Short duration flares in GALEX data

NASA Astrophysics Data System (ADS)

Brasseur, Clara; Osten, Rachel A.

2018-06-01

Flares on cool stars indicate short time-scale magnetic reconnection processes that provide temporary increases in the stellar radiative output. While recent work has focused on long-duration flares from solar-like stars and those of lower mass, the existence of short-duration flares in the ultraviolet has not been systematically probed before. We will present an interesting population of short duration flares we discovered in a sample of ~37,000 light curves observed from 2009-2012 by the GALEX and Kepler missions. These flares range in duration from under a minute to a few minutes and are almost entirely distinct from a previous flare survey of Kepler data. We were able to detect this unique population of flares because the time resolution of the GALEX data allowed us to construct light curves with a 10 second cadence and thus detect shorter duration flares than could be detected within Kepler data. We applied algorithmic flare detection to a sample of ~37,000 stars, and identified a final count of 2,065 flares on 1,121 stars. We discuss the implication of these events for the flare frequency distributions of solar-like stars.

Indirect ignition of energetic materials with laser-driven flyer plates.

PubMed

Dean, Steven W; De Lucia, Frank C; Gottfried, Jennifer L

2017-01-20

The impact of laser-driven flyer plates on energetic materials CL-20, PETN, and TATB has been investigated. Flyer plates composed of 25 μm thick Al were impacted into the energetic materials at velocities up to 1.3 km/s. The flyer plates were accelerated by means of an Nd:YAG laser pulse. The laser pulse generates rapidly expanding plasma between the flyer plate foil and the substrate to which it is adhered. As the plasma grows, a section of the metal foil is ejected at high speed, forming the flyer plate. The velocity of the flyer plate was determined using VISAR, time of flight, and high-speed video. The response of the energetic material to impact was determined by light emission recorded by an infrared-sensitive photodiode. Following post-impact analysis of the impacted energetic material, it was hypothesized that the light emitted by the material after impact is not due to the impact of the flyer itself but rather is caused by the decomposition of energetic material ejected (via the shock of flyer plate impact) into a cloud of hot products generated during the launch of the flyer plate. This hypothesis was confirmed through schlieren imaging of a flyer plate launch, clearly showing the ejection of hot gases and particles from the region surrounding the flyer plate launch and the burning of the ejected energetic material particles.

Association between self-reported sleep duration and dietary quality in European adolescents.

PubMed

Bel, Sarah; Michels, Nathalie; De Vriendt, Tineke; Patterson, Emma; Cuenca-García, Magdalena; Diethelm, Katharina; Gutin, Bernard; Grammatikaki, Evangelia; Manios, Yannis; Leclercq, Catherine; Ortega, Francisco B; Moreno, Luis A; Gottrand, Frederic; Gonzalez-Gross, Marcela; Widhalm, Kurt; Kafatos, Anthony; Garaulet, Marta; Molnar, Denes; Kaufman, Jean-Marc; Gilbert, Chantal C; Hallström, Lena; Sjöström, Michael; Marcos, Ascensión; De Henauw, Stefaan; Huybrechts, Inge

2013-09-14

Evidence has grown supporting the role for short sleep duration as an independent risk factor for weight gain and obesity. The purpose of the present study was to examine the relationship between sleep duration and dietary quality in European adolescents. The sample consisted of 1522 adolescents (aged 12.5-17.5 years) participating in the European multi-centre cross-sectional ‘Healthy Lifestyle in Europe by Nutrition in Adolescence’ study. Sleep duration was estimated by a self-reported questionnaire. Dietary intake was assessed by two 24 h recalls. The Diet Quality Index for Adolescents with Meal index (DQI-AM) was used to calculate overall dietary quality, considering the components dietary equilibrium, dietary diversity, dietary quality and a meal index. An average sleep duration of ≥ 9 h was classified as optimal, between 8 and 9 h as borderline insufficient and < 8 h as insufficient. Sleep duration and the DQI-AM score were positively associated (β = 0.027, r 0.130, P< 0.001). Adolescents with insufficient (62.05 (sd 14.18)) and borderline insufficient sleep (64.25 (sd 12.87)) scored lower on the DQI-AM than adolescents with an optimal sleep duration (64.57 (sd 12.39)) (P< 0.001; P= 0.018). The present study demonstrated in European adolescents that short sleep duration was associated with a lower dietary quality. This supports the hypothesis that the health consequences of insufficient sleep may be mediated by the relationship of insufficient sleep to poor dietary quality.

Short Sleep Duration and Dietary Intake: Epidemiologic Evidence, Mechanisms, and Health Implications12

PubMed Central

Dashti, Hassan S; Scheer, Frank AJL; Jacques, Paul F; Lamon-Fava, Stefania; Ordovás, José M

2015-01-01

Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mediated through changes in dietary intake. This review provides an overview of recent epidemiologic studies on the relations between habitual short sleep duration and dietary intake in adults from 16 cross-sectional studies. The studies have observed consistent associations between short sleep duration and higher total energy intake and higher total fat intake, and limited evidence for lower fruit intake, and lower quality diets. Evidence also suggests that short sleepers may have irregular eating behavior deviating from the traditional 3 meals/d to fewer main meals and more frequent, smaller, energy-dense, and highly palatable snacks at night. Although the impact of short sleep duration on dietary intake tends to be small, if chronic, it may contribute to an increased risk of obesity and related chronic disease. Mechanisms mediating the associations between sleep duration and dietary intake are likely to be multifactorial and include differences in the appetite-related hormones leptin and ghrelin, hedonic pathways, extended hours for intake, and altered time of intake. Taking into account these epidemiologic relations and the evidence for causal relations between sleep loss and metabolism and cardiovascular function, health promotion strategies should emphasize improved sleep as an additional factor in health and weight management. Moreover, future sleep interventions in controlled studies and sleep extension trials in chronic short sleepers are imperative for establishing whether there is a causal relation between short sleep duration and changes in dietary intake. PMID:26567190

Sleep Quality and Nocturnal Sleep Duration in Pregnancy and Risk of Gestational Diabetes Mellitus.

PubMed

Cai, Shirong; Tan, Sara; Gluckman, Peter D; Godfrey, Keith M; Saw, Seang-Mei; Teoh, Oon Hoe; Chong, Yap-Seng; Meaney, Michael J; Kramer, Michael S; Gooley, Joshua J

2017-02-01

To examine the influence of maternal sleep quality and nocturnal sleep duration on risk of gestational diabetes mellitus (GDM) in a multiethnic Asian population. A cohort of 686 women (376 Chinese, 186 Malay, and 124 Indian) with a singleton pregnancy attended a clinic visit at 26-28 weeks of gestation as part of the Growing Up in Singapore Towards healthy Outcomes mother-offspring cohort study. Self-reported sleep quality and sleep duration were assessed using the Pittsburgh Sleep Quality Index (PSQI). GDM was diagnosed based on a 75-g oral glucose tolerance test administered after an overnight fast (1999 WHO criteria). Multiple logistic regression was used to model separately the associations of poor sleep quality (PSQI score > 5) and short nocturnal sleep duration (<6 h) with GDM, adjusting for age, ethnicity, maternal education, body mass index, previous history of GDM, and anxiety (State-Trait Anxiety Inventory score). In the cohort 296 women (43.1%) had poor sleep quality and 77 women (11.2%) were categorized as short sleepers; 131 women (19.1%) were diagnosed with GDM. Poor sleep quality and short nocturnal sleep duration were independently associated with increased risk of GDM (poor sleep, adjusted odds ratio [OR] = 1.75, 95% confidence interval [CI] 1.11 to 2.76; short sleep, adjusted OR = 1.96, 95% CI 1.05 to 3.66). During pregnancy, Asian women with poor sleep quality or short nocturnal sleep duration exhibited abnormal glucose regulation. Treating sleep problems and improving sleep behavior in pregnancy could potentially reduce the risk and burden of GDM. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Short term outcomes of long duration versus short duration tourniquet in primary total knee arthroplasty: A randomized controlled trial.

PubMed

Vaishya, Raju; Agarwal, Amit Kumar; Vijay, Vipul; Tiwari, Manish Kumar

2018-01-01

A tourniquet is used during the total knee replacement surgery to improve the visibility, to reduce the blood loss and for better cementation. Indirectly it decreases the duration of surgery and enhances the recovery of the patient. Their use however is controversial due to some side effects associated with the use of tourniquet. They may increase the risk of deep vein thrombosis and pulmonary embolism by causing venous stasis, endothelial damage and increased platelet adhesion secondary to distal limb ischemia. We conducted a randomized controlled trial (RCT) to examine the benefits and risks associated with the use of long duration over short duration tourniquets during TKA. The study was a prospective randomised control trial with a total of 80 knees (40 knees in each group) included in the study. The knees selected for surgery were randomly allocated to one of the two groups: Group A - long duration tourniquet (LT-group) or Group B - short duration tourniquet (ST-group). The average operating time in Group A (43.53±3.11 minutes) was statistically less significant than that of Group B (51.7±2.56 minutes). Intra-operative blood loss in Group B, was significantly more than that of Group A. Post-operative blood loss in the drain was more in long duration tourniquet group. Total blood loss (intra-operative + post-operative) was more in short duration tourniquet group. Pain score (using VAS scale) was comparable in both the groups at the end of the second and sixth week. At sixth weeks there was no significant difference in the range of motion in both the groups. The KSS score was not significantly different in both the groups in post operative period at first, second, and six weeks. There were no events of thrombo-embolism and deep vein thrombosis in either groups. In 11 patients (27.5%) of long duration tourniquet group, swelling, and redness of knee was seen post operatively as compared to three patients (7.5%) of short duration tourniquet group. The use of a

Laser-launched flyers with organic working fluids

NASA Astrophysics Data System (ADS)

Mulford, Roberta; Swift, Damian

2003-10-01

The TRIDENT laser has been used to launch flyers by depositing IR energy in a thin layer of material - the working fluid - sandwiched between the flyer and a transparent substrate. We have investigated the use of working fluids based on organics, chosen as they are quite efficient absorbers of IR energy and should also convert heat to mechanical work more efficiently than materials such as carbon. A thermodynamically complete equation of state was developed for one of the fluids investigated experimentally - a carbohydrate solution - by chemical equilibrium calculations using the CHEETAH program. Continuum mechanics simulations were made of the flyer launch process, modeling the effect of the laser as energy deposition in the working fluid, and taking into account the compression and recoil of the substrate. We compare the simulations with a range of experiments and demonstrate the optimization of substrate and fluid thickness for a given flyer thickness and speed.

Apparatus and method for explosive bonding to edge of flyer plate

NASA Technical Reports Server (NTRS)

Bement, Laurence J. (Inventor); Kushnick, Anne C. (Inventor)

1991-01-01

The invention is an apparatus and a process for the explosive joining of a flyer plate and a base plate. The apparatus consists of a flyer plate positioned over a base plate. The flyer plate has a notch containing a filler material in intimate contact with the flyer plate. An adhesive means holds a ribbon explosive partially overlapping the notch in the flyer plate. A detonating means initiates the ribbon explosive that drives the flyer plate to accomplish a high velocity, angular collision between the mating surfaces. This collision creates surface melts and effacing bonding, resulting in electron sharing linkups between the plates. An unbonded tab fractures at a base of the notch leaving a bond to an edge of the attached flyer plate.

Fiber optic mounted laser driven flyer plates

DOEpatents

Paisley, Dennis L.

1991-01-01

A laser driven flyer plate where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs.

Laser energy transformation to shock waves in multi-layer flyers

NASA Astrophysics Data System (ADS)

Kasperczuk, A.; Pisarczyk, T.; Gus'kov, S. Yu.; Ullschmied, J.; Krouský, E.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Kalal, M.; Tikhonchuk, V.; Pisarczyk, P.

Investigations of powerful laser pulse action on planar flyer targets consisting of the layers of different materials are of importance from the basic as well as the applied physics point of view. One important aspect of this research deals with optimization of inertial fusion targets design. Here, the role of a thin heavy metal layer as a protector against preliminary heating of compressed thermonuclear fuel by thermal X-ray radiation can be mentioned as one particular topic to be properly understood. In this paper, the results of our studies of such a thin layer influence on the laser-produced energy deposition in the flyer foils as well as on the hydrodynamic motion of the foils as a hole will be reported. A 0.4 μ m thick gold layer was located between an aluminum layer of 6 μ m thickness and mylar layer with thickness of 2.5 μ m, used here as an ablator. For comparison, the flyer target without the gold layer but of the same area density was employed. Two different target constructions were used: (1) with a 2 mm gap separating the foil and the massive targets for measuring the foil velocity and (2) with gaps of 50, 100 and 200 μ m for laser energy transfer efficiency measurements. Targets were irradiated by laser beam energies of ˜100 J in the case of the first harmonic, and by laser beam energies ˜120 J in the case of the third one using the Prague Asterix Laser System iodine laser. The interaction spot radius of 200 μ m and the laser pulse duration of ˜250 ps were employed in these experiments. A three-frame interferometric and shadowgraphic system was set-up as to measure velocities of the rear side of the foils and to determine electron density distributions at different stages of plasma evolution. Volumes of craters produced by collisions of accelerated foils with a massive aluminum block were used as an indicator of the laser energy transfer efficiency into the foils of both types. These experiments have shown that the presence of the thin gold

Short sleep duration among workers--United States, 2010.

PubMed

2012-04-27

Insufficient sleep can have serious and sometimes fatal consequences for fatigued workers and others around them. For example, an estimated 20% of vehicle crashes are linked to drowsy driving. The National Sleep Foundation recommends that healthy adults sleep 7-9 hours per day. To assess the prevalence of short sleep duration among workers, CDC analyzed data from the 2010 National Health Interview Survey (NHIS). The analysis compared sleep duration by age group, race/ethnicity, sex, marital status, education, and employment characteristics. Overall, 30.0% of civilian employed U.S. adults (approximately 40.6 million workers) reported an average sleep duration of ≤6 hours per day. The prevalence of short sleep duration (≤6 hours per day) varied by industry of employment (range: 24.1%-41.6%), with a significantly higher rate of short sleep duration among workers in manufacturing (34.1%) compared with all workers combined. Among all workers, those who usually worked the night shift had a much higher prevalence of short sleep duration (44.0%, representing approximately 2.2 million night shift workers) than those who worked the day shift (28.8%, representing approximately 28.3 million day shift workers). An especially high prevalence of short sleep duration was reported by night shift workers in the transportation and warehousing (69.7%) and health-care and social assistance (52.3%) industries. Targeted interventions, such as evidence-based shift system designs that improve sleep opportunities and evidence-based training programs on sleep and working hours tailored for managers and employees, should be implemented to protect the health and safety of workers, their coworkers, and the public.

Note: Heated flyer-plate impact system

NASA Astrophysics Data System (ADS)

Dolan, D. H.; Seagle, C. T.; Ao, T.; Hacking, R. G.

2014-07-01

A technique for launching heated flyer plates was developed on a single-stage gas gun. This type of impact creates a well-posed mechanical state and a tunable thermal state, which is useful for calibrating dynamic temperature measurements. Proof-of-principle thermoreflectance measurements were performed using this technique. Since the target remains at room temperature until the moment of impact, heated flyers avoid differential expansion and annealing issues, allowing novel impact experiments to be performed.

Note: Heated flyer-plate impact system.

PubMed

Dolan, D H; Seagle, C T; Ao, T; Hacking, R G

2014-07-01

A technique for launching heated flyer plates was developed on a single-stage gas gun. This type of impact creates a well-posed mechanical state and a tunable thermal state, which is useful for calibrating dynamic temperature measurements. Proof-of-principle thermoreflectance measurements were performed using this technique. Since the target remains at room temperature until the moment of impact, heated flyers avoid differential expansion and annealing issues, allowing novel impact experiments to be performed.

Short sleep duration and poor sleep quality predict next-day suicidal ideation: an ecological momentary assessment study.

PubMed

Littlewood, Donna L; Kyle, Simon D; Carter, Lesley-Anne; Peters, Sarah; Pratt, Daniel; Gooding, Patricia

2018-04-26

Sleep problems are a modifiable risk factor for suicidal thoughts and behaviors. Yet, sparse research has examined temporal relationships between sleep disturbance, suicidal ideation, and psychological factors implicated in suicide, such as entrapment. This is the first in-the-moment investigation of relationships between suicidal ideation, objective and subjective sleep parameters, and perceptions of entrapment. Fifty-one participants with current suicidal ideation completed week-long ecological momentary assessments. An actigraph watch was worn for the duration of the study, which monitored total sleep time, sleep efficiency, and sleep latency. Daily sleep diaries captured subjective ratings of the same sleep parameters, with the addition of sleep quality. Suicidal ideation and entrapment were measured at six quasi-random time points each day. Multi-level random intercept models and moderation analyses were conducted to examine the links between sleep, entrapment, and suicidal ideation, adjusting for anxiety and depression severity. Analyses revealed a unidirectional relationship whereby short sleep duration (both objective and subjective measures), and poor sleep quality, predicted the higher severity of next-day suicidal ideation. However, there was no significant association between daytime suicidal ideation and sleep the following night. Sleep quality moderated the relationship between pre-sleep entrapment and awakening levels of suicidal ideation. This is the first study to report night-to-day relationships between sleep disturbance, suicidal ideation, and entrapment. Findings suggest that sleep quality may alter the strength of the relationship between pre-sleep entrapment and awakening suicidal ideation. Clinically, results underscore the importance of assessing and treating sleep disturbance when working with those experiencing suicidal ideation.

Short Duration Emergency Incidents Managed as Projects

NASA Astrophysics Data System (ADS)

Nixon, Thomas J.

Emergency incidents have historically been managed by experience and some directional principles usually found in SOPs/SOGs or other pre-incident planning documents. The use of experience has the risk of bias influencing the decisions being made in truly life or death situations. Responders of disasters, long duration emergency incidents, are often equipped with a framework adapted to the project management lifecycle to assure the project priorities are adequately addressed. The disaster framework provides for savings from risk, loss, waste. This research is demonstrating the ability and reasoning to develop a framework to address short duration emergency incidents and expand the events that can be managed as a project. The research of the literature found that a framework can be applied to the project management lifecycle and the priorities of a short duration emergency incident can be managed as a project. The limitations of not having the ability to conduct empirical testing and the risks of not developing a formal implementation plan are discussed. Short duration emergency incidents are found to be capable of being managed as projects and will benefit from the effectiveness of project management methodologies.

Bistable flapping of flexible flyers in oscillatory flow

NASA Astrophysics Data System (ADS)

Huang, Yangyang; Kanso, Eva

2016-11-01

Biological and bio-inspired flyers move by shape actuation. The direct control of shape variables for locomotory purposes is well studied. Less is known about indirect shape actuation via the fluid medium. Here, we consider a flexible Λ-flyer in oscillatory flow that is free to flap and rotate around its fixed apex. We study its motion in the context of the inviscid vortex sheet model. We first analyze symmetric flapping about the vertical axis of gravity. We find that there is a finite value of the flexibility that maximizes both the flapping amplitude and elastic energy storage. Our results show that rather than resonance, the flyer relies on fluidic effects to optimize these two quantities. We then perturb the flyer away from the vertical and analyze its stability. Four distinct types of rolling behavior are identified: mono-stable, bistable, bistable oscillatory rotations and chaotic dynamics. We categorize these types of behavior in terms of the flyer's and flow parameters. In particular, the transition from mono-stable to bistable behavior occurs at a constant value of the product of the flow amplitude and acceleration. This product can be interpreted as the ratio of fluidic drag to gravity, confirming the fluid role in this transition.

Ionizing radiation measurements on LDEF: A0015 Free flyer biostack experiment

NASA Technical Reports Server (NTRS)

Benton, E. V.; Frank, A. L.; Benton, E. R.; Csige, I.; Frigo, L. A.

1995-01-01

This report covers the analysis of passive radiation detectors flown as part of the A0015 Free Flyer Biostack on LDEF (Long Duration Exposure Facility). LET (linear energy transfer) spectra and track density measurements were made with CR-39 and Polycarbonate plastic nuclear track detectors. Measurements of total absorbed dose were carried out using Thermoluminescent Detectors. Thermal and resonance neutron dose equivalents were measured with LiF/CR-39 detectors. High energy neutron and proton dose equivalents were measured with fission foil/CR-39 detectors.

Association between Visual Impairment and Low Vision and Sleep Duration and Quality among Older Adults in South Africa.

PubMed

Peltzer, Karl; Phaswana-Mafuya, Nancy

2017-07-19

This study aims to estimate the association between visual impairment and low vision and sleep duration and poor sleep quality in a national sample of older adults in South Africa. A national population-based cross-sectional Study of Global Ageing and Adults Health (SAGE) wave 1 was conducted in 2008 with a sample of 3840 individuals aged 50 years or older in South Africa. The interviewer-administered questionnaire assessed socio-demographic characteristics, health variables, sleep duration, quality, visual impairment, and vision. Results indicate that 10.0% of the sample reported short sleep duration (≤5 h), 46.6% long sleep (≥9 h), 9.3% poor sleep quality, 8.4% self-reported and visual impairment (near and/or far vision); and 43.2% measured low vision (near and/or far vision) (0.01-0.25 decimal) and 7.5% low vision (0.01-0.125 decimal). In fully adjusted logistic regression models, self-reported visual impairment was associated with short sleep duration and poor sleep quality, separately and together. Low vision was only associated with long sleep duration and poor sleep quality in unadjusted models. Self-reported visual impairment was related to both short sleep duration and poor sleep quality. Population data on sleep patterns may want to include visual impairment measures.

Short pulse duration shock initiation experiments plus ignition and growth modeling on Composition B

NASA Astrophysics Data System (ADS)

May, Chadd M.; Tarver, Craig M.

2014-05-01

Composition B (63% RDX, 36% TNT, 1% wax) is still a widely used energetic material whose shock initiation characteristics are necessary to understand. It is now possible to shock initiate Composition B and other secondary explosives at diameters well below their characteristic failure diameters for unconfined self-sustaining detonation. This is done using very high velocity, very thin, small diameter flyer plates accelerated by electric or laser power sources. Recently experimental detonation versus failure to detonate threshold flyer velocity curves for Composition B using several KaptonTM flyer thicknesses and diameters were measured. Flyer plates with diameters of 2 mm successfully detonated Composition B, which has a nominal failure diameter of 4.3 mm. The shock pressures required for these initiations are greater than the Chapman-Jouguet (C-J) pressure in self-sustaining Composition B detonation waves. The initiation process is two-dimensional, because both rear and side rarefactions can affect the shocked Composition B reaction rates. The Ignition and Growth reactive flow model for Composition B is extended to yield accurate simulations of this new threshold velocity data for various flyer thicknesses.

Sleep Duration and White Matter Quality in Middle-Aged Adults

PubMed Central

Yaffe, Kristine; Nasrallah, Ilya; Hoang, Tina D.; Lauderdale, Diane S.; Knutson, Kristen L.; Carnethon, Mercedes R.; Launer, Lenore J.; Lewis, Cora E.; Sidney, Stephen

2016-01-01

Study Objectives: Sleep duration has been associated with risk of dementia and stroke, but few studies have investigated the relationship between sleep duration and brain MRI measures, particularly in middle age. Methods: In a prospective cohort of 613 black and white adults (mean age = 45.4 years) enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study, participants reported typical sleep duration, dichotomized into moderate sleep duration (> 6 to ≤ 8 h) and short sleep duration (≤ 6 h) at baseline (2005–2006). Five years later, we obtained brain MRI markers of white matter including fractional anisotropy, mean diffusivity, and white matter hyperintensities. Results: Compared to moderate sleepers, short sleepers had an elevated ratio of white matter hyperintensities to normal tissue in the parietal region (OR = 2.31, 95% CI: 1.47, 3.61) adjusted for age, race/sex, education, hypertension, stroke/TIA, depression, smoking status, and physical activity. White matter diffusivity was also higher, approximately a 0.2 standard deviation difference, in frontal, parietal, and temporal white matter regions, among those reporting shorter sleep duration in (P < 0.05 for all). Conclusions: Short sleep duration was associated with worse markers of white matter integrity in midlife. These mid-life differences in white matter may underlie the link between poor sleep and risk of dementia and stroke. Citation: Yaffe K, Nasrallah I, Hoang TD, Lauderdale DS, Knutson KL, Carnethon MR, Launer LJ, Lewis CE, Sidney S. Sleep duration and white matter quality in middle-aged adults. SLEEP 2016;39(9):1743–1747. PMID:27397561

[Interaction between quality and duration of sleep on the prevalence of type 2 diabetes].

PubMed

Zhang, Pan; Lou, Peian; Chang, Guiqiu; Zhang, Lei; Chen, Peipei; Li, Ting; Qiao, Cheng; Dong, Zongmei

2014-09-01

To explore the effects related to quality and duration of sleep and their interactions on the prevalence of type-2 diabetes (T2DM). 9 622 people aged 18 years and over were recruited for our cross-sectional study during March 2013 to May 2013. Unconditional logistic regression was used to analyze the relationship between quality and duration of sleep on T2DM. Bootstrap was used to calculate the relative excess risk of interaction (RERI), the attributable proportion (AP) of interaction and the synergy index (SI). 95% confidence intervals (CI) of RERI, AP and SI were estimated. Concerning the comparison between cases and controls on both individual and total scores, other scores were all significantly different (P < 0.01), except for two items (time for falling asleep and drugs for hypnosis). The prevalence of T2DM in volunteers with poor sleeping quality was higher than that in volunteers with good sleeping quality (P < 0.01). Individuals with sleep duration <6 hours had a higher prevalence of T2DM, when compared with individuals with sleep duration of 6-8 hours (P < 0.01). After adjusting for age, gender, level of education, occupation, family history of diabetes, status on cigarette smoking, alcohol intake, physical activities and body mass index (BMI), the prevalence of T2DM appeared the highest in those with poor sleeping quality and short duration (OR = 4.78, 95% CI:3.32-6.99; P < 0.01), when compared with those who had good sleep quality and 6-8 h sleep duration. The risk of T2DM still increased in people who had poor sleep or long duration (OR = 1.92, 95% CI:1.18-3.31; P < 0.01). Values of RERI, AP and SI (with 95% CI) were 2.33 (1.23-8.79), 0.67(0.21-0.83) and 6.87 (2.33-10.75), respectively, for the interaction between poor sleep quality and short sleep duration, while 0.33 (-0.12-1.13), 0.17 (-0.03-0.51), 1.56 (0.76-2.74) for the interaction between good sleep quality and long sleep duration. Our results suggested that there were additive interactions

High-speed laser-launched flyer impacts studied with ultrafast photography and velocimetry

DOE PAGES

Banishev, Alexandr A.; Shaw, William L.; Bassett, Will P.; ...

2016-02-16

Pulsed lasers can launch thin metal foils at km s -1, but for precision measurements in shock compression science and shock wave spectroscopy, where one-dimensional shock compression is vital, flyer plate impacts with targets must have a high degree of flatness and minimal tilt, and the flyer speeds and impact times at the target must be highly reproducible. We have developed an apparatus that combines ultrafast stroboscopic optical microscopy with photon Doppler velocimetry to study impacts of laser-launched Al and Cu flyer plates with flat, transparent glass targets. The flyer plates were 0.5 mm in diameter, and ranged from 12-100more » μm thick, with flyer speeds up to 6.25 km s -1. The velocity variations over 30-60 launches from the same flyer plate optic can be as low as 0.6%, and the impact time variations can be as low as 0.8 ns. Stroboscopic image streams (reconstructed movies) show uniform, flat impacts with a glass target. As a result, these stroboscopic images can be used to estimate the tilt in the flyer-target impact to be <1mrad.« less

Associations between sleep duration, sleep quality and diabetic retinopathy.

PubMed

Tan, Nicholas Y Q; Chew, Merwyn; Tham, Yih-Chung; Nguyen, Quang Duc; Yasuda, Masayuki; Cheng, Ching-Yu; Wong, Tien Yin; Sabanayagam, Charumathi

2018-01-01

Abnormal durations of sleep have been associated with risk of diabetes. However, it is not clear if sleep duration is associated with diabetic retinopathy (DR). In a cross-sectional study, we included 1,231 (Malay, n = 395; Indian, n = 836) adults (mean age 64.4 ± 9.0 years, 50.4% female) with diabetes from the second visit of two independent population-based cohort studies (2011-15) in Singapore. Self-reported habitual sleep duration was categorized as short (<6 h), normal (6≤ h <8), and long (≥8 h). Questionnaires were administered to detect risk of obstructive sleep apnea (OSA), excessive daytime sleepiness, and insomnia, all of which may indicate poor quality of sleep. The associations between sleep-related characteristics with moderate DR and vision-threatening DR (VTDR) were analysed using logistic regression models adjusted for potential confounders. Prevalence of moderate DR and VTDR in the study population were 10.5% and 6.3% respectively. The mean duration of sleep was 6.4 ± 1.5 h. Compared to normal sleep duration, both short and long sleep durations were associated with moderate DR with multivariable odds ratio (95% confidence interval) of 1.73 (1.03-2.89) and 2.17 (1.28-3.66) respectively. Long sleep duration (2.37 [1.16-4.89]), high risk of OSA (2.24 [1.09-4.75]), and excessive daytime sleepiness (3.27 [1.02-10.30]) were separately associated with VTDR. Sleep duration had a U-shaped association with moderate DR; long sleep duration, excessive daytime sleepiness and high risk of OSA were positively associated with VTDR.

Portable positive protection : a guide for short duration and short term work zones.

DOT National Transportation Integrated Search

2016-06-01

Transportation agencies, contractors, researchers, and private vendors are actively looking for new methods and devices : to help make construction and maintenance work zones safer while maximizing mobility. Short-term and short-duration : work zones...

Biologically-inspired navigation and flight control for Mars flyer missions

NASA Technical Reports Server (NTRS)

Thakoor, S.; Chahl, J.; Hine, B.; Zornetzer, S.

2003-01-01

Bioinspired Engineering Exploration Systems (BEES), is enabling new bioinspired sensors for autonomous exploration of Mars. The steps towards autonomy in development of these BEES flyers are described. A future set of Mars mission that are uniquely enabled by surch flyers are finally described.

Marked exacerbation of orthostatic intolerance after long- vs. short-duration spaceflight in veteran astronauts.

PubMed

Meck, J V; Reyes, C J; Perez, S A; Goldberger, A L; Ziegler, M G

2001-01-01

The incidence of postflight orthostatic intolerance after short-duration spaceflight is about 20%. However, the incidence after long-duration spaceflight was unknown. The purpose of this study was to test the hypothesis that orthostatic intolerance is more severe after long-duration than after short-duration flight. We performed tilt tests on six astronauts before and after long-duration (129-190 days) spaceflights and compared these data with data obtained during stand tests before and after previous short-duration missions. Five of the six astronauts studied became presyncopal during tilt testing after long-duration flights. Only one had become presyncopal during stand testing after short-duration flights. We also compared the long-duration flight tilt test data to tilt test data from 20 different astronauts who flew on the short-duration Shuttle missions that delivered and recovered the astronauts to and from the Mir Space Station. Five of these 20 astronauts became presyncopal on landing day. Heart rate responses to tilt were no different between astronauts on long-duration flights and astronauts on short-duration flights, but long-duration subjects had lower stroke volumes and cardiac outputs than short-duration presyncopal subjects, suggesting a possible decrease in cardiac contractile function. One subject had subnormal norepinephrine release with upright posture after the long flight but not after the short flight. Plasma volume losses were not greater after long flights. Long-duration spaceflight markedly increases orthostatic intolerance, probably with multiple contributing factors.

An interactive media program for managing psychosocial problems on long-duration spaceflights.

PubMed

Carter, James A; Buckey, Jay C; Greenhalgh, Leonard; Holland, Albert W; Hegel, Mark T

2005-06-01

Space crews must be self-reliant to complete long-duration missions successfully. This project involves the development and evaluation of a network of self-guided interactive multimedia programs to train and assist long-duration flyers in the prevention, assessment, and management of psychosocial problems that can arise on extended missions. The system is currently under development and is intended for use both during training and on orbit. A virtual space station 3-dimensional graphic was created to serve as a portal to multimedia-based training, assessment, and intervention resources. Additionally, original content on interpersonal conflict and depression is being developed for the system. Input on the best practices for managing conflict and depression on extended missions was obtained from 13 veteran long-duration flyers, as well as from clinical experts. Formative evaluation of a prototype of the system will be conducted with 10 members of the astronaut corps. Subsequently, the content on conflict and depression will be completed, and the depression self-treatment portion will be evaluated in a randomized controlled trial. Although this study involves developing countermeasures to assist long-duration flyers, it also provides a model that could be applied in many Earthbound settings, both in operational environments and in everyday life.

Large Area and Short-Pulse Shock Initiation of a Tatb/hmx Mixed Explosive

NASA Astrophysics Data System (ADS)

Guiji, Wang; Chengwei, Sun; Jun, Chen; Cangli, Liu; Jianheng, Zhao; Fuli, Tan; Ning, Zhang

2007-12-01

The large area and short-pulse shock initiation experiments on the plastic bonded mixed explosive of TATB(80%) and HMX(15%) have been performed with an electric gun where a Mylar flyer of 10-19 mm in diameter and 0.05˜0.30 mm in thickness was launched by an electrically exploding metallic bridge foil. The cylindrical explosive specimens (Φ16 mm×8 mm in size) were initiated by the Mylar flyers in thickness of 0.07˜0.20 mm, which induced shock pressure in specimen was of duration ranging from 0.029 to 0.109 μs. The experimental data were treated with the DRM(Delayed Robbins-Monro) procedure and to provide the initiation threshold of flyer velocities at 50% probability are 3.398˜1.713 km/s and that of shock pressure P 13.73˜5.23 GPa, respectively for different pulse durations. The shock initiation criteria of the explosive specimen at 50% and 100% probabilities are yielded. In addition, the 30° wedged sample was tested and the shock to detonation transition (SDT) process emerging on its inclined surface was diagnosed with a device consisting of multiple optical fiber probe, optoelectronic transducer and digital oscilloscope. The POP plot of the explosive has been gained from above SDT data.

Short Sleep Duration in Middle Childhood: Risk Factors and Consequences

PubMed Central

Nixon, Gillian M.; Thompson, John M. D.; Han, Dug Yeo; Becroft, David M.; Clark, Phillipa M.; Robinson, Elizabeth; Waldie, Karen E.; Wild, Chris J.; Black, Peter N.; Mitchell, Edwin A.

2008-01-01

Study Objectives: To measure sleep duration in 7-year-old children; identify the determinants of sleep duration; and assess the association between short sleep duration and obesity, cognitive functioning, and behaviour. Design: Longitudinal study with disproportionate sampling of the participants. Setting: Community. Participants: 591 seven-year-old children, of whom 519 had complete sleep data. Interventions: Not applicable. Measurements: Sleep duration was assessed by actigraphy. Other measurements included height, weight, BMI, percentage body fat as assessed by bioimpedance assay, intelligence (WISC-III) and behaviour (Strengths & Difficulties questionnaire, parent and teachers Conners Rating Scales). Results: Mean time in bed according to parental report was 10.9 hours (SD 0.8). Mean sleep duration by actigraphy was 10.1 (SD 0.8) hours. In multivariable analysis, sleep duration was longer on weekdays vs. weekend nights (31.5 min, P = 0.002), in winter (40.5 min), autumn (31.1 min), and spring (14.8 min) compared with summer (P <0.0001), and in those with younger siblings (11.7 min, P = 0.03). Sleep duration was shorter when bedtime was after 21:00 (−41.1 min, P <0.0001). In multivariable analysis, sleep duration <9 hours was associated with being overweight/obese (BMI: OR = 3.32; 95% CI = 1.40, 7.87) with an increase of 3.34% body fat (P = 0.03), and this was not explained by physical activity or television watching. Short sleep duration was also associated with higher emotional lability scores (Conners Rating Scale Parent Form; P = 0.03). IQ (WISC-III) and attention deficit / hyperactivity disorder scores (both parent and teachers Conners Rating Scales) did not differ with sleep duration. Conclusions: Sleep duration in 7-year-old children varies considerably among individuals. The duration is affected by weekday, season, and having younger siblings. Importantly, short sleep duration was shown to be an independent risk factor for obesity/overweight. Citation

Sleep duration and diet quality among women within 5 years of childbirth in the United States- a cross-sectional study

PubMed Central

Xiao, Rui S.; Simas, Tiffany A. Moore; Pagoto, Sherry L.; Person, Sharina D.; Rosal, Milagros C.; Waring, Molly E.

2016-01-01

Objective Only 9% of women with young children consume a high quality diet. The association between sleep duration and health may be U-shaped. We examined diet quality in relation to sleep duration among U.S. women within 5 years of childbirth. Methods Data were from non-pregnant women aged 20-44 years within 5 years of childbirth who completed two 24-hour dietary recalls (N=896) in the National Health and Nutrition Examination Survey (NHANES) 2005-2012. Self-reported weekday/workday sleep duration was categorized as short (≤6 hours), adequate (7-8 hours), or long (≥9 hours). The Healthy Eating Index (HEI-2010, range: 0-100) estimated overall and components of diet quality. Multivariable-adjusted linear regression models estimated the association between sleep duration and diet quality, adjusting for age, race/ethnicity, and education. Results Thirty-four percent of women reported short, 57.1% adequate, and 8.6% long sleep duration. The average diet quality total score was 47.4 out of 100. Short sleep duration was not associated with diet quality. Long sleep duration was associated with lower quality diet (β = −4.3; 95% CI: −8.1 - −0.4), lower consumption of total fruit (β = −0.7; 95% CI: −1.3 - −0.1), whole fruit (β = −0.9; 95% CI: −1.6 - −0.2), and total protein (β = −0.7; 95% CI: −1.3 - −0.03), and higher consumption of empty calories (β = 2.2; 95% CI: −4.3 - −0.1). Conclusions for Practice Future studies should examine the longitudinal association between sleep duration and diet quality among women following childbirth and whether interventions to improve sleep can enhance diet quality. PMID:27090412

Developing Large Scale Explosively Driven Flyer Experiments on Sand

NASA Astrophysics Data System (ADS)

Rehagen, Thomas; Kraus, Richard

2017-06-01

Measurements of the dynamic behavior of granular materials are of great importance to a variety of scientific and engineering applications, including planetary science, seismology, and construction and destruction. In addition, high quality data are needed to enhance our understanding of granular physics and improve the computational models used to simulate related physical processes. However, since there is a non-negligible grain size associated with these materials, experiments must be of a relatively large scale in order to capture the continuum response of the material and reduce errors associated with the finite grain size. We will present designs for explosively driven flyer experiments to make high accuracy measurements of the Hugoniot of sand (with a grain size of hundreds of microns). To achieve an accuracy of better than a few percent in density, we are developing a platform to measure the Hugoniot of samples several centimeters in thickness. We will present the target designs as well as coupled designs for the explosively launched flyer system. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344.

The Combined Effect of Sleep Duration and Quality on Mental Health Among Republic of Korea Armed Forces.

PubMed

Kim, Tae Kyung; Lee, Hee-Choon; Lee, Sang Gyu; Han, Kyu-Tae; Park, Eun-Cheol

2016-11-01

Sleep problems in the Republic of Korea Armed Forces have increased. This study analyzed the mental health impact of sleep duration and quality on personnel of the Republic of Korea Armed Forces. Data from the 2014 Military Health Survey were used. Degree of sleep duration and quality were measured by this self-reported questionnaire. Analysis of variance was carried out to compare Kessler Psychological Distress Scale 10 (K10) scores. Multiple logistic regression analysis identified associations between sleep duration, quality, and K10 scores. Among the personnel studied, 2.5% reported severe sleep difficulties. The average sleep duration was 6.83 ± 1.12 hours. Short sleep duration and sleep difficulty were associated with poorer K10 scores. Higher K10 scores among individuals with short sleep duration and low sleep quality were identified in the isolated military area group, the over 53 working hours/week group, and the enlisted soldier group. The factors listed were not by themselves associated with poorer mental health scores. Rather, specific workplaces and specific rank groups were more prone to poorer mental health. These results provide helpful information to minimize the negative psychological effects of sleep factors and to promote a sleep problem prevention and management policy. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Interaction of sleep quality and sleep duration on impaired fasting glucose: a population-based cross-sectional survey in China.

PubMed

Lou, Peian; Chen, Peipei; Zhang, Lei; Zhang, Pan; Chang, Guiqiu; Zhang, Ning; Li, Ting; Qiao, Cheng

2014-03-13

To explore the interactions of sleep quality and sleep duration and their effects on impaired fasting glucose (IFG) in Chinese adults. Cross-sectional survey. Community-based investigation in Xuzhou, China. 15 145 Chinese men and women aged 18-75 years old who fulfilled the inclusion criteria. The Pittsburgh Sleep Quality Index was used to produce sleep quality categories of good, common and poor. Fasting blood glucose levels were assessed for IFG. Sleep duration was measured by average hours of sleep per night, with categories of <6, 6-8 and >8 h. The products of sleep and family history of diabetes, obesity and age were added to the logistic regression model to evaluate the addictive interaction and relative excess risk of interaction (RERI) on IFG. The attributable proportion (AP) of the interaction and the synergy index (S) were applied to evaluate the additive interaction of two factors. Bootstrap measures were used to calculate 95% CI of RERI, AP and S. The prevalence of IFG was greatest in those with poor sleep quality and short sleep duration (OR 6.37, 95% CI 4.66 to 8.67; p<0.001) compared with those who had good sleep quality and 6-8 h sleep duration, after adjusting for confounders. After adjusting for potential confounders RERI, AP and S values (and their 95% CI) were 1.69 (0.31 to 3.76), 0.42 (0.15 to 0.61) and 2.85 (2.14 to 3.92), respectively, for the interaction between poor sleep quality and short sleep duration, and 0.78 (0.12 to 1.43), 0.61 (0.26 to 0.87) and -65 (-0.94 to -0.27) for the interaction between good sleep quality and long sleep duration. The results suggest that there are additive interactions between poor sleep quality and short sleep duration.

Comparison of Echocardiographic Measurements Before and After Short and Long Duration Spaceflight

NASA Technical Reports Server (NTRS)

Fritsch-Yelle, Janice M.; South, Donna A.; Wood, Margie L.; Bungo, Michael W.

2000-01-01

Previous echocardiography studies in astronauts before and after short duration (4 - 17 days) missions have demonstrated a decrease in resting left ventricular (LV) stroke volume (SV), but maintained ejection fraction (EF) and cardiac output. Similar studies before and after long duration (129 - 144 days) spaceflight have been rare and their overall results equivocal. The purpose of this work was to compare the echocardiographic measurements (M-mode, 2-D and Doppler) from short duration (n = 13) and long duration (n = 4) crewmembers. Compared to short duration astronauts, long duration crewmembers had a significantly greater percent decrease in EF (+6+/-0.02 vs.-10.5+/-0.03, p = 0.005) and percent fractional shortening (+7+/-0.03 vs. -11+/-0.07, p = 0.0 15), and an increase in LV end systolic volume (-12+/-0.06 vs. +39+/-0.24, p = 0.011). These data suggest a reduction in cardiac function that relates to mission duration. As the changes in blood pressure and circulating blood volume (9% - 12%) are reported to be similar after short and long duration flights, the drop in EF after longer spaceflights is likely due to a decrease in cardiac function rather than altered blood volume.

Pre-diagnostic Sleep Duration and Sleep Quality in Relation to Subsequent Cancer Survival

PubMed Central

Phipps, Amanda I.; Bhatti, Parveen; Neuhouser, Marian L.; Chen, Chu; Crane, Tracy E.; Kroenke, Candyce H.; Ochs-Balcom, Heather; Rissling, Michelle; Snively, Beverly M.; Stefanick, Marcia L.; Treggiari, Miriam M.; Watson, Nathaniel F.

2016-01-01

Study Objectives: Poor sleep quality and short sleep duration have been associated with elevated risk for several cancer types; however, the relationship between sleep and cancer outcomes has not been well characterized. We assessed the association between pre-diagnostic sleep attributes and subsequent cancer survival within the Women's Health Initiative (WHI). Methods: We identified WHI participants in whom a first primary invasive cancer had been diagnosed during follow-up (n = 21,230). Participants provided information on sleep characteristics at enrollment. Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between these pre-diagnostic sleep characteristics and cancer-specific survival for all cancers combined and separately for common cancers. Analyses were adjusted for age, study arm, cancer site, marital status, income, smoking, physical activity, and time to diagnosis. Results: No individual pre-diagnostic sleep characteristics were found to be significantly associated with cancer survival in analyses of all cancer sites combined; however, women who reported short sleep duration (≤ 6 h sleep/night) combined with frequent snoring (≥ 5 nights/w experienced significantly poorer cancer-specific survival than those who reported 7–8 h of sleep/night and no snoring (HR = 1.32, 95% CI: 1.14–1.54). Short sleep duration (HR = 1.46, 95% CI: 1.07–1.99) and frequent snoring (HR = 1.34, 95% CI: 0.98–1.85) were each associated with poorer breast cancer survival; those reporting short sleep combined with frequent snoring combined had substantially poorer breast cancer survival than those reporting neither (HR = 2.14, 95% CI: 1.47–3.13). Conclusions: Short sleep duration combined with frequent snoring reported prior to cancer diagnosis may influence subsequent cancer survival, particularly breast cancer survival. Citation: Phipps AI, Bhatti P, Neuhouser ML, Chen C, Crane TE, Kroenke CH, Ochs-Balcom H

Sleep duration and sleep quality in relation to 12-year cardiovascular disease incidence: the MORGEN study.

PubMed

Hoevenaar-Blom, Marieke P; Spijkerman, Annemieke M W; Kromhout, Daan; van den Berg, Julia F; Verschuren, W M Monique

2011-11-01

We studied sleep duration and sleep quality in relation to cardiovascular disease (CVD) incidence. Dutch population-based cohort study. 20,432 men and women aged 20-65 and with no history of CVD. N/A. Sleep duration and sleep quality were assessed by a self-administered questionnaire. Morbidity data, vital status, and causes of death were obtained through linkage with several national registries. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using Cox proportional hazards models. During 10-15 years of follow-up, 1,486 CVD and 1,148 coronary heart disease (CHD) events occurred. Short sleepers (≤ 6 h) had a 15% higher risk of total CVD (HR: 1.15; 95%CI: 1.00-1.32) and a 23% higher risk of CHD (HR: 1.23 [1.04-1.45]) compared to normal sleepers (7 h) after adjustment for all confounders. Additional adjustment for intermediate biological risk factors attenuated these relative risks to 1.11 (0.97-1.27) for total CVD and to 1.19 (1.00-1.40) for CHD. Short sleepers with poor sleep quality had a 63% higher risk of CVD (HR: 1.63 [1.21-2.19]) and a 79% higher risk of CHD incidence (HR: 1.79 [1.24-2.58]) compared to normal sleepers with good sleep quality, after adjustments for all confounders. We observed no associations between long sleep duration (≥ 9 h) and CVD or CHD incidence. Short sleepers, especially those with poor sleep quality, have an increased risk of total CVD and CHD incidence. Future investigations should not only focus on sleep duration, but should also take sleep quality into account.

Sleep Duration and Diet Quality Among Women Within 5 Years of Childbirth in the United States: A Cross-Sectional Study.

PubMed

Xiao, Rui S; Moore Simas, Tiffany A; Pagoto, Sherry L; Person, Sharina D; Rosal, Milagros C; Waring, Molly E

2016-09-01

Objective Only 9 % of women with young children consume a high quality diet. The association between sleep duration and health may be U-shaped. We examined diet quality in relation to sleep duration among US women within 5 years of childbirth. Methods Data were from non-pregnant women aged 20-44 years within 5 years of childbirth who completed two 24-h dietary recalls (N = 896) in the National Health and Nutrition Examination Survey 2005-2012. Self-reported weekday/workday sleep duration was categorized as short (≤6 h), adequate (7-8 h), or long (≥9 h). The Healthy Eating Index (HEI-2010, range 0-100) estimated overall and components of diet quality. Multivariable-adjusted linear regression models estimated the association between sleep duration and diet quality, adjusting for age, race/ethnicity, and education. Results Thirty-four percent of women reported short, 57.1 % adequate, and 8.6 % long sleep duration. The average diet quality total score was 47.4 out of 100. Short sleep duration was not associated with diet quality. Long sleep duration was associated with lower quality diet (β = -4.3; 95 % CI -8.1 to -0.4), lower consumption of total fruit (β = -0.7; 95 % CI -1.3 to -0.1), whole fruit (β = -0.9; 95 % CI -1.6 to -0.2), and total protein (β = -0.7; 95 % CI -1.3 to -0.03), and higher consumption of empty calories (β = 2.2; 95 % CI -4.3 to -0.1). Conclusions for practice Future studies should examine the longitudinal association between sleep duration and diet quality among women following childbirth and whether interventions to improve sleep can enhance diet quality.

Sleep duration and quality in relation to non-alcoholic fatty liver disease in middle-aged workers and their spouses.

PubMed

Kim, Chan-Won; Yun, Kyung Eun; Jung, Hyun-Suk; Chang, Yoosoo; Choi, Eun-Suk; Kwon, Min-Jung; Lee, Eun-Hyun; Woo, Eui Jeong; Kim, Nan Hee; Shin, Hocheol; Ryu, Seungho

2013-08-01

Although accumulated evidence implies that short sleep duration and poor sleep quality may lead to an altered metabolic milieu, potentially triggering the development of non-alcoholic fatty liver disease (NAFLD), no studies have explored this association. This study sought to examine whether short sleep duration or poor sleep quality is associated with NAFLD in the general population. We assessed sleep duration and quality using the Pittsburgh Sleep Quality Index in 69,463 middle-aged workers and their spouses and carried out biochemical and anthropometric measurements. The presence of fatty liver was determined using ultrasonographic findings. Logistic regression models were used to evaluate the association of sleep duration and quality with NAFLD, after adjusting for potential confounders. After controlling for the relevant confounding factors (age, alcohol intake, smoking, physical activity, systolic blood pressure, education level, marital status, presence of job, sleep apnea, and loud snoring), the adjusted odds ratio (95% confidence interval) for NAFLD comparing sleep duration ≤5 h to the reference (>7h) was 1.28 (1.13-1.44) in men and 1.71 (1.38-2.13) in women. After further adjustments for BMI, this association was not significant in men (OR: 1.03, 95% CI: 0.90-1.19) but remained significant in women (OR: 1.59, 95% CI: 1.23-2.05). The multivariate-adjusted odds ratio comparing participants with poor sleep quality vs. participants with good sleep quality was 1.10 (95% CI 1.02-1.19) and 1.36 (95% CI 1.17-1.59) in men and women, respectively. In the middle-aged, general population, short sleep duration, and poor sleep quality were significantly associated with an increased risk of NAFLD. Prospective studies are required to confirm this association. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

OBPR Free Flyer draft roadmap overview

NASA Technical Reports Server (NTRS)

Israelsson, Ulf

2005-01-01

OBPR Free Flyer Roadmap Purpose is to describe the OBPR research which is enabled by a free flying spacecraft capability To illustrate how research performed on free flying spacecrafts complement current and planned OBPR ISS activities.

Short sleep duration is independently associated with overweight and obesity in Quebec children.

PubMed

Chaput, Jean-Philippe; Lambert, Marie; Gray-Donald, Katherine; McGrath, Jennifer J; Tremblay, Mark S; O'Loughlin, Jennifer; Tremblay, Angelo

2011-01-01

To investigate the association of sleep duration with adiposity and to determine if caloric intake and physical activity mediate this relationship. The Quebec Adiposity and Lifestyle Investigation in Youth (QUALITY) study is an ongoing longitudinal investigation of Caucasian children with at least one obese biological parent. Children (n = 550) with an average age of 9.6 years (SD = 0.9) who provided complete data at baseline were included in the cross-sectional analyses. Objective measures of adiposity (BMI Z-score, waist circumference, percent body fat measured by dual-energy X-ray absorptiometry), sleep duration and physical activity (accelerometer over 7 days), and diet (24-hour food recalls) were collected. Children were categorized into 4 groups according to sleep duration: < 10 hours, 10-10.9 hours, 11-11.9 hours, and > or = 12 hours of sleep per night. We observed a U-shaped relationship between sleep duration and all adiposity indices. None of energy intake, snacking, screen time or physical activity intensity differed significantly between sleep categories. After adjusting for age, sex, Tanner stage, highest educational level of the parents, total annual family income, and parental BMI, only short-duration sleepers (< 10 hours) had an increased odds of overweight/obesity (OR 2.08, 95% CI 1.16-3.67). Addition of total energy intake and physical activity to the model did not change the association substantially (OR 2.05, 95% CI 1.15-3.63). The present study provides evidence that short sleep duration is a risk factor for overweight and obesity in children, independent of potential covariates. These results further emphasize the need to add sleep duration to the determinants of obesity.

Racial Disparities in Short Sleep Duration by Occupation and Industry

PubMed Central

Jackson, Chandra L.; Redline, Susan; Kawachi, Ichiro; Williams, Michelle A.; Hu, Frank B.

2013-01-01

Short sleep duration, which is associated with increased morbidity and mortality, has been shown to vary by occupation and industry, but few studies have investigated differences between black and white populations. By using data from a nationally representative sample of US adult short sleepers (n = 41,088) in the National Health Interview Survey in 2004–2011, we estimated prevalence ratios for short sleep duration in blacks compared with whites for each of 8 industry categories by using adjusted Poisson regression models with robust variance. Participants' mean age was 47 years; 50% were women and 13% were black. Blacks were more likely to report short sleep duration than whites (37% vs. 28%), and the black-white disparity was widest among those who held professional occupations. Adjusted short sleep duration was more prevalent in blacks than whites in the following industry categories: finance/information/real estate (prevalence ratio (PR) = 1.44, 95% confidence interval (CI): 1.30, 1.59); professional/administrative/management (PR = 1.30, 95% CI: 1.18, 1.44); educational services (PR = 1.39, 95% CI: 1.25, 1.54); public administration/arts/other services (PR = 1.30, 95% CI: 1.21, 1.41); health care/social assistance (PR = 1.23, 95% CI: 1.14, 1.32); and manufacturing/construction (PR = 1.14, 95% CI: 1.07, 1.20). Short sleep generally increased with increasing professional responsibility within a given industry among blacks but decreased with increasing professional roles among whites. Our results suggest the need for further investigation of racial/ethnic differences in the work-sleep relationship. PMID:24018914

Racial disparities in short sleep duration by occupation and industry.

PubMed

Jackson, Chandra L; Redline, Susan; Kawachi, Ichiro; Williams, Michelle A; Hu, Frank B

2013-11-01

Short sleep duration, which is associated with increased morbidity and mortality, has been shown to vary by occupation and industry, but few studies have investigated differences between black and white populations. By using data from a nationally representative sample of US adult short sleepers (n = 41,088) in the National Health Interview Survey in 2004-2011, we estimated prevalence ratios for short sleep duration in blacks compared with whites for each of 8 industry categories by using adjusted Poisson regression models with robust variance. Participants' mean age was 47 years; 50% were women and 13% were black. Blacks were more likely to report short sleep duration than whites (37% vs. 28%), and the black-white disparity was widest among those who held professional occupations. Adjusted short sleep duration was more prevalent in blacks than whites in the following industry categories: finance/information/real estate (prevalence ratio (PR) = 1.44, 95% confidence interval (CI): 1.30, 1.59); professional/administrative/management (PR = 1.30, 95% CI: 1.18, 1.44); educational services (PR = 1.39, 95% CI: 1.25, 1.54); public administration/arts/other services (PR = 1.30, 95% CI: 1.21, 1.41); health care/social assistance (PR = 1.23, 95% CI: 1.14, 1.32); and manufacturing/construction (PR = 1.14, 95% CI: 1.07, 1.20). Short sleep generally increased with increasing professional responsibility within a given industry among blacks but decreased with increasing professional roles among whites. Our results suggest the need for further investigation of racial/ethnic differences in the work-sleep relationship.

Interaction of Sleep Duration and Sleep Quality on Hypertension Prevalence in Adult Chinese Males.

PubMed

Lu, Kai; Chen, Jia; Wu, Shouling; Chen, Ji; Hu, Dayi

2015-01-01

Previous studies demonstrated conflicting results about the association of sleep duration and hypertension. Given the potential relationship between sleep quality and hypertension, this study aimed to investigate the interaction of self-reported sleep duration and sleep quality on hypertension prevalence in adult Chinese males. We undertook a cross-sectional analysis of 4144 male subjects. Sleep duration were measured by self-reported average sleep time during the past month. Sleep quality was evaluated using the standard Pittsburgh Sleep Quality Index. Hypertension was defined as blood pressure level ≥140/90 mm Hg or current antihypertensive treatment. The association between hypertension prevalence, sleep duration, and sleep quality was analyzed using logistic regression after adjusting for basic cardiovascular characteristics. Sleep duration shorter than 8 hours was found to be associated with increased hypertension, with odds ratios and 95% confidence intervals (CIs) of 1.25 (95% CI, 1.03-1.52) for 7 hours, 1.41 (95% CI, 1.14-1.73) for 6 hours, and 2.38 (95% CI, 1.81-3.11) for <6 hours. Using very good sleep quality as the reference, good, poor, and very poor sleep quality were associated with hypertension, with odds ratios of 1.20 (95% CI, 1.01-1.42), 1.67 (95% CI, 1.32-2.11), and 2.32 (95% CI, 1.67-3.21), respectively. More importantly, further investigation of the association of different combinations of sleep duration and quality in relation to hypertension indicated an additive interaction. There is an additive interaction of poor sleep quality and short sleep duration on hypertension prevalence. More comprehensive measurement of sleep should be performed in future studies.

Sensitivity Characterization of Pressed Energetic Materials using Flyer Plate Mesoscale Simulations

NASA Astrophysics Data System (ADS)

Rai, Nirmal; Udaykumar, H. S.

Heterogeneous energetic materials like pressed explosives have complicated microstructure and contain various forms of heterogeneities such as pores, micro-cracks, energetic crystals etc. It is widely accepted that the presence of these heterogeneities can affect the sensitivity of these materials under shock load. The interaction of shock load with the microstructural heterogeneities may leads to the formation of local heated regions known as ``hot spots''. Chemical reaction may trigger at the hot spot regions depending on the hot spot temperature and the duration over which the temperature can be maintained before phenomenon like heat conduction, rarefaction waves withdraws energy from it. There are different mechanisms which can lead to the formation of hot spots including void collapse. The current work is focused towards the sensitivity characterization of two HMX based pressed energetic materials using flyer plate mesoscale simulations. The aim of the current work is to develop mesoscale numerical framework which can perform simulations by replicating the laboratory based flyer plate experiments. The current numerical framework uses an image processing approach to represent the microstructural heterogeneities incorporated in a massively parallel Eulerian code SCIMITAR3D. The chemical decomposition of HMX is modeled using Henson-Smilowitz reaction mechanism. The sensitivity characterization is aimed towards obtaining James initiation threshold curve and comparing it with the experimental results.

Mars Flyer Rocket Propulsion Risk Assessment: ARC Testing

NASA Technical Reports Server (NTRS)

2001-01-01

This report describes the investigation of a 10-N, bipropellant thruster, operating at -40 C, with monomethy1hydrazine (MMH) and 25% nitric oxide in nitrogen tetroxide (MON-25). The thruster testing was conducted as part of a risk reduction activity for the Mars Flyer, a proposed mission to fly a miniature airplane in the Martian atmosphere. Testing was conducted using an existing thruster, designed for MMH and MON-3 propellants. MON-25 oxidizer was successfully manufactured from MON-3 by the addition of nitric oxide. The thruster was operated successfully over a range of propellant temperatures (-40 to 21 C and feed pressures (6.9 to 20.7 kPa). The thruster hardware was always equal or lower than the propellant temperature. Most tests were 30- and 60-second durations, with 600- and 1200-second duration and pulse testing also conducted. When operating at -40 C, the mixture ratio of the thruster shifted from the nominal value of 1.65 to about 1.85, probably caused by an increase in MMH viscosity, with a corresponding reduction in MMH flowrate. Specific impulse at - 40 C (at nominal feed pressures) was 267 sec, while performance was 277 sec at 21 C. This difference in performance was due, in part, to the mixture ratio shift.

Interaction of sleep quality and sleep duration on impaired fasting glucose: a population-based cross-sectional survey in China

PubMed Central

Lou, Peian; Chen, Peipei; Zhang, Lei; Zhang, Pan; Chang, Guiqiu; Zhang, Ning; Li, Ting; Qiao, Cheng

2014-01-01

Objectives To explore the interactions of sleep quality and sleep duration and their effects on impaired fasting glucose (IFG) in Chinese adults. Design Cross-sectional survey. Setting Community-based investigation in Xuzhou, China. Participants 15 145 Chinese men and women aged 18–75 years old who fulfilled the inclusion criteria. Primary and secondary outcome measures The Pittsburgh Sleep Quality Index was used to produce sleep quality categories of good, common and poor. Fasting blood glucose levels were assessed for IFG. Sleep duration was measured by average hours of sleep per night, with categories of <6, 6–8 and >8 h. The products of sleep and family history of diabetes, obesity and age were added to the logistic regression model to evaluate the addictive interaction and relative excess risk of interaction (RERI) on IFG. The attributable proportion (AP) of the interaction and the synergy index (S) were applied to evaluate the additive interaction of two factors. Bootstrap measures were used to calculate 95% CI of RERI, AP and S. Results The prevalence of IFG was greatest in those with poor sleep quality and short sleep duration (OR 6.37, 95% CI 4.66 to 8.67; p<0.001) compared with those who had good sleep quality and 6–8 h sleep duration, after adjusting for confounders. After adjusting for potential confounders RERI, AP and S values (and their 95% CI) were 1.69 (0.31 to 3.76), 0.42 (0.15 to 0.61) and 2.85 (2.14 to 3.92), respectively, for the interaction between poor sleep quality and short sleep duration, and 0.78 (0.12 to 1.43), 0.61 (0.26 to 0.87) and −65 (−0.94 to −0.27) for the interaction between good sleep quality and long sleep duration. Conclusions The results suggest that there are additive interactions between poor sleep quality and short sleep duration. PMID:24625639

High strain rate metalworking with vaporizing foil actuator: Control of flyer velocity by varying input energy and foil thickness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vivek, A., E-mail: vivek.4@osu.edu; Hansen, S. R.; Daehn, Glenn S.

2014-07-15

Electrically driven rapid vaporization of thin metallic foils can generate a high pressure which can be used to launch flyers at high velocities. Recently, vaporizing foil actuators have been applied toward a variety of impulse-based metal working operations. In order to exercise control over this useful tool, it is imperative that an understanding of the effect of characteristics of the foil actuator on its ability for mechanical impulse generation is developed. Here, foil actuators made out of 0.0508 mm, 0.0762 mm, and 0.127 mm thick AA1145 were used for launching AA2024-T3 sheets of thickness 0.508 mm toward a photonic Dopplermore » velocimeter probe. Launch velocities ranging between 300 m/s and 1100 m/s were observed. In situ measurement of velocity, current, and voltage assisted in understanding the effect of burst current density and deposited electrical energy on average pressure and velocity with foil actuators of various thicknesses. For the pulse generator, geometry, and flyer used here, the 0.0762 mm thick foil was found to be optimal for launching flyers to high velocities over short distances. Experimenting with annealed foil actuators resulted in no change in the temporal evolution of flyer velocity as compared to foil actuators of full hard temper. A physics-based analytical model was developed and found to have reasonable agreement with experiment.« less

Short sleep duration and dietary intake: epidemiological evidence, mechanisms, and health implications

USDA-ARS?s Scientific Manuscript database

Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mechanistically mediated through changes in dietary intake. This review aims to provide an overview of recent epidemiologic studies on the relationships between habitual short sleep durat...

Insomnia with objective short sleep duration is associated with longer duration of insomnia in the Freiburg Insomnia Cohort compared to insomnia with normal sleep duration, but not with hypertension

PubMed Central

Johann, Anna F.; Hertenstein, Elisabeth; Kyle, Simon D.; Baglioni, Chiara; Feige, Bernd; Nissen, Christoph; McGinness, Alastair J.; Riemann, Dieter; Spiegelhalder, Kai

2017-01-01

Study objectives To replicate the association between insomnia with objective short sleep duration and hypertension, type 2 diabetes and duration of insomnia. Design Retrospective case-control study. Setting Department of Psychiatry and Psychotherapy, Medical Center—University of Freiburg. Participants 328 patients with primary insomnia classified according to DSM-IV criteria (125 males, 203 females, 44.3 ± 12.2 years). Interventions N/A Measurements All participants were investigated using polysomnography, blood pressure measurements, and fasting routine laboratory. Results Insomnia patients with short sleep duration (< 6 hours) in the first night of laboratory sleep presented with a longer duration of insomnia compared to those with normal sleep duration (≥ 6 hours) in the first night of laboratory sleep. Insomnia patients who were categorised as short sleepers in either night were not more likely to suffer from hypertension (systolic blood pressure of ≥ 140 mm Hg, diastolic blood pressure of ≥ 90 mm Hg, or a previously established diagnosis). Data analysis showed that insomnia patients with objective short sleep duration were not more likely to suffer from type 2 diabetes (fasting plasma glucose level of ≥ 126 mg/dl, or a previously established diagnosis). However, the diabetes analysis was only based on a very small number of diabetes cases. As a new finding, insomnia patients who were categorised as short sleepers in either night presented with increases in liver enzyme levels. Conclusions The finding on insomnia duration supports the concept of two distinct sub-groups of insomnia, namely insomnia with, and without, objectively determined short sleep duration. However, our data challenges previous findings that insomnia patients with short sleep duration are more likely to suffer from hypertension. PMID:28746413

Insomnia with objective short sleep duration is associated with longer duration of insomnia in the Freiburg Insomnia Cohort compared to insomnia with normal sleep duration, but not with hypertension.

