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Sample records for 24-hour time point

  1. Ocean tide loading effects on 24 hour GPS height estimates and resulting time series

    NASA Astrophysics Data System (ADS)

    Penna, N. T.; Stewart, M. P.

    2003-04-01

    GPS data from continuously operating GPS receivers are usually made available on a daily basis in 24 hour data files, so it is convenient for the user to adopt 24 hour data processing sessions. Time series are often then formed from the discrete 24 hour solutions, used for such applications as crustal deformation monitoring or high quality coordinate determination. When heights are estimated, ocean tide loading is a systematic error source that must be considered. Since the principal ocean tide loading effects have periods close to 12 and 24 hours respectively, it has been suggested from previous works that if models for ocean tide loading are not applied when processing GPS data as 24 hour sessions, at worst a small increase in the variance of the height time series will result. This paper further investigates the effects of ocean tide loading on 24 hour GPS height estimates and resulting time series, by considering a year of both simulated and real data from sites in Australia, at which the ocean tide loading effects differ substantially. The effect of each of the individual constituents is also considered. The role of the tropospheric delay mitigation strategy is addressed, regarding the effect on the height estimates when ocean tide loading effects are modelled or ignored.

  2. Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods.

    PubMed

    Tovey, Euan R; Liu-Brennan, Damien; Garden, Frances L; Oliver, Brian G; Perzanowski, Matthew S; Marks, Guy B

    2016-01-01

    Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

  3. Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods

    PubMed Central

    Tovey, Euan R.; Liu-Brennan, Damien; Garden, Frances L.; Oliver, Brian G.; Perzanowski, Matthew S.; Marks, Guy B.

    2016-01-01

    Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical

  4. Association between Diurnal Variation of Ozone Concentration and Stroke Occurrence: 24-Hour Time Series Study

    PubMed Central

    Han, Myung-Hoon; Yi, Hyeong-Joong; Kim, Young-Seo; Ko, Yong; Kim, Young-Soo

    2016-01-01

    Background and Purpose Increasing ozone concentrations have been known to damage human health and ecosystems. Although ozone tends to display diurnal variation, most studies have reported only on the association between daily ozone concentrations and ischemic stroke occurrence on the same day, or with a 1-day lag. We investigated the effect of the diurnal variation of ozone on ischemic stroke occurrence during the same day. Methods We included a consecutive series of 1,734 patients from January 1, 2008, to December 31, 2014, at a single tertiary hospital in Seoul, South Korea. We evaluated differences between temperature and pollutants at the time of stroke onset for each time interval and averaged those parameters across the 7-year study period. Results During the interval from 13:00 to 16:59, we found a positive association between ischemic stroke occurrence and ozone concentration relative to other time periods. Upper median ozone levels from 13:00 to 16:59 were positively correlated with ischemic stroke (odds ratio, 1.550; 95% confidence intervals, 1.220 to 1.970; P = <0.001) when compared with lower median levels. Conclusions The results show diurnal patterns of ischemic stroke occurrence based on upper and lower median ozone levels for a 24-hour period, which extends understanding of the association between stroke occurrence and environmental influences. PMID:27015421

  5. Personal best marathon time and longest training run, not anthropometry, predict performance in recreational 24-hour ultrarunners.

    PubMed

    Knechtle, Beat; Knechtle, Patrizia; Rosemann, Thomas; Lepers, Romuald

    2011-08-01

    In recent studies, a relationship between both low body fat and low thicknesses of selected skinfolds has been demonstrated for running performance of distances from 100 m to the marathon but not in ultramarathon. We investigated the association of anthropometric and training characteristics with race performance in 63 male recreational ultrarunners in a 24-hour run using bi and multivariate analysis. The athletes achieved an average distance of 146.1 (43.1) km. In the bivariate analysis, body mass (r = -0.25), the sum of 9 skinfolds (r = -0.32), the sum of upper body skinfolds (r = -0.34), body fat percentage (r = -0.32), weekly kilometers ran (r = 0.31), longest training session before the 24-hour run (r = 0.56), and personal best marathon time (r = -0.58) were related to race performance. Stepwise multiple regression showed that both the longest training session before the 24-hour run (p = 0.0013) and the personal best marathon time (p = 0.0015) had the best correlation with race performance. Performance in these 24-hour runners may be predicted (r2 = 0.46) by the following equation: Performance in a 24-hour run, km) = 234.7 + 0.481 (longest training session before the 24-hour run, km) - 0.594 (personal best marathon time, minutes). For practical applications, training variables such as volume and intensity were associated with performance but not anthropometric variables. To achieve maximum kilometers in a 24-hour run, recreational ultrarunners should have a personal best marathon time of ∼3 hours 20 minutes and complete a long training run of ∼60 km before the race, whereas anthropometric characteristics such as low body fat or low skinfold thicknesses showed no association with performance. PMID:21642857

  6. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust launches on time

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Flames sear the pristine blue sky behind the Boeing Delta II rocket carrying the Stardust spacecraft after the 4:04:15 p.m. launch from Launch Pad 17-A, Cape Canaveral Air Station. A 24- hour scrub postponed the launch from the originally scheduled date of Feb. 6. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  7. Severe community-acquired pneumonia: timely management measures in the first 24 hours.

    PubMed

    Phua, Jason; Dean, Nathan C; Guo, Qi; Kuan, Win Sen; Lim, Hui Fang; Lim, Tow Keang

    2016-01-01

    Mortality rates for severe community-acquired pneumonia (CAP) range from 17 to 48 % in published studies.In this review, we searched PubMed for relevant papers published between 1981 and June 2016 and relevant files. We explored how early and aggressive management measures, implemented within 24 hours of recognition of severe CAP and carried out both in the emergency department and in the ICU, decrease mortality in severe CAP.These measures begin with the use of severity assessment tools and the application of care bundles via clinical decision support tools. The bundles include early guideline-concordant antibiotics including macrolides, early haemodynamic support (lactate measurement, intravenous fluids, and vasopressors), and early respiratory support (high-flow nasal cannulae, lung-protective ventilation, prone positioning, and neuromuscular blockade for acute respiratory distress syndrome).While the proposed interventions appear straightforward, multiple barriers to their implementation exist. To successfully decrease mortality for severe CAP, early and close collaboration between emergency medicine and respiratory and critical care medicine teams is required. We propose a workflow incorporating these interventions. PMID:27567896

  8. Developing a Method to Test the Validity of 24 Hour Time Use Diaries Using Wearable Cameras: A Feasibility Pilot

    PubMed Central

    Kelly, Paul; Thomas, Emma; Doherty, Aiden; Harms, Teresa; Burke, Órlaith; Gershuny, Jonathan; Foster, Charlie

    2015-01-01

    Self-report time use diaries collect a continuous sequenced record of daily activities but the validity of the data they produce is uncertain. This study tests the feasibility of using wearable cameras to generate, through image prompted interview, reconstructed 'near-objective' data to assess their validity. 16 volunteers completed the Harmonised European Time Use Survey (HETUS) diary and used an Autographer wearable camera (recording images at approximately 15 second intervals) for the waking hours of the same 24-hour period. Participants then completed an interview in which visual images were used as prompts to reconstruct a record of activities for comparison with the diary record. 14 participants complied with the full collection protocol. We compared time use and number of discrete activities from the diary and camera records (using 10 classifications of activity). In terms of aggregate totals of daily time use we found no significant difference between the diary and camera data. In terms of number of discrete activities, participants reported a mean of 19.2 activities per day in the diaries, while image prompted interviews revealed 41.1 activities per day. The visualisations of the individual activity sequences reveal some potentially important differences between the two record types, which will be explored at the next project stage. This study demonstrates the feasibility of using wearable cameras to reconstruct time use through image prompted interview in order to test the concurrent validity of 24-hour activity time-use budgets. In future we need a suitably powered study to assess the validity and reliability of 24-hour time use diaries. PMID:26633807

  9. 24 Hours in a Day: A Listening Update to the Time Studies

    ERIC Educational Resources Information Center

    Janusik, Laura A.; Wolvin, Andrew D.

    2009-01-01

    Time is an important communication variable that has been impacted by new technology and changed the way people communicate. This study of communication time use by college students provides an update to earlier studies by factoring in computer and telephone use--media that have forced a multitasking approach to communication. Undergraduate…

  10. 24-hour pattern in lag time of response by firemen to calls for urgent medical aid.

    PubMed

    Brousse, Eric; Forget, Coralie; Riedel, Marc; Marlot, Michel; Mechkouri, Mohamed; Smolensky, Michael H; Touitou, Yvan; Reinberg, Alain

    2011-04-01

    The aim of the study was to assess the group 24-h pattern of lag time (LT) in response by regular and volunteer firemen (RFM and VFM) to calls for medical help (CFMH), specifically calls for out-of-hospital cardiac arrest (OHCA). LT, duration in min between a CFMH and departure of service vehicle equipped with a semiautomated defibrillator and generally staffed with four well-trained and ready-to-go FM, represents the integrated duration of several processes, each with separate reaction and decision-making times. The exact time of each CFHM (in min, h, day, month, yr) was recorded electronically, and the exact departure time from the station of the responding FM vehicle was recorded by an on-duty FM. Overall, CFMH made up 53 ± 9% (SEM) of all emergencies calls for aid. To standardize the study methods, the reported findings are based on 568 CFMH specifically regarding OHCA that occurred during the 4-yr study span (January 2005 to December 2008). CFMH exhibited a 24-h pattern with a major peak at 10:00 h (mean ± SEM: n = 9.5 ± 1.6) and major trough at 01:00 h (n = 1.3 ± 0.3; t test, p < .001). From year to year and season to season, a 24-h pattern was detected in the total of CFMH/h with two peaks (∼10:00 and ∼17:00 h) and two troughs (∼01:00 and ∼15:00 h) (analysis of variance [ANOVA], p < .01; Cosinor, p < .05 to < .003), with neither season- nor year-related differences (χ(2), p > .05). In CFMH/h pooled time series, ANOVA-detected differences between the hourly means (p < .01), and Cosinor analysis validated a 24-h rhythm (p < .002). In raw data, the longest LT, indicative of poorest performance, occurred at 05:00 h (8.8 ± 0.7 min) and the trough of LT, indicative of best performance, at 16:00 h (4.3 ± 0.8 min (t test, p < .02). 24-h patterning in LT was validated both by ANOVA of hourly means (p < .0006) and Cosinor analysis (p < .05), with longest LT ∼05:00 h and shortest LT ∼16.00 h for data of the

  11. Sex difference in the near-24-hour intrinsic period of the human circadian timing system

    PubMed Central

    Duffy, Jeanne F.; Cain, Sean W.; Chang, Anne-Marie; Phillips, Andrew J. K.; Münch, Mirjam Y.; Gronfier, Claude; Wyatt, James K.; Dijk, Derk-Jan; Czeisler, Charles A.

    2011-01-01

    The circadian rhythms of melatonin and body temperature are set to an earlier hour in women than in men, even when the women and men maintain nearly identical and consistent bedtimes and wake times. Moreover, women tend to wake up earlier than men and exhibit a greater preference for morning activities than men. Although the neurobiological mechanism underlying this sex difference in circadian alignment is unknown, multiple studies in nonhuman animals have demonstrated a sex difference in circadian period that could account for such a difference in circadian alignment between women and men. Whether a sex difference in intrinsic circadian period in humans underlies the difference in circadian alignment between men and women is unknown. We analyzed precise estimates of intrinsic circadian period collected from 157 individuals (52 women, 105 men; aged 18–74 y) studied in a month-long inpatient protocol designed to minimize confounding influences on circadian period estimation. Overall, the average intrinsic period of the melatonin and temperature rhythms in this population was very close to 24 h [24.15 ± 0.2 h (24 h 9 min ± 12 min)]. We further found that the intrinsic circadian period was significantly shorter in women [24.09 ± 0.2 h (24 h 5 min ± 12 min)] than in men [24.19 ± 0.2 h (24 h 11 min ± 12 min); P < 0.01] and that a significantly greater proportion of women have intrinsic circadian periods shorter than 24.0 h (35% vs. 14%; P < 0.01). The shorter average intrinsic circadian period observed in women may have implications for understanding sex differences in habitual sleep duration and insomnia prevalence. PMID:21536890

  12. Estimate of the time zero lung burden of depleted uranium in Persian Gulf War veterans by the 24-hour urinary excretion and exponential decay analysis.

    PubMed

    Durakovic, Asaf; Horan, Patricia; Dietz, Leonard A; Zimmerman, Isaac

    2003-08-01

    The aim of this study was to estimate the amount of depleted uranium (DU) in the respiratory system of Allied Forces Gulf War Veterans. Mass spectrometry (thermal ionization mass spectrometry) analysis of 24-hour urinary excretion of DU isotopes in five positive (238U/235U > 191.00) and six negative (238U/235U > 138.25) veterans was utilized in the mathematical estimation of the pulmonary burden at the time of exposure. A minimum value for the biological half-life of ceramic DU oxide in the lungs was derived from the Battelle report of the minimum dissolution half-time in simulated interstitial lung fluid corresponding to 3.85 years. The average DU concentration was 3.27 x 10(-5) mg per 24 hours in DU-positive veterans and 1.46 x 10(-8) mg in DU-negative veterans. The estimated lung burden was 0.34 mg in the DU-positive and 0.00015 mg in the DU-negative veterans. Our results provide evidence that the pulmonary concentration of DU at time zero can be quantitated as late as 9 years after inhalational exposure. PMID:12943033

  13. A Day in the Life of Millisecond Pulsar J1713+0747: Limits on Timing Precision Over 24 Hours and Implications for Gravitational Wave Detection

    NASA Astrophysics Data System (ADS)

    Dolch, Timothy; Bailes, M.; Bassa, C.; Bhat, R.; Bhattacharyya, B.; Champion, D.; Chatterjee, S.; Cognard, I.; Cordes, J. M.; Crowter, K.; Demorest, P.; Finn, L. S.; Fonseca, E.; Hessels, J.; Hobbs, G.; Janssen, G.; Jones, G.; Jordan, C.; Karuppusamy, R.; Keith, M.; Kramer, M.; Kraus, A.; Lam, M. T.; Lazarus, P.; Lazio, J.; Lee, K.; Levin, L.; Liu, K.; Lorimer, D.; Manchester, R. N.; McLaughlin, M.; Palliyaguru, N.; Perrodin, D.; Petroff, E.; Rajwade, K.; Rankin, J. M.; Ransom, S. M.; Rosenblum, J.; Roy, J.; Shannon, R.; Stappers, B.; Stinebring, D.; Stovall, K.; Teixeira, M.; van Leeuwen, J.; van Straten, W.; Verbiest, J.; Zhu, W.

    2014-01-01

    A 24-hour global observation of millisecond radio pulsar J1713+0747 was undertaken by the International Pulsar Timing Array (IPTA) collaboration as an effort to better quantify sources of noise in this object, which is regularly timed for the purpose of detecting gravitational waves (GWs). Given an 8-year timing RMS of 30ns, it is regarded as one of the best precision clocks in the PTA. However, sources of timing noise visible on timescales longer than the usual 20-30min biweekly observation may nonetheless be present. Data from the campaign were taken contiguously with the Parkes, Arecibo, Green Bank, GMRT, LOFAR, Effelsberg, WSRT, Lovell, and Nancay radio telescopes. The combined pulse times-of-arrival provide an estimate of the absolute noise floor, in other words, what unaccounted sources of timing noise impede an otherwise simple sqrt(N) improvement in timing precision, where N is the number of pulses in a single observing session. We present first results of specific phenomena probed on the unusual timescale of tens of hours, in particular interstellar scattering (ISS), and discuss the degree to which ISS affects precision timing. Finally, we examine single pulse information during selected portions of the observation and determine the degree to which the pulse jitter of J1713+0747 varies throughout the course of the day-long dataset.

  14. The Relationship of the Increase in the 'Time of the Earth Day,' from 18 Hours to 24 Hours, to the Increase in the Size of the Earth, Using the Laws of the Conservation of Momentum

    NASA Astrophysics Data System (ADS)

    Cimorelli, S. A.; Samuels, C.

    2010-12-01

    There are three articles, by others, which discuss the increase in the Earth's day, from 18 hours to 24 hours, over a period of time of about a billion years. One article refers to Striations in the Substructure of Coral, C.T. Scrutton, et al, 1965. Another article refers to the Laws of the Conservation of Momentum, as related to the relationship of the Earth and the Moon, the lunar tides, the reduction of the Earth year from 481 days to our present 365.25 days, and an increase in the lunar orbit time from 20 days to 28 days. The third article is based on the dates of tidal sediment deposits, tidalites, C. P. Sonett, et al, in the late 1980's. In this paper, we explain how the Earth's Day could have increased from 18 hours to 24 hours, as related to the Laws of Conservation of Momentum (L). Wherein we use the simple formulation from the Law of the Conservation of Angular Momentum, L=Iω, in which I=Moment of Inertia and ω=Angular Velocity; for which we assume the earth to be a perfect sphere, for which I=0.4MR2, where M and R are the Mass and radius of the earth, respectively. We evaluate the radius of the earth over a time period of several billion years, during which time the earth's angular momentum, L=Iω, is conserved. In this formulation, we show a growth in the size of the earth; and present a curve, using just three points in time, which indicates that the rate of growth is increasing over time. The first point is from about 4.5 billion years ago, the second point is from about 1 billion years ago, and the third point represents present day, with an average growth of about 1mm per year. Although evidence has been presented, by others, showing circumferential growth at the Red Sea and in the Atlantic Ocean, at about 1.5cm per year, total. However, no proof of reduction in the size of the Earth has been shown to occur in the Pacific, or anywhere else, including in references to subduction. Some might say that the subduction is occurring at the rim of the

  15. 24-Hour Academic Libraries: Adjusting to Change

    ERIC Educational Resources Information Center

    Bowman, Adam C.

    2013-01-01

    The purpose of this study was to explore the adaptive measures that academic libraries perform when implementing and operating a 24-hour schedule. Five in-depth interviews were conducted with current managerial-level librarians at 24-hour academic libraries. The exploratory interviews revealed similar measures for security, budgeting, employee…

  16. Associations between Diurnal 24-Hour Rhythm in Ambulatory Heart Rate Variability and the Timing and Amount of Meals during the Day Shift in Rotating Shift Workers

    PubMed Central

    Yoshizaki, Takahiro; Midorikawa, Toru; Hasegawa, Kohe; Mitani, Takeshi; Komatsu, Taiki; Togo, Fumiharu

    2014-01-01

    It has not hitherto been clarified whether there is an association between dietary behavior and circadian variation in autonomic nervous system activity among shift workers. This study examines diurnal 24-h rhythm in heart rate variability (HRV) and dietary behavior among rotating shift workers, while taking into account the sleep-wake cycle and physical activity. The subjects were 11 female and 2 male nurses or caregivers working in a rotating 2-shift system at a health care facility. All the subjects were asked to undergo 24-h electrocardiograph and step count recordings, and to record the time of each meal and the amounts of each food and beverage consumed. Coarse graining spectral analysis was used for approximately 10-min segments of HRV to derive the total power (TOT: >0.04 Hz) of the periodic components and the integrated power of periodic components in the low-frequency (LF: 0.04–0.15 Hz) and high-frequency (HF: >0.15 Hz) ranges. Then the ratio of HF power to TOT (HF nu) and the ratio of LF power to HF power (LF/HF) were calculated to assess cardiac vagal tone and cardiac sympathovagal balance, respectively. Single cosinor analysis was used to obtain 24-h period variations in both variables of HRV. Acrophases of HF nu and LF/HF expressed in time since awakening were significantly (p<0.05) delayed for subjects having breakfast at a later time after awakening. Multivariable regression analysis indicated that the timing of breakfast, the ratio of energy intake at dinner to total energy intake, and total energy intake were correlated to the acrophases of HF nu and/or LF/HF. These results suggest that the phase angle between circadian variation in cardiac autonomic nervous system activity and the sleep-wake cycle may be associated with dietary behavior in shift workers. PMID:25211024

  17. The 24-Hour Mathematical Modeling Challenge

    ERIC Educational Resources Information Center

    Galluzzo, Benjamin J.; Wendt, Theodore J.

    2015-01-01

    Across the mathematics curriculum there is a renewed emphasis on applications of mathematics and on mathematical modeling. Providing students with modeling experiences beyond the ordinary classroom setting remains a challenge, however. In this article, we describe the 24-hour Mathematical Modeling Challenge, an extracurricular event that exposes…

  18. Breast milk intake: 12 hour versus 24 hour assessment.

    PubMed

    De Carvalho, M; Pittard, W

    1982-11-01

    Letter to the editor commenting on "Clinical and field studies of human lactation: methodological considerations," by Brown et al. The point is made that in test-weighing infants to estimate breast milk intake, culture related breastfeeding practices must be studied before a 12 hour test period is used to estimate intake for a complete 24 hour period. In western cultures milk intake between 7 am and 7 pm was found to differ significantly from intake between 7 pm and 7 am, whereas in a Bangladesh study milk intake during the 2 12 hour periods was comparable. PMID:7137079

  19. Circadian Polymorphisms in Night Owls, in Bipolars, and in Non-24-Hour Sleep Cycles

    PubMed Central

    Klimecki, Walter T.; Nievergelt, Caroline M.; Rex, Katharine M.; Murray, Sarah S.; Shekhtman, Tatyana; Tranah, Gregory J.; Loving, Richard T.; Lee, Heon-Jeong; Rhee, Min Kyu; Shadan, Farhad F.; Poceta, J. Steven; Jamil, Shazia M.; Kline, Lawrence E.; Kelsoe, John R.

    2014-01-01

    People called night owls habitually have late bedtimes and late times of arising, sometimes suffering a heritable circadian disturbance called delayed sleep phase syndrome (DSPS). Those with DSPS, those with more severe progressively-late non-24-hour sleep-wake cycles, and those with bipolar disorder may share genetic tendencies for slowed or delayed circadian cycles. We searched for polymorphisms associated with DSPS in a case-control study of DSPS research participants and a separate study of Sleep Center patients undergoing polysomnography. In 45 participants, we resequenced portions of 15 circadian genes to identify unknown polymorphisms that might be associated with DSPS, non-24-hour rhythms, or bipolar comorbidities. We then genotyped single nucleotide polymorphisms (SNPs) in both larger samples, using Illumina Golden Gate assays. Associations of SNPs with the DSPS phenotype and with the morningness-eveningness parametric phenotype were computed for both samples, then combined for meta-analyses. Delayed sleep and "eveningness" were inversely associated with loci in circadian genes NFIL3 (rs2482705) and RORC (rs3828057). A group of haplotypes overlapping BHLHE40 was associated with non-24-hour sleep-wake cycles, and less robustly, with delayed sleep and bipolar disorder (e.g., rs34883305, rs34870629, rs74439275, and rs3750275 were associated with n=37, p=4.58E-09, Bonferroni p=2.95E-06). Bright light and melatonin can palliate circadian disorders, and genetics may clarify the underlying circadian photoperiodic mechanisms. After further replication and identification of the causal polymorphisms, these findings may point to future treatments for DSPS, non-24-hour rhythms, and possibly bipolar disorder or depression. PMID:25395965

  20. Physical and Mental Health of Patients Immediately After Discharge From Intensive Care Unit and 24 Hours Later

    PubMed Central

    Momennasab, Marzieh; Ghahramani, Tahereh; Yektatalab, Shahrzad; Zand, Farid

    2016-01-01

    Background: Monitoring the health status of patients discharged from intensive care units is a crucial method of service evaluation. Objectives: This study aimed to assess the physical and mental health status of patients immediately after discharge from the ICU and 24 hours later. Patients and Methods: This descriptive comparative study was conducted on 104 patients discharged from the ICUs of a referral trauma center in Shiraz, Southwest Iran. Physical parameters, including respiratory rate, need for supplemental oxygen, heart rate, blood pressure, and need for cardiac monitoring, were assessed. Hospital anxiety and depression scale (HADS) was used for mental health evaluation. The mental and physical status of patients were assessed before ICU discharge and 24 hours later; data were recorded in information forms and were analyzed using SPSS statistical software version 17. Results: At the time of discharge, the respiratory rate of 28% of the participants was more than 24 minutes, and 95.2% received supplemental oxygen. However, after 24 hours these values decreased to 10% and 21.6%, respectively. The mean heart rate and systolic blood pressure were within the normal range at both time points. Additionally, 63% of the patients had anxiety scores above 11 at both time points, reflecting high anxiety. The number of patients who reported depression increased from 58.7% at ICU discharge to 69.6% after 24 hours. Conclusions: Despite the considerable improvement in most of the patients’ physical condition in the first 24 hours after discharge from ICU, a significant number of them remain at risk for the development of adverse effects from this transition. The high prevalence of mental health disorders in these patients reveals the necessity to conduct follow-up consultations. PMID:27218059

  1. Human prolactin - 24-hour pattern with increased release during sleep.

    NASA Technical Reports Server (NTRS)

    Sassin, J. F.; Weitzman, E. D.; Kapen, S.; Frantz, A. G.

    1972-01-01

    Human prolactin was measured in plasma by radioimmunoassay at 20-minute intervals for a 24-hour period in each of six normal adults, whose sleep-wake cycles were monitored polygraphically. A marked diurnal variation in plasma concentrations was demonstrated, with highest values during sleep. Periods of episodic release occurred throughout the 24 hours.

  2. HEART RATE VARIABILITY AND 24-HOUR MINIMUM HEART RATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heart rate variability (HRV) indices based on 24-hour electrocardiograph recordings have been used in clinical research studies to assess the aggregate activity of the autonomic nervous system. While 24-hour HRV is generally considered non-invasive, use in research protocols typically involves cons...

  3. [Isolation of Mycobacterium avium complex from the "24-hour bath"].

    PubMed

    Saito, H; Murakami, K; Ishii, N; Kwon, H H

    2000-01-01

    The "24-HOUR BATH" is an apparatus which circulates the bath water, keeps it clean and warm, and makes it possible to take a bath at any time during the day or night. It consists of apparatus for cleaning (sponge or mesh filter and filter material), heating (ceramic heater), and sterilizing (UV lamp). Recently, three cases of skin disease due to M. avium infection in private homes, in which "24-HOUR BATH" water was suspected to be the source of infection, have been reported. We attempted to isolate M. avium complex from the water (32 specimens), sponge filter (29 specimens), and filter material (32 specimens) of the "24-HOUR BATH". One hundred-ml samples of bath water, and 50-ml samples of rinse from a sponge filter or filter material were centrifuged at 3000 rpm for 20 min. Sediment was suspended in distilled water and a smear was prepared, and then digested and decontaminated with 2% sodium hydroxide. The processed specimens were cultured on 2% Ogawa medium containing ofloxacin (1 microgram/ml) and ethambutol (2.5 micrograms/ml) for 8 weeks at 37 degrees C. Positive smears were 3 (9.4%), 25 (86.2%) and 25 (78.1%) specimens from the water, sponge and filter material, respectively. A few bacterial clumps were observed, especially in the sponge specimens. The number of positive culture was 5 (15.6%), 24 (82.8%) and 25 (78.1%) from the water, sponge and filter material, respectively. Among them the number of Runyon's Group III-positive cultures was 5 (100%), 22 (91.7%) and 20 (80%) in the water, sponge, and filter material specimens, respectively. In most cases, cultures were positive for both the sponge and filter material specimens. All of the Group III mycobacteria were smooth, grew at 28, 37, 42, and 45 degrees C, negative for niacin, nitrate reductase, semiquantitative catalase, urease and Tween80 hydrolysis, and positive for 68 degrees C catalase. All of the strains reacted with M. avium complex AccuProbe and M. avium AccuProbe, but none of the strains reacted

  4. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  5. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  6. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  7. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  8. 29 CFR 785.21 - Less than 24-hour duty.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be on duty for less than 24 hours is working even though he is permitted to sleep or engage in other... specified hours is working even though she is permitted to sleep when not busy answering calls. It makes...

  9. 24-hour central blood pressure and intermediate cardiovascular phenotypes in untreated subjects

    PubMed Central

    Bednarek, Agnieszka; Jankowski, Piotr; Olszanecka, Agnieszka; Windak, Adam; Kawecka-Jaszcz, Kalina; Czarnecka, Danuta

    2014-01-01

    Background: Recently, 24-hour monitoring of central systolic blood pressure (SBP) has become available. However, the relation between end-organ damage and the 24-hour central SBP profile and variability has not so far been analyzed. Therefore, the aim of this cross-sectional study was to evaluate the relation between 24-hour central SBP, 24-hour central SBP profile as well as central SBP short-term variability and parameters of cardiac and vascular intermediate phenotypes. Methods: The study group consisted of 50 patients with newly diagnosed, untreated hypertension (age 40.4 ± 11.5 years, 35 men) and 50 normotensive subjects (age 38.3 ± 12.0 years, 35 men). Applanation tonometry of the radial artery and the “n-point forward moving average” method were used to determine 24-hour central SBP. Each study participant underwent echocardiography and carotid ultrasonography. Results: 24-hour, daytime, and nighttime central SBP was related to left ventricle end-diastole diameter (p < 0.05), left ventricular mass index (p < 0.001), relative wall thickness (p < 0.05), E/E’ ratio (p < 0.01), and left atrium volume (p < 0.01). The nocturnal central SBP fall was not related to any of the mentioned parameters, whereas parameters of short-term variability were related to IMT in hypertensives only (p < 0.05). Conclusions: The present study showed that 24-hour central SBP is related to intermediate cardiac phenotypes as assessed by echocardiography whereas short-term central SBP variability is mainly related to vascular phenotype as determined by IMT. PMID:25628959

  10. Managing sleep and wakefulness in a 24-hour world

    PubMed Central

    Coveney, Catherine M

    2014-01-01

    This article contributes to literature on the sociology of sleep by exploring the sleeping practices and subjective sleep experiences of two social groups: shift workers and students. It draws on data, collected in the UK from 25 semi-structured interviews, to discuss the complex ways in which working patterns and social activities impact upon experiences and expectations of sleep in our wired awake world. The data show that, typically, sleep is valued and considered to be important for health, general wellbeing, appearance and physical and cognitive functioning. However, sleep time is often cut back on in favour of work demands and social activities. While shift workers described their efforts to fit in an adequate amount of sleep per 24-hour period, for students, the adoption of a flexible sleep routine was thought to be favourable for maintaining a work–social life balance. Collectively, respondents reported using a wide range of strategies, techniques, technologies and practices to encourage, overcome or delay sleep(iness) and boost, promote or enhance wakefulness/alertness at socially desirable times. The analysis demonstrates how social context impacts not only on how we come to think about sleep and understand it, but also how we manage or self-regulate our sleeping patterns. PMID:23957268

  11. [Necessity of a 24-hour system of blood transfusion testing].

    PubMed

    Kishimoto, Yuji

    2003-01-01

    The preventive effects of a 24-hour system of blood transfusion testing on mistyping of transfused blood was examined. Blood transfusion tests have been performed by blood transfusion technologists during working hours and by physicians at other times. In March 2000, we introduced a system in which technologists perform blood transfusion tests after working hours. Technologists of the Blood Transfusion Unit and Central Clinical Laboratory perform the test jointly, and column agglutination technology was introduced as the test method. A computer system setup exclusively for the testing was also introduced to perform computer cross-matching. Since transfusion error is likely to occur during emergency blood transfusion, a manual was established to prioritize safety. After introduction of the system, mistyping that may have been caused by inaccurate blood test results markedly decreased, confirming the usefulness of this system for prevention of mistyping. In addition, transfusion errors also decreased in wards and the improved system increased the safety of the entire medical care system. The frequency of mistyping was about 1% when physicians performed blood typing, showing the importance of clinical technologists for blood transfusion tests. PMID:12652691

  12. Cognitive Performance during a 24-Hour Cold Exposure Survival Simulation

    PubMed Central

    Hartley, Geoffrey L.; Zaharieva, Dessi; Basset, Fabien A.; Hynes, Zach

    2016-01-01

    Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (Tc) and cognitive test battery (CTB) performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature). Participants (recruited from those who have regular occupational exposure to cold) were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease Tc after exposure and to eliminate the typical 0.5–1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance. PMID:27478839

  13. Cognitive Performance during a 24-Hour Cold Exposure Survival Simulation.

    PubMed

    Taber, Michael J; Hartley, Geoffrey L; McGarr, Gregory W; Zaharieva, Dessi; Basset, Fabien A; Hynes, Zach; Haman, Francois; Pinet, Bernard M; DuCharme, Michel B; Cheung, Stephen S

    2016-01-01

    Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (T c) and cognitive test battery (CTB) performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature). Participants (recruited from those who have regular occupational exposure to cold) were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease T c after exposure and to eliminate the typical 0.5-1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance. PMID:27478839

  14. Effect of overtime work on 24-hour ambulatory blood pressure.

    PubMed

    Hayashi, T; Kobayashi, Y; Yamaoka, K; Yano, E

    1996-10-01

    Recently, the adverse effects of long working hours on the cardiovascular systems of workers in Japan, including "Karoshi" (death from overwork), have been the focus of social concern. However, conventional methods of health checkups are often unable to detect the early signs of such adverse effects. To evaluate the influence of overtime work on the cardiovascular system, we compared 24-hour blood pressure measurements among several groups of male white-collar workers. As a result, for those with normal blood pressure and those with mild hypertension, the 24-hour average blood pressure of the overtime groups was higher than that of the control groups; for those who periodically did overtime work, the 24-hour average blood pressure and heart rate during the busy period increased. These results indicate that the burden on the cardiovascular system of white-collar workers increases with overtime work. PMID:8899576

  15. Insights about serum sodium behavior after 24 hours of continuous renal replacement therapy

    PubMed Central

    Romano, Thiago Gomes; Martins, Cassia Pimenta Barufi; Mendes, Pedro Vitale; Besen, Bruno Adler Maccagnan Pinheiro; Zampieri, Fernando Godinho; Park, Marcelo

    2016-01-01

    Objective The aim of this study was to investigate the clinical and laboratorial factors associated with serum sodium variation during continuous renal replacement therapy and to assess whether the perfect admixture formula could predict 24-hour sodium variation. Methods Thirty-six continuous renal replacement therapy sessions of 33 patients, in which the affluent prescription was unchanged during the first 24 hours, were retrieved from a prospective collected database and then analyzed. A mixed linear model was performed to investigate the factors associated with large serum sodium variations (≥ 8mEq/L), and a Bland-Altman plot was generated to assess the agreement between the predicted and observed variations. Results In continuous renal replacement therapy 24-hour sessions, SAPS 3 (p = 0.022) and baseline hypernatremia (p = 0.023) were statistically significant predictors of serum sodium variations ≥ 8mEq/L in univariate analysis, but only hypernatremia demonstrated an independent association (β = 0.429, p < 0.001). The perfect admixture formula for sodium prediction at 24 hours demonstrated poor agreement with the observed values. Conclusions Hypernatremia at the time of continuous renal replacement therapy initiation is an important factor associated with clinically significant serum sodium variation. The use of 4% citrate or acid citrate dextrose - formula A 2.2% as anticoagulants was not associated with higher serum sodium variations. A mathematical prediction for the serum sodium concentration after 24 hours was not feasible. PMID:27410407

  16. Chapter 4: 24-hour recall and diet record methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The two methods described in this chapter, the 24-hour dietary recall (24hdr) and the food record (FR) method, are the currently preferred methods of dietary intake assessment, and are based on foods and amounts actually consumed by an individual on one or more specific days. This minimizes some sou...

  17. The 24 Hours before Hospitalization: Factors Related to Suicide Attempting.

    ERIC Educational Resources Information Center

    Chiles, John A.; And Others

    1986-01-01

    Psychiatric inpatients (N=59) were interviewd concerning psychological and environmental events that occurred in the 24 hours prior to their hospitalization. Suicide attempters were more likely to have used alcohol or marijuana and less likely to have contacted a health care professional than suicide ideators, even when past history of suicide…

  18. The effect of Operation 24 Hours on reducing collision in the City of Edmonton.

    PubMed

    Halim, Siana; Jiang, Heming

    2013-09-01

    In the City of Edmonton, in order to reduce the prevalence of collisions, the Operation 24 Hours program (OPS24) was developed by using existing police and transportation services resources. The program uses traditional manned police speed enforcement method, which are supplemented by traffic safety messages displayed on permanent and mobile dynamic messaging signs (DMS). In this paper, collision data analysis was performed by looking at the daily number of collisions from 2008 to 2011 that covers 28 Operation 24 Hours (OPS24) events. The objective of the collision data analysis is to analyze if there is a reduction in collision frequencies after OPS24 was held and examined how long the collision reduction effect last. Weather factors such as temperature, thickness of snow, and wind gust have been considered by many as a great influence on collision occurrences, especially in a city with long and cold winter such as Edmonton. Therefore, collision modeling was performed by considering these external weather factors. To analyze the linear and periodic trend of different collision types (injury, fatal, and property damage only (PDO)) and examine the influence of weather factors on collisions, negative binomial time series model that accounts for seasonality and weather factors was used to model daily collision data. The modeling also considered collision proportion to account for missing traffic volume data; the Gaussian time series model that accounts for seasonality and weather factors was used to model collision proportion. To estimate the collision trend and test for changes in collision levels before/after OPS24, interrupted time series model with segmented regression was used. While for estimating how long the effect of the OPS24 last, change point method was applied. PMID:23727551

  19. Characterization of pulmonary protein profiles in response to zinc oxide nanoparticles in mice: a 24-hour and 28-day follow-up study

    PubMed Central

    Pan, Chih-Hong; Chuang, Kai-Jen; Chen, Jen-Kun; Hsiao, Ta-Chih; Lai, Ching-Huang; Jones, Tim P; BéruBé, Kelly A; Hong, Gui-Bing; Ho, Kin-Fai; Chuang, Hsiao-Chi

    2015-01-01

    Although zinc oxide nanoparticles (ZnONPs) are recognized to cause systemic disorders, little is known about the mechanisms that underlie the time-dependent differences that occur after exposure. The objective of this study was to investigate the mechanistic differences at 24 hours and 28 days after the exposure of BALB/c mice to ZnONPs via intratracheal instillation. An isobaric tag for the relative and absolute quantitation coupled with liquid chromatography/tandem mass spectrometry was used to identify the differential protein expression, biological processes, molecular functions, and pathways. A total of 18 and 14 proteins displayed significant changes in the lung tissues at 24 hours and 28 days after exposure, respectively, with the most striking changes being observed for S100-A9 protein. Metabolic processes and catalytic activity were the main biological processes and molecular functions, respectively, in the responses at the 24-hour and 28-day follow-up times. The glycolysis/gluconeogenesis pathway was continuously downregulated from 24 hours to 28 days, whereas detoxification pathways were activated at the 28-day time-point after exposure. A comprehensive understanding of the potential time-dependent effects of exposure to ZnONPs was provided, which highlights the metabolic mechanisms that may be important in the responses to ZnONP. PMID:26251593

  20. Characterization of pulmonary protein profiles in response to zinc oxide nanoparticles in mice: a 24-hour and 28-day follow-up study.

    PubMed

    Pan, Chih-Hong; Chuang, Kai-Jen; Chen, Jen-Kun; Hsiao, Ta-Chih; Lai, Ching-Huang; Jones, Tim P; BéruBé, Kelly A; Hong, Gui-Bing; Ho, Kin-Fai; Chuang, Hsiao-Chi

    2015-01-01

    Although zinc oxide nanoparticles (ZnONPs) are recognized to cause systemic disorders, little is known about the mechanisms that underlie the time-dependent differences that occur after exposure. The objective of this study was to investigate the mechanistic differences at 24 hours and 28 days after the exposure of BALB/c mice to ZnONPs via intratracheal instillation. An isobaric tag for the relative and absolute quantitation coupled with liquid chromatography/tandem mass spectrometry was used to identify the differential protein expression, biological processes, molecular functions, and pathways. A total of 18 and 14 proteins displayed significant changes in the lung tissues at 24 hours and 28 days after exposure, respectively, with the most striking changes being observed for S100-A9 protein. Metabolic processes and catalytic activity were the main biological processes and molecular functions, respectively, in the responses at the 24-hour and 28-day follow-up times. The glycolysis/gluconeogenesis pathway was continuously downregulated from 24 hours to 28 days, whereas detoxification pathways were activated at the 28-day time-point after exposure. A comprehensive understanding of the potential time-dependent effects of exposure to ZnONPs was provided, which highlights the metabolic mechanisms that may be important in the responses to ZnONP. PMID:26251593

  1. The Three-Continent, 24-Hour Help Desk: An Academic First?

    ERIC Educational Resources Information Center

    Sykes, Jean

    2002-01-01

    Describes Follow the Sun, a computer help-desk service that takes advantage of time differences around the world to permit four universities (University of Colorado Boulder, Australia's Macquarie and Newcastle universities, and the London School of Economics) to share services and provide 24-hour support to users. (EV)

  2. Axial Diffusivity of the Corona Radiata at 24 Hours Post-Stroke: A New Biomarker for Motor and Global Outcome.

    PubMed

    Moulton, Eric; Amor-Sahli, Mélika; Perlbarg, Vincent; Pires, Christine; Crozier, Sophie; Galanaud, Damien; Valabregue, Romain; Yger, Marion; Baronnet-Chauvet, Flore; Samson, Yves; Dormont, Didier; Rosso, Charlotte

    2015-01-01

    Fractional anisotropy (FA) is an effective marker of motor outcome at the chronic stage of stroke yet proves to be less efficient at early time points. This study aims to determine which diffusion metric in which location is the best marker of long-term stroke outcome after thrombolysis with diffusion tensor imaging (DTI) at 24 hours post-stroke. Twenty-eight thrombolyzed patients underwent DTI at 24 hours post-stroke onset. Ipsilesional and contralesional FA, mean (MD), axial (AD), and radial (RD) diffusivities values were calculated in different Regions-of-Interest (ROIs): (1) the white matter underlying the precentral gyrus (M1), (2) the corona radiata (CoRad), (3) the posterior limb of the internal capsule (PLIC) and (4) the cerebral peduncles (CP). NIHSS scores were acquired at admission, day 1, and day 7; modified Rankin Scores (mRS) at 3 months. Significant decreases were found in FA, MD, and AD of the ipsilesional CoRad and M1. MD and AD were also significantly lower in the PLIC. The ratio of ipsi and contralesional AD of the CoRad (CoRad-rAD) was the strongest diffusion parameter correlated with motor NIHSS scores on day 7 and with the mRS at 3 months. A Receiver-Operator Curve analysis yielded a model for the CoRad-rAD to predict good outcome based on upper limb NIHSS motor scores and mRS with high specificity and sensitivity. FA values were not correlated with clinical outcome. In conclusion, axial diffusivity of the CoRad from clinical DTI at 24 hours post-stroke is the most appropriate diffusion metric for quantifying stroke damage to predict outcome, suggesting the importance of early axonal damage. PMID:26562509

  3. Axial Diffusivity of the Corona Radiata at 24 Hours Post-Stroke: A New Biomarker for Motor and Global Outcome

    PubMed Central

    Moulton, Eric; Amor-Sahli, Mélika; Perlbarg, Vincent; Pires, Christine; Crozier, Sophie; Galanaud, Damien; Valabregue, Romain; Yger, Marion; Baronnet-Chauvet, Flore; Samson, Yves; Dormont, Didier; Rosso, Charlotte

    2015-01-01

    Fractional anisotropy (FA) is an effective marker of motor outcome at the chronic stage of stroke yet proves to be less efficient at early time points. This study aims to determine which diffusion metric in which location is the best marker of long-term stroke outcome after thrombolysis with diffusion tensor imaging (DTI) at 24 hours post-stroke. Twenty-eight thrombolyzed patients underwent DTI at 24 hours post-stroke onset. Ipsilesional and contralesional FA, mean (MD), axial (AD), and radial (RD) diffusivities values were calculated in different Regions-of-Interest (ROIs): (1) the white matter underlying the precentral gyrus (M1), (2) the corona radiata (CoRad), (3) the posterior limb of the internal capsule (PLIC) and (4) the cerebral peduncles (CP). NIHSS scores were acquired at admission, day 1, and day 7; modified Rankin Scores (mRS) at 3 months. Significant decreases were found in FA, MD, and AD of the ipsilesional CoRad and M1. MD and AD were also significantly lower in the PLIC. The ratio of ipsi and contralesional AD of the CoRad (CoRad-rAD) was the strongest diffusion parameter correlated with motor NIHSS scores on day 7 and with the mRS at 3 months. A Receiver-Operator Curve analysis yielded a model for the CoRad-rAD to predict good outcome based on upper limb NIHSS motor scores and mRS with high specificity and sensitivity. FA values were not correlated with clinical outcome. In conclusion, axial diffusivity of the CoRad from clinical DTI at 24 hours post-stroke is the most appropriate diffusion metric for quantifying stroke damage to predict outcome, suggesting the importance of early axonal damage. PMID:26562509

  4. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population

    PubMed Central

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-01-01

    Abstract The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China. This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated. A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19–61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 am in winter and at 2:00 am in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 pm to 8:00 am, except for 6:00 am, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05). The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  5. Seasonal changes of 24-hour intraocular pressure rhythm in healthy Shanghai population.

    PubMed

    Cheng, Jingyi; Xiao, Ming; Xu, Huan; Fang, Shaobin; Chen, Xu; Kong, Xiangmei; Sun, Xinghuai

    2016-08-01

    The aim of the present study was to investigate and compare the 24-hour intraocular pressure (IOP) rhythms in winter and summer in the healthy population of Shanghai, China.This is a cross-sectional study in which 24-hour IOP measurements were taken for all eligible healthy volunteers in winter and summer, respectively, and the temperature, hours of sunlight (sunlight time), and circulatory parameters, including heart rate, systolic blood pressure, and diastolic blood pressure, were also recorded. The 24-hour IOP curves and IOP parameters (mean, peak, trough, and fluctuation of IOP together with the diurnal-to-nocturnal IOP change) in winter and summer were obtained and compared. The magnitude of IOP changes from summer to winter was also calculated.A total of 29 participants (58 eyes), 14 (48.28%) male and 15 (51.72%) female, aged 43.66 ± 12.20 (19-61) years, were considered eligible for this study. Generally, IOP decreased progressively before noon, increased notably in the nocturnal period, and peaked at 12:00 AM in winter and at 2:00 AM in summer. The pattern of 24-hour IOP in winter and summer was significantly different (P = 0.002). The average IOPs from 4:00 PM to 8:00 AM, except for 6:00 AM, were significantly higher in winter (P < 0.05). However, no significant differences were shown after adjusting for temperature and/or sunlight time. From summer to winter, the extent of IOP increase was mostly around 0 to 3 mm Hg, and the IOPs increased more significantly in the nocturnal period than in the diurnal period (P = 0.05).The 24-hour IOP rhythms were different in winter and summer, with higher IOP level in winter. Temperature and sunlight time, which are independent of heart rate and blood pressure, affected the 24-hour IOP rhythms in healthy people in Shanghai, China. Further investigations are expected for the rhythm of some endogenous substance secretion and the inner mechanism of regulation of IOP. PMID:27495076

  6. [Identification of paroxysmal, transient arrhythmias: Intermittent registration more efficient than the 24-hour Holter monitoring].

    PubMed

    Hendrikx, Tijn; Rosenqvist, Mårten; Sandström, Herbert; Persson, Mats; Hörnsten, Rolf

    2015-01-01

    Many patients suffer from palpitations or dizziness/presyncope. These patients are often referred for Holter ECG (24 hour), although the sensitivity for detecting arrhythmias is low. A new method, short intermittent regular and symptomatic ECG registrations at home, might be a convenient and more sensitive alternative also suitable for primary health care. In this case report we present a patient who had contacted health care several times during a seven year period for paroxysmal palpitations. Routine examination with 24 hour Holter ECG and event recorder did not result in a diagnosis. Using intermittent handheld ECG registration at home, a paroxysmal supraventricular arrhythmia was diagnosed. Further investigation revealed that the patient had a concealed Wolff-Parkinson-White (WPW) syndrome. PMID:25584602

  7. A New Method to Make 24-Hour Urine Collection More Convenient: A Validity Study

    PubMed Central

    2014-01-01

    Background and Objectives. This study proposes a novel urine collection device that can divide each urine collection into 20 parts and store and cool just one part. The aim of the current study is to compare measured biomarkers from the proposed urine collection device to those of conventional 24-hour sampling method. We also hypothesized that the new method would significantly increase patients' adherence to the timed urine collection. Methods. Two 24-hour urine samples with the conventional method and with the new automated urine collection device that uses just one-twentieth of each void were obtained from 40 healthy volunteers. Urine parameters including volume, creatinine, and protein levels were compared between the two methods and the agreement of two measurements for each subject was reported through Bland-Altman plots. Results. Our results confirmed that for all three variables, there is a positive correlation (P < 0.001) between the two measurements and high degree of agreement could be seen in Bland-Altman plots. Moreover, more subjects reported the new method as “more convenient” for 24-hour urine collection. Conclusions. Our results clearly indicate that a fixed proportion of each void may significantly reduce the urine volume in timed collections and this, in turn, may increase subjects' adherence to this difficult sampling. PMID:24963405

  8. Phase II trial of cyclophosphamide, leucovorin, 5-fluorouracil 24-hour infusion and tamoxifen in pancreatic cancer.

    PubMed

    Eckel, F; Lersch, C; Lippl, F; Assmann, G; Schulte-Frohlinde, E

    2000-09-01

    Leucovorin modulates the cytotoxic effects of 5-fluorouracil (5-FU) in the treatment of cancer. 24-hour infusion of 5-FU has been shown to enhance antitumor activity in colorectal cancer compared to bolus infusion. According to experimental data cyclophosphamide and tamoxifen may enhance the effectiveness of leucovorin and 5-FU. A phase II trial was initiated to evaluate the effect of a combination of low-dose cyclophosphamide (C), leucovorin (L), 5-FU (F) and tamoxifen (T) (CLFT) in advanced pancreatic cancer. Fifty patients were treated monthly with 300 mg/m2 cyclophosphamide and weekly with 500 mg/m2 leucovorin followed by a 24-hour infusion of 2000 mg/m2 5-FU and tamoxifen 20 mg bid. Three patients had a partial response (6%), two a minor response (4%) and 32 (64%) no change of disease. The median survival time was 8.5 months for all patients, the median time to progression of disease was 4.6 months and the 1-year survival rate was 28%. CLFT was fairly well tolerated. These data suggest that biochemical modulation of 24-hour infusional 5-FU with leucovorin together with cyclophosphamide and tamoxifen has some positive effects in the treatment of pancreatic cancer. PMID:11144522

  9. Recovery of amplitude integrated electroencephalographic background patterns within 24 hours of perinatal asphyxia

    PubMed Central

    van Rooij, L G M; Toet, M; Osredkar, D; van Huffelen, A C; Groenendaal, F; de Vries, L S

    2005-01-01

    Objective: To assess the time course of recovery of severely abnormal initial amplitude integrated electroencephalographic (aEEG) patterns (flat trace (FT), continuous low voltage (CLV), or burst suppression (BS)) in full term asphyxiated neonates, in relation to other neurophysiological and neuroimaging findings and neurodevelopmental outcome. Methods: A total of 190 aEEGs of full term infants were reviewed. The neonates were admitted within 6 hours of birth to the neonatal intensive care unit because of perinatal asphyxia, and aEEG recording was started immediately. In all, 160 infants were included; 65 of these had an initial FT or CLV pattern and 25 an initial BS pattern. Neurodevelopmental outcome was assessed using a full neurological examination and the Griffiths' mental developmental scale. Results: In the FT/CLV group, the background pattern recovered to continuous normal voltage within 24 hours in six of the 65 infants (9%). All six infants survived the neonatal period; one had a severe disability, and five were normal at follow up. In the BS group, the background pattern improved to normal voltage in 12 of the 25 infants (48%) within 24 hours. Of these infants, one died, five survived with moderate to severe disability, two with mild disability, and four were normal. The patients who did not recover within 24 hours either died in the neonatal period or survived with a severe disability. Conclusion: In this study there was a small group of infants who presented with a severely abnormal aEEG background pattern within six hours of birth, but who achieved recovery to a continuous normal background pattern within the first 24 hours. Sixty one percent of these infants survived without, or with a mild, disability. PMID:15846017

  10. Mechanical properties of direct and indirect composites after storage for 24 hours and 10 months

    PubMed Central

    Alves, Paula Barbosa; Brandt, William Cunha; Neves, Ana Christina Claro; Cunha, Leonardo Gonçalves; Silva-Concilio, Lais Regiane

    2013-01-01

    Objective: The objective of this study was to evaluate the diametral tensile strength (DTS) and Knoop hardness (KH) of direct (Filtek Z350-3M/ESPE and Charisma-Heraeus Kulzer) and indirect composites (Sinfony-3M/ESPE and Signum-Heraeus Kulzer) kept in storage for two periods of time, 24 hours and 10 months, in distilled water. Methods: Twenty-five specimens of each material were prepared. DTS (n=10) was tested using a universal testing machine (Versat, model 2000) at a crosshead speed of 1.0 mm/min. KH (n=5) was measured using Knoop micro-hardness (HMV-2000; 50 gf for 15 s). All tests were performed 24 hours after polymerization and after 10 months of storage in distilled water at 37°C. The data were statistically analyzed using Kolmogorov-Smirnov, ANOVA and t-Student (P=.05). Results: Filtek Z350, Sinfony, and Signum showed higher DTS values than Charisma after 24 hours. After storage, Sinfony and Signum showed higher DTS values because the storage did not influence the DTS values of the indirect composites. Filtek Z350 showed higher KH values after 24 hours and after storage than other composites; the storage influenced the KH of all composites except Sinfony. Conclusion: Storage for 10 months did not influence the properties of the indirect composite Sinfony. In general, the indirect composites showed higher DTS values than direct composites, especially after 10 months storage. The direct composite Filtek Z350 obtained the highest KH values regardless of storage. PMID:23407869

  11. Preparation and results of a 24-hour orbital flight.

    PubMed

    Titov, G S

    1963-01-01

    The space age presents man with unprecedented opportunities for discovery and for cooperative endeavors to benefit all mankind. My flight of August 6-7, 1961 was conducted for the purpose of determining whether man can stay and work effectively and whether all systems of the spaceship can operate successfully during a period of 24 hours in space. The flight of Vostok II represents an experimental step in a logical sequence which included the first earth orbiting flight of USSR citizen Yuri A. Gagarin. Preparation for the flight included the study of theoretical and applied subjects, testing in various kinds of apparatus which provide acceleration, heat and isolation experience, brief airborne weightless flights and parachute landings, in addition to extensive training in a real spacecraft having simulators for normal and emergency contingencies of space flight. The actual flight was therefore carried out with a sense of confidence and familiarity and with continuous close radio contact with ground centers from whom my fellow cosmonauts served as spokesmen. Sequential boosters totaling 600 000 kg thrust placed the 4731 kg spaceship into a perfect orbit varying in altitude from 178-246 km in a plane 64 degrees 58' inclined to the equator. The spaceship made 17 orbits around the earth landing 25 hours, 18 minutes after take-off. The cabin had full atmospheric pressure and a comfortable habitability which could be extended for 10 days. I was able to maneuver the spaceship and perform many other control functions, make observations and take pictures of the earth and its cloud cover, eat meals and sleep all with good efficiency. I experienced mild symptoms suggestive of seasickness which were aggravated by head turning, ameliorated by sleep and entirely relieved by resumption of g-loading during descent. Altogether analyses of the physical and structural performance of the spaceship and the continuously monitored physiological responses of the pilot indicate that all

  12. 24-Hour Measurement of Gastric pH in Rural South Africa

    PubMed Central

    Sammon, Alastair M.; Ndebia, Eugene J.; Umapathy, Ekambaram; Iputo, Jehu E.

    2015-01-01

    Background. Previous studies have established norms of 24-hour gastric pH profiles for western countries. This study was designed to establish the pattern for a rural African population with a high incidence of oesophageal cancer. Methods. After lower oesophageal manometry a probe was placed 10 cm distal to the lower oesophageal sphincter. We carried out 24-hour ambulatory monitoring of gastric pH on 59 healthy subjects. This was satisfactorily completed on 26 female and 18 male (age 21–64, median 35) subjects in the Transkei region of South Africa. Results. The mean 24 hour gastric pH was 2.84 and the mean night-time pH was 3.7. 40 volunteers recorded a night-time pH reaching over 4. 33 volunteers recorded a night-time pH over 7. Night-time alkalinisation was present for 136.4 minutes (25th centile 22.8, 75th centile 208.1) at pH4 or over, and 79.3 (2.5, 122.7) minutes at pH7 or over. Episodes of rapid alkaline rise were 17 (10, 47). 21.1% of these occurred while supine. 35 of 36 tested subjects were positive for H. pylori IgG. Conclusion. Gastric alkalinisation is common in Transkei, at a higher pH than that reported in other studies, and is sustained longer. Nighttime alkalinisation is frequent. This suggests a high level of duodenogastric reflux. PMID:25861260

  13. [Program for early detection of illness level in foals during the first 24 hours of life].

    PubMed

    Bostedt, H; Hospes, R; Herfen, K

    1997-11-01

    Basing on exact investigations of normal behaviour and abnormalities in newborn and up to 24 hours old foals a program for evaluation, comprehending exogeniously judgable criteria, was developed. It aims at a quick recognition of aberrations in behaviour. The program includes a score, which allows early diagnosis of even subtile abnormalities. As a result, a veterinary surgeon should be consulted if the score exposes a critical situation, so that therapy can be started in time. Furthermore informations about investigations on blood-glucose- and immunoglobulin-G-concentration in relation to neonatal foal diseases are given. PMID:9451764

  14. Tasimelteon for the treatment of non-24-hour sleep-wake disorder.

    PubMed

    Neubauer, D N

    2015-01-01

    Tasimelteon (Hetlioz®), a melatonin receptor agonist, is the first, and, at the time of the publication, the only drug to be approved by the U.S. Food and Drug Administration (FDA) for the treatment of non-24-hour sleep-wake disorder (non-24). This circadian rhythm disorder occurs most commonly in blind individuals without light perception, and it results from their inability to entrain to the 24-hour photoperiod, although the indication does not specify a particular patient population. Non-24 is characterized by a persistent cycle of nighttime insomnia and daytime sleepiness, alternating with asymptomatic periods depending on an individual's degree of circadian rhythm synchronization with the photoperiod at any particular time. Phase II clinical trials in healthy individuals confirmed the circadian phase-shifting potential of tasimelteon. Phase III trials in totally blind subjects diagnosed with non-24 demonstrated the efficacy of tasimelteon in reducing both nighttime wakefulness and daytime napping. Physiologic monitoring revealed that tasimelteon resulted in a higher proportion of individuals becoming entrained to the 24-hour cycle compared with placebo. Safety assessments indicated that tasimelteon is well tolerated, with the most common adverse events being headache, alanine aminotransferase elevation, nightmares or unusual dreams, and upper respiratory or urinary tract infections. Tasimelteon is available as a capsule in a single 20-mg dose and it must be obtained through Vanda Pharmaceutical's HetliozSolutions program with dispensing through a specialty pharmacy. Safety studies in blind individuals diagnosed with non-24 are ongoing and a future clinical trial with Smith-Magenis syndrome patients is planned. PMID:25685859

  15. Executive Functions are not Affected by 24 Hours of Sleep Deprivation: A Color-Word Stroop Task Study

    PubMed Central

    Dixit, Abhinav; Mittal, Tushar

    2015-01-01

    Background: Sleep is an important factor affecting cognitive performance. Sleep deprivation results in fatigue, lack of concentration, confusion and sleepiness along with anxiety, depression and irritability. Sleep deprivation can have serious consequences in professions like armed forces and medicine where quick decisions and actions need to be taken. Color-Word Stroop task is one of the reliable tests to assess attention and it analyzes the processing of information in two dimensions i.e., reading of words and naming of colour. The evidence regarding the effect of sleep deprivation on Stroop interference is conflicting. The present study evaluated the effect of 24 hours of sleep deprivation on reaction time and interference in Stroop task. Materials and Methods: The present study was done on 30 healthy male medical student volunteers in the age group of 18-25 years after taking their consent and clearance from Institute Ethics Committee. Recordings of Stroop task were at three times: baseline (between 7-9 am), after 12 hours (7-9 pm) and after 24 hours (7-9 am, next day). The subjects were allowed to perform normal daily activities. Results: The study revealed a significant increase in reaction time after 24 hours of sleep deprivation in comparison to baseline and after 12 hours of sleep deprivation. There was no significant change in interference and facilitation after sleep deprivation in comparison to baseline. The number of errors also did not show any significant change after sleep deprivation. Conclusion: The study indicated that there was slowing of responses without change in executive functions after 24 hours of sleep deprivation. It is probable that 24 hours of sleep deprivation does not bring about change in areas of brain affecting executive functions in healthy individuals who have normal sleep cycle. The present study indicated that in professions like armed forces and medicine working 24 hours at a stretch can lead to decrease in motor responses

  16. Bioenergetical and Cardiac Adaptations of Pilots to a 24-Hour Team Kart Race.

    PubMed

    Durand, Sylvain; Ripamonti, Michael; Rahmani, Abderrahmane; Beaune, Bruno

    2015-11-01

    This study aimed to evaluate energy expenditure (EE) and heart rate (HR) response in kart pilots to successive driving bouts during a 24-hour team race. Eight adult male pilots (22.8 ± 4.1 years) participated to a team 24-hour speedway kart race in Le Mans (France). They alternatively piloted a 390 cm kart. Each relay was 45 minutes long and each pilot performed 4 relays. For each pilot, mean speeds were calculated from lap-to-lap duration recordings using a telemetric infrared timing device. Heart rate values were recorded continuously on 5-second intervals using a portable cardiometric device. Total energy expenditure (EET) and physical activity ratio (PAR) were determined by accelerometry. To pilot a kart during 45 minutes at a mean speed around 62 km·h induces a 300-kcal EET, corresponding to a 5.6-Mets PAR. This effort is responsive for a 73 b·min increase in HR, from 84.1 ± 7.6 to 157.4 ± 11.0 b·min (82% maximal heart rate intensity). However, during this relay period, HR values seemed independent to mean speed performance and bioenergetical values. Thus, in the context of the 24-hour team race, the variability in effort made during each relay and relay succession did not alter bioenergetical adaptation of pilots to kart driving. The high EE and HR values would be better explained by both emotional stress and environmental constraints such as speedway configuration and vibrations. The way how these factors specifically influence bioenergetical demand, and their relative importance, has to be specified to optimize training procedure and recommendations. PMID:25029011

  17. Comparison of observation level versus 24-hour average atmospheric loading corrections in VLBI analysis

    NASA Astrophysics Data System (ADS)

    MacMillan, D. S.; van Dam, T. M.

    2009-04-01

    Variations in the horizontal distribution of atmospheric mass induce displacements of the Earth's surface. Theoretical estimates of the amplitude of the surface displacement indicate that the predicted surface displacement is often large enough to be detected by current geodetic techniques. In fact, the effects of atmospheric pressure loading have been detected in Global Positioning System (GPS) coordinate time series [van Dam et al., 1994; Dong et al., 2002; Scherneck et al., 2003; Zerbini et al., 2004] and very long baseline interferometery (VLBI) coordinates [Rabble and Schuh, 1986; Manabe et al., 1991; van Dam and Herring, 1994; Schuh et al., 2003; MacMillan and Gipson, 1994; and Petrov and Boy, 2004]. Some of these studies applied the atmospheric displacement at the observation level and in other studies, the predicted atmospheric and observed geodetic surface displacements have been averaged over 24 hours. A direct comparison of observation level and 24 hour corrections has not been carried out for VLBI to determine if one or the other approach is superior. In this presentation, we address the following questions: 1) Is it better to correct geodetic data at the observation level rather than applying corrections averaged over 24 hours to estimated geodetic coordinates a posteriori? 2) At the sub-daily periods, the atmospheric mass signal is composed of two components: a tidal component and a non-tidal component. If observation level corrections reduce the scatter of VLBI data more than a posteriori correction, is it sufficient to only model the atmospheric tides or must the entire atmospheric load signal be incorporated into the corrections? 3) When solutions from different geodetic techniques (or analysis centers within a technique) are combined (e.g., for ITRF2008), not all solutions may have applied atmospheric loading corrections. Are any systematic effects on the estimated TRF introduced when atmospheric loading is applied?

  18. Intermittent short ECG recording is more effective than 24-hour Holter ECG in detection of arrhythmias

    PubMed Central

    2014-01-01

    Background Many patients report symptoms of palpitations or dizziness/presyncope. These patients are often referred for 24-hour Holter ECG, although the sensitivity for detecting relevant arrhythmias is comparatively low. Intermittent short ECG recording over a longer time period might be a convenient and more sensitive alternative. The objective of this study is to compare the efficacy of 24-hour Holter ECG with intermittent short ECG recording over four weeks to detect relevant arrhythmias in patients with palpitations or dizziness/presyncope. Methods Design: prospective, observational, cross-sectional study. Setting: Clinical Physiology, University Hospital. Patients: 108 consecutive patients referred for ambiguous palpitations or dizziness/presyncope. Interventions: All individuals underwent a 24-hour Holter ECG and additionally registered 30-second handheld ECG (Zenicor EKG® thumb) recordings at home, twice daily and when having cardiac symptoms, during 28 days. Main outcome measures: Significant arrhythmias: atrial fibrillation (AF), paroxysmal supraventricular tachycardia (PSVT), atrioventricular (AV) block II–III, sinus arrest (SA), wide complex tachycardia (WCT). Results 95 patients, 42 men and 53 women with a mean age of 54.1 years, completed registrations. Analysis of Holter registrations showed atrial fibrillation (AF) in two patients and atrioventricular (AV) block II in one patient (= 3.2% relevant arrhythmias [95% CI 1.1–8.9]). Intermittent handheld ECG detected nine patients with AF, three with paroxysmal supraventricular tachycardia (PSVT) and one with AV-block-II (= 13.7% relevant arrhythmias [95% CI 8.2–22.0]). There was a significant difference between the two methods in favour of intermittent ECG with regard to the ability to detect relevant arrhythmias (P = 0.0094). With Holter ECG, no symptoms were registered during any of the detected arrhythmias. With intermittent ECG, symptoms were registered during half of the arrhythmia

  19. To Compare the Microleakage Among Experimental Adhesives Containing Nanoclay Fillers after the Storages of 24 Hours and 6 Months

    PubMed Central

    Mousavinasab, Seyed Mostafa; Atai, Mohammad; Alavi, Bagher

    2011-01-01

    Objectives: To compare the microleakage among experimental adhesives containing nanoclay fillers after the storages of 24 hours and 6 months. Materials and Methods: Class V cavities were prepared on extracted human molars with the occlusal margins located in enamel and the cervical margins in cementum. Phosphoric acid was applied to the enamel and dentin margins.Subsequently, the cavities were treated using four groups of experimental adhesive systems and restored with a resin composite. Adper Single Bond® was used as control group. After 24- hour and 6- month storages, the samples were subjected to thermocycling shocks and then immersed in silver nitrate as well as developer solution and finally evaluated for leakage. The data were analyzed using SPSS software. Results: Based on Kruskal –Wallis test, significant differences were found between groups regarding microleakage. The Mann- Whitney test showed that Leakage was significantly lower in Adper Single Bond® compared to the other groups in dentinal margins after 24 hours and 6 months and in enamel margins after 6 months. The Wilcoxon Signed Ranks test showed that the enamel leakage in experimental adhesives was significantly lower than dentinal leakage after 24 hours as well as enamel leakage in Adper Single Bond and adhesive with 0.5% PMAA-g-nanoclay was significantly lower than dentinal margins after storage period of 6 months. Conclusion: All the experimental adhesives were effective in reducing enamel leakage after 24 hours, but were not effective in reducing dentinal leakage after 24 hours as well as in enamel and dentinal leakage after a 6-month storage. No improvement was observed in the microleakage in dentin in both short (24 hrs) and long times (6 months). The high microleakage in the adhesives is probably attributed to the high concentration of HEMA in the recipe of the bonding agent. PMID:21566692

  20. Comparison of 3 different anesthetic techniques on 24-hour recovery after otologic surgical procedures.

    PubMed

    Jellish, W S; Leonetti, J P; Fahey, K; Fury, P

    1999-03-01

    Intravenous propofol anesthesia is better than inhalational anesthesia for otologic surgery, but cost and intraoperative movement make this technique prohibitive. This study compares a propofol sandwich anesthetic with a total propofol or inhalational anesthetic for otologic surgery to determine which produces the best perioperative conditions and least expense. One hundred twenty patients undergoing ear surgery were randomly chosen to receive an anesthetic with either isoflurane (INHAL), total propofol (TPROP), or propofol used in conjunction with isoflurane (PSAND). Postoperative wakeup and the incidence and severity of nausea, vomiting, and pain were compared among groups. Antiemetic administration and discharge times from recovery and the hospital were also compared. The groups were similar, but anesthesia times were longer in the INHAL group. Emergence from anesthesia after PSAND or TPROP was more rapid than after INHAL. Recovery during the next 24 hours was associated with less nausea and vomiting with PSAND than with INHAL. The cost of the PSAND anesthetic was similar to that of INHAL, and both were less than TPROP. PSAND anesthesia may be similar to TPROP and better than INHAL for otologic procedures. PSAND was less expensive than TPROP and produced a similar recovery profile and antiemetic effect in the 24-hour period after surgery. PMID:10064647

  1. Sleep in healthy elderly subjects: a 24-hour ambulatory polysomnographic study.

    PubMed

    Gigli, G L; Placidi, F; Diomedi, M; Maschio, M; Silvestri, G; Scalise, A; Marciani, M G

    1996-04-01

    It is still debated whether the deterioration of the sleep pattern, frequently reported by elderly subjects, is due only to aging per se. Other factors associated with aging or modifications of biological rhythms could also be involved. Elderly subjects frequently complain of daytime sleepiness, but it is not clear whether this actually represents a return to a polyphasic structure of sleep, or only a consequence of a disturbed night sleep. Ten healthy, independent and active elderly subjects (age > 72 years) were elevated by means of 24-hour ambulatory polysomnography. Findings of nocturnal sleep were compared with sleep of the same group in the 24-hour period and with sleep of young healthy controls. We observed a fragmentation of nocturnal sleep, but a fairly good representation of stages and a preservation of cyclicity. Except for three cases, with early or late times of sleep onset and wake-up, sleep disruption did not seem to be related to modification of circadian rhythms. Only three subjects presented undesired daytime naps, whereas the others either did not show daytime sleep at all, or were used to having their siesta after lunch since their young adulthood. In normal aging, daytime sleep does not constitute a social problem. Ambulatory polysomnography is a valid alternative to laboratory recordings in the identification of daytime sleep. PMID:8734563

  2. A Compute Perspective: Delivering Decision Support Products in 24 Hours from the Airborne Snow Observatory

    NASA Astrophysics Data System (ADS)

    Ramirez, P.; Mattmann, C. A.; Painter, T. H.; Seidel, F. C.; Trangsrud, A.; Hart, A. F.; Goodale, C. E.; Boardman, J. W.; Heneghan, C.; Verma, R.; Khudikyan, S.; Boustani, M.; Zimdars, P. A.; Horn, J.; Neely, S.

    2013-12-01

    The JPL Airborne Snow Observatory (ASO) must process 100s of GB of raw data to 100s of Terabytes of derived data in 24 hour Near Real Time (NRT) latency in a geographically distributed mobile compute and data-intensive processing setting. ASO provides meaningful information to water resource managers in the Western US letting them know how much water to maintain; or release, and what the prospectus of the current snow season is in the Sierra Nevadas. Providing decision support products processed from airborne data in a 24 hour timeframe is an emergent field and required the team to develop a novel solution as this process is typically done over months. We've constructed a system that combines Apache OODT; with Apache Tika; with the Interactive Data Analysis (IDL)/ENVI programming environment to rapidly and unobtrusively generate, distribute and archive ASO data as soon as the plane lands near Mammoth Lakes, CA. Our system is flexible, underwent several redeployments and reconfigurations, and delivered this critical information to stakeholders during the recent "Snow On" campaign March 2013 - June 2013. This talk will take you through a day in the life of the compute team from data acquisition, delivery, processing, and dissemination. Within this context, we will discuss the architecture of ASO; the open source software we used; the data we stored; and how it was delivered to its users. Moreover we will discuss the logistics, system engineering, and staffing that went into the developing, deployment, and operation of the mobile compute system.

  3. Population Pharmacokinetic Model Characterizing 24-Hour Variation in the Pharmacokinetics of Oral and Intravenous Midazolam in Healthy Volunteers

    PubMed Central

    van Rongen, A; Kervezee, L; Brill, MJE; van Meir, H; den Hartigh, J; Guchelaar, H-J; Meijer, JH; Burggraaf, J; van Oosterhout, F

    2015-01-01

    Daily rhythms in physiology may affect the pharmacokinetics of a drug. The aim of this study was to evaluate 24-hour variation in the pharmacokinetics of the CYP3A substrate midazolam. Oral (2 mg) and intravenous (1 mg) midazolam was administered at six timepoints throughout the 24-hour period in 12 healthy volunteers. Oral bioavailability (population mean value [RSE%] of 0.28 (7.1%)) showed 24-hour variation that was best parameterized as a cosine function with an amplitude of 0.04 (17.3%) and a peak at 12:14 in the afternoon. The absorption rate constant was 1.41 (4.7%) times increased after drug administration at 14:00. Clearance (0.38 L/min (4.8%)) showed a minor 24-hour variation with an amplitude of 0.03 (14.8%) L/min and a peak at 18:50. Simulations show that dosing time minimally affects the concentration time profiles after intravenous administration, while concentrations are higher during the day compared to the night after oral dosing, reflecting considerable variation in intestinal processes. PMID:26380154

  4. Population Pharmacokinetic Model Characterizing 24-Hour Variation in the Pharmacokinetics of Oral and Intravenous Midazolam in Healthy Volunteers.

