline, did reduce the REM sleep rebound. The present study suggests a modulatory role of biperiden on REM sleep regulatory processes. The fact that an effect of biperiden is noted only at the high doses suggests that at these doses the drug is influencing non-M1 receptors. Changes in the sensitivity of these receptors as a result of REM sleep deprivation might explain why a dose of biperiden will reduce REM sleep rebound, while being ineffective in suppressing REM sleep at baseline.

  4. Senior Vipassana Meditation practitioners exhibit distinct REM sleep organization from that of novice meditators and healthy controls.

    PubMed

    Maruthai, Nirmala; Nagendra, Ravindra P; Sasidharan, Arun; Srikumar, Sulekha; Datta, Karuna; Uchida, Sunao; Kutty, Bindu M

    2016-06-01

    Abstract/Summary The present study is aimed to ascertain whether differences in meditation proficiency alter rapid eye movement sleep (REM sleep) as well as the overall sleep-organization. Whole-night polysomnography was carried out using 32-channel digital EEG system. 20 senior Vipassana meditators, 16 novice Vipassana meditators and 19 non-meditating control subjects participated in the study. The REM sleep characteristics were analyzed from the sleep-architecture of participants with a sleep efficiency index >85%. Senior meditators showed distinct changes in sleep-organization due to enhanced slow wave sleep and REM sleep, reduced number of intermittent awakenings and reduced duration of non-REM stage 2 sleep. The REM sleep-organization was significantly different in senior meditators with more number of REM episodes and increased duration of each episode, distinct changes in rapid eye movement activity (REMA) dynamics due to increased phasic and tonic activity and enhanced burst events (sharp and slow bursts) during the second and fourth REM episodes. No significant differences in REM sleep organization was observed between novice and control groups. Changes in REM sleep-organization among the senior practitioners of meditation could be attributed to the intense brain plasticity events associated with intense meditative practices on brain functions.

  5. Opposite Impact of REM Sleep on Neurobehavioral Functioning in Children with Common Psychiatric Disorders Compared to Typically Developing Children.

    PubMed

    Kirov, Roumen; Brand, Serge; Banaschewski, Tobias; Rothenberger, Aribert

    2016-01-01

    Rapid eye movement (REM) sleep has been shown to be related to many adaptive cognitive and behavioral functions. However, its precise functions are still elusive, particularly in developmental psychiatric disorders. The present study aims at investigating associations between polysomnographic (PSG) REM sleep measurements and neurobehavioral functions in children with common developmental psychiatric conditions compared to typically developing children (TDC). Twenty-four children with attention-deficit/hyperactivity disorder (ADHD), 21 with Tourette syndrome/tic disorder (TD), 21 with ADHD/TD comorbidity, and 22 TDC, matched for age and gender, underwent a two-night PSG, and their psychopathological scores and intelligence quotient (IQ) were assessed. Major PSG findings showed more REM sleep and shorter REM latency in the children with psychiatric disorders than in the TDC. Multiple regression analyses revealed that in groups with developmental psychopathology, REM sleep proportion correlated positively with scores of inattention and negatively with performance IQ. In contrast, in the group of TDC, REM sleep proportion correlated negatively with scores of inattention and positively with performance IQ. Whilst shorter REM latency was associated with greater inattention scores in children with psychopathology, no such an association existed in the group of TDC. Altogether, these results indicate an opposite impact of REM sleep on neurobehavioral functioning, related to presence or absence of developmental psychiatric disorders. Our findings suggest that during development, REM sleep functions may interact dissimilarly with different pathways of brain maturation.

  6. NEUTRON SOURCE

    DOEpatents

    Bernander, N.K. et al.

    1960-10-18

    An apparatus is described for producing neutrons through target bombardment with deuterons. Deuterium gas is ionized by electron bombardment and the deuteron ions are accelerated through a magnetic field to collimate them into a continuous high intensity beam. The ion beam is directed against a deuteron pervious metal target of substantially the same nnaterial throughout to embed the deuterous therein and react them to produce neutrons. A large quantity of neutrons is produced in this manner due to the increased energy and quantity of ions bombarding the target.

  7. Thermal neutron detection system

    DOEpatents

    Peurrung, Anthony J.; Stromswold, David C.

    2000-01-01

    According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

  8. Neutron shielding material based on colemanite and epoxy resin.

    PubMed

    Okuno, Koichi

    2005-01-01

    In recent years, there has been a need for compact shielding design such as self-shielding of a PET cyclotron or upgradation of radiation machinery in existing facilities. In these cases, high performance shielding materials are needed. Concrete or polyethylene have been used for a neutron shield. However, for compact shielding, they fall short in terms of performance or durability. Therefore, a new type of neutron shielding material based on epoxy resin and colemanite has been developed. Slab attenuation experiments up to 40 cm for the new shielding material were carried out using a 252Cf neutron source. Measurement was carried out using a REM-counter, and compared with calculation. The results show that the shielding performance is better than concrete and polyethylene mixed with 10 wt% boron oxide. From the result, we confirmed that the performance of the new material is suitable for practical use.

  9. Sleep disturbances in Parkinson's disease: the contribution of dopamine in REM sleep regulation.

    PubMed

    Lima, Marcelo M S

    2013-10-01

    Nearly all patients with Parkinson's disease (PD) have sleep disturbances. While it has been suggested that these disturbances involve a dopaminergic component, the specific mechanisms that contribute to this behavior are far from being fully understood. In this article, we have reviewed the current understanding of the linkage between sleep and PD, focusing on the participation of the dopaminergic system in the regulation of rapid eye movement (REM) sleep. The presence of an REM sleep behavior disorder in patients with PD might reflect the early involvement of dopaminergic neurotransmission in REM sleep-related structures. Therefore, it has been suggested that these structures are affected by an imbalance of dopamine levels. Several studies have demonstrated that neurons in the substantia nigra pars compacta (SNpc) and in the ventral tegmental area (VTA) are active during REM sleep and that sleep-related disturbances may result when these neurons are targeted by neurotoxins. We discuss current evidence suggesting the presence of a putative reciprocal connectivity between the SNpc, VTA, the pedunculopontine tegmental nucleus and reticular formation, which may exert an important influence on the REM sleep mechanism. This review provides a comprehensive overview of the literature that addresses this challenging and unrecognized component of PD.

  10. Local Slow Waves in Superficial Layers of Primary Cortical Areas during REM Sleep.

    PubMed

    Funk, Chadd M; Honjoh, Sakiko; Rodriguez, Alexander V; Cirelli, Chiara; Tononi, Giulio

    2016-02-08

    Sleep is traditionally constituted of two global behavioral states, non-rapid eye movement (NREM) and rapid eye movement (REM), characterized by quiescence and reduced responsiveness to sensory stimuli [1]. NREM sleep is distinguished by slow waves and spindles throughout the cerebral cortex and REM sleep by an "activated," low-voltage fast electroencephalogram (EEG) paradoxically similar to that of wake, accompanied by rapid eye movements and muscle atonia. However, recent evidence has shown that cortical activity patterns during wake and NREM sleep are not as global as previously thought. Local slow waves can appear in various cortical regions in both awake humans [2] and rodents [3-5]. Intracranial recordings in humans [6] and rodents [4, 7] have shown that NREM sleep slow waves most often involve only a subset of brain regions that varies from wave to wave rather than occurring near synchronously across all cortical areas. Moreover, some cortical areas can transiently "wake up" [8] in an otherwise sleeping brain. Yet until now, cortical activity during REM sleep was thought to be homogenously wake-like. We show here, using local laminar recordings in freely moving mice, that slow waves occur regularly during REM sleep, but only in primary sensory and motor areas and mostly in layer 4, the main target of relay thalamic inputs, and layer 3. This finding may help explain why, during REM sleep, we remain disconnected from the environment even though the bulk of the cortex shows wake-like, paradoxical activation.

  11. Visual short-term memory deficits in REM sleep behaviour disorder mirror those in Parkinson's disease.

    PubMed

    Rolinski, Michal; Zokaei, Nahid; Baig, Fahd; Giehl, Kathrin; Quinnell, Timothy; Zaiwalla, Zenobia; Mackay, Clare E; Husain, Masud; Hu, Michele T M

    2016-01-01

    Individuals with REM sleep behaviour disorder are at significantly higher risk of developing Parkinson's disease. Here we examined visual short-term memory deficits--long associated with Parkinson's disease--in patients with REM sleep behaviour disorder without Parkinson's disease using a novel task that measures recall precision. Visual short-term memory for sequentially presented coloured bars of different orientation was assessed in 21 patients with polysomnography-proven idiopathic REM sleep behaviour disorder, 26 cases with early Parkinson's disease and 26 healthy controls. Three tasks using the same stimuli controlled for attentional filtering ability, sensorimotor and temporal decay factors. Both patients with REM sleep behaviour disorder and Parkinson's disease demonstrated a deficit in visual short-term memory, with recall precision significantly worse than in healthy controls with no deficit observed in any of the control tasks. Importantly, the pattern of memory deficit in both patient groups was specifically explained by an increase in random responses. These results demonstrate that it is possible to detect the signature of memory impairment associated with Parkinson's disease in individuals with REM sleep behaviour disorder, a condition associated with a high risk of developing Parkinson's disease. The pattern of visual short-term memory deficit potentially provides a cognitive marker of 'prodromal' Parkinson's disease that might be useful in tracking disease progression and for disease-modifying intervention trials.

  12. REM Sleep, Prefrontal Theta, and the Consolidation of Human Emotional Memory

    PubMed Central

    Nishida, Masaki; Pearsall, Jori; Buckner, Randy L.

    2009-01-01

    Both emotion and sleep are independently known to modulate declarative memory. Memory can be facilitated by emotion, leading to enhanced consolidation across increasing time delays. Sleep also facilitates offline memory processing, resulting in superior recall the next day. Here we explore whether rapid eye movement (REM) sleep, and aspects of its unique neurophysiology, underlie these convergent influences on memory. Using a nap paradigm, we measured the consolidation of neutral and negative emotional memories, and the association with REM-sleep electrophysiology. Subjects that napped showed a consolidation benefit for emotional but not neutral memories. The No-Nap control group showed no evidence of a consolidation benefit for either memory type. Within the Nap group, the extent of emotional memory facilitation was significantly correlated with the amount of REM sleep and also with right-dominant prefrontal theta power during REM. Together, these data support the role of REM-sleep neurobiology in the consolidation of emotional human memories, findings that have direct translational implications for affective psychiatric and mood disorders. PMID:18832332

  13. Astrocytic IP3/Ca2+ Signaling Modulates Theta Rhythm and REM Sleep

    PubMed Central

    Foley, Jeannine; Blutstein, Tamara; Lee, SoYoung; Erneux, Christophe; Halassa, Michael M.; Haydon, Philip

    2017-01-01

    Rapid eye movement (REM) sleep onset is triggered by disinhibition of cholinergic neurons in the pons. During REM sleep, the brain exhibits prominent activity in the 5–8 Hz (theta) frequency range. How REM sleep onset and theta waves are regulated is poorly understood. Astrocytes, a non-neuronal cell type in the brain, respond to cholinergic signals by elevating their intracellular Ca2+ concentration. The goal of this study was to assess the sleep architecture of mice with attenuated IP3 mediated Ca2+ signaling in astrocytes. Vigilance states and cortical electroencephalograph power were measured in wild type mice and mice with attenuated IP3/Ca2+ signaling. Attenuating IP3/Ca2+ signaling specifically in astrocytes caused mice to spend more time in REM sleep and enter this state more frequently during their inactive phase. These mice also exhibited greater power in the theta frequency range. These data suggest a role for astrocytic IP3/Ca2+ signaling in modulating REM sleep and the associated physiological state of the cortex. PMID:28167901

  14. Orexin 2 Receptor Antagonism is Sufficient to Promote NREM and REM Sleep from Mouse to Man

    PubMed Central

    Gotter, Anthony L.; Forman, Mark S.; Harrell, Charles M.; Stevens, Joanne; Svetnik, Vladimir; Yee, Ka Lai; Li, Xiaodong; Roecker, Anthony J.; Fox, Steven V.; Tannenbaum, Pamela L.; Garson, Susan L.; Lepeleire, Inge De; Calder, Nicole; Rosen, Laura; Struyk, Arie; Coleman, Paul J.; Herring, W. Joseph; Renger, John J.; Winrow, Christopher J.

    2016-01-01

    Orexin neuropeptides regulate sleep/wake through orexin receptors (OX1R, OX2R); OX2R is the predominant mediator of arousal promotion. The potential for single OX2R antagonism to effectively promote sleep has yet to be demonstrated in humans. MK-1064 is an OX2R-single antagonist. Preclinically, MK-1064 promotes sleep and increases both rapid eye movement (REM) and non-REM (NREM) sleep in rats at OX2R occupancies higher than the range observed for dual orexin receptor antagonists. Similar to dual antagonists, MK-1064 increases NREM and REM sleep in dogs without inducing cataplexy. Two Phase I studies in healthy human subjects evaluated safety, tolerability, pharmacokinetics and sleep-promoting effects of MK-1064, and demonstrated dose-dependent increases in subjective somnolence (via Karolinska Sleepiness Scale and Visual Analogue Scale measures) and sleep (via polysomnography), including increased REM and NREM sleep. Thus, selective OX2R antagonism is sufficient to promote REM and NREM sleep across species, similarly to that seen with dual orexin receptor antagonism. PMID:27256922

  15. Hallucinations and REM sleep behaviour disorder in Parkinson's disease: dream imagery intrusions and other hypotheses.

    PubMed

    Manni, Raffaele; Terzaghi, Michele; Ratti, Pietro-Luca; Repetto, Alessandra; Zangaglia, Roberta; Pacchetti, Claudio

    2011-12-01

    REM sleep behaviour disorder (RBD) is a REM sleep-related parasomnia which may be considered a "dissociated state of wakefulness and sleep", given that conflicting elements of REM sleep (dreaming) and of wakefulness (sustained muscle tone and movements) coexist during the episodes, leading to motor and behavioural manifestations reminiscent of an enacted dream. RBD has been reported in association with α-synucleinopathies: around a third of patients with Parkinson's disease (PD) have full-blown RBD. Recent data indicate that PD patients with RBD are more prone to hallucinations than PD patients without this parasomnia. However it is still not clear why RBD in PD is associated with an increased prevalence of VHs. Data exist which suggest that visual hallucinations in PD may be the result of untimely intrusions of REM visual imagery into wakefulness. RBD, which is characterised by a REM sleep dissociation pattern, might be a condition that particularly favours such intrusions. However, other hypotheses may be advanced. In fact, deficits in attentional, executive, visuoperceptual and visuospatial abilities have been documented in RBD and found to occur far more frequently in PD with RBD than in PD without RBD. Neuropsychological deficits involving visual perception and attentional processes are thought to play an important role in the pathophysiology of VHs. On this basis, RBD in PD could be viewed as a contributory risk factor for VHs.

  16. Story-like organization of REM-dreams in patients with narcolepsy-cataplexy.

    PubMed

    Cipolli, Carlo; Bellucci, Claudia; Mattarozzi, Katia; Mazzetti, Michela; Tuozzi, Giovanni; Plazzi, Giuseppe

    2008-10-22

    Narcolepsy with cataplexy (NC) is a neurological disorder characterized by excessive daytime sleepiness and an altered architecture of sleep. Previous laboratory studies have shown that frightening, bizarre and visually vivid contents are more frequent in dream experiences developed during the first period of REM sleep by NC patients than healthy subjects. As the structural organization of dream experiences of NC patients has not been yet examined, we compared its indicators in dream reports collected from a sample of NC patients and their matched controls. During an experimental night two awakenings were provoked after 8min of REM sleep in the first and third sleep cycle. Dream reports were analyzed using the rules of story grammars, capable of identifying units larger than single contents and describing their story-like organization. While dream recall (about 85%) was comparable in NC patients and controls, 1st-REM dream reports were longer in NC patients. Statistical analyses on the 12 NC patients and their matched controls who reported dreams after both REM periods showed that dream experiences occurring in 1st-REM reports of NC patients were longer and had a more complex organization than those of controls. These findings suggest that the cognitive processes underlying dream generation reach their optimal functioning earlier in the night in NC patients than in normal subjects.

  17. Idiopathic REM sleep behaviour disorder in the development of Parkinson's disease.

    PubMed

    Boeve, Bradley F

    2013-05-01

    Parkinson's disease is a progressive neurodegenerative disorder associated with Lewy body disease pathology in central and peripheral nervous system structures. Although the cause of Parkinson's disease is not fully understood, clinicopathological analyses have led to the development of a staging system for Lewy body disease-associated pathological changes. This system posits a predictable topography of progression of Lewy body disease in the CNS, beginning in olfactory structures and the medulla, then progressing rostrally from the medulla to the pons, then to midbrain and substantia nigra, limbic structures, and neocortical structures. If this topography and temporal evolution of Lewy body disease does occur, other manifestations of the disease as a result of degeneration of olfactory and pontomedullary structures could theoretically begin many years before the development of prominent nigral degeneration and the associated parkinsonian features of Parkinson's disease. One such manifestation of prodromal Parkinson's disease is rapid eye movement (REM) sleep behaviour disorder, which is a parasomnia manifested by vivid dreams associated with dream enactment behaviour during REM sleep. Findings from animal and human studies have suggested that lesions or dysfunction in REM sleep and motor control circuitry in the pontomedullary structures cause REM sleep behaviour disorder phenomenology, and degeneration of these structures might explain the presence of REM sleep behaviour disorder years or decades before the onset of parkinsonism in people who develop Parkinson's disease.

  18. Coherent neocortical gamma oscillations decrease during REM sleep in the rat.

    PubMed

    Cavelli, Matías; Castro, Santiago; Schwarzkopf, Natalia; Chase, Michael H; Falconi, Atilio; Torterolo, Pablo

    2015-03-15

    Higher cognitive functions require the integration and coordination of large populations of neurons in cortical and subcortical regions. Oscillations in the high frequency band (30-100 Hz) of the electroencephalogram (EEG), that have been postulated to be a product of this interaction, are involved in the binding of spatially separated but temporally correlated neural events, which results in a unified perceptual experience. The extent of this functional connectivity can be examined by means of the mathematical algorithm called "coherence", which is correlated with the "strength" of functional interactions between cortical areas. As a continuation of previous studies in the cat [6,7], the present study was conducted to analyze EEG coherence in the gamma band of the rat during wakefulness (W), non-REM (NREM) sleep and REM sleep. Rats were implanted with electrodes in different cortical areas to record EEG activity, and the magnitude squared coherence values within the gamma frequency band of EEG (30-48 and 52-100 Hz) were determined. Coherence between all cortical regions in the low and high gamma frequency bands was greater during W compared with sleep. Remarkably, EEG coherence in the low and high gamma bands was smallest during REM sleep. We conclude that high frequency interactions between cortical areas are radically different during sleep and wakefulness in the rat. Since this feature is conserved in other mammals, including humans, we suggest that the uncoupling of gamma frequency activity during REM sleep is a defining trait of REM sleep in mammals.

  19. Astrocytic IP3/Ca(2+) Signaling Modulates Theta Rhythm and REM Sleep.

    PubMed

    Foley, Jeannine; Blutstein, Tamara; Lee, SoYoung; Erneux, Christophe; Halassa, Michael M; Haydon, Philip

    2017-01-01

    Rapid eye movement (REM) sleep onset is triggered by disinhibition of cholinergic neurons in the pons. During REM sleep, the brain exhibits prominent activity in the 5-8 Hz (theta) frequency range. How REM sleep onset and theta waves are regulated is poorly understood. Astrocytes, a non-neuronal cell type in the brain, respond to cholinergic signals by elevating their intracellular Ca(2+) concentration. The goal of this study was to assess the sleep architecture of mice with attenuated IP3 mediated Ca(2+) signaling in astrocytes. Vigilance states and cortical electroencephalograph power were measured in wild type mice and mice with attenuated IP3/Ca(2+) signaling. Attenuating IP3/Ca(2+) signaling specifically in astrocytes caused mice to spend more time in REM sleep and enter this state more frequently during their inactive phase. These mice also exhibited greater power in the theta frequency range. These data suggest a role for astrocytic IP3/Ca(2+) signaling in modulating REM sleep and the associated physiological state of the cortex.

  20. NEUTRONIC REACTOR

    DOEpatents

    Wade, E.J.

    1958-09-16

    This patent relates to a reflector means for a neutronic reactor. A reflector comprised of a plurality of vertically movable beryllium control members is provided surrounding the sides of the reactor core. An absorber of fast neutrons comprised of natural uramum surrounds the reflector. An absorber of slow neutrons surrounds the absorber of fast neutrons and is formed of a plurality of beryllium blocks having natural uranium members distributcd therethrough. in addition, a movable body is positioned directly below the core and is comprised of a beryllium reflector and an absorbing member attached to the botiom thereof, the absorbing member containing a substance selected from the goup consisting of natural urantum and Th/sup 232/.

  1. Neutron reflectivity

    NASA Astrophysics Data System (ADS)

    Cousin, Fabrice; Menelle, Alain

    2015-10-01

    The specular neutron reflectivity is a technique enabling the measurement of neutron scattering length density profile perpendicular to the plane of a surface or an interface, and thereby the profile of chemical composition. The characteristic sizes that are probed range from around 5 Å up 5000 Å. It is a scattering technique that averages information on the entire surface and it is therefore not possible to obtain information within the plane of the interface. The specific properties of neutrons (possibility of tuning the contrast by isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons) makes it particularly interesting in the fields of soft matter, biophysics and magnetic thin films. This course is a basic introduction to the technique and does not address the magnetic reflectivity. It is composed of three parts describing respectively its principle and its formalism, the experimental aspects of the method (spectrometers, samples) and two examples related to the materials for energy.

  2. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.

    1960-11-22

    A nuclear reactor is described wherein horizontal rods of thermal- neutron-fissionable material are disposed in a body of heavy water and extend through and are supported by spaced parallel walls of graphite.

  3. NEUTRON SOURCES

    DOEpatents

    Richmond, J.L.; Wells, C.E.

    1963-01-15

    A neutron source is obtained without employing any separate beryllia receptacle, as was formerly required. The new method is safer and faster, and affords a source with both improved yield and symmetry of neutron emission. A Be container is used to hold and react with Pu. This container has a thin isolating layer that does not obstruct the desired Pu--Be reaction and obviates procedures previously employed to disassemble and remove a beryllia receptacle. (AEC)

  4. NEUTRONIC REACTOR

    DOEpatents

    Fraas, A.P.; Mills, C.B.

    1961-11-21

    A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

  5. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.

    1958-04-22

    A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

  6. Discussion series on PURPA related topics: metering

    SciTech Connect

    Sturgeon, J I

    1980-08-01

    Time-differentiated metering of electricity consumption and demand is required in both rate-structure experimentation and the implementation of most time-of-use rate designs. Time-differentiated metering takes three major forms: multi-register watthour meters, magnetic-tape recording meters, and remote automatic meter-reading systems. The majority of projects selected magnetic-tape meters for their flexibility with respect to rate structure, load-survey capabilities, and ready availability. The small-scale, experimental nature of the projects reduced the significance of the large difference in per-unit cost and operational/maintenance complexity between this form of metering and the multi-register form. Magnetic-tape meters are not likely candidates for system-wide implementation of time-differentiated metering. Automatic remote-meter-reading systems were not adequately available during the project years; those projects attempting to use these were unable to bring them to full operational status before project termination, due to the many problems of design, quality control, and equipment acquisition encountered. Delays in acquisition and problems of quality control also followed the selection of magnetic-tape meters and multi-register meters by a number of the projects. Though less complex than automatic remote-reading systems, these technologies are still new and more complex than standard watthour metering. Thus, both equipment vendors and utilities encountered numerous problems in getting properly functioning meters to the service entrances on time. A variety of factors contributed to installation delays, including unforeseen space limitations, incompatible wiring, problems of task organization, and customer reluctance.

  7. Development of a Bonner Sphere neutron spectrometer from a commercial neutron dosimeter

    NASA Astrophysics Data System (ADS)

    Chu, M. C.; Fung, K. Y.; Kwok, T.; Leung, J. K. C.; Lin, Y. C.; Liu, H.; Luk, K. B.; Ngai, H. Y.; Pun, C. S. J.; Wong, H. L. H.

    2016-11-01

    Bonner Spheres have been used widely for the measurement of neutron spectra with neutron energies ranged from thermal up to at least 20 MeV . A Bonner Sphere neutron spectrometer (BSS) was developed by extending a Berthold LB 6411 neutron-dose-rate meter. The BSS consists of a 3He thermal-neutron detector with integrated electronics, a set of eight polyethylene spherical shells and two optional lead shells of various sizes. The response matrix of the BSS was calculated with GEANT4 Monte Carlo simulation. The BSS had a calibration uncertainty of ± 8.6% and a detector background rate of (1.57 ± 0.04) × 10-3 s-1. A spectral unfolding code NSUGA was developed. The NSUGA code utilizes genetic algorithms and has been shown to perform well in the absence of a priori information.

  8. The homeostatic regulation of REM sleep: A role for localized expression of brain-derived neurotrophic factor in the brainstem.

    PubMed

    Datta, Subimal; Knapp, Clifford M; Koul-Tiwari, Richa; Barnes, Abigail

    2015-10-01

    Homeostatic regulation of REM sleep plays a key role in neural plasticity and deficits in this process are implicated in the development of many neuropsychiatric disorders. Little is known, however, about the molecular mechanisms that underlie this homeostatic regulation process. This study examined the hypothesis that, during selective REM sleep deprivation (RSD), increased brain-derived neurotrophic factor (BDNF) expression in REM sleep regulating areas is critical for the development of homeostatic drive for REM sleep, as measured by an increase in the number of REM sleep transitions. Rats were assigned to RSD, non-sleep deprived (BSL), or total sleep deprivation (TSD) groups. Physiological recordings were obtained from cortical, hippocampal, and pontine EEG electrodes over a 6h period, in which sleep deprivation occurred during the first 3h. In the RSD, but not the other conditions, homeostatic drive for REM sleep increased progressively. BDNF protein expression was significantly greater in the pedunculopontine tegmentum (PPT) and subcoeruleus nucleus (SubCD) in the RSD as compared to the TSD and BSL groups, areas that regulate REM sleep, but not in the medial preoptic area, which regulates non-REM sleep. There was a significant positive correlation between RSD-induced increases in number of REM sleep episodes and increased BDNF expression in the PPT and SubCD. These increases positively correlated with levels of homeostatic drive for REM sleep. These results, for the first time, suggest that selective RSD-induced increased expression of BDNF in the PPT and SubCD are determinant factors in the development of the homeostatic drive for REM sleep.

  9. FOREWORD: Neutron metrology Neutron metrology

    NASA Astrophysics Data System (ADS)

    Thomas, David J.; Nolte, Ralf; Gressier, Vincent

    2011-12-01

    The International Committee for Weights and Measures (CIPM) has consultative committees covering various areas of metrology. The Consultative Committee for Ionizing Radiation (CCRI) differs from the others in having three sections: Section (I) deals with radiation dosimetry, Section (II) with radionuclide metrology and Section (III) with neutron metrology. In 2003 a proposal was made to publish special issues of Metrologia covering the work of the three Sections. Section (II) was the first to complete their task, and their special issue was published in 2007, volume 44(4). This was followed in 2009 by the special issue on radiation dosimetry, volume 46(2). The present issue, volume 48(6), completes the trilogy and attempts to explain neutron metrology, the youngest of the three disciplines, the neutron only having been discovered in 1932, to a wider audience and to highlight the relevance and importance of this field. When originally approached with the idea of this special issue, Section (III) immediately saw the value of a publication specifically on neutron metrology. It is a topic area where papers tend to be scattered throughout the literature in journals covering, for example, nuclear instrumentation, radiation protection or radiation measurements in general. Review articles tend to be few. People new to the field often ask for an introduction to the various topics. There are some excellent older textbooks, but these are now becoming obsolete. More experienced workers in specific areas of neutron metrology can find it difficult to know the latest position in related areas. The papers in this issue attempt, without presenting a purely historical outline, to describe the field in a sufficiently logical way to provide the novice with a clear introduction, while being sufficiently up-to-date to provide the more experienced reader with the latest scientific developments in the different topic areas. Neutron radiation fields obviously occur throughout the nuclear

  10. Reassessment of NRC`s dollar per person-rem conversion factor policy

    SciTech Connect

    1995-12-01

    The US Nuclear Regulatory Commission (NRC) has completed a review and analysis of its dollar per person-rem conversion factor policy. As a result of this review, the NRC has decided to adopt a $2000 per person-rem conversion factor, subject it to present worth considerations, and limit its scope solely to health effects. This is in contrast to the previous policy and staff practice of using an undiscounted $1000 per person-rem conversion factor that served as a surrogate for all offsite consequences (health and offsite property). The policy shift has been incorporated in ``Regulatory Analysis Guidelines of the US Nuclear Regulatory Commission,`` NUREG/BR-0058, Revision 2, November 1995.