PubMed

Johann, Anna F; Hertenstein, Elisabeth; Kyle, Simon D; Baglioni, Chiara; Feige, Bernd; Nissen, Christoph; McGinness, Alastair J; Riemann, Dieter; Spiegelhalder, Kai

2017-01-01

To replicate the association between insomnia with objective short sleep duration and hypertension, type 2 diabetes and duration of insomnia. Retrospective case-control study. Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg. 328 patients with primary insomnia classified according to DSM-IV criteria (125 males, 203 females, 44.3 ± 12.2 years). N/A. All participants were investigated using polysomnography, blood pressure measurements, and fasting routine laboratory. Insomnia patients with short sleep duration (< 6 hours) in the first night of laboratory sleep presented with a longer duration of insomnia compared to those with normal sleep duration (≥ 6 hours) in the first night of laboratory sleep. Insomnia patients who were categorised as short sleepers in either night were not more likely to suffer from hypertension (systolic blood pressure of ≥ 140 mm Hg, diastolic blood pressure of ≥ 90 mm Hg, or a previously established diagnosis). Data analysis showed that insomnia patients with objective short sleep duration were not more likely to suffer from type 2 diabetes (fasting plasma glucose level of ≥ 126 mg/dl, or a previously established diagnosis). However, the diabetes analysis was only based on a very small number of diabetes cases. As a new finding, insomnia patients who were categorised as short sleepers in either night presented with increases in liver enzyme levels. The finding on insomnia duration supports the concept of two distinct sub-groups of insomnia, namely insomnia with, and without, objectively determined short sleep duration. However, our data challenges previous findings that insomnia patients with short sleep duration are more likely to suffer from hypertension.

Short sleep duration and dietary intake: epidemiologic evidence, mechanisms, and health implications

USDA-ARS?s Scientific Manuscript database

Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mediated through changes in dietary intake. This review provides an overview of recent epidemiologic studies on the relations between habitual short sleep duration and dietary intake in a...

Short and long sleep duration associated with race/ethnicity, sociodemographics, and socioeconomic position.

PubMed

Whinnery, Julia; Jackson, Nicholas; Rattanaumpawan, Pinyo; Grandner, Michael A

2014-03-01

Short and/or long sleep duration are associated with cardiometabolic disease risk and may be differentially experienced among minorities and the socioeconomically disadvantaged. The present study examined nationally representative data along multiple dimensions of race/ ethnicity and socioeconomic status. Cross-sectional. Survey. 2007-2008 NHANES (N = 4,850). None. Self-reported sleep duration was classified as very short (< 5 h), short (5-6 h), normative (7-8 h) and long (≥ 9 h). Population-weighted multinomial logistic regression analyses examined race/ ethnicity, country of origin, language, income, education, health insurance, and food security, controlling for all others as well as age, sex, marital-status, and overall self-rated health. Outcome was self-reported sleep duration, relative to normative sleep duration. Blacks/African Americans were more likely than whites to report very short (OR = 2.34, P < 0.001) and short (OR = 1.85, P < 0.001) sleep. Mexican Americans reported less long sleep (OR = 0.36, P = 0.032). Other Hispanics/ Latinos reported more very short sleep (OR = 2.69, P = 0.025). Asians/ Others reported more very short (OR = 3.99, P = 0.002) and short (OR = 2.08, P = 0.002) sleep. Mexico-born adults reported less short sleep (OR = 0.63, P = 0.042). Spanish-only speakers reported less very short sleep (OR = 0.32, P = 0.030). Lower income groups reported more very short sleep versus > $75,000. Compared to college graduates, increased very short sleep was seen among all lower education levels. Those with public insurance reported more very short (OR = 1.67, P = 0.31) and long (OR = 1.83, P = 0.011) sleep versus uninsured. Very low food security was associated with very short (OR = 1.86, P = 0.036) and short (OR = 1.44, P = 0.047) sleep. Minority status and lower socioeconomic position were associated with shorter self-reported sleep durations.

Material strength measured by flyer-impact perturbation method

NASA Astrophysics Data System (ADS)

Ma, Xiaojuan; Asimow, Paul; Fatyanov, Oleg; Liu, Fusheng

2017-06-01

Yield strength is one of the most important physical properties of a solid material, especially far from its melting line. The flyer-impact perturbation method measures material yield strength on the basis of correlation between the yield strength under shock compression and the damping of oscillatory perturbations in the shape of a shock front passing through the material. We used flyer-plate impacts experiments on targets with machined grooves on the impact surface to shock aluminum to between 32 and 71 GPa and recorded the evolution of the shock front perturbation amplitude in the sample with electric pins and fibers. Simulations using the elastic-plastic model can be matched to the experiments, explaining well the form of the perturbation decay and constraining the yield strength of aluminum to be 1.3-3.1 GPa. These results are in agreement with values obtained from reshock and release wave profiles as well as the result deduced from the SCG model. We conclude that the flyer-impact perturbation method is indeed a reliable means to measure material strength. This work was supported by the National Natural Science Foundation of China (Grant No. 41674088) and the State Scholarship Fund of China Scholarship Council.

Persistent Insomnia: the Role of Objective Short Sleep Duration and Mental Health

PubMed Central

Vgontzas, Alexandros N.; Fernandez-Mendoza, Julio; Bixler, Edward O.; Singareddy, Ravi; Shaffer, Michele L.; Calhoun, Susan L.; Liao, Duanping; Basta, Maria; Chrousos, George P.

2012-01-01

Study Objectives: Few population-based, longitudinal studies have examined risk factors for persistent insomnia, and the results are inconsistent. Furthermore, none of these studies have examined the role of polysomnographic (PSG) variables such as sleep duration or sleep apnea on the persistence of insomnia. Design: Representative longitudinal study. Setting: Sleep laboratory. Participants: From a random, general population sample of 1741 individuals of the adult Penn State Cohort, 1395 were followed-up after 7.5 years. Measurements: Individuals underwent one-night PSG and full medical evaluation at baseline and a telephone interview at follow-up. PSG sleep duration was analyzed as a continuous variable and as a categorical variable: < 6 h sleep (short sleep duration) and ≥ 6 h sleep (longer sleep duration). Results: The rates of insomnia persistence, partial remission, and full remission were 44.0%, 30.0%, and 26.0%, respectively. Objective short sleep duration significantly increased the odds of persistent insomnia as compared to normal sleep (OR = 3.19) and to fully remitted insomnia (OR = 4.92). Mental health problems at baseline were strongly associated with persistent insomnia as compared to normal sleep (OR = 9.67) and to a lesser degree compared to fully remitted insomnia (OR = 3.68). Smoking, caffeine, and alcohol consumption and sleep apnea did not predict persistent insomnia. Conclusions: Objective short sleep duration and mental health problems are the strongest predictors of persistent insomnia. These data further support the validity and clinical utility of objective short sleep duration as a novel marker of the biological severity of insomnia. Citation: Vgontzas AN; Fernandez-Mendoza J; Bixler EO; Singareddy R; Shaffer ML; Calhoun SL; Liao D; Basta M; Chrousos GP. Persistent insomnia: the role of objective short sleep duration and mental health. SLEEP 2012;35(1):61-68. PMID:22215919

Short and Long Sleep Duration Associated with Race/Ethnicity, Sociodemographics, and Socioeconomic Position

PubMed Central

Whinnery, Julia; Jackson, Nicholas; Rattanaumpawan, Pinyo; Grandner, Michael A.

2014-01-01

Study Objectives: Short and/or long sleep duration are associated with cardiometabolic disease risk and may be differentially experienced among minorities and the socioeconomically disadvantaged. The present study examined nationally representative data along multiple dimensions of race/ ethnicity and socioeconomic status. Design: Cross-sectional. Setting: Survey. Patients or Participants: 2007-2008 NHANES (N = 4,850). Interventions: None. Measurements and Results: Self-reported sleep duration was classified as very short (< 5 h), short (5-6 h), normative (7-8 h) and long (≥ 9 h). Population-weighted multinomial logistic regression analyses examined race/ ethnicity, country of origin, language, income, education, health insurance, and food security, controlling for all others as well as age, sex, marital-status, and overall self-rated health. Outcome was self-reported sleep duration, relative to normative sleep duration. Blacks/African Americans were more likely than whites to report very short (OR = 2.34, P < 0.001) and short (OR = 1.85, P < 0.001) sleep. Mexican Americans reported less long sleep (OR = 0.36, P = 0.032). Other Hispanics/ Latinos reported more very short sleep (OR = 2.69, P = 0.025). Asians/ Others reported more very short (OR = 3.99, P = 0.002) and short (OR = 2.08, P = 0.002) sleep. Mexico-born adults reported less short sleep (OR = 0.63, P = 0.042). Spanish-only speakers reported less very short sleep (OR = 0.32, P = 0.030). Lower income groups reported more very short sleep versus > $75,000. Compared to college graduates, increased very short sleep was seen among all lower education levels. Those with public insurance reported more very short (OR = 1.67, P = 0.31) and long (OR = 1.83, P = 0.011) sleep versus uninsured. Very low food security was associated with very short (OR = 1.86, P = 0.036) and short (OR = 1.44, P = 0.047) sleep. Conclusions: Minority status and lower socioeconomic position were associated with shorter self-reported sleep

Short Sleep Duration is an Independent Predictor of Cardiovascular Events in Japanese Hypertensive Patients

PubMed Central

Eguchi, Kazuo; Pickering, Thomas G.; Schwartz, Joseph E.; Hoshide, Satoshi; Ishikawa, Joji; Ishikawa, Shizukiyo; Shimada, Kazuyuki; Kario, Kazuomi

2013-01-01

Context It is not known whether short duration of sleep is a predictor of future cardiovascular events in hypertensive patients. Objective To test the hypothesis that short duration of sleep is independently associated with incident cardiovascular diseases (CVD). Design, Setting, and Participants We performed ambulatory BP monitoring (ABPM) in 1255 subjects with hypertension (mean age: 70.4±9.9 years) and they were followed for an average of 50±23 months. Short sleep duration was defined as <7.5 hrs (20th percentile). Multivariable Cox hazard models predicting CVD events were used to estimate the adjusted hazard ratio (HR) and 95% CI for short sleep duration. A riser pattern was defined when average nighttime SBP exceeded daytime SBP. Main Outcome Measures The end point was cardiovascular events: stroke, fatal or non-fatal myocardial infarction (MI), and sudden cardiac death. Results In multivariable analyses, short duration of sleep (<7.5 hrs) was associated with incident CVD (HR=1.68; 1.06–2.66, P=.03). A synergistic interaction was observed between short sleep duration and the riser pattern (P=.089). When subjects were categorized on the basis of their sleep time and riser/non-riser patterns, the shorter sleep+riser group had a substantially and significantly higher incidence of CVD than the predominant normal sleep+non-riser group (HR=4.43;2.09–9.39, P<0.001), independent of covariates. Conclusions Short duration of sleep is associated with incident CVD risk, and the combination of riser pattern and short duration of sleep that is most strongly predictive of future CVD, independent of ambulatory BP levels. Physicians should inquire about sleep duration in the risk assessment of hypertensive patients. PMID:19001199

Laser-driven short-duration heating angioplasty: dilatation performance in cadaver atherosclerotic femoral arteries

NASA Astrophysics Data System (ADS)

Shimazaki, Natsumi; Naruse, Sho; Arai, Tsunenori; Imanishi, Nobuaki; Aiso, Sadakazu

2013-03-01

The purpose of this study was to investigate the artery dilatation performance of the short-duration heating balloon catheter in cadaver stenotic arteries. We designed a prototype short-duration heating balloon catheter that can heat artery media to around 60 °C in 15-25 s by a combination of laser-driven heat generation and continuous fluid irrigation in the balloon. We performed ex vivo short-duration heating dilatation in the cadaver atherosclerotic femoral arteries (initial percent diameter stenosis was 36-98%), with the maximum balloon temperature of 65+/-5 °C, laser irradiation duration of 25 s, and balloon dilatation pressure of 3.5 atm. The artery lumen configurations before and after the dilatations were assessed with a commercial IVUS system. After the short-duration heating dilatations, the percent diameter stenosis was reduced below 30% without any artery tears or dissections. We estimated that the artery media temperature was raised to around 60 °C in which plaque thickness was below 0.8 mm by a thermal conduction calculation. The estimated maximum temperature in artery adventitia and surrounding tissue was up to 45 °C. We found that the short-duration heating balloon could sufficiently dilate the cadaver stenotic arteries, without thermal injury in artery adventitia and surroundings.

Persistent insomnia: the role of objective short sleep duration and mental health.

PubMed

Vgontzas, Alexandros N; Fernandez-Mendoza, Julio; Bixler, Edward O; Singareddy, Ravi; Shaffer, Michele L; Calhoun, Susan L; Liao, Duanping; Basta, Maria; Chrousos, George P

2012-01-01

Few population-based, longitudinal studies have examined risk factors for persistent insomnia, and the results are inconsistent. Furthermore, none of these studies have examined the role of polysomnographic (PSG) variables such as sleep duration or sleep apnea on the persistence of insomnia. Representative longitudinal study. Sleep laboratory. From a random, general population sample of 1741 individuals of the adult Penn State Cohort, 1395 were followed-up after 7.5 years. Individuals underwent one-night PSG and full medical evaluation at baseline and a telephone interview at follow-up. PSG sleep duration was analyzed as a continuous variable and as a categorical variable: < 6 h sleep (short sleep duration) and ≥ 6 h sleep (longer sleep duration). The rates of insomnia persistence, partial remission, and full remission were 44.0%, 30.0%, and 26.0%, respectively. Objective short sleep duration significantly increased the odds of persistent insomnia as compared to normal sleep (OR = 3.19) and to fully remitted insomnia (OR = 4.92). Mental health problems at baseline were strongly associated with persistent insomnia as compared to normal sleep (OR = 9.67) and to a lesser degree compared to fully remitted insomnia (OR = 3.68). Smoking, caffeine, and alcohol consumption and sleep apnea did not predict persistent insomnia. Objective short sleep duration and mental health problems are the strongest predictors of persistent insomnia. These data further support the validity and clinical utility of objective short sleep duration as a novel marker of the biological severity of insomnia.

Associations of a Short Sleep Duration, Insufficient Sleep, and Insomnia with Self-Rated Health among Nurses.

PubMed

Silva-Costa, Aline; Griep, Rosane Härter; Rotenberg, Lúcia

2015-01-01

Epidemiological evidence suggests that sleep duration and poor sleep are associated with mortality, as well as with a wide range of negative health outcomes. However, few studies have examined the association between sleep and self-rated health, particularly through the combination of sleep complaints. The objective of this study was to examine whether self-rated health is associated with sleep complaints, considering the combination of sleep duration, insomnia, and sleep sufficiency. This cross-sectional study was performed in the 18 largest public hospitals in the city of Rio de Janeiro, Brazil. A total of 2518 female nurses answered a self-filled multidimensional questionnaire. The adjusted odds ratios and 95% confidence intervals (CIs) estimated the chance of poor self-rated health in the presence of different combinations of sleep duration and quality. Compared with women who reported adequate sleep duration with no sleep quality complaints (reference group), the odds ratios (95% CI) for poor self-rated health were 1.79 (1.27-2.24) for those who reported only insufficient sleep, 1.85 (0.94-3.66) for only a short sleep duration, and 3.12 (1.94-5.01) for only insomnia. Compared with those who expressed all three complaints (short sleep duration, insomnia, and insufficient sleep), the odds ratio for poor self-rated health was 4.49 (3.25-6.22). Differences in the magnitude of the associations were observed, depending on the combination of sleep complaints. Because self-rated health is a consistent predictor of morbidity, these results reinforce the increasing awareness of the role of sleep in health and disease. Our findings contribute to the recognition of sleep as a public health matter that deserves to be better understood and addressed by policymakers.

Short sleep duration as an independent predictor of cardiovascular events in Japanese patients with hypertension.

PubMed

Eguchi, Kazuo; Pickering, Thomas G; Schwartz, Joseph E; Hoshide, Satoshi; Ishikawa, Joji; Ishikawa, Shizukiyo; Shimada, Kazuyuki; Kario, Kazuomi

2008-11-10

It is not known whether short duration of sleep is a predictor of future cardiovascular events in patients with hypertension. To test the hypothesis that short duration of sleep is independently associated with incident cardiovascular diseases (CVD), we performed ambulatory blood pressure (BP) monitoring in 1255 subjects with hypertension (mean [SD] age, 70.4 [9.9] years) and followed them for a mean period of 50 (23) months. Short sleep duration was defined as less than 7.5 hours (20th percentile). Multivariable Cox hazard models predicting CVD events were used to estimate the adjusted hazard ratio and 95% confidence interval (CI) for short sleep duration. A riser pattern was defined when mean nighttime systolic BP exceeded daytime systolic BP. The end point was a cardiovascular event: stroke, fatal or nonfatal myocardial infarction (MI), and sudden cardiac death. In multivariable analyses, short duration of sleep (<7.5 hours) was associated with incident CVD (hazard ratio [HR], 1.68; 95% CI, 1.06-2.66; P = .03). A synergistic interaction was observed between short sleep duration and the riser pattern (P = .09). When subjects were classified according to their sleep time and a riser vs nonriser pattern, the group with shorter sleep duration plus the riser pattern had a substantially and significantly higher incidence of CVD than the group with predominant normal sleep duration plus the nonriser pattern (HR, 4.43; 95% CI, 2.09-9.39; P < .001), independent of covariates. Short duration of sleep is associated with incident CVD risk and the combination of the riser pattern and short duration of sleep that is most strongly predictive of future CVD, independent of ambulatory BP levels. Physicians should inquire about sleep duration in the risk assessment of patients with hypertension.

Experimental short-duration techniques. [gas turbine engine tests

NASA Technical Reports Server (NTRS)

Dunn, Michael G.

1986-01-01

Short-duration facilities used for gas turbine studies are described. Data recording techniques; and instruments (thin-film heat flux gages, high-frequency response pressure measurements, total temperature probes, measurement of rotor tip speed, active measurement of tip clearance) are presented.

The international space station as a free flyer servicing node

NASA Astrophysics Data System (ADS)

Antol, Jeffrey; Headley, David E.

1999-01-01

The International Space Station will provide a multitude of opportunities for an expanding customer base to make use of this international resource. One such opportunity is servicing of various visiting vehicles that are in a similar orbit to the station. Servicing may include change-out of payloads, replenishment of consumables, repair, and refurbishment operations. Previous studies have been conducted in which ``paper'' free flyers have been assessed against the station's ability to accommodate them. Over the last several months though, an already flown free flyer, EURECA, was assessed as a real-life visiting free flyer design reference mission. Issues such as capture/berthing, servicing, logistics support, and stowage were assessed for station design and operational approaches. This paper will highlight critical visiting vehicle design considerations, identify station issues, and provide recommendations for accommodation of a wide range of visiting vehicle requirements of the future.

The International Space Station As a Free Flyer Servicing Node

NASA Technical Reports Server (NTRS)

Antol, Jeffrey; Headley, David E.

1999-01-01

The International Space Station will provide a multitude of opportunities for an expanding customer base to make use of this international resource. One such opportunity is servicing of various visiting vehicles that are in a similar orbit to the station. Servicing may include change-out of payloads, replenishment of consumables, repair, and refurbishment operations. Previous studies have been conducted in which "paper" free flyers have been assessed against the station s ability to accommodate them. Over the last several months though, an already flown free flyer, EURECA, was assessed as a real-life visiting free flyer design reference mission. Issues such as capture/berthing, servicing, logistics support, and stowage were assessed for station design and operational approaches. This paper will highlight critical visiting vehicle design considerations, identify station issues, and provide recommendations for accommodation of a wide range of visiting vehicle requirements of the future.

Earth orientation determinations by short duration VLBI observations

NASA Astrophysics Data System (ADS)

Nothnagel, Axel; Zhihan, Qian; Nicolson, George D.; Tomasi, Paolo

1994-03-01

In May 1989 and April 1990 the radio telescopes of the Wettzell Geodetic Fundamental Station in Germany and of the Shanghai Observatory near Seshan in China observed two series of daily VLBI experiments of short duration for precise determination of UT1. In 1990 a few experiments were complemented by the Hartebeesthoek Radio Astronomy Observatory in South Africa and the Medicina telescope of the Bologna Istituto di Radioastronomia in Italy. Employing the South African station together with the east-west baseline formed by the observatories of Seshan and Medicina permitted simultaneous determinations of UT1 and polar motion. Here we report on the results of these observations. Comparing the UT1 results with those of the IRIS Intensive series gives a clear indication of the absolute accuracy of such short duration VLBI measurements which is estimated to be of the order of ±60 µs.

Duration and quality of the peer review process: the author's perspective.

PubMed

Huisman, Janine; Smits, Jeroen

2017-01-01

To gain insight into the duration and quality of the scientific peer review process, we analyzed data from 3500 review experiences submitted by authors to the SciRev.sc website. Aspects studied are duration of the first review round, total review duration, immediate rejection time, the number, quality, and difficulty of referee reports, the time it takes authors to revise and resubmit their manuscript, and overall quality of the experience. We find clear differences in these aspects between scientific fields, with Medicine, Public health, and Natural sciences showing the shortest durations and Mathematics and Computer sciences, Social sciences, Economics and Business, and Humanities the longest. One-third of journals take more than 2 weeks for an immediate (desk) rejection and one sixth even more than 4 weeks. This suggests that besides the time reviewers take, inefficient editorial processes also play an important role. As might be expected, shorter peer review processes and those of accepted papers are rated more positively by authors. More surprising is that peer review processes in the fields linked to long processes are rated highest and those in the fields linked to short processes lowest. Hence authors' satisfaction is apparently influenced by their expectations regarding what is common in their field. Qualitative information provided by the authors indicates that editors can enhance author satisfaction by taking an independent position vis-à-vis reviewers and by communicating well with authors.

The pitch of short-duration fundamental frequency glissandos.

PubMed

d'Alessandro, C; Rosset, S; Rossi, J P

1998-10-01

Pitch perception for short-duration fundamental frequency (F0) glissandos was studied. In the first part, new measurements using the method of adjustment are reported. Stimuli were F0 glissandos centered at 220 Hz. The parameters under study were: F0 glissando extents (0, 0.8, 1.5, 3, 6, and 12 semitones, i.e., 0, 10.17, 18.74, 38.17, 76.63, and 155.56 Hz), F0 glissando durations (50, 100, 200, and 300 ms), F0 glissando directions (rising or falling), and the extremity of F0 glissandos matched (beginning or end). In the second part, the main results are discussed: (1) perception seems to correspond to an average of the frequencies present in the vicinity of the extremity matched; (2) the higher extremities of the glissando seem more important; (3) adjustments at the end are closer to the extremities than adjustments at the beginning. In the third part, numerical models accounting for the experimental data are proposed: a time-average model and a weighted time-average model. Optimal parameters for these models are derived. The weighted time-average model achieves a 94% accurate prediction rate for the experimental data. The numerical model is successful in predicting the pitch of short-duration F0 glissandos.

INSOMNIA WITH OBJECTIVE SHORT SLEEP DURATION AND INCIDENT HYPERTENSION: THE PENN STATE COHORT

PubMed Central

Fernandez-Mendoza, Julio; Vgontzas, Alexandros N.; Liao, Duanping; Shaffer, Michele L.; Vela-Bueno, Antonio; Basta, Maria; Bixler, Edward O.

2013-01-01

Insomnia with objective short sleep duration appears to be a biologically more severe phenotype of the disorder. No longitudinal study to date has examined the association of this type of insomnia with incident hypertension using polysomnography. From a random, general population sample of 1741 adults of the Penn State Cohort, 1395 were followed-up after 7.5 years and 786 did not have hypertension at baseline. Hypertension was determined by a self-report of receiving treatment for high blood pressure. Chronic insomnia was defined as a complaint of insomnia lasting ≥ 1 year, while poor sleep was defined as moderate-to-severe sleep difficulties. All subjects underwent 8-hour polysomnography. Sleep disordered breathing (SDB) was defined as an obstructive apnea/hypopnea index ≥ 5. We used the median polysomnographic percent of sleep time to define short sleep duration (i.e., < 6 hours). We controlled for gender, race, age, caffeine, cigarettes, alcohol consumption, depression, SDB, diabetes, obesity, and blood pressure in our analyses. Compared to normal sleepers who slept ≥ 6 hours, the highest risk for incident hypertension was in chronic insomniacs with short sleep duration (OR= 3.8, 95% CI=1.6–9.0). The risk for incident hypertension in poor sleepers with short sleep duration was significantly increased but became marginally significant after controlling for obesity (OR= 1.6, 95% CI=0.9–2.8). Chronic insomnia with short sleep duration is associated with an increased risk for incident hypertension in a degree comparable to SDB. Objective short sleep duration in insomnia may serve as a useful predictor of the biological severity of the disorder. PMID:22892811

Force Measurements in Short-Duration Hypersonic Facilities

DTIC Science & Technology

1975-11-01

method which depends upon a double differentiation of experimental data, albeit smoothed. When the motion is non -plarnar, the tricyclic method of...J.0. & Hamaker, F.M. An experimental investigation of the base pressure characteristics of (1955) non -lifting bodies of revolution at Mach numbers...AD-AO18 842 FORCE MEASUREMENTS IN SHORT-DURATION HYPERSONIC FACILITIES Leonard Bernstein, et al Advisory Group for Aerospace Research and Development

Effects of Short- and Long-Duration Space Flight on Neuromuscular Function

NASA Technical Reports Server (NTRS)

Buxton, Roxanne E.; Spiering, Barry A.; Ryder, Jeffrey W.; Ploutz-Snyder, Lori L.; Bloomberg, Jacob J.

2010-01-01

The Functional Task Tests (FTT) is an interdisciplinary study designed to correlate the changes in functional tasks (such as emergency egress, ladder climbing, and hatch opening) with changes in neuromuscular, cardiovascular, and sensorimotor function. One aspect of the FTT, the neuromuscular function test, is used to investigate the neuromuscular component underlying changes in the ability of astronauts to perform functional tasks (representative of critical mission tasks) safely and quickly after flight. PURPOSE: To describe neuromuscular function after short- and long-duration space flight. METHODS: To date, 5 crewmembers on short-duration (10- to 15-day) missions and 3 on long-duration missions have participated. Crewmembers were assessed 30 days before flight, on landing day (short-duration subjects only) and 1, 6, and 30 days after landing. The interpolated twitch technique, which utilizes a combination of maximal voluntary contractions and electrically evoked contractions, was used to assess the maximal voluntary isometric force (MIF) and central activation capacity of the knee extensors. Leg-press and bench-press devices were used to assess MIF and maximal dynamic power of the lower and upper body respectively. Specifically, power was measured during concentric-only ballistic throws of the leg-press sled and bench-press bar loaded to 40% and 30% of MIF respectively. RESULTS: Data are currently being collected from both Shuttle and ISS crewmembers. Emerging data indicate that measures of knee extensor muscle function are decreased with long-duration flight. DISCUSSION: The relationships between flight duration, neural drive, and muscle performance are of particular interest. Ongoing research will add to the current sample size and will focus on defining changes in muscle performance measures after long-duration space flight.

The association of sleep duration and sleep quality with non-alcoholic fatty liver disease in a Taiwanese population.

PubMed

Chou, Yu-Tsung; Cheng, Hsiang-Ju; Wu, Jin-Shang; Yang, Yi-Ching; Chou, Chieh-Ying; Chang, Chih-Jen; Lu, Feng-Hwa

2018-06-18

The association of sleep duration/quality with nonalcoholic fatty liver disease (NAFLD) is inconclusive. Several important covariates were not adjusted concomitantly in some studies, and the severity of NAFLD was not considered. Furthermore, the gender impact of sleep duration or sleep quality on NAFLD remains unclear. We thus aimed to examine the association of sleep duration and quality with NAFLD by gender in a Taiwanese population. A total of 6663 subjects aged 18 years or more were enrolled. The severity of NAFLD was divided into mild, moderate, and severe degrees based on ultrasound findings. The sleep duration was classified into three groups: short (<6h), normal (6-8h), and long (>8h). Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality, and poor sleep quality was defined as a global PSQI score greater than 5. After adjustment for potential confounders, multinomial logistic regression showed that poor sleep quality was negatively associated with both mild and moderate-to-severe NAFLD in males, but sleep duration was not independently related to NAFLD. In females, sleep condition was not related to NAFLD. Poor sleep quality but not sleep duration was associated with a lower risk of not only moderate to severe but also mild NAFLD in males. In females, the association of sleep quality and duration with the risk of NAFLD was insignificant. Copyright © 2018 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

The Wire Flyer Towed Profiling System

NASA Astrophysics Data System (ADS)

Roman, C.; Ullman, D. S.; Hebert, D.

2016-02-01

The Wire Flyer is an autonomous profiling vehicle that slides up and down a standard towed cable in a controlled manner using the lift created by wing foils. The vehicle is able to create high resolution water-column sections within a specified depth band in an automated manner. The Wire Flyer is different than standard undulating tow bodies in that it decouples the vehicle's motion from the tow cable dynamics. Due to this separation the vehicle is able to profile with nearly 1:1 horizontal to vertical motion. A heavy depressor weight is fixed to the end of the cable and the cable shape remains relatively static during operation. The vehicle uses a closed loop wing angle controller to achieve desired vertical velocities between 0 and 2.5 m/s for ship speeds between 1.5 and 2.5 m/s. During typical operations, updated commands and condensed data samples can be sent to and from the vehicle via an acoustic modem to adjust the profiling pattern to ensure the desired coverage. The current 1000 meter rated vehicle is equipped with a SBE 49 FastCAT CTD, and can carry additional sensors for oxygen, Chlorophyll fluorescence and acoustic echosounding. Results showing the vehicle performance as well as the quality of the processed CTD data will be presented from three test cruises to the New England Shelf Break Front. Many shallow and deep sections were obtained with horizontal resolution that is not otherwise achievable with undulating tow bodies, underway CTDs, standard CTD tow-yos, gliders or free swimming AUVs. A typical survey at ship speeds of 3-4 knots can profile over a depth band between 200 and 600 meters depth with a repeat cycle length of less than 1 km. The vehicle concept is depth independent and could work with a full ocean depth design. Application areas for the system include sub-meso scale observations of fronts, vent and seep plumes, oxygen minimum layers, mixing and mid-water bioacoustics.

Speaker-Sex Discrimination for Voiced and Whispered Vowels at Short Durations.

PubMed

Smith, David R R

2016-01-01

Whispered vowels, produced with no vocal fold vibration, lack the periodic temporal fine structure which in voiced vowels underlies the perceptual attribute of pitch (a salient auditory cue to speaker sex). Voiced vowels possess no temporal fine structure at very short durations (below two glottal cycles). The prediction was that speaker-sex discrimination performance for whispered and voiced vowels would be similar for very short durations but, as stimulus duration increases, voiced vowel performance would improve relative to whispered vowel performance as pitch information becomes available. This pattern of results was shown for women's but not for men's voices. A whispered vowel needs to have a duration three times longer than a voiced vowel before listeners can reliably tell whether it's spoken by a man or woman (∼30 ms vs. ∼10 ms). Listeners were half as sensitive to information about speaker-sex when it is carried by whispered compared with voiced vowels.

Speaker-Sex Discrimination for Voiced and Whispered Vowels at Short Durations

PubMed Central

2016-01-01

Whispered vowels, produced with no vocal fold vibration, lack the periodic temporal fine structure which in voiced vowels underlies the perceptual attribute of pitch (a salient auditory cue to speaker sex). Voiced vowels possess no temporal fine structure at very short durations (below two glottal cycles). The prediction was that speaker-sex discrimination performance for whispered and voiced vowels would be similar for very short durations but, as stimulus duration increases, voiced vowel performance would improve relative to whispered vowel performance as pitch information becomes available. This pattern of results was shown for women’s but not for men’s voices. A whispered vowel needs to have a duration three times longer than a voiced vowel before listeners can reliably tell whether it’s spoken by a man or woman (∼30 ms vs. ∼10 ms). Listeners were half as sensitive to information about speaker-sex when it is carried by whispered compared with voiced vowels. PMID:27757218

A Nuclear Ramjet Flyer for Exploration of Jovian Atmosphere

NASA Astrophysics Data System (ADS)

Maise, G.; Powell, J.; Paniagua, J.; Lecat, R.

2001-01-01

We investigated the design, operation, and data gathering possibilities of a nuclear-powered ramjet flyer in the Jovian atmosphere. The MITEE nuclear rocket engine can be modified to operate as a ramjet in planetary atmospheres. (Note: MITEE is a compact, ultra-light-weight thermal nuclear rocket which uses hydrogen as the propellant.) To operate as a ramjet, MITEE requires a suitable inlet and diffuser to substitute for the propellant that is pumped from the supply tanks in a nuclear rocket engine. Such a ramjet would fly in the upper Jovian atmosphere, mapping in detail temperatures, pressures, compositions, lightning activity, and wind speeds in the highly turbulent equatorial zone and the Great Red Spot. The nuclear ramjet could operate for months because: (1) the Jovian atmosphere has unlimited propellant, (2) the MITEE nuclear reactor is a (nearly) unlimited power source, and (3) with few moving parts, mechanical wear should be minimal. This paper presents a conceptual design of a ramjet flyer and its nuclear engine. The flyer incorporates a swept-wing design with instruments located in the twin wing-tip pods (away from the radiation source and readily shielded, if necessary). The vehicle is 2 m long with a 2 m wingspan. Its mass is 220 kg, and its nominal flight Mach number is 1.5. Based on combined neutronic and thermal/hydraulic analyses, we calculated that the ambient pressure range over which the flyer can operate to be from about 0.04 to 4 (terrestrial) atmospheres. This altitude range encompasses the three uppermost cloud layers in the Jovian atmosphere: (1) the entire uppermost visible NH3 ice cloud layer (where lightning has been observed), (2) the entire NH4HS ice cloud layer, and (3) the upper portion of the H2O ice cloud layer.

Effect of daily short-duration weight-bearing on disuse-induced deterioration of musculoskeletal system

PubMed Central

Leung, K-S.; Li, Y-H.; Liu, Y.; Wang, H.; Tam, K-F.; Chow, D.H.K.; Wan, Y.; Ling, S.; Dai, Z.; Qin, L.; Cheung, W-H.

2015-01-01

Objectives: To investigate deterioration of musculoskeletal system due to prolonged disuse and the potential of daily short-duration weight-bearing as countermeasures. Methods: Twenty-four adult male Sprague-Dawley rats were divided into Control Group (CG, no intervention), Tail-suspension Group (TG, tail-suspension without treatment), and Weight-Bearing Group (WBG, tail-suspension with 20 min/day, 5 days/week body weight loading). After four weeks of treatment, femur and tibia, soleus and extensor digitorum longus were evaluated for bone and muscle quality respectively. Tensile properties of bone-tendon insertion (BTI) were evaluated using patella-patellar tendon complex. Results: Disuse induced deterioration on bone, muscle, and BTI after four weeks. Compared with CG, TG and WBG showed significant decrease in bone mineral density (BMD) of trabecular bone in distal femur (4.3-15.2%), muscle mass (31.3-52.3%), muscle cross-sectional area (29.1-35%), and failure strength of BTI (23.9-29.4%). Tensile test showed that the failure mode was avulsion of bone at the BTI. No significant difference was detected between TG and WBG for all assessments on bone, muscle, and BTI. Conclusions: Disuse caused deterioration of bone, muscle, and BTI while daily short-duration of weight-bearing did not prevent this deterioration. Mechanical stimulation with higher intensity and longer duration may be necessary to prevent musculoskeletal deterioration resulted from prolonged disuse. PMID:26032214

Substance use associated with short sleep duration in patients with schizophrenia or schizoaffective disorder.

PubMed

Tang, Vivian K; Pato, Michele T; Sobell, Janet L; Hammond, Terese C; Valdez, Mark M; Lane, Christianne J; Pato, Carlos N

2016-06-01

To examine the association between substance use and short sleep duration in individuals with schizophrenia or schizoaffective disorder, depressive type (SADD). Cross-sectional, retrospective study. Urban, suburban, and rural centers across the United States. 2,462 consented, adult individuals with schizophrenia or schizoaffective disorder, depressive type (SADD). Participants included inpatients in acute or chronic care settings as well as outpatients and residents in community dwellings. Substance use was assessed with 10 questions adopted from well-validated measures (e.g., CAGE questionnaire) for alcohol, marijuana, and illicit drugs. Short sleep duration was defined as <6 hr of self-reported sleep per night. Close to 100% of our sample used nicotine while 83% used substances other than nicotine. More importantly, there was a significant association between substance use and short sleep duration. Interestingly, this association was strongest among African-Americans with schizophrenia or SADD. Because psychiatric medications often target chemical receptors involved with both sleep and substance use, understanding the association between short sleep duration and substance use in individuals with schizophrenia and SADD is important. Given that the majority of premature deaths in individuals with psychotic illness are due to medical conditions associated with modifiable risk factors, prospective studies designed to examine the effect of short sleep duration on behaviors like substance use should be undertaken. Finally, analyzing genetic and environmental data in a future study might help illuminate the strong association found between short sleep duration and substance use in African-Americans with schizophrenia and SADD. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Tilt changes of short duration

USGS Publications Warehouse

McHugh, Stuart

1976-01-01

Section I of this report contains a classification scheme for short period tilt data. For convenience, all fluctuations in the local tilt field of less than 24 hours duration will be designated SP (i.e., short period) tilt events. Three basic categories of waveshape appearance are defined, and the rules for naming the waveforms are outlined. Examples from tilt observations at four central California sites are provided. Section II contains some coseismic tilt data. Fourteen earthquakes in central California, ranging in magnitude from 2.9 to 5.2, were chosen for study on four tiltmeters within 10 source dimensions of the epicenters. The raw records from each of the four tiltmeters at the times of the earthquakes were photographed and are presented in this section. Section III contains documentation of computer programs used in the analysis of the short period tilt data. Program VECTOR computes the difference vector of a tilt event and displays the sequence of events as a head-to-tail vector plot. Program ONSTSP 1) requires two component digitized tilt data as input, 2) scales and plots the data, and 3) computes and displays the amplitude, azimuth, and normalized derivative of the tilt amplitude. Program SHARPS computes the onset sharpness, (i.e., the normalized derivative of the tilt amplitude at the onset of the tilt event) as a function of source-station distance from a model of creep-related tilt changes. Program DSPLAY plots the digitized data.

How wing compliance drives the efficiency of self-propelled flapping flyers.

PubMed

Thiria, Benjamin; Godoy-Diana, Ramiro

2010-07-01

Wing flexibility governs the flying performance of flapping-wing flyers. Here, we use a self-propelled flapping-wing model mounted on a "merry go round" to investigate the effect of wing compliance on the propulsive efficiency of the system. Our measurements show that the elastic nature of the wings can lead not only to a substantial reduction in the consumed power, but also to an increment of the propulsive force. A scaling analysis using a flexible plate model for the wings points out that, for flapping flyers in air, the time-dependent shape of the elastic bending wing is governed by the wing inertia. Based on this prediction, we define the ratio of the inertial forces deforming the wing to the elastic restoring force that limits the deformation as the elastoinertial number N(ei). Our measurements with the self-propelled model confirm that it is the appropriate structural parameter to describe flapping flyers with flexible wings.

Separation dynamics of the COMET FreeFlyer and an upper stage STAR-48V motor

NASA Technical Reports Server (NTRS)

Fuller, Kevin M.; Myers, Carter H.

1993-01-01

In this report, the orbital separation between a STAR-48V upperstage motor and the COMET FreeFlyer is investigated. The time from nominal STAR-48 engine burnout is to be determined such that the STAR-48 will not collide with the FreeFlyer once the separation process has been initiated. To analyze this separation, the forces acting upon both the FreeFlyer and the STAR-48 are described in a body fixed coordinate system. These coordinates are then transformed into an Euler coordinate system and then further transformed into a relative inertial coordinate system. From this analysis and some basic assumptions about the Star-48/FreeFlyer vehicle, it can be concluded that the STAR-48 will not collide with the Free Flyer if the separation occurs at 120 seconds after nominal burnout of the STAR-48. In fact, the separation delay could be a shorter period of time, but it is recommended that this separation delay be as long as possible for risk mitigation. This delay is currently designed to be 120 seconds and the analysis presented in this report shows that this time is acceptable.

Sleep Duration, Sleep Quality, and Markers of Subclinical Arterial Disease in Healthy Men and Women.

PubMed

Kim, Chan-Won; Chang, Yoosoo; Zhao, Di; Cainzos-Achirica, Miguel; Ryu, Seungho; Jung, Hyun-Suk; Yun, Kyung Eun; Choi, Yuni; Ahn, Jiin; Zhang, Yiyi; Rampal, Sanjay; Baek, Youngji; Lima, Joao A; Shin, Hocheol; Guallar, Eliseo; Cho, Juhee; Sung, Eunju

2015-10-01

Short and long sleep duration are associated with increased risk of clinical cardiovascular events, but the association between sleep duration and subclinical cardiovascular disease is not well established. We examined the association between sleep duration and sleep quality with coronary artery calcification (CAC) and with brachial-ankle pulse wave velocity (PWV) in a large sample of young and middle-aged asymptomatic adults. We conducted a cross-sectional study of adult men and women who underwent a health checkup examination, including assessment of sleep duration and quality and coupled with either CAC (n=29 203) or brachial-ankle PWV (n=18 106). The multivariate-adjusted CAC score ratios (95% confidence interval) comparing sleep durations of ≤5, 6, 8, and ≥9 hours with 7 hours of sleep were 1.50 (1.17-1.93), 1.34 (1.10-1.63), 1.37 (0.99-1.89), and 1.72 (0.90-3.28), respectively (P for quadratic trend=0.002). The corresponding average differences in brachial-ankle PWV were 6.7 (0.75-12.6), 2.9 (-1.7 to 7.4), 10.5 (4.5-16.5), and 9.6 (-0.7 to 19.8) cm/s, respectively (P for quadratic trend=0.019). Poor subjective sleep quality was associated with CAC in women but not in men, whereas the association between poor subjective sleep quality and brachial-ankle PWV was stronger in men than in women. In this large study of apparently healthy men and women, extreme sleep duration and poor subjective sleep quality were associated with increased prevalence of CAC and higher PWV. Our results underscore the importance of an adequate quantity and quality of sleep to maintain cardiovascular health. © 2015 American Heart Association, Inc.

Regional muscle loss after short duration spaceflight.

PubMed

LeBlanc, A; Rowe, R; Schneider, V; Evans, H; Hedrick, T

1995-12-01

Muscle strength and limb girth measurements during Skylab and Apollo missions suggested that loss of muscle mass may occur as a result of spaceflight. Extended duration spaceflight is important for the economical and practical use of space. The loss of muscle mass during spaceflight is a medical concern for long duration flights to the planets or extended stays aboard space stations. Understanding the extent and temporal relationships of muscle loss is important for the development of effective spaceflight countermeasures. We hypothesized that significant and measurable changes in muscle volume would occur in Shuttle crewmembers following 8 d of weightlessness. MRI was used to obtain the muscle volumes of the calf, thigh and lower back before and after the STS-47 Shuttle mission. Statistical analyses demonstrated that the soleus-gastrocnemius (-6.3%), anterior calf (-3.9%), hamstrings (-8.3%), quadriceps (-6.0%) and intrinsic back (-10.3%) muscles were decreased, p < 0.05, compared to baseline, 24 h after landing. At 2 weeks post recovery, the hamstrings and intrinsic lower back muscles were still below baseline, p < 0.05. These results demonstrate that even short duration spaceflight can result in significant muscle atrophy.

The effect of detonation wave incidence angle on the acceleration of flyers by explosives heavily laden with inert additives

NASA Astrophysics Data System (ADS)

Loiseau, Jason; Georges, William; Frost, David L.; Higgins, Andrew J.

2017-01-01

The incidence angle of a detonation wave in a conventional high explosive influences the acceleration and terminal velocity of a metal flyer by increasing the magnitude of the material velocity imparted by the transmitted shock wave as the detonation is tilted towards normal loading. For non-ideal explosives heavily loaded with inert additives, the detonation velocity is typically subsonic relative to the flyer sound speed, leading to shockless accelerations when the detonation is grazing. Further, in a grazing detonation the particles are initially accelerated in the direction of the detonation and only gain velocity normal to the initial orientation of the flyer at later times due to aerodynamic drag as the detonation products expand. If the detonation wave in a non-ideal explosive instead strikes the flyer at normal incidence, a shock is transmitted into the flyer and the first interaction between the particle additives and the flyer occurs due to the imparted material velocity from the passage of the detonation wave. Consequently, the effect of incidence angle and additive properties may play a more prominent role in the flyer acceleration. In the present study we experimentally compared normal detonation loadings to grazing loadings using a 3-mm-thick aluminum slapper to impact-initiate a planar detonation wave in non-ideal explosive-particle admixtures, which subsequently accelerated a second 6.4-mm-thick flyer. Flyer acceleration was measured with heterodyne laser velocimetry (PDV). The explosive mixtures considered were packed beds of glass or steel particles of varying sizes saturated with sensitized nitromethane, and gelled nitromethane mixed with glass microballoons. Results showed that the primary parameter controlling changes in flyer velocity was the presence of a transmitted shock, with additive density and particle size playing only secondary roles. These results are similar to the grazing detonation experiments, however under normal loading the

Observations of short-duration gamma-ray bursts

NASA Astrophysics Data System (ADS)

Pozanenko, Alexei; Volnova, Alina; Tungalag, Namkhai; Elenin, Leonid; Molotov, Igor; Voropaev, Victor; Schmalz, Sergey

2014-09-01

Gamma-ray bursts (GRB) are the most powerful cosmological catastrophes in the Universe, with energy releases of 1048 - 1053 erg within a few tens of seconds. It is widely believed that progenitors of the short-duration class of GRB can be merging relativistic binary systems such as a neutron star (NS) and a black hole (BH) or NS-NS. We review the physics of GRBs, their phenomenological properties and observational evidence of GRBs, emphasizing optical observations of GRBs from Mongolia.

Ocular Counter Rolling in Astronauts After Short- and Long-Duration Spaceflight.

PubMed

Reschke, Millard F; Wood, Scott J; Clément, Gilles

2018-05-17

Ocular counter-rolling (OCR) is a reflex generated by the activation of the gravity sensors in the inner ear that stabilizes gaze and posture during head tilt. We compared the OCR measures that were obtained in 6 astronauts before, during, and after a spaceflight lasting 4-6 days with the OCR measures obtained from 6 astronauts before and after a spaceflight lasting 4-9 months. OCR in the short-duration fliers was measured using the afterimage method during head tilt at 15°, 30°, and 45°. OCR in the long-duration fliers was measured using video-oculography during whole body tilt at 25°. A control group of 7 subjects was used to compare OCR measures during head tilt and whole body tilt. No OCR occurred during head tilt in microgravity, and the response returned to normal within 2 hours of return from short-duration spaceflight. However, the amplitude of OCR was reduced for several days after return from long-duration spaceflight. This decrease in amplitude was not accompanied by changes in the asymmetry of OCR between right and left head tilt. These results indicate that the adaptation  of otolith-driven reflexes to microgravity is a long-duration process.

Locomotion of a bioinspired flyer powered by one pair of pitching foils

NASA Astrophysics Data System (ADS)

Zhang, Xiang; He, Guowei; Wang, Shizhao; Zhang, Xing

2018-01-01

We numerically investigate the flight dynamics and aerodynamics of a two-dimensional model for the jellyfishlike ornithopter recently devised by Ristroph and Childress [L. Ristroph and S. Childress, J. R. Soc. Interface 11, 20130992 (2014), 10.1098/rsif.2013.0992]. This simplified model is composed of two rigid thin foils which are forced to pitch in antiphase fashion. The Navier-Stokes equations for the fluid and the dynamics equations for the flyer are solved together in the simulations. We first consider the constrained-flying condition where the flyer model is only allowed to move in the vertical direction. The influences of the control parameters on the hovering performance are studied. With the variations in parameter values, three different locomotion states, i.e., ascending, descending, and approximate hovering, are identified. The wake structures corresponding to these three locomotion states are explored. It is found that the approximate hovering state cannot persist due to the occurrence of wake symmetry breaking after long-time simulation. We then consider the free-flying condition where the motions in three degrees of freedom are allowed. We study the postural stability of a flyer, with its center of gravity located at the geometric center. The responses of the flyer at different locomotion states to physical and numerical perturbations are examined. Our results show that the ascending state is recoverable after the perturbation. The descending state is irrecoverable after the perturbation and a mixed fluttering and tumbling motion which resembles that of a falling card emerges. The approximate hovering state is also irrecoverable and it eventually transits to the ascending state after the perturbation. The research sheds light on the lift-producing mechanism and stability of the flyer and the results are helpful in guiding the design and optimization of the jellyfishlike flying machine.

Mars Exploration Using Biomorphic Flyers

NASA Astrophysics Data System (ADS)

Thakoor, S.; Chahl, J.; Srinivasan, M.; Cabrol, N.; Young, L.; Hine, B.; Zornetzer, S.

Mars imagery obtained by the Mariner, Viking, Pathfinder, Mars Global Surveyor and Mars Odyssey Missions suggests the previous existence of abundant liquid water (considered essential for life as we know it). It is not clear what transpired on the Martian climate to have turned the planet in to the desert that it is today. Developing a comprehensive understanding of the past and present climatic events for our sister planet Mars may provide important information relevant to the future health and well being of our own planet. Following and exploring water flow features is a valuable strategy in the search for extant or extinct life, it satisfies our fundamental scientific curiosity, and could provide answers to the fundamental questions surrounding the question of the origins of life in our solar system. Low altitude air-borne exploration of Mars offers a means for covering large areas, perhaps up to several hundred kilometers, quickly and efficiently. Aerial exploration should provide a close-up birds eye view of the planetary terrain. Exploration that can only be imagined today could become a reality if we develop methods to fly on Mars and navigate through its difficult terrain to image/study sites of interest. Mars offers a substantial challenge to conventional flight due to its thin atmosphere (about a hundredth that on Earth); lack of magnetic compassing for navigation, and the limited telecommunications or navigational infrastructure. To meet and overcome these challenges, we are adapting for Mars exploration principles proven successful in nature to achieve stable flight control and navigation. By incorporating engineering solutions modeled on successful biological solutions we will provide novel and highly effective micro flyer capabilities suitable for aerial surveillance of Mars. We will describe a few example sites on Mars whose exploration absolutely requires the ability to cover several hundred kilometers. We will illustrate how autonomous biomorphic

Insomnia with Objective Short Sleep Duration is Associated with a High Risk for Hypertension

PubMed Central

Vgontzas, Alexandros N.; Liao, Duanping; Bixler, Edward O.; Chrousos, George P.; Vela-Bueno, Antonio

2009-01-01

Study Objectives: To examine the joint effect of insomnia and objective short sleep duration on hypertension risk. Design: Representative cross-sectional study. Setting: Sleep laboratory. Participants: 1,741 men and women randomly selected from central Pennsylvania. Interventions: None. Measurements: Insomnia was defined by a complaint of insomnia with a duration ≥ 1 year, while poor sleep was defined as a complaint of difficulty falling asleep, staying asleep, or early final awakening. Polysomnographic sleep duration was classified into 3 categories: ≥ 6 h sleep (top 50% of the sample); 5-6 h (approximately the third quartile of the sample); and ≤ 5 h (approximately the bottom quartile of the sample). Hypertension was defined based either on blood pressure measures or treatment. We controlled for age, race, sex, body mass index, diabetes, smoking, alcohol use, depression, sleep disordered breathing (SDB), and sampling weight. Results: Compared to the normal sleeping and > 6 h sleep duration group, the highest risk of hypertension was in insomnia with < 5 h sleep duration group (OR [95% CI] 5.1 [2.2, 11.8]), and the second highest in insomnia who slept 5-6 hours (OR 3.5 [1.6, 7.9] P < 0.01). The risk for hypertension was significantly higher, but of lesser magnitude, in poor sleepers with short sleep duration. Conclusions: Insomnia with short sleep duration is associated with increased risk of hypertension, to a degree comparable to that of other common sleep disorders, e.g., SDB. Objective sleep duration may predict the severity of chronic insomnia a prevalent condition whose medical impact has been apparently underestimated. Citation: Vgontzas AN; Liao D; Bixler EO; Chrousos GP; Vela-Bueno A. Insomnia with objective short sleep duration is associated with a high risk for hypertension. SLEEP 2009;32(4):491–497. PMID:19413143

Japanese Space Flyer Unit (SFU) satellite rendezvous

NASA Image and Video Library

1996-01-20

STS072-720-042 (13 Jan. 1996) --- The crew members captured this 70mm view of the Japanese Space Flyer Unit (SFU) just prior to the jettisoning of the solar panels. Later, they used the Remote Manipulator System (RMS) to latch onto the satellite and berth it in the Space Shuttle Endeavour’s aft cargo bay.

The Effect of Detonation Wave Incidence Angle on the Acceleration of Flyers by Explosives Heavily Laden with Inert Additives

NASA Astrophysics Data System (ADS)

Loiseau, Jason; Georges, William; Frost, David; Higgins, Andrew

2015-06-01

The incidence angle of a detonation wave is often assumed to weakly influence the terminal velocity of an explosively driven flyer. For explosives heavily loaded with dense additives, this may not be true due to differences in momentum and energy transfer between detonation products, additive particles, and the flyer. For tangential incidence the particles are first accelerated against the flyer via an expansion fan, whereas they are first accelerated by the detonation wave in the normal case. In the current study we evaluate the effect of normal versus tangential incidence on the acceleration of flyers by nitromethane heavily loaded with a variety of additives. Normal detonation was initiated via an explosively driven slapper. Flyer acceleration was measured with heterodyne laser interferometry (PDV). The influence of wave angle is evaluated by comparing the terminal velocity in the two cases (i.e., normal and grazing) for the heavily loaded mixtures. The decrement in flyer velocity correlated primarily with additive volume fraction and had a weak dependence on additive density or particle size. The Gurney energy of the heterogeneous explosive was observed to increase with flyer mass, presumably due to the timescale over which impinging particles could transfer momentum.

Short Sleep Duration Among Middle School and High School Students - United States, 2015.

PubMed

Wheaton, Anne G; Jones, Sherry Everett; Cooper, Adina C; Croft, Janet B

2018-01-26

Insufficient sleep among children and adolescents is associated with increased risk for obesity, diabetes, injuries, poor mental health, attention and behavior problems, and poor academic performance (1-4). The American Academy of Sleep Medicine has recommended that, for optimal health, children aged 6-12 years should regularly sleep 9-12 hours per 24 hours and teens aged 13-18 years should sleep 8-10 hours per 24 hours (1). CDC analyzed data from the 2015 national, state, and large urban school district Youth Risk Behavior Surveys (YRBSs) to determine the prevalence of short sleep duration (<9 hours for children aged 6-12 years and <8 hours for teens aged 13-18 years) on school nights among middle school and high school students in the United States. In nine states that conducted the middle school YRBS and included a question about sleep duration in their questionnaire, the prevalence of short sleep duration among middle school students was 57.8%, with state-level estimates ranging from 50.2% (New Mexico) to 64.7% (Kentucky). The prevalence of short sleep duration among high school students in the national YRBS was 72.7%. State-level estimates of short sleep duration for the 30 states that conducted the high school YRBS and included a question about sleep duration in their questionnaire ranged from 61.8% (South Dakota) to 82.5% (West Virginia). The large percentage of middle school and high school students who do not get enough sleep on school nights suggests a need for promoting sleep health in schools and at home and delaying school start times to permit students adequate time for sleep.

Childhood Sleep Duration and Quality in Relation to Leptin Concentration in Two Cohort Studies

PubMed Central

Boeke, Caroline E.; Storfer-Isser, Amy; Redline, Susan; Taveras, Elsie M.

2014-01-01

Study Objectives: Poor sleep in childhood is associated with increased obesity risk, possibly by affecting appetite-regulating hormones such as leptin. We examined short- and long-term sleep duration and quality in relation to leptin in two US pediatric cohorts. Design: Analysis of data from two prospective cohort studies. Setting: Population-based. Adolescent polysomnography assessments performed in a clinical research unit. Patients or Participants: Children in Project Viva (n = 655) and adolescents in the Cleveland Children's Sleep & Health Study (n = 502). Interventions: N/A. Measurements and Results: In Project Viva, mothers reported average child sleep duration annually from infancy through age 7, and we measured leptin at ages 3 and 7. In the Cleveland Children's Sleep & Health Study, we collected self-reported sleep duration, polysomnography-derived measures of sleep quality, and fasting leptin at ages 16-19. In sex-stratified linear regression analyses adjusted for sociodemographic characteristics and adiposity, chronic curtailed sleep was associated with lower leptin at age 7 in girls; a one-unit decrease in sleep score was associated with a 0.08 decrease in log leptin (95%CI: 0.01,0.15). The association was stronger in girls with greater adiposity (P = 0.01). Among adolescents, shorter sleep was associated with lower leptin in males; each one-hour decrease in sleep duration was associated with a 0.06 decrease in log leptin (95%CI: 0.00, 0.11). Sleep duration was not associated with leptin at other ages. Sleep quality indices were not associated with leptin. Conclusions: Our results suggest possible age-specific sexual dimorphism in the influence of sleep on leptin, which may partly explain inconsistencies in the literature. Citation: Boeke CE; Storfer-Isser A; Redline S; Taveras EM. Childhood sleep duration and quality in relation to leptin concentration in two cohort studies. SLEEP 2014;37(3):613-620. PMID:24587585

Insomnia with Objective Short Sleep Duration: the Most Biologically Severe Phenotype of the Disorder

PubMed Central

Vgontzas, Alexandros N.; Fernandez-Mendoza, Julio; Liao, Duanping; Bixler, Edward O.

2013-01-01

Summary Until recently, the association of chronic insomnia with significant medical morbidity was not established and its diagnosis was based solely on subjective complaints. We present evidence that insomnia with objective short sleep duration is the most biologically severe phenotype of the disorder, as it is associated with cognitive-emotional and cortical arousal, activation of both limbs of the stress system, and a higher risk for hypertension, impaired heart rate variability, diabetes, neurocognitive impairment, and mortality. Also, it appears that objective short sleep duration is a biological marker of genetic predisposition to chronic insomnia. In contrast, insomnia with objective normal sleep duration is associated with cognitive-emotional and cortical arousal and sleep misperception but not with signs of activation of both limbs of the stress system or medical complications. Furthermore, the first phenotype is associated with unremitting course, whereas the latter is more likely to remit. We propose that short sleep duration in insomnia is a reliable marker of the biological severity and medical impact of the disorder. Objective measures of sleep obtained in the home environment of the patient would become part of the routine assessment of insomnia patients in a clinician’s office setting. We speculate that insomnia with objective short sleep duration has primarily biological roots and may respond better to biological treatments, whereas insomnia with objective normal sleep duration has primarily psychological roots and may respond better to psychological interventions alone. PMID:23419741

Insomnia with objective short sleep duration: the most biologically severe phenotype of the disorder.

PubMed

Vgontzas, Alexandros N; Fernandez-Mendoza, Julio; Liao, Duanping; Bixler, Edward O

2013-08-01

Until recently, the association of chronic insomnia with significant medical morbidity was not established and its diagnosis was based solely on subjective complaints. We present evidence that insomnia with objective short sleep duration is the most biologically severe phenotype of the disorder, as it is associated with cognitive-emotional and cortical arousal, activation of both limbs of the stress system, and a higher risk for hypertension, impaired heart rate variability, diabetes, neurocognitive impairment, and mortality. Also, it appears that objective short sleep duration is a biological marker of genetic predisposition to chronic insomnia. In contrast, insomnia with objective normal sleep duration is associated with cognitive-emotional and cortical arousal and sleep misperception but not with signs of activation of both limbs of the stress system or medical complications. Furthermore, the first phenotype is associated with unremitting course, whereas the latter is more likely to remit. We propose that short sleep duration in insomnia is a reliable marker of the biological severity and medical impact of the disorder. Objective measures of sleep obtained in the home environment of the patient would become part of the routine assessment of insomnia patients in a clinician's office setting. We speculate that insomnia with objective short sleep duration has primarily biological roots and may respond better to biological treatments, whereas insomnia with objective normal sleep duration has primarily psychological roots and may respond better to psychological interventions alone. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of a flyer design to perform plate impact shock-release-shock experiments on explosives

NASA Astrophysics Data System (ADS)

Finnegan, Simon; Ferguson, James; Millett, Jeremy; Goff, Michael

2017-06-01

A flyer design to generate a shock-release-shock loading history within a gas gun target was developed before being used to study the response of an HMX based explosive. The flyer consisted of two flyer plates separated by a vacuum gap. This created a rear free surface that, with correct material choice, allowed the target to release to close to ambient pressure between the initial shock and subsequent re-shock. The design was validated by impacting piezoelectric pin arrays to record the front flyer deformation. Shots were performed on PCTFE targets to record the shock states generated in an inert material prior to subjecting an HMX based explosive to the same loading. The response of the explosive to this loading history was recorded using magnetic particle velocity (PV) gauges embedded within the targets. The behavior during the run to detonation is compared with the response to sustained shocks at similar input pressures.

Extended-duration versus short-duration pharmacological thromboprophylaxis in acutely Ill hospitalized medical patients: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Liew, Aaron Y L; Piran, Siavash; Eikelboom, John W; Douketis, James D

2017-04-01

Extended-duration pharmacological thromboprophylaxis, for at least 28 days, is effective for the prevention of symptomatic venous thromboembolism (VTE) in high-risk surgical patients but is of uncertain benefit in hospitalized medical patients. We aimed to evaluate the efficacy and safety of extended-duration thromboprophylaxis in hospitalized medical patients. We conducted a systematic PubMed, Medline and EMBASE literature search until June 2016 and a meta-analysis of randomized controlled trials which compared extended-duration with short-duration thromboprophylaxis in hospitalized medical patients. Four randomized controlled trials comparing extended-duration prophylaxis (24-47 days) with short-duration prophylaxis (6-14 days) in a total of 34,068 acutely ill hospitalized medical patients were included. When compared with short-duration prophylaxis, extended-duration prophylaxis was associated with a decrease in symptomatic proximal or distal deep vein thrombosis (DVT) [relative risk (RR) = 0.52; 95% confidence interval (Cl): 0.35-0.77: p = 0.001; absolute risk reduction (ARR) = 0.32%, number needed to treat (NNT) = 313], and symptomatic non-fatal pulmonary embolism (RR = 0.61; 95% Cl 0.38-0.99: p = 0.04; ARR = 0.16%; NNT = 625), an increase in major bleeding (RR = 2.08; 95% Cl 1.50-2.90: p < 0.0001, absolute risk increase = 0.41%, number needed to harm = 244), and no significant reduction in VTE-related mortality (RR = 0.69; 95% Cl 0.45-1.06: p = 0.09) or all-cause mortality (RR = 1.00; 95% CI 0.89-1.12; p = 0.95). There was heterogeneity for major bleeding due to results from the APEX trial (no difference between betrixaban and enoxaparin). Compared with short-duration thromboprophylaxis, extended-duration treatment reduces the risk for symptomatic DVT and non-fatal pulmonary embolism. Extended treatment with apixaban, enoxaparin and rivaroxaban but not betrixaban increases the risk for major

A comparison of the Space Station version of ASTROMAG with two free-flyer versions

NASA Astrophysics Data System (ADS)

Green, M. A.

1992-06-01

The Space Station version of ASTROMAG is compared with free-flyer versions of ASTROMAG which could fly on an Atlas 2a rocket and a Delta rocket. Launch with either free-flyer imposes severe weight limits on the magnet and its cryogenic system. Both versions of ASTROMAG magnet which fly on free-flying satellites do not have to be charged more than once during the mission. This permits one to simplify the charging system and the cryogenic system. The helium 2 pump loop which supplies helium to the gas cooled electrical leads can be eliminated in both of the free-flyer versions of the ASTROMAG magnet. The superconducting dipole moment correction coils which are necessary for the magnet to operate on a free-flying satellite are described.