    PubMed

    van Rongen, A; Kervezee, L; Brill, Mje; van Meir, H; den Hartigh, J; Guchelaar, H-J; Meijer, J H; Burggraaf, J; van Oosterhout, F

    2015-08-01

    Daily rhythms in physiology may affect the pharmacokinetics of a drug. The aim of this study was to evaluate 24-hour variation in the pharmacokinetics of the CYP3A substrate midazolam. Oral (2 mg) and intravenous (1 mg) midazolam was administered at six timepoints throughout the 24-hour period in 12 healthy volunteers. Oral bioavailability (population mean value [RSE%] of 0.28 (7.1%)) showed 24-hour variation that was best parameterized as a cosine function with an amplitude of 0.04 (17.3%) and a peak at 12:14 in the afternoon. The absorption rate constant was 1.41 (4.7%) times increased after drug administration at 14:00. Clearance (0.38 L/min (4.8%)) showed a minor 24-hour variation with an amplitude of 0.03 (14.8%) L/min and a peak at 18:50. Simulations show that dosing time minimally affects the concentration time profiles after intravenous administration, while concentrations are higher during the day compared to the night after oral dosing, reflecting considerable variation in intestinal processes. PMID:26380154

  5. Changes in platelet morphology and function during 24 hours of storage.

    PubMed

    Braune, S; Walter, M; Schulze, F; Lendlein, A; Jung, F

    2014-01-01

    aggregates could be visualized microscopically. After four hours, first debris and very small aggregates occurred. After 24 hours, platelet aggregates and also debris progressively increased. In accordance to this, the CASY system revealed an increase of platelet aggregates (up to 90 μm diameter) with increasing storage time. The percentage of CD62P positive platelets and PF4 increased significantly with storage time in resting PRP. When soluble ADP was added to stored PRP samples, the number of activatable platelets decreased significantly over storage time. The present study reveals the importance of a consequent standardization in the preparation of WB and PRP. Platelet morphology and function, particularly platelet reactivity to adherent or soluble agonists in their surrounding milieu, changed rapidly outside the vascular system. This knowledge is of crucial interest, particularly in the field of biomaterial development for cardiovascular applications, and may help to define common standards in the in vitro hemocompatibility testing of biomaterials. PMID:25227196

  6. Accuracy and Usefulness of Select Methods for Assessing Complete Collection of 24-Hour Urine: A Systematic Review.

    PubMed

    John, Katherine A; Cogswell, Mary E; Campbell, Norm R; Nowson, Caryl A; Legetic, Branka; Hennis, Anselm J M; Patel, Sheena M

    2016-05-01

    Twenty-four-hour urine collection is the recommended method for estimating sodium intake. To investigate the strengths and limitations of methods used to assess completion of 24-hour urine collection, the authors systematically reviewed the literature on the accuracy and usefulness of methods vs para-aminobenzoic acid (PABA) recovery (referent). The percentage of incomplete collections, based on PABA, was 6% to 47% (n=8 studies). The sensitivity and specificity for identifying incomplete collection using creatinine criteria (n=4 studies) was 6% to 63% and 57% to 99.7%, respectively. The most sensitive method for removing incomplete collections was a creatinine index <0.7. In pooled analysis (≥2 studies), mean urine creatinine excretion and volume were higher among participants with complete collection (P<.05); whereas, self-reported collection time did not differ by completion status. Compared with participants with incomplete collection, mean 24-hour sodium excretion was 19.6 mmol higher (n=1781 specimens, 5 studies) in patients with complete collection. Sodium excretion may be underestimated by inclusion of incomplete 24-hour urine collections. None of the current approaches reliably assess completion of 24-hour urine collection. PMID:26726000

  7. Value of 24-hour Delayed Film of Barium Enema for Evaluation of Colon Transit Function in Young Children with Constipation

    PubMed Central

    Yoo, Ha Yeong; Son, Jae Sung; Park, Hye Won; Kwak, Byung Ok; Kim, Hyeong Su; Bae, Sun Hwan

    2016-01-01

    Background/Aims A colon transit time test using radio-opaque markers (CTTRM) is considered the gold standard for evaluating colon transit function. A 24-hour delayed film of barium enema (BE) has been used as a supplementary method in structural evaluations. The aim of this study was to evaluate the utility of a 24-hour delayed BE film for assessing colon transit function in young children with constipation. Methods In total, 93 children with constipation who performed both single-contrast BE and CTTRM were enrolled in this study. Of these, the data from 70 children were analyzed (males 33, females 37; mean age [range], 5.63 ± 2.94 [2–14] years). The basic principle of the study is “velocity = distance/time”. Time values were identified in both studies, and the colon length and distance of barium movement were measured on the 24-hour delayed BE film. Thus, colon transit velocity values could be calculated using both methods. The correlation between colon transit velocity using a 24-hour delayed BE film versus CTTRM was analyzed statistically. Results Median value (interquartile range) of colon transit velocity using CTTRM was 1.57 (1.07–2.89) cm/hr, and that using BE of that was 1.58 (0.94–2.07) cm/hr. The Spearman correlation coefficient was 0.438 (P < 0.001) for the overall group. The correlation was strongest in children younger than 4 years (r = 0.537, P = 0.032). Conclusions Although the correlation between BE and CTTRM was not very strong, the 24-hour delayed BE film could provide broad information about colon transit function in young children, especially those under 4 years who usually cannot undergo CTTRM. PMID:26979249

  8. Pattern of 24 hour intragastric acidity in active duodenal ulcer disease and in healthy controls.

    PubMed Central

    Merki, H S; Fimmel, C J; Walt, R P; Harre, K; Röhmel, J; Witzel, L

    1988-01-01

    Twenty four hour intragastric acidity was measured by continuous recording using intragastric combined glass electrodes in 46 duodenal ulcer patients within 48 hours of endoscopic confirmation of active ulceration. Acidity during predefined time periods was compared with that measured in 40 healthy controls without gastrointestinal disease: it was significantly higher in duodenal ulcer patients at all times, but 25% of ulcer patients had median 24 hour acidity within the interquartile range of the normal group. During the evening (18,00 to 22,00 h) ulcer patients had considerable acidity with a median of 39.8 (63.1-31.6) mmol/l (interquartile range) compared with 5.6 (22.3-0.4) mmol/l of controls. It is suggested that antisecretory treatment be directed to decrease this period of unbuffered acidity, as well as during the night, which is presently considered of prime importance. PMID:3209116

  9. A comparison between 24-hour and 2-hour urine collection for the determination of proteinuria.

    PubMed

    Somanathan, N; Farrell, T; Galimberti, A

    2003-07-01

    Proteinuria is one of the fundamental criteria for the diagnosis of pre-eclampsia with quantitative assessment based on the 24-hour urine protein estimation as the gold standard. This study was undertaken to determine whether a 2-hour protein estimation correlated with that of a formal 24-hour collection. Thirty women with proteinuric hypertension were recruited. There was significant correlation between the 2-hour and 24-hour urine protein levels (Pearson's correlation coefficient 0.76 (P 0.000). A positive 2-hour test was associated more closely with significant levels of 24-hour proteinuria than dipstick analysis alone. We conclude from this study that a random 2-hour sample could be used for the initial assessment of proteinuria and so avoid the delay associated with 24-hour quantification of urinary protein. PMID:12881076

  10. Recruiting Strategy and 24-Hour Biomonitoring of Paraquat in Agricultural Workers

    PubMed Central

    Park, Eun-Kee; Tagles, Hector Duarte; Gee, Shirley J.; Hammock, Bruce D.; Lee, Kiyoung; Schenker, Marc B.

    2010-01-01

    The objectives of this study were to recruit agricultural workers in Costa Rica to participate in a 24-hour urine collection for paraquat exposure assessment and to compare the 24-hour sampling to end-of-shift sampling. The authors recruited 187 handlers and 54 nonhandlers from coffee, banana, and palm oil plantations. The completeness of 24-hour urine samples collected (a total of 393 samples) was confirmed by questionnaire and urinary creatinine level. For a subset of 12 samples, the absorbed paraquat level was determined in 24-hours and end-of-shift spot urine samples. The participation rate for handlers was ~90%. The completeness of 24-hour urine collections was verified as the overall average of creatinine levels from 393 urines (1.11 ± 0.50 g/L). A total of 92.4% to 96.7% of urine samples were considered within the acceptable range of urinary creatinine, whereas 94.7% of the samples were described as “complete” from the questionnaire. Measured creatinine correlated well to predicted values (r = .327, p = .0024, 95% CI .12–.51). Detected paraquat levels in spot urine samples had a sensitivity of 96.9% at the high specificity of 100% compared to 24-hour urine samples as the gold standard. There was a significant (p < .0001) correlation between spot and 24-hour urine paraquat levels (r = .7825, 95% CI .61–.88). The recruiting strategy was successful in getting 24-hour urine samples from a farm worker population. Comparison between the paraquat levels in spot and 24-hour urine samples demonstrated that for this compound, end-of-shift spot urine samples would be an appropriate substitute for 24-hour collections. PMID:19064412

  11. A 24-hour remote surveillance system for terrestrial wildlife studies

    USGS Publications Warehouse

    Sykes, P.W., Jr.; Ryman, W.E.; Kepler, C.B.; Hardy, J.W.

    1995-01-01

    The configuration, components, specifications and costs of a state-of-the-art closed-circuit television system with wide application for wildlife research and management are described. The principal system components consist of color CCTV camera with zoom lens, pan/tilt system, infrared illuminator, heavy duty tripod, coaxial cable, coaxitron system, half-duplex equalizing video/control amplifier, timelapse video cassette recorder, color video monitor, VHS video cassettes, portable generator, fuel tank and power cable. This system was developed and used in a study of Mississippi sandhiIl Crane (Grus canadensis pratensis) behaviors during incubation, hatching and fledging. The main advantages of the system are minimal downtime where a complete record of every event, its time of occurrence and duration, are permanently recorded and can be replayed as many times as necessary thereafter to retrieve the data. The system is particularly applicable for studies of behavior and predation, for counting individuals, or recording difficult to observe activities. The system can be run continuously for several weeks by two people, reducing personnel costs. This paper is intended to provide biologists who have litte knowledge of electronics with a system that might be useful to their specific needs. The disadvantages of this system are the initial costs (about $9800 basic, 1990-1991 U.S. dollars) and the time required to playback video cassette tapes for data retrieval, but the playback can be sped up when litte or no activity of interest is taking place. In our study, the positive aspects of the system far outweighed the negative.

  12. Nutrition habits in 24-hour mountain bike racers.

    PubMed

    Chlíbková, Daniela; Knechtle, Beat; Rosemann, Thomas; Tomášková, Ivana; Chadim, Vlastimil; Shortall, Marcus

    2014-01-01

    We investigated seventy-four ultra-mountain bikers (MTBers) competing in the solo category in the first descriptive field study to detail nutrition habits and the most common food before during and after the 24 hour race using questionnaires. During the race, bananas (86.5%), energy bars (50.0%), apples (43.2%) and cheese (43.2%) were the most commonly consumed food, followed by bread (44.6%), rice (33.8%) and bananas (33.8%) after the race. Average fluid intake was 0.5 ± 0.2 l/h. The main beverage was isotonic sports drink (82.4%) during and pure water (66.2%) after the race. The most preferred four supplements in the four weeks before, the day before, during and after the race were vitamin C (35.1%), magnesium (44.6%), magnesium (43.2%) and branched-chain amino acids (24.3%), respectively. Total frequency of food intake (30.6 ± 10.5 times/24 hrs) was associated with fluid intake (r = 0.43, P = 0.04) and both were highest at the beginning of the race and lower during the night hours and the last race segment in a subgroup of twenty-three ultra-MTBers. Supplement intake frequency (6.8 ± 8.4 times/24 hrs) was highest during the night hours and lower at the beginning and end of the race. Elevated food and fluid intake among participants tracked across all race segments (P < 0.001). In conclusion, the nutrition strategy employed by ultra-MTBers was similar to those demonstrated in previous studies of ultra-cyclists with some exceptions among selected individuals. PMID:25674455

  13. 24-hour evaluation of dental plaque bacteria and halitosis after consumption of a single placebo or dental treat by dogs.

    PubMed

    Jeusette, Isabelle C; Román, Aurora Mateo; Torre, Celina; Crusafont, Josep; Sánchez, Nuria; Sánchez, Maria C; Pérez-Salcedo, Leire; Herrera, David

    2016-06-01

    OBJECTIVE To determine whether consumption of a single dental treat with specific mechanical properties and active ingredients would provide a 24-hour effect on dental plaque bacteria and halitosis in dogs. ANIMALS 10 dogs of various breeds from a privately owned colony that had received routine dental scaling and polishing 4 weeks before the study began. PROCEDURES Dogs were randomly assigned to receive 1 placebo or dental treat first. A 4-week washout period was provided, and then dogs received the opposite treatment. Oral plaque and breath samples were collected before and 0.5, 3, 12, and 24 hours after treat consumption. Volatile sulfur compounds (VSCs) concentration was measured in breath samples. Total aerobic, total anaerobic, Porphyromonas gulae, Prevotella intermedia-like, Tannerella forsythia, and Fusobacterium nucleatum bacterial counts (measured via bacterial culture) and total live bacterial counts, total live and dead bacterial counts, and bacterial vitality (measured via quantitative real-time PCR assay) were assessed in plaque samples. RESULTS Compared with placebo treat consumption, dental treat consumption resulted in a significant decrease in breath VSCs concentration and all plaque bacterial counts, without an effect on bacterial vitality. Effects of the dental treat versus the placebo treat persisted for 12 hours for several bacterial counts and for 24 hours for breath VSCs concentration. CONCLUSIONS AND CLINICAL RELEVANCE Although clinical benefits should be investigated in larger scale, longer-term studies, results of this study suggested that feeding the evaluated dental treat may help to decrease oral bacterial growth in dogs for 12 hours and oral malodor for 24 hours. A feeding interval of 12 hours is therefore recommended. PMID:27227499

  14. Comparing food intake using the Dietary Risk Assessment with multiple 24-hour dietary recalls and the 7-Day Dietary Recall.

    PubMed

    Olendzki, B; Hurley, T G; Hebert, J R; Ellis, S; Merriam, P A; Luippold, R; Rider, L; Ockene, I S

    1999-11-01

    The Dietary Risk Assessment (DRA) is a brief dietary assessment tool used to identify dietary behaviors associated with cardiovascular disease. Intended for use by physicians and other nondietitians, the DRA identifies healthful and problematic dietary behaviors and alerts the physician to patients who require further nutrition counseling. To determine the relative validity of this tool, we compared it to the 7-Day Dietary Recall (an instrument developed to assess intake of dietary fat) and to the average of 7 telephone-administered 24-hour dietary recalls. Forty-two free-living subjects were recruited into the study. The 7-Day Dietary Recall and DRA were administered to each subject twice, at the beginning and the end of the study period, and the 24-hour recalls were conducted during the intervening time period. Correlation coefficients were computed to compare the food scores derived from the 3 assessment methods. Correlations between the DRA and 7-Day Dietary Recall data were moderate (r = .47, on average, for postmeasures); correlations between the DRA and 24-hour recalls were lower. The ability of the DRA to assess dietary fat consumption and ease of administration make it a clinically useful screening instrument for the physician when counseling patients about dietary fat reduction. PMID:10570682

  15. Flow cytometric comparison of platelets from a whole blood and finger-prick sample: impact of 24 hours storage.

    PubMed

    Swanepoel, Albe C; Stander, Andre; Pretorius, Etheresia

    2013-03-01

    In this study, we investigate the validity and laboratory utility of flow cytometry when analyzing platelet activation by studying CD41, CD42b, CD62P and CD63. We compare flow cytometry results from citrated whole-blood and finger-prick samples directly after collection and also after storing both a finger-prick and whole-blood sample for 24 hours. Citrated whole-blood and finger-prick samples were taken from three healthy individuals on two occasions, and a total of 60,000 cells were analyzed for each of the four phycoerythrin-labeled monoclonal antibodies. Half of each sample was analyzed immediately after sampling while the other half was kept in the fridge at 6 °C for 24 hours before analysis. No significant difference was found between the sampling methods or the period of time before analysis. Results therefore suggest that an appropriately prepared finger-prick sample can be used for platelet function analysis, and samples can be stored for 24 hours in the fridge at 6 °C before analysis. PMID:23320994

  16. Non-24-Hour Sleep-Wake Disorder Revisited – A Case Study

    PubMed Central

    Garbazza, Corrado; Bromundt, Vivien; Eckert, Anne; Brunner, Daniel P.; Meier, Fides; Hackethal, Sandra; Cajochen, Christian

    2016-01-01

    The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S), which rises linearly during the day, and a circadian process C, which determines the timing of sleep in a ~24-h rhythm in accordance to the external light–dark (LD) cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the suprachiasmatic nucleus (“master clock”) of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau) of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli (“zeitgebers”), the most important being the LD cycle. Misalignments of the internal rhythm with the LD cycle can lead to various somatic complaints and to the development of circadian rhythm sleep disorders (CRSD). Non-24-hour sleep-wake disorders (N24HSWD) is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau > 24.5 h) to the LD cycle. The disease is rare in sighted individuals and the pathophysiology less well understood. Here, we present the case of a 40-year-old sighted male, who developed a misalignment of the internal clock with the external LD cycle following the treatment for Hodgkin’s lymphoma (ABVD regimen, four cycles and AVD regimen, four cycles). A thorough clinical assessment, including actigraphy, melatonin profiles and polysomnography led to the diagnosis of non-24-hour sleep-wake disorders (N24HSWD) with a free-running rhythm of tau = 25.27 h. A therapeutic intervention with bright light therapy (30 min, 10,000 lux) in the morning and melatonin administration (0.5–0.75 mg) in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more intense therapy

  17. Non-24-Hour Sleep-Wake Disorder Revisited - A Case Study.

    PubMed

    Garbazza, Corrado; Bromundt, Vivien; Eckert, Anne; Brunner, Daniel P; Meier, Fides; Hackethal, Sandra; Cajochen, Christian

    2016-01-01

    The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S), which rises linearly during the day, and a circadian process C, which determines the timing of sleep in a ~24-h rhythm in accordance to the external light-dark (LD) cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the suprachiasmatic nucleus ("master clock") of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau) of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli ("zeitgebers"), the most important being the LD cycle. Misalignments of the internal rhythm with the LD cycle can lead to various somatic complaints and to the development of circadian rhythm sleep disorders (CRSD). Non-24-hour sleep-wake disorders (N24HSWD) is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau > 24.5 h) to the LD cycle. The disease is rare in sighted individuals and the pathophysiology less well understood. Here, we present the case of a 40-year-old sighted male, who developed a misalignment of the internal clock with the external LD cycle following the treatment for Hodgkin's lymphoma (ABVD regimen, four cycles and AVD regimen, four cycles). A thorough clinical assessment, including actigraphy, melatonin profiles and polysomnography led to the diagnosis of non-24-hour sleep-wake disorders (N24HSWD) with a free-running rhythm of tau = 25.27 h. A therapeutic intervention with bright light therapy (30 min, 10,000 lux) in the morning and melatonin administration (0.5-0.75 mg) in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more intense therapy might have

  18. Importance of all movement behaviors in a 24 hour period for overall health.

    PubMed

    Chaput, Jean-Philippe; Carson, Valerie; Gray, Casey E; Tremblay, Mark S

    2014-12-01

    Physical inactivity and childhood obesity are well-recognized public health concerns that are associated with a range of adverse health outcomes. Historically, the benefits of physical activity (e.g., moderate-to-vigorous physical activity-MVPA) to overall health have dominated discussions and emerging evidence indicates that a broader, more integrated approach is needed to better understand and address current public health crises. Existing guidelines for children and youth around the world only focus on MVPA, and recently sedentary behavior, despite an accumulating body of evidence showing that light-intensity physical activity (LPA) such as walking can provide important health benefits. Furthermore, there is accumulating support for the importance of adequate sleep and that these behaviors moderate the health impact of each other. Ignoring the other components of the movement continuum (i.e., sleep, sedentary time, LPA) while focusing efforts exclusively on MVPA (accounting for <5% of the time in a 24 h period) limits the potential to optimize the health benefits of movement behaviors. In order to address this limitation, experts in Canada are currently developing the world's first Integrated 24 Hour Movement Behaviour Guidelines for Children and Youth to help advance an integrated healthy active living agenda that has the potential to significantly improve the overall health and well-being of children and youth. PMID:25485978

  19. Obtaining liver tridimensional scaffold through the decellularization of rabbit whole liver in 24 hours

    NASA Astrophysics Data System (ADS)

    Federico, Schliamser; Ayelen, Rinaldi; Romina, Comin; Alba Nelly, Borchert; Adrian, Nari Gustavo; Alicia, Salvatierra Nancy; Mariana Paula, Cid

    2016-04-01

    In the present work, we development a new protocol for liver decellularization in which the hole decellularization was reached over 24 h. Introduction: the availability of transplantable livers is not sufficient to fulfill the current demand for grafts, with the search for therapeutic alternatives having generated different lines of research, one of which is the use of decellularized three-dimensional biological matrices and subsequent cell seeding to obtain a functional organ. Objective: to produce a decellularization protocol from rabbit liver to generate a three-dimensional matrixin which the time period involved didn't pass 24 h. Methods: The decellularization is obtained through the use of water and SDS (0,1-0,3 %), after freezing at -80 degrees, is the best alternative of different physical and/or chemical mechanisms to break down organ cells and leave only the extracellular matriz. After 24 h of retrograde perfusion, a decellularized translucent matrix was generated. To evaluate if the decellularization protocol was successful, with the extracellular matrix being preserved, we carried out histological (light microscopy) and biochemical (DNA quantification) studies. Results: the decellularization process was verified by macroscopic observation of the organ using microscopic observation corroborated the macroscopic results, with the hematoxylin-eosin and Masson staining showing no cells or nuclear material. In addition, the DNA quantification was less than 10% in the decellularized liver compared to control. Finally,the time taken to develop the decellularization protocol was less than 24 hours.

  20. Continuous 24 hour ambulatory monitoring of intragastric pH in man.

    PubMed

    Kapur, B K; Howlett, P J; Kenyon, N G; Lunt, M J; Mills, J G; Smallwood, R H; Wilson, A J; Bardhan, K D

    1987-05-01

    A system has been developed which permits continuous 24 hour ambulatory recording of intragastric pH under near-physiological conditions. The system utilises a Cecar combination pH electrode connected through a pre-amplifier to an Oxford Medical Systems Medilog 4-24 cassette recorder, and the pH recorded continuously on to tape. The data is replayed at high speed, digitised and then analysed. Sources of error included system drift, system noise and the effect of changes in electrode environment due to saliva, food, loss of fluid contact, temperature variations and electrode time constant. These were found to be small. In contrast, the major changes in pH detected reflect real changes at the electrode tip. These changes can be recorded by the system. Developments in electronics and improvements in both the size and quality of pH electrodes, over the past few decades, has enabled intragastric pH recordings to be made with greater ease. However, a large number of investigators still assess gastric acidity by infrequent, intermittent sampling of gastric secretion through a naso-gastric tube. This new ambulatory system is a significant improvement and its versatility allows studies in acid secretion physiology, pharmacology and pathophysiology. PMID:3595080

  1. Electrodes for 24 hours pH monitoring--a comparative study.

    PubMed

    McLauchlan, G; Rawlings, J M; Lucas, M L; McCloy, R F; Crean, G P; McColl, K E

    1987-08-01

    Three pH electrodes in clinical use were examined--(1) antimony electrode with remote reference electrode (Synectics 0011), (2) glass electrode with remote reference electrode (Microelectrodes Inc. MI 506) and (3) combined glass electrode with integral reference electrode (Radiometer GK2801C). In vitro studies showed that both glass electrodes were similar and superior to the antimony electrode with respect to response time, drift, and sensitivity. The effect of the siting of the reference electrode on the recorded pH was examined in five human volunteers. The pH reading using a remote skin reference electrode was higher by a mean of 0.3 pH units (range 0.0-0.6) in the stomach, lower by 0.65 pH units (0.5-0.8) in the duodenum and lower by 0.3 pH units (0.0-0.6) in the oesophagus than that simultaneously obtained with an intraluminal reference electrode. Buccal reference electrodes gave similar readings to skin. Combined reference and glass pH electrodes are recommended for 24-hour ambulatory pH monitoring. PMID:3666560

  2. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust waits for launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In the late morning light at Launch Pad 17-A, Cape Cananveral Air Station, the fixed utility tower (right) casts a long shadow across the base of the Boeing Delta II rocket (left) waiting to launch the Stardust spacecraft. After a 24-hour scrub, the new targeted launch time is 4:04 p.m. EST. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  3. [Ambulatory 24-hour blood pressure monitoring in patients with resistant hypertension].

    PubMed

    Sznajderman, M; Popławska, W; Cybulska, I; Niegowska, J; Makowiecka-Cieśla, M; Baranowski, R

    1990-01-01

    The aim of the study was to assess the usefulness of 24-hour blood pressure (BP) and heart rate (HR) monitoring in patients with "resistant" hypertension. 30 patients (44.1 +/- 9.9 years) with diastolic BP 100 mm Hg or more in spite of treatment with three or more antihypertensive drugs were studied. Ambulatory recording of BP and HR was performed by means of Del Mar Avionics monitoring system 9000. Mean recording time was 21.5 hours and mean number of measurements during one recording--56.7. Mean ambulatory systolic and diastolic BP values were significantly lower than mean value of three casual measurements (146.0 +/- 24.6 vs 171.5 +/- 21.2 mm Hg for systolic and 97.2 +/- 11.3 vs 110.4 +/- 7.5 mm Hg for diastolic BP p less than 0.01) In 14 (46.6%) systolic BP and in 10 patients (33.3%) diastolic BP were normal. The patients with normal and abnormal ambulatory BP recordings did not differ in regard to age and mean clinic BP levels. However, patients with abnormal ambulatory BP recordings were more often overweight and showed a greater frequency of left ventricular hypertrophy and family history of hypertension and its complications. The results of the study show that ambulatory BP monitoring may be of value in assessing the response to antihypertensive treatment in patients with so called resistant hypertension as judged on the basis of clinic pressure. PMID:2074634

  4. The Road Ahead to Continuous 24-Hour Intraocular Pressure Monitoring in Glaucoma

    PubMed Central

    Mansouri, Kaweh

    2014-01-01

    Intraocular pressure (IOP) is the only treatable risk factor for glaucoma. Yet, current glaucoma management usually relies on single IOP measurements during clinic hours despite the fact that IOP is a dynamic parameter with individual rhythms. Single IOP measurements underpin all major clinical guidelines on treatment of glaucoma. Other potentially informative parameters, such as IOP fluctuations and peak IOP, have been neglected, and effects of IOP-lowering interventions on such measures are largely unknown. The search for continuous 24-hour IOP monitoring started over 50 years ago, but only recent technological advances have provided clinician-researchers with devices for continuous IOP monitoring. Herein, we discuss innovative approaches with permanent and temporary devices for 24-hour IOP monitoring, such as a contact lens sensor. Despite being in their infancy, these devices may soon enable clinicians to use 24-hour IOP data to improve glaucoma management and reduce the glaucoma-related burden of disease. PMID:25279129

  5. Microtensile bond strength of resin-resin interfaces after 24-hour and 2-month soaking.

    PubMed

    Leavitt, Curry; Boberick, Kenneth G; Winkler, Sheldon

    2007-01-01

    Evaluate the bond strengths of denture base-repair materials to minimize recurrent failure rate. Use microtensile bond strength (muTBS) testing to evaluate the interfacial bonding strength of 6 commercial denture repair materials after 24-hour and 12-month soaking. Blocks of poly(methyl metacrylate) (PMMA) and Triad were fabricated, fractured, and repaired. Twenty bars (1 x 1 x 30 mm) per group were sectioned from each block parallel to the long axis and approximately 90 degrees to the resin-resin repair interface and stored before muTBS testing in a servo-hydraulic tensile-testing machine. Intact PMMA and Triad bars that had been soaked for 24 hours and 12 months were tested for reference. The 24-hour repair strengths for PMMA ranged from 52% to 84% of original strength. Soaking for 12 months resulted in a 20% decrease in strength for the PMMA control. The 12-month repair strengths for PMMA ranged from 43% to 74% of the 12-month soaked material strength. Triad repair tested 35% of original strength after soaking for 24 hours. Permabond (cyanoacrylate) to PMMA tested 47% of original strength after 24 hours of soaking and 26% of the 12-month soaked material strength. Permabond to Triad tested 30% of original strength after 24 hours of soaking. Permabond and Triad showed a 100% adhesive mode of failure. All other materials tested exhibited either an adhesive mode of failure at the denture base-repair-material interface or a complex cohesive failure within the repair-material interface. The muTBS approach can be used to analyze the resin-resin interface of repaired acrylics. The relatively small standard deviations make the muTBS approach attractive. In this study, muTBS was used to evaluate the repair strength of 6 denture repair materials enabling clinicians to make clinical judgments regarding the strongest repair bond available. PMID:17987865

  6. Arrhythmias Seen in Baseline 24-Hour Holter ECG Recordings in Healthy Normal Volunteers During Phase 1 Clinical Trials.

    PubMed

    Hingorani, Pooja; Karnad, Dilip R; Rohekar, Prashant; Kerkar, Vaibhav; Lokhandwala, Yash Y; Kothari, Snehal

    2016-07-01

    Regulatory agencies encourage sponsors to submit 24-hour ambulatory ECG data for assessing cardiac safety of new drugs, and some arrhythmias, hitherto considered rare, have been observed in some early-phase studies. Interpretation of these observations is difficult given the dearth of published data on the prevalence of cardiac arrhythmias seen during 24-hour continuous ECG monitoring in healthy volunteers (HV) from clinical trials. We analyzed drug-free ambulatory ECG recordings from 1273 HV (1000 males, 273 females; age 18-65 years) from 22 phase 1 studies that were analyzed in a core ECG laboratory; all subjects had normal screening ECGs. Supraventricular arrhythmias such as supraventricular premature complexes were observed in 60.8% of healthy volunteers, supraventricular tachycardia in 2.2%, and atrial fibrillation in 0.1%. Ventricular arrhythmias included premature ventricular complexes (PVCs) in 43.4%, >200 PVCs per 24 hours in 3.3%, multifocal PVCs in 5.3%, nonsustained ventricular tachycardia in 0.7%, and accelerated idioventricular rhythm in 0.3%. Bradyarrhythmias included sinus pause >3 seconds in 0.3%, and second-degree AV block in 2.4%. Complete heart block and torsades de pointes were not seen in any subject. Based on the observed incidence, we estimated the maximum number of healthy subjects in whom these arrhythmias may be seen as a matter of chance in studies with smaller sample sizes if the study drug has no arrhythmogenic effect. Our results and these estimates could help interpret whether cardiac arrhythmias observed in early-phase studies are due to chance or possibly are a drug effect. PMID:26626443

  7. Caffeine does not entrain the circadian clock but improves daytime alertness in blind patients with non-24-hour rhythms

    PubMed Central

    St. Hilaire, Melissa A.; Lockley, Steven W.

    2015-01-01

    Objective/Background Totally blind individuals are highly likely to suffer from Non-24-Hour Sleep-Wake Disorder due to a failure of light to reset the circadian pacemaker in the suprachiasmatic nuclei. In this outpatient case series, we investigated whether daily caffeine administration could entrain the circadian pacemaker in non-entrained blind patients to alleviate symptoms of non-24-hour sleep–wake disorder. Patients/Methods Three totally blind males (63.0 ± 7.5 years old) were studied at home over ~4 months. Urinary 6-sulphatoxymelatonin (aMT6s) rhythms were measured for 48 h every 1–2 weeks. Participants completed daily sleep–wake logs, and rated their alertness and mood using nine-point scales every ~2–4 h while awake on urine sampling days. Caffeine capsules (150 mg per os) were self-administered daily at 10 a.m. for approximately one circadian beat cycle based on each participant's endogenous circadian period τ and compared to placebo (n = 2) or no treatment (n = 1) in a single-masked manner. Results Non-24-h aMT6s rhythms were confirmed in all three participants (τ range = 24.32–24.57 h). Daily administration of 150 mg caffeine did not entrain the circadian clock. Caffeine treatment significantly improved daytime alertness at adverse circadian phases (p < 0.0001) but did not decrease the occurrence of daytime naps compared with placebo. Conclusions Although caffeine was able to improve daytime alertness acutely and may therefore provide temporary symptomatic relief, the inability of caffeine to correct the underlying circadian disorder means that an entraining agent is required to treat Non-24-Hour Sleep–Wake Disorder in the blind appropriately. PMID:25891543

  8. Oropharyngeal 24-Hour pH Monitoring in Children With Airway-Related Problems

    PubMed Central

    Mesallam, Tamer A.

    2016-01-01

    Objectives Diagnosis and clinical presentation of pediatric laryngopharyngeal reflux (LPR) is still controversial. The aims of this work were to study the possibility of performing 24-hour oropharyngeal pH monitoring for children in the outpatient clinic setup and to explore the results of this test in correlation to airway-related problems. Methods In this descriptive qualitative study, 26 children suffering from airway-related problems were included. Oropharyngeal 24-hour pH monitoring was performed for all subjects in the outpatient clinic setting. The distribution of airway diagnoses among the study group was studied versus the results of the pH monitoring. Results There were 16 males and 10 females participated in the study with a mean age of 6.88 (SD, ±5.77) years. Thirty-five percent of the patients were under the age of 3 years (range, 11 months to 3 years). Eight-five percent of the patients tolerated the pH probe insertion and completed 24-hour of pH recording. Laryngomalacia and subglottic stenosis (SGS) were more frequently reported in the positive LPR patients (77%). Conclusion Oropharyngeal 24-hour pH monitoring can be conducted for children in the outpatient setup even in young age children below 3 years old. Among the positive LPR group, SGS and laryngomalacia were the most commonly reported airway findings. PMID:27090271

  9. Assessing dietary intake in childhood cancer survivors: Food frequency questionnaire versus 24-hour diet recalls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet r...

  10. 24-Hour Access: Responding to Students' Need for Late Library Hours at the University of Denver

    ERIC Educational Resources Information Center

    Sewell, Bethany B.

    2013-01-01

    The University of Denver's Penrose Library saw a substantial increase in use as a result of several new and enhanced services over a six-year period. In turn, longer operating hours and increased staffing for a 24-hours-a-day, five-days-a-week (24 x 5) operating schedule was funded. This case study analyzes student need for longer library hours…

  11. Mood-Dependent Cognitive Change in a Man with Bipolar Disorder Who Cycles Every 24 Hours

    ERIC Educational Resources Information Center

    Lam, Dominic; Mansell, Warren

    2008-01-01

    A case study of a bipolar patient whose mood changes every 24 hours is described to illustrate the changes in cognitive processing and content during different phases of bipolar disorder. The participant completed a battery of questionnaires and tasks on 4 separate occasions: twice when depressed and twice when manic. Depression tended to be…

  12. Sleep-Disordered Breathing and 24-Hour Blood Pressure Pattern Among Older Adults

    PubMed Central

    White, William B.; Kutner, Michael; Ouslander, Joseph G.; Bliwise, Donald L.

    2009-01-01

    Background To examine the association between sleep-disordered breathing (SDB) and 24-hour blood pressure (BP) pattern among community-dwelling older adults. Methods A convenience sample of 70 community-dwelling older adults, recruited from senior housing, community centers, and learning centers, were admitted to General Clinical Research Center, Emory University Hospital, Atlanta, Ga. Information regarding demographic and clinical history was obtained using questionnaires. Twenty-four–hour BP monitoring in supine position was performed using Spacelabs model 20207. Breathing during sleep was monitored with the use of a modified sleep recording system (Embletta, PDS), which monitors nasal and oral airflow, chest and abdominal movements, and pulse oximetry. Night time–daytime (night-day) BP ratio (average night-time BP divided by daytime BP) was calculated both for systolic and diastolic BPs. Results Sixty-nine participants, mean age 74.9 ± 6.4 years (41 [57%] women), completed the study. The mean apnea-hypopnea index (AHI) was 13 ± 13 per hour of sleep, and 20 participants (29%) had AHI ≥15 per hour of sleep, indicating moderate to severe SDB. Moderate to severe SDB (AHI ≥15 per hour of sleep) was significantly associated with nocturnal hypertension, whereas there was no statistically significant difference in wake-time BP between those with and without moderate to severe SDB. Stepwise multiple regressions showed that AHI independently predicted increased night-day systolic and night-day diastolic BP ratio, even after controlling for nocturia frequency. Conclusions The results indicate increased BP load associated with increased AHI in this group of older adults. This increased BP load may contribute to increased hypertension-related morbidity and disease burden. PMID:19196901

  13. Usability of a smartphone food picture app for assisting 24-hour dietary recall: a pilot study

    PubMed Central

    Pope, Benjamin T.; Bilgiç, Pelin; Orr, Barron J.; Suzuki, Asuka; Kim, Angela Sarah; Merchant, Nirav C.; Roe, Denise J.

    2015-01-01

    BACKGROUND/OBJECTIVES The Recaller app was developed to help individuals record their food intakes. This pilot study evaluated the usability of this new food picture application (app), which operates on a smartphone with an embedded camera and Internet capability. SUBJECTS/METHODS Adults aged 19 to 28 years (23 males and 22 females) were assigned to use the Recaller app on six designated, nonconsecutive days in order to capture an image of each meal and snack before and after eating. The images were automatically time-stamped and uploaded by the app to the Recaller website. A trained nutritionist administered a 24-hour dietary recall interview 1 day after food images were taken. Participants' opinions of the Recaller app and its usability were determined by a follow-up survey. As an evaluation indicator of usability, the number of images taken was analyzed and multivariate Poisson regression used to model the factors determining the number of images sent. RESULTS A total of 3,315 food images were uploaded throughout the study period. The median number of images taken per day was nine for males and 13 for females. The survey showed that the Recaller app was easy to use, and 50% of the participants would consider using the app daily. Predictors of a higher number of images were as follows: greater interval (hours) between the first and last food images sent, weekend, and female. CONCLUSIONS The results of this pilot study provide valuable information for understanding the usability of the Recaller smartphone food picture app as well as other similarly designed apps. This study provides a model for assisting nutrition educators in their collection of food intake information by using tools available on smartphones. This innovative approach has the potential to improve recall of foods eaten and monitoring of dietary intake in nutritional studies. PMID:25861429

  14. Aldosterone-to-Renin Ratio Is Associated With Reduced 24-Hour Heart Rate Variability and QTc Prolongation in Hypertensive Patients

    PubMed Central

    Grübler, Martin R.; Kienreich, Katharina; Gaksch, Martin; Verheyen, Nicolas; Hartaigh, Bríain Ó.; Fahrleitner-Pammer, Astrid; März, Winfried; Schmid, Johannes; Oberreither, Eva-Maria; Wetzel, Julia; Catena, Cristiana; Sechi, Leonardo A.; Pieske, Burkert; Tomaschitz, Andreas; Pilz, Stefan

    2016-01-01

    Abstract Aldosterone is considered to exert direct effects on the myocardium and the sympathetic nervous system. Both QT time and heart rate (HR) variability (HRV) are considered to be markers of arrhythmic risk and autonomous dysregulation. In this study, we investigated the associations between aldosterone, QT time, and HRV in patients with arterial hypertension. We recruited 477 hypertensive patients (age: 60.2 ± 10.2 years; 52.3% females) with a mean systolic/diastolic 24-hour ambulatory blood pressure monitoring (ABPM) value of 128 ± 12.8/77.1 ± 9.2 mmHg and with a median of 2 (IQR: 1–3) antihypertensive agents. Patients were recruited from the outpatient clinic at the Department of Internal Medicine of the Medical University of Graz, Austria. Blood samples, 24-hour HRV derived from 24-hour blood pressure monitoring (ABPM) and ECG's were obtained. Plasma aldosterone and plasma renin concentrations were measured by means of a radioimmunoassay. Twenty-four-hour urine specimens were collected in parallel with ABPM. Mean QTc was 423.3 ± 42.0 milliseconds for males and 434.7 ± 38.3 milliseconds for females. Mean 24H-HR and 24H-HRV was 71.9 ± 9.8 and 10.0 ± 3.6 bpm, respectively. In linear regression analyses adjusted for age, sex, body mass index, ABPM, and current medication, aldosterone to active renin ratio (AARR) was significantly associated with the QTc interval, a marker for cardiac repolarization abnormalities (mean = 426 ± 42.4 milliseconds; β-coefficient = 0.121; P = 0.03) as well as with the 24-hour heart rate variability a surrogate for autonomic dysfunction (median = 9.67 [IQR = 7.38–12.22 bpm]; β-coefficient = −0.133; P = 0.01). In hypertensive patients, AARR is significantly related to QTc prolongation as well as HRV. Further studies investigating the effects of mineralocorticoid receptor blocker and aldosterone synthase inhibitors on QTc and HRV are warranted

  15. Early Time Points Perfusion Imaging

    PubMed Central

    Kwong, Kenneth K.; Reese, Timothy G.; Nelissen, Koen; Wu, Ona; Chan, Suk-Tak; Benner, Thomas; Mandeville, Joseph B.; Foley, Mary; Vanduffel, Wim; Chesler, David A.

    2010-01-01

    The aim was to investigate the feasibility of making relative cerebral blood flow (rCBF) maps from MR images acquired with short TR by measuring the initial arrival amount of Gd-DTPA evaluated within a time window before any contrast agent has a chance to leave the tissue. We named this rCBF measurement technique utilizing the early data points of the Gd-DTPA bolus the “early time points” method (ET), based on the hypothesis that early time point signals were proportional to rCBF. Simulation data were used successfully to examine the ideal behavior of ET while monkey’s MRI results offered encouraging support to the utility of ET for rCBF calculation. A better brain coverage for ET could be obtained by applying the Simultaneous Echo Refocusing (SER) EPI technique. A recipe to run ET was presented, with attention paid to the noise problem around the time of arrival (TOA) of the contrast agent. PMID:20851196

  16. [24-hour blood pressure measurement in normal pregnancy in hypertensive pregnant patients].

    PubMed

    Rath, W; Schrader, J; Guhlke, U; Buhr-Schinner, H; Haupt, A; Kramer, A; Kuhn, W

    1990-08-01

    Noninvasive 24-hour ambulatory blood pressure monitoring was performed in 17 normotensive and 19 preeclamptic pregnant women. The normotensive women showed a significant nightly decline in their systolic and diastolic blood pressure. In contrast, the preeclamptic women demonstrated either an attenuated circadian rhythm or no circadian rhythm at all. This result was even more pronounced in patients with severe hypertension, some of whom had a nocturnal increase in blood pressure in spite of being treated with antihypertensive drugs in an evening dose. The lack of nocturnal blood pressure decrease was also found 24 hours post partum. In summary, these results suggest that preeclamptic women are endangered by hypertensive emergencies mostly during the night. Therefore blood pressure controls should be extended into the night, and antihypertensive drugs should also be given in a sufficient evening dose. PMID:2214601

  17. Patients in 24-hour home care striving for control and safety

    PubMed Central

    2012-01-01

    Background This article concerns Swedish patients receiving 24-hour home care from health care assistants (HC assistants) employed by the municipality. Home care is a complex interactive process involving the patient, family, HC assistants as well as professional care providers. Previous studies exploring patient perspectives on home care have been based mainly on patient interviews. In contrast, the present study took a broad perspective on patients’ experiences and thoughts by combining field observations on care situations with patient and HC assistant interviews. The aim of the study presented in this article was to promote a new and broadened understanding of patients receiving 24-hour home care by constructing a theoretical model to illuminate their main concern. Methods Field observations and semi-structured interviews were conducted with four patients receiving 24-hour home care and their HC assistants. Grounded theory methodology was used. Results The core process identified was Grasping the lifeline, which describes compensatory processes through which patients strived for control and safe care when experiencing a number of exposed states due to inadequate home care. Patients tried to take control by selecting their own HC assistants and sought safe hands by instructing untrained HC assistants in care procedures. When navigating the care system, the patients maintained contacts with professional care providers and coordinated their own care. When necessary, a devoted HC assistant could take over the navigating role. The results are illuminated in a theoretical model. Conclusions The results accentuate the importance to patients of participating in their own care, especially in the selection of HC assistants. The model illustrates some challenging areas for improvement within the organisation of 24-hour home care, such as personnel continuity and competence, collaboration, and routines for acute care. Furthermore, it may be used as a basis for reflection

  18. Analogue step-by-step DC component eliminator for 24-hour PPG signal monitoring.

    PubMed

    Pilt, Kristjan; Meigas, Kalju; Lass, Jaanus; Rosmann, Mart; Kaik, Jüri

    2007-01-01

    For applications where PPG signal AC component needs to be measured without disturbances in its shape and recorded digitally with high digitalization accuracy, the step-by-step DC component eliminator is developed. This paper describes step-by-step DC component eliminator, which is utilized with analogue comparator and operational amplifier. It allows to record PPG signal without disturbances in its shape in 24-hours PPG signal monitoring system. The experiments with PPG signal have been carried out. PMID:18002130

  19. 24-hour-restraint stress induces long-term depressive-like phenotypes in mice.

    PubMed

    Chu, Xixia; Zhou, Ying; Hu, Zhiqiang; Lou, Jingyu; Song, Wei; Li, Jing; Liang, Xiao; Chen, Chen; Wang, Shuai; Yang, Beimeng; Chen, Lei; Zhang, Xu; Song, Jinjing; Dong, Yujie; Chen, Shiqing; He, Lin; Xie, Qingguo; Chen, Xiaoping; Li, Weidong

    2016-01-01

    There is an increasing risk of mental disorders, such as acute stress disorder (ASD), post-traumatic stress disorder (PTSD) and depression among survivors who were trapped in rubble during earthquake. Such long-term impaction of a single acute restraint stress has not been extensively explored. In this study, we subjected mice to 24-hour-restraint to simulate the trapping episode, and investigated the acute (2 days after the restraint) and long-term (35 days after the restraint) impacts. Surprisingly, we found that the mice displayed depression-like behaviors, decreased glucose uptake in brain and reduced adult hippocampal neurogenesis 35 days after the restraint. Differential expression profiling based on microarrays suggested that genes and pathways related to depression and other mental disorders were differentially expressed in both PFC and hippocampus. Furthermore, the depression-like phenotypes induced by 24-hour-restraint could be reversed by fluoxetine, a type of antidepressant drug. These findings demonstrated that a single severe stressful event could produce long-term depressive-like phenotypes. Moreover, the 24-hour-restraint stress mice could also be used for further studies on mood disorders. PMID:27609090

  20. 24-hour-restraint stress induces long-term depressive-like phenotypes in mice

    PubMed Central

    Zhou, Ying; Hu, Zhiqiang; Lou, Jingyu; Song, Wei; Li, Jing; Liang, Xiao; Chen, Chen; Wang, Shuai; Yang, Beimeng; Chen, Lei; Zhang, Xu; Song, Jinjing; Dong, Yujie; Chen, Shiqing; He, Lin; Xie, Qingguo; Chen, Xiaoping; Li, Weidong

    2016-01-01

    There is an increasing risk of mental disorders, such as acute stress disorder (ASD), post-traumatic stress disorder (PTSD) and depression among survivors who were trapped in rubble during earthquake. Such long-term impaction of a single acute restraint stress has not been extensively explored. In this study, we subjected mice to 24-hour-restraint to simulate the trapping episode, and investigated the acute (2 days after the restraint) and long-term (35 days after the restraint) impacts. Surprisingly, we found that the mice displayed depression-like behaviors, decreased glucose uptake in brain and reduced adult hippocampal neurogenesis 35 days after the restraint. Differential expression profiling based on microarrays suggested that genes and pathways related to depression and other mental disorders were differentially expressed in both PFC and hippocampus. Furthermore, the depression-like phenotypes induced by 24-hour-restraint could be reversed by fluoxetine, a type of antidepressant drug. These findings demonstrated that a single severe stressful event could produce long-term depressive-like phenotypes. Moreover, the 24-hour-restraint stress mice could also be used for further studies on mood disorders. PMID:27609090

  1. [Formula creatinine clearance as a substitute for 24-hour creatine clearance in children with kidney transplantation].

    PubMed

    Aufricht, C; Balbisi, A; Gerdov, C; Müller, T; Lothaller, M A; Balzar, E

    1995-01-01

    Despite many theoretical advantages, formula-creatininclearance (Schwartz et al, Journal of Pediatrics 1976) has not found broad clinical acceptance in everyday pediatric patient care. In this study we report our results of long term observations (11.7 +/- 6.8 (1.7-24.8) months) of measured and computed creatininclearance in 27 children after renal transplantation (15 boys, 12 girls, mean age 14.5 +/- 4.2 (5.5-20) years) at the Kinderdialyse of the Universitäts-Kinderklinik of Vienna. We found a wide scattered correlation between the measured and computed creatininclearance values with a 90% confidence interval between -30% to +60% of the 24 hour creatininclearance. Formula creatininclearance (SD 17.8%) was markedly better reproducable than the 24 hour creatininclearancethe (SD 37.8%), the intraindividuell collecting error (36.1%) was almost twice the interindividuell "coefficient" error (20.27%). We therefore conclude that the 24 hour creatininclearance is by far not as accurate as the complexity of the procedure pretends and support broad clinical acceptance for the formula creatininclearance. PMID:7752601

  2. Impact of diet on 24-hour intragastric pH profile in healthy horses.

    PubMed

    Damkel, Cornelia; Snyder, Alice; Uhlig, Albrecht; Coenen, Manfred; Schusser, Gerald Fritz

    2015-01-01

    An electrode incorporated into a polyethylene hose was introduced under endoscopic control into the stomach of six fasting adult horses for long-lasting pH measurements. The intragastric pH was recorded every four seconds for a period of 24 hours. The Warmblood horses were assigned randomly to receive hay ad libitum (H group); 1.5 kg hay/100 kg BW/day and 1 kg concentrate/100 kg BW/ day (C group) or protocol C plus 75 g pectin-lecithin supplement/100 kg BW/day (P group). The horses were adapted to each diet for 14 days. The 24-hour median pH value for protocol H (2.69) was significantly lower compared to protocol C (3.35) and P (3.44) (p < 0.05). The horses in protocol P had a significant higher percentage (40.1 %) of 24-hour intragastric pH values ≥ 4 than in protocol C (36.2 %) or in protocol H (25.3 %) (p < 0.05). PMID:26591378

  3. Characterisation of sleep in intensive care using 24-hour polysomnography: an observational study

    PubMed Central

    2013-01-01

    Introduction Many intensive care patients experience sleep disruption potentially related to noise, light and treatment interventions. The purpose of this study was to characterise, in terms of quantity and quality, the sleep of intensive care patients, taking into account the impact of environmental factors. Methods This observational study was conducted in the adult ICU of a tertiary referral hospital in Australia, enrolling 57 patients. Polysomnography (PSG) was performed over a 24-hour period to assess the quantity (total sleep time: hh:mm) and quality (percentage per stage, duration of sleep episode) of patients' sleep while in ICU. Rechtschaffen and Kales criteria were used to categorise sleep. Interrater checks were performed. Sound pressure and illuminance levels and care events were simultaneously recorded. Patients reported on their sleep quality in ICU using the Richards Campbell Sleep Questionnaire and the Sleep in Intensive Care Questionnaire. Data were summarised using frequencies and proportions or measures of central tendency and dispersion as appropriate and Cohen's Kappa statistic was used for interrater reliability of the sleep data analysis. Results Patients' median total sleep time was 05:00 (IQR: 02:52 to 07:14). The majority of sleep was stage 1 and 2 (medians: 19 and 73%) with scant slow wave and REM sleep. The median duration of sleep without waking was 00:03. Sound levels were high (mean Leq 53.95 dB(A) during the day and 50.20 dB(A) at night) and illuminance levels were appropriate at night (median <2 lux) but low during the day (median: 74.20 lux). There was a median 1.7 care events/h. Patients' mean self-reported sleep quality was poor. Interrater reliability of sleep staging was highest for slow wave sleep and lowest for stage 1 sleep. Conclusions The quantity and quality of sleep in intensive care patients are poor and may be related to noise, critical illness itself and treatment events that disturb sleep. The study highlights the

  4. Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion

    PubMed Central

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-01-01

    Abstract Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286–4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the

  5. Normal values of 24-hour ambulatory esophageal impedance-pH monitoring in a rural South African cohort of healthy participants.

    PubMed

    Ndebia, E J; Sammon, A M; Umapathy, E; Iputo, J E

    2016-05-01

    There are no data on 24-hour multichannel intraluminal impedance and pH monitoring in African populations. The purpose of this study was to provide the normal values of esophageal impedance and pH monitoring in a rural African populations. South African healthy rural participants were recruited and underwent 24 hours of esophageal impedance and pH monitoring. The median and the 95th percentiles of the total reflux episodes were 49 and 97, respectively, of which the corresponding number of acidic, weakly acidic, and weakly alkaline reflux were 15 and 55, 17 and 51, and 8 and 36, respectively. The compositions of the total reflux were 5 and 21 for liquid, 27 and 72 for mixed, and 10 and 39 for gas reflux, respectively. The median bolus clearance was 18 seconds and the median bolus exposure was 14 minutes/24 hours. The proximal extent was 6%. The 95th percent time of esophageal exposure to acid was 8.6 in 24 hours. Female and overweight participants were associated with an increased number of reflux events. There were more reflux episodes, and of which, more were weakly alkaline compared with previous similar studies. The findings provide reference values of gastroesophageal reflux for a South African rural population. PMID:25721534

  6. 77 FR 65310 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... the 2006 24-hour Fine Particle (PM 2.5 ) National Ambient Air Quality Standards,'' 74 FR 58688... Federal Regulations DC District of Columbia EO Executive Order EPA Environmental Protection Agency FR... EPA finalized designations for the 2006 24-hour PM 2.5 NAAQS (74 FR 58688, November 13, 2009), the...

  7. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 4 2014-07-01 2014-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  8. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 4 2013-07-01 2013-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  9. 40 CFR 52.1990 - Interstate Transport for the 2006 24-hour PM2.5 NAAQS.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 4 2012-07-01 2012-07-01 false Interstate Transport for the 2006 24-hour PM2.5 NAAQS. 52.1990 Section 52.1990 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... § 52.1990 Interstate Transport for the 2006 24-hour PM2.5 NAAQS. (a) EPA approves the portion of...

  10. Evaluation of Intradermal and Subcutaneous Infusion Set Performance Under 24-Hour Basal and Bolus Conditions

    PubMed Central

    McVey, Elaine; Keith, Steven; Herr, Joshua K.; Sutter, Diane; Pettis, Ronald J.

    2015-01-01

    Background: This study sought to assess the function and delivery reliability of intradermal (ID) infusion sets used with commercial insulin pumps. Method: Healthy subjects (n = 43) were randomized to either ID or subcutaneous (SC) arms, and received basal/bolus placebo delivery for 24 hours. Subjects received 4 of 8 infusion set combinations (ID: microneedle design A or B, with 2 pump brands [Animas or MiniMed]; SC: Teflon Quickset or steel Rapid-D, Animas pump only, with or without overtaping) and were evaluated for pump occlusion alarms, fluid leakage, pain, and tissue tolerability. A novel algorithm was developed to determine flow consistency based on fluid pressure, and the duration and occurrence rate for periods of unalarmed but interrupted flow (“silent occlusions’”) were compared. Results: ID delivery was successfully maintained over the 24-hour infusion period. The number of silent occlusions was lower for ID microneedle cannula design B than A (P < .01) and lower for Rapid-D SC device compared to Quick-set (P = .03). There was no significant difference in the number of occlusion alarms between the ID and SC devices with the Animas pump. However, the pumps tested with ID devices had significantly different alarm rates (MiniMed 29.5%, Animas 0%, P < .001). Leakage and tissue tolerability were comparable across devices. Conclusion: The ID infusion set reliably delivered diluent for an extended 24-hour period in healthy subjects and was well tolerated. Silent occlusion flow interruptions could be detected in both ID and SC infusion sets using a proprietary algorithm. This algorithm is a promising method for quantitatively evaluating infusion set flow performance. PMID:26319228

  11. Implementation of a 24-Hour Pharmacy Service with Prospective Medication Review in the Emergency Department

    PubMed Central

    Yee, Linda; Claudio-Saez, Maria; Halim, Qazi; Marshall, Lewis; Hayes-Quinn, Mary

    2015-01-01

    Background: It is reported that more than 128 million patients are seen in emergency departments (EDs) annually. Patient overcrowding had been associated with an increased occurrence of medication errors. Purpose: Due to increased patient volume and the need for improved patient safety, a 24-hour pharmacy service was established for our institution’s ED. The purpose of the study is to quantify and demonstrate the impact of a 24-hour pharmacy service in an urban ED. Methods: This was a retrospective descriptive study conducted at a regional level 1 trauma center. The study period occurred between December 2012 and July 2013. The following variables were quantified and analyzed: number of medication orders reviewed, number of intravenous medications compounded, and number of clinical interventions that were recommended by the ED pharmacy team (EDPT) and accepted by ED clinicians. Results: A total of 3,779 medication orders were reviewed by the EDPT. Of these orders, 3,482 (92%) were prospectively reviewed. A total of 3,068 (81.2%) and 711 (18.8%) orders were reviewed for the adult and pediatric ED, respectively. During the study period, the EDPT procured 549 intravenous admixtures and conducted 642 clinical interventions. Most of the interventions involved providing drug information for physicians and nurses (45.9%), adjusting drug dosages (21.1%), and recommending antimicrobial therapy (15.1%). Conclusion: The implementation of a 24-hour pharmacy service at our institution was an innovative practice that increased the role of pharmacists in the ED. The EDPT conducted prospective medication review, procured intravenous admixtures from a sterile environment, and provided therapeutic recommendations for the ED interdisciplinary team. PMID:25717209

  12. Treating allergic conjunctivitis: A once-daily medication that provides 24-hour symptom relief

    PubMed Central

    Schaeffer, Jack; Donnenfeld, Eric

    2016-01-01

    Background: Allergic conjunctivitis (AC) is a common ocular inflammatory manifestation of allergen exposure in sensitized individuals. Signs and symptoms of AC can decrease quality of life, interfere with productivity, and lead to considerable economic burden. Consistent suppression of conjunctival inflammation is necessary for managing AC, but currently available medications require frequent administration and exhibit limited duration of action. Methods: In this review, we summarized AC pathogenesis, diagnosis, and current treatment options as well as their limitations. Findings from the literature were discussed in the context of the unmet need for a once-daily medication with sustained 24-hour effectiveness. Results: Topical pharmacologic treatments are the most common approach for managing extant AC; however, most available medications require multiple daily instillations. Dual-acting antihistamine-mast cell stabilizing agents are currently considered first-line therapeutics for AC because they provide acute relief of signs and symptoms and block persistent inflammation to promote regression of AC. Recent studies of a newly-developed, higher-concentration formulation of a dual-acting antihistamine-mast cell stabilizer have demonstrated that this formulation provides a 24-hour duration of action with once-daily dosing. Conclusions: Dual-acting AC medications exhibit a high degree of overall effectiveness and are well tolerated for chronic use. A newly available once-daily medication that manages signs and symptoms of AC for a full 24 hours may be considered a treatment of choice for patients experiencing seasonal or perennial AC. ClinicalTrials.gov NCT01743027 and NCT01479374 PMID:27466061

  13. Ultra-Rapid dUT1 Measurements on Japan-Fennoscandian Baselines - Application to 24-hour Sessions

    NASA Technical Reports Server (NTRS)

    Matsuzaka, Shigeru; Kurihara, Shinobu; Sekido, Mamoru; Hobiger, Thomas; Haas, Rudiger; Ritakari, Jouko; Wagner, Jan

    2010-01-01

    GSI, NICT, OSO, and MRO have been engaged in Ultra-rapid dUT1 experiments since 2007 aiming at the technological possibility of real-time dUT1 results using the e-VLBI technique. We have already successfully determined dUT1 in less than four minutes after the end of an experimental Intensive session in 2008, and at present we routinely get the results within 30 minutes for regular Intensives. In 2009 we applied the technique to 24-hour sessions and continuously obtained dUT1 values by processing and analyzing Tsukuba Onsala data in near real-time. It showed a detailed behavior of UT1 variations, which could be very valuable for scientific study as well as for precise prediction of UT1-UTC.

  14. Pulse wave velocity 24-hour monitoring with one-site measurements by oscillometry

    PubMed Central

    Posokhov, Igor N

    2013-01-01

    This review describes issues for the estimation of pulse wave velocity (PWV) under ambulatory conditions using oscillometric systems. The difference between the principles of measuring the PWV by the standard method and by oscillometry is shown, and information on device validation studies is summarized. It was concluded that currently oscillometry is a method that is very convenient to use in the 24-hour monitoring of the PWV, is relatively accurate, and is reasonably comfortable for the patient. Several indices with the same principles as those in the analysis of blood pressure in ambulatory monitoring of blood pressure, namely the assessment of load, variability, and circadian rhythm, are proposed. PMID:23549868

  15. Assessing Dietary Intake in Childhood Cancer Survivors: Food Frequency Questionnaire Versus 24-Hour Diet Recalls.

    PubMed

    Zhang, Fang Fang; Roberts, Susan B; Must, Aviva; Wong, William W; Gilhooly, Cheryl H; Kelly, Michael J; Parsons, Susan K; Saltzman, Edward

    2015-10-01

    Cancer diagnosis and treatment may influence dietary intake. The validity of using self-reported methods to quantify dietary intake has not been evaluated in childhood cancer survivors. We validated total energy intake (EI) reported from Food Frequency Questionnaire (FFQ) and repeated 24-hour diet recalls (24HRs) against total energy expenditure (TEE) measured using the doubly labeled water method in 16 childhood cancer survivors. Dietary underreporting, assessed by (EI-TEE)/TEE × 100%, was 22% for FFQ and 1% for repeated 24HRs. FFQ significantly underestimates dietary intake and should not be used to assess the absolute intake of foods and nutrients in childhood cancer survivors. PMID:25883059

  16. Screening for proteinuria in a rheumatology clinic: comparison of dipstick testing, 24 hour urine quantitative protein, and protein/creatinine ratio in random urine samples.

    PubMed

    Ralston, S H; Caine, N; Richards, I; O'Reilly, D; Sturrock, R D; Capell, H A

    1988-09-01

    Measurements of protein/creatinine ratio in 'spot' urine samples were compared with measurements of 24 hour quantitative proteinuria and side room 'dipstick' testing in 104 samples from 90 patients presenting consecutively to a rheumatology unit. Linear regression analysis showed a highly significant correlation between the random urinary protein/creatinine ratio and total protein excretion in 24 hour urine samples (r = 0.92, p less than 0.001, y = 6.55x + 0.04). Although an approximation of 24 hour urinary protein excretion could have been made from the regression line: 24 hour urine protein = 6.55 x protein/creatinine ratio + 0.04 (g/l), there was a wide scatter of values, particularly in patients with greater than 1 g/24 h urinary protein excretion. Nevertheless, significant proteinuria (greater than 300 mg/24 h) could have been confirmed or excluded with a sensitivity and specificity of 97% by adopting random protein/creatinine values of less than 0.04 as 'normal'. Specificity and sensitivity could have been increased to 100%, however, by excluding patients with values lying between 0.01 and 0.10 as all the false negatives (n = 3) and false positives (n = 3) lay within this range. In comparison, dipstick testing, although 100% sensitive, had a poor specificity due to the high false positive rate (40/83 (48%] in patients with 1+ to 3+ readings. Assessment of random urinary protein/creatinine ratio may obviate the need for 24 hour urine collections in the initial assessment of suspected proteinuria. A wider application of this technique seems indicated in view of the obvious advantages in terms of cost, time, and patient convenience. PMID:3263087

  17. A 24-hour Approach to the Study of Health Behaviors: Temporal Relationships between Waking Health Behaviors and Sleep

    PubMed Central

    Irish, Leah A.; Kline, Christopher E.; Rothenberger, Scott D.; Krafty, Robert T.; Buysse, Daniel J.; Kravitz, Howard M.; Bromberger, Joyce T.; Zheng, Huiyong; Hall, Martica H.

    2013-01-01

    Background Although sleep is often associated with waking health behaviors (WHB) such as alcohol consumption, caffeine use, smoking, and exercise, the causal direction of these relationships is unclear. Purpose The present study used time-series data to examine the temporal dynamics of WHB and sleep characteristics in participants of the SWAN Sleep Study. Methods 303 women completed daily assessments of WHB and wore wrist actigraphs to measure sleep characteristics for the duration of the study (Mean=29.42 days, SD=6.71). Results Vector autoregressive modeling revealed that weekly patterns of sleep and WHB best predicted subsequent sleep and WHB, suggesting that the associations between WHB and sleep persist beyond their immediate influence. Some WHB predicted some subsequent sleep characteristics, but sleep did not predict subsequent WHB. Conclusions These novel findings provide insight into the temporal dynamics of 24-hour behaviors and encourage consideration of both sleep and WHB in health promotion and behavior change efforts. PMID:24043549

  18. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns

    PubMed Central

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  19. Regional Neurodegeneration and Gliosis Are Amplified by Mild Traumatic Brain Injury Repeated at 24-Hour Intervals

    PubMed Central

    Bolton, Amanda Nicholle; Saatman, Kathryn Eileen

    2014-01-01

    Most traumatic brain injuries (TBIs) that occur every year are classified as ‘mild’. Individuals involved in high-risk activities may sustain multiple mild TBIs. We evaluated the acute physiological and histopathological consequences of mild TBI in a mouse model, comparing sham injury, single impact, or 5 impacts at a 24- or 48-hour inter-injury interval. A single closed skull impact resulted in bilateral gliosis in the hippocampus and entorhinal cortex that was proportional to impact depth. Midline impact, at a depth just above the threshold to induce transient unconsciousness, produced occasional axonal injury and degenerating neurons accompanied by astrogliosis in the entorhinal cortex and cerebellum. Mild TBI repeated every 24 hours resulted in bilateral hemorrhagic lesions in the entorhinal cortex along with significantly increased neurodegeneration and microglial activation despite diminished durations of apnea and unconsciousness with subsequent impacts. Astrogliosis and diffusely distributed axonal injury were also observed bilaterally in the cerebellum and the brainstem. When the interval between mild TBIs was increased to 48 hours, the pathological consequences were comparable to a single TBI. Together, these data suggest that in mice the brain remains at increased risk for damage for 24 hours after mild TBI despite reduced acute physiological responses to subsequent mild impacts. PMID:25232942

  20. Physician-pharmacist co-management and 24-hour blood pressure control.

    PubMed

    Chen, Ziqian; Ernst, Michael E; Ardery, Gail; Xu, Yinghui; Carter, Barry L

    2013-05-01

    The objectives of this study were to compare indices of 24-hour blood pressure (BP) following a physician-pharmacist collaborative intervention and to describe the associated changes in antihypertensive medications. This was a secondary analysis of a prospective, cluster-randomized clinical trial conducted in 6 family medicine clinics randomized to co-managed (n=3 clinics, 176 patients) or control (n=3 clinics, 198 patients) groups. Mean ambulatory systolic BP (SBP) was significantly lower in the co-managed vs the control group: daytime BP 122.8 mm Hg vs 134.4 mm Hg (P<.001); nighttime SBP 114.8 mm Hg vs 123.7 mm Hg (P<.001); and 24-hour SBP 120.4 mm Hg vs 131.8 mm Hg (P<.001), respectively. Significantly more drug changes were made in the co-managed than in the control group (2.7 vs 1.1 changes per patient, P<.001), and there was greater diuretic use in co-managed patients (79.6% vs 62.6%, P<.001). Ambulatory BPs were significantly lower for the patients who had a diuretic added during the first month compared with those who never had a diuretic added (P<.01). Physician-pharmacist co-management significantly improved ambulatory BP compared with the control group. Antihypertensive drug therapy was intensified much more for patients in the co-managed group. PMID:23614849

  1. Deviation of innate circadian period from 24 hours reduces longevity in mice

    PubMed Central

    Libert, Sergiy; Bonkowski, Michael S.; Pointer, Kelli; Pletcher, Scott D.; Guarente, Leonard

    2012-01-01

    Summary The variation of individual lifespans, even in highly inbred cohorts of animals and under strictly controlled environmental conditions, is substantial and not well understood. This variation in part could be due to epigenetic variation, which later affects the animal’s physiology and ultimately longevity. Identification of the physiological properties that impact health and lifespan is crucial for longevity research and the development of anti-aging therapies. Here we measured individual circadian and metabolic characteristics in a cohort of inbred F1 hybrid mice and correlated these parameters to their lifespans. We found that mice with innate circadian periods close to 24 hours (revealed during 30 days of housing in total darkness) enjoyed nearly 20% longer lifespans than their littermates, which had shorter or longer innate circadian periods. These findings show that maintenance of a 24 hour intrinsic circadian period is a positive predictor of longevity. Our data suggest that circadian period may be used to predict individual longevity and that processes that control innate circadian period affect aging. PMID:22702406

  2. The Application of a Contact Lens Sensor in Detecting 24-Hour Intraocular Pressure-Related Patterns.

    PubMed

    Xu, Sarah C; Gauthier, Angela C; Liu, Ji

    2016-01-01

    Glaucoma is one of the leading causes of blindness worldwide. Recent studies suggest that intraocular pressure (IOP) fluctuations, peaks, and rhythm are important factors in disease advancement. Yet, current glaucoma management remains hinged on single IOP measurements during clinic hours. To overcome this limitation, 24-hour IOP monitoring devices have been employed and include self-tonometry, permanent IOP, and temporary IOP monitoring. This review discusses each IOP measuring strategy and focuses on the recently FDA-approved contact lens sensor (CLS). The CLS records IOP-related ocular patterns for 24 hours continuously. Using the CLS, IOP-related parameters have been found to be associated with the rate of visual field progression in primary open-angle glaucoma, disease progression in primary angle-closure glaucoma, and various clinical variables in ocular hypertension. The CLS has been used to quantify blink rate and limbal strain and measure the circadian rhythm in a variety of disease states including normal-tension glaucoma and thyroid eye disease. The effects of various IOP-lowering interventions were also characterized using the CLS. CLS provides a unique, safe, and well-tolerated way to study IOP-related patterns in a wide range of disease states. IOP-related patterns may help identify patients most at risk for disease progression and assist with the development of tailored treatments. PMID:27525110

  3. Acute respiratory distress induced by repeated saline lavage provides stable experimental conditions for 24 hours in pigs.

    PubMed

    Muellenbach, Ralf M; Kredel, Markus; Zollhoefer, Bernd; Bernd, Zollhoefer; Johannes, Amelie; Kuestermann, Julian; Schuster, Frank; Schwemmer, Ulrich; Wurmb, Thomas; Wunder, Christian; Roewer, Norbert; Brederlau, Jörg

    2009-04-01

    Surfactant depletion is most often used to study acute respiratory failure in animal models. Because model stability is often criticized, the authors tested the following hypotheses: Repeated pulmonary lavage with normal saline provides stable experimental conditions for 24 hours with a PaO2/FiO2 ratio < 300 mm Hg. Lung injury was induced by bilateral pulmonary lavages in 8 female pigs (51.5 +/- 4.8 kg). The animals were ventilated for 24 hours (PEEP: 5 cm H2O; tidal volume: 6 mL/kg; respiratory rate: 30/min). After 24 hours the animals were euthanized. For histopathology slides from all pulmonary lobes were obtained. Supernatant of the bronchoalveolar fluid collected before induction of acute respiratory distress syndrome (ARDS) and after 24 hours was analyzed. A total of 19 +/- 6 lavages were needed to induce ARDS. PaO2/FiO2 ratio and pulmonary shunt fraction remained significantly deteriorated compared to baseline values after 24 hours (P < .01). Slight to moderate histopathologic changes were detected. Significant increases of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 were observed after 24 hours (P < .01). The presented surfactant depletion-based lung injury model was associated with increased pulmonary inflammation and fulfilled the criteria of acute ling injury (ALI) for 24 hours. PMID:19337905

  4. Tolvaptan Prolongs Blockage of the Vasopressin Type II Receptor Over 24 Hours in Responders With Stage D Heart Failure.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro; Komuro, Issei

    2016-01-01

    The urine aquaporin-2 (U-AQP2) level relative to the plasma arginine vasopressin (P-AVP) level is a novel predictor of the responsiveness to the vasopressin type 2 receptor (V2R) antagonist tolvaptan (TLV). However, little has been reported about the concentration-time profile of U-AQP2 after TLV treatment. We evaluated 24 patients with decompensated stage D heart failure (HF) who had received 3.75 mg/day of TLV on a de novo basis for > 7 days to treat congestion refractory to conventional diuretics. Seventeen patients were TLV-responders, whose 24-hour urine volume (UV) increased after TLV initiation; the other 7 patients were TLV-non-responders. The U-AQP2 of the TLV-responders, corrected for the urine creatinine concentration, decreased significantly at 4 hours after TLV administration without returning to the day-1 morning level on the morning of day-7. The TLV-non-responder U-AQP2 levels remained low even before the TLV treatment. On the morning of day-7, the TLV-responder U-AQP2/P-AVP ratio was comparable to that of the TLV-non-responders. Among 18 patients (11 responders and 7 non-responders), the day-7 TLV trough concentration was 64 ± 62 ng/mL and was negatively correlated with the estimated glomerular filtration rate (eGFR). TLV has antagonistic effects on the V2R over 24 hours in TLV-responders with advanced heart failure and chronic kidney disease, probably due to persistently elevated blood TLV concentration. The unresponsiveness to TLV in the TLV-non-responders is not attributable to malabsorption. PMID:26742881

  5. Association between Sleep Duration and 24-Hour Urine Free Cortisol in the MrOS Sleep Study

    PubMed Central

    Rao, Madhu N.; Blackwell, Terri; Redline, Susan; Punjabi, Naresh M.; Barrett-Connor, Elizabeth; Neylan, Thomas C.; Stone, Katie L.

    2013-01-01

    Context Short sleep duration is associated with adverse health outcomes, but the mechanisms involved are unknown. It has been postulated that short sleep duration may elevate cortisol levels, but studies have had conflicting results. It is unclear whether these differing findings may be due to methodological issues, such as assessment of sleep duration. Specifically, objective versus subjective methods of measuring habitual sleep duration may account for the conflicting results found in epidemiological studies. Objective Our goal was to determine whether habitual sleep duration, measured objectively (by actigraphy) and subjectively (by self-report), was associated with 24-hour urine free cortisol (UFC), a measure of integrated cortisol secretion. Our secondary goal was to determine whether slow wave sleep (SWS, determined by polysomnography) was associated with 24-hour UFC. Design/Setting Cross sectional study of community dwelling older men. Patients/Participants 325 men (mean age = 76.6 years, SD = 5.5) from the Portland site of the MrOS Sleep Study, who underwent 24-hour urine collection, polysomnography, actigraphy and sleep questionnaire. Primary Outcome 24-hour UFC. Results In this study of community dwelling older men, self-reported sleep duration was inversely related to 24-hour UFC levels. Participants reporting <5 hours of habitual sleep had an adjusted mean 24-hour UFC of 29.8 ug, compared to 28.0 ug in participants reporting >5 to <8 hours of sleep 25.5 ug in those reporting >8 hours of habitual sleep. However, sleep duration determined by actigraphy was not associated with 24-hour UFC in either univariable or multivariable regression models. SWS was not associated with 24-hour UFC. Conclusion Objectively measured (i.e., actigraphic) sleep duration is not associated with 24-hour UFC in these community dwelling older men. This finding, together with prior studies, suggests that elevated levels of integrated cortisol secretion is not the

  6. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust launches on time

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Into a pristine blue sky, the Boeing Delta II rocket carrying the Stardust spacecraft leaves clouds of exhaust behind as it lifts off at 4:04:15 p.m. EST from Launch Pad 17-A, Cape Canaveral Air Station. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  7. Time course analysis of gene expression over 24 hours in Fe-deficient barley roots.