  11. Melatonin therapy for REM sleep behavior disorder: a critical review of evidence.

    PubMed

    McGrane, Ian R; Leung, Jonathan G; St Louis, Erik K; Boeve, Bradley F

    2015-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia associated with dream enactment often involving violent or potentially injurious behaviors during REM sleep that is strongly associated with synucleinopathy neurodegeneration. Clonazepam has long been suggested as the first-line treatment option for RBD. However, evidence supporting melatonin therapy is expanding. Melatonin appears to be beneficial for the management of RBD with reductions in clinical behavioral outcomes and decrease in muscle tonicity during REM sleep. Melatonin also has a favorable safety and tolerability profile over clonazepam with limited potential for drug-drug interactions, an important consideration especially in elderly individuals with RBD receiving polypharmacy. Prospective clinical trials are necessary to establish the evidence basis for melatonin and clonazepam as RBD therapies.

  12. Melatonin Therapy for REM Sleep Behavior Disorder: A Critical Review of Evidence

    PubMed Central

    Leung, Jonathan G.; St Louis, Erik K.; Boeve, Bradley F.

    2014-01-01

    REM sleep behavior disorder (RBD) is a parasomnia associated with dream enactment often involving violent or potentially injurious behaviors during REM sleep that is strongly associated with synucleinopathy neurodegeneration. Clonazepam has long been suggested as the first-line treatment option for RBD. However, evidence supporting melatonin therapy is expanding. Melatonin appears to be beneficial for the management of RBD with reductions in clinical behavioral outcomes and decrease in muscle tonicity during REM sleep. Melatonin also has a favorable safety and tolerability profile over clonazepam with limited potential for drug-drug interactions, an important consideration especially in elderly individuals with RBD receiving polypharmacy. Prospective clinical trials are necessary to establish evidence-basis for melatonin and clonazepam as RBD therapies. PMID:25454845

  13. Why Does Rem Sleep Occur? A Wake-Up Hypothesis1

    PubMed Central

    Klemm, W. R.

    2011-01-01

    Brain activity differs in the various sleep stages and in conscious wakefulness. Awakening from sleep requires restoration of the complex nerve impulse patterns in neuronal network assemblies necessary to re-create and sustain conscious wakefulness. Herein I propose that the brain uses rapid eye movement (REM) to help wake itself up after it has had a sufficient amount of sleep. Evidence suggesting this hypothesis includes the facts that, (1) when first going to sleep, the brain plunges into Stage N3 (formerly called Stage IV), a deep abyss of sleep, and, as the night progresses, the sleep is punctuated by episodes of REM that become longer and more frequent toward morning, (2) conscious-like dreams are a reliable component of the REM state in which the dreamer is an active mental observer or agent in the dream, (3) the last awakening during a night's sleep usually occurs in a REM episode during or at the end of a dream, (4) both REM and awake consciousness seem to arise out of a similar brainstem ascending arousal system (5) N3 is a functionally perturbed state that eventually must be corrected so that embodied brain can direct adaptive behavior, and (6) cortico-fugal projections to brainstem arousal areas provide a way to trigger increased cortical activity in REM to progressively raise the sleeping brain to the threshold required for wakefulness. This paper shows how the hypothesis conforms to common experience and has substantial predictive and explanatory power regarding the phenomenology of sleep in terms of ontogeny, aging, phylogeny, abnormal/disease states, cognition, and behavioral physiology. That broad range of consistency is not matched by competing theories, which are summarized herein. Specific ways to test this wake-up hypothesis are suggested. Such research could lead to a better understanding of awake consciousness. PMID:21922003

  14. REM and NREM sleep as natural accompaniments of the evolution of warm-bloodedness.

    PubMed

    Lee Kavanau, J

    2002-12-01

    Divergence of primitive sleep into REM and NREM states is thought to have occurred in the nocturnal Triassic ancestors of mammals as a natural accompaniment of the evolution of warm-bloodedness. As ambient temperatures during twilight portions of primitive sleep traversed these evolving ancestors' core temperature, mechanisms of thermoregulatory control that employ muscle contractions became superfluous. The resulting loss of need for such contractions during twilight sleep led to muscle atonia. With muscle tone absent, selection favored the persistence of the fast waves of nocturnal activity during twilight sleep. Stimulations by these waves reinforce motor circuits at the increasing temperatures of evolving warm-bloodedness without leading to sleep-disturbing muscle contractions. By these and related interlinked adaptations, twilight sleep evolved into REM sleep. The daytime period of sleep became NREM sleep. The evolution of NREM and REM sleep following this scenario has implications for sleep's maintenance processes for long-term memories. During NREM sleep, there is an unsynchronized, uncoordinated stimulation and reinforcement of individual distributed component circuits of consolidated memories by slow wave potentials, a process termed 'uncoordinated reinforcement'. The corresponding process during REM sleep is the coordinated stimulation and reinforcement of these circuits by fast wave potentials. This action temporally binds the individual component circuit outputs into fully formed memories, a process termed 'coordinated reinforcement'. Sequential uncoordinated and coordinated reinforcement, that is, NREM followed by REM sleep, emerges as the most effective mechanism of long-term memory maintenance in vertebrates. With the evolution of this two-stage mechanism of long-term memory maintenance, it became adaptive to partition sleep into several NREM-REM cycles, thereby achieving a more lengthy application of the cooperative sequential actions.

  15. Is a purpose of REM sleep atonia to help regenerate intervertebral disc volumetric loss?

    PubMed Central

    Fryer, Jerome CJ

    2009-01-01

    The nature of atonia in sleep continues to be enigmatic. This article discusses a new hypothesis for complete core muscle relaxation in REM sleep, suggesting a bottom-up recuperative perspective. That is, does the atonia in REM sleep provide a utility to help restore the mechanobiology and respective diurnal intervertebral disc hydraulic loss? By combining the effects of gravity with current compressive concepts in spinal stability, this article looks at vertebral approximation as a deleterious experience with an intrinsic biological need to keep vertebrae separated. Methods using polysomnography and recumbent MRI are discussed. PMID:19123938

  16. REM sleep and memory reorganization: Potential relevance for psychiatry and psychotherapy.

    PubMed

    Landmann, Nina; Kuhn, Marion; Maier, Jonathan-Gabriel; Spiegelhalder, Kai; Baglioni, Chiara; Frase, Lukas; Riemann, Dieter; Sterr, Annette; Nissen, Christoph

    2015-07-01

    Sleep can foster the reorganization of memory, i.e. the emergence of new memory content that has not directly been encoded. Current neurophysiological and behavioral evidence can be integrated into a model positing that REM sleep particularly promotes the disintegration of existing schemas and their recombination in the form of associative thinking, creativity and the shaping of emotional memory. Particularly, REM sleep related dreaming might represent a mentation correlate for the reconfiguration of memory. In a final section, the potential relevance for psychiatry and psychotherapy is discussed.

  17. Validation of the cuff pedestal technique for rapid eye movement sleep (REMs) deprivation by electrophysiological recordings.

    PubMed

    Hilakivi, I; Peder, M; Elomaa, E; Johansson, G

    1984-06-01

    Twenty-four-hour recordings of electrophysiological correlates of the sleep-waking cycle in the rat were performed during different stages of cuff pedestal treatment. It was found that rats adapted to live on pedestals with the cuff raised displayed undisturbed patterns of sleep and wakefulness. Lowering the cuff for three days resulted in virtually total disappearance of rapid eye movement sleep (REMs), while slow wave sleep (SWs) was only slightly reduced. Raising the cuff induced a prominent rebound increase of REMs. These results accord with data obtained by means of the conventional flowerpot procedure and corroborate the validity of the cuff pedestal technique.

  18. The effect of selective REM-sleep deprivation on the consolidation and affective evaluation of emotional memories.

    PubMed

    Wiesner, Christian D; Pulst, Julika; Krause, Fanny; Elsner, Marike; Baving, Lioba; Pedersen, Anya; Prehn-Kristensen, Alexander; Göder, Robert

    2015-07-01

    Emotion boosts the consolidation of events in the declarative memory system. Rapid eye movement (REM) sleep is believed to foster the memory consolidation of emotional events. On the other hand, REM sleep is assumed to reduce the emotional tone of the memory. Here, we investigated the effect of selective REM-sleep deprivation, SWS deprivation, or wake on the affective evaluation and consolidation of emotional and neutral pictures. Prior to an 9-h retention interval, sixty-two healthy participants (23.5 ± 2.5 years, 32 female, 30 male) learned and rated their affect to 80 neutral and 80 emotionally negative pictures. Despite rigorous deprivation of REM sleep or SWS, the residual sleep fostered the consolidation of neutral and negative pictures. Furthermore, emotional arousal helped to memorize the pictures. The better consolidation of negative pictures compared to neutral ones was most pronounced in the SWS-deprived group where a normal amount of REM sleep was present. This emotional memory bias correlated with REM sleep only in the SWS-deprived group. Furthermore, emotional arousal to the pictures decreased over time, but neither sleep nor wake had any differential effect. Neither the comparison of the affective ratings (arousal, valence) during encoding and recognition, nor the affective ratings of the recognized targets and rejected distractors supported the hypothesis that REM sleep dampens the emotional reaction to remembered stimuli. The data suggest that REM sleep fosters the consolidation of emotional memories but has no effect on the affective evaluation of the remembered contents.

  19. Affect Intensity and Phasic REM Sleep in Depressed Men before and after Treatment with Cognitive-Behavioral Therapy.

    ERIC Educational Resources Information Center

    Nofzinger, Eric A.; And Others

    1994-01-01

    Explored relationship between daytime affect and REM (rapid eye movement) sleep in 45 depressed men before and after treatment with cognitive-behavioral therapy and in control group of 43 healthy subjects. For depressed subjects only, intensity of daytime affect correlated significantly and positively with phasic REM sleep measures at pre- and…

  20. Replay of conditioned stimuli during late REM and stage N2 sleep influences affective tone rather than emotional memory strength.

    PubMed

    Rihm, Julia S; Rasch, Björn

    2015-07-01

    Emotional memories are reprocessed during sleep, and it is widely assumed that this reprocessing occurs mainly during rapid eye movement (REM) sleep. In support for this notion, vivid emotional dreams occur mainly during REM sleep, and several studies have reported emotional memory enhancement to be associated with REM sleep or REM sleep-related parameters. However, it is still unknown whether reactivation of emotional memories during REM sleep strengthens emotional memories. Here, we tested whether re-presentation of emotionally learned stimuli during REM sleep enhances emotional memory. In a split-night design, participants underwent Pavlovian conditioning after the first half of the night. Neutral sounds served as conditioned stimuli (CS) and were either paired with a negative odor (CS+) or an odorless vehicle (CS-). During sound replay in subsequent late REM or N2 sleep, half of the CS+ and half of the CS- were presented again. In contrast to our hypothesis, replay during sleep did not affect emotional memory as measured by the differentiation between CS+ and CS- in expectancy, arousal and valence ratings. However, replay unspecifically decreased subjective arousal ratings of both emotional and neutral sounds and increased positive valence ratings also for both CS+ and CS- sounds, respectively. These effects were slightly more pronounced for replay during REM sleep. Our results suggest that re-exposure to previously conditioned stimuli during late sleep does not affect emotional memory strength, but rather influences the affective tone of both emotional and neutral memories.

  1. A Change of Possible Neurological and Psychological Significance Within the First Week of Neonate Life: Sleeping REM Rate.

    ERIC Educational Resources Information Center

    Minard, James; And Others

    The percentage of rapid eye movement (REM) during sleep is substantially greater in neonates (infants in first month after birth) than in other children or adults. It was hypothesized that REM rate may decline as rates of many response sequences do when repeatedly elicited. Electrical recordings of eye movements were obtained from a 3-day-old male…

  2. The role of REM sleep in the processing of emotional memories: evidence from behavior and event-related potentials.

    PubMed

    Groch, S; Wilhelm, I; Diekelmann, S; Born, J

    2013-01-01

    Emotional memories are vividly remembered for the long-term. Rapid eye movement (REM) sleep has been repeatedly proposed to support the superior retention of emotional memories. However, its exact contribution and, specifically, whether its effect is mainly on the consolidation of the contents or the processing of the affective component of emotional memories is not clear. Here, we investigated the effects of sleep rich in slow wave sleep (SWS) or REM sleep on the consolidation of emotional pictures and the accompanying changes in affective tone, using event-related potentials (ERPs) together with subjective ratings of valence and arousal. Sixteen healthy, young men learned 50 negative and 50 neutral pictures before 3-h retention sleep intervals that were filled with either SWS-rich early or REM sleep-rich late nocturnal sleep. In accordance with our hypothesis, recognition was better for emotional pictures than neutral pictures after REM compared to SWS-rich sleep. This emotional enhancement after REM-rich sleep expressed itself in an increased late positive potential of the ERP over the frontal cortex 300-500 ms after stimulus onset for correctly classified old emotional pictures compared with new emotional and neutral pictures. Valence and arousal ratings of emotional pictures were not differentially affected by REM or SWS-rich sleep after learning. Our results corroborate that REM sleep contributes to the consolidation of emotional contents in memory, but suggest that the affective tone is preserved rather than reduced by the processing of emotional memories during REM sleep.

  3. The H1 histamine receptor blocker, chlorpheniramine, completely prevents the increase in REM sleep induced by immobilization stress in rats.

    PubMed

    Rojas-Zamorano, J A; Esqueda-Leon, E; Jimenez-Anguiano, A; Cintra-McGlone, L; Mendoza Melendez, M A; Velazquez Moctezuma, J

    2009-01-01

    Chlorpheniramine is a selective antagonist of the H1 histaminergic receptor subtype and its effects in humans include somnolence. Chlorpheniramine affects sleep in rats, mainly by decreasing REM sleep. On the other hand, stress by immobilization induces an important increase in the percentage of REM sleep. In this study we analyzed the effects of blocking histaminergic receptors on REM sleep induced by immobilization stress. Adult male Wistar rats were chronically implanted for sleep recording. Immobilization stress was induced by placing the rat in a small cylinder for 2 h. Experimental conditions were: A. Control; B. Stress; C. Stress plus vehicle and D. Stress plus chlorpheniramine. Independent experiments were done both in the dark, as well as the light period. Results showed that the increase in REM sleep observed after immobilization stress was completely abolished by chlorpheniramine, both in the dark and in the light phase. Furthermore, the decrease in REM sleep was significant even when compared to the non-stressed control rats. REM sleep latency was also significantly longer during both light phases. The present results suggest that REM sleep is quite sensitive to histaminergic blockage. It is possible that chlorpheniramine is also blocking the cholinergic mechanisms generating REM sleep.

  4. Quantitative differences among EMG activities of muscles innervated by subpopulations of hypoglossal and upper spinal motoneurons during non-REM sleep - REM sleep transitions: a window on neural processes in the sleeping brain.

    PubMed

    Rukhadze, I; Kamani, H; Kubin, L

    2011-12-01

    In the rat, a species widely used to study the neural mechanisms of sleep and motor control, lingual electromyographic activity (EMG) is minimal during non-rapid eye movement (non-REM) sleep and then phasic twitches gradually increase after the onset of REM sleep. To better characterize the central neural processes underlying this pattern, we quantified EMG of muscles innervated by distinct subpopulations of hypoglossal motoneurons and nuchal (N) EMG during transitions from non-REM sleep to REM sleep. In 8 chronically instrumented rats, we recorded cortical EEG, EMG at sites near the base of the tongue where genioglossal and intrinsic muscle fibers predominate (GG-I), EMG of the geniohyoid (GH) muscle, and N EMG. Sleep-wake states were identified and EMGs quantified relative to their mean levels in wakefulness in successive 10 s epochs. During non-REM sleep, the average EMG levels differed among the three muscles, with the order being N>GH>GG-I. During REM sleep, due to different magnitudes of phasic twitches, the order was reversed to GG-I>GH>N. GG-I and GH exhibited a gradual increase of twitching that peaked at 70-120 s after the onset of REM sleep and then declined if the REM sleep episode lasted longer. We propose that a common phasic excitatory generator impinges on motoneuron pools that innervate different muscles, but twitching magnitudes are different due to different levels of tonic motoneuronal hyperpolarization. We also propose that REM sleep episodes of average durations are terminated by intense activity of the central generator of phasic events, whereas long REM sleep episodes end as a result of a gradual waning of the tonic disfacilitatory and inhibitory processes.

  5. Neutron therapy of cancer

    NASA Technical Reports Server (NTRS)

    Frigerio, N. A.; Nellans, H. N.; Shaw, M. J.

    1969-01-01

    Reports relate applications of neutrons to the problem of cancer therapy. The biochemical and biophysical aspects of fast-neutron therapy, neutron-capture and neutron-conversion therapy with intermediate-range neutrons are presented. Also included is a computer program for neutron-gamma radiobiology.

  6. Multipath ultrasonic flow meters for gas measurement

    SciTech Connect

    Saunders, M.P.

    1995-11-01

    This paper gives an introduction to the practical application of ultrasonic gas flow meters. A general outline of the theory and methods applied using multipath flow meters. The multi-path type meter provides state of the art gas flow measurements and its accuracy and reliability satisfy the requirements for custody transfer. A typical multi-path device can achieve accuracies better than 0.2%.

  7. Program computes orifice-meter flow rate

    SciTech Connect

    Martin, J.R.

    1981-10-12

    Useful for designing new metering stations or figuring flow rates through existing ones, the program developed for the Tl-59 programmable calculator computes the gas flow rate through an orifice-meter run. The user inputs are the orifice diameter, meter run ID, flowing gas temperature, density, flowing gas pressure, and differential pressure. The program's results are more accurate than those of flow charts or slide-rule-type calculators.

  8. Balanced Flow Meters without Moving Parts

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.; VanBuskirk, Paul

    2008-01-01

    Balanced flow meters are recent additions to an established class of simple, rugged flow meters that contain no moving parts in contact with flow and are based on measurement of pressure drops across objects placed in flow paths. These flow meters are highly accurate, minimally intrusive, easily manufacturable, and reliable. A balanced flow meter can be easily mounted in a flow path by bolting it between conventional pipe flanges. A balanced flow meter can be used to measure the flow of any of a variety of liquids or gases, provided that it has been properly calibrated. Relative to the standard orifice-plate flow meter, the balanced flow meter introduces less turbulence and two times less permanent pressure loss and is therefore capable of offering 10 times greater accuracy and repeatability with less dissipation of energy. A secondary benefit of the reduction of turbulence is the reduction of vibration and up to 15 times less acoustic noise generation. Both the balanced flow meter and the standard orifice-plate flow meter are basically disks that contain holes and are instrumented with pressure transducers on their upstream and downstream faces. The most obvious difference between them is that the standard orifice plate contains a single, central hole while the balanced flow meter contains multiple holes. The term 'balanced' signifies that in designing the meter, the sizes and locations of the holes are determined in an optimization procedure that involves balancing of numerous factors, including volumetric flow, mass flow, dynamic pressure, kinetic energy, all in an effort to minimize such undesired effects as turbulence, pressure loss, dissipation of kinetic energy, and non-repeatability and nonlinearity of response over the anticipated range of flow conditions. Due to proper balancing of these factors, recent testing demonstrated that the balanced flow-meter performance was similar to a Venturi tube in both accuracy and pressure recovery, but featured reduced

  9. Noradrenaline from Locus Coeruleus Neurons Acts on Pedunculo-Pontine Neurons to Prevent REM Sleep and Induces Its Loss-Associated Effects in Rats

    PubMed Central

    Khanday, Mudasir Ahmad; Somarajan, Bindu I.; Mehta, Rachna

    2016-01-01

    Normally, rapid eye movement sleep (REMS) does not appear during waking or non-REMS. Isolated, independent studies showed that elevated noradrenaline (NA) levels inhibit REMS and induce REMS loss-associated cytomolecular, cytomorphological, psychosomatic changes and associated symptoms. However, the source of NA and its target in the brain for REMS regulation and function in health and diseases remained to be confirmed in vivo. Using tyrosine hydroxylase (TH)-siRNA and virus-coated TH-shRNA in normal freely moving rats, we downregulated NA synthesis in locus coeruleus (LC) REM-OFF neurons in vivo. These TH-downregulated rats showed increased REMS, which was prevented by infusing NA into the pedunculo-pontine tegmentum (PPT), the site of REM-ON neurons, normal REMS returned after recovery. Moreover, unlike normal or control-siRNA- or shRNA-injected rats, upon REMS deprivation (REMSD) TH-downregulated rat brains did not show elevated Na-K ATPase (molecular changes) expression and activity. To the best of our knowledge, these are the first in vivo findings in an animal model confirming that NA from the LC REM-OFF neurons (1) acts on the PPT REM-ON neurons to prevent appearance of REMS, and (2) are responsible for inducing REMSD-associated molecular changes and symptoms. These observations clearly show neuro-physio-chemical mechanism of why normally REMS does not appear during waking. Also, that LC neurons are the primary source of NA, which in turn causes some, if not many, REMSD-associated symptoms and behavioral changes. The findings are proof-of-principle for the first time and hold potential to be exploited for confirmation toward treating REMS disorder and amelioration of REMS loss-associated symptoms in patients. PMID:27957531

  10. NEUTRONIC REACTOR

    DOEpatents

    Hurwitz, H. Jr.; Brooks, H.; Mannal, C.; Payne, J.H.; Luebke, E.A.

    1959-03-24

    A reactor of the heterogeneous, liquid cooled type is described. This reactor is comprised of a central region of a plurality of vertically disposed elongated tubes surrounded by a region of moderator material. The central region is comprised of a central core surrounded by a reflector region which is surrounded by a fast neutron absorber region, which in turn is surrounded by a slow neutron absorber region. Liquid sodium is used as the primary coolant and circulates through the core which contains the fuel elements. Control of the reactor is accomplished by varying the ability of the reflector region to reflect neutrons back into the core of the reactor. For this purpose the reflector is comprised of moderator and control elements having varying effects on reactivity, the control elements being arranged and actuated by groups to give regulation, shim, and safety control.

  11. Model Performance of Water-Current Meters

    USGS Publications Warehouse

    Fulford, J.M.; ,

    2002-01-01

    The measurement of discharge in natural streams requires hydrographers to use accurate water-current meters that have consistent performance among meters of the same model. This paper presents the results of an investigation into the performance of four models of current meters - Price type-AA, Price pygmy, Marsh McBirney 2000 and Swoffer 2100. Tests for consistency and accuracy for six meters of each model are summarized. Variation of meter performance within a model is used as an indicator of consistency, and percent velocity error that is computed from a measured reference velocity is used as an indicator of meter accuracy. Velocities measured by each meter are also compared to the manufacturer's published or advertised accuracy limits. For the meters tested, the Price models werer found to be more accurate and consistent over the range of test velocities compared to the other models. The Marsh McBirney model usually measured within its accuracy specification. The Swoffer meters did not meet the stringent Swoffer accuracy limits for all the velocities tested.

  12. NEUTRONIC REACTOR

    DOEpatents

    Fermi, E.; Szilard, L.

    1957-09-24

    Reactors of the type employing plates of natural uranium in a moderator are discussed wherein the plates are um-formly disposed in parallel relationship to each other thereby separating the moderator material into distinct and individual layers. Each plate has an uninterrupted sunface area substantially equal to the cross-sectional area of the active portion of the reactor, the particular size of the plates and the volume ratio of moderator to uranium required to sustain a chain reaction being determinable from the known purity of these materials and other characteristics such as the predictable neutron losses due to the formation of radioactive elements of extremely high neutron capture cross section.

  13. NEUTRONIC REACTOR

    DOEpatents

    Wigner, E.P.; Weinberg, A.W.; Young, G.J.

    1958-04-15

    A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

  14. Spatial and Reversal Learning in the Morris Water Maze Are Largely Resistant to Six Hours of REM Sleep Deprivation Following Training

    ERIC Educational Resources Information Center

    Walsh, Christine M.; Booth, Victoria; Poe, Gina R.

    2011-01-01

    This first test of the role of REM (rapid eye movement) sleep in reversal spatial learning is also the first attempt to replicate a much cited pair of papers reporting that REM sleep deprivation impairs the consolidation of initial spatial learning in the Morris water maze. We hypothesized that REM sleep deprivation following training would impair…

  15. Development and construction of a neutron beam line for accelerator-based boron neutron capture synovectomy.

    PubMed

    Gierga, D P; Yanch, J C; Shefer, R E

    2000-01-01

    A potential application of the 10B(n, alpha)7Li nuclear reaction for the treatment of rheumatoid arthritis, termed Boron Neutron Capture Synovectomy (BNCS), is under investigation. In an arthritic joint, the synovial lining becomes inflamed and is a source of great pain and discomfort for the afflicted patient. The goal of BNCS is to ablate the synovium, thereby eliminating the symptoms of the arthritis. A BNCS treatment would consist of an intra-articular injection of boron followed by neutron irradiation of the joint. Monte Carlo radiation transport calculations have been used to develop an accelerator-based epithermal neutron beam line for BNCS treatments. The model includes a moderator/reflector assembly, neutron producing target, target cooling system, and arthritic joint phantom. Single and parallel opposed beam irradiations have been modeled for the human knee, human finger, and rabbit knee joints. Additional reflectors, placed to the side and back of the joint, have been added to the model and have been shown to improve treatment times and skin doses by about a factor of 2. Several neutron-producing charged particle reactions have been examined for BNCS, including the 9Be(p,n) reaction at proton energies of 4 and 3.7 MeV, the 9Be(d,n) reaction at deuteron energies of 1.5 and 2.6 MeV, and the 7Li(p,n) reaction at a proton energy of 2.5 MeV. For an accelerator beam current of 1 mA and synovial boron uptake of 1000 ppm, the time to deliver a therapy dose of 10,000 RBEcGy ranges from 3 to 48 min, depending on the treated joint and the neutron producing charged particle reaction. The whole-body effective dose that a human would incur during a knee treatment has been estimated to be 3.6 rem or 0.75 rem, for 1000 ppm or 19,000 ppm synovial boron uptake, respectively, although the shielding configuration has not yet been optimized. The Monte Carlo design process culminated in the construction, installation, and testing of a dedicated BNCS beam line on the high

  16. REM sleep enhancement of probabilistic classification learning is sensitive to subsequent interference.

    PubMed

    Barsky, Murray M; Tucker, Matthew A; Stickgold, Robert

    2015-07-01

    During wakefulness the brain creates meaningful relationships between disparate stimuli in ways that escape conscious awareness. Processes active during sleep can strengthen these relationships, leading to more adaptive use of those stimuli when encountered during subsequent wake. Performance on the Weather Prediction Task (WPT), a well-studied measure of implicit probabilistic learning, has been shown to improve significantly following a night of sleep, with stronger initial learning predicting more nocturnal REM sleep. We investigated this relationship further, studying the effect on WPT performance of a daytime nap containing REM sleep. We also added an interference condition after the nap/wake period as an additional probe of memory strength. Our results show that a nap significantly boosts WPT performance, and that this improvement is correlated with the amount of REM sleep obtained during the nap. When interference training is introduced following the nap, however, this REM-sleep benefit vanishes. In contrast, following an equal period of wake, performance is both unchanged from training and unaffected by interference training. Thus, while the true probabilistic relationships between WPT stimuli are strengthened by sleep, these changes are selectively susceptible to the destructive effects of retroactive interference, at least in the short term.

