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Sample records for investigating motion sickness

  1. Hyperventilation in a motion sickness desensitization program

    NARCIS (Netherlands)

    Mert, A.; Bles, W.; Nooij, S.A.E.

    2007-01-01

    Introduction: In motion sickness desensitization programs, the motion sickness provocative stimulus is often a forward bending of the trunk on a rotating chair, inducing Coriolis effects. Since respiratory relaxation techniques are applied successfully in these courses, we investigated whether these

  2. [Pharmacological prophylaxis of vestibulo-autonomous syndrome (motion sickness) in model investigations].

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    Shashkov, V S; Iasnetsov, V V; Shashkov, A V; Il'ina, S L; Galle, R R; Sabaev, V V; Potapov, M G

    2000-01-01

    The authors summarize results of multiyear investigations at the Institute of Biomedical Problems of induced motion sickness and development of prophylactic medicaments representing various classes of biologically active substances (choline blocking agents, sympathomimetics, antihistamines etc.) prescribed singularly or in an combination based on the knowledge of MS-provoking inter-receptor interactions and therapeutic effects of drugs.

  3. Travelers' Health: Motion Sickness

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    ... sickness, especially when pregnant, menstruating, or on hormones. Race/ethnicity—Asians may be more susceptible to motion ... it, sitting in the front seat of a car or bus, sitting over the wing of an ...

  4. Dizziness and Motion Sickness

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    ... that extends into the inner ear can completely destroy both the hearing and equilibrium function of that ... motion sickness: •Do not read while traveling •Avoid sitting in the rear seat •Do not sit in ...

  5. Motion Sickness: First Aid

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    ... com. Accessed July 29, 2017. Priesol AJ. Motion sickness. https://www.uptodate.com/content/search. Accessed July 29, 2017. Brunette GW, et al. CDC Health Information for International Travel 2018. New York, N. ...

  6. A re-investigation of the role of utricular asymmetries in Space Motion Sickness

    NARCIS (Netherlands)

    Nooij, S.A.E.; Vanspauwen, R.; Bos, J.E.; Wuyts, F.L.

    2011-01-01

    During the first days of spaceflight, about 50-70% of the astronauts experience symptoms of Space Motion Sickness (SMS). It has been proposed that an asymmetry between the left and right otolith organs contributes to an astronaut's individual susceptibility. A recently developed test to measure

  7. General Automatic Components of Motion Sickness

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    Suter, S.; Toscano, W. B.; Kamiya, J.; Naifeh, K.

    1985-01-01

    A body of investigations performed in support of experiments aboard the space shuttle, and designed to counteract the symptoms of Space Adaptation Syndrome, which resemble those of motion sickness on Earth is reviewed. For these supporting studies, the automatic manifestations of earth-based motion sickness was examined. Heart rate, respiration rate, finger pulse volume and basal skin resistance were measured on 127 men and women before, during and after exposure to nauseogenic rotating chair tests. Significant changes in all autonomic responses were observed across the tests. Significant differences in autonomic responses among groups divided according to motion sickness susceptibility were also observed. Results suggest that the examination of autonomic responses as an objective indicator of motion sickness malaise is warranted and may contribute to the overall understanding of the syndrome on Earth and in Space.

  8. Artificial horizon effects on motion sickness and performance.

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    Tal, Dror; Gonen, Adi; Wiener, Guy; Bar, Ronen; Gil, Amnon; Nachum, Zohar; Shupak, Avi

    2012-07-01

    To investigate whether the projection of Earth-referenced scenes during provocative motion can alleviate motion sickness severity and prevent motion sickness-induced degradation of performance. Exposure to unfamiliar motion patterns commonly results in motion sickness and decreased performance. Thirty subjects with moderate-to-severe motion sickness susceptibility were exposed to the recorded motion profile of a missile boat under moderate sea conditions in a 3-degrees-of-freedom ship motion simulator. During a 120-minute simulated voyage, the study participants were repeatedly put through a performance test battery and completed a motion sickness susceptibility questionnaire, while self-referenced and Earth-referenced visual scenes were projected inside the closed simulator cabin. A significant decrease was found in the maximal motion sickness severity score, from 9.83 ± 9.77 (mean ± standard deviation) to 7.23 ± 7.14 (p pitch, and heave movements of the simulator. Although there was a significant decrease in sickness severity, substantial symptoms still persisted. Decision making, vision, concentration, memory, simple reasoning, and psychomotor skills all deteriorated under the motion conditions. However, no significant differences between the projection conditions could be found in the scores of any of the performance tests. Visual information regarding the vessel's movement provided by an artificial horizon device might decrease motion sickness symptoms. However, although this device might be suitable for passive transportation, the continued deterioration in performance measures indicates that it provides no significant advantage for personnel engaged in the active operation of modern vessels.

  9. Motion sickness: a negative reinforcement model.

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    Bowins, Brad

    2010-01-15

    Theories pertaining to the "why" of motion sickness are in short supply relative to those detailing the "how." Considering the profoundly disturbing and dysfunctional symptoms of motion sickness, it is difficult to conceive of why this condition is so strongly biologically based in humans and most other mammalian and primate species. It is posited that motion sickness evolved as a potent negative reinforcement system designed to terminate motion involving sensory conflict or postural instability. During our evolution and that of many other species, motion of this type would have impaired evolutionary fitness via injury and/or signaling weakness and vulnerability to predators. The symptoms of motion sickness strongly motivate the individual to terminate the offending motion by early avoidance, cessation of movement, or removal of oneself from the source. The motion sickness negative reinforcement mechanism functions much like pain to strongly motivate evolutionary fitness preserving behavior. Alternative why theories focusing on the elimination of neurotoxins and the discouragement of motion programs yielding vestibular conflict suffer from several problems, foremost that neither can account for the rarity of motion sickness in infants and toddlers. The negative reinforcement model proposed here readily accounts for the absence of motion sickness in infants and toddlers, in that providing strong motivation to terminate aberrant motion does not make sense until a child is old enough to act on this motivation.

  10. Motion sickness in ancient China: Seasickness and cart-sickness.

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    Brandt, Thomas; Bauer, Matthias; Benson, Judy; Huppert, Doreen

    2016-07-19

    To find and analyze descriptions of motion sickness in Chinese historical sources. Databases and dictionaries were searched for various terms for seasickness and travel sickness, which were then entered into databases of full texts allowing selection of relevant passages from about the third to the 19th century ad. Already in 300 ad the Chinese differentiated cart-sickness, particularly experienced by persons from the arid north of China, from a ship-illness experienced by persons from the south, where rivers were important for transportation and travel. In the Middle Ages, a third form of motion sickness was called litter-influence experienced by persons transported in a bed suspended between 2 long poles. The ancient Chinese recognized the particular susceptibility of children to motion sickness. Therapeutic recommendations include drinking the urine of young boys, swallowing white sand-syrup, collecting water drops from a bamboo stick, or hiding some earth from the middle of the kitchen hearth under the hair. The Chinese medical classics distinguished several forms of travel sickness, all of which had their own written characters. The pathophysiologic mechanism was explained by the medicine of correspondences, which was based on malfunctions within the body, its invasion by external pathogens like wind, or the deficit or surfeit of certain bodily substances such as the life force Qi. The concept of motion as the trigger of sickness initially appeared in a chapter on warding off the influence of demons and corpses, e.g., ancient magic and beliefs. © 2016 American Academy of Neurology.

  11. Motion sickness, stress and the endocannabinoid system.

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    Alexander Choukèr

    Full Text Available BACKGROUND: A substantial number of individuals are at risk for the development of motion sickness induced nausea and vomiting (N&V during road, air or sea travel. Motion sickness can be extremely stressful but the neurobiologic mechanisms leading to motion sickness are not clear. The endocannabinoid system (ECS represents an important neuromodulator of stress and N&V. Inhibitory effects of the ECS on N&V are mediated by endocannabinoid-receptor activation. METHODOLOGY/PRINCIPAL FINDINGS: We studied the activity of the ECS in human volunteers (n = 21 during parabolic flight maneuvers (PFs. During PFs, microgravity conditions (<10(-2 g are generated for approximately 22 s which results in a profound kinetic stimulus. Blood endocannabinoids (anandamide and 2-arachidonoylglycerol, 2-AG were measured from blood samples taken in-flight before start of the parabolic maneuvers, after 10, 20, and 30 parabolas, in-flight after termination of PFs and 24 h later. Volunteers who developed acute motion sickness (n = 7 showed significantly higher stress scores but lower endocannabinoid levels during PFs. After 20 parabolas, blood anandamide levels had dropped significantly in volunteers with motion sickness (from 0.39+/-0.40 to 0.22+/-0.25 ng/ml but increased in participants without the condition (from 0.43+/-0.23 to 0.60+/-0.38 ng/ml resulting in significantly higher anandamide levels in participants without motion sickness (p = 0.02. 2-AG levels in individuals with motion sickness were low and almost unchanged throughout the experiment but showed a robust increase in participants without motion sickness. Cannabinoid-receptor 1 (CB1 but not cannabinoid-receptor 2 (CB2 mRNA expression in leucocytes 4 h after the experiment was significantly lower in volunteers with motion sickness than in participants without N&V. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate that stress and motion sickness in humans are associated with impaired endocannabinoid

  12. Stroboscopic Goggles for Reduction of Motion Sickness

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    Reschke, M. F.; Somers, Jeffrey T.

    2005-01-01

    A device built around a pair of electronic shutters has been demonstrated to be effective as a prototype of stroboscopic goggles or eyeglasses for preventing or reducing motion sickness. The momentary opening of the shutters helps to suppress a phenomenon that is known in the art as retinal slip and is described more fully below. While a number of different environmental factors can induce motion sickness, a common factor associated with every known motion environment is sensory confusion or sensory mismatch. Motion sickness is a product of misinformation arriving at a central point in the nervous system from the senses from which one determines one s spatial orientation. When information from the eyes, ears, joints, and pressure receptors are all in agreement as to one s orientation, there is no motion sickness. When one or more sensory input(s) to the brain is not expected, or conflicts with what is anticipated, the end product is motion sickness. Normally, an observer s eye moves, compensating for the anticipated effect of motion, in such a manner that the image of an object moving relatively to an observer is held stationary on the retina. In almost every known environment that induces motion sickness, a change in the gain (in the signal-processing sense of gain ) of the vestibular system causes the motion of the eye to fail to hold images stationary on the retina, and the resulting motion of the images is termed retinal slip. The present concept of stroboscopic goggles or eyeglasses (see figure) is based on the proposition that prevention of retinal slip, and hence, the prevention of sensory mismatch, can be expected to reduce the tendency toward motion sickness. A device according to this concept helps to prevent retinal slip by providing snapshots of the visual environment through electronic shutters that are brief enough that each snapshot freezes the image on each retina. The exposure time for each snapshot is less than 5 ms. In the event that a higher

  13. Do lower vertebrates suffer from motion sickness?

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    Lychakov, Dmitri

    The poster presents literature data and results of the author’s studies with the goal to find out whether the lower animals are susceptible to motion sickness (Lychakov, 2012). In our studies, fish and amphibians were tested for 2 h and more by using a rotating device (f = 0.24 Hz, a _{centrifugal} = 0.144 g) and a parallel swing (f = 0.2 Hz, a _{horizontal} = 0.059 g). The performed studies did not revealed in 4 fish species and in toads any characteristic reactions of the motion sickness (sopite syndrome, prodromal preparatory behavior, vomiting). At the same time, in toads there appeared characteristic stress reactions (escape response, an increase of the number of urinations, inhibition of appetite), as well as some other reactions not associated with motion sickness (regular head movements, eye retractions). In trout fry the used stimulation promoted division of the individuals into the groups differing by locomotor reaction to stress, as well as the individuals with the well-expressed compensatory reaction that we called the otolithotropic reaction. Analysis of results obtained by other authors confirms our conclusions. Thus, the lower vertebrates, unlike mammals, are immune to motion sickness either under the land conditions or under conditions of weightlessness. On the basis of available experimental data and theoretical concepts of mechanisms of development the motion sickness, formulated in several hypotheses (mismatch hypothesis, Traisman‘ s hypothesis, resonance hypothesis), there presented the synthetic hypothesis of motion sickness that has the conceptual significance. According to the hypothesis, the unusual stimulation producing sensor-motor or sensor-sensor conflict or an action of vestibular and visual stimuli of frequency of about 0.2 Hz is perceived by CNS as poisoning and causes the corresponding reactions. The motion sickness actually is a byproduct of technical evolution. It is suggested that in the lower vertebrates, unlike mammals

  14. The effect of mild motion sickness and sopite syndrome on multitasking cognitive performance.

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    Matsangas, Panagiotis; McCauley, Michael E; Becker, William

    2014-09-01

    In this study, we investigated the effects of mild motion sickness and sopite syndrome on multitasking cognitive performance. Despite knowledge on general motion sickness, little is known about the effect of motion sickness and sopite syndrome on multitasking cognitive performance. Specifically, there is a gap in existing knowledge in the gray area of mild motion sickness. Fifty-one healthy individuals performed a multitasking battery. Three independent groups of participants were exposed to two experimental sessions. Two groups received motion only in the first or the second session, whereas the control group did not receive motion. Measurements of motion sickness, sopite syndrome, alertness, and performance were collected during the experiment Only during the second session, motion sickness and sopite syndrome had a significant negative association with cognitive performance. Significant performance differences between symptomatic and asymptomatic participants in the second session were identified in composite (9.43%), memory (31.7%), and arithmetic (14.7%) task scores. The results suggest that performance retention between sessions was not affected by mild motion sickness. Multitasking cognitive performance declined even when motion sickness and soporific symptoms were mild. The results also show an order effect. We postulate that the differential effect of session on the association between symptomatology and multitasking performance may be related to the attentional resources allocated to performing the multiple tasks. Results suggest an inverse relationship between motion sickness effects on performance and the cognitive effort focused on performing a task. Even mild motion sickness has potential implications for multitasking operational performance.

  15. Respiratory impact on motion sickness induced by linear motion

    NARCIS (Netherlands)

    Mert, A.; Klöpping-Ketelaars, I.; Bles, W.

    2009-01-01

    Motion sickness incidence (MSI) for vertical sinusoidal motion reaches a maximum at 0.167 Hz. Normal breathing frequency is close to this frequency. There is some evidence for synchronization of breathing with this stimulus frequency. If this enforced breathing takes place over a larger frequency

  16. Genetics Home Reference: motion sickness

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    ... motion, particularly traveling in a car, bus, train, airplane, or boat. Amusement park rides, skiing, and virtual ... Association ClinicalTrials.gov (1 link) ClinicalTrials.gov Scientific Articles on PubMed (1 link) PubMed OMIM (1 link) ...

  17. Eye movements to yaw, pitch, and roll about vertical and horizontal axes : Adaptation and motion sickness

    NARCIS (Netherlands)

    Bos, J. E.; van der Bles, W.; de Graaf, B.

    2002-01-01

    Background: In the search for parameters to predict motion sickness that can be measured in the laboratory, we performed a longitudinal investigation in aviators. Since the vestibular system is involved in the generation of motion sickness as well as eye movements, vestibuloocular reflex (VOR)

  18. Eye movements to yaw, pitch, and roll about vertical and horizontal axes : Adaptation, and motion sickness

    NARCIS (Netherlands)

    Bos, J.E.; Bles, W.; Graaf, B. de

    2002-01-01

    Background: In the search for parameters to predict motion sickness that can be measured in the laboratory, we performed a longitudinal investigation in aviators. Since the vestibular system is involved in the generation of motion sickness as well as eye movements, vestibulo-ocular reflex (VOR)

  19. Motion sickness and postural sway in console video games.

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    Stoffregen, Thomas A; Faugloire, Elise; Yoshida, Ken; Flanagan, Moira B; Merhi, Omar

    2008-04-01

    We tested the hypotheses that (a) participants might develop motion sickness while playing "off-the-shelf" console video games and (b) postural motion would differ between sick and well participants, prior to the onset of motion sickness. There have been many anecdotal reports of motion sickness among people who play console video games (e.g., Xbox, PlayStation). Participants (40 undergraduate students) played a game continuously for up to 50 min while standing or sitting. We varied the distance to the display screen (and, consequently, the visual angle of the display). Across conditions, the incidence of motion sickness ranged from 42% to 56%; incidence did not differ across conditions. During game play, head and torso motion differed between sick and well participants prior to the onset of subjective symptoms of motion sickness. The results indicate that console video games carry a significant risk of motion sickness. Potential applications of this research include changes in the design of console video games and recommendations for how such systems should be used.