Short Duration Base Heating Test Improvements

NASA Technical Reports Server (NTRS)

Bender, Robert L.; Dagostino, Mark G.; Engel, Bradley A.; Engel, Carl D.

1999-01-01

Significant improvements have been made to a short duration space launch vehicle base heating test technique. This technique was first developed during the 1960's to investigate launch vehicle plume induced convective environments. Recent improvements include the use of coiled nitrogen buffer gas lines upstream of the hydrogen / oxygen propellant charge tubes, fast acting solenoid valves, stand alone gas delivery and data acquisition systems, and an integrated model design code. Technique improvements were successfully demonstrated during a 2.25% scale X-33 base heating test conducted in the NASA/MSFC Nozzle Test Facility in early 1999. Cost savings of approximately an order of magnitude over previous tests were realized due in large part to these improvements.

A novel accelerometry-based algorithm for the detection of step durations over short episodes of gait in healthy elderly.

PubMed

Micó-Amigo, M Encarna; Kingma, Idsart; Ainsworth, Erik; Walgaard, Stefan; Niessen, Martijn; van Lummel, Rob C; van Dieën, Jaap H

2016-04-19

The assessment of short episodes of gait is clinically relevant and easily implemented, especially given limited space and time requirements. BFS (body-fixed-sensors) are small, lightweight and easy to wear sensors, which allow the assessment of gait at relative low cost and with low interference. Thus, the assessment with BFS of short episodes of gait, extracted from dailylife physical activity or measured in a standardised and supervised setting, may add value in the study of gait quality of the elderly. The aim of this study was to evaluate the accuracy of a novel algorithm based on acceleration signals recorded at different human locations (lower back and heels) for the detection of step durations over short episodes of gait in healthy elderly subjects. Twenty healthy elderly subjects (73.7 ± 7.9 years old) walked twice a distance of 5 m, wearing a BFS on the lower back, and on the outside of each heel. Moreover, an optoelectronic three-dimensional (3D) motion tracking system was used to detect step durations. A novel algorithm is presented for the detection of step durations from low-back and heel acceleration signals separately. The accuracy of the algorithm was assessed by comparing absolute differences in step duration between the three methods: step detection from the optoelectronic 3D motion tracking system, step detection from the application of the novel algorithm to low-back accelerations, and step detection from the application of the novel algorithm to heel accelerations. The proposed algorithm successfully detected all the steps, without false positives and without false negatives. Absolute average differences in step duration within trials and across subjects were calculated for each comparison, between low-back accelerations and the optoelectronic system were on average 22.4 ± 7.6 ms (4.0 ± 1.3 % of average step duration), between heel accelerations and the optoelectronic system were on average 20.7 ± 11.8 ms (3.7 ± 1.9 %), and between low

The Prevalence of Short Sleep Duration by Industry and Occupation in the National Health Interview Survey

PubMed Central

Luckhaupt, Sara E.; Tak, SangWoo; Calvert, Geoffrey M.

2010-01-01

Study Objectives: To explore whether employment in industries likely to have non-standard work schedules (e.g., manufacturing and service) and occupations with long work-weeks (e.g., managerial/ professional, sales, and transportation) is associated with an increased risk of short sleep duration. Design: Cross-sectional epidemiologic survey. Setting: Household-based face-to-face survey of civilian, non-institutionalized US residents. Participants: Sample adults interviewed for the National Health Interview Survey in 1985 or 1990 (N = 74,734) or between 2004 and 2007 (N = 110,422). Most analyses focused on civilian employed workers interviewed between 2004 and 2007 (N = 66,099). Interventions: N/A Measurements and Results: The weighted prevalence of self-reported short sleep duration, defined as ≤6 h per day, among civilian employed workers from 2004-2007 was 29.9%. Among industry categories, the prevalence of short sleep duration was greatest for management of companies and enterprises (40.5%), followed by transportation/warehousing (37.1%) and manufacturing (34.8%). Occupational categories with the highest prevalence included production occupations in the transportation/warehousing industry, and installation, maintenance, and repair occupations in both the transportation/warehousing industry and the manufacturing industry. In the combined sample from 1985 and 1990, 24.2% of workers reported short sleep duration; the prevalence of short sleep duration was significantly lower during this earlier time period compared to 2004–2007 for 7 of 8 industrial sectors. Conclusions: Self-reported short sleep duration among US workers varies by industry and occupation, and has increased over the past two decades. These findings suggest the need for further exploration of the relationship between work and sleep, and development of targeted interventions for specific industry/occupation groups. Citation: Luckhaupt SE; Tak S; Calvert GM. The prevalence of short sleep duration

Objective but Not Subjective Short Sleep Duration Associated with Increased Risk for Hypertension in Individuals with Insomnia

PubMed Central

Bathgate, Christina J.; Edinger, Jack D.; Wyatt, James K.; Krystal, Andrew D.

2016-01-01

Study Objectives: To examine the relationship between hypertension prevalence in individuals with insomnia who have short total sleep duration < 6 h or sleep duration ≥ 6 h, using both objective and subjective measures of total sleep duration. Methods: Using a cross-sectional, observational design, 255 adult volunteers (n = 165 women; 64.7%) meeting current diagnostic criteria for insomnia disorder (MAge = 46.2 y, SDAge = 13.7 y) participated in this study at two large university medical centers. Two nights of polysomnography, 2 w of sleep diaries, questionnaires focused on sleep, medical, psychological, and health history, including presence/absence of hypertension were collected. Logistic regressions assessed the odds ratios of hypertension among persons with insomnia with short sleep duration < 6 h compared to persons with insomnia with a sleep duration ≥ 6 h, measured both objectively and subjectively. Results: Consistent with previous studies using objective total sleep duration, individuals with insomnia and short sleep duration < 6 h were associated with a 3.59 increased risk of reporting hypertension as a current medical problem as compared to individuals with insomnia with sleep duration ≥ 6 h. Increased risk for hypertension was independent of major confounding factors frequently associated with insomnia or hypertension. No significant risk was observed using subjectively determined total sleep time groups. Receiver operating characteristic curve analysis found that the best balance of sensitivity and specificity using subjective total sleep time was at a 6-h cutoff, but the area under the receiver operating characteristic curve showed low accuracy and did not have good discriminant value. Conclusions: Objectively measured short sleep duration increased the odds of reporting hypertension more than threefold after adjusting for potential confounders; this relationship was not significant for subjectively measured sleep duration. This research

Short Duration Heat Acclimation in Australian Football Players

PubMed Central

Kelly, Monica; Gastin, Paul B.; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J.

2016-01-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg-1·min-1) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac-]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac-] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key points Some minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat. The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season. Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat

Short Duration Heat Acclimation in Australian Football Players.

PubMed

Kelly, Monica; Gastin, Paul B; Dwyer, Daniel B; Sostaric, Simon; Snow, Rodney J

2016-03-01

This study examined if five sessions of short duration (27 min), high intensity, interval training (HIIT) in the heat over a nine day period would induce heat acclimation in Australian football (AF) players. Fourteen professional AF players were matched for VO2peak (mL·kg(-1)·min(-1)) and randomly allocated into either a heat acclimation (Acc) (n = 7) or Control (Con) group (n = 7). The Acc completed five cycle ergometer HIIT sessions within a nine day period on a cycle ergometer in the heat (38.7 ± 0.5 °C; 34.4 ± 1.3 % RH), whereas Con trained in thermo-neutral conditions (22.3 ± 0.2 °C; 35.8 ± 0. % RH). Four days prior and two days post HIIT participants undertook a 30 min constant load cycling test at 60% V̇O2peak in the heat (37.9 ± 0.1 °C; 28.5 ± 0.7 % RH) during which VO2, blood lactate concentration ([Lac(-)]), heart rate (HR), rating of perceived exertion (RPE), thermal comfort, core and skin temperatures were measured. Heat acclimation resulted in reduced RPE, thermal comfort and [Lac(-)] (all p < 0.05) during the submaximal exercise test in the heat. Heart rate was lower (p = 0.007) after HIIT, in both groups. Heat acclimation did not influence any other measured variables. In conclusion, five short duration HIIT sessions in hot dry conditions induced limited heat acclimation responses in AF players during the in-season competition phase. In practice, the heat acclimation protocol can be implemented in a professional team environment; however the physiological adaptations resulting from such a protocol were limited. Key pointsSome minor heat acclimation adaptations can be induced in professional AF players with five 27 min non-consecutive, short duration HIIT sessions in the heat.The heat acclimation protocol employed in this study was able to be implemented in a professional team sport environment during an actual competitive season.Elevating and maintaining a high core temperature sufficient for heat acclimation likely requires a longer heat

Yield strength measurement of shock-loaded metal by flyer-impact perturbation method

NASA Astrophysics Data System (ADS)

Ma, Xiaojuan; Shi, Zhan

2018-06-01

Yield strength is one of the most important physical properties of a solid material, especially far from its melting line. The flyer-impact perturbation method measures material yield strength on the basis of correlation between the yield strength under shock compression and the damping of oscillatory perturbations in the shape of a shock front passing through the material. We used flyer-impact experiments on targets with machined grooves on the impact surface of shock 6061-T6 aluminum to between 32 and 61 GPa and recorded the evolution of the shock front perturbation amplitude in the sample with electric pins. Simulations using the elastic-plastic model can be matched to the experiments, explaining well the form of the perturbation decay and constraining the yield strength of 6061-T6 aluminum to be 1.31-1.75 GPa. These results are in agreement with values obtained from reshock and release wave profiles. We conclude that the flyer-impact perturbation method is indeed a new means to measure material strength.

Sleep Duration and Quality in Relation to Autonomic Nervous System Measures: The Multi-Ethnic Study of Atherosclerosis (MESA)

PubMed Central

Castro-Diehl, Cecilia; Diez Roux, Ana V.; Redline, Susan; Seeman, Teresa; McKinley, Paula; Sloan, Richard; Shea, Steven

2016-01-01

Study Objectives: Short sleep duration and poor sleep quality are associated with adverse cardiovascular outcomes. Potential pathophysiological mechanisms include sleep-associated alterations in the autonomic nervous system. The objective of this study was to examine the associations of shorter sleep duration and poorer sleep quality with markers of autonomic tone: heart rate (HR), high-frequency HR variability (HF-HRV) and salivary amylase. Methods: Cross-sectional analysis of data from actigraphy-based measures of sleep duration and efficiency and responses to a challenge protocol obtained from 527 adult participants in the Multi-Ethnic Study of Atherosclerosis. Results: Participants who slept fewer than 6 h per night (compared to those who slept 7 h or more per night) had higher baseline HR (fully adjusted model 0.05 log beats/min, 95% confidence interval [CI] 0.01, 0.09) and greater HR orthostatic reactivity (fully adjusted model 0.02 log beats/min, 95% CI 0.002, 0.023). Participants who slept 6 to less than 7 h/night (compared to those who slept 7 h or more per night) had lower baseline HF-HRV (fully adjusted model −0.31 log msec2, 95% CI −0.60, −0.14). Participants with low sleep efficiency had lower baseline HF-HRV than those with higher sleep efficiency (fully adjusted model −0.59 log msec2, 95% CI −1.03, −0.15). Participants with low sleep efficiency had higher baseline levels of amylase than those with higher sleep efficiency (fully adjusted model 0.45 log U/mL, 95% CI 0.04, 0.86). Conclusions: Short sleep duration, low sleep efficiency, and insomnia combined with short sleep duration were associated with markers of autonomic tone that indicate lower levels of cardiac parasympathetic (vagal) tone and/or higher levels of sympathetic tone. Citation: Castro-Diehl C, Roux AV, Redline S, Seeman T, McKinley P, Sloan R, Shea S. Sleep duration and quality in relation to autonomic nervous system measures: the Multi-Ethnic Study of Atherosclerosis (MESA

Method and apparatus for producing durationally short ultraviolet or x-ray laser pulses

DOEpatents

MacGowan, B.J.; Matthews, D.L.; Trebes, J.E.

1987-05-05

A method and apparatus is disclosed for producing ultraviolet or x- ray laser pulses of short duration. An ultraviolet or x-ray laser pulse of long duration is progressively refracted, across the surface of an opaque barrier, by a streaming plasma that is produced by illuminating a solid target with a pulse of conventional line focused high power laser radiation. The short pulse of ultraviolet or x-ray laser radiation, which may be amplified to high power, is separated out by passage through a slit aperture in the opaque barrier.

Time-resolved imaging of flyer dynamics for femtosecond laser-induced backward transfer of solid polymer thin films

NASA Astrophysics Data System (ADS)

Feinaeugle, M.; Gregorčič, P.; Heath, D. J.; Mills, B.; Eason, R. W.

2017-02-01

We have studied the transfer regimes and dynamics of polymer flyers from laser-induced backward transfer (LIBT) via time-resolved shadowgraphy. Imaging of the flyer ejection phase of LIBT of 3.8 μm and 6.4 μm thick SU-8 polymer films on germanium and silicon carrier substrates was performed over a time delay range of 1.4-16.4 μs after arrival of the laser pulse. The experiments were carried out with 150 fs, 800 nm pulses spatially shaped using a digital micromirror device, and laser fluences of up to 3.5 J/cm2 while images were recorded via a CCD camera and a spark discharge lamp. Velocities of flyers found in the range of 6-20 m/s, and the intact and fragmented ejection regimes, were a function of donor thickness, carrier and laser fluence. The crater profile of the donor after transfer and the resulting flyer profile indicated different flyer ejection modes for Si carriers and high fluences. The results contribute to better understanding of the LIBT process, and help to determine experimental parameters for successful LIBT of intact deposits.

Generation of ramp waves using variable areal density flyers

NASA Astrophysics Data System (ADS)

Winter, R. E.; Cotton, M.; Harris, E. J.; Chapman, D. J.; Eakins, D.

2016-07-01

Ramp loading using graded density impactors as flyers in gas-gun-driven plate impact experiments can yield new and useful information about the equation of state and the strength properties of the loaded material. Selective Laser Melting, an additive manufacturing technique, was used to manufacture a graded density flyer, termed the "bed-of-nails" (BON). A 2.5-mm-thick × 99.4-mm-diameter solid disc of stainless steel formed a base for an array of tapered spikes of length 5.5 mm and spaced 1 mm apart. The two experiments to test the concept were performed at impact velocities of 900 and 1100 m/s using the 100-mm gas gun at the Institute of Shock Physics at Imperial College London. In each experiment, a BON flyer was impacted onto a copper buffer plate which helped to smooth out perturbations in the wave profile. The ramp delivered to the copper buffer was in turn transmitted to three tantalum targets of thicknesses 3, 5 and 7 mm, which were mounted in contact with the back face of the copper. Heterodyne velocimetry (Het-V) was used to measure the velocity-time history, at the back faces of the tantalum discs. The wave profiles display a smooth increase in velocity over a period of ˜ 2.5 μs, with no indication of a shock jump. The measured profiles have been analysed to generate a stress vs. volume curve for tantalum. The results have been compared with the predictions of the Sandia National Laboratories hydrocode, CTH.

Immune System Dysregulation, Viral Reactivation and Stress During Short-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, Duane; Sams, Clarence; Crucian, Brian; Mehta, Satish; Stowe, Raymond; Uchakin, Peter; Quiriarte, Heather

2010-01-01

The objective of this NASA Short-Duration Bioastronautics Investigation (SDBI) was to assess spaceflight-associated immune dysregulation. Many previous studies have investigated this phenomenon post-flight, and found altered distribution and function of the peripheral leukocyte populations. Alterations in cytokine production profiles have also been reported. Unfortunately, post-flight data may be altered by the stress associated with high-G re-entry and readaptation to unit gravity following deconditioning. Therefore, the current study collected blood and saliva samples from crewmembers immediately before landing, and returned those samples to Earth for terrestrial analysis. Assays include peripheral comprehensive immunophenotype, T cell function, cytokine profiles, viral-specific immunity, latent viral reactivation (EBV, CMV, VZV), and stress hormone measurements. A total of 18 short duration crewmembers completed the study and the final data will be presented.

Objectively measured short sleep duration and later sleep midpoint in pregnancy are associated with a higher risk of gestational diabetes.

PubMed

Facco, Francesca L; Grobman, William A; Reid, Kathryn J; Parker, Corette B; Hunter, Shannon M; Silver, Robert M; Basner, Robert C; Saade, George R; Pien, Grace W; Manchanda, Shalini; Louis, Judette M; Nhan-Chang, Chia-Ling; Chung, Judith H; Wing, Deborah A; Simhan, Hyagriv N; Haas, David M; Iams, Jay; Parry, Samuel; Zee, Phyllis C

2017-10-01

Experimental and epidemiologic data suggest that among nonpregnant adults, sleep duration may be an important risk factor for chronic disease. Although pregnant women commonly report poor sleep, few studies objectively evaluated the quality of sleep in pregnancy or explored the relationship between sleep disturbances and maternal and perinatal outcomes. Our objective was to examine the relationship between objectively assessed sleep duration, timing, and continuity (measured via wrist actigraphy) and maternal cardiovascular and metabolic morbidity specific to pregnancy. This was a prospective cohort study of nulliparous women. Women were recruited between 16 0/7 and 21 6/7 weeks' gestation. They were asked to wear a wrist actigraphy monitor and complete a daily sleep log for a period of 7 consecutive days. The primary sleep exposure variables were the averages of the following over the total valid nights (minimum 5, maximum 7 nights): short sleep duration during the primary sleep period (<7 h/night), late sleep midpoint (midpoint between sleep onset and sleep offset >5 am), and top quartile of minutes of wake time after sleep onset and sleep fragmentation index. The primary outcomes of interest were a composite of hypertensive disorders of pregnancy (mild, severe, or superimposed preeclampsia; eclampsia; or antepartum gestational hypertension) and gestational diabetes mellitus. We used χ 2 tests to assess associations between sleep variables and categorical baseline characteristics. Crude odds ratios and 95% confidence intervals were estimated from univariate logistic regression models to characterize the magnitude of the relationship between sleep characteristics and hypertensive disorders of pregnancy and gestational diabetes. For associations significant in univariate analysis, multiple logistic regression was used to explore further the association of sleep characteristics with pregnancy outcomes. In all, 901 eligible women consented to participate; 782

Objective but Not Subjective Short Sleep Duration Associated with Increased Risk for Hypertension in Individuals with Insomnia.

PubMed

Bathgate, Christina J; Edinger, Jack D; Wyatt, James K; Krystal, Andrew D

2016-05-01

To examine the relationship between hypertension prevalence in individuals with insomnia who have short total sleep duration < 6 h or sleep duration ≥ 6 h, using both objective and subjective measures of total sleep duration. Using a cross-sectional, observational design, 255 adult volunteers (n = 165 women; 64.7%) meeting current diagnostic criteria for insomnia disorder (MAge = 46.2 y, SDAge = 13.7 y) participated in this study at two large university medical centers. Two nights of polysomnography, 2 w of sleep diaries, questionnaires focused on sleep, medical, psychological, and health history, including presence/absence of hypertension were collected. Logistic regressions assessed the odds ratios of hypertension among persons with insomnia with short sleep duration < 6 h compared to persons with insomnia with a sleep duration ≥ 6 h, measured both objectively and subjectively. Consistent with previous studies using objective total sleep duration, individuals with insomnia and short sleep duration < 6 h were associated with a 3.59 increased risk of reporting hypertension as a current medical problem as compared to individuals with insomnia with sleep duration ≥ 6 h. Increased risk for hypertension was independent of major confounding factors frequently associated with insomnia or hypertension. No significant risk was observed using subjectively determined total sleep time groups. Receiver operating characteristic curve analysis found that the best balance of sensitivity and specificity using subjective total sleep time was at a 6-h cutoff, but the area under the receiver operating characteristic curve showed low accuracy and did not have good discriminant value. Objectively measured short sleep duration increased the odds of reporting hypertension more than threefold after adjusting for potential confounders; this relationship was not significant for subjectively measured sleep duration. This research supports emerging evidence that insomnia with objective

Short sleep duration and childhood obesity: cross-sectional analysis in Peru and patterns in four developing countries.

PubMed

Carrillo-Larco, Rodrigo M; Bernabé-Ortiz, Antonio; Miranda, J Jaime

2014-01-01

We aimed to describe the patterns of nutritional status and sleep duration in children from Ethiopia, India, Peru and Vietnam; to assess the association between short sleep duration and overweight and obesity, and if this was similar among boys and girls in Peru. Analysis of the Young Lives Study, younger cohort, third round. In Ethiopia there were 1,999 observations, 2,011, 2,052 and 2,000 in India, Peru and Vietnam, respectively. Analyses included participants with complete data for sleep duration, BMI, sex and age; missing data: 5.9% (Ethiopia), 4.1% (India), 6.0% (Peru) and 4.5% (Vietnam). Exposure was sleep duration per day: short (<10 hours) versus regular (10-11 hours). Outcome was overweight and obesity. Multivariable analyses were conducted using a hierarchical approach to assess the effect of variables at different levels. Overweight/obesity prevalence was 0.5%/0.2% (Ethiopia), 1.3%/0.3% (India), 6.1%/2.8% (Vietnam), and 15.8%/5.4% (Peru). Only Peruvian data was considered to explore the association between short sleep duration and overweight and obesity, with 1,929 children, aged 7.9±0.3 years, 50.3% boys. Short and regular sleep duration was 41.6% and 55.6%, respectively. Multivariable models showed that obesity was 64% more prevalent among children with short sleep duration, an estimate that lost significance after controlling for individual- and family-related variables (PR: 1.15; 95%CI: 0.81-1.64). Gender was an effect modifier of the association between short sleep duration and overweight (p = 0.030) but not obesity (p = 0.533): the prevalence ratio was greater than one across all the models for boys, yet it was less than one for girls. Childhood overweight and obesity have different profiles across developing settings. In a sample of children living in resource-limited settings in Peru there is no association between short sleep duration and obesity; the crude association was slightly attenuated by children-related variables but strongly

Wright Flyer detail in Bob McCall's Centennial of Flight mural

NASA Image and Video Library

2003-06-05

The mural was created to celebrate the achievements of Wilbur and Orville Wright and to commemorate a century of powered flight. Central to the composition is the 1903 Wright Flyer. "On Dec. 17, 1903, the Wright brothers inaugurated the aerial age with their successful first flights of a heavier-than-air flying machine at Kitty Hawk, N.C. This airplane, known as the Wright Flyer, sometimes referred to as the Kitty Hawk Flyer, was the product of a sophisticated four-year program of research and development conducted by Wilbur and Orville Wright beginning in 1899. During the Wrights' design and construction of their experimental aircraft, they also pioneered many of the basic tenets and techniques of modern aeronautical engineering, such as the use of a wind tunnel and flight testing as design tools. Their seminal accomplishment encompassed not only the breakthrough first flight of an airplane, but also the equally important achievement of establishing the foundation of aeronautical engineering." Dr. Peter Jakab, Curator of Aviation, National Air and Space Museum, Smithsonian Institution "Celebrating One Hundred Years of Powered Flight, 1903-2003", documents many significant achievements in aeronautics and space flight from the dawn of powered flight to the present. Historic aircraft and spacecraft serve as the backdrop, highlighting six figures representing the human element that made these milestones possible. These figures stand, symbolically supported by the words of Wilbur Wright, "It is my belief that flight is possible…" The quote was taken from a letter written to his father on September 3rd, 1900, announcing Wilbur's intention to make "some experiments with a flying machine" at Kitty Hawk, North Carolina. "This year, Bob is helping us commemorate the Centennial of Flight with a beautiful mural slated for placement in our Dryden Flight Research Center that documents the history of flight from the Wright Flyer to the International Space Station. We should

Factors associated with sleep duration in Brazilian high school students.

PubMed

Gomes Felden, Érico Pereira; Barbosa, Diego Grasel; Junior, Geraldo Jose Ferrari; Santos, Manoella De Oliveira; Pelegrini, Andreia; Silva, Diego Augusto Santos

2017-01-01

The aim of this study was to investigate the factors associated with short sleep duration on southern Brazilian high school students. Our study was comprised of 1,132 adolescents aged 14 to 19 years, enrolled in public high schools in São José, Brazil. The students answered a questionnaire about working (work and workload), health perception, smoking, school schedule, sleep (duration and daytime sleepiness), and socio-demographics data. The results showed that more than two thirds of adolescent workers had short sleep duration (76.7%), and those with a higher workload (more than 20 hours) had a shorter sleep duration (7.07 hours) compared to non-workers (7.83 hours). In the analysis of factors associated with short sleep duration, adolescents who worked (OR = 2.12, 95% CI 1.53 to 2.95) were more likely to have short sleep duration compared to those who did not work. In addition, older adolescents (17-19 years) and students with poor sleep quality were 40% and 55% more likely to have short sleep duration compared to younger adolescents (14-16 years) and students with good sleep quality, respectively. Adolescents with daytime sleepiness were more likely to have short sleep duration (OR = 1.49, 95% CI 1.06 to 2.07) compared to those without excessive daytime sleepiness. In addition students of the morning shift (OR = 6.02, 95% CI 4.23 to 8.57) and evening shift (OR = 2.16, 95% CI 1.45 to 3.22) were more likely to have short sleep duration compared to adolescents of the afternoon shift. Thereby adolescents who are workers, older, attended morning and evening classes and have excessive daytime sleepiness showed risk factors for short sleep duration. In this sense, it is pointed out the importance of raising awareness of these risk factors for short sleep duration of students from public schools from São José, located in southern Brazil.

The prevalence of short sleep duration by industry and occupation in the National Health Interview Survey.

PubMed

Luckhaupt, Sara E; Tak, SangWoo; Calvert, Geoffrey M

2010-02-01

To explore whether employment in industries likely to have non-standard work schedules (e.g., manufacturing and service) and occupations with long work-weeks (e.g., managerial/professional, sales, and transportation) is associated with an increased risk of short sleep duration. Cross-sectional epidemiologic survey. Household-based face-to-face survey of civilian, non-institutionalized US residents. Sample adults interviewed for the National Health Interview Survey in 1985 or 1990 (N = 74,734) or between 2004 and 2007 (N = 110,422). Most analyses focused on civilian employed workers interviewed between 2004 and 2007 (N = 66,099). N/A. The weighted prevalence of self-reported short sleep duration, defined as < or = 6 h per day, among civilian employed workers from 2004-2007 was 29.9%. Among industry categories, the prevalence of short sleep duration was greatest for management of companies and enterprises (40.5%), followed by transportation/warehousing (37.1%) and manufacturing (34.8%). Occupational categories with the highest prevalence included production occupations in the transportation/warehousing industry, and installation, maintenance, and repair occupations in both the transportation/warehousing industry and the manufacturing industry. In the combined sample from 1985 and 1990, 24.2% of workers reported short sleep duration; the prevalence of short sleep duration was significantly lower during this earlier time period compared to 2004-2007 for 7 of 8 industrial sectors. Self-reported short sleep duration among US workers varies by industry and occupation, and has increased over the past two decades. These findings suggest the need for further exploration of the relationship between work and sleep, and development of targeted interventions for specific industry/occupation groups.

Cognitive Abilities Explaining Age-Related Changes in Time Perception of Short and Long Durations

ERIC Educational Resources Information Center

Zelanti, Pierre S.; Droit-Volet, Sylvie

2011-01-01

The current study investigated how the development of cognitive abilities explains the age-related changes in temporal judgment over short and long duration ranges from 0.5 to 30 s. Children (5- and 9-year-olds) as well as adults were given a temporal bisection task with four different duration ranges: a duration range shorter than 1 s, two…

Racial Differences in Self-Reports of Short Sleep Duration in an Urban-Dwelling Environment

PubMed Central

McNeely, Jessica M.; Shah, Mauli T.; Evans, Michele K.; Zonderman, Alan B.

2015-01-01

Objectives. To explore whether there are differences in sleep duration between blacks and whites residing in similar urban neighborhoods and examine whether the relationship between sleep durations and sociodemographic and/or health indices are consistent for blacks and whites. Methods. A total of 1,207 participants from the Healthy Aging in Neighborhoods of Disparities across the Life Span study (age: mean = 47, standard deviation = 8.74). Sleep duration was assessed by a self-report of hours of nightly sleep in the past month. Sociodemographic measures included age, sex, education, poverty status, and perceived neighborhood disorder. Health status was assessed using measures of vigilance, depression, perceived stress, coronary artery disease, diabetes, blood pressure, and inflammation. Results. There were no significant racial group differences in sleep duration. Whites, however, were more likely than blacks to report sleep durations of <6/6–7hr compared with >7hr with increasing stress and education levels. Blacks were more likely than whites to report short sleep durations (i.e., 6–7hr vs. >7hr of sleep) with increasing inflammation levels. Discussion. Although racial disparities in sleep duration are minimized when the environment is equivalent between blacks and whites, the underlying demographic and health explanations for short sleep durations may vary between whites and blacks. PMID:24285771

Method and apparatus for producing durationally short ultraviolet or X-ray laser pulses

DOEpatents

MacGowan, Brian J.; Matthews, Dennis L.; Trebes, James E.

1988-01-01

A method and apparatus is disclosed for producing ultraviolet or X-ray laser pulses of short duration (32). An ultraviolet or X-ray laser pulse of long duration (12) is progressively refracted, across the surface of an opaque barrier (28), by a streaming plasma (22) that is produced by illuminating a solid target (16, 18) with a pulse of conventional line focused high power laser radiation (20). The short pulse of ultraviolet or X-ray laser radiation (32), which may be amplified to high power (40, 42), is separated out by passage through a slit aperture (30) in the opaque barrier (28).

Short Sleep Duration and Poor Sleep Quality Increase the Risk of Diabetes in Japanese Workers With No Family History of Diabetes

PubMed Central

Kita, Toshiko; Yoshioka, Eiji; Satoh, Hiroki; Saijo, Yasuaki; Kawaharada, Mariko; Okada, Eisaku; Kishi, Reiko

2012-01-01

OBJECTIVE To investigate whether a difference in the risk for diabetes exists in Japanese workers with regard to sleep duration/quality and the presence or absence of a family history of diabetes (FHD). RESEARCH DESIGN AND METHODS The researchers conducted a prospective, occupational-based study of local government employees in Sapporo, Japan. Between April 2003 and March 2004, 3,570 nondiabetic participants, aged 35–55 years, underwent annual health checkups and completed a self-administered questionnaire that included information on sleep duration/quality and FHD at baseline. Having diabetes was defined as taking medication for diabetes or a fasting plasma glucose level of ≥126 mg/dL at follow-up (2007–2008). RESULTS A total of 121 (3.4%) new cases of diabetes were reported. In multivariate logistic regression models of workers without an FHD, and after adjustment for potential confounding factors, the odds ratio (95% CI) for developing diabetes was 5.37 (1.38–20.91) in those with a sleep duration of ≤5 h compared with those with a sleep duration of >7 h. Other risk factors were awakening during the night (5.03 [1.43–17.64]), self-perceived insufficient sleep duration (6.76 [2.09–21.87]), and unsatisfactory overall quality of sleep (3.71 [1.37–10.07]). In subjects with an FHD, these associations were either absent or weaker. CONCLUSIONS The current study shows that poor sleep is associated with a higher risk of developing diabetes in workers without an FHD. Promoting healthy sleeping habits may be effective for preventing the development of diabetes in people without an FHD. PMID:22210572

Sleep Duration and Quality in Pregnant Women: A Cross-Sectional Survey in China.

PubMed

Xu, Xianglong; Liu, Dengyuan; Zhang, Zhangyi; Sharma, Manoj; Zhao, Yong

2017-07-20

Objectives: Good maternal health and fetal development require sufficient and good quality of sleep during pregnancy. This study investigated sleep duration and quality in pregnant women, assessing factors with possibly influence on sleep. Method: A cross-sectional survey was conducted on pregnant women between June and August in 2015 in 16 hospitals in five provinces in China. A total of 2345 pregnant women aged 18 years and older were surveyed. Insufficient sleeping duration was defined as sleeping of less than 7 h per day. Excessive sleep duration was defined as sleeping of more than 9 h per day. Results: A total of 561 (23.9%) participants reported insufficient sleeping duration, whereas 485 (20.9%) claimed excessive sleep duration. A total of 358 (15.2%) of pregnant women reported problems regarding sleep quality. Compared to pregnant women with sufficient sleeping duration, those with insufficient sleeping duration were prone to have poor sleep quality, whereas those with excessive sleeping duration featured low possibility of poor sleep quality. High-risk groups of insufficient sleep duration include women of Han nationality, with siblings, in their first trimester of pregnancy, receiving care in low-capacity/quality hospital settings, and with daily or 1-3 days of secondhand smoke exposure. High-risk groups of excessive sleep duration include women living in rural areas, unemployed, in their third trimester of pregnancy, and receiving care in medium-capacity/quality hospital settings. High-risk groups of poor sleep quality include women of non-Han nationality, low income level, in their third trimester of pregnancy, and with insufficient sleep duration. Conclusions: Insufficient/excessive sleep duration and poor sleep quality commonly occur during pregnancy in China. Findings provide a better understanding of the influencing factors of insufficient/excessive sleep duration and poor quality of sleep. These findings have some implications for future

Sleep Duration and Quality in Pregnant Women: A Cross-Sectional Survey in China

PubMed Central

Liu, Dengyuan; Zhang, Zhangyi; Zhao, Yong

2017-01-01

Objectives: Good maternal health and fetal development require sufficient and good quality of sleep during pregnancy. This study investigated sleep duration and quality in pregnant women, assessing factors with possibly influence on sleep. Method: A cross-sectional survey was conducted on pregnant women between June and August in 2015 in 16 hospitals in five provinces in China. A total of 2345 pregnant women aged 18 years and older were surveyed. Insufficient sleeping duration was defined as sleeping of less than 7 h per day. Excessive sleep duration was defined as sleeping of more than 9 h per day. Results: A total of 561 (23.9%) participants reported insufficient sleeping duration, whereas 485 (20.9%) claimed excessive sleep duration. A total of 358 (15.2%) of pregnant women reported problems regarding sleep quality. Compared to pregnant women with sufficient sleeping duration, those with insufficient sleeping duration were prone to have poor sleep quality, whereas those with excessive sleeping duration featured low possibility of poor sleep quality. High-risk groups of insufficient sleep duration include women of Han nationality, with siblings, in their first trimester of pregnancy, receiving care in low-capacity/quality hospital settings, and with daily or 1–3 days of secondhand smoke exposure. High-risk groups of excessive sleep duration include women living in rural areas, unemployed, in their third trimester of pregnancy, and receiving care in medium-capacity/quality hospital settings. High-risk groups of poor sleep quality include women of non-Han nationality, low income level, in their third trimester of pregnancy, and with insufficient sleep duration. Conclusions: Insufficient/excessive sleep duration and poor sleep quality commonly occur during pregnancy in China. Findings provide a better understanding of the influencing factors of insufficient/excessive sleep duration and poor quality of sleep. These findings have some implications for future

Cumulative Association of Obstructive Sleep Apnea Severity and Short Sleep Duration with the Risk for Hypertension

PubMed Central

Priou, Pascaline; Le Vaillant, Marc; Meslier, Nicole; Paris, Audrey; Pigeanne, Thierry; Nguyen, Xuan-Lan; Alizon, Claire; Bizieux-Thaminy, Acya; Leclair-Visonneau, Laurene; Humeau, Marie-Pierre; Gagnadoux, Frédéric

2014-01-01

Obstructive sleep apnea (OSA) and short sleep duration are individually associated with an increased risk for hypertension (HTN). The aim of this multicenter cross-sectional study was to test the hypothesis of a cumulative association of OSA severity and short sleep duration with the risk for prevalent HTN. Among 1,499 patients undergoing polysomnography for suspected OSA, 410 (27.3%) previously diagnosed as hypertensive and taking antihypertensive medication were considered as having HTN. Patients with total sleep time (TST) <6 h were considered to be short sleepers. Logistic regression procedures were performed to determine the independent association of HTN with OSA and sleep duration. Considering normal sleepers (TST ≥6 h) without OSA as the reference group, the odds ratio (OR) (95% confidence intervals) for having HTN was 2.51 (1.35–4.68) in normal sleepers with OSA and 4.37 (2.18–8.78) in short sleepers with OSA after adjustment for age, gender, obesity, diabetes, depression, current smoking, use of thyroid hormones, daytime sleepiness, poor sleep complaint, time in bed, sleep architecture and fragmentation, and study site. The risk for HTN appeared to present a cumulative association with OSA severity and short sleep duration (p<0.0001 for linear trend). The higher risk for HTN was observed in short sleepers with severe OSA (AHI ≥30) (OR, 4.29 [2.03–9.07]). In patients investigated for suspected OSA, sleep-disordered breathing severity and short sleep duration have a cumulative association with the risk for prevalent HTN. Further studies are required to determine whether interventions to optimize sleep may contribute to lower BP in patients with OSA. PMID:25531468

Short Sleep Duration and Childhood Obesity: Cross-Sectional Analysis in Peru and Patterns in Four Developing Countries

PubMed Central

Carrillo-Larco, Rodrigo M.; Bernabé-Ortiz, Antonio; Miranda, J. Jaime

2014-01-01

Background We aimed to describe the patterns of nutritional status and sleep duration in children from Ethiopia, India, Peru and Vietnam; to assess the association between short sleep duration and overweight and obesity, and if this was similar among boys and girls in Peru. Methods and Findings Analysis of the Young Lives Study, younger cohort, third round. In Ethiopia there were 1,999 observations, 2,011, 2,052 and 2,000 in India, Peru and Vietnam, respectively. Analyses included participants with complete data for sleep duration, BMI, sex and age; missing data: 5.9% (Ethiopia), 4.1% (India), 6.0% (Peru) and 4.5% (Vietnam). Exposure was sleep duration per day: short (<10 hours) versus regular (10–11 hours). Outcome was overweight and obesity. Multivariable analyses were conducted using a hierarchical approach to assess the effect of variables at different levels. Overweight/obesity prevalence was 0.5%/0.2% (Ethiopia), 1.3%/0.3% (India), 6.1%/2.8% (Vietnam), and 15.8%/5.4% (Peru). Only Peruvian data was considered to explore the association between short sleep duration and overweight and obesity, with 1,929 children, aged 7.9±0.3 years, 50.3% boys. Short and regular sleep duration was 41.6% and 55.6%, respectively. Multivariable models showed that obesity was 64% more prevalent among children with short sleep duration, an estimate that lost significance after controlling for individual- and family-related variables (PR: 1.15; 95%CI: 0.81–1.64). Gender was an effect modifier of the association between short sleep duration and overweight (p = 0.030) but not obesity (p = 0.533): the prevalence ratio was greater than one across all the models for boys, yet it was less than one for girls. Conclusions Childhood overweight and obesity have different profiles across developing settings. In a sample of children living in resource-limited settings in Peru there is no association between short sleep duration and obesity; the crude association was slightly

Interaction of sleep quality and sleep duration on glycemic control in patients with type 2 diabetes mellitus.

PubMed

Tang, Yunzhao; Meng, Lingling; Li, Daiqing; Yang, Min; Zhu, Yanjuan; Li, Chenguang; Jiang, Zhenhuan; Yu, Ping; Li, Zhu; Song, Hongna; Ni, Changlin

2014-01-01

Copious evidence from epidemiological and laboratory studies has revealed that sleep status is associated with glucose intolerance, insulin resistance, thus increasing the risk of developing type 2 diabetes. The aim of this study was to reveal the interaction of sleep quality and sleep quantity on glycemic control in patients with type 2 diabetes mellitus. From May 2013 to May 2014, a total of 551 type 2 diabetes patients in Tianjin Metabolic Diseases Hospital were enrolled. Blood samples were taken to measure glycosylated hemoglobin (HbA1c), and all the patients completed the Chinese version of the Pittsburgh Sleep Quality Index (PSQI) questionnaire to evaluate their sleep status. "Good sleep quality" was defined as PQSI <5, "average sleep quality" was defined as PQSI 6-8, and "poor sleep quality" was defined as PQSI >8. Poor glycemic control was defined as HbA1c ≥7%. Sleep quantity was categorized as <6, 6-8, and >8 hours/night. Short sleep time was defined as sleep duration <6 hours/night. In the poor glycemic control group, the rate of patients who had insufficient sleep was much higher than that in the other group (χ(2) = 11.16, P = 0.037). The rate of poor sleep quality in poor glycemic control group was much greater than that in the average control group (χ(2) = 9.79, P = 0.007). After adjusted by gender, age, body mass index, and disease duration, the adjusted PSQI score's OR was 1.048 (95% CI 1.007-1.092, P = 0.023) for HbA1c level. The sleep duration's OR was 0.464 (95% CI 0.236-0.912, P = 0.026) for HbA1c level. One-way analysis of variance showed that the poor sleep quality group had the highest homeostasis model assessment-insulin resistance (P < 0.01). Inadequate sleep, in both quality and quantity, should be regarded as a plausible risk factor for glycemic control in type 2 diabetes. Poor sleep might bring much more serious insulin resistance and could be the reason for bad glycemic control. A good night's sleep should be seen as a critical

1. Photocopy of engraved flyer (from the collection of Dr. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Photocopy of engraved flyer (from the collection of Dr. Margaret Ballard, Union, West Virginia) H. Bartsch, engraver late 19th century AERIAL VIEW OF TOWN AND ADVERTISING SLOGANS - Red Sulphur Springs, Route 12, Salt Sulphur Springs, Monroe County, WV

Magnetic Flyer Facility Correlation and UGT Simulation

DTIC Science & Technology

1978-05-01

AND UGT SIMULATION (U) Kaman Sciences Corporation L ~ P.O. Box 7463 I Colorado Springs, Colcerado 80933 ý4 May 1978DC Final Report CONTRACT No. DNA O01...selected underground test ( UGT ) environment on 3DQP; and, (2) To correlate the magnetically driven flyer plate facilities of VKSC with those of the...tailored to matcb the pressure vs. time anid total impulse measurements obtained on UGT events. This matching of experi- mental data required considerable

Racial differences in self-reports of short sleep duration in an urban-dwelling environment.

PubMed

Gamaldo, Alyssa A; McNeely, Jessica M; Shah, Mauli T; Evans, Michele K; Zonderman, Alan B

2015-07-01

To explore whether there are differences in sleep duration between blacks and whites residing in similar urban neighborhoods and examine whether the relationship between sleep durations and sociodemographic and/or health indices are consistent for blacks and whites. A total of 1,207 participants from the Healthy Aging in Neighborhoods of Disparities across the Life Span study (age: mean = 47, standard deviation = 8.74). Sleep duration was assessed by a self-report of hours of nightly sleep in the past month. Sociodemographic measures included age, sex, education, poverty status, and perceived neighborhood disorder. Health status was assessed using measures of vigilance, depression, perceived stress, coronary artery disease, diabetes, blood pressure, and inflammation. There were no significant racial group differences in sleep duration. Whites, however, were more likely than blacks to report sleep durations of <6/6-7 hr compared with >7 hr with increasing stress and education levels. Blacks were more likely than whites to report short sleep durations (i.e., 6-7 hr vs. >7 hr of sleep) with increasing inflammation levels. Although racial disparities in sleep duration are minimized when the environment is equivalent between blacks and whites, the underlying demographic and health explanations for short sleep durations may vary between whites and blacks. Published by Oxford University Press on behalf of the Gerontological Society of America 2013.

The insomnia with short sleep duration phenotype: an update on it's importance for health and prevention.

PubMed

Fernandez-Mendoza, Julio

2017-01-01

It was first proposed in the late 1990s that objective markers of sleep disturbance could serve as an index of the biological severity of insomnia. In 2013, a heuristic model of two insomnia phenotypes based on objective sleep duration was proposed. Herein, we review the studies conducted in the past 3 years on the insomnia with short sleep duration phenotype and its implications for a clinical research agenda. Studies have shown that insomnia with objective short sleep duration is associated with physiologic hyperarousal and cardiometabolic and neurocognitive morbidity, whereas insomnia with normal sleep duration is not. Both insomnia phenotypes are associated with psychiatric morbidity albeit through different psychobiological mechanisms. Novel recent studies have included occupational outcomes, developmental approaches, at-home objective sleep testing, diagnostic accuracy measures, and response to cognitive-behavioral treatment. Accumulating evidence in the past years has continued to support that insomnia with short sleep duration is a more severe phenotype of the disorder associated with physiologic changes, significant morbidity and mortality and, potentially, a differential response to treatment.

Restoring normoglycaemia by use of a very low calorie diet in long- and short-duration Type 2 diabetes.

PubMed

Steven, S; Taylor, R

2015-09-01

To establish whether an 8-week very-low-calorie diet could improve glycaemic control in Type 2 diabetes of long duration. A total of 29 people with Type 2 diabetes [short-duration group (diabetes duration < 4 years), n = 15; long-duration group (diabetes duration > 8 years), n = 14] completed an 8-week very-low-calorie diet, with assessments of fasting anthropometry, blood tests and blood pressure at baseline and weeks 1, 4 and 8 of the diet. Similar weight loss was achieved in the short- and long-duration groups (14.8 ± 0.8% and 14.4 ± 0.7% respectively; P = 0.662). The glucose response to acute calorie restriction was heterogeneous in the long-duration group with some responding similarly to those in the short-duration group, some responding, but only slowly, and others not responding at all. Overall, HbA1c concentration in the short- vs. long-duration groups fell to 44 ± 2 vs. 64 ± 6 mmol/l (6.2 ± 0.2 vs. 8.0 ± 0.5%; P = 0.002). Fasting plasma glucose levels decreased to 5.8 ± 0.2 vs. 8.4 ± 1.1 mmol/l (P = 0.024) respectively. A total of 87% of the short-duration group and 50% of the long-duration group achieved non-diabetic fasting plasma glucose levels at week 8. Clinically significant improvements in blood pressure and lipid profile were seen regardless of diabetes duration. In people with Type 2 diabetes of > 8 years' duration, a therapeutic trial of a very-low-calorie diet may be undertaken with a 50% chance of achieving non-diabetic fasting glucose levels off all antidiabetic therapies. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.

Short-term memory for event duration: modality specificity and goal dependency.

PubMed

Takahashi, Kohske; Watanabe, Katsumi

2012-11-01

Time perception is involved in various cognitive functions. This study investigated the characteristics of short-term memory for event duration by examining how the length of the retention period affects inter- and intramodal duration judgment. On each trial, a sample stimulus was followed by a comparison stimulus, after a variable delay period (0.5-5 s). The sample and comparison stimuli were presented in the visual or auditory modality. The participants determined whether the comparison stimulus was longer or shorter than the sample stimulus. The distortion pattern of subjective duration during the delay period depended on the sensory modality of the comparison stimulus but was not affected by that of the sample stimulus. When the comparison stimulus was visually presented, the retained duration of the sample stimulus was shortened as the delay period increased. Contrarily, when the comparison stimulus was presented in the auditory modality, the delay period had little to no effect on the retained duration. Furthermore, whenever the participants did not know the sensory modality of the comparison stimulus beforehand, the effect of the delay period disappeared. These results suggest that the memory process for event duration is specific to sensory modality and that its performance is determined depending on the sensory modality in which the retained duration will be used subsequently.

Working hours and sleep duration in midlife as determinants of health-related quality of life among older businessmen.

PubMed

von Bonsdorff, Mikaela Birgitta; Strandberg, Arto; von Bonsdorff, Monika; Törmäkangas, Timo; Pitkälä, Kaisu H; Strandberg, Timo E

2017-01-25

Long working hours and short sleep duration are associated with a range of adverse health consequences. However, the combined effect of these two exposures on health-related quality of life (HRQoL) has not been investigated. We studied white men born between 1919 and 1934 in the Helsinki Businessmen Study (HBS, initial n = 3,490). Data on clinical variables, self-rated health (SRH), working hours and sleep duration in 1974, and RAND-36 (SF-36) HRQoL survey in the year 2000 were available for 1,527 men. Follow-up time was 26 years. By combining working hours and sleep duration, four categories were formed: (i) normal work (≤50 hours/week) and normal sleep (>47 hours/week); (ii) long work (>50 hours/week) and normal sleep; (iii) normal work and short sleep (≤47 hours/week); and (iv) long work and short sleep. The association with RAND-36 domains was examined using multiple linear regression models adjusted for age, smoking and SRH. Compared to those with normal work and sleep in midlife, men with long work and short sleep had poorer RAND-36 scores for physical functioning, vitality and general health, and those with long work and normal sleep had poorer scores for physical functioning in old age. Adjustment for midlife smoking and SRH attenuated the associations, but the one for long work and short sleep and physical functioning remained significant (difference in mean physical functioning score −4.58, 95% confidence interval −9.00 to −0.15). Businessmen who had long working hours coupled with short sleep duration in midlife had poorer physical health in old age. © The Author 2016. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com

A NARROW SHORT-DURATION GRB JET FROM A WIDE CENTRAL ENGINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duffell, Paul C.; Quataert, Eliot; MacFadyen, Andrew I., E-mail: duffell@berkeley.edu

2015-11-01

We use two-dimensional relativistic hydrodynamic numerical calculations to show that highly collimated relativistic jets can be produced in neutron star merger models of short-duration gamma-ray bursts (GRBs) without the need for a highly directed engine or a large net magnetic flux. Even a hydrodynamic engine generating a very wide sustained outflow on small scales can, in principle, produce a highly collimated relativistic jet, facilitated by a dense surrounding medium that provides a cocoon surrounding the jet core. An oblate geometry to the surrounding gas significantly enhances the collimation process. Previous numerical simulations have shown that the merger of two neutronmore » stars produces an oblate, expanding cloud of dynamical ejecta. We show that this gas can efficiently collimate the central engine power much like the surrounding star does in long-duration GRB models. For typical short-duration GRB central engine parameters, we find jets with opening angles of an order of 10° in which a large fraction of the total outflow power of the central engine resides in highly relativistic material. These results predict large differences in the opening angles of outflows from binary neutron star mergers versus neutron star–black hole mergers.« less

Analyses of Magnetic Resonance Imaging of Cerebrospinal Fluid Dynamics Pre and Post Short and Long-Duration Space Flights

NASA Technical Reports Server (NTRS)

Alperin, Noam; Barr, Yael; Lee, Sang H.; Mason,Sara; Bagci, Ahmet M.

2015-01-01

Preliminary results are based on analyses of data from 17 crewmembers. The initial analysis compares pre to post-flight changes in total cerebral blood flow (CBF) and craniospinal CSF flow volume. Total CBF is obtained by summation of the mean flow rates through the 4 blood vessels supplying the brain (right and left internal carotid and vertebral arteries). Volumetric flow rates were obtained using an automated lumen segmentation technique shown to have 3-4-fold improved reproducibility and accuracy over manual lumen segmentation (6). Two cohorts, 5 short-duration and 8 long-duration crewmembers, who were scanned within 3 to 8 days post landing were included (4 short-duration crewmembers with MRI scans occurring beyond 10 days post flight were excluded). The VIIP Clinical Practice Guideline (CPG) classification is being used initially as a measure for VIIP syndrome severity. Median CPG scores of the short and long-duration cohorts were similar, 2. Mean preflight total CBF for the short and long-duration cohorts were similar, 863+/-144 and 747+/-119 mL/min, respectively. Percentage CBF changes for all short duration crewmembers were 11% or lower, within the range of normal physiological fluctuations in healthy individuals. In contrast, in 4 of the 8 long-duration crewmembers, the change in CBF exceeded the range of normal physiological fluctuation. In 3 of the 4 subjects an increase in CBF was measured. Large pre to post-flight changes in the craniospinal CSF flow volume were found in 6 of the 8 long-duration crewmembers. Box-Whisker plots of the CPG and the percent CBF and CSF flow changes for the two cohorts are shown in Figure 4. Examples of CSF flow waveforms for a short and two long-duration (CPG 0 and 3) are shown in Figure 5. Changes in CBF and CSF flow dynamics larger than normal physiological fluctuations were observed in the long-duration crewmembers. Changes in CSF flow were more pronounced than changes in CBF. Decreased CSF flow dynamics were observed

Identification of traffic control devices for mobile and short duration work operations

DOT National Transportation Integrated Search

2006-07-01

This report documents and summarizes the study Identification of Traffic Control Devices for Mobile and Short Duration Work Operations, for the New Jersey Department of Transportation. The study was conducted in three tasks: 1. Literature Searc...

Impact of bottled water storage duration and location on bacteriological quality.

PubMed

Duranceau, Steven J; Emerson, Hilary P; Wilder, Rebecca J

2012-01-01

An investigation studying the effects of storage duration and location on the persistence of heterotrophic microorganisms in oligotrophic bottled water environments has been completed. One-gallon high-density polyethylene water containers stored for up to 16 weeks at temperatures ranging from 2°C to >49°C in a refrigerator, indoor cabinet, covered porch, and car trunk were evaluated for microbiological quality. Heterotrophic plate counts (HPCs) of up to 4 × 10(3) cfu/mL were detected in containers stored on a porch and car trunk; whereas, HPCs were found not to exceed 400 cfu/mL and 100 cfu/mL for bottles stored in indoor cabinets and refrigerators, respectively. Containers stored on an enclosed porch for up to seven years contained HPC of up to 4 × 10(4) cfu/mL. Logistic and Gompertz growth models predicted microbial growth rates for bottled water stored on a protected porch environment for long (R(2) 0.99) and short-term (R(2) 0.86) durations.

A model for plasma volume changes during short duration spaceflight

NASA Technical Reports Server (NTRS)

Davis, John E.

1989-01-01

It is well established that plasma volume decreases during spaceflight and simulated weightlessness (bedrest). The decrement in plasma volume is thought to contribute to the orthostatic intolerance that has been observed in some crew members following spaceflight. To date, no studies have evaluated the effectiveness of fluid countermeasures of varying osmolality in the restoration of plasma volume and orthostatic tolerance in a controlled study. The overall objectives of this project were to: (1) provide a model that would rapidly and safely produce a fluid loss comparable to that which occurs during short duration spaceflight; and (2) design a study that would determine the optimal drink solution to restore orthostatic tolerance and describe the mechanism(s) whereby orthostatic tolerance is restored. In summary, Lasix can be used as a way of simulating the plasma volume changes that occur during short duration spaceflight. The total loss of plasma is comparable to spaceflight. Lasix is fast acting, and has relatively few side effects. The present design for evaluating the optimal fluid countermeasures will have important implications in restoring orthostatic tolerance and function in the latter stages of spaceflight when it is essential for safe operation of the spacecraft.

Sleep Quality, Sleep Duration, and the Risk of Coronary Heart Disease: A Prospective Cohort Study With 60,586 Adults.

PubMed

Lao, Xiang Qian; Liu, Xudong; Deng, Han-Bing; Chan, Ta-Chien; Ho, Kin Fai; Wang, Feng; Vermeulen, Roel; Tam, Tony; Wong, Martin C S; Tse, L A; Chang, Ly-Yun; Yeoh, Eng-Kiong

2018-01-15

There is limited information on the relationship between risk of cardiovascular disease and the joint effects of sleep quality and sleep duration, especially from large, prospective, cohort studies. This study is to prospectively investigate the joint effects of sleep quality and sleep duration on the development of coronary heart disease. This study examined 60,586 adults aged 40 years or older. A self-administered questionnaire was used to collect information on sleep quality and sleep duration as well as a wide range of potential confounders. Events of coronary heart disease were self-reported in subsequent medical examinations. Two types of Sleep Score (multiplicative and additive) were constructed to reflect the participants' sleep profiles, considering both sleep quality and sleep duration. The Cox regression model was used to estimate the hazard ratio (HR) and the 95% confidence interval (CI). A total of 2,740 participants (4.5%) reported new events of coronary heart disease at follow-up. For sleep duration, participants in the group of < 6 h/d was significantly associated with an increased risk of coronary heart disease (HR: 1.13, 95% CI: 1.04-1.23). However, the association in the participants with long sleep duration (> 8 h/d) did not reach statistical significance (HR: 1.11, 95% CI: 0.98-1.26). For sleep quality, both dreamy sleep (HR: 1.21, 95% CI: 1.10-1.32) and difficult to fall asleep/use of sleeping pills or drugs (HR: 1.40, 95% CI: 1.25-1.56) were associated with an increased risk of the disease. Participants in the lowest quartile of multiplicative Sleep Score (HR: 1.31, 95% CI: 1.16-1.47) and of additive sleep score (HR: 1.31, 95% CI: 1.16-1.47) were associated with increased risk of coronary heart disease compared with those in the highest quartile. Both short sleep duration and poor sleep quality are associated with the risk of coronary heart disease. The association for long sleep duration does not reach statistical significance. Lower Sleep

A simple analytical infiltration model for short-duration rainfall

NASA Astrophysics Data System (ADS)

Wang, Kaiwen; Yang, Xiaohua; Liu, Xiaomang; Liu, Changming

2017-12-01

Many infiltration models have been proposed to simulate infiltration process. Different initial soil conditions and non-uniform initial water content can lead to infiltration simulation errors, especially for short-duration rainfall (SHR). Few infiltration models are specifically derived to eliminate the errors caused by the complex initial soil conditions. We present a simple analytical infiltration model for SHR infiltration simulation, i.e., Short-duration Infiltration Process model (SHIP model). The infiltration simulated by 5 models (i.e., SHIP (high) model, SHIP (middle) model, SHIP (low) model, Philip model and Parlange model) were compared based on numerical experiments and soil column experiments. In numerical experiments, SHIP (middle) and Parlange models had robust solutions for SHR infiltration simulation of 12 typical soils under different initial soil conditions. The absolute values of percent bias were less than 12% and the values of Nash and Sutcliffe efficiency were greater than 0.83. Additionally, in soil column experiments, infiltration rate fluctuated in a range because of non-uniform initial water content. SHIP (high) and SHIP (low) models can simulate an infiltration range, which successfully covered the fluctuation range of the observed infiltration rate. According to the robustness of solutions and the coverage of fluctuation range of infiltration rate, SHIP model can be integrated into hydrologic models to simulate SHR infiltration process and benefit the flood forecast.

Changes in Near Visual Acuity of Over Time in the Astronaut Corps

NASA Technical Reports Server (NTRS)

Taiym, Wafa; Wear, Mary L.; Locke, James; Mason, Sara; VanBaalen, Mary

2014-01-01

We hypothesized that visual impairment due to intracranial pressure (VIIP) would increase the rate of which presbyopia would occur in the astronaut population, with long durations flyers at an especially high risk. Presbyopia is characterized as the gradual loss of near visual acuity overtime due to a loss in ability to accommodate. It generally develops in the mid-40s and progresses until about age 65. This analysis considered annual vision exams conducted on active NASA astronauts with spaceflight experience currently between the ages of 40 to 60 years of age. Onset of presbyopia was characterized as a shift of at least 20 units on the standard Snellen test from one annual exam to the next. There were 236 short duration and 48 long duration flyers, the majority of whom did experience onset of presbyopia between age 40 and 60. This shift however, did not necessarily come after spaceflight. In comparing the short and long duration flyers the mean age of onset was 47 years old (SD+/-3.7). The mean of onset within the general population is 45 to 47 years old [1, 2]. The mean age of the onset of presbyopia as compared to the general population indicates that space flight does not induce early development of presbyopia.

Sleep quality and duration are associated with performance in maximal incremental test.

PubMed

Antunes, B M; Campos, E Z; Parmezzani, S S; Santos, R V; Franchini, E; Lira, F S

2017-08-01

Inadequate sleep patterns may be considered a trigger to development of several metabolic diseases. Additionally, sleep deprivation and poor sleep quality can negatively impact performance in exercise training. However, the impact of sleep duration and sleep quality on performance during incremental maximal test performed by healthy men is unclear. Therefore, the purpose of the study was to analyze the association between sleep pattern (duration and quality) and performance during maximal incremental test in healthy male individuals. A total of 28 healthy males volunteered to take part in the study. Sleep quality, sleep duration and physical activity were subjectively assessed by questionnaires. Sleep pattern was classified by sleep duration (>7h or <7h of sleep per night) and sleep quality according to the sum of measured points and/or scores by the Pittsburgh Sleep Quality Index (PSQI). Incremental exercise test was performed at 35 watts for untrained subjects, 70 watts for physically active subjects and 105 watts for well-trained subjects. HR max was correlated with sleep quality (r=0.411, p=0.030) and sleep duration (r=-0.430, p=0.022). Participants reporting good sleep quality presented higher values of W max , VO 2max and lower values of HR max when compared to participants with altered sleep. Regarding sleep duration, only W max was influenced by the amount of sleeping hours per night and this association remained significant even after adjustment by VO 2max . Sleep duration and quality are associated, at least in part, with performance during maximal incremental test among healthy men, with losses in W max and HR max . In addition, our results suggest that the relationship between sleep patterns and performance, mainly in W max , is independent of fitness condition. Copyright © 2017 Elsevier Inc. All rights reserved.

The Consumption of Dietary Antioxidant Vitamins Modifies the Risk of Obesity among Korean Men with Short Sleep Duration

PubMed Central

2017-01-01

Short sleep duration has been reported to be associated with various health problems. This study examined the influence of sleep duration on the odds of being obese in relation to the consumption of dietary antioxidant vitamins among 3941 Korean men between 40 and 69 years of age. After adjusting for age, education, household income, marital status, insomnia, smoking and drinking status, participants with short sleep duration (<6 h) had significantly higher body mass index (p = 0.005), body fat mass (p = 0.010), body fat percentage (p = 0.021), waist circumference (p = 0.029), as well as the odds ratio (OR) of risk of obesity [OR (95% CI) = 1.467 (1.282–1.678)], compared to participants with optimal sleep duration (≥7 h). Short sleepers with a low consumption of dietary antioxidant vitamins had a higher risk of obesity than those with a high consumption of dietary antioxidant vitamins; however, this relationship did not hold among those with optimal sleep duration. Although a causal relationship among sleep-related variables could not be definitively demonstrated because of this study’s cross-sectional design, our results suggested that the increased risk of obesity associated with short sleep duration may be modified by the consumption of dietary antioxidant vitamins. PMID:28726758

Laser-launched flyer plate and confined laser ablation for shock wave loading: validation and applications.

PubMed

Paisley, Dennis L; Luo, Sheng-Nian; Greenfield, Scott R; Koskelo, Aaron C

2008-02-01

We present validation and some applications of two laser-driven shock wave loading techniques: laser-launched flyer plate and confined laser ablation. We characterize the flyer plate during flight and the dynamically loaded target with temporally and spatially resolved diagnostics. With transient imaging displacement interferometry, we demonstrate that the planarity (bow and tilt) of the loading induced by a spatially shaped laser pulse is within 2-7 mrad (with an average of 4+/-1 mrad), similar to that in conventional techniques including gas gun loading. Plasma heating of target is negligible, in particular, when a plasma shield is adopted. For flyer plate loading, supported shock waves can be achieved. Temporal shaping of the drive pulse in confined laser ablation allows for flexible loading, e.g., quasi-isentropic, Taylor-wave, and off-Hugoniot loading. These techniques can be utilized to investigate such dynamic responses of materials as Hugoniot elastic limit, plasticity, spall, shock roughness, equation of state, phase transition, and metallurgical characteristics of shock-recovered samples.

Immune changes during short-duration missions

NASA Technical Reports Server (NTRS)

Taylor, G. R.

1993-01-01

Spaceflight materially influences the immune mechanism of humans and animals. Effects resulting from missions of less than 1 month are examined. Effects from longer missions are discussed in the companion paper by Konstantinova et al. Most immunology studies have involved analyses of subjects and samples from subjects obtained after flight, with the data being compared with similar data obtained before flight. These studies have demonstrated that short-duration missions can result in a postflight depression in blast cell transformation, major changes in cytokine function, and alterations in the relative numbers of immune cell populations. In addition to these post- vs. preflight studies, some data have been produced in flight. However, these in vitro analyses have been less than satisfactory because of differences between in-flight and ground-control conditions. Recently, both the U.S. and Russian space programs have started collecting in-flight, in vivo, cell-mediated immunity data. These studies have confirmed that the human cell-mediated immune system is blunted during spaceflight.

Immune changes during short-duration missions.

PubMed

Taylor, G R

1993-09-01

Spaceflight materially influences the immune mechanism of humans and animals. Effects resulting from missions of less than 1 month are examined. Effects from longer missions are discussed in the companion paper by Konstantinova et al. Most immunology studies have involved analyses of subjects and samples from subjects obtained after flight, with the data being compared with similar data obtained before flight. These studies have demonstrated that short-duration missions can result in a postflight depression in blast cell transformation, major changes in cytokine function, and alterations in the relative numbers of immune cell populations. In addition to these post- vs. preflight studies, some data have been produced in flight. However, these in vitro analyses have been less than satisfactory because of differences between in-flight and ground-control conditions. Recently, both the U.S. and Russian space programs have started collecting in-flight, in vivo, cell-mediated immunity data. These studies have confirmed that the human cell-mediated immune system is blunted during spaceflight.

Insomnia Patients With Objective Short Sleep Duration Have a Blunted Response to Cognitive Behavioral Therapy for Insomnia.