  17. REM Dreaming and Cognitive Skills at Ages 5-8: A Cross-Sectional Study.

    ERIC Educational Resources Information Center

    Foulkes, David; And Others

    1990-01-01

    Describes laboratory research on REM (rapid eye movement) sleep in children ages five to eight. Image quality, self-representation, and narrative complexity of dreams all develop as age progresses. Children's representational intelligence predicts their rate of dream production, but language skills do not. (GH)

  18. A5 cells are silenced when REM sleep-like signs are elicited by pontine carbachol.

    PubMed

    Fenik, Victor; Marchenko, Vitaliy; Janssen, Patrick; Davies, Richard O; Kubin, Leszek

    2002-10-01

    The A5 noradrenergic neurons are considered important for cardiorespiratory regulation. We hypothesized that A5 cells are silenced during rapid eye movement (REM) sleep, thereby contributing to cardiorespiratory changes and suppression of hypoglossal (XII) motoneuronal activity. We used an anesthetized, paralyzed, and artificially ventilated rat in which pontine microinjections of carbachol trigger signs of REM sleep, including hippocampal theta rhythm, motor suppression, and silencing of locus coeruleus neurons. All 16 putative noradrenergic A5 cells recorded were strongly suppressed when the REM sleep-like episodes were elicited and also after intravenous clonidine. Antidromic mapping showed that none of six neurons tested projected to the XII nucleus, whereas three of five projected to the nucleus of the solitary tract and two of four to the rostral ventrolateral medulla. Bilateral microinjections of clonidine into the A5 regions did not alter XII nerve activity. These data suggest that A5 neurons are silenced during natural REM sleep. This will lead to decreased norepinephrine release and may alter synaptic transmission in the nucleus of the solitary tract and rostral ventrolateral medulla without, however, a detectable impact on XII motoneurons.

  19. REM theta activity enhances inhibitory control in typically developing children but not children with ADHD symptoms.

    PubMed

    Cremone, Amanda; Lugo-Candelas, Claudia I; Harvey, Elizabeth A; McDermott, Jennifer M; Spencer, Rebecca M C

    2017-02-28

    Sleep disturbances impair cognitive functioning in typically developing populations. Children with attention-deficit/hyperactivity disorder (ADHD), a disorder characterized by impaired inhibitory control and attention, commonly experience sleep disturbances. Whether inhibitory impairments are related to sleep deficits in children with ADHD is unknown. Children with ADHD (n = 18; M age = 6.70 years) and typically developing controls (n = 15; M age = 6.73 years) completed a Go/No-Go task to measure inhibitory control and sustained attention before and after polysomnography-monitored overnight sleep. Inhibitory control and sustained attention were improved following overnight sleep in typically developing children. Moreover, morning inhibitory control was positively correlated with rapid eye movement (REM) theta activity in this group. Although REM theta activity was greater in children with ADHD compared to typically developing children, it was functionally insignificant. Neither inhibitory control nor sustained attention was improved following overnight sleep in children with ADHD symptoms, and neither of these behaviors was associated with REM theta activity in this group. Taken together, these results indicate that elevated REM theta activity may be functionally related to ADHD symptomology, possibly reflecting delayed cortical maturation.

  20. Hypothalamic L-Histidine Decarboxylase Is Up-Regulated During Chronic REM Sleep Deprivation of Rats

    PubMed Central

    Hoffman, Gloria E.; Koban, Michael

    2016-01-01

    A competition of neurobehavioral drives of sleep and wakefulness occurs during sleep deprivation. When enforced chronically, subjects must remain awake. This study examines histaminergic neurons of the tuberomammillary nucleus of the posterior hypothalamus in response to enforced wakefulness in rats. We tested the hypothesis that the rate-limiting enzyme for histamine biosynthesis, L-histidine decarboxylase (HDC), would be up-regulated during chronic rapid eye movement sleep deprivation (REM-SD) because histamine plays a major role in maintaining wakefulness. Archived brain tissues of male Sprague Dawley rats from a previous study were used. Rats had been subjected to REM-SD by the flowerpot paradigm for 5, 10, or 15 days. For immunocytochemistry, rats were transcardially perfused with acrolein-paraformaldehyde for immunodetection of L-HDC; separate controls used carbodiimide-paraformaldehyde for immunodetection of histamine. Immunolocalization of histamine within the tuberomammillary nucleus was validated using carbodiimide. Because HDC antiserum has cross-reactivity with other decarboxylases at high antibody concentrations, titrations localized L-HDC to only tuberomammillary nucleus at a dilution of ≥ 1:300,000. REM-SD increased immunoreactive HDC by day 5 and it remained elevated in both dorsal and ventral aspects of the tuberomammillary complex. Our results suggest that up-regulation of L-HDC within the tuberomammillary complex during chronic REM-SD may be responsible for maintaining wakefulness. PMID:27997552

  1. Loss of Gnas Imprinting Differentially Affects REM/NREM Sleep and Cognition in Mice

    PubMed Central

    Lassi, Glenda; Ball, Simon T.; Maggi, Silvia; Colonna, Giovanni; Nieus, Thierry; Cero, Cheryl; Bartolomucci, Alessandro; Peters, Jo; Tucci, Valter

    2012-01-01

    It has been suggested that imprinted genes are important in the regulation of sleep. However, the fundamental question of whether genomic imprinting has a role in sleep has remained elusive up to now. In this work we show that REM and NREM sleep states are differentially modulated by the maternally expressed imprinted gene Gnas. In particular, in mice with loss of imprinting of Gnas, NREM and complex cognitive processes are enhanced while REM and REM–linked behaviors are inhibited. This is the first demonstration that a specific overexpression of an imprinted gene affects sleep states and related complex behavioral traits. Furthermore, in parallel to the Gnas overexpression, we have observed an overexpression of Ucp1 in interscapular brown adipose tissue (BAT) and a significant increase in thermoregulation that may account for the REM/NREM sleep phenotypes. We conclude that there must be significant evolutionary advantages in the monoallelic expression of Gnas for REM sleep and for the consolidation of REM–dependent memories. Conversely, biallelic expression of Gnas reinforces slow wave activity in NREM sleep, and this results in a reduction of uncertainty in temporal decision-making processes. PMID:22589743

  2. REM restriction persistently alters strategy used to solve a spatial task

    PubMed Central

    Bjorness, Theresa E.; Riley, Brett T.; Tysor, Michael K.; Poe, Gina R.

    2005-01-01

    We tested the hypothesis that rapid eye movement (REM) sleep is important for complex associative learning by restricting rats from entering REM sleep for 4 h either immediately after training on an eight-box spatial task (0-4 REMr) or 4 h following training (4-8 REMr). Both groups of REM-restricted rats eventually reached the same overall performance level as did nonrestricted controls, but 0-4 REMr animals were delayed in their improvement in the first few days and lagged behind controls in the middle portion of the training period. More importantly, performance gains of 0-4 REMr rats depended more on simple local cues throughout the 15-d study since, unlike control and 4-8 REMr animals, their error rate increased after daily disruption of the relationship between local (intramaze) cues and the food reward. Thus, although overall performance was only subtly and transiently impaired, due to the ability to use alternate, nonspatial behavioral strategies, complex associative (spatial) learning was persistently impaired by restricting REM for a short critical period each day. PMID:15897251

  3. Periodic leg movements and REM sleep without atonia in Parkinson's disease with camptocormia.

    PubMed

    Lavault, Sophie; Bloch, Frederic; Houeto, Jean-Luc; Konofal, Eric; Welter, Marie-Laure; Agid, Yves; Arnulf, Isabelle

    2009-12-15

    Camptocormia (a flexion of the trunk that only appears when standing or walking) affects a minority of patients with Parkinson's disease (PD). As it responds poorly to levodopa and is associated with reduced midbrain and pons volume, it may result from non-dopaminergic, brainstem lesions. As several sleep abnormalities in PD also result from non-dopaminergic brainstem lesions, we monitored sleep in 24 non-demented PD patients with (n = 12) and without (n = 12) camptocormia and in 12 controls. Nearly half (42%) patients with camptocormia had abnormal periodic leg movement indices (>15/h), versus 17% patients without camptocormia and 8% of controls (p = 0.02). In addition, the percentage of enhanced muscle activity during REM sleep (measured on the chin and on the limb muscles) tended to be higher in patients with than without camptocormia (51 +/- 39% vs. 20 +/- 25%, p = 0.06). The other sleep and REM sleep characteristics (sleep and REM sleep onset latencies, sleep time and sleep stage percentages, REMs density, arousal, and apnea-hypopnea indices) were not different between these two PD groups. Lesions causing this axial dystonia may spare the sleep systems but affect the control of movements during sleep.

  4. The Memory Function of Noradrenergic Activity in Non-REM Sleep

    ERIC Educational Resources Information Center

    Gais, Steffen; Rasch, Bjorn; Dahmen, Johannes C.; Sara, Susan; Born, Jan

    2011-01-01

    There is a long-standing assumption that low noradrenergic activity during sleep reflects mainly the low arousal during this brain state. Nevertheless, recent research has demonstrated that the locus coeruleus, which is the main source of cortical noradrenaline, displays discrete periods of intense firing during non-REM sleep, without any signs of…

  5. REM sleep behaviour disorder in older individuals: epidemiology, pathophysiology and management.

    PubMed

    Trotti, Lynn Marie

    2010-06-01

    Rapid eye movement (REM) sleep behaviour disorder (RBD) is a sleep disorder in which patients appear to be enacting their dreams while in REM sleep. The behaviours are typically violent, in association with violent dream content, so serious harm can be done to the patient or the bed partner. The disorder predominantly affects older adults, and has an estimated prevalence in adults of 0.4-0.5%. However, the frequency is much higher in certain neurodegenerative diseases, especially Parkinson's disease, dementia with Lewy bodies and multiple systems atrophy. RBD can occur in the absence of diagnosed neurological diseases (the 'idiopathic' form), although patients with this form of RBD may have subtle neurological abnormalities and often ultimately develop a neurodegenerative disorder. Data from animal models and cases of RBD developing after brainstem (pontine tegmentum, medulla) lesions have led to the understanding that RBD is caused by a lack of normal REM muscle atonia and a lack of normal suppression of locomotor generators during REM sleep. Clonazepam is used as first-line therapy for RBD and melatonin as second-line therapy, although evidence for both of these interventions comes from uncontrolled case series. Because the risk of injury to the patient or the bed partner is high, interventions to improve the safety of the sleep environment are also often necessary. This review describes the epidemiology, pathophysiology and treatment of RBD.

  6. The effect of mood on sleep onset latency and REM sleep in interepisode bipolar disorder.

    PubMed

    Talbot, Lisa S; Hairston, Ilana S; Eidelman, Polina; Gruber, June; Harvey, Allison G

    2009-08-01

    The present study investigates whether interepisode mood regulation impairment contributes to disturbances in sleep onset latency (SOL) and rapid eye movement (REM) sleep. Individuals with interepisode bipolar disorder (n = 28) and healthy controls (n = 28) slept in the laboratory for 2 baseline nights, a happy mood induction night, and a sad mood induction night. There was a significant interaction whereby on the happy mood induction night the bipolar group exhibited significantly longer SOL than did the control group, while there was no difference on the baseline nights. In addition, control participants exhibited shorter SOL on the happy mood induction night compared to the baseline nights, a finding that was not observed in the bipolar group. On the sad mood induction night, participants in both groups had shorter SOL and increased REM density when compared to the baseline nights. Bipolar participants exhibited heightened REM density compared to control participants on both nights. These results raise the possibility that regulation of positive stimuli may be a contributor to difficulties with SOL, while hyperactivity may be characteristic of REM sleep.

  7. Coherent neocortical 40-Hz oscillations are not present during REM sleep.

    PubMed

    Castro, Santiago; Falconi, Atilio; Chase, Michael H; Torterolo, Pablo

    2013-04-01

    During cognitive processes there are extensive interactions between various regions of the cerebral cortex. Oscillations in the gamma frequency band (≈40 Hz) of the electroencephalogram (EEG) are involved in the binding of spatially separated but temporally correlated neural events, which results in a unified perceptual experience. The extent of these interactions can be examined by means of a mathematical algorithm called 'coherence', which reflects the 'strength' of functional interactions between cortical areas. The present study was conducted to analyse EEG coherence in the gamma frequency band of the cat during alert wakefulness (AW), quiet wakefulness (QW), non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Cats were implanted with electrodes in the frontal, parietal and occipital cortices to monitor EEG activity. Coherence values within the gamma frequency (30-100 Hz) from pairs of EEG recordings were analysed. A large increase in coherence occurred between all cortical regions in the 30-45 Hz frequency band during AW compared with the other behavioral states. As the animal transitioned from AW to QW and from QW to NREM sleep, coherence decreased to a moderate level. Remarkably, there was practically no EEG coherence in the entire gamma band spectrum (30-100 Hz) during REM sleep. We conclude that functional interactions between cortical areas are radically different during sleep compared with wakefulness. The virtual absence of gamma frequency coherence during REM sleep may underlie the unique cognitive processing that occurs during dreams, which is principally a REM sleep-related phenomenon.

  8. Hypothalamic L-Histidine Decarboxylase Is Up-Regulated During Chronic REM Sleep Deprivation of Rats.

    PubMed

    Hoffman, Gloria E; Koban, Michael

    2016-01-01

    A competition of neurobehavioral drives of sleep and wakefulness occurs during sleep deprivation. When enforced chronically, subjects must remain awake. This study examines histaminergic neurons of the tuberomammillary nucleus of the posterior hypothalamus in response to enforced wakefulness in rats. We tested the hypothesis that the rate-limiting enzyme for histamine biosynthesis, L-histidine decarboxylase (HDC), would be up-regulated during chronic rapid eye movement sleep deprivation (REM-SD) because histamine plays a major role in maintaining wakefulness. Archived brain tissues of male Sprague Dawley rats from a previous study were used. Rats had been subjected to REM-SD by the flowerpot paradigm for 5, 10, or 15 days. For immunocytochemistry, rats were transcardially perfused with acrolein-paraformaldehyde for immunodetection of L-HDC; separate controls used carbodiimide-paraformaldehyde for immunodetection of histamine. Immunolocalization of histamine within the tuberomammillary nucleus was validated using carbodiimide. Because HDC antiserum has cross-reactivity with other decarboxylases at high antibody concentrations, titrations localized L-HDC to only tuberomammillary nucleus at a dilution of ≥ 1:300,000. REM-SD increased immunoreactive HDC by day 5 and it remained elevated in both dorsal and ventral aspects of the tuberomammillary complex. Our results suggest that up-regulation of L-HDC within the tuberomammillary complex during chronic REM-SD may be responsible for maintaining wakefulness.

  9. Association between Glucose Metabolism and Sleep-disordered Breathing during REM Sleep

    PubMed Central

    Gottlieb, Daniel J.; Redline, Susan; Punjabi, Naresh M.

    2015-01-01

    Rationale: Sleep-disordered breathing (SDB) has been associated with impaired glucose metabolism. It is possible that the association between SDB and glucose metabolism is distinct for non-REM versus REM sleep because of differences in sleep-state–dependent sympathetic activation and/or degree of hypoxemia. Objectives: To characterize the association between REM-related SDB, glucose intolerance, and insulin resistance in a community-based sample. Methods: A cross-sectional analysis that included 3,310 participants from the Sleep Heart Health Study was undertaken (53% female; mean age, 66.1 yr). Full montage home-polysomnography and fasting glucose were available on all participants. SDB severity during REM and non-REM sleep was quantified using the apnea–hypopnea index in REM (AHIREM) and non-REM sleep (AHINREM), respectively. Fasting and 2-hour post-challenge glucose levels were assessed during a glucose tolerance test (n = 2,264). The homeostatic model assessment index for insulin resistance (HOMA-IR) was calculated (n = 1,543). Linear regression was used to assess the associations of AHIREM and AHINREM with fasting and post-prandial glucose levels and HOMA-IR. Measurements and Main Results: AHIREM and AHINREM were associated with fasting glycemia, post-prandial glucose levels, and HOMA-IR in models that adjusted for age, sex, race, and site. However, with additional adjustment for body mass index, waist circumference, and sleep duration, AHIREM was only associated with HOMA-IR (β = 0.04; 95% CI, 0.1–0.07; P = 0.01), whereas AHINREM was only associated with fasting (β = 0.93; 95% CI, 0.14–1.72; P = 0.02) and post-prandial glucose levels (β = 3.0; 95% CI, 0.5–5.5; P = 0.02). Conclusions: AHIREM is associated with insulin resistance but not with fasting glycemia or glucose intolerance. PMID:26200994

  10. A restricted parabrachial pontine region is active during non-REM sleep

    PubMed Central

    Torterolo, Pablo; Sampogna, Sharon; Chase, Michael H.

    2011-01-01

    The principal site that generates both REM sleep and wakefulness is located in the mesopontine reticular formation, whereas non-REM sleep (NREM) is primarily dependent upon the functioning of neurons that are located in the preoptic region of the hypothalamus. In the present study, we were interested in determining whether the occurrence of NREM might also depend on the activity of mesopontine structures, as has been shown for wakefulness and REM sleep. Adult cats were maintained in one of the following states: quiet wakefulness (QW), alert wakefulness (AW), NREM, or REM sleep induced by microinjections of carbachol into the nucleus pontis oralis (REM-carbachol). Subsequently, they were euthanized and single labeling immunohistochemical studies were undertaken to determine state-dependent patterns of neuronal activity in the brainstem based upon the expression of the protein Fos. In addition, double labeling immunohistochemical studies were carried out to detect neurons that expressed Fos as well as choline acetyltransferase, tyrosine hydroxylase or GABA. During NREM, only a few Fos immunoreactive cells were present in different regions of the brainstem; however, a discrete cluster of Fos+ neurons was observed in the caudolateral peribrachial region (CLPB). The number of the Fos+ neurons in the CLPB during NREM was significantly greater (67.9 ± 10.9, P < 0.0001) compared to QW (8.0 ± 6.7), AW (5.2 ± 4.2) or REM-carbachol (8.0 ± 4.7). In addition, there was a positive correlation (R = 0.93) between the time the animals spent in NREM and the number of Fos+ neurons in the CLPB. Fos-immunoreactive neurons in the CLPB were neither cholinergic nor catecholaminergic; however about 50% of these neurons were GABAergic. We conclude that a group of GABAergic and unidentified neurons in the CLPB are active during NREM and likely involved in the control of this behavioral state. These data open new avenues for the study of NREM, as well as for the explorations of

  11. Electroencephalographic and autonomic alterations in subjects with frequent nightmares during pre-and post-REM periods.

    PubMed

    Simor, Péter; Körmendi, János; Horváth, Klára; Gombos, Ferenc; Ujma, Péter P; Bódizs, Róbert

    2014-11-01

    Abnormal arousal processes, sympathetic influences, as well as wake-like alpha activity during sleep were reported as pathophysiological features of Nightmare Disorder. We hypothesized that in Nightmare Disorder, wake-like cortical activity and peripheral measures linked to arousals would be triggered by physiological processes related to the initiation of REM periods. Therefore, we examined electroencephalographic (EEG), motor and autonomous (cardiac) activity in a group of nightmare (NM) and healthy control (CTL) subjects during sleep-state-transitions while controlling for the confounding effects of trait anxiety. Based on the second-nights' polysomnographic recordings of 19 Nightmare Disordered (NM) and 21 control (CTL) subjects, we examined the absolute power spectra focusing on the alpha range, measures of heart rate variability (HRV) and motor (muscle tone) activity during pre-REM and post-REM periods, separately. According to our results, the NM group exhibited increased alpha power during pre-REM, but not in post-REM, or stable, non-transitory periods. While CTL subjects showed increased HRV during pre-REM periods in contrast to post-REM ones, NM subjects did not exhibit such sleep state-specific differences in HRV, but showed more stable values across the examined sleep stages and less overall variability reflecting generally attenuated parasympathetic activity during sleep-state-transitions and during stable, non-transitory NREM states. These differences were not mediated by waking levels of trait anxiety. Moreover, in both groups, significant differences emerged regarding cortical and motor (muscle tone) activity between pre-REM and post-REM conditions, reflecting the heterogeneity of NREM sleep. Our findings indicate that NM subjects' sleep is compromised during NREM-REM transitions, but relatively stabilized after REM periods. The coexistence of sleep-like and wake-like cortical activity in NM subjects seems to be triggered by REM/WAKE promoting

  12. The Antarctic permafrost as a testbed for REMS (Rover Environmental Monitoring Station-Mars Science Laboratory)

    NASA Astrophysics Data System (ADS)

    Esteban, B.; Ramos, M.; Sebastián, E.; Armiens, C.; Gómez-Elvira, J.; Cabos, W.; de Pablo, M. A.

    2009-04-01

    The present climatic characteristics of Mars favor the presence of extense permafrost areas in this lonely planet. Therefore environmental parameters that are included in Martian Rover missions are also used for monitoring thermal soil surface evolution in order to study the permafrost active layer thickness and the energy balance in the soil-atmosphere boundary limit layer. The REMS (Rover Environmental Monitoring Station) is an environmental station designed by the Centro de Astrobiología (CAB- Spain) with the collaboration of national and international partners (CRISA/EADS, UPC and FMI), which is part of the payload of the MSL (Mars Science Laboratory) NASA mission to Mars (http://mars.jpl.nasa.gov/msl/overview/). This mission is expected to be launched in the final months of 2009, and mainly consists of a Rover, with a complete set of scientific instruments; the Rover will carry the biggest, most advanced suite of instruments for scientific studies ever sent to the Martian surface. Five sensors compose the REMS instrument: ground (GT-REMS) and air temperatures, wind speed and direction, pressure, humidity and ultraviolet radiation (UV-REMS). A simplified setup of the REMS was deployed on Antarctica in the surroundings of the Spanish Antarctic Stations on Livingston and Deception Islands (Maritime Antarctica), where the permafrost distribution is well-known. The aim of the experiment was to check REMS's sensors response against hard environmental conditions and calibrates their measures with standard Antarctic devices. The experimental apparatuses included some standard meteorological and thermopiles sensors corresponding to the REMS. All the sensors are mounted in a 1.8 m mast and include a Pt100 air temperature sensor with shield solar protection on the mast top, a Kipp and Zonnen CNR1 net radiometer for measuring infrared (5-50 μm) and short wave solar (305-2800 nm) radiation at 1.5 m high, GT-REMS sensor and its amplification box at 0.7 m high and finally

  13. Neutronic reactor

    DOEpatents

    Carleton, John T.

    1977-01-25

    A graphite-moderated nuclear reactor includes channels between blocks of graphite and also includes spacer blocks between adjacent channeled blocks with an axis of extension normal to that of the axis of elongation of the channeled blocks to minimize changes in the physical properties of the graphite as a result of prolonged neutron bombardment.

  14. NEUTRONIC REACTORS

    DOEpatents

    Anderson, H.L.

    1958-10-01

    The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.

  15. Interpretation of the Meteorological Gale Environment through Mars Science Laboratory (MSL) Rover Environmental Monitoring Station (REMS) Observations and Mesoscale Modeling (MRAMS)

    NASA Astrophysics Data System (ADS)

    Pla-García, J.; Rafkin, S. C.; Gómez-Elvira, J.; Martín-Torres, J.; Zorzano, M. P.

    2014-12-01

    Gale Crater, in which the Mars Science Laboratory (MSL) landed in August 2012, is the most topographically complex area visited to date on Mars. The meteorology within the crater may also be one of the most dynamically complex meteorological environments, because topography is thought to strongly drive the near-surface atmospheric circulations. The Rover Environmental Monitoring Station (REMS) on the Curiosity rover consists of a suite of meteorological instruments that measure pressure, temperature (air and ground), wind (speed and direction), relative humidity, and the UV flux. REMS has provided some clues on the nature of the local meteorology strongly influenced by the complex topography, as predicted by numerous previous studies. As with all single station measurements, the meteorological interpretation is typically hindered by a lack of spatial context in which to place the observations. Numerical modeling results, when properly validated against observations, can provide interpretive context. In an effort to better understand the atmospheric circulations of the Gale Crater, the Mars Regional Atmospheric Modeling System (MRAMS) was applied to the landing site region using nested grids with a spacing of 330 meters on the innermost grid that is centered over the landing site. MRAMS is ideally suited for this investigation; the model is explicitly designed to simulate Mars' atmospheric circulations at the mesoscale and smaller with realistic, high resolution surface properties. Simulations with MRAMS indicate thermal and wind thermal signatures associated with slope flows, katabatic winds, and nocturnal mixing events that are consistent with the rover environment monitored by REMS. Of particular note is evidence for two distinct air masses—one in the bottom of the crater (a relatively cold potential temperature air mass) and one on the plateau—that have minimal interaction with one another. If there are indeed two distinct air masses, there are strong

  16. Methods for absorbing neutrons

    DOEpatents

    Guillen, Donna P [Idaho Falls, ID; Longhurst, Glen R [Idaho Falls, ID; Porter, Douglas L [Idaho Falls, ID; Parry, James R [Idaho Falls, ID

    2012-07-24

    A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

  17. Variety of neutron sensors based on scintillating glass waveguides

    NASA Astrophysics Data System (ADS)

    Bliss, Mary; Craig, Richard A.

    1995-04-01

    Pacific Northwest Laboratory (PNL) has fabricated cerium-activated lithium silicate glass scintillating fiber waveguide neutron sensors via a hot-downdraw process. These fibers typically have a transmission length (e-1 length) of greater than 2 meters. The underlying physics of, the properties of, and selected devices incorporating these fibers are described. These fibers constitute an enabling technology for a wide variety of neutron sensors.

  18. Locus Coeruleus and Tuberomammillary Nuclei Ablations Attenuate Hypocretin/Orexin Antagonist-Mediated REM Sleep.

    PubMed

    Schwartz, Michael D; Nguyen, Alexander T; Warrier, Deepti R; Palmerston, Jeremiah B; Thomas, Alexia M; Morairty, Stephen R; Neylan, Thomas C; Kilduff, Thomas S

    2016-01-01

    Hypocretin 1 and 2 (Hcrts; also known as orexin A and B), excitatory neuropeptides synthesized in cells located in the tuberal hypothalamus, play a central role in the control of arousal. Hcrt inputs to the locus coeruleus norepinephrine (LC NE) system and the posterior hypothalamic histaminergic tuberomammillary nuclei (TMN HA) are important efferent pathways for Hcrt-induced wakefulness. The LC expresses Hcrt receptor 1 (HcrtR1), whereas HcrtR2 is found in the TMN. Although the dual Hcrt/orexin receptor antagonist almorexant (ALM) decreases wakefulness and increases NREM and REM sleep time, the neural circuitry that mediates these effects is currently unknown. To test the hypothesis that ALM induces sleep by selectively disfacilitating subcortical wake-promoting populations, we ablated LC NE neurons (LCx) or TMN HA neurons (TMNx) in rats using cell-type-specific saporin conjugates and evaluated sleep/wake following treatment with ALM and the GABAA receptor modulator zolpidem (ZOL). Both LCx and TMNx attenuated the promotion of REM sleep by ALM without affecting ALM-mediated increases in NREM sleep. Thus, eliminating either HcrtR1 signaling in the LC or HcrtR2 signaling in the TMN yields similar effects on ALM-induced REM sleep without affecting NREM sleep time. In contrast, neither lesion altered ZOL efficacy on any measure of sleep-wake regulation. These results contrast with those of a previous study in which ablation of basal forebrain cholinergic neurons attenuated ALM-induced increases in NREM sleep time without affecting REM sleep, indicating that Hcrt neurotransmission influences distinct aspects of NREM and REM sleep at different locations in the sleep-wake regulatory network.

  19. Using the relational event model (REM) to investigate the temporal dynamics of animal social networks.

    PubMed

    Tranmer, Mark; Marcum, Christopher Steven; Morton, F Blake; Croft, Darren P; de Kort, Selvino R

    2015-03-01

    Social dynamics are of fundamental importance in animal societies. Studies on nonhuman animal social systems often aggregate social interaction event data into a single network within a particular time frame. Analysis of the resulting network can provide a useful insight into the overall extent of interaction. However, through aggregation, information is lost about the order in which interactions occurred, and hence the sequences of actions over time. Many research hypotheses relate directly to the sequence of actions, such as the recency or rate of action, rather than to their overall volume or presence. Here, we demonstrate how the temporal structure of social interaction sequences can be quantified from disaggregated event data using the relational event model (REM). We first outline the REM, explaining why it is different from other models for longitudinal data, and how it can be used to model sequences of events unfolding in a network. We then discuss a case study on the European jackdaw, Corvus monedula, in which temporal patterns of persistence and reciprocity of action are of interest, and present and discuss the results of a REM analysis of these data. One of the strengths of a REM analysis is its ability to take into account different ways in which data are collected. Having explained how to take into account the way in which the data were collected for the jackdaw study, we briefly discuss the application of the model to other studies. We provide details of how the models may be fitted in the R statistical software environment and outline some recent extensions to the REM framework.

  20. Evaluating Metal Probe Meters for Soil Testing.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1992-01-01

    Inexpensive metal probe meters that are sold by garden stores can be evaluated by students for their accuracy in measuring soil pH, moisture, fertility, and salinity. The author concludes that the meters are inaccurate and cannot be calibrated in standard units. However, the student evaluations are useful in learning the methods of soil analysis…

  1. Field experience with gas turbine meters

    SciTech Connect

    Hall, W.H.