  20. [Vestibular testing abnormalities in individuals with motion sickness].

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    Ma, Yan; Ou, Yongkang; Chen, Ling; Zheng, Yiqing

    2009-08-01

    To evaluate the vestibular function of motion sickness. VNG, which tests the vestibular function of horizontal semicircular canal, and CPT, which tests vestibulospinal reflex and judge proprioceptive, visual and vestibular status, were performed in 30 motion sickness patients and 20 healthy volunteers (control group). Graybiel score was recorded at the same time. Two groups' Graybiel score (12.67 +/- 11.78 vs 2.10 +/- 6.23; rank test P<0.05), caloric test labyrinth value [(19.02 +/- 8.59) degrees/s vs (13.58 +/- 5.25) degrees/s; t test P<0.05], caloric test labyrinth value of three patients in motion sickness group exceeded 75 degrees/s. In computerized posturography testing (CPT), motion sickness patients were central type (66.7%) and disperse type (23.3%); all of control group were central type. There was statistical significance in two groups' CTP area, and motion sickness group was obviously higher than control group. While stimulating vestibulum in CPT, there was abnormality (35%-50%) in motion sickness group and none in control group. Generally evaluating CPT, there was only 2 proprioceptive hypofunction, 3 visual hypofunction, and no vestibular hypofunction, but none hypofunction in control group. Motion sickness patients have high vestibular susceptible, some with vestibular hyperfunction. In posturography, a large number of motion sickness patients are central type but no vestibular hypofunction, but it is hard to keep balance when stimulating vestibulum.

  1. Various anti-motion sickness drugs and core body temperature changes.

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    Cheung, Bob; Nakashima, Ann M; Hofer, Kevin D

    2011-04-01

    Blood flow changes and inactivity associated with motion sickness appear to exacerbate the rate of core temperature decrease during subsequent body cooling. We investigated the effects of various classes of anti-motion sickness drugs on core temperature changes. There were 12 healthy male and female subjects (20-35 yr old) who were given selected classes of anti-motion sickness drugs prior to vestibular Coriolis cross coupling induced by graded yaw rotation and periodic pitch-forward head movements in the sagittal plane. All subjects were then immersed in water at 18 degrees C for a maximum of 90 min or until their core temperature reached 35 degrees C. Double-blind randomized trials were administered, including a placebo, a non-immersion control with no drug, and six anti-motion sickness drugs: meclizine, dimenhydrinate, chlorpheniramine, promethazine + dexamphetamine, promethazine + caffeine, and scopolamine + dexamphetamine. A 7-d washout period was observed between trials. Core temperature and the severity of sickness were monitored throughout each trial. A repeated measures design was performed on the severity of sickness and core temperature changes prior to motion provocation, immediately after the motion sickness end point, and throughout the period of cold-water immersion. The most effective anti-motion sickness drugs, promethazine + dexamphetamine (with a sickness score/duration of 0.65 +/- 0.17) and scopolamine + dexamphetamine (with a sickness score/duration of 0.79 +/- 0.17), significantly attenuated the decrease in core temperature. The effect of this attenuation was lower in less effective drugs. Our results suggest that the two most effective anti-motion sickness drugs are also the most effective in attenuating the rate of core temperature decrease.

  2. Pharmacological and neurophysiological aspects of space/motion sickness

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    Lucot, James B.; Crampton, George H.

    1991-01-01

    A motorized motion testing device modeled after a Ferris wheel was constructed to perform motion sickness tests on cats. Details of the testing are presented, and some of the topics covered include the following: xylazine-induced emesis; analysis of the constituents of the cerebrospinal fluid (CSF) during motion sickness; evaluation of serotonin-1A (5-HT sub 1A) agonists; other 5HT receptors; antimuscarinic mechanisms; and antihistaminergic mechanisms. The ability of the following drugs to reduce motion sickness in the cats was examined: amphetamines, adenosinergic drugs, opioid antagonists, peptides, cannabinoids, cognitive enhancers (nootropics), dextromethorphan/sigma ligands, scopolamine, and diphenhydramine.

  3. Motion sickness history, food neophobia, and sensation seeking.

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    Alley, Thomas R; Willet, Kathleen A; Muth, Eric R

    2006-06-01

    Motion sickness is believed to be caused by conflicting sensory signals, a situation that mimics the effects of ingesting certain toxins. Thus, one might suspect that individuals who have experienced a relatively high frequency of motion sickness may be particularly vigilant about avoiding anything that produces nausea, induding potentially nauseating toxins. Consequently, they may be more resistant to trying new foods, i.e., be more food neophobic, since unfamiliar foods can have unexpected adverse effects due to toxins or allergens. Likewise, many highly stimulating experiences can trigger motion sickness, so individuals who are more susceptible may be more prone to avoid such experiences, i.e., be less sensation seeking. Finally, it was expected that food neophobia would be more frequent in individuals low on sensation seeking tendencies. Self-reported motion sickness history in 308 adults (M= 18.8 yr.; SD = 1.6) was correlated with scores on the Arnett Inventory of Sensation Seeking and the Food Neophobia Scale. As predicted, greater history of motion sickness was associated with lower Sensation Seeking scores. Food Neophobia was not correlated with motion sickness history but, as expected, was negatively correlated (r = -.42) with scores on Sensation Seeking. Further research is recommended that measures actual sensitivity to motion sickness.

  4. Virtual reality sickness questionnaire (VRSQ): Motion sickness measurement index in a virtual reality environment.

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    Kim, Hyun K; Park, Jaehyun; Choi, Yeongcheol; Choe, Mungyeong

    2018-05-01

    This study aims to develop a motion sickness measurement index in a virtual reality (VR) environment. The VR market is in an early stage of market formation and technological development, and thus, research on the side effects of VR devices such as simulator motion sickness is lacking. In this study, we used the simulator sickness questionnaire (SSQ), which has been traditionally used for simulator motion sickness measurement. To measure the motion sickness in a VR environment, 24 users performed target selection tasks using a VR device. The SSQ was administered immediately after each task, and the order of work was determined using the Latin square design. The existing SSQ was revised to develop a VR sickness questionnaire, which is used as the measurement index in a VR environment. In addition, the target selection method and button size were found to be significant factors that affect motion sickness in a VR environment. The results of this study are expected to be used for measuring and designing simulator sickness using VR devices in future studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Evaluation of the relationship between motion sickness symptomatology and blood pressure, heart rate, and body temperature

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    Graybiel, A.; Lackner, J. R.

    1980-01-01

    This study investigated the relationship between the development of symptoms of motion sickness and changes in blood pressure, heart rate, and body temperature. Twelve subjects were each evaluated four times using the vestibular-visual interaction test (Graybiel and Lackner, 1980). The results were analyzed both within and across individual subjects. Neither a systematic group nor consistent individual relationship was found between the physiological parameters and the appearance of symptoms of motion sickness. These findings suggest that biofeedback control of the physiological variables studied is not likely to prevent the expression of motion sickness symptomatology.

  6. A preliminary study of MR sickness evaluation using visual motion aftereffect for advanced driver assistance systems.

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    Nakajima, Sawako; Ino, Shuichi; Ifukube, Tohru

    2007-01-01

    Mixed Reality (MR) technologies have recently been explored in many areas of Human-Machine Interface (HMI) such as medicine, manufacturing, entertainment and education. However MR sickness, a kind of motion sickness is caused by sensory conflicts between the real world and virtual world. The purpose of this paper is to find out a new evaluation method of motion and MR sickness. This paper investigates a relationship between the whole-body vibration related to MR technologies and the motion aftereffect (MAE) phenomenon in the human visual system. This MR environment is modeled after advanced driver assistance systems in near-future vehicles. The seated subjects in the MR simulator were shaken in the pitch direction ranging from 0.1 to 2.0 Hz. Results show that MAE is useful for evaluation of MR sickness incidence. In addition, a method to reduce the MR sickness by auditory stimulation is proposed.

  7. Reliability of provocative tests of motion sickness susceptibility

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    Calkins, D. S.; Reschke, M. F.; Kennedy, R. S.; Dunlop, W. P.

    1987-01-01

    Test-retest reliability values were derived from motion sickness susceptibility scores obtained from two successive exposures to each of three tests: (1) Coriolis sickness sensitivity test; (2) staircase velocity movement test; and (3) parabolic flight static chair test. The reliability of the three tests ranged from 0.70 to 0.88. Normalizing values from predictors with skewed distributions improved the reliability.

  8. Effects of Autonomic Conditioning on Motion Sickness Tolerance

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    Cowings, P. S.; Toscano, W. B.

    1994-01-01

    This paper presents case-studies of 9 shuttle crewmembers (prime and alternates) and one U.S. Navy F-18 pilot, as they participated in all preflight training and testing activities in support of a life sciences flight experiment aboard Spacelab-J, and Spacelab-3. The primary objective of the flight experiment was to determine if Autogenic-feedback training (AFT), a physiological self-regulation training technique would be an effective treatment for motion sickness and space motion sickness in these crewmembers. Additional objectives of this study involved the examining human Physiological- responses to motion sickness on Earth and in space, as well as developing predictive criteria for susceptibility to space motion sickness based on ground-based data. Comparisons of these crewmembers are made to a larger set of subjects from previous experiments (treatment and test-only controls subjects). This paper describes all preflight methods, results and proposed changes for future tests.

  9. Reliability of Autonomic Responses and Malaise Across Multiple Motion Sickness Stimulation Tests

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    Stout, Cynthia S.; Toscano, William B.; Cowings, Patricia S.

    1993-01-01

    There is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation. Additionally, a paucity of data exists that examines the variability within an individual across repeated motion sickness tests. Investigators have also examined the relationship of autonomic responses to motion sickness development. These investigations have used analyses at discrete points in time to describe this relationship. This approach fails to address the time course of autonomic responses and malaise development throughout the motion sickness test. Our objectives were to examine the reliability of autonomic responses and malaise using the final minute of the motion sickness test across five testing occasions, to examine the reliability of the change in autonomic responses and the change in malaise across five testing occasions, and to examine the relationship between changes in autonomic responses and changes in malaise level across the entire motion sickness test. Our results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and malaise throughout the test duration were less stable across the tests. We attribute this instability to variations in individual susceptibility and the error associated with estimating a measure of autonomic gain.

  10. Vection and visually induced motion sickness: How are they related?

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    Behrang eKeshavarz

    2015-04-01

    Full Text Available The occurrence of visually induced motion sickness has been frequently linked to the sensation of illusory self-motion (so-called vection, however, the precise nature of this relationship is still not fully understood. To date, it is still a matter of debate whether or not vection is a necessary prerequisite for visually induced motion sickness (VIMS. That is, can there be visually induced motion sickness without any sensation of self-motion? In this paper, we will describe the possible nature of this relationship, review the literature that may speak to this relationship (including theoretical accounts of vection and VIMS, and offer suggestions with respect to operationally defining and reporting these phenomena in future.

  11. Effects of decades of physical driving on body movement and motion sickness during virtual driving.

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    Thomas A Stoffregen

    Full Text Available We investigated relations between experience driving physical automobiles and motion sickness during the driving of virtual automobiles. Middle-aged individuals drove a virtual automobile in a driving video game. Drivers were individuals who had possessed a driver's license for approximately 30 years, and who drove regularly, while non-drivers were individuals who had never held a driver's license, or who had not driven for more than 15 years. During virtual driving, we monitored movement of the head and torso. During virtual driving, drivers became motion sick more rapidly than non-drivers, but the incidence and severity of motion sickness did not differ as a function of driving experience. Patterns of movement during virtual driving differed as a function of driving experience. Separately, movement differed between participants who later became motion sick and those who did not. Most importantly, physical driving experience influenced patterns of postural activity that preceded motion sickness during virtual driving. The results are consistent with the postural instability theory of motion sickness, and help to illuminate relations between the control of physical and virtual vehicles.

  12. Potential non-pharmacological countermeasures for motion sickness

    NARCIS (Netherlands)

    Houben, M.M.J.; Bos, J.E.; Groen, E.L.

    2012-01-01

    Motion sickness can occur in any motion environment to which a person is not adapted, varying from cars, boats, and planes to fun rides and virtual reality. With symptoms such as nausea, vomiting, headache, lethargy, dizziness, and loss of concentration it causes discomfort for passengers but also a

  13. Sensory conflict in motion sickness: An observer theory approach

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    Oman, Charles M.

    1989-01-01

    Motion sickness is the general term describing a group of common nausea syndromes originally attributed to motion-induced cerebral ischemia, stimulation of abdominal organ afferent, or overstimulation of the vestibular organs of the inner ear. Sea-, car-, and airsicknesses are the most commonly experienced examples. However, the discovery of other variants such as Cinerama-, flight simulator-, spectacle-, and space sickness in which the physical motion of the head and body is normal or absent has led to a succession of sensory conflict theories which offer a more comprehensive etiologic perspective. Implicit in the conflict theory is the hypothesis that neutral and/or humoral signals originate in regions of the brain subversing spatial orientation, and that these signals somehow traverse to other centers mediating sickness symptoms. Unfortunately, the present understanding of the neurophysiological basis of motion sickness is far from complete. No sensory conflict neuron or process has yet been physiologically identified. To what extent can the existing theory be reconciled with current knowledge of the physiology and pharmacology of nausea and vomiting. The stimuli which causes sickness, synthesizes a contemporary Observer Theory view of the Sensory Conflict hypothesis are reviewed, and a revised model for the dynamic coupling between the putative conflict signals and nausea magnitude estimates is presented. The use of quantitative models for sensory conflict offers a possible new approach to improving the design of visual and motion systems for flight simulators and other virtual environment display systems.

  14. Motion in images is essential to cause motion sickness symptoms, but not to increase postural sway

    NARCIS (Netherlands)

    Lubeck, A.J.A.; Bos, J.E.; Stins, J.F.

    2015-01-01

    Abstract Objective It is generally assumed that motion in motion images is responsible for increased postural sway as well as for visually induced motion sickness (VIMS). However, this has not yet been tested. To that end, we studied postural sway and VIMS induced by motion and still images. Method

  15. Motion control, motion sickness, and the postural dynamics of mobile devices.

    Science.gov (United States)

    Stoffregen, Thomas A; Chen, Yi-Chou; Koslucher, Frank C

    2014-04-01

    Drivers are less likely than passengers to experience motion sickness, an effect that is important for any theoretical account of motion sickness etiology. We asked whether different types of control would affect the incidence of motion sickness, and whether any such effects would be related to participants' control of their own bodies. Participants played a video game on a tablet computer. In the Touch condition, the device was stationary and participants controlled the game exclusively through fingertip inputs via the device's touch screen. In the Tilt condition, participants held the device in their hands and moved the device to control some game functions. Results revealed that the incidence of motion sickness was greater in the Touch condition than in the Tilt condition. During game play, movement of the head and torso differed as a function of the type of game control. Before the onset of subjective symptoms of motion sickness, movement of the head and torso differed between participants who later reported motion sickness and those that did not. We discuss implications of these results for theories of motion sickness etiology.

  16. Motion sickness and tilts of the inertial force environment : Active suspension systems vs. active passengers

    NARCIS (Netherlands)

    Golding, J. F.; van der Bles, W.; Bos, J. E.; Haynes, T.; Gresty, M. A.

    2003-01-01

    Background: Maneuvering in vehicles exposes occupants to low frequency forces (<1 Hz) which can provoke motion sickness. Hypothesis: Aligning with the tilting inertial resultant (gravity + imposed horizontal acceleration: gravito-inertial force (GIF)) may reduce motion sickness when tilting is

  17. Reliability of psychophysiological responses across multiple motion sickness stimulation tests

    Science.gov (United States)

    Stout, C. S.; Toscano, W. B.; Cowings, P. S.

    1995-01-01

    Although there is general agreement that a high degree of variability exists between subjects in their autonomic nervous system responses to motion sickness stimulation, very little evidence exists that examines the reproducibility of autonomic responses within subjects during motion sickness stimulation. Our objectives were to examine the reliability of autonomic responses and symptom levels across five testing occasions using the (1) final minute of testing, (2) change in autonomic response and the change in symptom level, and (3) strength of the relationship between the change in symptom level and the change in autonomic responses across the entire motion sickness test. The results indicate that, based on the final minute of testing, the autonomic responses of heart rate, blood volume pulse, and respiration rate are moderately stable across multiple tests. Changes in heart rate, blood volume pulse, respiration rate, and symptoms throughout the test duration are less stable across the tests. Finally, autonomic responses and symptom levels are significantly related across the entire motion sickness test.