    PubMed

    Nagasaka, Seiji; Takahashi, Michiko; Nakanishi-Itai, Reiko; Bashir, Khurram; Nakanishi, Hiromi; Mori, Satoshi; Nishizawa, Naoko K

    2009-03-01

    Typical for a graminaceous plant, barley secretes mugineic acid-family phytosiderophores (MAs) to acquire iron (Fe). Under Fe-deficient conditions, MAs secretion from barley roots increases markedly. Secretion shows a diurnal pattern, with a clear peak 2-3 h after sunrise and cessation within a few hours. Microarray analyses were performed to profile the Fe deficiency-inducible genes in barley roots and diurnal changes in the expression of these genes. Genes encoding enzymes involved in MAs biosynthesis, the methionine cycle, and methionine biosynthesis were highly induced by Fe deficiency. The expression of sulfate transporters was also upregulated by Fe deficiency. Therefore, all of the genes participating in the MAs pathway from sulfur uptake and assimilation to the biosynthesis of MAs were upregulated in Fe-deficient barley roots. In contrast to MAs secretion, the transcript levels of these genes did not show diurnal changes. The amount of endogenous MAs gradually increased during the day after MAs secretion ceased, and was highest before secretion began. These results show that MAs biosynthesis, including the supply of the substrate methionine, occurs throughout the day, and biosynthesized MAs likely accumulate in barley roots until their secretion into the rhizosphere. In contrast, the levels of transcripts encoding an Fe(III)-MAs complex transporter, two putative metal-MAs complex transporters, and HvYS1 were also increased in Fe-deficient barley roots, and the levels of two of these transcripts showed diurnal rhythms. The Fe(III)-MAs complex transporters may absorb Fe(III)-MAs diurnally, synchronous with the diurnal secretion of MAs. PMID:19089316

  8. The Effects of 24-hour Sleep Deprivation on the Exploration-Exploitation Trade-off

    PubMed Central

    Glass, Brian D.; Maddox, W. Todd; Bowen, Christopher; Savarie, Zachary R.; Matthews, Michael D.; Markman, Arthur B.; Schnyer, David M.

    2010-01-01

    Sleep deprivation has a complex set of neurological effects that go beyond a mere slowing of mental processes. While cognitive and perceptual impairments in sleep deprived individuals are widespread, some abilities remain intact. In an effort to characterize these effects, some have suggested an impairment of complex decision making ability despite intact ability to follow simple rules. To examine this trade-off, 24-hour total sleep deprived individuals performed two versions of a resource acquisition foraging task, one in which exploration is optimal (to succeed, abandon low value, high saliency options) and another in which exploitation is optimal (to succeed, refrain from switching between options). Sleep deprived subjects exhibited decreased performance on the exploitation task compared to non-sleep deprived controls, yet both groups exhibited increased performance on the exploratory task. These results speak to previous neuropsychological work on cognitive control. PMID:21686036

  9. After 24-hour scrub, another tower rollback for the Boeing Delta II rocket carrying Stardust

    NASA Technical Reports Server (NTRS)

    1999-01-01

    As tower rollback begins, the Boeing Delta II rocket carrying the Stardust spacecraft waits on Launch Pad 17-A, Cape Canaveral Air Station, for the second launch attempt at 4:04 p.m. EST. The original launch was scrubbed on Feb. 6 for 24 hours. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  10. Tasimelteon: A Review in Non-24-Hour Sleep-Wake Disorder in Totally Blind Individuals.

    PubMed

    Keating, Gillian M

    2016-05-01

    Tasimelteon (Hetlioz(®)) is a dual melatonin receptor agonist indicated for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24) (free-running disorder). In two randomized, double-masked, multicentre, phase III trials, totally blind individuals with Non-24 who received oral tasimelteon 20 mg once nightly were significantly more likely than those receiving placebo to entrain the circadian pacemaker (the SET trial) and maintain entrainment (the RESET trial). Sleep/wake parameters and functioning were also improved with tasimelteon. Oral tasimelteon was generally well tolerated in totally blind patients with Non-24. In conclusion, tasimelteon is a useful drug for the treatment of Non-24 in totally blind individuals. PMID:27003694

  11. Setting Spacecraft Maximum Allowable Concentrations for 1 hour or 24 hour contingency exposures to airborne chemicals

    NASA Technical Reports Server (NTRS)

    Garcia, Hector D.; Limero, Thomas F.; James, John T.

    1992-01-01

    Since the early years of the manned space program, NASA has developed and used exposure limits called Spacecraft Maximum Allowable Concentrations (SMACs) to help protect astronauts from airborne toxicants. Most of these SMACS are based on an exposure duration of 7 days, since this is the duration of a 'typical' mission. A set of 'contingency SMACs' is also being developed for scenarios involving brief (1-hour or 24- hour) exposures to relatively high levels of airborne toxicants from event-related 'contingency' releases of contaminants. The emergency nature of contingency exposures dictates the use of different criteria for setting exposure limits. The NASA JSC Toxicology Group recently began a program to document the rationales used to set new SMACs and plans to review the older, 7-day SMACs. In cooperation with the National Research Council's Committee on Toxicology, a standard procedure has been developed for researching, setting, and documenting SMAC values.

  12. The association of knowledge, attitudes and behaviours related to salt with 24-hour urinary sodium excretion

    PubMed Central

    2014-01-01

    Aim Salt reduction efforts usually have a strong focus on consumer education. Understanding the association between salt consumption levels and knowledge, attitudes and behaviours towards salt should provide insight into the likely effectiveness of education-based programs. Methods A single 24-hour urine sample and a questionnaire describing knowledge, attitudes and behaviours was obtained from 306 randomly selected participants and 113 volunteers from a regional town in Australia. Results Mean age of all participants was 55 years (range 20–88), 55% were women and mean 24-hour urinary salt excretion was 8.8(3.6) g/d. There was no difference in salt excretion between the randomly selected and volunteer sample. Virtually all participants (95%) identified that a diet high in salt can cause serious health problems with the majority of participants (81%) linking a high salt diet to raised blood pressure. There was no difference in salt excretion between those who did 8.7(2.1) g/d and did not 7.5(3.3) g/d identify that a diet high in salt causes high blood pressure (p = 0.1). Nor was there a difference between individuals who believed they consumed “too much” 8.9(3.3) g/d “just the right amount” 8.4(2.6) g/d or “too little salt” 9.1(3.7) g/d (p = 0.2). Likewise, individuals who indicated that lowering their salt intake was important 8.5(2.9) g/d vs. not important 8.8(2.4) g/d did not have different consumption levels (p = 0.4). Conclusion The absence of a clear association between knowledge, attitudes and behaviours towards salt and actual salt consumption suggests that interventions focused on knowledge, attitudes and behaviours alone may be of limited efficacy. PMID:24708561

  13. Fasting for 24 Hours Heightens Reward from Food and Food-Related Cues

    PubMed Central

    Cameron, Jameason D.; Goldfield, Gary S.; Finlayson, Graham; Blundell, John E.; Doucet, Éric

    2014-01-01

    Introduction We examined the impact of a 24 hour complete fast (vs. fed state) on two measures of food reward: 1) ‘wanting’, as measured by response to food images and by the relative-reinforcing value of food (RRV), and 2) ‘liking’, as measured by response to food images and the hedonic evaluation of foods consumed. Methods Utilizing a randomized crossover design, 15 subjects (9 male; 6 female) aged 28.6±4.5 yrs with body mass index 25.3±1.4 kg/m2 were randomized and counterbalanced to normal feeding (FED) and 24-hour fast (FASTED) conditions. Trait characteristics were measured with the Three Factor Eating Questionnaire. Two computer tasks measured food reward: 1) RRV progressive ratio task, 2) explicit ‘liking’ and ‘wanting’ (Leeds Food Preference Questionnaire, LFPQ). Also measured were ad libitum energy intake (EI; buffet) and food ‘liking’ (visual analogue scale) of personalized stimuli. Results There were no significant anthropometric changes between conditions. Appetite scores, hedonic ratings of ‘liking’, and ad libitum EI all significantly increased under the FASTED condition (p<0.05). Under the FASTED condition there were significant increases in the RRV of snack foods; similarly, explicit ‘wanting’ and ‘liking’ significantly increased for all food categories. ‘Liking’ of sweet foods remained high across-meals under FASTED, but savory foods decreased in hedonic saliency. Conclusion Relative to a fed state, we observed an increase in hedonic ratings of food, the rewarding value of food, and food intake after a 24 hr fast. Alliesthesia to food and food cues is suggested by heightened hedonic ratings under the FASTED condition relative to FED. PMID:24454949

  14. A 24-Hour Study of the Hypothalamo-Pituitary Axes in Huntington’s Disease

    PubMed Central

    Nambron, Rajasree; Costelloe, Seán J.; Martin, Nicholas G.; Hill, Nathan R.; Frost, Chris; Watt, Hilary C.; Hindmarsh, Peter; Björkqvist, Maria; Warner, Thomas T.

    2015-01-01

    Background Huntington’s disease is an inherited neurodegenerative disorder characterised by motor, cognitive and psychiatric disturbances. Patients exhibit other symptoms including sleep and mood disturbances, muscle atrophy and weight loss which may be linked to hypothalamic pathology and dysfunction of hypothalamo-pituitary axes. Methods We studied neuroendocrine profiles of corticotropic, somatotropic and gonadotropic hypothalamo-pituitary axes hormones over a 24-hour period in controlled environment in 15 healthy controls, 14 premanifest and 13 stage II/III Huntington’s disease subjects. We also quantified fasting levels of vasopressin, oestradiol, testosterone, dehydroepiandrosterone sulphate, thyroid stimulating hormone, free triiodothyronine, free total thyroxine, prolactin, adrenaline and noradrenaline. Somatotropic axis hormones, growth hormone releasing hormone, insulin-like growth factor-1 and insulin-like factor binding protein-3 were quantified at 06:00 (fasting), 15:00 and 23:00. A battery of clinical tests, including neurological rating and function scales were performed. Results 24-hour concentrations of adrenocorticotropic hormone, cortisol, luteinizing hormone and follicle-stimulating hormone did not differ significantly between the Huntington’s disease group and controls. Daytime growth hormone secretion was similar in control and Huntington’s disease subjects. Stage II/III Huntington’s disease subjects had lower concentration of post-sleep growth hormone pulse and higher insulin-like growth factor-1:growth hormone ratio which did not reach significance. In Huntington’s disease subjects, baseline levels of hypothalamo-pituitary axis hormones measured did not significantly differ from those of healthy controls. Conclusions The relatively small subject group means that the study may not detect subtle perturbations in hormone concentrations. A targeted study of the somatotropic axis in larger cohorts may be warranted. However, the lack

  15. Heart rate variability and arrhythmic patterns of 24-hour Holter electrocardiography among Nigerians with cardiovascular diseases

    PubMed Central

    Adebayo, Rasaaq Ayodele; Ikwu, Amanze Nkemjika; Balogun, Michael Olabode; Akintomide, Anthony Olubunmi; Ajayi, Olufemi Eyitayo; Adeyeye, Victor Oladeji; Mene-Afejuku, Tuoyo Omasan; Bamikole, Olaniyi James; Ogunyemi, Suraj Adefabi; Ajibare, Adeola Olubunmi; Oketona, Omolola Abiodun

    2015-01-01

    Background Facilities for Holter electrocardiography (ECG) monitoring in many Nigerian hospitals are limited. There are few published works in Nigeria on the use of 24-hour Holter ECG in cardiac arrhythmic evaluation of patients with cardiovascular diseases. Objective To study the clinical indications, arrhythmic pattern, and heart rate variability (HRV) among subjects referred for 24-hour Holter ECG at our Cardiac Care Unit. Methods Three-hundred and ten patients (134 males and 176 females) were studied consecutively over a 48-month period using Schiller type (MT-101) Holter ECG machine. Results Out of the 310 patients reviewed, 134 were males (43.2%) and 176 were females (56.8%). The commonest indication for Holter ECG was palpitation followed by syncope in 71 (23%) and 49 (15.8%) of subjects, respectively. Premature ventricular complex and premature atrial complex were the commonest types of arrhythmia in 51.5% and 15% subjects, respectively. Ventricular arrhythmia was more prevalent in dilated cardiomyopathy patients (85.7%). The HRV of subjects with palpitation, stroke, and diabetes mellitus with autonomic neuropathy, using standard deviation of normal to normal intervals average (milliseconds), were 107.32±49.61, 79.15±49.15, and 66.50±15.54, respectively. The HRV, using standard deviation of averages of normal to normal intervals average (milliseconds), of patients with palpitation, stroke, and diabetes mellitus with autonomic neuropathy were 77.39±62.34, 57.82±37.05, and 55.50±12.71, respectively. Conclusion Palpitation and syncope were the commonest indications for Holter ECG among our subjects. The commonest arrhythmic patterns were premature ventricular complex and premature atrial complex, with ventricular arrhythmia being more prevalent in dilated cardiomyopathy. There was a reduction in HRV in patients with stroke and diabetic autonomic neuropathy. PMID:26170685

  16. Effects of exenatide and liraglutide on 24-hour glucose fluctuations in type 2 diabetes.

    PubMed

    Nagakura, Jo; Yamakawa, Tadashi; Taguri, Masataka; Tsuchiya, Hirohisa; Shigematsu, Erina; Suzuki, Jun; Morita, Satoshi; Kadonosono, Kazuaki; Terauchi, Yasuo

    2016-03-31

    We evaluated the influence of short-term treatment with exenatide twice daily or liraglutide once daily on daily blood glucose fluctuations in 40 patients with type 2 diabetes inadequately controlled by sulfonylureas. The patients in a multicenter, open-label trial were randomly assigned to receive add-on exenatide (10 μg/day, n = 21) or add-on liraglutide (0.3-0.9 mg/day, n = 19), and underwent 24-hour continuous subcutaneous glucose monitoring. There was no significant between-group difference in glucose fluctuations during the day, as assessed by calculating mean amplitude of glycemic excursion (MAGE) and standard deviation (SD). However, the mean blood glucose levels at 3 hours after breakfast and dinner were significantly lower in the exenatide group than the liraglutide group (breakfast: 127.3 ± 24.1 vs. 153.4 ± 28.7 mg/dL; p = 0.006, dinner: 108.7 ± 17.3 vs. 141.9 ± 24.2 mg/dL; p < 0.001). In contrast, mean blood glucose levels and their SD were significantly lower between 0000 h and 0600 h in the liraglutide group than the exenatide group (average glucose: 126.9 ± 27.1 vs. 107.1 ± 24.0 mg/dL; p = 0.029, SD: 15.2 ± 10.5 vs. 8.7 ± 3.8; p = 0.020). Both groups had similar glucose fluctuations despite differences in 24-hour blood glucose profiles. Therefore, each of these agents may have advantages or disadvantages and should be selected according to the blood glucose profile of the patient. PMID:26743240

  17. The Canadian 24-Hour Movement Guidelines for Children and Youth: Implications for practitioners, professionals, and organizations.

    PubMed

    Latimer-Cheung, Amy E; Copeland, Jennifer L; Fowles, Jonathon; Zehr, Lori; Duggan, Mary; Tremblay, Mark S

    2016-06-01

    The new Canadian 24-Hour Movement Guidelines for Children and Youth emphasize the integration of all movement behaviours that occur over a whole day (i.e., light, moderate, and vigorous physical activity, sedentary behaviour, and sleep). These guidelines shift the paradigm away from considering each behaviour in isolation. This concept of the "whole day matters" not only calls for a change in thinking about movement but also for redevelopment of dissemination and implementation practice. Past guideline launch activities largely have aimed to create awareness through passive dissemination strategies (e.g., Website posts, distribution of print resources). For the integrated guidelines to have public health impact, we must move beyond dissemination and raising of awareness to implementation and behaviour change. Shifting this focus requires new, innovative approaches to intervention, including interdisciplinary collaboration, policy change, and refocused service provision. The purpose of this paper is to identify practitioners, professionals, and organizations with potential to disseminate and/or implement the guidelines, discuss possible implementation strategies for each of these groups, and describe the few resources being developed and those needed to support dissemination and implementation efforts. This discussion makes readily apparent the need for a well-funded, comprehensive, long-term dissemination, implementation, and evaluation plan to ensure uptake and activation of the guidelines. PMID:27306438

  18. [The diagnostic impact and limitations of 24 hour pH monitoring with multichannel intraluminal impedance].

    PubMed

    Korszun, Karolina; Dyrla, Przemysław; Wojtuń, Stanisław; Gil, Jerzy

    2014-08-01

    Gastroesophageal reflux disease (GERD) is a result of reflux of gastric contents into the esophagus. Gastroscopy is often the first examination performed in GERD diagnosis. Some patients have macroscopic lesions, namely erosions, in the esophagus above the cardia of stomach. It enables to diagnose gastroesophageal reflux disease. However, many patients have no macroscopic lesions of the esophageal mucosa in endoscopy. That is why 24-hour pH monitoring with multichannel intraluminal impedance is the gold standard in diagnosis establishing of GERD and make feasible to distinguish acid, weakly acid and nonacid reflux and its correlation with reported symptoms. Impedance-pH is used to establish diagnosis of GERD, in patient qualification to anti-reflux surgery, to find the cause of not efficient reflux disease treatment as well as the cause of extra-esophageal symptoms of reflux disease. During impedance-pH test catheter connected with the recorder is placed in patient's esophagus. Recorded data is analyzed with the computer program. The examination is safe, the only complication that can occur is nasal bleeding, which can be a result of mucosa damage caused while catheter implementation. Nowadays disposable catheters are used, that excludes the risk of catheter related infection. On the basis of pH-impedance results it is possible to divide patients into 3 groups: patients with functional heartburn, patients with esophageal hypersensitivity and abnormal esophageal acid exposure. This classification is very helpful in the choice of treatment - antireflux surgery, proton pump inhibitor or prokinetic therapy. PMID:25252438

  19. Evaluation study of the California Expanded Food and Nutrition Education Program: 24-hour food recall data.

    PubMed

    Del Tredici, A M; Joy, A B; Omelich, C L; Laughlin, S G

    1988-02-01

    The California Expanded Food and Nutrition Education program (EFNEP) Evaluation Study evaluated the effectiveness of the California program. The eating habits of 683 persons were studied in a group receiving EFNEP instruction (355 participants) and a control group (328 participants) that received no instruction. The 24-hour food recall was used to assess eating habits using the Synectics method. At the beginning of the study, there were no differences in food recall scores between the EFNEP and the control groups. After 6 months of instruction in the EFNEP group, there was a significant increase in food recall score for that group and no change in the control group. The improvements observed in the EFNEP group resulted from increased intakes from the milk, protein, and fruit and vegetable food groups. The program characteristics that led to those changes were determined to be in the length of the EFNEP visit, the number of EFNEP visits, and the EFNEP instruction topics. These results show that the California EFNEP is effective in producing significant changes in the eating habits of the low-income individuals it serves. PMID:3339205

  20. Depressive Symptoms and 24-Hour Ambulatory Blood Pressure in Africans: The SABPA Study

    PubMed Central

    Hamer, Mark; Frasure-Smith, Nancy; Lespérance, François; Harvey, Brian H.; Malan, Nico T.; Malan, Leoné

    2012-01-01

    Disturbances in circadian rhythm might play a central role in the neurobiology of depression. We examined the association between depressive symptoms and 24-hour ambulatory BP in a sample of 405 (197 black and 208 Caucasian) urbanized African teachers aged 25 to 60 yrs (mean 44.6 ± 9.6 yrs). Depressive symptoms were assessed using the self-administered 9-item Patient Health Questionnaire (PHQ-9). After adjusting for age, sex, and ethnicity, participants with severe depressive symptoms (PHQ-9 ≥ 15) had higher odds of hypertension defined from ambulatory BP and/or use of antihypertensive medication (odds ratio = 2.19, 95% CI, 1.00–4.90) in comparison to participants with no symptoms. Compared to Caucasians with no depressive symptoms, those with severe symptoms had blunted nocturnal systolic BP drop of 4.7 mmHg (95% CI, −0.5 to 10.0, P = 0.07). In summary, depressive symptoms were associated with the circadian BP profile in black and Caucasian Africans. PMID:22028954

  1. After 24-hour scrub, the Boeing Delta II rocket carrying Stardust waits for launch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    After a 24-hour postponement, the Boeing Delta II rocket carrying the Stardust spacecraft waits on Launch Pad 17-A, Cape Canaveral Air Station, for its scheduled launch at 4:04 p.m. EST. Umbilical lines (at top) still attached to the fixed utility tower (at right) feed electricity, air conditioning and coolants for the Stardust spacecraft inside the fairing (enclosing the upper stage) before launch. Stardust is destined for a close encounter with the comet Wild 2 in January 2004. Using a silicon-based substance called aerogel, Stardust will capture comet particles flying off the nucleus of the comet. The spacecraft also will bring back samples of interstellar dust. These materials consist of ancient pre-solar interstellar grains and other remnants left over from the formation of the solar system. Scientists expect their analysis to provide important insights into the evolution of the sun and planets and possibly into the origin of life itself. The collected samples will return to Earth in a sample return capsule to be jettisoned as Stardust swings by Earth in January 2006.

  2. Age and individual sleep characteristics affect cognitive performance in anesthesiology residents after a 24-hour shift.

    PubMed

    Tadinac, Meri; Sekulić, Ante; Hromatko, Ivana; Mazul-Sunko, Branka; Ivancić, Romina

    2014-03-01

    Previous research has shown that both shift work and sleep deprivation have an adverse influence on various aspects of human cognitive performance. The aim of this study was to explore changes in cognitive functioning and subjective sleepiness of anesthesiology residents after a 24-hour shift. Twenty-six anesthesiology residents completed a set of psychological instruments at the beginning and at the end of the shift, as well as a questionnaire regarding information about the shift, Stanford Sleepiness Scale, and Circadian Type Questionnaire. There was a significant decline in cognitive performance measured by the Auditory Verbal Learning Test after the shift. The effect was stronger in older participants and in those with high scores on rigidity of sleep scale and low scores on the ability to overcome sleepiness scale. There were no differences in the digits forward test (a measure of concentration), while digits backward test (a measure of working memory) even showed an improved performance after the shift. Although participants reported being significantly sleepier after the shift, the subjective sleepiness did not correlate with any of the objective measures of cognitive performance. In conclusion, the performance in short tasks involving concentration and working memory was not impaired, while performance in long-term and monotone tasks declined after sleep deprivation, and the magnitude of this decline depended on the specific individual characteristics of sleep and on age Surprisingly, age seemed to have an important impact on cognitive functions after shift work even in the relatively age-homogeneous population of young anesthesiology residents. PMID:24974663

  3. Accuracy of commercial 24-hour electrocardiogram analyzers for quantitation of total and repetitive ventricular arrhythmias.

    PubMed

    Salerno, D M; Granrud, G; Hodges, M

    1987-12-01

    The accuracy of 2 commercial 24-hour electrocardiogram analyzers was tested for quantitation of ventricular premature complexes (VPCs). Scanner 1 was the Cardiodata Systems Mark III and scanner 2 was the Avionics Trendsetter DCG VII. Twenty-four-hour electrocardiographic recordings from 19 consecutive ambulatory patients with frequent VPCs were analyzed by each device. Results were compared with those from hand counts of complete printouts of each of the 19 recordings. For total VPCs, scanner 1 had an average error of 13% (range 0 to 58%) and scanner 2 had an average error of 24% (range (1 to 80%). Scanner 1 had an error of more than 10% for 9 of the 19 recordings and scanner 2 more than 10% for 11 of the 19 recordings. For paired VPCs, scanner 1 had a mean error of 23% (range 4 to 77%), and scanner 2 of 56% (range 34 to 79%). For nonsustained ventricular tachycardia, scanner 1 had an average error of 20% (range 8 to 41%) and scanner 2 had an error of 56% (range 34 to 78%). Thus, when recordings from consecutive ambulatory patients with frequent VPCs were analyzed, neither device was consistently accurate for quantitation of total VPCs. Both analyzers had an unacceptable error for quantitation of repetitive VPCs. All currently available devices may have comparably large errors. This possibility is confirmed by recalculation of the reported data from a third scanner. PMID:2446488

  4. Deep venous thrombophlebitis: detection with 4-hour versus 24-hour platelet scintigraphy

    SciTech Connect

    Seabold, J.E.; Conrad, G.R.; Ponto, J.A.; Kimball, D.A.; Frey, E.E.; Ahmed, F.; Coughlan, J.D.; Jensen, K.C.

    1987-11-01

    Thirty-one nonheparinized patients with suspected deep venous thrombophlebitis (DVT) underwent contrast venography and indium-111 platelet scintigraphy (In-111 PS). Venography permitted identification of acute DVT in 12 of 31 cases (39%). One additional patient was considered to have acute DVT despite nonconclusive venography results. In-111 PS results were positive at 4 hours in nine of 13 cases (69%) and at 24 hours in 12 of 13 cases (92%). Two of four patients with false-negative 4-hour In-111 PS studies had received warfarin. Thus, the sensitivity of 4-hour In-111 PS in patients not receiving anticoagulants was 82%. Venography results were negative for acute DVT in 18 cases, and 4-hour In-111 PS studies were negative or equivocal in each. In-111 PS is an alternative to contrast venography for detecting acute DVT. If 4-hour In-111 PS results are positive, anticoagulation can be initiated. Delayed images are necessary if the 4-hour images are negative or equivocal.

  5. The 24-hour pulse wave velocity, aortic augmentation index, and central blood pressure in normotensive volunteers

    PubMed Central

    Kuznetsova, Tatyana Y; Korneva, Viktoria A; Bryantseva, Evgeniya N; Barkan, Vitaliy S; Orlov, Artemy V; Posokhov, Igor N; Rogoza, Anatoly N

    2014-01-01

    The purpose of this study was to examine the pulse wave velocity, aortic augmentation index corrected for heart rate 75 (AIx@75), and central systolic and diastolic blood pressure during 24-hour monitoring in normotensive volunteers. Overall, 467 subjects (206 men and 261 women) were recruited in this study. Participants were excluded from the study if they were less than 19 years of age, had blood test abnormalities, had a body mass index greater than 2 7.5 kg/m2, had impaired glucose tolerance, or had hypotension or hypertension. Ambulatory blood pressure monitoring (ABPM) with the BPLab® device was performed in each subject. ABPM waveforms were analyzed using the special automatic Vasotens® algorithm, which allows the calculation of pulse wave velocity, AIx@75, central systolic and diastolic blood pressure for “24-hour”, “awake”, and “asleep” periods. Circadian rhythms and sex differences in these indexes were identified. Pending further validation in prospective outcome-based studies, our data may be used as preliminary diagnostic values for the BPLab ABPM additional index in adult subjects. PMID:24812515

  6. Mean 24-hours sympathetic nervous system activity decreases during head-down tilted bed rest but not during microgravity

    NASA Astrophysics Data System (ADS)

    Christensen, Nj; Heer, M.; Ivanova, K.; Norsk, P.

    Sympathetic nervous system activity is closely related to gravitational stress in ground based experiments. Thus a high activity is present in the standing-up position and a very low activity is observed during acute head-out water immersion. Adjustments in sympathetic activity are necessary to maintain a constant blood pressure during variations in venous return. Head-down tilted bed rest is applied as a model to simulate changes observed during microgravity. The aim of the present study was to test the hypothesis that mean 24-hours sympathetic activity was low and similar during space flight and in ground based observation obtained during long-term head-down tilted bed rest. Forearm venous plasma noradrenaline was measured by a radioenzymatic technique as an index of muscle sympathetic activity and thrombocyte noradrenaline and adrenaline were measured as indices of mean 24-hours sympathoadrenal activity. Previous results have indicated that thrombocyte noradrenaline level has a half-time of 2 days. Thus to reflect sympathetic activity during a specific experiment the study period must last for at least 6 days and a sample must be obtained within 12 hours after the experiment has ended. Ten normal healthy subjects were studied before and during a 14 days head-down tilted bed rest as well as during an ambulatory study period of a similar length. The whole experiment was repeated while the subjects were on a low calorie diet. Thrombocyte noradrenaline levels were studied in 4 cosmonauts before and within 12 hours after landing after more than 7 days in flight. Thrombocyte noradrenaline decreased markedly during the head-down tilted bed rest (p<0.001), whereas there were no significant changes in the ambulatory study. Plasma noradrenaline decreased in the adaptation period but not during the intervention. During microgravity thrombocyte noradrenaline increased in four cosmonauts and the percentage changes were significantly different in cosmonauts and in subjects

  7. A 24-HOUR AMBULATORY ECG MONITORING IN ASSESSMENT OF QT INTERVAL DURATION AND DISPERSION IN ROWERS WITH PHYSIOLOGICAL MYOCARDIAL HYPERTROPHY

    PubMed Central

    Kim, Z.F.; Bilalova, R.R.; Tsibulkin, N.A.; Almetova, R.R.; Mudarisova, R.R.; Ahmetov, I.I.

    2013-01-01

    Myocardial hypertrophy (MH) due to cardiac pathology is characterized by an increase in QT interval duration and dispersion, while the findings for exercise-induced myocardial hypertrophy are contradictory. The majority of published research findings have not explored this relationship, but there have only been a few conducted studies using 24-hour ECG monitoring. The aim of the study was to determine the QT interval duration and dispersion in short-term and 24-hour ECG in endurance athletes with myocardial hypertrophy and without it. Methods: A total of 26 well-trained rowers underwent a resting 12-lead ECG, 24-hour ECG monitoring and echocardiography. Results: Athletes with MH (n = 7) at rest did not show any increase in QTc interval duration and dispersion, or mean and maximal QTc duration in Holter monitoring compared to athletes without MH (n = 19). Left ventricular mass was not significantly correlated with any QTc characteristics. Furthermore, athletes with MH had significantly longer mean QT (P = 0.01) and maximal QT (P = 0.018) intervals in Holter monitoring and higher 24-hour heart rate variability indexes due to stronger vagal effects. Conclusions: The present study demonstrated that athlete's heart syndrome with myocardial hypertrophy as a benign phenomenon does not lead to an increase in QT interval duration, or increases in maximal and mean duration in a 24-hour ECG. An increase in QT interval duration in athletes may have an autonomic nature. PMID:24744494

  8. Difference in 24-Hour Urine Composition between Diabetic and Non-Diabetic Adults without Nephrolithiasis

    PubMed Central

    Qin, Jing; Duan, Xiaolu; Liu, Yang; Zhao, Zhijian; Yuan, Jian; Wan, Shaw P.; Zeng, Guohua

    2016-01-01

    Background Diabetic patients are more likely to develop kidney stones than the general population. The underlying mechanisms for this disparity remain to be elucidated. Little is known about the relationship between urine composition and diabetes mellitus in non-stone-forming individuals. We sought to examine the differences in the 24-hour (24-h) urine composition between diabetic and non-diabetic adults who were not stone formers. Methods A convenience sample of 538 individuals without a history of nephrolithiasis, gout, hyperparathyroidism, or gastroenteric diseases participated in this study. The 24-h urine profiles of 115 diabetic adults were compared with those of 423 non-diabetic adults. Diabetes was defined by self-reported physician diagnosis or medication use. All participants were non-stone formers confirmed by urinary tract ultrasonography. Participants provided a fasting blood sample and a single 24-h urine collection for stone risk analysis. Student’s t-test was used to compare mean urinary values. Linear regression models were adjusted for age, gender, body mass index, hypertension, fasting serum glucose, serum total cholesterol, estimated creatinine clearance rate and urinary factors. Results Univariable analysis showed that the diabetic participants had significantly higher 24-h urine volumes and lower urine calcium and magnesium excretions than non-diabetic participants (all P < 0.05). After multivariate adjustment, no significant differences in 24-h urine composition were observed between diabetic and non-diabetic participants except for a slightly increased 24-h urine volume in diabetic participants (all P > 0.05). The main limitation of this study is that the convenience samples and self-reported data may have been sources of bias. Conclusion Our data showed that there were no differences in 24-h urine composition between diabetic and non-diabetic adults who are not stone formers. The reason for it might be the improved glycemic control in

  9. An Analysis of 24-Hour Ambulatory Blood Pressure Monitoring Data using Orthonormal Polynomials in the Linear Mixed Model

    PubMed Central

    Edwards, Lloyd J.; Simpson, Sean L.

    2014-01-01

    Background The use of 24-hour ambulatory blood pressure monitoring (ABPM) in clinical practice and observational epidemiological studies has grown considerably in the past 25 years. ABPM is a very effective technique for assessing biological, environmental, and drug effects on blood pressure. Objectives In order to enhance the effectiveness of ABPM for clinical and observational research studies via analytical and graphical results, developing alternative data analysis approaches using modern statistical techniques are important. Methods The linear mixed model for the analysis of longitudinal data is particularly well-suited for the estimation of, inference about, and interpretation of both population (mean) and subject-specific trajectories for ABPM data. We propose using a linear mixed model with orthonormal polynomials across time in both the fixed and random effects to analyze ABPM data. Results We demonstrate the proposed analysis technique using data from the Dietary Approaches to Stop Hypertension (DASH) study, a multicenter, randomized, parallel arm feeding study that tested the effects of dietary patterns on blood pressure. Conclusions The linear mixed model is relatively easy to implement (given the complexity of the technique) using available software, allows for straight-forward testing of multiple hypotheses, and the results can be presented to research clinicians using both graphical and tabular displays. Using orthonormal polynomials provides the ability to model the nonlinear trajectories of each subject with the same complexity as the mean model (fixed effects). PMID:24667908

  10. Tasimelteon (Hetlioz™): A New Melatonin Receptor Agonist for the Treatment of Non-24-Hour Sleep-Wake Disorder.

    PubMed

    Bonacci, Janene M; Venci, Jineane V; Gandhi, Mona A

    2015-10-01

    In January 2014, the US Food and Drug Administration approved tasimelteon (Hetlioz™), a melatonin-receptor agonist for the treatment of non-24-hour sleep-wake disorder. This article provides an overview of the mechanism of action, pharmacokinetic properties, as well as the clinical efficacy, safety, and tolerability of tasimelteon. Relevant information was identified through a comprehensive literature search of several databases using the key words tasimelteon, Non-24-hour Sleep-Wake disorder, Non-24, and melatonin. Further information was obtained from the tasimelteon package insert, fda.gov, clinicaltrials.gov, briefing materials provided by Vanda Pharmaceuticals, and posters from scientific meetings. PMID:25092604

  11. 24-hour central aortic systolic pressure and 24-hour central pulse pressure are related to diabetic complications in type 1 diabetes – a cross-sectional study

    PubMed Central

    2013-01-01

    Background Non-invasive measurements of 24 hour ambulatory central aortic systolic pressure (24 h-CASP) and central pulse pressure (24 h-CPP) are now feasible. We evaluate the relationship between 24 h central blood pressure and diabetes-related complications in patients with type 1 diabetes. Methods The study was cross-sectional, including 715 subjects: 86 controls (C), 69 patients with short diabetes duration (< 10 years), normoalbuminuria (< 30 mg/24 h) without receiving antihypertensive treatment (SN), 211 with longstanding diabetes (≥ 10 years) and normoalbuminuria (LN), 163 with microalbuminuria (30-299 mg/24 h) (Mi) and 186 with macroalbuminuria (> 300 mg/24 h) (Ma). 24 h-CASP and 24 h-CPP was measured using a tonometric wrist-watch-like device (BPro, HealthStats, Singapore) and derived using N-point moving average. Results In C, SN, LN, Mi and Ma mean ± SD 24 h-CASP was: 114 ± 17, 115 ± 13, 121 ± 13, 119 ± 16 and 121 ± 13 mmHg (p < 0.001); and 24 h-CPP: 38 ± 8, 38 ± 7, 44 ± 10, 46 ± 11 and 46 ± 11 mmHg, (p < 0.001). Following rigorous adjustment (24 h mean arterial pressure and conventional risk factors), 24 h-CASP and 24 h-CPP increased with diabetes, albuminuria degree, previous cardiovascular disease (CVD), retinopathy and autonomic dysfunction (p ≤ 0.031). Odds ratios per 1 standard deviation increase in 24 h-CASP, 24 h-CPP and 24 h systolic blood pressure (24 h-SBP) were for CVD: 3.19 (1.68-6.05), 1.43 (1.01-2.02) and 2.39 (1.32-4.33), retinopathy: 4.41 (2.03-9.57), 1.77 (1.17-2.68) and 3.72 (1.85-7.47) and autonomic dysfunction: 3.25 (1.65-6.41), 1.64 (1.12-2.39) and 2.89 (1.54-5.42). Conclusions 24 h-CASP and 24 h-CPP was higher in patients vs. controls and increased with diabetic complications independently of covariates. Furthermore, 24 h-CASP was stronger associated to complications than 24 h-SBP. The prognostic significance of 24 h-CASP and 24 h-CPP needs to be determined in follow-up studies. Trial

  12. Self-Renewal and Differentiation Capacity of Urine-Derived Stem Cells after Urine Preservation for 24 Hours

    PubMed Central

    Shi, Yingai; Bharadwaj, Shantaram; Leng, Xiaoyan; Zhou, Xiaobo; Liu, Hong; Atala, Anthony; Zhang, Yuanyuan

    2013-01-01

    Despite successful approaches to preserve organs, tissues, and isolated cells, the maintenance of stem cell viability and function in body fluids during storage for cell distribution and transportation remains unexplored. The aim of this study was to characterize urine-derived stem cells (USCs) after optimal preservation of urine specimens for up to 24 hours. A total of 415 urine specimens were collected from 12 healthy men (age range 20–54 years old). About 6×104 cells shed off from the urinary tract system in 24 hours. At least 100 USC clones were obtained from the stored urine specimens after 24 hours and maintained similar biological features to fresh USCs. The stored USCs had a “rice grain” shape in primary culture, and expressed mesenchymal stem cell surface markers, high telomerase activity, and normal karyotypes. Importantly, the preserved cells retained bipotent differentiation capacity. Differentiated USCs expressed myogenic specific proteins and contractile function when exposed to myogenic differentiation medium, and they expressed urothelial cell-specific markers and barrier function when exposed to urothelial differentiation medium. These data demonstrated that up to 75% of fresh USCs can be safely persevered in urine for 24 hours and that these cells stored in urine retain their original stem cell properties, indicating that preserved USCs could be available for potential use in cell-based therapy or clinical diagnosis. PMID:23349776

  13. The association of resting state heart rate variability and 24-hour blood pressure variability in spinal cord injury.

    PubMed

    Thayer, Julian F; Sollers, John J; Clamor, Annika; Koenig, Julian; Hagglund, Kristofer J

    2016-02-15

    Patients with high cervical complete spinal cord injuries (tetraplegia) sustain damage to the autonomic neural pathways that influence cardiovascular functioning and produce variability in the heart rate (HR) and blood pressure (BP). In non-injured individuals, an inverse relationship exists between resting autonomic control of the heart (as evidenced by HR variability (HRV)) and BP variability (BPV). This study examined the relationship between HRV, BP and BPV in individuals with tetraplegic (n=10) and paraplegic (n=10) spinal cord injuries, and a group of healthy controls (n=14). Resting HRV at baseline and 24-hour ambulatory BP measurements were collected from electrocardiogram measures of each participant. HRV was quantified using time- and frequency-domain measures. The standard deviation of the BP measurements was used as an index of BPV. Multivariate analyses of variance were performed to examine group differences for laboratory-based and 24-h dependent variables. The MANOVAs for HRV parameters (λ(14,50)=.352, p=.010, η(2)=.407) and for BP indices and HR (λ(16,48)=.318, p=.013, η(2)=.436) were significant. Furthermore, in line with existing evidence, we found that vagally mediated HRV was inversely related to BPV in healthy controls. However, this relationship did not hold for the tetraplegia group (ρ<|.42|), and mixed results were found for the paraplegia group (e.g., ρ<|.29| for time domain HRV, ρ>|.65| for low-frequency power). These results support the conclusion that the damage to the spinal sympathetic pathways to the heart found in people with tetraplegia causes a significant disruption in baroreflex control of BP. PMID:26810517

  14. Microleakage of Two Self-Adhesive Cements in the Enamel and Dentin After 24 Hours and Two Months

    PubMed Central

    Jaberi Ansari, Zahra; Kalantar Motamedi, Mojdeh

    2014-01-01

    Objective: Microleakage is a main cause of restorative treatment failure. In this study, we compared occlusal and cervical microleakage of two self-adhesive cements after 24 hours and two months. Materials and Methods: In this in-vitro experimental study, class II inlay cavities were prepared on 60 sound human third molars. Composite inlays were fabricated with Z100 composite resin. The teeth were randomly assigned to six groups. RelyX-Arc (control), RelyX-Unicem and Maxcem were used for the first three groups and specimens were stored in distilled water at 37°C for 24 hours. The same cements were used for the remaining three groups, but the specimens were stored for 2 months. The teeth were subjected to 500 thermal cycles (5°C and 55°C) and immersed in 0.5% basic fuchsin for 24 hours and then sectioned mesiodistally and dye penetration was evaluated in a class II cavity with occlusal and cervical margins using X20 magnification stereomicroscope. Data were analyzed using Kruskal Wallis and Mann-Whitney U tests. Results: After 24 hours, cements had significant differences only in cervical margin microleakage (P=0.0001) and microleakage of RelyX-Unicem and Maxcem was significantly more than that of RelyX-Arc (both P=0.0001). Cervical microleakage in RelyX-Unicem and Maxcem was greater than occlusal (P=0.0001 and P=0.001, respectively). Microleakage was not significantly different between the occlusal and cervical margins after 2 months. Conclusion: Cervical microleakage was greater than occlusal in RelyX-Unicem and Maxcem after 24h. The greatest microleakage was reported for the cervical margin of RelyX-Unicem after 24 hours. PMID:25584053

  15. Irregular 24-hour Activity Rhythms and the Metabolic Syndrome in Older Adults

    PubMed Central

    Sohail, Shahmir; Yu, Lei; Bennett, David A.; Buchman, Aron S.; Lim, Andrew S.P.

    2015-01-01

    Circadian rhythms – near 24-hour intrinsic biological rhythms – modulate many aspects of human physiology and hence disruption of circadian rhythms may have an important impact on human health. Experimental work supports a potential link between irregular circadian rhythms and several key risk factors for cardiovascular disease including hypertension, obesity, diabetes, and dyslipidemia, collectively termed the metabolic syndrome. While several epidemiological studies have demonstrated an association between shift-work and the components of the metabolic syndrome in working-age adults, there is a relative paucity of data concerning the impact of non-occupational circadian irregularity in older women and men. To address this question, we studied 7 days of actigraphic data from 1137 older woman and men participating in the Rush Memory and Aging Project, a community-based cohort study of the chronic conditions of aging. The regularity of activity rhythms was quantified using the nonparametric interdaily stability metric, and was related to the metabolic syndrome and its components obesity, hypertension, diabetes, and dyslipidemia. More regular activity rhythms were associated with a lower odds of having the metabolic syndrome (OR=0.69, 95%CI=0.60–0.80, p=5.8×10−7), being obese (OR=0.73, 95%CI=0.63–0.85, p=2.5×10−5), diabetic (OR=0.76, 95%CI=0.65–0.90, p=9.3×10−4), hypertensive (OR=0.78, 95%CI=0.66–0.91, p=2.0×10−3), or dyslipidemic (OR=0.82, 95%CI=0.72–0.92, p=1.2×10−3). These associations were independent of differences in objectively measured total daily physical activity or rest, and were not accounted for by prevalent coronary artery disease, stroke, or peripheral artery disease. Moreover, more regular activity rhythms were associated with lower odds of having cardiovascular disease (OR=0.83; 95%CI=0.73–0.95, p=5.7×10−3), an effect that was statistically mediated by the metabolic syndrome. We conclude that irregular activity

  16. Decreased striatal dopamine release underlies increased expression of long-term synaptic potentiation at corticostriatal synapses 24 hours after 3-nitropropionic acid induced chemical hypoxia

    PubMed Central

    Akopian, Garnik; Crawford, Cynthia; Beal, M. Flint; Cappelletti, Maurand; Jakowec, Michael W.; Petzinger, Giselle M.; Zheng, Ling; Gheorghe, Stacey L.; Reichel, Carmela M.; Chow, Robert; Walsh, John P

    2008-01-01

    The striatum is particularly sensitive to the irreversible inhibitor of succinate dehyrdrogenase 3-nitropropionic acid (3-NP). In the present study we examined early changes in behavior and dopamine and glutamate synaptic physiology created by a single systemic injection of 3-NP in Fischer 344 rats. Hind limb dystonia was seen 2 hours after 3-NP injections and rats performed poorly on balance beam and rota-rod motor tests 24 hours later. Systemic 3-NP increased NMDA receptor-dependent long-term potentiation (LTP) at corticostriatal synapses over the same time period. The 3-NP induced corticostriatal LTP was not due to increased NMDA receptor number or function, since 3-NP did not change MK-801 binding or NMDA/AMPA receptor current ratios. The LTP seen 24 hours after 3-NP was D1 receptor-dependent and reversed by exogenous addition of dopamine or a D2 receptor agonist to brain slices. High performance liquid chromatography and fast scan cyclic voltammetry revealed a decrease in dopamine content and release in rats injected 24 hours earlier with 3-NP, and much like the enhanced LTP, dopamine changes were reversed by 48 hours. Tyrosine hydroxylase expression was not changed and there was no evidence of striatal cell loss at 24–48 hours after 3-NP exposure. Sprague-Dawley rats showed similar physiological responses to systemic 3-NP, albeit with reduced sensitivity. Thus, 3-NP causes significant changes in motor behavior marked by parallel changes in striatal dopamine release and corticostriatal synaptic plasticity. PMID:18799690

  17. Changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers

    PubMed Central

    2014-01-01

    Background The effects of running and cycling on changes in hydration status and body composition during a 24-hour race have been described previously, but data for 24-hour ultra-mountain bikers are missing. The present study investigated changes in foot volume, body composition, and hydration status in male and female 24-hour ultra-mountain bikers. Methods We compared in 49 (37 men and 12 women) 24-hour ultra-mountain bikers (ultra-MTBers) changes (Δ) in body mass (BM). Fat mass (FM), percent body fat (%BF) and skeletal muscle mass (SM) were estimated using anthropometric methods. Changes in total body water (TBW), extracellular fluid (ECF) and intracellular fluid (ICF) were determined using bioelectrical impedance and changes in foot volume using plethysmography. Haematocrit, plasma [Na+], plasma urea, plasma osmolality, urine urea, urine specific gravity and urine osmolality were measured in a subgroup of 25 ultra-MTBers (16 men and 9 women). Results In male 24-hour ultra-MTBers, BM (P < 0.001), FM (P < 0.001), %BF (P < 0.001) and ECF (P < 0.05) decreased whereas SM and TBW did not change (P > 0.05). A significant correlation was found between post-race BM and post-race FM (r = 0.63, P < 0.001). In female ultra-MTBers, BM (P < 0.05), %BF (P < 0.05) and FM (P < 0.001) decreased, whereas SM, ECF and TBW remained stable (P > 0.05). Absolute ranking in the race was related to Δ%BM (P < 0.001) and Δ%FM in men (P < 0.001) and to Δ%BM (P < 0.05) in women. In male ultra-MTBers, increased post-race plasma urea (P < 0.001) was negatively related to absolute ranking in the race, Δ%BM, post-race FM and Δ%ECF (P < 0.05). Foot volume remained stable in both sexes (P > 0.05). Conclusions Male and female 24-hour ultra-MTBers experienced a significant loss in BM and FM, whereas SM remained stable. Body weight changes and increases in plasma urea do not reflect a change in body hydration status. No oedema

  18. Food Intake Recording Software System, version 4 (FIRSSt4): A Self-Completed 24 Hour Dietary Recall for Children

    PubMed Central

    Baranowski, Tom; Islam, Noemi; Douglass, Deirdre; Dadabhoy, Hafza; Beltran, Alicia; Baranowski, Janice; Thompson, Debbe; Cullen, Karen W.; Subar, Amy F.

    2012-01-01

    The Food Intake Recording Software System, version 4(FIRSSt4), is a web-based 24 hour dietary recall (24hdr) self-administered by children based on the Automated Self-Administered 24-hour recall (ASA24) (a self-administered 24hdr for adults). The food choices in FIRSST4 are abbreviated to include only those reported by children in U.S. national surveys; and detailed food probe questions are simplified to exclude those that children could not be expected to answer (for example questions regarding food preparation and added fats). ASA24 and FIRSSt4 incorporate 10,000+ food images with up to eight images per food to assist in portion size estimation. This paper reviews the formative research conducted during the development of FIRSSt4. When completed, FIRSSt4 will be hosted and maintained for investigator use on the National Cancer Institute’s ASA24 website. PMID:22616645

  19. Dipstick Spot urine pH does not accurately represent 24 hour urine PH measured by an electrode

    PubMed Central

    Omar, Mohamed; Sarkissian, Carl; Jianbo, Li; Calle, Juan; Monga, Manoj

    2016-01-01

    ABSTRACT Objectives To determine whether spot urine pH measured by dipstick is an accurate representation of 24 hours urine pH measured by an electrode. Materials and Methods We retrospectively reviewed urine pH results of patients who presented to the urology stone clinic. For each patient we recorded the most recent pH result measured by dipstick from a spot urine sample that preceded the result of a 24-hour urine pH measured by the use of a pH electrode. Patients were excluded if there was a change in medications or dietary recommendations or if the two samples were more than 4 months apart. A difference of more than 0.5 pH was considered an inaccurate result. Results A total 600 patients were retrospectively reviewed for the pH results. The mean difference in pH between spot urine value and the 24 hours collection values was 0.52±0.45 pH. Higher pH was associated with lower accuracy (p<0.001). The accuracy of spot urine samples to predict 24-hour pH values of <5.5 was 68.9%, 68.2% for 5.5 to 6.5 and 35% for >6.5. Samples taken more than 75 days apart had only 49% the accuracy of more recent samples (p<0.002). The overall accuracy is lower than 80% (p<0.001). Influence of diurnal variation was not significant (p=0.588). Conclusions Spot urine pH by dipstick is not an accurate method for evaluation of the patients with urolithiasis. Patients with alkaline urine are more prone to error with reliance on spot urine pH. PMID:27286119

  20. Reliability and Predictive Validity of Caloric Intake Measures from the 24-Hour Dietary Recalls of Homebound Older Adults

    PubMed Central

    Sun, Yanhui; Roth, David L.; Ritchie, Christine S.; Burgio, Kathryn L.; Locher, Julie L.

    2010-01-01

    24-hour dietary recalls are used frequently to study homebound older adults’ eating behaviors. However, the reliability and predictive validity of this method have not been established in this population. The purpose of this study is to examine whether homebound older adults provide reliable and valid measures of total caloric intake in 24-hour dietary recalls. 230 homebound older adults were interviewed in their homes using a questionnaire to assess eating behaviors and factors that could affect those behaviors. Participants completed three 24-hour dietary recalls at baseline and again at 6-month follow-up. Two sub-samples were identified for analyses. For participants who were not hospitalized during the 6-month interval and had their weight measured at both assessments (n = 52), sufficient test-retest reliability of caloric intake was observed (r = 0.59); but caloric intake deficiencies relative to estimated energy requirements did not predict actual weight loss (r = 0.08). When this sample was supplemented with 91 participants who experienced any adverse event (weight loss of 2.5% or more, hospitalization, institutionalization, or mortality) in the 6-month period (n = 143), adverse events were more likely to occur for those with insufficient caloric intake (odds ratio = 3.49, p = .009), and in White participants compared to African American participants (odds ratio = 3.13, p=0.016). Adequate test-retest reliability of the 24-hour dietary recall was demonstrated, but additional research with larger samples and longer follow-up intervals are needed to better evaluate the predictive validity of caloric intake measures for this population. PMID:20430140

  1. HOW RELIABLE IS 24 HOUR SERUM LITHIUM LEVEL AFTER A TEST DOSE OF LITHIUM IN PREDICTING OPTIMAL LITHIUM DOSE?

    PubMed Central

    Kuruvilla, K.; Shaji, K.S.

    1989-01-01

    SUMMARY 57% of a group of 35 patients treated with Lithium Carbonate at dosages predicted by the nomogram suggested by Cooper et al (1973) failed to reach therapeutic levels of serum lithium. This finding casts serious doubts on the usefulness of the claim by Cooper et al (1973 & 1976) that 24 hour serum lithium level after a test dose of 600 mg. lithium can predict the daily lithium dose. PMID:21927360

  2. Perfusion-CT - Can We Predict Acute Pancreatitis Outcome within the First 24 Hours from the Onset of Symptoms?

    PubMed Central

    Pieńkowska, Joanna; Gwoździewicz, Katarzyna; Skrobisz-Balandowska, Katarzyna; Marek, Iwona; Kostro, Justyna; Szurowska, Edyta; Studniarek, Michał

    2016-01-01

    Purpose Severe acute pancreatitis (AP) is still a significant clinical problem which is associated with a highly mortality. The aim of this study was the evaluation of prognostic value of CT regional perfusion measurement performed on the first day of onset of symptoms of AP, in assessing the risk of developing severe form of acute pancreatitis. Material and Methods 79 patients with clinical symptoms and biochemical criteria indicative of acute pancreatitis (acute upper abdominal pain, elevated levels of serum amylase and lipase) underwent perfusion CT within 24 hours after onset of symptoms. The follow-up examinations were performed after 4–6 days to detect progression of the disease. Perfusion parameters were compared in 41 people who developed severe form of AP (pancreatic and/or peripancreatic tissue necrosis) with parameters in 38 consecutive patients in whom course of AP was mild. Blood flow, blood volume, mean transit time and permeability surface area product were calculated in the three anatomic pancreatic subdivisions (head, body and tail). At the same time the patient's clinical status was assessed by APACHE II score and laboratory parameters such as CRP, serum lipase and amylase, AST, ALT, GGT, ALP and bilirubin were compared. Results Statistical differences in the perfusion parameters between the group of patients with mild and severe AP were shown. Blood flow, blood volume and mean transit time were significantly lower and permeability surface area product was significantly higher in patients who develop severe acute pancreatitis and presence of pancreatic and/or peripancreatic necrosis due to pancreatic ischemia. There were no statistically significant differences between the two groups in terms of evaluated on admission severity of pancreatitis assessed using APACHE II score and laboratory tests. Conclusions CT perfusion is a very useful indicator for prediction and selection patients in early stages of acute pancreatitis who are at risk of

  3. [Exercise tolerance in angina patients 3 and 24 hours after administration of a new delayed-action preparation of metoprolol].

    PubMed

    Giusti, C; Verdecchia, P; Pentimone, F; Regoli, F; Cordoni, M; Bongini, A M

    1981-01-01

    To assess the duration of improved exercise tolerance by metoprolol given in a new sustained-release formulation, 40 in-patients affected by stable exercise-induced angina pectoris received single-blind placebo in day 1 and thereafter, in double-blind cross-over once daily administration, metoprolol RETARD 100 mg and 200 mg in days 3 and 5. Symptom-limited cycloergometric exercise tests were performed at 3 and 24 hours after placebo and after each of the two doses of metoprolol RETARD. Duration of exercise, maximal workload and total work performed did significantly increase at 3 and 24 hours after metoprolol RETARD 100 mg (P less than 0.01) and 200 mg (P less than 0.01), without any significant difference between the two doses. Peak systolic arterial pressure and heart rate were lowered by metoprolol RETARD 200 mg at 3 (P less than 0.01) and 24 (P less than 0.01) hours, whereas only the peak heart rate at 3 hours was lowered (P less than 0.05) by the 100 mg dose. It is concluded that in patients with stable exercise-induced angina pectoris, metoprolol RETARD 200 mg appears to be able to increase exercise tolerance and to reduce exercise-induced myocardial oxygen consumption throughout 24 hours period. This may justify a once daily dosing schedule of the 200 mg dose, aimed at improving patient compliance. PMID:7343379

  4. Assessment of 24-hours Aldosterone Administration on Protein Abundances in Fluorescence-Sorted Mouse Distal Renal Tubules by Mass Spectrometry

    PubMed Central

    Jensen, Thomas B; Pisitkun, Trairak; Hoffert, Jason D; Jensen, Uffe B; Fenton, Robert A; Praetorius, Helle A; Knepper, Mark A; Praetorius, Jeppe

    2013-01-01

    Background/Aims Aldosterone exerts multiple long-term effects in the distal renal tubules. The aim of this study was to establish a method for identifying proteins in these tubules that change in abundance by only 24-hours aldosterone administration. Methods Mice endogenously expressing green fluorescent protein (eGFP) in the connecting tubule and cortical collecting ducts were treated with a subcutaneous injection of 2.0 mg/kg aldosterone or vehicle (n=5), and sacrificed 24 hours later. Suspensions of single cells were obtained enzymatically, and eGFP positive cells were isolated by fluorescence activated cell sorting (FACS). Samples of 100 μg proteins were digested with trypsin and labeled with 8-plex iTRAQ reagents and processed for liquid chromatography tandem mass spectrometry (LC-MS/MS). Results FACS yielded 1.4 million cells per mouse. The LC-MS/MS spectra were matched to peptides by the SEQUEST search algorithm, which identified 3002 peptides corresponding to 506 unique proteins of which 20 significantly changed abundance 24-hours after aldosterone injection. Conclusion We find the method suitable and useful for studying hormonal effects on protein abundance in distal tubular segments. PMID:23428628

  5. Prognostic factors for death and survival with or without complications in cardiac arrest patients receiving CPR within 24 hours of anesthesia for emergency surgery

    PubMed Central

    Siriphuwanun, Visith; Punjasawadwong, Yodying; Lapisatepun, Worawut; Charuluxananan, Somrat; Uerpairojkit, Ketchada

    2014-01-01

    Purpose To determine prognostic factors for death and survival with or without complications in cardiac arrest patients who received cardiopulmonary resuscitation (CPR) within 24 hours of receiving anesthesia for emergency surgery. Patients and methods A retrospective cohort study approved by the Maharaj Nakorn Chiang Mai University Hospital Ethical Committee. Data used were taken from records of 751 cardiac arrest patients who received their first CPR within 24 hours of anesthesia for emergency surgery between January 1, 2003 and October 31, 2011. The reviewed data included patient characteristics, surgical procedures, American Society of Anesthesiologist (ASA) physical status classification, anesthesia information, the timing of cardiac arrest, CPR details, and outcomes at 24 hours after CPR. Univariate and polytomous logistic regression analyses were used to determine prognostic factors associated with the outcome variable. P-values of less than 0.05 were considered statistically significant. Results The outcomes at 24 hours were death (638/751, 85.0%), survival with complications (73/751, 9.7%), and survival without complications (40/751, 5.3%). The prognostic factors associated with death were: age between 13–34 years (OR =3.08, 95% CI =1.03–9.19); ASA physical status three and higher (OR =6.60, 95% CI =2.17–20.13); precardiopulmonary comorbidity (OR =3.28, 95% CI =1.09–9.90); the condition of patients who were on mechanical ventilation prior to receiving anesthesia (OR =4.11, 95% CI =1.17–14.38); surgery in the upper abdominal site (OR =14.64, 95% CI =2.83–75.82); shock prior to cardiac arrest (OR =6.24, 95% CI =2.53–15.36); nonshockable electrocardiography (EKG) rhythm (OR =5.67, 95% CI =1.93–16.62); cardiac arrest occurring in postoperative period (OR =7.35, 95% CI =2.89–18.74); and duration of CPR more than 30 minutes (OR =4.32, 95% CI =1.39–13.45). The prognostic factors associated with survival with complications were being greater

  6. 24-hour control of body temperature in rats. I. Integration of behavioral and autonomic effectors.

    PubMed

    Gordon, C J

    1994-07-01

    Some studies suggest that the nocturnal elevation in core temperature (Tc) of the rat is mediated by an elevation in the set point. The role of set point can be assessed if behavioral effectors are measured simultaneously with other thermoregulatory effectors and Tc over a 24-h period. Selected ambient temperature (STa) and motor activity (MA) were measured in rats housed in a temperature gradient system with a 12:12-h photoperiod (lights on 0600 h). Tc and heart rate (HR) were monitored by telemetry. During the light phase, STa, Tc, HR, and MA were relatively stable with values 29.0 degrees C, 37.1 degrees C, 310 beats/min, and 1-2 m/h, respectively. During the light-to-dark transition there were abrupt elevations in Tc, HR, and MA but no change in STa. STa decreased during the dark phase and reached a nadir of 23 degrees C at 0500 h. All variables recovered to basal levels within 3-4 h after the onset of the light phase. Overall, autonomic effectors control the elevation in Tc during the onset of the dark phase while behavioral effectors have little if any role. Behavioral thermoregulation is important in two ways: 1) the selection of cooler Ta values at night to prevent an excess elevation in Tc and 2) a preference for cooler Ta values before the light phase to facilitate the recovery of Tc. PMID:8048648

  7. New Advantage 24 contraceptive gel claims 24-hour effectiveness. But proposed FDA rule could put N-9 products to the test.

    PubMed

    1995-04-01

    Advantage 24 is a new contraceptive gel that makes use of bioadhesive technology to offer 24 hours of protection relying on the spermicide nonoxynol-9 (N-9) in lower concentrations. If a proposed US Food and Drug Administration (FDA) rule is enforced N-9 may be examined closely. The manufacturer, Whitehall-Robins Healthcare in New Jersey, stopped production of the Today contraceptive sponge because of the costs of complying with FDA standards. The Advantage 24 gel costs twice as much as the sponge. It is made in Switzerland and distributed by an Illinois company. Any vaginal contraceptive containing N-9 would be approved by the FDA as long as it complied with guidelines laid down in an FDA monograph. However, the registration of the gel could not be confirmed. The product uses a bioadhesive technology concept that natural substances adhere to epithelial and mucosal tissues in the body. Polycarbofil is mixed with water, N-9, and mineral oil to create an emulsion that allows for a time-release mechanism, but at any given time only 2 mg of N-9 is available to kill sperm. The final formula for Advantage 24 is 52.5 mg per dose. Too much N-9 can be toxic, as demonstrated by the Today sponge, which contained 1000 mg of N-9. In Kenya prostitutes using it frequently experienced 3 times as many genital lesions as those using a placebo. A study of Advantage 24 by a Miami laboratory involved 250 women, 22-45 years old, who had had prior tubal ligations. When the gel was applied 15-30 minutes before intercourse the efficacy rate was 98%; it was 91% for those applying it 12 hours before; and it was 86% when the gel was applied 24 hours ahead of time. FDA compliance officers are intrigued about the claim that the gel lasts 24 hours. However, if the claim is held up by research data, women will have an easily available, portable, efficient, aesthetic, and highly effective contraceptive. PMID:12347026

  8. Radio telemetry documents 24-hour feeding activity of wintering lesser scaup

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.; Sparks, D.W.

    1996-01-01

    We used radio telemetry to record 198 h of feeding behavior of five Lesser Scaup (Aythya affinis) on the Indiana Harbor Canal in northwestern Indiana during January and February 1994. Lesser Scaup fed for short periods of time intermittently during each 24-h period. Lesser Scaup fed a total of 96 min during the day and 226 min during the night. They fed more between sunset and midnight (31.9% of the period, P = 0.003) than between sunrise and noon (11.6%) or noon and sunset (19.5%); time spent feeding between midnight and sunrise (26.3%) did not differ from other times of day. Mean dive duration (22.9 ± 0.64 sec) did not vary by time of day (P = 0.186-0.744). These results are the first 24-h feeding activity reported for individually marked Lesser Scaup.

  9. A locomotor adaptation including explicit knowledge and removal of postadaptation errors induces complete 24-hour retention.

    PubMed

    Hussain, Sara J; Hanson, Angela S; Tseng, Shih-Chiao; Morton, Susanne M

    2013-08-01

    Locomotor patterns are generally very consistent but also contain a high degree of adaptability. Motor adaptation is a short-term type of learning that utilizes this plasticity to alter locomotor behaviors quickly and transiently. In this study, we used a variation of an adaptation paradigm in order to test whether explicit information as well as the removal of the visual error signal after adaptation could improve retention of a newly learned walking pattern 24 h later. On two consecutive days of testing, participants walked on a treadmill while viewing a visual display that showed erroneous feedback of swing times for each leg. Participants were instructed to use this feedback to monitor and adjust swing times so they appeared symmetric within the display. This was achieved by producing a novel interlimb asymmetry between legs. For both legs, we measured adaptation magnitudes and rates and immediate and 24-h retention magnitudes. Participants showed similar adaptation on both days but a faster rate of readaptation on day 2. There was complete retention of adapted swing times on the increasing leg (i.e., no evidence of performance decay over 24 h). Overall, these findings suggest that the inclusion of explicit information and the removal of the visual error signal are effective in inducing full retention of adapted increases in swing time over a moderate (24 h) interval of time. PMID:23741038

  10. The Automated Self-Administered 24-Hour Dietary Recall for Children, 2012 version, for youth aged 9 to 11 Years: A validation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to validate the 2012 version of the Automated Self-Administered 24-Hour Dietary Recall for Children (ASA24-Kids-2012), a self-administered web-based 24-hour dietary recall (24hDR) instrument, among children aged 9 to 11 years, in two sites using a quasiexperimental design. In one s...

  11. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CLEANING: 24 HOUR FOOD DIARY (HAND ENTRY) (UA-D-40.0)

    EPA Science Inventory

    The purpose of the SOP is to define the particular steps involved in cleaning the electronic data generated from data entry of the 24 Hour Food Diary. The procedure was developed to use during the Arizona NHEXAS project and the "Border" study. Keywords: data; cleaning; 24 hour ...

  12. The Relationship Between 24-Hour Symptoms and COPD Exacerbations and Healthcare Resource Use: Results from an Observational Study (ASSESS).

    PubMed

    Miravitlles, Marc; Worth, Heinrich; Soler-Cataluña, Juan José; Price, David; De Benedetto, Fernando; Roche, Nicolas; Godtfredsen, Nina S; van der Molen, Thys; Löfdahl, Claes-Göran; Padullés, Laura; Ribera, Anna

    2016-10-01

    This observational study assessed the relationship between nighttime, early-morning and daytime chronic obstructive pulmonary disease (COPD) symptoms and exacerbations and healthcare resource use. COPD symptoms were assessed at baseline in patients with stable COPD using a standardised questionnaire during routine clinical visits. Information was recorded on exacerbations and healthcare resource use during the year before baseline and during a 6-month follow-up period. The main objective of the analysis was to determine the predictive nature of current symptoms for future exacerbations and healthcare resource use. 727 patients were eligible (65.8% male, mean age: 67.2 years, % predicted forced expiratory volume in 1 second: 52.8%); 698 patients (96.0%) provided information after 6 months. Symptoms in any part of the day were associated with a prior history of exacerbations (all p < 0.05) and nighttime and early-morning symptoms were associated with the frequency of primary care visits in the year before baseline (both p < 0.01). During follow-up, patients with baseline symptoms during any part of the 24-hour day had more exacerbations than patients with no symptoms in each period (all p < 0.05); there was also an association between 24-hour symptoms and the frequency of primary care visits (all p ≤ 0.01). Although there was a significant association between early-morning and daytime symptoms and exacerbations during follow-up (both p < 0.01), significance was not maintained when adjusted for potential confounders. Prior exacerbations were most strongly associated with future risk of exacerbation. The results suggest 24-hour COPD symptoms do not independently predict future exacerbation risk. PMID:26983349

  13. Recalibration of Phonetic Categories by Lipread Speech: Measuring Aftereffects after a 24-Hour Delay

    ERIC Educational Resources Information Center

    Vroomen, Jean; Baart, Martijn

    2009-01-01

    Listeners hearing an ambiguous speech sound flexibly adjust their phonetic categories in accordance with lipread information telling what the phoneme should be (recalibration). Here, we tested the stability of lipread-induced recalibration over time. Listeners were exposed to an ambiguous sound halfway between /t/ and /p/ that was dubbed onto a…

  14. Normal 24-hour Ambulatory Esophageal pH Values in Koreans

    PubMed Central

    Moon, Won; Kim, Gyung Mi; Kim, Kyu Jong; Park, Seun Ja; Mun, Hyo Sung; Lee, Kang Dae

    2008-01-01

    Background/Aims Twenty-four-hour ambulatory esophageal pH monitoring is considered the gold standard for diagnosing gastroesophageal reflux disease. The aim of this study was to quantify normal distal esophageal acid parameters in healthy Koreans. Methods Thirty healthy adults who were not on medication and were free from gastrointestinal symptoms were analyzed. Ambulatory esophageal acid (pH <4) exposure parameters were recorded at 5 cm above the lower esophageal sphincter. Results The 95th percentiles for reflux parameters assessed in the distal esophagus were as follows: percentage of total time with pH <4, 5.10%; percentage of upright time with pH <4, 7.88%; percentage of supine time with pH <4, 4.00%; number of reflux episodes, 62.7; number of reflux episodes with pH <4 for >5 minutes, 5.3; and the longest single acid-exposure episode, 21.3 minutes. Conclusions Physiological gastroesophageal reflux occurs frequently in healthy Koreans. These data provide a reference range that could be utilized in studies involving Korean subjects. PMID:20485604

  15. Gender differences in the relationship between resting heart rate variability and 24-hour blood pressure variability.

    PubMed

    Thayer, Julian F; Sollers, John J; Friedman, Bruce H; Koenig, Julian

    2016-02-01

    The study explored the relationship between time- and frequency-domain indices of cardiac autonomic control and 24 h blood pressure variability (BPV) in a sample of healthy men and women. Vagally mediated cardiac control was inversely related to 24 h BPV, and measures of cardiac autonomic control were better predictors of systolic BPV in men and better predictors of diastolic BPV in women. These findings may help researchers to understand the disparity in cardiovascular disease morbidity and mortality between men and women. PMID:26415550

  16. Statistical quantification of 24-hour and monthly variabilities of spontaneous otoacoustic emission frequency in humans.

    PubMed

    Haggerty, H S; Lusted, H S; Morton, S C

    1993-10-01

    Previous evidence has suggested a relationship between spontaneous otoacoustic emissions (SOAEs) and established, biological cycles, although detailed statistical quantifications of the suggested relationships do not exist in the literature. In an attempt to statistically quantify the purported circadian and monthly influences on this phenomenon, two experiments were undertaken. The first experiment was conducted over eight weeks, investigating 31 SOAEs recorded from eight women and two men. Time series statistical analysis examined whether daily, weekly, and/or monthly cycles characterized SOAE frequency variability. Results yielded a significant monthly cycle for the majority of SOAEs recorded from the women but for none of the SOAEs recorded from the men. These results suggest the possibility that SOAE frequency fluctuation in women may be entrained to the monthly menstrual cycle. In the second experiment, hourly SOAE frequency stability was examined over a 24-h period to ascertain the nature of the daily frequency variation as precisely as possible. Four SOAEs from two subjects were examined, and time series analysis of these data included (1) modelling the autocorrelation structure of the measurements, (2) resolving each 24-h series of measurements into cyclical components of various periodicities, and (3) testing the statistical significance of given cycles within the spectrum of each series. Findings included a significant 24-h variability of frequency for each SOAE, suggesting the possibility of a circadian influence on frequency fluctuation. Results from the two experiments provide quantitative evidence supporting a hypothetical relationship between SOAEs and established, biological cycles. PMID:8276731

  17. Comparison of Interviewer-Administered and Automated Self-Administered 24-Hour Dietary Recalls in 3 Diverse Integrated Health Systems.

    PubMed

    Thompson, Frances E; Dixit-Joshi, Sujata; Potischman, Nancy; Dodd, Kevin W; Kirkpatrick, Sharon I; Kushi, Lawrence H; Alexander, Gwen L; Coleman, Laura A; Zimmerman, Thea P; Sundaram, Maria E; Clancy, Heather A; Groesbeck, Michelle; Douglass, Deirdre; George, Stephanie M; Schap, TusaRebecca E; Subar, Amy F

    2015-06-15

    Twenty-four-hour dietary recalls provide high-quality intake data but have been prohibitively expensive for large epidemiologic studies. This study's goal was to assess whether the web-based Automated Self-Administered 24-Hour Recall (ASA24) performs similarly enough to the standard interviewer-administered, Automated Multiple-Pass Method (AMPM) 24-hour dietary recall to be considered a viable alternative. In 2010-2011, 1,081 adults from 3 integrated health systems in Detroit, Michigan; Marshfield, Wisconsin; and Kaiser-Permanente Northern California participated in a field trial. A quota design ensured a diverse sample by sex, age, and race/ethnicity. Each participant was asked to complete 2 recalls and was randomly assigned to 1 of 4 protocols differing by type of recall and administration order. For energy, the mean intakes were 2,425 versus 2,374 kcal for men and 1,876 versus 1,906 kcal for women by AMPM and ASA24, respectively. Of 20 nutrients/food groups analyzed and controlling for false discovery rate, 87% were judged equivalent at the 20% bound. ASA24 was preferred over AMPM by 70% of the respondents. Attrition was lower in the ASA24/AMPM study group than in the AMPM/ASA24 group, and it was lower in the ASA24/ASA24 group than in the AMPM/AMPM group. ASA24 offers the potential to collect high-quality dietary intake information at low cost with less attrition. PMID:25964261

  18. Modeling of 24-hour glucose and insulin profiles in patients with type 2 diabetes mellitus treated with biphasic insulin aspart.