PubMed

Bathgate, Christina J; Edinger, Jack D; Krystal, Andrew D

2017-01-01

This study examined whether individuals with insomnia and objective short sleep duration <6 h, a subgroup with greater risks of adverse health outcomes, differ in their response to cognitive-behavioral therapy for insomnia (CBT-I) when compared to individuals with insomnia and normal sleep duration ≥6 h. Secondary analyses of a randomized, clinical trial with 60 adult participants (n = 31 women) from a single academic medical center. Outpatient treatment lasted 8 weeks, with a final follow-up conducted at 6 months. Mixed-effects models controlling for age, sex, CBT-I treatment group assignment, and treatment provider examined sleep parameters gathered via actigraphy, sleep diaries, and an Insomnia Symptom Questionnaire (ISQ) across the treatment and follow-up period. Six months post-CBT-I treatment, individuals with insomnia and normal sleep duration ≥6 h fared significantly better on clinical improvement milestones than did those with insomnia and short sleep duration <6 h. Specifically, individuals with insomnia and normal sleep duration had significantly higher insomnia remission (ISQ < 36.5; χ2[1, N = 60] = 44.72, p < .0001), more normative sleep efficiency (SE) on actigraphy (SE > 80%; χ2[1, N = 60] = 21, p < .0001), normal levels of middle of the night wake after sleep onset (MWASO) <31 minutes (χ2[1, N = 60] = 37.85, p < .0001), and a >50% decline in MWASO (χ2[1, N = 60] = 60, p < .0001) compared to individuals with insomnia and short sleep duration. Additionally, those with insomnia and normal sleep duration had more success decreasing their total wake time (TWT) at the 6-month follow-up compared to those with insomnia and short sleep duration (χ2[2, N = 60] = 44.1, p < .0001). Receiver-operating characteristic curve analysis found that using a 6-h cutoff with actigraphy provided a 95.7% sensitivity and 91.9% specificity for determining insomnia remission, with the area under the curve = 0.986. Findings suggest that individuals with insomnia and

Short Operative Duration and Surgical Site Infection Risk in Hip and Knee Arthroplasty Procedures

PubMed Central

Dicks, Kristen V.; Baker, Arthur W.; Durkin, Michael J.; Anderson, Deverick J.; Moehring, Rebekah W.; Chen, Luke F.; Sexton, Daniel J.; Weber, David J.; Lewis, Sarah S.

2016-01-01

OBJECTIVE To determine the association (1) between shorter operative duration and surgical site infection (SSI) and (2) between surgeon median operative duration and SSI risk among first-time hip and knee arthroplasties. DESIGN Retrospective cohort study SETTING A total of 43 community hospitals located in the southeastern United States. PATIENTS Adults who developed SSIs according to National Healthcare Safety Network criteria within 365 days of first-time knee or hip arthroplasties performed between January 1, 2008 and December 31, 2012. METHODS Log-binomial regression models estimated the association (1) between operative duration and SSI outcome and (2) between surgeon median operative duration and SSI outcome. Hip and knee arthroplasties were evaluated in separate models. Each model was adjusted for American Society of Anesthesiology score and patient age. RESULTS A total of 25,531 hip arthroplasties and 42,187 knee arthroplasties were included in the study. The risk of SSI in knee arthroplasties with an operative duration shorter than the 25th percentile was 0.40 times the risk of SSI in knee arthroplasties with an operative duration between the 25th and 75th percentile (risk ratio [RR], 0.40; 95% confidence interval [CI], 0.38–0.56; P <.01). Short operative duration did not demonstrate significant association with SSI for hip arthroplasties (RR, 1.04; 95% CI, 0.79–1.37; P =.36). Knee arthroplasty surgeons with shorter median operative durations had a lower risk of SSI than surgeons with typical median operative durations (RR, 0.52; 95% CI, 0.43–0.64; P <.01). CONCLUSIONS Short operative durations were not associated with a higher SSI risk for knee or hip arthroplasty procedures in our analysis. PMID:26391277

Treatment response and tolerability of frovatriptan in patients reporting short- or long-duration migraines at baseline.

PubMed

Kelman, Leslie; Harper, Samira Q; Hu, Xiaojun; Campbell, John C

2010-09-01

Compare migraine duration with frovatriptan (versus baseline) in migraineurs reporting long- (24-72 h) or short-duration (<24 h) migraines at baseline. Post hoc analysis of two postmarketing surveillance studies of migraineurs in German primary care clinics using frovatriptan (2.5 mg) to treat a single migraine attack. Using case-report forms, physicians recorded migraine characteristics at baseline (aura, duration, frequency, severity) and with frovatriptan (duration, severity, and recurrence). Patients and physicians rated frovatriptan effectiveness and tolerability versus previous therapy; physicians recorded adverse reactions. The primary analysis was change in migraine duration with frovatriptan versus baseline. At baseline, 44.2% (7178/16 253) and 55.8% (9075/16 253) of patients reported short- and long-duration migraines, respectively; long-duration migraines were more often frequent (> or =3/months; 55.5% [4893/8811] vs. 30.6% [2132/6973]; p < 0.001; 95% CI, 23.5-26.5%), severe (61.7% [5584/9047] vs. 33.9% [2427/7156]; p < 0.001; 95% CI, 26.3-29.3%), and accompanied by aura (46.8% [4199/8977] vs. 31.3% [2215/7088]; p < 0.001; 95% CI, 14.0-17.0%). Mean (SD) onset of frovatriptan effect was <1 h; 72.3% (11 592/16 040) of patients required only one frovatriptan tablet. With frovatriptan, patients were 26.8-fold more likely to experience decreased versus increased headache duration (p < 0.001; 95% CI, 23.5-30.2) and 76.5% of patients reporting long-duration migraines at baseline experienced short-duration migraines. Most patients (87-90%) and physicians (70-75%) rated frovatriptan more effective and tolerable than previous therapies. Patients with more severe migraine characteristics at baseline were more likely to have attacks lasting > or =24 h. When using frovatriptan, patients were 26.8-fold more likely to experience decreased versus increased headache duration. Frovatriptan might be a good option for patients with long-duration or recurrent migraine

Contribution of marital conflict to marital quality in short and long-term marriages: An actor-partner interdependence model

PubMed Central

Ahmadi, Khodabakhsh; Rezazade, Majid; Saadat, Hassan; Kimiaei, Seyed Ali; Zade, Nima Hoseyn

2015-01-01

Aims: In the field of family research, previous studies have made great strides toward understanding the relationship between marital conflict and quality. However, they have only studied couples in short-term marriages. Therefore, much remains to be unraveled with regard to long-term marriages. We aimed investigate the comparative contribution of aspects of marital conflict to marital quality in short-and long-term marriages in Iranian families. Materials and Methods: Using random clustered sampling, 400 dyads in intact first marriages were surveyed across eight provinces of Iran. Complete surveys for both husbands and wives were returned for 162 households (couple's response rate: 40.5%). Survey measures included demographics questionnaire, Barati and Sanai's Marital Conflict Questionnaire and Blum and Mehrabian's Comprehensive Marital Satisfaction Scale. Structural equation modeling was used to test the actor-partner interdependence model of marital conflict-marital quality. Results: Generalized additive models were incorporated to define what constitutes short-and long-term marriages. Based on the models regressed, duration ≤ 10 years was defined as short-term, whereas duration ≥ 25 years was labeled long-term. In short-term marriages (n = 44), decreased sexual relations, increased daily hassles and sidedness in relations with parents were negatively associated with marital quality in both actor and actor-to-partner paths. In long-term married couples (n = 46), only increased daily hassles (P < 0.001) and disagreement over financial affairs (P = 0.005) contributed to actor paths and only sidedness in relationships with parents showed significant negative association to marital quality in actor-to-partner paths. Conclusions: Different themes of conflict contribute to the diminished level of marital quality in early and late stages of the marriage. Conflicts over sex, relationship with extended family and daily hassles are emphasized in the early years of

Understanding the role of sleep quality and sleep duration in commercial driving safety.

PubMed

Lemke, Michael K; Apostolopoulos, Yorghos; Hege, Adam; Sönmez, Sevil; Wideman, Laurie

2016-12-01

Long-haul truck drivers in the United States suffer disproportionately high injury rates. Sleep is a critical factor in these outcomes, contributing to fatigue and degrading multiple aspects of safety-relevant performance. Both sleep duration and sleep quality are often compromised among truck drivers; however, much of the efforts to combat fatigue focus on sleep duration rather than sleep quality. Thus, the current study has two objectives: (1) to determine the degree to which sleep impacts safety-relevant performance among long-haul truck drivers; and (2) to evaluate workday and non-workday sleep quality and duration as predictors of drivers' safety-relevant performance. A non-experimental, descriptive, cross-sectional design was employed to collect survey and biometric data from 260 long-haul truck drivers. The Trucker Sleep Disorders Survey was developed to assess sleep duration and quality, the impact of sleep on job performance and accident risk, and other relevant work organization characteristics. Descriptive statistics assessed work organization variables, sleep duration and quality, and frequency of engaging in safety-relevant performance while sleepy. Linear regression analyses were conducted to evaluate relationships between sleep duration, sleep quality, and work organization variables with safety composite variables. Drivers reported long work hours, with over 70% of drivers working more than 11h daily. Drivers also reported a large number of miles driven per week, with an average of 2,812.61 miles per week, and frequent violations of hours-of-service rules, with 43.8% of drivers "sometimes to always" violating the "14-h rule." Sleep duration was longer, and sleep quality was better, on non-workdays compared on workdays. Drivers frequently operated motor vehicles while sleepy, and sleepiness impacted several aspects of safety-relevant performance. Sleep quality was better associated with driving while sleepy and with job performance and concentration

Steady-state pattern electroretinogram and short-duration transient visual evoked potentials in glaucomatous and healthy eyes.

PubMed

Amarasekera, Dilru C; Resende, Arthur F; Waisbourd, Michael; Puri, Sanjeev; Moster, Marlene R; Hark, Lisa A; Katz, L Jay; Fudemberg, Scott J; Mantravadi, Anand V

2018-01-01

This study evaluates two rapid electrophysiological glaucoma diagnostic tests that may add a functional perspective to glaucoma diagnosis. This study aimed to determine the ability of two office-based electrophysiological diagnostic tests, steady-state pattern electroretinogram and short-duration transient visual evoked potentials, to discern between glaucomatous and healthy eyes. This is a cross-sectional study in a hospital setting. Forty-one patients with glaucoma and 41 healthy volunteers participated in the study. Steady-state pattern electroretinogram and short-duration transient visual evoked potential testing was conducted in glaucomatous and healthy eyes. A 64-bar-size stimulus with both a low-contrast and high-contrast setting was used to compare steady-state pattern electroretinogram parameters in both groups. A low-contrast and high-contrast checkerboard stimulus was used to measure short-duration transient visual evoked potential parameters in both groups. Steady-state pattern electroretinogram parameters compared were MagnitudeD, MagnitudeD/Magnitude ratio, and the signal-to-noise ratio. Short-duration transient visual evoked potential parameters compared were amplitude and latency. MagnitudeD was significantly lower in glaucoma patients when using a low-contrast (P = 0.001) and high-contrast (P < 0.001) 64-bar-size steady-state pattern electroretinogram stimulus. MagnitudeD/Magnitude ratio and SNR were significantly lower in the glaucoma group when using a high-contrast 64-bar-size stimulus (P < 0.001 and P = 0.010, respectively). Short-duration transient visual evoked potential amplitude and latency were not significantly different between the two groups. Steady-state pattern electroretinogram was effectively able to discern between glaucomatous and healthy eyes. Steady-state pattern electroretinogram may thus have a role as a clinically useful electrophysiological diagnostic tool. © 2017 Royal Australian and New Zealand College of

International collaboration on Russian spacecraft and the case for free flyer biosatellites

NASA Technical Reports Server (NTRS)

Grindeland, Richard E.; Ilyin, Eugene A.; Holley, Daniel C.; Skidmore, Michael G.

2005-01-01

flight-related technology, some of which also has application on our planet. In summary, the Cosmos biosatellite flights were extremely productive and of low cost. The Bion vehicles are versatile in that they can be placed into a variety of orbits and altitudes, and can carry radiation sources or other hazardous material which cannot be carried on manned vehicles. With recent advances in sensor, robotic, and data processing technology, future free flyers will be even more productive, and will largely preclude the need to fly animal experiments on manned vehicles. Currently, mammalian researchers do not have access to space for an unknown time, seriously impeding the advancement and understanding of space physiology during long duration missions. Initiation of a new, international program of free flyer biosatellites is critical to our further understanding of space physiology, and essential to continued human exploration of space.

Lessons learned from the Space Flyer Unit (SFU) mission.

PubMed

Kuriki, Kyoichi; Ninomiya, Keiken; Takei, Mitsuru; Matsuoka, Shinobu

2002-11-01

The Space Flyer Unit (SFU) system and mission chronology are briefly introduced. Lessons learned from the SFU mission are categorized as programmatic and engineering lessons. In the programmatic category are dealt with both international and domestic collaborations. As for the engineering lessons safety design, orbital operation, in-flight anomaly, and post flight analyses are the major topics reviewed. c2002 Elsevier Science Ltd. All rights reserved.

Rather than resonance, flapping wing flyers may play on aerodynamics to improve performance.

PubMed

Ramananarivo, Sophie; Godoy-Diana, Ramiro; Thiria, Benjamin

2011-04-12

Saving energy and enhancing performance are secular preoccupations shared by both nature and human beings. In animal locomotion, flapping flyers or swimmers rely on the flexibility of their wings or body to passively increase their efficiency using an appropriate cycle of storing and releasing elastic energy. Despite the convergence of many observations pointing out this feature, the underlying mechanisms explaining how the elastic nature of the wings is related to propulsive efficiency remain unclear. Here we use an experiment with a self-propelled simplified insect model allowing to show how wing compliance governs the performance of flapping flyers. Reducing the description of the flapping wing to a forced oscillator model, we pinpoint different nonlinear effects that can account for the observed behavior--in particular a set of cubic nonlinearities coming from the clamped-free beam equation used to model the wing and a quadratic damping term representing the fluid drag associated to the fast flapping motion. In contrast to what has been repeatedly suggested in the literature, we show that flapping flyers optimize their performance not by especially looking for resonance to achieve larger flapping amplitudes with less effort, but by tuning the temporal evolution of the wing shape (i.e., the phase dynamics in the oscillator model) to optimize the aerodynamics.

Rather than resonance, flapping wing flyers may play on aerodynamics to improve performance

PubMed Central

Ramananarivo, Sophie; Godoy-Diana, Ramiro; Thiria, Benjamin

2011-01-01

Saving energy and enhancing performance are secular preoccupations shared by both nature and human beings. In animal locomotion, flapping flyers or swimmers rely on the flexibility of their wings or body to passively increase their efficiency using an appropriate cycle of storing and releasing elastic energy. Despite the convergence of many observations pointing out this feature, the underlying mechanisms explaining how the elastic nature of the wings is related to propulsive efficiency remain unclear. Here we use an experiment with a self-propelled simplified insect model allowing to show how wing compliance governs the performance of flapping flyers. Reducing the description of the flapping wing to a forced oscillator model, we pinpoint different nonlinear effects that can account for the observed behavior—in particular a set of cubic nonlinearities coming from the clamped-free beam equation used to model the wing and a quadratic damping term representing the fluid drag associated to the fast flapping motion. In contrast to what has been repeatedly suggested in the literature, we show that flapping flyers optimize their performance not by especially looking for resonance to achieve larger flapping amplitudes with less effort, but by tuning the temporal evolution of the wing shape (i.e., the phase dynamics in the oscillator model) to optimize the aerodynamics. PMID:21444774

Metabolic syndrome and sleep duration in police officers.

PubMed

McCanlies, Erin C; Slaven, James E; Smith, Lindsay M; Andrew, Michael E; Charles, Luenda E; Burchfiel, Cecil M; Violanti, John M

2012-01-01

To examine associations for sleep quality and quantity with metabolic syndrome (MS) and its five components in police officers. The study population consisted of 98 randomly selected officers (39 women and 59 men) for whom MS and sleep data were available. Sleep duration (categorized as short < 6 hours, long ≥ 6 hours) for the past week and quality of sleep were collected by interviewer-administered questionnaires. MS was assessed using standard criteria. Generalized linear models were used to assess associations between sleep duration or sleep quality and MS, and the mean number of MS components. Metabolic syndrome was present in 22.0% and 2.6% of the male and female officers, respectively. Women with short sleep had a significantly higher mean number of MS components (mean=1.43) than those with longer sleep (mean=0.81, p=0.0316). Officers who stopped breathing during the night had more MS components (mean=2.43) compared to those who did not (mean =1.13, p=0.0206). Sleep duration and quality were associated with the mean number of MS components, particularly in women. Future research should examine these associations prospectively, in a larger cohort, exploring possible gender differences.

Sleep Quality, Sleep Duration, and the Risk of Coronary Heart Disease: A Prospective Cohort Study With 60,586 Adults

PubMed Central

Lao, Xiang Qian; Liu, Xudong; Deng, Han-Bing; Chan, Ta-Chien; Ho, Kin Fai; Wang, Feng; Vermeulen, Roel; Tam, Tony; Wong, Martin C.S.; Tse, L.A.; Chang, Ly-yun; Yeoh, Eng-Kiong

2018-01-01

Study Objectives: There is limited information on the relationship between risk of cardiovascular disease and the joint effects of sleep quality and sleep duration, especially from large, prospective, cohort studies. This study is to prospectively investigate the joint effects of sleep quality and sleep duration on the development of coronary heart disease. Methods: This study examined 60,586 adults aged 40 years or older. A self-administered questionnaire was used to collect information on sleep quality and sleep duration as well as a wide range of potential confounders. Events of coronary heart disease were self-reported in subsequent medical examinations. Two types of Sleep Score (multiplicative and additive) were constructed to reflect the participants' sleep profiles, considering both sleep quality and sleep duration. The Cox regression model was used to estimate the hazard ratio (HR) and the 95% confidence interval (CI). Results: A total of 2,740 participants (4.5%) reported new events of coronary heart disease at follow-up. For sleep duration, participants in the group of < 6 h/d was significantly associated with an increased risk of coronary heart disease (HR: 1.13, 95% CI: 1.04–1.23). However, the association in the participants with long sleep duration (> 8 h/d) did not reach statistical significance (HR: 1.11, 95% CI: 0.98–1.26). For sleep quality, both dreamy sleep (HR: 1.21, 95% CI: 1.10–1.32) and difficult to fall asleep/use of sleeping pills or drugs (HR: 1.40, 95% CI: 1.25–1.56) were associated with an increased risk of the disease. Participants in the lowest quartile of multiplicative Sleep Score (HR: 1.31, 95% CI: 1.16–1.47) and of additive sleep score (HR: 1.31, 95% CI: 1.16–1.47) were associated with increased risk of coronary heart disease compared with those in the highest quartile. Conclusions: Both short sleep duration and poor sleep quality are associated with the risk of coronary heart disease. The association for long sleep

Comparison of Postural Recovery Following Short and Long Duration Spaceflights

NASA Technical Reports Server (NTRS)

Wood, S. J.; Fiedler, J.; Taylor, L. C.; Kozlovskaya, I.; Black, F. O.; Paloski, W. H.

2010-01-01

INTRODUCTION: Post-flight postural ataxia reflects adaptive changes to vestibulo-spinal reflexes and control strategies adopted for movement in weightlessness. Quantitative measures obtained during computerized dynamic posturography (CDP) from US and Russian programs provide insight into the effect of spaceflight duration in terms of both the initial decrements and recovery of postural stability. METHODS: CDP was obtained on 117 crewmembers following Shuttle flights lasting 4-17 days, and on 64 crewmembers following long-duration missions lasting 48-380 days. Although the number and timing of sessions varied, the goal was to characterize postural recovery pooling similar measures from different research and flight medicine programs. This report focuses on eyes closed, head erect conditions with either a fixed or sway-referenced base of support. A smaller subset of subjects repeated the sway-referenced condition while making pitch head movements (+/- 20deg at 0.33Hz). Equilibrium scores were derived from peak-to-peak anterior-posterior sway. Fall probability was modeled using Bayesian statistical methods to estimate parameters of a logit function. RESULTS: The standard Romberg condition was the least sensitive. Longer duration flights led to larger decrements in stability with sway-reference support during the first 1-2 days, although the timecourse of recovery was similar across flight duration with head erect. Head movements led to increased incidence of falls during the first week, with a significantly longer recovery following long duration flights. CONCLUSIONS: The diagnostic assessment of postural instability, and differences in the timecourse of postural recovery between short and long flight durations, are more pronounced during unstable support conditions requiring active head movements.

Immune Dysregulation Following Short versus Long Duration Space Flight. Version 03

NASA Technical Reports Server (NTRS)

Crucian, Brian E.; Stowe, Raymond P.; Pierson, Duane L.; Sams, Clarence F.

2007-01-01

Immune system dysregulation has been demonstrated to occur during spaceflight and has the potential to cause serious health risks to crewmembers participating in exploration-class missions. A comprehensive immune assessment was recently performed on 13 short duration Space Shuttle crewmembers and 8 long duration International Space Station (ISS) crewmembers. Statistically significant post-flight phenotype alterations (as compared to pre-flight baseline) for the Shuttle crewmembers included: granulocytosis, increased percentage of B cells, reduced percentage of NK cells, elevated CD4/CD8 ratio, elevated levels of memory CD4+ T cells, and a CD8+ T cell shift to a less differentiated state. For the Shuttle crewmembers, T cell function was surprisingly elevated post-flight, among both the CD4+ and CD8+ subsets. This is likely an acute stress response in less-deconditioned crewmembers. The percentage of CD4+/IL-2+, CD4+/IFNg+ and CD8+/IFNg+ T cells were all decreased at landing. Culture secreted IFNg production was significantly decreased at landing, whereas production of Th2 cytokines was largely unchanged. It was found that the IFNg:IL-10 ratio was obviously declined in the Shuttle crewmembers immediately post-flight. A similar pattern of alterations were observed for the long duration ISS crewmembers. In contrast to Shuttle crewmembers, the ISS crewmembers demonstrated a dramatic reduction in T cell function immediately post-flight. This may be related to the effect of acute landing stress in conjunction with prolonged deconditioning associated with extended flight. The reduction in IFNg:IL-10 ratio (Th2 shift) was also observed post-flight in the ISS crewmembers to a much higher degree. These data indicate consistent peripheral phenotype changes and altered cytokine production profiles occur following space travel of both short and long duration.

Qualities of online friendships with different gender compositions and durations.

PubMed

Cheng, Grand H L; Chan, Darius K S; Tong, Po Yee

2006-02-01

This study was designed to examine the qualities of online friendships with different gender compositions that had been maintained for varying periods of time. A total of 167 Hong Kong Internet-users rated the qualities of their same-sex and cross-sex online friendships on measures such as intimacy, trust, self-disclosure, and relational satisfaction. A 2 (gender of respondents: male vs. female) x 2 (gender of online friends: same-sex vs. opposite-sex) x 3 (duration of friendships: less than 1 year vs. 1-2 years vs. more than 2 years) factorial design was adopted. MANOVA results reveal the three-way interaction effect on intimacy, trust, and relational satisfaction. Specifically, the qualities of male-female, female-male, and female-female online friendships were generally higher for those with a longer duration than those at the early stage of friendship development. However, the qualities of male-male friendships that had been maintained for more than 2 years were lower than those maintained for 2 years or less. These findings suggest that qualities of online friendships are subject to effects of gender composition and duration. The conceptual implications of these results are discussed.

Westward migration of tropical cyclone rapid-intensification over the Northwestern Pacific during short duration El Niño.

PubMed

Guo, Yi-Peng; Tan, Zhe-Min

2018-04-17

The El Niño-Southern Oscillation (ENSO) can significantly affect the rapid intensification of tropical cyclones over the western North Pacific (WNP). However, ENSO events have various durations, which can lead to different atmospheric and oceanic conditions. Here we show that during short duration El Niño events, the WNP tropical cyclone rapid-intensification mean occurrence position migrates westward by ~8.0° longitude, which is caused by reduced vertical wind shear, increased mid-tropospheric humidity, and enhanced tropical cyclone heat potential over the westernmost WNP. The changes in these factors are caused by westward advected upper ocean heat during the decaying phase of a short duration El Niño. As super El Niño events tend to have short durations and their frequency is projected to increase under global warming, our findings have important implications for future projections of WNP tropical cyclone activity.

A 'kilonova' associated with the short-duration γ-ray burst GRB 130603B.

PubMed

Tanvir, N R; Levan, A J; Fruchter, A S; Hjorth, J; Hounsell, R A; Wiersema, K; Tunnicliffe, R L

2013-08-29

Short-duration γ-ray bursts are intense flashes of cosmic γ-rays, lasting less than about two seconds, whose origin is unclear. The favoured hypothesis is that they are produced by a relativistic jet created by the merger of two compact stellar objects (specifically two neutron stars or a neutron star and a black hole). This is supported by indirect evidence such as the properties of their host galaxies, but unambiguous confirmation of the model is still lacking. Mergers of this kind are also expected to create significant quantities of neutron-rich radioactive species, whose decay should result in a faint transient, known as a 'kilonova', in the days following the burst. Indeed, it is speculated that this mechanism may be the predominant source of stable r-process elements in the Universe. Recent calculations suggest that much of the kilonova energy should appear in the near-infrared spectral range, because of the high optical opacity created by these heavy r-process elements. Here we report optical and near-infrared observations that provide strong evidence for such an event accompanying the short-duration γ-ray burst GRB 130603B. If this, the simplest interpretation of the data, is correct, then it confirms that compact-object mergers are the progenitors of short-duration γ-ray bursts and the sites of significant production of r-process elements. It also suggests that kilonovae offer an alternative, unbeamed electromagnetic signature of the most promising sources for direct detection of gravitational waves.

Short-duration transcutaneous electrical nerve stimulation in the postoperative period of cardiac surgery.

PubMed

Gregorini, Cristie; Cipriano Junior, Gerson; Aquino, Leticia Moraes de; Branco, João Nelson Rodrigues; Bernardelli, Graziella França

2010-03-01

Respiratory muscle strength has been related to the postoperative outcome of cardiac surgeries. The main documented therapeutic purpose of transcutaneous electrical nerve stimulation (TENS) is the reduction of pain, which could bring secondary benefits to the respiratory muscles and, consequently, to lung capacities and volumes. The objective of the present study was to evaluate the effectiveness of short-duration transcutaneous electrical nerve stimulation (TENS) in the reduction of pain and its possible influence on respiratory muscle strength and lung capacity and volumes of patients in the postoperative period of cardiac surgery. Twenty five patients with mean age of 59.9 +/- 10.3 years, of whom 72% were men, and homogeneous as regards weight and height, were randomly assigned to two groups. One group received therapeutic TENS (n = 13) and the other, placebo TENS (n = 12), for four hours on the third postoperative day of cardiac surgery. Pain was analyzed by means of a visual analogue scale, and of respiratory muscle strength as measured by maximum respiratory pressures and lung capacity and volumes before and after application of TENS. Short-duration TENS significantly reduced pain of patients in the postoperative period (p < 0.001). Respiratory muscle strength (p < 0.001), tidal volume (p < 0.001) and vital capacity (p < 0.05) significantly improved after therapeutic TENS, unlike in the placebo group. Short-duration TENS proved effective for the reduction of pain and improvement of respiratory muscle strength, as well as of lung volumes and capacity.

Evaluation of short-duration unscheduled absences among transit operators : TriMet case study

DOT National Transportation Integrated Search

2009-09-01

This report analyzes factors contributing to short duration (one to three days) unscheduled absences among operators : at TriMet, the transit provider for the Portland, Oregon metropolitan region. The analysis draws on a wide array of : operator-spec...

Evaluation of short-duration, unscheduled absences among transit operators: TriMet case study.

DOT National Transportation Integrated Search

2009-09-01

This report analyzes factors contributing to short duration (one to three days) unscheduled absences among operators at TriMet, the transit provider for the Portland, Oregon metropolitan region. The analysis draws on a wide array of operator-specific...

Management of Library Security. SPEC Kit 247 and SPEC Flyer 247.

ERIC Educational Resources Information Center

Soete, George J., Comp.; Zimmerman, Glen, Comp.

This SPEC (Systems and Procedures Exchange Center) Kit and Flyer reports results of a survey conducted in January 1999 that examined how ARL (Association of Research Libraries) member libraries assure the safety and security of persons, library materials, physical facilities, furnishings, computer equipment, etc. Forty-five of the 122 ARL member…

Associations between sleep disorders, sleep duration, quality of sleep, and hypertension: results from the National Health and Nutrition Examination Survey, 2005 to 2008.

PubMed

Bansil, Pooja; Kuklina, Elena V; Merritt, Robert K; Yoon, Paula W

2011-10-01

Sleep is a contributing factor to optimal health and vitality. However, to date, no national study has evaluated the simultaneous relationship between sleep disorders, quality, and duration with hypertension. Using data from National Health and Nutrition Examination Survey (NHANES) (2005 to 2008), hypertension was defined by current use of antihypertensive medication or systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg. Self-reported sleep disorders and duration were categorized from a single household interview question, and sleep quality was determined from several questions on sleeping habits. The prevalence of hypertension was 30.2% and 7.5%, and 33.0% and 52.1% reported having sleep disorders, short sleep, and poor sleep, respectively. After adjustment for demographic characteristics and comorbidities, having sleep disorders only was not significantly associated with hypertension (odds ratio [OR], 1.65; 95% confidence interval [CI], 0.73-3.77). However, this association was modified by sleep duration: significant associations were observed among adults with concurrent sleep disorders and short sleep (OR, 2.30; 95% CI, 1.49-3.56) and with sleep disorders, short sleep, and poor sleep (OR, 1.84; 95% CI, 1.13-2.98). These findings indicate an association between a combination of sleep problems and hypertension, but prospective studies are needed to understand the complex interplay between them. © 2011 Wiley Periodicals, Inc.

Looking at the heart of low and high heart rate variability fearful flyers: self-reported anxiety when confronting feared stimuli.

PubMed

Bornas, Xavier; Llabrés, Jordi; Noguera, Miquel; López, Ana Ma; Barceló, Francesca; Tortella-Feliu, Miquel; Fullana, Miquel Angel

2005-12-01

Previous research has shown that phobic subjects with low heart rate variability (HRV) are less able to inhibit an inappropriate response when confronted with threatening words compared to phobic subjects with high HRV [Johnsen, B.H., Thayer, J.F., Laberg, J.C., Wormnes, B., Raadal, M., Skaret, E., et al., 2003. Attentional and physiological characteristics of patients with dental anxiety. Journal of Anxiety Disorders, 17, 75-87]. The aim of this study was to evaluate changes in self-reported anxiety when low HRV and high HRV fearful flyers (N=15) and a matched control group (N=15) were exposed to flight-related pictures, flight-related sounds or both pictures and sounds. We hypothesized that sounds would be crucial to evoke fear. Also, low HRV fearful flyers were expected to report higher anxiety than high HRV fearful flyers assuming anxiety as their inappropriate response. Decreases on HRV measures were also predicted for a subgroup of phobic participants (N=10) when confronted with the feared stimuli. Our data supported the hypothesis that sounds are crucial in this kind of phobia. Low HRV fearful flyers reported higher anxiety than high HRV fearful flyers in two out of three aversive conditions. The predicted HRV decreases were not found in this study. Results are discussed in the context of avoidance of exposure-based treatments.

Laser-Launched Flyer Plates and Direct Laser Shocks for Dynamic Material Property Measurements

NASA Astrophysics Data System (ADS)

Paisley, D. L.; Swift, D. C.; Johnson, R. P.; Kopp, R. A.; Kyrala, G. A.

2002-07-01

The Trident laser at Los Alamos was used to impart known and controlled shocks in various materials by launching flyer plates or by irradiating the sample directly. Materials investigated include copper, gold, NiTi, SS316, and other metals and alloys. Tensile spall strength, elastic-plastic transition, phase boundaries, and equation of state can be determined with small samples. Using thin samples (0.1 - 1.0 mm thick) as targets, high pressure gradients can be generated with relatively low pressures, resulting in high tensile strain rates (105 to 108 s-1). Free surface and interface velocities are recorded with point- and line-imaging VISARs. The flexible spatial and temporal pulse profiles of Trident, coupled with the use of laser-launched flyer plates, provides capabilities which complement experiments conducted using gas guns and tensile bars.

A missing population of short duration gamma-ray bursts

NASA Astrophysics Data System (ADS)

Troja, Eleonora

Short duration gamma-ray bursts (GRBs) are brief and intense flashes of gamma-ray radiation located at cosmological distances. NASA s Swift mission provided the first breakthrough observations connecting these high-energy transients to the coalescence of two compact objects, either two neutron stars (NSs) or a NS and a black hole (BH). Short GRBs are therefore prime candidate electromagnetic counterparts of gravitational wave sources detectable by advanced LIGO. Unfortunately, only a fraction of short GRBs visible by Swift is promptly identified by the on-board trigger system. A larger number of events fails to pass the on-board trigger selection and goes unnoticed. Luckily, this subset of events is not lost. It is instead downlinked through a low-priority channel and then archived. The goal of this ADAP proposal is to harvest this rich population of gamma-ray transients buried in the data archive. We propose to 1) systematically mine this untapped resource of the Swift archive in order to discover new short GRBs; 2) correlate the Swift untriggered dataset with signals detected by other facilities (e.g Fermi, INTEGRAL), at other wavelengths (e.g. fast radio bursts) or with other messengers (e.g. gravitational waves); 3) develop and release the relevant tools and documentation to the community in order to facilitate the exploitation of this valuable dataset in future years. The proposed research will significantly expand the current database of short GRBs, and aid multimessenger searches of transient phenomena. By studying the behavior of matter in extreme physical conditions, the formation of new black holes, and gravity, this project directly addresses NASA Strategic Objective 1.6, a key science goal in the area of Cosmic Origins.

Applying short-duration pulses as a mean to enhance volatile organic compounds removal by air sparging

NASA Astrophysics Data System (ADS)

Ben Neriah, Asaf; Paster, Amir

2017-10-01

Application of short-duration pulses of high air pressure, to an air sparging system for groundwater remediation, was tested in a two-dimensional laboratory setup. It was hypothesized that this injection mode, termed boxcar, can enhance the remediation efficiency due to the larger ZOI and enhanced mixing which results from the pressure pulses. To test this hypothesis, flow and transport experiments were performed. Results confirm that cyclically applying short-duration pressure pulses may enhance contaminant cleanup. Comparing the boxcar to conventional continuous air-injection shows up to a three-fold increase in the single well radius of influence, dependent on the intensity of the short-duration pressure-pulses. The cleanup efficiency of Toluene from the water was 95% higher than that achieved under continuous injection with the same average conditions. This improvement was attributed to the larger zone of influence and higher average air permeability achieved in the boxcar mode, relative to continuous sparging. Mixing enhancement resultant from recurring pressure pulses was suggested as one of the mechanisms which enhance the contaminant cleanup. The application of a boxcar mode in an existing, multiwell, air sparging setup can be relatively straightforward: it requires the installation of an on-off valve in each of the injection-wells and a central control system. Then, turning off some of the wells, for a short-duration, result in a stepwise increase in injection pressure in the rest of the wells. It is hoped that this work will stimulate the additional required research and ultimately a field scale application of this new injection mode.

Short Sleep Duration Is Associated with Reduced Leptin, Elevated Ghrelin, and Increased Body Mass Index

PubMed Central

Taheri, Shahrad; Lin, Ling; Austin, Diane; Young, Terry; Mignot, Emmanuel

2004-01-01

Background Sleep duration may be an important regulator of body weight and metabolism. An association between short habitual sleep time and increased body mass index (BMI) has been reported in large population samples. The potential role of metabolic hormones in this association is unknown. Methods and Findings Study participants were 1,024 volunteers from the Wisconsin Sleep Cohort Study, a population-based longitudinal study of sleep disorders. Participants underwent nocturnal polysomnography and reported on their sleep habits through questionnaires and sleep diaries. Following polysomnography, morning, fasted blood samples were evaluated for serum leptin and ghrelin (two key opposing hormones in appetite regulation), adiponectin, insulin, glucose, and lipid profile. Relationships among these measures, BMI, and sleep duration (habitual and immediately prior to blood sampling) were examined using multiple variable regressions with control for confounding factors. A U-shaped curvilinear association between sleep duration and BMI was observed. In persons sleeping less than 8 h (74.4% of the sample), increased BMI was proportional to decreased sleep. Short sleep was associated with low leptin (p for slope = 0.01), with a predicted 15.5% lower leptin for habitual sleep of 5 h versus 8 h, and high ghrelin (p for slope = 0.008), with a predicted 14.9% higher ghrelin for nocturnal (polysomnographic) sleep of 5 h versus 8 h, independent of BMI. Conclusion Participants with short sleep had reduced leptin and elevated ghrelin. These differences in leptin and ghrelin are likely to increase appetite, possibly explaining the increased BMI observed with short sleep duration. In Western societies, where chronic sleep restriction is common and food is widely available, changes in appetite regulatory hormones with sleep curtailment may contribute to obesity. PMID:15602591

Sleep Duration, Sleep Quality, Body Mass Index, and Waist Circumference among Young Adults from 24 Low- and Middle-Income and Two High-Income Countries

PubMed Central

Peltzer, Karl; Pengpid, Supa

2017-01-01

Obesity and its comorbidities have emerged as a leading public health concern. The aim of this study was to explore the relationship between body mass index (BMI), waist circumference (WC) and sleep patterns, including duration and disturbances. A cross-sectional questionnaire survey and anthropometric measurements were conducted with undergraduate university students that were randomly recruited in 26 universities in 24 low- and middle-income and two high-income countries. The sample included 18,211 (42.1% male and 57.9% female, mean age 21.0 in male and 20.7 years in female students) undergraduate university students. The overall BMI was a mean of 22.5 kg/m2 for men and 22.0 kg/m2 for women, and the mean WC was 78.4 cm for men and 73.8 cm for women. More than 39% of the students reported short sleep duration (≤6 h/day) and over 30% reported moderate to extreme sleep problems. In a linear multivariable regression, adjusted for sociodemographic and lifestyle factors, short sleep duration was positively associated with BMI in both men and women, and was positively associated with WC among women but not among men. Sleep quality or problems among men were not associated with BMI, while among women mild sleep problems were inversely associated with BMI, and poor sleep quality or problems were positively associated with WC both among men and women. The study confirmed an association between short sleep duration and increased BMI and, among women, increased WC, and an association between poor sleep quality and increased WC but not BMI. Further, differences in the association between sleep characteristics and BMI and WC were found by region and country income. PMID:28587107

Sleep Duration, Sleep Quality, Body Mass Index, and Waist Circumference among Young Adults from 24 Low- and Middle-Income and Two High-Income Countries.

PubMed

Peltzer, Karl; Pengpid, Supa

2017-05-26

Obesity and its comorbidities have emerged as a leading public health concern. The aim of this study was to explore the relationship between body mass index (BMI), waist circumference (WC) and sleep patterns, including duration and disturbances. A cross-sectional questionnaire survey and anthropometric measurements were conducted with undergraduate university students that were randomly recruited in 26 universities in 24 low- and middle-income and two high-income countries. The sample included 18,211 (42.1% male and 57.9% female, mean age 21.0 in male and 20.7 years in female students) undergraduate university students. The overall BMI was a mean of 22.5 kg/m² for men and 22.0 kg/m² for women, and the mean WC was 78.4 cm for men and 73.8 cm for women. More than 39% of the students reported short sleep duration (≤6 h/day) and over 30% reported moderate to extreme sleep problems. In a linear multivariable regression, adjusted for sociodemographic and lifestyle factors, short sleep duration was positively associated with BMI in both men and women, and was positively associated with WC among women but not among men. Sleep quality or problems among men were not associated with BMI, while among women mild sleep problems were inversely associated with BMI, and poor sleep quality or problems were positively associated with WC both among men and women. The study confirmed an association between short sleep duration and increased BMI and, among women, increased WC, and an association between poor sleep quality and increased WC but not BMI. Further, differences in the association between sleep characteristics and BMI and WC were found by region and country income.

Short-term memory for spatial, sequential and duration information.

PubMed

Manohar, Sanjay G; Pertzov, Yoni; Husain, Masud

2017-10-01

Space and time appear to play key roles in the way that information is organized in short-term memory (STM). Some argue that they are crucial contexts within which other stored features are embedded, allowing binding of information that belongs together within STM. Here we review recent behavioral, neurophysiological and imaging studies that have sought to investigate the nature of spatial, sequential and duration representations in STM, and how these might break down in disease. Findings from these studies point to an important role of the hippocampus and other medial temporal lobe structures in aspects of STM, challenging conventional accounts of involvement of these regions in only long-term memory.

Analysis of vestibular-balance symptoms according to symptom duration: dimensionality of the Vertigo Symptom Scale-short form.

PubMed

Kondo, Masaki; Kiyomizu, Kensuke; Goto, Fumiyuki; Kitahara, Tadashi; Imai, Takao; Hashimoto, Makoto; Shimogori, Hiroaki; Ikezono, Tetsuo; Nakayama, Meiho; Watanabe, Norio; Akechi, Tatsuo

2015-01-22

Dizziness or vertigo is associated with both vestibular-balance and psychological factors. A common assessment tool is the Vertigo Symptom Scale (VSS) -short form, which has two subscales: vestibular-balance and autonomic-anxiety. Despite frequent use, the factor structure of the VSS-short form has yet to be confirmed. Here, we clarified the factor structure of the VSS-short form, and assessed the validity and reliability of the Japanese version of this tool. We conducted a cross-sectional, multicenter, psychometric evaluation of patients with non-central dizziness or vertigo persisting for longer than 1 month. Participants completed the VSS-short form, the Dizziness Handicap Inventory, and the Hospital Anxiety and Depression Scale. They also completed the VSS-short form a second time 1-3 days later. The questionnaire was translated into Japanese and cross-culturally adapted. We conducted a confirmatory factor analysis followed by an exploratory factor analysis. Convergent and discriminant validity, internal consistency, and test-retest reliability were evaluated. The total sample and retest sample consisted of 159 and 79 participants, respectively. Model-fitting for a two-subscale structure in a confirmatory factor analysis was poor. An exploratory factor analysis produced a three-factor structure: long-duration vestibular-balance symptoms, short-duration vestibular-balance symptoms, and autonomic-anxiety symptoms. Regarding convergent and discriminant validity, all hypotheses were clearly supported. We obtained high Cronbach's α coefficients for the total score and subscales, ranging from 0.758 to 0.866. Total score and subscale interclass correlation coefficients for test-retest reliability were acceptable, ranging from 0.867 to 0.897. The VSS-short form has a three-factor structure that was cross-culturally well-matched with previous data from the VSS-long version. Thus, it was suggested that vestibular-balance symptoms can be analyzed separately according to

Does hyperthermia constrain flight duration in a short-distance migrant?

PubMed Central

Guillemette, Magella; Larochelle, Jacques; Polymeropoulos, Elias T.; Granbois, Jean-Marc; Butler, Patrick J.; Pelletier, David; Frappell, Peter B.; Portugal, Steven J.

2016-01-01

While some migratory birds perform non-stop flights of over 11 000 km, many species only spend around 15% of the day in flight during migration, posing a question as to why flight times for many species are so short. Here, we test the idea that hyperthermia might constrain flight duration (FD) in a short-distance migrant using remote biologging technology to measure heart rate, hydrostatic pressure and body temperature in 19 migrating eider ducks (Somateria mollissima), a short-distance migrant. Our results reveal a stop-and-go migration strategy where migratory flights were frequent (14 flights day−1) and short (15.7 min), together with the fact that body temperature increases by 1°C, on average, during such flights, which equates to a rate of heat storage index (HSI) of 4°C h−1. Furthermore, we could not find any evidence that short flights were limited by heart rate, together with the fact that the numerous stops could not be explained by the need to feed, as the frequency of dives and the time spent feeding were comparatively small during the migratory period. We thus conclude that hyperthermia appears to be the predominant determinant of the observed migration strategy, and suggest that such a physiological limitation to FD may also occur in other species. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’. PMID:27528776

Does hyperthermia constrain flight duration in a short-distance migrant?

PubMed

Guillemette, Magella; Woakes, Anthony J; Larochelle, Jacques; Polymeropoulos, Elias T; Granbois, Jean-Marc; Butler, Patrick J; Pelletier, David; Frappell, Peter B; Portugal, Steven J

2016-09-26

While some migratory birds perform non-stop flights of over 11 000 km, many species only spend around 15% of the day in flight during migration, posing a question as to why flight times for many species are so short. Here, we test the idea that hyperthermia might constrain flight duration (FD) in a short-distance migrant using remote biologging technology to measure heart rate, hydrostatic pressure and body temperature in 19 migrating eider ducks (Somateria mollissima), a short-distance migrant. Our results reveal a stop-and-go migration strategy where migratory flights were frequent (14 flights day(-1)) and short (15.7 min), together with the fact that body temperature increases by 1°C, on average, during such flights, which equates to a rate of heat storage index (HSI) of 4°C h(-1) Furthermore, we could not find any evidence that short flights were limited by heart rate, together with the fact that the numerous stops could not be explained by the need to feed, as the frequency of dives and the time spent feeding were comparatively small during the migratory period. We thus conclude that hyperthermia appears to be the predominant determinant of the observed migration strategy, and suggest that such a physiological limitation to FD may also occur in other species.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. © 2016 The Author(s).

Prevalence of sleep duration among Saudi adults

PubMed Central

Ahmed, Anwar E.; Al-Jahdali, Fares; AlALwan, Abdulaziz; Abuabat, Faisal; Salih, Salih Bin; Al-Harbi, Abdullah; Baharoon, Salim; Khan, Mohammad; Ali, Yosra Z.; Al-Jahdali, Hamdan

2017-01-01

Objectives: To examine the associations between sleep duration and a variety of demographic and clinical variables in a sample of Saudi adults. Methods: A cross-sectional study among 2,095 participants was conducted at King Abdulaziz Medical City, Riyadh, Kingdom of Saudi Arabia, between May and October 2014. A questionnaire was administered to collect data related to clinical health outcomes and demographic characteristics. Participants were asked to report their average sleep duration per night in hours. Results: One-third (33.8%) reported short sleep duration of less than 7 hours/night. Short sleep duration was more prevalent in females (37.3% versus 31.4%, p=0.004). The most common medical problems reported were obesity with body mass index of >30 Kg/m2 (39.1%), hypertension (33.9%), diabetes mellitus (20.8%), depression (4.3%), asthma (17.3%), COPD (6.6%), and hyperlipidemia (2.7%). Diabetes mellitus was associated with long sleep of more than 9 hours/night (25.4%, p=0.011) and hypertension (54.2%, p=0.001). The linear regression model tend to reduce their sleep duration by roughly 22 minutes in female gender, 66 minutes in participants with hyperlipidemia, and 70 minutes in participants with poor sleep quality. Conclusions: Short sleep duration per night was prevalent, it affects one in every 3 Saudi adults. Long sleep duration of more than 9 hours was associated with increased comorbid conditions. PMID:28251223

On the Pressure Response in the Brain due to Short Duration Blunt Impacts

PubMed Central

Pearce, Christopher W.; Young, Philippe G.

2014-01-01

When the head is subject to non-penetrating (blunt) impact, contusion-type injuries are commonly identified beneath the impact site (the coup) and, in some instances, at the opposite pole (the contre-coup). This pattern of injury has long eluded satisfactory explanation and blunt head injury mechanisms in general remain poorly understood. There are only a small number of studies in the open literature investigating the head's response to short duration impacts, which can occur in collisions with light projectiles. As such, the head impact literature to date has focussed almost exclusively on impact scenarios which lead to a quasi-static pressure response in the brain. In order to investigate the response of the head to a wide range of impact durations, parametric numerical studies were performed on a highly bio-fidelic finite element model of the human head created from in vivo magnetic resonance imaging (MRI) scan data with non-linear tissue material properties. We demonstrate that short duration head impacts can lead to potentially deleterious transients of positive and negative intra-cranial pressure over an order of magnitude larger than those observed in the quasi-static regime despite reduced impact force and energy. The onset of this phenomenon is shown to be effectively predicted by the ratio of impact duration to the period of oscillation of the first ovalling mode of the system. These findings point to dramatically different pressure distributions in the brain and hence different patterns of injury depending on projectile mass, and provide a potential explanation for dual coup/contre-coup injuries observed clinically. PMID:25478695

On the pressure response in the brain due to short duration blunt impacts.

PubMed

Pearce, Christopher W; Young, Philippe G

2014-01-01

When the head is subject to non-penetrating (blunt) impact, contusion-type injuries are commonly identified beneath the impact site (the coup) and, in some instances, at the opposite pole (the contre-coup). This pattern of injury has long eluded satisfactory explanation and blunt head injury mechanisms in general remain poorly understood. There are only a small number of studies in the open literature investigating the head's response to short duration impacts, which can occur in collisions with light projectiles. As such, the head impact literature to date has focussed almost exclusively on impact scenarios which lead to a quasi-static pressure response in the brain. In order to investigate the response of the head to a wide range of impact durations, parametric numerical studies were performed on a highly bio-fidelic finite element model of the human head created from in vivo magnetic resonance imaging (MRI) scan data with non-linear tissue material properties. We demonstrate that short duration head impacts can lead to potentially deleterious transients of positive and negative intra-cranial pressure over an order of magnitude larger than those observed in the quasi-static regime despite reduced impact force and energy. The onset of this phenomenon is shown to be effectively predicted by the ratio of impact duration to the period of oscillation of the first ovalling mode of the system. These findings point to dramatically different pressure distributions in the brain and hence different patterns of injury depending on projectile mass, and provide a potential explanation for dual coup/contre-coup injuries observed clinically.

Short sleep duration is associated with eating more carbohydrates and less dietary fat in Mexican American Children

USDA-ARS?s Scientific Manuscript database

Short sleep duration is a risk factor for childhood obesity. Mechanisms are unclear, but may involve selection of high carbohydrate foods. This study examined the association between estimated sleep duration and macronutrient intake as percentages of total energy among Mexican American (MA) 9-11 yea...

Applying short-duration pulses as a mean to enhance volatile organic compounds removal by air sparging.

PubMed

Ben Neriah, Asaf; Paster, Amir

2017-10-01

Application of short-duration pulses of high air pressure, to an air sparging system for groundwater remediation, was tested in a two-dimensional laboratory setup. It was hypothesized that this injection mode, termed boxcar, can enhance the remediation efficiency due to the larger ZOI and enhanced mixing which results from the pressure pulses. To test this hypothesis, flow and transport experiments were performed. Results confirm that cyclically applying short-duration pressure pulses may enhance contaminant cleanup. Comparing the boxcar to conventional continuous air-injection shows up to a three-fold increase in the single well radius of influence, dependent on the intensity of the short-duration pressure-pulses. The cleanup efficiency of Toluene from the water was 95% higher than that achieved under continuous injection with the same average conditions. This improvement was attributed to the larger zone of influence and higher average air permeability achieved in the boxcar mode, relative to continuous sparging. Mixing enhancement resultant from recurring pressure pulses was suggested as one of the mechanisms which enhance the contaminant cleanup. The application of a boxcar mode in an existing, multiwell, air sparging setup can be relatively straightforward: it requires the installation of an on-off valve in each of the injection-wells and a central control system. Then, turning off some of the wells, for a short-duration, result in a stepwise increase in injection pressure in the rest of the wells. It is hoped that this work will stimulate the additional required research and ultimately a field scale application of this new injection mode. Copyright © 2017 Elsevier B.V. All rights reserved.

Short amplexus duration in a territorial anuran: a possible adaptation in response to male-male competition.

PubMed

Chuang, Ming-Feng; Bee, Mark A; Kam, Yeong-Choy

2013-01-01

Mating duration is a reproductive behaviour that can impact fertilization efficiency and offspring number. Previous studies of factors influencing the evolution of mating duration have focused on the potential role of internal sperm competition as an underlying source of selection; most of these studies have been on invertebrates. For vertebrates with external fertilization, such as fishes and frogs, the sources of selection acting on mating duration remain largely unknown due, in part, to the difficulty of observing complete mating behaviours in natural conditions. In this field study, we monitored breeding activity in a population of the territorial olive frog, Rana adenopleura, to identify factors that affect the duration of amplexus. Compared with most other frogs, amplexus was short, lasting less than 11 min on average, which included about 8 min of pre-oviposition activity followed by 3 min of oviposition. We evaluated the relationship between amplexus duration and seven variables: male body size, male condition, operational sex ratio (OSR), population size, clutch size, territory size, and the coverage of submerged vegetation in a male's territory. We also investigated the influence of these same variables, along with amplexus duration, on fertilization rate. Amplexus duration was positively related with clutch size and the degree of male-bias in the nightly OSR. Fertilization rate was directly related to male body size and inversely related to amplexus duration. Agonistic interactions between males in amplexus and intruding, unpaired males were frequent. These interactions often resulted in mating failure, prolonged amplexus duration, and reduced fertilization rates. Together, the pattern of our findings indicates short amplexus duration in this species may be an adaptive reproductive strategy whereby males attempt to reduce the risks of mating and fertilization failures and territory loss resulting from male-male competition.

Atrial fibrillation ablation using very short duration 50 W ablations and contact force sensing catheters.

PubMed

Winkle, Roger A; Moskovitz, Ryan; Hardwin Mead, R; Engel, Gregory; Kong, Melissa H; Fleming, William; Salcedo, Jonathan; Patrawala, Rob A; Tranter, John H; Shai, Isaac

2018-06-01

The optimal radiofrequency (RF) power and lesion duration using contact force (CF) sensing catheters for atrial fibrillation (AF) ablation are unknown. We evaluate 50 W RF power for very short durations using CF sensing catheters during AF ablation. We evaluated 51 patients with paroxysmal (n = 20) or persistent (n = 31) AF undergoing initial RF ablation. A total of 3961 50 W RF lesions were given (average 77.6 ± 19.1/patient) for an average duration of only 11.2 ± 3.7 s. As CF increased from < 10 to > 40 g, the RF application duration decreased from 13.7 ± 4.4 to 8.6 ± 2.5 s (p < 0.0005). Impedance drops occurred in all ablations, and for patients in sinus rhythm, there was loss of pacing capture during RF delivery suggesting lesion creation. Only 3% of the ablation lesions were at < 5 g and 1% at > 40 g of force. As CF increased, the force time integral (FTI) increased from 47 ± 24 to 376 ± 102 gs (p < 0.0005) and the lesion index (LSI) increased from 4.10 ± 0.51 to 7.63 ± 0.50 (p < 0.0005). Both procedure time (101 ± 19.7 min) and total RF energy time (895 ± 258 s) were very short. For paroxysmal AF, the single procedure freedom from AF was 86% at 1 and 2 years. For persistent AF, it was 83% at 1 year and 72% at 2 years. There were no complications. Short duration 50 W ablations using CF sensing catheters are safe and result in excellent long-term freedom from AF for both paroxysmal and persistent AF with short procedure times and small amounts of total RF energy delivery.

Short Sleep Duration Increases Metabolic Impact in Healthy Adults: A Population-Based Cohort Study.

PubMed

Deng, Han-Bing; Tam, Tony; Zee, Benny Chung-Ying; Chung, Roger Yat-Nork; Su, Xuefen; Jin, Lei; Chan, Ta-Chien; Chang, Ly-Yun; Yeoh, Eng-Kiong; Lao, Xiang Qian

2017-10-01

The metabolic impact of inadequate sleep has not been determined in healthy individuals outside laboratories. This study aims to investigate the impact of sleep duration on five metabolic syndrome components in a healthy adult cohort. A total of 162121 adults aged 20-80 years (men 47.4%) of the MJ Health Database, who were not obese and free from major diseases, were recruited and followed up from 1996 to 2014. Sleep duration and insomnia symptoms were assessed by a self-administered questionnaire. Incident cases of five metabolic syndrome components were identified by follow-up medical examinations. Cox proportional hazard ratios (HRs) were calculated for three sleep duration categories "< 6 hours/day (short)," "6-8 hours/day (regular)," and "> 8 hours/day (long)" with adjustment for potential confounding factors. Analyses were stratified by insomnia symptoms to assess whether insomnia symptoms modified the association between sleep duration and metabolic syndrome. Compared to regular sleep duration, short sleep significantly (p < .001) increased the risk for central obesity by 12% (adjusted HR 1.12 [1.07-1.17]), for elevated fasting glucose by 6% (adjusted HR 1.06 [1.03-1.09]), for high blood pressure by 8% (adjusted HR 1.08 [1.04-1.13]), for low high-density lipoprotein-cholesterol by 7% (adjusted HR 1.07 [1.03-1.11]), for hypertriglyceridemia by 9% (adjusted HR 1.09 [1.05-1.13]), and for metabolic syndrome by 9% (adjusted HR 1.09 [1.05-1.13]). Long sleep decreased the risk of hypertriglyceridemia (adjusted HR 0.89 [0.84-0.94]) and metabolic syndrome (adjusted HR 0.93 [0.88-0.99]). Insomnia symptoms did not modify the effects of sleep duration. Sleep duration may be a significant determinant of metabolic health. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

An exceptionally bright flare from SGR 1806-20 and the origins of short-duration gamma-ray bursts.

PubMed

Hurley, K; Boggs, S E; Smith, D M; Duncan, R C; Lin, R; Zoglauer, A; Krucker, S; Hurford, G; Hudson, H; Wigger, C; Hajdas, W; Thompson, C; Mitrofanov, I; Sanin, A; Boynton, W; Fellows, C; von Kienlin, A; Lichti, G; Rau, A; Cline, T

2005-04-28

Soft-gamma-ray repeaters (SGRs) are galactic X-ray stars that emit numerous short-duration (about 0.1 s) bursts of hard X-rays during sporadic active periods. They are thought to be magnetars: strongly magnetized neutron stars with emissions powered by the dissipation of magnetic energy. Here we report the detection of a long (380 s) giant flare from SGR 1806-20, which was much more luminous than any previous transient event observed in our Galaxy. (In the first 0.2 s, the flare released as much energy as the Sun radiates in a quarter of a million years.) Its power can be explained by a catastrophic instability involving global crust failure and magnetic reconnection on a magnetar, with possible large-scale untwisting of magnetic field lines outside the star. From a great distance this event would appear to be a short-duration, hard-spectrum cosmic gamma-ray burst. At least a significant fraction of the mysterious short-duration gamma-ray bursts may therefore come from extragalactic magnetars.

Validation of Procedures for Monitoring Crewmember Immune Function - Short Duration Biological Investigation

NASA Technical Reports Server (NTRS)

Sams, Clarence; Crucian, Brian; Stowe, Raymond; Pierson, Duane; Mehta, Satish; Morukov, Boris; Uchakin, Peter; Nehlsen-Cannarella, Sandra

2008-01-01

Validation of Procedures for Monitoring Crew Member Immune Function - Short Duration Biological Investigation (Integrated Immune-SDBI) will assess the clinical risks resulting from the adverse effects of space flight on the human immune system and will validate a flightcompatible immune monitoring strategy. Immune system changes will be monitored by collecting and analyzing blood, urine and saliva samples from crewmembers before, during and after space flight.

Thermal latency adds to lesion depth after application of high-power short-duration radiofrequency energy: Results of a computer-modeling study.

PubMed

Irastorza, Ramiro M; d'Avila, Andre; Berjano, Enrique

2018-02-01

The use of ultra-short RF pulses could achieve greater lesion depth immediately after the application of the pulse due to thermal latency. A computer model of irrigated-catheter RF ablation was built to study the impact of thermal latency on the lesion depth. The results showed that the shorter the RF pulse duration (keeping energy constant), the greater the lesion depth during the cooling phase. For instance, after a 10-second pulse, lesion depth grew from 2.05 mm at the end of the pulse to 2.39 mm (17%), while after an ultra-short RF pulse of only 1 second the extra growth was 37% (from 2.22 to 3.05 mm). Importantly, short applications resulted in deeper lesions than long applications (3.05 mm vs. 2.39 mm, for 1- and 10-second pulse, respectively). While shortening the pulse duration produced deeper lesions, the associated increase in applied voltage caused overheating in the tissue: temperatures around 100 °C were reached at a depth of 1 mm in the case of 1- and 5-second pulses. However, since the lesion depth increased during the cooling period, lower values of applied voltage could be applied in short durations in order to obtain lesion depths similar to those in longer durations while avoiding overheating. The thermal latency phenomenon seems to be the cause of significantly greater lesion depth after short-duration high-power RF pulses. Balancing the applied total energy when the voltage and duration are changed is not the optimal strategy since short pulses can also cause overheating. © 2017 Wiley Periodicals, Inc.

Short duration repetitive transcranial magnetic stimulation for tinnitus treatment: a prospective Asian study.

PubMed

Ting, S K S; Chan, Y M; Cheong, P W T; Wong, M; Fook-Chong, S; Lo, Y L

2011-09-01

Tinnitus is a subjective auditory perception of sounds or noise not triggered by external auditory stimuli. To date, treatment in severe cases is generally unsatisfactory. Characteristic functional brain imaging changes associated with tinnitus include hyperactivity encompassing both the primary auditory cortex (AC) and the secondary or associative cortex. Brief repetitive transcranial magnetic stimulation (rTMS) trains applied to the scalp overlying the hyperactive left AC is known to produce moderate tinnitus attenuation. Although Western studies have documented the value of rTMS in tinnitus treatment, we evaluate the efficacy of a short duration rTMS protocol for the first time in the Asian setting. Consecutive patients were recruited at our tinnitus clinic. Detailed history, examination, audiogram and baseline tinnitus scales were recorded. RTMS consisted of 1000 pulses/day at 1 Hz and 110% of the motor threshold, for five consecutive days over the left temporoparietal cortex. Tinnitus ratings were determined weekly for 4 weeks after rTMS. Fifteen patients completed the trial; none experienced significant side effects. Repeated measures ANOVA showed significant linear decrease in Tinnitus Handicap Inventory (THI) scores over the time period (F((1,14))=4.7, p=0.04). However, none of the other parameters (severity, annoyance, effect on lifestyle and overall impression: visual analogue scale) showed beneficial outcomes. Our findings point to a positive effect of short duration rTMS in tinnitus treatment using the THI. However, no significant benefits were demonstrated for other subjective patient ratings. Although well tolerated and convenient, short duration rTMS may prove inadequate for modulating maladaptive plastic changes at the cortical level, and our results suggest the need for delivery of more stimuli. Future studies will utilize at least 2000 pulses/day, in line with previous experience in Western settings. Copyright © 2011 Elsevier B.V. All rights

DEMOGRAPHICS OF THE GALAXIES HOSTING SHORT-DURATION GAMMA-RAY BURSTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fong, W.; Berger, E.; Chornock, R.

We present observations of the afterglows and host galaxies of three short-duration gamma-ray bursts (GRBs): 100625A, 101219A, and 110112A. We find that GRB 100625A occurred in a z = 0.452 early-type galaxy with a stellar mass of Almost-Equal-To 4.6 Multiplication-Sign 10{sup 9} M{sub Sun} and a stellar population age of Almost-Equal-To 0.7 Gyr, and GRB 101219A originated in a star-forming galaxy at z = 0.718 with a stellar mass of Almost-Equal-To 1.4 Multiplication-Sign 10{sup 9} M{sub Sun }, a star formation rate of Almost-Equal-To 16 M{sub Sun} yr{sup -1}, and a stellar population age of Almost-Equal-To 50 Myr. We alsomore » report the discovery of the optical afterglow of GRB 110112A, which lacks a coincident host galaxy to i {approx}> 26 mag, and we cannot conclusively identify any field galaxy as a possible host. From afterglow modeling, the bursts have inferred circumburst densities of Almost-Equal-To 10{sup -4}-1 cm{sup -3} and isotropic-equivalent gamma-ray and kinetic energies of Almost-Equal-To 10{sup 50}-10{sup 51} erg. These three events highlight the diversity of galactic environments that host short GRBs. To quantify this diversity, we use the sample of 36 Swift short GRBs with robust associations to an environment ({approx}1/2 of 68 short bursts detected by Swift to 2012 May) and classify bursts originating from four types of environments: late-type ( Almost-Equal-To 50%), early-type ( Almost-Equal-To 15%), inconclusive ( Almost-Equal-To 20%), and ''host-less'' (lacking a coincident host galaxy to limits of {approx}> 26 mag; Almost-Equal-To 15%). To find likely ranges for the true late- and early-type fractions, we assign each of the host-less bursts to either the late- or early-type category using probabilistic arguments and consider the scenario that all hosts in the inconclusive category are early-type galaxies to set an upper bound on the early-type fraction. We calculate most likely ranges for the late- and early-type fractions of Almost

State of the practice for workers in very short duration work zone operations : educational module.

DOT National Transportation Integrated Search

2012-07-01

After finishing this module, you will know : WHAT should be considered as Very Short Duration Operations (VSDOs) : WHY is risk assessment important for VSDOs : HOW to properly assess risk and make better judgments in VSDOs

Web Page Development and Management. SPEC Kit 246 and SPEC Flyer 246.