  18. Motion Cues in Flight Simulation and Simulator Induced Sickness

    Science.gov (United States)

    1988-06-01

    military F7 .. vehicles, surface excavation equipment, underground mining devices, railway locomotives, .A space vehicles, shiv bridges, and submarines. Of...Evaluatort Rleference to Fukuda is: Fukuda, T. Postural behavior and motion sickness. Acca Otolaryngol. (Stockholm), 1976, B1:37-241.) %kI RTD-5

  19. Motion sickness symptoms in a ship motion simulator: effects of inside, outside, and no view

    NARCIS (Netherlands)

    Bos, J.E.; MacKinnon, S.N.; Patterson, A.

    2005-01-01

    Vehicle motion characteristics differ between air, road, and sea environments, both vestibularly and visually. Effects of vision on motion sickness have been studied before, though less systematically in a naval setting. It is hypothesized that appropriate visual information on self-motion is

  20. Pleasant music as a countermeasure against visually induced motion sickness.

    Science.gov (United States)

    Keshavarz, Behrang; Hecht, Heiko

    2014-05-01

    Visually induced motion sickness (VIMS) is a well-known side-effect in virtual environments or simulators. However, effective behavioral countermeasures against VIMS are still sparse. In this study, we tested whether music can reduce the severity of VIMS. Ninety-three volunteers were immersed in an approximately 14-minute-long video taken during a bicycle ride. Participants were randomly assigned to one of four experimental groups, either including relaxing music, neutral music, stressful music, or no music. Sickness scores were collected using the Fast Motion Sickness Scale and the Simulator Sickness Questionnaire. Results showed an overall trend for relaxing music to reduce the severity of VIMS. When factoring in the subjective pleasantness of the music, a significant reduction of VIMS occurred only when the presented music was perceived as pleasant, regardless of the music type. In addition, we found a gender effect with women reporting more sickness than men. We assume that the presentation of pleasant music can be an effective, low-cost, and easy-to-administer method to reduce VIMS. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  1. Comparison of treatment strategies for Space Motion Sickness

    Science.gov (United States)

    Davis, J. R.; Jennings, R. T.; Beck, B. G.

    1992-01-01

    Treatment strategies for Space Motion Sickness were compared using the results of postflight oral debriefings. Standardized questionnaires were administered to all crewmembers immediately following Space Shuttle flights by NASA flight surgeons. Cases of Space Motion Sickness were graded as mild, moderate or severe based on published criteria, and medication effectiveness was judged based on subjective reports of symptom relief. Since October 1989, medication effectiveness is reported inflight through Private Medical Conferences with the crew. A symptom matrix was analyzed for 19 crewmembers treated with an oral combination of scopolamine and dextroamphetamine (scopdex) and 15 crewmembers treated with promethazine delivered by intramuscular (IM) or suppository routes. Scopdex has been given preflight as prophaxis for Space Motion Sickness but analysis showed delayed symptom presentation in 9 crewmembers or failed to prevent symptoms in 7. Only three crewmembers who took scopdex had no symptoms inflight. Fourteen out of 15 crewmembers treated with IM promethazine and 6 of 8 treated with promethazine suppositories after symptom development had immediate (within 12 h) symptom relief and required no additional medication. There were no cases of delayed symptom presentation in the crewmembers treated with promethazine. This response is in contrast to untreated crewmembers who typically have slow symptom resolution over 72-96 h. We conclude that promethazine is an effective treatment of Space Motion Sickness symptoms inflight. NASA policy currently recommends treating crewmembers with Space Motion Sickness after symptom development, and no longer recommends prophylaxis with scopdex due to delayed symptom development and apparent variable absorption of oral medications during early flight days.

  2. Autogenic feedback training experiment: A preventative method for space motion sickness

    Science.gov (United States)

    Cowings, Patricia S.

    1993-01-01

    Space motion sickness is a disorder which produces symptoms similar to those of motion sickness on Earth. This syndrome has affected approximately 50 percent of all astronauts and cosmonauts exposed to microgravity in space, but it differs from what is commonly known as motion sickness in a number of critical ways. There is currently no ground-based method for predicting susceptibility to motion sickness in space. Antimotion sickness drugs have had limited success in preventing or counteracting symptoms in space, and frequently caused debilitating side effects. The objectives were: (1) to evaluate the effectiveness of Autogenic-Feedback Training as a countermeasure for space motion sickness; (2) to compare physiological data and in-flight symptom reports to ground-based motion sickness data; and (3) to predict susceptibility to space motion sickness based on pre-flight data of each treatment group crew member.

  3. Space motion sickness: The sensory motor controls and cardiovascular correlation

    Science.gov (United States)

    Souvestre, Philippe A.; Blaber, Andrew P.; Landrock, Clinton K.

    impacts on core regulatory sensory motor and cognitive mechanisms. Static postural analysis provides specific central neurophysiological markers that can reliably identify PDS occurrence among classic peripheral musculoskeletal and spinal data [C. Landrock, P.A. Souvestre, Static postural analysis: a methodology to assess gravity related sensory motor controls' status for astronauts, 2006-01-2298, 36th SAE-ICES]. Many astronauts experience PFOI and recent research has implicated altered autonomic cardiovascular regulation caused by microgravity. HRV measurements have been used to determine if some pre-flight autonomic indicators relating to PFOI may exist by differentiating parasympathetic and sympathetic activity. ResultsThis review suggests a new approach to SMS mitigation based on specific neurophysiological assessment criteria. While SMS may not be a "unique diagnosis", it should be treated as result, or symptom of, the condition space adaptation syndrome (SAS), which can be shown to be a unique diagnosis. This methodology can identify and measure brain functional status in specific areas during pre-flight and post-flight examinations. This could provide further understanding on why, how and when SMS and PFOI might occur in Astronauts, and lead to criteria that predict susceptibility to SMS. An additional test component is presented that relates to using static central sensory-motor data towards understanding SMS and OI occurrence. Recent investigations indicate relationship between HRV autonomic indicators with Motion Sickness [B. Cheung, K. Hoffer, R. Heskin, A. Smith, Physiological and behavioral responses to an exposure to pitch illusion in the simulator, Aviation Space, 2004; Y. Yokota, M. Aoki, K. Mizuta, Y. Ito, N. Isu, Motion sickness susceptibility associated with visually induced postural instability and cardiac autonomic responses in healthy subjects, Acta Oto-laryngological, 2005]. It is found that astronauts with lower sympatho-vagal balance and higher

  4. Subjective Vertical Conflict Theory and Space Motion Sickness.

    Science.gov (United States)

    Chen, Wei; Chao, Jian-Gang; Wang, Jin-Kun; Chen, Xue-Wen; Tan, Cheng

    2016-02-01

    Space motion sickness (SMS) remains a troublesome problem during spaceflight. The subjective vertical (SV) conflict theory postulates that all motion sickness provoking situations are characterized by a condition in which the SV sensed from gravity and visual and idiotropic cues differs from the expected vertical. This theory has been successfully used to predict motion sickness in different vehicles on Earth. We have summarized the most outstanding and recent studies on the illusions and characteristics associated with spatial disorientation and SMS during weightlessness, such as cognitive map and mental rotation, the visual reorientation and inversion illusions, and orientation preferences between visual scenes and the internal z-axis of the body. The relationships between the SV and the incidence of and susceptibility to SMS as well as spatial disorientation were addressed. A consistent framework was presented to understand and explain SMS characteristics in more detail on the basis of the SV conflict theory, which is expected to be more advantageous in SMS prediction, prevention, and training.

  5. Mechanisms of selective attention and space motion sickness

    Science.gov (United States)

    Kohl, R. L.

    1987-01-01

    The neural mismatch theory of space motion sickness asserts that the central and peripheral autonomic sequelae of discordant sensory input arise from central integrative processes falling to reconcile patterns of incoming sensory information with existing memory. Stated differently, perceived novelty reaches a stress level as integrative mechanisms fail to return a sense of control to the individual in the new environment. Based on evidence summarized here, the severity of the neural mismatch may be dependent upon the relative amount of attention selectively afforded to each sensory input competing for control of behavior. Components of the limbic system may play important roles in match-mismatch operations, be therapeutically modulated by antimotion sickness drugs, and be optimally positioned to control autonomic output.

  6. Roll motion stimuli : sensory conflict, perceptual weighting and motion sickness

    NARCIS (Netherlands)

    Graaf, B. de; Bles, W.; Bos, J.E.

    1998-01-01

    In an experiment with seventeen subjects interactions of visual roll motion stimuli and vestibular body tilt stimuli were examined in determining the subjective vertical. Interindi-vidual differences in weighting the visual information were observed, but in general visual and vestibular responses

  7. Motion sickness incidence during a round-the-world yacht race.

    Science.gov (United States)

    Turner, M; Griffin, M J

    1995-09-01

    Motion sickness experiences were obtained from participants in a 9 month, round the world yacht race. Race participants completed questionnaires on their motion sickness experience 1 week prior to the start of the race, during the race, and following the race. Yacht headings, sea states, and wind directions were recorded throughout the race. Illness and the occurrence of vomiting were related to the duration at sea and yacht encounter directions relative to the prevailing wind. Individual crewmember characteristics, the use of anti-motion sickness drugs, activity while at sea, and after-effects of yacht motion were also examined with respect to sickness occurrence. Sickness was greatest among females and younger crewmembers, and among crewmembers who used anti-motion sickness drugs. Sickness varied as a function of drug type and activity while at sea. Crewmembers who reported after-effects of yacht motion also reported greater sickness while at sea. The primary determinants of motion sickness were the duration of time spent at sea and yacht encounter direction to the prevailing wind.

  8. Demonstrating the potential for dynamic auditory stimulation to contribute to motion sickness.

    Directory of Open Access Journals (Sweden)

    Behrang Keshavarz

    Full Text Available Auditory cues can create the illusion of self-motion (vection in the absence of visual or physical stimulation. The present study aimed to determine whether auditory cues alone can also elicit motion sickness and how auditory cues contribute to motion sickness when added to visual motion stimuli. Twenty participants were seated in front of a curved projection display and were exposed to a virtual scene that constantly rotated around the participant's vertical axis. The virtual scene contained either visual-only, auditory-only, or a combination of corresponding visual and auditory cues. All participants performed all three conditions in a counterbalanced order. Participants tilted their heads alternately towards the right or left shoulder in all conditions during stimulus exposure in order to create pseudo-Coriolis effects and to maximize the likelihood for motion sickness. Measurements of motion sickness (onset, severity, vection (latency, strength, duration, and postural steadiness (center of pressure were recorded. Results showed that adding auditory cues to the visual stimuli did not, on average, affect motion sickness and postural steadiness, but it did reduce vection onset times and increased vection strength compared to pure visual or pure auditory stimulation. Eighteen of the 20 participants reported at least slight motion sickness in the two conditions including visual stimuli. More interestingly, six participants also reported slight motion sickness during pure auditory stimulation and two of the six participants stopped the pure auditory test session due to motion sickness. The present study is the first to demonstrate that motion sickness may be caused by pure auditory stimulation, which we refer to as "auditorily induced motion sickness".

  9. Motion sickness and tilts of the inertial force environment: active suspension systems vs. active passengers

    NARCIS (Netherlands)

    Golding, J.F.; Bles, W.; Bos, J.E.; Haynes, T.; Gresty, M.A.

    2003-01-01

    Maneuvering in vehicles exposes occupants to low frequency forces (<1 Hz) which can provoke motion sickness. Hypothesis: Aligning with the tilting inertial resultant (gravity + imposed horizontal acceleration: gravito-inertial force (GIF)) may reduce motion sickness when tilting is either 'active'

  10. Autogenic-feedback training exercise is superior to promethazine for control of motion sickness symptoms

    Science.gov (United States)

    Cowings, P. S.; Toscano, W. B.

    2000-01-01

    Motion sickness symptoms affect approximately 50% of the crew during space travel and are commonly treated with intramuscular injections of promethazine. The purpose of this paper is to compare the effectiveness of three treatments for motion sickness: intramuscular injections (i.m.) of promethazine, a physiological training method (autogenic-feedback training exercise [AFTE]), and a no-treatment control. An earlier study tested the effects of promethazine on cognitive and psychomotor performance and motion sickness tolerance in a rotating chair. For the present paper, motion sickness tolerance, symptom reports, and physiological responses of these subjects were compared to matched subjects selected from an existing database who received either AFTE or no treatment. Three groups of 11 men, between the ages of 33 and 40 years, were matched on the number of rotations tolerated during their initial rotating-chair motion sickness test. The motion sickness test procedures and the 7-day interval between tests were the same for all subjects. The drug group was tested under four treatment conditions: baseline (no injections), a 25 mg dose of promethazine, a 50 mg dose of promethazine, and a placebo of sterile saline. AFTE subjects were given four 30-minute AFTE sessions before their second, third, and fourth motion sickness tests (6 hours total). The no-treatment control subjects were only given the four rotating-chair tests. Motion sickness tolerance was significantly increased after 4 hours of AFTE when compared to either 25 mg (p training.

  11. Motion sickness and otolith sensitivity - A pilot study of habituation to linear acceleration

    Science.gov (United States)

    Potvin, A. R.; Sadoff, M.; Billingham, J.

    1977-01-01

    Astronauts, particularly in Skylab flights, experienced varying degrees of motion sickness lasting 3-5 days. One possible mechanism for this motion sickness adaptation is believed to be a reduction in otolith sensitivity with an attendant reduction in sensory conflict. In an attempt to determine if this hypothesis is valid, a ground-based pilot study was conducted on a vertical linear accelerator. The extent of habituation to accelerations which initially produced motion sickness was evaluated, along with the possible value of habituation training to minimize the space motion sickness problem. Results showed that habituation occurred for 6 of the 8 subjects tested. However, in tests designed to measure dynamic and static otolith function, no significant differences between pre- and post-habituation tests were observed. Cross habituation effects to a standard Coriolis acceleration test were not significant. It is unlikely that ground-based pre-habituation to linear accelerations of the type examined would alter susceptibility to space motion sickness.

  12. Motion sickness increases the risk of accidental hypothermia.

    Science.gov (United States)

    Nobel, Gerard; Eiken, Ola; Tribukait, Arne; Kölegård, Roger; Mekjavic, Igor B

    2006-09-01

    Motion sickness (MS) has been found to increase body-core cooling during immersion in 28 degrees C water, an effect ascribed to attenuation of the cold-induced peripheral vasoconstriction (Mekjavic et al. in J Physiol 535(2):619-623, 2001). The present study tested the hypothesis that a more profound cold stimulus would override the MS effect on peripheral vasoconstriction and hence on the core cooling rate. Eleven healthy subjects underwent two separate head-out immersions in 15 degrees C water. In the control trial (CN), subjects were immersed after baseline measurements. In the MS-trial, subjects were rendered motion sick prior to immersion, by using a rotating chair in combination with a regimen of standardized head movements. During immersion in the MS-trial, subjects were exposed to an optokinetic stimulus (rotating drum). At 5-min intervals subjects rated their temperature perception, thermal comfort and MS discomfort. During immersion mean skin temperature, rectal temperature, the difference in temperature between the non-immersed right forearm and 3rd finger of the right hand (DeltaTff), oxygen uptake and heart rate were recorded. In the MS-trial, rectal temperature decreased substantially faster (33%, P < 0.01). Also, the DeltaTff response, an index of peripheral vasomotor tone, as well as the oxygen uptake, indicative of the shivering response, were significantly attenuated (P < 0.01 and P < 0.001, respectively) by MS. Thus, MS may predispose individuals to hypothermia by enhancing heat loss and attenuating heat production. This might have significant implications for survival in maritime accidents.

  13. Console video games, postural activity, and motion sickness during passive restraint.

    Science.gov (United States)

    Chang, Chih-Hui; Pan, Wu-Wen; Chen, Fu-Chen; Stoffregen, Thomas A

    2013-08-01

    We examined the influence of passive restraint on postural activity and motion sickness in individuals who actively controlled a potentially nauseogenic visual motion stimulus (a driving video game). Twenty-four adults (20.09 ± 1.56 years; 167.80 ± 7.94 cm; 59.02 ± 9.18 kg) were recruited as participants. Using elastic bands, standing participants were passively restrained at the head, shoulders, hips, and knees. During restraint, participants played (i.e., controlled) a driving video game (a motorcycle race), for 50 min. During game play, we recorded the movement of the head and torso, using a magnetic tracking system. Following game play, participants answered a forced choice, yes/no question about whether they were motion sick, and were assigned to sick and well groups on this basis. In addition, before and after game play, participants completed the Simulator Sickness Questionnaire, which provided numerical ratings of the severity of individual symptoms. Five of 24 participants (20.83 %) reported motion sickness. Participants moved despite being passively restrained. Both the magnitude and the temporal dynamics of movement differed between the sick and well groups. The results show that passive restraint of the body can reduce motion sickness when the nauseogenic visual stimulus is under participants' active control and confirm that motion sickness is preceded by distinct patterns of postural activity even during passive restraint.