    PubMed

    Røge, Rikke M; Klim, Søren; Kristensen, Niels R; Ingwersen, Steen H; Kjellsson, Maria C

    2014-07-01

    Insulin therapy for diabetes patients is designed to mimic the endogenous insulin response of healthy subjects and thereby generate normal blood glucose levels. In order to control the blood glucose in insulin-treated diabetes patients, it is important to be able to predict the effect of exogenous insulin on blood glucose. A pharmacokinetic/pharmacodynamic model for glucose homoeostasis describing the effect of exogenous insulin would facilitate such prediction. Thus the aim of this work was to extend the previously developed integrated glucose-insulin (IGI) model to predict 24-hour glucose profiles for patients with Type 2 diabetes following exogenous insulin administration. Clinical data from two trials were included in the analysis. In both trials, 24-hour meal tolerance tests were used as the experimental setup, where exogenous insulin (biphasic insulin aspart) was administered in relation to meals. The IGI model was successfully extended to include the effect of exogenous insulin. Circadian variations in glucose homeostasis were assessed on relevant parameters, and a significant improvement was achieved by including a circadian rhythm on the endogenous glucose production in the model. The extended model is a useful tool for clinical trial simulation and for elucidating the effect profile of new insulin products. PMID:24446385

  19. The impact of kidney transplantation on 24-hour ambulatory blood pressure in end-stage renal disease patients.

    PubMed

    Lee, Myung Hyun; Ko, Kyung Min; Ahn, Seung Won; Bae, Myoung Nam; Choi, Bum Soon; Park, Cheol Whee; Kim, Yong-Soo; Yang, Chul Woo; Chung, Byung Ha

    2015-06-01

    In this study, we prospectively investigated the impact of kidney transplantation (KT) on the status of hypertension, including circadian rhythm in end-stage renal disease (ESRD) patients. We performed 24-hour ambulatory blood pressure (BP) monitoring and office BP measurement in 48 patients before and 1 year after KT. According to the nocturnal reduction in systolic BP (ΔSBP), the patients were divided into dippers, non-dippers, and reverse dippers. After KT, the mean BP value in office BP and 24-hour ambulatory BP monitoring did not change, but the proportion of patients taking anti-hypertensive drugs and the pill number significantly decreased. In contrast, the mean ΔSBP significantly decreased, and the proportion of non-dippers and reverse dippers did not decrease. Decrease in ΔSBP after KT was associated with inferior allograft function during follow-up. Our study suggests that KT improved the overall BP level, but it did not affect abnormal circadian rhythm in ESRD patients. PMID:26051924

  20. QTc interval prolongation in HIV-infected patients: a case–control study by 24-hour Holter ECG recording

    PubMed Central

    2012-01-01

    Background Aim of the study was to assess QTc interval by a 24-hour ECG recording in a group of HIV-infected individuals with a basal prolonged QTc. The risk factors associated with QTc prolongation and the indices of cardiovascular autonomic control were also evaluated. Methods A case–control study was performed using as cases 32 HIV-infected patients with prolonged (>440 msec) QTc interval as assessed by Holter ECG, and as controls 64 HIV-infected subjects with normal QTc interval. Autonomic function was evaluated by heart rate variability analysis during 24-hour recording. Results Duration of HIV disease was significantly longer among cases than among controls (p=0.04). Waist/hip ratio was also higher among cases than among controls (p=0.05). Frequency domain analysis showed the absence of physiologic decrease of low frequency (LF) in the night period in both cases and controls. The LF night in cases showed a statistically significant reduction when compared with controls (p=0.007). Conclusions In our study group, QTc interval prolongation was associated with a longer duration of HIV infection and with a greater waist/hip ratio. HIV patients with QTc interval prolongation and with a longer duration of HIV infection were more likely to have an impairment of parasympathetic and sympathetic cardiac component. PMID:23259665

  1. Enhanced carotid-cardiac baroreflex response and elimination of orthostatic hypotension 24 hours after acute exercise in paraplegics

    NASA Technical Reports Server (NTRS)

    Engelke, K. A.; Shea, J. D.; Doerr, D. F.; Convertino, V. A.

    1992-01-01

    To test the hypothesis that an acute bout of maximal exercise can ameliorate orthostatic hypotension consequent to prolonged wheelchair confinement, we evaluated heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure responses during 15 minutes of 70 degrees head-up tilt (HUT) in 10 paraplegic subjects 24 hours after arm crank exercise designed to elicit maximal effort, and during a control (no exercise) conditions. Additionally, the carotid baroreceptor stimulus-cardiac response relationship was determined by measurement of R-R interval during external application of graded pressures to the carotid sinuses. One week separated the treatment conditions. The maximum slope of the carotid-cardiac baroreflex response was increased (p = 0.049) by exercise (6.2 +/- 1.7 msec/mmHg) compared to control (3.3 +/- 0.6). During control HUT, HR increased from 61 +/- 1 to 90 +/- 7 bpm (p = 0.001) while SBP decreased from 118 +/- 5 to 106 +/- 9 mmHg (p = 0.025). During HUT 24 hours after exercise, HR increased from 60 +/- 2 to 90 +/- 4 bpm (p = 0.001), but the reduction in SBP was essentially eliminated (116 +/- 5 to 113 +/- 5 mmHg).

  2. Resistance training decreases 24-hour blood pressure in women with metabolic syndrome

    PubMed Central

    2013-01-01

    Background The purpose of this study was to verify the effects of eight weeks of resistance training (RT) on 24 hour blood pressure (BP) in patients with and without metabolic syndrome (MetS). Methods Seventeen women volunteered to participate in this study, 9 with MetS (37.0 ± 8.7 yrs; body mass 77.3 ± 9.7 kg; body mass index 30.3 ± 4.2 kg · m-2) and 8 without MetS (35.1 ± 7.2 yrs; body mass 61.3 ± 8.1 kg; body mass index 24.2 ± 2.5 kg · m-2). Individuals were subjected to eight weeks (3 times/week) of whole body RT comprised of one exercise for each main muscle group with three sets of 8–12 repetitions of each subject’s maximal load . A rest interval of one minute was allowed between sets and exercises. Twenty-four hour BP was measured by ambulatory blood pressure monitoring. Results Mean and diastolic night-time BP decreased (−3.9 mmHg, p = 0.04; -5.5 mmHg, p = 0.03, respectively) after eight weeks of training in MetS patients. This decrease was observed at 11:00 pm, 02:00 am (only diastolic), 07:00 am, and 6:00 pm. There was no training effect on BP in women without MetS. Conclusions Considering the elevation of BP as a contributor to the pathogenesis of MetS, and also to the increase of cardiovascular risk, this study supports RT as a non-pharmacological therapy in the management of BP control for MetS. PMID:23711286

  3. Specific Antivenom Ability in Neutralizing Hepatic and Renal Changes 24 Hours after Latrodectus dahli Envenomation

    PubMed Central

    Valikhanfard-Zanjani, Elham; Zare-Mirakabadi, Abbas; Oryan, Shahrbanoo; Goodarzi, Hamid Reza; Rajabi, Mahdise

    2016-01-01

    Background: Latrodectism, a syndrome caused by Latrodectus genus, is one of the clinical problems that occur predominantly in north east of Iran. Nowadays antivenom therapy has become the most useful treatment for animal bites; however there is still a controversy about route and time of antivenom administration in spider bite. The aim of the present study was to determine the efficacy of specific antivenom in neutralizing hepatic and renal symptoms 24 h after Latrodectus dahli envenomation. Methods: We selected a group of male New Zealand white rabbits, weighing 2±0.3 kg. The L. dahli venom (0.5 mg/kg) was injected subcutaneously. Specific antivenom (2.5 ml, I.V) was injected 24 h following venom injection. Blood sampling was performed before and 24 h after venom injection, as well within 24, 48 and 72 h after antivenom administration. Serum levels of (aspartate amino transferase (AST) alanine amino transferase (ALT), alkaline phosphatase (ALP), urea, bilirubin, creatinine and albumin were determined in all the sam. Results: Latrodectus dahli venom caused significant increase (P< 0.05) in all foresaid serum parameters. Antivenom reversed the AST, ALP, creatinine, urea and bilirubin to normal levels, but failed about ALT level, also non-significant decrease was observed in albumin levels. Conclusion: Antivenom administration 24 h after venom injection can greatly reverse symptoms caused by venom. Future studies in human beings should be conducted to assess the protection against the specific-Latrodectus anti-venom. PMID:27308281

  4. Trophoblast viability in perfused term placental tissue and explant cultures limited to 7-24 hours.

    PubMed

    Di Santo, S; Malek, A; Sager, R; Andres, A-C; Schneider, H

    2003-01-01

    Human term-placental culture techniques such as villous explant or dual perfusion are commonly used to study trophoblast function under control and experimentally manipulated conditions. We have compared trophoblast viability during perfusion and in explants cultured under various conditions by monitoring glucose consumption, protein synthesis and secretion, expression of differentiation-specific genes, induction of stress proteins and apoptotic cell death. The tissue was obtained from term-placentae of uncomplicated pregnancies after elective Caesarean delivery. We observed a severe loss of trophoblast viability in explants irrespective of the culture conditions used. Over 7 h of culture the amount of the differentiation specific placental hormones hCG, hPL and leptin accumulated in the medium dropped significantly. Analysis of their expression by semi-quantitative and real-time RT-PCR revealed that the down-regulation of expression occurred at the transcriptional level. This transcriptional repression was accompanied by induction of the stress-proteins RTP and BiP/GRP78. Analysis of apoptotic cell death by TUNEL assay and immunohistochemical detection of the caspase-3-specific degradation product of cytokeratin 18 revealed prominent cell death after 7 h of culture. These results are in contrast to the findings obtained in perfused placental tissue where, after 7 h of culture, hormone secretion, expression of stress proteins and cell death were similar as in native tissue. This difference between villous explant incubation and dual perfusion is also reflected by a significantly higher consumption of glucose in perfused tissue. PMID:13129686

  5. 24 hour forecast of the surface UV for the antipsoriatic heliotherapy in Poland.

    PubMed

    Krzyścin, J W; Guzikowski, J; Czerwińska, A; Lesiak, A; Narbutt, J; Jarosławski, J; Sobolewski, P S; Rajewska-Więch, B; Wink, J

    2015-07-01

    Analyses of the spectral and broad-band UV data collected at Belsk (20.79°E, 51.84°N), Poland, show that standard broad-band instrument, Solar Light (SL) 501A, could be used for measurements of both erythemal and antipsoriatic irradiance. A prognostic model is proposed for the next-day duration of outdoor exposure required to receive a dose, the so-called minimum antipsoriatic dose (MAD), equivalent to that received by standard antipsoriatic daily treatment in the phototherapy cabinet containing TL-01 fluorescent tubes. The model uses the 24 h forecast of the column amount of ozone (to predict next day clear sky UV irradiance), and low- and mid-level cloudiness (to estimate a reduction of the clear-sky UV irradiation due to clouds). The predicted duration of sunbathing required to receive a dose of 1 MAD matches the observed value, i.e. the correlation coefficients is 0.68. If the model predicts the antipsoriatic exposure over 1 MAD threshold the observed dose will be also above this threshold in 91% of cases. Thus, the model could be used for planning the next-day outdoor exposure to clear psoriasis. Hourly resolved maps, starting from 6 am up to 1 pm (GMT), showing the duration of antipsoriatic exposure over Poland are made public. The model provides a tool for a psoriatic patient to find the sunbathing starting time and its duration, which has the same healing potential as a single indoor phototherapy session. PMID:25911984

  6. 24-hour ambulatory blood pressure and renal disease in young subjects with type I diabetes.

    PubMed

    Garg, S K; Chase, H P; Icaza, G; Rothman, R L; Osberg, I; Carmain, J A

    1997-01-01

    Twenty-four hour ambulatory blood pressure (ABP) was evaluated in 150 teenage and young adults with insulin-dependent diabetes mellitus (IDDM) to define high-risk subjects who are likely to develop early diabetic nephropathy. Their age range was 16-28 years with diabetes of 3.5-25.8 years duration. All subjects had office blood pressure (BP) measured, wore an ABP monitor for 24 h, and collected two or more timed urine samples for albumin excretion rates (AERs). Eighty-six subjects had no elevation of AER (< 7.6 micrograms/min), 29 subjects had borderline elevations (7.6-20 micrograms/min), 24 subjects had microalbuminuria (20.1-200 micrograms/min), and 11 had macroalbuminuria (> 200 micrograms/min). Age, gender, duration of diabetes, and single office BP readings were similar in the four groups (p > 0.05, logistic regression). All 24-h ABP parameters were significantly higher in subjects with diabetes having AER values greater than 7.6 micrograms/min when compared with healthy age- and gender-matched nondiabetic controls (p < 0.05, Dunnett's t test). The percent of nighttime systolic and diastolic ABP readings above the 90th percentile of normal for age, gender, and race and the percent of readings in the hypertensive range (> 140/90) were significantly related with AERs (p < 0.01; logistic regression). A higher percentage of ABP values above the 90th percentile for age, gender, and ethnic group or of ABP readings above hypertensive levels (> or = 140/90) are associated with diabetic renal disease. PMID:9334907

  7. Albumin infusion in humans does not model exercise induced hypervolaemia after 24 hours

    NASA Technical Reports Server (NTRS)

    Haskell, A.; Gillen, C. M.; Mack, G. W.; Nadel, E. R.

    1998-01-01

    We rapidly infused 234 +/- 3 mL of 5% human serum albumin in eight men while measuring haematocrit, haemoglobin concentration, plasma volume (PV), albumin concentration, total protein concentration, osmolality, sodium concentration, renin activity, aldosterone concentration, and atrial natriuretic peptide concentration to test the hypotheses that plasma volume expansion and plasma albumin content expansion will not persist for 24 h. Plasma volume and albumin content were expanded for the first 6 h after infusion (44.3 +/- 1.9-47.2 +/- 2.0 mL kg-1 and 1.9 +/- 0.1-2.1 +/- 0.1 g kg-1 at pre-infusion and 1 h, respectively, P < 0.05), but by 24 h plasma volume and albumin content decreased significantly from 1 h post-infusion and were not different from pre-infusion (44.8 +/- 1.9 mL kg-1 and 1.9 +/- 0.1 g kg-1, respectively). Plasma aldosterone concentration showed a significant effect of time over the 24 h after infusion (P < 0.05), and showed a trend to decrease at 2 h after infusion (167.6 +/- 32.5(-1) 06.2 +/- 13.4 pg mL-1, P = 0.07). These data demonstrate that a 6.8% expansion of plasma volume and 10.5% expansion of plasma albumin content by infusion does not remain in the vascular space for 24 h and suggest a redistribution occurs between the intravascular space and interstitial fluid space.

  8. Influence of mild cold on the components of 24 hour thermogenesis in rats.

    PubMed Central

    Brown, D; Livesey, G; Dauncey, M J

    1991-01-01

    1. The influence of two weeks' acclimation to either 28 degrees C (thermal neutrality) or 21 degrees C (mild cold) on 24 h heat production and motor activity has been investigated in male Wistar rats. Food intake was controlled and provided as a single meal of approximately 170 kJ per day. Mathematical modelling was used to relate metabolic rate to measured movement and time of day. 2. For animals at thermal neutrality it was clear that metabolic rate increased during periods of substantial measured movement and returned to baseline during periods of minimal activity. Total heat production could therefore be divided into two components: underlying and movement-induced thermogenesis. 3. At 21 degrees C, a more complex model was needed. During periods of substantial activity, the relation between metabolic rate and movement was similar to that at 28 degrees C and total heat production could be divided into the same two components of underlying and movement-induced thermogenesis. However, during periods of prolonged inactivity, a different model was required, which included a component of extra metabolic activity, termed supplementary thermogenesis. By fitting this model to data at 28 and 21 degrees C, it was possible to partition 24 h heat production into the three possible sources of underlying, movement-induced and supplementary thermogenesis. 4. Total 24 h heat production was approximately 25% higher for rats at 21 compared with 28 degrees C (P less than 0.01) and underlying thermogenesis was approximately 20% higher for those in the mild cold (P less than 0.01). Measured movement was significantly reduced in the mild cold (P less than 0.05) although it was energetically less efficient since there was no difference in movement-induced thermogenesis, which accounted for 18 and 15% of total heat production at 28 and 21 degrees C respectively. Supplementary thermogenesis was observed only in the mild cold and it accounted for approximately 6% of 24 h heat production

  9. [Sequential changes in inflammatory and stress responses during 24-hour running].

    PubMed

    Shimizu, Tomomi; Imanishi, Akio; Sugimoto, Kenichi; Takeda, Nobuaki; Hirata, Ryuuzou; Andou, Takashi; Morikawa, Seiichi; Suzuki, Yoshio; Watanabe, Masayuki; Okuta, Miho; Kawana, Takayuki; Namikawa, Yui; Suzuki, Masato; Watanabe, Makino; Okada, Takao; Ohta, Makoto

    2011-10-01

    Running for an extended period of time can cause severe stress on the body, subsequently damaging skeletal muscle and resulting in changes in blood components. However, few reports have examined vital responses during and after running. This study analyzed inflammatory responses during and after running and changes in stress responses as determined by serial changes in blood components. Venous blood was obtained before starting, 6 h after starting, 12 h after starting, and immediately after finishing 24 h of continuous running. Samples were analyzed for high-sensitivity C-reactive protein (hsCRP), pentraxin 3 (ptx3), white blood cells (WBC), myoglobin, creatine kinase (CK), and hormones. Diet and physical activity were standardized 24 h before and after running. Subjects comprised 16 men who agreed to participate in experimental running on November 8 and 9, 2008, at Tokyo Gakugei University. Mean running distance was 151.32 +/- 32.1 km (range, 83.6-210.0 km) in 24 h. A significant increase in hsCRP was seen from 12 h after starting to completion. Compared to hsCRP, ptx3 gradually increased from before starting to after completion, showing a significant difference between pre and post-run ptx3 levels. WBC count increased significantly until 6 h after starting. Neutrophils in leukocytosis increased significantly during the first 6 h. Eosinophils decreased significantly over the course of the 24 h. Cortisol increased, and testosterone decreased significantly from 6 h after starting. Dehydroepiandrosterone sulfate (DHEA-S), myoglobin, and CK increased over the course of the 24 h. Reactive oxygen metabolites (d-ROMs) changed within the normal range though there was a significant decrease, and biological anti-oxidant potential (BAP) stabilized. Active natural killer cells decreased significantly after 24 h running. Biopyrrin (BPn) increased significantly. Changes in stress oxide were small both during and after running, and adaptation for antioxidation was good. DHEAS, a

  10. Exercise thermoregulation in men after 1 and 24-hours of 6 degrees head-down tilt

    NASA Technical Reports Server (NTRS)

    Ertl, A. C.; Dearborn, A. S.; Weidhofer, A. R.; Bernauer, E. M.; Greenleaf, J. E.

    2000-01-01

    BACKGROUND: Exercise thermoregulation is dependent on heat loss by increased skin blood flow (convective and conductive heat loss) and through enhanced sweating (evaporative heat loss). Reduction of plasma volume (PV), increased plasma osmolality, physical deconditioning, and duration of exposure to simulated and actual microgravity reduces the ability to thermoregulate during exercise. HYPOTHESIS: We hypothesized that 24 h of head down tilt (HDT24) would alter thermoregulatory responses to a submaximal exercise test and result in a higher exercise rectal temperature (Tre) when compared with exercise Tre after 1 h of head down tilt (HDT1). METHODS: Seven men (31+/-SD 6 yr, peak oxygen uptake (VpO2peak) of 44+/-6 ml x kg(-1) x min(-1)) were studied during 70 min of supine cycling at 58+/-SE 1.5% VO2peak at 22.0 degrees C Tdb and 47% rh. RESULTS: Relative to pre-tilt sitting chair rest data, HDT1 resulted in a 6.1+/-0.9% increase and HDT24 in a 4.3+/-2.3% decrease in PV (delta = 10.4% between experiments, p<0.05) while plasma osmolality remained unchanged (NS). Pre-exercise Tre was elevated after HDT24 (36.71 degrees C +/-0.06 HDT1 vs. 36.93 degrees C+/-0.11 HDT24, p<0.05). The 70 min of exercise did not alter this relationship (p<0.05) with respective end exercise increases in Tre to 38.01 degrees C and 38.26 degrees C (degrees = 1.30 degrees C (HDT1) and 1.33 degrees C (HDT24)). While there were no pre-exercise differences in mean skin temperature (Tsk), a significant (p<0.05) time x treatment interaction occurred during exercise: after min 30 in HDT24 the Tsk leveled off at 31.1 degrees C, while it continued to increase reaching 31.5 degrees C at min 70 in HDT1. A similar response (NS) occurred in skin blood velocity. Neither local sweating rates nor changes in body weight during exercise of -1.63+/-0.24 kg (HDT1) or - 1.33+/-0.09 kg (HDT24) were different (NS) between experiments. CONCLUSION: While HDT24 resulted in elevated pre-exercise Tre, reduced PV

  11. 24-hour urine protein

    MedlinePlus

    ... of fluid (dehydration) Any type of x-ray exam with dye (contrast material) within 3 days before the urine test Fluid from the vagina that gets into the urine Severe emotional stress Strenuous exercise Urinary tract infection

  12. Urine 24-hour volume

    MedlinePlus

    ... test results: Dehydration Any type of x-ray exam with dye (contrast material) within 3 days before the urine test Fluid from the vagina that gets into the urine Emotional stress Heavy exercise Urinary tract infection

  13. 24-hour care programs.

    PubMed

    Hergenrader, R

    1996-06-01

    Twenty-four-hour care programs, which combine group health programs with workers' compensation and disability benefits, hold considerable potential for cost savings and greater efficiency. This article explains these programs and uses a care history to show the savings they can achieve. PMID:10157798

  14. Urine 24-hour volume

    MedlinePlus

    ... in a day, such as: Creatinine Sodium Potassium Nitrogen Protein This test may also be done if ... disease Potassium urine test Sodium urine test Urea nitrogen urine test Urination - excessive amount Urine output - decreased ...

  15. 24-hour urine protein

    MedlinePlus

    ... a blockage of blood vessels, or other causes Multiple myeloma Healthy people may have higher than normal urine ... Distal Hemolytic anemia Macroglobulinemia of Waldenstrom Microalbuminuria test Multiple myeloma Nephrotic syndrome Proximal Wilson disease Update Date 11/ ...

  16. Prognostic Value of the 24-Hour Neurological Examination in Anterior Circulation Ischemic Stroke: A post hoc Analysis of Two Randomized Controlled Stroke Trials

    PubMed Central

    Rangaraju, Srikant; Frankel, Michael; Jovin, Tudor G.

    2016-01-01

    Background Early prognostication of long-term outcomes following ischemic stroke can facilitate medical decision-making. We hypothesized that the 24-hour National Institute of Health Stroke Scale (NIHSS) predicts 3-month clinical outcomes in anterior circulation stroke. Methods Secondary analyses of the Interventional Management of Stroke 3 (IMS3) and intravenous tissue plasminogen activator (IV tPA) for acute ischemic stroke [National Institute of Neurological Diseases and Stroke (NINDS) IV tPA] trials were performed. In participants with documented 24-hour NIHSS and 3-month Modified Rankin Scale (mRS), the predictive power of the 24-hour NIHSS and 24-hour NIHSS improvement for 3-month outcomes [mRS 0-2 and Barthel Index (BI) ≥95] was assessed. Percentages of good outcome (mRS 0-2 or BI ≥95) at 3, 6, and 12 months and mean quality of life (EQ5D™) index at 3 months across 24-hour NIHSS quartiles were compared. Results The majority of the study participants were included (IMS3 n = 587/656, NINDS IV tPA n = 619/624). The 24-hour NIHSS was correlated with 3-month mRS (R = 0.73) with excellent predictive power for mRS 0-2 [area under the curve (AUC) = 0.91] and BI ≥95 (AUC = 0.9) in both cohorts. A model with the 24-hour NIHSS alone correctly classified 82-84% of patients in both cohorts. The percentages of good outcomes at 3-12 months across 24-hour NIHSS quartiles were similar in both cohorts. mRS 0-2 was achieved by 75.6-77.7% of patients with 24-hour NIHSS ≤11 but by only 1.4-3.6% with 24-hour NIHSS ≥20. The EQ5D index at 3 months varied among NIHSS 0-4 (mean 0.86 ± 0.16), 5-11 (0.77 ± 0.18), and 12-19 (0.59 ± 0.26) quartiles. Conclusions The 24-hour NIHSS strongly predicts long-term stroke outcomes and is associated with quality of life. Its easy availability, reliability, and validity support its use as an early prognostic marker and surrogate of clinical outcome in ischemic stroke. PMID:27051408

  17. The prevalence of exercise-associated hyponatremia in 24-hour ultra-mountain bikers, 24-hour ultra-runners and multi-stage ultra-mountain bikers in the Czech Republic

    PubMed Central

    2014-01-01

    Background To assess the prevalence of exercise-associated hyponatremia (EAH) in two 24-hour mountain bike (MTB) (R1,R2), one 24-hour running (R3) and one multi-stage MTB (R4) races held in the Czech Republic in a cluster of four cross-sectional studies. Methods In 27 ultra-mountain bikers (ultra-MTBers), 12 ultra-runners, and 14 multi-stage MTBers, fluid intake, changes (Δ) in body mass, hematocrit, plasma volume, plasma [Na+], plasma [K+], plasma osmolality, urine [Na+], urine [K+], urine specific gravity, urine osmolality, K+/Na+ ratio in urine, transtubular potassium gradient and glomerular filtration rate were measured and calculated. The use of non-steroidal anti-inflammatory drugs and symptoms of EAH were recorded using post-race questionnaires. Results Of the 53 finishers, three (5.7%) developed post-race EAH, thereof one (3.7%) ultra-MTBer, one (8.3%) ultra-runner and one (7.1%) multi-stage MTBer. Plasma [Na+] decreased significantly (p < 0.001) only in R4. Urine osmolality (R1, R3, R4 p < 0.001; R2 p < 0.05) and glomerular filtration rate (p < 0.001) increased, and body mass decreased in all races (p < 0.05). Δ body mass was inversely related to the number of kilometers achieved (p < 0.001) in R2 where better ultra-MTBers tended to lose more weight. Δ body mass (p < 0.001) and %Δ body mass (p = 0.05) were positively related to lower post-race plasma [Na+] in R3 that was associated with increased loss in body mass. Fluid intake was positively related to race performance in R1 and R2 (R1: p = 0.04; R2: p = 0.01) where ultra-MTBers in R1 and R2 who drank more finished ahead of those who drank less. Post-race plasma [Na+] was negatively associated with race performance in ultra-MTBers in R2 (p < 0.05), similarly ultra-runners in R3 (p < 0.05) where finishers with more kilometres had lower post-race plasma [Na+]. Conclusions The prevalence of EAH in the Czech Republic was no higher compared to existing reports on ultra-endurance athletes in other countries

  18. Shortening the retention interval of 24-hour dietary recalls increases fourth-grade children’s accuracy for reporting energy and macronutrient intake at school meals

    PubMed Central

    Guinn, Caroline H.; Royer, Julie A.; Hardin, James W.; Mackelprang, Alyssa J.; Smith, Albert F.

    2010-01-01

    Background Accurate information about children’s intake is crucial for national nutrition policy and for research and clinical activities. To analyze accuracy for reporting energy and nutrients, most validation studies utilize the conventional approach which was not designed to capture errors of reported foods and amounts. The reporting-error-sensitive approach captures errors of reported foods and amounts. Objective To extend results to energy and macronutrients for a validation study concerning retention interval (elapsed time between to-be-reported meals and the interview) and accuracy for reporting school-meal intake, the conventional and reporting-error-sensitive approaches were compared. Design and participants/setting Fourth-grade children (n=374) were observed eating two school meals, and interviewed to obtain a 24-hour recall using one of six interview conditions from crossing two target periods (prior-24-hours; previous-day) with three interview times (morning; afternoon; evening). Data were collected in one district during three school years (2004–2005; 2005–2006; 2006–2007). Main outcome measures Report rates (reported/observed), correspondence rates (correctly reported/observed), and inflation ratios (intruded/observed) were calculated for energy and macronutrients. Statistical analyses performed For each outcome measure, mixed-model analysis of variance was conducted with target period, interview time, their interaction, and sex in the model; results were adjusted for school year and interviewer. Results Conventional approach — Report rates for energy and macronutrients did not differ by target period, interview time, their interaction, or sex. Reporting-error-sensitive approach — Correspondence rates for energy and macronutrients differed by target period (four P-values<0.0001) and the target-period by interview-time interaction (four P-values<0.0001); inflation ratios for energy and macronutrients differed by target period (four P

  19. Prediction of Appropriate Shocks Using 24-Hour Holter Variables and T-Wave Alternans After First Implantable Cardioverter-Defibrillator Implantation in Patients With Ischemic or Nonischemic Cardiomyopathy.

    PubMed

    Seegers, Joachim; Bergau, Leonard; Expósito, Pascal Muñoz; Bauer, Axel; Fischer, Thomas H; Lüthje, Lars; Hasenfuß, Gerd; Friede, Tim; Zabel, Markus

    2016-07-01

    In patients treated with implantable cardioverter defibrillator (ICD), prediction of both overall survival and occurrence of shocks is important if improved patient selection is desired. We prospectively studied the predictive value of biomarkers and indexes of cardiac and renal function and spectral microvolt T-wave alternans testing and 24-hour Holter variables in a population who underwent first ICD implantation. Consecutive patients in sinus rhythm with ischemic or dilated cardiomyopathy scheduled for primary or secondary prophylactic ICD implantation were enrolled. Exercise microvolt T-wave alternans and 24-hour Holter for number of ventricular premature contractions (VPCs), deceleration capacity, heart rate variability, and heart rate turbulence were done. Death of any cause and first appropriate ICD shock were defined as end points. Over 33 ± 15 months of follow-up, 36 of 253 patients (14%) received appropriate shocks and 39 of 253 patients (15%) died. Only 3 of 253 patients (1%) died after receiving at least 1 appropriate shock. In univariate analyses, New York Heart Association class, ejection fraction, N-terminal pro brain-type natriuretic peptide (NT-proBNP), renal function, ICD indication, deceleration capacity, heart rate variability, and heart rate turbulence were predictive of all-cause mortality and VPC number and deceleration capacity predicted first appropriate shock. NT-proBNP (≥1,600 pg/ml) was identified as the only independent predictor of all-cause mortality (hazard ratio 3.0, confidence interval 1.3 to 7.3, p = 0.014). In contrast, VPC number predicted appropriate shocks (hazard ratio 2.3, confidence interval 1.0 to 5.5, p = 0.047) as the only independent risk marker. In conclusion, NT-proBNP is a strong independent predictor of mortality in a typical prospective cohort of newly implanted patients with ICD, among many electrocardiographic and clinical variables studied. Number of VPCs was identified as a predictor of appropriate shocks

  20. Dietary quality varies according to data collection instrument: a comparison between a food frequency questionnaire and 24-hour recall.

    PubMed

    Rodrigues, Paulo Rogério Melo; de Souza, Rita Adriana Gomes; De Cnop, Mara Lima; Monteiro, Luana Silva; Coura, Camila Pinheiro; Brito, Alessandra Page; Pereira, Rosangela Alves

    2016-02-01

    The objective of this study was to assess the agreement between the Brazilian Healthy Eating Index - Revised (BHEI-R), estimated by a food frequency questionnaire (FFQ) and multiple 24-hour recalls (24h-R). The Wilcoxon paired test, partial correlations (PC), intraclass correlation coefficient (ICC), and Bland-Altman method were used. The total BHEI-R scores and its components ("total fruits", "whole fruits", "total vegetables", "integral cereals", "saturated fat", "sodium", and "energy intake derived from solid fat, added sugar, and alcoholic beverages") were statistically different, with the ICC and PC indicating poor concordance and correlation. The mean concordance estimated for the total BHEI-R and its components varied from 68% for "integral cereals" to 147% for "whole fruits". The suitable concordance limits were violated for most of the components of the BHEI-R. Poor concordance was observed between the BHEI-R estimated by the FFQ and by multiple 24h-R, which indicated a strong reliability of the BHEI-R on the instrument used to collect information on food consumption. PMID:26910251

  1. Relative prognostic value of rest thallium-201 imaging, radionuclide ventriculography and 24 hour ambulatory electrocardiographic monitoring after acute myocardial infarction

    SciTech Connect

    Hakki, A.H.; Nestico, P.F.; Heo, J.; Unwala, A.A.; Iskandrian, A.S.

    1987-07-01

    Rest thallium-201 scintigraphy, radionuclide ventriculography and 24 hour Holter monitoring are acceptable methods to assess myocardial necrosis, performance and electrical instability. This study examined the relative value of the three tests, when obtained a mean of 7 days after acute myocardial infarction, in predicting 1 year mortality in 93 patients. Planar thallium-201 images were obtained in three projections and were scored on a scale of 0 to 4 in 15 segments (normal score = 60). Patients were classified as having high risk test results as follows: thallium score less than or equal to 45 (33 patients), left ventricular ejection fraction less than or equal to 40% (51 patients) and complex ventricular arrhythmias on Holter monitoring (36 patients). During the follow-up of 6.4 +/- 3.4 months (mean +/- SD), 15 patients died of cardiac causes. All three tests were important predictors of survival by univariate Cox survival analysis; the thallium score, however, was the only important predictor by multivariate analysis. The predictive power of the thallium score was comparable with that of combined ejection fraction and Holter monitoring (chi-square = 21 versus chi-square = 22). Thus, rest thallium-201 imaging performed before hospital discharge provides important prognostic information in survivors of acute myocardial infarction which is comparable with that provided by left ventricular ejection fraction and Holter monitoring. Patients with a lower thallium score (large perfusion defects) are at high risk of cardiac death during the first year after infarction.

  2. Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome.

    PubMed

    Araos, Joaquín; Alegría, Leyla; García, Patricio; Damiani, Felipe; Tapia, Pablo; Soto, Dagoberto; Salomon, Tatiana; Rodriguez, Felipe; Amthauer, Macarena; Erranz, Benjamín; Castro, Gabriel; Carreño, Pamela; Medina, Tania; Retamal, Jaime; Cruces, Pablo; Bugedo, Guillermo; Bruhn, Alejandro

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support. PMID:27398166

  3. Extracorporeal membrane oxygenation improves survival in a novel 24-hour pig model of severe acute respiratory distress syndrome

    PubMed Central

    Araos, Joaquín; Alegría, Leyla; García, Patricio; Damiani, Felipe; Tapia, Pablo; Soto, Dagoberto; Salomon, Tatiana; Rodriguez, Felipe; Amthauer, Macarena; Erranz, Benjamín; Castro, Gabriel; Carreño, Pamela; Medina, Tania; Retamal, Jaime; Cruces, Pablo; Bugedo, Guillermo; Bruhn, Alejandro

    2016-01-01

    Extracorporeal membrane oxygenation (ECMO) is increasingly being used to treat severe acute respiratory distress syndrome (ARDS). However, there is limited clinical evidence about how to optimize the technique. Experimental research can provide an alternative to fill the actual knowledge gap. The purpose of the present study was to develop and validate an animal model of acute lung injury (ALI) which resembled severe ARDS, and which could be successfully supported with ECMO. Eighteen pigs were randomly allocated into three groups: sham, ALI, and ALI + ECMO. ALI was induced by a double-hit consisting in repeated saline lavage followed by a 2-hour period of injurious ventilation. All animals were followed up to 24 hours while being ventilated with conventional ventilation (tidal volume 10 ml/kg). The lung injury model resulted in severe hypoxemia, increased airway pressures, pulmonary hypertension, and altered alveolar membrane barrier function, as indicated by an increased protein concentration in bronchoalveolar fluid, and increased wet/dry lung weight ratio. Histologic examination revealed severe diffuse alveolar damage, characteristic of ARDS. Veno-venous ECMO was started at the end of lung injury induction with a flow > 60 ml/kg/min resulting in rapid reversal of hypoxemia and pulmonary hypertension. Mortality was 0, 66.6 and 16.6% in the SHAM, ALI and ALI + ECMO groups, respectively (p < 0.05). This is a novel clinically relevant animal model that can be used to optimize the approach to ECMO and foster translational research in extracorporeal lung support. PMID:27398166

  4. Canadian 24-Hour Movement Guidelines for Children and Youth: Exploring the perceptions of stakeholders regarding their acceptability, barriers to uptake, and dissemination.

    PubMed

    Faulkner, Guy; White, Lauren; Riazi, Negin; Latimer-Cheung, Amy E; Tremblay, Mark S

    2016-06-01

    Engaging stakeholders in the development of guidelines and plans for implementation is vital. The purpose of this study was to examine stakeholders' (parents, teachers, exercise professionals, paediatricians, and youth) perceptions of the Canadian 24-Hour Movement Behaviour Guidelines for Children and Youth ("Movement Guidelines"). Stakeholders (n = 104) engaged in semi-structured focus groups or interviews to discuss the perceived acceptability of the guidelines, potential barriers to implementation, and preferred methods and messengers of dissemination. A thematic analysis was conducted. Overall, there was consistent support across all stakeholder groups, with the exception of youth participants, for the Movement Guidelines. Stakeholders identified a range of barriers to the uptake of the guidelines including concerns with accurately defining key terms such as "recreational" screen time; everyday challenges such as financial and time constraints; and the possibility of the Movement Guidelines becoming just another source of stress and guilt for already busy and overwhelmed parents. Participants identified a range of recommended methods and messengers for future dissemination. School and medical settings were the most commonly recommended settings through which dissemination efforts should be delivered. Overall, participants representing a range of stakeholder groups were receptive to the new Movement Guidelines and endorsed their value. In complementing the Movement Guidelines, messaging and resources will need to be developed that address common concerns participants had regarding their dissemination and implementation. PMID:27306436

  5. Under-reporting of Energy Intake from 24-hour Dietary Recalls in the Korean National Health and Nutrition Examination Survey

    PubMed Central

    Kye, Seunghee; Kwon, Sung-Ok; Lee, Soon-Young; Lee, Jiyoon; Kim, Bok Hee; Suh, Hee-Jae; Moon, Hyun-Kyung

    2014-01-01

    Objectives Chronic degenerative diseases are closely related to daily eating habits, nutritional status, and, in particular, energy intake. In clarifying these relationships it is very important for dietary surveys to report accurate information about energy intake. This study attempted to identify the prevalence of the under-reporting of energy intake and its related characteristics based on the Korean National Health and Nutrition Examination Survey conducted in the years 2007–2009. Methods The present study analyzed dietary intake data from 15,133 adults aged ≥19 years using 24-hour dietary recalls. Basal metabolic rates were calculated from the age- and gender-specific equations of Schofield and under-reporting was defined as an energy intake <0.9, represented by the ratio of energy intake to estimated basal metabolic rate. Results Under-reporters (URs) accounted for 14.4% of men and 23.0% of women and the under-reporting rate was higher in the age group 30–49 years for both men and women. The results from an analysis of the age-specific socioeconomic characteristics of participants classified as URs showed that under-reporting was high in women living alone and in women with only elementary school education or no education. The results from an analysis of the health-specific characteristics of URs showed that a large proportion of URs had poor self-rated health or were obese, or both, compared with non-URs. The proportion of participants who consumed less than the estimated average requirements for nutrients was significantly higher in URs compared with non-URs. Conclusion The under-reporting of energy intake was associated with age, gender, education level, income level, household status (single-person or multi-person), self-rated health, physical activity, and obesity. PMID:24955317

  6. Variants in the LEPR gene are nominally associated with higher BMI and lower 24 hour energy expenditure in Pima Indians

    PubMed Central

    Traurig, Michael; Perez, Jessica; Ma, Lijun; Bian, Li; Kobes, Sayuko; Hanson, Robert L.; Knowler, William C.; Krakoff, Jonathan; Bogardus, Clifton; Baier, Leslie J.

    2012-01-01

    Genome-wide association studies (GWASs) have been used to search for susceptibility genes for type 2 diabetes and obesity in the Pima Indians, a population with high a prevalence of both diseases. In these studies, a variant (rs2025804) in the LEPR gene was nominally associated with BMI in 1082 subjects (P=0.03 adjusted for age, sex, birth year, and family membership). Therefore the LEPR and leptin overlapping transcript (LEPROT) genes were selected for further sequencing and genotyping in larger population-based samples for association analyses with obesity-related phenotypes. Selected variants (n=80) spanning these genes were genotyped in a sample of full-heritage Pima Indians (n=2842) and several common variants including rs2025804 were nominally associated with BMI (P=0.05-0.003 adjusted for age, sex, birth year, and family membership). Four common tag variants associated with BMI in the full-heritage Pima Indian sample were genotyped in a second sample of mixed-heritage Native Americans (n=2969) and 3 of the variants showed nominal replication (P=0.03-0.006 adjusted as above and additionally for Indian heritage). Combining both samples provided the strongest evidence for association (adjusted P=0.0003-0.0001). A subset of these individuals (n=403) had been metabolically characterized for predictors of obesity and the BMI risk alleles for the variants tagged by rs2025804 were also associated with lower 24 hour energy expenditure as assessed in a human respiratory chamber (P=0.0007 adjusted for age, sex, fat mass, fat free mass, activity, and family membership). We conclude that common non-coding variation in the LEPR gene is associated with higher BMI and lower energy expenditure in Native Americans. PMID:22810975

  7. 24-hour human urine and serum profiles of bisphenol A: Evidence against sublingual absorption following ingestion in soup.

    PubMed

    Teeguarden, Justin G; Twaddle, Nathan C; Churchwell, Mona I; Yang, Xiaoxia; Fisher, Jeffrey W; Seryak, Liesel M; Doerge, Daniel R

    2015-10-15

    Extensive first-pass metabolism of ingested bisphenol A (BPA) in the gastro-intestinal tract and liver restricts blood concentrations of bioactive BPA to <1% of total BPA in humans and non-human primates. Absorption of ingested BPA through non-metabolizing tissues of the oral cavity, recently demonstrated in dogs, could lead to the higher serum BPA concentrations reported in some human biomonitoring studies. We hypothesized that the extensive interaction with the oral mucosa by a liquid matrix, like soup, relative to solid food or capsules, might enhance absorption through non-metabolizing oral cavity tissues in humans, producing higher bioavailability and higher serum BPA concentrations. Concurrent serum and urine concentrations of d6-BPA, and its glucuronide and sulfate conjugates, were measured over a 24hour period in 10 adult male volunteers following ingestion of 30μg d6-BPA/kg body weight in soup. Absorption of d6-BPA was rapid (t1/2=0.45h) and elimination of the administered dose was complete 24h post-ingestion, evidence against any tissue depot for BPA. The maximum serum d6-BPA concentration was 0.43nM at 1.6h after administration and represented <0.3% of total d6-BPA. Pharmacokinetic parameters, pharmacokinetic model simulations, and the significantly faster appearance half-life of d6-BPA-glucuronide compared to d6-BPA (0.29h vs 0.45h) were evidence against meaningful absorption of BPA in humans through any non-metabolizing tissue (<1%). This study confirms that typical exposure to BPA in food produces picomolar to subpicomolar serum BPA concentrations in humans, not nM concentrations reported in some biomonitoring studies. PMID:25620055

  8. Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep.

    PubMed

    Tremblay, Mark S; Carson, Valerie; Chaput, Jean-Philippe; Connor Gorber, Sarah; Dinh, Thy; Duggan, Mary; Faulkner, Guy; Gray, Casey E; Gruber, Reut; Janson, Katherine; Janssen, Ian; Katzmarzyk, Peter T; Kho, Michelle E; Latimer-Cheung, Amy E; LeBlanc, Claire; Okely, Anthony D; Olds, Timothy; Pate, Russell R; Phillips, Andrea; Poitras, Veronica J; Rodenburg, Sophie; Sampson, Margaret; Saunders, Travis J; Stone, James A; Stratton, Gareth; Weiss, Shelly K; Zehr, Lori

    2016-06-01

    Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed. PMID:27306437

  9. Jack Healy Remembers - Anecdotal Evidence for the Origin of the Approximate 24-hour Urine Sampling Protocol Used for Worker Bioassay Monitoring

    SciTech Connect

    Carbaugh, Eugene H.

    2008-10-01

    The origin of the approximate 24-hour urine sampling protocol used at Hanford for routine bioassay is attributed to an informal study done in the mid-1940s. While the actual data were never published and have been lost, anecdotal recollections by staff involved in the initial bioassay program design and administration suggest that the sampling protocol had a solid scientific basis. Numerous alternate methods for normalizing partial day samples to represent a total 24-hour collection have since been proposed and used, but no one method is obviously preferred.

  10. Arctic tipping points: governance in turbulent times.

    PubMed

    Young, Oran R

    2012-02-01

    Interacting forces of climate change and globalization are transforming the Arctic. Triggered by a non-linear shift in sea ice, this transformation has unleashed mounting interest in opportunities to exploit the region's natural resources as well as growing concern about environmental, economic, and political issues associated with such efforts. This article addresses the implications of this transformation for governance, identifies limitations of existing arrangements, and explores changes needed to meet new demands. It advocates the development of an Arctic regime complex featuring flexibility across issues and adaptability over time along with an enhanced role for the Arctic Council both in conducting policy-relevant assessments and in promoting synergy in interactions among the elements of the emerging Arctic regime complex. The emphasis throughout is on maximizing the fit between the socioecological features of the Arctic and the character of the governance arrangements needed to steer the Arctic toward a sustainable future. PMID:22270707

  11. VALIDATION OF THREE FOOD FREQUENCY QUESTIONNAIRES AND 24-HOUR RECALLS WITH SERUM CAROTENOID LEVELS IN A SAMPLE OF AFRICAN-AMERICAN ADULTS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The validity of self-reported fruit and vegetable intake in minority populations has not been adequately established. In this study, the authors examined the association of three food frequency questionnaires (FFQs) and 24-hour dietary recalls with serum carotenoid levels. Approximately 1,000 Africa...

  12. Validation of the automated self-administered 24-hour dietary recall for children (ASA24-Kids) among 9- to 11-year-old youth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our purpose was to validate ASA24-Kids-2012, a self-administered web-based 24-hour dietary recall (24hDR) among 9- to 11-year-old children. Sixty-nine children in two sites participated in the study. In one site, trained staff observed and recorded types and portions of foods and drinks consumed by ...

  13. Identifying nutrients that are under-reported by an automated 24-hour dietary recall method in overweight and obese women after weight loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Underreporting of energy intake by 15-50% is a common problem in dietary assessment. Evidence suggests overweight/obese respondents are more likely to under-report than normal weight. This study compared Automated Self-Administered 24-hour recall (ASA24)-reported dietary intake to true intake in ove...

  14. 24-HOUR DIFFUSIVE SAMPLING OF 1,3-BUTADIENE IN AIR ONTO CARBONPAK X SOLID ADSORBENT WITH THEMAL DESORPTION/GC/MS ANALYSIS - FEASIBILITY STUDIES

    EPA Science Inventory

    Diffusive sampling of 1,3-butadiene for 24 hours onto the graphitic adsorbent Carbopack X contained in a stainless steel tube badge (6.3 mm OD, 5 mm ID, and 90 mm in length) with analysis by thermal desorption/GC/MS has been evaluated in controlled tests. A test matrix of 42 tr...

  15. 49 CFR 375.607 - What must I do if I am able to tender a shipment for final delivery more than 24 hours before a...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 5 2013-10-01 2013-10-01 false What must I do if I am able to tender a shipment... INTERSTATE COMMERCE; CONSUMER PROTECTION REGULATIONS Transportation of Shipments § 375.607 What must I do if I am able to tender a shipment for final delivery more than 24 hours before a specified date?...

  16. The effect of low level radiofrequency electromagnetic radiation on the excretion rates of stress hormones in operators during 24-hour shifts.

    PubMed

    Vangelova, K; Israel, M; Mihaylov, S

    2002-06-01

    The aim of the study was to investigate the effect of long term exposure to low level radiofrequency (RF) electromagnetic (EM) radiation on the excretion rates of stress hormones in satellite station operators during 24-hour shifts. Twelve male operators at a satellite station for TV communications and space research were studied during 24-hour shifts. Dosimetric evaluation of the exposure was carried out and showed low level exposure with specific absorption of 0.1127 J.kg-1. A control group of 12 unexposed male operators with similar job task and the same shift system were studied, too. The 11-oxycorticosteroids (11-OCS), adrenaline and noradrenaline were followed by spectrofluorimetric methods on 3-hour intervals during the 24-hour shifts. The data were analyzed by tests for interindividual analysis, Cosinor analysis and analysis of variance (ANOVA). Significant increase in the 24-hour excretion of 11-OCS and disorders in its circadian rhythm, manifested by increase in the mesor, decrease in the amplitude and shift in the acrophase were found in the exposed operators. The changes in the excretion rates of the catecholamines were significant and showed greater variability of both variables. The long term effect of the exposure to low-level RF EM radiation evoked pronounced stress reaction with changes in the circadian rhythm of 11-OCS and increased variability of catecholamines secretion. The possible health hazards associated with observed alteration in the stress system need to be clarified by identification of their significance and prognostic relevance. PMID:12096679

  17. The Automated Self-Administered 24-hour dietary recall (ASA24): A resource for researchers, clinicians, and educators from the National Cancer Institute

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive evidence has demonstrated that 24-hour dietary recalls (24HDRs) provide high-quality dietary intake data with minimal bias, making them the preferred tool for monitoring the diets of populations and, increasingly, for studying diet and disease associations. Traditional 24HDRs, however, are...

  18. External Beam Radiotherapy Plus 24-Hour Continuous Infusion of Gemcitabine in Unresectable Pancreatic Carcinoma: Long-Term Results of a Phase II Study

    SciTech Connect

    Mattiucci, Gian C.; Morganti, Alessio G.; Valentini, Vincenzo; Ippolito, Edy; Alfieri, Sergio; Antinori, Armando; Crucitti, Antonio; D'Agostino, Giuseppe R.; Di Lullo, Liberato; Luzi, Stefano; Mantini, Giovanna; Smaniotto, Daniela; Doglietto, Gian B.; Cellini, Numa

    2010-03-01

    Purpose: To evaluate the efficacy of gemcitabine-based chemoradiation (CT-RT) in treating patients (pts) affected by locally advanced pancreatic cancers (LAPC). Methods and Materials: Weekly gemcitabine (100 mg/m{sup 2}) was given as a 24-hour infusion during the course of three-dimensional radiotherapy (50.4 Gy to the tumor, 39.6 Gy to the nodes). After CT-RT, pts received five cycles of sequential chemotherapy with gemcitabine (1000 mg/m{sup 2}; 1, 8, q21). Response rate was assessed according to World Health Organization criteria 6 weeks after the end of CT-RT. Local control (LC), time to progression (TTP), metastases-free survival (MFS), and overall survival (OS) were analyzed by the Kaplan Meier method. Results: Forty pts (male/female 22/18; median age 62 years, range, 36-76) were treated from 2000 to 2005. The majority had T4 tumour (n = 34, 85%), six pts (15%) had T3 tumour. Sixteen pts (40%) were node positive at diagnosis. Grade 3-4 acute toxicity was observed in 21 pts (52.5%). Thirty pts (75%) completed the treatment schedule. A clinical response was achieved in 12 pts (30%). With a median follow-up of 76 months (range, 32-98), 2-year LC was 39.6% (median, 12 months), 2-year TTP was 18.4% (median, 10 months), and 2-year MFS was 29.7% (median, 10 months). Two-year OS (25%; median, 15.5 months) compared with our previous study on 5-fluorouracil-based CT-RT (2.8%) was significantly improved (p <0.001). Conclusions: Gemcitabine CT-RT seems correlated with improved outcomes. Healthier patients who are likely to complete the treatment schedule may benefit most from this therapy.

  19. Global Molecular and Morphological Effects of 24-Hour Chromium(VI) Exposure on Shewanella oneidensis MR-1

    PubMed Central

    Chourey, Karuna; Thompson, Melissa R.; Morrell-Falvey, Jennifer; VerBerkmoes, Nathan C.; Brown, Steven D.; Shah, Manesh; Zhou, Jizhong; Doktycz, Mitchel; Hettich, Robert L.; Thompson, Dorothea K.

    2006-01-01

    The biological impact of 24-h (“chronic”) chromium(VI) [Cr(VI) or chromate] exposure on Shewanella oneidensis MR-1 was assessed by analyzing cellular morphology as well as genome-wide differential gene and protein expression profiles. Cells challenged aerobically with an initial chromate concentration of 0.3 mM in complex growth medium were compared to untreated control cells grown in the absence of chromate. At the 24-h time point at which cells were harvested for transcriptome and proteome analyses, no residual Cr(VI) was detected in the culture supernatant, thus suggesting the complete uptake and/or reduction of this metal by cells. In contrast to the untreated control cells, Cr(VI)-exposed cells formed apparently aseptate, nonmotile filaments that tended to aggregate. Transcriptome profiling and mass spectrometry-based proteomic characterization revealed that the principal molecular response to 24-h Cr(VI) exposure was the induction of prophage-related genes and their encoded products as well as a number of functionally undefined hypothetical genes that were located within the integrated phage regions of the MR-1 genome. In addition, genes with annotated functions in DNA metabolism, cell division, biosynthesis and degradation of the murein (peptidoglycan) sacculus, membrane response, and general environmental stress protection were upregulated, while genes encoding chemotaxis, motility, and transport/binding proteins were largely repressed under conditions of 24-h chromate treatment. PMID:16957260

  20. Global Molecular and Morphological Effects of 24-Hour Chromium(VI)Exposure on Shewanella oneidensis MR-1

    SciTech Connect

    Chourey, Karuna; Thompson, Melissa R; Morrell-Falvey, Jennifer L; Verberkmoes, Nathan C; Brown, Steven D; Shah, Manesh B; Zhou, Jizhong; Doktycz, Mitchel John; Hettich, Robert {Bob} L; Thompson, Dorothea K

    2006-01-01

    The biological impact of 24-h ("chronic") chromium(VI) [Cr(VI) or chromate] exposure on ShewanellaoneidensisMR-1 was assessed by analyzing cellular morphology as well as genome-wide differential gene and protein expression profiles. Cells challenged aerobically with an initial chromate concentration of 0.3 mM in complex growth medium were compared to untreated control cells grown in the absence of chromate. At the 24-h time point at which cells were harvested for transcriptome and proteome analyses, no residual Cr(VI) was detected in the culture supernatant, thus suggesting the complete uptake and/or reduction of this metal by cells. In contrast to the untreated control cells, Cr(VI)-exposed cells formed apparently aseptate, nonmotile filaments that tended to aggregate. Transcriptome profiling and mass spectrometry-based proteomic charac terization revealed that the principal molecular response to 24-h Cr(VI) exposure was the induction of prophage-related genes and their encoded products as well as a number of functionally undefined hypothetical genes that were located within the integrated phage regions of the MR-1 genome. In addition, genes with annotated functions in DNA metabolism, cell division, biosynthesis and degradation of the murein (pepti doglycan) sacculus, membrane response, and general environmental stress protection were upregulated, while genes encoding chemotaxis, motility, and transport/binding proteins were largely repressed under conditions of 24-h chromate treatment.

  1. 22 CFR 161.5 - Major decision points and timing.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Major decision points and timing. 161.5 Section... decision points and timing. (a) The responsible action officer shall ensure compliance with these...) Environmental analysis and review of a proposed Departmental action shall be conducted as early as...

  2. 22 CFR 161.5 - Major decision points and timing.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Major decision points and timing. 161.5 Section... decision points and timing. (a) The responsible action officer shall ensure compliance with these...) Environmental analysis and review of a proposed Departmental action shall be conducted as early as...

  3. 22 CFR 161.5 - Major decision points and timing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Major decision points and timing. 161.5 Section... decision points and timing. (a) The responsible action officer shall ensure compliance with these...) Environmental analysis and review of a proposed Departmental action shall be conducted as early as...

  4. 22 CFR 161.5 - Major decision points and timing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Major decision points and timing. 161.5 Section... decision points and timing. (a) The responsible action officer shall ensure compliance with these...) Environmental analysis and review of a proposed Departmental action shall be conducted as early as...

  5. 22 CFR 161.5 - Major decision points and timing.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Major decision points and timing. 161.5 Section... decision points and timing. (a) The responsible action officer shall ensure compliance with these...) Environmental analysis and review of a proposed Departmental action shall be conducted as early as...

  6. Urinary electrolyte excretion in 24 hours and blood pressure in the INTERSALT Study. I. Estimates of reliability. The INTERSALT Cooperative Research Group.

    PubMed

    Dyer, A R; Shipley, M; Elliott, P

    1994-05-01

    This is the first of two reports dealing with the reliability of measurements of 24-hour urinary electrolyte excretion and blood pressure and estimates of electrolyte-blood pressure associations in INTERSALT, an international study of the relations of electrolyte excretion and other factors to blood pressure, involving more than 10,000 persons from 52 centers in 32 countries. This first report describes methods for estimating reliability, taking into account age and sex, and provides estimates for several urinary variables, blood pressure, and pulse rate. The second report (Am J Epidemiol 1994; 139:940-51) uses these estimates of reliability and multivariate procedures to correct multiple regression coefficients from regressions of blood pressure on 24-hour urinary sodium and potassium excretion, body mass index, and alcohol intake for "regression dilution bias." Age- and sex-adjusted estimates of reliability were computed from data on 805 INTERSALT participants with repeat measurements. These estimates ranged from 0.37 to 0.40 for 24-hour urinary sodium, from 0.47 to 0.52 for potassium, from 0.32 to 0.36 for the sodium:potassium ratio, from 0.64 to 0.69 for calcium, from 0.59 to 0.65 for creatinine, from 0.49 to 0.57 for urinary volume, from 0.49 to 0.51 for magnesium, from 0.58 to 0.62 for pulse, from 0.69 to 0.74 for systolic blood pressure, and from 0.63 to 0.67 for diastolic blood pressure. In addition, estimates of within- and between-person covariances among electrolytes indicated that about half of the observed covariance for sodium and potassium excretion in a single 24-hour urine collection was due to within-person covariation in excretion. PMID:8166143

  7. Investigation of cattle methane production and emission over a 24-hour period using measurements of δ13C and δD of emitted CH4 and rumen water

    NASA Astrophysics Data System (ADS)

    Bilek, R. S.; Tyler, S. C.; Kurihara, M.; Yagi, K.

    2001-07-01

    We have conducted a series of experiments to determine the effects different diets, including the addition of unsaturated fatty acids, had on isotopic signatures of CH4 emissions from dairy cattle. Measurements of emitted δ13CH4, δ13CO2, and δD-CH4 were made on gases collected over a 24-hour period from animal chambers containing individual Holstein cows. Some measurements of δD-H2O from samples collected directly from the rumen were also made. We observed variation in δ13CH4 values with time after feeding and a correlation in δ13C between emitted gases and diet. The average δ13CH4 value, which includes all samples of emitted gases, was -70.6±4.9‰ (n = 57). Measurements of δD-CH4 over the 24-hour sampling period had an average value of -357.8±15.0‰ (n = 56). These δD measurements are among the lightest reported for CH4 produced by cattle. Our cattle data indicate that hydrogen incorporated into the CH4 produced by CO2 reduction in high H2 concentration environments is fractionated to a greater degree than that incorporated in systems with relatively low H2 conditions, such as wetlands. Our results support bacterial studies that have demonstrated large hydrogen fractionation in high H2 concentration systems during methanogenesis.

  8. Effects of ranitidine and cisapride on acid reflux and oesophageal motility in patients with reflux oesophagitis: a 24 hour ambulatory combined pH and manometry study.

    PubMed

    Inauen, W; Emde, C; Weber, B; Armstrong, D; Bettschen, H U; Huber, T; Scheurer, U; Blum, A L; Halter, F; Merki, H S

    1993-08-01

    The effect of ranitidine and cisapride on acid reflux and oesophageal motility was investigated in 18 patients with endoscopically verified erosive reflux oesophagitis. Each patient was treated with placebo, ranitidine (150 mg twice daily), and ranitidine (150 mg twice daily) plus cisapride (20 mg twice daily) in a double blind, double dummy, within subject, three way cross over design. Oesophageal acidity and motility were monitored under ambulatory conditions for 24 hours on the fourth day of treatment, after a wash out period of 10 days during which patients received only antacids for relief of symptoms. Acid reflux was monitored by a pH electrode located 5 cm above the lower oesophageal sphincter. Intraoesophageal pressure was simultaneously recorded from four transducers placed 20, 15, 10, and 5 cm above the lower oesophageal sphincter. Upright reflux was three times higher than supine reflux (median (range) 13.3 (3.7-35.0)% v 3.7 (0-37.6)% of the time with pH < 4.0, p < 0.01, n = 18). Compared with placebo, ranitidine decreased total reflux (from 10.0 (3.2-32.6)% to 6.4 (1.2-22.9)%, p < 0.01), upright reflux (p < 0.05), supine reflux (p < 0.001), and postprandial reflux (p < 0.01), but did not affect oesophageal motility. The combination of ranitidine with cisapride further diminished the acid reflux found with ranitidine--that is, cisapride led to an additional reduction of total reflux (from 6.4 (1.2-22.9)% to 3.7 (1.0-12.7)%, p < 0.01), supine reflux (p < 0.05), and postprandial reflux (p < 0.05). Cisapride also reduced both the number (p<0.01) and duration (p<0.05) of reflux episodes and significantly increased amplitude, duration, and propagation velocity of oesophageal contractions (p<0.05) but did not affect the number of contractions. The findings show that the 30% reduction of oesophageal acid exposure achieved by a conventional dose of ranitidine (150 mg twice daily) can be improved to more than 60% by combination with cisapride (20 mg twice daily

  9. Factors Associated With High Sodium Intake Based on Estimated 24-Hour Urinary Sodium Excretion: The 2009-2011 Korea National Health and Nutrition Examination Survey.

    PubMed

    Hong, Jae Won; Noh, Jung Hyun; Kim, Dong-Jun

    2016-03-01

    Although reducing dietary salt consumption is the most cost-effective strategy for preventing progression of cardiovascular and renal disease, policy-based approaches to monitor sodium intake accurately and the understanding factors associated with excessive sodium intake for the improvement of public health are lacking. We investigated factors associated with high sodium intake based on the estimated 24-hour urinary sodium excretion, using data from the 2009 to 2011 Korea National Health and Nutrition Examination Survey (KNHANES). Among 21,199 adults (≥19 years of age) who participated in the 2009 to 2011 KNHANES, 18,000 participants (weighted n = 33,969,783) who completed urinary sodium and creatinine evaluations were analyzed in this study. The 24-hour urinary sodium excretion was estimated using Tanaka equation. The mean estimated 24-hour urinary sodium excretion level was 4349 (4286-4413) mg per day. Only 18.5% (weighted n = 6,298,481/3,396,973, unweighted n = 2898/18,000) of the study participants consumed less the 2000 mg sodium per day. Female gender (P < 0.001), older age (P < 0.001), total energy intake ≥50 percentile (P < 0.005), and obesity (P < 0.001) were associated with high sodium intake, even after adjusting for potential confounders. Senior high school/college graduation in education and managers/professionals in occupation were associated with lower sodium intake (P < 0.001). According to hypertension management status, those who had hypertension without medication consumed more sodium than those who were normotensive. However, those who receiving treatment for hypertension consumed less sodium than those who were normotensive (P < 0.001). The number of family members, household income, and alcohol drinking did not affect 24-hour urinary sodium excretion. The logistic regression analysis for the highest estimated 24-hour urinary sodium excretion quartile (>6033 mg/day) using the abovementioned variables

  10. Novel description of the 24-hour circadian rhythms of brachial versus central aortic blood pressure and the impact of blood pressure treatment in a randomized controlled clinical trial: The Ambulatory Central Aortic Pressure (AmCAP) Study.

    PubMed

    Williams, Bryan; Lacy, Peter S; Baschiera, Fabio; Brunel, Patrick; Düsing, Rainer

    2013-06-01

    Elevated brachial blood pressure (BP) is associated with increased cardiovascular risk and predicts morbidity and mortality in humans. Recently, 24-hour ambulatory BP monitoring and assessment of central aortic BP have been introduced to improve BP phenotyping. The Ambulatory Central Aortic Pressure (AmCAP) study combines these approaches and describes, for the first time, the diurnal patterns of simultaneously measured 24-hour ambulatory brachial and central pressures in a prespecified substudy embedded within a clinical trial of BP lowering in patients with hypertension. Twenty-four-hour ambulatory brachial and central pressure measurements were acquired using a tonometer mounted into the articulating strap of a wristwatch-like device (BPro) in 171 participants with hypertension recruited into the ASSERTIVE (AliSkiren Study of profound antihypERtensive efficacy in hyperTensIVE patients) trial. Participants were randomly assigned to BP lowering with either aliskiren 300 mg QD or telmisartan 80 mg QD for 12 weeks. Ambulatory brachial and central BP was measured in all participants both at baseline and at study end. Brachial and central BP both demonstrated typical diurnal patterns with lower pressures at night. However, night time was associated with smaller reductions in central relative to brachial pressure and decreased pulse pressure amplification (P<0.0001 for both). These effects were not modulated after BP lowering and were maintained after adjustment for day and night-time BP and heart rate (P=0.02). This study demonstrates that brachial and central pressure show different diurnal patterns, which are not modulated by BP-lowering therapy, with relatively higher night-time central pressures. These novel data indicate that night-time central BP may provide prognostic importance and warrants further investigation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00865020. PMID:23630950

  11. Planning time-optimal robotic manipulator motions and work places for point-to-point tasks

    NASA Technical Reports Server (NTRS)

    Dubowsky, S.; Blubaugh, T. D.

    1989-01-01

    A method is presented which combines simple time-optimal motions in an optimal manner to yield the minimum-time motions for an important class of complex manipulator tasks composed of point-to-point moves such as assembly, electronic component insertion, and spot welding. This method can also be used to design manipulator actions and work places so that tasks can be completed in minimum time. The method has been implemented in a computer-aided design software system. Several examples are presented. Experimental results show the method's validity and utility.

  12. Development and validity of a 3-day smartphone-assisted 24-hour recall to assess beverage consumption in a Chinese population: a randomized cross-over study

    PubMed Central

    Smith, Lindsey P.; Hua, Jenna; Seto, Edmund; Du, Shufa; Zang, Jiajie; Zou, Shurong; Popkin, Barry M.; Mendez, Michelle A.

    2014-01-01

    This paper addresses the need for diet assessment methods that capture the rapidly changing beverage consumption patterns in China. The objective of this study was to develop a 3-day smartphone-assisted 24-hour recall to improve the quantification of beverage intake amongst young Chinese adults (n=110) and validate, in a small subset (n=34), the extent to which the written record and smartphone-assisted recalls adequately estimated total fluid intake, using 24-hour urine samples. The smartphone-assisted method showed improved validity compared to the written-assisted method, when comparing reported total fluid intake to total urine volume. However, participants reported consuming fewer beverages on the smartphone-assisted method compared to the written-assisted method, primarily due to decreased consumption of traditional zero-energy beverages (i.e. water, tea) in the smartphone-assisted method. It is unclear why participants reported fewer beverages in the smartphone-assisted method than the written-assisted method. One possibility is that participants found the smartphone method too cumbersome, and responded by decreasing beverage intake. These results suggest that smartphone-assisted 24-hour recalls perform comparably but do not appear to substantially improve beverage quantification compared to the current written record based approach. In addition, we piloted a beverage screener to identify consumers of episodically consumed SSBs. As expected, a substantially higher proportion of consumers reported consuming SSBs on the beverage screener compared to either recall type, suggesting that a beverage screener may be useful in characterizing consumption of episodically consumed beverages in China’s dynamic food and beverage landscape. PMID:25516327

  13. Ambulatory 24-hour cardiac oxygen consumption and blood pressure-heart rate variability: effects of nebivolol and valsartan alone and in combination.

    PubMed

    Izzo, Joseph L; Khan, Safi U; Saleem, Osman; Osmond, Peter J

    2015-07-01

    We compared an angiotensin receptor blocker (valsartan; VAL), a beta-blocker (nebivolol; NEB) and the combination of NEB/VAL with respect to 24-hour myocardial oxygen consumption (determined by 24-hour ambulatory heart rate-central systolic pressure product [ACRPP]) and its components. Subjects with hypertension (systolic blood pressure >140 or diastolic blood pressure >90; n = 26) were studied in a double-blinded, double-dummy, forced-titration, crossover design with 3 random-order experimental periods: VAL 320 mg, NEB 40 mg, and NEB/VAL 320/40 mg daily. After 4 weeks of each drug, ambulatory pulse wave analysis (MobilOGraph) was performed every 20 minutes for 24 hours. All three treatments resulted in nearly identical brachial and central systolic blood pressures. NEB alone or in combination with VAL resulted in lower ACRPP (by 11%-14%; P < .001 each) and heart rate (by 18%-20%; P < .001 each) compared with VAL, but stroke work (ACRPP per beat) was lower with VAL. Relative and adjusted variability (standard deviation and coefficient of variation) of heart rate were also lower with NEB and NEB/VAL than VAL. Results in African Americans, the majority subpopulation, were similar to those of the entire treatment group. We conclude that the rate-slowing effects of NEB cause ambulatory cardiac myocardial oxygen consumption to be lower with NEB monotherapy or NEB/VAL combination therapy than with VAL monotherapy. NEB/VAL is not superior to NEB alone in controlling heart rate, blood pressure, or ACRPP. Heart rate variability but not ACRPP variability is reduced by NEB or the combination NEB/VAL. There is no attenuation of beta-blocker-induced rate-slowing effects of in African Americans. PMID:26116459

  14. Clustering space-time interest points for action representation

    NASA Astrophysics Data System (ADS)

    Jin, Sou-Young; Choi, Ho-Jin

    2013-12-01

    This paper presents a novel approach to represent human actions in a video. Our approach deals with the limitation of local representation, i.e. space-time interest points, which cannot adequately represent actions in a video due to lack of global information about geometric relationships among interest points. It adds the geometric relationships to interest points by clustering interest points using squared Euclidean distances, followed by using a minimum hexahedron to represent each cluster. Within each video, we build a multi-dimensional histogram based on the characteristics of hexahedrons in the video for recognition. The experimental results show that the proposed representation is powerful to include the global information on top of local interest points and it successfully increases the accuracy of action recognition.

  15. Validation of the Portuguese self-administered computerised 24-hour dietary recall among second-, third- and fourth-grade children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current methods for assessing children's dietary intake, such as interviewer-administered 24-h dietary recall (24-h DR), are time consuming and resource intensive. Self-administered instruments offer a low-cost diet assessment method for use with children. The present study assessed the validity of ...

  16. What a Difference a Day Makes: Change in Memory for Newly Learned Word Forms over 24 Hours

    ERIC Educational Resources Information Center

    McGregor, Karla K.

    2014-01-01

    Purpose: This study explored the role of time and retrieval experience in the consolidation of word forms. Method: Participants were 106 adults trained on 16 novel word-referent pairs, then tested immediately and 24 hr later for recognition and recall of word forms. In the interim, tests were repeated 2 hr or 12 hr after training, or not at all,…

  17. What a Difference a Day Makes: Change in Memory for Newly Learned Word Forms Over 24 Hours

    PubMed Central

    McGregor, Karla K.

    2014-01-01

    Purpose This study explored the role of time and retrieval experience in the consolidation of word forms. Method Participants were 106 adults trained on 16 novel word-referent pairs, then tested immediately and 24 hr later for recognition and recall of word forms. In the interim, tests were repeated 2 hr or 12 hr after training, or not at all, thus varying the amount and timing of retrieval experience. Results Recognition accuracy was stable and speed improved over the 24-hr period. But these manifestations of consolidation did not depend on interim retrieval experience; in fact, the 2-hr interim test interfered with improvements in speed. In contrast, the number of word forms recalled increased only with interim retrieval experiences, and the 12-hr interim test was more advantageous to recall than the 2-hr test. Conclusions After a word form is encoded, it can become stronger with time. Retrieval experience can also strengthen the trace, but, if retrieval occurs when the memory is still labile, it can be disruptive. This complex interplay between retrieval experience and time holds implications for measuring learning outcomes and for scheduling practice in classrooms and clinics. PMID:24845578

  18. Variability of Urinary Concentrations of Bisphenol A in Spot Samples, First Morning Voids, and 24-Hour Collections

    PubMed Central

    Wong, Lee-Yang; Bishop, Amber M.; Calafat, Antonia M.

    2011-01-01

    Background: Human exposure to bisphenol A (BPA) is widespread. After exposure, BPA is rapidly metabolized and eliminated in urine. Therefore, there is considerable within-person and between-person variability of BPA concentrations in spot urine samples. However, no information exists on the within-day variability of urinary BPA concentrations. Objectives: We examined the between-person and within-person and between-day and within-day variability in the urinary BPA concentrations of eight adults who collected all voids for 1 week to investigate the impact of sampling strategy in the exposure assessment of BPA using spot, first morning, or 24-hr urine collections. Methods: We determined the urinary concentrations of BPA using on-line solid-phase extraction coupled to isotope dilution high-performance liquid chromatography/tandem mass spectrometry. Results: The between-day and within-person variability was the primary contributor to the total variance both for first morning voids (77%) and 24-hr urine collections (88%). For the spot collections, we observed considerable within-day variance (70%), which outweighed the between-person (9%) and between-day and within-person (21%) variances. Conclusions: Regardless of the type of void (spot, first morning, 24-hr collection), urinary BPA concentrations for a given adult changed considerably—both within a day and for the 7 days of the study period. Single 24-hr urine collections accurately reflect daily exposure but can misrepresent variability in daily exposures over time. Of interest, when the population investigated is sufficiently large and samples are randomly collected relative to meal ingestion times and bladder emptying times, the single spot–sampling approach may adequately reflect the average exposure of the population to BPA. PMID:21406337

  19. Diurnal 24-hour rhythm in ambulatory heart rate variability during the day shift in rotating shift workers.

    PubMed

    Yoshizaki, Takahiro; Kawano, Yukari; Tada, Yuki; Hida, Azumi; Midorikawa, Toru; Hasegawa, Kohe; Mitani, Takeshi; Komatsu, Taiki; Togo, Fumiharu

    2013-06-01

    Circadian variation in cardiac autonomic nervous system activity and behavior during the day shifts of shift workers has not hitherto been clarified. This study examined diurnal 24-h variation in heart rate variability (HRV), sleep-wake cycle, physical activity, and food intake during the day shift in rotating shift workers. The subjects were female nurses and caregivers working at a health care facility (14 day workers and 13 rotating shift workers). Each subject was asked to undergo 24-h electrocardiograph and step count recordings. Coarse graining spectral analysis was used for approximately 10-min segments of HRV (600 beats) to derive the total power (TOT: >0.04 Hz), integrated power in the low-frequency (LF: 0.04-0.15 Hz) and high-frequency (HF: >0.15 Hz) ranges, the ratio of HF power to TOT (HF nu), and the ratio of LF power to HF power (LF/HF). Double cosinor analysis was used to obtain 24-h and 12-h period variations in variables of HRV and physical activity. While no difference was found in the acrophases of either period for step counts or in the 12-h period of HRV variables between the groups, the acrophases of the 24-h period for HRV variables were delayed by 1.3 to 5.5 h in rotating shift workers, and their differences in HF power, HF nu, and LF/HF reached a significant level (p < 0.05). On the days of the experiment, retiring time, waking up time, total time in bed, sleep efficiency, and mealtimes and energy intake for each diet did not differ between the groups. These results suggest that there is a possibility of an abnormal phase angle between circadian variation in cardiac autonomic nervous system activity and the sleep-wake cycle during the day shift in shift workers. PMID:23735502

  20. Value of a 24-hour image (four-phase bone scan) in assessing osteomyelitis in patients with peripheral vascular disease

    SciTech Connect

    Alazraki, N.; Dries, D.; Datz, F.; Lawrence, P.; Greenberg, E.; Taylor, A. Jr.