    1984-04-01

    This paper discusses a company's experience and problems with turbine meters in a large offshore system. With the increased cost and decreasing reserves of natural gas, greater demands will be placed on gas measurement. Turbine meters have lent themselves well to the task and will continue to find more applications in the natural gas industry.

  2. Simplified Processing Method for Meter Data Analysis

    SciTech Connect

    Fowler, Kimberly M.; Colotelo, Alison H. A.; Downs, Janelle L.; Ham, Kenneth D.; Henderson, Jordan W.; Montgomery, Sadie A.; Vernon, Christopher R.; Parker, Steven A.

    2015-11-01

    Simple/Quick metered data processing method that can be used for Army Metered Data Management System (MDMS) and Logistics Innovation Agency data, but may also be useful for other large data sets. Intended for large data sets when analyst has little information about the buildings.

  3. Recent Advances in Neutron Physics

    ERIC Educational Resources Information Center

    Feshbach, Herman; Sheldon, Eric

    1977-01-01

    Discusses new studies in neutron physics within the last decade, such as ultracold neutrons, neutron bottles, resonance behavior, subthreshold fission, doubly radiative capture, and neutron stars. (MLH)

  4. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

  5. Neutron reflecting supermirror structure

    DOEpatents

    Wood, J.L.

    1992-12-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

  6. Endothelial function and sleep: associations of flow-mediated dilation with perceived sleep quality and rapid eye movement (REM) sleep.

    PubMed

    Cooper, Denise C; Ziegler, Michael G; Milic, Milos S; Ancoli-Israel, Sonia; Mills, Paul J; Loredo, José S; Von Känel, Roland; Dimsdale, Joel E

    2014-02-01

    Endothelial function typically precedes clinical manifestations of cardiovascular disease and provides a potential mechanism for the associations observed between cardiovascular disease and sleep quality. This study examined how subjective and objective indicators of sleep quality relate to endothelial function, as measured by brachial artery flow-mediated dilation (FMD). In a clinical research centre, 100 non-shift working adults (mean age: 36 years) completed FMD testing and the Pittsburgh Sleep Quality Index, along with a polysomnography assessment to obtain the following measures: slow wave sleep, percentage rapid eye movement (REM) sleep, REM sleep latency, total arousal index, total sleep time, wake after sleep onset, sleep efficiency and apnea-hypopnea index. Bivariate correlations and follow-up multiple regressions examined how FMD related to subjective (i.e., Pittsburgh Sleep Quality Index scores) and objective (i.e., polysomnography-derived) indicators of sleep quality. After FMD showed bivariate correlations with Pittsburgh Sleep Quality Index scores, percentage REM sleep and REM latency, further examination with separate regression models indicated that these associations remained significant after adjustments for sex, age, race, hypertension, body mass index, apnea-hypopnea index, smoking and income (Ps < 0.05). Specifically, as FMD decreased, scores on the Pittsburgh Sleep Quality Index increased (indicating decreased subjective sleep quality) and percentage REM sleep decreased, while REM sleep latency increased (Ps < 0.05). Poorer subjective sleep quality and adverse changes in REM sleep were associated with diminished vasodilation, which could link sleep disturbances to cardiovascular disease.

  7. Monoamine depletion attenuates the REM sleep deprivation-induced increase in clonidine response in the forced swimming test.

    PubMed

    Asakura, W; Matsumoto, K; Ohta, H; Watanabe, H

    1994-09-01

    Effect of monoamine depletion on the REM sleep (REMs) deprivation-induced increase in clonidine response in the forced swimming test was investigated. Mice were deprived of REMs by the small pedestal method. Clonidine HCl (10-1000 micrograms/kg, IP), an alpha 2-adrenoceptor agonist, dose dependently increased swimming activities in group-housed and socially isolated mice used as the control groups. The dose-response relationship shifted to the left following REMs deprivation (ED50 values in the group-housed, isolated, and REMs-deprived mice were 250, 200, and 27 micrograms/kg, respectively). Monoamine depletion, induced by reserpine (5 mg/kg, IP) plus alpha-methyl-p-tyrosine (250 mg/kg, IP), did not produce any changes in the effects of clonidine in the control groups. However, in REMs-deprived mice, monoamine depletion significantly decreased the effect of 100 micrograms/kg clonidine, but not that of 300 micrograms/kg clonidine on swimming activity. These results indicate that clonidine-induced increase in swimming activity in the forced swimming test is mainly mediated by postsynaptic alpha 2-adrenoceptor, and that endogenous noradrenaline in the brain plays an important role in the increase of clonidine response following REMs deprivation treatment. The neuronal mechanism of the increase in clonidine response is discussed.

  8. Chemogenetic inhibition of the medial prefrontal cortex reverses the effects of REM sleep loss on sucrose consumption

    PubMed Central

    McEown, Kristopher; Takata, Yohko; Cherasse, Yoan; Nagata, Nanae; Aritake, Kosuke; Lazarus, Michael

    2016-01-01

    Rapid eye movement (REM) sleep loss is associated with increased consumption of weight-promoting foods. The prefrontal cortex (PFC) is thought to mediate reward anticipation. However, the precise role of the PFC in mediating reward responses to highly palatable foods (HPF) after REM sleep deprivation is unclear. We selectively reduced REM sleep in mice over a 25–48 hr period and chemogenetically inhibited the medial PFC (mPFC) by using an altered glutamate-gated and ivermectin-gated chloride channel that facilitated neuronal inhibition through hyperpolarizing infected neurons. HPF consumption was measured while the mPFC was inactivated and REM sleep loss was induced. We found that REM sleep loss increased HPF consumption compared to control animals. However, mPFC inactivation reversed the effect of REM sleep loss on sucrose consumption without affecting fat consumption. Our findings provide, for the first time, a causal link between REM sleep, mPFC function and HPF consumption. DOI: http://dx.doi.org/10.7554/eLife.20269.001 PMID:27919319

  9. Hypoventilation in REM sleep in a case of 17p11.2 deletion (Smith-Magenis syndrome).

    PubMed

    Leoni, Chiara; Cesarini, Laura; Dittoni, Serena; Battaglia, Domenica; Novelli, Antonio; Bernardini, Laura; Losurdo, Anna; Vollono, Catello; Testani, Elisa; Della Marca, Giacomo; Zampino, Giuseppe

    2010-03-01

    We describe a 2-year-old baby affected by Smith-Magenis syndrome (SMS), due to 17p11.2 deletion, who presented repeated episodes of hemoglobin desaturation during REM sleep. The boy, aged 14 months, presented a phenotype characterized by psychomotor delay, right posterior plagiocephaly, telecanthus, strabismus, upslanting palpebral fissures, broad hypoplastic nasal bridge, short philtrum, deep ring shaped skin creases around the limbs, proximal syndactyly, bilateral hypoacusia. Polysomnographic (PSG) recording showed episodes of REM-related hypoventilation (hemoglobin desaturations without apneas or hypopneas). Sleep disorders are present in almost all the cases of SMS, but very few reports describe the sleep-related respiratory patterns. The finding of REM hypoventilation in SMS does not allow an unequivocal interpretation. It could reflect a subclinical restrictive respiratory impairment or, alternatively, an impairment of central respiratory control during REM sleep. In SMS children, respiratory abnormalities during sleep, and in particular during REM sleep, may cause sleep disruption, reduction of time spent in REM sleep, and daytime sleepiness. We therefore suggest that some sleep abnormalities described in SMS could be consequent to Sleep Disordered Breathing, and in particular to REM hypoventilation. Sleep studies in SMS should include the recording of respiratory parameters.

  10. Cost Benefit Analysis of Installing a Recovery Exercise Module (REM) in a Cruise Missile for an Operational Test Launch.

    DTIC Science & Technology

    1987-06-01

    A±6 454 COST BENEFIT AINALYSIS OF INSTALLING A RECOVERY EXERCISE /In N9 ODULE (REM) IN R..(U) NAVAL POSTGRADUATE SCHOOL MONTEREY CA H E GLASSNAN...BENEFIT ANALYSIS OF INSTALLING A RECOVERY EXERCISE MODULE (REM) IN A CRUISE MISSILE FOR AN OPERATIONAL TEST LAUNCH by Howard Elliott Glassman June 1987...iNI ELEMENT NO I NNO4 ACCESSION NO TITLE (InCludO Secu’fft C10uufCA1uon) COST BENEFIT ANALYSIS OF INSTALLING A RECOVERY EXERCISE MODULE (REM) IN A

  11. Effect of vertical motion on current meters

    USGS Publications Warehouse

    Kallio, Nicholas A.

    1966-01-01

    The effect of vertical motion on the performance of current meters at various stream velocities was evaluated to determine whether accurate discharge measurements can be made from a bobbing boat. Three types of current meters--Ott, Price, and vane types--were tested under conditions simulating a bobbing boat. A known frequency and amplitude of vertical motion were imparted to the current meter, and the related effect on the measured stream velocity was determined. One test of the Price meter was made under actual conditions, using a boat and standard measuring gear. The results of the test under actual conditions verified those obtained by simulating the vertical movements of a boat. The tests show that for stream velocities below 2.5 feet per second the accuracy of all three meters is significantly affected when the meters are subjected to certain conditions of vertical motion that can occur during actual field operations. Both the rate of vertical motion and the frequency of vertical oscillation affect the registration of the meter. The results of these tests, presented in the form of graphs and tables, can be used as a guide to determine whether wind and stream flow are within an acceptable range for a reliable discharge measurement from a boat.

  12. NEUTRONIC REACTORS

    DOEpatents

    Vernon, H.C.

    1959-01-13

    A neutronic reactor of the heterogeneous, fluid cooled tvpe is described. The reactor is comprised of a pressure vessel containing the moderator and a plurality of vertically disposed channels extending in spaced relationship through the moderator. Fissionable fuel material is placed within the channels in spaced relationship thereto to permit circulation of the coolant fluid. Separate means are provided for cooling the moderator and for circulating a fluid coolant thru the channel elements to cool the fuel material.

  13. Vivid dreams, hallucinations, psychosis and REM sleep in Guillain-Barré syndrome.

    PubMed

    Cochen, V; Arnulf, I; Demeret, S; Neulat, M L; Gourlet, V; Drouot, X; Moutereau, S; Derenne, J P; Similowski, T; Willer, J C; Pierrot-Deseiligny, C; Bolgert, F

    2005-11-01

    We conducted a prospective controlled study of the clinical and biological determinants of the mental status abnormalities in 139 patients with Guillain-Barré syndrome (GBS) and 55 patients without GBS placed in the intensive care unit (ICU controls). There were mental status changes in 31% of GBS patients and in 16% of controls (odds ratio = 2.3; P = 0.04). In GBS patients, they included vivid dreams (19%), illusions (30%, including an illusory body tilt), hallucinations (60%, mainly visual) and delusions (70%, mostly paranoid). They appeared a median 9 days after disease onset (range 1-40 days, during the progression or the plateau of the disease), and lasted a median 8 days. Seven (16%) patients experienced the symptoms before their admission to the ICU. Hallucinations were frequently hypnagogic, occurring as soon as the patients closed their eyes. Autonomic dysfunction, assisted ventilation and high CSF protein levels were significant risk factors for abnormal mental status in GBS patients. CSF hypocretin-1 (a hypothalamic neuropeptide deficient in narcolepsy) levels, measured in 20 patients, were lower in GBS patients with hallucinations (555 +/- 132 pg/ml) than in those without (664 +/- 71 pg/ml, P = 0.03). Since the mental status abnormalities had dream-like aspects, we examined their association with rapid eye movement sleep (REM sleep) using continuous sleep monitoring in 13 GBS patients with (n = 7) and without (n = 6) hallucinations and 6 tetraplegic ICU controls without hallucinations. Although sleep was short and fragmented in all groups, REM sleep latency was shorter in GBS patients with hallucinations (56 +/- 115 min) than in GBS patients without hallucinations (153 +/- 130 min) and in controls (207 +/- 179 min, P < 0.05). In addition, sleep structure was highly abnormal in hallucinators, with sleep onset in REM sleep periods (83%), abnormal eye movements during non-REM sleep (57%), high percentages of REM sleep without atonia (92 +/- 22%), REM

  14. Genetic inactivation of glutamate neurons in the rat sublaterodorsal tegmental nucleus recapitulates REM sleep behaviour disorder.

    PubMed

    Valencia Garcia, Sara; Libourel, Paul-Antoine; Lazarus, Michael; Grassi, Daniela; Luppi, Pierre-Hervé; Fort, Patrice

    2017-02-01

    SEE SCHENCK AND MAHOWALD DOI101093/AWW329 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Idiopathic REM sleep behaviour disorder is characterized by the enactment of violent dreams during paradoxical (REM) sleep in the absence of normal muscle atonia. Accumulating clinical and experimental data suggest that REM sleep behaviour disorder might be due to the neurodegeneration of glutamate neurons involved in paradoxical sleep and located within the pontine sublaterodorsal tegmental nucleus. The purpose of the present work was thus to functionally determine first, the role of glutamate sublaterodorsal tegmental nucleus neurons in paradoxical sleep and second, whether their genetic inactivation is sufficient for recapitulating REM sleep behaviour disorder in rats. For this goal, we first injected two retrograde tracers in the intralaminar thalamus and ventral medulla to disentangle neuronal circuits in which sublaterodorsal tegmental nucleus is involved; second we infused bilaterally in sublaterodorsal tegmental nucleus adeno-associated viruses carrying short hairpin RNAs targeting Slc17a6 mRNA [which encodes vesicular glutamate transporter 2 (vGluT2)] to chronically impair glutamate synaptic transmission in sublaterodorsal tegmental nucleus neurons. At the neuroanatomical level, sublaterodorsal tegmental nucleus neurons specifically activated during paradoxical sleep hypersomnia send descending efferents to glycine/GABA neurons within the ventral medulla, but not ascending projections to the intralaminar thalamus. These data suggest a crucial role of sublaterodorsal tegmental nucleus neurons rather in muscle atonia than in paradoxical sleep generation. In line with this hypothesis, 30 days after adeno-associated virus injections into sublaterodorsal tegmental nucleus rats display a decrease of 30% of paradoxical sleep daily quantities, and a significant increase of muscle tone during paradoxical sleep concomitant to a tremendous increase of abnormal motor dream

  15. Martian Surface Temperature and Spectral Response from the MSL REMS Ground Temperature Sensor

    NASA Astrophysics Data System (ADS)

    Martin-Torres, Javier; Martínez-Frías, Jesús; Zorzano, María-Paz; Serrano, María; Mendaza, Teresa; Hamilton, Vicky; Sebastián, Eduardo; Armiens, Carlos; Gómez-Elvira, Javier; REMS Team

    2013-04-01

    The Rover Environmental Monitoring Station (REMS) on the Mars Science Laboratory (MSL) offers the opportunity to explore the near surface atmospheric conditions and, in particular will shed new light into the heat budget of the Martian surface. This is important for studies of the atmospheric boundary layer (ABL), as the ground and air temperatures measured directly by REMS control the coupling of the atmosphere with the surface [Zurek et al., 1992]. This coupling is driven by solar insolation. The ABL plays an important role in the general circulation and the local atmospheric dynamics of Mars. One of the REMS sensors, the ground temperature sensor (GTS), provides the data needed to study the thermal inertia properties of the regolith and rocks beneath the MSL rover. The GTS includes thermopile detectors, with infrared bands of 8-14 µm and 16-20 µm [Gómez-Elvira et al., 2012]. These sensors are clustered in a single location on the MSL mast and the 8-14 µm thermopile sounds the surface temperature. The infrared radiation reaching the thermopile is proportional to the emissivity of the surface minerals across these thermal wavelengths. We have developed a radiative transfer retrieval method for the REMS GTS using a database of thermal infrared laboratory spectra of analogue minerals and their mixtures. [Martín Redondo et al. 2009, Martínez-Frías et al. 2012 - FRISER-IRMIX database]. This method will be used to assess the perfomance of the REMS GTS as well as determine, through the error analysis, the surface temperature and emissivity values where MSL is operating. Comparisons with orbiter data will be performed. References Gómez-Elvira et al. [2012], REMS: The Environmental Sensor Suite for the Mars Science Laboratory Rover, Space Science Reviews, Volume 170, Issue 1-4, pp. 583-640. Martín-Redondo et al. [2009] Journal of Environmental Monitoring 11:, pp. 1428-1432. Martínez-Frías et al. [2012] FRISER-IRMIX database http

  16. High-Energy Neutron Backgrounds for Underground Dark Matter Experiments

    SciTech Connect

    Chen, Yu

    2016-01-01

    Direct dark matter detection experiments usually have excellent capability to distinguish nuclear recoils, expected interactions with Weakly Interacting Massive Particle (WIMP) dark matter, and electronic recoils, so that they can efficiently reject background events such as gamma-rays and charged particles. However, both WIMPs and neutrons can induce nuclear recoils. Neutrons are then the most crucial background for direct dark matter detection. It is important to understand and account for all sources of neutron backgrounds when claiming a discovery of dark matter detection or reporting limits on the WIMP-nucleon cross section. One type of neutron background that is not well understood is the cosmogenic neutrons from muons interacting with the underground cavern rock and materials surrounding a dark matter detector. The Neutron Multiplicity Meter (NMM) is a water Cherenkov detector capable of measuring the cosmogenic neutron flux at the Soudan Underground Laboratory, which has an overburden of 2090 meters water equivalent. The NMM consists of two 2.2-tonne gadolinium-doped water tanks situated atop a 20-tonne lead target. It detects a high-energy (>~ 50 MeV) neutron via moderation and capture of the multiple secondary neutrons released when the former interacts in the lead target. The multiplicity of secondary neutrons for the high-energy neutron provides a benchmark for comparison to the current Monte Carlo predictions. Combining with the Monte Carlo simulation, the muon-induced high-energy neutron flux above 50 MeV is measured to be (1.3 ± 0.2) ~ 10-9 cm-2s-1, in reasonable agreement with the model prediction. The measured multiplicity spectrum agrees well with that of Monte Carlo simulation for multiplicity below 10, but shows an excess of approximately a factor of three over Monte Carlo prediction for multiplicities ~ 10 - 20. In an effort to reduce neutron backgrounds for the dark matter experiment SuperCDMS SNO- LAB, an active neutron veto was developed

  17. Hydrogen meter for service in liquid sodium

    SciTech Connect

    McCown, J J

    1983-11-01

    This standard establishes the requirements for the design, materials, fabrication, quality assurance, examination, and acceptance testing of a hydrogen meter and auxiliary equipment for use in radioactive or nonradioactive liquid sodium service. The meter shall provide a continuous and accurate indication of the hydrogen impurity concentration over the range 0.03 to 10 ppM hydrogen in sodium at temperatures between 800 and 1000/sup 0/F (427 and 538/sup 0/C). The meter may also be used to rapidly monitor changes in hydrogen concentration, over the same concentration range, and, therefore can be used as a sensor for sodium-water reactions in LMFBR steam generators.

  18. Characterization of Neutron Backgrounds for Direct Dark Matter Searches

    NASA Astrophysics Data System (ADS)

    Sweany, Melinda Dominique

    Direct dark matter experiments generally cannot distinguish between nuclear recoils caused by Weakly Interacting Massive Particles (WIMPs) and those caused by neutron backgrounds. It is therefore crucial that all sources of neutron background are well understood and accounted for when claiming a discovery or reporting limits on the WIMP-nucleon cross section. One source of neutrons that is not well understood results from cosmogenic muon interactions in the material surrounding a detector. The Neutron Multiplicity Meter in the Soudan cavern is a gadolinium-doped water Cherenkov detector capable of detecting high multiplicity neutron showers resulting from fast neutrons incident on a lead target. This measurement is the first such measurement obtained without a liquid scintillator detector medium; muon and neutron spallation is media-dependent, and because neutron shield technology for dark matter detectors is moving towards water, this is an important measurement. The integrated fast neutron flux in the Soudan cavern is reported as a linear function of the power, alpha, of the neutron angular distribution with the zenith angle: F = 4.8x10-9 +/- 3.5x10-10 + (5.4x10-10 +/- 1.5x10-10)alpha. Technological studies of neutron detection with gadolinium-doped water are also reported here. The neutron detection efficiency of a cylindrical 3.5 kL detector is measured at 70% for neutrons in the center of the detector. In addition, other improvements to water Cherenkov technology are explored, namely the addition of water-soluble wavelength-shifting chemicals. The wavelength-shifting chemical 4-Methylumbelliferone has been shown here to increase the measured light output of Cherenkov radiation resulting from neutron capture showers by a factor of 1.7.

  19. EMMNet: sensor networking for electricity meter monitoring.

    PubMed

    Lin, Zhi-Ting; Zheng, Jie; Ji, Yu-Sheng; Zhao, Bao-Hua; Qu, Yu-Gui; Huang, Xu-Dong; Jiang, Xiu-Fang

    2010-01-01

    Smart sensors are emerging as a promising technology for a large number of application domains. This paper presents a collection of requirements and guidelines that serve as a basis for a general smart sensor architecture to monitor electricity meters. It also presents an electricity meter monitoring network, named EMMNet, comprised of data collectors, data concentrators, hand-held devices, a centralized server, and clients. EMMNet provides long-distance communication capabilities, which make it suitable suitable for complex urban environments. In addition, the operational cost of EMMNet is low, compared with other existing remote meter monitoring systems based on GPRS. A new dynamic tree protocol based on the application requirements which can significantly improve the reliability of the network is also proposed. We are currently conducting tests on five networks and investigating network problems for further improvements. Evaluation results indicate that EMMNet enhances the efficiency and accuracy in the reading, recording, and calibration of electricity meters.

  20. How to Use Metered-Dose Inhalers

    MedlinePlus

    ... inhaler the right way so that the full dose of medication reaches your lungs. You can use ... inhaler.These directions explain how to use metered-dose inhalers. If you are using a different type ...

  1. Advanced smoke meter development survey and analysis

    NASA Technical Reports Server (NTRS)

    Pitz, R. W.; Penney, C. M.; Stanforth, C. M.; Shaffernocker, W. M.

    1984-01-01

    Ideal smoke meter characteristics are determined to provide a basis for evaluation of candidate systems. Five promising techniques are analyzed in detail to evaluate compilance with the practical smoke meter requirements. Four of the smoke measurement concepts are optical methods: Modulated Transmission (MODTRAN), Cross Beam Absorption Counter (CBAC), Laser Induced Incandescence (LIN), and Photoacoustic Spectroscopy (PAS). A rapid response filter instrument called a Taper Element Oscillating Microbalance (TEOM) is also evaluated. For each technique, the theoretical principles are described, the expected performance is determined, and the advantages and disadvantages are discussed The expected performance is evaluated against each of the smoke meter specifications, and the key questions for further study are given. The most promising smoke meter technique analyzed was MODTRAN, which is a variation on a direct transmission measurement. The soot-laden gas is passed through a transmission cell, and the gas pressure is modulated by a speaker.

  2. Continuous flow measurements using fixed ultrasonic meters

    USGS Publications Warehouse

    Oltmann, Rick

    1993-01-01

    USGS has or soon will be installing four continuous flow-monitoring stations in the delta that will use ultrasonic velocity meters (DVM). Funding for the stations has been provided by USGS, DWR, USBR, and Contra Costa Water District.

  3. EMMNet: Sensor Networking for Electricity Meter Monitoring

    PubMed Central

    Lin, Zhi-Ting; Zheng, Jie; Ji, Yu-Sheng; Zhao, Bao-Hua; Qu, Yu-Gui; Huang, Xu-Dong; Jiang, Xiu-Fang

    2010-01-01

    Smart sensors are emerging as a promising technology for a large number of application domains. This paper presents a collection of requirements and guidelines that serve as a basis for a general smart sensor architecture to monitor electricity meters. It also presents an electricity meter monitoring network, named EMMNet, comprised of data collectors, data concentrators, hand-held devices, a centralized server, and clients. EMMNet provides long-distance communication capabilities, which make it suitable suitable for complex urban environments. In addition, the operational cost of EMMNet is low, compared with other existing remote meter monitoring systems based on GPRS. A new dynamic tree protocol based on the application requirements which can significantly improve the reliability of the network is also proposed. We are currently conducting tests on five networks and investigating network problems for further improvements. Evaluation results indicate that EMMNet enhances the efficiency and accuracy in the reading, recording, and calibration of electricity meters. PMID:22163551

  4. Advanced metering techniques in the federal sector

    SciTech Connect

    Szydlowski, R.F.; Chvala, W.D. Jr.; Halverson, M.A.

    1994-12-01

    The lack of utility metering in the federal sector has hampered introduction of direct billing of individual activities at most military installations. Direct billing will produce accountability for the amount of energy used and is a positive step toward self-directed energy conservation. For many installations, automatic meter reading (AMR) is a cost-effective way to increase the number of meters while reducing labor requirements and providing energy conservation analysis capabilities. The communications technology used by some of the AMR systems provides other demand-side management (DSM) capabilities. This paper summarizes the characteristics and relative merits of several AMR/DSM technologies that may be appropriate for the federal sector. A case study of an AMR system being installed at Fort Irwin, California, describes a cost-effective two-way radio communication system used for meter reading and load control.

  5. Solid state recording current meter conversion

    USGS Publications Warehouse

    Cheng, Ralph T.; Wang, Lichen

    1985-01-01

    The authors describe the conversion of an Endeco-174 current meter to a solid-state recording current meter. A removable solid-state module was designed to fit in the space originally occupied by an 8-track tape cartridge. The module contains a CPU and 128 kilobytes of nonvolatile CMOS memory. The solid-state module communicates with any terminal or computer using an RS-232C interface at 4800 baud rate. A primary consideration for conversion was to keep modifications of the current meter to a minimum. The communication protocol was designed to emulate the Endeco tape translation unit, thus the need for a translation unit was eliminated and the original data reduction programs can be used without any modification. After conversion, the data recording section of the current meter contains no moving parts; the storage capacity of the module is equivalent to that of the original tape cartridge.

  6. The memory function of noradrenergic activity in non-REM sleep.

    PubMed

    Gais, Steffen; Rasch, Björn; Dahmen, Johannes C; Sara, Susan; Born, Jan

    2011-09-01

    There is a long-standing assumption that low noradrenergic activity during sleep reflects mainly the low arousal during this brain state. Nevertheless, recent research has demonstrated that the locus coeruleus, which is the main source of cortical noradrenaline, displays discrete periods of intense firing during non-REM sleep, without any signs of awakening. This transient locus coeruleus activation during sleep seems to occur in response to preceding learning-related episodes. In the present study, we manipulate noradrenergic activity during sleep in humans with either the α2-autoreceptor agonist clonidine or the noradrenaline reuptake inhibitor reboxetine. We show that reducing noradrenergic activity during sleep, but not during wakefulness, impairs subsequent memory performance in an odor recognition task. Increasing noradrenergic availability during sleep, in contrast, enhances memory retention. We conclude that noradrenergic activity during non-REM sleep interacts with other sleep-related mechanisms to functionally contribute to off-line memory consolidation.

  7. Non-rapid eye movement sleep characteristics in idiopathic REM sleep behavior disorder.

    PubMed

    Latreille, Véronique; Carrier, Julie; Montplaisir, Jacques; Lafortune, Marjolaine; Gagnon, Jean-François

    2011-11-15

    This study investigated slow waves (SW; >75μV and <4Hz) characteristics in patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). Thirty patients with iRBD and 30 age- and sex-matched healthy subjects underwent one polysomnographic (PSG) nocturnal sleep recording. SW automatic detection was performed on F3, C3, P3, and O1 leads and SW characteristics were derived (SW density, amplitude, frequency, slope, and duration of negative and positive phases). We also compared iRBD patients and control subjects on PSG variables and delta (0.25-4.0Hz) spectral power. No between-group differences were found on PSG variables, delta spectral power, or SW characteristics. Results show no SW abnormalities in iRBD patients compared to healthy participants, which suggests similar level of synchronization of thalamo-cortical neurons during N-REM sleep.