  14. The efficacy of airflow and seat vibration on reducing visually induced motion sickness.

    Science.gov (United States)

    D'Amour, Sarah; Bos, Jelte E; Keshavarz, Behrang

    2017-09-01

    Visually induced motion sickness (VIMS) is a well-known sensation in virtual environments and simulators, typically characterized by a variety of symptoms such as pallor, sweating, dizziness, fatigue, and/or nausea. Numerous methods to reduce VIMS have been previously introduced; however, a reliable countermeasure is still missing. In the present study, the effect of airflow and seat vibration to alleviate VIMS was investigated. Eighty-two participants were randomly assigned to one of four groups (airflow, vibration, combined airflow and vibration, and control) and then exposed to a 15 min long video of a bicycle ride shot from first-person view. VIMS was measured using the Fast Motion Sickness Scale (FMS) and the Simulator Sickness Questionnaire (SSQ). Results showed that the exposure of airflow significantly reduced VIMS, whereas the presence of seat vibration, in contrast, did not have an impact on VIMS. Additionally, we found that females reported higher FMS scores than males, however, this sex difference was not found in the SSQ scores. Our findings demonstrate that airflow can be an effective and easy-to-apply technique to reduce VIMS in virtual environments and simulators, while vibration applied to the seat is not a successful method.

  15. Role of endogenous opioid peptides in the pathogenesis of motion sickness

    International Nuclear Information System (INIS)

    Yasnetsov, V.V.; Il'ina, S.L.; Karsanova, S.K.; Medvedev, O.S.; Mokrousova, A.V.; Sabaev, V.V.; Shashkov, V.A.; Tigranyan, R.A.; Vakulina, O.P

    1986-01-01

    This paper examines the pathogenesis of motion sickness and the role of the various neurochemical systems of the body in the genesis of the condition. It has been shown that the endogenous opioid system participates in the genesis of several pathological processes; this was the motivation for the study. The plasma beta-endorphin level was determined in samples from 19 clinically healthy males. Considering the positive prophylactic and therapeutic effect of naloxone against motion sickness it can be postulated that endogenous opioid peptides participate in the genesis of the vestibulo-autonomic disorders in motion sickness

  16. Role of endogenous opioid peptides in the pathogenesis of motion sickness

    Energy Technology Data Exchange (ETDEWEB)

    Yasnetsov, V.V.; Il' ina, S.L.; Karsanova, S.K.; Medvedev, O.S.; Mokrousova, A.V.; Sabaev, V.V.; Shashkov, V.A.; Tigranyan, R.A.; Vakulina, O.P

    1986-01-01

    This paper examines the pathogenesis of motion sickness and the role of the various neurochemical systems of the body in the genesis of the condition. It has been shown that the endogenous opioid system participates in the genesis of several pathological processes; this was the motivation for the study. The plasma beta-endorphin level was determined in samples from 19 clinically healthy males. Considering the positive prophylactic and therapeutic effect of naloxone against motion sickness it can be postulated that endogenous opioid peptides participate in the genesis of the vestibulo-autonomic disorders in motion sickness.

  17. Autogenic Feedback Training Exercise: Controlling Physiological Responses to Mitigate Motion Sickness

    Science.gov (United States)

    Walton, Nia; Spencer, Telissa; Cowings, Patricia; Toscano, William B.

    2018-01-01

    During space travel approximately 50 of the crew experience symptoms of motion sickness that can range from mild forms of nausea or dizziness to severe malaise and vomiting1. Developing an effective treatment for these symptoms has become a priority of the National Aeronautics and Space Administration (NASA). Autogenic-Feedback Training Exercise (AFTE) is a nonpharmacological countermeasure for mitigating motion sickness. It involves training subjects to control physiological responses in high stress environments2. The primary goal of this experiment is to evaluate the effectiveness of AFTE for increasing tolerance to motion sickness in high stress environments.

  18. Assessment of otolith function using cervical and ocular vestibular evoked myogenic potentials in individuals with motion sickness.

    Science.gov (United States)

    Singh, Niraj Kumar; Pandey, Preeti; Mahesh, Soumya

    2014-01-01

    The involvement of otolith organs in motion sickness has long been debated; however, equivocal findings exist in literature. The present study thus aimed at evaluating the otolith functioning in individuals with motion sickness. Cervical and ocular vestibular evoked myogenic potentials were recorded from 30 individuals with motion sickness, 30 professional drivers and 30 healthy individuals. The results revealed no significant difference in latencies and amplitudes between the groups (p>0.05). Nonetheless, thresholds were significantly elevated and inter-aural asymmetry ratio significantly higher in motion sickness susceptible group (p otolithic function seem the likely reasons behind motion sickness susceptibility.

  19. Control of a virtual ambulation influences body movement and motion sickness

    Directory of Open Access Journals (Sweden)

    Hagstrom Jens

    2011-12-01

    Full Text Available Drivers typically are less susceptible to motion sickness than passengers. The influence of vehicle control has theoretical implications for the etiology of motion sickness, and has practical implications for the design of virtual environments. In the present study, participants either controlled or did not control a nonvehicular virtual avatar (i.e., an ambulatory character in a console video game. We examined the incidence of motion sickness and patterns of movement of the head and torso as participants either played or watched the game. Motion sickness incidence was lower when controlling the virutal avatar than when watching an avatar that was controlled by someone else. Patterns of head and torso movement differed between particpants who did and did not control the avatar. Indepenently, patterns of movement differed between participants who reported motion sickness and those who did not. The results suggest that motion sickness is influenced by control of stimulus motion, whether that motion arises from a vehicle or from any other source. We consider implications for the design of humancomputer interfaces.

  20. The effect of autogenic training and biofeedback on motion sickness tolerance.

    Science.gov (United States)

    Jozsvai, E E; Pigeau, R A

    1996-10-01

    Motion sickness is characterized by symptoms of vomiting, drowsiness, fatigue and idiosyncratic changes in autonomic nervous system (ANS) responses such as heart rate (HR) and skin temperature (ST). Previous studies found that symptoms of motion sickness are controllable through self-regulation of ANS responses and the best method to teach such control is autogenic-feedback (biofeedback) training. Recent experiments indicated that biofeedback training is ineffective in reducing symptoms of motion sickness or in increasing tolerance to motion. If biofeedback facilitates learning of ANS self-regulation then autogenic training with true feedback (TFB) should lead to better control over ANS responses and better motion tolerance than autogenic training with false feedback (FFB). If there is a relationship between ANS self-regulation and coping with motion stress, a significant correlation should be found between amounts of control over ANS responses and measures of motion tolerance and/or symptoms of motion sickness. There were 3 groups of 6 subjects exposed for 6 weeks to weekly sessions of Coriolis stimulation to induce motion sickness. Between the first and second Coriolis sessions, subjects in the experimental groups received five episodes of autogenic training with either true (group TFB) or false (group FFB) feedback on their HR and ST. The control group (CTL) received no treatment. Subjects learned to control their HR and ST independent of whether they received true or false feedback. Learned control of ST and HR was not related to severity of motion sickness or subject's ability to withstand Coriolis stimulation following treatment. A lack of significant correlation between these variables suggested that subjects were not able to apply their skills of ANS self-regulation in the motion environment, and/ or such skills had little value in reducing symptoms of motion sickness or enhancing their ability to withstand rotations.

  1. Autogenic-Feedback Training for the Control of Space Motion Sickness

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, W. B.

    1994-01-01

    This paper presents case-studies of 9 shuttle crewmembers (prime and alternates) and one U.S. Navy F-18 pilot, as they participated in all preflight training and testing activities in support of a life sciences flight experiment aboard Spacelab-J, and Spacelab-3. The primary objective of the flight experiment was to determine if Autogenic-feedback training (AFT), a physiological self-regulation training technique would be an effective treatment for motion sickness and space motion sickness in these crewmembers. Additional objectives of this study involved the examining human physiological responses to motion sickness on Earth and in space, as well as developing predictive criteria for susceptibility to space motion sickness based on ground-based data. Comparisons of these crewmembers are made to a larger set of subjects from previous experiments (treatment and "test-only" controls subjects). This paper describes all preflight methods, results and proposed changes for future tests.

  2. Control of a Virtual Vehicle Influences Postural Activity and Motion Sickness

    Science.gov (United States)

    Dong, Xiao; Yoshida, Ken; Stoffregen, Thomas A.

    2011-01-01

    Everyday experience suggests that drivers are less susceptible to motion sickness than passengers. In the context of inertial motion (i.e., physical displacement), this effect has been confirmed in laboratory research using whole body motion devices. We asked whether a similar effect would occur in the context of simulated vehicles in a visual…

  3. Behavioral methods of alleviating motion sickness: effectiveness of controlled breathing and a music audiotape.

    Science.gov (United States)

    Yen Pik Sang, Fleur D; Billar, Jessica P; Golding, John F; Gresty, Michael A

    2003-01-01

    Behavioral countermeasures for motion sickness would be advantageous because of the side effects of antiemetic drugs, but few alternative treatments are available. The objective of this study was to compare the effectiveness of controlling breathing and listening to a music audiotape designed to reduce motion sickness symptoms, on increasing tolerance to motion-induced nausea. Twenty-four healthy subjects were exposed to nauseogenic Coriolis stimulation on a rotating turntable under three conditions: whilst focusing on controlling breathing; listening to a music audiotape; or without intervention (control). The three conditions were performed by each subject according to a replicated factorial design at 1-week intervals at the same time of day. Ratings of motion sickness were obtained every 30 seconds. Once a level of mild nausea was reached subjects commenced controlling breathing or listened to the music audiotape. Motion was stopped after the onset of moderate nausea. Mean (+/- SD) motion exposure time in minutes tolerated before the onset of moderate nausea was significantly longer (p music (10.4 +/- 5.6 min) compared with control (9.2 +/- 5.9 min). Both controlling breathing and the music audiotape provided significant protection against motion sickness and with similar effectiveness. These nonpharmacologic countermeasures are only half as effective as standard doses of anti-motion sickness drugs, such as oral scopolamine; however, they are easy to implement and free of side effects.

  4. Relationship between motion sickness, migraine and menstruation in crew members of a "round the world" yacht race.

    Science.gov (United States)

    Grunfeld, E; Gresty, M A

    1998-11-15

    The similarities between the symptoms reported by patients with migraine and those experienced by severely motion sick individuals raises the question of whether the two conditions involve common mechanisms. In women, attacks of migraine may follow the menstrual cycle, and anecdote suggests this may also be true of motion sickness. The aim of this study was to determine whether there was a cyclical pattern in the occurrence of migraine/headache and motion sickness among crew members of a "round the world" yacht race. The participants were asked to complete pre- and postrace questionnaires that related to their susceptibility to motion sickness and headache/migraine; additionally, the female subjects were asked for details about their menstrual cycle. During the race the subjects completed a logbook to record the occurrence of motion sickness (using a four-point scale), migraine/headache (including the type of headache), menstruation, medication consumption and duties aboard the yacht. Female sailors were found to be more prone to motion sickness than the males. Motion sickness was also found to be linked to time at sea, and subjects who suffered migraine during the race were also more susceptible to motion sickness. A distinct pattern was found in the occurrence of motion sickness and headache that related to the menstrual cycle, although motion sickness and headache did not generally occur together in most of the subjects. A cyclical pattern was not obvious for the male subjects.

  5. The influence of sleep deprivation and oscillating motion on sleepiness, motion sickness, and cognitive and motor performance.

    Science.gov (United States)

    Kaplan, Janna; Ventura, Joel; Bakshi, Avijit; Pierobon, Alberto; Lackner, James R; DiZio, Paul

    2017-01-01

    Our goal was to determine how sleep deprivation, nauseogenic motion, and a combination of motion and sleep deprivation affect cognitive vigilance, visual-spatial perception, motor learning and retention, and balance. We exposed four groups of subjects to different combinations of normal 8h sleep or 4h sleep for two nights combined with testing under stationary conditions or during 0.28Hz horizontal linear oscillation. On the two days following controlled sleep, all subjects underwent four test sessions per day that included evaluations of fatigue, motion sickness, vigilance, perceptual discrimination, perceptual learning, motor performance and learning, and balance. Sleep loss and exposure to linear oscillation had additive or multiplicative relationships to sleepiness, motion sickness severity, decreases in vigilance and in perceptual discrimination and learning. Sleep loss also decelerated the rate of adaptation to motion sickness over repeated sessions. Sleep loss degraded the capacity to compensate for novel robotically induced perturbations of reaching movements but did not adversely affect adaptive recovery of accurate reaching. Overall, tasks requiring substantial attention to cognitive and motor demands were degraded more than tasks that were more automatic. Our findings indicate that predicting performance needs to take into account in addition to sleep loss, the attentional demands and novelty of tasks, the motion environment in which individuals will be performing and their prior susceptibility to motion sickness during exposure to provocative motion stimulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Evaluation of adaptation to visually induced motion sickness based on the maximum cross-correlation between pulse transmission time and heart rate

    Directory of Open Access Journals (Sweden)

    Chiba Shigeru

    2007-09-01

    Full Text Available Abstract Background Computer graphics and virtual reality techniques are useful to develop automatic and effective rehabilitation systems. However, a kind of virtual environment including unstable visual images presented to wide field screen or a head mounted display tends to induce motion sickness. The motion sickness induced in using a rehabilitation system not only inhibits effective training but also may harm patients' health. There are few studies that have objectively evaluated the effects of the repetitive exposures to these stimuli on humans. The purpose of this study is to investigate the adaptation to visually induced motion sickness by physiological data. Methods An experiment was carried out in which the same video image was presented to human subjects three times. We evaluated changes of the intensity of motion sickness they suffered from by a subjective score and the physiological index ρmax, which is defined as the maximum cross-correlation coefficient between heart rate and pulse wave transmission time and is considered to reflect the autonomic nervous activity. Results The results showed adaptation to visually-induced motion sickness by the repetitive presentation of the same image both in the subjective and the objective indices. However, there were some subjects whose intensity of sickness increased. Thus, it was possible to know the part in the video image which related to motion sickness by analyzing changes in ρmax with time. Conclusion The physiological index, ρmax, will be a good index for assessing the adaptation process to visually induced motion sickness and may be useful in checking the safety of rehabilitation systems with new image technologies.

  7. Autogenic-feedback training - A treatment for motion and space sickness

    Science.gov (United States)

    Cowings, Patricia S.

    1990-01-01

    A training method for preventing the occurrence of motion sickness in humans, called autogenic-feedback training (AFT), is described. AFT is based on a combination of biofeedback and autogenic therapy which involves training physiological self-regulation as an alternative to pharmacological management. AFT was used to reliably increase tolerance to motion-sickness-inducing tests in both men and women ranging in age from 18 to 54 years. The effectiveness of AFT is found to be significantly higher than that of protective adaptation training. Data obtained show that there is no apparent effect from AFT on measures of vestibular perception and no side effects.

  8. Autogenic-Feedback Training (AFT) as a preventive method for space motion sickness: Background and experimental design

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.

    1993-01-01

    Finding an effective treatment for the motion sickness-like symptoms that occur in space has become a high priority for NASA. The background research is reviewed and the experimental design of a formal life sciences shuttle flight experiment designed to prevent space motion sickness in shuttle crew members is presented. This experiment utilizes a behavioral medicine approach to solving this problem. This method, Autogenic-Feedback Training (AFT), involves training subjects to voluntarily control several of their own physiological responses to environmental stressors. AFT has been used reliably to increase tolerance to motion sickness during ground-based tests in over 200 men and women under a variety of conditions that induce motion sickness, and preliminary evidence from space suggests that AFT may be an effective treatment for space motion sickness as well. Proposed changes to this experiment for future manifests are included.