    1985-07-01

    The delayed images of the four-phase /sup 99m/Tc phosphonate bone scan are compared with the delayed images of the three-phase study in patients with diabetes mellitus and/or peripheral vascular disease and suspected osteomyelitis. Three-phase bone imaging includes an immediate postinjection radionuclide angiogram, a blood-pool image, and delayed static images to 7 hr. The four-phase study adds a 24-hr static image. The scan is positive for osteomyelitis if images show progressively increasing lesion to background activity ratios over time. The results of analyzing 21 three- and four-phase bone scans in 17 patients were correlated with clinical course, cultures, and/or x-rays, gallium scans, and CT scans. The accuracy of four-phase bone imaging for diagnosing osteomyelitis was 85%; for three phase, 80%. Sensitivity for four phase was 80%; specificity was 87%. Sensitivity for three phase was 100%; specificity was 73%.

  1. Cross-Sectional Study of 24-Hour Urinary Electrolyte Excretion and Associated Health Outcomes in a Convenience Sample of Australian Primary Schoolchildren: The Salt and Other Nutrients in Children (SONIC) Study Protocol

    PubMed Central

    Baxter, Janet R; Campbell, Karen J; Riddell, Lynn J; Rigo, Manuela; Liem, Djin Gie; Keast, Russell S; He, Feng J; Nowson, Caryl A

    2015-01-01

    Background Dietary sodium and potassium are involved in the pathogenesis of cardiovascular disease. Data exploring the cardiovascular outcomes associated with these electrolytes within Australian children is sparse. Furthermore, an objective measure of sodium and potassium intake within this group is lacking. Objective The primary aim of the Salt and Other Nutrient Intakes in Children (“SONIC”) study was to measure sodium and potassium intakes in a sample of primary schoolchildren located in Victoria, Australia, using 24-hour urine collections. Secondary aims were to identify the dietary sources of sodium and potassium, examine the association between these electrolytes and cardiovascular risk factors, and assess children’s taste preferences and saltiness perception of manufactured foods. Methods A cross-sectional study was conducted in a convenience sample of schoolchildren attending primary schools in Victoria, Australia. Participants completed one 24-hour urine collection, which was analyzed for sodium, potassium, and creatinine. Completeness of collections was assessed using collection time, total volume, and urinary creatinine. One 24-hour dietary recall was completed to assess dietary intake. Other data collected included blood pressure, body weight, height, waist and hip circumference. Children were also presented with high and low sodium variants of food products and asked to discriminate salt level and choose their preferred variant. Parents provided demographic information and information on use of discretionary salt. Descriptive statistics will be used to describe sodium and potassium intakes. Linear and logistic regression models with clustered robust standard errors will be used to assess the association between electrolyte intake and health outcomes (blood pressure and body mass index/BMI z-score and waist circumference) and to assess differences in taste preference and discrimination between high and low sodium foods, and correlations between

  2. Treatment of burns in the first 24 hours: simple and practical guide by answering 10 questions in a step-by-step form

    PubMed Central

    2012-01-01

    Residents in training, medical students and other staff in surgical sector, emergency room (ER) and intensive care unit (ICU) or Burn Unit face a multitude of questions regarding burn care. Treatment of burns is not always straightforward. Furthermore, National and International guidelines differ from one region to another. On one hand, it is important to understand pathophysiology, classification of burns, surgical treatment, and the latest updates in burn science. On the other hand, the clinical situation for treating these cases needs clear guidelines to cover every single aspect during the treatment procedure. Thus, 10 questions have been organised and discussed in a step-by-step form in order to achieve the excellence of education and the optimal treatment of burn injuries in the first 24 hours. These 10 questions will clearly discuss referral criteria to the burn unit, primary and secondary survey, estimation of the total burned surface area (%TBSA) and the degree of burns as well as resuscitation process, routine interventions, laboratory tests, indications of Bronchoscopy and special considerations for Inhalation trauma, immediate consultations and referrals, emergency surgery and admission orders. Understanding and answering the 10 questions will not only cover the management process of Burns during the first 24 hours but also seems to be an interactive clear guide for education purpose. PMID:22583548

  3. Effect of current and lifetime posttraumatic stress disorder on 24-hour urinary catecholamines and cortisol: results from the Mind Your Heart Study

    PubMed Central

    Wingenfeld, Katja; Whooley, Mary A.; Neylan, Thomas C.; Otte, Christian; Cohen, Beth E.

    2014-01-01

    Summary Posttraumatic stress disorder (PTSD) is associated with an increased risk of cardiovascular disease and several other chronic illnesses. Alterations in the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis in PTSD might contribute to these associations but findings regarding SNS and HPA activity in PTSD are heterogeneous. We measured 24-hour urinary catecholamines and cortisol in a large cohort of adult outpatients recruited from 2 Veterans Affairs medical centers. 24-hour urinary norepinephrine, epinephrine, dopamine and cortisol were measured by tandem mass spectrometry. Lifetime and current PTSD were assessed with the Clinician Administered PTSD Scale using DSM-IV-TR criteria. Out of 613 participants, 199 (32.5%) had current PTSD, 100 (16.3%) had lifetime but not current PTSD, and 314 (51.2%) never had PTSD. Patients with current PTSD had significantly higher norepinephrine secretion compared to those without PTSD. Patients in the lifetime PTSD group exhibited lower cortisol values compared to those without PTSD. Participants who never had PTSD showed the lowest norepinephrine and the highest cortisol values. All results remained stable when controlling for potentially confounding variables. This study provides evidence for increased norepinephrine secretion and decreased cortisol in PTSD. Future longitudinal studies are needed to determine whether these changes contribute to adverse health outcomes in patients with PTSD. PMID:25459895

  4. Estimation of 24-hour thyroid uptake of I-131 sodium iodide using a 5-minute uptake of technetium-99m pertechnetate

    SciTech Connect

    Smith, J.J.; Croft, B.Y.; Brookeman, V.A.; Teates, C.D. )

    1990-02-01

    The authors have developed a method to estimate the 24-hour sodium iodide thyroid uptake based on a 5-minute Tc-99m pertechnetate thyroid uptake using the equation: Estimated Iodide Uptake = 17.72*In(Pertechnetate Uptake) + 30.40. This estimation has a correlation coefficient of 0.90. It is based on a data pool of 44 patients who underwent I-131 and Tc-99m studies within 2 weeks of each other from 1978-1988, with established diagnoses as follows: 12 euthyroid, 6 hyperthyroid with multinodular goiters, 15 hyperthyroid with diffuse goiters, 4 with subacute thyroiditis, and 7 unknown. The population consisted of 30 women and 14 men with a mean age of 52.0 +/- 17.5 years; this sample was screened for use of thyroid hormone, propylthiouracil, and radiographic contrast. The authors believe this estimation method is of value whenever a 24-hour iodide uptake is desired, and where speed and minimizing radiation dose are factors. This method is strongly recommended for thyroid uptake evaluation before I-131 therapy.

  5. [THE INFLUENCE OF CYTOFLAVIN AND CARDIOXIPIN ON THE PARAMETERS OF 24-HOUR ARTERIAL PRESSURE MONITORING IN PATIENTS WITH CHRONIC CEREBRAL CIRCULATION INSUFFICIENCY, ARTERIAL HYPERTENSION AND HYPERCHOLESTEROLEMIA].

    PubMed

    Vodop'ianova, O A; Moiseeva, I Ia; Rodina, O P; Kustikova, I N; Antropova, N V

    2015-01-01

    This comparative study of the influence of cytoflavin and cardioxipin on the parameters of 24-hour arterial pressure monitoring in 56 patients with chronic cerebral circulation insufficiency, arterial hypertension and hypercholesterolemia included 32 women and 24 men aged 42-72 years divided into 3 groups matchedfor the stage of diseases, age, sex, severity of AH, total cholesterol level, and antihypertensive therapy. Patients of group 1 were treated without cytoflavin and cardioxipin. Those in group 2 received daily i/v droplet infusion of 10 mg/kg cardioxipin (20-30 droplets/min). Patients of group 3 were given daily i/v droplet infusion of 10 ml cytoflavin in 200 ml 0.9% sodium chloride solution for 10 days. 24-hour arterial pressure monitoring was used to estimate the influence of the two drugs on systolic and diastolic pressure, its daily rhythm, AP variability and frequency of elevation. The study showed that both therapeutic modalities improved daily AP rhythm as manifested in a significant increase of the number of patients with the dipper rhythm and a decrease in the number of systolic/diastolic non-dipper patients. Moreover cytoflavin significantly decreased the number of systolic over-dippers compared with control group. PMID:26117922

  6. The effect of the new "24 hour alcohol licensing law" on the incidence of facial trauma in London.

    PubMed

    El-Maaytah, Mohammed; Smith, Samantha F; Jerjes, Waseem; Upile, Tahwinder; Petrie, Aviva; Kalavrezos, Nicholas; Ayliffe, Peter; Newman, Lawrence; Hopper, Colin; Lloyd, Tim

    2008-09-01

    On 24 November 2005 the new 2003 Licensing Act was implemented. It permits licensed premises to close at different times under English and Welsh law, rather than at 2300h as under the previous law. The aim of this study was to assess whether head and neck trauma secondary to alcohol-associated assaults had increased, decreased, or stayed the same since the introduction of the act. Data were collected from the Accident and Emergency Department, University College Hospital, attendance databases for two six-month periods: 24 November 2004 to 30 April 2005, and 24 November 2005 to 30 April 2006. There were 1102 attendances for head and neck trauma secondary to alcohol-associated assaults during the six months before the introduction of the 2003 Licensing Act and 730 such attendances during the similar period after the introduction of the law, with fewer cases in each corresponding month during the later period. There were more cases at weekends than on weekdays during both periods. There were fewer cases but more at weekends in 2005-6 than in 2004-5 (423, 58% compared with 584, 53%, respectively). Neither rainfall nor temperature had any influence on the results. The 2003 licensing Act seems to have reduced the number of attendances at the A&E department for head and neck trauma secondary to alcohol associated assaults. PMID:18406500

  7. [24-hour work: the interaction of stress and changes in the sleep-wake cycle in the police force].

    PubMed

    Garbarino, Sergio

    2014-01-01

    Disruption in police officers. In recent years there has been a widespread growth in services, available regardless of time or day organization (24/7 service) and a diffuse increase in their use, both in work and private lives, generally ignoring the importance of a regular sleep organization. Police officers - often need to work extended shifts and long hours under highly stressful conditions, which results in reduced levels of safety and operational effectiveness. In numerous studies, perceived stress has been found to correlate with both subjective and objective disturbances in sleep. Consequently, excessive daytime sleepiness is one of the most frequent health and safety hazards that police officers have to deal with. Sleep deprivation affects performance outcomes through a wide range of cognitive domains. Sleepiness and fatigue, caused by sleep loss, extended work and wakefulness, circadian misalignment and sleep disorders are major causes of workplace human errors, incidents, and accidents. Therefore, prevention of sleep loss, high levels of stress and fatigue is a key factor to consider when assessing emergency intervention. In order to combat fatigue and sleepiness, a 30-90 minutes nap before night shift could be a viable option. PMID:25558741

  8. Dipper and non-dipper blood pressure 24-hour patterns: circadian rhythm-dependent physiologic and pathophysiologic mechanisms.

    PubMed

    Fabbian, Fabio; Smolensky, Michael H; Tiseo, Ruana; Pala, Marco; Manfredini, Roberto; Portaluppi, Francesco

    2013-03-01

    Neuroendocrine mechanisms are major determinants of the normal 24-h blood pressure (BP) pattern. At the central level, integration of the major driving factors of this temporal variability is mediated by circadian rhythms of monoaminergic systems in conjunction with those of the hypothalamic-pituitary-adrenal, hypothalamic-pituitary-thyroid, opioid, renin-angiotensin-aldosterone, plus endothelial systems and specific vasoactive peptides. Humoral secretions are typically episodic, coupled either to sleep and/or the circadian endogenous (suprachiasmatic nucleus) central pacemaker clock, but exhibiting also weekly, monthly, seasonal, and annual periodicities. Sleep induction and arousal are influenced also by many hormones and chemical substances that exhibit 24-h variation, e.g., arginine vasopressin, vasoactive intestinal peptide, melatonin, somatotropin, insulin, steroids, serotonin, corticotropin-releasing factor, adrenocorticotropic hormone, thyrotropin-releasing hormone, endogenous opioids, and prostaglandin E2, all with established effects on the cardiovascular system. As a consequence, physical, mental, and pathologic stimuli that activate or inhibit neuroendocrine effectors of biological rhythmicity may also interfere with, or modify, the temporal BP structure. Moreover, immediate adjustment to exogenous components/environment demands by BP rhythms is modulated by the circadian-time-dependent responsiveness of biological oscillators and their neuroendocrine effectors. This knowledge contributes to a better understanding of the pathophysiology of abnormalities of the 24-h BP pattern and level and their correction through circadian rhythm-based chronotherapeutic strategies. PMID:23002916

  9. Accessing the exceptional points of parity-time symmetric acoustics

    PubMed Central

    Shi, Chengzhi; Dubois, Marc; Chen, Yun; Cheng, Lei; Ramezani, Hamidreza; Wang, Yuan; Zhang, Xiang

    2016-01-01

    Parity-time (PT) symmetric systems experience phase transition between PT exact and broken phases at exceptional point. These PT phase transitions contribute significantly to the design of single mode lasers, coherent perfect absorbers, isolators, and diodes. However, such exceptional points are extremely difficult to access in practice because of the dispersive behaviour of most loss and gain materials required in PT symmetric systems. Here we introduce a method to systematically tame these exceptional points and control PT phases. Our experimental demonstration hinges on an active acoustic element that realizes a complex-valued potential and simultaneously controls the multiple interference in the structure. The manipulation of exceptional points offers new routes to broaden applications for PT symmetric physics in acoustics, optics, microwaves and electronics, which are essential for sensing, communication and imaging. PMID:27025443

  10. Accessing the exceptional points of parity-time symmetric acoustics

    NASA Astrophysics Data System (ADS)

    Shi, Chengzhi; Dubois, Marc; Chen, Yun; Cheng, Lei; Ramezani, Hamidreza; Wang, Yuan; Zhang, Xiang

    2016-03-01

    Parity-time (PT) symmetric systems experience phase transition between PT exact and broken phases at exceptional point. These PT phase transitions contribute significantly to the design of single mode lasers, coherent perfect absorbers, isolators, and diodes. However, such exceptional points are extremely difficult to access in practice because of the dispersive behaviour of most loss and gain materials required in PT symmetric systems. Here we introduce a method to systematically tame these exceptional points and control PT phases. Our experimental demonstration hinges on an active acoustic element that realizes a complex-valued potential and simultaneously controls the multiple interference in the structure. The manipulation of exceptional points offers new routes to broaden applications for PT symmetric physics in acoustics, optics, microwaves and electronics, which are essential for sensing, communication and imaging.

  11. Accessing the exceptional points of parity-time symmetric acoustics.

    PubMed

    Shi, Chengzhi; Dubois, Marc; Chen, Yun; Cheng, Lei; Ramezani, Hamidreza; Wang, Yuan; Zhang, Xiang

    2016-01-01

    Parity-time (PT) symmetric systems experience phase transition between PT exact and broken phases at exceptional point. These PT phase transitions contribute significantly to the design of single mode lasers, coherent perfect absorbers, isolators, and diodes. However, such exceptional points are extremely difficult to access in practice because of the dispersive behaviour of most loss and gain materials required in PT symmetric systems. Here we introduce a method to systematically tame these exceptional points and control PT phases. Our experimental demonstration hinges on an active acoustic element that realizes a complex-valued potential and simultaneously controls the multiple interference in the structure. The manipulation of exceptional points offers new routes to broaden applications for PT symmetric physics in acoustics, optics, microwaves and electronics, which are essential for sensing, communication and imaging. PMID:27025443

  12. Phase shift in the 24-hour rhythm of hippocampal EEG spiking activity in a rat model of temporal lobe epilepsy

    PubMed Central

    Stanley, David A.; Talathi, Sachin S.; Parekh, Mansi B.; Cordiner, Daniel J.; Zhou, Junli; Mareci, Thomas H.; Ditto, William L.

    2013-01-01

    For over a century epileptic seizures have been known to cluster at specific times of the day. Recent studies have suggested that the circadian regulatory system may become permanently altered in epilepsy, but little is known about how this affects neural activity and the daily pattern of seizures. To investigate, we tracked long-term changes in the rate of spontaneous hippocampal EEG spikes (SPKs) in a rat model of temporal lobe epilepsy. In healthy animals, SPKs oscillated with near 24-h period; however, after injury by status epilepticus, a persistent phase shift of ∼12 h emerged in animals that later went on to develop chronic spontaneous seizures. Additional measurements showed that global 24-h rhythms, including core body temperature and theta state transitions, did not phase shift. Instead, we hypothesized that locally impaired circadian input to the hippocampus might be responsible for the SPK phase shift. This was investigated with a biophysical computer model in which we showed that subtle changes in the relative strengths of circadian input could produce a phase shift in hippocampal neural activity. MRI provided evidence that the medial septum, a putative circadian relay center for the hippocampus, exhibits signs of damage and therefore could contribute to local circadian impairment. Our results suggest that balanced circadian input is critical to maintaining natural circadian phase in the hippocampus and that damage to circadian relay centers, such as the medial septum, may disrupt this balance. We conclude by discussing how abnormal circadian regulation may contribute to the daily rhythms of epileptic seizures and related cognitive dysfunction. PMID:23678009

  13. [A validation of the data obtained with the simultaneous recording of blood pressure and the 24-hour electrocardiogram].

    PubMed

    Germanò, G; Caparra, A; Valentino, S; Coia, F; Federico, L; Santucci, A

    1993-06-01

    Aim of this study was to evaluate the blood pressure (BP) measurement reliability of a light weight ambulatory BP and ECG recorder. Micro AM is a new 300 g portable apparatus that combines in one device both the ambulatory BP and solid state ECG recording. The dimensions of the Micro AM are 75 x 140 x 29 mm. The monitor measures BP using Korotkoff phase 1 for systolic and phase 5 for diastolic BP, and concurrently measures oscillometric BP, one method validating the other. In addition, the manual and programmed BP measurement modes can be supplemented by an "intelligent" mode in which the ECG triggers an ambulatory BP reading during an abnormal ST segment change. A standard mercury manometer was connected with the cuff of the Micro AM with a Y-shaped part, and 12 BP measurements were simultaneously taken at 5 min intervals by the automatic device in auscultatory mode and by a trained technician in 86 normotensive volunteers (aged from 18 to 44 years, 37 males and 49 females). The algebraic differences, the frequency distribution and the difference distribution of systolic and diastolic data between the 2 methods were calculated. The results show that the automatic method gives values for systolic BP that are lower than conventional ones (average differences -0.643 mmHg), whereas for diastolic BP, the values are higher (average differences +0.229 mmHg). Then, Student's paired t-test was used to evaluate statistically significant differences. The test relative to systolic BP was significant to the critical level of 0.1%, but the differences being 3 times smaller than the instrumental tolerance. On the contrary, diastolic BP differences were non significant. In conclusion, we found a good agreement between BP recorded automatically and by sphygmomanometer. PMID:8402748

  14. Successful Non-Surgical Deep Uterine Transfer of Porcine Morulae after 24 Hour Culture in a Chemically Defined Medium

    PubMed Central

    Martinez, Emilio A.; Angel, Miguel Angel; Cuello, Cristina; Sanchez-Osorio, Jonatan; Gomis, Jesus; Parrilla, Inmaculada; Vila, Jordi; Colina, Ignaci; Diaz, Marta; Reixach, Josep; Vazquez, Jose Luis; Vazquez, Juan Maria; Roca, Jordi; Gil, Maria Antonia

    2014-01-01

    Excellent fertility and prolificacy have been reported after non-surgical deep uterine transfers of fresh in vivo-derived porcine embryos. Unfortunately, when this technology is used with vitrified embryos, the reproductive performance of recipients is low. For this reason and because the embryos must be stored until they are transferred to the recipient farms, we evaluated the potential application of non-surgical deep uterine transfers with in vivo-derived morulae cultured for 24 h in liquid stage. In Experiment 1, two temperatures (25°C and 37°C) and two media (one fully defined and one semi-defined) were assessed. Morulae cultured in culture medium supplemented with bovine serum albumin and fetal calf serum at 38.5°C in 5% CO2 in air were used as controls. Irrespective of medium, the embryo viability after 24 h of culture was negatively affected (P<0.05) at 25°C but not at 37°C compared with the controls. Embryo development was delayed in all experimental groups compared with the control group (P<0.001). Most of the embryos (95.7%) cultured at 37°C achieved the full or expanded blastocyst stage, and unlike the controls, none of them hatched at the end of culture. In Experiment 2, 785 morulae were cultured in the defined medium at 37°C for 24 h, and the resulting blastocysts were transferred to the recipients (n = 24). Uncultured embryos collected at the blastocyst stage (n = 750) were directly transferred to the recipients and used as controls (n = 25). No differences in farrowing rates (91.7% and 92.0%) or litter sizes (9.0±0.6 and 9.4±0.8) were observed between the groups. This study demonstrated, for the first time, that high reproductive performance can be achieved after non-surgical deep uterine transfers with short-term cultured morulae in a defined medium, which opens new possibilities for the sanitary, safe national and international trade of porcine embryos and the commercial use of embryo transfer in pigs. PMID:25118944

  15. Time scale for point-defect equilibration in nanostructures

    SciTech Connect

    Millett, Paul C.; Wolf, Dieter; Desai, Tapan; Yamakov, Vesselin

    2008-10-20

    Molecular dynamics simulations of high-temperature annealing are performed on nanostructured materials enabling direct observation of vacancy emission from planar defects (i.e., grain boundaries and free surfaces) to populate the initially vacancy-free grain interiors on a subnanosecond time scale. We demonstrate a universal time-length scale correlation that governs these re-equilibration processes, suggesting that nanostructures are particularly stable against perturbations in their point-defect concentrations, caused for example by particle irradiation or temperature fluctuations.

  16. Electronic Dietary Intake Assessment (e-DIA): Comparison of a Mobile Phone Digital Entry App for Dietary Data Collection With 24-Hour Dietary Recalls

    PubMed Central

    O'Connor, Sarah; Giannelli, Valentina; Yap, Megan LH; Tang, Lie Ming; Roy, Rajshri; Louie, Jimmy Chun Yu; Hebden, Lana; Kay, Judy; Allman-Farinelli, Margaret

    2015-01-01

    Background The electronic Dietary Intake Assessment (e-DIA), a digital entry food record mobile phone app, was developed to measure energy and nutrient intake prospectively. This can be used in monitoring population intakes or intervention studies in young adults. Objective The objective was to assess the relative validity of e-DIA as a dietary assessment tool for energy and nutrient intakes using the 24-hour dietary recall as a reference method. Methods University students aged 19 to 24 years recorded their food and drink intake on the e-DIA for five days consecutively and completed 24-hour dietary recalls on three random days during this 5-day study period. Mean differences in energy, macro-, and micronutrient intakes were evaluated between the methods using paired t tests or Wilcoxon signed-rank tests, and correlation coefficients were calculated on unadjusted, energy-adjusted, and deattenuated values. Bland-Altman plots and cross-classification into quartiles were used to assess agreement between the two methods. Results Eighty participants completed the study (38% male). No significant differences were found between the two methods for mean intakes of energy or nutrients. Deattenuated correlation coefficients ranged from 0.55 to 0.79 (mean 0.68). Bland-Altman plots showed wide limits of agreement between the methods but without obvious bias. Cross-classification into same or adjacent quartiles ranged from 75% to 93% (mean 85%). Conclusions The e-DIA shows potential as a dietary intake assessment tool at a group level with good ranking agreement for energy and all nutrients. PMID:26508282

  17. Demand and characteristics of a psychiatric 24-hour emergency service performed by mandatory rotation of licensed psychiatrists in Swiss primary care

    PubMed Central

    Chmiel, Corinne; Rosemann, Thomas; Senn, Oliver

    2014-01-01

    Background To investigate characteristics of and satisfaction with psychiatric 24-hour emergency primary care performed by mandatory rotation of licensed psychiatrists as a viable baseline for possible reorganizational measures. Methods This was a questionnaire-based cross-sectional study (November 2010–April 2011). The number of patient–psychiatrist encounters, modes of contact, and patient and psychiatrist characteristics were assessed. Diagnoses were coded with ICD-10 (International Classification of Diseases, version 10). Results From 167 duty episodes, 74 (44%) were recorded. Of the psychiatrists (n=44), 52% were female, and mean age (standard deviation) was 49.9 (5.2) years. The median number of encounters per episode was 4 (interquartile range 0–8), mainly in the evenings. Demand for “face-to-face” (direct) patient visits was significantly more common (64.0%) than practice (1.3%) or telephone consultations (34.7%). In 83.8%, psychiatrists judged the encounter as adequate at the patient’s location. A total of 43 different diagnoses were recorded: mainly schizophrenic disorders (23.9%), suicidal behavior (15.2%), and acute stress reactions (10.3%). Psychiatrists felt burdened by services (62.5%): in 39.2%, they felt threatened; and in 6.8%, violence occurred. In 32.4%, bills were not paid for. If services were optional, 45.2% would participate. Conclusion Our findings indicate justified demand for direct mobile patient visits, suggesting that emergency care should be multifaceted, and sole provision of psychiatric care at stationed emergency facilities may not always be appropriate. Reorganization of 24-hour emergency services should carefully evaluate patient and provider’s needs before changing established structures. PMID:24707172

  18. Correlation of Occupational Stress Index with 24-hour Urine Cortisol and Serum DHEA Sulfate among City Bus Drivers: A Cross-sectional Study

    PubMed Central

    Lin, Mia Chihya; Lu, Luo; Tai, John Jen

    2011-01-01

    Objectives The questionnaire of occupational stress index (OSI) has been popular in the workplace, and it has been tailored for bus drivers in Taiwan. Nevertheless, its outcomes for participants are based on self-evaluations, thus validation by their physiological stress biomarker is warranted and this is the main goal of this study. Methods A cross-sectional study of sixty-three city bus drivers and fifty-four supporting staffs for comparison was conducted. Questionnaire surveys, 24-hour urine cortisol testing, and blood draws for dehydroepiandrosterone-sulfate (DHEA-S) testing were performed. The measured concentrations of these biological measures were logarithmically transformed before the statistical analysis where various scores of stressor factors, moderators, and stress effects of each OSI domain were analyzed by applying multiple linear regression models. Results For drivers, the elevated 24-hour urine cortisol level was associated with a worker's relationship with their supervisor and any life change events in the most recent 3 months. The DHEA-S level was higher in drivers of younger age as well as drivers with more concerns relating to their salary and bonuses. Non-drivers showed no association between any stressor or satisfaction and urine cortisol and blood DHEA-S levels. Conclusion Measurements of biomarkers may offer additional stress evaluations with OSI questionnaires for bus drivers. Increased DHEA-S and cortisol levels may result from stressors like income security. Prevention efforts towards occupational stress and life events and health promotional efforts for aged driver were important anti-stress remedies. PMID:22953199

  19. Validation of the BPLab® 24-hour blood pressure monitoring system in a pediatric population according to the 1993 British Hypertension Society protocol

    PubMed Central

    Ledyaev, Mikhail Y; Stepanova, Olga V; Ledyaeva, Anastasia M

    2015-01-01

    Background Automatic 24-hour ambulatory blood pressure (BP) monitoring (ABPM) is a basic procedure performed in adults with arterial hypertension, but ABPM monitors have become widely used in pediatric practice only recently. The main problem is the lack of common normative data sets for ABPM in children and the small number of appropriate monitors that can be used for analysis of the 24-hour BP profile in this age group. The aim of this study was to validate the BPLab® ABPM monitor according to the 1993 British Hypertension Society (BHS-93) protocol, as well as to work out solutions regarding the feasibility of this device in pediatric practice. Methods Our study included 30 children of both sexes and aged 5–15 years, ie, “older” children according to the BHS-93 protocol. Before starting the study, we obtained ethical approval from the regional scientific ethics committee. All participants and their parents signed their written consent for participation in the study. The data were simultaneously obtained by three experts, who had completed a noninvasive BP measurement training course. BP values were measured using the Korotkoff auscultatory method (Phase I for systolic BP and Phase V for diastolic BP). Discrepancies in the systolic and diastolic BP measurements (n=180; 90 for each expert) were analyzed according to the criteria specified in the BHS-93 protocol. Results The device was graded “A” for both systolic BP and diastolic BP according to the criteria of the BHS-93 protocol. Conclusion The BPLab ABPM device may be recommended for extensive pediatric use. PMID:25674018

  20. Parity-time symmetry broken by point-group symmetry

    SciTech Connect

    Fernández, Francisco M. Garcia, Javier

    2014-04-15

    We discuss a parity-time (PT) symmetric Hamiltonian with complex eigenvalues. It is based on the dimensionless Schrödinger equation for a particle in a square box with the PT-symmetric potential V(x, y) = iaxy. Perturbation theory clearly shows that some of the eigenvalues are complex for sufficiently small values of |a|. Point-group symmetry proves useful to guess if some of the eigenvalues may already be complex for all values of the coupling constant. We confirm those conclusions by means of an accurate numerical calculation based on the diagonalization method. On the other hand, the Schrödinger equation with the potential V(x, y) = iaxy{sup 2} exhibits real eigenvalues for sufficiently small values of |a|. Point group symmetry suggests that PT-symmetry may be broken in the former case and unbroken in the latter one.

  1. Metabolic Engineering of Light and Dark Biochemical Pathways in Wild-Type and Mutant Strains of Synechocystis PCC 6803 for Maximal, 24-Hour Production of Hydrogen Gas

    SciTech Connect

    Ely, Roger L.; Chaplen, Frank W.R.

    2014-03-11

    This project used the cyanobacterial species Synechocystis PCC 6803 to pursue two lines of inquiry, with each line addressing one of the two main factors affecting hydrogen (H2) production in Synechocystis PCC 6803: NADPH availability and O2 sensitivity. H2 production in Synechocystis PCC 6803 requires a very high NADPH:NADP+ ratio, that is, the NADP pool must be highly reduced, which can be problematic because several metabolic pathways potentially can act to raise or lower NADPH levels. Also, though the [NiFe]-hydrogenase in PCC 6803 is constitutively expressed, it is reversibly inactivated at very low O2 concentrations. Largely because of this O2 sensitivity and the requirement for high NADPH levels, a major portion of overall H2 production occurs under anoxic conditions in the dark, supported by breakdown of glycogen or other organic substrates accumulated during photosynthesis. Also, other factors, such as N or S limitation, pH changes, presence of other substances, or deletion of particular respiratory components, can affect light or dark H2 production. Therefore, in the first line of inquiry, under a number of culture conditions with wild type (WT) Synechocystis PCC 6803 cells and a mutant with impaired type I NADPH-dehydrogenase (NDH-1) function, we used H2 production profiling and metabolic flux analysis, with and without specific inhibitors, to examine systematically the pathways involved in light and dark H2 production. Results from this work provided rational bases for metabolic engineering to maximize photobiological H2 production on a 24-hour basis. In the second line of inquiry, we used site-directed mutagenesis to create mutants with hydrogenase enzymes exhibiting greater O2 tolerance. The research addressed the following four tasks: 1. Evaluate the effects of various culture conditions (N, S, or P limitation; light/dark; pH; exogenous organic carbon) on H2 production profiles of WT cells and an NDH-1 mutant; 2. Conduct metabolic flux analyses for

  2. Local troposphere augmentation for real-time precise point positioning

    NASA Astrophysics Data System (ADS)

    Shi, Junbo; Xu, Chaoqian; Guo, Jiming; Gao, Yang

    2014-12-01

    The IGS real-time service (RTS) enables real-time precise point positioning (PPP) at a global scale. A long convergence time however is still a challenging factor. In order to reduce the convergence time, external troposphere corrections could be introduced to remove the troposphere effects on the coordinate solution. This paper proposes the use of a local troposphere model to augment real-time PPP. First, undifferenced observations from a network of multiple stations are processed to estimate the station-based troposphere zenith wet delay (ZWD). A set of local troposphere fitting coefficients are then derived using a proposed optimal fitting model. Finally, the determined troposphere fitting coefficients are broadcast to users to reduce the convergence time in the user solution. A continuous operating reference station (CORS) network is utilized to assess the performance of the proposed approach under quiet and active troposphere conditions. The numerical results show that the overall fitting precisions of the local troposphere model can reach 1.42 and 1.05 cm under the two troposphere conditions. The convergence time of the positioning solutions, especially the height solution, can be greatly reduced using the local troposphere model. The horizontal accuracy of 9.2 cm and the vertical accuracy of 10.1 cm are obtainable under the quiet troposphere condition after 20 min of initialization time, compared to the 14.7 cm horizontal and 21.5 cm vertical accuracies in the conventional troposphere estimation approach. Moreover, the horizontal accuracies of 13.0 cm and the vertical accuracies of 12.4 cm have also been obtained after 20 min under the active troposphere condition.

  3. The timing of control signals underlying fast point-to-point arm movements.

    PubMed

    Ghafouri, M; Feldman, A G

    2001-04-01

    It is known that proprioceptive feedback induces muscle activation when the facilitation of appropriate motoneurons exceeds their threshold. In the suprathreshold range, the muscle-reflex system produces torques depending on the position and velocity of the joint segment(s) that the muscle spans. The static component of the torque-position relationship is referred to as the invariant characteristic (IC). According to the equilibrium-point (EP) hypothesis, control systems produce movements by changing the activation thresholds and thus shifting the IC of the appropriate muscles in joint space. This control process upsets the balance between muscle and external torques at the initial limb configuration and, to regain the balance, the limb is forced to establish a new configuration or, if the movement is prevented, a new level of static torques. Taken together, the joint angles and the muscle torques generated at an equilibrium configuration define a single variable called the EP. Thus by shifting the IC, control systems reset the EP. Muscle activation and movement emerge following the EP resetting because of the natural physical tendency of the system to reach equilibrium. Empirical and simulation studies support the notion that the control IC shifts and the resulting EP shifts underlying fast point-to-point arm movements are gradual rather than step-like. However, controversies exist about the duration of these shifts. Some studies suggest that the IC shifts cease with the movement offset. Other studies propose that the IC shifts end early in comparison to the movement duration (approximately, at peak velocity). The purpose of this study was to evaluate the duration of the IC shifts underlying fast point-to-point arm movements. Subjects made fast (hand peak velocity about 1.3 m/s) planar arm movements toward different targets while grasping a handle. Hand forces applied to the handle and shoulder/elbow torques were, respectively, measured from a force sensor placed

  4. Single time point isothermal drug stability experiments at constant humidity.

    PubMed

    Tao, Jian-Lin; Zhan, Xian-Cheng; Li, Lin-Li; Lin, Bing; Jiang, Lu

    2009-03-01

    A single time point isothermal drug stability experiments at constant humidity is introduced. In the new method, kinetic parameters related to both moisture and temperature were obtained by a single pair of experiments: these related to moisture by one with a group of testing humidities and a fixed temperature, those related to temperature by the other with a group of testing temperatures and a constant humidity. By a simulation, the estimates for the kinetic parameters (E(a), m, A) obtained by the proposed method and the reported programmed humidifying and heating method were statistically evaluated and were compared with those obtained by the isothermal measurements at constant humidity. Results indicated that under the same experimental conditions, the estimates obtained by the proposed method were significantly more precise than those obtained by the reported programmed humidifying and heating method. The estimates obtained by the isothermal method at constant humidity were somewhat more precise than those obtained by the proposed method. However, the experimental period needed by the isothermal method at constant humidity was greatly longer than that needed by the proposed method. The stability of dicloxacillin sodium, as a solid state model, was investigated by the single time point isothermal drug stability experiments at constant humidity. The results indicated that the kinetic parameters obtained by the proposed method were comparable to those from the reported. PMID:19252391

  5. Control of bleeding by silk ligation and diathermy coagulation during tonsillectomy: A comparison of efficacy of the two techniques in the first 24 hours after surgery

    PubMed Central

    Anwar, Khurshid; Ahmad, Rafiq; Khan, Muneeb

    2015-01-01

    Objective: To assess and compare the relative efficacy of silk ligation and diathermy coagulation techniques in controlling bleeding during tonsillectomy in the first 24 hours. Methods: This prospective study was conducted at the Department of ENT, Khalifa Gul Nawaz Teaching Hospital, Bannu and this department related consultants’ private clinics from January 1, 2012 to December 31, 2014. The study included 180 cases. All patients included were having history of recurrent, acute tonsillitis, with more than 6–7 episodes in one year, five episodes per year for two years, or three episodes per year for three years. All the surgeries were performed by dissection method. Haemostasis during the procedure was secured by either ligation with silk 1 or using diathermy. The results were analyzed using SPSS 16.0 for windows. Results: A total of180 cases were included in the study. The ages of the patients ranged from 5 to 40 years with the mean age of 15.56 years and a std.deviation of +/- 8.24. The male to female ratio was 1.25:1. The number of hemorrhages occurring was greater in the ‘diathermy coagulation’ group as compared to the ‘silk ligation’ group. However, the observed difference was statistically insignificant (p >.05). Conclusion: Primary haemorrhage occurring during tonsillectomy is a serious threat and control of bleeding during the procedure should therefore be meticulous. Both suture ligation and coagulation diathermy for control of bleeders during the procedure by dissection method are equally effective. PMID:26430438

  6. Tele-ECG and 24-hour physician support over telephone for rural doctors can help early treatment of acute myocardial infarction in rural areas.

    PubMed

    Vivek, Chauhan; Vikrant, Kanwar

    2016-04-01

    We observed that many patients of acute myocardial infarction (AMI) were reaching our hospital out of the 12 hour window period for thrombolysis. This led to poor patient outcomes. There were multiple reasons for the delay, prominent among them was lack of diagnostic facilities in the rural health care centers. We therefore planned a Tele-Electrocardiography (Tele-ECG) based pilot project in Kangra District of Himachal Pradesh in India, which was funded by the Indian Council of Medical Research. The intention was to reduce the pre-hospital delay in AMI by enabling the rural doctors of Kangra using Tele-ECG facility and a 24-hour physician support to manage patients of AMI. We did a baseline knowledge, attitude, and practice (KAP) assessment study of the doctors in our intervention centers to understand their needs. The data obtained through the KAP study was an eye opener for us and justifies the need for a Tele-ECG facility for rural doctors in India. PMID:26187625

  7. Intersalt: an international study of electrolyte excretion and blood pressure. Results for 24 hour urinary sodium and potassium excretion. Intersalt Cooperative Research Group.

    PubMed Central

    1988-01-01

    The relations between 24 hour urinary electrolyte excretion and blood pressure were studied in 10,079 men and women aged 20-59 sampled from 52 centres around the world based on a highly standardised protocol with central training of observers, a central laboratory, and extensive quality control. Relations between electrolyte excretion and blood pressure were studied in individual subjects within each centre and the results of these regression analyses pooled for all 52 centres. Relations between population median electrolyte values and population blood pressure values were also analysed across the 52 centres. Sodium excretion ranged from 0.2 mmol/24 h (Yanomamo Indians, Brazil) to 242 mmol/24 h (north China). In individual subjects (within centres) it was significantly related to blood pressure. Four centres found very low sodium excretion, low blood pressure, and little or no upward slope of blood pressure with age. Across the other 48 centres sodium was significantly related to the slope of blood pressure with age but not to median blood pressure or prevalence of high blood pressure. Potassium excretion was negatively correlated with blood pressure in individual subjects after adjustment for confounding variables. Across centres there was no consistent association. The relation of sodium to potassium ratio to blood pressure followed a pattern similar to that of sodium. Body mass index and heavy alcohol intake had strong, significant independent relations with blood pressure in individual subjects. PMID:3416162

  8. Computer simulation of the effect of dDAVP with saline loading on fluid balance after 24-hour head-down tilt

    NASA Technical Reports Server (NTRS)

    Srinivasan, R. S.; Simanonok, K. E.; Charles, J. B.

    1994-01-01

    Fluid loading (FL) before Shuttle reentry is a countermeasure currently in use by NASA to improve the orthostatic tolerance of astronauts during reentry and postflight. The fluid load consists of water and salt tablets equivalent to 32 oz (946 ml) of isotonic saline. However, the effectiveness of this countermeasure has been observed to decrease with the duration of spaceflight. The countermeasure's effectiveness may be improved by enhancing fluid retention using analogs of vasopressin such as lypressin (LVP) and desmopressin (dDAVP). In a computer simulation study reported previously, we attempted to assess the improvement in fluid retention obtained by the use of LVP administered before FL. The present study is concerned with the use of dDAVP. In a recent 24-hour, 6 degree head-down tilt (HDT) study involving seven men, dDAVP was found to improve orthostatic tolerance as assessed by both lower body negative pressure (LBNP) and stand tests. The treatment restored Luft's cumulative stress index (cumulative product of magnitude and duration of LBNP) to nearly pre-bedrest level. The heart rate was lower and stroke volume was marginally higher at the same LBNP levels with administration of dDAVP compared to placebo. Lower heart rates were also observed with dDAVP during stand test, despite the lower level of cardiovascular stress. These improvements were seen with only a small but significant increase in plasma volume of approximately 3 percent. This paper presents a computer simulation analysis of some of the results of this HDT study.

  9. Taming the Exceptional Points of Parity-Time Symmetric Acoustics

    NASA Astrophysics Data System (ADS)

    Dubois, Marc; Shi, Chengzhi; Chen, Yun; Cheng, Lei; Ramezani, Hamidreza; Wang, Yuan; Zhang, Xiang

    Parity-time (PT) symmetric concept and development lead to a wide range of applications including coherent perfect absorbers, single mode lasers, unidirectional cloaking and sensing, and optical isolators. These new applications and devices emerge from the existence of a phase transition in PT symmetric complex-valued potential obtained by balancing gain and loss materials. However, the systematic extension of such devices is adjourned by the key challenge in the management of the complex scattering process within the structure in order to engineer PT phase and exceptional points. Here, based on active acoustic elements, we experimentally demonstrate the simultaneous control of complex-valued potentials and multiple interference inside the structure at any given frequency. This method broadens the scope of applications for PT symmetric devices in many fields including optics, microwaves, electronics, which are crucial for sensing, imaging, cloaking, lasing, absorbing, etc.

  10. Nonparametric directionality measures for time series and point process data.

    PubMed

    Halliday, David M

    2015-06-01

    The need to determine the directionality of interactions between neural signals is a key requirement for analysis of multichannel recordings. Approaches most commonly used are parametric, typically relying on autoregressive models. A number of concerns have been expressed regarding parametric approaches, thus there is a need to consider alternatives. We present an alternative nonparametric approach for construction of directionality measures for bivariate random processes. The method combines time and frequency domain representations of bivariate data to decompose the correlation by direction. Our framework generates two sets of complementary measures, a set of scalar measures, which decompose the total product moment correlation coefficient summatively into three terms by direction and a set of functions which decompose the coherence summatively at each frequency into three terms by direction: forward direction, reverse direction and instantaneous interaction. It can be undertaken as an addition to a standard bivariate spectral and coherence analysis, and applied to either time series or point-process (spike train) data or mixtures of the two (hybrid data). In this paper, we demonstrate application to spike train data using simulated cortical neurone networks and application to experimental data from isolated muscle spindle sensory endings subject to random efferent stimulation. PMID:25958923

  11. "2001: A Space Odyssey" Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    2001-01-01

    The prospects for "24 hour" commuter flights to the Moon. similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale. are examined using two near term. "high leverage" technologies-liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Iron-rich volcanic glass. or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow. has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat-essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller. more affordable. easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  12. "2001: A Space Odyssey" Revisited--The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; Dudzinski, Leonard A.

    1998-01-01

    The prospects for "24 hour" commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, "high leverage" technologies--liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and "lunar-derived" oxygen (LUNOX) production. Ironrich volcanic glass, or "orange soil," discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4% oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way, LANTR utilizes the large divergent section of its nozzle as an "afterburner" into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging front the engine's choked sonic throat--essentially "scramjet propulsion in reverse." By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that "big engine" performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low-density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or "in-line" Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an "expendable mode" initially, to maximize delivered surface payload on each mission. The increased

  13. 2001: A Space Odyssey Revisited: The Feasibility of 24 Hour Commuter Flights to the Moon Using NTR Propulsion with LUNOX Afterburners. Revised

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley; Dudzinski, Leonard A.

    2003-01-01

    The prospects for 24 hour commuter flights to the Moon, similar to that portrayed in 2001: A Space Odyssey but on a more Spartan scale, are examined using two near term, high leverage technologies: liquid oxygen (LOX)-augmented nuclear thermal rocket (NTR) propulsion and lunar-derived oxygen (LUNOX) production. Iron-rich volcanic glass, or orange soil, discovered during the Apollo 17 mission to Taurus-Littrow, has produced a 4 percent oxygen yield in recent NASA experiments using hydrogen reduction. LUNOX development and utilization would eliminate the need to transport oxygen supplies from Earth and is expected to dramatically reduce the size, cost and complexity of space transportation systems. The LOX-augmented NTR concept (LANTR) exploits the high performance capability of the conventional liquid hydrogen (LH2)-cooled NTR and the mission leverage provided by LUNOX in a unique way. LANTR utilizes the large divergent section of its nozzle as an afterburner into which oxygen is injected and supersonically combusted with nuclear preheated hydrogen emerging from the engine's choked sonic throat, essentially scramjet propulsion in reverse. By varying the oxygen-to-hydrogen mixture ratio, the LANTR engine can operate over a wide range of thrust and specific impulse (Isp) values while the reactor core power level remains relatively constant. The thrust augmentation feature of LANTR means that big engine performance can be obtained using smaller, more affordable, easier to test NTR engines. The use of high-density LOX in place of low density LH2 also reduces hydrogen mass and tank volume resulting in smaller space vehicles. An implementation strategy and evolutionary lunar mission architecture is outlined which requires only Shuttle C or in-line Shuttle-derived launch vehicles, and utilizes conventional NTR-powered lunar transfer vehicles (LTVs), operating in an expendable mode initially, to maximize delivered surface payload on each mission. The increased payload is

  14. Time trend and change point of reference evapotranspiration over Iran

    NASA Astrophysics Data System (ADS)

    Hosseinzadeh Talaee, P.; Shifteh Some'e, B.; Sobhan Ardakani, S.

    2014-05-01

    Identifying changes in reference evapotranspiration (ETo) can help in future planning of crop water requirements and water resources for high water-use efficiency. This study analyzes the ETo trends on a seasonal and annual timescale by applying various statistical tools to data from 41 Iranian weather stations during the period between 1966 and 2005. The Mann-Kendall test after removal of significant serial correlation was used to determine the statistical significance of the trends, and the change point in the ETo time series was determined using the cumulative sum technique. The results showed that (1) the significant increasing trends of annual ETo were observed at seven stations which are located in different parts of Iran, (2) the stations located at the southeast, northeast, and northwest corners of Iran experienced the highest positive change of annual ETo, and (3) the changes in seasonal ETo were most pronounced in the winter season, both in terms of trend magnitude and the number of stations with significant trends.

  15. The assessment of schizotypal features over two points in time.

    PubMed

    Squires-Wheeler, E; Skodol, A E; Erlenmeyer-Kimling, L

    1991-12-01

    The expression of schizotypal personality traits was assessed in mid-adolescence and again in young adulthood for three groups of offspring defined by the psychiatric diagnosis of their parents. Parental diagnoses included schizophrenic disorder (47 offspring), affective disorder (39 offspring), and 'no psychiatric disorder', or normal controls (82 offspring). Initially, schizotypal traits were assessed from video-taped semi-structured psychiatric interviews, subsequently rated by trained psychiatrists blind to the parental psychiatric status of the subjects, and/or direct clinical interviews (Schedule for Affective Disorders-Lifetime Version (SADS-L)). The second assessment was conducted by trained social workers and psychologists by means of a semi-structured interview specifically for DSM-III-R personality disorders (Personality Disorder Examination) and sections of the SDS-L where indicated. These interviewers were blind to the parental status and to previous psychiatric assessments of the offspring. The rates of stability of features or the rates of progression to axis I psychotic disorders (Schizophrenia, Schizoaffective Disorder, and Unspecified Functional Psychosis) were evaluated. Concordance of assessments over time is reported as a function of threshold for expression of traits at initial evaluation, i.e., two or more, three or more, or four or more features present. Concordance increases as the threshold for expression increases, as expected. The effect of comorbid clinical status, e.g., the coexistence of schizotypal traits and anxiety and/or depressive features on the concordance pattern, is also examined by parental diagnostic group status. The offspring of affective disorder parents exhibited higher rates of anxiety and/or depressive features at both points in time, exhibited higher concordance for anxiety and/or depressive features, and exhibited higher rates of 'transformation' of initial schizotypal features to anxiety and/or depressive features

  16. The drug efficacy and adverse reactions in a mouse model of oral squamous cell carcinoma treated with oxaliplatin at different time points during a day

    PubMed Central

    Yang, Kai; Zhao, Ningbo; Zhao, Dan; Chen, Dan; Li, Yadong

    2013-01-01

    Background Recent studies have shown that the growth and proliferation of cancer cells in vivo exhibit circadian rhythm, and the efficacy and adverse reactions of platinum-based anticancer drugs administered at different times of the day vary significantly on colon cancer. However, since the circadian rhythms of growth and proliferation of various cancer cells often differ, the question of whether the administration of platinum anticancer drugs at different times of the day exerts significantly different efficacy and adverse effects on oral cancers remains to be elucidated. This study has compared the efficacy and adverse effects of oxaliplatin (L-OHP) administration at different times during a day on oral squamous cell carcinoma in mice and has analyzed cellular circadian rhythms. Methods The mouse model for oral squamous cell carcinoma was established in 75 nude mice, housed in a 12 hour light/12 hour dark cycle environment. The mice were randomly divided into five groups; four experimental groups were intravenously injected with L-OHP at four time points within a 24-hour period (4, 10, 16, and 22 hours after lights on [HALO]). The control group was intravenously injected with the same volume of saline. Treatment efficacy and adverse reactions were compared on the seventh day after the injection, at 22 HALO. The existence of circadian rhythms was determined by cosine analysis. Results Only injections of L-OHP at 16 and 22 HALO significantly prolonged animal survival time. The adverse reactions in mice injected with L-OHP at 16 and 22 HALO were significantly less than those observed in mice administered L-OHP at 4 and 10 HALO. The cosine fitting curve showed that the survival time and adverse reactions exhibited circadian rhythm. Conclusion The time factor should be considered when treating patients with oral squamous cell carcinoma with L-OHP in order to achieve better efficacy, reduce the adverse reactions, and improve the patients’ survival time and quality

  17. Sex and age-related differences in performance in a 24-hour ultra-cycling draft-legal event – a cross-sectional data analysis

    PubMed Central

    2014-01-01

    Background The purpose of this study was to examine the sex and age-related differences in performance in a draft-legal ultra-cycling event. Methods Age-related changes in performance across years were investigated in the 24-hour draft-legal cycling event held in Schötz, Switzerland, between 2000 and 2011 using multi-level regression analyses including age, repeated participation and environmental temperatures as co-variables. Results For all finishers, the age of peak cycling performance decreased significantly (β = −0.273, p = 0.036) from 38 ± 10 to 35 ± 6 years in females but remained unchanged (β = −0.035, p = 0.906) at 41.0 ± 10.3 years in males. For the annual fastest females and males, the age of peak cycling performance remained unchanged at 37.3 ± 8.5 and 38.3 ± 5.4 years, respectively. For all female and male finishers, males improved significantly (β = 7.010, p = 0.006) the cycling distance from 497.8 ± 219.6 km to 546.7 ± 205.0 km whereas females (β = −0.085, p = 0.987) showed an unchanged performance of 593.7 ± 132.3 km. The mean cycling distance achieved by the male winners of 960.5 ± 51.9 km was significantly (p < 0.001) greater than the distance covered by the female winners with 769.7 ± 65.7 km but was not different between the sexes (p > 0.05). The sex difference in performance for the annual winners of 19.7 ± 7.8% remained unchanged across years (p > 0.05). The achieved cycling distance decreased in a curvilinear manner with advancing age. There was a significant age effect (F = 28.4, p < 0.0001) for cycling performance where the fastest cyclists were in age group 35–39 years. Conclusion In this 24-h cycling draft-legal event, performance in females remained unchanged while their age of peak cycling performance decreased and performance in males improved while their age of peak cycling performance remained unchanged. The annual fastest females and males were 37.3 ± 8.5 and 38.3 ± 5.4 years old, respectively. The sex

  18. Time's Arrow and Archimedes' Point - New Directions for the Physics of Time

    NASA Astrophysics Data System (ADS)

    Price, Huw

    1997-12-01

    Why is the future so different from the past? Why does the past affect the future and not the other way around? What does quantum mechanics really tell us about the world? In this important and accessible book, Huw Price throws fascinating new light these great mysteries of modern physics, and connects them in a wholly original way. Price begins with the mystery of the arrow of time. Price shows that, for over a century, most physicists have thought about problems of time in the wrong way. Misled by the human perspective from within time, which distorts and exaggerates the differences between past and future, they have fallen victim to what Price calls the "double standard fallacy": proposed explanations of the difference between the past and the future turn out to rely on a difference which has been slipped in at the beginning, when the physicists themselves treat the past and future in different ways. To avoid this fallacy, Price argues, we need to overcome our natural tendency to think about the past and the future differently. We need to imagine a point outside time--an Archimedean "view from nowhen"--from which to observe time in an unbiased way. Time's Arrow and Archimedes'Point presents an innovative and controversial view of time and contemporary physics. In this exciting book, Price urges physicists, philosophers, and anyone who has ever pondered the mysteries of time to look at the world from the fresh perspective of Archimedes' Point and gain a deeper understanding of ourselves, the universe around us, and our own place in time.

  19. Real time simulator with Ti floating point digital signal processor

    SciTech Connect

    Razazian, K.; Bobis, J.P.; Dieckman, S.L.; Raptis, A.C.

    1994-08-01

    This paper describes the design and operation of a Real Time Simulator using Texas Instruments TMS320C30 digital signal processor. This system operates with two banks of memory which provide the input data to digital signal processor chip. This feature enables the TMS320C30 to be utilized in variety of applications for which external connections to acquire input data is not needed. In addition, some practical applications of this Real Time Simulator are discussed.

  20. Thrombolysis in anterior versus posterior circulation strokes: timing of recanalization, ischemic tolerance, and other differences.

    PubMed

    Pagola, Jorge; Ribo, Marc; Alvarez-Sabin, José; Rubiera, Marta; Santamarina, Estevo; Maisterra, Olga; Delgado-Mederos, Raquel; Ortega, Gemma; Quintana, Manuel; Molina, Carlos A

    2011-04-01

    Previous studies have suggested a greater ischemic tolerance in posterior circulation as compared to anterior cerebral circulation. We aimed to investigate whether a differential response exists between anterior and posterior circulation strokes. Two hundred and four middle cerebral artery (MCA) patients and 28 basilar artery occlusion (BAO) patients treated with intravenous recombinant tissue plasminogen activator were included. Transcranial Doppler assessed recanalization at different time points. Patients were divided in three groups: total time of ischemia (TTI)<6, 6-24, or>24 hours. We calculated the percentage of recovery (admission National Institutes of Health Stroke Scale [NIHSS]- discharge NIHSS/admission NIHSS)×100. Mean time to treatment was longer in BAO patients (P=.031). Early recanalization was more frequent among MCA occlusions (41% vs 29%; P=.039); the rate of persisting occlusion at 24 hours was similar (P=.933). Clinical recovery according to TTI was similar in each group: <6 hours: BAO 84%/MCA 69%; 6-24 hours: BAO 63%/MCA 61%; >24 hours: BAO -44%/MCA 11% (P=.23). For each hour of ischemia MCA patients worsened 1.78% (P=.035) and BAO 1.76% (P=.421). MCA occlusions compared to BAO were independently associated with hemorrhagic transformation (OR: 8.2; P=.043). Our data do not support the theory of increased ischemic tolerance in posterior circulation. Despite longer time-to-treatment, BAO were more resistant to hemorrhagic transformations. PMID:20040010

  1. Circadian Melatonin and Temperature Taus in Delayed Sleep-wake Phase Disorder and Non-24-hour Sleep-wake Rhythm Disorder Patients: An Ultradian Constant Routine Study.

    PubMed

    Micic, Gorica; Lovato, Nicole; Gradisar, Michael; Burgess, Helen J; Ferguson, Sally A; Lack, Leon

    2016-08-01

    Our objectives were to investigate the period lengths (i.e., taus) of the endogenous core body temperature rhythm and melatonin rhythm in delayed sleep-wake phase disorder patients (DSWPD) and non-24-h sleep-wake rhythm disorder patients (N24SWD) compared with normally entrained individuals. Circadian rhythms were measured during an 80-h ultradian modified constant routine consisting of 80 ultrashort 1-h "days" in which participants had 20-min sleep opportunities alternating with 40 min of enforced wakefulness. We recruited a community-based sample of 26 DSWPD patients who met diagnostic criteria (17 males, 9 females; age, 21.85 ± 4.97 years) and 18 healthy controls (10 males, 8 females; age, 23.72 ± 5.10 years). Additionally, 4 full-sighted patients (3 males, 1 female; age, 25.75 ± 4.99 years) were diagnosed with N24SWD and included as a discrete study group. Ingestible core temperature capsules were used to record minute temperatures that were averaged to obtain 80 hourly data points. Salivary melatonin concentration was assessed every half-hour to determine time of dim light melatonin onset at the beginning and end of the 80-h protocol. DSWPD patients had significantly longer melatonin rhythm taus (24 h 34 min ± 17 min) than controls (24 h 22 min ± 15 min, p = 0.03, d = 0.70). These results were further supported by longer temperature rhythm taus in DSWPD patients (24 h 34 min ± 26 min) relative to controls (24 h 13 min ± 15 min, p = 0.01, d = 0.80). N24SWD patients had even longer melatonin (25 h ± 19 min) and temperature (24 h 52 min ± 17 min) taus than both DSWPD (p = 0.007, p = 0.06) and control participants (p < 0.001, p = 0.02, respectively). Between 12% and 19% of the variance in DSWPD patients' sleep timing could be explained by longer taus. This indicates that longer taus of circadian rhythms may contribute to the DSWPD patients' persistent tendency to delay, their frequent failure to respond to treatment, and their relapse following treatment

  2. [Time point and methods for emergency killing in cattle].

    PubMed

    Khol, J L; Schafbauer, T; Wittek, T

    2016-01-01

    Emergency killing is defined as the killing of injured or ill animals to avoid excessive pain or harm. Decision-making for emergency killing or a prolonged therapy can be difficult and has to be based on the case history and results of the clinical examination contributing to the prognosis, particularly in downer cows. Evaluation of enzyme activities and total bilirubin can be used as additional factors pointing to a guarded prognosis; however, none of these parameters provides a clear cut-off value indicating a poor prognosis and mandatory emergency killing. Euthanasia by intravenous drug application is seen as the least stressful method of killing and should therefore always be the first method of choice for emergency killing in cattle. Drugs containing pentobarbital as well as a combination of three different drugs (T61-Injektionslösung, MSD Animal Health) are available for euthanasia in cattle. All drugs must be administered by a veterinarian. Before application of pentobarbital, an animal should be deeply sedated. The administration of T61 requires anaesthesia of the animal and it is not licensed for use in pregnant animals. Alternative methods for emeragency killing, including captive bolt stunning and the use of firearms, although not regularly performed by veterinarians, should be assessed concerning their correct application and performance. When captive bolt stunning or emergency killing using firearms is performed, the correct position of the device is crucial as well as a quick exsanguination or the application of a pithing rod for the actual killing of the animal after captive bolt stunning. In addition to medical considerations, economic and personal factors contribute to the decision about emergency killing in cattle. Therefore, veterinarians should aim to evaluate each case thoroughly based on personal knowledge and experience, case history, clinical findings and laboratory parameters to avoid prolonged suffering of the animal. PMID:26830543

  3. Lunar Crater Rays Point to a New Lunar Time Scale

    NASA Astrophysics Data System (ADS)

    Martel, L. M. V.

    2004-09-01

    The Lunar Time Scale should be reevaluated -- suggest remote sensing studies of lunar crater rays by B. Ray Hawke (University of Hawaii) and colleagues at the University of Hawaii, NovaSol, Cornell University, National Air and Space Museum, and Northwestern University. These scientists have found that the mere presence of crater rays is not a reliable indicator that the crater is young, as once thought, and that the working definition of the Copernican/Eratosthenian (C/E) boundary should be reconsidered. The team used Earth-based spectral and radar data with FeO, TiO2, and optical maturity maps derived from Clementine UVVIS images to determine the origin and composition of selected lunar ray segments. They conclude that the optical maturity parameter, which uses chemical analyses of lunar samples as its foundation, should be used to redefine the C/E boundary. Under this classification, the Copernican System would be defined as the time required for an immature surface to reach full optical maturity.

  4. MAPT and PAICE: Tools for time series and single time point transcriptionist visualization and knowledge discovery

    PubMed Central

    Hosseini, Parsa; Tremblay, Arianne; Matthews, Benjamin F; Alkharouf, Nadim W

    2012-01-01

    With the advent of next-generation sequencing, -omics fields such as transcriptomics have experienced increases in data throughput on the order of magnitudes. In terms of analyzing and visually representing these huge datasets, an intuitive and computationally tractable approach is to map quantified transcript expression onto biochemical pathways while employing datamining and visualization principles to accelerate knowledge discovery. We present two cross-platform tools: MAPT (Mapping and Analysis of Pathways through Time) and PAICE (Pathway Analysis and Integrated Coloring of Experiments), an easy to use analysis suite to facilitate time series and single time point transcriptomics analysis. In unison, MAPT and PAICE serve as a visual workbench for transcriptomics knowledge discovery, data-mining and functional annotation. Both PAICE and MAPT are two distinct but yet inextricably linked tools. The former is specifically designed to map EC accessions onto KEGG pathways while handling multiple gene copies, detection-call analysis, as well as UN/annotated EC accessions lacking quantifiable expression. The latter tool integrates PAICE datasets to drive visualization, annotation, and data-mining. Availability The database is available for free at http://sourceforge.net/projects/paice/http://sourceforge.net/projects/mapt/ PMID:22493539

  5. Bifurcated method and apparatus for floating point addition with decreased latency time

    DOEpatents

    Farmwald, Paul M.

    1987-01-01

    Apparatus for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  6. Using an Adenosine Triphosphate Bioluminescent Assay to Determine Effective Antibiotic Combinations against Carbapenem-Resistant Gram Negative Bacteria within 24 Hours

    PubMed Central

    Cai, Yiying; Leck, Hui; Lim, Tze Peng; Teo, Jocelyn; Lee, Winnie; Hsu, Li Yang; Koh, Tse Hsien; Tan, Thuan Tong; Tan, Thean-Yen; Kwa, Andrea Lay-Hoon

    2015-01-01

    Background Current in vitro combination testing methods involve enumeration by bacterial plating, which is labor-intensive and time-consuming. Measurement of bioluminescence, released when bacterial adenosine triphosphate binds to firefly luciferin-luciferase, has been proposed as a surrogate for bacterial counts. We developed an ATP bioluminescent combination testing assay with a rapid turnaround time of 24h to determine effective antibiotic combinations. Methods 100 strains of carbapenem-resistant (CR) GNB [30 Acinetobacter baumannii (AB), 30 Pseudomonas aeruginosa (PA) and 40 Klebsiella pneumoniae (KP)] were used. Bacterial suspensions (105 CFU/ml) were added to 96-well plates containing clinically achievable concentrations of multiple single and two-antibiotic combinations. At 24h, the luminescence intensity of each well was measured. Receiver operator characteristic curves were plotted to determine optimal luminescence threshold (TRLU) to discriminate between inhibitory/non-inhibitory combinations when compared to viable plating. The unweighted accuracy (UA) [(sensitivity + specificity)/2] of TRLU values was determined. External validation was further done using 50 additional CR-GNB. Results Predictive accuracies of TRLU were high for when all antibiotic combinations and species were collectively analyzed (TRLU = 0.81, UA = 89%). When individual thresholds for each species were determined, UA remained high. Predictive accuracy was highest for KP (TRLU = 0.81, UA = 91%), and lowest for AB (TRLU = 0.83, UA = 87%). Upon external validation, high overall accuracy (91%) was observed. The assay distinguished inhibitory/non-inhibitory combinations with UA of 80%, 94% and 93% for AB, PA and KP respectively. Conclusion We developed an assay that is robust at identifying useful combinations with a rapid turn-around time of 24h, and may be employed to guide the timely selection of effective antibiotic combinations. PMID:26460891

  7. Short communication: The effect of 4 antiseptic compounds on umbilical cord healing and infection rates in the first 24 hours in dairy calves from a commercial herd.

    PubMed

    Robinson, A L; Timms, L L; Stalder, K J; Tyler, H D

    2015-08-01

    The objective of this study was to compare the effect of 4 antiseptic compounds on the healing rate and incidence of infection of umbilical cords in newborn calves (n=60). Late gestation Jersey cows were monitored at a commercial farm (Sioux Jersey, Salix, IA) and newborn purebred (n=30) and crossbred (n=30) calves were obtained within 30min after birth. Calves were alternately assigned by birth order to 4 treatment groups: 7% tincture of iodine, 0.1% chlorine created using a novel chlorine disinfectant technology, chlorohexidine gluconate 4.0% wt/vol, and 10% trisodium citrate. Prior to dipping (within 30min of birth), diameter of the umbilical cords (as an indicator of cord drying and healing) were determined using digital calipers. In addition, as an indicator of umbilical infections, surface temperature of the umbilical stump (along with a reference point at the midpoint of the sternum) was determined using a dual-laser infrared thermometer. These measurements were all repeated at 24±1 h of age. All data were analyzed using mixed model methods. All models included fixed effects of breed (Jersey or Jersey cross), sex (bull or heifer), and treatment. Fixed effect interactions were not included in the statistical model due to the relatively small sample size. No treatment differences were noted for healing rate of umbilical cords. Initially, mean umbilical cord diameter was 22.84±3.89mm and cords healed to a mean diameter of 7.64±4.12mm at 24 h of age. No umbilical infections were noted for calves on any treatment during the course of this study. Mean surface temperature of the umbilical stump was 33.1±2.2°C at birth (1.5±1.6°C higher than the sternal reference temperature), and at 24±1 h of age the mean temperature of the umbilical stump was 33.0±4.3°C (0.5±1.8°C lower than the sternal reference temperature). These data suggest that these antiseptic compounds are equally effective for preventing infections and permitting healing of the umbilical cord

  8. Synchronization by low-amplitude light-dark cycles of 24-hour pineal and plasma melatonin rhythms of hatchling European starlings (Sturnus vulgaris).

    PubMed

    Gwinner, E; Zeman, M; Klaassen, M

    1997-11-01

    In young European starlings, as in other avian species, high-amplitude 24-hr rhythms in plasma and pineal melatonin are already present around the time of hatching. In chickens this rhythmicity results at least partly from the light sensitivity of the melatonin-producing and -secreting system. In contrast to the chicken, the starling is a hole-nesting bird, and it seemed questionable whether the low light intensities in the nest are sufficient to synchronize perinatal melatonin rhythms. We therefore exposed starling eggs to light cycles roughly simulating those measured in nest-boxes, i.e., an 11-hr phase of complete darkness and a 13-hr phase consisting of 15 min of dim light (10 lux) alternating with 30 min of darkness. For one group the photophase lasted from 0600 to 1900 hr; for the other group the photophase lasted from 1800 to 0700 hr. In approximately 10-hr-old hatchlings of both groups, plasma and pineal melatonin concentrations were high during the dark phase and low during the light phase. We conclude that perinatal low-amplitude light intensity changes of the kind experienced by hatching starlings in the field are sufficient for synchronizing the melatonin-producing and -secreting system in the pineal and possibly other organs. PMID:9462849

  9. [Ambulatory recording of esophageal pH over a 24-hour period in a population of 27 control subjects: analysis of technical and methodological factors influencing results].

    PubMed

    Gignoux, C; Bonnet-Eymard, P O; Hostein, J; Fournet, J

    1987-01-01

    Twenty-four hour pH monitoring is used increasingly as a technique for diagnosis of gastro-esophageal reflux (GER). The Synectics recording apparatus (Stockholm, Sweden) was used in 27 ambulatory control subjects in order to: identify the variations of the data-dependent factors (electrodes, buffer solutions, calibration, placement of esophageal electrode). The consequences of these variations were evaluated by studying the measurement deflection after 24 h, baseline variations, and a comparative double pH esophageal recording with reference equipment for 3 h postprandial; to provide normal values for several parameters of GER measurement under the conditions of this study (total number of reflux, number of reflux episodes longer than 5 min, duration of the longest reflux, percentage of time during which pH was less than 4.0). Important interindividual variations were observed. When interpreting the results provided by this type of apparatus, one should take into account these large variations due, first, to the technique used and second, to the conditions of ambulatory recording. PMID:3556956

  10. A phase II study of paclitaxel, weekly, 24-hour continuous infusion 5-fluorouracil, folinic acid and cisplatin in patients with advanced gastric cancer

    PubMed Central

    Kollmannsberger, C; Quietzsch, D; Haag, C; Lingenfelser, T; Schroeder, M; Hartmann, J T; Baronius, W; Hempel, V; Clemens, M; Kanz, L; Bokemeyer, C

    2000-01-01

    To evaluate the toxicity and efficacy of combination chemotherapy with paclitaxel, cisplatin and 24 h continuous infusion of 5-FU/folinic acid in patients (pts) with unresectable, locally advanced or metastatic gastric adenocarcinoma. Forty-five chemotherapy-naive pts (28 male and 17 female) with a median age of 60 years (range 35–74) were enrolled. 5-FU 2 g/m2was given weekly over 24 h i.v. preceded by folinic acid 500 mg/m2as a 2 h infusion. Paclitaxel 175 mg/m2was administered as a 3 h-infusion on days 1 and 22 and cisplatin 50 mg/m2as 1 h infusion on days 8 and 29. Six weeks of therapy (days 1, 8, 15, 22, 29, 36) followed by 2 weeks rest were considered one cycle. A median of 3 cycles (range 1–4) were administered to 45 pts assessable for response, survival and toxicity. Five pts (11%) obtained a CR and 18 pts (40%) a PR (ORR 51%; 95% Cl: 35.8–66.3%). Responses were achieved in the liver, lymph nodes, lungs and at the site of the primary tumour. Nine pts (20%) had stable disease. Thirteen pts (29%) were considered to have failed treatment, 8 pts (18%) due to progressive disease and 5 pts (11%) who did not receive one complete cycle of therapy due to acute non-haematologic toxicity. The median progression-free and overall survival times were 9 months (range 1–36+) and 14 months (range 2–36+), respectively. Neutropenia WHO III°/IV° occurred in 7 pts (15%) with only 1 pt having grade IV. Additional non-haematologic WHO III°/IV° toxicities included nausea/vomiting in 5 (11%), alopecia in 22 (49%), and diarrhoea in 1 patient each (2%). Dose reductions or treatment delays were necessary in 8 pts (17%), mainly due to neutropenia. All pts were treated on an outpatient basis. The combination of paclitaxel, cisplatin and continuously infused 5-FU/folinic acid appears to be a highly active regimen for the treatment of pts with advanced gastric cancer. While the overall acceptable toxicity allows its use in the palliative setting, it may also be an attractive

  11. 24-hour urinary aldosterone excretion rate

    MedlinePlus

    ... RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 22nd ed. Philadelphia, PA: Elsevier Saunders; ... by: Brent Wisse, MD, Associate Professor of Medicine, Division of Metabolism, Endocrinology & Nutrition, University ...

  12. Toys Remain Viral Playground for 24 Hours

    MedlinePlus

    ... a toy's surface at typical indoor temperatures and humidity levels. Specifically, they tested the ability of so- ... East Respiratory Syndrome (MERS). At 60 percent relative humidity, 1 percent of the virus remained infectious on ...

  13. Nonparametric decomposition of quasi-periodic time series for change-point detection

    NASA Astrophysics Data System (ADS)

    Artemov, Alexey; Burnaev, Evgeny; Lokot, Andrey

    2015-12-01

    The paper is concerned with the sequential online change-point detection problem for a dynamical system driven by a quasiperiodic stochastic process. We propose a multicomponent time series model and an effective online decomposition algorithm to approximate the components of the models. Assuming the stationarity of the obtained components, we approach the change-point detection problem on a per-component basis and propose two online change-point detection schemes corresponding to two real-world scenarios. Experimental results for decomposition and detection algorithms for synthesized and real-world datasets are provided to demonstrate the efficiency of our change-point detection framework.

  14. A novel memristive time-delay chaotic system without equilibrium points

    NASA Astrophysics Data System (ADS)

    Pham, V.-T.; Vaidyanathan, S.; Volos, C. K.; Jafari, S.; Kuznetsov, N. V.; Hoang, T. M.

    2016-02-01

    Memristor and time-delay are potential candidates for constructing new systems with complex dynamics and special features. A novel time-delay system with a presence of memristive device is proposed in this work. It is worth noting that this memristive time-delay system can generate chaotic attractors although it possesses no equilibrium points. In addition, a circuitry implementation of such time-delay system has been introduced to show its feasibility.

  15. Kick-Off, Half-Time, and Over-Time: Flexible Scheduling Scores Points

    ERIC Educational Resources Information Center

    McLeod, Jade

    2005-01-01

    When faculty members at Furman Middle School in Sumter, South Carolina, expressed concern about the lack of time in each day to provide the interventions, remediation, and enrichment the students needed to be prepared for state testing, their principal devised a creative flexible schedule to meet student needs. These include: (1) a morning…

  16. Knee Point Search Using Cascading Top-k Sorting with Minimized Time Complexity

    PubMed Central

    Tseng, Shian-Shyong

    2013-01-01

    Anomaly detection systems and many other applications are frequently confronted with the problem of finding the largest knee point in the sorted curve for a set of unsorted points. This paper proposes an efficient knee point search algorithm with minimized time complexity using the cascading top-k sorting when a priori probability distribution of the knee point is known. First, a top-k sort algorithm is proposed based on a quicksort variation. We divide the knee point search problem into multiple steps. And in each step an optimization problem of the selection number k is solved, where the objective function is defined as the expected time cost. Because the expected time cost in one step is dependent on that of the afterwards steps, we simplify the optimization problem by minimizing the maximum expected time cost. The posterior probability of the largest knee point distribution and the other parameters are updated before solving the optimization problem in each step. An example of source detection of DNS DoS flooding attacks is provided to illustrate the applications of the proposed algorithm. PMID:24068888

  17. A Well-Clear Volume Based on Time to Entry Point

    NASA Technical Reports Server (NTRS)

    Narkawicz, Anthony J.; Munoz, Cesar A.; Upchurch, Jason M.; Chamberlain, James P.; Consiglio, Maria C.