ERIC Educational Resources Information Center

Liu, Yaping Peter, Comp.

This SPEC (Systems and Procedures Exchange Center) Kit and Flyer reports results of two surveys conducted in 1996 and 1998 that examined ARL (Association of Research Libraries) member libraries' World Wide Web history, development, use, and activities. Fifty-six out of the then 119 ARL member institutions responded to the 1996 survey, and 68 out…

Sleep duration and sleep quality are associated differently with alterations of glucose homeostasis.

PubMed

Byberg, S; Hansen, A-L S; Christensen, D L; Vistisen, D; Aadahl, M; Linneberg, A; Witte, D R

2012-09-01

Studies suggest that inadequate sleep duration and poor sleep quality increase the risk of impaired glucose regulation and diabetes. However, associations with specific markers of glucose homeostasis are less well explained. The objective of this study was to explore possible associations of sleep duration and sleep quality with markers of glucose homeostasis and glucose tolerance status in a healthy population-based study sample. The study comprised 771 participants from the Danish, population-based cross-sectional 'Health2008' study. Sleep duration and sleep quality were measured by self-report. Markers of glucose homeostasis were derived from a 3-point oral glucose tolerance test and included fasting plasma glucose, 2-h plasma glucose, HbA(1c), two measures of insulin sensitivity (the insulin sensitivity index(0,120) and homeostasis model assessment of insulin sensitivity), the homeostasis model assessment of β-cell function and glucose tolerance status. Associations of sleep duration and sleep quality with markers of glucose homeostasis and tolerance were analysed by multiple linear and logistic regression. A 1-h increment in sleep duration was associated with a 0.3 mmol/mol (0.3%) decrement in HbA(1c) and a 25% reduction in the risk of having impaired glucose regulation. Further, a 1-point increment in sleep quality was associated with a 2% increase in both the insulin sensitivity index(0,120) and homeostasis model assessment of insulin sensitivity, as well as a 1% decrease in homeostasis model assessment of β-cell function. In the present study, shorter sleep duration was mainly associated with later alterations in glucose homeostasis, whereas poorer sleep quality was mainly associated with earlier alterations in glucose homeostasis. Thus, adopting healthy sleep habits may benefit glucose metabolism in healthy populations. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.

Femoral Head Bone Loss Following Short and Long-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Blaber, E. A.; Cheng-Campbell, M.; Almeida, E. A. C.

2016-01-01

Exposure to mechanical unloading during spaceflight is known to have significant effects on the musculoskeletal system. Our ongoing studies with the mouse bone model have identified the failure of normal stem cell-based tissue regeneration, in addition to tissue degeneration, as a significant concern for long-duration spaceflight, especially in the mesenchymal and hematopoietic tissue lineages. The 30-day BionM1 and the 37-day Rodent Research 1 (RR1) missions enabled the possibility of studying these effects in long-duration microgravity experiments. We hypothesized that the inhibition of stem cell-based tissue regeneration in short-duration spaceflight would continue during long-duration spaceflight and furthermore would result in significant tissue alterations. MicroCT analysis of BionM1 femurs revealed 31% decrease in bone volume ratio, a 14% decrease in trabecular thickness, and a 20% decrease in trabecular number in the femoral head of space-flown mice. Furthermore, high-resolution MicroCT and immunohistochemical analysis of spaceflight tissues revealed a severe disruption of the epiphyseal boundary, resulting in endochondral ossification of the femoral head and perforation of articular cartilage by bone. This suggests that spaceflight in microgravity may cause rapid induction of an aging-like phenotype with signs of osteoarthritic disease in the hip joint. However, mice from RR1 exhibited significant bone loss in the femoral head but did not exhibit the severe aging and disease-like phenotype observed during BionM1.This may be due to increased physical activity in the RH hardware. Immunohistochemical analysis of the epiphyseal plate and investigation of cellular proliferation and differentiation pathways within the marrow compartment and whole bone tissue is currently being conducted to determine alterations in stem cell-based tissue regeneration between these experiments. Our results show that the observed inhibition of stem cell-based tissue regeneration

Femoral Head Bone Loss Following Short and Long-Duration Spaceflight

NASA Technical Reports Server (NTRS)

Blaber, Elizabeth A.; Cheng-Campbell, Margareth A.; Almeida, Eduardo A. C.

2016-01-01

Exposure to mechanical unloading during spaceflight is known to have significant effects on the musculoskeletal system. Our ongoing studies with the mouse bone model have identified the failure of normal stem cell-based tissue regeneration, in addition to tissue degeneration, as a significant concern for long-duration spaceflight, especially in the mesenchymal and hematopoietic tissue lineages. The 30-day BionM1 and the 37-day Rodent Research 1 (RR1) missions enabled the possibility of studying these effects in long-duration microgravity experiments. We hypothesized that the inhibition of stem cell-based tissue regeneration in short-duration spaceflight would continue during long-duration spaceflight and furthermore would result in significant tissue alterations. MicroCT analysis of BionM1 femurs revealed 31 decrease in bone volume ratio, a 14 decrease in trabecular thickness, and a 20 decrease in trabecular number in the femoral head of space-flown mice. Furthermore, high-resolution MicroCT and immunohistochemical analysis of spaceflight tissues revealed a severe disruption of the epiphyseal boundary, resulting in endochondral ossification of the femoral head and perforation of articular cartilage by bone. This suggests that spaceflight in microgravity may cause rapid induction of an aging-like phenotype with signs of osteoarthritic disease in the hip joint. However, mice from RR1 exhibited significant bone loss in the femoral head but did not exhibit the severe aging and disease-like phenotype observed during BionM1. This may be due to increased physical activity in the RH hardware. Immunohistochemical analysis of the epiphyseal plate and investigation of cellular proliferation and differentiation pathways within the marrow compartment and whole bone tissue is currently being conducted to determine alterations in stem cell-based tissue regeneration between these experiments. Our results show that the observed inhibition of stem cell-based tissue regeneration

Sleep quality, sleep duration and physical activity in obese adolescents: effects of exercise training.

PubMed

Mendelson, M; Borowik, A; Michallet, A-S; Perrin, C; Monneret, D; Faure, P; Levy, P; Pépin, J-L; Wuyam, B; Flore, P

2016-02-01

Decreased sleep duration and altered sleep quality are risk factors for obesity in youth. Structured exercise training has been shown to increase sleep duration and improve sleep quality. This study aimed at evaluating the impact of exercise training for improving sleep duration, sleep quality and physical activity in obese adolescents (OB). Twenty OB (age: 14.5 ± 1.5 years; body mass index: 34.0 ± 4.7 kg m(-2) ) and 20 healthy-weight adolescents (HW) completed an overnight polysomnography and wore an accelerometer (SenseWear Bodymedia) for 7 days. OB participated in a 12-week supervised exercise-training programme consisting of 180 min of exercise weekly. Exercise training was a combination of aerobic exercise and resistance training. Sleep duration was greater in HW compared with OB (P < 0.05). OB presented higher apnoea-hypopnoea index than HW (P < 0.05). Physical activity (average daily metabolic equivalent of tasks [METs]) by accelerometer was lower in OB (P < 0.05). After exercise training, obese adolescents increased their sleep duration (+64.4 min; effect size: 0.88; P = 0.025) and sleep efficiency (+7.6%; effect size: 0.76; P = 0.028). Physical activity levels were increased in OB as evidenced by increased steps per day and average daily METs (P < 0.05). Improved sleep duration was associated with improved average daily METs (r = 0.48, P = 0.04). The present study confirms altered sleep duration and quality in OB. Exercise training improves sleep duration, sleep quality and physical activity. © 2015 World Obesity.

Short self-reported sleep duration and suicidal behavior: a cross-sectional study.

PubMed

Blasco-Fontecilla, Hilario; Alegria, Analucia A; Lopez-Castroman, Jorge; Legido-Gil, Teresa; Saiz-Ruiz, Jeronimo; de Leon, Jose; Baca-Garcia, Enrique

2011-09-01

Prior studies on the association between sleep disturbances and suicidal behavior did not explore whether or not short sleep is a marker of suicide intent, lethality or risk. Cross-sectional. Suicide attempters (SAs) (n=434). Controls included 83 psychiatric inpatients who have never been SAs, and 509 healthy controls. Short sleep was defined by self-assessment as ≤ 5 h per day. The MINI and the DSM-IV version of the International Personality Disorder Examination Screening Questionnaire were used to diagnose Axis I and Axis II diagnoses, respectively. Suicide intent and lethality were evaluated through the Beck's Suicidal Intent Scale (SIS) and the Risk-Rescue Rating Scale (RRRS), respectively. Beck's Medical Lethality Scale (BMLS) was administered to assess the degree of medical injury, and the SAD PERSONS mnemonic scale was used to evaluate suicide risk. Chi-square tests and logistic regression analyses explored frequencies of short sleep in 3 samples. Chi-square tests explored whether or not suicide intent, lethality and risk were greater in SAs with short-sleep versus those without short-sleep. Short sleep was more prevalent in SAs than in psychiatric controls only in males. In female SAs, short sleep was significantly associated with several SIS items and high scores in the SAD PERSONS. Sleep duration was assessed only by self-report. The association between short sleep and suicidal behavior may be partly explained by confounders. Short sleep may be a marker of severity of suicidal behavior among female SAs. Copyright © 2011 Elsevier B.V. All rights reserved.

Sleep duration and age-related changes in brain structure and cognitive performance.

PubMed

Lo, June C; Loh, Kep Kee; Zheng, Hui; Sim, Sam K Y; Chee, Michael W L

2014-07-01

To investigate the contribution of sleep duration and quality to age-related changes in brain structure and cognitive performance in relatively healthy older adults. Community-based longitudinal brain and cognitive aging study using a convenience sample. Participants were studied in a research laboratory. Relatively healthy adults aged 55 y and older at study commencement. N/A. Participants underwent magnetic resonance imaging and neuropsychological assessment every 2 y. Subjective assessments of sleep duration and quality and blood samples were obtained. Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59% (P = 0.007) and the annual decline rate in global cognitive performance by 0.67% (P = 0.050) in the subsequent 2 y after controlling for the effects of age, sex, education, and body mass index. In contrast, global sleep quality at baseline did not modulate either brain or cognitive aging. High-sensitivity C-reactive protein, a marker of systemic inflammation, showed no correlation with baseline sleep duration, brain structure, or cognitive performance. In healthy older adults, short sleep duration is associated with greater age-related brain atrophy and cognitive decline. These associations are not associated with elevated inflammatory responses among short sleepers. Lo JC, Loh KK, Zheng H, Sim SK, Chee MW. Sleep duration and age-related changes in brain structure and cognitive performance.

Assessment of crew operations during internal servicing of the Columbus Free-Flyer by Hermes

NASA Astrophysics Data System (ADS)

Winisdoerffer, F.; Lamothe, A.; Bourdeau'hui, J. C.

The Hermes system has been adopted as a European programme at the Hague ministerial level meeting. The primary mission of the Hermes spaceplane will be the servicing of the Columbus Free-Flyer (CFF) in order to bring new experiments in orbit, recover the results of old ones, and refurbish/maintain the various subsystems. This mission will be based on the extensive use of the 3 crewmembers on-board Hermes in order to perform either the Intra-Vehicular (IVA) and/or the Extra-Vehicular (EVA) activities. This paper focuses on the internal operations and the dimensions of the various payload of the basic reference cargo set are presented. The main constraints associated with their manipulation are also assessed independently of the configuration. During the spaceplane definition process, various configurations were developed. The operations were simulated using the CAD CATIA software with representative anthropometric models of the potential Hermes users population. These simulations helped to assess the various configurations and to refine the general concept of the spaceplane. The geometrical feasibility is demonstrated through those simulations. However full-scale tests are required to confirm data and assess the duration of the operations.

Intelligent Control for the BEES Flyer

NASA Technical Reports Server (NTRS)

Krishnakumar, K.; Gundy-Burlet, Karen; Aftosmis, Mike; Nemec, Marian; Limes, Greg; Berry, Misty; Logan, Michael

2004-01-01

This paper describes the effort to provide a preliminary capability analysis and a neural network based adaptive flight control system for the JPL-led BEES aircraft project. The BEES flyer was envisioned to be a small, autonomous platform with sensing and control systems mimicking those of biological systems for the purpose of scientific exploration on the surface of Mars. The platform is physically tightly constrained by the necessity of efficient packing within rockets for the trip to Mars. Given the physical constraints, the system is not an ideal configuration for aerodynamics or stability and control. The objectives of this effort are to evaluate the aerodynamics characteristics of the existing design, to make recommendaaons as to potential improvements and to provide a control system that stabilizes the existing aircraft for nominal flight and damaged conditions. Towards this several questions are raised and analyses are presented to arrive at answers to some of the questions raised. CART3D, a high-fidelity inviscid analysis package for conceptual and preliminary aerodynamic design, was used to compute a parametric set of solutions over the expected flight domain. Stability and control derivatives were extracted from the database and integrated with the neural flight control system. The Integrated Vehicle Modeling Environment (IVME) was also used for estimating aircraft geometric, inertial, and aerodynamic characteristics. A generic neural flight control system is used to provide adaptive control without the requirement for extensive gain scheduling or explicit system identification. The neural flight control system uses reference models to specify desired handling qualities in the roll, pitch, and yaw axes, and incorporates both pre-trained and on-line learning neural networks in the inverse model portion of the controller. Results are presented for the BEES aircraft in the subsonic regime for terrestrial and Martian environments.

Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep

PubMed Central

2017-01-01

Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways—EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive. PMID:29240764

Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep.

PubMed

Harbison, Susan T; Serrano Negron, Yazmin L; Hansen, Nancy F; Lobell, Amanda S

2017-12-01

Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways-EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive.

Shorter sleep duration and better sleep quality are associated with greater tissue density in the brain.

PubMed

Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Yokoyama, Ryoichi; Kotozaki, Yuka; Nakagawa, Seishu; Sekiguchi, Atsushi; Iizuka, Kunio; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Miyauchi, Carlos Makoto; Shinada, Takamitsu; Sakaki, Kohei; Nozawa, Takayuki; Ikeda, Shigeyuki; Yokota, Susumu; Daniele, Magistro; Sassa, Yuko; Kawashima, Ryuta

2018-04-11

Poor sleep quality is associated with unfavorable psychological measurements, whereas sleep duration has complex relationships with such measurements. The aim of this study was to identify the associations between microstructural properties of the brain and sleep duration/sleep quality in a young adult. The associations between mean diffusivity (MD), a measure of diffusion tensor imaging (DTI), and sleep duration/sleep quality were investigated in a study cohort of 1201 normal young adults. Positive correlations between sleep duration and MD of widespread areas of the brain, including the prefrontal cortex (PFC) and the dopaminergic systems, were identified. Negative correlations between sleep quality and MD of the widespread areas of the brain, including the PFC and the right hippocampus, were also detected. Lower MD has been previously associated with more neural tissues in the brain. Further, shorter sleep duration was associated with greater persistence and executive functioning (lower Stroop interference), whereas good sleep quality was associated with states and traits relevant to positive affects. These results suggest that bad sleep quality and longer sleep duration were associated with aberrant neurocognitive measurements in the brain in healthy young adults.

The role of emotional eating and stress in the influence of short sleep on food consumption.

PubMed

Dweck, Julia S; Jenkins, Steve M; Nolan, Laurence J

2014-01-01

Short sleep duration is associated with elevated body mass index (BMI) and increased energy consumption. The present studies were conducted to determine what role emotional eating and stress might play in these relationships. The first was an exploratory questionnaire study in which sleep quality and duration were measured in conjunction with the Dutch Eating Behavior Questionnaire in 184 women. Emotional and external eating scores were significantly higher in those who reported poor sleep quality (but were not related to sleep duration). In a second study of 64 women who were provided with snacks in the laboratory under stressed and control conditions, elevated food consumption was observed in those who scored high on emotional eating and who reported short sleep (a significant stress × emotional eating × sleep duration interaction) but not in those who reported poor sleep quality. No effects were found in liking or wanting of food and few effects were found on appetite. BMI was not related to sleep duration or sleep quality in either study. The results suggest that the relationship between short sleep and elevated food consumption exists in those who are prone to emotional eating. An external stressor elevated consumption in normal sleepers to the level observed in short sleepers, however, it did not significantly elevate consumption in short sleepers. Future examinations of the effects of sleep duration and quality on food consumption should examine emotional eating status. Copyright © 2013 Elsevier Ltd. All rights reserved.

Short and long sleep duration and risk of drowsy driving and the role of subjective sleep insufficiency.

PubMed

Maia, Querino; Grandner, Michael A; Findley, James; Gurubhagavatula, Indira

2013-10-01

Experimental sleep restriction increases sleepiness and impairs driving performance. However, it is unclear whether short sleep duration in the general population is associated with drowsy driving. The goal of the present study was to evaluate whether individuals in the general population who obtained sleep of 6h or less are more likely to report drowsy driving, and evaluate the role of perceived sleep sufficiency. Data exploring whether subgroups of short sleepers (those who report the most or least unmet sleep need) show different risk profiles for drowsy driving are limited. From the 2009 Behavioral Risk Factor Surveillance System (N=31,522), we obtained the following self-reported data: (1) sleep duration (≤5, 6, 7, 8, 9, or ≥10 h/night); (2) number of days/week of perceived insufficient sleep; (3) among drivers, yes/no response to: "During the past 30 days, have you ever nodded off or fallen asleep, even just for a brief moment, while driving?" (4) demographics, physical/mental health. Using 7 h/night as reference, logistic regression analyses evaluated whether self-reported sleep duration was associated with drowsy driving. Overall, 3.6% reported drowsy driving. Self-identified short-sleepers reported drowsy driving more often, and long sleepers, less often. Among those who perceived sleep as always insufficient, drowsy driving was reported more often when sleep duration was ≤5 h, 6 h, or ≥10 h. Among those who perceived sleep as always sufficient, drowsy driving was reported more often among ≤5 h and 6h sleepers. Overall, drowsy driving was common, particularly in self-identified short-sleepers as a whole, as well as subgroups based on sleep insufficiency. Copyright © 2013 Elsevier Ltd. All rights reserved.

Availability and night-time use of electronic entertainment and communication devices are associated with short sleep duration and obesity among Canadian children.

PubMed

Chahal, H; Fung, C; Kuhle, S; Veugelers, P J

2013-02-01

What is already known about this subject Short sleep duration is a risk factor for obesity. Television (TV) in the bedroom has been shown to be associated with excess body weight in children. Children increasingly use other electronic entertainment and communication devices (EECDs) such as video games, computers, and smart phones. What this study adds Access to and night-time use of EECDs are associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels. Our findings reinforce existing recommendations pertaining to TV and Internet access by the American Academy of Pediatrics and suggest to have these expanded to restricted availability of video games and smart phones in children's bedrooms. While the prevalence of childhood obesity and access to and use of electronic entertainment and communication devices (EECDs) have increased in the past decades, no earlier study has examined their interrelationship. To examine whether night-time access to and use of EECDs are associated with sleep duration, body weights, diet quality, and physical activity of Canadian children. A representative sample of 3398 grade 5 children in Alberta, Canada, was surveyed. The survey included questions on children's lifestyles and health behaviours, the Harvard Youth/Adolescent Food Frequency questionnaire, a validated questionnaire on physical activity, and measurements of heights and weights. Random effect models were used to assess the associations of night-time access to and use of EECDs with sleep, diet quality, physical activity, and body weights. Sixty-four percent of parents reported that their child had access to one or more EECDs in their bedroom. Access to and night-time use of EECDs were associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels in a statistically significant manner. Limiting the availability of EECDs in children's bedrooms and discouraging their

Racial/ethnic disparities in self-reported short sleep duration among US-born and foreign-born adults.

PubMed

Cunningham, Timothy J; Wheaton, Anne G; Ford, Earl S; Croft, Janet B

2016-12-01

Racial/ethnic health disparities are infrequently considered by nativity status in the United States, although the immigrant population has practically doubled since 1990. We investigated the modifying role of nativity status (US- vs. foreign-born) on racial/ethnic disparities in short sleep duration (<7 h), which has serious health consequences. Cross-sectional data from 23,505 US-born and 4,326 foreign-born adults aged ≥ 18 years from the 2012 National Health Interview Survey and multivariable log-linear regression were used to estimate prevalence ratios (PR) for reporting short sleep duration and their corresponding 95% confidence intervals (CI). After controlling for sociodemographic covariates, short sleep was more prevalent among blacks (PR 1.29, 95% CI: 1.21-1.37), Hispanics (PR 1.18, 95% CI: 1.08, 1.29), and Asians (PR 1.37, 95% CI: 1.16-1.61) than whites among US-born adults. Short sleep was more prevalent among blacks (PR 1.71, 95% CI: 1.38, 2.13) and Asians (PR 1.23, 95% CI: 1.02, 1.47) than whites among the foreign-born. Among both US- and foreign-born adults, blacks and Asians had a higher likelihood of short sleep compared to whites. US-born Hispanics, but not foreign-born Hispanics, had a higher likelihood than their white counterparts. Future research should aim to uncover mechanisms underlying these disparities.

A review of an attempt to create shatter cones with magnetic flyer plate technology

NASA Technical Reports Server (NTRS)

Linnerud, H. J.

1981-01-01

The feasibility of creating shatter cones in a controlled laboratory environment is discussed. Magnetic flyer plate technology, which generates high amplitude shock waves in test materials is discribed. Considerable sample shear and break up was observed, however, no shatter cones are found in the tested samples.

Sleep Duration and Age-Related Changes in Brain Structure and Cognitive Performance

PubMed Central

Lo, June C.; Loh, Kep Kee; Zheng, Hui; Sim, Sam K.Y.; Chee, Michael W.L.

2014-01-01

Study Objectives: To investigate the contribution of sleep duration and quality to age-related changes in brain structure and cognitive performance in relatively healthy older adults. Design: Community-based longitudinal brain and cognitive aging study using a convenience sample. Setting: Participants were studied in a research laboratory. Participants: Relatively healthy adults aged 55 y and older at study commencement. Interventions: N/A. Measurements and Results: Participants underwent magnetic resonance imaging and neuropsychological assessment every 2 y. Subjective assessments of sleep duration and quality and blood samples were obtained. Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59% (P = 0.007) and the annual decline rate in global cognitive performance by 0.67% (P = 0.050) in the subsequent 2 y after controlling for the effects of age, sex, education, and body mass index. In contrast, global sleep quality at baseline did not modulate either brain or cognitive aging. High-sensitivity C-reactive protein, a marker of systemic inflammation, showed no correlation with baseline sleep duration, brain structure, or cognitive performance. Conclusions: In healthy older adults, short sleep duration is associated with greater age-related brain atrophy and cognitive decline. These associations are not associated with elevated inflammatory responses among short sleepers. Citation: Lo JC, Loh KK, Zheng H, Sim SK, Chee MW. Sleep duration and age-related changes in brain structure and cognitive performance. SLEEP 2014;37(7):1171-1178. PMID:25061245

Racial/Ethnic Disparities in Short Sleep Duration by Occupation: The Contribution of Immigrant Status

PubMed Central

Jackson, Chandra L.; Hu, Frank B.; Redline, Susan; Williams, David R.; Mattei, Josiemer; Kawachi, Ichiro

2016-01-01

Sleep duration, associated with increased morbidity/mortality, has been shown to vary by race and occupation. Few studies have examined the additional influence of immigrant status. Using a nationally-representative sample of 175,244 US adults from the National Health Interview Survey from 2004-2011, we estimated prevalence ratios (PRs) for short sleep duration (<7 hours/per day) among US- and non-US born Blacks and Latinos by occupation compared to their White counterparts using adjusted Poisson regression models with robust variance. Non-US born participants’ mean age was 46 years, 55% were men, 58% were Latino, and 65% lived in the US ≥15 years. Short sleep prevalence was highest among US- and non-US born Blacks in all occupations, and the prevalence generally increased with increasing professional/management roles in Blacks and Latinos while it decreased among Whites. Adjusted short sleep was more prevalent in US-born Blacks compared to Whites in professional/management (PR=1.52 [95% confidence interval (CI): 1.42-1.63]), support services (PR=1.31 [95% CI: 1.26-1.37]), and laborers (PR=1.11 [95% CI: 1.06-1.16]). The Black-White comparison was even higher for non-US born Black laborers (PR=1.50 [95% CI: 1.24-1.80]). Similar for non-US born Latinos, Latinos born in the US had a higher short sleep prevalence in professional/management (PR=1.14 [95% CI: 1.04-1.24]) and support services (PR=1.06 [95% CI: 1.01-1.11]), but a lower prevalence among laborers (PR=0.77 [95% CI: 0.74-0.81]) compared to Whites. Short sleep varied within and between immigrant status for some ethnicities in particular occupations, further illuminating the need for tailored interventions to address sleep disparities among US workers. PMID:25108693

Modification of Motion Perception and Manual Control Following Short-Durations Spaceflight

NASA Technical Reports Server (NTRS)

Wood, S. J.; Vanya, R. D.; Esteves, J. T.; Rupert, A. H.; Clement, G.

2011-01-01

Adaptive changes during space flight in how the brain integrates vestibular cues with other sensory information can lead to impaired movement coordination and spatial disorientation following G-transitions. This ESA-NASA study was designed to examine both the physiological basis and operational implications for disorientation and tilt-translation disturbances following short-duration spaceflights. The goals of this study were to (1) examine the effects of stimulus frequency on adaptive changes in motion perception during passive tilt and translation motion, (2) quantify decrements in manual control of tilt motion, and (3) evaluate vibrotactile feedback as a sensorimotor countermeasure.

Short-Duration Spaceflight Does Not Prolong QTc Intervals in Male Astronauts

NASA Technical Reports Server (NTRS)

Mitchell, Brett M.; Meck, Janice V.

2004-01-01

Although ventricular dysrhythmias are not increased during, and QTc intervals are not prolonged after, short-duration (5 to 16 days) spaceflights, QTc intervals have not previously been reported during these shorter flights. Holter monitor recordings, obtained in 11 male astronauts who flew on shuttle missions ranging from 5 to 10 days, showed that QTc intervals did not change significantly 10 days before launch, on 2 separate days of spaceflight, and 2 days after landing. Taken together, these data and our previous report show that QTc interval prolongation occurs sometime between the 9th and 30th days of spaceflight.

Will a Short Training Session Improve Multiple-Choice Item-Writing Quality by Dental School Faculty? A Pilot Study.

PubMed

Dellinges, Mark A; Curtis, Donald A

2017-08-01

Faculty members are expected to write high-quality multiple-choice questions (MCQs) in order to accurately assess dental students' achievement. However, most dental school faculty members are not trained to write MCQs. Extensive faculty development programs have been used to help educators write better test items. The aim of this pilot study was to determine if a short workshop would result in improved MCQ item-writing by dental school faculty at one U.S. dental school. A total of 24 dental school faculty members who had previously written MCQs were randomized into a no-intervention group and an intervention group in 2015. Six previously written MCQs were randomly selected from each of the faculty members and given an item quality score. The intervention group participated in a training session of one-hour duration that focused on reviewing standard item-writing guidelines to improve in-house MCQs. The no-intervention group did not receive any training but did receive encouragement and an explanation of why good MCQ writing was important. The faculty members were then asked to revise their previously written questions, and these were given an item quality score. The item quality scores for each faculty member were averaged, and the difference from pre-training to post-training scores was evaluated. The results showed a significant difference between pre-training and post-training MCQ difference scores for the intervention group (p=0.04). This pilot study provides evidence that the training session of short duration was effective in improving the quality of in-house MCQs.

Short sleep duration and longer daytime napping are associated with non-alcoholic fatty liver disease in Chinese adults.

PubMed

Peng, Kui; Lin, Lin; Wang, Zhengyi; Ding, Lin; Huang, Ya; Wang, Po; Xu, Yu; Lu, Jieli; Xu, Min; Bi, Yufang; Wang, Weiqing; Chen, Yuhong; Ning, Guang

2017-09-01

Epidemiologic studies have reported conflicting results on the relationship between short sleep duration and non-alcoholic fatty liver disease (NAFLD). There are no previous studies investigating the effect of daytime napping on NAFLD. In the present study we examined the associations between NAFLD and both nightly sleep duration and daytime napping in a middle-aged and elderly Chinese population. This cross-sectional community-based population study was performed on 8559 individuals aged ≥40 years. Sleep duration and the duration of daytime napping were self-reported using a standardized questionnaire; NAFLD was diagnosed by ultrasonography. In this study sample, the overall prevalence of NAFLD was 30.4%. There was an inverse association between sleep duration and the risk of prevalent NAFLD. In multivariate analysis, the odds ratios (ORs) and 95% confidence intervals (CIs) of prevalent NAFLD for decreasing sleep duration categories (≥9, 8.1-9, 7.1-8, 6.1-7, and ≤6.1 h) were 1.00 (reference), 1.38 (1.13-1.70), 1.32 (1.08-1.61), 1.29 (1.04-1.60), and 1.66 (1.28-2.15), respectively (P trend  = 0.0073). Compared with participants without a daytime napping habit, nap takers with a longer nap duration (>0.5 h) had an increased risk of prevalent NAFLD (OR 1.22; 95% CI 1.06-1.41). The associations of sleep duration and daytime napping duration with NAFLD were generally consistent across different categories of age and obesity, metabolic syndrome, and insulin resistance status. Short sleep duration and longer daytime napping were associated with an increased risk of prevalent NAFLD in a middle-aged and elderly Chinese population. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Respiratory modulation of cardiovascular rhythms before and after short-duration human spaceflight.

PubMed

Verheyden, B; Beckers, F; Couckuyt, K; Liu, J; Aubert, A E

2007-12-01

Astronauts commonly return from space with altered short-term cardiovascular dynamics and blunted baroreflex sensitivity. Although many studies have addressed this issue, post-flight effects on the dynamic circulatory control remain incompletely understood. It is not clear how long the cardiovascular system needs to recover from spaceflight as most post-flight investigations only extended between a few days and 2 weeks. In this study, we examined the effect of short-duration spaceflight (1-2 weeks) on respiratory-mediated cardiovascular rhythms in five cosmonauts. Two paced-breathing protocols at 6 and 12 breaths min(-1) were performed in the standing and supine positions before spaceflight, and after 1 and 25 days upon return. Dynamic baroreflex function was evaluated by transfer function analysis between systolic pressure and the RR intervals. Post-flight orthostatic blood pressure control was preserved in all cosmonauts. In the standing position after spaceflight there was an increase in heart rate (HR) of approx. 20 beats min(-1) or more. Averaged for all five cosmonauts, respiratory sinus dysrhythmia and transfer gain reduced to 40% the day after landing, and had returned to pre-flight levels after 25 days. Low-frequency gain decreased from 6.6 (3.4) [mean (SD)] pre-flight to 3.9 (1.6) post-flight and returned to 5.7 (1.3) ms mmHg(-1) after 25 days upon return to Earth. Unlike alterations in the modulation of HR, blood pressure dynamics were not significantly different between pre- and post-flight sessions. Our results indicate that short-duration spaceflight reduces respiratory modulation of HR and decreases cardiac baroreflex gain without affecting post-flight arterial blood pressure dynamics. Altered respiratory modulation of human autonomic rhythms does not persist until 25 days upon return to Earth.

Effects of stimulus duration and vowel quality in cross-linguistic categorical perception of pitch directions

PubMed Central

Zhu, Yiqing; Wayland, Ratree

2017-01-01

We investigated categorical perception of rising and falling pitch contours by tonal and non-tonal listeners. Specifically, we determined minimum durations needed to perceive both contours and compared to those of production, how stimuli duration affects their perception, whether there is an intrinsic F0 effect, and how first language background, duration, directions of pitch and vowel quality interact with each other. Continua of fundamental frequency on different vowels with 9 duration values were created for identification and discrimination tasks. Less time is generally needed to effectively perceive a pitch direction than to produce it. Overall, tonal listeners’ perception is more categorical than non-tonal listeners. Stimuli duration plays a critical role for both groups, but tonal listeners showed a stronger duration effect, and may benefit more from the extra time in longer stimuli for context-coding, consistent with the multistore model of categorical perception. Within a certain range of semitones, tonal listeners also required shorter stimulus duration to perceive pitch direction changes than non-tonal listeners. Finally, vowel quality plays a limited role and only interacts with duration in perceiving falling pitch directions. These findings further our understanding on models of categorical perception, the relationship between speech perception and production, and the interaction between the perception of tones and vowel quality. PMID:28671991

Short versus long duration infusions of paclitaxel for any advanced adenocarcinoma

PubMed Central

Williams, Chris; Bryant, Andrew

2014-01-01

Background Paclitaxel has become a standard drug used in a number of common cancers. At first long infusions were used to reduce the rate of inflow of the drug and as a result reduce the occurrence of hypersensitivity types of allergic reactions. Trials with shorter durations of infusion, and using a cocktail of anti-allergic drugs to prevent hypersensitivity reactions, some randomised, were begun. These were interpreted as showing that effectiveness of treatment was not lessened by a short infusion time. These studies also appeared to show that some important toxicities were less common with short infusions and that they were more convenient for the patient and the hospital. Objectives To assess the effectiveness and toxicity of short versus long infusions of paclitaxel for any advanced adenocarcinoma. Search methods We searched the Cochrane Gynaecological Cancer Review Group Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) Issue 1, 2009, MEDLINE and EMBASE up to March 2009. We also searched registers of clinical trials, abstracts of scientific meetings, reference lists of included trials and contacted experts in the field, as well as drug companies. Selection criteria The review was restricted to randomised controlled trials (RCTs) of single agent paclitaxel or paclitaxel with other drugs, where the only variable was the duration of paclitaxel infusion. The review only includes patients with advanced adenocarcinoma. Data collection and analysis Two review authors independently abstracted data and assessed risk of bias. Where possible the data were synthesised in meta-analyses. Main results We identified six trials that met our inclusion criteria. The trials compared 3, 24 and 96 hour infusions and one trial examined different schedules (1 versus 3 day). From the included RCTs we found no evidence of a difference between short and long infusions in terms of overall and progression-free survival and tumour non-response. In most

Influence of Customer Quality Perception on the Effectiveness of Commercial Stimuli for Electronic Products.

PubMed

Garrido-Morgado, Álvaro; González-Benito, Óscar; Martos-Partal, Mercedes

2016-01-01

Creating and maintaining customer loyalty are strategic requirements for modern business. In the current competitive context, product quality, and brand experience are crucial in building and maintaining customer loyalty. Consumer loyalty, which may be classified into cognitive loyalty and affective loyalty, is related to customers' quality perception. Cue utilization theory distinguishes two dimensions for perceived quality, extrinsic quality-linked to the brand-and intrinsic quality-related with internal product characteristics. We propose that (i) cognitive loyalty is more influenced by intrinsic product quality whereas extrinsic product quality (brand name) is more salient for affective loyalty and, (ii) different commercial stimuli have a differential effectiveness on intrinsic and extrinsic perceived quality. In fact, in this study, we analyze how perceived quality dimensions may influence the effectiveness of two different commercial stimuli: displays and advertising flyers. While displays work within the point of sale under time-constrained conditions where consumers are more likely to use heuristics to simplify their decisions, advertising flyers work outside of the point of sale under low time-constrained conditions, and therefore favor a more reasoned purchase decision where systematic processing will be more likely. We analyze the role of quality perception in determining the effectiveness of both these commercial stimuli for selling products that induce high purchase involvement and perceived risk. The empirical analysis focuses on computer products sold by one of Europe's largest computer retailers and it combines scanner, observational, and survey data. The results show that both dimensions of quality perceptions moderate the influence of displays and advertising flyers on sales, but their impact is different on each commercial stimuli. Extrinsic quality perception increases to a greater extent the effect of displays due to the use of a brand name

The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle

NASA Technical Reports Server (NTRS)

1996-01-01

STS-77 ESC VIEW --- The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). The free-flyer was re-captured by the six crew members on May 21, 1996. The crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:51:29.

Injury tolerance criteria for short-duration axial impulse loading of the isolated tibia.

PubMed

Quenneville, Cheryl E; McLachlin, Stewart D; Greeley, Gillian S; Dunning, Cynthia E

2011-01-01

Impulse loading of the lower leg during events such as ejection seat landings or in-vehicle land mine blasts may result in devastating injuries. These impacts achieve higher forces over shorter durations than car crashes, from which experimental results have formed the current basis for protective measures of an axial force limit of 5.4 kN, as registered by an anthropomorphic test device (ATD). The hypotheses of this study were that the injury tolerance of the isolated tibia to short-duration axial loading is higher than that previously reported and that secondary parameters such as momentum or kinetic energy are significant for fracture tolerance, in addition to force. Seven pairs of cadaveric tibias were impacted using a pneumatic testing apparatus, replicating short-duration axial impulse events. One specimen from each pair was impacted with a light mass and the contralateral impacted with a heavy mass, to investigate the effects of momentum and kinetic energy, as well as force, on injury. Impacts were applied incrementally until failure. Force, kinetic energy, age, and height were shown to be significant factors in the probability of fracture. A 10% risk of injury corresponded to an impact force of 7.9 kN, with an average kinetic energy of 240 J. In comparison, this same impact level applied to an ATD would register a force of 16.2 kN because of the higher stiffness of the ATD. These results suggest that the current injury standard may be too conservative for the tibia during high-speed impacts such as in-vehicle land mine blasts and that factors in addition to force should be taken into consideration.

Working multiple jobs over a day or a week: Short-term effects on sleep duration

PubMed Central

Marucci-Wellman, Helen R.; Lombardi, David A.; Willetts, Joanna L.

2016-01-01

ABSTRACT Approximately 10% of the employed population in the United States works in multiple jobs. They are more likely to work long hours and in nonstandard work schedules, factors known to impact sleep duration and quality, and increase the risk of injury. In this study we used multivariate regression models to compare the duration of sleep in a 24-hour period between workers working in multiple jobs (MJHs) with single job holders (SJHs) controlling for other work schedule and demographic factors. We used data from the Bureau of Labor Statistics US American Time Use Survey (ATUS) pooled over a 9-year period (2003–2011). We found that MJHs had significantly reduced sleep duration compared with SJHs due to a number of independent factors, such as working longer hours and more often late at night. Male MJHs, working in their primary job or more than one job on the diary day, also had significantly shorter sleep durations (up to 40 minutes less on a weekend day) than male SJHs, even after controlling for all other factors. Therefore, duration of work hours, time of day working and duration of travel for work may not be the only factors to consider when understanding if male MJHs are able to fit in enough recuperative rest from their busy schedule. Work at night had the greatest impact on sleep duration for females, reducing sleep time by almost an hour compared with females who did not work at night. We also hypothesize that the high frequency or fragmentation of non-leisure activities (e.g. work and travel for work) throughout the day and between jobs may have an additional impact on the duration and quality of sleep for MJHs. PMID:27092404

Working multiple jobs over a day or a week: Short-term effects on sleep duration.

PubMed

Marucci-Wellman, Helen R; Lombardi, David A; Willetts, Joanna L

Approximately 10% of the employed population in the United States works in multiple jobs. They are more likely to work long hours and in nonstandard work schedules, factors known to impact sleep duration and quality, and increase the risk of injury. In this study we used multivariate regression models to compare the duration of sleep in a 24-hour period between workers working in multiple jobs (MJHs) with single job holders (SJHs) controlling for other work schedule and demographic factors. We used data from the Bureau of Labor Statistics US American Time Use Survey (ATUS) pooled over a 9-year period (2003-2011). We found that MJHs had significantly reduced sleep duration compared with SJHs due to a number of independent factors, such as working longer hours and more often late at night. Male MJHs, working in their primary job or more than one job on the diary day, also had significantly shorter sleep durations (up to 40 minutes less on a weekend day) than male SJHs, even after controlling for all other factors. Therefore, duration of work hours, time of day working and duration of travel for work may not be the only factors to consider when understanding if male MJHs are able to fit in enough recuperative rest from their busy schedule. Work at night had the greatest impact on sleep duration for females, reducing sleep time by almost an hour compared with females who did not work at night. We also hypothesize that the high frequency or fragmentation of non-leisure activities (e.g. work and travel for work) throughout the day and between jobs may have an additional impact on the duration and quality of sleep for MJHs.

Short Durations of Static Stretching when Combined with Dynamic Stretching do not Impair Repeated Sprints and Agility

PubMed Central

Wong, Del P.; Chaouachi, Anis; Lau, Patrick W.C.; Behm, David G.

2011-01-01

This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA) and change of direction (COD). Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s). Three dynamic stretching exercises of 30 s duration were then performed (90 s total). Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. Key points The duration of combined static and dynamic stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit and reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). No significant differences in RSA and COD between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. The short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. PMID:24149890

Short Sleep Duration Is Associated With Eating More Carbohydrates and Less Dietary Fat in Mexican American Children.

PubMed

Martinez, Suzanna M; Tschann, Jeanne M; Butte, Nancy F; Gregorich, Steve E; Penilla, Carlos; Flores, Elena; Greenspan, Louise C; Pasch, Lauri A; Deardorff, Julianna

2017-02-01

Short sleep duration is a risk factor for childhood obesity. Mechanisms are unclear, but may involve selection of high carbohydrate foods. This study examined the association between estimated sleep duration and macronutrient intake as percentages of total energy among Mexican American (MA) 9-11 year olds. This cross-sectional study measured diet using two 24-hour recalls and estimated sleep duration using hip-worn accelerometry in MA children (n = 247) who were part of a cohort study. Child and maternal anthropometry were obtained; mothers reported on demographic information. Using linear regression, we examined the relationship of sleep duration with energy intake, sugar intake, and the percentage of energy intake from carbohydrates, fat, and protein. Children were 47% male; mean age was 10 (SD = 0.9) years. Mean sleep duration was 9.6 (SD = 0.8) hours; 53% were overweight/obese, with a mean energy intake of 1759 (SD = 514) calories. Longer sleep duration was independently associated with a lower percentage of energy intake from carbohydrates (β = -0.22, p < .01) and a higher percentage of energy from fat (β = 0.19, p < .01), driven by the percentage of energy from polyunsaturated fatty acids (PUFA; β = 0.17, p < .05). No association was found with the intake of energy or total sugars, or the percent of calories from protein. MA children who slept longer consumed diets with a lower percentage of calories from carbohydrates and a higher percentage from fat, especially from PUFA. Short sleep duration may be a risk factor for food cravings that are high in carbohydrate content and may displace heart-healthy dietary fat, and thereby increase obesity risk among children. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Short Durations of Static Stretching when Combined with Dynamic Stretching do not Impair Repeated Sprints and Agility.

PubMed

Wong, Del P; Chaouachi, Anis; Lau, Patrick W C; Behm, David G

2011-01-01

This study aimed to compare the effect of different static stretching durations followed by dynamic stretching on repeated sprint ability (RSA) and change of direction (COD). Twenty-five participants performed the RSA and COD tests in a randomized order. After a 5 min aerobic warm up, participants performed one of the three static stretching protocols of 30 s, 60 s or 90 s total duration (3 stretches x 10 s, 20 s or 30 s). Three dynamic stretching exercises of 30 s duration were then performed (90 s total). Sit-and-reach flexibility tests were conducted before the aerobic warm up, after the combined static and dynamic stretching, and post- RSA/COD test. The duration of static stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit-and-reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001). However there were no significant differences in RSA and COD performance between the 3 stretching conditions. The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects. Furthermore, the short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments. Key pointsThe duration of combined static and dynamic stretching had a positive effect on flexibility with 36.3% and 85.6% greater sit and reach scores with the 60 s and 90 s static stretching conditions respectively than with the 30 s condition (p ≤ 0.001).No significant differences in RSA and COD between the 3 stretching conditions.The lack of change in RSA and COD might be attributed to a counterbalancing of static and dynamic stretching effects.The short duration (≤ 90 s) static stretching may not have provided sufficient stimulus to elicit performance impairments.

A comparison of romifidine and xylazine when used with diazepam/ketamine for short duration anesthesia in the horse.

PubMed Central

Kerr, C L; McDonell, W N; Young, S S

1996-01-01

The purpose of this study was to compare and evaluate sedation with intravenous xylazine (1.1 mg/kg bodyweight [BW]) versus intravenous romifidine (100 micrograms/kg BW) followed by induction of anesthesia with intravenous diazepam (0.04 mg/kg BW) and ketamine (2.2 mg/kg BW). Twelve healthy horses were used in a blinded, randomized, cross-over design. Heart rate, presence of 2nd degree atrioventricular heart blocks (2 degrees AVB), respiratory rate, arterial blood pressures, blood gases, packed cell volume, total serum proteins, and duration of anesthesia and recumbency were recorded. Induction and recovery quality was evaluated using a 0 to 4 score. Response to stimulation with noise, pressure, and cutaneous electrical stimulation was assessed at 5 minute intervals during recumbency to evaluate the depth of anesthesia. Heart rate was lower and 2 degrees AVB more frequent in the romifidine group, while blood pressure was lower in the xylazine group. Duration of anesthesia was longer in the romifidine group (mean 20.8, s mean 2.3 min) versus the xylazine group (mean 15.8, s mean 1.6 min), while induction and recovery were excellent in both groups. Respiratory rates, blood gas values, packed cell volumes, and total protein levels did not differ between groups. The results indicate that romifidine premedication followed by diazepam and ketamine is a very satisfactory regime for short duration intravenous anesthesia in horses. PMID:8896874

Dynamics Questions Associated with the AERCam Sprint Free-Flyer

NASA Technical Reports Server (NTRS)

Williams, Trevor

1997-01-01

The International Space Station will require the development of small robotic vehicles for such tasks as external inspection, monitoring of extravehicular activities (EVA's) and station build-up, and providing additional lighting at EVA worksites. The Autonomous EVA Robotic Camera (AERCam) family of free-flyers is currently being developed at NASA Johnson Space Center to perform these functions; the first member of the family is the AERCam Sprint vehicle. Many interesting dynamical questions are associated with the Sprint free-flyer. For instance, the reaction of a vehicle which is nearly spherically symmetric (such as Sprint) to a stuck-on thruster is significantly more complicated than that obtained for an idealized, perfectly spherical, spacecraft model. In particular, the real spacecraft will experience a form of forced nutation, with convergence towards either its major or minor principal axis, depending on both the applied torque and the mass properties of the vehicle. Furthermore, the body-fixed jet force vector may have a significant component along this principal axis, so giving rise to a considerable net linear acceleration of the spacecraft. The large velocity that can result is very important, as it may lead to collision with the nearby Orbiter, and is completely overlooked in the idealized analysis. This report will firstly briefly describe the stuck-on thruster dynamics of the real vehicle, and outline how the small products of inertia of the spacecraft determine the time constants of the motion. Secondly, the dynamical effects of a failed-off jet on the Sprint free-flyer will be described in more detail, and compared with the stuck-on thruster case. This will help to show whether the two malfunctions should be dealt with differently in flight. Finally, the stuck-on thruster detection software (known as the uncommanded motion algorithm) that is proposed to be flown on the Sprint vehicle will be analyzed, and all possible perturbation sources that may

The within-person association between alcohol use and sleep duration and quality in situ: An experience sampling study

PubMed Central

Lydon, David M.; Ram, Nilam; Conroy, David E.; Pincus, Aaron L.; Geier, Charles F.; Maggs, Jennifer L.

2016-01-01

Objective Despite evidence for detrimental effects of alcohol on sleep quality in laboratory studies, alcohol is commonly used as a self-prescribed sleep aid. This study examined the within-person associations of alcohol use with sleep duration and quality in everyday life to gain insight into the ecological validity of laboratory findings on the association between sleep and alcohol. Method A sample of 150 adults (age 19–89 years) were followed for 60+ days as part of an intensive experience sampling study wherein participants provided daily reports of their alcohol use, sleep duration, and sleep quality. Within-person and between-person associations of daily sleep duration and quality with alcohol use were examined using multilevel models. Results A significant, negative within-person association was observed between sleep quality and alcohol use. Sleep quality was lower on nights following alcohol use. Sleep duration did not vary as a function of within-person variation in alcohol use. Conclusions In line with laboratory assessments, alcohol use was associated with low sleep quality but was not associated with sleep duration, suggesting that laboratory findings generalize to everyday life. This examination of individuals’ daily lives suggests that alcohol does not systematically improve sleep quality or duration in real life. PMID:27249804

Sleep duration and cardiometabolic risk: a review of the epidemiologic evidence.

PubMed

Knutson, Kristen L

2010-10-01

Laboratory studies have found that short-term sleep restriction is associated with impairments in glucose metabolism, appetite regulation and blood pressure regulation. This chapter reviews the epidemiologic evidence for an association between habitual sleep duration and quality and risk of cardiometabolic diseases including obesity, diabetes and hypertension. Multiple studies observed a cross-sectional association between short sleep duration (generally <6 h per night) and increased body mass index or obesity, prevalent diabetes and prevalent hypertension. Many studies also reported an association between self-reported long sleep duration (generally >8 h per night) and cardiometabolic disease. There have been a few prospective studies and several, but not all, have found an association between short sleep and incident diabetes, hypertension and markers of cardiovascular disease. Future prospective epidemiologic studies need to include objective measures of sleep, and intervention studies are needed in order to establish a causal link between impaired or insufficient sleep and cardiometabolic disease risk. Copyright © 2010 Elsevier Ltd. All rights reserved.

Projected changes to short- and long-duration precipitation extremes over the Canadian Prairie Provinces

NASA Astrophysics Data System (ADS)

Masud, M. B.; Khaliq, M. N.; Wheater, H. S.

2017-09-01

The effects of climate change on April-October short- and long-duration precipitation extremes over the Canadian Prairie Provinces were evaluated using a multi-Regional Climate Model (RCM) ensemble available through the North American Regional Climate Change Assessment Program. Simulations considered include those performed with six RCMs driven by the National Centre for Environmental Prediction (NCEP) reanalysis II product for the 1981-2000 period and those driven by four Atmosphere-Ocean General Circulation Models (AOGCMs) for the current 1971-2000 and future 2041-2070 periods (i.e. a total of 11 current-to-future period simulation pairs). A regional frequency analysis approach was used to develop 2-, 5-, 10-, 25-, and 50-year return values of precipitation extremes from NCEP and AOGCM-driven current and future period simulations that respectively were used to study the performance of RCMs and projected changes for selected return values at regional, grid-cell and local scales. Performance errors due to internal dynamics and physics of RCMs studied for the 1981-2000 period reveal considerable variation in the performance of the RCMs. However, the performance errors were found to be much smaller for RCM ensemble averages than for individual RCMs. Projected changes in future climate to selected regional return values of short-duration (e.g. 15- and 30-min) precipitation extremes and for longer return periods (e.g. 50-year) were found to be mostly larger than those to the longer duration (e.g. 24- and 48-h) extremes and short return periods (e.g. 2-year). Overall, projected changes in precipitation extremes were larger for southeastern regions followed by southern and northern regions and smaller for southwestern and western regions of the study area. The changes to return values were also found to be statistically significant for the majority of the RCM-AOGCM simulation pairs. These projections might be useful as a key input for the future planning of urban

Discrimination of short-duration (two-pulse) flashes as a function of signal luminance and method of measurement.

DOT National Transportation Integrated Search

1971-11-01

The recent introduction of strobe lights for anticollision purposes raises the possibility of using temporal patterns of short duration flashes as information carrying signals. The current experiments are concerned with the detection of the minimum d...

The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle

NASA Technical Reports Server (NTRS)

1996-01-01

STS-77 ESC VIEW --- The Spartan 207 free-flyer is held in a low-hover mode above its berth in the Space Shuttle Endeavour's cargo bay in the grasp of the Remote Manipulator System (RMS). The Spacehab module can be seen in the foreground. The free-flyer was re-captured by the six crew members on May 21, 1996. The crew has spent a portion of the early stages of the mission in various activities involving the Spartan 207 and the related Inflatable Antenna Experiment (IAE). The Spartan project is managed by NASA's Goddard Space Flight Center (GSFC) for NASA's Office of Space Science, Washington, D.C. GMT: 09:51:50.

Short sleep duration is associated with B-type natriuretic peptide levels and predicts the death of Japanese patients with type 2 diabetes.

PubMed

Hamasaki, Hidetaka; Katsuyama, Hisayuki; Sako, Akahito; Yanai, Hidekatsu

2017-08-01

To investigate the associations of sleep duration with all-cause mortality, glycemic control, and other clinical parameters of patients with type 2 diabetes. From April 2013 to December 2015, we conducted a retrospective cohort study. Study participants were divided into three groups according to their sleep duration. Multiple regression analysis and Cox proportional hazards analysis were performed to assess the independent associations of sleep duration with clinical parameters and all-cause mortality. We enrolled 1233 patients who were then followed for 860 ± 264 days. During the follow-up period, 20 patients (1.6%) died. Sleep duration inversely associated with plasma B-type natriuretic peptide levels (β = -0.203, p = 0.012) in short (<7 h) sleepers, whereas it was positively associated with hemoglobin A1c levels (β = 0.156, p = 0.021) in long (≥9 h) sleepers. Moreover, Cox proportional hazard analysis revealed that short sleep duration was a significant predictor of all-cause mortality (hazard ratio = 0.473; confidence interval 0.248-0.905, p = 0.024). Short sleep duration may serve as a prognostic indicator of mortality in Japanese patients with type 2 diabetes and may increase cardiovascular stress. Adequate sleep is essential for the management of type 2 diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of elevation on extreme precipitation of short durations: evidences of orographic signature on the parameters of Depth-Duration-Frequency curves

NASA Astrophysics Data System (ADS)

Avanzi, Francesco; De Michele, Carlo; Gabriele, Salvatore; Ghezzi, Antonio; Rosso, Renzo

2015-04-01

Here, we show how atmospheric circulation and topography rule the variability of depth-duration-frequency (DDF) curves parameters, and we discuss how this variability has physical implications on the formation of extreme precipitations at high elevations. A DDF is a curve ruling the value of the maximum annual precipitation H as a function of duration D and the level of probability F. We consider around 1500 stations over the Italian territory, with at least 20 years of data of maximum annual precipitation depth at different durations. We estimated the DDF parameters at each location by using the asymptotic distribution of extreme values, i.e. the so-called Generalized Extreme Value (GEV) distribution, and considering a statistical simple scale invariance hypothesis. Consequently, a DDF curve depends on five different parameters. A first set relates H with the duration (namely, the mean value of annual maximum precipitation depth for unit duration and the scaling exponent), while a second set links H to F (namely, a scale, position and shape parameter). The value of the shape parameter has consequences on the type of random variable (unbounded, upper or lower bounded). This extensive analysis shows that the variability of the mean value of annual maximum precipitation depth for unit duration obeys to the coupled effect of topography and modal direction of moisture flux during extreme events. Median values of this parameter decrease with elevation. We called this phenomenon "reverse orographic effect" on extreme precipitation of short durations, since it is in contrast with general knowledge about the orographic effect on mean precipitation. Moreover, the scaling exponent is mainly driven by topography alone (with increasing values of this parameter at increasing elevations). Therefore, the quantiles of H(D,F) at durations greater than unit turn to be more variable at high elevations than at low elevations. Additionally, the analysis of the variability of the shape

Cortical and subcortical processing of short duration speech stimuli in trained rock musicians: a pilot study.

PubMed

Kumar, Prawin; Anil, Sam Publius; Grover, Vibhu; Sanju, Himanshu Kumar; Sinha, Sachchidanand

2017-02-01

Most trained musicians are actively involved in rigorous practice from several years to achieve a high level of proficiency. Therefore, musicians are best group to research changes or modification in brain structures and functions across several information processing systems. This study aimed to investigate cortical and subcortical processing of short duration speech stimuli in trained rock musicians and non-musicians. Two groups of participant (experimental and control groups) in the age range of 18-25 years were selected for the study. Experimental group includes 15 rock musicians who had minimum professional training of 5 years of rock music, and each member had to be a regular performer of rock music for at least 15 h a week. Further age-matched 15 participants who were not having any formal training of any music served as non-musicians, in the control group. The speech-evoked ABR (S-ABR) and speech-evoked ALLR (S-LLR) with short duration speech 'synthetic /da/' was elicited in both groups. Different measures were analyzed for S-ABR and S-LLR. For S-ABR, MANOVA revealed significant main effect of groups on latencies of wave V, wave A, and amplitude of wave V/A slope. Similarly, Kruskal-Wallis test showed significantly higher F 0 amplitude in rock musicians compared with non-musicians. For S-LLR, MANOVA showed statistically significant differences observed for latencies of wave P2 and N2 and amplitude measures of P2-N2 amplitude. This study indicated better neural processing of short duration speech stimuli at subcortical as well as cortical level among rock musicians when compared with non-musicians.

The measurement of intracranial pressure and brain displacement due to short-duration dynamic overpressure loading

NASA Astrophysics Data System (ADS)

Iwaskiw, A. S.; Ott, K. A.; Armiger, R. S.; Wickwire, A. C.; Alphonse, V. D.; Voo, L. M.; Carneal, C. M.; Merkle, A. C.

2018-01-01

The experimental measurement of biomechanical responses that correlate with blast-induced traumatic brain injury (bTBI) has proven challenging. These data are critical for both the development and validation of computational and physical head models, which are used to quantify the biomechanical response to blast as well as to assess fidelity of injury mitigation strategies, such as personal protective equipment. Therefore, foundational postmortem human surrogate (PMHS) experimental data capturing the biomechanical response are necessary for human model development. Prior studies have measured short-duration pressure transmission to the brain (Kinetic phase), but have failed to reproduce and measure the longer-duration inertial loading that can occur (Kinematic phase). Four fully instrumented PMHS were subjected to short-duration dynamic overpressure in front-facing and rear-facing orientations, where intracranial pressure (ICP), global head kinematics, and brain motion (as measured by high-speed X-ray) with respect to the skull were recorded. Peak ICP results generally increased with increased dose, and a mirrored pressure response was seen when comparing the polarity of frontal bone versus occipital bone ICP sensors. The head kinematics were delayed when compared to the pressure response and showed higher peak angles for front-facing tests as compared to rear-facing. Brain displacements were approximately 2-6 mm, and magnitudes did not change appreciably between front- and rear-facing tests. These data will be used to inform and validate models used to assess bTBI.

Effect of active warm-up duration on morning short-term maximal performance during Ramadan.

PubMed

Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar

2015-01-01

Purpose To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Methods Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Results Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. Conclusions There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning.

Effect of active warm-up duration on morning short-term maximal performance during Ramadan.

PubMed

Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar

2015-01-01

To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning.

Effect of active warm-up duration on morning short-term maximal performance during Ramadan

PubMed Central

Baklouti, Hana; Chtourou, Hamdi; Aloui, Asma; Chaouachi, Anis; Souissi, Nizar

2015-01-01

Purpose To examine the effect of active warm-up duration on short-term maximal performance assessed during Ramadan in the morning. Methods Twelve healthy active men performed four Wingate tests for measurement of peak power and mean power before and during Ramadan at 09:00 a.m. The tests were performed on separate days, after either a 5-min or a 15-min warm-up. The warm-up consisted in pedaling at 50% of the power output obtained at the last stage of a submaximal multistage cycling test. Oral temperature was measured at rest and after warming-up. Furthermore, ratings of perceived exertion were obtained immediately after the Wingate test. Results Oral temperature was higher after the 15-min warm-up than the 5-min warm-up throughout the study. Moreover, peak power and mean power were higher after the 15-min warm-up than the 5-min warm-up before Ramadan. However, during Ramadan, there was no significant difference between the two warm-up durations. In addition, ratings of perceived exertion were higher after the 15-min warm-up than the 5-min warm-up only during Ramadan. Conclusions There is no need to prolong the warm-up period before short-term maximal exercise performed during Ramadan in the morning. PMID:25676856

Mediterranean Diet and Changes in Sleep Duration and Indicators of Sleep Quality in Older Adults.

PubMed

Campanini, Marcela Z; Guallar-Castillón, Pilar; Rodríguez-Artalejo, Fernando; Lopez-Garcia, Esther

2017-03-01

To examine the association between adherence to a Mediterranean diet (MD) and changes in sleep duration and sleep quality in older adults. We used data from 1596 participants in the Seniors-ENRICA cohort aged ≥ 60 years. MD was evaluated in 2012 with the Mediterranean Diet Adherence Screener (MEDAS) score. Sleep duration (h) and indicators of poor sleep quality were assessed both in 2012 and 2015. Analyses were adjusted for sociodemographic, lifestyle and morbidity variables, and for sleep duration and the number of poor sleep indicators at baseline. Over a median follow-up of 2.8 years, 12.2% of individuals increased and 8.8% decreased their sleep duration by ≥2 h/night. Compared with those in the lowest tertile of adherence to the MD in 2012, those in the highest tertile showed both a lower risk of a ≥2 h/night increase in sleep duration (odds ratio [OR]: 0.54, 95% confidence interval [CI] 0.34-0.85, p-trend = .01) and of a ≥2 h/night decrease (OR: 0.58, 95% CI 0.35-0.95, p-trend = 0.02) from 2012 to 2015. Being in the highest tertile of MD in 2012 was also associated with lower risk of poor sleep quality at follow-up, the OR (95% CI) for having 2-3 indicators of poor sleep was 0.70 (0.51-0.97) and for ≥4 indicators was 0.68 (0.47-0.99, p-trend = .04). High adherence to the MD was also associated with 56% lower odds of having large changes in sleep duration and ≥2 indicators of poor sleep quality simultaneously (OR: 0.44, 95% CI 0.29-0.68, p trend < .001). Adherence to a MD pattern was associated with lower risk of changes in sleep duration and with better sleep quality in older adults. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Sleep duration and quality, and risk of gestational diabetes mellitus in pregnant Chinese women.

PubMed

Wang, H; Leng, J; Li, W; Wang, L; Zhang, C; Li, W; Liu, H; Zhang, S; Chan, J; Hu, G; Yu, Z; Yang, X

2017-01-01

To examine the association between sleep disturbances during pregnancy and risk of gestational diabetes mellitus. From 2010 to 2012, 12 506 women in Tianjin, China, were screened using a 50-g 1-h glucose challenge test at 24-28 weeks' gestation. Those with glucose challenge test values of ≥ 7.8 mmol/l were invited to further undergo a 75-g 2-h oral glucose tolerance test. Gestational diabetes was determined according to the International Association of Diabetes and Pregnancy Study Group's definition. Self-reported sleep duration and sleep quality during pregnancy was documented using a modified questionnaire. Logistic regression was used to obtain odds ratios and 95% CIs. A total of 919 women (7.3%) had gestational diabetes. Sleep duration was found to have an approximate J-shaped association with gestational diabetes risk after adjusting for covariates. Compared with a sleep duration of 7-9 h/day (43% of 12 506 women), the adjusted odds ratios for sleep duration of ≥ 9 h/day (55%) and < 7 h/day (2%) for gestational diabetes were 1.21 (95% CI 1.03-1.42) and 1.36 (95% CI 0.87-2.14), respectively. Compared with good sleep quality (37.9% of 12 506 women), the adjusted odds ratios of moderate (59.9%) and poor sleep quality (2.2%) for gestational diabetes were 1.19 (95% CI 1.01-1.41) and 1.61 (95% CI 1.04-2.50), respectively. In pregnant Chinese women, poor sleep quality, and shorter and longer duration of sleep during pregnancy were independently associated with an increased risk of gestational diabetes. © 2016 Diabetes UK.

Short-duration electrical immobilization of lake trout

USGS Publications Warehouse

Gaikowski, Mark P.; Gingerich, William H.; Gutreuter, Steve

2001-01-01

Chemical anesthetics induce stress responses, and most leave residues in fish tissues that require a certain withdrawal time before the animal can be released into the environment. Therefore, alternatives are needed in cases when fish must be released immediately, for example, during egg-collecting operations or after implanting elastomer tags. To evaluate pulsed direct current as an alternative method of immobilization, individual lake trout Salvelinus namaycush were electrically immobilized using various pulsed-DC voltage gradients and shock durations. Duration of opercular recovery and narcosis were measured for individual fish. Fish were euthanized 24 h after electrical immobilization and processed for lateral radiograph analysis and assessment of perivertebral hemorrhaging by dissection. Survival of lake trout after electrical immobilization at 0.6 V/cm for 30 or 40 s or 0.8 V/cm for 5 or 15 s was monitored for 81 or 84 d after immobilization. Mean narcosis duration increased with voltage gradient and shock duration. Larger fish had longer periods of narcosis at the same combination of voltage gradient and shock duration. Radiological evaluation indicated that 9 of 28 fish in the oldest age-class tested had detectable injuries of the vertebral column, but all but one were in the lowest injury category. Although vertebral column injuries were observed in most small fish, the majority of vertebral column injuries were minor compressions involving two to seven vertebrae. Of the 82 lake trout electrically immobilized to assess long-term survival, only 5 died (6%). Our data suggest that lake trout could be electrically immobilized for a sufficient period to allow field workers to collect length and weight data and implant visible implant tags or colored elastomer tags. The technique we used, however, is probably not appropriate for procedures that require immobilization for more than 2a??3 min.