  8. Sleep architecture and REM sleep measures in prepubertal children with attention deficit disorder with hyperactivity.

    PubMed

    Greenhill, L; Puig-Antich, J; Goetz, R; Hanlon, C; Davies, M

    1983-01-01

    A 2-night polysomnographic study of 9 rigorously assessed prepubertal children who fit Diagnostic Statistical Manual-III criteria for attention deficit disorder with hyperactivity (ADDH) and a contrast group of 11 control children is reported. Despite the fact that 57% of the ADDH group were reported to experience restless sleep on structured parental rating forms, they did not show any sleep architecture abnormalities on polysomnographic recordings when compared with the normals at baseline other than decreased rapid eye movement (REM) activity. Seven of the ADDH boys were restudied after 6 months of continuous methylphenidate therapy (mean daily dose of 34.4 +/- 14.0 mg or 1.4 +/- 0.7 mg/kg). Across and within (pre-post) group comparisons showed that methylphenidate therapy was associated with delayed sleep onset, lengthened sleep, and changes in certain REM sleep variables.

  9. Regulation of flagellar, motility and chemotaxis genes in Rhizobium leguminosarum by the VisN/R-Rem cascade.

    PubMed

    Tambalo, Dinah D; Del Bel, Kate L; Bustard, Denise E; Greenwood, Paige R; Steedman, Audrey E; Hynes, Michael F

    2010-06-01

    In this paper, we describe the regulatory roles of VisN, VisR and Rem in the expression of flagellar, motility and chemotaxis genes in Rhizobium leguminosarum biovar viciae strains VF39SM and 3841. Individual mutations in the genes encoding these proteins resulted in a loss of motility and an absence of flagella, indicating that these regulatory genes are essential for flagellar synthesis and function. Transcriptional experiments involving gusA-gene fusions in wild-type and mutant backgrounds were performed to identify the genes under VisN/R and Rem regulation. Results showed that the chemotaxis and motility genes of R. leguminosarum could be separated into two groups: one group under VisN/R-Rem regulation and another group that is independent of this regulation. VisN and VisR regulate the expression of rem, while Rem positively regulates the expression of flaA, flaB, flaC, flaD, motA, motB, che1 and mcpD. All of these genes except mcpD are located within the main motility and chemotaxis gene cluster of R. leguminosarum. Other chemotaxis and motility genes, which are found outside of the main motility gene cluster (che2 operon, flaH for VF39SM, and flaG) or are plasmid-borne (flaE and mcpC), are not part of the VisN/R-Rem regulatory cascade. In addition, all genes exhibited the same regulation pattern in 3841 and in VF39SM, except flaE and flaH. flaE is not regulated by VisN/R-Rem in 3841 but it is repressed by Rem in VF39SM. flaH is under VisN/R-Rem regulation in 3841, but not in VF39SM. A kinetics experiment demonstrated that a subset of the flagellar genes is continuously expressed in all growth phases, indicating the importance of continuous motility for R. leguminosarum under free-living conditions. On the other hand, motility is repressed under symbiotic conditions. Nodulation experiments showed that the transcriptional activators VisN and Rem are dramatically downregulated in the nodules, suggesting that the symbiotic downregulation of motility-related genes

  10. High energy neutron radiography

    SciTech Connect

    Gavron, A.; Morley, K.; Morris, C.; Seestrom, S.; Ullmann, J.; Yates, G.; Zumbro, J.

    1996-06-01

    High-energy spallation neutron sources are now being considered in the US and elsewhere as a replacement for neutron beams produced by reactors. High-energy and high intensity neutron beams, produced by unmoderated spallation sources, open potential new vistas of neutron radiography. The authors discuss the basic advantages and disadvantages of high-energy neutron radiography, and consider some experimental results obtained at the Weapons Neutron Research (WNR) facility at Los Alamos.

  11. Fission foil measurements of neutron and proton fluences in the A0015 experiment

    NASA Technical Reports Server (NTRS)

    Frank, A. L.; Benton, E. V.; Armstrong, T. W.; Colborn, B. L.

    1995-01-01

    Results are given from sets of fission foil detectors (FFD's) (Ta-181, Bi-209, Th-232, U-238) which were included in the A0015 experiment to measure combined proton/neutron fluences. Use has been made of recent FFD high energy proton calibrations for improved accuracy of response. Comparisons of track density measurements have been made with the predictions of environmental modeling based on simple 1-D (slab) geometry. At 1 g/cm(exp 2) (trailing edge) the calculations were approximately 25 percent lower than measurements; at 13 g/cm(exp 2) (Earthside) calculations were more than a factor of 2 lower. A future 3-D modeling of the experiment is needed for a more meaningful comparison. Approximate mission proton doses and neutron dose equivalents were found. At Earthside (13 g/cm(exp 2) the dose was 171 rad and dose equivalent was 82 rem. At the trailing edge (1 g/cm(exp 2) dose was 315 rad and dose equivalent was 33 rem. The proton doses are less than expected from TLD doses by 16 percent and 37 percent, respectively. These differences can be explained by uncertainties in the proton and neutron spectra and in the method used to separate proton and neutron contributions to the measurements.

  12. A Preliminary Interpretation of the First Results from the REMS Surface Pressure Measurements of the MSL Mission

    NASA Technical Reports Server (NTRS)

    Haberle, Robert M.; Gomez-Elvira, J.; dalaTorreJuarez, M.; Harri, A-M.; Hollingsworth, J. L.; Kahanapaa, H.; Kahre, M. A.; Martin-Torres, F. J.; Mischna, M.; Newman, C.; Ratfkin, S. C. R.; Renno, N.; Richardson, M. I.; Rodriquez-Manfredi, J. A.; Vasavada, A. R.; Zorzano-Mier, M-P

    2013-01-01

    The Rover Environmental Monitoring Station (REMS) on the Mars Science Laboratory (MSL) Curiosity rover consists of a suite of meteorological instruments that measure pressure, temperature (air and ground), wind (speed and direction), relative humidity, and the UV flux. A description of the instruments is described elsewhere.. Here we focus on interpreting the first 90 sols of REMS operations with a particular emphasis on the pressure data.

  13. Evidence of Subthalamic PGO-like Waves During REM Sleep in Humans: A Deep Brain Polysomnographic Study

    PubMed Central

    Fernández-Mendoza, Julio; Lozano, Beatriz; Seijo, Fernando; Santamarta-Liébana, Elena; Ramos-Platón, Maria José; Vela-Bueno, Antonio; Fernández-González, Fernando

    2009-01-01

    Study Objectives: The aim of this study was to examine whether the subthalamic nucleus (STN) plays a role in the transmission of PGO-like waves during REM sleep in humans. Design: Simultaneous recordings from deep brain electrodes to record local field potentials (LFPs), and standard polysomnography to ascertain sleep/wake states. Setting: Main Hospital, department of clinical neurophysiology sleep laboratory. Participants: 12 individuals with Parkinson's disease, with electrodes implanted in the STN; and, as a control for localization purposes, 4 cluster headache patients with electrodes implanted in the posterior hypothalamus. Interventions: All subjects underwent functional neurosurgery for implantation of deep brain stimulation electrodes. Results: Sharp, polarity-reversed LFPs were recorded within the STN during REM sleep in humans. These subthalamic PGO-like waves (2–3 Hz, 80–200 μV, and 300–500 msec) appeared during REM epochs as singlets or in clusters of 3–13 waves. During the pre-REM period, subthalamic PGO-like waves were temporally related to drops in the submental electromyogram and/or onset of muscular atonia. Clusters of PGO-like waves occurred typically before and during the bursts of rapid eye movements and were associated with an enhancement in fast (15–35 Hz) subthalamic oscillatory activity. Conclusion: Subthalamic PGO-like waves can be recorded during pre-REM and REM sleep in humans. Our data suggest that the STN may play an active role in an ascending activating network implicated in the transmission of PGO waves during REM sleep in humans. Citation: Fernández-Mendoza J; Lozano B; Seijo F; Santamarta-Liébana E; Ramos-Platón MJ; Vela-Bueno A; Fernández-González F. Evidence of subthalamic PGO-like waves during REM sleep in humans: a deep brain polysomnographic study. SLEEP 2009;32(9):1117-1126. PMID:19750916

  14. Idiopathic REM Sleep Behavior Disorder: A Report on Two Cases with Contrasting Features

    PubMed Central

    Gupta, Sriniwas; Raju, M. S. V. K.; Pawar, Alka

    2015-01-01

    REM sleep behavior disorder (RBD) is a rare parasomnia in which persons exhibit uncharacteristic violent behavior, while dreaming. Secondary RBD occurs due to some neurological conditions, psychoactive substance or psychotropic drug use. There are no case reports on idiopathic RBD in India. We report here two cases to underscore the importance of identifying the disease as behavior associated with RBD may be quite serious in nature and might lead to catastrophic consequences. PMID:26664088

  15. Lack of Effects of Pramipexole on REM Sleep Behavior Disorder in Parkinson Disease

    PubMed Central

    Kumru, Hatice; Iranzo, Alex; Carrasco, Eva; Valldeoriola, Francesc; Martí, Maria José; Santamaria, Joan; Tolosa, Eduard

    2008-01-01

    Study Objectives: REM sleep behavior disorder (RBD) is a common manifestation of Parkinson disease (PD) which is characterized by dream-enacting behaviors, unpleasant dreams, and loss of muscle atonia during REM sleep. Dopaminergic mechanisms are thought to play a role in RBD pathogenesis. To further asses such a role, we have evaluated the effect of pramipexole, a dopamine receptor agonist, on RBD features in PD patients. Setting: University hospital sleep disorder center. Participants: Eleven PD patients with untreated RBD. Interventions: Not applicable. Measurements and results: In a prospective study, 11 consecutive PD patients with untreated RBD on levodopa monotherapy were placed on pramipexole to further ameliorate their parkinsonism. The effects on RBD were evaluated before and 3 months after stable pramipexole therapy through patient and bed partner interviews and blind assessment of video-polysomnographic measures. Pramipexole improved parkinsonism in all patients. Patients and bed partners reported no significant changes in frequency and severity of the abnormal RBD related motor and vocal sleep behaviors or the frequency of unpleasant dreams. Video-polysomnography analyses showed no differences in RBD related sleep measures including tonic submental electromyographic activity, phasic submental electromyographic activity, percentage of REM sleep time spent with abnormal behaviors, and severity of the abnormal behaviors detected on the videotapes. Conclusion: In PD, pramipexole improved parkinsonism but did not modify RBD related symptoms and objective video-polysomnographic abnormalities. This observation suggests that in PD, dopamine mechanisms do not play a central role in the pathogenesis of RBD. Citation: Kumru H; Iranzo A; Carrasco E; Valldeoriola F; Martí MJ; Santamaria J; Tolosa E. Lack of effects of pramipexole on REM sleep behavior disorder in parkinson disease. SLEEP 2008;31(10):1418–1421. PMID:18853939

  16. Rapid-Eye-Movement-Sleep (REM) Associated Enhancement of Working Memory Performance after a Daytime Nap.

    PubMed

    Lau, Esther Yuet Ying; Wong, Mark Lawrence; Lau, Kristy Nga Ting; Hui, Florence Wai Ying; Tseng, Chia-huei

    2015-01-01

    The main objective was to study the impact of a daytime sleep opportunity on working memory and the mechanism behind such impact. This study adopted an experimental design in a sleep research laboratory. Eighty healthy college students (Age:17-23, 36 males) were randomized to either have a polysomnography-monitored daytime sleep opportunity (Nap-group, n=40) or stay awake (Wake-group, n=40) between the two assessment sessions. All participants completed a sleep diary and wore an actigraph-watch for 5 days before and one day after the assessment sessions. They completed the state-measurement of sleepiness and affect, in addition to a psychomotor vigilance test and a working memory task before and after the nap/wake sessions. The two groups did not differ in their sleep characteristics prior to and after the lab visit. The Nap-group had higher accuracy on the working memory task, fewer lapses on the psychomotor vigilance test and lower state-sleepiness than the Wake-group. Within the Nap-group, working memory accuracy was positively correlated with duration of rapid eye movement sleep (REM) and total sleep time during the nap. Our findings suggested that "sleep gain" during a daytime sleep opportunity had significant positive impact on working memory performance, without affecting subsequent nighttime sleep in young adult, and such impact was associated with the duration of REM. While REM abnormality has long been noted in pathological conditions (e.g. depression), which are also presented with cognitive dysfunctions (e.g. working memory deficits), this was the first evidence showing working memory enhancement associated with REM in daytime napping in college students, who likely had habitual short sleep duration but were otherwise generally healthy.

  17. Cholinergic Oculomotor Nucleus Activity Is Induced by REM Sleep Deprivation Negatively Impacting on Cognition.

    PubMed

    Santos, Patrícia Dos; Targa, Adriano D S; Noseda, Ana Carolina D; Rodrigues, Lais S; Fagotti, Juliane; Lima, Marcelo M S

    2016-09-22

    Several efforts have been made to understand the involvement of rapid eye movement (REM) sleep for cognitive processes. Consolidation or retention of recognition memories is severely disrupted by REM sleep deprivation (REMSD). In this regard, pedunculopontine tegmental nucleus (PPT) and other brainstem nuclei, such as pontine nucleus (Pn) and oculomotor nucleus (OCM), appear to be candidates to take part in this REM sleep circuitry with potential involvement in cognition. Therefore, the objective of this study was to investigate a possible association between the performance of Wistar rats in a declarative memory and PPT, Pn, and OCM activities after different periods of REMSD. We examined c-Fos and choline acetyltransferase (ChaT) expressions as indicators of neuronal activity as well as a familiarity-based memory test. The animals were distributed in groups: control, REMSD, and sleep rebound (REB). At the end of the different REMSD (24, 48, 72, and 96 h) and REB (24 h) time points, the rats were immediately tested in the object recognition test and then the brains were collected. Results indicated that OCM neurons presented an increased activity, due to ChaT-labeling associated with REMSD that negatively correlated (r = -0.32) with the cognitive performance. This suggests the existence of a cholinergic compensatory mechanism within the OCM during REMSD. We also showed that 24 h of REMSD impacted similarly in memory, compared to longer periods of REMSD. These data extend the notion that REM sleep is influenced by areas other than PPT, i.e., Pn and OCM, which could be key players in both sleep processes and cognition.

  18. Did Immanuel Kant have dementia with Lewy bodies and REM behavior disorder?

    PubMed

    Miranda, Marcelo; Slachevsky, Andrea; Garcia-Borreguero, Diego

    2010-06-01

    Immanuel Kant, one of the most brilliant minds of the XVIII century and of western philosophy, suffered from dementia in his late years. Based on the analysis of testimonies of his close friends, in this report we describe his neurological disorder which, after 8years of evolution, led to his death. His cognitive decline was strongly associated with a parasomnia compatible with a severe rapid eye movement (REM) behavior disorder (RBD) and dementia with Lewy bodies.

  19. Muscarinic and PACAP receptor interactions at pontine level in the rat: significance for REM sleep regulation.

    PubMed

    Ahnaou, A; Laporte, A M; Ballet, S; Escourrou, P; Hamon, M; Adrien, J; Bourgin, P

    2000-12-01

    Cholinergic and PACAPergic systems within the oral pontine reticular nucleus (PnO) play a critical role in REM sleep generation in rats. In this present work, we have investigated whether REM sleep enhancement induced by carbachol (a cholinergic agonist) or PACAP, depends on an interaction between muscarinic and PACAP receptors. This hypothesis was tested by recording sleep-wake cycles in freely moving rats injected into the PnO with PACAP in combination with the muscarinic receptor antagonist atropine, or with carbachol in combination with the PACAP receptor antagonist PACAP6-27. When administered alone, PACAP (3 pmol) or carbachol (110 pmol) induced an enhancement of REM sleep during 8 h (+61%, n = 8; +70%, n = 5), which was totally prevented by infusion of atropine (290 pmol) for PACAP, or of PACAP6-27 (3 pmol) for carbachol. Quantitative autoradiographic studies indicated that (i) PACAP (10-9-10-7 M) induced in the PnO an increase (+35%) of the specific binding of the muscarinic antagonist [3H]quinuclidinyl benzylate, which could be completely prevented by PACAP6-27 (IC50 = 8 x 10-8 M) and (ii) both carbachol and PACAP enhanced [35S]GTP-gamma-S binding in a concentration-dependent manner in the PnO. The maximal increase due to carbachol was significantly higher in the presence (+126%) than in the absence (+102%) of PACAP (0.1 microM). These data showed that interactions between muscarinic and PACAP receptors do exist within the PnO and play a role in the local mechanisms of REM sleep control in the rat.

  20. Detection of Northern Hemisphere Transient Baroclinic Eddies in REMS Pressure Data at Gale Crater Mars

    NASA Astrophysics Data System (ADS)

    Haberle, Robert; Kahre, Melinda A.; De la Torre, Manuel; Kass, David M.; Mars Science Laboratory Science Team

    2016-10-01

    Wintertime transient baroclinic eddies in the northern midlatitudes of Mars were identified in Viking Lander 2 (VL2, 48.3N, 134.0E) surface pressure data back in the early 1980s. Here we report the results of an analysis of REMS surface pressure data acquired by the Curiosity Rover in Gale Crater (4.5S, 137.4E) that suggests the meridional scale of these eddies is so large that the disturbances in the surface pressure fields they create extend across the equator and into the southern hemisphere. A power spectrum analysis of the seasonally detrended REMS pressure data from Ls=240-280 shows dominant periods of ~ 6 sols and ~2.2 sols (though with greatly reduced power) which are close the dominant periods of the transient eddies observed by VL2 at this season. Analysis of the surface pressure fields from the Ames Mars GCM for the same season also shows dominant periods at the grid points closest to VL2 and Gale Crater similar to those observed. In the model, the disturbances responsible for these oscillations are eastward traveling baroclinic eddies whose amplitudes are greatest at northern mid latitudes at this season, but whose meridional extent does indeed extend into the low latitudes of the southern hemisphere. REMS appears to be seeing the signature of these eddies, not only for this season but for the early fall and late winter seasons as well. While orbital images of the so called "flushing storms", which more closely correspond to the shorter period waves, show dust-lifting frontal systems that cross the equator, REMS data - even though acquired at a longitude of comparatively weak storm activity - provide the first in-situ evidence that northern hemisphere transient eddies can be detected at the surface in low latitudes of the southern hemisphere.

  1. Testosterone not associated with violent dreams or REM sleep behavior disorder in men with Parkinson's.

    PubMed

    Chou, Kelvin L; Moro-De-Casillas, Maria L; Amick, Melissa M; Borek, Leora L; Friedman, Joseph H

    2007-02-15

    We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD.

  2. From REM sleep behaviour disorder to status dissociatus: insights into the maze of states of being.

    PubMed

    Vetrugno, Roberto; Montagna, Pasquale

    2011-12-01

    Sleep is a coordinated process involving more or less simultaneous changes in sensory, motor, autonomic, hormonal, and cerebral processes. On the other hand, none of the changes occurring with sleep are invariably coupled to sleep. EEG synchrony, heat loss, sleep-related hormone secretion, and even REM-related motoneuron paralysis may occur independent of the parent state. In REM sleep behaviour disorder (RBD) the muscle tone of wakefulness intrudes into REM sleep, allowing the release of dream-enacting behaviours. Status dissociatus (SD) is a condition in which brain and mind are in disarray along the boundaries of sleep and wakefulness. The existence of such dissociated behaviours shows that they have separate neuronal control systems and indicates that the whole organization of sleep is an emergent property of the collective neuronal systems to synchronize. Insults to the brain can drastically alter the circuitries responsible for maintaining the integrity of wakefulness, NREM sleep, and REM sleep. As a consequence, the basic states of existence can become admixed and interchanged with striking disturbances of consciousness, brain electrophysiology, and the behavioural and polygraphic expression of sleep and wakefulness. The evolution of RBD into SD may result from a disarray of (brainstem) structures that orchestrate the whole brain wake-sleep conditions, but with preserved discrete systems and dissociable strategies to still place navigation in wake and sleep. Advances in the fields of genetics, neuroimaging, and behavioural neurology will expand the understanding of the mechanisms underlying the organization of the states of being along with their somatic/behavioural manifestations.

  3. REM sleep deprivation attenuates actin-binding protein cortactin: a link between sleep and hippocampal plasticity.

    PubMed

    Davis, Christopher J; Meighan, Peter C; Taishi, Ping; Krueger, James M; Harding, Joseph W; Wright, John W

    2006-06-12

    Rapid eye-movement sleep (REMS) is thought to affect synaptic plasticity. Cortactin is a cytoskeletal protein critically involved in the regulation of actin branching and stabilization including the actin backbone of dendritic spines. Hippocampal cortactin levels, phosphorylation, and processing appear to be altered during learning and long-term potentiation (LTP); consistent with a role for cortactin in the dendritic restructuring that accompanies synaptic plasticity. In this study juvenile male Sprague-Dawley rats were selectively REMS-deprived (RD) for 48 h by the flowerpot method. Cage control (CC) and large pedestal control (PC) animals were used for comparison. Animals were euthanized immediately, or 12 h, after removal from the pedestal. The hippocampus was dissected, flash-frozen, and stored for subsequent Western blot or quantitative RT-PCR analysis of cortactin. Cortactin mRNA/cDNA levels initially rose in PC and RD rats but returned to CC levels by 12 h after removal from the pedestal. Predictably cortactin protein levels were initially unchanged but were up-regulated after 12 h. The PC group had more total and tyrosine-phosphorylated cortactin protein expression than the RD and CC groups. This increase in cortactin was likely due to the exposure of the rats to the novel environment of the deprivation chambers thus triggering plasticity events. The lack of REMS, however, severely hampered cortactin protein up-regulation and phosphorylation observed in the PC group suggesting an attenuation of plasticity-related events. Thus, these data support a functional link between REMS and cytoskeletal reorganization in the hippocampus, a process that is essential for synaptic plasticity.

  4. Ultrasonic meters measure gas pipeline flow

    SciTech Connect

    1995-04-01

    New ultrasonic meters from Stork Ultrasonic Technologies, Houston are improving pipeline gas flow measurements, custody transfers, process gas flow measurements, and flare gas applications. The meters are easy to install, extremely accurate, and all feature realtime measurements. This meter (Gassonic 400) is designed for use in 8-in. to 64-in. gas pipelines and features a dual transducer device which uses the absolute digital travel time method of pulse transmission. Wide band piezoceramic transducers are used in this bi-directional, single bounce system which includes pulse verification and high-speed electronic processing by a central processing unit. Measuring values of this meter are obtained by direct digital measurement of travel time of each individual ultrasonic pulse which covers a pre-determined distance between two transducers inserted in the pipe wall. These transducers cause negligible flow restriction and absolute digital reference and excellent repeatability is possible without adjustment or re-calibration. Dozens of measurements can be processed so that average output values are updated every second during use. It is a field-programmable meter for variations in site parameters, presentation of service diagnostics, user selected velocity or quantity outputs, and has standard analog and digital interfaces. Also, it is suitable for swirl measurement or compensation. Since it relies on a reflection method, the ultrasonic meter allows easy, one-sided insertion and it is suitable for hot-tapping. This instrument is especially useful in gas blending stations, compressor control, leak detection, salt dome storage applications, pipeline balancing, and additive injection systems.

  5. Differential impact of REM sleep deprivation on cytoskeletal proteins of brain regions involved in sleep regulation.

    PubMed

    Rodríguez-Vázquez, Jennifer; Camacho-Arroyo, Ignacio; Velázquez-Moctezuma, Javier

    2012-01-01

    Rapid eye movement (REM) sleep is involved in memory consolidation, which implies synaptic plasticity. This process requires protein synthesis and the reorganization of the neural cytoskeleton. REM sleep deprivation (REMSD) has an impact on some neuronal proteins involved in synaptic plasticity, such as glutamate receptors and postsynaptic density protein 95, but its effects on cytoskeletal proteins is unknown. In this study, the effects of REMSD on the content of the cytoskeletal proteins MAP2 and TAU were analyzed. Adult female rats were submitted to selective REMSD by using the multiple platform technique. After 24, 48 or 72 h of REMSD, rats were decapitated and the following brain areas were dissected: pons, preoptic area, hippocampus and frontal cortex. Protein extraction and Western blot were performed. Results showed an increase in TAU content in the pons, preoptic area and hippocampus after 24 h of REMSD, while in the frontal cortex a significant increase in TAU content was observed after 72 h of REMSD. A TAU content decrease was observed in the hippocampus after 48 h of REMSD. Interestingly, a marked increase in TAU content was observed after 72 h of REMSD. MAP2 content only increased in the preoptic area at 24 h, and in the frontal cortex after 24 and 72 h of REMSD, without significant changes in the pons and hippocampus. These results support the idea that REM sleep plays an important role in the organization of neural cytoskeleton, and that this effect is tissue-specific.

  6. A new view of "dream enactment" in REM sleep behavior disorder.

    PubMed

    Blumberg, Mark S; Plumeau, Alan M

    2016-12-01

    Patients with REM sleep behavior disorder (RBD) exhibit increased muscle tone and exaggerated myoclonic twitching during REM sleep. In addition, violent movements of the limbs, and complex behaviors that can sometimes appear to involve the enactment of dreams, are associated with RBD. These behaviors are widely thought to result from a dysfunction involving atonia-producing neural circuitry in the brainstem, thereby unmasking cortically generated dreams. Here we scrutinize the assumptions that led to this interpretation of RBD. In particular, we challenge the assumption that motor cortex produces twitches during REM sleep, thus calling into question the related assumption that motor cortex is primarily responsible for all of the pathological movements of RBD. Moreover, motor cortex is not even necessary to produce complex behavior; for example, stimulation of some brainstem structures can produce defensive and aggressive behaviors in rats and monkeys that are strikingly similar to those reported in human patients with RBD. Accordingly, we suggest an interpretation of RBD that focuses increased attention on the brainstem as a source of the pathological movements and that considers sensory feedback from moving limbs as an important influence on the content of dream mentation.

  7. Alpha Reactivity to Complex Sounds Differs during REM Sleep and Wakefulness

    PubMed Central

    Ruby, Perrine; Blochet, Camille; Eichenlaub, Jean-Baptiste; Bertrand, Olivier; Morlet, Dominique; Bidet-Caulet, Aurélie

    2013-01-01

    We aimed at better understanding the brain mechanisms involved in the processing of alerting meaningful sounds during sleep, investigating alpha activity. During EEG acquisition, subjects were presented with a passive auditory oddball paradigm including rare complex sounds called Novels (the own first name - OWN, and an unfamiliar first name - OTHER) while they were watching a silent movie in the evening or sleeping at night. During the experimental night, the subjects’ quality of sleep was generally preserved. During wakefulness, the decrease in alpha power (8–12 Hz) induced by Novels was significantly larger for OWN than for OTHER at parietal electrodes, between 600 and 900 ms after stimulus onset. Conversely, during REM sleep, Novels induced an increase in alpha power (from 0 to 1200 ms at all electrodes), significantly larger for OWN than for OTHER at several parietal electrodes between 700 and 1200 ms after stimulus onset. These results show that complex sounds have a different effect on the alpha power during wakefulness (decrease) and during REM sleep (increase) and that OWN induce a specific effect in these two states. The increased alpha power induced by Novels during REM sleep may 1) correspond to a short and transient increase in arousal; in this case, our study provides an objective measure of the greater arousing power of OWN over OTHER, 2) indicate a cortical inhibition associated with sleep protection. These results suggest that alpha modulation could participate in the selection of stimuli to be further processed during sleep. PMID:24260331

  8. Modafinil treatment prevents REM sleep deprivation-induced brain function impairment by increasing MMP-9 expression.

    PubMed

    He, Bin; Peng, Hua; Zhao, Ying; Zhou, Hui; Zhao, Zhongxin

    2011-12-02

    Previous work showed that sleep deprivation (SD) impairs hippocampal-dependent cognitive function and synaptic plasticity, and a novel wake-promoting agent modafinil prevents SD-induced memory impairment in rat. However, the mechanisms by which modafinil prevented REM-SD-induced impairment of brain function remain poorly understood. In the present study, rats were sleep-deprived by using the modified multiple platform method and brain function was detected. The results showed that modafinil treatment prevented REM-SD-induced impairment of cognitive function. Modafinil significantly reduced the number of errors compared to placebo and upregulated synapsin I expression in the dorsal hippocampal CA3 region. A synaptic plasticity-related gene, MMP-9 expression was also upregulated in modafinil-treated rats. Importantly, downregulation of MMP-9 expression by special siRNA decreased synapsin I protein levels and synapse numbers. Therefore, we demonstrated that modafinil increased cognition function and synaptic plasticity, at least in part by increasing MMP-9 expression in REM-SD rats.