    2014-01-01

    A well-clear volume is a key component of NASA's Separation Assurance concept for the integration of UAS in the NAS. This paper proposes a mathematical definition of the well-clear volume that uses, in addition to distance thresholds, a time threshold based on time to entry point (TEP). The mathematical model that results from this definition is more conservative than other candidate definitions of the wellclear volume that are based on range over closure rate and time to closest point of approach.

  18. Spatially shifting temporal points: estimating pooled within-time series variograms for scarce hydrological data

    NASA Astrophysics Data System (ADS)

    Bhowmik, A. K.; Cabral, P.

    2015-02-01

    Estimation of pooled within-time series (PTS) variograms is a frequently used technique for geostatistical interpolation of continuous hydrological variables in spatial data-scarce regions conditional that time series are available. The only available method for estimating PTS variograms averages semivariances, which are computed for individual time steps, over each spatial lag within a pooled time series. However, semivariances computed by a~few paired comparisons for individual time steps are erratic and hence they may hamper precision of PTS variogram estimation. Here, we outlined an alternative method for estimating PTS variograms by spatializing temporal data points and shifting them. The data were pooled by ensuring consistency of spatial structure and stationarity within a time series, while pooling sufficient number of data points for reliable variogram estimation. The pooled spatial data point sets from different time steps were assigned to different coordinate sets on the same space. Then a semivariance was computed for each spatial lag within a pooled time series by comparing all point pairs separable by that spatial lag, and a PTS variogram was estimated by controlling the lower and upper boundary of spatial lags. Our method showed higher precision than the available method for PTS variogram estimation and was developed by using the freely available R open source software environment. The method will reduce uncertainty for spatial variability modeling while preserving spatiotemporal properties of data for geostatistical interpolation of hydrological variables in spatial data-scarce developing countries.

  19. Anomalous parity-time-symmetry transition away from an exceptional point

    NASA Astrophysics Data System (ADS)

    Ge, Li

    2016-07-01

    Parity-time (PT ) symmetric systems have two distinguished phases, e.g., one with real-energy eigenvalues and the other with complex-conjugate eigenvalues. To enter one phase from the other, it is believed that the system must pass through an exceptional point, which is a non-Hermitian degenerate point with coalesced eigenvalues and eigenvectors. Here we reveal an anomalous PT transition that takes place away from an exceptional point in a nonlinear system: as the nonlinearity increases, the original linear system evolves along two distinct PT -symmetric trajectories, each of which can have an exceptional point. However, the two trajectories collide and vanish away from these exceptional points, after which the system is left with a PT -broken phase. We first illustrate this phenomenon using a coupled-mode theory and then exemplify it using paraxial wave propagation in a transverse periodic potential.

  20. Improving our understanding of the Spitzer Space Telescope's pointing drifts

    NASA Astrophysics Data System (ADS)

    Grillmair, Carl J.; Carey, Sean J.; Stauffer, John R.; Ingalls, James G.

    2014-08-01

    Spitzer observations of exoplanets routinely yield photometric accuracies of better than one part in 10,000. However, the attainable precision is limited in part by pointing drifts, which have the effect of moving the target to less stable or less-well characterized regions of Spitzer's IRAC detector arrays. Here we examine a large sample of observing sequences in an effort to identify the causes of these pointing drifts. We find that short term and higher order drifts are correlated on various time scales to the temperatures of components in and around the spacecraft bus, and are most likely due to very slight angular displacements of the star trackers. Despite the constraints imposed by a limited pool of targets, such pointing drifts are best mitigated by optimal scheduling, minimizing large and/or lengthy excursions in telescope pitch angle within 24 hours of a high-precision photometry sequence. Such an effort is currently being initiated by the Spitzer Science Center.

  1. Change-point detection in time-series data by relative density-ratio estimation.

    PubMed

    Liu, Song; Yamada, Makoto; Collier, Nigel; Sugiyama, Masashi

    2013-07-01

    The objective of change-point detection is to discover abrupt property changes lying behind time-series data. In this paper, we present a novel statistical change-point detection algorithm based on non-parametric divergence estimation between time-series samples from two retrospective segments. Our method uses the relative Pearson divergence as a divergence measure, and it is accurately and efficiently estimated by a method of direct density-ratio estimation. Through experiments on artificial and real-world datasets including human-activity sensing, speech, and Twitter messages, we demonstrate the usefulness of the proposed method. PMID:23500502

  2. Multiple Spike Time Patterns Occur at Bifurcation Points of Membrane Potential Dynamics

    PubMed Central

    Toups, J. Vincent; Fellous, Jean-Marc; Thomas, Peter J.; Sejnowski, Terrence J.; Tiesinga, Paul H.

    2012-01-01

    The response of a neuron to repeated somatic fluctuating current injections in vitro can elicit a reliable and precisely timed sequence of action potentials. The set of responses obtained across trials can also be interpreted as the response of an ensemble of similar neurons receiving the same input, with the precise spike times representing synchronous volleys that would be effective in driving postsynaptic neurons. To study the reproducibility of the output spike times for different conditions that might occur in vivo, we somatically injected aperiodic current waveforms into cortical neurons in vitro and systematically varied the amplitude and DC offset of the fluctuations. As the amplitude of the fluctuations was increased, reliability increased and the spike times remained stable over a wide range of values. However, at specific values called bifurcation points, large shifts in the spike times were obtained in response to small changes in the stimulus, resulting in multiple spike patterns that were revealed using an unsupervised classification method. Increasing the DC offset, which mimicked an overall increase in network background activity, also revealed bifurcation points and increased the reliability. Furthermore, the spike times shifted earlier with increasing offset. Although the reliability was reduced at bifurcation points, a theoretical analysis showed that the information about the stimulus time course was increased because each of the spike time patterns contained different information about the input. PMID:23093916

  3. A new method of time difference measurement: The time difference method by dual phase coincidence points detection

    NASA Technical Reports Server (NTRS)

    Zhou, Wei

    1993-01-01

    In the high accurate measurement of periodic signals, the greatest common factor frequency and its characteristics have special functions. A method of time difference measurement - the time difference method by dual 'phase coincidence points' detection is described. This method utilizes the characteristics of the greatest common factor frequency to measure time or phase difference between periodic signals. It can suit a very wide frequency range. Measurement precision and potential accuracy of several picoseconds were demonstrated with this new method. The instrument based on this method is very simple, and the demand for the common oscillator is low. This method and instrument can be used widely.

  4. A mathematical model of saccadic reaction time as a function of the fixation point brightness gain.

    PubMed

    Diaz-Tula, Antonio; Morimoto, Carlos H; Ranvaud, Ronald D

    2015-08-01

    The gap effect refers to a reduction in saccadic reaction time (SRT) to an eccentric target, when the fixation point is removed before the target onset. Though it is known that the gap effect peaks when the fixation point is offset about 200 ms before the onset of the eccentric target, it is unknown how this effect is modulated by stimulus variations. In this paper, we propose and investigate a model of saccadic reaction time as a function of the fixation point brightness gain. The brightness gain is defined as the ratio of the final and initial intensities of the stimulus. We have conducted a typical gap effect experiment with 15 participants, where the brightness of the fixation point was manipulated under four conditions and two gap intervals, at the same time and 200 ms before the onset of the eccentric target. The conditions included removing the fixation point (offset), leaving it with constant brightness (overlap), reducing, and increasing its brightness (lower and higher brightness conditions). Experimental data showed a significant gap effect in the offset and lower brightness conditions when compared to the overlap condition. On the other hand, the SRT was significantly longer for the higher brightness condition than the SRT for the overlap condition. Linear regression analysis using ten values of brightness gain shows that our model fits the data well for the 0- and 200-ms gap, with a coefficient of determination of .89 and .94, respectively. PMID:25962456

  5. Some aspects of improving Multi-GNSS real-time precise point positioning services

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Ge, Maorong; Li, Xingxing; Schuh, Harald

    2016-04-01

    Multi-GNSS is expected to achieve a real-time precise point positioning service with better accuracy and reliability than GPS-only service. In this contribution, we address several critical challenges in implementing a GPS+GLONASS+BeiDou+Galileo service to provide global users with centimeter-level positioning in real-time based on the software system developed at GFZ. The specific issues of improving GLONASS orbit quality by resolving ambiguity over long baselines, estimation of inter-system/frequency biases, ambiguity resolution in real-time clock estimation and positioning, and computation efficiency are discussed and investigated in detail. Experimental validation is carried out based on the data streams of the IGS/MGEX network. The real-time orbit and clock products are assessed by comparison with the IGS/MGEX final products, and orbits are also assessed by overlapping day boundaries and satellite laser ranging. The phase bias (uncalibrated phase delay) products are evaluated by comparison with the post-processing results. It is demonstrated that multi-GNSS can contribute significantly to improving the global real-time precise point positioning service in terms of convergence time and accuracy. Keywords: Multi-GNSS, Real-Time, Precise Orbit Determination, Precise Point Positioning, Ambiguity Resolution, Inter-System/Frequency Bias, Algorithm Efficiency

  6. Equilibrium time-correlation functions for one-dimensional hard-point systems

    NASA Astrophysics Data System (ADS)

    Mendl, Christian B.; Spohn, Herbert

    2014-07-01

    As recently proposed, the long-time behavior of equilibrium time-correlation functions for one-dimensional systems are expected to be captured by a nonlinear extension of fluctuating hydrodynamics. We outline the predictions from the theory aimed at the comparison with molecular dynamics. We report on numerical simulations of a fluid with a hard-shoulder potential and of a hard-point gas with alternating masses. These models have in common that the collision time is zero and their dynamics amounts to iterating collision by collision. The theory is well confirmed, with the twist that the nonuniversal coefficients are still changing at longest accessible times.

  7. GPS/GLONASS time offset monitoring based on combined Precise Point Positioning (PPP) approach

    NASA Astrophysics Data System (ADS)

    Huang, G.; Zhang, Q.; Fu, W.; Guo, H.

    2015-06-01

    A new strategy is proposed to monitor GPS/GLONASS time offsets for common navigation users using a combined GPS/GLONASS Precise Point Positioning (PPP) method based on the orbit and clock products of different time scales. The results of the inter-system GPS/GLONASS time offset, the user time offset and the inter-system device delay difference were obtained using the proposed method. The properties of these results were analyzed in terms of the stability, precision and variation characteristics. Moreover, the practicality of the time offset results in an actual navigation application was tested and demonstrated. The results indicate that the monitoring and prediction of the user time offset, but not the inter-system time offset, has important values for navigation users.

  8. Effective cross-over to granisetron after failure to ondansetron, a randomized double blind study in patients failing ondansetron plus dexamethasone during the first 24 hours following highly emetogenic chemotherapy

    PubMed Central

    de Wit, R; de Boer, A C; vd Linden, G H M; Stoter, G; Sparreboom, A; Verweij, J

    2001-01-01

    In view of the similarity in chemical structure of the available 5HT3-receptor antagonists it is assumed, whilst these agents all act at the same receptor, that failure to one agent would predict subsequent failure to all 5HT3-receptor antagonists. We conducted a randomized double blind trial of granisetron 3 mg plus dexamethasone 10 mg versus continued treatment with ondansetron 8 mg plus dexamethasone 10 mg in patients with protection failure on ondansetron 8 mg plus dexamethasone 10 mg during the first 24 hours following highly emetogenic chemotherapy. Of 40 eligible patients, 21 received ondansetron + dexamethasone and 19 received granisetron + dexamethasone. We found a significant benefit from crossing-over to granisetron after failure on ondansetron. Of the 19 patients who crossed over to granisetron, 9 patients obtained complete protection, whereas this was observed in 1 of the 21 patients continuing ondansetron, P = 0.005. These results indicate that there is no complete cross-resistance between 5HT3-receptor antagonists, and that patients who have acute protection failure on one 5HT3-receptor antagonist should be offered cross-over to another 5HT3-receptor antagonist. © 2001 Cancer Research Campaign  http://www.bjcancer.com PMID:11710819

  9. Portable Dew Point Mass Spectrometry System for Real-Time Gas and Moisture Analysis

    NASA Technical Reports Server (NTRS)

    Arkin, C.; Gillespie, Stacey; Ratzel, Christopher

    2010-01-01

    A portable instrument incorporates both mass spectrometry and dew point measurement to provide real-time, quantitative gas measurements of helium, nitrogen, oxygen, argon, and carbon dioxide, along with real-time, quantitative moisture analysis. The Portable Dew Point Mass Spectrometry (PDP-MS) system comprises a single quadrupole mass spectrometer and a high vacuum system consisting of a turbopump and a diaphragm-backing pump. A capacitive membrane dew point sensor was placed upstream of the MS, but still within the pressure-flow control pneumatic region. Pressure-flow control was achieved with an upstream precision metering valve, a capacitance diaphragm gauge, and a downstream mass flow controller. User configurable LabVIEW software was developed to provide real-time concentration data for the MS, dew point monitor, and sample delivery system pressure control, pressure and flow monitoring, and recording. The system has been designed to include in situ, NIST-traceable calibration. Certain sample tubing retains sufficient water that even if the sample is dry, the sample tube will desorb water to an amount resulting in moisture concentration errors up to 500 ppm for as long as 10 minutes. It was determined that Bev-A-Line IV was the best sample line to use. As a result of this issue, it is prudent to add a high-level humidity sensor to PDP-MS so such events can be prevented in the future.

  10. Precise Point Positioning technique for short and long baselines time transfer

    NASA Astrophysics Data System (ADS)

    Lejba, Pawel; Nawrocki, Jerzy; Lemanski, Dariusz; Foks-Ryznar, Anna; Nogas, Pawel; Dunst, Piotr

    2013-04-01

    In this work the clock parameters determination of several timing receivers TTS-4 (AOS), ASHTECH Z-XII3T (OP, ORB, PTB, USNO) and SEPTENTRIO POLARX4TR (ORB, since February 11, 2012) by use of the Precise Point Positioning (PPP) technique were presented. The clock parameters were determined for several time links based on the data delivered by time and frequency laboratories mentioned above. The computations cover the period from January 1 to December 31, 2012 and were performed in two modes with 7-day and one-month solution for all links. All RINEX data files which include phase and code GPS data were recorded in 30-second intervals. All calculations were performed by means of Natural Resource Canada's GPS Precise Point Positioning (GPS-PPP) software based on high-quality precise satellite coordinates and satellite clock delivered by IGS as the final products. The used independent PPP technique is a very powerful and simple method which allows for better control of antenna positions in AOS and a verification of other time transfer techniques like GPS CV, GLONASS CV and TWSTFT. The PPP technique is also a very good alternative for calibration of a glass fiber link PL-AOS realized at present by AOS. Currently PPP technique is one of the main time transfer methods used at AOS what considerably improve and strengthen the quality of the Polish time scales UTC(AOS), UTC(PL), and TA(PL). KEY-WORDS: Precise Point Positioning, time transfer, IGS products, GNSS, time scales.

  11. A point implicit time integration technique for slow transient flow problems

    SciTech Connect

    Kadioglu, Samet Y.; Berry, Ray A.; Martineau, Richard C.

    2015-05-01

    We introduce a point implicit time integration technique for slow transient flow problems. The method treats the solution variables of interest (that can be located at cell centers, cell edges, or cell nodes) implicitly and the rest of the information related to same or other variables are handled explicitly. The method does not require implicit iteration; instead it time advances the solutions in a similar spirit to explicit methods, except it involves a few additional function(s) evaluation steps. Moreover, the method is unconditionally stable, as a fully implicit method would be. This new approach exhibits the simplicity of implementation of explicit methods and the stability of implicit methods. It is specifically designed for slow transient flow problems of long duration wherein one would like to perform time integrations with very large time steps. Because the method can be time inaccurate for fast transient problems, particularly with larger time steps, an appropriate solution strategy for a problem that evolves from a fast to a slow transient would be to integrate the fast transient with an explicit or semi-implicit technique and then switch to this point implicit method as soon as the time variation slows sufficiently. We have solved several test problems that result from scalar or systems of flow equations. Our findings indicate the new method can integrate slow transient problems very efficiently; and its implementation is very robust.

  12. A real-time recursive filter for the attitude determination of the Spacelab instrument pointing subsystem

    NASA Technical Reports Server (NTRS)

    West, M. E.

    1992-01-01

    A real-time estimation filter which reduces sensitivity to system variations and reduces the amount of preflight computation is developed for the instrument pointing subsystem (IPS). The IPS is a three-axis stabilized platform developed to point various astronomical observation instruments aboard the shuttle. Currently, the IPS utilizes a linearized Kalman filter (LKF), with premission defined gains, to compensate for system drifts and accumulated attitude errors. Since the a priori gains are generated for an expected system, variations result in a suboptimal estimation process. This report compares the performance of three real-time estimation filters with the current LKF implementation. An extended Kalman filter and a second-order Kalman filter are developed to account for the system nonlinearities, while a linear Kalman filter implementation assumes that the nonlinearities are negligible. The performance of each of the four estimation filters are compared with respect to accuracy, stability, settling time, robustness, and computational requirements. It is shown, that for the current IPS pointing requirements, the linear Kalman filter provides improved robustness over the LKF with less computational requirements than the two real-time nonlinear estimation filters.

  13. Time required to obtain representative point-integrated suspended sediment samples

    NASA Astrophysics Data System (ADS)

    Gitto, A.; Venditti, J. G.; Kostaschuk, R.; Church, M. A.

    2013-12-01

    Suspended sediment sampling by conventional bottle sampling methods remains one of the primary ways in which sediment input is measured for sediment budgets. Depth- and point-integrated methods are commonly assumed to accurately represent suspended sediment transport and to contain minimal error, however a recent study of depth-integrated sampling has identified considerable uncertainty between grain-size classes of multiple samples. The uncertainty surrounding point-integrated sampling methods is less well understood. This field study examines at-a-point variability in suspended sediment concentration, grain-size distribution, and grain-size moments to determine if traditional point-integrated methods accurately provide a representative sample of suspended sediment. Here, we present observations of suspended sediment from the sand bedded portion of the Fraser River at Mission, British Columbia, Canada, using a LISST laser-diffraction instrument. Measurements were obtained during the 2010 and 2013 freshet to address scales of sediment transport variability related to turbulence and hydraulic phenomena, respectively. Our observations indicate that the minimum sampling time to obtain representative indicators of suspended sediment transport ranges between 100 to 200 seconds. We are exploring the scales of variability embedded in the flow and the uncertainty in point-integrated sampling. Our goal is to understand the magnitude and the sources of error in suspended sediment measurements, to better understand the sources of uncertainty in sediment budgets.

  14. Search for UHE point-source emission over various time scales

    SciTech Connect

    The CYGNUS Collaboration

    1993-05-01

    A method has been developed to search for pulsed and/or unpulsed ultra high energy (UHE) emission from point sources over a range of time scales. This method has been applied to data accumulated with the CYGNUS extensive air-shower array for events associated with the directions of Cyg X-3, Her X-1, the Crab nebula, and a collection of 48 secondary source candidates. An examination of time scales ranging from minutes to years has yielded results consistent with background fluctuations.

  15. Search for UHE point-source emission over various time scales

    SciTech Connect

    Not Available

    1993-01-01

    A method has been developed to search for pulsed and/or unpulsed ultra high energy (UHE) emission from point sources over a range of time scales. This method has been applied to data accumulated with the CYGNUS extensive air-shower array for events associated with the directions of Cyg X-3, Her X-1, the Crab nebula, and a collection of 48 secondary source candidates. An examination of time scales ranging from minutes to years has yielded results consistent with background fluctuations.

  16. A Point-of-Care Prothrombin Time Test on a Microfluidic Disk Analyzer Using Alternate Spinning.

    PubMed

    Lin, Chia-Hui; Lin, Kun-Wei; Yen, Daniel; Shih, Chih-Hsin; Lu, Chien-Hsing; Wang, Jiunn-Min; Lin, Chi-Yu

    2015-02-01

    In this study, we conducted a fully integrated point-of-care prothrombin time test on a microfluidic disk analyzer. The microfluidic functions integrated on the disk were capable of separating whole blood, decanting plasma, and mixing it with reagents in sequence under alternate spinning. The assay protocol was completed by alternate spinning without using microvalves or surface modification. Clinical sample tests on prothrombin time measurement were conducted by both the microfluidic disk analyzer and the reference instrument used in medical centers. The test results showed a good correlation and agreement between the two instruments. PMID:26353663

  17. A time-domain CMOS oscillator-based thermostat with digital set-point programming.

    PubMed

    Chen, Chun-Chi; Lin, Shih-Hao

    2013-01-01

    This paper presents a time-domain CMOS oscillator-based thermostat with digital set-point programming [without a digital-to-analog converter (DAC) or external resistor] to achieve on-chip thermal management of modern VLSI systems. A time-domain delay-line-based thermostat with multiplexers (MUXs) was used to substantially reduce the power consumption and chip size, and can benefit from the performance enhancement due to the scaling down of fabrication processes. For further cost reduction and accuracy enhancement, this paper proposes a thermostat using two oscillators that are suitable for time-domain curvature compensation instead of longer linear delay lines. The final time comparison was achieved using a time comparator with a built-in custom hysteresis to generate the corresponding temperature alarm and control. The chip size of the circuit was reduced to 0.12 mm2 in a 0.35-mm TSMC CMOS process. The thermostat operates from 0 to 90 °C, and achieved a fine resolution better than 0.05 °C and an improved inaccuracy of ± 0.6 °C after two-point calibration for eight packaged chips. The power consumption was 30 µW at a sample rate of 10 samples/s. PMID:23385403

  18. Comparison of validity of food group intake by food frequency questionnaire between pre- and post- adjustment estimates derived from 2-day 24-hour recalls in combination with the probability of consumption.

    PubMed

    Kim, Dong Woo; Oh, Se-Young; Kwon, Sung-Ok; Kim, Jeongseon

    2012-01-01

    Validation of a food frequency questionnaire (FFQ) utilising a short-term measurement method is challenging when the reference method does not accurately reflect the usual food intake. In addition, food group intake that is not consumed on daily basis is more critical when episodically consumed foods are related and compared. To overcome these challenges, several statistical approaches have been developed to determine usual food intake distributions. The Multiple Source Method (MSM) can calculate the usual food intake by combining the frequency questions of an FFQ with the short-term food intake amount data. In this study, we applied the MSM to estimate the usual food group intake and evaluate the validity of an FFQ with a group of 333 Korean children (aged 3-6 y) who completed two 24-hour recalls (24HR) and one FFQ in 2010. After adjusting the data using the MSM procedure, the true rate of non-consumption for all food groups was less than 1% except for the beans group. The median Spearman correlation coefficients against FFQ of the mean of 2-d 24HRs data and the MSM-adjusted data were 0.20 (range: 0.11 to 0.40) and 0.35 (range: 0.14 to 0.60), respectively. The weighted kappa values against FFQ ranged from 0.08 to 0.25 for the mean of 2-d 24HRs data and from 0.10 to 0.41 for the MSM-adjusted data. For most food groups, the MSM-adjusted data showed relatively stronger correlations against FFQ than raw 2-d 24HRs data, from 0.03 (beverages) to 0.34 (mushrooms). The results of this study indicated that the application of the MSM, which was a better estimate of the usual intake, could be worth considering in FFQ validation studies among Korean children. PMID:22938437

  19. Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: Advanced Sleep-Wake Phase Disorder (ASWPD), Delayed Sleep-Wake Phase Disorder (DSWPD), Non-24-Hour Sleep-Wake Rhythm Disorder (N24SWD), and Irregular Sleep-Wake Rhythm Disorder (ISWRD). An Update for 2015

    PubMed Central

    Auger, R. Robert; Burgess, Helen J.; Emens, Jonathan S.; Deriy, Ludmila V.; Thomas, Sherene M.; Sharkey, Katherine M.

    2015-01-01

    A systematic literature review and meta-analyses (where appropriate) were performed and the GRADE approach was used to update the previous American Academy of Sleep Medicine Practice Parameters on the treatment of intrinsic circadian rhythm sleep-wake disorders. Available data allowed for positive endorsement (at a second-tier degree of confidence) of strategically timed melatonin (for the treatment of DSWPD, blind adults with N24SWD, and children/ adolescents with ISWRD and comorbid neurological disorders), and light therapy with or without accompanying behavioral interventions (adults with ASWPD, children/adolescents with DSWPD, and elderly with dementia). Recommendations against the use of melatonin and discrete sleep-promoting medications are provided for demented elderly patients, at a second- and first-tier degree of confidence, respectively. No recommendations were provided for remaining treatments/ populations, due to either insufficient or absent data. Areas where further research is needed are discussed. Citation: Auger RR, Burgess HJ, Emens JS, Deriy LV, Thomas SM, Sharkey KM. Clinical practice guideline for the treatment of intrinsic circadian rhythm sleep-wake disorders: advanced sleep-wake phase disorder (ASWPD), delayed sleep-wake phase disorder (DSWPD), non-24-hour sleep-wake rhythm disorder (N24SWD), and irregular sleep-wake rhythm disorder (ISWRD). An update for 2015. J Clin Sleep Med 2015;11(10):1199–1236. PMID:26414986

  20. GPU-accelerated Modeling and Element-free Reverse-time Migration with Gauss Points Partition

    NASA Astrophysics Data System (ADS)

    Zhen, Z.; Jia, X.

    2014-12-01

    Element-free method (EFM) has been applied to seismic modeling and migration. Compared with finite element method (FEM) and finite difference method (FDM), it is much cheaper and more flexible because only the information of the nodes and the boundary of the study area are required in computation. In the EFM, the number of Gauss points should be consistent with the number of model nodes; otherwise the accuracy of the intermediate coefficient matrices would be harmed. Thus when we increase the nodes of velocity model in order to obtain higher resolution, we find that the size of the computer's memory will be a bottleneck. The original EFM can deal with at most 81×81 nodes in the case of 2G memory, as tested by Jia and Hu (2006). In order to solve the problem of storage and computation efficiency, we propose a concept of Gauss points partition (GPP), and utilize the GPUs to improve the computation efficiency. Considering the characteristics of the Gaussian points, the GPP method doesn't influence the propagation of seismic wave in the velocity model. To overcome the time-consuming computation of the stiffness matrix (K) and the mass matrix (M), we also use the GPUs in our computation program. We employ the compressed sparse row (CSR) format to compress the intermediate sparse matrices and try to simplify the operations by solving the linear equations with the CULA Sparse's Conjugate Gradient (CG) solver instead of the linear sparse solver 'PARDISO'. It is observed that our strategy can significantly reduce the computational time of K and Mcompared with the algorithm based on CPU. The model tested is Marmousi model. The length of the model is 7425m and the depth is 2990m. We discretize the model with 595x298 nodes, 300x300 Gauss cells and 3x3 Gauss points in each cell. In contrast to the computational time of the conventional EFM, the GPUs-GPP approach can substantially improve the efficiency. The speedup ratio of time consumption of computing K, M is 120 and the

  1. Analysis of the kinetics of lipid peroxidation in terms of characteristic time-points.

    PubMed

    Pinchuk, Ilya; Lichtenberg, Dov

    2014-02-01

    Measuring peroxidation of aggregated lipids in model systems (liposomes, micelles, emulsions or microemulsions) as well as in samples of biological origin ex vivo (isolated lipoproteins, blood sera or plasma) is widely used in medical and biological investigations, to evaluate the oxidative stress, antioxidants' efficiency and lipid oxidizability in different pathophysiological states. To avoid possible artifacts, such investigations must be based on the time course of peroxidation (i.e. on kinetic studies). To be able to compare complex kinetic profiles, it is important to characterize them in terms of mechanistically meaningful and experimentally unequivocal parameters. In this review, we characterize the typically observed continuous kinetic profiles in terms of a limited number of characteristic time-points (both commonly used and additional time-points and their combinations) that can be derived from experimental time-dependencies. The meaning of each of the experimentally observed characteristic parameters is presented in terms of rate constants and concentrations, derived on the basis of mechanistic considerations. Theoretical expressions for these characteristic parameters are based on a model that includes both the inhibited peroxidation and the uninhibited peroxidation occurring after consumption of the antioxidant(s). Comparison between theoretically predicted dependencies and experimental data support our treatment considered with special emphasis on transition metals-induced peroxidation of lipoproteins. PMID:24333462

  2. Real-Time IGS products verification in the context of their use in Precise Point Positioning

    NASA Astrophysics Data System (ADS)

    Hadas, Tomasz; Bosy, Jaroslaw; Kaplon, Jan; Sierny, Jan

    2013-04-01

    Precise Point Positioning (PPP) is a positioning technique of single GNSS receiver which applies high quality products from permanent GNSS observations to utilize the computational potential of global network analysis. Estimated satellite orbits and clocks corrections are introduced into equation system as known parameters. PPP requires the application of precise products, since their quality directly reflects the positioning accuracy. In June 2007 IGS Real-time Pilot Project has started in order to satisfy real-time users, which is especially important for Precise Point Positioning. Currently available streams including precise orbits, clocks and code biases are standardized on RTCM-SC 104 formats and may be used as a substitute for ultra-rapid products. The target combination product performances are 0.3ns for satellite clock accuracy and orbit accuracy at the level of the IGS Ultra predictions with maximum latency of 10s. This study presents the quality assessment of currently available Real-Time IGS products. Long-term test include comparisons of disseminated information with final and high-rate products, stability assessment over time, as well as latency validation of available RTCM streams.

  3. Detecting Space-Time Alternating Biological Signals Close to the Bifurcation Point

    PubMed Central

    Jia, Zhiheng; Bien, Harold; Entcheva, Emilia

    2011-01-01

    Time-alternating biological signals, i.e., alternans, arise in variety of physiological states marked by dynamic instabilities, e.g., period doubling. Normally, a sequence of large–small–large transients, they can exhibit variable patterns over time and space, including spatial discordance. Capture of the early formation of such alternating regions is challenging because of the spatiotemporal similarities between noise and the small-amplitude alternating signals close to the bifurcation point. We present a new approach for automatic detection of alternating signals in large noisy spatiotemporal datasets by exploiting quantitative measures of alternans evolution, e.g., temporal persistence, and by preserving phase information. The technique specifically targets low amplitude, relatively short alternating sequences and is validated by combinatorics-derived probabilities and empirical datasets with white noise. Using high-resolution optical mapping in live cardiomyocyte networks, exhibiting calcium alternans, we reveal for the first time early fine-scale alternans, close to the noise level, which are linked to the later formation of larger regions and evolution of spatially discordant alternans. This robust method aims at quantification and better understanding of the onset of cardiac arrhythmias and can be applied to general analysis of space-time alternating signals, including the vicinity of the bifurcation point. PMID:19695992

  4. Motion data classification on the basis of dynamic time warping with a cloud point distance measure

    NASA Astrophysics Data System (ADS)

    Switonski, Adam; Josinski, Henryk; Zghidi, Hafedh; Wojciechowski, Konrad

    2016-06-01

    The paper deals with the problem of classification of model free motion data. The nearest neighbors classifier which is based on comparison performed by Dynamic Time Warping transform with cloud point distance measure is proposed. The classification utilizes both specific gait features reflected by a movements of subsequent skeleton joints and anthropometric data. To validate proposed approach human gait identification challenge problem is taken into consideration. The motion capture database containing data of 30 different humans collected in Human Motion Laboratory of Polish-Japanese Academy of Information Technology is used. The achieved results are satisfactory, the obtained accuracy of human recognition exceeds 90%. What is more, the applied cloud point distance measure does not depend on calibration process of motion capture system which results in reliable validation.

  5. Calculation of power spectrums from digital time series with missing data points

    NASA Technical Reports Server (NTRS)

    Murray, C. W., Jr.

    1980-01-01

    Two algorithms are developed for calculating power spectrums from the autocorrelation function when there are missing data points in the time series. Both methods use an average sampling interval to compute lagged products. One method, the correlation function power spectrum, takes the discrete Fourier transform of the lagged products directly to obtain the spectrum, while the other, the modified Blackman-Tukey power spectrum, takes the Fourier transform of the mean lagged products. Both techniques require fewer calculations than other procedures since only 50% to 80% of the maximum lags need be calculated. The algorithms are compared with the Fourier transform power spectrum and two least squares procedures (all for an arbitrary data spacing). Examples are given showing recovery of frequency components from simulated periodic data where portions of the time series are missing and random noise has been added to both the time points and to values of the function. In addition the methods are compared using real data. All procedures performed equally well in detecting periodicities in the data.

  6. An evaluation of explicit time integration schemes for use with the generalized interpolation material point method

    NASA Astrophysics Data System (ADS)

    Wallstedt, P. C.; Guilkey, J. E.

    2008-11-01

    The stability and accuracy of the generalized interpolation material point (GIMP) Method is measured directly through carefully-formulated manufactured solutions over wide ranges of CFL numbers and mesh sizes. The manufactured solutions are described in detail. The accuracy and stability of several time integration schemes are compared via numerical experiments. The effect of various treatments of particle "size" are also considered. The hypothesis that GIMP is most accurate when particles remain contiguous and non-overlapping is confirmed by comparing manufactured solutions with and without this property.

  7. Multiaxis inertial sensing with long-time point source atom interferometry.

    PubMed

    Dickerson, Susannah M; Hogan, Jason M; Sugarbaker, Alex; Johnson, David M S; Kasevich, Mark A

    2013-08-23

    We show that light-pulse atom interferometry with atomic point sources and spatially resolved detection enables multiaxis (two rotation, one acceleration) precision inertial sensing at long interrogation times. Using this method, we demonstrate a light-pulse atom interferometer for 87Rb with 1.4 cm peak wave packet separation and a duration of 2T=2.3 s. The inferred acceleration sensitivity of each shot is 6.7×10(-12)g, which improves on previous limits by more than 2 orders of magnitude. We also measure Earth's rotation rate with a precision of 200 nrad/s. PMID:24010433

  8. Time reversal ultrasound focusing to a point away from the beacon location

    NASA Astrophysics Data System (ADS)

    Sinelnikov, Yegor; Sutin, Alexander; Gandhi, Gaurav; Sarvazyan, Armen

    2012-10-01

    In percutaneous procedures there is often a need to focus therapeutic ultrasound to a predefined area without affecting surrounding tissues. Focusing based on Time Reversal Acoustics (TRA) principles constitutes a promising approach for generating high intensity ultrasound field tailored to the shape of the predefined area. Conventional TRA technique enables ultrasound focusing only at a site, where there is an ultrasound beacon, e.g. piezo-transducer mounted at the tip of a catheter. We developed a method of steering the focus away from the beacon location. The method is based on the measurements of impulse response (IR) in several reference points and calculating virtual IRs for the points outside the reference beacon location. The IR for the point away from the beacon is constructed based on mathematical extrapolation of the measured reference IRs frequency spectra, particularly phases. The effectiveness of extrapolated TRA focusing is explored experimentally and by computer simulation. Potential applications include ultrasounda-ssisted drug delivery, artery recanalization and tumor ablation.

  9. The otolaryngologic manifestations of gastroesophageal reflux disease (GERD): a clinical investigation of 225 patients using ambulatory 24-hour pH monitoring and an experimental investigation of the role of acid and pepsin in the development of laryngeal injury.

    PubMed

    Koufman, J A

    1991-04-01

    Occult (silent) gastroesophageal reflux disease (GER, GERD) is believed to be an important etiologic factor in the development of many inflammatory and neoplastic disorders of the upper aerodigestive tract. In order ot test this hypothesis, a human study and an animal study were performed. The human study consisted primarily of applying a new diagnostic technique (double-probe pH monitoring) to a population of otolaryngology patients with GERD to determine the incidence of overt and occult GERD. The animal study consisted of experiments to evaluate the potential damaging effects of intermittent GER on the larynx. Two hundred twenty-five consecutive patients with otolaryngologic disorders having suspected GERD evaluated from 1985 through 1988 are reported. Ambulatory 24-hour intraesophageal pH monitoring was performed in 197; of those, 81% underwent double-probe pH monitoring, with the second pH probe being placed in the hypopharynx at the laryngeal inlet. Seventy percent of the patients also underwent barium esophagography with videofluoroscopy. The patient population was divided into seven diagnostic subgroups: carcinoma of the larynx (n = 31), laryngeal and tracheal stenosis (n = 33), reflux laryngitis (n = 61), globus pharyngeus (n = 27), dysphagia (n = 25), chronic cough (n = 30), and a group with miscellaneous disorders (n = 18). The most common symptoms were hoarseness (71%), cough (51%), globus (47%), and throat clearing (42%). Only 43% of the patients had gastrointestinal symptoms (heartburn or acid regurgitation). Thus, by traditional symptomatology, GER was occult or silent in the majority of the study population. Twenty-eight patients (12%) refused or could not tolerate pH monitoring. Of the patients undergoing diagnostic pH monitoring, 62% had abnormal esophageal pH studies, and 30% demonstrated reflux into the pharynx. The results of diagnostic pH monitoring for each of the subgroups were as follows (percentage with abnormal studies): carcinoma (71

  10. End points for adjuvant therapy trials: has the time come to accept disease-free survival as a surrogate end point for overall survival?

    PubMed

    Gill, Sharlene; Sargent, Daniel

    2006-06-01

    The intent of adjuvant therapy is to eradicate micro-metastatic residual disease following curative resection with the goal of preventing or delaying recurrence. The time-honored standard for demonstrating efficacy of new adjuvant therapies is an improvement in overall survival (OS). This typically requires phase III trials of large sample size with lengthy follow-up. With the intent of reducing the cost and time of completing such trials, there is considerable interest in developing alternative or surrogate end points. A surrogate end point may be employed as a substitute to directly assess the effects of an intervention on an already accepted clinical end point such as mortality. When used judiciously, surrogate end points can accelerate the evaluation of new therapies, resulting in the more timely dissemination of effective therapies to patients. The current review provides a perspective on the suitability and validity of disease-free survival (DFS) as an alternative end point for OS. Criteria for establishing surrogacy and the advantages and limitations associated with the use of DFS as a primary end point in adjuvant clinical trials and as the basis for approval of new adjuvant therapies are discussed. PMID:16794241

  11. Point Bar and Overbank Deposit Storage Time Distributions in a Simulated Meandering River

    NASA Astrophysics Data System (ADS)

    Ackerman, T. R.; Pizzuto, J. E.

    2015-12-01

    Floodplain storage durations are important geologically and for managing pollutants. They provide necessary input data for sediment routing models, but the functions that describe storage are hard to define with field data. Using a meandering river model, a 36ka simulation is analyzed in 20 year time steps. Channel length, and eroded, deposited, and stored sediment volumes stabilize in under 2ka while the region explored by the river expands as time0.3. The simulated channel was 70m (3 pixels) wide and freely migrated within a 30 by 40km reach simulated with constant erodibility, and mean migration rate ±0.06 channel widths per year. No incision or aggradation was permitted. Sediment storage was partitioned by elevation. Point bar deposits are emplaced immediately as the channel moves away and comprise the lower 40% of a vertical section, while the upper 60% of the floodplain consists of vertically accreted 'overbank' deposits that accumulate with decreasing rates as elevation and distance from the channel increase. Point bar deposits have the highest probability of erosion at 80 years, and contribute 2/3 of eroded material despite representing only 40% of the floodplain volume. When eroded, vertical accretion deposits are 1.25 times older than point bar deposits. Apart from these differences, the storage distributions for both deposits are very similar, though there is much more scatter in the point bar distributions. Eroded sediment 2ka in age is well fit with a power law distribution. On average, 10% of eroded material is <80 years old, 30% from 80 - 500 years, 38% from 500 - 2000 years, 15% from 2ka to 10ka and 7% of eroded material is >10ka in age. However, the fraction older than 10ka is widely variable (0% to 30%, σ = 6.8%) in any 20 year interval. The patchiness and variability in the age of eroded sediment observed in these model results may be similar to natural settings and would be difficult to quantify or address with field measurements.

  12. Real-time estimation of FLE statistics for 3-D tracking with point-based registration.

    PubMed

    Wiles, Andrew D; Peters, Terry M

    2009-09-01

    Target registration error (TRE) has become a widely accepted error metric in point-based registration since the error metric was introduced in the 1990s. It is particularly prominent in image-guided surgery (IGS) applications where point-based registration is used in both image registration and optical tracking. In point-based registration, the TRE is a function of the fiducial marker geometry, location of the target and the fiducial localizer error (FLE). While the first two items are easily obtained, the FLE is usually estimated using an a priori technique and applied without any knowledge of real-time information. However, if the FLE can be estimated in real-time, particularly as it pertains to optical tracking, then the TRE can be estimated more robustly. In this paper, a method is presented where the FLE statistics are estimated from the latest measurement of the fiducial registration error (FRE) statistics. The solution is obtained by solving a linear system of equations of the form Ax=b for each marker at each time frame where x are the six independent FLE covariance parameters and b are the six independent estimated FRE covariance parameters. The A matrix is only a function of the tool geometry and hence the inverse of the matrix can be computed a priori and used at each instant in which the FLE estimation is required, hence minimizing the level of computation at each frame. When using a good estimate of the FRE statistics, Monte Carlo simulations demonstrate that the root mean square of the FLE can be computed within a range of 70-90 microm. Robust estimation of the TRE for an optically tracked tool, using a good estimate of the FLE, will provide two enhancements in IGS. First, better patient to image registration will be obtained by using the TRE of the optical tool as a weighting factor of point-based registration used to map the patient to image space. Second, the directionality of the TRE can be relayed back to the surgeon giving the surgeon the option

  13. Local radial point interpolation (MLRPI) method for solving time fractional diffusion-wave equation with damping

    NASA Astrophysics Data System (ADS)

    Hosseini, Vahid Reza; Shivanian, Elyas; Chen, Wen

    2016-05-01

    The purpose of the current investigation is to determine numerical solution of time-fractional diffusion-wave equation with damping for Caputo's fractional derivative of order α (1 < α ≤ 2). A meshless local radial point interpolation (MLRPI) scheme based on Galerkin weak form is analyzed. The reason of choosing MLRPI approach is that it does not require any background integrations cells, instead integrations are implemented over local quadrature domains which are further simplified for reducing the complication of computation using regular and simple shape. The unconditional stability and convergence with order O (τ 6 - 2 α) are proved, where τ is time stepping. Also, several numerical experiments are illustrated to verify theoretical analysis.

  14. Real-time IP-hologram conversion hardware based on floating point DSPs

    NASA Astrophysics Data System (ADS)

    Oi, Ryutaro; Mishina, Tomoyuki; Yamamoto, Kenji; Okui, Makoto

    2009-02-01

    Holography is a 3-D display method that fully satisfies the visual characteristics of the human eye. However, the hologram must be developed in a darkroom under laser illumination. We attempted hologram generation under white light by adopting an integral photography (IP) technique as the input. In this research, we developed a hardware converter to convert IP input (with 120×66 elemental images) to a hologram with high definition television (HDTV) resolution (approximately 2 million pixels). This conversion could be carried out in real time. In this conversion method, each elemental image can be independently extracted and processed. Our hardware contains twenty 300-MHz floating-point digital signal processors (DSPs) operating in parallel. We verified real-time conversion operations by the implemented hardware.

  15. Scattering experiments with microwave billiards at an exceptional point under broken time-reversal invariance.

    PubMed

    Bittner, S; Dietz, B; Harney, H L; Miski-Oglu, M; Richter, A; Schäfer, F

    2014-03-01

    Scattering experiments with microwave cavities were performed and the effects of broken time-reversal invariance (TRI), induced by means of a magnetized ferrite placed inside the cavity, on an isolated doublet of nearly degenerate resonances were investigated. All elements of the effective Hamiltonian of this two-level system were extracted. As a function of two experimental parameters, the doublet and the associated eigenvectors could be tuned to coalesce at a so-called exceptional point (EP). The behavior of the eigenvalues and eigenvectors when encircling the EP in parameter space was studied, including the geometric amplitude that builds up in the case of broken TRI. A one-dimensional subspace of parameters was found where the differences of the eigenvalues are either real or purely imaginary. There, the Hamiltonians were found to be PT invariant under the combined operation of parity (P) and time reversal (T) in a generalized sense. The EP is the point of transition between both regions. There a spontaneous breaking of PT occurs. PMID:24730915

  16. Computing the three-point correlation function of galaxies in O(N^2) time

    NASA Astrophysics Data System (ADS)

    Slepian, Zachary; Eisenstein, Daniel J.

    2015-12-01

    We present an algorithm that computes the multipole coefficients of the galaxy three-point correlation function (3PCF) without explicitly considering triplets of galaxies. Rather, centring on each galaxy in the survey, it expands the radially binned density field in spherical harmonics and combines these to form the multipoles without ever requiring the relative angle between a pair about the central. This approach scales with number and number density in the same way as the two-point correlation function, allowing run-times that are comparable, and 500 times faster than a naive triplet count. It is exact in angle and easily handles edge correction. We demonstrate the algorithm on the LasDamas SDSS-DR7 mock catalogues, computing an edge corrected 3PCF out to 90 Mpc h-1 in under an hour on modest computing resources. We expect this algorithm will render it possible to obtain the large-scale 3PCF for upcoming surveys such as Euclid, Large Synoptic Survey Telescope (LSST), and Dark Energy Spectroscopic Instrument.

  17. ICESAT Laser Altimeter Pointing, Ranging and Timing Calibration from Integrated Residual Analysis

    NASA Technical Reports Server (NTRS)

    Luthcke, Scott B.; Rowlands, D. D.; Carabajal, C. C.; Harding, D. H.; Bufton, J. L.; Williams, T. A.

    2003-01-01

    On January 12, 2003 the Ice, Cloud and land Elevation Satellite (ICESat) was successfully placed into orbit. The ICESat mission carries the Geoscience Laser Altimeter System (GLAS), which has a primary measurement of short-pulse laser- ranging to the Earth s surface at 1064nm wavelength at a rate of 40 pulses per second. The instrument has collected precise elevation measurements of the ice sheets, sea ice roughness and thickness, ocean and land surface elevations and surface reflectivity. The accurate geolocation of GLAS s surface returns, the spots from which the laser energy reflects on the Earth s surface, is a critical issue in the scientific application of these data. Pointing, ranging, timing and orbit errors must be compensated to accurately geolocate the laser altimeter surface returns. Towards this end, the laser range observations can be fully exploited in an integrated residual analysis to accurately calibrate these geolocation/instrument parameters. ICESat laser altimeter data have been simultaneously processed as direct altimetry from ocean sweeps along with dynamic crossovers in order to calibrate pointing, ranging and timing. The calibration methodology and current calibration results are discussed along with future efforts.

  18. Social behavior in a genetic model of dopamine dysfunction at different neurodevelopmental time points

    PubMed Central

    Kabitzke, P. A.; Simpson, E. H.; Kandel, E. R.; Balsam, P. D.

    2016-01-01

    Impairments in social behavior characterize many neurodevelopmental psychiatric disorders. In fact, the temporal emergence and trajectory of these deficits can define the disorder, specify their treatment and signal their prognosis. The sophistication of mouse models with neurobiological endophenotypes of many aspects of psychiatric diseases has increased in recent years, with the necessity to evaluate social behavior in these models. We adapted an assay for the multimodal characterization of social behavior at different development time points (juvenile, adolescent and adult) in control mice in different social contexts (specifically, different sex pairings). Although social context did not affect social behavior in juvenile mice, it did have an effect on the quantity and type of social interaction as well as ultrasonic vocalizations in both adolescence and adulthood. We compared social development in control mice to a transgenic mouse model of the increase in postsynaptic striatal D2R activity observed in patients with schizophrenia (D2R-OE mice). Genotypic differences in social interactions emerged in adolescence and appeared to become more pronounced in adulthood. That vocalizations emitted from dyads with a D2R-OE subject were negatively correlated with active social behavior while vocalizations from control dyads were positively correlated with both active and passive social behavior also suggest social deficits. These data show that striatal dopamine dysfunction plays an important role in the development of social behavior and mouse models such as the one studied here provide an opportunity for screening potential therapeutics at different developmental time points. PMID:26176662

  19. Alterations in grapevine leaf metabolism upon inoculation with Plasmopara viticola in different time-points.

    PubMed

    Ali, Kashif; Maltese, Federica; Figueiredo, Andreia; Rex, Martina; Fortes, Ana Margarida; Zyprian, Eva; Pais, Maria Salomé; Verpoorte, Robert; Choi, Young Hae

    2012-08-01

    Grapevines are easily infected by plant pathogens. It was found that resistant grapevines induce a wide range of phenolics upon the pathogen-infection. In this study in order to gain insight into these processes in different time-points the metabolic changes during the interaction of two grapevine cultivars, 'Regent' (resistant) and 'Trincadeira' (susceptible), with the downy mildew pathogen (Plasmopara viticola) were investigated. Nuclear magnetic resonance (NMR) spectroscopy on leaf extracts was used at several time points after experimental inoculation. A wide range of metabolites were identified using various two-dimensional (2D)-NMR techniques. Multivariate data analysis characterized both the resistant and the susceptible cultivars and their response against the pathogen. Metabolites responsible for their discrimination were identified as a fertaric acid, caftaric acid, quercetin-3-O-glucoside, linolenic acid, and alanine in the resistant cultivar 'Regent', while the susceptible 'Trincadeira' showed higher levels of glutamate, succinate, ascorbate and glucose. This study portrays the analytical capability of NMR spectroscopy and multivariate data analyses methods for the metabolic profiling of plant samples. The results obtained will underline the role of phenylpropanoids and flavonoids in resistance against biotic stresses which in turn provides a firm platform for the metabolic engineering of grapevine cultivars with higher resistance towards pathogens. PMID:22682569

  20. Time-critical neurological emergencies: the unfulfilled role for point-of-care testing

    PubMed Central

    Knight, William A.; Clark, Joseph F.; Beyette, Fred R.; Pancioli, Arthur

    2010-01-01

    Background Neurological emergencies are common and frequently devastating. Every year, millions of Americans suffer an acute stroke, severe traumatic brain injury, subarachnoid hemorrhage, status epilepticus, or spinal cord injury severe enough to require medical intervention. Aims Full evaluation of the diseases in the acute setting often requires advanced diagnostics, and treatment frequently necessitates transfer to specialized centers. Delays in diagnosis and/or treatment may result in worsened outcomes; therefore, optimization of diagnostics is critical. Methods Point-of-care (POC) testing brings advanced diagnostics to the patient’s bedside in an effort to assist medical providers with real-time decisions based on real-time information. POC testing is usually associated with blood tests (blood glucose, troponin, etc.), but can involve imaging, medical devices, or adapting existing technologies for use outside of the hospital. Noticeably missing from the list of current point-of-care technologies are real-time bedside capabilities that address neurological emergencies. Results Unfortunately, the lack of these technologies may result in delayed identification of patients of these devastating conditions and contribute to less aggressive therapies than is seen with other disease processes. Development of time-dependent technologies appropriate for use with the neurologically ill patient are needed to improve therapies and outcomes. Conclusion POC-CENT is designed to support the development of novel ideas focused on improving diagnostic or prognostic capabilities for acute neurological emergencies. Eligible examples include biomarkers of traumatic brain injury, non-invasive measurements of intracranial pressure or cerebral vasospasm, and improved detection of pathological bacteria in suspected meningitis. PMID:20606822

  1. Two-Time-Point FDG PET/CT: Liver SULmean Repeatability

    PubMed Central

    Tahari, Abdel K.; Paidpally, Vasavi; Chirindel, Alin; Wahl, Richard L.; Subramaniam, Rathan M.

    2016-01-01

    OBJECTIVE The purpose of this study was to evaluate the repeatability of liver mean standardized uptake value normalized to lean body mass (SULmean) in the same patients at different time points within the right lobe of the liver at 18F-FDG PET/CT, in a clinical setting. MATERIALS AND METHODS Two PET/CT studies performed on two different dates from each of 130 patients who had normal livers according to structural imaging were included in this reader study. The mean (± SD) length of time between the studies was 235 ± 192 days. SULmean was measured with a 30-mm diameter spherical volume of interest (VOI) placed within the right lobe of the liver (above, below, and at the level of the main portal vein) by two expert readers. ANOVA, intraclass correlation coefficient (ICC), and Bland-Altman analysis were performed. RESULTS The ICC for the first and second set of studies varied between 0.487 and 0.535 for reader 1 and between 0.472 and 0.545 for reader 2. The mean percentage variation for SULmean between the two time scans for the VOIs placed above, below, and at the level of the main portal vein were 3.55% ± 23.19%, 4.65% ± 23.87%, and 4.30% ± 23.03%, respectively, for reader 1 and 4.49% ± 23.23%, 4.33% ± 23.74%, and 4.48% ± 23.01%, respectively, for reader 2. Using 95% CI, the reference range for intrapatient variations between the studies in liver SULmean was −0.5 to 0.60. CONCLUSION There is only fair repeatability of liver SULmean measured between two time points in the same patient in a clinical setting. Scan-to-scan intrapatient variation in absolute liver SULmean was −0.5 to 0.60. PMID:25615764

  2. Real-Time Single Frequency Precise Point Positioning Using SBAS Corrections.

    PubMed

    Li, Liang; Jia, Chun; Zhao, Lin; Cheng, Jianhua; Liu, Jianxu; Ding, Jicheng

    2016-01-01

    Real-time single frequency precise point positioning (PPP) is a promising technique for high-precision navigation with sub-meter or even centimeter-level accuracy because of its convenience and low cost. The navigation performance of single frequency PPP heavily depends on the real-time availability and quality of correction products for satellite orbits and satellite clocks. Satellite-based augmentation system (SBAS) provides the correction products in real-time, but they are intended to be used for wide area differential positioning at 1 meter level precision. By imposing the constraints for ionosphere error, we have developed a real-time single frequency PPP method by sufficiently utilizing SBAS correction products. The proposed PPP method are tested with static and kinematic data, respectively. The static experimental results show that the position accuracy of the proposed PPP method can reach decimeter level, and achieve an improvement of at least 30% when compared with the traditional SBAS method. The positioning convergence of the proposed PPP method can be achieved in 636 epochs at most in static mode. In the kinematic experiment, the position accuracy of the proposed PPP method can be improved by at least 20 cm relative to the SBAS method. Furthermore, it has revealed that the proposed PPP method can achieve decimeter level convergence within 500 s in the kinematic mode. PMID:27517930

  3. Processing 3D flash LADAR point-clouds in real-time for flight applications

    NASA Astrophysics Data System (ADS)

    Craig, R.; Gravseth, I.; Earhart, R. P.; Bladt, J.; Barnhill, S.; Ruppert, L.; Centamore, C.

    2007-04-01

    Ball Aerospace & Technologies Corp. has demonstrated real-time processing of 3D imaging LADAR point-cloud data to produce the industry's first time-of-flight (TOF) 3D video capability. This capability is uniquely suited to the rigorous demands of space and airborne flight applications and holds great promise in the area of autonomous navigation. It will provide long-range, three dimensional video information to autonomous flight software or pilots for immediate use in rendezvous and docking, proximity operations, landing, surface vision systems, and automatic target recognition and tracking. This is enabled by our new generation of FPGA based "pixel-tube" processors, coprocessors and their associated algorithms which have led to a number of advancements in high-speed wavefront processing along with additional advances in dynamic camera control, and space laser designs based on Ball's CALIPSO LIDAR. This evolution in LADAR is made possible by moving the mechanical complexity required for a scanning system into the electronics, where production, integration, testing and life-cycle costs can be significantly reduced. This technique requires a state of the art TOF read-out integrated circuit (ROIC) attached to a sensor array to collect high resolution temporal data, which is then processed through FPGAs. The number of calculations required to process the data is greatly reduced thanks to the fact that all points are captured at the same time and thus correlated. This correlation allows extremely efficient FPGA processing. This capability has been demonstrated in prototype form at both Marshal Space Flight Center and Langley Research Center on targets that represent docking and landing scenarios. This report outlines many aspects of this work as well as aspects of our recent testing at Marshall's Flight Robotics Laboratory.

  4. Comparison of Result Times Between Urine and Whole Blood Point-of-care Pregnancy Testing

    PubMed Central

    Gottlieb, Michael; Wnek, Kristopher; Moskoff, Jordan; Christian, Errick; Bailitz, John

    2016-01-01

    Introduction Point-of-care (POC) pregnancy testing is commonly performed in the emergency department (ED). One prior study demonstrated equivalent accuracy between urine and whole blood for one common brand of POC pregnancy testing. Our study sought to determine the difference in result times when comparing whole blood versus urine for the same brand of POC pregnancy testing. Methods We conducted a prospective, observational study at an urban, academic, tertiary care hospital comparing the turnaround time between order and result for urine and whole blood pregnancy tests collected according to standard protocol without intervention from the investigators. After the blood was collected, the nurse would place three drops onto a Beckman Coulter ICON 25 Rapid HCG bedside pregnancy test and set a timer for 10 minutes. At the end of the 10 minutes, the result and time were recorded on an encoded data sheet and not used clinically. The same make and model analyzer was also used for urine tests in the lab located within the ED. The primary outcome was the difference in mean turnaround time between whole blood in the ED and urine testing in the adjacent lab results. Concordance between samples was assessed as a secondary outcome. Results 265 total patients were included in the study. The use of whole blood resulted in a mean time savings of 21 minutes (95% CI 16–25 minutes) when compared with urine (p<0.001). There was 99.6% concordance between results, with one false negative urine specimen with a quantitative HCG level of 81 mIU/L. Conclusion Our results suggest that the use of whole blood in place of urine for bedside pregnancy testing may reduce the total result turnaround time without significant changes in accuracy in this single-center study. PMID:27429695

  5. Time-Dependent Searches for Neutrino Point Sources with the IceCube Observatory

    NASA Astrophysics Data System (ADS)

    Baker, Michael Francis

    The IceCube Neutrino Observatory is a km³ detector which recently completed construction at the geographic South Pole. Here we present four searches for flaring point-sources sources of neutrinos using IceCube data using maximum-likelihood techniques. For the first time, a search is performed over the entire parameter space of energy, direction and time with sensitivity to neutrino flares lasting between 20 mus and a year duration from astrophysical sources. This work is also an important step for the IceCube experiment in utilizing a multi-messenger approach, driving IceCube neutrino analysis with information from photon observatories. The use of time information is useful since integrated searches over time are less sensitive to flares as they are affected by a larger background of atmospheric neutrinos and moons that can be reduced by the use of additional timing information. Flaring sources considered here, such as active galactic nuclei and gamma-ray bursts, are promising candidate neutrino emitters. One search is "untriggered" in the sense that it looks for any possible flare in the entire sky. The other two searches are triggered by multi-wavelength information on flares. One triggered search uses lightcurves from Fermi-LAT which provides continuous monitoring. A second triggered search uses information where the flux states have been measured only for short periods of time near the flares. A search for periodic emission of neutrinos is also performed on binary systems in the galaxy which are thought to be sources of particle acceleration. The searches use data taken by 40 strings of IceCube between Apr 5, 2008 and May 20, 2009 and by 59 strings of IceCube between May 20, 2009 and May 31, 2010. The results from all searches are compatible with a fluctuation of the background.

  6. Double point source W-phase inversion: Real-time implementation and automated model selection

    NASA Astrophysics Data System (ADS)

    Nealy, Jennifer L.; Hayes, Gavin P.

    2015-12-01

    Rapid and accurate characterization of an earthquake source is an extremely important and ever evolving field of research. Within this field, source inversion of the W-phase has recently been shown to be an effective technique, which can be efficiently implemented in real-time. An extension to the W-phase source inversion is presented in which two point sources are derived to better characterize complex earthquakes. A single source inversion followed by a double point source inversion with centroid locations fixed at the single source solution location can be efficiently run as part of earthquake monitoring network operational procedures. In order to determine the most appropriate solution, i.e., whether an earthquake is most appropriately described by a single source or a double source, an Akaike information criterion (AIC) test is performed. Analyses of all earthquakes of magnitude 7.5 and greater occurring since January 2000 were performed with extended analyses of the September 29, 2009 magnitude 8.1 Samoa earthquake and the April 19, 2014 magnitude 7.5 Papua New Guinea earthquake. The AIC test is shown to be able to accurately select the most appropriate model and the selected W-phase inversion is shown to yield reliable solutions that match published analyses of the same events.

  7. Double point source W-phase inversion: Real-time implementation and automated model selection

    USGS Publications Warehouse

    Nealy, Jennifer; Hayes, Gavin

    2015-01-01

    Rapid and accurate characterization of an earthquake source is an extremely important and ever evolving field of research. Within this field, source inversion of the W-phase has recently been shown to be an effective technique, which can be efficiently implemented in real-time. An extension to the W-phase source inversion is presented in which two point sources are derived to better characterize complex earthquakes. A single source inversion followed by a double point source inversion with centroid locations fixed at the single source solution location can be efficiently run as part of earthquake monitoring network operational procedures. In order to determine the most appropriate solution, i.e., whether an earthquake is most appropriately described by a single source or a double source, an Akaike information criterion (AIC) test is performed. Analyses of all earthquakes of magnitude 7.5 and greater occurring since January 2000 were performed with extended analyses of the September 29, 2009 magnitude 8.1 Samoa earthquake and the April 19, 2014 magnitude 7.5 Papua New Guinea earthquake. The AIC test is shown to be able to accurately select the most appropriate model and the selected W-phase inversion is shown to yield reliable solutions that match published analyses of the same events.

  8. In situ timing and pointing verification of the ICESat altimeter using a ground-based system

    NASA Astrophysics Data System (ADS)

    Magruder, L.; Silverberg, E.; Webb, C.; Schutz, B.

    2005-11-01

    To provide validation of the ICESat laser altimeter time of measurement and geolocation, a ground-based technique was implemented at White Sands Space Harbor (WSSH), during the Laser 2a and 3a operational periods. The activities used an electro-optical detection system and a passive array of corner cube retro reflectors (CCR). The detectors and the CCRs were designed to provide an independent assessment of the laser footprint location, while the detectors also provide timing verification. This ground-based system unambiguously validated the elevation product time tag to 3 μsec +/- 1 μsec. In addition, the ground equipment provided in situ geolocations of the laser pulse. Comparing the in situ results to the ICESat GLA14 data product the positions differ by 10.6 m +/- 4.5 m for Laser 2a (Release 21) operations and 7.5 m +/- 6.6 m for Laser 3a (Release 23). These comparisons correlate to pointing validations at this site, for the specific overflight configurations.

  9. Implementation of a Point Algorithm for Real-Time Convex Optimization

    NASA Technical Reports Server (NTRS)

    Acikmese, Behcet; Motaghedi, Shui; Carson, John

    2007-01-01

    The primal-dual interior-point algorithm implemented in G-OPT is a relatively new and efficient way of solving convex optimization problems. Given a prescribed level of accuracy, the convergence to the optimal solution is guaranteed in a predetermined, finite number of iterations. G-OPT Version 1.0 is a flight software implementation written in C. Onboard application of the software enables autonomous, real-time guidance and control that explicitly incorporates mission constraints such as control authority (e.g. maximum thrust limits), hazard avoidance, and fuel limitations. This software can be used in planetary landing missions (Mars pinpoint landing and lunar landing), as well as in proximity operations around small celestial bodies (moons, asteroids, and comets). It also can be used in any spacecraft mission for thrust allocation in six-degrees-of-freedom control.

  10. Single-point position and transition defects in continuous time quantum walks

    PubMed Central

    Li, Z. J.; Wang, J. B.

    2015-01-01

    We present a detailed analysis of continuous time quantum walks (CTQW) with both position and transition defects defined at a single point in the line. Analytical solutions of both traveling waves and bound states are obtained, which provide valuable insight into the dynamics of CTQW. The number of bound states is found to be critically dependent on the defect parameters, and the localized probability peaks can be readily obtained by projecting the state vector of CTQW on to these bound states. The interference between two bound states are also observed in the case of a transition defect. The spreading of CTQW probability over the line can be finely tuned by varying the position and transition defect parameters, offering the possibility of precision quantum control of the system. PMID:26323855

  11. Undergraduate Consent Form Reading in Relation to Conscientiousness, Procrastination, and the Point-of-Time Effect.

    PubMed

    Theiss, Justin D; Hobbs, William B; Giordano, Peter J; Brunson, Olivia M

    2014-07-01

    Informed consent is central to conducting ethical research with human participants. The present study investigated differences in consent form reading in relation to conscientiousness, procrastination, and the point-of-time (PT) effect among undergraduate participants at a U.S. university. As hypothesized, conscientious participants and those who signed up to participate in a research study more days in advance and for earlier sessions (PT effect) read the consent form more thoroughly. However, procrastination was not related to consent form reading. Most importantly, consent form reading in general was poor, with 80% of participants demonstrating that they had not read the consent form. Conscientious participants were more likely to self-report reading the consent form, irrespective of their measured consent form reading. The article closes with suggestions to improve the process of obtaining informed consent with undergraduate participants. PMID:25746782

  12. The time-space relationships among data points from multispectral spatial scanners

    NASA Technical Reports Server (NTRS)

    Gordon, F.

    1983-01-01

    Multispectral scanner and thematic mapper (TM) data from Landsat satellites are discussed in terms of the perceived 'simultaineity' of the images, which are obtained by scanning techniques. Scanning the scenes ensures that the data points of the images are actually sequential, even if the scan is performed at rates that are fast relative to the motion of the spacecraft. The last datum gathered by the MSS is, in fact, taken 29 sec after the first, witih a 56 m distance being present between pixels. The spacing in uneven from band to band on the TM and analyses of the data to produce an image requires consideration of nonfixed time relationships for different locations on the scan within and among the bands. Additionally, corrective measures must be taken to compensate for instrument jitter and attitude changes.

  13. Near-real-time regional troposphere models for the GNSS precise point positioning technique

    NASA Astrophysics Data System (ADS)

    Hadas, T.; Kaplon, J.; Bosy, J.; Sierny, J.; Wilgan, K.

    2013-05-01

    The GNSS precise point positioning (PPP) technique requires high quality product (orbits and clocks) application, since their error directly affects the quality of positioning. For real-time purposes it is possible to utilize ultra-rapid precise orbits and clocks which are disseminated through the Internet. In order to eliminate as many unknown parameters as possible, one may introduce external information on zenith troposphere delay (ZTD). It is desirable that the a priori model is accurate and reliable, especially for real-time application. One of the open problems in GNSS positioning is troposphere delay modelling on the basis of ground meteorological observations. Institute of Geodesy and Geoinformatics of Wroclaw University of Environmental and Life Sciences (IGG WUELS) has developed two independent regional troposphere models for the territory of Poland. The first one is estimated in near-real-time regime using GNSS data from a Polish ground-based augmentation system named ASG-EUPOS established by Polish Head Office of Geodesy and Cartography (GUGiK) in 2008. The second one is based on meteorological parameters (temperature, pressure and humidity) gathered from various meteorological networks operating over the area of Poland and surrounding countries. This paper describes the methodology of both model calculation and verification. It also presents results of applying various ZTD models into kinematic PPP in the post-processing mode using Bernese GPS Software. Positioning results were used to assess the quality of the developed models during changing weather conditions. Finally, the impact of model application to simulated real-time PPP on precision, accuracy and convergence time is discussed.

  14. On troposphere delay constraining in real-time GNSS Precise Point Positioning

    NASA Astrophysics Data System (ADS)

    Hadas, Tomasz; Kazmierski, Kamil; Bosy, Jaroslaw

    2015-04-01

    A common procedure in Precise Point Positioning (PPP) is to have the adjustment model accounting for the correction to an a priori value of the total troposphere delay (ZTD) given at the first epoch of data processing, and the troposphere wet delay filter is updated epoch by epoch. This approach requires some time so that a change in satellite geometry allows to efficiently de-correlate among tropospheric delay, receiver clock error and height. Empirical troposphere state models and mapping functions are available, however they may not reflect properly the actual state of the troposphere, especially in severe weather conditions. It might be more appropriate to take advantage on a regional troposphere model derived from near real-time (NRT) processing of GBAS network. To evaluate the impact of troposphere constraining in real-time PPP, one week long period was selected, that was characterized with active troposphere conditions. Using the development version of original GNSS-WARP software, a 1 Hz kinematic positioning was performed for 10 selected Polish GBAS stations using IGS Real-Time Service (RTS) products. Two processing strategies were used, one reflecting the common PPP approach and the second with NRT ZTD to constrain the troposphere delay estimates. GPS only and GPS+GLONASS positioning was performed and analyzed using both strategies. For unconstrained solutions, the convergence time of one hour (GPS only) and 15 minutes (GPS+GLONASS) was reached, providing the sub-decimeter accuracy in horizontal and vertical component. However, for some epochs, and outlying height estimates were observed with the residuals reaching up to 0.5m with the estimated error of 0.2m. At the same time, the unconstrained estimated troposphere delay differs up to 12 cm from the reference NRT ZTD solution. In case the troposphere delay is constrained, all three coordinate components remains accurate and precise for entire processing period after the convergence is reached. From the

  15. Hurst exponent analysis of the Earth's Magnetic time signal measured in Teoloyucan Observatory, Mexico.

    NASA Astrophysics Data System (ADS)

    Flores-Marquez, Elsa Leticia; Ramírez-Rojas, Alejandro

    2016-04-01

    The time dynamics of magnetic signal measured, during four years (1998 to 2001), in Teoloyucan Magnetic Observatory, in Mexico, is investigated by means of the Hurst exponent. The observed fluctuations, in the Hurst exponent, show a multifractal behavior that depends on the long-range correlations of the time series. The analysis point out to the presence of two main periodicities (12 hours and 24 hours) in magnetic signal embedded within an antipersistent structure at any timescale, due to diurnal variation. We also depict a 6-h periodic component. Our findings do not put in evidence magnetic variations due to magnetic storms.

  16. Research on space-based optical surveillance's observation strategy of geostationary-orbit's pitch point region

    NASA Astrophysics Data System (ADS)

    Wang, Xue-ying; An, Wei; Wu, Yu-hao; Li, Jun

    2015-03-01

    In order to surveillance the geostationary (GEO) objects, including man-made satellites and space debris, more efficiently, a space-based optical surveillance system was designed in this paper. A strategy to observe the pinch point region was selected because of the GEO objects' dynamics features. That strategy affects the surveillance satellites orbital type and sensor pointing strategy. In order to minimize total surveillance satellites and the revisit time for GEO objects, a equation was set. More than 700 GEO objects' TLE from NASA's website are used for simulation. Results indicate that the revisit time of the surveillance system designed in this paper is less than 24 hours, more than 95% GEO objects can be observed by the designed system.

  17. Two Point Space-Time Correlation of Density Fluctuations Measured in High Velocity Free Jets

    NASA Technical Reports Server (NTRS)

    Panda, Jayanta

    2006-01-01

    Two-point space-time correlations of air density fluctuations in unheated, fully-expanded free jets at Mach numbers M(sub j) = 0.95, 1.4, and 1.8 were measured using a Rayleigh scattering based diagnostic technique. The molecular scattered light from two small probe volumes of 1.03 mm length was measured for a completely non-intrusive means of determining the turbulent density fluctuations. The time series of density fluctuations were analyzed to estimate the integral length scale L in a moving frame of reference and the convective Mach number M(sub c) at different narrow Strouhal frequency (St) bands. It was observed that M(sub c) and the normalized moving frame length scale L*St/D, where D is the jet diameter, increased with Strouhal frequency before leveling off at the highest resolved frequency. Significant differences were observed between data obtained from the lip shear layer and the centerline of the jet. The wave number frequency transform of the correlation data demonstrated progressive increase in the radiative part of turbulence fluctuations with increasing jet Mach number.

  18. Terahertz time domain interferometry of a SIS tunnel junction and a quantum point contact

    SciTech Connect

    Karadi, C

    1995-09-01

    The author has applied the Terahertz Time Domain Interferometric (THz-TDI) technique to probe the ultrafast dynamic response of a Superconducting-Insulating-Superconducting (SIS) tunnel junction and a Quantum Point Contact (QPC). The THz-TDI technique involves monitoring changes in the dc current induced by interfering two picosecond electrical pulses on the junction as a function of time delay between them. Measurements of the response of the Nb/AlO{sub x}/Nb SIS tunnel junction from 75--200 GHz are in full agreement with the linear theory for photon-assisted tunneling. Likewise, measurements of the induced current in a QPC as a function of source-drain voltage, gate voltage, frequency, and magnetic field also show strong evidence for photon-assisted transport. These experiments together demonstrate the general applicability of the THz-TDI technique to the characterization of the dynamic response of any micron or nanometer scale device that exhibits a non-linear I-V characteristic. 133 refs., 49 figs.

  19. Spatial Rainfall Simulation: Trading Time for Space with Multiple Point Statistics.

    NASA Astrophysics Data System (ADS)

    Oriani, F.; Straubhaar, J.; Mariethoz, G.; Renard, P.

    2014-12-01

    Detailed rainfall spatial distribution plays an important role in various applications of hydrological management such as flood forecasting or recharge estimation. However, limited rain gauge network density often makes it difficult to characterize the small-scale variability of rainfall, and reduces the reliability of interpolations methods such as kriging. Here, we test a non-parametric technique that produces spatial rainfall fields by relying on time series data rather than dense spatial data sets. If the velocity of the rain cells is known, the time series can be projected into a one-dimensional space, reflecting the same type of variability observable in the direction of the rain cell displacement. Assuming spatio-temporal ergodicity for a small area, we estimate the mean rainfall cells displacement direction i and velocity vi by optimizing the cross correlation between two subsequent radar images at time t and t+dt. Then, given a time series in the same time lapse R([t,...,t+dt]) and applying the linear transformation R([t,...,t+dt])=S([t,...,t+dt]vi), we obtain a spatial series S generally more densely informed than the available rain-gauge network, used to represent the spatial variability in the direction i. For example, from a 1 min spaced time series R and an estimated velocity v=20 km/h, we obtain a 333 m spaced series S. The obtained spatial series are then employed as a basis to generate 2D spatial rainfall fields using the Direct Sampling (DS), a multiple-point technique that allows simulating complex statistical relations by respecting the similarity of multiple scales patterns. Here the DS is used to complete the 2D field by reproducing one-dimensional patterns borrowed from the spatial series. The approach is tested on the rain-gauge network of the Swiss plateau (Switzerland) and on radar data for the same region. The proposed technique has the potential to characterize realistic spatial fields even for sparse observation networks.