  9. The efficacy of airflow and seat vibration on reducing visually induced motion sickness

    NARCIS (Netherlands)

    D’Amour, Sarah; Bos, Jelte E.; Keshavarz, Behrang

    2017-01-01

    Visually induced motion sickness (VIMS) is a well-known sensation in virtual environments and simulators, typically characterized by a variety of symptoms such as pallor, sweating, dizziness, fatigue, and/or nausea. Numerous methods to reduce VIMS have been previously introduced; however, a reliable

  10. The effect of internal and external fields of view on visually induced motion sickness

    NARCIS (Netherlands)

    Bos, J.E.; Vries, S.C. de; Emmerik, M.L. van; Groen, E.L.

    2010-01-01

    Field of view (FOV) is said to affect visually induced motion sickness. FOV, however, is characterized by an internal setting used by the graphics generator (iFOV) and an external factor determined by screen size and viewing distance (eFOV). We hypothesized that especially the incongruence between

  11. Orientation Preferences and Motion Sickness Induced in a Virtual Reality Environment.

    Science.gov (United States)

    Chen, Wei; Chao, Jian-Gang; Zhang, Yan; Wang, Jin-Kun; Chen, Xue-Wen; Tan, Cheng

    2017-10-01

    Astronauts' orientation preferences tend to correlate with their susceptibility to space motion sickness (SMS). Orientation preferences appear universally, since variable sensory cue priorities are used between individuals. However, SMS susceptibility changes after proper training, while orientation preferences seem to be intrinsic proclivities. The present study was conducted to investigate whether orientation preferences change if susceptibility is reduced after repeated exposure to a virtual reality (VR) stimulus environment that induces SMS. A horizontal supine posture was chosen to create a sensory context similar to weightlessness, and two VR devices were used to produce a highly immersive virtual scene. Subjects were randomly allocated to an experimental group (trained through exposure to a provocative rotating virtual scene) and a control group (untrained). All subjects' orientation preferences were measured twice with the same interval, but the experimental group was trained three times during the interval, while the control group was not. Trained subjects were less susceptible to SMS, with symptom scores reduced by 40%. Compared with untrained subjects, trained subjects' orientation preferences were significantly different between pre- and posttraining assessments. Trained subjects depended less on visual cues, whereas few subjects demonstrated the opposite tendency. Results suggest that visual information may be inefficient and unreliable for body orientation and stabilization in a rotating visual scene, while reprioritizing preferences for different sensory cues was dynamic and asymmetric between individuals. The present findings should facilitate customization of efficient and proper training for astronauts with different sensory prioritization preferences and dynamic characteristics.Chen W, Chao J-G, Zhang Y, Wang J-K, Chen X-W, Tan C. Orientation preferences and motion sickness induced in a virtual reality environment. Aerosp Med Hum Perform. 2017

  12. Reducing motion sickness - A comparison of autogenic-feedback training and an alternative cognitive task

    Science.gov (United States)

    Toscano, W. B.; Cowings, P. S.

    1982-01-01

    Eighteen men were randomly assigned to three groups matched for susceptibility to Coriolis motion sickness. All subjects were given six Coriolis Sickness Susceptibility Index (CSSI) tests separated by 5-d intervals. Treatment Group I subjects were taught to control their own autonomic responses before the third, fourth, and fifth CSSI tests (6 h total training). Group II subjects were given 'sham' training in an alternative cognitive task under conditions otherwise identical to those of Group I. Group III subjects received no treatment. Results showed that Group I subjects could withstand the stress of Coriolis acceleration significantly longer after training. Neither of the other two groups changed significantly.

  13. A heuristic mathematical model for the dynamics of sensory conflict and motion sickness

    Science.gov (United States)

    Oman, C. M.

    1982-01-01

    By consideration of the information processing task faced by the central nervous system in estimating body spatial orientation and in controlling active body movement using an internal model referenced control strategy, a mathematical model for sensory conflict generation is developed. The model postulates a major dynamic functional role for sensory conflict signals in movement control, as well as in sensory-motor adaptation. It accounts for the role of active movement in creating motion sickness symptoms in some experimental circumstance, and in alleviating them in others. The relationship between motion sickness produced by sensory rearrangement and that resulting from external motion disturbances is explicitly defined. A nonlinear conflict averaging model is proposed which describes dynamic aspects of experimentally observed subjective discomfort sensation, and suggests resulting behaviours. The model admits several possibilities for adaptive mechanisms which do not involve internal model updating. Further systematic efforts to experimentally refine and validate the model are indicated.

  14. Vection is the main contributor to motion sickness induced by visual yaw rotation: Implications for conflict and eye movement theories.

    Directory of Open Access Journals (Sweden)

    Suzanne A E Nooij

    Full Text Available This study investigated the role of vection (i.e., a visually induced sense of self-motion, optokinetic nystagmus (OKN, and inadvertent head movements in visually induced motion sickness (VIMS, evoked by yaw rotation of the visual surround. These three elements have all been proposed as contributing factors in VIMS, as they can be linked to different motion sickness theories. However, a full understanding of the role of each factor is still lacking because independent manipulation has proven difficult in the past. We adopted an integrative approach to the problem by obtaining measures of potentially relevant parameters in four experimental conditions and subsequently combining them in a linear mixed regression model. To that end, participants were exposed to visual yaw rotation in four separate sessions. Using a full factorial design, the OKN was manipulated by a fixation target (present/absent, and vection strength by introducing a conflict in the motion direction of the central and peripheral field of view (present/absent. In all conditions, head movements were minimized as much as possible. Measured parameters included vection strength, vection variability, OKN slow phase velocity, OKN frequency, the number of inadvertent head movements, and inadvertent head tilt. Results show that VIMS increases with vection strength, but that this relation varies among participants (R2 = 0.48. Regression parameters for vection variability, head and eye movement parameters were not significant. These results may seem to be in line with the Sensory Conflict theory on motion sickness, but we argue that a more detailed definition of the exact nature of the conflict is required to fully appreciate the relationship between vection and VIMS.

  15. A Review of Motion Sickness with Special Reference to Simulator Sickness

    Science.gov (United States)

    1985-04-15

    intuitive, neo-Freudian and neo- Pavlovian ! Although there are no hard data to support the supposition that anxiety is a provocative stimulus for motion...with increased cholinergic activity (Koelle. 1965) and decreased adrenergic. but the relationships aro not cleat-cut (Tang, 1970). While the drugs

  16. An Evaluation of the Frequency and Severity of Motion Sickness Incidences in Personnel Within the Command and Control Vehicle (C2V)

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.; DeRoshia, Charles

    1998-01-01

    The purpose of this study was to assess the frequency and severity of motion sickness in personnel during a field exercise in the Command and Control Vehicle (C2V). This vehicle contains four workstations where military personnel are expected to perform command decisions in the field during combat conditions. Eight active duty military men (U.S. Army) at the Yuma Proving Grounds in Arizona participated in this study. All subjects were given baseline performance tests while their physiological responses were monitored on the first day. On the second day of their participation, subjects rode in the C2V while their physiological responses and performance measures were recorded. Self-reports of motion sickness were also recorded. Results showed that only one subject experienced two incidences of emesis. However, seven out of the eight subjects reported other motion sickness symptoms; most predominant was the report of drowsiness, which occurred a total of 19 times. Changes in physiological responses were observed relative to motion sickness symptoms reported and the different environmental conditions (i.e., level, hills, gravel) during the field exercise. Performance data showed an overall decrement during the C2V exercise. These findings suggest that malaise and severe drowsiness can potentially impact the operational efficiency of the C2V crew. It was concluded that conflicting sensory information from the subject's visual displays and movements of the vehicle during the field exercise significantly contributed to motion sickness symptoms. It was recommended that a second study be conducted to further evaluate the impact of seat position or orientation and C2V experience on motion sickness susceptibility. Further, it was recommended that an investigation be performed on behavioral methods for improving crew alertness, motivation, and performance and for reducing malaise.

  17. The effect of internal and external fields of view on visually induced motion sickness.

    Science.gov (United States)

    Bos, Jelte E; de Vries, Sjoerd C; van Emmerik, Martijn L; Groen, Eric L

    2010-07-01

    Field of view (FOV) is said to affect visually induced motion sickness. FOV, however, is characterized by an internal setting used by the graphics generator (iFOV) and an external factor determined by screen size and viewing distance (eFOV). We hypothesized that especially the incongruence between iFOV and eFOV would lead to sickness. To that end we used a computer game environment with different iFOV and eFOV settings, and found the opposite effect. We speculate that the relative large differences between iFOV and eFOV used in this experiment caused the discrepancy, as may be explained by assuming an observer model controlling body motion. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. A Comparison of Intranasal and Oral Scopolamine for Motion Sickness Prevention in Military Personnel

    Science.gov (United States)

    2008-08-18

    G., Ho, T., Lee, S., Manaretto, J., & Tsai, C. (2003). Transdermal scopolamine drug delivery systems for motion sickness. Retrieved August 14, 2007...earlier studies, the current study was able to utilize a precise drug delivery system to achieve tight control on the amount of scopolamine administered...widely used medication, and perhaps the most extensively researched, is the anticholinergic drug scopolamine. Scopolamine, in oral and transdermal form

  19. Brain blood-flow changes during motion sickness. [thalamus vascular changes in dogs during swing tests

    Science.gov (United States)

    Johnson, W. H.; Hsuen, J.

    1973-01-01

    The possibility of diminished blood flow in the brain is studied as one of the factors resulting from an increase in skeletal muscle blood volume concomitant with other characteristics of motion sickness. Thermistors are implanted in the thalamus of dogs and blood flow changes are recorded while they are subjected to sinusoidal movement on a two pole swing. Results of these initial steps in a proposed long term exploration of different areas of the brain are presented.

  20. The Effect of Mild Motion Sickness and Sopite Syndrome on Multitasking Cognitive Performance

    Science.gov (United States)

    2013-03-01

    useful as a predictor of performance in occupations such as pilot , where demands on multitasking are presumably high.” 33 It is interesting to assess...Council Committee on Selection and Training of Aircraft Pilots , Executive Subcommittee. Washington, D.C. Wendt, G. R. (1951). Vestibular functions. In S...public release; distribution is unlimited THE EFFECT OF MILD MOTION SICKNESS AND SOPITE SYNDROME ON MULTITASKING COGNITIVE PERFORMANCE by

  1. Virtual reality body motion induced navigational controllers and their effects on simulator sickness and pathfinding.

    Science.gov (United States)

    Aldaba, Cassandra N; White, Paul J; Byagowi, Ahmad; Moussavi, Zahra

    2017-07-01

    Virtual reality (VR) navigation is usually constrained by plausible simulator sickness (SS) and intuitive user interaction. The paper reports on the use of four different degrees of body motion induced navigational VR controllers, a TiltChair, omni-directional treadmill, a manual wheelchair joystick (VRNChair), and a joystick in relation to a participant's SS occurrence and a controller's intuitive utilization. Twenty young adult participants utilized all controllers to navigate through the same VR task environment in separate sessions. Throughout the sessions, SS occurrence was measured from a severity score by a standard SS questionnaire and from body sway by a center of pressure path length with eyes opened and closed. SS occurrence did not significantly differ among the controllers. However, time spent in VR significantly contributed to SS occurrence; hence, a few breaks to minimize SS should be interjected throughout a VR task. For all task trials, we recorded the participant's travel trajectories to investigate each controller's intuitive utilization from a computed traversed distance. Shorter traversed distances indicated that participants intuitively utilized the TiltChair with a slower speed; while longer traversed distances indicated participants struggled to utilize the omni-directional treadmill with a unnaturalistic stimulation of gait. Therefore, VR navigation should use technologies best suited for the intended age group that minimizes SS, and produces intuitive interactions for the participants.

  2. The relationship of motion sickness susceptibility to learned autonomic control for symptom suppression

    Science.gov (United States)

    Cowings, P. S.; Toscano, W. B.

    1982-01-01

    Twenty-four men were randomly assigned to four equal groups matched in terms of their Coriolis Sickness Susceptibility Index (CSSI). Two groups of subjects were highly susceptible to motion sickness, and two groups were moderately susceptible. All subjects were given six C551 tests at 5-d intervals. Treatment Groups I (highly susceptible) and II (moderately susceptible) were taught to control their autonomic responses, using a training method called autogenic-feedback training (AFT) before the third, fourth, and fifth CSSI tests. Control groups III (highly susceptible) and IV (moderately susceptible) received no treatment. Results showed that both treatment groups significantly improved performance on CSSI tests after training; neither of the control groups changed significantly. Highly and moderately susceptible subjects in the two treatment groups improved at comparable rates. Highly susceptible control group subjects did not habituate across tests as readily as the moderately susceptible controls.

  3. Differences in Otolith and Abdominal Viscera Graviceptor Dynamics: Implications for Motion Sickness and Perceived Body Position

    Science.gov (United States)

    vonGierke, Henning E.; Parker, Donald E.

    1993-01-01

    Human graviceptors, located in the trunk by Mittelstaedt probably transduce acceleration by abdominal viscera motion. As demonstrated previously in biodynamic vibration and impact tolerance research the thoraco-abdominal viscera exhibit a resonance at 4 to 6 Hz. Behavioral observations and mechanical models of otolith graviceptor response indicate a phase shift increasing with frequency between 0.01 and O.5 Hz. Consequently the potential exists for intermodality sensory conflict between vestibular and visceral graviceptor signals at least at the mechanical receptor level. The frequency range of this potential conflict corresponds with the primary frequency range for motion sickness incidence in transportation, in subjects rotated about Earth-horizontal axes (barbecue spit stimulation) and in periodic parabolic flight microgravity research and also for erroneous perception of vertical oscillations in helicopters. We discuss the implications of this hypothesis for previous self motion perception research and suggestions for various future studies.

  4. Motion sickness and development of synergy within the spatial orientation system. A hypothetical unifying concept

    Science.gov (United States)

    Guedry, F. E.; Rupert, A. R.; Reschke, M. F.

    1998-01-01

    Adaptation to research paradigms such as rotating rooms and optical alteration of visual feedback during movement results in development of perceptual-motor programs that provide the reflexive assistance that is necessary to skilled control of movement and balance. The discomfort and stomach awareness that occur during the adaptation process has been attributed to conflicting sensory information about the state of motion. Vestibular signals depend on the kinematics of head movements irrespective of the presence or absence of signals from other senses. We propose that sensory conflict when vestibular signals are at least one component of the conflict are innately disturbing and unpleasant. This innate reaction is part of a continuum that operates early in life to prevent development of inefficient perceptual-motor programs. This reaction operates irrespective of and in addition to reward and punishment from parental guidance or goal attainment to yield efficient control of whole body movement in the operating environment of the individual. The same mechanism is involved in adapting the spatial orientation system to strange environments. This conceptual model "explains" why motion sickness is associated with adaptation to novel environments and is in general consistent with motion sickness literature.

  5. Motion Sickness

    Science.gov (United States)

    ... potatoes. Don’t eat greasy, spicy, or acidic foods just before or during travel. Drink plenty of water. Avoid alcohol. Get a ... Conditions Prevention and Wellness Staying Healthy Healthy Living Travel ... myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and ...

  6. The application of virtual reality technology to testing resistance to motion sickness

    Directory of Open Access Journals (Sweden)

    Menshikova G. Ya.

    2017-09-01

    Full Text Available Background. Prolonged exposure to moving images in virtual reality systems can cause virtual reality induced motion sickness (VIMS. The ability to resist motion sickness may be associated with the level of vestibular function development. objective. The aim of the present research is to study the oculomotor characteristics of individuals whose observation of moving virtual environments causes the VIMS effect. We hypothesized that people who have a robust vestibular function as a result of their professional activity, are less susceptible to VIMS than people who have no such professional abilities. The differences in people’s abilities to resist the effects of the virtual environment may be revealed in the oculomotor characteristics registered during their interaction with a virtual environment. Design. Figure skaters, football players, wushu fighters, and non-trained people were tested. e CAVE virtual reality system was used to initiate the VIMS effect. three virtual scenes were constructed consisting of many bright balls moving as a whole around the observer. e scenes differed in the width of the visual field; all balls subtended either 45°, 90° or 180°. Results. The results showed more active eye movements for athletes compared to non-trained people, i.e. an increase in blink, fixation, and saccade counts. A decrease in saccadic amplitudes was revealed for figure skaters. These characteristics were considered specific indicators of the athletes’ ability to resist motion sickness. Conclusions. It was found that the strength of the VIMS effect increased with the increasing width of the visual field. The effectiveness of virtual reality and eye-tracking technologies to test the VIMS effect was demonstrated.