  9. REM mentation in narcoleptics and normals: an empirical test of two neurocognitive theories.

    PubMed

    Fosse, R

    2000-12-01

    This study tested the two main neurocognitive models of dreaming by using cognitive data elicited from REM sleep in normals and narcoleptics. The two models were the "activation-only" view which holds that, in the context of sleep, overall activation of the brain is sufficient for consciousness to proceed in the manner of dreaming (e.g., Antrobus, 1991; Foulkes, 1993; Vogel, 1978); and the Activation, Input source, Modulation (AIM model), which predicts that not only brain activation level but also neurochemical modulatory systems exert widespread effects upon dreaming (Hobson & McCarley, 1977; Hobson, Pace-Schott, & Stickgold, 2000). Mental activity was studied in nocturnal REM in 15 narcoleptics and 9 normal healthy persons and in REM at the onset of daytime naps and nighttime sleep (SOREM) in narcoleptics. The study was performed in the subjects' homes, using instrumental awakenings and ambulatory polysomnographic techniques, and focused upon visual vividness, mentation report length, improbable and discontinuous bizarre features, and reflective consciousness. Within each subject group, most cognitive variables tended to fluctuate in line with expected variations in circadian activation level. When comparing the cognitive variables between the two groups, reflective consciousness was clearly highest in narcoleptics, whereas improbabilities and discontinuities were lower, with mentation report length and visual vividness differing less between the groups. These findings are consistent with the AIM model of sleep mentation, but not with the activation-only model.

  10. Neurophysiological insights into the pathophysiology of REM sleep behavior disorders: a review.

    PubMed

    Nardone, Raffaele; Golaszewski, Stefan; Höller, Yvonne; Christova, Monica; Trinka, Eugen; Brigo, Francesco

    2013-07-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a clinical condition characterized by an intermittent or complete loss of muscle atonia and an increase of phasic muscular activity during REM sleep (or Stage R), leading to complex nocturnal motor behaviors. Correct and early diagnosis is important because RBD may lead to serious injuries and is a well-treatable disorder. Since the characteristic electrophysiologic finding in patients with RBD is the increased electromyographic tone during REM sleep/Stage R, simultaneous video/polysomnography recording is essential for diagnosing this parasomnia. Moreover, several neurophysiological techniques have been used to improve our knowledge and understanding of this troubling sleep disorder. We reviewed the most important studies employing quantitative electroencephalography, event-related potentials, transcranial magnetic stimulation, brainstem reflexes and cortico-muscular coherence analysis. All these neurophysiological techniques have proven to provide a valuable tool to gain insight into the pathophysiological mechanisms underlying RBD. The review concludes with a brief discussion on the possible future implications for improving therapeutic approaches.

  11. Evidence that Neurons of the Sublaterodorsal Tegmental Nucleus Triggering Paradoxical (REM) Sleep Are Glutamatergic

    PubMed Central

    Clément, Olivier; Sapin, Emilie; Bérod, Anne; Fort, Patrice; Luppi, Pierre-Hervé

    2011-01-01

    Study Objectives: To determine whether sublaterodorsal tegmental nucleus (SLD) neurons triggering paradoxical (REM) sleep (PS) are glutamatergic. Design: Three groups of rats were used: controls, rats deprived of PS for 72 h, and rats allowed to recover for 3 h after deprivation. Brain sections were processed for double labeling combining Fos immunohistochemistry and vesicular glutamate transporter 2 (vGLUT2) in situ hybridization. Measurements and Results: The number of single Fos+ and Fos/vGLUT2+ double-labeled neurons was counted for each experimental condition. A very large number of Fos+ neurons expressing vGLUT2 mRNA specifically after PS hypersomnia was counted in the SLD. These double-labeled cells accounted for 84% of the total number of Fos+ cells. Conclusions: This finding adds further evidence to the concept that PS-on neurons of the SLD generating PS are of small size and glutamatergic in nature. By means of their descending projections to medullary and/or spinal glycinergic/GABAergic premotoneurons, they may be especially important for the induction of muscle atonia during PS, a disturbed phenomenon in narcolepsy and REM sleep behavior disorder. Citation: Clément O; Sapin E; Bérod A; Fort P; Luppi PH. Evidence that neurons of the sublaterodorsal tegmental nucleus triggering paradoxical (REM) sleep are glutamatergic. SLEEP 2011;34(4):419-423. PMID:21461384

  12. GABAA receptors are located in cholinergic terminals in the nucleus pontis oralis of the rat: implications for REM sleep control.

    PubMed

    Liang, Chang-Lin; Marks, Gerald A

    2014-01-16

    The oral pontine reticular formation (PnO) of rat is one region identified in the brainstem as a rapid eye movement (REM) sleep induction zone. Microinjection of GABA(A) receptor antagonists into PnO induces a long lasting increase in REM sleep, which is similar to that produced by cholinergic agonists. We previously showed that this REM sleep-induction can be completely blocked by a muscarinic antagonist, indicating that the REM sleep-inducing effect of GABA(A) receptor antagonism is dependent upon the local cholinergic system. Consistent with these findings, it has been reported that GABA(A) receptor antagonists microdialyzed into PnO resulted in increased levels of acetylcholine. We hypothesize that GABA(A) receptors located on cholinergic boutons in the PnO are responsible for the REM sleep induction by GABA(A) receptor antagonists through blocking GABA inhibition of acetylcholine release. Cholinergic, varicose axon fibers were studied in the PnO by immunofluorescence and confocal, laser scanning microscopy. Immunoreactive cholinergic boutons were found to be colocalized with GABA(A) receptor subunit protein γ2. This finding implicates a specific subtype and location of GABA(A) receptors in PnO of rat in the control of REM sleep.

  13. Perception of strong-meter and weak-meter rhythms in children with spina bifida meningomyelocele.

    PubMed

    Hopyan, Talar; Schellenberg, E Glenn; Dennis, Maureen

    2009-07-01

    Neurodevelopmental disorders such as spina bifida meningomyelocele (SBM) are often associated with dysrhythmic movement. We studied rhythm discrimination in 21 children with SBM and in 21 age-matched controls, with the research question being whether both groups showed a strong-meter advantage whereby rhythm discrimination is better for rhythms with a strong-meter, in which onsets of longer intervals occurred on the beat, than those with a weak-meter, in which onsets of longer intervals occurred off the beat. Compared to controls, the SBM group was less able to discriminate strong-meter rhythms, although they performed comparably in discriminating weak-meter rhythms. The attenuated strong-meter advantage in children with SBM shows that their rhythm deficits occur at the level of both perception and action, and may represent a central processing disruption of the brain mechanisms for rhythm.

  14. Perception of strong-meter and weak-meter rhythms in children with spina bifida meningomyelocele

    PubMed Central

    HOPYAN, TALAR; SCHELLENBERG, E. GLENN; DENNIS, MAUREEN

    2011-01-01

    Neurodevelopmental disorders such as spina bifida meningomyelocele (SBM) are often associated with dysrhythmic movement. We studied rhythm discrimination in 21 children with SBM and in 21 age-matched controls, with the research question being whether both groups showed a strong-meter advantage whereby rhythm discrimination is better for rhythms with a strong-meter, in which onsets of longer intervals occurred on the beat, than those with a weak-meter, in which onsets of longer intervals occurred off the beat. Compared to controls, the SBM group was less able to discriminate strong-meter rhythms, although they performed comparably in discriminating weak-meter rhythms. The attenuated strong-meter advantage in children with SBM shows that their rhythm deficits occur at the level of both perception and action, and may represent a central processing disruption of the brain mechanisms for rhythm. PMID:19573270

  15. NEUTRON COUNTER

    DOEpatents

    Curtis, C.D.; Carlson, R.L.; Tubinis, M.P.

    1958-07-29

    An ionization chamber instrument is described for cylindrical electrodes with an ionizing gag filling the channber. The inner electrode is held in place by a hermetic insulating seal at one end of the outer electrode, the other end of the outer electrode being closed by a gas filling tube. The outer surface of the inner electrode is coated with an active material which is responsive to neutron bombardment, such as uranium235 or boron-10, to produce ionizing radiations in the gas. The transverse cross sectional area of the inner electrode is small in relation to that of the channber whereby substantially all of the radiations are directed toward the outer electrode.

  16. NEUTRON SOURCE

    DOEpatents

    Reardon, W.A.; Lennox, D.H.; Nobles, R.G.

    1959-01-13

    A neutron source of the antimony--beryllium type is presented. The source is comprised of a solid mass of beryllium having a cylindrical recess extending therein and a cylinder containing antimony-124 slidably disposed within the cylindrical recess. The antimony cylinder is encased in aluminum. A berylliunn plug is removably inserted in the open end of the cylindrical recess to completely enclose the antimony cylinder in bsryllium. The plug and antimony cylinder are each provided with a stud on their upper ends to facilitate handling remotely.

  17. REM sleep deprivation induces changes of down regulatory antagonist modulator (DREAM) expression in the ventrobasal thalamic nuclei of sprague-dawley rats.

    PubMed

    Siran, Rosfaiizah; Ahmad, Asma Hayati; Abdul Aziz, Che Badariah; Ismail, Zalina

    2014-12-01

    REM sleep is a crucial component of sleep. Animal studies indicate that rapid eye movement (REM) sleep deprivation elicits changes in gene expression. Down regulatory antagonist modulator (DREAM) is a protein which downregulates other gene transcriptions by binding to the downstream response element site. The aim of this study is to examine the effect of REM sleep deprivation on DREAM expression in ventrobasal thalamic nuclei (VB) of rats. Seventy-two male Sprague-Dawley rats were divided into four major groups consisting of free-moving control rats (FMC) (n = 18), 72-h REM sleep-deprived rats (REMsd) (n = 18), 72-h REM sleep-deprived rats with 72-h sleep recovery (RG) (n = 18), and tank control rats (TC) (n = 18). REM sleep deprivation was elicited using the inverted flower pot technique. DREAM expression was examined in VB by immunohistochemical, Western blot, and quantitative real-time polymerase chain reaction (qRT-PCR) studies. The DREAM-positive neuronal cells (DPN) were decreased bilaterally in the VB of rats deprived of REM sleep as well as after sleep recovery. The nuclear DREAM extractions were increased bilaterally in animals deprived of REM sleep. The DREAM messenger RNA (mRNA) levels were decreased after sleep recovery. The results demonstrated a link between DREAM expression and REM sleep deprivation as well as sleep recovery which may indicate potential involvement of DREAM in REM sleep-induced changes in gene expression, specifically in nociceptive processing.

  18. Neutron Stars

    NASA Astrophysics Data System (ADS)

    van den Heuvel, Ed

    Radio pulsars are unique laboratories for a wide range of physics and astrophysics. Understanding how they are created, how they evolve and where we find them in the Galaxy, with or without binary companions, is highly constraining of theories of stellar and binary evolution. Pulsars' relationship with a recently discovered variety of apparently different classes of neutron stars is an interesting modern astrophysical puzzle which we consider in Part I of this review. Radio pulsars are also famous for allowing us to probe the laws of nature at a fundamental level. They act as precise cosmic clocks and, when in a binary system with a companion star, provide indispensable venues for precision tests of gravity. The different applications of radio pulsars for fundamental physics will be discussed in Part II. We finish by making mention of the newly discovered class of astrophysical objects, the Fast Radio Bursts, which may or may not be related to radio pulsars or neutron stars, but which were discovered in observations of the latter.

  19. Polar Maps of Thermal and Epithermal Neutrons

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Observations by NASA's 2001 Mars Odyssey spacecraft show views of the polar regions of Mars in thermal neutrons (top) and epithermal neutrons (bottom). In these maps, deep blue indicates a low amount of neutrons, and red indicates a high amount. Thermal neutrons are sensitive to the presence of hydrogen and the presence of carbon dioxide, in this case 'dry ice' frost. The red area in the upper right map indicates that about one meter (three feet) of carbon dioxide frost covers the surface around the north pole, as it does every Mars winter in the polar regions. An enhancement of thermal neutrons close to the south pole, seen as a light green color on the upper left map, indicates the presence of residual carbon dioxide in the south polar cap, even though the annual frost dissipated from that region during southern summer. Soil enriched with hydrogen is indicated by the deep blue colors on the epithermal maps (bottom), showing a low intensity of epithermal neutrons. The deep blue areas in the polar regions are believed to contain up to 50 percent water ice in the upper one meter (three feet) of the soil. The views shown here are of measurements made during the first three months of mapping using the neutron spectrometer instrument, part of the gamma ray spectrometer instrument suite. Topographic features are superimposed on the map for geographic reference.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson, and NASA's Johnson Space Center, Houston, operate the science instruments. The gamma-ray spectrometer was provided by the University of Arizona in collaboration with the Russian Aviation and Space Agency, which provided the high-energy neutron detector, and the Los Alamos National Laboratories, New Mexico, which provided the neutron spectrometer. Lockheed Martin Astronautics, Denver, is the prime

  20. Similar molecular determinants on Rem mediate two distinct modes of inhibition of CaV1.2 channels

    PubMed Central

    Puckerin, Akil A.; Chang, Donald D.; Subramanyam, Prakash; Colecraft, Henry M.

    2016-01-01

    ABSTRACT Rad/Rem/Rem2/Gem (RGK) proteins are Ras-like GTPases that potently inhibit all high-voltage-gated calcium (CaV1/CaV2) channels and are, thus, well-positioned to tune diverse physiological processes. Understanding how RGK proteins inhibit CaV channels is important for perspectives on their (patho)physiological roles and could advance their development and use as genetically-encoded CaV channel blockers. We previously reported that Rem can block surface CaV1.2 channels in 2 independent ways that engage distinct components of the channel complex: (1) by binding auxiliary β subunits (β-binding-dependent inhibition, or BBD); and (2) by binding the pore-forming α1C subunit N-terminus (α1C-binding-dependent inhibition, or ABD). By contrast, Gem uses only the BBD mechanism to block CaV1.2. Rem molecular determinants required for BBD CaV1.2 inhibition are the distal C-terminus and the guanine nucleotide binding G-domain which interact with the plasma membrane and CaVβ, respectively. However, Rem determinants for ABD CaV1.2 inhibition are unknown. Here, combining fluorescence resonance energy transfer, electrophysiology, systematic truncations, and Rem/Gem chimeras we found that the same Rem distal C-terminus and G-domain also mediate ABD CaV1.2 inhibition, but with different interaction partners. Rem distal C-terminus interacts with α1C N-terminus to anchor the G-domain which likely interacts with an as-yet-unidentified site. In contrast to some previous studies, neither the C-terminus of Rem nor Gem was sufficient to inhibit CaV1/CaV2 channels. The results reveal that similar molecular determinants on Rem are repurposed to initiate 2 independent mechanisms of CaV1.2 inhibition. PMID:27115600

  1. Use of Coriolis meters in gas applications

    SciTech Connect

    Patten, T.; Pawlas, G.

    1995-12-31

    Coriolis mass flowmeters provide a solution for measuring the mass flow rate of gases directly. Recent calibration data on compressed air shows that the factory water calibration is also valid on air. In addition, a Coriolis meter is fundamentally linear resulting in an accurate measurement over a wide flow range. Data are presented based on testing performed on Micro Motion 25 mm, 50 mm, and 75 mm Coriolis mass flowmeters on compressed air. Test pressures ranging between 1.7 bar (25 psia) and 100 bar (1450 psia) and mass flow rates ranging between 100:1 to 10:1, depending on the meter size. All calibration points fell with {plus_minus}2%, with a significant portion of the data within {plus_minus}5%. Data are also presented for a 6 mm meter on natural gas at 100 bar; all data are within {plus_minus}0.5%. Repeatability data are presented for a 9 mm meter calibrated on 100 bar air for calibration run times between 10 and 60 seconds. Meter repeatability improved approximately 10 times to {plus_minus}0.15% when the calibration time was 60 seconds.

  2. Diagnostic Flow Metering using Ultrasound Tomography

    NASA Astrophysics Data System (ADS)

    Chun, Sejong; Yoon, Byung-Ro; Lee, Kwang-Bock; Paik, Jong-Seung

    2010-06-01

    Flow meters, which are used for transferring water or crude oil through pipelines, require well-defined flow conditions for accurate flow rate monitoring. Even though all the installation conditions for the flow meters are satisfied, there could be unexpected flow disturbances, such as abrupt increase of upstream pressure, affecting on the performance of flow meters. To investigate any differences between measured and actual flow rates, flow velocity profiles inside the pipeline must be known. Ultrasound tomography is a means of reconstructing flow profiles from line-averaged velocities by Radon transformation. Diagnostic parameters are then extracted from the reconstructed flow profiles to give information whether the flow conditions are appropriate for accurate flow metering. In the present study, flow profiles downstream of a mass flow meter and a butterfly valve are reconstructed. Flow diagnostic parameters are defined using statistical moments such as mean value, standard deviation, skewness and kurtosis. The measured diagnostic parameters in the above-mentioned flow conditions are compared with those of fully-developed laminar and turbulent flow profiles to validate their usefulness.

  3. 20 Meter Solar Sail Analysis and Correlation

    NASA Technical Reports Server (NTRS)

    Taleghani, B. K.; Lively, P. S.; Banik, J.; Murphy, D. M.; Trautt, T. A.

    2005-01-01

    This paper describes finite element analyses and correlation studies to predict deformations and vibration modes/frequencies of a 20-meter solar sail system developed by ATK Space Systems. Under the programmatic leadership of NASA Marshall Space Flight Center's In-Space Propulsion activity, the 20-meter solar sail program objectives were to verify the design, to assess structural responses of the sail system, to implement lessons learned from a previous 10-meter quadrant system analysis and test program, and to mature solar sail technology to a technology readiness level (TRL) of 5. For this 20 meter sail system, static and ground vibration tests were conducted in NASA Glenn Research Center's 100 meter diameter vacuum chamber at Plum Brook station. Prior to testing, a preliminary analysis was performed to evaluate test conditions and to determine sensor and actuator locations. After testing was completed, an analysis of each test configuration was performed. Post-test model refinements included updated properties to account for the mass of sensors, wiring, and other components used for testing. This paper describes the development of finite element models (FEM) for sail membranes and masts in each of four quadrants at both the component and system levels, as well as an optimization procedure for the static test/analyses correlation.

  4. Magnetic fluid flow meter for gases

    SciTech Connect

    Popa, N.C.; Potencz, I.; Vekas, L.

    1994-03-01

    The paper presents the constructive details and functioning principle of an electronic volumetric flow meter for gases, which exploits the properties of magnetic fluids and has no moving mechanical components. It is a bidirectional flow meter, operating both in static and in moving conditions. The flow meter has a sensing unit, which consists of two sensors, one for differential pressure and an other for acceleration or inclination angle and of a tubular measuring element, as well as an electronic measuring system. Details are given on the hydrodynamic-electronic correction mechanism, which eliminates the Influences of inclinations and accelerations on the volumic flow signal, followed by a description of the main features of the electronic system. The experiments performed showed the possibility of metering even very small gas volumes, such as 0.1 cm{sup 3} at a flow rate of 50 cm{sup 3} /min. The metering at higher flow rate values, up to 100 m{sup 3}/h, needed only the insert of the measuring element corresponding to the requested How rate domain.

  5. Neutron matter, symmetry energy and neutron stars

    NASA Astrophysics Data System (ADS)

    Gandolfi, S.; Steiner, A. W.

    2016-01-01

    Recent progress in quantum Monte Carlo with modern nucleon-nucleon interactions have enabled the successful description of properties of light nuclei and neutron- rich matter. Of particular interest is the nuclear symmetry energy, the energy cost of creating an isospin asymmetry, and its connection to the structure of neutron stars. Combining these advances with recent observations of neutron star masses and radii gives insight into the equation of state of neutron-rich matter near and above the saturation density. In particular, neutron star radius measurements constrain the derivative of the symmetry energy.

  6. Neutron matter, symmetry energy and neutron stars

    SciTech Connect

    Stefano, Gandolfi; Steiner, Andrew W

    2016-01-01

    Recent progress in quantum Monte Carlo with modern nucleon-nucleon interactions have enabled the successful description of properties of light nuclei and neutron-rich matter. Of particular interest is the nuclear symmetry energy, the energy cost of creating an isospin asymmetry, and its connection to the structure of neutron stars. Combining these advances with recent observations of neutron star masses and radii gives insight into the equation of state of neutron-rich matter near and above the saturation density. In particular, neutron star radius measurements constrain the derivative of the symmetry energy.

  7. Borner Ball Neutron Detector

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Bonner Ball Neutron Detector measures neutron radiation. Neutrons are uncharged atomic particles that have the ability to penetrate living tissues, harming human beings in space. The Bonner Ball Neutron Detector is one of three radiation experiments during Expedition Two. The others are the Phantom Torso and Dosimetric Mapping.

  8. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

  9. NEUTRONIC REACTORS

    DOEpatents

    Wigner, E.P.; Young, G.J.

    1958-10-14

    A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

  10. NEUTRONIC REACTOR

    DOEpatents

    Stewart, H.B.

    1958-12-23

    A nuclear reactor of the type speclfically designed for the irradiation of materials is discussed. In this design a central cyllndrical core of moderating material ls surrounded by an active portlon comprlsed of an annular tank contalning fissionable material immersed ln a liquid moderator. The active portion ls ln turn surrounded by a reflector, and a well ls provided in the center of the core to accommodate the materlals to be irradiated. The over-all dimensions of the core ln at least one plane are equal to or greater than twice the effective slowing down length and equal to or less than twlce the effective diffuslon length for neutrons in the core materials.

  11. Interleukin-1 Inhibits Putative Cholinergic Neurons in Vitro and REM Sleep when Microinjected into the Rat Laterodorsal Tegmental Nucleus

    PubMed Central

    Brambilla, Dario; Barajon, Isabella; Bianchi, Susanna; Opp, Mark R.; Imeri, Luca

    2010-01-01

    Study Objectives: REM sleep is suppressed during infection, an effect mimicked by the administration of cytokines such as interleukin-1 (IL-1). In spite of this observation, brain sites and neurochemical systems mediating IL-1-induced suppression of REM sleep have not been identified. Cholinergic neurons in the brainstem laterodorsal tegmental nucleus (LDT) are part of the neuronal circuitry responsible for REM sleep generation. Since IL-1 inhibits acetylcholine synthesis and release, the aim of this study was to test the two different, but related hypotheses. We hypothesized that IL-1 inhibits LDT cholinergic neurons, and that, as a result of this inhibition, IL-1 suppresses REM sleep. Design, Measurement, and Results: To test these hypotheses, the electrophysiological activity of putative cholinergic LDT neurons was recorded in a rat brainstem slice preparation. Interleukin-1 significantly inhibited the firing rate of 76% of recorded putative cholinergic LDT neurons and reduced the amplitude of glutamatergic evoked potentials in 60% of recorded neurons. When IL-1 (1 ng) was microinjected into the LDT of freely behaving rats, REM sleep was reduced by about 50% (from 12.7% ± 1.5% of recording time [after vehicle] to 6.1% ± 1.4% following IL-1 administration) during post-injection hours 3-4. Conclusions: Results of this study support the hypothesis that IL-1 can suppress REM sleep by acting at the level of the LDT nucleus. Furthermore this effect may result from the inhibition of evoked glutamatergic responses and of spontaneous firing of putative cholinergic LDT neurons. Citation: Brambilla D; Barajon I; Bianchi S; Opp MR; Imeri L. Interleukin-1 inhibits putative cholinergic neurons in vitro and REM sleep when microinjected into the rat laterodorsal tegmental nucleus. SLEEP 2010;33(7):919-929. PMID:20614852

  12. DETECTORS AND EXPERIMENTAL METHODS: Simulation of a modified neutron detector applied in CSNS

    NASA Astrophysics Data System (ADS)

    Ma, Zhong-Jian; Wang, Qing-Bin; Wu, Qing-Biao

    2009-01-01

    We simulate the response of a modified Anderson-Braun rem counter in the energy range from thermal energy to about 10 GeV using the FLUKA code. Also, we simulate the lethargy spectrum of CSNS outside the beam dump. Traditional BF3 tube is replaced by the 3He tube, a layer of 0.6 cm lead is added outside the boron doped plastic attenuator and a sphere configuration is adopted. The simulation result shows that its response is exactly fit to H*(10) in the neutron energies between 10 keV and approximately 1 GeV, although the monitor slightly underestimates H*(10) in the energy range from thermal energy to about 10 keV. According to the characteristics of the CSNS, this modified counter increases the neutron energy response by 30% compared with the traditional monitors, and it can be applied in other kinds of stray field rich of high energy neutrons.

  13. Fast neutron dosimetry. Progress report, July 1, 1979-June 30, 1980

    SciTech Connect

    Attix, F.H.

    1980-01-01

    Progress is reported in: the development and testing of new gas mixtures more suitable for fast neutron dosimetry using the common A150-type Tissue-equivalent plastic ion chambers; comparison of photon doses determined with a graphite-walled proportional counter and with paired dosimeters irradiated by 14.8-MeV neutrons; a detector for the direct measurement of LET distributions from irradiation with fast neutrons; LET distributions from fast neutron irradiation of TE-plastic and graphite measured in a cylindrically symmetric geometry; progress in development of a tandem fast neutron and /sup 60/Co gamma ray source irradiation facility; an approach to the correlation of cellular response with lineal energy; calculated and measured HTO atmospheric dispersion rates within meters of a release site; application of cavity theory to fast neutrons; and fast neutron dosimetry by thermally stimulated currents in Al/sub 2/O/sub 3/. (GHT)

  14. Characteristics of the Neutron Irradiation Facilities of the PSI Calibration Laboratory

    SciTech Connect

    Hoedlmoser, H.; Schuler, Ch.; Butterweck, G.; Mayer, S.

    2011-12-13

    The neutron radiation fields of the Calibration Laboratory at Paul Scherrer Institute (PSI) are traceable to the national standards of the Physikalisch-Technische Bundesanstalt (PTB) in Germany. A Berthold LB6411 neutron dose rate meter for neutron radiation is used as a secondary standard. Recently, a thorough characterization of the neutron irradiation fields of the {sup 241}Am-Be and {sup 252}Cf sources by means of reference measurements and a detailed MCNPX simulation of the irradiation facility has been initiated. In this work, the characteristics of the neutron radiation fields are summarized and presented together with model equations and an uncertainty analysis. MCNPX results are shown for the {sup 241}Am-Be source. A comparison of measured and simulated data shows an excellent agreement. From the simulation, valuable information about the neutron fields like the contribution of scattered neutrons in the fields and the energy spectra could be obtained.

  15. 8-Meter UV/Optical Space Telescope

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2008-01-01

    This slide presentation proposes using the unprecedented capability of the planned Ares V launch vehicle, to place a 8 meter monolithic space telescope at the Earth-Sun L2 point. This new capability enables a new design pardigm -- simplicity. The six to eight meter class telescope with a massive high Technical Readiness Level ground observatory class monolithic primary mirror has been determined feasible. The proposed design, structural analysis, spacecraft design and shroud integration, thermal analysis, propulsion system, guidance navigation and pointing control assumptions about the avionics, and power systems, operational lifetime, and the idea of in-space servicing are reviewed.

  16. Liquid metal Flow Meter - Final Report

    SciTech Connect

    Andersen, C.; Hoogendoom, S.; Hudson, B.; Prince, J.; Teichert, K.; Wood, J.; Chase, K.

    2007-01-30

    Measuring the flow of liquid metal presents serious challenges. Current commercially-available flow meters use ultrasonic, electromagnetic, and other technologies to measure flow, but are inadequate for liquid metal flow measurement because of the high temperatures required by most liquid metals. As a result of the reactivity and high temperatures of most liquid metals, corrosion and leakage become very serious safety concerns. The purpose of this project is to develop a flow meter for Lockheed Martin that measures the flow rate of molten metal in a conduit.

  17. Average power meter for laser radiation

    NASA Astrophysics Data System (ADS)

    Shevnina, Elena I.; Maraev, Anton A.; Ishanin, Gennady G.

    2016-04-01

    Advanced metrology equipment, in particular an average power meter for laser radiation, is necessary for effective using of laser technology. In the paper we propose a measurement scheme with periodic scanning of a laser beam. The scheme is implemented in a pass-through average power meter that can perform continuous monitoring during the laser operation in pulse mode or in continuous wave mode and at the same time not to interrupt the operation. The detector used in the device is based on the thermoelastic effect in crystalline quartz as it has fast response, long-time stability of sensitivity, and almost uniform sensitivity dependence on the wavelength.

  18. Rare-earth metals (REMs) in nickel aluminide-based alloys: II. Effect of a REM on the phase composition of a multicomponent Ni3Al-based alloy

    NASA Astrophysics Data System (ADS)

    Povarova, K. B.; Drozdov, A. A.; Kazanskaya, N. K.; Morozov, A. E.; Kolobov, Yu. R.; Vershinina, T. N.; Kozlov, E. V.