  20. Determination of earthquake magnitude using GPS displacement waveforms from real-time precise point positioning

    NASA Astrophysics Data System (ADS)

    Fang, Rongxin; Shi, Chuang; Song, Weiwei; Wang, Guangxing; Liu, Jingnan

    2014-01-01

    For earthquake and tsunami early warning and emergency response, earthquake magnitude is the crucial parameter to be determined rapidly and correctly. However, a reliable and rapid measurement of the magnitude of an earthquake is a challenging problem, especially for large earthquakes (M > 8). Here, the magnitude is determined based on the GPS displacement waveform derived from real-time precise point positioning (RTPPP). RTPPP results are evaluated with an accuracy of 1 cm in the horizontal components and 2-3 cm in the vertical components, indicating that the RTPPP is capable of detecting seismic waves with amplitude of 1 cm horizontally and 2-3 cm vertically with a confidence level of 95 per cent. In order to estimate the magnitude, the unique information provided by the GPS displacement waveform is the horizontal peak displacement amplitude. We show that the empirical relation of Gutenberg (1945) between peak displacement and magnitude holds up to nearly magnitude 9.0 when displacements are measured with GPS. We tested the proposed method for three large earthquakes. For the 2010 Mw 7.2 El Mayor-Cucapah earthquake, our method provides a magnitude of M7.18 ± 0.18. For the 2011 Mw 9.0 Tohoku-oki earthquake the estimated magnitude is M8.74 ± 0.06, and for the 2010 Mw 8.8 Maule earthquake the value is M8.7 ± 0.1 after excluding some near-field stations. We, therefore, conclude that depending on the availability of high-rate GPS observations, a robust value of magnitude up to 9.0 for a point source earthquake can be estimated within tens of seconds or a few minutes after an event using a few GPS stations close to the epicentre. The rapid magnitude could be as a pre-requisite for tsunami early warning, fast source inversion and emergency response is feasible.

  1. Travel Time Estimation Using Freeway Point Detector Data Based on Evolving Fuzzy Neural Inference System

    PubMed Central

    Tang, Jinjun; Zou, Yajie; Ash, John; Zhang, Shen; Liu, Fang; Wang, Yinhai

    2016-01-01

    Travel time is an important measurement used to evaluate the extent of congestion within road networks. This paper presents a new method to estimate the travel time based on an evolving fuzzy neural inference system. The input variables in the system are traffic flow data (volume, occupancy, and speed) collected from loop detectors located at points both upstream and downstream of a given link, and the output variable is the link travel time. A first order Takagi-Sugeno fuzzy rule set is used to complete the inference. For training the evolving fuzzy neural network (EFNN), two learning processes are proposed: (1) a K-means method is employed to partition input samples into different clusters, and a Gaussian fuzzy membership function is designed for each cluster to measure the membership degree of samples to the cluster centers. As the number of input samples increases, the cluster centers are modified and membership functions are also updated; (2) a weighted recursive least squares estimator is used to optimize the parameters of the linear functions in the Takagi-Sugeno type fuzzy rules. Testing datasets consisting of actual and simulated data are used to test the proposed method. Three common criteria including mean absolute error (MAE), root mean square error (RMSE), and mean absolute relative error (MARE) are utilized to evaluate the estimation performance. Estimation results demonstrate the accuracy and effectiveness of the EFNN method through comparison with existing methods including: multiple linear regression (MLR), instantaneous model (IM), linear model (LM), neural network (NN), and cumulative plots (CP). PMID:26829639

  2. Integrity monitoring in real-time precise point positioning in the presence of ionospheric disturbances

    NASA Astrophysics Data System (ADS)

    Wezka, K.; Galas, R.

    2013-12-01

    Ionospheric disturbances are characterized as fast and random variability in the ionosphere. Those phenomena are difficult to predict, detect and model. Occurrence of some strong ionospheric disturbances can cause, inter alia degradation and interruption of GNSS signals. Therefore they are especially harmful for real-time applications, as for example Precise Point Positioning (PPP) in real time, where one of the most important requirements is to ensure the high level of reliability. In such applications verification and confirmation of a high trust degree towards the estimated coordinates is a very critical issue. In one of the previous papers (K. Wezka, 2012 -Identification of system performance parameters and their usability) two sets of parameters have been proposed for enhance reliability of the PPP. The first one for data quality control (QC) of the raw GNSS observations and the second one for examination of the quality, robustness and performance of various processing approaches (strategies). To the second group the following parameters has been proposed: accuracy, precision, availability, integrity and convergence time. In consideration of perturbation of GNSS signal resulting from sudden ionospheric disturbances, one of the most important demands is effective autonomous integrity monitoring. The poster presents first preliminary results of the applicability of the proposed parameters in order to ensure the high level of reliability/integrity of GNSS observations and positioning results under the presence of strong ionospheric anomalies. The data-set from continuously operated GNSS station located at high latitude, where ionospheric disturbances occur more frequently, were used for the analysis. Various selected Receiver Autonomous Integrity Monitoring (RAIM) approaches for quality control of the GNSS observables are applied to the data sets recorded under different (low/quite and high) ionospheric activities. Based on those analyses the usability of the

  3. Travel Time Estimation Using Freeway Point Detector Data Based on Evolving Fuzzy Neural Inference System.

    PubMed

    Tang, Jinjun; Zou, Yajie; Ash, John; Zhang, Shen; Liu, Fang; Wang, Yinhai

    2016-01-01

    Travel time is an important measurement used to evaluate the extent of congestion within road networks. This paper presents a new method to estimate the travel time based on an evolving fuzzy neural inference system. The input variables in the system are traffic flow data (volume, occupancy, and speed) collected from loop detectors located at points both upstream and downstream of a given link, and the output variable is the link travel time. A first order Takagi-Sugeno fuzzy rule set is used to complete the inference. For training the evolving fuzzy neural network (EFNN), two learning processes are proposed: (1) a K-means method is employed to partition input samples into different clusters, and a Gaussian fuzzy membership function is designed for each cluster to measure the membership degree of samples to the cluster centers. As the number of input samples increases, the cluster centers are modified and membership functions are also updated; (2) a weighted recursive least squares estimator is used to optimize the parameters of the linear functions in the Takagi-Sugeno type fuzzy rules. Testing datasets consisting of actual and simulated data are used to test the proposed method. Three common criteria including mean absolute error (MAE), root mean square error (RMSE), and mean absolute relative error (MARE) are utilized to evaluate the estimation performance. Estimation results demonstrate the accuracy and effectiveness of the EFNN method through comparison with existing methods including: multiple linear regression (MLR), instantaneous model (IM), linear model (LM), neural network (NN), and cumulative plots (CP). PMID:26829639

  4. Triple positive solutions of three-point boundary value problems for p-Laplacian dynamic equations on time scales

    NASA Astrophysics Data System (ADS)

    Hong, Shihuang

    2007-09-01

    In this paper, we present sufficient conditions for the existence of at least three positive solutions of three-point boundary value problems for p-Laplacian dynamic equations on a time scale. To show our main results, we apply a new fixed point theorem due to Avery and Peterson [Three positive fixed points of nonlinear operators on ordered Banach spaces, Comput. Math. Appl. 42 (2001) 313-322].

  5. Real Time Precise Point Positioning: Preliminary Results for the Brazilian Region

    NASA Astrophysics Data System (ADS)

    Marques, Haroldo; Monico, João.; Hirokazu Shimabukuro, Milton; Aquino, Marcio

    2010-05-01

    GNSS positioning can be carried out in relative or absolute approach. In the last years, more attention has been driven to the real time precise point positioning (PPP). To achieve centimeter accuracy with this method in real time it is necessary to have available the satellites precise coordinates as well as satellites clocks corrections. The coordinates can be used from the predicted IGU ephemeris, but the satellites clocks must be estimated in a real time. It can be made from a GNSS network as can be seen from EUREF Permanent Network. The infra-structure to realize the PPP in real time is being available in Brazil through the Brazilian Continuous Monitoring Network (RBMC) together with the Sao Paulo State GNSS network which are transmitting GNSS data using NTRIP (Networked Transport of RTCM via Internet Protocol) caster. Based on this information it was proposed a PhD thesis in the Univ. Estadual Paulista (UNESP) aiming to investigate and develop the methodology to estimate the satellites clocks and realize PPP in real time. Then, software is being developed to process GNSS data in the real time PPP mode. A preliminary version of the software was called PPP_RT and is able to process GNSS code and phase data using precise ephemeris and satellites clocks. The PPP processing can be accomplished considering the absolute satellite antenna Phase Center Variation (PCV), Ocean Tide Loading (OTL), Earth Body Tide, among others. The first order ionospheric effects can be eliminated or minimized by ion-free combination or parameterized in the receiver-satellite direction using a stochastic process, e.g. random walk or white noise. In the case of ionosphere estimation, a pseudo-observable is introduced in the mathematical model for each satellite and the initial value can be computed from Klobuchar model or from Global Ionospheric Map (GIM). The adjustment is realized in the recursive mode and the DIA (Detection Identification and Adaptation) is used for quality control. In

  6. The Way Point Planning Tool: Real Time Flight Planning for Airborne Science

    NASA Technical Reports Server (NTRS)

    He, Yubin; Blakeslee, Richard; Goodman, Michael; Hall, John

    2012-01-01

    Airborne real time observation are a major component of NASA's Earth Science research and satellite ground validation studies. For mission scientist, planning a research aircraft mission within the context of meeting the science objective is a complex task because it requires real time situational awareness of the weather conditions that affect the aircraft track. Multiple aircraft are often involved in the NASA field campaigns the coordination of the aircraft with satellite overpasses, other airplanes and the constantly evolving dynamic weather conditions often determine the success of the campaign. A flight planning tool is needed to provide situational awareness information to the mission scientist and help them plan and modify the flight tracks successfully. Scientists at the University of Alabama Huntsville and the NASA Marshal Space Flight Center developed the Waypoint Planning Tool (WPT), an interactive software tool that enables scientist to develop their own flight plans (also known as waypoints), with point and click mouse capabilities on a digital map filled with time raster and vector data. The development of this Waypoint Planning Tool demonstrates the significance of mission support in responding to the challenges presented during NASA field campaigns. Analyses during and after each campaign helped identify both issues and new requirements, initiating the next wave of development. Currently the Waypoint Planning Tool has gone through three rounds of development and analysis processes. The development of this waypoint tool is directly affected by the technology advances on GIS/Mapping technologies. From the standalone Google Earth application and simple KML functionalities to the Google Earth Plugin and Java Web Start/Applet on web platform, as well as to the rising open source GIS tools with new JavaScript frameworks, the Waypoint planning Tool has entered its third phase of technology advancement. The newly innovated, cross-platform, modular designed

  7. Quantum percolation and transition point of a directed discrete-time quantum walk

    PubMed Central

    Chandrashekar, C. M.; Busch, Th.

    2014-01-01

    Quantum percolation describes the problem of a quantum particle moving through a disordered system. While certain similarities to classical percolation exist, the quantum case has additional complexity due to the possibility of Anderson localisation. Here, we consider a directed discrete-time quantum walk as a model to study quantum percolation of a two-state particle on a two-dimensional lattice. Using numerical analysis we determine the fraction of connected edges required (transition point) in the lattice for the two-state particle to percolate with finite (non-zero) probability for three fundamental lattice geometries, finite square lattice, honeycomb lattice, and nanotube structure and show that it tends towards unity for increasing lattice sizes. To support the numerical results we also use a continuum approximation to analytically derive the expression for the percolation probability for the case of the square lattice and show that it agrees with the numerically obtained results for the discrete case. Beyond the fundamental interest to understand the dynamics of a two-state particle on a lattice (network) with disconnected vertices, our study has the potential to shed light on the transport dynamics in various quantum condensed matter systems and the construction of quantum information processing and communication protocols. PMID:25301394

  8. Quantum percolation and transition point of a directed discrete-time quantum walk.

    PubMed

    Chandrashekar, C M; Busch, Th

    2014-01-01

    Quantum percolation describes the problem of a quantum particle moving through a disordered system. While certain similarities to classical percolation exist, the quantum case has additional complexity due to the possibility of Anderson localisation. Here, we consider a directed discrete-time quantum walk as a model to study quantum percolation of a two-state particle on a two-dimensional lattice. Using numerical analysis we determine the fraction of connected edges required (transition point) in the lattice for the two-state particle to percolate with finite (non-zero) probability for three fundamental lattice geometries, finite square lattice, honeycomb lattice, and nanotube structure and show that it tends towards unity for increasing lattice sizes. To support the numerical results we also use a continuum approximation to analytically derive the expression for the percolation probability for the case of the square lattice and show that it agrees with the numerically obtained results for the discrete case. Beyond the fundamental interest to understand the dynamics of a two-state particle on a lattice (network) with disconnected vertices, our study has the potential to shed light on the transport dynamics in various quantum condensed matter systems and the construction of quantum information processing and communication protocols. PMID:25301394

  9. Brachytherapy in cancer cervix: Time to move ahead from point A?

    PubMed Central

    Srivastava, Anurita; Datta, Niloy Ranjan

    2014-01-01

    Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy (ICBT) in cancer cervix is based on Tod and Meredith’s point A and has been in practice since 1938. This was proposed at a time when accessibility to imaging technology and dose computation facilities was limited. The concept has been in practice worldwide for more than half a century and has been the fulcrum of all ICBT treatments, strategies and outcome measures. The method is simple and can be adapted by all centres practicing ICBT in cancer cervix. However, with the widespread availability of imaging techniques, clinical use of different dose-rates, availability of a host of applicators fabricated with image compatible materials, radiobiological implications of dose equivalence and its impact on tumour and organs at risk; more and more weight is being laid down on individualised image based brachytherapy. Thus, computed tomography, magnetic-resonance imaging and even positron emission computerized tomography along with brachytherapy treatment planning system are being increasingly adopted with promising outcomes. The present article reviews the evolution of dose prescription concepts in ICBT in cancer cervix and brings forward the need for image based brachytherapy to evaluate clinical outcomes. As is evident, a gradual transition from “point” based brachytherapy to “profile” based image guided brachytherapy is gaining widespread acceptance for dose prescription, reporting and outcome evaluation in the clinical practice of ICBT in cancer cervix. PMID:25302176

  10. Ultra-Wideband Time-Difference-of-Arrival Two-Point-Tracking System

    NASA Technical Reports Server (NTRS)

    Ni, Jianjun David; Arndt, Dickey; Ngo, Phong; Phan, Chau; Dekome, Kent; Dusl, John

    2009-01-01

    A UWB TDOA Two-Point-Tracking System has been conceived and developed at JSC. This system can provide sub-inch tracking capability of two points on one target. This capability can be applied to guide a docking process in a 2D space. Lab tests demonstrate the feasibility of this technology.

  11. Tripled Readout Slices in Multi Time-Point pCASL Using Multiband Look-Locker EPI

    PubMed Central

    Zhang, Ke; Yun, Seong Dae; Shah, N. Jon

    2015-01-01

    Multi time-point pseudo-continuous arterial spin labelling (pCASL) with a Look-Locker EPI readout can sample the signal curve of blood kinetics at multiple time points after the labelling pulse. However, due to signal relaxation of labelled blood, the number of readout slices is limited. The aim of this study is to employ a multiband excitation technique to triple the number of readout slices in multi time-point pCASL. The multiband technique, along with 2-fold in-plane parallel imaging, was incorporated into the Look-Locker EPI for the multi time-point sampling of blood kinetic behaviour following the pCASL labelling scheme. The performance evaluation of the multiband and the single-band techniques were performed on four healthy subjects using a 32-channel head RF coil at 3T. Quantitative perfusion maps were analysed using a combination of labelling with and without flow suppression gradients. The perfusion maps provided by the multiband accelerated multi time-point pCASL were in good agreement with the conventional single-band technique. Multiband acceleration caused SNR loss but offered quantitative perfusion maps in 6.23 min with 18 slices compared with 6 slices within the same time period for the single-band method. As conclusion, the multiband technique can successfully triple the number of readout slices while achieving comparable perfusion data in the same measurement time as the conventional single-band readout. PMID:26544715

  12. Stochastic modelling for biodosimetry: Predicting the chromosomal response to radiation at different time points after exposure

    NASA Astrophysics Data System (ADS)

    Deperas-Standylo, Joanna; Gudowska-Nowak, Ewa; Ritter, Sylvia

    2014-07-01

    Cytogenetic data accumulated from the experiments with peripheral blood lymphocytes exposed to densely ionizing radiation clearly demonstrate that for particles with linear energy transfer (LET) >100 keV/ μm the derived relative biological effectiveness (RBE) will strongly depend on the time point chosen for the analysis. A reasonable prediction of radiation-induced chromosome damage and its distribution among cells can be achieved by exploiting Monte Carlo methodology along with the information about the radius of the penetrating ion-track and the LET of the ion beam. In order to examine the relationship between the track structure and the distribution of aberrations induced in human lymphocytes and to clarify the correlation between delays in the cell cycle progression and the aberration burden visible at the first post-irradiation mitosis, we have analyzed chromosome aberrations in lymphocytes exposed to Fe-ions with LET values of 335 keV/ μm and formulated a Monte Carlo model which reflects time-delay in mitosis of aberrant cells. Within the model the frequency distributions of aberrations among cells follow the pattern of local energy distribution and are well approximated by a time-dependent compound Poisson statistics. The cell-division cycle of undamaged and aberrant cells and chromosome aberrations are modelled as a renewal process represented by a random sum of (independent and identically distributed) random elements S N = ∑ N i=0 X i . Here N stands for the number of particle traversals of cell nucleus, each leading to a statistically independent formation of X i aberrations. The parameter N is itself a random variable and reflects the cell cycle delay of heavily damaged cells. The probability distribution of S N follows a general law for which the moment generating function satisfies the relation Φ S N = Φ N ( Φ X i ). Formulation of the Monte Carlo model which allows to predict expected fluxes of aberrant and non-aberrant cells has been based

  13. New definitions of pointing stability - ac and dc effects. [constant and time-dependent pointing error effects on image sensor performance

    NASA Technical Reports Server (NTRS)

    Lucke, Robert L.; Sirlin, Samuel W.; San Martin, A. M.

    1992-01-01

    For most imaging sensors, a constant (dc) pointing error is unimportant (unless large), but time-dependent (ac) errors degrade performance by either distorting or smearing the image. When properly quantified, the separation of the root-mean-square effects of random line-of-sight motions into dc and ac components can be used to obtain the minimum necessary line-of-sight stability specifications. The relation between stability requirements and sensor resolution is discussed, with a view to improving communication between the data analyst and the control systems engineer.

  14. Radioisotopic Tie Points of the Quaternary Geomagnetic Instability Time Scale (GITS): How Accurate and Precise?

    NASA Astrophysics Data System (ADS)

    Singer, B. S.

    2014-12-01

    Reversals and excursions of the geomagnetic field are recorded globally by sedimentary and volcanic rocks. These geodynamo instabilities provide a rich set of chronostratigraphic tie points for the Quaternary period that can provide tests of age models central to paleoclimate studies. Radioisotopic dating of volcanic rocks, mainly 40Ar/39Ar dating of lava flows, coupled with astronomically-dated deep sea sediments, reveals 10 polarity reversals and 27 field excursions during the Quaternary (Singer, 2014). A key question concerns the uncertainties associated with radioisotopic dates of those geodynamo instabilities that have been identified both in terrestrial volcanic rocks and in deep sea sediments. These particular features offer the highest confidence in linking 40Ar/39Ar dates to the global marine climate record. Geological issues aside, for rocks in which the build-up of 40Ar by decay of 40K may be overwhelmed by atmospheric 40Ar at the time of eruption, the uncertainty in 40Ar/39Ar dates derives from three sources: (1) analytical uncertainty associated with measurement of the isotopes; this is straightforward to estimate; (2) systematic uncertainties stemming from the age of standard minerals, such as the Fish Canyon sanidine, and in the 40K decay constant; and (3) systematic uncertainty introduced during analysis, mainly the size and reproducibility of procedural blanks. Whereas 1 and 2 control the precision of an age determination, 2 and 3 also control accuracy. In parallel with an astronomical calibration of 28.201 Ma for the Fish Canyon sanidine standard, awareness of the importance of procedural blanks, and a new generation multi-collector mass spectrometer capable of exceptionally low-blank and isobar-free analysis, are improving both accuracy and precision of 40Ar/39Ar dates. Results from lavas recording the Matuyama-Brunhes reversal, the Santa Rosa excursion, and the reversal at the top of the Cobb Mtn subchron demonstrate these advances. Current best

  15. Hereditary angioedema: Validation of the end point time to onset of relief by correlation with symptom intensity.

    PubMed

    Bernstein, Jonathan A; Ritchie, Bruce; Levy, Robyn J; Wasserman, Richard L; Bewtra, Againdra K; Hurewitz, David S; Obtułowicz, Krystyna; Reshef, Avner; Moldovan, Dumitru; Shirov, Todor; Grivcheva-Panovska, Vesna; Kiessling, Peter C; Keinecke, Heinz-Otto; Craig, Timothy J

    2011-01-01

    Time to onset of symptom relief in hereditary angioedema (HAE) is a common primary end point in clinical studies but it has never been validated by correlation with the course of HAE symptoms. This study was designed as a retrospective validation of the primary end point for a placebo-controlled phase II/III study in patients with HAE. Ninety-eight abdominal attacks were treated with 10 or 20 U/kg of a highly purified C1 esterase inhibitor (C1-INH) concentrate or placebo. The primary end point was the time to onset of symptom relief, as determined by the patients. Patients assessed the intensity of the symptoms of pain, nausea, vomiting, cramps, and diarrhea over time. By Spearman rank correlation, the primary end point was compared with the time to first reduction of (1) any symptom intensity, (2) the sum of symptom intensity scores, and (3) the intensity of the last symptom present at baseline. The C1-INH, 20 U/kg, and placebo groups were compared by one-sided two-sample Wilcoxon tests. The time to first reduction in intensity of the last symptom present at baseline had the highest correlation with the primary end point (r = 0.77). The time to onset of symptom relief and the time to the first reduction in intensity of the last symptom were significantly shorter for the C1-INH, 20 U/kg, group compared with placebo (p = 0.009 and p = 0.0036, respectively). The association with the intensity of single symptoms confirmed that the time to onset of symptom relief is an appropriate end point for assessing the efficacy of C1-INH therapy. PMID:21262096

  16. Inference of fitness values and putative appearance time points for evolvable self-replicating molecules from time series of occurrence frequencies in an evolution reactor.

    PubMed

    Aita, Takuyo; Ichihashi, Norikazu; Yomo, Tetsuya

    2016-07-21

    We have established a translation-coupled RNA replication system within a cell-like compartment, and conducted an experimental evolution of the RNA molecules in the system. Then, we obtained a time series of occurrence frequencies of 91 individual genotypes through random sampling and next-generation sequencing. The time series showed a complex clonal interference and a polymorphic population called the "quasispecies". By fitting a deterministic kinetic model of evolvable simple self-replicators to the time series, we estimated the fitness value and "putative appearance time point" for each of the 91 major genotypes identified, where the putative appearance time point is defined as a certain time point at which a certain mutant genotype is supposed to appear in the deterministic kinetic model. As a result, the kinetic model was well fitted and additionally we confirmed that the estimated fitness values for 11 genotypes were considerably close to the experimentally measured ones (Ichihashi et al., 2015). In this sequel paper, with the theoretical basis of the deterministic kinetic model, we present the details of inference of the fitness values and putative appearance time points for the 91 genotypes. It may be possible to apply this methodology to other self-replicating molecules, viruses and bacteria. PMID:27091052

  17. FUSING POINT AND AREAL LEVEL SPACE-TIME DATA WITH APPLICATION TO WET DEPOSITION

    EPA Science Inventory

    Motivated by the problem of predicting annual wet chemical deposition in the eastern United States, this paper develops a framework for joint modeling of point and grid referenced spatio-temporal data. The proposed hierarchical model is able to provide accurate spatial interpolat...

  18. Change over Time in First Graders' Strategic Use of Information at Point of Difficulty in Reading

    ERIC Educational Resources Information Center

    McGee, Lea M.; Kim, Hwewon; Nelson, Kathryn S.; Fried, Mary D.

    2015-01-01

    In this study, we describe young students' actions at point of difficulty in reading and examine changes in their strategic use of sources of information. We examined errors from running records of first graders who entered Reading Recovery (RR) in the fall and ended the year reading at the first-grade level compared with RR first graders who did…

  19. Different RAN Components Relate to Reading at Different Points in Time

    ERIC Educational Resources Information Center

    Georgiou, George K.; Papadopoulos, Timothy C.; Kaizer, Eleni L.

    2014-01-01

    The present 10-year longitudinal study examined how rapid automatized naming (RAN) components--articulation time and pause time--relate to reading fluency. Seventy-five Greek-speaking children were followed from Grade 1 to Grade 10 and were assessed five times (in Grades 1, 2, 4, 6, and 10) on RAN (digits and objects) and reading fluency (word…

  20. Real-time 2D floating-point fast Fourier transforms for seeker simulation

    NASA Astrophysics Data System (ADS)

    Chamberlain, Richard; Lord, Eric; Shand, David J.

    2002-07-01

    The floating point Fast Fourier Transform (FFT) is one of the most useful basic functions available to the image and signal processing engineer allowing many complex and detailed special functions to be implemented more simply in the frequency domain. In the Hardware-in-the-Loop field an image transformed using FFT would allow the designer to think about accurate frequency based simulation of seeker lens effects, motion blur, detector transfer functions and much more. Unfortunately, the transform requires many hundreds of thousands or millions of floating point operations on a single modest sized image making it impractical for realtime Hardware-in-the-Loop systems. .until now. This paper outlines the development, by Nallatech, of an FPGA based IEEE floating point core. It traces the subsequent use of this core to develop a full 256 X 256 FFT and filter process implemented on COTS hardware at frame rates up to 150Hz. This transform can be demonstrated to model optical transfer functions at a far greater accuracy than the current spatial models. Other applications and extensions of this technique will be discussed such as filtering for image tracking algorithms and in the simulation of radar processing in the frequency domain.

  1. Real-time GPS sensing of atmospheric water vapor: Precise point positioning with orbit, clock, and phase delay corrections

    NASA Astrophysics Data System (ADS)

    Li, Xingxing; Dick, Galina; Ge, Maorong; Heise, Stefan; Wickert, Jens; Bender, Michael

    2014-05-01

    The recent development of the International Global Navigation Satellite Systems Service Real-Time Pilot Project and the enormous progress in precise point positioning (PPP) techniques provide a promising opportunity for real-time determination of Integrated Water Vapor (IWV) using GPS ground networks for various geodetic and meteorological applications. In this study, we develop a new real-time GPS water vapor processing system based on the PPP ambiguity fixing technique with real-time satellite orbit, clock, and phase delay corrections. We demonstrate the performance of the new real-time water vapor estimates using the currently operationally used near-real-time GPS atmospheric data and collocated microwave radiometer measurements as an independent reference. The results show that an accuracy of 1.0 ~ 2.0 mm is achievable for the new real-time GPS based IWV value. Data of such accuracy might be highly valuable for time-critical geodetic (positioning) and meteorological applications.

  2. The Effects of Part-Time Employment on High School Students' Grade Point Averages and Rate of School Attendance.

    ERIC Educational Resources Information Center

    Heffez, Jack

    To determine what effects employment will have on high school students' grade point averages and rate of school attendance, the author involved fifty-six students in an experiment. Twenty-eight students were employed part-time under the Youth Incentive Entitlement Project (YIEP). The twenty-eight students in the control group were eligible for…

  3. 13 CFR 121.602 - At what point in time must a 8(a) BD applicant be small?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) BD applicant be small? 121.602 Section 121.602 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS SIZE REGULATIONS Size Eligibility Provisions and Standards Size Eligibility Requirements for the 8(a) Business Development Program § 121.602 At what point in time must a 8(a) BD...

  4. 13 CFR 121.602 - At what point in time must a 8(a) BD applicant be small?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) BD applicant be small? 121.602 Section 121.602 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS SIZE REGULATIONS Size Eligibility Provisions and Standards Size Eligibility Requirements for the 8(a) Business Development Program § 121.602 At what point in time must a 8(a) BD...

  5. 13 CFR 121.602 - At what point in time must a 8(a) BD applicant be small?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) BD applicant be small? 121.602 Section 121.602 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS SIZE REGULATIONS Size Eligibility Provisions and Standards Size Eligibility Requirements for the 8(a) Business Development Program § 121.602 At what point in time must a 8(a) BD...

  6. 13 CFR 121.602 - At what point in time must a 8(a) BD applicant be small?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) BD applicant be small? 121.602 Section 121.602 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS SIZE REGULATIONS Size Eligibility Provisions and Standards Size Eligibility Requirements for the 8(a) Business Development Program § 121.602 At what point in time must a 8(a) BD...

  7. 13 CFR 121.602 - At what point in time must a 8(a) BD applicant be small?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) BD applicant be small? 121.602 Section 121.602 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS SIZE REGULATIONS Size Eligibility Provisions and Standards Size Eligibility Requirements for the 8(a) Business Development Program § 121.602 At what point in time must a 8(a) BD...

  8. An Exploratory Investigation of Diffused Point Arrival Time and Source Credibility.

    ERIC Educational Resources Information Center

    Baxter, Leslie A.; Ward, Jean M.

    Because much conjecture (but limited empirical research) exists about the nonverbal variable to time, this exploratory study investigated the effects of differential arrival times on four dimensions of source credibility: sociability, dynamism, competence, and composure. Subjects were 84 educational secretaries with a mean age of 49 years. Each…

  9. The Use and Abuse of Part-Time Faculty: The Part-Timers' Point of View.

    ERIC Educational Resources Information Center

    Wilson, Wendy L.

    Problems faced by part-time faculty members are identified, and suggestions to avoid mistreatment of these teachers are offered. Disadvantages of part-time teaching include the lack of equitable pay and benefits. Since most institutions have a standard pay rate for part-timers, it is suggested that teaching excellence be recognized by creating…

  10. Point process time-frequency analysis of respiratory sinus arrhythmia under altered respiration dynamics.

    PubMed

    Kodituwakku, Sandun; Lazar, Sara W; Indic, Premananda; Brown, Emery N; Barbieri, Riccardo

    2010-01-01

    Respiratory sinus arrhythmia (RSA) is largely mediated by the autonomic nervous system through its modulating influence on the heartbeat. We propose an algorithm for quantifying instantaneous RSA as applied to heart beat interval and respiratory recordings under dynamic respiration conditions. The blood volume pressure derived heart beat series (pulse intervals, PI) are modeled as an inverse gaussian point process, with the instantaneous mean PI modeled as a bivariate regression incorporating both past PI and respiration values observed at the beats. A point process maximum likelihood algorithm is used to estimate the model parameters, and instantaneous RSA is estimated by a frequency domain transfer function approach. The model is statistically validated using Kolmogorov-Smirnov (KS) goodness-of-fit analysis, as well as independence tests. The algorithm is applied to subjects engaged in meditative practice, with distinctive dynamics in the respiration patterns elicited as a result. Experimental results confirm the ability of the algorithm to track important changes in cardiorespiratory interactions elicited during meditation, otherwise not evidenced in control resting states. PMID:21096135

  11. Point process time-frequency analysis of dynamic respiratory patterns during meditation practice.

    PubMed

    Kodituwakku, Sandun; Lazar, Sara W; Indic, Premananda; Chen, Zhe; Brown, Emery N; Barbieri, Riccardo

    2012-03-01

    Respiratory sinus arrhythmia (RSA) is largely mediated by the autonomic nervous system through its modulating influence on the heart beats. We propose a robust algorithm for quantifying instantaneous RSA as applied to heart beat intervals and respiratory recordings under dynamic breathing patterns. The blood volume pressure-derived heart beat series (pulse intervals, PIs) are modeled as an inverse Gaussian point process, with the instantaneous mean PI modeled as a bivariate regression incorporating both past PIs and respiration values observed at the beats. A point process maximum likelihood algorithm is used to estimate the model parameters, and instantaneous RSA is estimated via a frequency domain transfer function evaluated at instantaneous respiratory frequency where high coherence between respiration and PIs is observed. The model is statistically validated using Kolmogorov-Smirnov goodness-of-fit analysis, as well as independence tests. The algorithm is applied to subjects engaged in meditative practice, with distinctive dynamics in the respiration patterns elicited as a result. The presented analysis confirms the ability of the algorithm to track important changes in cardiorespiratory interactions elicited during meditation, otherwise not evidenced in control resting states, reporting statistically significant increase in RSA gain as measured by our paradigm. PMID:22350435

  12. A hierarchical model combining distance sampling and time removal to estimate detection probability during avian point counts

    USGS Publications Warehouse

    Amundson, Courtney L.; Royle, J. Andrew; Handel, Colleen M.

    2014-01-01

    Imperfect detection during animal surveys biases estimates of abundance and can lead to improper conclusions regarding distribution and population trends. Farnsworth et al. (2005) developed a combined distance-sampling and time-removal model for point-transect surveys that addresses both availability (the probability that an animal is available for detection; e.g., that a bird sings) and perceptibility (the probability that an observer detects an animal, given that it is available for detection). We developed a hierarchical extension of the combined model that provides an integrated analysis framework for a collection of survey points at which both distance from the observer and time of initial detection are recorded. Implemented in a Bayesian framework, this extension facilitates evaluating covariates on abundance and detection probability, incorporating excess zero counts (i.e. zero-inflation), accounting for spatial autocorrelation, and estimating population density. Species-specific characteristics, such as behavioral displays and territorial dispersion, may lead to different patterns of availability and perceptibility, which may, in turn, influence the performance of such hierarchical models. Therefore, we first test our proposed model using simulated data under different scenarios of availability and perceptibility. We then illustrate its performance with empirical point-transect data for a songbird that consistently produces loud, frequent, primarily auditory signals, the Golden-crowned Sparrow (Zonotrichia atricapilla); and for 2 ptarmigan species (Lagopus spp.) that produce more intermittent, subtle, and primarily visual cues. Data were collected by multiple observers along point transects across a broad landscape in southwest Alaska, so we evaluated point-level covariates on perceptibility (observer and habitat), availability (date within season and time of day), and abundance (habitat, elevation, and slope), and included a nested point

  13. A new universal equation for the time of transfer between two points of the central gravitational field

    NASA Astrophysics Data System (ADS)

    Burdaev, M. N.

    2011-10-01

    The paper presents the derivation of two new equations for calculating the time of transfer between two points of the central gravitational field: for hyperbolic orbits and the universal equation for elliptical and hyperbolic orbits. In the paper we have used as an independent variable, instead of the linear elements (semimajor axis, focal parameter of orbit or a chord connecting the ends of boundary radii of transfer), the angular parameter—the angle between the radius vector of an initial point of transfer and the vector of initial velocity of transfer. Paper's material is a continuation of that presented in the "Space research" Journal, vol. 2, March-April, 2009.

  14. Atmospheric plume progression as a function of time and distance from the release point for radioactive isotopes

    SciTech Connect

    Eslinger, Paul W.; Bowyer, Ted W.; Cameron, Ian M.; Hayes, James C.; Miley, Harry S.

    2015-10-01

    The International Monitoring System contains up to 80 stations around the world that have aerosol and xenon monitoring systems designed to detect releases of radioactive materials to the atmosphere from nuclear tests. A rule of thumb description of plume concentration and duration versus time and distance from the release point is useful when designing and deploying new sample collection systems. This paper uses plume development from atmospheric transport modeling to provide a power-law rule describing atmospheric dilution factors as a function of distance from the release point.

  15. Timing readout in paper device for quantitative point-of-use hemin/G-quadruplex DNAzyme-based bioassays.

    PubMed

    Zhang, Yun; Fan, Jinlong; Nie, Jinfang; Le, Shangwang; Zhu, Wenyuan; Gao, Dong; Yang, Jiani; Zhang, Songbai; Li, Jianping

    2015-11-15

    This work describes a quantitative point-of-use hemin/G-quadruplex DNAzyme-based assay that integrates a simple timing detection motif with low-cost, portable microfluidic paper-based analytical devices (μPADs). The timing readout is based on the selective DNAzyme-mediated wettability change of paper from hydrophilicity to hydrophobicity. Its utility is well demonstrated with sensitive, specific detection of K(+) ion as a model analyte in artificial samples as well as real human serum samples. This new method only requires a ubiquitous cheap timer (or a cell phone with a timing function) to provide quantitative results. It could offer new opportunities for the development of more peroxidase-mimicking DNAzyme-based bioassays that are simple, affordable, portable, and operable by minimally-trained users for broad point-of-use applications especially in resource-poor settings. PMID:26042873

  16. Grayscale image segmentation for real-time traffic sign recognition: the hardware point of view

    NASA Astrophysics Data System (ADS)

    Cao, Tam P.; Deng, Guang; Elton, Darrell

    2009-02-01

    In this paper, we study several grayscale-based image segmentation methods for real-time road sign recognition applications on an FPGA hardware platform. The performance of different image segmentation algorithms in different lighting conditions are initially compared using PC simulation. Based on these results and analysis, suitable algorithms are implemented and tested on a real-time FPGA speed sign detection system. Experimental results show that the system using segmented images uses significantly less hardware resources on an FPGA while maintaining comparable system's performance. The system is capable of processing 60 live video frames per second.

  17. A key time point for cell growth and magnetosome synthesis of Magnetospirillum gryphiswaldense based on real-time analysis of physiological factors

    PubMed Central

    Yang, Jing; Li, Shuqi; Huang, Xiuliang; Tang, Tao; Jiang, Weizhong; Zhang, Tongwei; Li, Ying

    2013-01-01

    Pure culture of magnetotactic bacteria with high magnetosome yield has been achieved for only a few strains. The major obstacles involve the nutritional requirements and culture conditions of the cells. To increase cell density and magnetosome production, it is necessary to elucidate the physiological characteristics of a particular strain during cell growth and develop an appropriate artificial control strategy. Large-scale culture of Magnetospirillum gryphiswaldense strain MSR-1 was successfully performed for 48 h in a 42-L autofermentor, and several key physiological parameters were measured in real time. Maximal values of cell density (OD565) (19.4) and cell yield (dry weight) (4.76 g/L) were attained at 40 h. The key time point for cell growth and magnetosome formation was found to be 18–20 h. At this point, cells entered the log phase of growth, the maximal values of Cmag (1.78), iron content (0.47%), and magnetosome number (26 ± 3 per cell) were observed, superoxide dismutase (SOD) activity began to decrease more rapidly, ATP content dropped to an extremely low level (0.17 fmol), and reducing power (NADH/NAD+ ratio) began to increase very rapidly. Excessive levels of dissolved oxygen (≥20 ppb) and lactic acid in the medium caused notable cytotoxic effects after 20 h. Artificial control measures for fermentation must be based on realistic cell physiological conditions. At the key time point (18–20 h), cell density is high and magnetosomes have matured. The process of magnetosome synthesis involves a high consumption of ATP and reducing power, and the cells require replenishment of nutrients prior to the 18–20 h time point. Culture conditions that effectively minimize dissolved oxygen accumulation, lactic acid content, and reducing power at this point will enhance magnetosome yield without obvious inhibition of cell growth. PMID:23898327

  18. Grade Point Average as a Predictor of Timely Graduation from Associate Degree Registered Nursing Programs

    ERIC Educational Resources Information Center

    Jackson, Delores J.

    2010-01-01

    The purpose of this study was to determine if admission selection strategies that utilize cumulative and/or pre-requisite GPA are predictive of timely graduation for associate degree nursing (RN-AD) students. Data were obtained from de-identified records of 437 associate degree nursing students enrolled in three Midwest community colleges from…

  19. The cryptococcal antigen lateral flow assay: A point-of-care diagnostic at an opportune time.

    PubMed

    Tang, Michele W; Clemons, Karl V; Katzenstein, David A; Stevens, David A

    2016-08-01

    Cryptococcal meningitis is a devastating HIV-related opportunistic infection, affecting nearly 1 million individuals and causing over 500 000 deaths each year. The burden of disease is greatest in sub-Saharan Africa and Southeast Asia, where cryptococcal disease is the most common cause of meningitis. Rapid, accurate and affordable diagnosis of cryptococcal disease has been lacking in many of the most heavily affected areas. Here, we review a point-of-care assay for cryptococcal disease, the dipstick-formatted cryptococcal antigen lateral flow assay (LFA) (IMMY, Norman, OK). In comparison to culture, the assay is 99.5% sensitive and 98% specific. In comparison to other commercially available tests for cryptococcal antigen, the LFA has equal or superior sensitivity and specificity in CSF, plasma and serum samples. We discuss potential applications for the use of the assay in resource-limited settings, including what is likely to be an important role of the LFA in screening for early cryptococcal infection before clinical disease and in evaluating pre-emptive treatment. PMID:25612826

  20. [Forestalling policy as a strategic objective of space biology and medicine at the present time point].

    PubMed

    Ushakov, I B

    2011-01-01

    The article ushers into the acrimonious debates about paths of innovative development and criticality of fundamental sciences in technological progress for Russia security, and breakthrough potential. Among the alternative routes of technical development are different forms of priority boost of growing points in which Russia has attained and held steadily the leading position occupying a prominent segment in the international division of labor. Space effort of Russia gives a model example of successful implementation of the national program and demonstrates leadership in this area of human activities. The article presents analysis of the factors and circumstances that predetermined the winning in the early, Gagarin's period of piloted space flights of the forefront position of the country as well as the vector of cosmonautics' advance for many years ahead Despite the host of issues with implementation of the ISS utilization program and planning of exploration missions to the Moon and Mars, the unique experience of preparations and carrying out investigations and tests with humans in space, the enormous groundwork in fundamental biomedical researches over the past 50 years of piloted flights allow optimistic prognosis of gaining headway with essentially new ambitious space projects. The key question is whether the forestalling policy of priority development of piloted cosmonautics as the most integrated and science intensive sector of innovation techniques will be realized. The answer will guide near- and long-term future of the space industry and, consequently, the fortune of national fundamental space sciences, space biomedicine being its part and parcel. PMID:21675188

  1. [Multiple time scales analysis of spatial differentiation characteristics of non-point source nitrogen loss within watershed].

    PubMed

    Liu, Mei-bing; Chen, Xing-wei; Chen, Ying

    2015-07-01

    Identification of the critical source areas of non-point source pollution is an important means to control the non-point source pollution within the watershed. In order to further reveal the impact of multiple time scales on the spatial differentiation characteristics of non-point source nitrogen loss, a SWAT model of Shanmei Reservoir watershed was developed. Based on the simulation of total nitrogen (TN) loss intensity of all 38 subbasins, spatial distribution characteristics of nitrogen loss and critical source areas were analyzed at three time scales of yearly average, monthly average and rainstorms flood process, respectively. Furthermore, multiple linear correlation analysis was conducted to analyze the contribution of natural environment and anthropogenic disturbance on nitrogen loss. The results showed that there were significant spatial differences of TN loss in Shanmei Reservoir watershed at different time scales, and the spatial differentiation degree of nitrogen loss was in the order of monthly average > yearly average > rainstorms flood process. TN loss load mainly came from upland Taoxi subbasin, which was identified as the critical source area. At different time scales, land use types (such as farmland and forest) were always the dominant factor affecting the spatial distribution of nitrogen loss, while the effect of precipitation and runoff on the nitrogen loss was only taken in no fertilization month and several processes of storm flood at no fertilization date. This was mainly due to the significant spatial variation of land use and fertilization, as well as the low spatial variability of precipitation and runoff. PMID:26710649

  2. Joint transfer of time and frequency signals and multi-point synchronization via fiber network

    NASA Astrophysics Data System (ADS)

    Nan, Cheng; Wei, Chen; Qin, Liu; Dan, Xu; Fei, Yang; You-Zhen, Gui; Hai-Wen, Cai

    2016-01-01

    A system of jointly transferring time signals with a rate of 1 pulse per second (PPS) and frequency signals of 10 MHz via a dense wavelength division multiplex-based (DWDM) fiber is demonstrated in this paper. The noises of the fiber links are suppressed and compensated for by a controlled fiber delay line. A method of calibrating and characterizing time is described. The 1PPS is synchronized by feed-forward calibrating the fiber delays precisely. The system is experimentally examined via a 110 km spooled fiber in laboratory. The frequency stabilities of the user end with compensation are 1.8×10-14 at 1 s and 2.0×10-17 at 104 s average time. The calculated uncertainty of time synchronization is 13.1 ps, whereas the direct measurement of the uncertainty is 12 ps. Next, the frequency and 1PPS are transferred via a metropolitan area optical fiber network from one central site to two remote sites with distances of 14 km and 110 km. The frequency stabilities of 14 km link reach 3.0×10-14 averaged in 1 s and 1.4×10-17 in 104 s respectively; and the stabilities of 110 km link are 8.3×10-14 and 1.7×10-17, respectively. The accuracies of synchronization are estimated to be 12.3 ps for the 14 km link and 13.1 ps for the 110 km link, respectively. Project supported by the National Natural Science Foundation of China (Grant No. 61405227).

  3. Real-Time Point Positioning Performance Evaluation of Single-Frequency Receivers Using NASA's Global Differential GPS System

    NASA Technical Reports Server (NTRS)

    Muellerschoen, Ronald J.; Iijima, Byron; Meyer, Robert; Bar-Sever, Yoaz; Accad, Elie

    2004-01-01

    This paper evaluates the performance of a single-frequency receiver using the 1-Hz differential corrections as provided by NASA's global differential GPS system. While the dual-frequency user has the ability to eliminate the ionosphere error by taking a linear combination of observables, the single-frequency user must remove or calibrate this error by other means. To remove the ionosphere error we take advantage of the fact that the magnitude of the group delay in range observable and the carrier phase advance have the same magnitude but are opposite in sign. A way to calibrate this error is to use a real-time database of grid points computed by JPL's RTI (Real-Time Ionosphere) software. In both cases we evaluate the positional accuracy of a kinematic carrier phase based point positioning method on a global extent.

  4. A material point time integration procedure for anisotropic, thermo rheologically simple, viscoelastic solids

    NASA Astrophysics Data System (ADS)

    Poon, H.; Ahmad, M. F.

    This study presents an effective and robust time integration procedure for general anisotropic, thermal rheologically simple viscoelasticity, that is suitable for implementation in a broad spectrum of general purpose nonlinear finite element programs. It features a judicious choice of state variables which record the extent of inelastic flow (creep), a stable backward Euler integration step, and a consistent tangent operator. Numerical examples involving homogeneous stress states such as uniaxial tension and simple shear, and non-uniform stress states such as a beam under tip load, were carried out by incorporating the present scheme into a general purpose FEM package. Excellent agreement with analytical results is observed.

  5. Solar glare hazard analysis tool on account of determined points of time

    DOEpatents

    Ho, Clifford K; Sims, Cianan Alexander

    2014-09-23

    Technologies pertaining to determining when glare will be perceived by a hypothetical observer from a glare source and the intensity of glare that will be perceived by the hypothetical observer from the glare source are described herein. A first location of a potential source of solar glare is received, and a second location of the hypothetical observer is received. Based upon such locations, including respective elevations, and known positions of the sun over time, a determination as to when the hypothetical observer will perceive glare from the potential source of solar glare is made. Subsequently, an amount of irradiance entering the eye of the hypothetical observer is calculated to assess potential ocular hazards.

  6. Self-action of a point charge in a wormhole space-time

    SciTech Connect

    Khusnutdinov, Nail R.; Bakhmatov, Ilya V.

    2007-12-15

    We consider the self-energy and the self-force for an electrically charged particle at rest in the wormhole space-time. We develop a general approach to finding the self-force and apply it to the two specific profiles of the wormhole throat with singular and with smooth curvature. The self-force for these two profiles is found in manifest form; it turns out to be an attractive force. We also find an expression for the self-force in the case of arbitrary symmetric throat profile. Far from the throat the self-force is always attractive.

  7. The relative timing between eye and hand in rapid sequential pointing is affected by time pressure, but not by advance knowledge.

    PubMed

    Deconinck, F J A; van Polanen, V; Savelsbergh, G J P; Bennett, S J

    2011-08-01

    The present study examined the effect of timing constraints and advance knowledge on eye-hand coordination strategy in a sequential pointing task. Participants were required to point at two successively appearing targets on a screen while the inter-stimulus interval (ISI) and the trial order were manipulated, such that timing constraints were high (ISI = 300 ms) or low (ISI = 450 ms) and advance knowledge of the target location was present (fixed order) or absent (random order). Analysis of eye and finger onset and completion times per segment of the sequence indicated that oculo-manual behaviour was in general characterized by eye movements preceding the finger, as well as 'gaze anchoring' (i.e. eye fixation of the first target until completion of the finger movement towards that target). Advance knowledge of future target locations lead to shorter latency times of eye and hand, and smaller eye-hand lead times, which in combination resulted in shorter total movement times. There was, however, no effect of advance knowledge on the duration of gaze anchoring. In contrast, gaze anchoring did change as a function of the interval between successive stimuli and was shorter with a 300 ms ISI versus 450 ms ISI. Further correlation analysis provided some indication that shorter residual latency is associated with shorter pointing duration, without affecting accuracy. These results are consistent with a neural mechanism governing the coupling of eye and arm movements, which has been suggested to reside in the superior colliculus. The temporal coordination resulting from this coupling is a function of the time pressure on the visuo-manual system resulting from the appearance of external stimuli. PMID:21744087

  8. An engineering time-domain model for curve squeal: Tangential point-contact model and Green's functions approach

    NASA Astrophysics Data System (ADS)

    Zenzerovic, I.; Kropp, W.; Pieringer, A.

    2016-08-01

    Curve squeal is a strong tonal sound that may arise when a railway vehicle negotiates a tight curve. In contrast to frequency-domain models, time-domain models are able to capture the nonlinear and transient nature of curve squeal. However, these models are computationally expensive due to requirements for fine spatial and time discretization. In this paper, a computationally efficient engineering model for curve squeal in the time-domain is proposed. It is based on a steady-state point-contact model for the tangential wheel/rail contact and a Green's functions approach for wheel and rail dynamics. The squeal model also includes a simple model of sound radiation from the railway wheel from the literature. A validation of the tangential point-contact model against Kalker's transient variational contact model reveals that the point-contact model performs well within the squeal model up to at least 5 kHz. The proposed squeal model is applied to investigate the influence of lateral creepage, friction and wheel/rail contact position on squeal occurrence and amplitude. The study indicates a significant influence of the wheel/rail contact position on squeal frequencies and amplitudes. Friction and lateral creepage show an influence on squeal occurrence and amplitudes, but this is only secondary to the influence of the contact position.

  9. Specific inhibition of nitric oxide synthases at different time points in a murine model of pulmonary sepsis.

    PubMed

    Lange, Matthias; Hamahata, Atsumori; Traber, Daniel L; Nakano, Yoshimitsu; Traber, Lillian D; Enkhbaatar, Perenlei

    2011-01-21

    Excessive production of nitric oxide (NO) by NO synthase (NOS) and a subsequent oxidative stress reaction are thought to be critically involved in the pathophysiology of sepsis. Previous studies suggested that NO production by neuronal NOS (nNOS) and inducible NOS (iNOS) is implemented in the disease process at different time points after the injury. Here we tested the roles of selective pharmacological inhibition of nNOS and iNOS at different time points in a murine model of pulmonary sepsis. The injury was induced by intranasal administration of live Pseudomonas aeruginosa (3.2×10(7) colony-forming units) in C57BL/6 wild-type mice. The animals received no treatment (control) or treatment with a specific nNOS inhibitor (4 or 8h), iNOS inhibitor (4 or 8h), or non-specific NOS inhibitor (4 or 8h). In controls, the injury was associated with excessive releases of pro-inflammatory cytokines in the plasma, enhanced tissue lipid peroxidation, and decreased survival. Non-specific NOS inhibition at either time point did not influence survival and was not further investigated. While nNOS inhibition at 4h was associated with a trend toward improved survival and significantly reduced contents of lung nitrite/nitrate (NO(x)) and liver malondialdehyde, the blockade of nNOS at 8h had no effect on these parameters. In contrast, early iNOS inhibition was associated with a trend toward decreased survival and no effects on lung NO(x) and liver malondialdehyde contents, whereas later iNOS blockade was associated with decreased malondialdehyde content in liver homogenates. In conclusion, pulmonary sepsis in mice may be beneficially influenced by specific pharmacological nNOS inhibition at an earlier time point and iNOS inhibition at a later time points post-injury. Future investigations should identify the time changes of the expression and activation of NOS isoforms. PMID:21184738

  10. Instantaneous and time-averaged dispersion and measurement models for estimation theory applications with elevated point source plumes

    NASA Technical Reports Server (NTRS)

    Diamante, J. M.; Englar, T. S., Jr.; Jazwinski, A. H.

    1977-01-01

    Estimation theory, which originated in guidance and control research, is applied to the analysis of air quality measurements and atmospheric dispersion models to provide reliable area-wide air quality estimates. A method for low dimensional modeling (in terms of the estimation state vector) of the instantaneous and time-average pollutant distributions is discussed. In particular, the fluctuating plume model of Gifford (1959) is extended to provide an expression for the instantaneous concentration due to an elevated point source. Individual models are also developed for all parameters in the instantaneous and the time-average plume equations, including the stochastic properties of the instantaneous fluctuating plume.

  11. Multiple Time Courses of Vestibular Set-Point Adaptation Revealed by Sustained Magnetic Field Stimulation of the Labyrinth.

    PubMed

    Jareonsettasin, Prem; Otero-Millan, Jorge; Ward, Bryan K; Roberts, Dale C; Schubert, Michael C; Zee, David S

    2016-05-23

    A major focus in neurobiology is how the brain adapts its motor behavior to changes in its internal and external environments [1, 2]. Much is known about adaptively optimizing the amplitude and direction of eye and limb movements, for example, but little is known about another essential form of learning, "set-point" adaptation. Set-point adaptation balances tonic activity so that reciprocally acting, agonist and antagonist muscles have a stable platform from which to launch accurate movements. Here, we use the vestibulo-ocular reflex-a simple behavior that stabilizes the position of the eye while the head is moving-to investigate how tonic activity is adapted toward a new set point to prevent eye drift when the head is still [3, 4]. Set-point adaptation was elicited with magneto-hydrodynamic vestibular stimulation (MVS) by placing normal humans in a 7T MRI for 90 min. MVS is ideal for prolonged labyrinthine activation because it mimics constant head acceleration and induces a sustained nystagmus similar to natural vestibular lesions [5, 6]. The MVS-induced nystagmus diminished slowly but incompletely over multiple timescales. We propose a new adaptation hypothesis, using a cascade of imperfect mathematical integrators, that reproduces the response to MVS (and more natural chair rotations), including the gradual decrease in nystagmus as the set point changes over progressively longer time courses. MVS set-point adaptation is a biological model with applications to basic neurophysiological research into all types of movements [7], functional brain imaging [8], and treatment of vestibular and higher-level attentional disorders by introducing new biases to counteract pathological ones [9]. PMID:27185559

  12. Real-time resolution of point mutations that cause phenovariance in mice

    PubMed Central

    Wang, Tao; Zhan, Xiaowei; Bu, Chun-Hui; Lyon, Stephen; Pratt, David; Hildebrand, Sara; Choi, Jin Huk; Zhang, Zhao; Zeng, Ming; Wang, Kuan-wen; Turer, Emre; Chen, Zhe; Zhang, Duanwu; Yue, Tao; Wang, Ying; Shi, Hexin; Wang, Jianhui; Sun, Lei; SoRelle, Jeff; McAlpine, William; Hutchins, Noelle; Zhan, Xiaoming; Fina, Maggy; Gobert, Rochelle; Quan, Jiexia; Kreutzer, McKensie; Arnett, Stephanie; Hawkins, Kimberly; Leach, Ashley; Tate, Christopher; Daniel, Chad; Reyna, Carlos; Prince, Lauren; Davis, Sheila; Purrington, Joel; Bearden, Rick; Weatherly, Jennifer; White, Danielle; Russell, Jamie; Sun, Qihua; Tang, Miao; Li, Xiaohong; Scott, Lindsay; Moresco, Eva Marie Y.; McInerney, Gerald M.; Karlsson Hedestam, Gunilla B.; Xie, Yang; Beutler, Bruce

    2015-01-01

    With the wide availability of massively parallel sequencing technologies, genetic mapping has become the rate limiting step in mammalian forward genetics. Here we introduce a method for real-time identification of N-ethyl-N-nitrosourea-induced mutations that cause phenotypes in mice. All mutations are identified by whole exome G1 progenitor sequencing and their zygosity is established in G2/G3 mice before phenotypic assessment. Quantitative and qualitative traits, including lethal effects, in single or multiple combined pedigrees are then analyzed with Linkage Analyzer, a software program that detects significant linkage between individual mutations and aberrant phenotypic scores and presents processed data as Manhattan plots. As multiple alleles of genes are acquired through mutagenesis, pooled “superpedigrees” are created to analyze the effects. Our method is distinguished from conventional forward genetic methods because it permits (1) unbiased declaration of mappable phenotypes, including those that are incompletely penetrant (2), automated identification of causative mutations concurrent with phenotypic screening, without the need to outcross mutant mice to another strain and backcross them, and (3) exclusion of genes not involved in phenotypes of interest. We validated our approach and Linkage Analyzer for the identification of 47 mutations in 45 previously known genes causative for adaptive immune phenotypes; our analysis also implicated 474 genes not previously associated with immune function. The method described here permits forward genetic analysis in mice, limited only by the rates of mutant production and screening. PMID:25605905

  13. Real-time resolution of point mutations that cause phenovariance in mice.

    PubMed

    Wang, Tao; Zhan, Xiaowei; Bu, Chun-Hui; Lyon, Stephen; Pratt, David; Hildebrand, Sara; Choi, Jin Huk; Zhang, Zhao; Zeng, Ming; Wang, Kuan-wen; Turer, Emre; Chen, Zhe; Zhang, Duanwu; Yue, Tao; Wang, Ying; Shi, Hexin; Wang, Jianhui; Sun, Lei; SoRelle, Jeff; McAlpine, William; Hutchins, Noelle; Zhan, Xiaoming; Fina, Maggy; Gobert, Rochelle; Quan, Jiexia; Kreutzer, McKensie; Arnett, Stephanie; Hawkins, Kimberly; Leach, Ashley; Tate, Christopher; Daniel, Chad; Reyna, Carlos; Prince, Lauren; Davis, Sheila; Purrington, Joel; Bearden, Rick; Weatherly, Jennifer; White, Danielle; Russell, Jamie; Sun, Qihua; Tang, Miao; Li, Xiaohong; Scott, Lindsay; Moresco, Eva Marie Y; McInerney, Gerald M; Karlsson Hedestam, Gunilla B; Xie, Yang; Beutler, Bruce

    2015-02-01

    With the wide availability of massively parallel sequencing technologies, genetic mapping has become the rate limiting step in mammalian forward genetics. Here we introduce a method for real-time identification of N-ethyl-N-nitrosourea-induced mutations that cause phenotypes in mice. All mutations are identified by whole exome G1 progenitor sequencing and their zygosity is established in G2/G3 mice before phenotypic assessment. Quantitative and qualitative traits, including lethal effects, in single or multiple combined pedigrees are then analyzed with Linkage Analyzer, a software program that detects significant linkage between individual mutations and aberrant phenotypic scores and presents processed data as Manhattan plots. As multiple alleles of genes are acquired through mutagenesis, pooled "superpedigrees" are created to analyze the effects. Our method is distinguished from conventional forward genetic methods because it permits (1) unbiased declaration of mappable phenotypes, including those that are incompletely penetrant (2), automated identification of causative mutations concurrent with phenotypic screening, without the need to outcross mutant mice to another strain and backcross them, and (3) exclusion of genes not involved in phenotypes of interest. We validated our approach and Linkage Analyzer for the identification of 47 mutations in 45 previously known genes causative for adaptive immune phenotypes; our analysis also implicated 474 genes not previously associated with immune function. The method described here permits forward genetic analysis in mice, limited only by the rates of mutant production and screening. PMID:25605905

  14. Regulation of intracellular Zn homeostasis in two intestinal epithelial cell models at various maturation time points.

    PubMed

    Gefeller, Eva-Maria; Bondzio, Angelika; Aschenbach, Jörg R; Martens, Holger; Einspanier, Ralf; Scharfen, Franziska; Zentek, Jürgen; Pieper, Robert; Lodemann, Ulrike

    2015-07-01

    After weaning, piglets are often fed diets supplemented with high concentrations of zinc (Zn) to decrease post-weaning diarrhea. The aim of this study was to elucidate the regulation of Zn homeostasis within intestinal epithelial cells during excessive Zn exposure. High Zn concentrations elevated the intracellular Zn level in IPEC-J2 and Caco-2 cells which was influenced by differentiation status and time of exposure. With increasing Zn concentrations, mRNA and protein levels of metallothionein (MT) and zinc transporter 1 (ZnT1) were upregulated, whereas zinc transporter 4 (ZIP4) expression was downregulated. Metal-regulatory transcription factor-1 (MTF1) mRNA expression was upregulated at high Zn concentrations in IPEC-J2 cells, which corresponded to higher intracellular Zn concentrations. Based on these results, we suggest that intestinal epithelial cells adapt the expression of these genes to the amount of extracellular Zn available in order to maintain Zn homeostasis. Cell line-dependent differences in the regulation of Zn homeostasis were detected. PMID:25757458

  15. Station-keeping of real Earth-Moon libration point orbits using discrete-time sliding mode control

    NASA Astrophysics Data System (ADS)

    Lian, Yijun; Gómez, Gerard; Masdemont, Josep J.; Tang, Guojian

    2014-10-01

    In this work, station-keeping of real Earth-Moon libration point orbits is studied using discrete-time sliding mode control (DSMC). For comparison, a discrete linear quadratic regulator (DLQR) controller is also considered. The libration orbits are termed “real” in the sense that they are obtained in a complete Solar System model, taking into account all the gravitational forces of the planets, the Moon, and the Sun. This is a key point for any station-keeping study, that the use of far from real orbits as nominal ones increases unnecessarily the station-keeping cost. The resulting controlled system, linearised with respect to some nominal orbit, takes a discrete-time form suitable for applying impulsive maneuvers. The DSMC controller is designed by the reaching law with the parameters chosen in an adaptive way. A method for designing the sliding surface is proposed. In order to assess and compare the performance of the two controllers, simulations are done for six libration point orbits around the L2 point (three halo orbits and three Lissajous ones) during a time span of 10 years. Several practical constraints are also considered in the simulations. Extensive Monte Carlo results show that the proposed DSMC approach is able to maintain the spacecraft within a close vicinity of the nominal orbits with a maneuver cost less than 2 m/s per year, and it outperforms the DLQR approach in terms of the position controllability. Some comparison with previous results obtained by other authors with different procedures is also given.

  16. Real time, TV-based, point-image quantizer and sorter

    DOEpatents

    Case, Arthur L.; Davidson, Jackson B.

    1976-01-01

    A device is provided for improving the vertical resolution in a television-based, two-dimensional readout for radiation detection systems such as are used to determine the location of light or nuclear radiation impinging a target area viewed by a television camera, where it is desired to store the data indicative of the centroid location of such images. In the example embodiment, impinging nuclear radiation detected in the form of a scintillation occurring in a crystal is stored as a charge image on a television camera tube target. The target is scanned in a raster and the image position is stored according to a corresponding vertical scan number and horizontal position number along the scan. To determine the centroid location of an image that may overlap a number of horizontal scan lines along the vertical axis of the raster, digital logic circuits are provided with at least four series-connected shift registers, each having 512 bit positions according to a selected 512 horizontal increment of resolutions along a scan line. The registers are shifted by clock pulses at a rate of 512 pulses per scan line. When an image or portion thereof is detected along a scan, its horizontal center location is determined and the present front bit is set in the first shift register and shifted through the registers one at a time for each horizontal scan. Each register is compared bit-by-bit with the preceding register to detect coincident set bit positions until the last scan line detecting a portion of the image is determined. Depending on the number of shift registers through which the first detection of the image is shifted, circuitry is provided to store the vertical center position of the event according to the number of shift registers through which the first detection of the event is shifted. Interpolation circuitry is provided to determine if the event centroid is between adjacent scan lines and stored in a vertical address accordingly. The horizontal location of the event

  17. PROOF OF CONCEPT DEMONSTRATION FOR NEAR REAL-TIME IN SITU DETECTION OF FECAL CONTAMINATION IN FRESH AND MARINE WATERS

    EPA Science Inventory

    A key component of monitoring is the detection and timely reporting of concentrations of bacteria that are associated with human gastroenteritis and indicate fecal contamination. Current monitoring methods require incubation periods between 24 hours and 3 days before public heal...

  18. An Efficient Real-Time Precise Point Positioning (RT-PPP) Solution for Offshore Surveys in Turkey

    NASA Astrophysics Data System (ADS)

    Abdelazeem, Mohamed; Nurhan Çelik, Rahmi

    2016-07-01

    Recently, the international global navigation satellite systems (GNSS) service (IGS) has launched the real-time service (IGS-RTS). The IGS-RTS has shown promise accuracy in precise point positioning applications. Currently, the precise point positioning technique is used extensively in marine applications. In this study, we evaluate the accuracy of the real-time precise point positioning (RT-PPP) solution using the IGS-RTS for offshore surveys in Turkey. Dual-frequency GPS data is collected onboard a vessel and then processed using the Bernese 5.2 PPP module. The IGS-RTS precise orbit and clock products are used in order to account for the satellite orbit and clock products. To investigate the accuracy of the RT-PPP technique, the positioning accuracy is assessed and compared with the traditional double-difference solution. It is shown that the RT-PPP solution has good agreement with the double-difference solution. Also, the proposed solution efficiently fulfills the international maritime organization (IMO) standards for the offshore surveys.

  19. The 24-Hour Job Machine: Computerized Applicant Systems.

    ERIC Educational Resources Information Center

    Wiedman, Lisa W.

    1986-01-01

    The evolution of computerized job applicant systems is described and compared to that of computerized banking systems; the characteristics of such systems in the future, especially for minimizing data entry and maximizing accessibility, are then outlined and illustrated with the Carnegie-Mellon University system. (MSE)

  20. Collection of a 24-Hour Urine Specimen (Beyond the Basics)

    MedlinePlus

    ... the Licensed Materials from any location via the Internet. b. STANDALONE WORKSTATION: A standalone subscription permits multiple ... computer. A Standalone Workstation license does not include Internet access to the Licensed Materials. c. INSTITUTIONAL SUBSCRIPTION: ...

  1. Boerhaave's syndrome: Experience with patients presenting later than 24 hours.

    PubMed

    Ganguly, Amit; Porwal, Manish; Khandeparkar, Jagdish

    2015-01-01

    Boerhaave's syndrome is the most sinister cause of esophageal perforation. Clinical presentation is vague. Diagnostic delays are frequent. As condition is rare therefore no consensus exists on management. A wide variety of management options are described in literature, each with its advantages and disadvantages. We present our experience of managing these cases which presented after 24 hr. Of onset of symptoms with emphasis on primary reinforced repair as first line surgical option. PMID:27522739

  2. Elimination of 24-hour continuous medical resident duty in Quebec

    PubMed Central

    Hamadani, Fadi; Deckelbaum, Dan; Shaheen, Mohammed; Sauvé, Alexandre; Dumitra, Sinziana; Ahmed, Najma; Latulippe, Jean-François; Balaa, Fady; Walsh, Mark; Fata, Paola

    2016-01-01

    Summary In 2012 Quebec limited continuous in-hospital duty to 16 consecutive hours for all residents regardless of postgraduate (PGY) level. The new restrictions in Quebec appeared to have a profound, negative effect on the quality of life of surgical residents at McGill University and a perceived detrimental effect on the delivery of surgical education and patient care. Here we discuss the results of a nationwide survey that we created and distributed to general surgery residents across Canada to capture and compare their perceptions of the changes to duty hour restrictions. PMID:26574704

  3. Sun Blasts 6 CMEs in 24 Hour Period

    NASA Video Gallery

    This movie from the chronograph on board the SOlar and Heliospheric Observatory (SOHO), shows the sun's atmosphere – the corona – from September 17 to September 20. The sun let loose with at ...

  4. Rethinking the Youth Weight Debate: The 24 Hour Day

    ERIC Educational Resources Information Center

    Dodd, Graham; Biggs, Sarah; Agley, Daniel; Dollman, James; Lushington, Kurt

    2008-01-01

    Approaches to weight management have traditionally focussed on caloric intake versus caloric expenditure. Despite a range of interventions based on these approaches, the proportion of overweight children and adolescents continues to rise. There are increasing indications that other factors, such as sleep duration, may be at play. This commentary…

  5. Attenuated sympathetic nerve responses after 24 hours of bed rest

    NASA Technical Reports Server (NTRS)

    Khan, Mazhar H.; Kunselman, Allen R.; Leuenberger, Urs A.; Davidson, William R Jr; Ray, Chester A.; Gray, Kristen S.; Hogeman, Cynthia S.; Sinoway, Lawrence I.

    2002-01-01

    Bed rest reduces orthostatic tolerance. Despite decades of study, the cause of this phenomenon remains unclear. In this report we examined hemodynamic and sympathetic nerve responses to graded lower body negative pressure (LBNP) before and after 24 h of bed rest. LBNP allows for baroreceptor disengagement in a graded fashion. We measured heart rate (HR), cardiac output (HR x stroke volume obtained by echo Doppler), and muscle sympathetic nerve activity (MSNA) during a progressive and graded LBNP paradigm. Negative pressure was increased by 10 mmHg every 3 min until presyncope or completion of -60 mmHg. After bed rest, LBNP tolerance was reduced in 11 of 13 subjects (P <.023), HR was greater (P <.002), cardiac output was unchanged, and the ability to augment MSNA at high levels of LBNP was reduced (rate of rise for 30- to 60-mmHg LBNP before bed rest 0.073 bursts x min(-1) x mmHg(-1); after bed rest 0.035 bursts x min(-1) x mmHg(-1); P < 0.016). These findings suggest that 24 h of bed rest reduces sympathetic nerve responses to LBNP.

  6. Remotely-sensed, nocturnal, dew point correlates with malaria transmission in Southern Province, Zambia: a time-series study

    PubMed Central

    2014-01-01

    Background Plasmodium falciparum transmission has decreased significantly in Zambia in the last decade. The malaria transmission is influenced by environmental variables. Incorporation of environmental variables in models of malaria transmission likely improves model fit and predicts probable trends in malaria disease. This work is based on the hypothesis that remotely-sensed environmental factors, including nocturnal dew point, are associated with malaria transmission and sustain foci of transmission during the low transmission season in the Southern Province of Zambia. Methods Thirty-eight rural health centres in Southern Province, Zambia were divided into three zones based on transmission patterns. Correlations between weekly malaria cases and remotely-sensed nocturnal dew point, nocturnal land surface temperature as well as vegetation indices and rainfall were evaluated in time-series analyses from 2012 week 19 to 2013 week 36. Zonal as well as clinic-based, multivariate, autoregressive, integrated, moving average (ARIMAX) models implementing environmental variables were developed to model transmission in 2011 week 19 to 2012 week 18 and forecast transmission in 2013 week 37 to week 41. Results During the dry, low transmission season significantly higher vegetation indices, nocturnal land surface temperature and nocturnal dew point were associated with the areas of higher transmission. Environmental variables improved ARIMAX models. Dew point and normalized differentiated vegetation index were significant predictors and improved all zonal transmission models. In the high-transmission zone, this was also seen for land surface temperature. Clinic models were improved by adding dew point and land surface temperature as well as normalized differentiated vegetation index. The mean average error of prediction for ARIMAX models ranged from 0.7 to 33.5%. Forecasts of malaria incidence were valid for three out of five rural health centres; however, with poor

  7. A porcine model of relief of unilateral ureteral obstruction: study on self-repairing capability over multiple time points.

    PubMed

    Liu, Yingying; Sun, Jing; Miao, Lining; Ji, Lei; Luo, Manyu; Li, Bing; Cui, Wenpeng; Wang, Yangwei; Xie, Yuansheng; Chen, Xiangmei

    2016-08-01

    It is still controversial whether renal tubular interstitial fibrosis (TIF) is a reversible process. Although previous studies examining TIF have been carried out in rodents, their kidney size and physiological character differ with humans, and the difference among diverse individuals before and after damage was obvious. Thus an experimental animal model to simulate human kidney disease was urged to be established. In order to clarify whether TIF is reversible, and the exact time points that the kidney has the capacity to be repaired, a porcine relief of unilateral ureteral obstruction (R-UUO) model was developed. Kidney damage and reparation were observed dynamically in vivo over various time points. Pigs were randomized divided into three groups (n = 6): UUO 5 days group, UUO 7 days, and UUO 10 days group. Each porcine in that groups underwent UUO and subsequent R-UUO for three time points. Renal function, histological structure, and protein expressions of α-smooth muscle actin (α-SMA), vimentin and E-cadherin were evaluated at different time points. Following R-UUO after 5 and 7 days of UUO, compared to UUO, serum creatinine levels were significantly decreased. Renal pathological tissue damage was repaired. The expressions of α-SMA and vimentin were decreased and E-cadherin expression was increased (P < 0.05). However, during R-UUO 14, 28, and 56 days after 10 days of UUO, serum creatinine was not decreased significantly. The expressions of α-SMA and vimentin consistently remained at high levels. Renal damage was unable to be restored and resulted in chronic lesions. Kidney damage induced by UUO can be reversed in early stages. However, longer time of UUO with significant levels of TIF showed limited reversibility. The porcine R-UUO model provides an ideal animal model for the investigation of kidney injury and repair as well as for the evaluation of the effect of drug treatment. PMID:27381184

  8. The impact of fertilization on the chicken egg yolk plasma and granule proteome 24 hours post-lay at room temperature: capitalizing on high-pH/low-pH reverse phase chromatography in conjunction with tandem mass tag (TMT) technology.