Influence of Customer Quality Perception on the Effectiveness of Commercial Stimuli for Electronic Products

PubMed Central

Garrido-Morgado, Álvaro; González-Benito, Óscar; Martos-Partal, Mercedes

2016-01-01

Creating and maintaining customer loyalty are strategic requirements for modern business. In the current competitive context, product quality, and brand experience are crucial in building and maintaining customer loyalty. Consumer loyalty, which may be classified into cognitive loyalty and affective loyalty, is related to customers' quality perception. Cue utilization theory distinguishes two dimensions for perceived quality, extrinsic quality—linked to the brand—and intrinsic quality—related with internal product characteristics. We propose that (i) cognitive loyalty is more influenced by intrinsic product quality whereas extrinsic product quality (brand name) is more salient for affective loyalty and, (ii) different commercial stimuli have a differential effectiveness on intrinsic and extrinsic perceived quality. In fact, in this study, we analyze how perceived quality dimensions may influence the effectiveness of two different commercial stimuli: displays and advertising flyers. While displays work within the point of sale under time-constrained conditions where consumers are more likely to use heuristics to simplify their decisions, advertising flyers work outside of the point of sale under low time-constrained conditions, and therefore favor a more reasoned purchase decision where systematic processing will be more likely. We analyze the role of quality perception in determining the effectiveness of both these commercial stimuli for selling products that induce high purchase involvement and perceived risk. The empirical analysis focuses on computer products sold by one of Europe's largest computer retailers and it combines scanner, observational, and survey data. The results show that both dimensions of quality perceptions moderate the influence of displays and advertising flyers on sales, but their impact is different on each commercial stimuli. Extrinsic quality perception increases to a greater extent the effect of displays due to the use of a brand

Immune System Dysregulation, Viral Reactivation and Stress During Short-Duration Space Flight

NASA Technical Reports Server (NTRS)

Crucian, Brian; Mehta, Satish; Stowe, Raymond; Uchakin, Peter; Quiriarte, Heather; Pierson, Duane; Sams, Clarence

2010-01-01

This slide presentation reviews a study that was conducted to ascertain if the immune system dysregulation, viral reactivation and stress from short duration space flight were a result of the stress of landing and readjustment to gravity. The objectives of the study were to replace several recent immune studies with one comprehensive study that will include in-flight sampling; address lack of in-flight data: (i.e., determine the in-flight status of immunity, physiological stress, viral immunity/reactivation); determine the clinical risk related to immune dysregulation for exploration class spaceflight; and determine the appropriate monitoring strategy for spaceflight-associated immune dysfunction, that could be used for the evaluation of countermeasures.

Ice Roughness in Short Duration SLD Icing Events

NASA Technical Reports Server (NTRS)

McClain, Stephen T.; Reed, Dana; Vargas, Mario; Kreeger, Richard E.; Tsao, Jen-Ching

2014-01-01

Ice accretion codes depend on models of roughness parameters to account for the enhanced heat transfer during the ice accretion process. While mitigating supercooled large droplet (SLD or Appendix O) icing is a significant concern for manufacturers seeking future vehicle certification due to the pending regulation, historical ice roughness studies have been performed using Appendix C icing clouds which exhibit mean volumetric diameters (MVD) much smaller than SLD clouds. Further, the historical studies of roughness focused on extracting parametric representations of ice roughness using multiple images of roughness elements. In this study, the ice roughness developed on a 21-in. NACA 0012 at 0deg angle of attack exposed to short duration SLD icing events was measured in the Icing Research Tunnel at the NASA Glenn Research Center. The MVD's used in the study ranged from 100 micrometer to 200 micrometers, in a 67 m/s flow, with liquid water contents of either 0.6 gm/cubic meters or 0.75 gm/cubic meters. The ice surfaces were measured using a Romer Absolute Arm laser scanning system. The roughness associated with each surface point cloud was measured using the two-dimensional self-organizing map approach developed by McClain and Kreeger (2013) resulting in statistical descriptions of the ice roughness.

Modeling HCV cure after an ultra-short duration of therapy with direct acting agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goyal, Ashish; Lurie, Yoav; Meissner, Eric G.

In cases of sustained-virological response (SVR or cure) after an ultra-short duration (≤ 27 days) of direct-acting antiviral (DAA)-based therapy, despite HCV being detected at end of treatment (EOT), have been reported. Established HCV mathematical models that predict the treatment duration required to achieve cure do not take into account the possibility that the infectivity of virus produced during treatment might be reduced. The aim of this study was to develop a new mathematical model that considers the fundamental and critical concept that HCV RNA in serum represents both infectious virus (V i) and non-infectious virus (V ni) in ordermore » to explain the observation of cure with ultrashort DAA therapy. Established HCV models were compared to the new mathematical model to retrospectively explain cure in 2 patients who achieved cure after 24 or 27 days of paritaprevir, ombitasvir, dasabuvir, ritonavir and ribavirin or sofosbuvir plus ribavirin, respectively. Fitting established models with measured longitudinal HCV viral loads indicated that in both cases, cure would not have been expected without an additional 3–6 weeks of therapy after the actual EOT. In contrast, the new model fits the observed outcome by considering that in addition to blocking V i and V ni production (ε~0.998), these DAA + ribavirin treatments further enhanced the ratio of V ni to V i, thus increasing the log (V ni/V i) from 1 at pretreatment to 6 by EOT, which led to <1 infectious-virus particle in the extracellular body fluid (i.e., cure) prior to EOT. This new model can explain cure after short duration of DAA + ribavirin therapy by suggesting that a minimum 6-fold increase of log (V ni/V i) results from drug-induced enhancement of the V ni/V i.« less

Modeling HCV cure after an ultra-short duration of therapy with direct acting agents

DOE PAGES

Goyal, Ashish; Lurie, Yoav; Meissner, Eric G.; ...

2017-06-30

In cases of sustained-virological response (SVR or cure) after an ultra-short duration (≤ 27 days) of direct-acting antiviral (DAA)-based therapy, despite HCV being detected at end of treatment (EOT), have been reported. Established HCV mathematical models that predict the treatment duration required to achieve cure do not take into account the possibility that the infectivity of virus produced during treatment might be reduced. The aim of this study was to develop a new mathematical model that considers the fundamental and critical concept that HCV RNA in serum represents both infectious virus (V i) and non-infectious virus (V ni) in ordermore » to explain the observation of cure with ultrashort DAA therapy. Established HCV models were compared to the new mathematical model to retrospectively explain cure in 2 patients who achieved cure after 24 or 27 days of paritaprevir, ombitasvir, dasabuvir, ritonavir and ribavirin or sofosbuvir plus ribavirin, respectively. Fitting established models with measured longitudinal HCV viral loads indicated that in both cases, cure would not have been expected without an additional 3–6 weeks of therapy after the actual EOT. In contrast, the new model fits the observed outcome by considering that in addition to blocking V i and V ni production (ε~0.998), these DAA + ribavirin treatments further enhanced the ratio of V ni to V i, thus increasing the log (V ni/V i) from 1 at pretreatment to 6 by EOT, which led to <1 infectious-virus particle in the extracellular body fluid (i.e., cure) prior to EOT. This new model can explain cure after short duration of DAA + ribavirin therapy by suggesting that a minimum 6-fold increase of log (V ni/V i) results from drug-induced enhancement of the V ni/V i.« less

Effects of exercise intensity and duration on nocturnal heart rate variability and sleep quality.

PubMed

Myllymäki, Tero; Rusko, Heikki; Syväoja, Heidi; Juuti, Tanja; Kinnunen, Marja-Liisa; Kyröläinen, Heikki

2012-03-01

Acute physical exercise may affect cardiac autonomic modulation hours or even days during the recovery phase. Although sleep is an essential recovery period, the information on nocturnal autonomic modulation indicated by heart rate variability (HRV) after different exercises is mostly lacking. Therefore, this study investigated the effects of exercise intensity and duration on nocturnal HR, HRV, HR, and HRV-based relaxation, as well as on actigraphic and subjective sleep quality. Fourteen healthy male subjects (age 36 ± 4 years, maximal oxygen uptake 49 ± 4 ml/kg/min) performed five different running exercises on separate occasions starting at 6 p.m. with HR guidance at home. The effect of intensity was studied with 30 min of exercises at intensities corresponding to HR level at 45% (easy), 60% (moderate) and 75% (vigorous) of their maximal oxygen uptake. The effect of duration was studied with 30, 60, and 90 min of moderate exercises. Increased exercise intensity elevated nocturnal HR compared to control day (p < 0.001), but it did not affect nocturnal HRV. Nocturnal HR was greater after the day with 90- than 30- or 60-min exercises (p < 0.01) or control day (p < 0.001). Nocturnal HRV was lower after the 90-min exercise day compared to control day (p < 0.01). Neither exercise intensity nor duration had any impact on actigraphic or subjective sleep quality. The results suggest that increased exercise intensity and/or duration cause delayed recovery of nocturnal cardiac autonomic modulation, although long exercise duration was needed to induce changes in nocturnal HRV. Increased exercise intensity or duration does not seem to disrupt sleep quality.

Effect of low-dose, short-duration creatine supplementation on anaerobic exercise performance.

PubMed

Hoffman, Jay R; Stout, Jeffrey R; Falvo, Michael J; Kang, Jie; Ratamess, Nicholas A

2005-05-01

To examine the efficacy of a low-dose, short-duration creatine monohydrate supplement, 40 physically active men were randomly assigned to either a placebo or creatine supplementation group (6 g of creatine monohydrate per day). Testing occurred before and at the end of 6 days of supplementation. During each testing session, subjects performed three 15-second Wingate anaerobic power tests. No significant (p > 0.05) group or time differences were observed in body mass, peak power, mean power, or total work. In addition, no significant (p > 0.05) differences were observed in peak power, mean power, or total work. However, the change in the rate of fatigue of total work was significantly (p < 0.05) lower in the creatine supplementation group than in the placebo group, indicating a reduced fatigue rate in subjects supplementing with creatine compared with the placebo. Although the results of this study demonstrated reduced fatigue rates in patients during high-intensity sprint intervals, further research is necessary in examining the efficacy of low-dose, short-term creatine supplementation.

Duration of treatment for asymptomatic bacteriuria during pregnancy.

PubMed

Widmer, Mariana; Lopez, Ivana; Gülmezoglu, A Metin; Mignini, Luciano; Roganti, Ariel

2015-11-11

A previous Cochrane systematic review has shown that antibiotic drug treatment of asymptomatic bacteriuria in pregnant women substantially decreases the risk of pyelonephritis and reduces the risk of preterm delivery. However, it is not clear whether single-dose therapy is as effective as longer conventional antibiotic treatment. To assess the effects of different durations of treatment for asymptomatic bacteriuria in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2015) and reference lists of identified articles. Randomized and quasi-randomized trials comparing antimicrobial therapeutic regimens that differed in duration (particularly comparing single dose with longer duration regimens) in pregnant women diagnosed with asymptomatic bacteriuria. Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We assessed the quality of the evidence using the GRADE approach. We included 13 studies, involving 1622 women. All were comparisons of single-dose treatment with short-course (four- to seven-day) treatments. The risk of bias of trials included in this review was largely unclear, and most trials were at high risk of performance bias. The quality of the evidence was assessed using the GRADE approach. When the any antibiotic agent was used, the 'no cure' rate for asymptomatic bacteriuria in pregnant women was slightly lower for the short-course treatment over the single-dose treatment, although there was evidence of statistical heterogeneity (average risk ratio (RR) 1.28, 95% confidence interval (CI) 0.87 to 1.88; women = 1502, studies = 13; I² = 56%; very low quality evidence). Data from only good quality trials also showed better cure rates with short (four- to seven-day) regimens of the same microbial agent (average RR 1.72, 95% CI 1.27 to 2.33; women = 803, studies = two; I² = 0%; high quality evidence). There was no clear difference in the

Listening to "Frequent Flyers": What Persistently Disciplined Students Have to Say about Being Labeled as "Bad"

ERIC Educational Resources Information Center

Kennedy-Lewis, Brianna L.; Murphy, Amy S.

2016-01-01

Background: Educators' increased use of suspension and expulsion has led to some students repeatedly losing access to learning opportunities. Students excluded from school are at a higher risk of dropping out, with those who receive multiple sanctions, often called "frequent flyers" by K-12 educators, faring even worse. The loss of…

Preservation media, durations and cell concentrations of short-term storage affect key features of human adipose-derived mesenchymal stem cells for therapeutic application.

PubMed

Zhang, Fengli; Ren, Huaijuan; Shao, Xiaohu; Zhuang, Chao; Chen, Yantian; Qi, Nianmin

2017-01-01

Adipose-derived mesenchymal stem cells (ADSCs) have shown great potential in the treatment of various diseases. However, the optimum short-term storage condition of ADSCs in 2∼8 °C is rarely reported. This study aimed at optimizing a short-term storage condition to ensure the viability and function of ADSCs before transplantation. Preservation media and durations of storage were evaluated by cell viability, apoptosis, adhesion ability and colony-forming unit (CFU) capacity of ADSCs. The abilities of cell proliferation and differentiation were used to optimize cell concentrations. Optimized preservation condition was evaluated by cell surface markers, cell cycle and immunosuppressive capacity. A total of 5% human serum albumin in multiple electrolytes (ME + HSA) was the optimized medium with high cell viability, low cluster rate, good adhesion ability and high CFU capacity of ADSCs. Duration of storage should be limited to 24 h to ensure the quality of ADSCs before transplantation. A concentration of 5 × 10 6 cells/ml was the most suitable cell concentration with low late stage apoptosis, rapid proliferation and good osteogenic and adipogenic differentiation ability. This selected condition did not change surface markers, cell cycle, indoleamine 2, 3-dioxygenase 1 (IDO1) gene expression and kynurenine (Kyn) concentration significantly. In this study, ME + HSA was found to be the best medium, most likely due to the supplement of HSA which could protect cells, the physiological pH (7.4) of ME and sodium gluconate ingredient in ME which could provide energy for cells. Duration should be limited to 24 h because of reduced nutrient supply and increased waste and lactic acid accumulation during prolonged storage. To keep cell proliferation and limit lactic acid accumulation, the proper cell concentration is 5× 10 6 cells/ml. Surface markers, cell cycle and immunosuppressive capacity did not change significantly after storage using the optimized condition, which

NASA 14 Day Undersea Missions: A Short-Duration Spaceflight Analog for Immune System Dysregulation?

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Chouker, A.; Feuerecker, M.; Quiriarte, H.; Pierson, D. L.; Sams, C. F.

2011-01-01

This poster paper reviews the use of 14 day undersea missions as a possible analog for short duration spaceflight for the study of immune system dysregulation. Sixteen subjects from the the NASA Extreme Enviro nment Mission Operations (NEEMO) 12, 13 and 14 missions were studied for immune system dysregulation. The assays that are presented in this poster are the Virleukocyte subsets, the T Cell functions, and the intracellular/secreted cytokine profiles. Other assays were performed, but are not included in this presntation.

Patterning of Thick Parylene Films by Oxygen Plasma for Application as Exploding Foil Initiator Flyer Material

DTIC Science & Technology

2009-09-01

exploding foil initiator ( EFI ) type fuzes are being explored to...Acronyms Au gold Cr chromium Cu copper EFI exploding foil initiator BOE buffered oxide etch MEMS microelectromechanical systems RIE reactive ion...Patterning of Thick Parylene Films by Oxygen Plasma for Application as Exploding Foil Initiator Flyer Material by Eugene Zakar and Michael

Short sleep duration as a risk factor for hypercholesterolemia: analyses of the National Longitudinal Study of Adolescent Health.

PubMed

Gangwisch, James E; Malaspina, Dolores; Babiss, Lindsay A; Opler, Mark G; Posner, Kelly; Shen, Sa; Turner, J Blake; Zammit, Gary K; Ginsberg, Henry N

2010-07-01

To explore the relationship between sleep duration in adolescence and hypercholesterolemia in young adulthood. Experimental sleep restriction has been shown to significantly increase total cholesterol and LDL cholesterol levels in women. Short sleep duration has been found in cross sectional studies to be associated with higher total cholesterol and lower HDL cholesterol levels. Sleep deprivation could increase the risk for hypercholesterolemia by increasing appetite and dietary consumption of saturated fats, decreasing motivation to engage in regular physical activity, and increasing stress and resultant catecholamine induced lipolysis. No previous published population studies have examined the longitudinal relationship between sleep duration and high cholesterol. Multivariate longitudinal analyses stratified by sex of the ADD Health using logistic regression. United States nationally representative, school-based, probability-based sample. Adolescents (n = 14,257) in grades 7 to 12 at baseline (1994-95) and ages 18 to 26 at follow-up (2001-02). Among females, each additional hour of sleep was associated with a significantly decreased odds of being diagnosed with high cholesterol in young adulthood (OR = 0.85, 95% CI 0.75-0.96) after controlling for covariates. Additional sleep was associated with decreased, yet not statistically significant, odds ratios for hypercholesterolemia in males (OR = 0.91, 95% CI 0.79-1.05). Short sleep durations in adolescent women could be a significant risk factor for high cholesterol. Interventions that lengthen sleep could potentially serve as treatments and as primary preventative measures for hypercholesterolemia.

Changes in Sleep Duration, Timing, and Quality as Children Transition to Kindergarten

PubMed Central

Cairns, Alyssa; Harsh, John

2014-01-01

Sleep can be seen as a biologically driven behavior shaped by cultural context. A “poor fit” occurs when contextual demands for the timing and duration sleep periods are incompatible with the underlying biology. Such contextual factors are well-known for adults, yet little is known of the contextual factors that shape young children’s sleep health and to what degree such factors impact sleep duration, timing, and quality. This study attempted to identify how the transition to kindergarten was associatedwith changes in sleep timing, duration, and quality for children enrolled in preschool prior to attending kindergarten vs. those who were not. Wrist actigraphy in 38 5-yearold children was collected at three longitudinal points before and after the start of kindergarten. Our data suggested that the transition to kindergarten was associated with a reduction in weekday sleep (mostly due to lost napping) and an advance in the weekday nocturnal sleep period that was most pronounced for children not enrolled in preschool prior to kindergarten. These sleep changes paralleled objective and caregiver-reported data of increased sleep pressure that lasted well into the first month of kindergarten. PMID:24364713

Asian-White disparities in short sleep duration by industry of employment and occupation in the US: a cross-sectional study

PubMed Central

2014-01-01

Background Although short sleep is associated with an increased risk of morbidity as well as mortality and has been shown to vary by industry of employment and occupation, little is known about the relationship between work and sleep among Asian Americans. Methods Using a nationally representative sample of US adults (n = 125,610) in the National Health Interview Survey from 2004–2011, we estimated prevalence ratios for self-reported short sleep duration (<7 hours) in Asians compared to Whites by industry of employment and occupation using adjusted Poisson regression models with robust variance. Results Asians were more likely to report short sleep duration than Whites (33 vs. 28%, p < 0.001), and the Asian-White disparity was widest in finance/information and healthcare industries. Compared to Whites after adjustments, short sleep was also more prevalent among Asians employed in Public administration (PR = 1.35 [95% CI: 1.17,1.56]), Education (PR = 1.29 [95% CI: 1.08,1.53]), and Professional/Management (PR = 1.18 [95% CI: 1.03,1.36]). Short sleep, however, was lower among Asians in Accommodation/Food (PR = 0.81 [95% CI: 0.66, 0.99]) with no difference in Retail. In professional and support-service occupations, short sleep was higher among Asians, but was not different among laborers. Conclusions U.S. Asian-White disparities in short sleep varied by industries, suggesting a need to consider both race and occupational characteristics to identify high-risk individuals. PMID:24894508

Asian-White disparities in short sleep duration by industry of employment and occupation in the US: a cross-sectional study.

PubMed

Jackson, Chandra L; Kawachi, Ichiro; Redline, Susan; Juon, Hee-Soon; Hu, Frank B

2014-06-03

Although short sleep is associated with an increased risk of morbidity as well as mortality and has been shown to vary by industry of employment and occupation, little is known about the relationship between work and sleep among Asian Americans. Using a nationally representative sample of US adults (n = 125,610) in the National Health Interview Survey from 2004-2011, we estimated prevalence ratios for self-reported short sleep duration (<7 hours) in Asians compared to Whites by industry of employment and occupation using adjusted Poisson regression models with robust variance. Asians were more likely to report short sleep duration than Whites (33 vs. 28%, p < 0.001), and the Asian-White disparity was widest in finance/information and healthcare industries. Compared to Whites after adjustments, short sleep was also more prevalent among Asians employed in Public administration (PR = 1.35 [95% CI: 1.17,1.56]), Education (PR = 1.29 [95% CI: 1.08,1.53]), and Professional/Management (PR = 1.18 [95% CI: 1.03,1.36]). Short sleep, however, was lower among Asians in Accommodation/Food (PR = 0.81 [95% CI: 0.66, 0.99]) with no difference in Retail. In professional and support-service occupations, short sleep was higher among Asians, but was not different among laborers. U.S. Asian-White disparities in short sleep varied by industries, suggesting a need to consider both race and occupational characteristics to identify high-risk individuals.

OAST-Flyer is deployed by the Remote Manipulator System (RMS) as viewed from the flight deck

NASA Image and Video Library

1996-01-14

STS072-320-014 (17 Jan. 1996) --- The end effect of the Space Shuttle Endeavour's Remote Manipulator System (RMS) is about to grapple the Office of Aeronautics and Space Technology's (OAST) -- Flyer satellite. The view was recorded with a 35mm camera aimed through one of Endeavour's overheard windows on the aft flight deck.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curtis, Alexander D.; Banishev, Alexandr A.; Shaw, William L.

We investigated the launch and target impact of laser-driven Al flyer plates using photon Doppler velocimetry (PDV). We studied different flyer designs launched by laser pulses of different energies, pulse durations and beam diameters, that produced km s{sup −1} impacts with transparent target materials. Laser-launching Al flyers 25–100 μm thick cemented to glass substrates is usually thought to involve laser vaporization of a portion of the flyer, which creates many difficulties associated with loss of integrity and heating of the flyer material. However, in the system used here, the launch mechanism was surprising and unexpected: it involved optical damage atmore » the glass/cement/flyer interface, with very little laser light reaching the flyer itself. In fact the flyers launched in this manner behaved almost identically to multilayer flyers that were optically shielded from the laser pulses and insulated from heat generated by the pulses. Launching flyers with nanosecond laser pulses creates undesirable reverberating shocks in the flyer. In some cases, with 10 ns launch pulses, the thickest flyers were observed to lose integrity. But with stretched 20 ns pulses, we showed that the reverberations damped out prior to impact with targets, and that the flyers maintained their integrity during flight. Flyer impacts with salt, glass, fused silica, and acrylic polymer were studied by PDV, and the durations of fully supported shocks in those media were determined, and could be varied from 5 to 23 ns.« less

Influence of condensation on heat flux and pressure measurements in a detonation-based short-duration facility

NASA Astrophysics Data System (ADS)

Haase, S.; Olivier, H.

2017-10-01

Detonation-based short-duration facilities provide hot gas with very high stagnation pressures and temperatures. Due to the short testing time, complex and expensive cooling techniques of the facility walls are not needed. Therefore, they are attractive for economical experimental investigations of high-enthalpy flows such as the flow in a rocket engine. However, cold walls can provoke condensation of the hot combustion gas at the walls. This has already been observed in detonation tubes close behind the detonation wave, resulting in a loss of tube performance. A potential influence of condensation at the wall on the experimental results, like wall heat fluxes and static pressures, has not been considered so far. Therefore, in this study the occurrence of condensation and its influence on local heat flux and pressure measurements has been investigated in the nozzle test section of a short-duration rocket-engine simulation facility. This facility provides hot water vapor with stagnation pressures up to 150 bar and stagnation temperatures up to 3800 K. A simple method has been developed to detect liquid water at the wall without direct optical access to the flow. It is shown experimentally and theoretically that condensation has a remarkable influence on local measurement values. The experimental results indicate that for the elimination of these influences the nozzle wall has to be heated to a certain temperature level, which exclusively depends on the local static pressure.

School-Based Sleep Education Programs for Short Sleep Duration in Adolescents: A Systematic Review and Meta-Analysis.

PubMed

Chung, Ka-Fai; Chan, Man-Sum; Lam, Ying-Yin; Lai, Cindy Sin-Yee; Yeung, Wing-Fai

2017-06-01

Insufficient sleep among students is a major school health problem. School-based sleep education programs tailored to reach large number of students may be one of the solutions. A systematic review and meta-analysis was conducted to summarize the programs' effectiveness and current status. Electronic databases were searched up until May 2015. Randomized controlled trials of school-based sleep intervention among 10- to 19-year-old students with outcome on total sleep duration were included. Methodological quality of the studies was assessed using the Cochrane's risk of bias assessment. Seven studies were included, involving 1876 students receiving sleep education programs and 2483 attending classes-as-usual. Four weekly 50-minute sleep education classes were most commonly provided. Methodological quality was only moderate, with a high or an uncertain risk of bias in several domains. Compared to classes-as-usual, sleep education programs produced significantly longer weekday and weekend total sleep time and better mood among students at immediate post-treatment, but the improvements were not maintained at follow-up. Limited by the small number of studies and methodological limitations, the preliminary data showed that school-based sleep education programs produced short-term benefits. Future studies should explore integrating sleep education with delayed school start time or other more effective approaches. © 2017, American School Health Association.

Short-duration respirometry underestimates metabolic rate for discontinuous breathers.

PubMed

Winwood-Smith, Hugh S; White, Craig R

2018-06-07

Metabolic rate is commonly estimated from rates of gas exchange. An underappreciated factor that can influence estimates is patterns of pulmonary respiration. Amphibians display discontinuous respiratory patterns, often including long apnoeas, in addition to cutaneous gas exchange. The contribution of cutaneous exchange increases at low temperatures when metabolic rate is low. Due to the relatively low permeability of skin, measurements that disproportionately capture cutaneous exchange can produce underestimates of metabolic rate. The permeability of amphibian skin to CO 2 is greater than O 2 , therefore calculating the ratio of whole-animal CO 2 emission to O 2 uptake (the respiratory exchange ratio, RER) can be used to avoid underestimates of metabolic rate by ensuring that observed values of RER fall within the normal physiological range (∼0.7 to 1). Using data for cane toads Rhinella marina we show that short-duration measurements lead to underestimates of metabolic rate and overestimates of RER. At low temperatures this problem is exacerbated, requiring over 12 hours for RER to fall within the normal physiological range. Many published values of metabolic rate in animals that utilise cutaneous exchange may be underestimates. © 2018. Published by The Company of Biologists Ltd.

Distinguishing short duration noise transients in LIGO data to improve the PyCBC search for gravitational waves from high mass binary black hole mergers

NASA Astrophysics Data System (ADS)

Nitz, Alexander H.

2018-02-01

‘Blip glitches’ are a type of short duration transient noise in LIGO data. The cause for the majority of these is currently unknown. Short duration transient noise creates challenges for searches of the highest mass binary black hole systems, as standard methods of applying signal consistency, which look for consistency in the accumulated signal-to-noise of the candidate event, are unable to distinguish many blip glitches from short duration gravitational-wave signals due to similarities in their time and frequency evolution. We demonstrate a straightforward method, employed during Advanced LIGO’s second observing run, including the period of joint observation with the Virgo observatory, to separate the majority of this transient noise from potential gravitational-wave sources. This yields a  ∼20% improvement in the detection rate of high mass binary black hole mergers (> 60 Mȯ ) for the PyCBC analysis.

Shuttle payload vibroacoustic test plan evaluation. Free flyer payload applications and sortie payload parametric variations

NASA Technical Reports Server (NTRS)

Stahle, C. V.; Gongloff, H. R.

1977-01-01

A preliminary assessment of vibroacoustic test plan optimization for free flyer STS payloads is presented and the effects on alternate test plans for Spacelab sortie payloads number of missions are also examined. The component vibration failure probability and the number of components in the housekeeping subassemblies are provided. Decision models are used to evaluate the cost effectiveness of seven alternate test plans using protoflight hardware.

Healthy or Unhealthy on Sale? A cross-sectional study on the proportion of healthy and unhealthy foods promoted through flyer advertising by supermarkets in the Netherlands.

PubMed

Ravensbergen, Eva A H; Waterlander, Wilma E; Kroeze, Willemieke; Steenhuis, Ingrid H M

2015-05-06

It is generally assumed that supermarkets promote unhealthy foods more heavily than healthy foods. Promotional flyers could be an effective tool for encouraging healthier food choices; however, there is a lack of good-quality evidence on this topic. Therefore, the aim of this study was to determine the proportions of healthy and unhealthy foods on promotion in Dutch supermarket flyers. Supermarket food promotions were assessed using the weekly promotional flyers of four major Dutch supermarkets over a period of eight weeks. All promotions were evaluated for healthiness, price discount, minimum purchase amount, product category and promotion type. The level of healthiness consists of a 'healthy' group; products which have a positive effect on preventing chronic diseases and can be eaten every day. The 'unhealthy' group contain products which have adverse effects on the prevention of chronic diseases. Data were analysed using ANOVA, independent t-tests and chi-square tests. A total of 1,495 promotions were included in this study. There were more promotions in the unhealthy category; 70% of promotions were categorised as unhealthy. The price discount was greater for the healthy promotions (mean 29.5%, SD 12.1) than for the two categories of unhealthy promotions (23.7%, SD 10.8; 25.4%, SD 10.5, respectively), a tendency which was mainly due to discounts in the fruit and vegetables category. To obtain the advertised discount, a significantly higher number of products had to be purchased in the unhealthy category than in the healthier categories. Promotions in the category meat, poultry and fish category occurred frequently. Compared to traditional supermarkets, discounter supermarkets had higher percentages of unhealthy food discounts, lower discount levels and lower minimum purchase amounts. This research confirmed that unhealthy foods are more frequently advertised than healthier foods in Dutch supermarket flyers. Moreover, consumers had to buy more products to

Gastroesophageal reflux disease symptoms and dietary behaviors are significant correlates of short sleep duration in the general population: the Nagahama Study.

PubMed

Murase, Kimihiko; Tabara, Yasuharu; Takahashi, Yoshimitsu; Muro, Shigeo; Yamada, Ryo; Setoh, Kazuya; Kawaguchi, Takahisa; Kadotani, Hiroshi; Kosugi, Shinji; Sekine, Akihiro; Nakayama, Takeo; Mishima, Michiaki; Chiba, Tsutomu; Chin, Kazuo; Matsuda, Fumihiko

2014-11-01

To examine relationships among gastroesophageal reflux disease (GERD) symptoms, dietary behaviors, and sleep duration in the general population. Cross-sectional. Community-based. There were 9,643 participants selected from the general population (54 ± 13 y). None. Sleep duration, sleep habits, and unfavorable dietary behaviors of each participant were assessed with a structured questionnaire. Participants were categorized into five groups according to their sleep duration: less than 5 h, 5 to less than 6 h, 6 to less than 7 h, 7 to less than 8 h, and 8 or more h per day. GERD was evaluated using the Frequency Scale for the Symptoms of GERD (FSSG) and participants having an FSSG score of 8 or more or those under treatment of GERD were defined as having GERD. Trend analysis showed that both the FSSG score and the number of unfavorable dietary habits increased with decreasing sleep duration. Further, multiple logistic regression analysis showed that both the presence of GERD (odds ratio = 1.19, 95% confidence interval (CI) = 1.07-1.32) and the number of unfavorable dietary behaviors (odds ratio = 1.19, 95% CI = 1.13-1.26) were independent and potent factors to identify participants with short sleep duration even after controlling for other confounding factors. The current study showed that both GERD symptoms and unfavorable dietary behaviors were significant correlates of short sleep duration independently of each other in a large sample from the general population.

Acceleration from short-duration blast

NASA Astrophysics Data System (ADS)

Ritzel, D. V.; Van Albert, S.; Sajja, V.; Long, J.

2018-01-01

The blast-induced motion of spheres has been studied experimentally where the shock wave is rapidly decaying during the period that quasi-steady acceleration would be developed in the case of a step-function shock wave as considered in most shock-tube studies. The motion of sphere models ranging from 39 to 251 mm in diameter and having a range of densities was assessed using the "free-flight" method in a simulator specially designed to replicate the decaying shock wave profile of spherical blast including negative phase and positive entropy gradient. A standardized blast-wave simulation of 125 kPa and 6-ms positive-phase duration was applied for all experiments. In all cases, there are three phases to the motion: a relatively low "kickoff" velocity from the shock diffraction, acceleration or deceleration during the positive duration, then deceleration through the negative phase and subsequent quiescent air. The unexpected deceleration of larger spheres after their kickoff velocity during the decaying yet high-speed flow of the blast wave seems associated with the persistence of a ring vortex on the downstream side of the sphere. The flow is entirely unsteady with initial forces dominated by the shock diffraction; therefore, the early motion of spheres under such conditions is not governed by quasi-steady drag as in classical aerodynamics. The work will help establish scaling rules for model studies of blast-induced motion relevant to improvised explosive devices, and preliminary results are shown for motion imparted to a human skull surrogate.

Differences in short and long sleep durations between blacks and whites attributed to emotional distress: analysis of the National Health Interview Survey in the United States.

PubMed

Seixas, Azizi A; Auguste, Emmanuella; Butler, Mark; James, Caryl; Newsome, Valerie; Auguste, Evan; da Silva Fonseca, Vilma Aparecida; Schneeberger, Andres; Zizi, Ferdinand; Jean-Louis, Girardin

2017-02-01

The current study examined the role of emotional distress in explaining racial/ethnic differences in unhealthy sleep duration. Data from the 2004-2013 National Health Interview Survey were analyzed using SPSS 20. Data were collected through personal household interviews in the United States. Of the total 261,686 participants (age≥18 years), 17.0% were black, 83.0% were white, and the mean age was 48 years (SE=0.04). To ascertain total sleep duration, participants were asked, "How many hours of sleep do you get on average in a 24-hour period?" Sleep duration was coded as short sleep (<7hours), average sleep (7-8hours), or long sleep (>8hours). Emotional distress-feeling sad, nervous, restless, hopeless, worthless, and burdened over a 30-day period-was measured using Kessler-6, a 6-item screening scale. Of the participants reporting significant emotional distress (4.0% black, 3.5% white), χ 2 analyses revealed that a higher percentage of blacks, compared with whites, reported unhealthy sleep durations. Relative to Whites, Blacks had increased prevalence of short sleep (prevalence ratio=1.32, P<.001) or long sleep (odds ratio =1.189, P<.001). The interaction between race/ethnicity and emotional distress was significantly associated with short (prevalence ratio=0.99, P<.001) and long sleep (odds ratio=0.98, P<.001) durations. Individuals of the black race/ethnicity or those reporting greater levels of emotional distress are more likely to report short or long sleep duration. Emotional distress might partially explain racial/ethnic differences in unhealthy sleep duration between blacks and whites. Copyright © 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Short-Term Health-Related Quality of Life of Critically Ill Children Following Daily Sedation Interruption.

PubMed

Vet, Nienke J; de Wildt, Saskia N; Verlaat, Carin W M; Mooij, Miriam G; Tibboel, Dick; de Hoog, Matthijs; Buysse, Corinne M P

2016-11-01

Our earlier pediatric daily sedation interruption trial showed that daily sedation interruption in addition to protocolized sedation in critically ill children does not reduce duration of mechanical ventilation, length of stay, or amounts of sedative drugs administered when compared with protocolized sedation only, but undersedation was more frequent in the daily sedation interruption + protocolized sedation group. We now report the preplanned analysis comparing short-term health-related quality of life and posttraumatic stress symptoms between the two groups. Preplanned prospective part of a randomized controlled trial. Two tertiary medical-surgical PICUs in the Netherlands. Critically ill children requiring mechanical ventilation. None. Eight weeks after a child's discharge from the PICU, health-related quality of life was assessed with the validated Child Health Questionnaire and, only for children above 4 years old, posttraumatic stress was assessed with the Dutch Children's Responses to Trauma Inventory. Additionally, health-related quality of life of all study patients was compared with Dutch normative data. Of the 113 patients from two participating centers in the original study, 96 patients were eligible for follow-up and 64 patients were included (response rate, 67%). No difference was found with respect to health-related quality of life between the two study groups. None of the eight children more than 4 years old showed posttraumatic stress symptoms. Daily sedation interruption in addition to protocolized sedation for critically ill children did not seem to have an effect on short-term health-related quality of life. Also in view of the earlier found absence of effect on clinical outcome, we cannot recommend the use of daily sedation interruption + protocolized sedation.

Short-duration hypothermia after ischemic stroke prevents delayed intracranial pressure rise.

PubMed

Murtha, L A; McLeod, D D; McCann, S K; Pepperall, D; Chung, S; Levi, C R; Calford, M B; Spratt, N J

2014-07-01

Intracranial pressure elevation, peaking three to seven post-stroke is well recognized following large strokes. Data following small-moderate stroke are limited. Therapeutic hypothermia improves outcome after cardiac arrest, is strongly neuroprotective in experimental stroke, and is under clinical trial in stroke. Hypothermia lowers elevated intracranial pressure; however, rebound intracranial pressure elevation and neurological deterioration may occur during rewarming. (1) Intracranial pressure increases 24 h after moderate and small strokes. (2) Short-duration hypothermia-rewarming, instituted before intracranial pressure elevation, prevents this 24 h intracranial pressure elevation. Long-Evans rats with two hour middle cerebral artery occlusion or outbred Wistar rats with three hour middle cerebral artery occlusion had intracranial pressure measured at baseline and 24 h. Wistars were randomized to 2·5 h hypothermia (32·5°C) or normothermia, commencing 1 h after stroke. In Long-Evans rats (n = 5), intracranial pressure increased from 10·9 ± 4·6 mmHg at baseline to 32·4 ± 11·4 mmHg at 24 h, infarct volume was 84·3 ± 15·9 mm(3) . In normothermic Wistars (n = 10), intracranial pressure increased from 6·7 ± 2·3 mmHg to 31·6 ± 9·3 mmHg, infarct volume was 31·3 ± 18·4 mm(3) . In hypothermia-treated Wistars (n = 10), 24 h intracranial pressure did not increase (7·0 ± 2·8 mmHg, P < 0·001 vs. normothermia), and infarct volume was smaller (15·4 ± 11·8 mm(3) , P < 0·05). We saw major intracranial pressure elevation 24 h after stroke in two rat strains, even after small strokes. Short-duration hypothermia prevented the intracranial pressure rise, an effect sustained for at least 18 h after rewarming. The findings have potentially important implications for design of future clinical trials. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke

A Multi-Step Pathway Connecting Short Sleep Duration to Daytime Somnolence, Reduced Attention, and Poor Academic Performance: An Exploratory Cross-Sectional Study in Teenagers

PubMed Central

Perez-Lloret, Santiago; Videla, Alejandro J.; Richaudeau, Alba; Vigo, Daniel; Rossi, Malco; Cardinali, Daniel P.; Perez-Chada, Daniel

2013-01-01

Background: A multi-step causality pathway connecting short sleep duration to daytime somnolence and sleepiness leading to reduced attention and poor academic performance as the final result can be envisaged. However this hypothesis has never been explored. Objective: To explore consecutive correlations between sleep duration, daytime somnolence, attention levels, and academic performance in a sample of school-aged teenagers. Methods: We carried out a survey assessing sleep duration and daytime somnolence using the Pediatric Daytime Sleepiness Scale (PDSS). Sleep duration variables included week-days' total sleep time, usual bedtimes, and absolute weekdayto-weekend sleep time difference. Attention was assessed by d2 test and by the coding subtest from the WISC-IV scale. Academic performance was obtained from literature and math grades. Structural equation modeling was used to assess the independent relationships between these variables, while controlling for confounding effects of other variables, in one single model. Standardized regression weights (SWR) for relationships between these variables are reported. Results: Study sample included 1,194 teenagers (mean age: 15 years; range: 13-17 y). Sleep duration was inversely associated with daytime somnolence (SWR = -0.36, p < 0.01) while sleepiness was negatively associated with attention (SWR = -0.13, p < 0.01). Attention scores correlated positively with academic results (SWR = 0.18, p < 0.01). Daytime somnolence correlated negatively with academic achievements (SWR = -0.16, p < 0.01). The model offered an acceptable fit according to usual measures (RMSEA = 0.0548, CFI = 0.874, NFI = 0.838). A Sobel test confirmed that short sleep duration influenced attention through daytime somnolence (p < 0.02), which in turn influenced academic achievements through reduced attention (p < 0.002). Conclusions: Poor academic achievements correlated with reduced attention, which in turn was related to daytime somnolence. Somnolence

Neurophysiological study on the effect of various short durations of deep breathing: A randomized controlled trial.

PubMed

Cheng, Kok Suen; Han, Ray P S; Lee, Poh Foong

2018-02-01

The study aims to study the effects of short duration deep breathing on the EEG power with topography based on parallel group randomized controlled trial design which was lacking in prior reports. 50 participants were split into 4 groups: control (CONT), deep breathing (DB) for 5 (DB5), 7 (DB7), and 9 (DB9) minutes. EEG recordings were obtained during baseline, deep breathing session, after deep breathing, and a follow-up session after 7 days of consecutive practice. Frontal theta power of DB5 and DB9 was significantly larger than that of CONT after the deep breathing session (p = 0.027 and p = 0.006, respectively) and the profound finding showed that the theta topography obtained a central-focused distribution for DB7 and DB9. The result obtained was consistent with previous literature, albeit for certain deep breathing durations only, indicating a possible linkage between the deep breathing duration and the neurophysiology of the brain. Copyright © 2017 Elsevier B.V. All rights reserved.

Short Duration Combined Mild Hypothermia Improves Resuscitation Outcomes in a Porcine Model of Prolonged Cardiac Arrest

PubMed Central

Yu, Tao; Yang, Zhengfei; Li, Heng; Ding, Youde; Huang, Zitong

2015-01-01

Objective. In this study, our aim was to investigate the effects of combined hypothermia with short duration maintenance on the resuscitation outcomes in a porcine model of ventricular fibrillation (VF). Methods. Fourteen porcine models were electrically induced with VF and untreated for 11 mins. All animals were successfully resuscitated manually and then randomized into two groups: combined mild hypothermia (CH group) and normothermia group (NT group). A combined hypothermia of ice cold saline infusion and surface cooling was implemented in the animals of the CH group and maintained for 4 hours. The survival outcomes and neurological function were evaluated every 24 hours until a maximum of 96 hours. Neuron apoptosis in hippocampus was analyzed. Results. There were no significant differences in baseline physiologies and primary resuscitation outcomes between both groups. Obvious improvements of cardiac output were observed in the CH group at 120, 180, and 240 mins following resuscitation. The animals demonstrated better survival at 96 hours in the CH group when compared to the NT group. In comparison with the NT group, favorable neurological functions were observed in the CH group. Conclusion. Short duration combined cooling initiated after resuscitation improves survival and neurological outcomes in a porcine model of prolonged VF. PMID:26558261

Volatile organic compounds in runners near a roadway: increased blood levels after short-duration exercise.

PubMed

Blair, C; Walls, J; Davies, N W; Jacobson, G A

2010-08-01

To determine if non-elite athletes undertaking short duration running exercise adjacent to a busy roadway experience increased blood levels of common pollutant volatile organic compounds (benzene, toluene, ethylbenzene and xylene (BTEX)). The study was observational in design. Participants (nine males/one female non-elite athletes) ran for 20 min, near a busy roadway along a 100 m defined course at their own pace. Blood levels of BTEX were determined both pre- and post-exercise by SPME-GC-MS. Environmental BTEX levels were determined by passive adsorption samplers. Subjects completed a mean (range) distance of 4.4 (3.4 to 5.2) km over 20 min (4.5 (3.8 to 5.9) min/km pace), with a mean (SD) exercise intensity of 93 (2.3)% HR(max), and mean (SD) ventilation significantly elevated compared with resting levels (86.2 (2.3) vs 8.7 (0.9) l/min; p<0.001). The mean (SD) environmental levels (time weighted average) were determined as 53.1 (4.2), 428 (83), and 80.0 (3.7) microg/m(3) for toluene, ethylbenzene and xylenes, respectively, while benzene was below the detectable limit due to the short exposure period. Significant increases in blood BTEX levels were observed in runners between pre- and postexercise for toluene (mean increase of 1.4 ng/ml; p=0.002), ethylbenzene (0.7 ng/ml; p=0.0003), m/p-xylene (2.0 ng/ml; p=0.004) and o-xylene (1.1 ng/ml; p=0.002), but no change was observed for benzene. Blood BTEX levels are increased during high-intensity exercise such as running undertaken in areas with BTEX pollution, even with a short duration of exercise. This may have health implications for runners who regularly exercise near roadways.

The influence of PTSD, sleep fears, and neighborhood stress on insomnia and short sleep duration in urban, young adult, African Americans.

PubMed

Hall Brown, Tyish; Mellman, Thomas A

2014-01-01

African Americans residing in stressful urban environments have high rates of insomnia and short sleep duration, both of which are associated with adverse health outcomes. However, limited data exist that explore factors influencing inadequate sleep in this high-risk population. This study sought to evaluate the contributions of demographics, trauma, posttraumatic stress disorder (PTSD) symptoms, sleep fears, and neighborhood stress to both insomnia and short sleep in urban African American young adults. Data were analyzed from self-report measures completed by 378 participants 18-35 years of age. PTSD symptom severity and sleep fears were independently associated with insomnia severity, and sleep fears was associated with sleep duration. Results have implications for preventative health intervention strategies for urban African American young adults.

Properties of a Small-scale Short-duration Solar Eruption with a Driven Shock

NASA Astrophysics Data System (ADS)

Ying, Beili; Feng, Li; Lu, Lei; Zhang, Jie; Magdalenic, Jasmina; Su, Yingna; Su, Yang; Gan, Weiqun

2018-03-01

Large-scale solar eruptions have been extensively explored over many years. However, the properties of small-scale events with associated shocks have rarely been investigated. We present analyses of a small-scale, short-duration event originating from a small region. The impulsive phase of the M1.9-class flare lasted only four minutes. The kinematic evolution of the CME hot channel reveals some exceptional characteristics, including a very short duration of the main acceleration phase (<2 minutes), a rather high maximal acceleration rate (∼50 km s‑2), and peak velocity (∼1800 km s‑1). The fast and impulsive kinematics subsequently results in a piston-driven shock related to a metric type II radio burst with a high starting frequency of ∼320 MHz of the fundamental band. The type II source is formed at a low height of below 1.1 R ⊙ less than ∼2 minutes after the onset of the main acceleration phase. Through the band-split of the type II burst, the shock compression ratio decreases from 2.2 to 1.3, and the magnetic field strength of the shock upstream region decreases from 13 to 0.5 Gauss at heights of 1.1–2.3 R ⊙. We find that the CME (∼4 × 1030 erg) and flare (∼1.6 × 1030 erg) consume similar amounts of magnetic energy. The same conclusion for large-scale eruptions implies that small- and large-scale events possibly share a similar relationship between CMEs and flares. The kinematic particularities of this event are possibly related to the small footpoint-separation distance of the associated magnetic flux rope, as predicted by the Erupting Flux Rope model.

Impact of transportation duration on stress responses in day-old chicks from young and old breeders.

PubMed

Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Buyse, Johan; Tuyttens, Frank Andre Maurice

2017-06-01

The aim of this study was to assess the interaction effect of transportation duration and parental age on physiological stress responses and quality in day-old chicks. After hatch, 3240 chicks from either 29-week old (young) or 60-week old (old) broiler breeders were transported for 1.5h (short) or 11h (long). Thereafter, 228 chicks were assessed for quality and blood plasma was assayed for corticosterone (CORT), lactate, glucose, and thiobarbituric acid-reactive substances (TBARS, increased concentrations can indicate oxidative stress). No interaction effects of parental age and transportation duration were found (all P>0.10). Chicks from young breeders showed higher CORT levels (P=0.007) and were of higher quality (Tona method, P<0.001) than those from old breeders. After long transportation, chicks showed increased CORT (P<0.001) and lower TBARS levels (P<0.001) compared to after short transportation. No evidence was provided that long transportation differently affected the quality or stress responses of chicks from breeder flocks of two ages. Copyright © 2017. Published by Elsevier Ltd.

A multi-step pathway connecting short sleep duration to daytime somnolence, reduced attention, and poor academic performance: an exploratory cross-sectional study in teenagers.

PubMed

Perez-Lloret, Santiago; Videla, Alejandro J; Richaudeau, Alba; Vigo, Daniel; Rossi, Malco; Cardinali, Daniel P; Perez-Chada, Daniel

2013-05-15

A multi-step causality pathway connecting short sleep duration to daytime somnolence and sleepiness leading to reduced attention and poor academic performance as the final result can be envisaged. However this hypothesis has never been explored. To explore consecutive correlations between sleep duration, daytime somnolence, attention levels, and academic performance in a sample of school-aged teenagers. We carried out a survey assessing sleep duration and daytime somnolence using the Pediatric Daytime Sleepiness Scale (PDSS). Sleep duration variables included week-days' total sleep time, usual bedtimes, and absolute weekday to-weekend sleep time difference. Attention was assessed by d2 test and by the coding subtest from the WISC-IV scale. Academic performance was obtained from literature and math grades. Structural equation modeling was used to assess the independent relationships between these variables, while controlling for confounding effects of other variables, in one single model. Standardized regression weights (SWR) for relationships between these variables are reported. Study sample included 1,194 teenagers (mean age: 15 years; range: 13-17 y). Sleep duration was inversely associated with daytime somnolence (SWR = -0.36, p < 0.01) while sleepiness was negatively associated with attention (SWR = -0.13, p < 0.01). Attention scores correlated positively with academic results (SWR = 0.18, p < 0.01). Daytime somnolence correlated negatively with academic achievements (SWR = -0.16, p < 0.01). The model offered an acceptable fit according to usual measures (RMSEA = 0.0548, CFI = 0.874, NFI = 0.838). A Sobel test confirmed that short sleep duration influenced attention through daytime somnolence (p < 0.02), which in turn influenced academic achievements through reduced attention (p < 0.002). Poor academic achievements correlated with reduced attention, which in turn was related to daytime somnolence. Somnolence correlated with short sleep duration.

The index gage method to develop a flow duration curve from short-term streamflow records

NASA Astrophysics Data System (ADS)

Zhang, Zhenxing

2017-10-01

The flow duration curve (FDC) is one of the most commonly used graphical tools in hydrology and provides a comprehensive graphical view of streamflow variability at a particular site. For a gaged site, an FDC can be easily estimated with frequency analysis. When no streamflow records are available, regional FDCs are used to synthesize FDCs. However, studies on how to develop FDCs for sites with short-term records have been very limited. Deriving representative FDC when there are short-term hydrologic records is important. For instance, 43% of the 394 streamflow gages in Illinois have records of 20 years or fewer, and these short-term gages are often distributed in headwaters and contain valuable hydrologic information. In this study, the index gage method is proposed to develop FDCs using short-term hydrologic records via an information transfer technique from a nearby hydrologically similar index gage. There are three steps: (1) select an index gage; (2) determine changes of FDC; and (3) develop representative FDCs. The approach is tested using records from 92 U.S. Geological Survey streamflow gages in Illinois. A jackknife experiment is conducted to assess the performance. Bootstrap resampling is used to simulate various periods of records, i.e., 1, 2, 5, 10, 15, and 20 years of records. The results demonstrated that the index gage method is capable of developing a representative FDC using short-term records. Generally, the approach performance is improved when more hydrologic records are available, but the improvement appears to level off when the short-term gage has 10 years or more records.

High beam quality and high energy short-pulse laser with MOPA

NASA Astrophysics Data System (ADS)

Jin, Quanwei; Pang, Yu; Jiang, JianFeng; Tan, Liang; Cui, Lingling; Wei, Bin; Sun, Yinhong; Tang, Chun

2018-03-01

A high energy, high beam quality short-pulse diode-pumped Nd:YAG master oscillator power-amplifier (MOPA) laser with two amplifier stages is demonstrated. The two-rod birefringence compensation was used as beam quality controlling methods, which presents a short-pulse energy of 40 mJ with a beam quality value of M2 = 1.2 at a repetition rate of 400Hz. The MOPA system delivers a short-pulse energy of 712.5 mJ with a pulse width of 12.4 ns.The method of spherical aberration compensation is improved the beam quality, a M2 factor of 2.3 and an optical-to-optical efficiency of 27.7% is obtained at the maximum laser out power.The laser obtained 1.4J out energy with polarization integration.

The hazards of bad sleep-Sleep duration and quality as predictors of adolescent alcohol and cannabis use.

PubMed

Mike, Thomas B; Shaw, Daniel S; Forbes, Erika E; Sitnick, Stephanie L; Hasler, Brant P

2016-11-01

Although an association between adolescent sleep and substance use is supported by the literature, few studies have characterized the longitudinal relationship between early adolescent sleep and subsequent substance use. The current study examined the prospective association between the duration and quality of sleep at age 11 and alcohol and cannabis use throughout adolescence. The present study, drawn from a cohort of 310 boys taking part in a longitudinal study in Western Pennsylvania, includes 186 boys whose mothers completed the Child Sleep Questionnaire; sleep duration and quality at age 11 were calculated based on these reports. At ages 20 and 22, participants were interviewed regarding lifetime alcohol and cannabis use. Cox proportional hazard analysis was used to determine the association between sleep and substance use. After accounting for race, socioeconomic status, neighborhood danger, active distraction, internalizing problems, and externalizing problems, both the duration and quality of sleep at age 11 were associated with multiple earlier substance use outcomes. Specifically, less sleep was associated with earlier use, intoxication, and repeated use of both alcohol and cannabis. Lower sleep quality was associated with earlier alcohol use, intoxication, and repeated use. Additionally, lower sleep quality was associated with earlier cannabis intoxication and repeated use, but not first use. Both sleep duration and sleep quality in early adolescence may have implications for the development of alcohol and cannabis use throughout adolescence. Further studies to understand the mechanisms linking sleep and substance use are warranted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effect of freezing method and frozen storage duration on instrumental quality of lamb throughout display.

PubMed

Muela, E; Sañudo, C; Campo, M M; Medel, I; Beltrán, J A

2010-04-01

This study evaluated the effect of freezing method (FM) (air blast freezer, freezing tunnel, or nitrogen chamber) and frozen storage duration (FSD) (1, 3, or 6 months) on the instrumental measurements of quality of thawed lamb, aged for a total of 72 h, throughout a 10-d display period, compared to the quality of fresh meat. pH, colour, lipid oxidation, thawing, and cooking losses in Longissimus thoracis and lumborum muscle, were determined following standard methods. FM affected yellowness, FSD redness and thawing losses, and both affected oxidation (increased as freezing rate decreased and/or as storage duration increased). When compared with fresh meat, the main differences appeared on oxidation (where a significant interaction between treatment (3FM x 3FSD + fresh meat) with display duration was detected), and on total losses (thaw + cook losses). Oxidation was lower in fresh meat, but values were not significantly different from those stored frozen for 1 month. Fresh meat had smaller total losses than did thawed meat, but losses were not significantly different from meat frozen in the freezing tunnel and stored frozen for 1 month. Display duration had a greater effect on instrumental quality parameters than did FM or FSD. pH, b*, and oxidation increased, and L* and a* decreased with an increase in the number of days on display. In conclusion, neither freezing method nor frozen storage up to 6 months influenced extensively the properties of lamb when instrumental measurements of quality were measured in meat that had been displayed for 1d after thawing. The small deterioration shown in this study should not give consumers concerns about frozen meat. 2009 Elsevier Ltd. All rights reserved.

Inverse U-shaped Association between Sleep Duration and Semen Quality: Longitudinal Observational Study (MARHCS) in Chongqing, China

PubMed Central

Chen, Qing; Yang, Huan; Zhou, Niya; Sun, Lei; Bao, Huaqiong; Tan, Lu; Chen, Hongqiang; Ling, Xi; Zhang, Guowei; Huang, Linping; Li, Lianbing; Ma, Mingfu; Yang, Hao; Wang, Xiaogang; Zou, Peng; Peng, Kaige; Liu, Taixiu; Cui, Zhihong; Ao, Lin; Roenneberg, Till; Zhou, Ziyuan; Cao, Jia

2016-01-01

Study Objectives: To investigate the association between sleep duration and semen parameters as well as reproductive hormone levels. Methods: We designed a cohort of male college students in Chongqing, China. A total of 796 subjects were recruited in 2013 and 656 (82.4%) were followed up in 2014. Each time, semen and peripheral blood samples were collected for semen quality and reproductive hormone measurement. Sleep duration was estimated by revised Munich Chronotype Questionnaire. In 2014, sleep quality was also measured by Pittsburgh Sleep Quality Index (PSQI). Results: There was a substantial inverse U-shaped association between sleep duration and two semen parameters (semen volume and total sperm number), with 7.0–7.5 h/day of sleep showing highest parameters. Either longer or shorter sleep was associated with decreased semen parameters in a dose-response manner (P = 0.002 and 0.001, respectively). Sleeping > 9.0 h was associated with a 21.5% (95% confidence interval 9.2, 32.2) reduction in semen volume and 39.4% (23.3, 52.1) reduction in total sperm number; sleeping ≤ 6.5 h was associated with 4.6% (−10.5, 22.3) and 25.7% (−1.2, 60.1) reduction. Increase of the two parameters was found in those who changed sleep duration toward 7.0–7.5 h/day from 2013 to 2014. The U-shaped association was independent from PSQI and was replicated in another dataset of 1,346 males. No association found between sleep duration and reproductive hormone. Conclusions: Either restricted or excessive sleep may impair semen quality. Further research is needed to validate this finding. Citation: Chen Q, Yang H, Zhou N, Sun L, Bao H, Tan L, Chen H, Ling X, Zhang G, Huang L, Li L, Ma M, Yang H, Wang X, Zou P, Peng K, Liu T, Cui Z, Ao L, Roenneberg T, Zhou Z, Cao J. Inverse u-shaped association between sleep duration and semen quality: longitudinal observational study (MARHCS) in Chongqing, China. SLEEP 2016;39(1):79–86. PMID:26350472

Short-duration exercise and confinement alters bone mineral content and shape in weanling horses.

PubMed

Hiney, K M; Nielsen, B D; Rosenstein, D

2004-08-01

The hypothesis that short-duration exercise may ameliorate the decrease in bone mass observed with confinement was investigated with 18 quarter horses (nine colts and nine fillies) weaned at 4 mo of age and placed into box stalls. After a 5-wk adjustment period, individuals were grouped by age and weight, and then divided randomly into three treatment groups: 1) group housed; 2) confined with no exercise; and 3) confined with exercise. The confined and exercised groups were housed in 3.7 m x 3.7 m box stalls for the 56-d duration of the trial. The exercised group was sprinted 82 m/d, 5 d/wk, in a fenced grass alleyway. The weanlings were led down an alleyway, turned loose in a small pen, and then released and allowed to run back down the alley. The group horses were housed together in a 992-m2 drylot with free access to exercise. On d 0, 28, and 56, dorsopalmar and lateromedial radiographs of the left third metacarpal bone were taken to estimate changes in bone mineral content and cortical widths. Mean values of medial, lateral, and total radiographic bone aluminum equivalence increased over time (P < 0.05), whereas dorsal and palmar radiographic bone aluminum equivalence did not change significantly. Dorsal, medial, and total radiographic bone aluminum equivalence tended (P = 0.09) to differ by a treatment x day interaction, with values increasing over time only in the exercised group. Normalized medial and total radiographic bone aluminum equivalence tended (P < 0.1) to differ (P < 0.01) with treatment, with exercised horses having greater bone aluminum equivalence than confined horses. Dorsopalmar cortical width in exercised horses was greater than on d 56 (treatment x day; P = 0.07). The dorsopalmar medullary cavity decreased in exercised vs. group-housed horses (P = 0.027), whereas dorsal and medial cortical width tended to increase only in the exercised horses (treatment x day; P < 0.01). This study indicated that a short-duration exercise protocol might be

Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity

PubMed Central

Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Lambrecht, Evelien; Gellynck, Xavier; Tuyttens, Frank A. M.

2016-01-01

Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion (FC) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post

Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity.

PubMed

Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Lambrecht, Evelien; Gellynck, Xavier; Tuyttens, Frank A M

2016-09-01

Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion ( FC: ) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post

Effect of freezing method and frozen storage duration on lamb sensory quality.

PubMed

Muela, E; Sañudo, C; Campo, M M; Medel, I; Beltrán, J A

2012-01-01

This study assessed the effect of three freezing methods with three frozen storage durations (1, 3, and 6 months) on the sensory quality of lamb. Methods were: air blast freezer, freezing tunnel+air blast freezer, and nitrogen chamber+air blast freezer. Meat was frozen after 48 h of ageing (0-4°C). Fresh meat (72 h ageing at 2-4°C) was used as control. Sensory analyses (trained panel and consumer tests) were performed on loin chops (Longissimus lumborum) after 24 h of thawing. Results from the trained panel test showed that freezing (method and/or storage duration) had no significant effect. Consumers found that freezing affected sensory quality. Cluster analysis for overall acceptability divided the population into four classes with different preference patterns, and none of them showed a significant preference for fresh meat. The small differences between fresh and thawed meat shown in this study should not give consumers concerns about buying frozen meat or consuming thawed meat. Copyright © 2011. Published by Elsevier Ltd.

Time-to-isolation guided titration of freeze duration in 3rd generation short-tip cryoballoon pulmonary vein isolation - Comparable clinical outcome and shorter procedure duration.

PubMed

Pott, Alexander; Kraft, Christoph; Stephan, Tilman; Petscher, Kerstin; Rottbauer, Wolfgang; Dahme, Tillman

2018-03-15

The optimal freeze duration in cryoballoon pulmonary vein isolation (PVI) is unknown. The 3rd generation cryoballoon facilitates observation of the time-to-isolation (TTI) and thereby enables individualized cryoenergy titration. To evaluate the efficacy of an individualized freeze duration we compared the clinical outcome of patients treated with a TTI-guided ablation protocol to the outcome of patients treated with a fixed ablation protocol. We compared 100 patients treated with the 3rd generation cryoballoon applying a TTI-based protocol (TTI group) to 100 patients treated by a fixed freeze protocol (fixed group). In the fixed group a 240s freeze cycle was followed by a 240s bonus freeze after acute PV isolation. In the TTI group freeze duration was 180s if TTI was ≥30s and reduced to only 120s, if TTI was <30s. In case of a TTI >60s a 180s bonus freeze was applied. Freedom from atrial arrhythmia recurrence off class I/III antiarrhythmic drugs after one year was not different between the TTI group (73.6%) and the fixed group (75.7%; p=0.75). Mean procedure duration was 85.8±27.3min in the TTI group compared to 115.7±27.1min in the fixed group (p<0.001). Mean fluoroscopy time was 17.5±6.6min in the TTI group and 22.5±9.8min in the fixed group (p<0.001). TTI-guided cryoenergy titration leads to reduced procedure duration and fluoroscopy time and appears to be as effective as a fixed ablation strategy. A single 2-minute freeze seems to be sufficient in case of short TTI. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Local short-duration precipitation extremes in Sweden: observations, forecasts and projections

NASA Astrophysics Data System (ADS)

Olsson, Jonas; Berg, Peter; Simonsson, Lennart

2015-04-01

Local short-duration precipitation extremes (LSPEs) are a key driver of hydrological hazards, notably in steep catchments with thin soils and in urban environments. The triggered floodings, landslides, etc., have large consequences for society in terms of both economy and health. Accurate estimations of LSPEs on both climatological time-scales (past, present, future) and in real-time is thus of great importance for improved hydrological predictions as well as design of constructions and infrastructure affected by hydrological fluxes. Analysis of LSPEs is, however, associated with various limitations and uncertainties. These are to a large degree associated with the small-scale nature of the meteorological processes behind LSPEs and the associated requirements on observation sensors as well as model descriptions. Some examples of causes for the limitations involved are given in the following. - Observations: High-resolution data sets available for LSPE analyses are often limited to either relatively long series from one or a few stations or relatively short series from larger station networks. Radar data have excellent resolutions in both time and space but the estimated local precipitation intensity is still highly uncertain. New and promising techniques (e.g. microwave links) are still in their infancy. - Weather forecasts (short-range): Although forecasts with the required spatial resolution for potential generation of LSPEs (around 2-4 km) are becoming operationally available, the actual forecast precision of LSPEs is largely unknown. Forecasted LSPEs may be displaced in time or, more critically, in space which strongly affects the possibility to assess hydrological risk. - Climate projections: The spatial resolution of the current RCM generation (around 25 km) is not sufficient for proper description of LSPEs. Statistical post-processing (i.e. downscaling) is required which adds substantial uncertainty to the final result. Ensemble generation of sufficiently

A dual-armed free flyer

NASA Technical Reports Server (NTRS)

Beck, D.; Das, B.; Dickson, C.; Douglas, B.; Long, L.; Middour, K.; Reid, S.; Uber, J.; Walsh, G.; Wang, L.