    2008-10-01

    The hardening mechanisms are studied in the cast high-temperature next-generation materials that are based on the intermetallic compound Ni3Al and are low alloyed with refractory (W, Re, Mo, Cr) and reaction- and surface-active (REM, Ti, etc.) metals. The interaction of the main impurities (C, O, Si, S) with three characteristic representatives of the REM group (namely, Y, La, Ce), which can be used for alloying, is analyzed. The reported data on the behavior of some REMs in the alloys based on nickel monoaluminide NiAl are considered. The effect of the REMs on the phase compositions of real multicomponent semicommercial Ni3Al-based VKNA alloys produced by directional solidification is investigated, and the excess phases precipitating upon alloying are revealed. Alloying with refractory metals and REMs is shown to lead to the formation of nanophases that stabilize the dendritic or single-crystal structure of VKNA-type cast alloys and strengthen the interface boundaries in them.

  19. 49 CFR 192.357 - Customer meters and regulators: Installation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Customer meters and regulators: Installation. 192... Meters, Service Regulators, and Service Lines § 192.357 Customer meters and regulators: Installation. (a) Each meter and each regulator must be installed so as to minimize anticipated stresses upon...

  20. 49 CFR 192.353 - Customer meters and regulators: Location.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Customer meters and regulators: Location. 192.353... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer Meters, Service Regulators, and Service Lines § 192.353 Customer meters and regulators: Location. (a) Each meter and...

  1. 49 CFR 192.353 - Customer meters and regulators: Location.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Customer meters and regulators: Location. 192.353... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer Meters, Service Regulators, and Service Lines § 192.353 Customer meters and regulators: Location. (a) Each meter and...

  2. 39 CFR 501.15 - Computerized Meter Resetting System.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Computerized Meter Resetting System. 501.15... AND DISTRIBUTE POSTAGE EVIDENCING SYSTEMS § 501.15 Computerized Meter Resetting System. (a) Description. The Computerized Meter Resetting System (CMRS) permits customers to reset their postage meters...

  3. 49 CFR 192.357 - Customer meters and regulators: Installation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Customer meters and regulators: Installation. 192... Meters, Service Regulators, and Service Lines § 192.357 Customer meters and regulators: Installation. (a) Each meter and each regulator must be installed so as to minimize anticipated stresses upon...

  4. 49 CFR 192.359 - Customer meter installations: Operating pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Customer meter installations: Operating pressure... Meters, Service Regulators, and Service Lines § 192.359 Customer meter installations: Operating pressure. (a) A meter may not be used at a pressure that is more than 67 percent of the manufacturer's...

  5. 49 CFR 192.353 - Customer meters and regulators: Location.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Customer meters and regulators: Location. 192.353... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer Meters, Service Regulators, and Service Lines § 192.353 Customer meters and regulators: Location. (a) Each meter and...

  6. 49 CFR 192.359 - Customer meter installations: Operating pressure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Customer meter installations: Operating pressure... Meters, Service Regulators, and Service Lines § 192.359 Customer meter installations: Operating pressure. (a) A meter may not be used at a pressure that is more than 67 percent of the manufacturer's...

  7. 49 CFR 192.353 - Customer meters and regulators: Location.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Customer meters and regulators: Location. 192.353... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer Meters, Service Regulators, and Service Lines § 192.353 Customer meters and regulators: Location. (a) Each meter and...

  8. 49 CFR 192.357 - Customer meters and regulators: Installation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Customer meters and regulators: Installation. 192... Meters, Service Regulators, and Service Lines § 192.357 Customer meters and regulators: Installation. (a) Each meter and each regulator must be installed so as to minimize anticipated stresses upon...

  9. 49 CFR 192.357 - Customer meters and regulators: Installation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Customer meters and regulators: Installation. 192... Meters, Service Regulators, and Service Lines § 192.357 Customer meters and regulators: Installation. (a) Each meter and each regulator must be installed so as to minimize anticipated stresses upon...

  10. 18 CFR 367.9020 - Account 902, Meter reading expenses.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Account 902, Meter... GAS ACT Operation and Maintenance Expense Chart of Accounts § 367.9020 Account 902, Meter reading... customer meters, and determining consumption when performed by employees engaged in reading meters....

  11. 49 CFR 192.359 - Customer meter installations: Operating pressure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Customer meter installations: Operating pressure... Meters, Service Regulators, and Service Lines § 192.359 Customer meter installations: Operating pressure. (a) A meter may not be used at a pressure that is more than 67 percent of the manufacturer's...

  12. 49 CFR 192.359 - Customer meter installations: Operating pressure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Customer meter installations: Operating pressure... Meters, Service Regulators, and Service Lines § 192.359 Customer meter installations: Operating pressure. (a) A meter may not be used at a pressure that is more than 67 percent of the manufacturer's...

  13. 49 CFR 192.353 - Customer meters and regulators: Location.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Customer meters and regulators: Location. 192.353... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Customer Meters, Service Regulators, and Service Lines § 192.353 Customer meters and regulators: Location. (a) Each meter and...

  14. 39 CFR 501.15 - Computerized Meter Resetting System.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... AND DISTRIBUTE POSTAGE EVIDENCING SYSTEMS § 501.15 Computerized Meter Resetting System. (a) Description. The Computerized Meter Resetting System (CMRS) permits customers to reset their postage meters at... 39 Postal Service 1 2010-07-01 2010-07-01 false Computerized Meter Resetting System....

  15. Utilization of Neutron Bang-time CVD diamond detectors at the Z Accelerator

    NASA Astrophysics Data System (ADS)

    Chandler, Gordon; Hahn, Kelly; Ruiz, Carlos; Jones, Brent; Gomez, Matthew; Hess, Mark; Harding, Eric; Knapp, Patrick; Bur, James; Torres, Jose; Norris, Edward; Cooper, Gary; Styron, Jedediah; Moy, Ken; McKenna, Ian; Glebov, Vladimir; Fittinghoff, David; May, Mark; Snyder, Lucas

    2016-10-01

    We are utilizing Chemical Vapor Deposited (CVD) Diamond detectors at 2.3 meters on the Z accelerator to infer neutron bang-times from Magnetized Liner Inertial Fusion (MagLIF) sources yielding up to 3e12 DD neutrons and to bound the neutron time history of Deuterium Gas Puff loads producing 5e13 DD neutrons. The current implementation of the diagnostic and initial results will be shown as well as our future plans for the diagnostic. Sandia is sponsored by the U.S. DOE's NNSA under contract DE-AC04-94AL85000.

  16. Prevalence and Clinical Correlates of a Short Onset REM Period (SOREMP) during Routine PSG

    PubMed Central

    Cairns, Alyssa; Bogan, Richard

    2015-01-01

    Study Objectives: The objectives of this study were to quantify the (1) sensitivity and specificity of nocturnal PSG SOREMP (REM latency ≤ 15 min) for narcolepsy in those being evaluated for hypersomnolence and (2) prevalence and predictors of SOREMP during baseline PSG for patients being evaluated for various sleep disorders. Design: This was a retrospective analysis of a large repository of de-identified PSG and MSLT test results from 2007 to 2013. Setting and Patients: Patient records were retrieved from a repository of studies completed at a variety of sleep laboratories across the USA. Included in the analyses were 79,651 general sleep clinic patients (without an MSLT; 48% male; 72% Caucasian) and an additional 3,059 patients (31.3% male; 72% Caucasian) being evaluated for hypersomnolence (with a consecutive MSLT). Interventions: NA. Measurements and Results: For patients being evaluated for hypersomnolence, the prevalence of PSG SOREMP increased in a dose-response fashion with the number of REM onsets that occurred on a consecutive MSLT (0.5% for no MSLT SOREMPs to > 33.0% for those with 5 MSLT SOREMPs). Overall, having a PSG SOREMP was highly specific (99.5%; 95% CI: 99.1–99.7%) but not sensitive (6.7%; 95% CI: 4.7–9.2%) for narcolepsy. The prevalence of PSG SOREMP for patients in the general sleep clinic sample (i.e., not being evaluated by a consecutive MSLT) was 0.8% and was much higher in those that work night/swing shift. In adjusted models, African American race contributed to the most variance in PSG SOREMP. Conclusions: A short onset rapid eye movement (REM) latency occurs rarely in general sleep clinic samples (< 1.0%), but is highly specific for the diagnosis of narcolepsy. Although rare, the prevalence of the phenomenon is much higher than the estimated prevalence of narcolepsy and may provide a critical opportunity for practitioners to identify narcolepsy in sleep clinic patients. These data also suggest that the utility of polysomnography

  17. First Measurements of the Rover Environmental Monitoring Station (REMS) on the Mars Science Laboratory

    NASA Astrophysics Data System (ADS)

    Martín-Torres, F. J.; Zorzano-Mier, M.; Gomez-Elvira, J.

    2012-12-01

    The Rover Environmental Monitoring Station (REMS) on the Mars Science Laboratory (MSL) mission has sensors recording air and ground temperature, pressure, relative humidity, wind speed in the horizontal and vertical directions, as well as ultraviolet radiation in different bands. Typical daily REMS observations will collect 180 minutes of data from all sensors simultaneously (arranged in 5 minute hourly samples plus 60 additional minutes taken at times to be decided, daily, during the course of the mission). REMS will add significantly to the environmental record collected by prior missions through the range of simultaneous observations including water vapor; the ability to take measurements routinely through the night; the intended minimum of one Martian year of observations; and the first measurement of surface UV irradiation. The capability of multiple, consistent, and simultaneous data is essential for meaningful interpretation of near-surface processes including the characterization of soil thermal properties. The Martian atmosphere is generally transparent to solar radiation, but atmospheric dust absorbs solar radiation and heats the atmosphere, while UV radiation ionizes atmospheric gases and is harmful to any potential Martian organisms (past or present). For this reason, knowledge of the UV radiation flux at the surface of Mars is important for the understanding habitability conditions, one of the main goals of the MSL mission. Moreover UV radiation is a significant driver in the photochemistry of the atmosphere and surface. In this paper we present a first analysis of REMS measurements, the status of the different sensors and the potential of REMS for Mars environmental studies. REMS Team: C. Armiens, I. Carrasco, F. Gómez, A. Lepinette, J. Martín, J. Martínez-Frías, L. Mora, S. Navarro, V. Peinado, J. Rodríguez-Manfredi, J. Romeral, E. Sebastián, J. Torres, J. Verdasca (Centro de Astrobiología (CSIC-INTA), Carretera de Ajalvir, km. 4, 28850 Torrej

  18. Neutron field for boron neutron capture therapy

    SciTech Connect

    Kanda, K.; Kobayashi, T.

    1986-01-01

    Recently, the development of an epithermal neutron source has been required by medical doctors for deeper neutron penetrations, which is to be used for deep tumor treatment and diagnosis of metastasis. Several attempts have already been made to realize an epithermal neutron field, such as the undermoderated neutron beam, the filtered neutron beam, and the use of a fission plate. At present, these facilities can not be used for actual therapy. For the treatment of deep tumor, another method has been also proposed in normal water in the body is replaced by heavy water to attain a deeper neutron penetration. At Kyoto University's Research Reactor Institute, almost all physics problems have been settled relative to thermal neutron capture therapy that has been used for treating brain tumors and for biological experiments on malignant melanoma. Very recently feasibility studies to use heavy water have been started both theoretically and experimentally. The calculation shows the deeper penetration of neutrons as expected. Two kinds of experiments were done by using the KUR guide tube: 1. Thermal neutron penetration measurement. 2. Heavy water uptake in vitro sample. In addition to the above experiment using heavy water, the development of a new epithermal neutron source using a large fission plate is in progress, which is part of a mockup experiment of an atomic bomb field newly estimated.

  19. Comparison of current meters used for stream gaging

    USGS Publications Warehouse

    Fulford, Janice M.; Thibodeaux, Kirk G.; Kaehrle, William R.

    1994-01-01

    The U.S. Geological Survey (USGS) is field and laboratory testing the performance of several current meters used throughout the world for stream gaging. Meters tested include horizontal-axis current meters from Germany, the United Kingdom, and the People's Republic of China, and vertical-axis and electromagnetic current meters from the United States. Summarized are laboratory test results for meter repeatability, linearity, and response to oblique flow angles and preliminary field testing results. All current meters tested were found to under- and over-register velocities; errors usually increased as the velocity and angle of the flow increased. Repeatability and linearity of all meters tested were good. In the field tests, horizontal-axis meters, except for the two meters from the People's Republic of China, registered higher velocity than did the vertical-axis meters.

  20. Pedunculopontine Nucleus Gamma Band Activity-Preconscious Awareness, Waking, and REM Sleep

    PubMed Central

    Urbano, Francisco J.; D’Onofrio, Stasia M.; Luster, Brennon R.; Beck, Paige B.; Hyde, James Robert; Bisagno, Veronica; Garcia-Rill, Edgar

    2014-01-01

    The pedunculopontine nucleus (PPN) is a major component of the reticular activating system (RAS) that regulates waking and REM sleep, states of high-frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine PPN, intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD). Cortical gamma band activity participates in sensory perception, problem solving, and memory. Rather than participating in the temporal binding of sensory events as in the cortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that (1) the manifestation of gamma band activity during waking may employ a separate intracellular pathway compared to that during REM sleep, (2) neuronal calcium sensor (NCS-1) protein, which is over expressed in schizophrenia and bipolar disorder, modulates gamma band oscillations in the PPN in a concentration-dependent manner, (3) leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and (4) following our discovery of electrical coupling in the RAS, we hypothesize that there are cell clusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high-frequency activity related to waking and REM sleep by elements of the RAS. PMID:25368599

  1. REM and NREM power spectral analysis on two consecutive nights in psychophysiological and paradoxical insomnia sufferers.

    PubMed

    St-Jean, Geneviève; Turcotte, Isabelle; Pérusse, Alexandra D; Bastien, Célyne H

    2013-08-01

    The objectives of the study were to examine EEG activities using power spectral analysis (PSA) of good sleepers (GS), psychophysiological (PsyI) and paradoxical (ParI) insomnia sufferers on two consecutive nights. Participants completed three nights of PSG recordings in a sleep laboratory following a clinical evaluation. Participants were 26 PsyI, 20 ParI and 21 GS (mean age=40 years, SD=9.4). All sleep cycles of Nights 2 and 3 were retained for PSA. The absolute and relative activity in frequency bands (0.00 to 125.00 Hz) were computed at multiple frontal, central and parietal sites in REM and NREM sleep. Mixed model ANOVAs were performed with absolute and relative PSA data to assess differences between groups and nights. Over the course of the two nights, more absolute delta activity at F3, C3, and P3 was observed in ParI compared with PsyI suggesting deactivation of the left hemisphere in ParI and/or hyperactivation in PsyI. Further analysis on absolute PSA data revealed that differences between groups relate mostly to NREM. In REM, lower relative activity in slower frequency bands was found in ParI in comparison with GS and less relative theta activity was found in PsyI compared with GS implying higher activation in insomnia. In addition, between nights variability has been found in absolute powers of faster frequency bands (beta to omega). Signs of decreased cortical activity in absolute PSA in NREM combined with increased relative cortical activation in REM were found in ParI which might contribute to the misperception of sleep in ParI.

  2. Fear extinction memory consolidation requires potentiation of pontine-wave activity during REM sleep.

    PubMed

    Datta, Subimal; O'Malley, Matthew W

    2013-03-06

    Sleep plays an important role in memory consolidation within multiple memory systems including contextual fear extinction memory, but little is known about the mechanisms that underlie this process. Here, we show that fear extinction training in rats, which extinguished conditioned fear, increased both slow-wave sleep and rapid-eye movement (REM) sleep. Surprisingly, 24 h later, during memory testing, only 57% of the fear-extinguished animals retained fear extinction memory. We found that these animals exhibited an increase in phasic pontine-wave (P-wave) activity during post-training REM sleep, which was absent in the 43% of animals that failed to retain fear extinction memory. The results of this study provide evidence that brainstem activation, specifically potentiation of phasic P-wave activity, during post-training REM sleep is critical for consolidation of fear extinction memory. The results of this study also suggest that, contrary to the popular hypothesis of sleep and memory, increased sleep after training alone does not guarantee consolidation and/or retention of fear extinction memory. Rather, the potentiation of specific sleep-dependent physiological events may be a more accurate predictor for successful consolidation of fear extinction memory. Identification of this unique mechanism will significantly improve our present understanding of the cellular and molecular mechanisms that underlie the sleep-dependent regulation of emotional memory. Additionally, this discovery may also initiate development of a new, more targeted treatment method for clinical disorders of fear and anxiety in humans that is more efficacious than existing methods such as exposure therapy that incorporate only fear extinction.

  3. Pedunculopontine Nucleus Gamma Band Activity-Preconscious Awareness, Waking, and REM Sleep.

    PubMed

    Urbano, Francisco J; D'Onofrio, Stasia M; Luster, Brennon R; Beck, Paige B; Hyde, James Robert; Bisagno, Veronica; Garcia-Rill, Edgar

    2014-01-01

    The pedunculopontine nucleus (PPN) is a major component of the reticular activating system (RAS) that regulates waking and REM sleep, states of high-frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine PPN, intralaminar parafascicular nucleus (Pf), and pontine subcoeruleus nucleus dorsalis (SubCD). Cortical gamma band activity participates in sensory perception, problem solving, and memory. Rather than participating in the temporal binding of sensory events as in the cortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that (1) the manifestation of gamma band activity during waking may employ a separate intracellular pathway compared to that during REM sleep, (2) neuronal calcium sensor (NCS-1) protein, which is over expressed in schizophrenia and bipolar disorder, modulates gamma band oscillations in the PPN in a concentration-dependent manner, (3) leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and (4) following our discovery of electrical coupling in the RAS, we hypothesize that there are cell clusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high-frequency activity related to waking and REM sleep by elements of the RAS.

  4. Fear Extinction Memory Consolidation Requires Potentiation of Pontine-Wave Activity during REM Sleep

    PubMed Central

    Datta, Subimal; O'Malley, Matthew W .

    2013-01-01

    Sleep plays an important role in memory consolidation within multiple memory systems including contextual fear extinction memory, but little is known about the mechanisms that underlie this process. Here, we show that fear extinction training in rats, which extinguished conditioned fear, increased both slow-wave sleep and rapid-eye movement (REM) sleep. Surprisingly, 24 h later, during memory testing, only 57% of the fear-extinguished animals retained fear extinction memory. We found that these animals exhibited an increase in phasic pontine-wave (P-wave) activity during post-training REM sleep, which was absent in the 43% of animals that failed to retain fear extinction memory. The results of this study provide evidence that brainstem activation, specifically potentiation of phasic P-wave activity, during post-training REM sleep is critical for consolidation of fear extinction memory. The results of this study also suggest that, contrary to the popular hypothesis of sleep and memory, increased sleep after training alone does not guarantee consolidation and/or retention of fear extinction memory. Rather, the potentiation of specific sleep-dependent physiological events may be a more accurate predictor for successful consolidation of fear extinction memory. Identification of this unique mechanism will significantly improve our present understanding of the cellular and molecular mechanisms that underlie the sleep-dependent regulation of emotional memory. Additionally, this discovery may also initiate development of a new, more targeted treatment method for clinical disorders of fear and anxiety in humans that is more efficacious than existing methods such as exposure therapy that incorporate only fear extinction. PMID:23467372

  5. ER/LA Opioid Analgesics REMS: Overview of Ongoing Assessments of Its Progress and Its Impact on Health Outcomes

    PubMed Central

    Cepeda, M. Soledad; Kopper, Nathan W.; Maziere, Jean-Yves; Wedin, Gregory P.; Wallace, Laura E.

    2017-01-01

    Objective. Opioid abuse is a serious public health concern. In response, the Food and Drug Administration (FDA) determined that a risk evaluation and mitigation strategy (REMS) for extended-release and long-acting (ER/LA) opioids was necessary to ensure that the benefits of these analgesics continue to outweigh the risks. Key components of the REMS are training for prescribers through accredited continuing education (CE), and providing patient educational materials. Methods. The impact of this REMS has been assessed using diverse metrics including evaluation of prescriber and patient understanding of the risks associated with opioids; patient receipt and comprehension of the medication guide and patient counseling document; patient satisfaction with access to opioids; drug utilization and changes in prescribing patterns; and surveillance of ER/LA opioid misuse, abuse, overdose, addiction, and death. Results and Conclusions. The results of these assessments indicate that the increasing rates of opioid abuse, addiction, overdose, and death observed prior to implementation of the REMS have since leveled off or started to decline. However, these benefits cannot be attributed solely to the ER/LA opioid analgesics REMS since many other initiatives to prevent abuse occurred contemporaneously. These improvements occurred while preserving patient access to opioids as a large majority of patients surveyed expressed satisfaction with their access to opioids. PMID:27373304

  6. Memory sources associated with REM and NREM dream reports throughout the night: a new look at the data.

    PubMed

    Baylor, G W; Cavallero, C

    2001-03-15

    The data from three previously published studies on the memory sources of dreams, representing nine different moments of awakening throughout the night, are re-examined. In the original studies, elicited reports were recorded and segmented online into thematic units. The segmented reports were played back to Ss who were asked to identify memory sources or to associate to each segment. Memory sources were classified as episodic, semantic, or abstract self-references. In the meta-analysis and re-analyses reported here, the mean percentages of episodic memory sources are plotted separately for NREM and REM awakenings throughout the night. Within stages, neither NREM nor REM mean percentages differ significantly from each other, whereas between stages the mean percentage of episodic memory sources is significantly greater for NREM than for REM. Even when the correlation between report length and sleep stage is controlled by computing memory source density, the stage effect throughout the night persists for episodic memory sources. The relatively flat episodic memory curves for both NREM and REM indicate a rather constant recruitment of episodic memory sources throughout the night. No stage effect was found for strictly semantic memory sources. When semantic memory was defined generically, however, to include all non-spatio-temporal, "unmarked," information of self as well as of world, significantly more generic semantic memory sources derived from REM than from NREM reports, though not when corrected for the length of dream reports.

  7. Visual short-term memory deficits in REM sleep behaviour disorder mirror those in Parkinson’s disease

    PubMed Central

    Rolinski, Michal; Baig, Fahd; Giehl, Kathrin; Quinnell, Timothy; Zaiwalla, Zenobia; Mackay, Clare E.; Husain, Masud; Hu, Michele T. M.

    2016-01-01

    Individuals with REM sleep behaviour disorder are at significantly higher risk of developing Parkinson’s disease. Here we examined visual short-term memory deficits—long associated with Parkinson’s disease—in patients with REM sleep behaviour disorder without Parkinson’s disease using a novel task that measures recall precision. Visual short-term memory for sequentially presented coloured bars of different orientation was assessed in 21 patients with polysomnography-proven idiopathic REM sleep behaviour disorder, 26 cases with early Parkinson’s disease and 26 healthy controls. Three tasks using the same stimuli controlled for attentional filtering ability, sensorimotor and temporal decay factors. Both patients with REM sleep behaviour disorder and Parkinson’s disease demonstrated a deficit in visual short-term memory, with recall precision significantly worse than in healthy controls with no deficit observed in any of the control tasks. Importantly, the pattern of memory deficit in both patient groups was specifically explained by an increase in random responses. These results demonstrate that it is possible to detect the signature of memory impairment associated with Parkinson’s disease in individuals with REM sleep behaviour disorder, a condition associated with a high risk of developing Parkinson’s disease. The pattern of visual short-term memory deficit potentially provides a cognitive marker of ‘prodromal’ Parkinson’s disease that might be useful in tracking disease progression and for disease-modifying intervention trials. PMID:26582557

  8. Combat-related blast exposure and traumatic brain injury influence brain glucose metabolism during REM sleep in military veterans.

    PubMed

    Stocker, Ryan P J; Cieply, Marissa A; Paul, Benjamin; Khan, Hassen; Henry, Luke; Kontos, Anthony P; Germain, Anne

    2014-10-01

    Traumatic brain injury (TBI), a signature wound of Operations Enduring and Iraqi Freedom, can result from blunt head trauma or exposure to a blast/explosion. While TBI affects sleep, the neurobiological underpinnings between TBI and sleep are largely unknown. To examine the neurobiological underpinnings of this relationship in military veterans, [(18)F]-fluorodeoxyglucose positron emission tomography (FDG PET) was used to compare mTBI-related changes in relative cerebral metabolic rate of glucose (rCMRglc) during wakefulness, Rapid Eye Movement (REM) sleep, and non-REM (NREM) sleep, after adjusting for the effects of posttraumatic stress (PTS). Fourteen veterans with a history of blast exposure and/or mTBI (B/mTBI) (age 27.5±3.9) and eleven veterans with no history (No B/mTBI) (age 28.1±4.3) completed FDG PET studies during wakefulness, REM sleep, and NREM sleep. Whole-brain analyses were conducted using Statistical Parametric Mapping (SPM8). Between group comparisons revealed that B/mTBI was associated with significantly lower rCMRglc during wakefulness and REM sleep in the amygdala, hippocampus, parahippocampal gyrus, thalamus, insula, uncus, culmen, visual association cortices, and midline medial frontal cortices. These results suggest that alterations in neurobiological networks during wakefulness and REM sleep subsequent to B/mTBI exposure may contribute to chronic sleep disturbances and differ in individuals with acute symptoms.

  9. Transcriptome Analysis Reveals Altered Expression of Memory and Neurotransmission Associated Genes in the REM Sleep Deprived Rat Brain

    PubMed Central

    Narwade, Santosh C.; Mallick, Birendra N.; Deobagkar, Deepti D.

    2017-01-01

    Sleep disorders are associated with cognitive impairment. Selective rapid eye movement sleep (REMS) deprivation (REMSD) alters several physiological processes and behaviors. By employing NGS platform we carried out transcriptomic analysis in brain samples of control rats and those exposed to REMSD. The expression of genes involved in chromatin assembly, methylation, learning, memory, regulation of synaptic transmission, neuronal plasticity and neurohypophysial hormone synthesis were altered. Increased transcription of BMP4, DBH and ATP1B2 genes after REMSD supports our earlier findings and hypothesis. Alteration in the transcripts encoding histone subtypes and important players in chromatin remodeling was observed. The mRNAs which transcribe neurotransmitters such as OXT, AVP, PMCH and LNPEP and two small non-coding RNAs, namely RMRP and BC1 were down regulated. At least some of these changes are likely to regulate REMS and may participate in the consequences of REMS loss. Thus, the findings of this study have identified key epigenetic regulators and neuronal plasticity genes associated to REMS and its loss. This analysis provides a background and opens up avenues for unraveling their specific roles in the complex behavioral network particularly in relation to sustained REMS-loss associated changes. PMID:28367113

  10. Impaired off-line consolidation of motor memories after combined blockade of cholinergic receptors during REM sleep-rich sleep.

    PubMed

    Rasch, Björn; Gais, Steffen; Born, Jan

    2009-06-01

    Rapid eye movement (REM) sleep has been considered important for the consolidation of memories, particularly of procedural skills. REM sleep, in contrast to slow-wave sleep (SWS), is hallmarked by the high, wake-like activity of the neurotransmitter acetylcholine (ACh), which promotes certain synaptic plastic processes underlying the formation of memories. Here, we show in healthy young men that off-line consolidation of a motor skill during a period of late sleep with high amounts of REM sleep depends essentially on high cholinergic activity. After a 3-h sleep period during the early night to satisfy the need for SWS, subjects learned a procedural finger sequence tapping task and a declarative word-pair learning task. After learning, they received either placebo or a combination of the muscarinic receptor antagonist scopolamine (4 microg/kg bodyweight, intravenously) and the nicotinic receptor antagonist mecamylamine (5 mg, orally), and then slept for another 3 h, ie, the late nocturnal sleep period, which is dominated by REM sleep. Retrieval was tested the following evening. Combined cholinergic receptor blockade significantly impaired motor skill consolidation, whereas word-pair memory remained unaffected. Additional data show that the impairing effect of cholinergic receptor blockade is specific to sleep-dependent consolidation of motor skill and does not occur during a wake-retention interval. Taken together, these results identify high cholinergic activity during late, REM sleep-rich sleep as an essential factor promoting sleep-dependent consolidation of motor skills.