    PubMed

    Padliya, Neerav D; Qian, Meiqian; Mimi Roy, Sushmita; Chu, Patrick; Zheng, Haiyan; Tess, Alex; Dariani, Maghsoud; Hariri, Robert J

    2015-07-01

    Chicken egg yolk is a rich source of nutrients providing high quality proteins, vitamins, minerals, carotenoids and antioxidants. Chicken egg yolk, recovered from whole egg within 24 hours post-lay has been utilized as a starting material in the preparation of a dietary supplement that has been demonstrated to lead to gains in muscle mass in a human clinical study. Further, an oil derived from chicken egg yolk has been utilized as a topical agent to treat third degree burn injury. The molecular changes that take place in fertilized, chicken egg yolk during the first 24 hours post-lay are not well understood. By studying how the protein composition of egg yolk varies with fertility status, one can utilize this knowledge to develop egg yolk-based products that have been optimized for specific applications. In this study, a direct quantitative comparison was made between the proteome of fertilized chicken egg yolk and the proteome of unfertilized chicken egg yolk, both maintained at 20 °C and analyzed within 24 hours post-lay. Egg yolk proteins from each fertility state were digested with trypsin, labeled with distinct chemical labels (tandem mass tag reagents) and then combined in a 1 : 1 ratio. A TMT-labeled tryptic digest derived from chicken egg yolk proteins (fertilized and unfertilized) was separated using high-pH/low-pH reverse-phase chromatography and analyzed using mass spectrometry. 225 protein identifications were made from this TMT-labeled tryptic digest based on a minimum of 2 unique peptides observed per protein. 9 proteins increased in abundance in fertilized egg yolk relative to unfertilized egg yolk and 9 proteins decreased in abundance in fertilized egg yolk relative to unfertilized egg yolk. Some proteins that increased in abundance in fertilized egg yolk play an important role in angiogenesis (pleiotrophin, histidine rich glycoprotein) and defense against pathogens (mannose-binding lectin, β-defensin 11, serum amyloid P-component, ovostatin

  9. Time-Point Dependent Activation of Autophagy and the UPS in SOD1G93A Mice Skeletal Muscle

    PubMed Central

    Oliván, Sara; Calvo, Ana Cristina; Gasco, Samanta; Muñoz, María Jesús; Zaragoza, Pilar; Osta, Rosario

    2015-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by a selective loss of motor neurons together with a progressive muscle weakness. Albeit the pathophysiological mechanisms of the disease remain unknown, growing evidence suggests that skeletal muscle can be a target of ALS toxicity. In particular, the two main intracellular degradation mechanisms, autophagy and the ubiquitin-proteasome degradative system (UPS) have been poorly studied in this tissue. In this study we investigated the activation of autophagy and the UPS as well as apoptosis in the skeletal muscle from SOD1G93A mice along disease progression. Our results showed a significant upregulation of proteasome activity at early symptomatic stage, while the autophagy activation was found at presymptomatic and terminal stages. The mRNA upregulated levels of LC3, p62, Beclin1, Atg5 and E2f1 were only observed at symptomatic and terminal stages, which reinforced the time-point activation of autophagy. Furthermore, no apoptosis activation was observed along disease progression. The combined data provided clear evidence for the first time that there is a time-point dependent activation of autophagy and UPS in the skeletal muscle from SOD1G93A mice. PMID:26244336

  10. Does Delayed-Time-Point Imaging Improve 18F-FDG-PET in Patients With MALT Lymphoma?

    PubMed Central

    Mayerhoefer, Marius E.; Giraudo, Chiara; Senn, Daniela; Hartenbach, Markus; Weber, Michael; Rausch, Ivo; Kiesewetter, Barbara; Herold, Christian J.; Hacker, Marcus; Pones, Matthias; Simonitsch-Klupp, Ingrid; Müllauer, Leonhard; Dolak, Werner; Lukas, Julius; Raderer, Markus

    2016-01-01

    Purpose To determine whether in patients with extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue lymphoma (MALT), delayed–time-point 2-18F-fluoro-2-deoxy-d-glucose-positron emission tomography (18F-FDG-PET) performs better than standard–time-point 18F-FDG-PET. Materials and Methods Patients with untreated histologically verified MALT lymphoma, who were undergoing pretherapeutic 18F-FDG-PET/computed tomography (CT) and consecutive 18F-FDG-PET/magnetic resonance imaging (MRI), using a single 18F-FDG injection, in the course of a larger-scale prospective trial, were included. Region-based sensitivity and specificity, and patient-based sensitivity of the respective 18F-FDG-PET scans at time points 1 (45–60 minutes after tracer injection, TP1) and 2 (100–150 minutes after tracer injection, TP2), relative to the reference standard, were calculated. Lesion-to-liver and lesion-to-blood SUVmax (maximum standardized uptake values) ratios were also assessed. Results 18F-FDG-PET at TP1 was true positive in 15 o f 23 involved regions, and 18F-FDG-PET at TP2 was true-positive in 20 of 23 involved regions; no false-positive regions were noted. Accordingly, region-based sensitivities and specificities were 65.2% (confidence interval [CI], 45.73%–84.67%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP1; and 87.0% (CI, 73.26%–100%) and 100% (CI, 100%-100%) for 18F-FDG-PET at TP2, respectively. FDG-PET at TP1 detected lymphoma in at least one nodal or extranodal region in 7 of 13 patients, and 18F-FDG-PET at TP2 in 10 of 13 patients; accordingly, patient-based sensitivity was 53.8% (CI, 26.7%–80.9%) for 18F-FDG-PET at TP1, and 76.9% (CI, 54.0%–99.8%) for 18F-FDG-PET at TP2. Lesion-to-liver and lesion-to-blood maximum standardized uptake value ratios were significantly lower at TP1 (ratios, 1.05 ± 0.40 and 1.52 ± 0.62) than at TP2 (ratios, 1.67 ± 0.74 and 2.56 ± 1.10; P = 0.003 and P = 0.001). Conclusions Delayed–time-point imaging

  11. The effects of arm movement on reaction time in patients with latent and active upper trapezius myofascial trigger point

    PubMed Central

    Yassin, Marzieh; Talebian, Saeed; Ebrahimi Takamjani, Ismail; Maroufi, Nader; Ahmadi, Amir; Sarrafzadeh, Javad; Emrani, Anita

    2015-01-01

    Background: Myofascial pain syndrome is a significant source of mechanical pain. The aim of this study was to investigate the effects of arm movement on reaction time in females with latent and active upper trapezius myofascial trigger point. Methods: In this interventional study, a convenience sample of fifteen women with one active MTP, fifteen women with one latent MTP in the upper trapezius, and fifteen normal healthy women were participated. Participants were asked to stand for 10 seconds in an erect standing position. Muscle reaction times were recorded including anterior deltoid (AD), cervical paraspinal (CP) lumbar paraspinal (LP), both of upper trapezius (UT), sternocleidomastoid (SCM) and medial head of gastrocnemius (GcM). Participants were asked to flex their arms in response to a sound stimulus preceded by a warning sound stimulus. Data were analyzed using one-way ANOVA Test. Results: There was significant differences in motor time and reaction time between active and control groups (p< 0.05) except for GcM. There was no significant difference in motor time between active and passive groups except for UT without MTP and SCM (p< 0.05). Also, there were no significant differences in motor times between latent MTP and control groups. Furthermore, there was no significant difference in premotor times between the three groups. Conclusion: The present study shows that patients with active MTP need more time to react to stimulus, but patients with latent MTP are similar to healthy subjects in the reaction time. Patients with active MTP had less compatibility with environmental stimulations, and they responded to a specific stimulation with variability in Surface Electromyography (SEMG). PMID:26913258

  12. A Time Scheduling Model of Logistics Service Supply Chain Based on the Customer Order Decoupling Point: A Perspective from the Constant Service Operation Time

    PubMed Central

    Yang, Yi; Xu, Haitao; Liu, Xiaoyan; Wang, Yijia; Liang, Zhicheng

    2014-01-01

    In mass customization logistics service, reasonable scheduling of the logistics service supply chain (LSSC), especially time scheduling, is benefit to increase its competitiveness. Therefore, the effect of a customer order decoupling point (CODP) on the time scheduling performance should be considered. To minimize the total order operation cost of the LSSC, minimize the difference between the expected and actual time of completing the service orders, and maximize the satisfaction of functional logistics service providers, this study establishes an LSSC time scheduling model based on the CODP. Matlab 7.8 software is used in the numerical analysis for a specific example. Results show that the order completion time of the LSSC can be delayed or be ahead of schedule but cannot be infinitely advanced or infinitely delayed. Obtaining the optimal comprehensive performance can be effective if the expected order completion time is appropriately delayed. The increase in supply chain comprehensive performance caused by the increase in the relationship coefficient of logistics service integrator (LSI) is limited. The relative concern degree of LSI on cost and service delivery punctuality leads to not only changes in CODP but also to those in the scheduling performance of the LSSC. PMID:24715818

  13. A time scheduling model of logistics service supply chain based on the customer order decoupling point: a perspective from the constant service operation time.

    PubMed

    Liu, Weihua; Yang, Yi; Xu, Haitao; Liu, Xiaoyan; Wang, Yijia; Liang, Zhicheng

    2014-01-01

    In mass customization logistics service, reasonable scheduling of the logistics service supply chain (LSSC), especially time scheduling, is benefit to increase its competitiveness. Therefore, the effect of a customer order decoupling point (CODP) on the time scheduling performance should be considered. To minimize the total order operation cost of the LSSC, minimize the difference between the expected and actual time of completing the service orders, and maximize the satisfaction of functional logistics service providers, this study establishes an LSSC time scheduling model based on the CODP. Matlab 7.8 software is used in the numerical analysis for a specific example. Results show that the order completion time of the LSSC can be delayed or be ahead of schedule but cannot be infinitely advanced or infinitely delayed. Obtaining the optimal comprehensive performance can be effective if the expected order completion time is appropriately delayed. The increase in supply chain comprehensive performance caused by the increase in the relationship coefficient of logistics service integrator (LSI) is limited. The relative concern degree of LSI on cost and service delivery punctuality leads to not only changes in CODP but also to those in the scheduling performance of the LSSC. PMID:24715818

  14. Enhancing the focal-resolution of aeroacoustic time-reversal using a point sponge-layer damping technique.

    PubMed

    Mimani, A; Doolan, C J; Medwell, P R

    2014-09-01

    This letter presents the Point-Time-Reversal-Sponge-Layer (PTRSL) technique to enhance the focal-resolution of aeroacoustic Time-Reversal (TR). A PTRSL is implemented on a square domain centered at the predicted source location and is based on damping the radial components of the incoming and outgoing fluxes propagating toward and away from the source, respectively. A PTRSL is shown to overcome the conventional half-wavelength diffraction-limit; its implementation significantly reduces the focal spot size to one-fifth of a wavelength for a monopole source. Furthermore, PTRSL reduces the focal spots of a dipole source to three-tenths of a wavelength, as compared to three-fifths without its implementation. PMID:25190421

  15. Impacts of real-time satellite clock errors on GPS precise point positioning-based troposphere zenith delay estimation

    NASA Astrophysics Data System (ADS)

    Shi, Junbo; Xu, Chaoqian; Li, Yihe; Gao, Yang

    2015-08-01

    Global Positioning System (GPS) has become a cost-effective tool to determine troposphere zenith total delay (ZTD) with accuracy comparable to other atmospheric sensors such as the radiosonde, the water vapor radiometer, the radio occultation and so on. However, the high accuracy of GPS troposphere ZTD estimates relies on the precise satellite orbit and clock products available with various latencies. Although the International GNSS Service (IGS) can provide predicted orbit and clock products for real-time applications, the predicted clock accuracy of 3 ns cannot always guarantee the high accuracy of troposphere ZTD estimates. Such limitations could be overcome by the use of the newly launched IGS real-time service which provides 5 cm orbit and 0.2-1.0 ns (an equivalent range error of 6-30 cm) clock products in real time. Considering the relatively larger magnitude of the clock error than that of the orbit error, this paper investigates the effect of real-time satellite clock errors on the GPS precise point positioning (PPP)-based troposphere ZTD estimation. Meanwhile, how the real-time satellite clock errors impact the GPS PPP-based troposphere ZTD estimation has also been studied to obtain the most precise ZTD solutions. First, two types of real-time satellite clock products are assessed with respect to the IGS final clock product in terms of accuracy and precision. Second, the real-time GPS PPP-based troposphere ZTD estimation is conducted using data from 34 selected IGS stations over three independent weeks in April, July and October, 2013. Numerical results demonstrate that the precision, rather than the accuracy, of the real-time satellite clock products impacts the real-time PPP-based ZTD solutions more significantly. In other words, the real-time satellite clock product with better precision leads to more precise real-time PPP-based troposphere ZTD solutions. Therefore, it is suggested that users should select and apply real-time satellite products with

  16. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases

    PubMed Central

    Toriihara, Akira; Tsunoda, Atsunobu; Takemoto, Akira; Kubota, Kazunori; Machida, Youichi; Tateishi, Ukihide

    2015-01-01

    Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT), magnetic resonance imaging (MRI), and dual-time-point 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2-weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated 18F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated 18F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI. PMID:27408892

  17. Location and release time identification of pollution point source in river networks based on the Backward Probability Method.

    PubMed

    Ghane, Alireza; Mazaheri, Mehdi; Mohammad Vali Samani, Jamal

    2016-09-15

    The pollution of rivers due to accidental spills is a major threat to environment and human health. To protect river systems from accidental spills, it is essential to introduce a reliable tool for identification process. Backward Probability Method (BPM) is one of the most recommended tools that is able to introduce information related to the prior location and the release time of the pollution. This method was originally developed and employed in groundwater pollution source identification problems. One of the objectives of this study is to apply this method in identifying the pollution source location and release time in surface waters, mainly in rivers. To accomplish this task, a numerical model is developed based on the adjoint analysis. Then the developed model is verified using analytical solution and some real data. The second objective of this study is to extend the method to pollution source identification in river networks. In this regard, a hypothetical test case is considered. In the later simulations, all of the suspected points are identified, using only one backward simulation. The results demonstrated that all suspected points, determined by the BPM could be a possible pollution source. The proposed approach is accurate and computationally efficient and does not need any simplification in river geometry and flow. Due to this simplicity, it is highly recommended for practical purposes. PMID:27219462

  18. ICESat Laser Altimeter Pointing, Ranging and Timing Calibration from Integrated Residual Analysis: A Summary of Early Mission Results

    NASA Technical Reports Server (NTRS)

    Lutchke, Scott B.; Rowlands, David D.; Harding, David J.; Bufton, Jack L.; Carabajal, Claudia C.; Williams, Teresa A.

    2003-01-01

    On January 12, 2003 the Ice, Cloud and land Elevation Satellite (ICESat) was successfUlly placed into orbit. The ICESat mission carries the Geoscience Laser Altimeter System (GLAS), which consists of three near-infrared lasers that operate at 40 short pulses per second. The instrument has collected precise elevation measurements of the ice sheets, sea ice roughness and thickness, ocean and land surface elevations and surface reflectivity. The accurate geolocation of GLAS's surface returns, the spots from which the laser energy reflects on the Earth's surface, is a critical issue in the scientific application of these data Pointing, ranging, timing and orbit errors must be compensated to accurately geolocate the laser altimeter surface returns. Towards this end, the laser range observations can be fully exploited in an integrated residual analysis to accurately calibrate these geolocation/instrument parameters. Early mission ICESat data have been simultaneously processed as direct altimetry from ocean sweeps along with dynamic crossovers resulting in a preliminary calibration of laser pointing, ranging and timing. The calibration methodology and early mission analysis results are summarized in this paper along with future calibration activities

  19. Beach response dynamics of a littoral cell using a 17-year single-point time series of sand thickness

    USGS Publications Warehouse

    Barnard, P.L.; Hubbard, D.M.; Dugan, J.E.

    2012-01-01

    A 17-year time series of near-daily sand thickness measurements at a single intertidal location was compared with 5. years of semi-annual 3-dimensional beach surveys at the same beach, and at two other beaches within the same littoral cell. The daily single point measurements correlated extremely well with the mean beach elevation and shoreline position of ten high-spatial resolution beach surveys. Correlations were statistically significant at all spatial scales, even for beach surveys 10s of kilometers downcoast, and therefore variability at the single point monitoring site was representative of regional coastal behavior, allowing us to examine nearly two decades of continuous coastal evolution. The annual cycle of beach oscillations dominated the signal, typical of this region, with additional, less intense spectral peaks associated with seasonal wave energy fluctuations (~. 45 to 90. days), as well as full lunar (~. 29. days) and semi-lunar (~. 13. days; spring-neap cycle) tidal cycles. Sand thickness variability was statistically linked to wave energy with a 2. month peak lag, as well as the average of the previous 7-8. months of wave energy. Longer term anomalies in sand thickness were also apparent on time scales up to 15. months. Our analyses suggest that spatially-limited morphological data sets can be extremely valuable (with robust validation) for understanding the details of beach response to wave energy over timescales that are not resolved by typical survey intervals, as well as the regional behavior of coastal systems. ?? 2011.

  20. Dual-time-point FDG-PET/CT Imaging of Temporal Bone Chondroblastoma: A Report of Two Cases.

    PubMed

    Toriihara, Akira; Tsunoda, Atsunobu; Takemoto, Akira; Kubota, Kazunori; Machida, Youichi; Tateishi, Ukihide

    2015-01-01

    Temporal bone chondroblastoma is an extremely rare benign bone tumor. We encountered two cases showing similar imaging findings on computed tomography (CT), magnetic resonance imaging (MRI), and dual-time-point (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/CT. In both cases, CT images revealed temporal bone defects and sclerotic changes around the tumor. Most parts of the tumor showed low signal intensity on T2-weighted MRI images and non-uniform enhancement on gadolinium contrast-enhanced T1-weighted images. No increase in signal intensity was noted in diffusion-weighted images. Dual-time-point PET/CT showed markedly elevated (18)F-FDG uptake, which increased from the early to delayed phase. Nevertheless, immunohistochemical analysis of the resected tumor tissue revealed weak expression of glucose transporter-1 and hexokinase II in both tumors. Temporal bone tumors, showing markedly elevated (18)F-FDG uptake, which increases from the early to delayed phase on PET/CT images, may be diagnosed as malignant bone tumors. Therefore, the differential diagnosis should include chondroblastoma in combination with its characteristic findings on CT and MRI. PMID:27408892

  1. The Elasticity of Time: Associations between Physical Activity and Use of Time in Adolescents

    ERIC Educational Resources Information Center

    Olds, Tim; Ferrar, Katia E.; Gomersall, Sjaan R.; Maher, Carol; Walters, J. L.

    2012-01-01

    The way an individual uses one's time can greatly affect his or her health. The purpose of this article was to examine the cross-sectional cross-elasticity relationships for use of time domains in a sample of Australian adolescents. This study analyzed 24-hour recall time use data collected using the Multimedia Activity Recall for Children and…

  2. 47 CFR 73.1710 - Unlimited time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Unlimited time. 73.1710 Section 73.1710 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1710 Unlimited time. Operation is permitted 24 hours...

  3. 47 CFR 73.1710 - Unlimited time.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Unlimited time. 73.1710 Section 73.1710 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1710 Unlimited time. Operation is permitted 24 hours...

  4. 47 CFR 73.1710 - Unlimited time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Unlimited time. 73.1710 Section 73.1710 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1710 Unlimited time. Operation is permitted 24 hours...

  5. 47 CFR 73.1710 - Unlimited time.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Unlimited time. 73.1710 Section 73.1710 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1710 Unlimited time. Operation is permitted 24 hours...

  6. 47 CFR 73.1710 - Unlimited time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Unlimited time. 73.1710 Section 73.1710 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1710 Unlimited time. Operation is permitted 24 hours...

  7. Rapid earthquake magnitude from real-time GPS precise point positioning for earthquake early warning and emergency response

    NASA Astrophysics Data System (ADS)

    Fang, Rongxin; Shi, Chuang; Song, Weiwei; Wang, Guangxing; Liu, Jingnan

    2014-05-01

    For earthquake early warning (EEW) and emergency response, earthquake magnitude is the crucial parameter to be determined rapidly and correctly. However, a reliable and rapid measurement of the magnitude of an earthquake is a challenging problem, especially for large earthquakes (M>8). Here, the magnitude is determined based on the GPS displacement waveform derived from real-time precise point positioning (PPP). The real-time PPP results are evaluated with an accuracy of 1 cm in the horizontal components and 2-3 cm in the vertical components, indicating that the real-time PPP is capable of detecting seismic waves with amplitude of 1cm horizontally and 2-3cm vertically with a confidence level of 95%. In order to estimate the magnitude, the unique information provided by the GPS displacement waveform is the horizontal peak displacement amplitude. We show that the empirical relation of Gutenberg (1945) between peak displacement and magnitude holds up to nearly magnitude 9.0 when displacements are measured with GPS. We tested the proposed method for three large earthquakes. For the 2010 Mw 7.2 El Mayor-Cucapah earthquake, our method provides a magnitude of M7.18±0.18. For the 2011 Mw 9.0 Tohoku-oki earthquake the estimated magnitude is M8.74±0.06, and for the 2010 Mw 8.8 Maule earthquake the value is M8.7±0.1 after excluding some near-field stations. We therefore conclude that depending on the availability of high-rate GPS observations, a robust value of magnitude up to 9.0 for a point source earthquake can be estimated within 10s of seconds or a few minutes after an event using a few GPS stations close to the epicenter. The rapid magnitude could be as a pre-requisite for tsunami early warning, fast source inversion, and emergency response is feasible.

  8. Assessing short- and long-time displacements in the Venice coastland by synthetic aperture radar interferometric point target analysis

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Strozzi, Tazio; Tosi, Luigi; Wegmüller, Urs; Werner, Charles; Carbognin, Laura

    2007-03-01

    The Venice Lagoon in Italy is a unique environment vulnerable to loss in surface elevation relative to the mean sea level. We present detailed synthetic aperture radar (SAR) interferometric analyses on persistent point targets for the historical center of Venice, the tourist area of Sottomarina, and the Zennare farmland close to the southern lagoon edge. The selected areas are characterized by different degrees of development and our analyses show the remarkable capability of SAR Interferometric Point Target Analysis (IPTA) to map land displacement rates in densely urbanized zones and to detect movement information on isolated structures with a mm/year accuracy. A detailed analysis of the time series from 1992 to 2000 provided by IPTA shows that the vertical component of the measured displacements are the superposition of a short timescale, generally seasonal, movement on the order of 1 cm that is likely related to the fluctuation of environmental variables (temperature, piezometric head in the aquifer system underlying the lagoon, sea/lagoon water level) and a long-term ground deformation associated with building construction, the geomorphology of the area, and the human development of natural resources. If Venice is confirmed to be generally stable, significant long-term subsidence on the order of 4 mm/year is detected at the Sottomarina coastland. The highest displacement rates, of up to 8-10 mm/year, are recorded in the farmland bounding the lagoon margin where the movements are found to be highly site-specific.

  9. Parcellation of the Healthy Neonatal Brain into 107 Regions Using Atlas Propagation through Intermediate Time Points in Childhood.

    PubMed

    Blesa, Manuel; Serag, Ahmed; Wilkinson, Alastair G; Anblagan, Devasuda; Telford, Emma J; Pataky, Rozalia; Sparrow, Sarah A; Macnaught, Gillian; Semple, Scott I; Bastin, Mark E; Boardman, James P

    2016-01-01

    Neuroimage analysis pipelines rely on parcellated atlases generated from healthy individuals to provide anatomic context to structural and diffusion MRI data. Atlases constructed using adult data introduce bias into studies of early brain development. We aimed to create a neonatal brain atlas of healthy subjects that can be applied to multi-modal MRI data. Structural and diffusion 3T MRI scans were acquired soon after birth from 33 typically developing neonates born at term (mean postmenstrual age at birth 39(+5) weeks, range 37(+2)-41(+6)). An adult brain atlas (SRI24/TZO) was propagated to the neonatal data using temporal registration via childhood templates with dense temporal samples (NIH Pediatric Database), with the final atlas (Edinburgh Neonatal Atlas, ENA33) constructed using the Symmetric Group Normalization (SyGN) method. After this step, the computed final transformations were applied to T2-weighted data, and fractional anisotropy, mean diffusivity, and tissue segmentations to provide a multi-modal atlas with 107 anatomical regions; a symmetric version was also created to facilitate studies of laterality. Volumes of each region of interest were measured to provide reference data from normal subjects. Because this atlas is generated from step-wise propagation of adult labels through intermediate time points in childhood, it may serve as a useful starting point for modeling brain growth during development. PMID:27242423

  10. Parcellation of the Healthy Neonatal Brain into 107 Regions Using Atlas Propagation through Intermediate Time Points in Childhood

    PubMed Central

    Blesa, Manuel; Serag, Ahmed; Wilkinson, Alastair G.; Anblagan, Devasuda; Telford, Emma J.; Pataky, Rozalia; Sparrow, Sarah A.; Macnaught, Gillian; Semple, Scott I.; Bastin, Mark E.; Boardman, James P.

    2016-01-01

    Neuroimage analysis pipelines rely on parcellated atlases generated from healthy individuals to provide anatomic context to structural and diffusion MRI data. Atlases constructed using adult data introduce bias into studies of early brain development. We aimed to create a neonatal brain atlas of healthy subjects that can be applied to multi-modal MRI data. Structural and diffusion 3T MRI scans were acquired soon after birth from 33 typically developing neonates born at term (mean postmenstrual age at birth 39+5 weeks, range 37+2–41+6). An adult brain atlas (SRI24/TZO) was propagated to the neonatal data using temporal registration via childhood templates with dense temporal samples (NIH Pediatric Database), with the final atlas (Edinburgh Neonatal Atlas, ENA33) constructed using the Symmetric Group Normalization (SyGN) method. After this step, the computed final transformations were applied to T2-weighted data, and fractional anisotropy, mean diffusivity, and tissue segmentations to provide a multi-modal atlas with 107 anatomical regions; a symmetric version was also created to facilitate studies of laterality. Volumes of each region of interest were measured to provide reference data from normal subjects. Because this atlas is generated from step-wise propagation of adult labels through intermediate time points in childhood, it may serve as a useful starting point for modeling brain growth during development. PMID:27242423

  11. Locating single-point sources from arrival times containing large picking errors (LPEs): the virtual field optimization method (VFOM)

    NASA Astrophysics Data System (ADS)

    Li, Xi-Bing; Wang, Ze-Wei; Dong, Long-Jun

    2016-01-01

    Microseismic monitoring systems using local location techniques tend to be timely, automatic and stable. One basic requirement of these systems is the automatic picking of arrival times. However, arrival times generated by automated techniques always contain large picking errors (LPEs), which may make the location solution unreliable and cause the integrated system to be unstable. To overcome the LPE issue, we propose the virtual field optimization method (VFOM) for locating single-point sources. In contrast to existing approaches, the VFOM optimizes a continuous and virtually established objective function to search the space for the common intersection of the hyperboloids, which is determined by sensor pairs other than the least residual between the model-calculated and measured arrivals. The results of numerical examples and in-site blasts show that the VFOM can obtain more precise and stable solutions than traditional methods when the input data contain LPEs. Furthermore, we discuss the impact of LPEs on objective functions to determine the LPE-tolerant mechanism, velocity sensitivity and stopping criteria of the VFOM. The proposed method is also capable of locating acoustic sources using passive techniques such as passive sonar detection and acoustic emission.

  12. Locating single-point sources from arrival times containing large picking errors (LPEs): the virtual field optimization method (VFOM).

    PubMed

    Li, Xi-Bing; Wang, Ze-Wei; Dong, Long-Jun

    2016-01-01

    Microseismic monitoring systems using local location techniques tend to be timely, automatic and stable. One basic requirement of these systems is the automatic picking of arrival times. However, arrival times generated by automated techniques always contain large picking errors (LPEs), which may make the location solution unreliable and cause the integrated system to be unstable. To overcome the LPE issue, we propose the virtual field optimization method (VFOM) for locating single-point sources. In contrast to existing approaches, the VFOM optimizes a continuous and virtually established objective function to search the space for the common intersection of the hyperboloids, which is determined by sensor pairs other than the least residual between the model-calculated and measured arrivals. The results of numerical examples and in-site blasts show that the VFOM can obtain more precise and stable solutions than traditional methods when the input data contain LPEs. Furthermore, we discuss the impact of LPEs on objective functions to determine the LPE-tolerant mechanism, velocity sensitivity and stopping criteria of the VFOM. The proposed method is also capable of locating acoustic sources using passive techniques such as passive sonar detection and acoustic emission. PMID:26754955

  13. Reducing start-up time and minimizing energy losses of Microbial Fuel Cells using Maximum Power Point Tracking strategy

    NASA Astrophysics Data System (ADS)

    Molognoni, Daniele; Puig, Sebastià; Balaguer, M. Dolors; Liberale, Alessandro; Capodaglio, Andrea G.; Callegari, Arianna; Colprim, Jesús

    2014-12-01

    Microbial Fuel Cells (MFCs) are considered to be an environmental friendly energy conversion technology. The main limitations that delay their industrialization include low current and power densities achievable and long start-up times. Maximum Power Point Tracking (MPPT) has been proposed as a method to enhance MFCs electrical performances. However, the specialized literature is still lacking of experimental works on scaled-up reactors and/or real wastewater utilization. This study evaluates the impact of a MPPT system applied to MFCs treating swine wastewater in terms of start-up time and long-term performance. For this purpose, two replicate cells were compared, one with applied MPPT control and one working with fixed resistance. Both MFCs were continuously fed with swine wastewater to validate the control system under real and dynamic conditions. The study demonstrated that the automatic resistance control was able to reduce the start-up time of about one month. Moreover, MPPT system increased of 40% the Coulombic efficiency at steady-state conditions, reduced energy losses associated with anode and cathode reactions and limited methanogenic activity in the anode chamber. A power density of 5.0 ± 0.2 W m-3 NAC was achieved feeding the system at an organic loading rate of 10 kg COD m-3 d-1.

  14. A space-time point process model for analyzing and predicting case patterns of diarrheal disease in northwestern Ecuador

    PubMed Central

    Ahn, Jaeil; Johnson, Timothy D.; Bhavnani, Darlene; Eisenberg, Joseph N.S.; Mukherjee, Bhramar

    2014-01-01

    We consider modeling case-patterns under a complex spatial and longitudinal sampling design as conducted via a serial case–control study of diarrheal disease in northwestern Ecuador. We build a two-stage space-time model to understand the role of spatially and temporally referenced covariates that reflect social and natural environments in the sampled region, after accounting for unmeasured residual heterogeneities. All diarrheal case events are collected from 21 sampled communities in Esmeraldes province in Ecuador, during seven sampling cycles from 2003 to 2008. The region of interest comprises 158 communities along a river basin. Prediction of case counts at unsampled communities at a future time is of interest along with estimation of risk-related parameters. We propose a computationally feasible two-stage Bayesian approach to estimate the risk-related parameters and conduct predictive inference. We first apply the log Gaussian Cox process (LGCP), commonly used to model spatial clustering of point patterns, to accommodate temporal variation within the sampled communities. Prediction of the number of cases at unsampled communities at a future time is obtained by a disease mapping model conditional on the expected case counts from Stage I. PMID:24889991

  15. Locating single-point sources from arrival times containing large picking errors (LPEs): the virtual field optimization method (VFOM)

    PubMed Central

    Li, Xi-Bing; Wang, Ze-Wei; Dong, Long-Jun

    2016-01-01

    Microseismic monitoring systems using local location techniques tend to be timely, automatic and stable. One basic requirement of these systems is the automatic picking of arrival times. However, arrival times generated by automated techniques always contain large picking errors (LPEs), which may make the location solution unreliable and cause the integrated system to be unstable. To overcome the LPE issue, we propose the virtual field optimization method (VFOM) for locating single-point sources. In contrast to existing approaches, the VFOM optimizes a continuous and virtually established objective function to search the space for the common intersection of the hyperboloids, which is determined by sensor pairs other than the least residual between the model-calculated and measured arrivals. The results of numerical examples and in-site blasts show that the VFOM can obtain more precise and stable solutions than traditional methods when the input data contain LPEs. Furthermore, we discuss the impact of LPEs on objective functions to determine the LPE-tolerant mechanism, velocity sensitivity and stopping criteria of the VFOM. The proposed method is also capable of locating acoustic sources using passive techniques such as passive sonar detection and acoustic emission. PMID:26754955

  16. Defect states and exceptional point splitting in the band gaps of one-dimensional parity-time lattices.

    PubMed

    Zhu, Xue-Feng

    2015-08-24

    We investigated defect states in band gaps of one-dimensional photonic lattices with delicate modulations of gain and loss that respect parity-time-symmetry (PT-symmetry), viz. n(z) = n*(-z). For the sake of generality, we employ not only periodic structures but also quasiperiodic structures, e.g. Fibonacci sequences, to construct aperiodic PT lattices. Differed from lossless systems for which the defect state is related to only one exceptional point (EP) of the S-matrix, we observed the splitting of one EP into a pair after the introduction of judiciously designed gain and loss in those PT systems, where the defect state enters a non-threshold broken symmetry phase bounded by the EP pair. Some interesting properties associated with defect states and EP splitting are demonstrated, such as enhanced spectral localization, double optical phase abrupt change, and wavelength sensitive reversion of unidirectional transparency. PMID:26368199

  17. Atmospheric plume progression as a function of time and distance from the release point for radioactive isotopes.

    PubMed

    Eslinger, Paul W; Bowyer, Ted W; Cameron, Ian M; Hayes, James C; Miley, Harry S

    2015-10-01

    The radionuclide network of the International Monitoring System comprises up to 80 stations around the world that have aerosol and xenon monitoring systems designed to detect releases of radioactive materials to the atmosphere from nuclear explosions. A rule of thumb description of plume concentration and duration versus time and distance from the release point is useful when designing and deploying new sample collection systems. This paper uses plume development from atmospheric transport modeling to provide a power-law rule describing atmospheric dilution factors as a function of distance from the release point. Consider the plume center-line concentration seen by a ground-level sampler as a function of time based on a short-duration ground-level release of a nondepositing radioactive tracer. The concentration C (Bq m(-3)) near the ground varies with distance from the source with the relationship C=R×A(D,C) ×e (-λ(-1.552+0.0405×D)) × 5.37×10(-8) × D(-2.35) where R is the release magnitude (Bq), D is the separation distance (km) from the ground level release to the measurement location, λ is the decay constant (h(-1)) for the radionuclide of interest and AD,C is an attenuation factor that depends on the length of the sample collection period. This relationship is based on the median concentration for 10 release locations with different geographic characteristics and 365 days of releases at each location, and it has an R(2) of 0.99 for 32 distances from 100 to 3000 km. In addition, 90 percent of the modeled plumes fall within approximately one order of magnitude of this curve for all distances. PMID:26151301

  18. Reference intervals for coagulation times using two point-of-care analysers in healthy pet rabbits (Oryctolagus cuniculus).

    PubMed

    Mentré, V; Bulliot, C; Linsart, A; Ronot, P

    2014-06-28

    The purpose of this study was to establish reference intervals for prothrombin time (PT) and activated partial prothrombin time (aPTT) in healthy rabbits using two different point-of-care analysers (Idexx Coag DX and MS Quick Vet Coag Combo). These intervals would be useful in the diagnosis of coagulopathies and in the determination of coagulation status in critical patients. We are unaware of reports of coagulation values in pet rabbits. Blood samples were analysed from 81 clinically healthy pet rabbits under three years of age (49 females and 32 males). The reference intervals were as follows (non-parametric method for the MS Quick Vet Coag Combo and Box-Cox Robust method for the Idexx Coag DX, p<0.05 limit for statistical significance): PT (MS Quick Vet Coag Combo)=N=33, 17.2-28.5; PT (Idexx Coag DX)=N=48, 10.0-14.8, aPTT (MS Quick Vet Coag Combo)=N=33, 103.2-159.2 and aPTT (Idexx Coag DX)=N=48, 104.2-159.1. PT was significantly longer using the MS Quick Vet Coag Combo. aPTT was significantly shorter with the MS Quick Vet Coag Combo. On each type of analyser, there was no significant difference between sexes and blood sampling sites. A significant difference was present for the use or not of anaesthesia with the MS Quick Vet Coag Combo analyser. This study on healthy pet rabbits will be useful in point-of-care diagnosis of coagulopathies. PMID:24722233

  19. Potential performance of dual-time-point 18F-FDG PET/CT compared with single-time-point imaging for differential diagnosis of metastatic lymph nodes: a meta-analysis.

    PubMed

    Shen, Guohua; Deng, Houfu; Hu, Shuang; Jia, Zhiyun

    2014-10-01

    In recent years, dual-time-point (DTP) fluorine-18 fluorodeoxyglucose PET/computed tomography (CT) has emerged as a new method for evaluating metastatic lymph nodes in cancer patients. We performed this meta-analysis to evaluate the performance of DTP PET/CT compared with single-time-point (STP) imaging for differential diagnosis of lymph nodes metastases. On the basis of data from included studies, pooled sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, and negative likelihood ratio were calculated. Summary receiver-operating characteristic curves were also constructed to assess the diagnostic value of DTP PET/CT and STP imaging in detecting metastatic lymph nodes. Totally, 17 articles were included in the analysis. On a per-patient basis, the pooled sensitivity and specificity were 0.74 [95% confidence interval (CI): 0.68-0.79] and 0.77 (95% CI: 0.72-0.81) for DTP PET/CT and 0.68 (95% CI: 0.61-0.73) and 0.81 (95% CI: 0.78-0.85) for STP PET/CT, respectively. On a per-lesion basis, the pooled sensitivity of DTP and STP PET/CT was 0.82 (95% CI: 0.79-0.84) and 0.80 (95% CI: 0.78-0.83), respectively. The pooled specificity was 0.88 (95% CI: 0.86-0.89) for DTP PET/CT and 0.82 (95% CI: 0.80-0.84) for STP PET/CT. Compared with STP imaging, DTP PET/CT has higher sensitivity but lower specificity in detecting lymph nodes metastases on a per-patient analysis, and DTP PET/CT performs only a little better than STP PET/CT on a per-lesion basis. The current results of our meta-analysis do not support the routine use of DTP imaging for the diagnosis of metastatic lymph nodes. Further prospective research with large samples is required to better define the potential benefits of DTP PET/CT imaging. PMID:25023998

  20. Principal Component Analysis of the Time- and Position-dependent Point-Spread Function of the Advanced Camera for Surveys

    NASA Astrophysics Data System (ADS)

    Jee, M. J.; Blakeslee, J. P.; Sirianni, M.; Martel, A. R.; White, R. L.; Ford, H. C.

    2007-12-01

    We describe the time- and position-dependent point-spread function (PSF) variation of the wide-field channel (WFC) of the Advanced Camera for Surveys (ACS) with the principal component analysis (PCA) technique. The time-dependent change is caused by the temporal variation of the HST focus, whereas the position-dependent PSF variation in ACS WFC at a given focus is mainly the result of changes in aberrations and charge diffusion across the detector, which appear as position-dependent changes in the elongation of the astigmatic core and blurring of the PSF, respectively. Using ˜ 20 ) of principal components or "eigen-PSFs" per exposure can robustly reproduce the observed variation of the ellipticity and size of the PSF. Our primary interest in this investigation is the application of this PSF library to precision weak-lensing analyses, where accurate knowledge of the instrument's PSF is crucial. However, the high fidelity of the model judged from the nice agreement with observed PSFs suggests that the model is potentially also useful in other applications, such as crowded field stellar photometry, galaxy profile fitting, AGN studies, etc., which similarly demand a fair knowledge of the PSFs at objects' locations. Our PSF models, applicable to any WFC image rectified with the Lanczos3 kernel, are publicly available.

  1. A multiscale maximum entropy moment closure for locally regulated space-time point process models of population dynamics.

    PubMed

    Raghib, Michael; Hill, Nicholas A; Dieckmann, Ulf

    2011-05-01

    The prevalence of structure in biological populations challenges fundamental assumptions at the heart of continuum models of population dynamics based only on mean densities (local or global). Individual-based models (IBMs) were introduced during the last decade in an attempt to overcome this limitation by following explicitly each individual in the population. Although the IBM approach has been quite useful, the capability to follow each individual usually comes at the expense of analytical tract ability, which limits the generality of the statements that can be made. For the specific case of spatial structure in populations of sessile (and identical) organisms, space-time point processes with local regulation seem to cover the middle ground between analytical tract ability and a higher degree of biological realism. This approach has shown that simplified representations of fecundity, local dispersal and density-dependent mortality weighted by the local competitive environment are sufficient to generate spatial patterns that mimic field observations. Continuum approximations of these stochastic processes try to distill their fundamental properties, and they keep track of not only mean densities, but also higher order spatial correlations. However, due to the non-linearities involved they result in infinite hierarchies of moment equations. This leads to the problem of finding a 'moment closure'; that is, an appropriate order of (lower order) truncation, together with a method of expressing the highest order density not explicitly modelled in the truncated hierarchy in terms of the lower order densities. We use the principle of constrained maximum entropy to derive a closure relationship for truncation at second order using normalisation and the product densities of first and second orders as constraints, and apply it to one such hierarchy. The resulting 'maxent' closure is similar to the Kirkwood superposition approximation, or 'power-3' closure, but it is

  2. Dynamics of the Sanières rockslide from the time-lapse analysis of airborne and terrestrial point clouds.

    NASA Astrophysics Data System (ADS)

    Malet, Jean-Philippe; Skupinsky, Gregorz; Guérin, Antoine; Derron, Marc-Henri; Bornemann, Pierrick

    2015-04-01

    The Roche-Plombée rocsklide (South French Alps) has been triggered in early August 2013 in the lower part of the Sanières catchment as a result of undercutting of the torrent banks after a debris flow event. During several days, a large amount of debris have been mobilised along a 300m length cliff. Deposits have reached and filled the torrential channel downslope. Several field observations carried out in the following weeks have shown the progressive opening of fissures along the main scarp. Today, large volumes of unstable debris are still available on the slope. Local stakeholders are now expecting the formation of a debris-dam in the channel which could lead to a debris flow in case of failure. This work is focused on the use of remote sensing techniques (terrestrial photogrammetry, airborne and terrestrical LiDAR) to detect and quantify spatial and temporal distribution of materials on the slope. The Structure From Motion (SFM) technique is used to generate multi-date high-resolution digital elevation models (HRDEMs) in order to quantify volumes changes; a time-lapse image correlation analysis of four terrestrial LiDAR scans is used to estimate displacements at the surface. The analysis of the point cloud dataset indicates a global deformation of the rockslope along several slip surfaces. The progressive development of the main scarp with velocity of a few cm.month-1 is also monitored. The analysis of an airborne LiDAR point cloud allows to characterize the main discontinuities. The possibility of extension of the rockslide is discussed.

  3. Time-frequency analysis of single-point engine-block vibration measurements for multiple excitation-event identification

    NASA Astrophysics Data System (ADS)

    Vulli, S.; Dunne, J. F.; Potenza, R.; Richardson, D.; King, P.

    2009-04-01

    The short-term-Fourier-transform (STFT) is used to identify different sources of IC engine-block vibration from single-point acceleration measurements taken with a commercial knock sensor. Interest is focused on using the STFT to distinguish normal combustion from other sources of excitation including valve impact, injector pulses, and abnormal combustion, such as knocking. Positive identification of these other events using a single method can be useful for pre-processing of measured knock-sensor data for neural-network-based reconstruction of cylinder pressure. It can also be useful separately as part of a fast knock detection system. A series of experiments is discussed to create the data to isolate these different events on a 3-cylinder gasoline engine. In each case, the measured data is processed using the STFT to attempt to isolate the occurrence of particular events in the time domain. Four classes of experiments are undertaken: (i) an un-fired (motored) engine, driven by a dynamometer, with spark plugs fitted, and then removed, to isolate valve impact; (ii) a fired engine running under idle conditions, to contrast no-load combustion with no combustion; (iii) a part-loaded engine running normally, and then running with one injector switched-off, and (iv) a fully-loaded engine running normally, and then running with knock-control switched-off. The paper shows that a single Time-frequency analysis method, applied to knock sensor data in the form of an appropriately-tuned STFT, can effectively identify the occurrence of these events in the time domain if responses are adequately separated and strong enough.

  4. Adaptive error detection for HDR/PDR brachytherapy: Guidance for decision making during real-time in vivo point dosimetry

    SciTech Connect

    Kertzscher, Gustavo Andersen, Claus E.; Tanderup, Kari

    2014-05-15

    Purpose: This study presents an adaptive error detection algorithm (AEDA) for real-timein vivo point dosimetry during high dose rate (HDR) or pulsed dose rate (PDR) brachytherapy (BT) where the error identification, in contrast to existing approaches, does not depend on an a priori reconstruction of the dosimeter position. Instead, the treatment is judged based on dose rate comparisons between measurements and calculations of the most viable dosimeter position provided by the AEDA in a data driven approach. As a result, the AEDA compensates for false error cases related to systematic effects of the dosimeter position reconstruction. Given its nearly exclusive dependence on stable dosimeter positioning, the AEDA allows for a substantially simplified and time efficient real-time in vivo BT dosimetry implementation. Methods: In the event of a measured potential treatment error, the AEDA proposes the most viable dosimeter position out of alternatives to the original reconstruction by means of a data driven matching procedure between dose rate distributions. If measured dose rates do not differ significantly from the most viable alternative, the initial error indication may be attributed to a mispositioned or misreconstructed dosimeter (false error). However, if the error declaration persists, no viable dosimeter position can be found to explain the error, hence the discrepancy is more likely to originate from a misplaced or misreconstructed source applicator or from erroneously connected source guide tubes (true error). Results: The AEDA applied on twoin vivo dosimetry implementations for pulsed dose rate BT demonstrated that the AEDA correctly described effects responsible for initial error indications. The AEDA was able to correctly identify the major part of all permutations of simulated guide tube swap errors and simulated shifts of individual needles from the original reconstruction. Unidentified errors corresponded to scenarios where the dosimeter position was

  5. CONSORT: Effects of adding adefovirdipivoxil to peginterferon alfa-2a at different time points on HBeAg-positivepatients

    PubMed Central

    Zhang, Ka; Cao, Hong; Liang, Jiayi; Shu, Xin; Sun, Haixia; Li, Gang; Xu, Qihuan

    2016-01-01

    Abstract Background: The aims of this study were to compare the efficacy and safety of the addition of adefovir dipivoxil (ADV) (started at different time points) to pegylated interferon alpha-2a (PEG-INF-α2a) and PEG-INF-α2a monotherapy. This prospective, randomized study sought to evaluate the safety and efficacy of the combination of PEG-INF-α2a and ADV at different time points.120 patients were randomized into groups that received PEG-INF-α2a as monotherapy (group A) or in combination with ADV started at week 0 (group B), 12 (group C), or 24 (group D). All patients were followed for 48 weeks. Efficacy and safety analyses were performed. Methods: Patients in group a received 135 μg of PEG-INF-α2a by subcutaneous injection once weekly for 48 weeks. Patients in the ADV add-on group received 135 μg of PEG-INF-α2a subcutaneously once weekly and received 10 mg of ADV administered once daily for 48 weeks. HBV DNA, HBsAg, HBeAg, and hepatitis B e antibody levels were determined. Responses were determined at week 12 (ADV add-on), the end of treatment for PEG-INF-α2a (48weeks) and ADV (EOT) and at the end of 96 weeks of follow-up (EOF). Results: The rate of HBV DNA loss were higher in the combination groups than group A at the week 12, week 48, the EOT and EOF (P < 0.05). The rates of HBeAg seroconversion and HBsAg loss were similar among the treatment groups (P>0.05). The alanineaminotransferase (ALT) normalization rate was higher in the combination group than group A only at the EOT (P = 0.007). By the EOF, the patients with ADV added at week 12 achieved higher rates of HBV DNA loss (71.9%), HBeAg seroconversion (50.0%), HBsAg loss (15.6%), and ALT normalization (78.1%). Conclusions: PEG-INF-α2a plus ADV combination therapy is safe and superior to PEG-INF-α2amonotherapyfor decreasing serum HBV DNA and normalizing the ALT level but has no significant impact on the rate of HBeAg seroconversion and HBsAg loss. Adding ADV at week 12 may be an

  6. Time-Tag Generation Script

    NASA Technical Reports Server (NTRS)

    Jackson, Dan E.

    2010-01-01

    Time-Tag Generation Script (TTaGS) is an application program, written in the AWK scripting language, for generating commands for aiming one Ku-band antenna and two S-band antennas for communicating with spacecraft. TTaGS saves between 2 and 4 person-hours per every 24 hours by automating the repetitious process of building between 150 and 180 antenna-control commands. TTaGS reads a text database of communication satellite schedules and a text database of satellite rise and set times and cross-references items in the two databases. It then compares the scheduled start and stop with the geometric rise and set to compute the times to execute antenna control commands. While so doing, TTaGS determines whether to generate commands for guidance, navigation, and control computers to tell them which satellites to track. To help prevent Ku-band irradiation of the Earth, TTaGS accepts input from the user about horizon tolerance and accordingly restricts activation and effects deactivation of the transmitter. TTaGS can be modified easily to enable tracking of additional satellites and for such other tasks as reading Sun-rise/set tables to generate commands to point the solar photovoltaic arrays of the International Space Station at the Sun.

  7. Effect of time-of-flight and point spread function modeling on detectability of myocardial defects in PET

    SciTech Connect

    Schaefferkoetter, Joshua; Ouyang, Jinsong; Rakvongthai, Yothin; El Fakhri, Georges; Nappi, Carmela

    2014-06-15

    Purpose: A study was designed to investigate the impact of time-of-flight (TOF) and point spread function (PSF) modeling on the detectability of myocardial defects. Methods: Clinical FDG-PET data were used to generate populations of defect-present and defect-absent images. Defects were incorporated at three contrast levels, and images were reconstructed by ordered subset expectation maximization (OSEM) iterative methods including ordinary Poisson, alone and with PSF, TOF, and PSF+TOF. Channelized Hotelling observer signal-to-noise ratio (SNR) was the surrogate for human observer performance. Results: For three iterations, 12 subsets, and no postreconstruction smoothing, TOF improved overall defect detection SNR by 8.6% as compared to its non-TOF counterpart for all the defect contrasts. Due to the slow convergence of PSF reconstruction, PSF yielded 4.4% less SNR than non-PSF. For reconstruction parameters (iteration number and postreconstruction smoothing kernel size) optimizing observer SNR, PSF showed larger improvement for faint defects. The combination of TOF and PSF improved mean detection SNR as compared to non-TOF and non-PSF counterparts by 3.0% and 3.2%, respectively. Conclusions: For typical reconstruction protocol used in clinical practice, i.e., less than five iterations, TOF improved defect detectability. In contrast, PSF generally yielded less detectability. For large number of iterations, TOF+PSF yields the best observer performance.

  8. The effects of cuing in time-shared tasks. [for aircraft flight route-way-point information

    NASA Technical Reports Server (NTRS)

    Chechile, R. A.; Sadoski, D. M.

    1983-01-01

    The results of two divided-attention experiments involving the editing of route-way-point displays on an avionics computer unit are reported. Two side tasks were required of the subjects, and either no cue, verbal cues appearing on the CRT, or symbolic cues (lights on the keyboard adjacent to keys to be used) were given to facilitate the primary editing task. Forty female and 30 male undergraduates were trained in the separate and combined tasks and divided randomly into groups of 25 for the cuing tests. A second test with three 10-subject groups was conducted at least one month later to investigate the efficacy of cuing for infrequently used procedures. It is found that only symbolic cuing significantly improved primary-task performance, increasing editing accuracy in the repetitive tests and reducing editing time in the delayed tests. Verbal cuing, probably because it requires additional cognitive effort, has no significant beneficial effect. These results are considered important for designing instruments for work environments requiring the performance of concurrent tasks, and as aircraft cockpits.

  9. Effect of time-of-flight and point spread function modeling on detectability of myocardial defects in PET

    PubMed Central

    Schaefferkoetter, Joshua; Ouyang, Jinsong; Rakvongthai, Yothin; Nappi, Carmela; El Fakhri, Georges

    2014-01-01

    Purpose: A study was designed to investigate the impact of time-of-flight (TOF) and point spread function (PSF) modeling on the detectability of myocardial defects. Methods: Clinical FDG-PET data were used to generate populations of defect-present and defect-absent images. Defects were incorporated at three contrast levels, and images were reconstructed by ordered subset expectation maximization (OSEM) iterative methods including ordinary Poisson, alone and with PSF, TOF, and PSF+TOF. Channelized Hotelling observer signal-to-noise ratio (SNR) was the surrogate for human observer performance. Results: For three iterations, 12 subsets, and no postreconstruction smoothing, TOF improved overall defect detection SNR by 8.6% as compared to its non-TOF counterpart for all the defect contrasts. Due to the slow convergence of PSF reconstruction, PSF yielded 4.4% less SNR than non-PSF. For reconstruction parameters (iteration number and postreconstruction smoothing kernel size) optimizing observer SNR, PSF showed larger improvement for faint defects. The combination of TOF and PSF improved mean detection SNR as compared to non-TOF and non-PSF counterparts by 3.0% and 3.2%, respectively. Conclusions: For typical reconstruction protocol used in clinical practice, i.e., less than five iterations, TOF improved defect detectability. In contrast, PSF generally yielded less detectability. For large number of iterations, TOF+PSF yields the best observer performance. PMID:24877836

  10. Clinical Impact of Time-of-Flight and Point Response Modeling in PET Reconstructions: A Lesion Detection Study

    PubMed Central

    Schaefferkoetter, Joshua; Casey, Michael; Townsend, David; Fakhri, Georges El

    2013-01-01

    Time-of-flight (TOF) and point spread function (PSF) modeling have been shown to improve PET reconstructions, but the impact on physicians in the clinical setting has not been thoroughly investigated. A lesion detection and localization study was performed using simulated lesions in real patient images. Four reconstruction schemes were considered: ordinary Poisson OSEM (OP) alone and combined with TOF, PSF, and TOF+PSF. The images were presented to physicians experienced in reading PET images, and the performance of each was quantified using localization receiver operating characteristic (LROC). Numerical observers (non-prewhitening and Hotelling) were used to identify optimal reconstruction parameters, and observer SNR was compared to the performance of the physicians. The numerical models showed good agreement with human performance, and best performance was achieved by both when using TOF+PSF. These findings suggest a large potential benefit of TOF+PSF for oncology PET studies, especially in the detection of small, low-intensity, focal disease in larger patients. PMID:23403399

  11. The use of multiple versus single assessment time points to improve screening accuracy in identifying children at risk for later serious antisocial behavior.

    PubMed

    Petras, Hanno; Buckley, Jacquelyn A; Leoutsakos, Jeannie-Marie S; Stuart, Elizabeth A; Ialongo, Nicholas S

    2013-10-01

    Guided by Kraemer et al.'s (Psychological Methods, 3:257-271, 1999) framework for measuring the potency of risk factors, we sought to improve on the classification accuracy reported in Petras et al. (Journal of the American Academy of Child and Adolescent Psychiatry 43:88-96, 2004a) and Petras et al. (Journal of the American Academy of Child and Adolescent Psychiatry 44:790-797, 2005) by using multiple as opposed to single point in time assessments of early aggressive and disruptive behavior in the classification of youth who would likely benefit from targeted preventive interventions. Different from Petras et al. (2004a, 2005), the outcome used in this study included serious antisocial behavior in young adulthood as well as in adolescence. Among males, the use of multiple time points did not yield greater classification accuracy than the highest single time points, that is, third and fifth grades. For females, although fifth grade represented the best single time point in terms of classification accuracy, no significant association was found between earlier time points and the later outcome, rendering a test of the multiple time points hypothesis moot. The findings presented in this study have strong implications for the design of targeted intervention for violence prevention, indicating that the screening quality based on aggression ratings during the elementary years is rather modest, particularly for females. PMID:23408279

  12. 14 CFR 135.273 - Duty period limitations and rest time requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... time, using Coordinated Universal Time or local time, that begins at midnight and ends 24 hours later... calculated using either Coordinated Universal Time or local time to reflect the total elapsed time. Flight... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Duty period limitations and rest...

  13. 14 CFR 135.273 - Duty period limitations and rest time requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... time, using Coordinated Universal Time or local time, that begins at midnight and ends 24 hours later... calculated using either Coordinated Universal Time or local time to reflect the total elapsed time. Flight... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Duty period limitations and rest...

  14. 14 CFR 135.273 - Duty period limitations and rest time requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... time, using Coordinated Universal Time or local time, that begins at midnight and ends 24 hours later... calculated using either Coordinated Universal Time or local time to reflect the total elapsed time. Flight... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Duty period limitations and rest...

  15. Effects of ulinastatin administered at different time points on the pathological morphologies of the lung tissues of rats with hyperthermia

    PubMed Central

    QIN, ZAI-SHENG; TIAN, PEI; WU, XIA; YU, HONG-MEI; GUO, NA

    2014-01-01

    Hyperthermia not only directly induces cell injury of body tissues, but also causes the body to release large amounts of inflammatory mediators and cells with extensive biological activities to induce a systemic inflammatory response and immune dysfunction. Thus, hyperthermia causes systemic inflammatory response syndrome, aggravating injuries to various organs. This study aimed to observe the effects of ulinastatin (UTI) administered at different time points on the cellular morphologies of the lung tissues of rats with systemic hyperthermia. A total of 40 male Sprague Dawley rats were randomly divided into five groups: The normal control group (C group), the hyperthermia group without medication (H group), the hyperthermia and UTI pre-treatment group (HU group), the group treated with UTI at 1 h after hyperthermia (HU1 group), and the group treated with UTI at 2 h after hyperthermia (HU2 group). The systemic hyperthermia rat model was established in a heating chamber with a biological oxygen supply. For the HU, HU1 and HU2 groups, UTI (5×104 U/kg) was administered at different time points. For the C and H groups, an equivalent volume of normal saline was administered. During heating, the respiratory frequency and rectal temperature were measured and recorded once every 30 min. After 2.5 h of heating, the wet/dry weight (W/D) ratio of the lung tissues of the rats was measured. Additionally, the cellular morphologies of the lung tissues were observed under light and electron microscopes. The respiratory frequencies and lung tissue W/D ratios of the rats in the various hyperthermia groups were significantly higher than those of the rats in the C group (all P<0.05). The respiratory frequencies and lung tissue W/D values of the HU and HU1 groups were significantly lower than those of the H group (all P<0.05). Under the light microscope, the bronchial surrounding tissues of the HU and HU1 groups were loose, and the majority of the pulmonary alveolar structures were

  16. The Origin of Sterol Biosynthesis: A Time-Point for the Evolution of Eukaryotes and the Presence of O2

    NASA Astrophysics Data System (ADS)

    Pearson, A.; Budin, M.; Brocks, J. J.

    2003-12-01

    The evolution of sterol biosynthesis is of critical interest to geoscientists as well as to evolutionary biologists. The first enzyme in the pathway, squalene monooxygenase (Sqmo), requires molecular oxygen (O2), suggesting that this process post-dates the evolution of Cyanobacteria. Additionally, the presence of steranes in ancient rocks marks the suggested time-point of eukaryogenesis(1). Sterol biosynthesis is viewed primarily as a eukaryotic process, and the frequency of its occurrence in bacteria long has been a subject of controversy. In this work, 19 protein gene sequences for Sqmo from eukaryotes were compared to all available complete and partial prokaryotic genomes. Twelve protein gene sequences representing oxidosqualene cyclase (Osc), the second enzyme of the sterol biosynthetic pathway, also were examined. The only unequivocal matches among the bacteria were the alpha-proteobacterium, Methylococcus capsulatus, in which sterol biosynthesis already is known, and the planctomycete, Gemmata obscuriglobus. The latter species contains the most abbreviated sterol pathway yet identified in any organism. Experiments show that the major sterols in Gemmata are lanosterol and its uncommon isomer, parkeol. In bacteria, the sterol biosynthesis genes occupy a contiguous coding region and may represent a single operon. Phylogenetic trees show that the sterol pathway in bacteria and eukaryotes has a common ancestry. Gemmata may retain the most ancient remnants of the pathway's origin, and it is likely that sterol biosynthesis in eukaryotes was acquired through gene transfer from bacteria. However, this work indicates that no known prokaryotes could produce the 24-ethyl steranes found in Archaean rocks(1). Therefore these compounds remain indicative of the presence of both eukaryotes and O2 at 2.7 Ga. 1. J. J. Brocks, G. A. Logan, R. Buick, R. E. Summons, (1999) Science 285, 1033-1036.

  17. Molecular network, pathway, and functional analysis of time-dependent gene changes associated with pancreatic cancer susceptibility to oncolytic vaccinia virotherapy

    PubMed Central

    Haddad, Dana; Socci, Nicholas; Chen, Chun-Hao; Chen, Nanhai G; Zhang, Qian; Carpenter, Susanne G; Mittra, Arjun; Szalay, Aladar A; Fong, Yuman

    2016-01-01

    Background: Pancreatic cancer is a fatal disease associated with resistance to conventional therapies. This study aimed to determine changes in gene expression patterns associated with infection and susceptibility of pancreatic cancer cells to an oncolyticvaccinia virus, GLV-1h153, carrying the human sodium iodide symporter for deep tissue imaging of virotherapy. Methods: Replication and susceptibility of pancreatic adenocarcinoma PANC-1 cells to GLV-1h153 was confirmed with replication and cytotoxicity assays. PANC-1 cells were then infected with GLV-1h153 and near-synchronous infection confirmed via flow cytometry of viral-induced green fluorescent protein (GFP) expression. Six and 24 hours after infection, three samples of each time point were harvested, and gene expression patterns assessed using HG-U133A cDNA microarray chips as compared to uninfected control. Differentially expressed genes were identified using Bioconductor LIMMA statistical analysis package. A fold change of 2.0 or above was used as a cutoff, with a P value of 0.01. The gene list was then analyzed using Ingenuity Pathways Analysis software. Results: Differential gene analysis revealed a total of 12,412 up- and 11,065 downregulated genes at 6 and 24 hours postinfection with GLV-1h153 as compared to control. At 6 hours postinfection. A total of 139 genes were either up or downregulated >twofold (false discovery rate < 0.05), of which 124 were mapped by Ingenuity Pathway Analysis (IPA). By 24 hours postinfection, a total of 5,698 genes were identified and 5,563 mapped by IPA. Microarray revealed gene expression changes, with gene networks demonstrating downregulation of processes such as cell death, cell cycle, and DNA repair, and upregulation of infection mechanisms (P < 0.01). Six hours after infection, gene changes involved pathways such as HMGB-1, interleukin (IL)-2, IL-6, IL-8, janus kinase/signal tranducer and activator of transcription (JAK/STAT), interferon, and ERK 5 signaling (P < 0

  18. Change Points in the Population Trends of Aerial-Insectivorous Birds in North America: Synchronized in Time across Species and Regions.

    PubMed

    Smith, Adam C; Hudson, Marie-Anne R; Downes, Constance M; Francis, Charles M

    2015-01-01

    North American populations of aerial insectivorous birds are in steep decline. Aerial insectivores (AI) are a group of bird species that feed almost exclusively on insects in flight, and include swallows, swifts, nightjars, and flycatchers. The causes of the declines are not well understood. Indeed, it is not clear when the declines began, or whether the declines are shared across all species in the group (e.g., caused by changes in flying insect populations) or specific to each species (e.g., caused by changes in species' breeding habitat). A recent study suggested that population trends of aerial insectivores changed for the worse in the 1980s. If there was such a change point in trends of the group, understanding its timing and geographic pattern could help identify potential causes of the decline. We used a hierarchical Bayesian, penalized regression spline, change point model to estimate group-level change points in the trends of 22 species of AI, across 153 geographic strata of North America. We found evidence for group-level change points in 85% of the strata. Change points for flycatchers (FC) were distinct from those for swallows, swifts and nightjars (SSN) across North America, except in the Northeast, where all AI shared the same group-level change points. During the 1980s, there was a negative change point across most of North America, in the trends of SSN. For FC, the group-level change points were more geographically variable, and in many regions there were two: a positive change point followed by a negative change point. This group-level synchrony in AI population trends is likely evidence of a response to a common environmental factor(s) with similar effects on many species across broad spatial extents. The timing and geographic patterns of the change points that we identify here should provide a spring-board for research into the causes behind aerial insectivore declines. PMID:26147572

  19. Change Points in the Population Trends of Aerial-Insectivorous Birds in North America: Synchronized in Time across Species and Regions

    PubMed Central

    Smith, Adam C.; Hudson, Marie-Anne R.; Downes, Constance M.; Francis, Charles M.

    2015-01-01

    North American populations of aerial insectivorous birds are in steep decline. Aerial insectivores (AI) are a group of bird species that feed almost exclusively on insects in flight, and include swallows, swifts, nightjars, and flycatchers. The causes of the declines are not well understood. Indeed, it is not clear when the declines began, or whether the declines are shared across all species in the group (e.g., caused by changes in flying insect populations) or specific to each species (e.g., caused by changes in species’ breeding habitat). A recent study suggested that population trends of aerial insectivores changed for the worse in the 1980s. If there was such a change point in trends of the group, understanding its timing and geographic pattern could help identify potential causes of the decline. We used a hierarchical Bayesian, penalized regression spline, change point model to estimate group-level change points in the trends of 22 species of AI, across 153 geographic strata of North America. We found evidence for group-level change points in 85% of the strata. Change points for flycatchers (FC) were distinct from those for swallows, swifts and nightjars (SSN) across North America, except in the Northeast, where all AI shared the same group-level change points. During the 1980s, there was a negative change point across most of North America, in the trends of SSN. For FC, the group-level change points were more geographically variable, and in many regions there were two: a positive change point followed by a negative change point. This group-level synchrony in AI population trends is likely evidence of a response to a common environmental factor(s) with similar effects on many species across broad spatial extents. The timing and geographic patterns of the change points that we identify here should provide a spring-board for research into the causes behind aerial insectivore declines. PMID:26147572

  20. Infectious Disease Management through Point-of-Care Personalized Medicine Molecular Diagnostic Technologies

    PubMed Central

    Bissonnette, Luc; Bergeron, Michel G.

    2012-01-01

    Infectious disease management essentially consists in identifying the microbial cause(s) of an infection, initiating if necessary antimicrobial therapy against microbes, and controlling host reactions to infection. In clinical microbiology, the turnaround time of the diagnostic cycle (>24 hours) often leads to unnecessary suffering and deaths; approaches to relieve this burden include rapid diagnostic procedures and more efficient transmission or interpretation of molecular microbiology results. Although rapid nucleic acid-based diagnostic testing has demonstrated that it can impact on the transmission of hospital-acquired infections, we believe that such life-saving procedures should be performed closer to the patient, in dedicated 24/7 laboratories of healthcare institutions, or ideally at point of care. While personalized medicine generally aims at interrogating the genomic information of a patient, drug metabolism polymorphisms, for example, to guide drug choice and dosage, personalized medicine concepts are applicable in infectious diseases for the (rapid) identification of a disease-causing microbe and determination of its antimicrobial resistance profile, to guide an appropriate antimicrobial treatment for the proper management of the patient. The implementation of point-of-care testing for infectious diseases will require acceptance by medical authorities, new technological and communication platforms, as well as reimbursement practices such that time- and life-saving procedures become available to the largest number of patients. PMID:25562799

  1. Identification of a time-varying point source in a system of two coupled linear diffusion-advection- reaction equations: application to surface water pollution

    NASA Astrophysics Data System (ADS)

    Hamdi, Adel

    2009-11-01

    This paper deals with the identification of a point source (localization of its position and recovering the history of its time-varying intensity function) that constitutes the right-hand side of the first equation in a system of two coupled 1D linear transport equations. Assuming that the source intensity function vanishes before reaching the final control time, we prove the identifiability of the sought point source from recording the state relative to the second coupled transport equation at two observation points framing the source region. Note that at least one of the two observation points should be strategic. We establish an identification method that uses these records to identify the source position as the root of a continuous and strictly monotonic function. Whereas the source intensity function is recovered using a recursive formula without any need of an iterative process. Some numerical experiments on a variant of the surface water pollution BOD-OD coupled model are presented.

  2. A Jiles-Atherton and fixed-point combined technique for time periodic magnetic field problems with hysteresis

    SciTech Connect

    Chiampi, M.; Repetto, M.; Chiarabaglio, D.

    1995-11-01

    The hysteresis phenomenon can significantly affect the behavior of magnetic cores in electrical machines and devices. This paper presents a finite element solution of periodic steady state magnetic field problems in soft materials with scalar hysteresis. The Jiles-Atherton model is employed for the generation of symmetric B-H loops and it is coupled with the Fixed Point Technique for handling magnetic nonlinearities. The proposed procedure is applied to a hysteretic model problem whose analytical solution is available. The results show that the Fixed Point Technique can efficiently deal with non-single valued material characteristics under periodic operating conditions.

  3. Identification of potential surrogate end points in randomized clinical trials of aggressive and indolent non-Hodgkin's lymphoma: correlation of complete response, time-to-event and overall survival end points

    PubMed Central

    Lee, L.; Wang, L.; Crump, M.

    2011-01-01

    Background: The correlation between efficacy end points in randomized controlled trials (RCTs) of systemic therapy for non-Hodgkin's lymphoma (NHL) was investigated to identify an appropriate surrogate end point for overall survival (OS). Methods: RCTs of previously untreated NHL published from 1990 to 2009 were identified. Associations between absolute differences in efficacy end points were determined using nonparametric Spearman's rank correlation coefficients (rs). Results: Thirty-eight RCTs representing 85 treatment arms for aggressive NHL and 20 RCTs representing 42 arms for indolent NHL were included. For aggressive NHL, differences in 3-year progression-free survival (PFS)/event-free survival (EFS) were high correlated with differences in 5-year OS {rs of 0.90 [95% confidence interval (CI) 0.73–0.96]} and linear regression determined that a 10% improvement in 3-year EFS or PFS would predict for a 7% ± 1% improvement in 5-year OS. For indolent histology disease, differences in complete response were strongly correlated with differences in 3-year EFS [rs 0.86 (95% CI 0.35–0.97)], but there was no correlation between 3-year time-to-event end points and 5-year OS. Conclusions: Improvements in 3-year EFS/PFS are highly correlated with improvements in 5-year OS in aggressive NHL and should be explored as a candidate surrogate end point. Definition of these relationships may inform future clinical trial design and interpretation of interim trial data. PMID:21266519

  4. Estimation of point source fugitive emission rates from a single sensor time series: a conditionally-sampled Gaussian plume reconstruction

    EPA Science Inventory

    This paper presents a technique for determining the trace gas emission rate from a point source. The technique was tested using data from controlled methane release experiments and from measurement downwind of a natural gas production facility in Wyoming. Concentration measuremen...

  5. Estimation of point source fugitive emission rates from a single sensor time series: A conditionally-sampled Gaussian plume reconstruction

    NASA Astrophysics Data System (ADS)

    Foster-Wittig, Tierney A.; Thoma, Eben D.; Albertson, John D.

    2015-08-01

    Emerging mobile fugitive emissions detection and measurement approaches require robust inverse source algorithms to be effective. Two Gaussian plume inverse approaches are described for estimating emission rates from ground-level point sources observed from remote vantage points. The techniques were tested using data from 41 controlled methane release experiments (14 studies) and further investigated using 7 field studies executed downwind of oil and gas well pads in Wyoming. Analyzed measurements were acquired from stationary observation locations 18-106 m downwind of the emission sources. From the fluctuating wind direction, the lateral plume geometry is reconstructed using a derived relationship between the wind direction and crosswind plume position. The crosswind plume spread is determined with both modeled and reconstructed Gaussian plume approaches and estimates of source emission rates are found through inversion. The source emission rates were compared to a simple point source Gaussian emission estimation approach that is part of Draft EPA Method OTM 33A. Compared to the known release rates, the modeled, reconstructed, and point source Gaussian controlled release results yield average percent errors of -5%, -2%, and 6% with standard deviations of 29%, 25%, and 37%, respectively. Compared to each other, the three methods agree within 30% for 78% of all 48 observations (41 CR and 7 Wyoming).

  6. Real-time attitude commanding to detect coverage gaps and generate high resolution point clouds for RSO shape characterization with a laser rangefinder

    NASA Astrophysics Data System (ADS)

    Nayak, M.; Beck, J.; Udrea, B.

    This paper expands on previous studies by the authors into 3D imaging with a single-beam laser rangefinder (LRF) by implementing real-time attitude maneuvers of a chaser satellite flying in relative orbit around a resident space object (RSO). Point clouds generated with an LRF are much sparser than those generated with an imaging LIDAR, making it difficult to autonomously distinguish between gaps in coverage and truly empty space. Furthermore, if both the attitude and the shape of the target RSO are unknown, it is particularly difficult to register a collection of LRF strike points together and detect gaps in strike point coverage in realtime. This paper presents the incorporation of a narrow field of-view (NFOV) camera that detects the strike point on the RSO and supplements LRF distance measurements with image data. This data is used to generate attitude command profiles that efficiently fill LRF coverage gaps and generate high density point clouds, thus maximizing coverage of an unknown RSO. Results obtained so far point the way to a real-time implementation of the algorithm. A method to detect and close gaps in LRF strike point coverage is presented first. Coverage gap detection is achieved using Voronoi diagrams, where Voronoi cells are centered at the LRF strike points. A three-part algorithm is used that 1) creates a 3D panoramic map from “ stitched” NFOV camera images; 2) correlates the areas of sparse LRF coverage to the map; and 3) generates attitude commands to close the coverage gaps. The map provides a consistent and reliable method to register positions of strike points relative to each other and to the NFOV image of the RSO without a priori knowledge of the RSO attitude. Using this algorithm, gaps and sparse areas in LRF coverage are covered with strike points, allowing for the generation of a higher-resolution point cloud than that obtained with preprogrammed attitude profiles. Attitude maneuvers can now be designed on-line in real-ti- e such

  7. Effects of Varying Epoch Lengths, Wear Time Algorithms, and Activity Cut-Points on Estimates of Child Sedentary Behavior and Physical Activity from Accelerometer Data

    PubMed Central

    Banda, Jorge A.; Haydel, K. Farish; Davila, Tania; Desai, Manisha; Haskell, William L.; Matheson, Donna; Robinson, Thomas N.

    2016-01-01

    Objective To examine the effects of accelerometer epoch lengths, wear time (WT) algorithms, and activity cut-points on estimates of WT, sedentary behavior (SB), and physical activity (PA). Methods 268 7–11 year-olds with BMI ≥ 85th percentile for age and sex wore accelerometers on their right hips for 4–7 days. Data were processed and analyzed at epoch lengths of 1-, 5-, 10-, 15-, 30-, and 60-seconds. For each epoch length, WT minutes/day was determined using three common WT algorithms, and minutes/day and percent time spent in SB, light (LPA), moderate (MPA), and vigorous (VPA) PA were determined using five common activity cut-points. ANOVA tested differences in WT, SB, LPA, MPA, VPA, and MVPA when using the different epoch lengths, WT algorithms, and activity cut-points. Results WT minutes/day varied significantly by epoch length when using the NHANES WT algorithm (p < .0001), but did not vary significantly by epoch length when using the ≥ 20 minute consecutive zero or Choi WT algorithms. Minutes/day and percent time spent in SB, LPA, MPA, VPA, and MVPA varied significantly by epoch length for all sets of activity cut-points tested with all three WT algorithms (all p < .0001). Across all epoch lengths, minutes/day and percent time spent in SB, LPA, MPA, VPA, and MVPA also varied significantly across all sets of activity cut-points with all three WT algorithms (all p < .0001). Conclusions The common practice of converting WT algorithms and activity cut-point definitions to match different epoch lengths may introduce significant errors. Estimates of SB and PA from studies that process and analyze data using different epoch lengths, WT algorithms, and/or activity cut-