1989-01-01

This summary presents the main conclusions and results of the design studies conducted by a group of 13 students at the University of Maryland. The students, all participants in the spring 1989 course ENEE418 in the Electrical Engineering Department, met weekly in a two-hour class to discuss and evaluate design alternatives. The main problem considered was the design and control of a planar testbed simulating a free-flying space robot for applications in satellite servicing. This project grew out of the 1988 class where a dual-armed free flyer (DAFF) was designed and partially built. This year, a group of six students continued the development of the DAFF, achieving computer-controlled motion of the DAFF's arms. All fabrication and testing of the DAFF is being conducted in the Intelligent Servosystems Laboratory at the University of Maryland. While the work related to the design and development of the DAFF is the main subject of the report, it should be noted that other students in the ENEE418 class have investigated additional issues related to manipulation in space. For example, one group studied a new parallel linkage based manipulator for fine motion applications such as in assembly operations in space. They investigated the mechanism's kinematics, its reachable workspace, and precision of applying forces and torques. In yet another project, a student set out to measure and map the friction characteristics of the actuators used in the Modular Dextrous Hand, which has been recently developed in the Intelligent Servosystems Laboratory. The results are expected to help compensate for this friction, which is a highly nonlinear disturbance and presents significant problems in high-precision, low-speed operations. This summary continues with the discussion of the results obtained by the group of students who have been working on developing the DAFF testbed.

Short-Duration Gamma-Ray Burst in the Multi-Messenger Era

NASA Astrophysics Data System (ADS)

Lazzati, Davide

2016-12-01

The detection of gravitational waves (GW) from binary black hole mergers has been an historical, transformative event in physics and astronomy, heralded by most as the beginning of multi-messenger astronomy. With the increase of sensitivity over the next few years, LIGO and Virgo are predicted to detect mergers from neutron-star (NS) binaries. These are expected to be the first true multi-messenger sources, being the progenitors of short-duration gamma-ray burst (SGRB). The simultaneous detection of a gravitational, electromagnetic, and possibly neutrino signals from the same source would dramatically enhance the scientific output of each individual detection. Important details of the connection between SGRBs and NS binary mergers are however poorly known. These include the nature of the merging compact objects, their equation of state, the physics of SGRB jets - such as their Lorentz factors and opening angles, and the possibility of small temporal delays among the GW, n! eutrino, and gamma-ray signals. In view of the expected increased sensitivity of LIGO during the upcoming observing period and beyond, there is urgent need of improving our understanding of the physics of SGRBs to support the detection of GWs (and possibly neutrinos) and to develop a context in which the expected multi-messenger signal can be properly interpreted and its potential fully exploited. To achieve such goals, we propose to carry out a comprehensive study of relativistic jets from compact binary mergers, exploiting the most recent advances in numerical techniques developed within this research group. The ansatz of this study will be that within a short time after a compact merger a relativistic jet is created. Subsequently, the jet interacts with the merger environment, imprinting a signature that can be detected in the temporal and spectral properties of the prompt radiation, both in its electromagnetic and neutrino components. Analogous dynamical effects have been observed and studied

Defining the possibilities: is short duration treatment of chronic hepatitis C genotype 1 with sofosbuvir-containing regimens likely to be as effective as current regimens?

PubMed

Nafisi, Shirin; Roy, Sabyasachi; Gish, Robert; Manch, Richard; Kohli, Anita

2016-01-01

This review summarizes published data on sofosbuvir-based regimens for patients infected with HCV GT1 with a focus on evaluating the optimal and possible durations of treatment. PubMed and conference abstract books published between 2011-2015 were searched. HCV treatment has decreased from 24 week regimens to studies done as short as 4 weeks. History of prior treatment or cirrhosis have consistently shown lower SVR12 rates with shorter duration therapies. Low cure rates have been seen in patients within 4 week trials, however, select patients with low fibrosis scores, low HCV VL and HCV GT-1b have moderate cure rates. Most patients will require 12-24 weeks of therapy. Further studies are needed to elucidate the predictors of treatment response to short duration therapies and optimal combination of DAAs.

Muscle Adaptations Following Short-Duration Bed Rest with Integrated Resistance, Interval, and Aerobic Exercise

NASA Technical Reports Server (NTRS)

Hackney, Kyle J.; Scott, Jessica M.; Buxton, Roxanne; Redd-Goetchius, Elizabeth; Crowell, J. Brent; Everett, Meghan E.; Wickwire, Jason; Ryder, Jeffrey W.; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

2011-01-01

Unloading of the musculoskeletal system during space flight results in deconditioning that may impair mission-related task performance in astronauts. Exercise countermeasures have been frequently tested during bed rest (BR) and limb suspension; however, high-intensity, short-duration exercise prescriptions have not been fully explored. PURPOSE: To determine if a high intensity resistance, interval, and aerobic exercise program could protect against muscle atrophy and dysfunction when performed during short duration BR. METHODS: Nine subjects (1 female, 8 male) performed a combination of supine exercises during 2 weeks of horizontal BR. Resistance exercise (3 d / wk) consisted of squat, leg press, hamstring curl, and heel raise exercises (3 sets, 12 repetitions). Aerobic (6 d / wk) sessions alternated continuous (75% VO2 peak) and interval exercise (30 s, 2 min, and 4 min) and were completed on a supine cycle ergometer and vertical treadmill, respectively. Muscle volumes of the upper leg were calculated pre, mid, and post-BR using magnetic resonance imaging. Maximal isometric force (MIF), rate of force development (RFD), and peak power of the lower body extensors were measured twice before BR (averaged to represent pre) and once post BR. ANOVA with repeated measures and a priori planned contrasts were used to test for differences. RESULTS: There were no changes to quadriceps, hamstring, and adductor muscle volumes at mid and post BR time points compared to pre BR (Table 1). Peak power increased significantly from 1614 +/- 372 W to 1739 +/- 359 W post BR (+7.7%, p = 0.035). Neither MIF (pre: 1676 +/- 320 N vs. post: 1711 +/- 250 N, +2.1%, p = 0.333) nor RFD (pre: 7534 +/- 1265 N/ms vs. post: 6951 +/- 1241 N/ms, -7.7%, p = 0.136) were significantly impaired post BR.

Plasma processes in water under effect of short duration pulse discharges

NASA Astrophysics Data System (ADS)

Gurbanov, Elchin

2013-09-01

It is very important to get a clear water without any impurities and bacteria by methods, that don't change the physical and chemical indicators of water now. In this article the plasma processes during the water treatment by strong electric fields and short duration pulse discharges are considered. The crown discharge around an electrode with a small radius of curvature consists of plasma leader channels with a high conductivity, where the thermo ionization processes and UV-radiation are taken place. Simultaneously the partial discharges around potential electrode lead to formation of atomic oxygen and ozone. The spark discharge arises, when plasma leader channels cross the all interelectrode gap, where the temperature and pressure are strongly grown. As a result the shock waves and dispersing liquid streams in all discharge gap are formed. The plasma channels extend, pressure inside it becomes less than hydrostatic one and the collapse and UV-radiation processes are started. The considered physical processes can be successfully used as a basis for development of pilot-industrial installations for conditioning of drinking water and to disinfecting of sewage.

Relationship between Mobile Phone Addiction and the Incidence of Poor and Short Sleep among Korean Adolescents: a Longitudinal Study of the Korean Children & Youth Panel Survey.

PubMed

Lee, Joo Eun; Jang, Sung In; Ju, Yeong Jun; Kim, Woorim; Lee, Hyo Jung; Park, Eun Cheol

2017-07-01

Three of ten teenagers in Korea are addicted to mobile phones. The aim of this study was to examine the relationship between mobile phone addiction and the incidence of poor sleep quality and short sleep duration in adolescents. We used longitudinal data from the Korean Children & Youth Panel Survey conducted by the National Youth Policy Institute in Korea (2011-2013). A total of 1,125 students at baseline were included in this study after excluding those who already had poor sleep quality or short sleep duration in the previous year. A generalized estimating equation was used to analyze the data. High mobile phone addiction (mobile phone addiction score > 20) increased the risk of poor sleep quality but not short sleep duration. We suggest that consistent monitoring and effective intervention programs are required to prevent mobile phone addiction and improve adolescents' sleep quality. © 2017 The Korean Academy of Medical Sciences.

Relationship between Mobile Phone Addiction and the Incidence of Poor and Short Sleep among Korean Adolescents: a Longitudinal Study of the Korean Children & Youth Panel Survey

PubMed Central

2017-01-01

Three of ten teenagers in Korea are addicted to mobile phones. The aim of this study was to examine the relationship between mobile phone addiction and the incidence of poor sleep quality and short sleep duration in adolescents. We used longitudinal data from the Korean Children & Youth Panel Survey conducted by the National Youth Policy Institute in Korea (2011–2013). A total of 1,125 students at baseline were included in this study after excluding those who already had poor sleep quality or short sleep duration in the previous year. A generalized estimating equation was used to analyze the data. High mobile phone addiction (mobile phone addiction score > 20) increased the risk of poor sleep quality but not short sleep duration. We suggest that consistent monitoring and effective intervention programs are required to prevent mobile phone addiction and improve adolescents' sleep quality. PMID:28581275

Detecting long-duration cloud contamination in hyper-temporal NDVI imagery

NASA Astrophysics Data System (ADS)

Ali, Amjad; de Bie, C. A. J. M.; Skidmore, A. K.

2013-10-01

Cloud contamination impacts on the quality of hyper-temporal NDVI imagery and its subsequent interpretation. Short-duration cloud impacts are easily removed by using quality flags and an upper envelope filter, but long-duration cloud contamination of NDVI imagery remains. In this paper, an approach that goes beyond the use of quality flags and upper envelope filtering is tested to detect when and where long-duration clouds are responsible for unreliable NDVI readings, so that a user can flag those data as missing. The study is based on MODIS Terra and the combined Terra-Aqua 16-day NDVI product for the south of Ghana, where persistent cloud cover occurs throughout the year. The combined product could be assumed to have less cloud contamination, since it is based on two images per day. Short-duration cloud effects were removed from the two products through using the adaptive Savitzky-Golay filter. Then for each 'cleaned' product an unsupervised classified map was prepared using the ISODATA algorithm, and, by class, plots were prepared to depict changes over time of the means and the standard deviations in NDVI values. By comparing plots of similar classes, long-duration cloud contamination appeared to display a decline in mean NDVI below the lower limit 95% confidence interval with a coinciding increase in standard deviation above the upper limit 95% confidence interval. Regression analysis was carried out per NDVI class in two randomly selected groups in order to statistically test standard deviation values related to long-duration cloud contamination. A decline in seasonal NDVI values (growing season) were below the lower limit of 95% confidence interval as well as a concurrent increase in standard deviation values above the upper limit of the 95% confidence interval were noted in 34 NDVI classes. The regression analysis results showed that differences in NDVI class values between the Terra and the Terra-Aqua imagery were significantly correlated (p < 0.05) with

Development of a short duration backlit pinhole for radiography on the National Ignition Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huntington, C. M.; Krauland, C. M.; Kuranz, C. C.

2010-10-15

Experiments on the National Ignition Facility (NIF) will require bright, short duration, near-monochromatic x-ray backlighters for radiographic diagnosis of many high-energy density systems. This paper details a vanadium pinhole backlighter producing (1.8{+-}0.5)x10{sup 15} x-ray photons into 4{pi} sr near the vanadium He-like characteristic x-ray energy of 5.18 keV. The x-ray yield was quantified from a set of Ross filters imaged to a calibrated image plate, with the Dante diagnostic used to confirm the quasimonochromatic nature of the spectrum produced. Additionally, an x-ray film image shows a source-limited image resolution of 26 {mu}m from a 20 {mu}m diameter pinhole.

The effect of short duration transportation on serum cortisol response in alpacas (Llama pacos).

PubMed

Anderson, D E; Grubb, T; Silveira, F

1999-03-01

This research project evaluated the changes in serum cortisol in six male and six female alpacas in response to transportation of short duration. All alpacas were subjected to trailer transportation for 30 min. Serum samples were obtained prior to transportation, immediately after transportation, and after a 4-h recovery period. Heart rate was recorded at each time interval and observations of individual behavioural characteristics were recorded. Data were analysed using analysis of variance. Heart rate was not significantly changed by transportation stress. Serum cortisol concentration was significantly higher after transportation, but head returned to baseline concentration after the 4-h recovery period. Behavioural characteristics were not associated with changes in serum cortisol concentration.

Sleep Duration, Schedule and Quality among Urban Chinese Children and Adolescents: Associations with Routine After-School Activities

PubMed Central

Jiang, Xiaoxiao; Hardy, Louise L.; Baur, Louise A.; Ding, Ding; Wang, Ling; Shi, Huijing

2015-01-01

Background With rapid urbanization accompanied by lifestyle changes, children and adolescents living in metropolitan areas are faced with many time use choices that compete with sleep. This study reports on the sleep hygiene of urban Chinese school students, and investigates the relationship between habitual after-school activities and sleep duration, schedule and quality on a regular school day. Methods Cross-sectional, school-based survey of school children (Grades 4–8) living in Shanghai, China, conducted in 2011. Self-reported data were collected on students’ sleep duration and timing, sleep quality, habitual after-school activities (i.e. homework, leisure-time physical activity, recreational screen time and school commuting time), and potential correlates. Results Mean sleep duration of this sample (mean age: 11.5-years; 48.6% girls) was 9 hours. Nearly 30% of students reported daytime tiredness. On school nights, girls slept less (p<0.001) and went to bed later (p<0.001), a sex difference that was more pronounced in older students. Age by sex interactions were observed for both sleep duration (p=0.005) and bedtime (p=0.002). Prolonged time spent on homework and mobile phone playing was related to shorter sleep duration and later bedtime. Adjusting for all other factors, with each additional hour of mobile phone playing, the odds of daytime tiredness and having difficulty maintaining sleep increased by 30% and 27% among secondary students, respectively. Conclusion There are sex differences in sleep duration, schedule and quality. Habitual activities had small but significant associations with sleep hygiene outcomes especially among secondary school students. Intervention strategies such as limiting children’s use of electronic screen devices after school are implicated. PMID:25611973

Association between Screen Viewing Duration and Sleep Duration, Sleep Quality, and Excessive Daytime Sleepiness among Adolescents in Hong Kong

PubMed Central

Mak, Yim Wah; Wu, Cynthia Sau Ting; Hui, Donna Wing Shun; Lam, Siu Ping; Tse, Hei Yin; Yu, Wing Yan; Wong, Ho Ting

2014-01-01

Screen viewing is considered to have adverse impacts on the sleep of adolescents. Although there has been a considerable amount of research on the association between screen viewing and sleep, most studies have focused on specific types of screen viewing devices such as televisions and computers. The present study investigated the duration with which currently prevalent screen viewing devices (including televisions, personal computers, mobile phones, and portable video devices) are viewed in relation to sleep duration, sleep quality, and daytime sleepiness among Hong Kong adolescents (N = 762). Television and computer viewing remain prevalent, but were not correlated with sleep variables. Mobile phone viewing was correlated with all sleep variables, while portable video device viewing was shown to be correlated only with daytime sleepiness. The results demonstrated a trend of increase in the prevalence and types of screen viewing and their effects on the sleep patterns of adolescents. PMID:25353062

Association between screen viewing duration and sleep duration, sleep quality, and excessive daytime sleepiness among adolescents in Hong Kong.

PubMed

Mak, Yim Wah; Wu, Cynthia Sau Ting; Hui, Donna Wing Shun; Lam, Siu Ping; Tse, Hei Yin; Yu, Wing Yan; Wong, Ho Ting

2014-10-28

Screen viewing is considered to have adverse impacts on the sleep of adolescents. Although there has been a considerable amount of research on the association between screen viewing and sleep, most studies have focused on specific types of screen viewing devices such as televisions and computers. The present study investigated the duration with which currently prevalent screen viewing devices (including televisions, personal computers, mobile phones, and portable video devices) are viewed in relation to sleep duration, sleep quality, and daytime sleepiness among Hong Kong adolescents (N = 762). Television and computer viewing remain prevalent, but were not correlated with sleep variables. Mobile phone viewing was correlated with all sleep variables, while portable video device viewing was shown to be correlated only with daytime sleepiness. The results demonstrated a trend of increase in the prevalence and types of screen viewing and their effects on the sleep patterns of adolescents.

Relationship between sleep duration and self-reported health-related quality of life among US adults with or without major chronic diseases, 2014.

PubMed

Liu, Yong; Wheaton, Anne G; Croft, Janet B; Xu, Fang; Cunningham, Timothy J; Greenlund, Kurt J

2018-06-01

To assess the association between sleep duration and health-related quality of life (HRQOL) among adults with or without chronic conditions. Using the 2014 Behavioral Risk Factor Surveillance System, we analyzed self-reported data from adult respondents aged ≥18 years with (n=277,757, unhealthy group) and without (n=172,052. healthy group) reported history of any of nine chronic conditions (coronary heart disease, stroke, cancer, chronic obstructive pulmonary disease, diabetes, asthma, arthritis, depression, chronic kidney disease). Multivariable logistic regressions were separately constructed to assess the associations between sleep duration and four self-reported HRQOL measures after adjustment for sociodemographics, leisure-time physical activity, body mass index, and smoking status among unhealthy and healthy adults. The prevalence of poor/fair health, frequent physical distress, frequent mental distress, frequent activity limitation, and short sleep duration was 27.9%, 19.3%, 17.0%, 13.6%, and 38.3% in the unhealthy group and 6.9%, 4.0%, 5.3%, 2.1%, and 31.0% in the healthy group, respectively. U-shaped relationships of sleep duration to all four HRQOL indicators were observed among the unhealthy group and to poor/fair health, frequent mental distress, and frequent activity limitation among the healthy group. The relationships further varied by sex, age, race/ethnicity, and BMI category among the healthy group. Relationships between extreme sleep duration and HRQOLs were observed among both healthy and unhealthy groups. These results can help inform public awareness campaigns and physician-counseling regarding the importance of sleep for mental health and well-being. Copyright © 2018. Published by Elsevier Inc.

Sleep quality and duration in relation to memory in the elderly: Initial results from the Hellenic Longitudinal Investigation of Aging and Diet.

PubMed

Tsapanou, A; Gu, Y; O'Shea, D M; Yannakoulia, M; Kosmidis, M; Dardiotis, E; Hadjigeorgiou, G; Sakka, P; Stern, Y; Scarmeas, N

2017-05-01

Sleep is crucial for cognition, particularly for memory, given its complex association with neurodegenerative processes. The aim of the present study was to examine the association between sleep quality as well as sleep duration and memory performance in a Greek elderly population. Cross-sectional design in the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD), a population representative study of Greek elderly (65years or older). Data from 1589 participants free of sleep medication were included. Sleep quality was estimated by using the Sleep Scale from the Medical Outcomes Study. An extensive neuropsychological assessment examining memory was administered to each participant. Linear regression analyses were used to examine whether sleep quality (higher score, poor quality) and/or sleep duration were associated with memory expressed in the form of a z-score. Age, sex, education, and body mass index were included as covariates. The main analyses were conducted first on the total sample, then with the exclusion of demented participants, and finally with the exclusion of both demented and participants with Mild Cognitive Impairment (MCI). We then conducted further analyses on the non-demented, non-MCI group, initially stratified by Apolipoprotein E-ε4 gene. We further examined the role of co-morbidities, as well as the association between sleep duration groups and memory. We also explored any interaction effect between sex and sleep quality/duration on memory. We then examined the associations between components of sleep measures and memory scores. Lastly, we examined the associations between sleep quality/duration and verbal/non-verbal memory separately. In the total sample, we noted significant associations between sleep duration and memory (B=-0.001, p≤0.0001), but not for sleep quality and memory (B=-0.038, p=0.121). After excluding the demented participants, the associations were significant for: sleep quality and memory (B=-0.054, p=0.023), and

Short Duration Reduced Gravity Drop Tower Design and Development

NASA Astrophysics Data System (ADS)

Osborne, B.; Welch, C.

The industrial and commercial development of space-related activities is intimately linked to the ability to conduct reduced gravity research. Reduced gravity experimentation is important to many diverse fields of research in the understanding of fundamental and applied aspects of physical phenomena. Both terrestrial and extra-terrestrial experimental facilities are currently available to allow researchers access to reduced gravity environments. This paper discusses two drop tower designs, a 2.0 second facility built in Australia and a proposed 2.2 second facility in the United Kingdom. Both drop towers utilise a drag shield for isolating the falling experiment from the drag forces of the air during the test. The design and development of The University of Queensland's (Australia) 2.0 second drop tower, including its specifications and operational procedures is discussed first. Sensitive aspects of the design process are examined. Future plans are then presented for a new short duration (2.2 sec) ground-based reduced gravity drop tower. The new drop tower has been designed for Kingston University (United Kingdom) to support teaching and research in the field of reduced gravity physics. The design has been informed by the previous UQ drop tower design process and utilises a catapult mechanism to increase test time and also incorporates features to allow participants for a variety of backgrounds (from high school students through to university researchers) to learn and experiment in reduced gravity. Operational performance expectations for this new facility are also discussed.

Enhanced conflict monitoring via a short-duration, video-assisted deep breathing in healthy young adults: an event-related potential approach through the Go/NoGo paradigm.

PubMed

Cheng, Kok Suen; Chang, Yun Fah; Han, Ray P S; Lee, Poh Foong

2017-01-01

Practitioners of mindfulness are reported to have greater cognitive control especially in conflict monitoring, response inhibition and sustained attention. However, due to the various existing methods in each mindfulness practices and also, the high commitment factor, a barrier still exists for an individual to pick up the practices. Therefore, the effect of short duration deep breathing on the cognitive control is investigated here. Short duration guided deep breathing videos consisting of 5, 7 and 9 min respectively were created and used on subjects training. The effect on cognitive control was assessed using a Go/NoGo task along with event-related potential (ERP) measurements at Fz, Cz, and Pz. From the study, the significant outcome showed at the follow-up session in which participants engaged for 5 min deep breathing group showed a profound NoGo N2 amplitude increment as compared to the control group, indicating an enhanced conflict monitoring ability. An inverse relationship between the NoGo N2 amplitude and the breathing duration is observed as well at the follow-up session. These results indicated the possibility of performing short duration deep breathing guided by a video to achieve an enhanced conflict monitoring as an alternative to other mindfulness practices and 5 min is found to be the optimum practice duration. This study is the first to establish a relationship between deep breathing and conflict monitoring through ERP. The study population of young adults taken from the same environment reduces the variance in ERP results due to age and environment. A larger sample size would provide a greater statistical power. A longer duration of deep breathing should be investigated to further clarify the relationship between the practice duration and the NoGo N2 amplitude. The result can be split by gender and analyzed separately due to the different brain structure of males and females.

Short-duration therapeutic massage reduces postural upper trapezius muscle activity.

PubMed

Domingo, Antoinette R; Diek, Melissa; Goble, Kathleen M; Maluf, Katrina S; Goble, Daniel J; Baweja, Harsimran S

2017-01-18

Massage therapy has historically been used as a therapeutic treatment to help reduce pain and promote relaxation. The aim of this study was to investigate the effect of therapeutic massage on the upper trapezius muscles, which are commonly associated with increased muscle tension. This was a randomized crossover study. Seventeen healthy individuals (nine women; 24.5±4.0 years) participated in the study. All individuals participated in two sessions that were held 24 h apart. In one of the sessions, the participants received a moderate pressure massage applied to the shoulders and neck. In the other session, participants sat quietly. The order of the sessions was counterbalanced across participants. Muscle activity, as measured by surface electromyography, of the upper trapezius muscles was recorded. The amount of muscle activity change following massage was compared with the change in muscle activity following quiet sitting. Muscle activity of the upper trapezius reduced significantly (19.3%; P=0.004) following massage compared with muscle activity following quiet sitting (1.0%). Our findings suggest that short-duration moderate pressure massage leads to a reduction in upper trapezius muscle activity. This result has potential implications for clinical populations such as those with chronic neck pain.

Prevalence of Obesity, No Leisure-Time Physical Activity, and Short Sleep Duration Among Occupational Groups in 29 States.

PubMed

Birdsey, Jan; Sussell, Aaron L

2017-12-01

The aim of this study was to examine prevalence of obesity (body mass index of 30 or higher), no leisure-time physical activity in the past 30 days (no LTPA), and short sleep duration (averaging less than 7 hours of sleep per 24-hour period) among 22 occupational groups. We analyzed 2013 and 2014 Behavioral Risk Factor Surveillance System (BRFSS) data from 29 states, controlling for sex, age, race/ethnicity, and education. By occupation, prevalence ranged from 16.1% to 35.8% for obesity, 11.3% to 28.7% for no LTPA, and 31.4% to 42.9% for short sleep. Only Transportation & Material Moving ranked among the top five occupations for all three risk factors. Obesity and no LTPA varied significantly by sex for several occupations. Prevalence of obesity, no LTPA, and short sleep varied by occupation and affected more than one in five U.S. workers.

A flyer-impact technique for measuring viscosity of metal under shock compression

NASA Astrophysics Data System (ADS)

Li, Yilei; Liu, Fusheng; Ma, Xiaojuan; Li, Yinglei; Yu, Ming; Zhang, Jichun; Jing, Fuqian

2009-01-01

A flyer-impact technique, different from the explosive method of [Sakharov et al., Sov. Phys. Dokl. 9, 1091 (1965)], is developed to investigate the viscosity of shocked metals. The shock wave with a front of sinusoidal perturbation is induced by the sinusoidal profile of the impact surface of the sample by use of two-stage light-gas gun. The oscillatory damping process of the perturbation amplitude is monitored by electric pins. Two damping curves (perturbation amplitude relative to its initial value versus propagated distance relative to the wavelength of sinusoidal perturbation) of aluminum are determined at 78 and 101 GPa. The effective shear viscosity coefficients are deduced to be about 1300 and 800 Pa s based on the Miller and Ahrens analytic solution for viscous fluid.

A tool to estimate the Fermi Large Area Telescope background for short-duration observations

DOE PAGES

Vasileiou, Vlasios

2013-07-25

Here, the proper estimation of the background is a crucial component of data analyses in astrophysics, such as source detection, temporal studies, spectroscopy, and localization. For the case of the Large Area Telescope (LAT) on board the Fermi spacecraft, approaches to estimate the background for short (≲1000 s duration) observations fail if they ignore the strong dependence of the LAT background on the continuously changing observational conditions. We present a (to be) publicly available background-estimation tool created and used by the LAT Collaboration in several analyses of Gamma Ray Bursts. This tool can accurately estimate the expected LAT background formore » any observational conditions, including, for example, observations with rapid variations of the Fermi spacecraft’s orientation occurring during automatic repointings.« less

Vestibular vertigo is associated with abnormal sleep duration.

PubMed

Albathi, Monirah; Agrawal, Yuri

2017-01-01

Several small studies in animals and humans have suggested a relationship between vestibular function and sleep. In this study, we evaluate the association between vestibular vertigo and sleep duration in a large, representative sample of US adults. We used data from the National Health Interview Survey, which administered a Balance Supplement in 2008 in a sample of 20,950 adult respondents. We evaluated the cross-sectional association between vestibular vertigo (based on a well-validated definition) and sleep duration (defined as short <6 hours, normal 6-8 hours, and long >8 hours). We performed multiple and multinomial logistic regression analyses to estimate the odds ratio and relative risk ratio (RRR) of impaired sleep duration compared to normal sleep duration associated with vestibular vertigo. Analyses were adjusted for demographic, lifestyle and health behavior characteristics as well as relevant comorbid conditions. Thirty percent of individuals with vestibular vertigo reported abnormal sleep duration (15.5% short duration and 14.8% long duration). In adjusted analyses, individuals with vestibular vertigo had a 1.75 (95% CI 1.45-2.11) RRR of having short sleep duration compared to individuals without vestibular vertigo, and a 1.55 (95% CI 1.26-1.91) RRR of having long sleep duration compared to individuals without vestibular vertigo. This study presents epidemiologic evidence to support the association between vestibular function and sleep duration. Individuals with vestibular vertigo had a higher RRR for abnormally short or long sleep duration. Further work is needed to evaluate the causal direction(s) of this association.

Q-switched all-fiber laser with short pulse duration based on tungsten diselenide

NASA Astrophysics Data System (ADS)

Li, Wenyi; OuYang, Yuyi; Ma, Guoli; Liu, Mengli; Liu, Wenjun

2018-05-01

Fiber lasers are widely used in industrial processing, sensing, medical and communications applications due to their simple structure, good stability and low cost. With the rapid development of fiber lasers and the sustained improvement of industrial laser quality requirements, researchers in ultrafast optics focus on how to get laser pulses with high output power and narrow pulse duration. Q-switched technology is one of the most effective techniques to generate ultrashort pulses. In this paper, a tungsten diselenide saturable absorber with 16.82% modulation depth is prepared by chemical vapor deposition. Experimental results show that when the pump power changes from 115.7 mW to 630 mW, the all-fiber laser can achieve a stable Q-switched pulse output. The repetition rate of the output pulse varies from 80.32 kHz to 204.2 kHz, the pulse duration is 581 ns, the maximum output power is 17.1 mW and the maximum pulse energy is 83.7 nJ. Results in this paper show that tungsten diselenide can be applied to ultrafast optics, which is a kind of saturable absorption material with excellent properties.

Short duration microgravity experiments in physical and life sciences during parabolic flights: the first 30 ESA campaigns.

PubMed

Pletser, Vladimir

2004-11-01

Aircraft parabolic flights provide repetitively up to 20 s of reduced gravity during ballistic flight manoeuvres. Parabolic flights are used to conduct short microgravity investigations in Physical and Life Sciences, to test instrumentation and to train astronauts before a space flight. The European Space Agency (ESA) has organized since 1984 thirty parabolic flight campaigns for microgravity research experiments utilizing six different airplanes. More than 360 experiments were successfully conducted during more than 2800 parabolas, representing a cumulated weightlessness time of 15 h 30 m. This paper presents the short duration microgravity research programme of ESA. The experiments conducted during these campaigns are summarized, and the different airplanes used by ESA are shortly presented. The technical capabilities of the Airbus A300 'Zero-G' are addressed. Some Physical Science, Technology and Life Science experiments performed during the last ESA campaigns with the Airbus A300 are presented to show the interest of this unique microgravity research tool to complement, support and prepare orbital microgravity investigations. c2004 Elsevier Ltd. All rights reserved.

Application of the World Health Organization Quality of Life Instrument, Short Form (WHOQOL-BREF) to patients with cataract.

PubMed

Gholami, Ali; Araghi, Mahmood Tavakoli; Shamsabadi, Fatemeh; Bayat, Mahdiye; Dabirkhani, Fatemeh; Moradpour, Farhad; Mansori, Kamyar; Moradi, Yousef; Rajabi, Abdolhalim

2016-01-01

Cataract is a prevalent disease in the elderly, and negatively influences patients' quality of life. This study was conducted to study the application of the World Health Organization Quality of Life Instrument, Short Form (WHOQOL-BREF) to patients with cataract. In this cross-sectional study, 300 patients with cataract were studied in Neyshabur, Iran from July to October 2014. The Iranian version of the WHOQOL-BREF questionnaire was used to measure their quality of life. Cronbach's alpha coefficient, Pearson's correlation coefficient, the paired t-test, the independent t-test, and a linear regression model were used to analyze the data in SPSS version 16.0 (SPSS Inc., Chicago, IL, USA). The mean age of the participants was 68.11±11.98 years, and most were female (53%). The overall observed Cronbach's alpha coefficient for the WHOQOL-BREF was 0.889, ranging from 0.714 to 0.810 in its four domains. The total mean score of the respondents on the WHOQOL-BREF was 13.19. The highest and lowest mean scores were observed in the social relationship domain (14.11) and the physical health domain (12.29), respectively. A backward multiple linear regression model found that duration of disease and marital status were associated with total WHOQOL scores, while age, duration of disease, marital status, and income level were associated with domains one through four, respectively (p<0.05). The reliability analysis conducted in this study indicated that the WHOQOL-BREF scale exhibited an acceptable degree of internal consistency in the measurement of the quality of life of patients with cataract. It was also found that the patients with cataract who were surveyed reported a relatively moderate quality of life.

Risk factors, health risks, and risk management for aircraft personnel and frequent flyers.

PubMed

Kim, Jeoum Nam; Lee, Byung Mu

2007-01-01

Health risks associated with long periods of time in flight are of concern to astronauts, crew members, and passengers. Many epidemiological studies showed that occupational and frequent flyers may be susceptible to ocular, cardiovascular, neurological, pulmonary, gastrointestinal, sensory, immunological, physiological, and even developmental disorders. In addition, the incidences of cancer and food poisoning are expected to be higher in such individuals. This article reviews health risks and risk factors associated with air travel, and discusses risk management strategies. To reduce adverse health risks, risk factors such as radiation, infection, stress, temperature, pressure, and circadian rhythm need to be avoided or reduced to levels that are as low as technologically achievable to protect flight personnel and passengers.

Solitary phalanx plasmacytoma relapse with disseminated extramedullary plasmacytomas and myeloma after short duration of remission.

PubMed

Celik, I; Baltali, E; Barişta, I; Tekuzman, G; Kansu, E; Atahan, L; Güngen, Y; Firat, D

1996-01-01

Solitary bone plasmacytomas account for 5-7% of multiple myeloma cases and are assumed to have a fairly good prognosis, with a long duration of relapse-free survival after primary local treatment. Isolated phalanx plasmacytoma is a very rare entity, because involvement of extremities is seen in less than 1% of all solitary bone plasmacytomas, where they are usually localized centripedally, often in the axial skeleton. A 68 year old patient with a lytic lesion involving 5th phalanx was diagnosed as having a biopsy-proven solitary plasmacytoma, with a negative work-up for coexisting plasma cell dyscrasia. Three and a half months after completion of radiotherapy of the involved phalanx, the patient was readmitted with hypercalcemia, renal insufficiency and subsequently diagnosed as having atypical plasma cell infiltration of marrow, and plasmacytomas involving the right vocal cord and the premaxillary region, as well as pathological ulna fracture. Plasmacytoma of the phalanx, with extreme short duration of remission and an aggressive type of clinical relapse, is in sharp contrast with the natural stable course of a solitary plasmacytoma where the use of systemic treatment is subject to intense debate.

Decreased frequency and duration of tooth brushing is a risk factor for endothelial dysfunction.

PubMed

Matsui, Shogo; Kajikawa, Masato; Maruhashi, Tatsuya; Iwamoto, Yumiko; Iwamoto, Akimichi; Oda, Nozomu; Kishimoto, Shinji; Hidaka, Takayuki; Kihara, Yasuki; Chayama, Kazuaki; Goto, Chikara; Aibara, Yoshiki; Nakashima, Ayumu; Noma, Kensuke; Taguchi, Akira; Higashi, Yukihito

2017-08-15

Periodontal disease is associated with endothelial dysfunction, leading to cardiovascular disease. The effect of detailed tooth brushing behavior, not only frequency but also duration of tooth brushing, on endothelial function is unclear. The purpose of this study was to evaluate the relationships of detailed methods of tooth brushing with vascular function. We evaluated flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation, and frequency and duration of tooth brushing in 896 subjects. We divided the subjects into three groups according to the frequency and duration of tooth brushing: low frequency and short duration group (short duration group (short duration group (≥twice/day and ≥2min/procedure). FMD in the low frequency and short duration group was significantly lower than FMD in the low frequency or short duration group and FMD in the non-low frequency and non-short duration group [3.1 (2.7)% vs. 4.2 (3.1)% and 4.7 (3.1)%, P=0.001 and <0.001, respectively]. Nitroglycerine-induced vasodilation was similar in the three groups. Using the non-low frequency and non-short duration group as the reference, the low frequency and short duration of tooth brushing group was significantly associated with an increased odds ratio of a low FMD tertile after adjustment for conventional risk factors (OR: 2.25, 95% CI: 1.39-3.59; P<0.001). These findings suggest that low frequency and short duration of tooth brushing are associated with endothelial dysfunction. URL for clinical trial: http://UMIN; registration number for clinical trial: UMIN000003409. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Duration of treatment for asymptomatic bacteriuria during pregnancy.

PubMed

Villar, J; Lydon-Rochelle, M T; Gülmezoglu, A M; Roganti, A

2000-01-01

A Cochrane systematic review has shown that drug treatment of asymptomatic bacteriuria in pregnant women substantially decreases the risk of pyelonephritis and reduces the risk of preterm delivery. However, it is not clear whether single dose therapy is as effective as longer conventional antibiotic treatment. The objective of this review was to assess the effects of different durations of treatment for asymptomatic bacteriuria in pregnancy. We searched the Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and the reference lists of articles. Randomised and quasi-randomised trials comparing antimicrobial therapeutic regimens that differed in duration (particularly comparing single dose with longer duration regimens) in pregnant women diagnosed with asymptomatic bacteriuria. Trial quality was assessed and data were extracted independently by the reviewers. Eight studies involving over 400 women were included. All were comparisons of single dose treatment with four to seven day treatments. The trials were generally of poor quality. No difference in 'no-cure' rate was detected between single dose and short course (4-7 day) treatment for asymptomatic bacteriuria in pregnant women (relative risk 1.13, 95% confidence interval 0.82 to 1.54) as well as in the recurrent asymptomtic bacteriuria (relative risk 1.08, 95% confidence interval 0.70 to 1.66). However these results showed significant heterogeneity. No differences were detected for preterm births and pyelonephritis although sample size of trials was small. Longer duration treatment was associated with an increase in reports of adverse effects (relative risk 0.53, 95% confidence interval 0.31 to 0.91). There is not enough evidence to evaluate whether single dose or longer duration doses are more effective in treating asymptomatic bacteriuria in pregnant women. Because single dose has lower cost and increases compliance, this comparison should be explored in a properly

Short video interventions to reduce mental health stigma: a multi-centre randomised controlled trial in nursing high schools.

PubMed

Winkler, Petr; Janoušková, Miroslava; Kožený, Jiří; Pasz, Jiří; Mladá, Karolína; Weissová, Aneta; Tušková, Eva; Evans-Lacko, Sara

2017-12-01

We aimed to assess whether short video interventions could reduce stigma among nursing students. A multi-centre, randomised controlled trial was conducted. Participating schools were randomly selected and randomly assigned to receive: (1) an informational leaflet, (2) a short video intervention or (3) a seminar involving direct contact with a service user. The Community Attitudes towards Mental Illness (CAMI) and Reported and Intended Behaviour Scale (RIBS) were selected as primary outcome measures. SPANOVA models were built and Cohen's d calculated to assess the overall effects in each of the trial arms. Compared to the baseline, effect sizes immediately after the intervention were small in the flyer arm (CAMI: d = 0.25; RIBS: d = 0.07), medium in the seminar arm (CAMI: d = 0.61; RIBS: d = 0.58), and medium in the video arm (CAMI: d = 0.49 RIBS: d = 0.26; n = 237). Effect sizes at the follow-up were vanishing in the flyer arm (CAMI: d = 0.05; RIBS: d = 0.04), medium in the seminar arm (CAMI: d = 0.43; RIBS: d = 0.26; n = 254), and small in the video arm (CAMI: d = 0.22 RIBS: d = 0.21; n = 237). Seminar had the strongest and relatively stable effect on students' attitudes and intended behaviour, but the effect of short video interventions was also considerable and stable over time. Since short effective video interventions are relatively cheap, conveniently accessible and easy to disseminate globally, we recommend them for further research and development.

Repeatability of short-duration transient visual evoked potentials in normal subjects.

PubMed

Tello, Celso; De Moraes, Carlos Gustavo V; Prata, Tiago S; Derr, Peter; Patel, Jayson; Siegfried, John; Liebmann, Jeffrey M; Ritch, Robert

2010-06-01

To evaluate the within-session and inter-session repeatability of a new, short-duration transient visual evoked potential (SD-tVEP) device on normal individuals, we tested 30 normal subjects (20/20 visual acuity, normal 24-2 SITA Standard VF) with SD-tVEP. Ten of these subjects had their tests repeated within 1-2 months from the initial visit. Synchronized single-channel EEG was recorded using a modified Diopsys Enfant System (Diopsys, Inc., Pine Brook, New Jersey, USA). A checkerboard stimulus was modulated at two reversals per second. Two different contrasts of checkerboard reversal patterns were used: 85% Michelson contrast with a mean luminance of 66.25 cd/m(2) and 10% Michelson contrast with a mean luminance of 112 cd/m(2). Each test lasted 20 s. Both eyes, independently and together, were tested 10 times (5 times at each contrast level). The following information was identified from the filtered N75-P100-N135 complex: N75 amplitude, N75 latency, P100 amplitude, P100 latency, and Delta Amplitude (N75-P100). The median values for each eye's five SD-tVEP parameters were calculated and grouped into two data sets based on contrast level. Mean age was 27.3 +/- 5.2 years. For OD only, the median (95% confidence intervals) of Delta Amplitude (N75-P100) amplitudes at 10% and 85% contrast were 4.6 uV (4.1-5.9) and 7.1 uV (5.15-9.31). The median P100 latencies were 115.2 ms (112.0-117.7) and 104.0 ms (99.9-106.0). There was little within-session variability for any of these parameters. Intraclass correlation coefficients ranged between 0.64 and 0.98, and within subject coefficients of variation were 3-5% (P100 latency) and 15-30% (Delta Amplitude (N75-P100) amplitude). Bland-Altman plots showed good agreement between the first and fifth test sessions (85% contrast Delta Amplitude (N75-P100) delta amplitude, mean difference, 0.48 mV, 95% CI, -0.18-1.12; 85% contrast P100 latency delay, -0.82 ms, 95% CI, -3.12-1.46; 10% contrast Delta Amplitude (N75-P100) amplitude, 0

Sleep Complaints in Older Blacks: Do Demographic and Health Indices Explain Poor Sleep Quality and Duration?

PubMed Central

Gamaldo, Alyssa A.; Gamaldo, Charlene E.; Allaire, Jason C.; Aiken-Morgan, Adrienne T.; Salas, Rachel E.; Szanton, Sarah; Whitfield, Keith E.

2014-01-01

Objective: To examine the relationship between measures of sleep quality and the presence of commonly encountered comorbid and sociodemographic conditions in elderly Black subjects. Method: Analyses included participants from the Baltimore Study of Black Aging (BSBA; n = 450; mean age 71.43 years; SD 9.21). Pittsburgh Sleep Quality Index (PSQI) measured overall sleep pattern and quality. Self-reported and objective measures of physical and mental health data and demographic information were collected for all participants. Results: Sociodemographic and comorbid health factors were significantly associated with sleep quality. Results from regression analyses revealed that older age, current financial strain, interpersonal problems, and stress were unique predictors of worse sleep quality. Sleep duration was significantly correlated with age, depressive affect, interpersonal problems, and stress; only age was a unique significant predictor. While participants 62 years or younger had worse sleep quality with increasing levels of stress, there was no significant relationship between sleep quality and stress for participants 81 years and older. Conclusions: Several potential mechanisms may explain poor sleep in urban, community dwelling Blacks. Perceived stressors, including current financial hardship or hardship experienced for an extended time period throughout the lifespan, may influence sleep later in life. Citation: Gamaldo AA, Gamaldo CE, Allaire JC, Aiken-Morgan AT, Salas RE, Szanton S, Whitfield KE. Sleep complaints in older blacks: do demographic and health indices explain poor sleep quality and duration? J Clin Sleep Med 2014;10(7):725-731. PMID:25024649

Seasonal and diurnal analysis of NO2 concentrations from a long-duration study conducted in Las Vegas, Nevada

EPA Science Inventory

A study, conducted in Las Vegas, NV from mid-December 2008 to mid-December 2009 along an interstate highway, collected continuous and integrated ambient air quality samples for a wide variety of species including NO2 and NOX. Previous near-road studies have been short duration, ...

Does selection for short sleep duration explain human vulnerability to Alzheimer's disease?

PubMed

Nesse, Randolph M; Finch, Caleb E; Nunn, Charles L

2017-01-16

Compared with other primates, humans sleep less and have a much higher prevalence of Alzheimer 's disease (AD) pathology. This article reviews evidence relevant to the hypothesis that natural selection for shorter sleep time in humans has compromised the efficacy of physiological mechanisms that protect against AD during sleep. In particular, the glymphatic system drains interstitial fluid from the brain, removing extra-cellular amyloid beta (eAβ) twice as fast during sleep. In addition, melatonin - a peptide hormone that increases markedly during sleep - is an effective antioxidant that inhibits the polymerization of soluble eAβ into insoluble amyloid fibrils that are associated with AD. Sleep deprivation increases plaque formation and AD, which itself disrupts sleep, potentially creating a positive feedback cycle. These and other physiological benefits of sleep may be compromised by short sleep durations. Our hypothesis highlights possible long-term side effects of medications that reduce sleep, and may lead to potential new strategies for preventing and treating AD. © The Author(s) 2017. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

Parenteral nutrition in short bowel syndrome patients, regardless of its duration, increases serum proinflammatory cytokines.

PubMed

Bizari, Letícia; da Silva Santos, Andressa Feijó; Foss, Norma Tiraboschi; Marchini, Júlio Sérgio; Suen, Vivian Marques Miguel

2016-07-01

Short bowel syndrome is a severe malabsorption disorder, and prolonged parenteral nutrition is essential for survival in some cases. Among the undesirable effects of long-term parenteral nutrition is an increase in proinflammatory cytokines. The aim of the present study was to measure the serum levels of interleukin-6, interleukin-10, tumor necrosis factor alpha, and transforming growth factor beta, in patients with short bowel syndrome on cyclic parenteral nutrition and patients who had previously received but no longer require parenteral nutrition. The study was cross-sectional and observational. Three groups were studied as follows: Parenteral nutrition group, 9 patients with short bowel syndrome that receive cyclic parenteral nutrition; Oral nutrition group, 10 patients with the same syndrome who had been weaned off parenteral nutrition for at least 1 year prior to the study; Control group, 13 healthy adults, matched for age and sex to parenteral and oral groups. The following data were collected: age, tobacco use, drug therapies, dietary intake, body weight, height, blood collection. All interleukins were significantly higher in the parenteral group compared with the control group as follows: interleukin-6: 22 ± 19 vs 1.5 ± 1.4 pg/mL, P= .0002; transforming growth factor β: 854 ± 204 vs 607 ± 280 pg/mL, P= .04; interleukin-10: 8 ± 37 vs 0.6 ± 4, P= .03; tumor necrosis factor α: 20 ± 8 vs 8 ± 4 pg/mL, P< .0001. We concluded that parenteral nutrition in short bowel syndrome patients, regardless of its duration, increases serum proinflammatory cytokines. Copyright © 2016 Elsevier Inc. All rights reserved.

Self-reported Napping, Sleep Duration and Quality in the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) Study

PubMed Central

Picarsic, Jennifer L.; Glynn, Nancy W.; Taylor, Christopher A.; Katula, Jeffery; Goldman, Suzanne E.; Studenski, Stephanie; Newman, Anne B.

2010-01-01

OBJECTIVES To determine the prevalence of self-reported napping and its association with subjective nighttime sleep duration and quality, as measured by sleep-onset latency and sleep efficiency. DESIGN Cross-sectional study. SETTING Lifestyle Interventions and Independence for Elder’s Pilot Study. PARTICIPANTS Community-dwelling older adults (N=414), aged 70 to 89 years. MEASUREMENTS Self-report questionnaire on napping and sleep, derived from the Pittsburgh Sleep Quality Index (PSQI) scale. RESULTS A total of 54 percent of participants reported napping with mean nap duration of 55 minutes, (SD 41.2 minutes). Compared to non-nappers, nappers were more often men (37.3% vs. 23.8%, P = .003), African American (20.4% vs.14.4%, P = .06), or diabetic (28% vs. 14.3%, P = .007). Nappers and non-nappers had similar nighttime sleep duration and quality, but nappers spent about 10 percent of their 24-hour sleep occupied in napping. In a multivariate model, the odds of napping were higher for diabetics (OR: 1.9; 95% CI: 1.2–3.0) and men (OR: 1.9; 95% CI: 1.2–3.0)). In nappers, diabetes mellitus (β = 12.3 minutes, P =.005), male gender (β = 9.0 minutes, P = .04), higher BMI (β = 0.8 minutes, P = .02), and lower MMSE (β = 2.2, P = .03) were independently associated with longer nap duration. CONCLUSION Napping was a common practice in community-dwelling older adults and did not detract from nighttime sleep duration or quality. Given its high prevalence and association with diabetes, napping behavior should be assessed as part of sleep behavior, both in future research and in clinical practice. PMID:18662202

Self-reported napping and duration and quality of sleep in the lifestyle interventions and independence for elders pilot study.

PubMed

Picarsic, Jennifer L; Glynn, Nancy W; Taylor, Christopher A; Katula, Jeffrey A; Goldman, Suzanne E; Studenski, Stephanie A; Newman, Anne B

2008-09-01

To determine the prevalence of self-reported napping and its association with subjective nighttime sleep duration and quality, as measured according to sleep-onset latency and sleep efficiency. Cross-sectional study. Lifestyle Interventions and Independence for Elders Pilot Study. Community-dwelling older adults (N=414) aged 70 to 89. Self-report questionnaire on napping and sleep derived from the Pittsburgh Sleep Quality Index (PSQI) scale. Fifty-four percent of participants reported napping, with mean nap duration of 55.0+/-41.2 minutes. Nappers were more likely to be male (37.3% vs 23.8%, P=.003) and African American (20.4% vs 14.4%, P=.06) and to have diabetes mellitus (28% vs 14.3%, P=.007) than non-nappers. Nappers and non-nappers had similar nighttime sleep duration and quality, but nappers spent approximately 10% of their 24-hour sleep occupied in napping. In a multivariate model, the odds of napping were higher for subjects with diabetes mellitus (odds ratio (OR)=1.9, 95% confidence interval (CI)=1.2-3.0) and men (OR=1.9, 95% CI=1.2-3.0). In nappers, diabetes mellitus (beta=12.3 minutes, P=.005), male sex (beta=9.0 minutes, P=.04), higher body mass index (beta=0.8 minutes, P=.02), and lower Mini-Mental State Examination score (beta=2.2 minutes, P=.03) were independently associated with longer nap duration. Napping was a common practice in community-dwelling older adults and did not detract from nighttime sleep duration or quality. Given its high prevalence and association with diabetes mellitus, napping behavior should be assessed as part of sleep behavior in future research and in clinical practice.

Short versus prolonged dual antiplatelet therapy (DAPT) duration after coronary stent implantation: A comparison between the DAPT study and 9 other trials evaluating DAPT duration

PubMed Central

Toyota, Toshiaki; Shiomi, Hiroki; Morimoto, Takeshi; Natsuaki, Masahiro; Kimura, Takeshi

2017-01-01

Aims The Dual Antiplatelet Therapy (DAPT) study demonstrated that DAPT beyond 1-year after drug-eluting stent (DES) implantation, as compared with aspirin therapy alone, significantly reduced the risk of major cardiovascular and cerebrovascular events, which was mainly driven by the large risk reduction for myocardial infarction (MI). We sought to compare the largest DAPT study with other trials evaluating DAPT durations after DES implantation. Methods and results By a systematic literature search, we identified 9 trials comparing prolonged- versus short-DAPT in addition to the DAPT study. The result from the DAPT study (N = 9961) with public–private collaboration was different from the pooled result of the 9 other investigator-driven trials (N = 22174) in terms of the effect of prolonged-DAPT on MI (odds ratio [OR] 0.48 [95%CI 0.38–0.62] versus pooled OR 0.88 [95%CI 0.67–1.15]: P = 0.001 for difference), while the trends for excess risk of prolonged-DAPT relative to short-DAPT for all-cause death (OR 1.31 [95%CI 0.97–1.78] versus pooled OR 1.16 [95%CI 0.92–1.45]: P = 0.53 for difference), and bleeding (OR 1.62 [95%CI 1.21–2.17] versus pooled OR 2.08 [95%CI 1.51–2.84]: P = 0.25 for difference) were consistently seen in both the DAPT and other trials. The annual rate of MI during aspirin mono-therapy in the DAPT study was much higher than that those in the other trials (2.7% versus 0.6–1.6%). Conclusions Given the difference between the DAPT study and other trials, future studies should focus on certain subgroups of patients that are more or less likely to benefit from longer duration DAPT. PMID:28931015

Short versus prolonged dual antiplatelet therapy (DAPT) duration after coronary stent implantation: A comparison between the DAPT study and 9 other trials evaluating DAPT duration.

PubMed

Toyota, Toshiaki; Shiomi, Hiroki; Morimoto, Takeshi; Natsuaki, Masahiro; Kimura, Takeshi

2017-01-01

The Dual Antiplatelet Therapy (DAPT) study demonstrated that DAPT beyond 1-year after drug-eluting stent (DES) implantation, as compared with aspirin therapy alone, significantly reduced the risk of major cardiovascular and cerebrovascular events, which was mainly driven by the large risk reduction for myocardial infarction (MI). We sought to compare the largest DAPT study with other trials evaluating DAPT durations after DES implantation. By a systematic literature search, we identified 9 trials comparing prolonged- versus short-DAPT in addition to the DAPT study. The result from the DAPT study (N = 9961) with public-private collaboration was different from the pooled result of the 9 other investigator-driven trials (N = 22174) in terms of the effect of prolonged-DAPT on MI (odds ratio [OR] 0.48 [95%CI 0.38-0.62] versus pooled OR 0.88 [95%CI 0.67-1.15]: P = 0.001 for difference), while the trends for excess risk of prolonged-DAPT relative to short-DAPT for all-cause death (OR 1.31 [95%CI 0.97-1.78] versus pooled OR 1.16 [95%CI 0.92-1.45]: P = 0.53 for difference), and bleeding (OR 1.62 [95%CI 1.21-2.17] versus pooled OR 2.08 [95%CI 1.51-2.84]: P = 0.25 for difference) were consistently seen in both the DAPT and other trials. The annual rate of MI during aspirin mono-therapy in the DAPT study was much higher than that those in the other trials (2.7% versus 0.6-1.6%). Given the difference between the DAPT study and other trials, future studies should focus on certain subgroups of patients that are more or less likely to benefit from longer duration DAPT.

Bidirectional Associations between Sleep (Quality and Duration) and Psychosocial Functioning across the University Years

ERIC Educational Resources Information Center

Tavernier, Royette; Willoughby, Teena

2014-01-01

Despite extensive research on sleep and psychosocial functioning, an important gap within the literature is the lack of inquiry into the direction of effects between these 2 constructs. The purpose of the present 3-year longitudinal study was to examine bidirectional associations between sleep (quality and duration) and 3 indices of psychosocial…

QSRA: a quality-value guided de novo short read assembler.

PubMed

Bryant, Douglas W; Wong, Weng-Keen; Mockler, Todd C

2009-02-24

New rapid high-throughput sequencing technologies have sparked the creation of a new class of assembler. Since all high-throughput sequencing platforms incorporate errors in their output, short-read assemblers must be designed to account for this error while utilizing all available data. We have designed and implemented an assembler, Quality-value guided Short Read Assembler, created to take advantage of quality-value scores as a further method of dealing with error. Compared to previous published algorithms, our assembler shows significant improvements not only in speed but also in output quality. QSRA generally produced the highest genomic coverage, while being faster than VCAKE. QSRA is extremely competitive in its longest contig and N50/N80 contig lengths, producing results of similar quality to those of EDENA and VELVET. QSRA provides a step closer to the goal of de novo assembly of complex genomes, improving upon the original VCAKE algorithm by not only drastically reducing runtimes but also increasing the viability of the assembly algorithm through further error handling capabilities.

The Nervous Flyer: Nerves, Flying and the First World War.

PubMed

Shaw Cobden, Lynsey

2018-02-02

This is not an article about 'shell-shock'. It explores the military medical response to nervous disorders in the Royal Flying Corps. The First World War exposed the propensity of pilots to the nervous and psychological rigours of aerial warfare, but their unique experiences have been overlooked in favour of 'trauma' in infantrymen. This represents a critical lacuna in the historiography of military medicine, for flying personnel were studied apart from 'shell-shocked' soldiers. This article will show that flyers were believed to be medically different, and what set them apart from men in the trenches was their unique employment. The war necessitated, and provided the conditions for, the study of the medical problems of flying, including the significant nervous strains. Medical officers quickly established that flying not only affected bodily functions, but also 'wore down' the nerves that regulated psychological responses. This article will therefore present the medical view. It will study the research of air-minded medical officers and the conclusions reached on the nervous disorders of flying personnel.

Experiments on 1,000 km/s flyer acceleration and collisions

NASA Astrophysics Data System (ADS)

Karasik, Max; Weaver, J. L.; Aglitskiy, Y.; Kehne, D. M.; Zalesak, S. T.; Velikovich, A. L.; Oh, J.; Serlin, V.; Obenschain, S. P.

2012-10-01

We will present results from follow-on experiments to the record-high velocities achieved using the ultra-uniform deep-uv drive of the Nike KrF laser [Karasik et al, Phys. Plasmas 17, 056317 (2010)], in which highly accelerated planar foils of deuterated polystyrene were made to collide with a witness foil to produce ˜1 Gbar shock pressures and result in heating of matter to thermonuclear temperatures. Such velocities may indicate a path to lower minimum energy required for central ignition. Still higher velocities and higher target densities are required for impact fast ignition. New results give velocity of >1,100 km/s achieved through improvements in pulseshaping. Variation of second foil parameters results in significant change in fusion neutron production on impact. In-flight target density is inferred from target heating upon collision via DD neutron time-of-flight ion temperature measurement. Availability of pressures generated by collisions of such highly accelerated flyers may provide an experimental platform for study of matter at extreme conditions. Work is supported by US DOE (NNSA).

Effects of sleep timing, sleep quality and sleep duration on school achievement in adolescents.

PubMed

Tonetti, Lorenzo; Fabbri, Marco; Filardi, Marco; Martoni, Monica; Natale, Vincenzo

2015-08-01

The aim of this study was to examine the effects of sleep timing, quality and duration on school achievement in adolescents. Thirty-six Italian students (mean age: 18.14 ± 0.49 years) attending their last year of high school participated in the study. They completed the Morningness-Eveningness Questionnaire for Children and Adolescents (MEQ-CA). This was used to determine their ideal sleep timing by computing the total score, with higher scores corresponding to a greater tendency toward morningness. In addition, students underwent two non-consecutive weeks of actigraphy in one-month period to objectively assess: habitual sleep timing through the midpoint of sleep (MS); habitual sleep quality through the parameter of sleep efficiency (SE); and habitual sleep duration through the parameter of total sleep time (TST). Participants also completed the Mini Sleep Questionnaire, which allowed us to assess perceived sleep quality, at the end of each actigraphic-recording week. School performance was assessed using the grades obtained by students in their school leaving exams taken at the end of the school year. A significant positive correlation was observed between SE and exam grades, as well as MEQ-CA scores and grades. Multiple regression analysis showed that only SE was significantly and positively related to the final grade. Examining objective and ecological measures, SE (indicator of sleep quality) had the strongest effect on school achievement in adolescents. Copyright © 2015 Elsevier B.V. All rights reserved.

Relationship Between Short Sleep Duration and Preseason Concussion Testing.

PubMed

Silverberg, Noah D; Berkner, Paul D; Atkins, Joseph E; Zafonte, Ross; Iverson, Grant L

2016-05-01

Baseline, preseason assessment of cognition, symptoms, and balance has been recommended as part of a comprehensive sport concussion management program. We examined the relationship between sleep and baseline test results. We hypothesized that adolescents who slept fewer hours the night before would report more symptoms and perform more poorly on cognitive testing than students who had a full night sleep. Cross-sectional observation study. Preseason concussion testing for high school athletes. A large sample (n = 2928) of student athletes from Maine, USA, between the ages of 13 and 18 years completed preseason testing. Participants with developmental problems, a history of treatment for neurological or psychiatric problems, recent concussion, or 3 or more prior concussions were excluded. Athletes were divided into 4 groups based on their sleep duration the night before testing. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT; ImPACT Applications, Inc, Pittsburgh, PA) cognitive composite scores and the embedded Post-Concussion Symptom Scale. Sleep was not related to any ImPACT cognitive composite score, after covarying for age and controlling for multiple comparisons. In contrast, there were sleep duration, sex, and sleep duration by sex effects on the Post-Concussion Symptom Scale. The effect of sleep duration on symptom reporting was more pronounced in girls. Supplementary analyses suggested that sleep insufficiency was associated with a diverse array of postconcussion-like symptoms. Poor sleep the night before baseline or postinjury testing may be an important confound when assessing postconcussion symptoms. Girls may be more vulnerable to experiencing and reporting symptoms following insufficient sleep. Clinicians should routinely ask how the athlete slept the night before preseason baseline testing and consider deferring the symptom assessment or later retesting athletes who slept poorly.

High-intensity exercise of short duration alters bovine bone density and shape.

PubMed

Hiney, K M; Nielsen, B D; Rosenstein, D; Orth, M W; Marks, B P

2004-06-01

The ability of short-duration high-intensity exercise to stimulate bone formation in confinement was investigated using immature Holstein bull calves as a model. Eighteen bull calves, 8 wk of age, were assigned to one of three treatment groups: 1) group-housed (GR, which served as a control), 2) confined with no exercise (CF), or 3) confined with exercise (EX). The exercise protocol consisted of running 50 m on a concrete surface once daily, 5 d/wk. Confined calves remained stalled for the 42-d duration of the trial. Blood samples were taken to analyze concentrations of osteocalcin and deoxypyridinoline, markers of bone formation and resorption. At the completion of the trial, calves were humanely killed, and both forelegs were collected. The fused third and fourth metacarpal bone was scanned using computed tomography for determination of cross-sectional geometry and bone mineral density. Three-point bending tests to failure were performed on metacarpal bones. The exercise protocol resulted in the formation of a rounder bone in EX as well as in increased dorsal cortex thickness compared with those in the GR and CF. The exercised calves had a significantly smaller medullary cavity than CF and GR (P < 0.01) and a larger percentage of cortical bone area than CF (P < 0.01). Dorsal, palmar, and total bone mineral density was greater in EX than in CF (P < 0.05), and palmar and total bone mineral densities were greater (P < 0.05) in EX than in GR. There was a trend for the bones of EX to have a higher fracture force than CF (P < 0.10). Osteocalcin concentrations normalized from d 0 were higher in EX than CF (P < 0.05). Therefore, the exercise protocol altered bone shape and seemed to increase bone formation comparison with the stalled and group-housed calves.

Transcriptional Signatures of Sleep Duration Discordance in Monozygotic Twins.

PubMed

Watson, N F; Buchwald, D; Delrow, J J; Altemeier, W A; Vitiello, M V; Pack, A I; Bamshad, M; Noonan, C; Gharib, S A

2017-01-01

Habitual short sleep duration is associated with adverse metabolic, cardiovascular, and inflammatory effects. Co-twin study methodologies account for familial (eg, genetics and shared environmental) confounding, allowing assessment of subtle environmental effects, such as the effect of habitual short sleep duration on gene expression. Therefore, we investigated gene expression in monozygotic twins discordant for actigraphically phenotyped habitual sleep duration. Eleven healthy monozygotic twin pairs (82% female; mean age 42.7 years; SD = 18.1), selected based on subjective sleep duration discordance, were objectively phenotyped for habitual sleep duration with 2 weeks of wrist actigraphy. Peripheral blood leukocyte (PBL) RNA from fasting blood samples was obtained on the final day of actigraphic measurement and hybridized to Illumina humanHT-12 microarrays. Differential gene expression was determined between paired samples and mapped to functional categories using Gene Ontology. Finally, a more comprehensive gene set enrichment analysis was performed based on the entire PBL transcriptome. The mean 24-hour sleep duration of the total sample was 439.2 minutes (SD = 46.8 minutes; range 325.4-521.6 minutes). Mean within-pair sleep duration difference per 24 hours was 64.4 minutes (SD = 21.2; range 45.9-114.6 minutes). The twin cohort displayed distinctive pathway enrichment based on sleep duration differences. Habitual short sleep was associated with up-regulation of genes involved in transcription, ribosome, translation, and oxidative phosphorylation. Unexpectedly, genes down-regulated in short sleep twins were highly enriched in immuno-inflammatory pathways such as interleukin signaling and leukocyte activation, as well as developmental programs, coagulation cascade, and cell adhesion. Objectively assessed habitual sleep duration in monozygotic twin pairs appears to be associated with distinct patterns of differential gene expression and pathway enrichment. By

Does selection for short sleep duration explain human vulnerability to Alzheimer’s disease?