  7. The use of EEG to measure cerebral changes during computer-based motion-sickness-inducing tasks

    Science.gov (United States)

    Strychacz, Christopher; Viirre, Erik; Wing, Shawn

    2005-05-01

    Motion sickness (MS) is a stressor commonly attributed with causing serious navigational and performance errors. The distinct nature of MS suggests this state may have distinct neural markers distinguishable from other states known to affect performance (e.g., stress, fatigue, sleep deprivation, high workload). This pilot study used new high-resolution electro-encephalograph (EEG) technologies to identify distinct neuronal activation changes that occur during MS. Brain EEG activity was monitored while subjects performed a ball-tracking task and viewed stimuli on a projection screen intended to induce motion sickness/spatial disorientation. Results show the presence of EEG spectral changes in all subjects who developed motion sickness when compared to baseline levels. These changes included: 1) low frequency (1 to 10 Hz) changes that may reflect oculomotor movements rather than intra-cerebral sources; 2) increased spectral power across all frequencies (attributable to increased scalp conductivity related to sweating), 3) local increases of power spectra in the 20-50 Hz range (likely attributable to external muscles on the skull) and; 4) a central posterior (occipital) independent component that shows suppression of a 20 Hz peak in the MS condition when compared to baseline. Further research is necessary to refine neural markers, characterize their origin and physiology, to distinguish between motion sickness and other states and to enable markers to be used for operator state monitoring and the designing of interventions for motion sickness.

  8. Histaminergic and cholinergic neuron systems in the impairment of human thermoregulation during motion sickness.

    Science.gov (United States)

    Nobel, Gerard; Tribukait, Arne; Mekjavic, Igor B; Eiken, Ola

    2010-05-31

    Motion sickness (MS) exaggerates body cooling during cold-water immersion. The aim of the present study was to investigate whether such MS-induced predisposition to hypothermia is influenced by two anti-MS drugs: the histamine-receptor blocker dimenhydrinate (DMH) and the muscarine-receptor blocker scopolamine (Scop). Nine healthy male subjects were immersed in 15 degrees C water for a maximum of 90min in five conditions: (1) control (CN): no medication, no MS provocation; (2) MS-control (MS-CN): no medication, MS provocation; (3) MS-placebo (MS-P): placebo DMH and placebo Scop, MS provocation; (4) MS-DMH: DMH and placebo Scop, MS provocation; (5) MS-Scop: Scop and placebo DMH, MS provocation. MS was induced by use of a rotating chair. Throughout the experiments rectal temperature (T(re)), the difference in temperature between the non-immersed right forearm and third finger (T(ff)) as an index of peripheral vasoconstriction, and oxygen uptake (VO(2)) as a measure of shivering thermogenesis, were recorded. DMH and Scop were similarly efficacious in ameliorating nausea. The fall in T(re) was greater in the MS-CN and MS-P conditions than in the CN condition. DMH, but not Scop, prevented the MS-induced increase in body-core cooling. MS attenuated the cold-induced vasoconstriction, an effect which was fully prevented by DMH but only partially by Scop. MS provocation did not affect VO(2) in any condition. The results suggest that the MS-induced predisposition to hypothermia is predominantly mediated by histaminergic mechanisms and that DMH might be useful in conjunction with maritime accidents or other scenarios where exposure to cold and MS are imminent features. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  9. A Historical View of Motion Sickness-A Plague at Sea and on Land, Also with Military Impact.

    Science.gov (United States)

    Huppert, Doreen; Benson, Judy; Brandt, Thomas

    2017-01-01

    Seasickness and its triggers, symptoms, and preventive measures were well known in antiquity. This chapter is based on an analysis of descriptions of motion sickness, in particular seasickness, in ancient Greek, Roman, and Chinese literature. A systematic search was made from the Greek period beginning with Homer in 800 BC to the late Roman period and ending with Aetios Amidenos in 600 AD, as well as in the Chinese medical classics dating from around 300 AD. Major aspects are the following: body movements caused by waves were identified in all cultures as the critical stimuli. The ancient Greeks and Romans knew that other illnesses and the mental state could precipitate seasickness and that experienced sailors were highly resistant to it (habituation). The Chinese observed that children were particularly susceptible to motion sickness; they first described the type of motion sickness induced by traveling in carts (cart-sickness) or being transported on a litter or in a sedan chair (litter-sickness). The western classics recommended therapeutic measures like fasting or specific diets, pleasant fragrancies, medicinal plants like white hellebore (containing various alkaloids), or a mixture of wine and wormwood. The East knew more unusual measures, such as drinking the urine of young boys, swallowing white sand-syrup, collecting water drops from a bamboo stick, or hiding earth from the kitchen hearth under the hair. The Greek view of the pathophysiology of seasickness was based on the humoral theory of Empedokles and Aristoteles and differed from the Chinese medicine of correspondences, which attributed malfunctions to certain body substances and the life force Qi. Many sources emphasized the impact of seasickness on military actions and famous naval battles such as the Battle of the Red Cliff, which marked the end of the Han dynasty in China, or the defeat of the Spanish Armada by the English in 1588. A peculiar form of motion sickness is associated with Napoleon

  10. First intramuscular administration in the U.S. space program. [of motion sickness drugs

    Science.gov (United States)

    Bagian, James P.

    1991-01-01

    In the past, the only kind of medicines used for symptomatic treatment of space motion sickness (SMS) in space had been oral, transdermal, or suppositories. This paper describes the effect of the first intramuscular (IM) administration of Phenergan (50-mg in single dose) on SMS in one subject who exhibited grade-3 symptoms and signs which persisted unabated throughout the first and the second flight days aboard the Space Shuttle. Thirty minutes after the injection, the subject had completely recovered. His symptoms were gone, his appetite was back, and he had no recurrences for the remainder of the flight. Since that experiment, intramuscular injections have been given nine more times on subsequent flights, with similar results.

  11. The effects of autogenic-feedback training on motion sickness severity and heart rate variability in astronauts

    Science.gov (United States)

    Toscano, William B.; Cowings, Patricia S.

    1994-01-01

    Space motion sickness (SMS) affects 50 percent of all people during early days of spaceflight. This study describes the results of two Shuttle flight experiments in which autogenic-feedback training (AFT), a physiological conditioning method, was tested as a treatment for this disorder. Of the six who were designated as flight subjects (two women and four men), three were given treatment and three served as controls (i.e., no AFT). Treatment subjects were given 6 hours of preflight AFT. Preflight results showed that AFT produced a significant increase in tolerance to rotating chair motion sickness tests. Further, this increased tolerance was associated with changes in specific physiological responses and reports of reduced malaise. Flight results showed that two of the three control subjects experienced repeated vomiting on the first mission day, while one subject experienced only moderate malaise. Of the three treatment subjects, one experienced mild discomfort, one moderate discomfort, and one severe motion sickness. Only the three control subjects took medication for symptom suppression. Measures of cardiac function reflective of vagal control were shown to be affected especially strongly on the first day of space flight. AFT given for control of heart rate, respiration, and other autonomic activity influenced both the vagal control measures and SMS. These data suggest that AFT may be an effective treatment for space motion sickness; however, this cannot be demonstrated conclusively with the small number of subjects described.

  12. NASA-Navy Telemedicine: Autogenic Feedback Training Exercises for Motion Sickness

    Science.gov (United States)

    Acromite, Michael T.; Cowings, Patricia; Toscano, William; Davis, Carl; Porter, Henry O.

    2010-01-01

    Airsickness is the most significant medical condition affecting naval aviation training. A 2001 study showed that airsickness was reported in 81% of naval aviation students and was associated with 82% of below average flight scores. The cost to a single training air-wing was over $150,000 annually for fuel and maintenance costs alone. Resistent cases are sent to the Naval Aerospace Medical Institute (NAMI) for evaluation and desensitization in the self-paced airsickness desensitization (SPAD) program. This approach is 75% successful, but can take up to 8 weeks at a significant travel cost. NASA Ames Research Center's Autogenic Feedback Training Exercises (AFTE) uses physiological and biofeedback training for motion sickness prevention. It has a remote capability that has been used from Moffett Field, CA to Atlanta, GA . AFTE is administered in twelve (30-minute) training sessions. The success rate for the NASA AFTE program has been over 85%. Methods: Implementation Phases: Phase I: Transfer NASA AFTE to NAMI; NASA will remotely train aviation students at NAMI. Phase II: NAMI-centered AFTE application with NASA oversight. Phase III: NAMI-centered AFTE to remotely train at various Navy sites. Phase IV: NAMI to offer Tri-service application and examine research opportunities. Results: 1. Use available telemedicine connectivity between NAMI and NASA. 2. Save over $2,000 per student trained. 3. Reduce aviation training attrition. 4. Provide standardization of multi-location motion sickness training. 5. Future tri-service initiatives. 6. Data to NASA and Navy for QA and research opportunities.

  13. EEG based time and frequency dynamics analysis of visually induced motion sickness (VIMS).

    Science.gov (United States)

    Arsalan Naqvi, Syed Ali; Badruddin, Nasreen; Jatoi, Munsif Ali; Malik, Aamir Saeed; Hazabbah, Wan; Abdullah, Baharudin

    2015-12-01

    3D movies are attracting the viewers as they can see the objects flying out of the screen. However, many viewers have reported various problems which are usually faced after watching 3D movies. These problems include visual fatigue, eye strain, headaches, dizziness, blurred vision or collectively may be termed as visually induced motion sickness (VIMS). This research focuses on the comparison between 3D passive technology with a conventional 2D technology to find that whether 3D is causing trouble in the viewers or not. For this purpose, an experiment was designed in which participants were randomly assigned to watch 2D or a 3D movie. The movie was specially designed to induce VIMS. The movie was shown for the duration of 10 min to every participant. The electroencephalogram (EEG) data was recorded throughout the session. At the end of the session, participants rated their feelings using simulator sickness questionnaire (SSQ). The SSQ data was analyzed and the ratings of 2D and 3D participants were compared statistically by using a two tailed t test. From the SSQ results, it was found that participants watching 3D movies reported significantly higher symptoms of VIMS (p value EEG data was analyzed by using MATLAB and topographic plots are created from the data. A significant difference has been observed in the frontal-theta power which increases with the passage of time in 2D condition while decreases with time in 3D condition. Also, a decrease in beta power has been found in the temporal lobe of 3D group. Therefore, it is concluded that there are negative effects of 3D movies causing significant changes in the brain activity in terms of band powers. This condition leads to produce symptoms of VIMS in the viewers.

  14. Adaptive Changes In Postural Equilibrium And Motion Sickness Following Repeated Exposures To Virtual Environments

    Science.gov (United States)

    Harm, D. L.; Taylor, L. C.

    2006-01-01

    Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Changes in the environmental sensory stimulus conditions and the way we interact with the new stimuli may result in motion sickness, and perceptual, spatial orientation and sensorimotor disturbances. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. Adaptation is revealed by aftereffects including perceptual disturbances and sensorimotor control disturbances. The purpose of the current study was to compare disturbances in postural control produced by dome and head-mounted virtual environment displays, and to examine the effects of exposure duration, and repeated exposures to VR systems. Forty-one subjects (21 men, 20 women) participated in the study with an age range of 21-49 years old. One training session was completed in order to achieve stable performance on the posture and VR tasks before participating in the experimental sessions. Three experimental sessions were performed each separated by one day. The subjects performed a navigation and pick and place task in either a dome or head-mounted display

  15. Assessment of Evidence Base from Medical Debriefs Data on Space Motion Sickness Incidence and Treatment

    Science.gov (United States)

    Younker, D.R.; Daniels, V.R.; Boyd, J.L.; Putcha, L.

    2008-01-01

    An objective of this data compilation and analysis project is to examine incidence and treatment efficacy of common patho-physiological disturbances during spaceflight. Analysis of medical debriefs data indicated that astronauts used medications to alleviate symptoms of four major ailments for which astronauts received treatment for sleep disturbances, space motion sickness (SMS), pain (headache, back pain) and sinus congestion. In the present data compilation and analysis project on SMS treatment during space missions, subject demographics (gender, age, first-time or repeat flyer), incidence and severity of SMS symptoms and subjective treatment efficacy from 317 crewmember debrief records were examined from STS-1 through STS-89. Preliminary analysis of data revealed that 50% of crew members reported SMS symptoms on at least one flight and 22% never experienced it. In addition, there were 387 medication dosing episodes reported, and promethazine was the most commonly used medication. Results of analysis of symptom check lists, medication use/efficacy and gender and flight record differences in incidence and treatment efficacy will be presented. Evidence gaps for treatment efficacy along with medication use trend analysis will be identified.

  16. Does 3D produce more symptoms of visually induced motion sickness?

    Science.gov (United States)

    Naqvi, Syed Ali Arsalan; Badruddin, Nasreen; Malik, Aamir Saeed; Hazabbah, Wan; Abdullah, Baharudin

    2013-01-01

    3D stereoscopy technology with high quality images and depth perception provides entertainment to its viewers. However, the technology is not mature yet and sometimes may have adverse effects on viewers. Some viewers have reported discomfort in watching videos with 3D technology. In this research we performed an experiment showing a movie in 2D and 3D environments to participants. Subjective and objective data are recorded and compared in both conditions. Results from subjective reporting shows that Visually Induced Motion Sickness (VIMS) is significantly higher in 3D condition. For objective measurement, ECG data is recorded to find the Heart Rate Variability (HRV), where the LF/HF ratio, which is the index of sympathetic nerve activity, is analyzed to find the changes in the participants' feelings over time. The average scores of nausea, disorientation and total score of SSQ show that there is a significant difference in the 3D condition from 2D. However, LF/HF ratio is not showing significant difference throughout the experiment.

  17. Reassessment of area postrema's role in motion sickness and conditioned taste aversion

    Science.gov (United States)

    Daunton, Nancy G.; Brizzee, Kenneth R.; Corcoran, Meryl Lee; Crampton, G. H.; Damelio, F.; Elfar, S.; Fox, Robert A.

    1991-01-01

    On the basis of classical studies on the role of the area psotrema (AP) in motion-induced emesis it was generally accepted that the AP is an essential structure for the production of vomiting in response to motion. However, in more recent studies it has been demonstrated that vomiting induced by motion can still occur in animals in which the AP has been destroyed bilaterally. It was inferred from some of these more recent studies that the AP plays no role in motion-induced emesis. From the standpoint of the current understanding of central nervous system (CNS) plasticity, redundancy, remodeling, unmasking, regeneration, and recovery of function, however, it is important to realize the limitations of using ablation procedures to determine the functional role of a given neural structure in a highly integrated, adaptable central nervous system (CNS). For example, the results of our recent investigations in cat and squirrel monkey on the role of the AP in emesis and conditioned taste aversion induced by motion indicate that while AP lesions do not prevent motion-induced emesis when animals are tested 30 days or more after surgery, the lesions do change the latency to emesis. Thus, contradictory findings from lesion studies must be evaluated not only in terms of species difference, differences in lesioning techniques and extent of lesions, and in stimulus parameters, but also in terms of duration of the recovery period, during which significant recovery of function may take place. In our judgment, inadequate consideration of the foregoing factors could lead to erroneous inferences about given structure's role in the behavior of the intact, nonablated animal.

  18. Investigating student understanding of simple harmonic motion

    Science.gov (United States)

    Somroob, S.; Wattanakasiwich, P.

    2017-09-01

    This study aimed to investigate students’ understanding and develop instructional material on a topic of simple harmonic motion. Participants were 60 students taking a course on vibrations and wave and 46 students taking a course on Physics 2 and 28 students taking a course on Fundamental Physics 2 on the 2nd semester of an academic year 2016. A 16-question conceptual test and tutorial activities had been developed from previous research findings and evaluated by three physics experts in teaching mechanics before using in a real classroom. Data collection included both qualitative and quantitative methods. Item analysis and whole-test analysis were determined from student responses in the conceptual test. As results, most students had misconceptions about restoring force and they had problems connecting mathematical solutions to real motions, especially phase angle. Moreover, they had problems with interpreting mechanical energy from graphs and diagrams of the motion. These results were used to develop effective instructional materials to enhance student abilities in understanding simple harmonic motion in term of multiple representations.

  19. Evaluation of ride-quality and incidence of seasickness. 4. Motion sickness incidence and change of facial expression; Senpaku no norigokochi hyoka ni kansuru kenkyu ( 4 ). Norimonoyoi hasshoji no hyojo no henka

    Energy Technology Data Exchange (ETDEWEB)

    Arima, M.; Hirai, T.; Hosoda, R. [Osaka City Univ. (Japan)

    1998-12-31

    This paper studies the method of predicting and evaluating the motion sickness incidence from subject`s facial expressions during the whole-body exposure to oscillations. The facial expressions are recorded with a video camera which can measure them without invasion physiologically and mentally. Facial parameters, which are considered to relate to the motion sickness incidence, are selected, measured and analyzed quantitatively, and a method of evaluating the motion sickness incidence objectively from the facial expressions is proposed. Three facial expression parameters now selected to evaluate the motion sickness incidence are brow width, eye opening and mouth opening. It was clarified that the motion sickness incidence could be expressed joining the above parameters together. This paper consists of three sections, viz. Oscillation experiment for ride-quality evaluation, Measurement and analysis of facial expressions, and Modeling for evaluating facial expressions. 11 refs., 5 figs., 5 tabs.