  11. Educational Electrical Appliance Power Meter and Logger

    ERIC Educational Resources Information Center

    Nunn, John

    2013-01-01

    The principles behind two different designs of inductive power meter are presented. They both make use of the microphone input of a computer which, together with a custom-written program, can record the instantaneous power of a domestic electrical appliance. The device can be built quickly and can be calibrated with reference to a known power…

  12. Performance of planter meters for cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Components and technology offerings to improve planter performance continue to increase. In particular, new row-meter parts allow units to improve what is called singulation (e.g. reducing skips and doubles) assuming the vacuum pressure is properly set. To help understand the value of all this new t...

  13. Modernization of the DFA Moisture Meter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Dried Fruit Association (DFA) Dried Fruit Moisture Tester has been the standard technique for determining moisture in dried fruit for more than 50 years. This method of testing moisture is recognized world wide and is AOAC approved. The meter applies the results of conductivity measurements and ...

  14. Meter Designs Reduce Operation Costs for Industry

    NASA Technical Reports Server (NTRS)

    2013-01-01

    Marshall Space Flight Center collaborated with Quality Monitoring and Control (QMC) of Humble, Texas, through a Space Act Agreement to design a balanced flow meter for the Space Shuttle Program. QMC founded APlus-QMC LLC to commercialize the technology, which has contributed to 100 new jobs, approximately $250,000 in yearly sales, and saved customers an estimated $10 million.

  15. DOE personnel neutron dosimetry evaluation and upgrade program

    SciTech Connect

    Faust, L.G.; Stroud, C.M.; Vallario, E.J.

    1988-10-01

    The US Department of Energy (DOE) sponsors an extensive research program to improve the methods, dosimeters, and instruments available to DOE facilities for measuring neutron dose and assessing its effects on the work force. The Total Dose Meter was recently developed for measuring in real time the adsorbed dose of mixed neutron and gamma radiation and for calculating the dose equivalent. The Field Neutron Spectrometer was developed to provide a portable instrument for determining neutron spectra in the workplace for flux-to-dose equivalent conversion and quality factor calculation. The Combination Thermoluminescence/Track Etch Dosimeter (TLD/TED) was developed to extend the effective neutron energy range of the conventional TLDs to improve detection of fast-energy neutrons. An Optically Stimulated Luminescence Dosimeter is presently being developed for application to gamma, neutron, and beta radiation. An Effective Dose Equivalent System is being developed to provide guidance in implementing the January 1987 Presidential Directive to determine effective dose equivalent. Superheated Drop Detectors are being investigated for their potential as real time neutron dosimeters. This paper includes discussions of these improvements brought about by the DOE research program. 3 refs.

  16. The Eight-meter-wavelength Transient Array (ETA)

    NASA Astrophysics Data System (ADS)

    Simonetti, J. H.; Ellingson, S. W.; Patterson, C. D.; Taylor, W.; Venugopal, V.; Cutchin, S.; Boor, Z.

    2005-12-01

    The Eight-meter-wavelength Transient Array (ETA) is a radio telescope utilizing a low-cost backend, which implements flexible, reconfigurable computing techniques. It is designed to continuously monitor nearly the entire northern sky at 29-47MHz in a search for low-frequency radio transients (short pulses) from high-energy astrophysical phenomena. This antenna array, which is currently under construction, is located in a relatively radio-quiet area in the Blue Ridge Mountains southwest of Asheville, NC, at the Pisgah Astronomical Research Institute (PARI). The array consists of 12 dual-polarization dipole antennas. The core of the array is 10 antenna stations arranged in a 16-m diameter circle with one antenna station at the center. In addition, one antenna station is situated about 50m to the north of the core and another is about 50m to the east of the core. A 26-m dish on the PARI site (about 1km from the ETA core) will be used for follow-up, added aperture, longer baselines, and additional radio frequency interference (RFI) mitigation. Preliminary observations with one test antenna station have detected the expected Galactic emission in this frequency range; ETA will be Galactic-noise limited. The ETA backend will utilize off-the-shelf components and a cluster of Field Programmable Gate Arrays (FPGAs) for detecting pulses of various lengths, dispersion measures, and directions (synthesized delay beams), while incorporating various RFI countermeasures. Potential sources of radio transients that might be observed by ETA include gamma-ray bursts (prompt emission), supernovae (prompt emission), coalescing compact-object binaries (e.g., neutron star -- neutron star, neutron star -- black hole), and exploding primordial black holes. This array should detect giant pulses from the Crab Pulsar, and possibly other pulsars. ETA is a collaboration of the Electrical and Computer Engineering Department and Physics Department at Virginia Tech, and PARI. ETA work at Virginia

  17. How does parkinsonism start? Prodromal parkinsonism motor changes in idiopathic REM sleep behaviour disorder.

    PubMed

    Postuma, R B; Lang, A E; Gagnon, J F; Pelletier, A; Montplaisir, J Y

    2012-06-01

    Parkinsonism, as a gradually progressive disorder, has a prodromal interval during which neurodegeneration has begun but cardinal manifestations have not fully developed. A systematic direct assessment of this interval has never been performed. Since patients with idiopathic REM sleep behaviour disorder are at very high risk of parkinsonism, they provide a unique opportunity to observe directly the development of parkinsonism. Patients with idiopathic REM sleep behaviour disorder in an ongoing cohort study were evaluated annually with several quantitative motor measures, including the Unified Parkinson's Disease Rating Scale, Purdue Pegboard, alternate-tap test and timed up-and-go. Patients who developed parkinsonism were identified from this cohort and matched according to age to normal controls. Their results on motor testing from the preceding years were plotted, and then assessed with regression analysis, to determine when markers first deviated from normal values. Sensitivity and specificity of quantitative motor markers for diagnosing prodromal parkinsonism were assessed. Of 78 patients, 20 developed parkinsonism. On regression analysis, the Unified Parkinson's Disease Rating Scale first intersected normal values at an estimated 4.5 years before diagnosis. Voice and face akinesia intersected earliest (estimated prodromal interval = 9.8 years), followed by rigidity (4.4 years), gait abnormalities (4.4 years) and limb bradykinesia (4.2 years). Quantitative motor tests intersected normal values at longer prodromal intervals than subjective examination (Purdue Pegboard = 8.6 years, alternate-tap = 8.2, timed up-and-go = 6.3). Using Purdue Pegboard and the alternate-tap test, parkinsonism could be detected with 71-82% sensitivity and specificity 3 years before diagnosis, whereas a Unified Parkinson's Disease Rating Scale score >4 identified prodromal parkinsonism with 88% sensitivity and 94% specificity 2 years before diagnosis. Removal of action

  18. KVP meter errors induced by plastic wrap

    SciTech Connect

    Jefferies, D.; Morris, J.W.; White, V.P. )

    1991-02-01

    The purpose of this study was to determine whether erroneous kVp meter readings, induced by plastic wrap, affected the actual kVp (output) of a dental X-ray machine. To evaluate the effect of plastic wrap on dental X-ray machine kVp meters, a radiation output device was used to measure output in mR/ma.s. An intraoral dental X-ray unit (S.S. White Model {number sign}90W) was used to make the exposures. First, the kVp meter was not covered with plastic wrap and output readings were recorded at various kVp settings with the milliamperage and time held constant. Secondly, the same kVp settings were selected before the plastic wrap was placed. Milliamperage and time were again held to the same constant. The X-ray console was then covered with plastic wrap prior to measuring the output for each kVp. The wrap possessed a static charge. This charge induced erroneous kVp meter readings. Out-put readings at the various induced kVp settings were then recorded. A kVp of 50 with no wrap present resulted in the same output as a kVp of 50 induced to read 40 or 60 kVp by the presence of wrap. Similar results were obtained at other kVp settings. This indicates that the plastic wrap influences only the kVp meter needle and not the actual kilovoltage of the X-ray machine. Dental X-ray machine operators should select kVp meter readings prior to placing plastic wrap and should not adjust initial settings if the meter is deflected later by the presence of wrap. The use of such a procedure will result in proper exposures, fewer retakes, and less patient radiation. If plastic wrap leads to consistent exposure errors, clinicians may wish to use a 0.5% sodium hypochlorite disinfectant as an alternative to the barrier technique.

  19. Neutron range spectrometer

    DOEpatents

    Manglos, Stephen H.

    1989-06-06

    A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

  20. NEUTRONIC REACTOR

    DOEpatents

    Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

    1958-09-01

    This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

  1. Spatial and reversal learning in the Morris water maze are largely resistant to six hours of REM sleep deprivation following training.

    PubMed

    Walsh, Christine M; Booth, Victoria; Poe, Gina R

    2011-07-01

    This first test of the role of REM (rapid eye movement) sleep in reversal spatial learning is also the first attempt to replicate a much cited pair of papers reporting that REM sleep deprivation impairs the consolidation of initial spatial learning in the Morris water maze. We hypothesized that REM sleep deprivation following training would impair both hippocampus-dependent spatial learning and learning a new target location within a familiar environment: reversal learning. A 6-d protocol was divided into the initial spatial learning phase (3.5 d) immediately followed by the reversal phase (2.5 d). During the 6 h following four or 12 training trials/day of initial or reversal learning phases, REM sleep was eliminated and non-REM sleep left intact using the multiple inverted flowerpot method. Contrary to our hypotheses, REM sleep deprivation during four or 12 trials/day of initial spatial or reversal learning did not affect training performance. However, some probe trial measures indicated REM sleep-deprivation-associated impairment in initial spatial learning with four trials/day and enhancement of subsequent reversal learning. In naive animals, REM sleep deprivation during normal initial spatial learning was followed by a lack of preference for the subsequent reversal platform location during the probe. Our findings contradict reports that REM sleep is essential for spatial learning in the Morris water maze and newly reveal that short periods of REM sleep deprivation do not impair concurrent reversal learning. Effects on subsequent reversal learning are consistent with the idea that REM sleep serves the consolidation of incompletely learned items.

  2. Neutron streak camera

    DOEpatents

    Wang, Ching L.

    1983-09-13

    Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.

  3. Neutron streak camera

    DOEpatents

    Wang, C.L.

    1983-09-13

    Disclosed is an apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon. 4 figs.

  4. Neutron streak camera

    DOEpatents

    Wang, C.L.

    1981-05-14

    Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.

  5. Layered semiconductor neutron detectors

    DOEpatents

    Mao, Samuel S; Perry, Dale L

    2013-12-10

    Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

  6. Organic metal neutron detector

    DOEpatents

    Butler, M.A.; Ginley, D.S.

    1984-11-21

    A device for detection of neutrons comprises: as an active neutron sensing element, a conductive organic polymer having an electrical conductivity and a cross-section for said neutrons whereby a detectable change in said conductivity is caused by impingement of said neutrons on the conductive organic polymer which is responsive to a property of said polymer which is altered by impingement of said neutrons on the polymer; and means for associating a change in said alterable property with the presence of neutrons at the location of said device.

  7. Neutronic Reactor Design to Reduce Neutron Loss

    DOEpatents

    Miles, F. T.

    1961-05-01

    A nuclear reactor construction is described in which an unmoderated layer of the fissionable material is inserted between the moderated portion of the reactor core and the core container steel wall. The wall is surrounded by successive layers of pure fertile material and moderator containing fertile material. The unmoderated layer of the fissionable material will insure that a greater portion of fast neutrons will pass through the steel wall than would thermal neutrons. Since the steel has a smaller capture cross section for the fast neutrons, greater nunnbers of neutrons will pass into the blanket, thereby increasing the over-all efficiency of the reactor. (AEC)

  8. NEUTRONIC REACTOR DESIGN TO REDUCE NEUTRON LOSS

    DOEpatents

    Mills, F.T.

    1961-05-01

    A nuclear reactor construction is described in which an unmoderated layer of the fissionable material is inserted between the moderated portion of the reactor core and the core container steel wall which is surrounded by successive layers of pure fertile material and fertile material having moderator. The unmoderated layer of the fissionable material will insure that a greater portion of fast neutrons will pass through the steel wall than would thermal neutrons. As the steel has a smaller capture cross-section for the fast neutrons, then greater numbers of the neutrons will pass into the blanket thereby increasing the over-all efficiency of the reactor.

  9. A differentiating empirical linguistic analysis of dreamer activity in reports of EEG-controlled REM-dreams and hypnagogic hallucinations.

    PubMed

    Speth, Jana; Frenzel, Clemens; Voss, Ursula

    2013-09-01

    We present Activity Analysis as a new method for the quantification of subjective reports of altered states of consciousness with regard to the indicated level of simulated motor activity. Empirical linguistic activity analysis was conducted with dream reports conceived immediately after EEG-controlled periods of hypnagogic hallucinations and REM-sleep in the sleep laboratory. Reports of REM-dreams exhibited a significantly higher level of simulated physical dreamer activity, while hypnagogic hallucinations appear to be experienced mostly from the point of passive observer. This study lays the groundwork for clinical research on the level of simulated activity in pathologically altered states of subjective experience, for example in the REM-dreams of clinically depressed patients, or in intrusions and dreams of patients diagnosed with PTSD.

  10. Overnight emotional adaptation to negative stimuli is altered by REM sleep deprivation and is correlated with intervening dream emotions.

    PubMed

    Lara-Carrasco, Jessica; Nielsen, Tore A; Solomonova, Elizaveta; Levrier, Katia; Popova, Ani

    2009-06-01

    Rapid eye movement (REM) sleep and dreaming may be implicated in cross-night adaptation to emotionally negative events. To evaluate the impact of REM sleep deprivation (REMD) and the presence of dream emotions on a possible emotional adaptation (EA) function, 35 healthy subjects randomly assigned to REMD (n = 17; mean age 26.4 +/- 4.3 years) and control (n = 18; mean age 23.7 +/- 4.4 years) groups underwent a partial REMD and control nights in the laboratory, respectively. In the evening preceding and morning following REMD, subjects rated neutral and negative pictures on scales of valence and arousal and EA scores were calculated. Subjects also rated dream emotions using the same scales and a 10-item emotions list. REMD was relatively successful in decreasing REM% on the experimental night, although a mean split procedure was applied to better differentiate subjects high and low in REM%. High and low groups differed - but in a direction contrary to expectations. Subjects high in REMD% showed greater adaptation to negative pictures on arousal ratings than did those low in REMD% (P < 0.05), even after statistically controlling sleep efficiency and awakening times. Subjects above the median on EA(valence) had less intense overall dream negativity (P < 0.005) and dream sadness (P < 0.004) than subjects below the median. A correlation between the emotional intensities of the morning dream and the morning picture ratings supports a possible emotional carry-over effect. REM sleep may enhance morning reactivity to negative emotional stimuli. Further, REM sleep and dreaming may be implicated in different dimensions of cross-night adaptation to negative emotions.

  11. Phasic bursts of the antagonistic jaw muscles during REM sleep mimic a coordinated motor pattern during mastication.

    PubMed

    Kato, T; Nakamura, N; Masuda, Y; Yoshida, A; Morimoto, T; Yamamura, K; Yamashita, S; Sato, F

    2013-02-01

    Sleep-related movement disorders are characterized by the specific phenotypes of muscle activities and movements during sleep. However, the state-specific characteristics of muscle bursts and movement during sleep are poorly understood. In this study, jaw-closing and -opening muscle electromyographic (EMG) activities and jaw movements were quantified to characterize phenotypes of motor patterns during sleep in freely moving and head-restrained guinea pigs. During non-rapid eye movement (NREM) sleep, both muscles were irregularly activated in terms of duration, activity, and intervals. During rapid eye movement (REM) sleep, clusters of phasic bursts occurred in the two muscles. Compared with NREM sleep, burst duration, activity, and intervals were less variable during REM sleep for both muscles. Although burst activity was lower during the two sleep states than during chewing, burst duration and intervals during REM sleep were distributed within a similar range to those during chewing. A trigger-averaged analysis of muscle bursts revealed that the temporal association between the bursts of the jaw-closing and -opening muscles during REM sleep was analogous to the temporal association during natural chewing. The burst characteristics of the two muscles reflected irregular patterns of jaw movements during NREM sleep and repetitive alternating bilateral movements during REM sleep. The distinct patterns of jaw muscle bursts and movements reflect state-specific regulations of the jaw motor system during sleep states. Phasic activations in the antagonistic jaw muscles during REM sleep are regulated, at least in part, by the neural networks involving masticatory pattern generation, demonstrating that waking jaw motor patterns are replayed during sleep periods.

  12. Effects of methylphenidate on the impairment of spontaneous alternation behavior in mice intermittently deprived of REM sleep.

    PubMed

    Niijima-Yaoita, Fukie; Nagasawa, Yuka; Tsuchiya, Masahiro; Arai, Yuichiro; Tadano, Takeshi; Tan-No, Koichi

    2016-11-01

    Attention deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity, and impulsivity. We have previously shown that abnormal behaviors elicited by intermittent rapid eye movement (REM) sleep deprivation stress may fulfill the profile of a model of ADHD. It is well known that the impairment of spontaneous alternation behavior (SAB) in the Y-maze indicates inattentive features of ADHD model animals. On the other hand, it has been reported that nitric oxide (NO) in the hippocampus is required for SAB. In this study, using mice, we investigated whether intermittent REM sleep deprivation stress causes changes in SAB and the expression of NO synthase (NOS) mRNA and in the levels of NO metabolites in the hippocampus. Mice were deprived of REM sleep intermittently by the small-platform method (20 h/day) for 3 days. The SAB, the level of nitrite and expression of endothelial NOS (eNOS) and inducible NOS (iNOS) mRNA in the hippocampus, but not neuronal NOS (nNOS), were significantly decreased by intermittent REM sleep deprivation stress. The decreased levels of SAB, nitrite and iNOS mRNA were significantly increased by methylphenidate treatment, which is used clinically to treat ADHD symptoms. Moreover, these improvement effects of methylphenidate on SAB and the nitrite level were decreased by the administration of selective iNOS and eNOS inhibitors. However, the eNOS inhibitor decreased both nitrate and total NOx levels of the hippocampus in saline treated intermittent REM sleep-deprived mice. These results suggest that the impairment of SAB induced by intermittent REM sleep deprivation stress may serve as a model of the inattention symptom in ADHD. Further, the ameliorating effects of methylphenidate on the impairment of SAB may be mediated through NO production mainly by iNOS in the hippocampus of mice.

  13. Influence of age on the interrelation between EEG frequency bands during NREM and REM sleep.

    PubMed

    Mann, Klaus; Röschke, Joachim

    2004-04-01

    The age-dependence of temporal interrelations between distinct frequency bands of sleep EEG was investigated in a group of 59 healthy young and middle-aged males via cross correlation analysis. Based on global evaluation throughout the entire night, a highly significant decline of the delta/theta correlation with increasing age was found. A separate analysis for non-rapid eye movement (NREM) and rapid eye movement (REM) sleep revealed different changes with aging. During NREM sleep, the correlation between the delta and theta frequency bands decreased with increasing age. In contrast, during REM sleep, a stronger correlation became obvious between the theta, alpha, and beta frequency bands with increasing age, whereas the lower frequency components were not affected. These findings indicate that aging processes seem to interact with sleep EEG rhythms in a complex manner, where most conspicuous is a disintegration of the activities in the lower frequency range, both concerning the successive sleep cycles across the night and the micro-structure of NREM sleep.

  14. [REM sleep parasomnias and degenerative diseases of the central nervous system].

    PubMed

    Janković, Slavko; Kostić, Vladimir; Susić, Veselinka

    2007-01-01

    Parasomnias are defined as unpleasant and undesirable behavioral (in the sense of action) or experiential (in the sense of sensorial or perceptive) phenomena which overwhelmingly or exclusively happen during sleep. Former attitudes that parasomnias are closely related to psychiatric derangement are abandoned and newer polysomnographic research indicates that we are dealing with a number of totally different organically defined states, most of which are easy to diagnose and even cure. The frequency of parasomnias in population is much higher than so far supposed so that they are considered among the most frequent disturbance of the CNS. Another inglorious record tightly connected to parasomnias is that they belong to the most frequently undiagnosed or misdiagnosed diseases. Clinically the most important and intriguing of the parasomnias associated with REM sleep, is REM sleep behavior disorder (RBD). In the last few decades in the field of human and animal sleep, researchers have noticed that RBD represents the omen of the more complex degenerative disorders of the central nervous system--the synucleinopathies and tauopathies. RBD can precede these disorders for decades before the florid clinical picture becomes obvious.

  15. A brainstem inflammatory lesion causing REM sleep behavior disorder and sleepwalking (parasomnia overlap disorder).

    PubMed

    Limousin, Nadège; Dehais, Caroline; Gout, Olivier; Héran, Françoise; Oudiette, Delphine; Arnulf, Isabelle

    2009-10-01

    A 40-year-old woman with no prior parasomnia developed an acute inflammatory rhombencephalitis with multiple cranial nerve palsies and cerebellar ataxia, followed by myelitis 6 months later, and by an intracranial thrombophlebitis 1 month after. Between and after these episodes, she had a persistent, mild right internuclear ophtalmoplegia, a mild cerebellar ataxia, and a severe REM sleep behavior disorder (RBD) lasting for 2 years. She talked, sang and moved nightly while asleep, and injured her son (cosleeping with her) while asleep. In addition, she walked asleep nightly. During video-polysomnography, there were two arousals during slow wave sleep without abnormal behavior, while 44% of REM sleep was without chin muscle atonia with bilateral arm and leg movements. There were small hypointensities in the right pontine tegmentum and in the right dorsal medulla on T1-weighted magnetic resonance imaging, suggesting post-inflammatory lesions that persisted between acute episodes. The RBD and sleepwalking did not improve with clonazepam, but improved with melatonin 9 mg/d. The unilateral small lesion of the pontine tegmentum could be responsible for the parasomnia overlap disorder as in other rare lesional cases.

  16. Altered functional Connectivity in Lesional Peduncular Hallucinosis with REM Sleep Behavior Disorder

    PubMed Central

    Geddes, Maiya R.; Tie, Yanmei; Gabrieli, John D. E.; McGinnis, Scott M.; Golby, Alexandra J.; Whitfield-Gabrieli, Susan

    2016-01-01

    Brainstem lesions causing peduncular hallucinosis (PH) produce vivid visual hallucinations occasionally accompanied by sleep disorders. Overlapping brainstem regions modulate visual pathways and REM sleep functions via gating of thalamocortical networks. A 66-year-old man with paroxysmal atrial fibrillation developed abrupt-onset complex visual hallucinations with preserved insight and violent dream enactment behavior. Brain MRI showed restricted diffusion in the left rostrodorsal pons suggestive of an acute ischemic infarct. REM sleep behavior disorder (RBD) was diagnosed on polysomnography. We investigated the integrity of ponto-geniculate-occipital circuits with seed-based resting-state functional connectivity MRI (rs-fcMRI) in this patient compared to 46 controls. Rs-fcMRI revealed significantly reduced functional connectivity between the lesion and lateral geniculate nuclei (LGN), and between LGN and visual association cortex compared to controls. Conversely, functional connectivity between brainstem and visual association cortex, and between visual association cortex and PFC was significantly increased in the patient. Focal damage to the left rostrodorsal pons is sufficient to cause RBD and PH in humans, suggesting an overlapping mechanism in both syndromes. This lesion produced a pattern of altered functional connectivity consistent with disrupted visual cortex connectivity via de-afferentation of thalamocortical pathways. PMID:26656284

  17. Aerosol optical depth as observed by the Mars Science Laboratory REMS UV photodiodes

    NASA Astrophysics Data System (ADS)

    Smith, Michael D.; Zorzano, María-Paz; Lemmon, Mark; Martín-Torres, Javier; Mendaza de Cal, Teresa

    2016-12-01

    Systematic observations taken by the REMS UV photodiodes on a daily basis throughout the landed Mars Science Laboratory mission provide a highly useful tool for characterizing aerosols above Gale Crater. Radiative transfer modeling is used to model the approximately 1.75 Mars Years of observations taken to date taking into account multiple scattering from aerosols and the extended field of view of the REMS UV photodiodes. The retrievals show in detail the annual cycle of aerosol optical depth, which is punctuated with numerous short timescale events of increased optical depth. Dust deposition onto the photodiodes is accounted for by comparison with aerosol optical depth derived from direct imaging of the Sun by Mastcam. The effect of dust on the photodiodes is noticeable, but does not dominate the signal. Cleaning of dust from the photodiodes was observed in the season around Ls=270°, but not during other seasons. Systematic deviations in the residuals from the retrieval fit are indicative of changes in aerosol effective particle size, with larger particles present during periods of increased optical depth. This seasonal dependence of aerosol particle size is expected as dust activity injects larger particles into the air, while larger aerosols settle out of the atmosphere more quickly leading to a smaller average particle size over time.

  18. Pramipexole in the treatment of REM sleep behaviour disorder: A critical review.

    PubMed

    Tan, Shian Ming; Wan, Yi Min

    2016-09-30

    While widely accepted as a first-line treatment for rapid eye movement sleep (REM) behaviour disorder, clonazepam (CNZP) has side effects that limit its applicability. Pramipexole is a possible alternative, but limited literature on its effectiveness exists. This review aims to summarize the available data on the use of pramipexole in REM sleep behaviour disorder. A systematic search of major databases was conducted to look for published and on-going trials. This search yielded a total of five articles, all of which are observational in nature. Factors associated with effectiveness include low doses (less than 1.5mg/day) and idiopathic rapid eye movement sleep behaviour disorder/absence of neurodegenerative disease. Overall, the evidence is inconclusive. This is due to the lack of randomised controlled trials and the challenges in interpreting polysomgraphy findings in rapid eye movement sleep behaviour disorder. Suggestions are given on how future trials evaluating pramipexole treatment in rapid eye movement sleep behaviour disorder could overcome current methodological issues in extant literature.

  19. Prodromal Parkinson's disease--using REM sleep behavior disorder as a window.

    PubMed

    Postuma, Ronald B

    2014-01-01

    REM sleep behavior disorder (RBD) is characterized by loss of REM atonia of sleep, such that patients act out the contents of their dreams. Perhaps the most important facet of idiopathic RBD is that it is a powerful prodromal marker of Parkinson's disease (PD) and other synucleinopathies. Several prospective studies have now established that patients with idiopathic RBD have up to an 80% risk of developing a defined neurodegenerative synucleinopathy. This has profound implications for understanding and treating early disease. First, the extremely high risk and long latency/time to intervene make RBD patients the ideal candidates for neuroprotective therapy against synucleinopathy. Second, RBD patients can be used as a 'test lab' to assess other potential prodromal predictors of PD, which could be applied to the general population in future large-scale screening programs. Third, assessing epidemiology of RBD allows us to study the epidemiology of PD and dementia with Lewy bodies 10-15 years earlier, reducing bias and opening new hypotheses as to the mechanism of action of selected risk factors. Finally, by prospectively observing RBD patients as they transition to full neurodegenerative synucleinopathy, one has an unprecedented window in which to directly observe evolution of PD from its prodromal stages. The evidence for RBD as a marker of prodromal PD and all these implications will be discussed.

  20. Rem-GTPase regulates cardiac myocyte L-type calcium current

    PubMed Central

    Magyar, Janos; Kiper, Carmen E.; Sievert, Gail; Cai, Weikang; Shi, Geng-Xian; Crump, Shawn M.; Li, Liren; Niederer, Steven; Smith, Nic; Andres, Douglas A.; Satin, Jonathan

    2012-01-01

    Rationale: The L-type calcium channels (LTCC) are critical for maintaining Ca2+-homeostasis. In heterologous expression studies, the RGK-class of Ras-related G-proteins regulates LTCC function; however, the physiological relevance of RGK–LTCC interactions is untested. Objective: In this report we test the hypothesis that the RGK protein, Rem, modulates native Ca2+ current (ICa,L) via LTCC in murine cardiomyocytes. Methods and Results: Rem knockout mice (Rem−/−) were engineered, and ICa,L and Ca2+-handling properties were assessed. Rem−/− ventricular cardiomyocytes displayed increased ICa,L density. ICa,L activation was shifted positive on the voltage axis, and β-adrenergic stimulation normalized this shift compared with wild-type ICa,L. Current kinetics, steady-state inactivation, and facilitation was unaffected by Rem−/−. Cell shortening was not significantly different. Increased ICa,L density in the absence of frank phenotypic differences motivated us to explore putative compensatory mechanisms. Despite the larger ICa,L density, Rem−/− cardiomyocyte Ca2+ twitch transient amplitude was significantly less than that compared with wild type. Computer simulations and immunoblot analysis suggests that relative dephosphorylation of Rem−/− LTCC can account for the paradoxical decrease of Ca2+ transients. Conclusions: This is the first demonstration that loss of an RGK protein influences ICa,L in vivo in cardiac myocytes. PMID:22854599