PubMed Central

Nesse, Randolph M; Finch, Caleb E; Nunn, Charles L

2017-01-01

Abstract Compared with other primates, humans sleep less and have a much higher prevalence of Alzheimer ’s disease (AD) pathology. This article reviews evidence relevant to the hypothesis that natural selection for shorter sleep time in humans has compromised the efficacy of physiological mechanisms that protect against AD during sleep. In particular, the glymphatic system drains interstitial fluid from the brain, removing extra-cellular amyloid beta (eAβ) twice as fast during sleep. In addition, melatonin—a peptide hormone that increases markedly during sleep—is an effective antioxidant that inhibits the polymerization of soluble eAβ into insoluble amyloid fibrils that are associated with AD. Sleep deprivation increases plaque formation and AD, which itself disrupts sleep, potentially creating a positive feedback cycle. These and other physiological benefits of sleep may be compromised by short sleep durations. Our hypothesis highlights possible long-term side effects of medications that reduce sleep, and may lead to potential new strategies for preventing and treating AD. PMID:28096295

A SIZE-DURATION TREND FOR GAMMA-RAY BURST PROGENITORS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnacka, Anna; Loeb, Abraham, E-mail: abarnacka@cfa.harvard.edu, E-mail: aloeb@cfa.harvard.edu

2014-10-10

Gamma-ray bursts (GRBs) show a bimodal distribution of durations, separated at a duration of ∼2 s. Observations have confirmed the association of long GRBs with the collapse of massive stars. The origin of short GRBs is still being explored. We examine constraints on the size of emission regions in short and long GRBs detected by Fermi/GBM. We find that the transverse extent of emission regions during the prompt phase, R, and the burst duration, T {sub 90}, are consistent with the relation R ∼ c × T {sub 90}, for both long and short GRBs. We find the characteristic transverse extentmore » for the prompt emission region to be ∼2 × 10{sup 10} cm and ∼4 × 10{sup 11} cm for short and long GRBs, respectively.« less

SPHERES and Astrobee: Space Station Robotic Free Flyers

NASA Technical Reports Server (NTRS)

Benavides, Jose V.

2017-01-01

Free-flying space robots can be used when humans are present to off-load routine work, to increase astronaut productivity, and to handle contingencies. The International Space Station (ISS), for example, is a continuously manned orbital laboratory the size of a large house, which contains many thousands of inventory items and hundreds of diverse payloads and experiments - all of which have to be managed by 6 person crew. To help with this, NASA is developing and testing robotic free-flyers on the ISS. SPHERES (Synchronized Position Hold, Engage, Reorient, Experimental Satellites) is an ISS facility with three nano-satellites designed to research estimation, control, and autonomy algorithms. SPHERES are volleyball-sized, have their own power, propulsion and navigation systems, and work on the ISS under astronaut supervision. For more than 10 years, NASA has made SPHERES available to other U.S. government agencies, schools, commercial companies and students as a platform for science, technology development, and education. SPHERES will soon be succeeded by the new Astrobee free-flying robot. Astrobee builds on the success of SPHERES, but in addition to research, the robot will also be used for housekeeping and monitoring duties without astronaut supervision. Astrobee makes extensive use of open-source (the complete software stack is available on GitHub) and is scheduled to be installed on the ISS in late Spring 2018.

RFI flagging implications for short-duration transients

NASA Astrophysics Data System (ADS)

Cendes, Y.; Prasad, P.; Rowlinson, A.; Wijers, R. A. M. J.; Swinbank, J. D.; Law, C. J.; van der Horst, A. J.; Carbone, D.; Broderick, J. W.; Staley, T. D.; Stewart, A. J.; Huizinga, F.; Molenaar, G.; Alexov, A.; Bell, M. E.; Coenen, T.; Corbel, S.; Eislöffel, J.; Fender, R.; Grießmeier, J.-M.; Jonker, P.; Kramer, M.; Kuniyoshi, M.; Pietka, M.; Stappers, B.; Wise, M.; Zarka, P.

2018-04-01

With their wide fields of view and often relatively long coverage of any position in the sky in imaging survey mode, modern radio telescopes provide a data stream that is naturally suited to searching for rare transients. However, Radio Frequency Interference (RFI) can show up in the data stream in similar ways to such transients, and thus the normal pre-treatment of filtering RFI (flagging) may also remove astrophysical transients from the data stream before imaging. In this paper we investigate how standard flagging affects the detectability of such transients by examining the case of transient detection in an observing mode used for Low Frequency Array (LOFAR; van Haarlem et al., 2013) surveys. We quantify the fluence range of transients that would be detected, and the reduction of their SNR due to partial flagging. We find that transients with a duration close to the integration sampling time, as well as bright transients with durations on the order of tens of seconds, are completely flagged. For longer transients on the order of several tens of seconds to minutes, the flagging effects are not as severe, although part of the signal is lost. For these transients, we present a modified flagging strategy which mitigates the effect of flagging on transient signals. We also present a script which uses the differences between the two strategies, and known differences between transient RFI and astrophysical transients, to notify the observer when a potential transient is in the data stream.

Search for transient gravitational waves in coincidence with short-duration radio transients during 2007-2013

NASA Astrophysics Data System (ADS)

Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Behnke, B.; Bejger, M.; Bell, A. S.; Bell, C. J.; Berger, B. K.; Bergman, J.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birney, R.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bohe, A.; Bojtos, P.; Bond, C.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brown, N. M.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, H. Y.; Chen, Y.; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, S.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dattilo, V.; Dave, I.; Daveloza, H. P.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; DeBra, D.; Debreczeni, G.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dojcinoski, G.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etzel, T.; Evans, M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M.; Fournier, J.-D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gaur, G.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gordon, N. A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Hall, B. R.; Hall, E. D.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Hofman, D.; Hollitt, S. E.; Holt, K.; Holz, D. E.; Hopkins, P.; Hosken, D. J.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Idrisy, A.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J.-M.; Isi, M.; Islas, G.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jiménez-Forteza, F.; Johnson, W. W.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; Haris, K.; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Karki, S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kawazoe, F.; Kéfélian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.; Key, J. S.; Khalaidovski, A.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chunglee; Kim, J.; Kim, K.; Kim, Nam-Gyu; Kim, Namjun; Kim, Y.-M.; King, E. J.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Kokeyama, K.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Królak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Levine, B. M.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Logue, J.; Lombardi, A. L.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lück, H.; Lundgren, A. P.; Luo, J.; Lynch, R.; Ma, Y.; MacDonald, T.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Magee, R. M.; Mageswaran, M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martin, R. M.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B. C.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, K. N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P. G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Necula, V.; Nedkova, K.; Nelemans, G.; Neri, M.; Neunzert, A.; Newton, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ott, C. D.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Pereira, R.; Perreca, A.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Premachandra, S. S.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Ricci, F.; Riles, K.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, J. D.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O. E. S.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sentenac, D.; Sequino, V.; Sergeev, A.; Serna, G.; Setyawati, Y.; Sevigny, A.; Shaddock, D. A.; Shahriar, M. S.; Shaltev, M.; Shao, Z.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, A. D.; Simakov, D.; Singer, A.; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, J. R.; Smith, N. D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stiles, D.; Stone, R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tápai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Tomlinson, C.; Tonelli, M.; Torres, C. V.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifirò, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Welborn, T.; Wen, L.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D. J.; Whiting, B. F.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Worden, J.; Wright, J. L.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, H.; Yvert, M.; ZadroŻny, A.; Zangrando, L.; Zanolin, M.; Zendri, J.-P.; Zevin, M.; Zhang, F.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.; Zweizig, J.; Archibald, A. M.; Banaszak, S.; Berndsen, A.; Boyles, J.; Cardoso, R. F.; Chawla, P.; Cherry, A.; Dartez, L. P.; Day, D.; Epstein, C. R.; Ford, A. J.; Flanigan, J.; Garcia, A.; Hessels, J. W. T.; Hinojosa, J.; Jenet, F. A.; Karako-Argaman, C.; Kaspi, V. M.; Keane, E. F.; Kondratiev, V. I.; Kramer, M.; Leake, S.; Lorimer, D.; Lunsford, G.; Lynch, R. S.; Martinez, J. G.; Mata, A.; McLaughlin, M. A.; McPhee, C. A.; Penucci, T.; Ransom, S.; Roberts, M. S. E.; Rohr, M. D. W.; Stairs, I. H.; Stovall, K.; van Leeuwen, J.; Walker, A. N.; Wells, B. L.; LIGO Scientific Collaboration; Virgo Collaboration

2016-06-01

We present an archival search for transient gravitational-wave bursts in coincidence with 27 single-pulse triggers from Green Bank Telescope pulsar surveys, using the LIGO, Virgo, and GEO interferometer network. We also discuss a check for gravitational-wave signals in coincidence with Parkes fast radio bursts using similar methods. Data analyzed in these searches were collected between 2007 and 2013. Possible sources of emission of both short-duration radio signals and transient gravitational-wave emission include starquakes on neutron stars, binary coalescence of neutron stars, and cosmic string cusps. While no evidence for gravitational-wave emission in coincidence with these radio transients was found, the current analysis serves as a prototype for similar future searches using more sensitive second-generation interferometers.

Short-duration solar microwave bursts and associated soft X-ray emission. M.S. Thesis

NASA Technical Reports Server (NTRS)

Spangler, S. R.

1972-01-01

Two hundred and fifty-nine short-duration microwave (15.4 GHz) bursts which occurred during the period of January 1968 to March 1970 were correlated with possible soft X-ray (2-12 A) flares occurring simultaneously. Sixty-six percent of the microwave bursts which were observed during periods of soft X-ray data coverage had associated soft X-ray flares. A study of an index of impulsiveness of the microwave flares failed to show a separation of the events into subclasses which could be attributed to distinctly different physical mechanisms. A weak (0.43) correlation was found between the intensities of the microwave and X-ray flares. A very weak (0.15) and statistically questionable correlation was found between the total energy released in these two energy ranges. Two models for the electron acceleration mechanism are discussed.

Cellular aging and restorative processes: subjective sleep quality and duration moderate the association between age and telomere length in a sample of middle-aged and older adults.

PubMed

Cribbet, Matthew R; Carlisle, McKenzie; Cawthon, Richard M; Uchino, Bert N; Williams, Paula G; Smith, Timothy W; Gunn, Heather E; Light, Kathleen C

2014-01-01

To examine whether subjective sleep quality and sleep duration moderate the association between age and telomere length (TL). Participants completed a demographic and sleep quality questionnaire, followed by a blood draw. Social Neuroscience Laboratory. One hundred fifty-four middle-aged to older adults (age 45-77 y) participated. Participants were excluded if they were on immunosuppressive treatment and/or had a disease with a clear immunologic (e.g., cancer) component. N/A. Subjective sleep quality and sleep duration were assessed using the Pittsburgh Sleep Quality Index (PSQI) and TL was determined using peripheral blood mononuclear cells (PBMCs). There was a significant first-order negative association between age and TL. Age was also negatively associated with the self-reported sleep quality item and sleep duration component of the PSQI. A significant age × self-reported sleep quality interaction revealed that age was more strongly related to TL among poor sleepers, and that good sleep quality attenuated the association between age and TL. Moreover, adequate subjective sleep duration among older adults (i.e. greater than 7 h per night) was associated with TL comparable to that in middle-aged adults, whereas sleep duration was unrelated to TL for the middle-aged adults in our study. The current study provides evidence for an association between sleep quality, sleep duration, and cellular aging. Among older adults, better subjective sleep quality was associated with the extent of cellular aging, suggesting that sleep duration and sleep quality may be added to a growing list of modifiable behaviors associated with the adverse effects of aging.

Accurate estimation of short read mapping quality for next-generation genome sequencing

PubMed Central

Ruffalo, Matthew; Koyutürk, Mehmet; Ray, Soumya; LaFramboise, Thomas

2012-01-01

Motivation: Several software tools specialize in the alignment of short next-generation sequencing reads to a reference sequence. Some of these tools report a mapping quality score for each alignment—in principle, this quality score tells researchers the likelihood that the alignment is correct. However, the reported mapping quality often correlates weakly with actual accuracy and the qualities of many mappings are underestimated, encouraging the researchers to discard correct mappings. Further, these low-quality mappings tend to correlate with variations in the genome (both single nucleotide and structural), and such mappings are important in accurately identifying genomic variants. Approach: We develop a machine learning tool, LoQuM (LOgistic regression tool for calibrating the Quality of short read mappings, to assign reliable mapping quality scores to mappings of Illumina reads returned by any alignment tool. LoQuM uses statistics on the read (base quality scores reported by the sequencer) and the alignment (number of matches, mismatches and deletions, mapping quality score returned by the alignment tool, if available, and number of mappings) as features for classification and uses simulated reads to learn a logistic regression model that relates these features to actual mapping quality. Results: We test the predictions of LoQuM on an independent dataset generated by the ART short read simulation software and observe that LoQuM can ‘resurrect’ many mappings that are assigned zero quality scores by the alignment tools and are therefore likely to be discarded by researchers. We also observe that the recalibration of mapping quality scores greatly enhances the precision of called single nucleotide polymorphisms. Availability: LoQuM is available as open source at http://compbio.case.edu/loqum/. Contact: matthew.ruffalo@case.edu. PMID:22962451

Short communication: Microbial quality of raw milk following commercial long-distance hauling.

PubMed

Darchuk, Emily M; Meunier-Goddik, Lisbeth; Waite-Cusic, Joy

2015-12-01

Hauling is a critical part of the commercial milk supply chain, yet very few studies have aimed to understand its effect on raw milk quality. This study focused on the effect of extended-duration tanker use during hauling on raw milk quality at a commercial facility. Standard tanker use [cleaned-in-place (CIP) once per 24h] served as a control and an incremental between-load water rinse with sanitizer treatment (RS) was evaluated to mitigate any effect from extended duration hauling. During this study, 1 commercial truck with 2 trailers was monitored for 10d. The truck collected milk at a large dairy farm, transported the milk to a manufacturing facility, and then returned to the same farm for a second load. Each round-trip journey took between 10 and 12h, allowing for 2 loads per 24-h use period. Following the second delivery, the truck was cleaned by CIP treatment starting a new treatment day. Producer samples were collected from the raw milk bulk tank on the farm before loading milk into the tanker. The same milk was sampled directly out of the tanker truck before unloading at the manufacturer. Effect on individual bacteria count, thermophilic spore count, and preliminary incubation count was quantified through common industry tests. Surface sponge swabs were also used to monitor tanker sanitation and the efficacy of cleaning treatments. Results did not identify a negative effect on raw milk quality due to extended duration hauling. Whereas the addition of RS did not provide any measurable quality benefits for the microbial milk quality, swab results demonstrated that the RS treatment was able to reduce surface bacteria in the tanker, although not to the same level as the full CIP treatment. Based on this study, current CIP practices for long distance milk hauling appear to be effective in mitigating any measurable effect on raw milk quality. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Habitual Sleep Duration and All-Cause Mortality in a General Community Sample.

PubMed

Aurora, R Nisha; Kim, Ji Soo; Crainiceanu, Ciprian; O'Hearn, Daniel; Punjabi, Naresh M

2016-11-01

The current study sought to determine whether sleep duration and change in sleep duration are associated with all-cause mortality in a community sample of middle-aged and older adults while accounting for several confounding factors including prevalent sleep-disordered breathing (SDB). Habitual sleep duration was assessed using self-report (< 7, 7-8, ≥ 9 h/night) at the baseline and at the follow-up visits of the Sleep Heart Health Study. Techniques of survival analysis were used to relate habitual sleep duration and change in sleep duration to all-cause mortality after adjusting for covariates such as age, sex, race, body mass index, smoking history, prevalent hypertension, diabetes, cardiovascular disease, antidepressant medication use, and SDB severity. Compared to a sleep duration of 7-8 h/night, habitually long sleep duration (≥ 9 h/night), but not short sleep duration (< 7 h/night), was associated with all-cause mortality with an adjusted hazards ratio of 1.25 (95% confidence interval [CI]: 1.05, 1.47). Participants who progressed from short or normal sleep duration to long sleep duration had increased risk for all-cause mortality with adjusted hazard ratios of 1.75 (95% CI: 1.08, 2.78) and 1.63 (95% CI: 1.26, 2.13), respectively. Finally, a change from long to short sleep duration was also associated with all-cause mortality. Long sleep duration or a shift from long to short sleep duration are independently associated with all-cause mortality. © 2016 Associated Professional Sleep Societies, LLC.

Effects of radiation quality, intensity, and duration on photosynthesis and growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bugbee, B.

1994-12-31

Differences in radiation quality from the six most common electric lamps have little effect on photosynthetic rate. Radiation quality primarily alters growth because of changes in branching or internode elongation, which change radiation absorption. Growth and yield in wheat appear to be insensitive to radiation quality. Growth and yield in soybeans can be slightly increased under high pressure sodium lamps compared to metal halide lamps, in spite of greatly reduced chlorophyll concentrations under HPS lamps. Daily integrated photosynthetic photon flux (mol m{sup -2} d{sup -1}) most directly determines leaf anatomy and growth. Photosynthetic photon flux levels of 800 {mu}mol m{supmore » -2} s{sup -1} are adequate to simulate field daily-integrated PPF levels for both short and long day plants, but plant canopies can benefit from much higher PPF levels.« less

Effects of radiation quality, intensity, and duration on photosynthesis and growth

NASA Technical Reports Server (NTRS)

Bugbee, Bruce

1994-01-01

Differences in radiation quality from the six most common electric lamps have little effect on photosynthetic rate. Radiation quality primarily alters growth because of changes in branching or internode elongation, which change radiation absorption. Growth and yield in wheat appear to be insensitive to radiation quality. Growth and yield in soybeans can be slightly increased under high pressure sodium (HPS) lamps compared to metal halide lamps, in spite of greatly reduced chlorophyll concentrations under HPS lamps. Daily integrated photosynthetic photon flux (mol m(exp -2)d(exp -1)) most directly determines leaf anatomy and growth. Photosynthetic photon flux (PPF) levels of 800 (mu)mol m(exp -2)s(exp -1) are adequate to simulate field daily-integrated PPF levels for both short and long day plants, but plant canopies can benefit from much higher PPF levels.

Key-peck durations under behavioral contrast and differential reinforcement

PubMed Central

Whipple, William R.; Fantino, Edmund

1980-01-01

Pigeons were maintained on a multiple schedule in which both components were variable-interval one-minute schedules. When they were switched to a condition in which one component was extinction, behavioral contrast was observed. The median durations of the key pecks in the unchanged component did not decrease in size. The results are incompatible with a theory of behavioral contrast which considers the added pecks to be short-duration responses. In a second experiment, pigeons were required to emit short-duration key pecks in one component of a multiple schedule, and long-duration pecks in the other. Two of three pigeons learned to emit responses appropriate to the requirements of the component in effect, suggesting that the duration of the key-peck response is sensitive to differential reinforcement. PMID:16812185

Analysis of the performance of the space ultravacuum research facility in attached and free-flyer mode

NASA Technical Reports Server (NTRS)

Naumann, Robert J.

1988-01-01

The old concept of using the wake of a spacecraft to obtain an ultrahigh vacuum is revisited with a somewhat different emphasis. Since it is possible to configure a wake shield so that a surface of interest does not subtend any walls that could become contaminated, it appears that it should be possible to achieve a contamination-free, ultrahigh vacuum capability with infinite pumping speed even in the presence of high heat loads and moderate gas loads. With the new interest in developing thin films with precision controlled synthetic microstructures such as superlattices, mixed metal oxide high temperature superconductors, rare-earth magneto-optical devices, and nano-crystalline alloys, the ability to work with a variety of different materials without cross contamination should be of significance. This paper analyzes the performance of the conceptual design for a Space Ultravacuum Research Facility (SURF), both in a Shuttle-attached mode and as a free-flyer. It is shown that even in the Shuttle-attached mode, it should be possible to obtain vacuum levels equivalent to 10 to the -10 Torr with O and N2 as the primary constituents. This should be sufficient to demonstrate the feasibility of the concept, particularly the infinite pumping speed and virtual elimination of contamination aspects. As a free-flyer the SURF will be limited primarily by the gas load associated with the process being performed. For chemical beam epitaxy (CBE) it is shown that equivalent vacuum levels of 10 to the -14 Torr should be possible at 300 km.

Thermotolerance and responses to short duration heat stress in tropical and temperate species

NASA Astrophysics Data System (ADS)

Marias, D.; Meinzer, F. C.; Still, C. J.

2017-12-01

phenotypically plastic and representative of the environment in which plants were grown, whereas iWUE appeared to reflect ecotypic differentiation and the climate of origin. Considering leaf age, heat stress duration, methodology, functional type, and climate of origin improves our understanding of physiological responses to short term heat stress.

Mars Flyer Rocket Propulsion Risk Assessment Kaiser Marquardt Testing

NASA Technical Reports Server (NTRS)

Marquardt, Kaiser

2001-01-01

This report describes the investigation of a 10-N, bipropellant thruster, operating at -40 C, with monomethylhydrazine (MMH) and 25% nitric oxide in nitrogen tetroxide (MON-25). The thruster testing was conducted as part of a risk reduction activity for the Mars Flyer, a proposed mission to fly a miniature airplane in the Martian atmosphere. Testing was conducted using an existing thruster, designed for MMH and MON-3 propellants. The nitric oxide content of MON-3 was increased to 25%, to lower its freezing point to -55 C. The thruster was conditioned, along with the propellants, to temperature prior to hot firing. Thruster operating parameters included oxidizer-to-fuel mixture ratios of 1.6 to 2.7 and inlet pressure ranging from 689 to 2070 kPa. The test matrix consisted of many 10-second firings and several 60-, 300-, 600-, and 1200-second firings, as well as pulse testing. The thruster successfully accumulated nearly 10,000 seconds of operation without failure, at temperatures ranging from -40 C to 22 C. At nominal inlet pressures, the ignition delay was comparable to MMH/MON-3 operation. The optimal performance for the 8.9-N thruster was determined to be at a mixture ratio of 1.93 with an average specific impulse of 298 sec.

Aerodynamic force measurement on a large-scale model in a short duration test facility

NASA Astrophysics Data System (ADS)

Tanno, H.; Kodera, M.; Komuro, T.; Sato, K.; Takahasi, M.; Itoh, K.

2005-03-01

A force measurement technique has been developed for large-scale aerodynamic models with a short test time. The technique is based on direct acceleration measurements, with miniature accelerometers mounted on a test model suspended by wires. Measuring acceleration at two different locations, the technique can eliminate oscillations from natural vibration of the model. The technique was used for drag force measurements on a 3m long supersonic combustor model in the HIEST free-piston driven shock tunnel. A time resolution of 350μs is guaranteed during measurements, whose resolution is enough for ms order test time in HIEST. To evaluate measurement reliability and accuracy, measured values were compared with results from a three-dimensional Navier-Stokes numerical simulation. The difference between measured values and numerical simulation values was less than 5%. We conclude that this measurement technique is sufficiently reliable for measuring aerodynamic force within test durations of 1ms.

Reduced sleep duration affects body composition, dietary intake and quality of life in obese subjects.

PubMed

Poggiogalle, Eleonora; Lubrano, Carla; Gnessi, Lucio; Marocco, Chiara; Di Lazzaro, Luca; Polidoro, Giampaolo; Luisi, Federica; Merola, Gianluca; Mariani, Stefania; Migliaccio, Silvia; Lenzi, Andrea; Donini, Lorenzo M

2016-09-01

Sleep duration has emerged as a crucial factor affecting body weight and feeding behaviour. The aim of our study was to explore the relationship among sleep duration, body composition, dietary intake, and quality of life (QoL) in obese subjects. Body composition was assessed by DXA. "Sensewear Armband" was used to evaluate sleep duration. SF-36 questionnaire was used to evaluate quality of life (QoL). A 3-day dietary record was administered. Subjects were divided into 2 groups: sleep duration > and ≤300 min/day. 137 subjects (105 women and 32 men), age: 49.8 ± 12.4 years, BMI: 38.6 ± 6.7 kg/m(2), were enrolled. Sleep duration was ≤300 min in 30.6 % of subjects. Absolute and relative fat mass (FM) (40.5 ± 9 vs. 36.5 ± 9.1 kg; 40.2 ± 4.7 vs. 36.9 ± 5.6 %), and truncal fat mass (19.2 ± 6.1 vs. 16.6 ± 5 kg; 38.6 ± 5.3 vs. 35.2 ± 5.5 %) were higher in subjects sleeping ≤300 min when compared to their counterparts (all p < 0.05), whereas just a tendency towards a higher BMI was observed (p = 0.077). Even though energy intake was not different between groups, subjects sleeping ≤300 min reported a higher carbohydrate consumption per day (51.8 ± 5.1 vs. 48.4 ± 9.2 %, p = 0.038). SF-36 total score was lower in subjects sleeping ≤300 min (34.2 ± 17.8 vs. 41.4 ± 12.9, p = 0.025). Sleep duration was negatively associated with FM (r = -0.25, p = 0.01) and SF-36 total score (r = -0.31, p < 0.001). The inverse association between sleep duration and SF-36 total score was confirmed by the regression analysis after adjustment for BMI and fat mass (R = 0.43, R (2) = 0.19, p = 0.012). Reduced sleep duration negatively influences body composition, macronutrient intake, and QoL in obese subjects.

Sociodemographic and socioeconomic differences in sleep duration and insomnia-related symptoms in Finnish adults

PubMed Central

2012-01-01

Background Poor sleep tends to be patterned by sociodemographic and socioeconomic factors. The aim of this study was to examine the associations of sociodemographic and socioeconomic factors with sleep duration and insomnia-related symptoms across life course. Methods We used cross-sectional Health 2000 Survey (2000–2001) among a total of 5,578 adult Finns, aged 30–79 years, representative of adult Finnish population. Data about sociodemographic and socioeconomic circumstances, insomnia-related symptoms over the previous month as well as average sleep duration were collected by questionnaires. Multinomial logistic regression models were adjusted first for gender and age, second for sociodemographic factors, third additionally for socioeconomic factors, and fourth for all covariates and self-perceived health simultaneously. Results On average 70% of Finnish adults slept 7–8 hours a day. Frequent insomnia-related symptoms were more prevalent among women (14%) than men (10%). Not being married, not having children, having low education, low income, being unemployed, and being a disability retiree were associated with frequent insomnia-related symptoms. Similar factors were associated with short and long sleep duration. However, childhood socioeconomic position was mostly unrelated to sleep in adulthood except parental education had some associations with short sleep duration. Conclusions Disadvantaged socioeconomic position in adulthood, in particular income and employment status, is associated with poorer sleep. When promoting optimal sleep duration and better sleep quality, families with low incomes, unemployed people, and disability retirees should be targeted. PMID:22839359

Effects of short-term high temperature on grain quality and starch granules of rice (Oryza sativa L.) at post-anthesis stage.

PubMed

Chen, Jianlin; Tang, Liang; Shi, Peihua; Yang, Baohua; Sun, Ting; Cao, Weixing; Zhu, Yan

2017-03-01

High temperature causes negative effects on grain yield and quality of rice (Oryza sativa L.). In this study, the effects of short-term high temperature (SHT) on grain quality and starch granules were investigated in two rice cultivars Nanjing 41 (NJ41, heat-sensitive) and Wuxiangjing 14 (WJ14, heat-tolerant) at post-anthesis stage (anthesis and early grain-filling stage). The results of rice quality analysis showed that chalky rate and chalkiness increased while brown rice rate, milled rice rate, and head rice rate decreased in two rice cultivars with the increase of high temperature and prolonged duration. Moreover, SHT stress reduced the accumulation of amylose as well as starch accumulation. The starch accumulation and eating quality were more sensitive to SHT than the appearance and milling quality. The starch structure data observed by scanning electron microscope further showed that the starch granules are arranged loosely and more single starch granules appeared after SHT treatment. The extent of change in rice quality and starch traits of WJ14 under SHT was lower than that of NJ41. The effects of SHT at anthesis stage were greater than that at grain-filling stage. Taken together, the results could help further understand the physiological and biochemical processes governing rice quality under high-temperature conditions.

Changes in Sleep Duration, Quality, and Medication Use Are Prospectively Associated With Health and Well-being: Analysis of the UK Household Longitudinal Study.

PubMed

Tang, Nicole K Y; Fiecas, Mark; Afolalu, Esther F; Wolke, Dieter

2017-03-01

Sleep is a plausible target for public health promotion. We examined the association of changes in sleep with subsequent health and well-being in the general population. We analyzed data from the UK Household Longitudinal Survey, involving 30594 people (aged > 16) who provided data on sleep and health and well-being at both Wave 1 (2009-2011) and Wave 4 (2012-2014) assessments. Predicting variables were changes in sleep quantity, sleep quality, and sleep medication use over the 4-year period. Outcome variables were the General Health Questionnaire (GHQ-12) and the 12-Item Short-Form Health Survey (SF-12) mental (MCS) and physical (PCS) component scores at Wave 4. Linear regression on each outcome was fully adjusted for potential confounders and baseline values of the relevant predicting and outcome variables. Better outcomes were associated with an increase in sleep duration (GHQ: β = 1.031 [95% confidence interval {CI}: -1.328, -0.734]; MCS: 1.531 [1.006, 2.055]; PCS: -0.071 [-0.419, 0.56]), sleep quality (GHQ: β = -2.031 [95% CI: -2.218, -1.844]; MCS: 3.027 [2.692, 3.361]; PCS: 0.924 [0.604, 1.245]), and a reduction in sleep medication use (GHQ: β = -1.929 [95% CI: -2.400, -1.459]; MCS: 3.106 [2.279, 3.933]; PCS: 2.633 [1.860, 3.406]). Poorer outcomes were on the other hand associated with a reduction in sleep duration, a decrease in sleep quality, and an increase in sleep medication use. Changes in sleep quality yielded the largest effects on the health and well-being outcomes. Changes in sleep were temporally associated with subsequent health and well-being. Initiatives that aim to protect a critical amount of sleep, promote sleep quality, and reduce sleep medication use may have public health values. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Short Sleep Duration is Associated with Obesity in Hispanic Manufacturing Workers.

PubMed

Benham, Grant; Ghaddar, Suad F; Talavera-Garza, Liza

2017-01-01

The present study examined the relationship between obesity and sleep duration among Hispanic manufacturing workers. Two hundred and twenty eight Hispanic workers from eight manufacturing plants completed an in-person interview that included measures of demographics, health literacy, and sleep duration. Height and weight were directly assessed. A logistic regression, controlling for gender, education, age, income, physical activity levels, self-reported health status, and health literacy, indicated that workers who slept six hours or less were significantly more likely to be obese than those sleeping seven to nine hours (OR: 1.90, 95% CI: 1.04-3.47). Our results extend previous research on the association between sleep duration and obesity to an understudied population of Hispanic workers.

Are sleep duration and sleep quality associated with diet quality, physical activity, and body weight status? A population-based study of Canadian children.

PubMed

Khan, Mohammad K A; Chu, Yen Li; Kirk, Sara F L; Veugelers, Paul J

2015-04-30

To describe sleep duration and sleep characteristics, and to examine the associations between sleep duration and characteristics and body weight status, diet quality, and physical activity levels among grade 5 children in Nova Scotia. A provincially representative sample of 5,560 grade 5 children and their parents in Nova Scotia was surveyed. Parents were asked to report their child's bedtime and wake-up time, and to indicate how often their child snored or felt sleepy during the day. Dietary intake and physical activity were selfreported by children using the Harvard Youth/Adolescent Food Frequency Questionnaire and the Physical Activity Questionnaire for Children respectively. Body weight status was determined using measured heights and weights. Linear and logistic random effects models with children nested within schools were used to test for associations. Approximately half of the surveyed parents reported that their children were not getting adequate sleep at night. Longer sleep duration was statistically significantly associated with decreased risk for overweight and obesity independent of other sleep characteristics (OR = 0.82, 95% CI: 0.73, 0.91). Longer sleep duration was also associated with better diet quality and higher levels of physical activity. These findings indicate a need for health promotion strategies to encourage adequate sleep and to promote healthy sleep environments among children. Given the links among sleep, body weight status and lifestyle behaviours, these messages should be included in public health interventions aimed at preventing obesity and promoting health among children.

Mechanisms of impaired exercise capacity in short duration experimental hyperthyroidism.

PubMed Central

Martin, W H; Spina, R J; Korte, E; Yarasheski, K E; Angelopoulos, T J; Nemeth, P M; Saffitz, J E

1991-01-01

To investigate the mechanism of reduced exercise tolerance in hyperthyroidism, we characterized cardiovascular function and determinants of skeletal muscle metabolism in 18 healthy subjects aged 26 +/- 1 yr (mean +/- SE) before and after 2 wk of daily ingestion of 100 micrograms of triiodothyronine (T3). Resting oxygen uptake, heart rate, and cardiac output increased and heart rate and cardiac output at the same submaximal exercise intensity were higher in the hyperthyroid state (P less than 0.05). However, maximal oxygen uptake decreased after T3 administration (3.08 +/- 0.17 vs. 2.94 +/- 0.19 l/min; P less than 0.001) despite increased heart rate and cardiac output at maximal exercise (P less than 0.05). Plasma lactic acid concentration at an equivalent submaximal exercise intensity was elevated 25% (P less than 0.01) and the arteriovenous oxygen difference at maximal effort was reduced (P less than 0.05) in the hyperthyroid state. These effects were associated with a 21-37% decline in activities of oxidative (P less than 0.001) and glycolytic (P less than 0.05) enzymes in skeletal muscle and a 15% decrease in type IIA muscle fiber cross-sectional area (P less than 0.05). Lean body mass was reduced (P less than 0.001) and the rates of whole body leucine oxidation and protein breakdown were enhanced (P less than 0.05). Thus, exercise tolerance is impaired in short duration hyperthyroidism because of decreased skeletal muscle mass and oxidative capacity related to accelerated protein catabolism but cardiac pump function is not reduced. PMID:1752962

Habitual Sleep Duration and All-Cause Mortality in a General Community Sample

PubMed Central

Aurora, R. Nisha; Kim, Ji Soo; Crainiceanu, Ciprian; O'Hearn, Daniel; Punjabi, Naresh M.

2016-01-01

Study Objectives: The current study sought to determine whether sleep duration and change in sleep duration are associated with all-cause mortality in a community sample of middle-aged and older adults while accounting for several confounding factors including prevalent sleep-disordered breathing (SDB). Methods: Habitual sleep duration was assessed using self-report (< 7, 7–8, ≥ 9 h/night) at the baseline and at the follow-up visits of the Sleep Heart Health Study. Techniques of survival analysis were used to relate habitual sleep duration and change in sleep duration to all-cause mortality after adjusting for covariates such as age, sex, race, body mass index, smoking history, prevalent hypertension, diabetes, cardiovascular disease, antidepressant medication use, and SDB severity. Results: Compared to a sleep duration of 7–8 h/night, habitually long sleep duration (≥ 9 h/night), but not short sleep duration (< 7 h/night), was associated with all-cause mortality with an adjusted hazards ratio of 1.25 (95% confidence interval [CI]: 1.05, 1.47). Participants who progressed from short or normal sleep duration to long sleep duration had increased risk for all-cause mortality with adjusted hazard ratios of 1.75 (95% CI: 1.08, 2.78) and 1.63 (95% CI: 1.26, 2.13), respectively. Finally, a change from long to short sleep duration was also associated with all-cause mortality. Conclusion: Long sleep duration or a shift from long to short sleep duration are independently associated with all-cause mortality. Citation: Aurora RN, Kim JS, Crainiceanu C, O'Hearn D, Punjabi NM. Habitual sleep duration and all-cause mortality in a general community sample. SLEEP 2016;39(11):1903–1909. PMID:27450684

Prediction of Quality of life by Self-Efficacy, Pain Intensity and Pain Duration in Patient with Pain Disorders

PubMed Central

Yazdi-Ravandi, Saeid; Taslimi, Zahra; Jamshidian, Narges; Saberi, Hayede; Shams, Jamal; Haghparast, Abbas

2013-01-01

The quality of life (QOL) has been defined as “a person's sense of well-being that stems from satisfaction or dissatisfaction with the areas of life that are important to him/her”. It is generally accepted that pain intensity and duration have a negative impact on the QOL. One specific type of control is “self-efficacy”, or the belief that one has the ability to successfully engage in specific actions. The ability to adapt to pain may play an important role in maintaining the QOL. In this study, we investigated the role of self-efficacy, pain intensity, and pain duration in various domains of quality of life such as physical, psychological, social and environmental domains. In this study, 290 adult patients (146 men, 144 women) completed coping self-efficacy and the WHOQOL-BREF Questionnaire. Moreover, we illustrated numerical rating scale for pain intensity. The results were analyzed using SPSS version of 19.0 and means, descriptive correlation, and regression were calculated. Our data revealed that self-efficacy but not the pain duration could significantly anticipate the QOL and its four related domains (P<0.001). In addition, it is noticeable that the effect of self-efficacy on the prediction of QOL is much more obvious in the psychological domain. However, the pain intensity could predict all of the QOL domains (P<0.001) except social and environmental ones. In conclusion, to predict the quality of life (QOL) in person suffering from chronic pain, self-efficacy and pain intensity are more important factors than the pain duration and demographic variables. PMID:25337337

Development of a Short Questionnaire to Assess Diet Quality among Older Community-Dwelling Adults.

PubMed

Robinson, S M; Jameson, K A; Bloom, I; Ntani, G; Crozier, S R; Syddall, H; Dennison, E M; Cooper, C R; Sayer, A A

2017-01-01

To evaluate the use of a short questionnaire to assess diet quality in older adults. Cross-sectional study. Hertfordshire, UK. 3217 community-dwelling older adults (59-73 years). Diet was assessed using an administered food frequency questionnaire (FFQ); two measures of diet quality were defined by calculating participants' 'prudent diet' scores, firstly from a principal component analysis of the data from the full FFQ (129 items) and, secondly, from a short version of the FFQ (including 24 indicator foods). Scores calculated from the full and short FFQ were compared with nutrient intake and blood concentrations of vitamin C and lipids. Prudent diet scores calculated from the full FFQ and short FFQ were highly correlated (0.912 in men, 0.904 in women). The pattern of associations between nutrient intake (full FFQ) and diet scores calculated using the short and full FFQs were very similar, both for men and women. Prudent diet scores calculated from the full and short FFQs also showed comparable patterns of association with blood measurements: in men and women, both scores were positively associated with plasma vitamin C concentration and serum HDL; in women, an inverse association with serum triglycerides was also observed. A short food-based questionnaire provides useful information about the diet quality of older adults. This simple tool does not require nutrient analysis, and has the potential to be of value to non-specialist researchers.

Early experience with laparoscopic extralevator abdominoperineal excision within an enhanced recovery setting: analysis of short-term outcomes and quality of life

PubMed Central

Vaughan-Shaw, PG; King, AT; Cheung, T; Beck, NE; Knight, JS; Nichols, PH; Nugent, KP; Pilkington, SA; Smallwood, JA; Mirnezami, AH

2011-01-01

INTRODUCTION Conventional abdominoperineal excision for low rectal cancer has a higher local recurrence and reduced survival compared to anterior resection. An extralevator abdominoperineal excision (ELAPE) may improve outcome through removal of increased tissue in the distal rectum. Experience with ELAPE is limited and no studies have reported on quality of life (QOL) following this procedure. We describe a minimally invasive approach to ELAPE within an enhanced recovery programme, and present short-term results and QOL analyses. METHODS All laparoscopic ELAPEs were included in a prospective database. Demographics, intra-operative and post-operative outcomes were evaluated. Postoperative QOL was assessed using the European Organisation for Research and Treatment of Cancer (EORTC) questionnaires QLQ-C30 and QLQ-CR29. RESULTS Thirteen laparoscopic ELAPEs were performed over a two-year period. All were enrolled in an enhanced recovery programme. The median age was 76. The median tumour height was 20mm (range: 0–50mm) from the dentate line and all patients received neoadjuvant treatment. The median duration of surgery was 300 minutes (range: 120–488 minutes), the mean blood loss was 150ml and one procedure was converted to open surgery. There was no circumferential resection margin involvement or tumour perforation. The median duration of use of intravenous fluid, patient controlled analgesia and urinary catheterisation was 2, 2 and 2.5 days respectively and the median length of hospital stay was 7.5 days. Two patients developed perineal wound dehiscence. QOL analysis revealed high global health status (90.8), physical (91.3), emotional (98.3) and social functioning (100) scores, which compared favourably with EORTC reference values and published QOL scores following conventional abdominoperineal excision. CONCLUSIONS Laparoscopic ELAPE within an enhanced recovery setting is a feasible and safe approach with acceptable short-term outcomes and post

Shorter sleep duration is associated with reduced cognitive development at two years of age.

PubMed

Smithson, Lisa; Baird, Tieghan; Tamana, Sukhpreet K; Lau, Amanda; Mariasine, Jennifer; Chikuma, Joyce; Lefebvre, Diana L; Subbarao, Padmaja; Becker, Allan B; Turvey, Stuart E; Sears, Malcolm R; Beal, Deryk S; Pei, Jacqueline; Mandhane, Piush J

2018-04-30

Both short sleep duration and sleep-disordered breathing (SDB) are associated with poor neurocognitive development. However, the co-contributions of short sleep duration and SDB on neurodevelopment in pre-school children are relatively unknown. We assessed both sleep duration and SDB by quarterly questionnaire from three months to two years of age among Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort participants. Group-based modeling determined trajectories of total, daytime, and nighttime sleep duration and SDB. Linear regression was used to assess the impact of sleep duration and SDB trajectories on cognitive (primary outcome) and language (secondary) development at two years of age as assessed by the Bayley Scale of Infant Development (BSID-III) (mean 100; standard deviation of 15). Of the 822 CHILD Edmonton participants, 703 (86%) were still enrolled at two years of age with 593 having BSID-III data at two years of age. Trajectory analysis identified four total sleep durations phenotypes [short sleepers (17.9%), decline to short sleepers (21.1%), intermediate sleepers (36.9%) and long sleepers (24.1%)]. Compared to children with intermediate sleep durations, short sleepers had a 5.2-point lower cognitive development score at two years of age [standard error (SE) 1.7; p = 0.002]. Nocturnal sleep duration, compared to daytime sleep duration had the greatest effect on cognitive development. We also identified three SDB symptom trajectories [early-onset SDB (15.7%), late-onset SDB (14.2%), and persistent SDB (5.3%)] and 79.5% of children had no SDB symptoms. Children with persistent SDB also had a 5.3-point lower language score (SE 2.7; p = 0.05) compared to children with no SDB. SDB trajectories were not associated with cognitive development. In a population-representative birth cohort study, both short sleep duration and SDB were associated with adverse neurodevelopment at two years of age. Children with short nighttime sleep

The relationship of lightning activity and short-duration rainfall events during warm seasons over the Beijing metropolitan region

NASA Astrophysics Data System (ADS)

Wu, Fan; Cui, Xiaopeng; Zhang, Da-Lin; Qiao, Lin

2017-10-01

The relationship between lightning activity and rainfall associated with 2925 short-duration rainfall (SDR) events over the Beijing metropolitan region (BMR) is examined during the warm seasons of 2006-2007, using the cloud-to-ground (CG) and intracloud (IC) lightning data from Surveillance et Alerte Foudre par Interférometrie Radioélectrique (SAFIR)-3000 and 5-min rainfall data from automatic weather stations (AWSs). An optimal radius of 10 km around selected AWSs is used to determine the lightning-rainfall relationship. The lightning-rainfall correlations vary significantly, depending upon the intensity of SDR events. That is, correlation coefficient (R 0.7) for the short-duration heavy rainfall (SDHR, i.e., ≥ 20 mm h- 1) events is found higher than that (R 0.4) for the weak SDR (i.e., 5-10 mm h- 1) events, and lower percentage of the SDHR events (< 10%) than the weak SDR events (40-50%) are observed with few flashes. Significant time-lagged correlations between lightning and rainfall are also found. About 80% of the SDR events could reach their highest correlation coefficients when the associated lightning flashes shift at time lags of < 25 min before and after rainfall begins. Those events with lightning preceding rainfall account for 50-60% of the total SDR events. Better lightning-rainfall correlations can be attained when time lags are incorporated, with the use of total (CG and IC) lightning data. These results appear to have important implications for improving the nowcast of SDHR events.

Effects of short-duration electromagnetic radiation on early postnatal neurogenesis in rats: Fos and NADPH-d histochemical studies.

PubMed

Orendáčová, Judita; Orendáč, Martin; Mojžiš, Miroslav; Labun, Ján; Martončíková, Marcela; Saganová, Kamila; Lievajová, Kamila; Blaško, Juraj; Abdiová, Henrieta; Gálik, Ján; Račeková, Eniko

2011-11-01

The immediate effects of whole body electromagnetic radiation (EMR) were used to study postnatal neurogenesis in the subventricular zone (SVZ) and rostral migratory stream (RMS) of Wistar rats of both sexes. Newborn postnatal day 7 (P7) and young adult rats (P28) were exposed to pulsed electromagnetic fields (EMF) at a frequency of 2.45 GHz and mean power density of 2.8 mW/cm(2) for 2 h. Post-irradiation changes were studied using immunohistochemical localization of Fos and NADPH-d. We found that short-duration exposure induces increased Fos immunoreactivity selectively in cells of the SVZ of P7 and P28 rats. There were no Fos positive cells visible within the RMS of irradiated rats. These findings indicate that some differences exist in prerequisites of proliferating cells between the SVZ and RMS regardless of the age of the rats. Short-duration exposure also caused praecox maturation of NADPH-d positive cells within the RMS of P7 rats. The NADPH-d positive cells appeared several days earlier than in age-matched controls, and their number and morphology showed characteristics of adult rats. On the other hand, in the young adult P28 rats, EMR induced morphological signs typical of early postnatal age. These findings indicate that EMR causes age-related changes in the production of nitric oxide (NO), which may lead to different courses of the proliferation cascade in newborn and young adult neurogenesis. Copyright © 2010 Elsevier GmbH. All rights reserved.

Intification and modelling of flight characteristics for self-build shock flyer type UAV

NASA Astrophysics Data System (ADS)

Rashid., Z. A.; Dardin, A. S. F. Syed.; Azid, A. A.; Ahmad, K. A.

2018-02-01

The development of an autonomous Unmanned Aerial Vehicle (UAV) requires a fundamentals studies of the UAV's flight characteristic. The aim of this study is to identify and model the flight characteristic of a conventional fixed-wing type UAV. Subsequence to this, the mode of flight of the UAV can be investigated. One technique to identify the characteristic of a UAV is a flight test where it required specific maneuvering to be executed while measuring the attitude sensor. In this study, a simple shock flyer type UAV was used as the aircraft. The result shows that the modeled flight characteristic has a significant relation with actual values but the fitting value is rather small. It is suggested that the future study is conducted with an improvement of the physical UAV, data filtering and better system identification methods.

Daily impaired detachment and short-term effects of impaired sleep quality on next-day commuting near-accidents - an ambulatory diary study.

PubMed

Pereira, Diana; Bucher, Sarah; Elfering, Achim

2016-08-01

This study investigated the short-term effects of daily recovery, that is, impaired psychological detachment from work and various actigraphical indicators of sleep quality, on near-accidents when commuting to work the next morning. Furthermore, the mediating effect of actigraphically assessed sleep quality on the relationship between impaired psychological detachment from work and near-accidents when commuting to work was analysed. Fifty-six full-time employees of a Swiss assurance company participated in the one-week study. Multilevel analyses revealed that impaired detachment was highly related to a decrease in sleep duration. Furthermore, impaired daily recovery processes, such as impaired psychological detachment from work and disturbed sleep quality, were related to commuting near-accidents. Impaired sleep quality mediated the effect of impaired psychological detachment from work on these near-accidents. Our results show that occupational safety interventions should address both impaired psychological detachment from work and sleep quality in order to prevent near accidents when commuting to work. Practitioner Summary: Commuting accidents occur frequently and have detrimental effects on employees, organisations and society. This study shows that daily lack of recovery, that is, impaired psychological detachment and impaired sleep quality, is related to near-accidents when commuting to work the next morning. Primary prevention of commuting accidents should therefore address daily lack of recovery.

The Nervous Flyer: Nerves, Flying and the First World War1

PubMed Central

Shaw Cobden, Lynsey

2018-01-01

This is not an article about ‘shell-shock’. It explores the military medical response to nervous disorders in the Royal Flying Corps. The First World War exposed the propensity of pilots to the nervous and psychological rigours of aerial warfare, but their unique experiences have been overlooked in favour of ‘trauma’ in infantrymen. This represents a critical lacuna in the historiography of military medicine, for flying personnel were studied apart from ‘shell-shocked’ soldiers. This article will show that flyers were believed to be medically different, and what set them apart from men in the trenches was their unique employment. The war necessitated, and provided the conditions for, the study of the medical problems of flying, including the significant nervous strains. Medical officers quickly established that flying not only affected bodily functions, but also ‘wore down’ the nerves that regulated psychological responses. This article will therefore present the medical view. It will study the research of air-minded medical officers and the conclusions reached on the nervous disorders of flying personnel. PMID:29528049

Exploration of Habitability Factors Influencing Short Duration Spaceflight: Structured Postflight Interviews of Shuttle Crewmembers

NASA Technical Reports Server (NTRS)

Locke, James; Leveton, Lauren; Keeton, Kathryn; Whitmire, Alexandra

2009-01-01

Astronauts report significant difficulties with sleep during Space missions. Psychological, physiological, and habitability factors are all thought to play a role in spaceflight insomnia. Crewmembers gain experience with the spaceflight sleep environment as their missions progress, but this knowledge is not formally collected and communicated to subsequent crews. This lack of information transfer prevents crews from optimizing their capability to sleep during mission, which leads to fatigue and its potentially deleterious effects. The goal of this project is astronauts with recent spaceflight experience to gather their knowledge of and insights into sleep in Space. Structured interviews consisting of standardized closed and open-ended questionnaires are administered to astronauts who have flown on the Space Shuttle since the Columbia disaster. It is hoped that review and analysis of the pooled responses to the interview questions will lead to greater understanding of the sleep environment during short duration spaceflight, with attention placed on problem aspects and their potential solutions.

Longitudinal associations between sleep duration and subsequent weight gain: A systematic review

PubMed Central

Magee, Lorrie

2011-01-01

Objective To systematically examine the relationship between sleep duration and subsequent weight gain in observational longitudinal human studies Methods Systematic review of twenty longitudinal studies published from 2004-October 31, 2010 Results While adult studies (n=13) reported inconsistent results on the relationship between sleep duration and subsequent weight gain, studies with children (n=7) more consistently reported a positive relationship between short sleep duration and weight gain. Conclusion While shorter sleep duration consistently predicts subsequent weight gain in children, the relationship is not clear in adults. We discuss possible limitations of the current studies: 1.) the diminishing association between short sleep duration on weight gain over time after transition to short sleep, 2.) lack of inclusion of appropriate confounding, mediating, and moderating variables (i.e. sleep complaints and sedentary behavior), and 3.) measurement issues. PMID:21784678

[Sleep duration and functional limitations in older adult].

PubMed

Eumann Mesas, Arthur; López-García, Esther; Rodríguez-Artalejo, Fernando

2011-04-30

To examine the association between sleep duration and functional limitation in older adults from Spain. Cross-sectional study with 3,708 individuals representative of the non-institutionalized population aged ≥ 60 years in Spain. Sleep duration was self-reported, and the functional limitations in the instrumental activities of daily living (IADL) were assessed. Functional limitations in IADL were identified in 1,424 (38.4%) participants. In analyses adjusted for sociodemographic and lifestyle variables, the percentage of participants with limitation in IADL was higher in those who slept ≤ 5 hours (odds ratio [OR]=1.56; 95% confidence interval [CI]=1.18-2.06) or ≥ 10 hours (OR=2.08; 95%CI=1.67-2.60; p for trend<0.001) than in those who slept 8 hours. The association between long sleep (≥ 10 hours) and functional limitations held even after adjustment for comorbidity and sleep quality (OR=1.77; 95%CI=1.38-2.28) while the association between short sleep (≤ 5 hours) and functional limitation no longer held after this adjustment (OR=1.10; 95%CI=0.80-1.50). In older adults, long sleep duration is a marker of functional limitations independent of comorbidity. Copyright © 2010 Elsevier España, S.L. All rights reserved.

Effects of different duration isometric contractions on tendon elasticity in human quadriceps muscles

PubMed Central

Kubo, Keitaro; Kanehisa, Hiroaki; Fukunaga, Tetsuo

2001-01-01

The present study aimed to investigate the influence of isometric training protocols with long- and short-duration contractions on the elasticity of human tendon structures in vivo. The elasticity was assessed through in vivo determination of the elongation (L) of the tendons and aponeuroses using ultrasonography, while the subjects performed ramp isometric exercise up to maximum voluntary contraction (MVC).Eight young males completed 12 weeks (4 days per week) of a unilateral isometric training programme on knee extensors, which consisted of two different combinations of contraction and relaxation times at 70 % MVC: one leg was trained using a short-duration protocol (3 sets of 50 repetitions of contraction for 1 s and relaxation for 2 s), and the other leg was trained using a long-duration protocol (4 sets of a combination of contraction for 20 s and relaxation for 1 min). The training volume per session, expressed as the integrated torque, was the same for the two protocols.Both protocols resulted in a significant increase in MVC: 31.8 ± 17.2 % for the short-duration protocol and 33.9 ± 14.4 % for the long-duration protocol. Moreover, the training produced significant increases in the muscle volume of the constituents of the quadriceps femoris, with similar relative gains for the two protocols: 7.4 ± 3.9 % for the short-duration protocol and 7.6 ± 4.3 % for the long-duration protocol.The short-duration protocol produced no significant change in L values at any of the force production levels. For the long-duration protocol, however, the L values above 550 N were significantly shorter after training. Analysis revealed that the group × test time interaction effect on tendon stiffness was significant. Stiffness increased significantly for the long-duration protocol, but not for the short-duration protocol.The present study demonstrates a greater increase in stiffness of human tendon structures following isometric training using longer duration contractions

[Sleep, work, and study: sleep duration in working and non-working students].

PubMed

Pereira, Erico Felden; Bernardo, Maria Perpeto Socorro Leite; D'Almeida, Vânia; Louzada, Fernando Mazzilli

2011-05-01

The aim of this study was to investigate the duration of sleep and associated factors in working and non-working students. Data were analyzed on the sleep-wake cycle in 863 teenage students in São Paulo, Brazil. Adjusted analyses were performed to compare sleep duration in working and non-working students. 18.4% of the group worked, and 52% of the working students slept eight hours or less per night. Prevalence of short sleep duration was higher in working students of both sexes (males, p = 0.017; females, p < 0.001). Working students showed short sleep duration in the analysis adjusted for socioeconomic status, but short sleep was more frequent in older adolescents (p = 0.004) and in lower (p = 0.001) and middle (p = 0.011) socioeconomic classes. Although more working students were in night school, in the model adjusted for gender and socioeconomic status, working students in afternoon courses showed higher prevalence of short sleep duration (PR = 2.53; 95%CI: 1.68-4.12).

Search for Transient Gravitational Waves in Coincidence with Short-Duration Radio Transients During 2007-2013

NASA Technical Reports Server (NTRS)

Abbott, B. P.; Hughey, Brennan; Zanolin, Michele; Szczepanczyk, Marek; Gill, Kiranjyot; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.;

Effects of attention bias modification with short and long stimulus-duration: A randomized experiment with individuals with subclinical social anxiety.

PubMed

Liang, Chi-Wen; Hsu, Wen-Yau

2016-06-30

This study investigated the differential effects of two attention bias modification (ABM) with different stimulus durations. Seventy-two undergraduates with subclinical social anxiety were randomly assigned to one of four conditions: an ABM condition with either a 100-ms or a 500-ms stimulus duration (ABM-100/ ABM-500) or an attention placebo (AP) condition with either a 100-ms or a 500-ms stimulus duration (AP-100/ AP-500). Participants completed the pre-assessments, eight attentional training sessions, and post-assessments. A modified Posner paradigm was used to assess changes in attentional processing. After completion of attentional training, the ABM-100 group significantly speeded up their responses to 100-ms invalid trials, regardless of the word type. The ABM-100 group also exhibited significant reduced latencies to 500-ms invalid social threat trials and a marginally significant reduced latencies to 500-ms invalid neutral trials. The ABM-500 group showed significant reduced latencies to 500-ms invalid social threat trials. Both ABMs significantly reduced participants' fear of negative evaluations and interactional anxiousness relative to their comparative AP. The effects on social anxiety did not differ between the two ABMs. This study suggests that although both ABMs using short and long stimulus durations reduce some aspects of social anxiety, they influence participants' attentional disengagement in different ways. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Objective Cognitive Functioning in Self-reported Habitual Short Sleepers not Reporting Daytime Dysfunction: Examination of Impulsivity via Delay Discounting.

PubMed

Curtis, Brian J; Williams, Paula G; Anderson, Jeffrey S

2018-05-30

1) Examine performance on an objective measure of reward-related cognitive impulsivity (delay discounting) among self-reported habitual short sleepers and medium (i.e., recommended 7-9 hours) length sleepers either reporting or not reporting daytime dysfunction; 2) Inform the debate regarding what type and duration of short sleep (e.g., 21 to 24 hours of total sleep deprivation, self-reported habitual short sleep duration) meaningfully influences cognitive impulsivity; 3) Compare the predictive utility of sleep duration and perceived dysfunction to other factors previously shown to influence cognitive impulsivity via delay discounting performance (age, income, education, and fluid intelligence). We analyzed data from 1,190 adults from the Human Connectome Project database. Participants were grouped on whether they reported habitual short (≤ 6 hours) vs. medium length (7-9 hours) sleep duration and whether they perceived daytime dysfunction using the Pittsburgh Sleep Quality Index. All short sleepers exhibited increased delay discounting compared to all medium length sleepers, regardless of perceived dysfunction. Of the variables examined, self-reported sleep duration was the strongest predictor of delay discounting behavior between groups and across all 1,190 participants. Individuals who report habitual short sleep are likely to exhibit increased reward-related cognitive impulsivity regardless of perceived sleep-related daytime impairment. Therefore, there is reason to suspect that these individuals exhibit more daytime dysfunction, in the form of reward-related cognitive impulsivity, than they may assume. Current findings suggest that assessment of sleep duration over the prior month has meaningful predictive utility for human reward-related impulsivity.

GRB 060505: A Possible Short-Duration Gamma-Ray Burst in a Star Forming Region at Redshift of 0.09

NASA Technical Reports Server (NTRS)

Ofek, E. O.; Cenko, S. B.; Gal-Yam, A.; Fox, D. B.; Nakar, E.; Rau, A.; Frail, D. A.; Kullkarni, S. R.; Price, P. A.; Schmidt, B. P.;

A mathematical model of diffusion from a steady source of short duration in a finite mixing layer

NASA Astrophysics Data System (ADS)

Bianconi, Roberto; Tamponi, Matteo

This paper presents an analytical unsteady-state solution to the atmospheric dispersion equation for substances subject to chemical-physical decay in a finite mixing layer for releases of short duration. This solution is suitable for describing critical events relative to accidental release of toxic, flammable or explosive substances. To implement the solution, the Modello per Rilasci a Breve Termine (MRBT) code has been developed, for some characteristics parameters of which the results of the sensitivity analysis are presented. Moreover some examples of application to the calculation of exposure to toxic substances and to the determination of the ignition field of flammable substances are described. Finally, the mathematical model described can be used to interpret the phenomenon of pollutant accumulation.

BOLD temporal dynamics of rat superior colliculus and lateral geniculate nucleus following short duration visual stimulation.

PubMed

Lau, Condon; Zhou, Iris Y; Cheung, Matthew M; Chan, Kevin C; Wu, Ed X

2011-04-29

The superior colliculus (SC) and lateral geniculate nucleus (LGN) are important subcortical structures for vision. Much of our understanding of vision was obtained using invasive and small field of view (FOV) techniques. In this study, we use non-invasive, large FOV blood oxygenation level-dependent (BOLD) fMRI to measure the SC and LGN's response temporal dynamics following short duration (1 s) visual stimulation. Experiments are performed at 7 tesla on Sprague Dawley rats stimulated in one eye with flashing light. Gradient-echo and spin-echo sequences are used to provide complementary information. An anatomical image is acquired from one rat after injection of monocrystalline iron oxide nanoparticles (MION), a blood vessel contrast agent. BOLD responses are concentrated in the contralateral SC and LGN. The SC BOLD signal measured with gradient-echo rises to 50% of maximum amplitude (PEAK) 0.2±0.2 s before the LGN signal (p<0.05). The LGN signal returns to 50% of PEAK 1.4±1.2 s before the SC signal (p<0.05). These results indicate the SC signal rises faster than the LGN signal but settles slower. Spin-echo results support these findings. The post-MION image shows the SC and LGN lie beneath large blood vessels. This subcortical vasculature is similar to that in the cortex, which also lies beneath large vessels. The LGN lies closer to the large vessels than much of the SC. The differences in response timing between SC and LGN are very similar to those between deep and shallow cortical layers following electrical stimulation, which are related to depth-dependent blood vessel dilation rates. This combined with the similarities in vasculature between subcortex and cortex suggest the SC and LGN timing differences are also related to depth-dependent dilation rates. This study shows for the first time that BOLD responses in the rat SC and LGN following short duration visual stimulation are temporally different.

Self-reported sleep duration and daytime napping are associated with renal hyperfiltration in general population.

PubMed

Lin, Miao; Su, Qing; Wen, Junping; Wei, Shichao; Yao, Jin; Huang, Huibin; Liang, Jixing; Li, Liantao; Lin, Wei; Lin, Lixiang; Lu, Jieli; Bi, Yufang; Wang, Weiqing; Ning, Guang; Chen, Gang

2018-03-01

Renal hyperfiltration (RHF) has emerged as a novel marker of early renal damage in various conditions such as diabetes and metabolic syndrome. Aberrant sleep duration and excessive daytime napping may affect the development of chronic kidney disease (CKD). In this study, the association between sleep duration, daytime napping, and renal hyperfiltration was assessed. This study was conducted in three communities in China. A total of 16,119 community volunteers (5735 males and 10,384 females) aged 40-65 years without CKD were included for the study. Participants with short sleep duration (<6 h/day) or long sleep duration (≥10 h/day) were at a significantly increased risk of renal hyperfiltration. The fully adjusted ORs (95% CI) were 2.112 (1.107, 4.031) and 2.071 (1.504, 2.853), respectively (P < 0.05). In addition, those who took naps longer than 1.5 h per day had a higher risk of renal hyperfiltration compared with those without napping (OR 1.400, 95% CI 1.018-1.924). Further joint analysis indicated that participants with long sleep duration (≥10 h/day) had a more than twofold increased risk of RHF regardless of nap status compared with those who slept 8-9 h per day without daytime napping. The association between sleep duration or daytime napping and RHF could not be explained by the influence of sleep quality. Additional subgroup analysis showed long sleep duration (≥9 h/day) and long daytime napping (≥1.5 h) were associated with an increased risk of RHF among individuals with good sleep quality. Sleep duration less than 6 h/day or more than 10 h/day and long daytime napping tend to be associated with an increased risk of renal hyperfiltration in middle-aged general population, and this relationship was independent of diabetes, hypertension, obesity, or poor sleep quality.

Effects of short read quality and quantity on a de novo vertebrate transcriptome assembly.

PubMed

Garcia, T I; Shen, Y; Catchen, J; Amores, A; Schartl, M; Postlethwait, J; Walter, R B

2012-01-01

For many researchers, next generation sequencing data holds the key to answering a category of questions previously unassailable. One of the important and challenging steps in achieving these goals is accurately assembling the massive quantity of short sequencing reads into full nucleic acid sequences. For research groups working with non-model or wild systems, short read assembly can pose a significant challenge due to the lack of pre-existing EST or genome reference libraries. While many publications describe the overall process of sequencing and assembly, few address the topic of how many and what types of reads are best for assembly. The goal of this project was use real world data to explore the effects of read quantity and short read quality scores on the resulting de novo assemblies. Using several samples of short reads of various sizes and qualities we produced many assemblies in an automated manner. We observe how the properties of read length, read quality, and read quantity affect the resulting assemblies and provide some general recommendations based on our real-world data set. Published by Elsevier Inc.

Use of social media is associated with short sleep duration in a dose-response manner in students aged 11 to 20 years.

PubMed

Sampasa-Kanyinga, Hugues; Hamilton, Hayley A; Chaput, Jean-Philippe

2018-04-01

This study examined the association between social media and sleep duration among Canadian students aged 11-20. Data from 5242 students were obtained from the 2015 Ontario Student Drug Use and Health Survey, a province-wide, school-based survey that has been conducted every two years since 1977. We measured the respondents' sleep duration against the recommended ranges of 9-11 h per night at 11-13 years of age, 8-10 h at 14-17 and 7-9 h per night for those aged 18 years or more. Overall, 36.4% of students met or exceeded the recommended sleep duration and 63.6% slept less than recommended, with 73.4% of students reporting that they used social media for at least one hour per day. After adjusting for various covariates, the use of social media was associated with greater odds of short sleep duration in a dose-response manner (p for linear trend <0.001). Odds ratios ranged from 1.82 for social media use of at least one hour per day to 2.98 for at least five hours per day. Greater use of social media was associated with shorter sleep duration in a dose-response fashion among Canadian students aged 11-20. ©2018 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.