  20. Artifacts produced during electrical stimulation of the vestibular nerve in cats. [autonomic nervous system components of motion sickness

    Science.gov (United States)

    Tang, P. C.

    1973-01-01

    Evidence is presented to indicate that evoked potentials in the recurrent laryngeal, the cervical sympathetic, and the phrenic nerve, commonly reported as being elicited by vestibular nerve stimulation, may be due to stimulation of structures other than the vestibular nerve. Experiments carried out in decerebrated cats indicated that stimulation of the petrous bone and not that of the vestibular nerve is responsible for the genesis of evoked potentials in the recurrent laryngeal and the cervical sympathetic nerves. The phrenic response to electrical stimulation applied through bipolar straight electrodes appears to be the result of stimulation of the facial nerve in the facial canal by current spread along the petrous bone, since stimulation of the suspended facial nerve evoked potentials only in the phrenic nerve and not in the recurrent laryngeal nerve. These findings indicate that autonomic components of motion sickness represent the secondary reactions and not the primary responses to vestibular stimulation.

  1. An Arduino Investigation of Simple Harmonic Motion

    Science.gov (United States)

    Galeriu, Calin; Edwards, Scott; Esper, Geoffrey

    2014-03-01

    We cannot hope for a new generation of scientists and engineers if we don't let our young students take ownership of their scientific and engineering explorations, if we don't let them enjoy the hands-on cycle of design and production, and if we don't let them implant their creativity into a technologically friendly environment. With this educational philosophy in mind, Massimo Banzi and his team have developed and popularized the open source Arduino microcontroller board. The Arduino board has helped countless people in their science, electronics, robotics, or engineering projects, allowing them to build things that we have not even dreamed of. Physics instructors have also realized the advantages of using Arduino boards for lab experiments. The schools are saving money because the homemade experimental equipment is much cheaper than the commercial alternatives. The students are thankful for an educational experience that is more interesting, more loaded with STEM content, and more fun. As further proof of this new trend in physics education, Vernier5 is now documenting the use of their probes with Arduino boards. This is why we have developed an Arduino-based physics investigation of the simple harmonic motion (SHM) of a mass on a spring. The experimental data are collected with the help of an ultrasonic distance sensor and an Arduino Uno board. The data are then graphed and analyzed using Origin 9. This rich cross-curricular STEM activity integrates electronics, computer programming, physics, and mathematics in a way that is both experimentally exciting and intellectually rewarding.

  2. Investigation of wire motion in superconducting magnets

    International Nuclear Information System (INIS)

    Ogitsu, T.; Tsuchiya, K.; Devred, A.

    1990-09-01

    The large Lorentz forces occuring during the excitation of superconducting magnets can provoke sudden motions of wire, which eventually release enough energy to trigger a quench. These wire motions are accompanied by two electromagnetic effects: an induced emf along the moved wire, and a local change in flux caused by the minute dislocation of current. Both effects cause spikes in the coil voltage. Voltage data recorded during the excitation of a superconducting quadrupole magnet which early exhibit such events are here reported. Interpretations of the voltage spikes in terms of energy release are also presented, leading to insights on the spectrum of the disturbances which occur in real magnets. 15 refs

  3. Differential Gene Expression Profile in the Rat Caudal Vestibular Nucleus is Associated with Individual Differences in Motion Sickness Susceptibility.

    Directory of Open Access Journals (Sweden)

    Jun-Qin Wang

    Full Text Available To identify differentially expressed genes associated with motion sickness (MS susceptibility in the rat caudal vestibular nucleus.We identified MS susceptible (MSS and insusceptible (inMSS rats by quantifying rotation-induced MS symptoms: defecation and spontaneous locomotion activity. Microarray analysis was used to screen differentially expressed genes in the caudal vestibular nucleus (CVN after rotation. Plasma stress hormones were identified by radioimmunoassay. Candidate genes were selected by bioinformatics analysis and the microarray results were verified by real-time quantitative-PCR (RT-qPCR methods. By using Elvax implantation, receptor antagonists or recombinant adenovirus targeting the candidate genes were applied to the CVN to evaluate their contribution to MS susceptibility variability. Validity of gene expression manipulation was verified by RT-qPCR and western blot analysis.A total of 304 transcripts were differentially expressed in the MSS group compared with the inMSS group. RT-qPCR analysis verified the expression pattern of candidate genes, including nicotinic cholinergic receptor (nAchR α3 subunit, 5-hydroxytryptamine receptor 4 (5-HT4R, tachykinin neurokinin-1 (NK1R, γ-aminobutyric acid A receptor (GABAAR α6 subunit, olfactory receptor 81 (Olr81 and homology 2 domain-containing transforming protein 1 (Shc1. In MSS animals, the nAchR antagonist mecamylamine significantly alleviated rotation-induced MS symptoms and the plasma β-endorphin response. The NK1R antagonist CP99994 and Olr81 knock-down were effective for the defecation response, while the 5-HT4R antagonist RS39604 and Shc1 over-expression showed no therapeutic effect. In inMSS animals, rotation-induced changes in spontaneous locomotion activity and the plasma β-endorphin level occurred in the presence of the GABAAR antagonist gabazine.Our findings suggested that the variability of the CVN gene expression profile after motion stimulation might be a putative

  4. Investigation of strong motion processing procedures

    International Nuclear Information System (INIS)

    Rinaldi, D.; Goula, X.; Menu, J.M.

    1988-03-01

    The work which is described here presents preliminary results of an on-going research relating to the accurate recording and quality processing of earthquake strong ground motions. The work is the product of a tripartite co-operation between three European Centres (ENEA, PAS-ISP Laboratorio Ingengneria dei Siti, Rome/CEA, IPSN, Fontenay-aux-Roses, ICST, Department of Civil Engineering, London), which have carried out independently similar research in the recent past. Other European Institutes joined the three mentioned organizations for discussions during a Workshop (June 1985) held in Casaccia (ENEA Research Centre of Rome). The aim of the research is a thorough analysis of various factors affecting the recovery of true ground accelerations recorded with analogue instruments. The separate and cumulative effects of the type of recording accelerometer, the digitization equipment and the correction routines have been analysed. Global comparisons have been achieved to obtain a general insight into various standard processing procedures

  5. Brain Activation by H1 Antihistamines Challenges Conventional View of Their Mechanism of Action in Motion Sickness: A Behavioral, c-Fos and Physiological Study in Suncus murinus (House Musk Shrew

    Directory of Open Access Journals (Sweden)

    Longlong Tu

    2017-06-01

    Full Text Available Motion sickness occurs under a variety of circumstances and is common in the general population. It is usually associated with changes in gastric motility, and hypothermia, which are argued to be surrogate markers for nausea; there are also reports that respiratory function is affected. As laboratory rodents are incapable of vomiting, Suncus murinus was used to model motion sickness and to investigate changes in gastric myoelectric activity (GMA and temperature homeostasis using radiotelemetry, whilst also simultaneously investigating changes in respiratory function using whole body plethysmography. The anti-emetic potential of the highly selective histamine H1 receptor antagonists, mepyramine (brain penetrant, and cetirizine (non-brain penetrant, along with the muscarinic receptor antagonist, scopolamine, were investigated in the present study. On isolated ileal segments from Suncus murinus, both mepyramine and cetirizine non-competitively antagonized the contractile action of histamine with pKb values of 7.5 and 8.4, respectively; scopolamine competitively antagonized the contractile action of acetylcholine with pA2 of 9.5. In responding animals, motion (1 Hz, 4 cm horizontal displacement, 10 min increased the percentage of the power of bradygastria, and decreased the percentage power of normogastria whilst also causing hypothermia. Animals also exhibited an increase in respiratory rate and a reduction in tidal volume. Mepyramine (50 mg/kg, i.p. and scopolamine (10 mg/kg, i.p., but not cetirizine (10 mg/kg, i.p., significantly antagonized motion-induced emesis but did not reverse the motion-induced disruptions of GMA, or hypothermia, or effects on respiration. Burst analysis of plethysmographic-derived waveforms showed mepyramine also had increased the inter-retch+vomit frequency, and emetic episode duration. Immunohistochemistry demonstrated that motion alone did not induce c-fos expression in the brain. Paradoxically, mepyramine increased c

  6. Health anxiety in a disease-avoidance framework: Investigation of anxiety, disgust and disease perception in response to sickness cues.

    Science.gov (United States)

    Hedman, Erik; Lekander, Mats; Karshikoff, Bianka; Ljótsson, Brjánn; Axelsson, Erland; Axelsson, John

    2016-10-01

    Severe health anxiety is characterized by a debilitating fear of somatic illness, and avoidance of disease-related stimuli plays a key role in the maintenance of the disorder. The aim of this study was to investigate severe health anxiety within an evolutionary disease-avoidance framework. We hypothesized that, compared to healthy controls, participants with severe health anxiety would perceive others as sicker, more contagious, and less attractive. We also expected individuals with severe health anxiety to be more prone to avoid interaction with persons who appeared sick, as well as to respond with more health-related worry, more disgust, and more anxiety when confronting such individuals. In addition, this sensitivity was expected to be larger if people showed manifest sickness symptoms. Participants with and without severe health anxiety (N = 224) were exposed to facial photos with a varying degree of apparent sickness. Patients with severe health anxiety, compared to controls, rated apparently healthy people as being less healthy and less attractive. There were significant interaction effects showing that that the increase in disgust, anxiety, perceived contagiousness, and worry over one's own health as a function of how sick the person in the photo appeared, was significantly larger in the clinical sample compared to the healthy control sample (ps anxiety as a dimensional predictor also supported our hypotheses. We suggest that disgust and cognitive biases relating to the disease-avoidance model are significant features of severe health anxiety. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  7. Investigation of Student Reasoning about Harmonic Motions

    Science.gov (United States)

    Tongnopparat, N.; Poonyawatpornkul, J.; Wattanakasiwich, P.

    This study aimed to investigate student reasoning about harmonic oscillations. We conducted a semi-structured interview based on three situations of harmonic motions—(1) a mass attaching to spring and horizontally oscillating without damping, (2) the same situation but vertically oscillating and (3) a mass attaching to spring and oscillating in viscous liquid. Forty-five second-year students taking a vibrations and wave course at Chiang Mai University, Thailand participated in a fifteen-minute interview, which was video-recorded. The videos were transcribed and analyzed by three physics instructors. As results, we found that most students had misconceptions about angular frequency and energy mostly in the second and third situations.

  8. Pathmorphological investigation of pulmonary infections complications in persons dying from acute radiation sickness after Chernobyl accident

    International Nuclear Information System (INIS)

    Vlasov, P.A.; Kvacheva, Yu.E.

    1993-01-01

    Lungs of 27 persons who participated in liquidation of Chernobyl accident and died from acute radiation sickness were studied histologically. Pulmonary infections were found, including invasion of viral, bacterial and fungal agents. Being depended on hematopoietic function the inflammatory reactions were areactive during postirradiation aplasia and became typical within the recovery beginning

  9. Human otolith-ocular reflexes during off-vertical axis rotation: effect of frequency on tilt-translation ambiguity and motion sickness

    Science.gov (United States)

    Wood, Scott J.; Paloski, W. H. (Principal Investigator)

    2002-01-01

    The purpose of this study was to examine how the modulation of tilt and translation otolith-ocular responses during constant velocity off-vertical axis rotation varies as a function of stimulus frequency. Eighteen human subjects were rotated in darkness about their longitudinal axis 30 degrees off-vertical at stimulus frequencies between 0.05 and 0.8 Hz. The modulation of torsion decreased while the modulation of horizontal slow phase velocity (SPV) increased with increasing frequency. It is inferred that the ambiguity of otolith afferent information is greatest in the frequency region where tilt (torsion) and translational (horizontal SPV) otolith-ocular responses crossover. It is postulated that the previously demonstrated peak in motion sickness susceptibility during linear accelerations around 0.3 Hz is the result of frequency segregation of ambiguous otolith information being inadequate to distinguish between tilt and translation.

  10. Car Sickness

    Science.gov (United States)

    ... Preventable Diseases Healthy Children > Health Issues > Conditions > Head Neck & Nervous System > Car Sickness Health Issues Listen Español Text Size Email Print Share Car Sickness Page Content ...

  11. Investigation of the circular random walk motion in nematic material

    International Nuclear Information System (INIS)

    Bata, L.; Tuettoe, I.

    1976-12-01

    The molecular dynamics of liquid crystalline mesophase is investigated. A new theoretical model describing the rotational motion on a sphere with two relaxation times is worked out. Quasi-elastic neutron spectra have been measured on aligned di-butyl derivative of phenylbenzoyl azoxy-benzoate at different temperatures. The results are interpreted on the basis of the author's model and the non-equivalence of the hydrogen atom is shown. (Sz.N.Z.)

  12. Investigation of possibilities for appearance of African horse sickness virus and changes in species of the genus "Culicoides" in Bulgaria

    Directory of Open Access Journals (Sweden)

    Chenchev I.

    2003-01-01

    Full Text Available To date, Bulgaria has been free of African Horse Sickness (AHS. Contacts with and proximity to countries, in which it is assumed there are cases of the disease, necessitate surveillance of equine animals near the border strict control of outgoing and incoming animals, especially those returning to the country after a long stay abroad of participation in races. Instructions for carrying out veterinary activities in instances when the disease occurs in Bulgaria have been worked out, since there were occurrences of Blue tongue disease (the disease has the same epizootiological vectors of spreading in regions bordering with Turkey last year. The serological screening investigations of blood sera by ELISA of equine animals from the same villages and regions during one active period of flight of culicoides did not establish the presence of antibodies to this dangerous transmissive disease. The present study contributed to working out scientific-methodological diagnostic preparedness in Bulgaria as regards this exotic transmassive disease.

  13. Digital anthropomorphic phantoms of non-rigid human respiratory and voluntary body motion for investigating motion correction in emission imaging

    International Nuclear Information System (INIS)

    Könik, Arda; Johnson, Karen L; Dasari, Paul; Pretorius, P H; Dey, Joyoni; King, Michael A; Connolly, Caitlin M; Segars, Paul W; Lindsay, Clifford

    2014-01-01

    and body motion phantoms with a varying extent and character for each individual. In addition to these phantoms, we recorded the position of markers placed on the chest of the volunteers for the body motion studies, which could be used as external motion measurement. Using these phantoms and external motion data, investigators will be able to test their motion correction approaches for realistic motion obtained from different individuals. The non-uniform rational B-spline data and the parameter files for these phantoms are freely available for downloading and can be used with the XCAT license. (paper)

  14. Digital anthropomorphic phantoms of non-rigid human respiratory and voluntary body motion for investigating motion correction in emission imaging

    Science.gov (United States)

    Könik, Arda; Connolly, Caitlin M.; Johnson, Karen L.; Dasari, Paul; Segars, Paul W.; Pretorius, P. H.; Lindsay, Clifford; Dey, Joyoni; King, Michael A.

    2014-07-01

    and body motion phantoms with a varying extent and character for each individual. In addition to these phantoms, we recorded the position of markers placed on the chest of the volunteers for the body motion studies, which could be used as external motion measurement. Using these phantoms and external motion data, investigators will be able to test their motion correction approaches for realistic motion obtained from different individuals. The non-uniform rational B-spline data and the parameter files for these phantoms are freely available for downloading and can be used with the XCAT license.

  15. Serum sickness

    Science.gov (United States)

    ... the problem should be stopped. Avoid using that medicine or antiserum in the future. ... Call your provider if you received medicine or antiserum in the last 4 weeks and have symptoms of serum sickness.

  16. Morning sickness

    Science.gov (United States)

    ... not predict how you will feel in future pregnancies. Causes The exact cause of morning sickness is unknown. It may be caused by hormone changes or lower blood sugar during early pregnancy. Emotional stress, fatigue, traveling, or some foods can ...

  17. Radiation sickness

    International Nuclear Information System (INIS)

    Endoh, Masaru; Ishida, Yusei; Saeki, Mitsuaki

    1983-01-01

    The frequency of radiation sickness in 1,060 patients treated at our Department was 12.8 percent. It was frequent in patients with brain cancer (12 percent), whole spine cancer (47 percent), uterus cancer (28 percent), lung cancer (22 percent) and esophagus cancer (12 percent). Radiation sickness following X-irradiation was studied in its relation to patient's age, size of radiation fields, dosis and white blood cell count. However, we could not find any definite clinical feature relevant to occurrence. There are many theories published concerning the mechanism of radiation sickness. Clinical experiences have shown that radiation sickness cannot be explained by one theory alone but by several theories such as those based on psychology, stress or histamine. (author)

  18. Cinerama sickness and postural instability.

    Science.gov (United States)

    Bos, Jelte E; Ledegang, Wietse D; Lubeck, Astrid J A; Stins, John F

    2013-01-01

    Motion sickness symptoms and increased postural instability induced by motion pictures have been reported in a laboratory, but not in a real cinema. We, therefore, carried out an observational study recording sickness severity and postural instability in 19 subjects before, immediately and 45 min after watching a 1 h 3D aviation documentary in a cinema. Sickness was significantly larger right after the movie than before, and in a lesser extent still so after 45 min. The average standard deviation of the lateral centre of pressure excursions was significantly larger only right afterwards. When low-pass filtered at 0.1 Hz, lateral and for-aft excursions were both significantly larger right after the movie, while for-aft excursions then remained larger even after 45 min. Speculating on previous findings, we predict more sickness and postural instability in 3D than in 2D movies, also suggesting a possible, but yet unknown risk for work-related activities and vehicle operation. Watching motion pictures may be sickening and posturally destabilising, but effects in a cinema are unknown. We, therefore, carried out an observational study showing that sickness then is mainly an issue during the exposure while postural instability is an issue afterwards.

  19. Sick building syndrome

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2002-06-01

    Full Text Available Sick building syndrome describes a number of mostly unspesific complaints of some occupants of the building. The exact pathophysiological mechanism remains elusive. It is a multi factorial event which may include physical, chemical, biological as well as psycological factors. In many cases it is due to insufficient maintenance of the HVAC (heating, ventilation, air conditioning system in the building. Sign and symptoms can be uncomfortable and even disabling, which may include mucus membrane irritation, neurotoxic symptoms, asthma like symptoms, skin complaints, gastrointestinal symptoms and other related symptoms. There are various investigation methods to diagnose sick building syndrome, and on site assessment of the building is extremely useful. Prevention through a proactive air quality monitoring program is far more desirable than dealing with an actual sick building. Indoor air and the sick building symdrome serves as a paradigm of modern occupational and environmental medicine. (Med J Indones 2002; 11:124-31Keywords: indoor air pollution, sick building syndrome, building related illness

  20. Sickness presence, sick leave and adjustment latitude

    Directory of Open Access Journals (Sweden)

    Joachim Gerich

    2014-10-01

    Full Text Available Objectives: Previous research on the association between adjustment latitude (defined as the opportunity to adjust work efforts in case of illness and sickness absence and sickness presence has produced inconsistent results. In particular, low adjustment latitude has been identified as both a risk factor and a deterrent of sick leave. The present study uses an alternative analytical strategy with the aim of joining these results together. Material and Methods: Using a cross-sectional design, a random sample of employees covered by the Upper Austrian Sickness Fund (N = 930 was analyzed. Logistic and ordinary least square (OLS regression models were used to examine the association between adjustment latitude and days of sickness absence, sickness presence, and an estimator for the individual sickness absence and sickness presence propensity. Results: A high level of adjustment latitude was found to be associated with a reduced number of days of sickness absence and sickness presence, but an elevated propensity for sickness absence. Conclusions: Employees with high adjustment latitude experience fewer days of health complaints associated with lower rates of sick leave and sickness presence compared to those with low adjustment latitude. In case of illness, however, high adjustment latitude is associated with a higher pro­bability of taking sick leave rather than sickness presence.

  1. Radiation sickness

    International Nuclear Information System (INIS)

    Chin, A.; Leer, J.W.H.; Craandijk, M.; Feenstra, W.F.F.

    1990-01-01

    In a prospective inventory analysis of 169 irradiated patients concerning the incidence and course of Acute Radiation Sickness (fatigue, loss of appetite, nausea and vomiting), it was found that 2/3 of the patients had these complaints. The complaints started during the first week of treatment and mostly even within a few hours after each radiotherapy session. All complaints were progressive during the radiotherapy course, but disappeared spontaneously within one week after completion of the treatment. The possible occurrence of these symptoms soon after the start of radiotherapy should be kept in mind, especially since they can be reduced by simple retimens. (author). 14 refs.; 2 tabs

  2. Investigating the Feasibility of Rapid MRI for Image-Guided Motion Management in Lung Cancer Radiotherapy

    Directory of Open Access Journals (Sweden)

    Amit Sawant

    2014-01-01

    Full Text Available Cycle-to-cycle variations in respiratory motion can cause significant geometric and dosimetric errors in the administration of lung cancer radiation therapy. A common limitation of the current strategies for motion management is that they assume a constant, reproducible respiratory cycle. In this work, we investigate the feasibility of using rapid MRI for providing long-term imaging of the thorax in order to better capture cycle-to-cycle variations. Two nonsmall-cell lung cancer patients were imaged (free-breathing, no extrinsic contrast, and 1.5 T scanner. A balanced steady-state-free-precession (b-SSFP sequence was used to acquire cine-2D and cine-3D (4D images. In the case of Patient 1 (right midlobe lesion, ~40 mm diameter, tumor motion was well correlated with diaphragmatic motion. In the case of Patient 2, (left upper-lobe lesion, ~60 mm diameter, tumor motion was poorly correlated with diaphragmatic motion. Furthermore, the motion of the tumor centroid was poorly correlated with the motion of individual points on the tumor boundary, indicating significant rotation and/or deformation. These studies indicate that image quality and acquisition speed of cine-2D MRI were adequate for motion monitoring. However, significant improvements are required to achieve comparable speeds for truly 4D MRI. Despite several challenges, rapid MRI offers a feasible and attractive tool for noninvasive, long-term motion monitoring.

  3. Investigating the feasibility of rapid MRI for image-guided motion management in lung cancer radiotherapy.

    Science.gov (United States)

    Sawant, Amit; Keall, Paul; Pauly, Kim Butts; Alley, Marcus; Vasanawala, Shreyas; Loo, Billy W; Hinkle, Jacob; Joshi, Sarang

    2014-01-01

    Cycle-to-cycle variations in respiratory motion can cause significant geometric and dosimetric errors in the administration of lung cancer radiation therapy. A common limitation of the current strategies for motion management is that they assume a constant, reproducible respiratory cycle. In this work, we investigate the feasibility of using rapid MRI for providing long-term imaging of the thorax in order to better capture cycle-to-cycle variations. Two nonsmall-cell lung cancer patients were imaged (free-breathing, no extrinsic contrast, and 1.5 T scanner). A balanced steady-state-free-precession (b-SSFP) sequence was used to acquire cine-2D and cine-3D (4D) images. In the case of Patient 1 (right midlobe lesion, ~40 mm diameter), tumor motion was well correlated with diaphragmatic motion. In the case of Patient 2, (left upper-lobe lesion, ~60 mm diameter), tumor motion was poorly correlated with diaphragmatic motion. Furthermore, the motion of the tumor centroid was poorly correlated with the motion of individual points on the tumor boundary, indicating significant rotation and/or deformation. These studies indicate that image quality and acquisition speed of cine-2D MRI were adequate for motion monitoring. However, significant improvements are required to achieve comparable speeds for truly 4D MRI. Despite several challenges, rapid MRI offers a feasible and attractive tool for noninvasive, long-term motion monitoring.

  4. Development and Experimental Investigations of Motion Detection Module for Smart Lighting System

    OpenAIRE

    Matveev, I.; Siemens, E.; Yurchenko, Aleksey Vasilievich; Kuznetsov, D.

    2016-01-01

    This work considers motion sensors as parts of the smart lighting system on basis of Beaglebone microcomputer. Detection system is designed for the smart lighting system. Experimental investigations of the detection system were made with different motion sensors. Based on the results comparative analysis was performed and optimal conditions for the detection system operation were found.

  5. Numerical and experimental investigations of human swimming motions.

    Science.gov (United States)

    Takagi, Hideki; Nakashima, Motomu; Sato, Yohei; Matsuuchi, Kazuo; Sanders, Ross H

    2016-08-01

    This paper reviews unsteady flow conditions in human swimming and identifies the limitations and future potential of the current methods of analysing unsteady flow. The capability of computational fluid dynamics (CFD) has been extended from approaches assuming steady-state conditions to consideration of unsteady/transient conditions associated with the body motion of a swimmer. However, to predict hydrodynamic forces and the swimmer's potential speeds accurately, more robust and efficient numerical methods are necessary, coupled with validation procedures, requiring detailed experimental data reflecting local flow. Experimental data obtained by particle image velocimetry (PIV) in this area are limited, because at present observations are restricted to a two-dimensional 1.0 m(2) area, though this could be improved if the output range of the associated laser sheet increased. Simulations of human swimming are expected to improve competitive swimming, and our review has identified two important advances relating to understanding the flow conditions affecting performance in front crawl swimming: one is a mechanism for generating unsteady fluid forces, and the other is a theory relating to increased speed and efficiency.

  6. Investigation of the Linker Swing Motion in the Zeolitic Imidazolate Framework ZIF-90

    KAUST Repository

    Zheng, Bin; Fu, Fang; Wang, Lian Li; Yang, Limin; Zhu, Yihan; Du, Huiling

    2018-01-01

    The linker swing motion in the zeolitic imidazolate framework ZIF-90 is investigated by density functional theory (DFT) calculation, molecular dynamics (MD) and grand-canonical Monte Carlo (GCMC) simulations. The relation between the terminal

  7. Investigating the possible effect of electrode support structure on motion artifact in wearable bioelectric signal monitoring.

    Science.gov (United States)

    Cömert, Alper; Hyttinen, Jari

    2015-05-15

    With advances in technology and increasing demand, wearable biosignal monitoring is developing and new applications are emerging. One of the main challenges facing the widespread use of wearable monitoring systems is the motion artifact. The sources of the motion artifact lie in the skin-electrode interface. Reducing the motion and deformation at this interface should have positive effects on signal quality. In this study, we aim to investigate whether the structure supporting the electrode can be designed to reduce the motion artifact with the hypothesis that this can be achieved by stabilizing the skin deformations around the electrode. We compare four textile electrodes with different support structure designs: a soft padding larger than the electrode area, a soft padding larger than the electrode area with a novel skin deformation restricting design, a soft padding the same size as the electrode area, and a rigid support the same size as the electrode. With five subjects and two electrode locations placed over different kinds of tissue at various mounting forces, we simultaneously measured the motion artifact, a motion affected ECG, and the real-time skin-electrode impedance during the application of controlled motion to the electrodes. The design of the electrode support structure has an effect on the generated motion artifact; good design with a skin stabilizing structure makes the electrodes physically more motion artifact resilient, directly affecting signal quality. Increasing the applied mounting force shows a positive effect up to 1,000 gr applied force. The properties of tissue under the electrode are an important factor in the generation of the motion artifact and the functioning of the electrodes. The relationship of motion artifact amplitude to the electrode movement magnitude is seen to be linear for smaller movements. For larger movements, the increase of motion generated a disproportionally larger artifact. The motion artifact and the induced

  8. Investigation of the Linker Swing Motion in the Zeolitic Imidazolate Framework ZIF-90

    KAUST Repository

    Zheng, Bin

    2018-03-13

    The linker swing motion in the zeolitic imidazolate framework ZIF-90 is investigated by density functional theory (DFT) calculation, molecular dynamics (MD) and grand-canonical Monte Carlo (GCMC) simulations. The relation between the terminal aldehyde group rotation and the linker swing motion is revealed. The extremely high activation energy of the linker swing motion in ZIF-90 can be attributed to the asymmetric geometry and electron distribution of aldehyde groups. The change in the gate structure resulting from the linker rotation is used to understand the guest adsorption in ZIF-90. This study shows that it is possible to tune the linker swing motion and then the properties of ZIF-90 by manipulating the terminal group rotation. The results highlight the importance of considering the internal freedom effects to correctly describe the linker swing motion and the flexibility of metal-organic frameworks (MOFs).

  9. Experimental and numerical investigation of the roll motion behavior of a floating liquefied natural gas system

    Science.gov (United States)

    Zhao, WenHua; Yang, JianMin; Hu, ZhiQiang; Xiao, LongFei; Peng, Tao

    2013-03-01

    The present paper does an experimental and numerical investigation of the hydrodynamic interaction and the response of a single point turret-moored Floating Liquefied Natural Gas (FLNG) system, which is a new type of floating LNG (Liquid Natural Gas) platform that consists of a ship-type FPSO hull equipped with LNG storage tanks and liquefaction plants. In particular, this study focuses on the investigation of the roll response of FLNG hull in free-decay motions, white noise waves and also in irregular waves. Model tests of the FLNG system in 60%H filling condition excited by both white noise waves and irregular waves combined with steady wind and current have been carried out. Response Amplitude Operators (RAOs) and time histories of the responses are obtained for sway, roll and yaw motions. Obvious Low Frequency (LF) components of the roll motions are observed, which may be out of expectation. To facilitate the physical understanding of this phenomenon, we filter the roll motions at the period of 30 s into two parts: the Wave Frequency (WF) motions and the Low Frequency (LF) motions respectively. The results indicate that the LF motions are closely related to the sway and yaw motions. Possible reasons for the presence of the LF motions of roll have been discussed in detail, through the comparison with the sway and yaw motions. As for the numerical part, the simulation of the modeled case is conducted with the help of the software SESAM®. A good agreement between experiments and calculations is reported within the scope of trends. However, the numerical simulations should be further improved for the prediction of the FLNG system in the heading sea.

  10. Experimental investigation of irregular motion impact on 4D PET-based particle therapy monitoring

    International Nuclear Information System (INIS)

    Tian, Y; Stützer, K; Enghardt, W; Priegnitz, M; Helmbrecht, S; Fiedler, F; Bert, C

    2016-01-01

    Particle therapy positron emission tomography (PT-PET) is an in vivo and non-invasive imaging technique to monitor treatment delivery in particle therapy. The inevitable patient respiratory motion during irradiation causes artefacts and inaccurate activity distribution in PET images. Four-dimensional (4D) maximum likelihood expectation maximisation (4D MLEM) allows for a compensation of these effects, but has up to now been restricted to regular motion for PT-PET investigations. However, intra-fractional motion during treatment might differ from that during acquisition of the 4D-planning CT (e.g. amplitude variation, baseline drift) and therefore might induce inaccurate 4D PET reconstruction results. This study investigates the impact of different irregular analytical one-dimensional (1D) motion patterns on PT-PET imaging by means of experiments with a radioactive source and irradiated moving phantoms. Three sorting methods, namely phase sorting, equal amplitude sorting and event-based amplitude sorting, were applied to manage the PET list-mode data. The influence of these sorting methods on the motion compensating algorithm has been analysed. The event-based amplitude sorting showed a superior performance and it is applicable for irregular motions with  ⩽4 mm amplitude elongation and drift. For motion with 10 mm baseline drift, the normalised root mean square error was as high as 10.5% and a 10 mm range deviation was observed. (note)

  11. Investigating the influence of respiratory motion on the radiation induced bystander effect in modulated radiotherapy

    Science.gov (United States)

    Cole, Aidan J.; McGarry, Conor K.; Butterworth, Karl T.; McMahon, Stephen J.; Hounsell, Alan R.; Prise, Kevin M.; O'Sullivan, Joe M.

    2013-12-01

    Respiratory motion introduces complex spatio-temporal variations in the dosimetry of radiotherapy and may contribute towards uncertainties in radiotherapy planning. This study investigates the potential radiobiological implications occurring due to tumour motion in areas of geometric miss in lung cancer radiotherapy. A bespoke phantom and motor-driven platform to replicate respiratory motion and study the consequences on tumour cell survival in vitro was constructed. Human non-small-cell lung cancer cell lines H460 and H1299 were irradiated in modulated radiotherapy configurations in the presence and absence of respiratory motion. Clonogenic survival was calculated for irradiated and shielded regions. Direction of motion, replication of dosimetry by multi-leaf collimator (MLC) manipulation and oscillating lead shielding were investigated to confirm differences in cell survival. Respiratory motion was shown to significantly increase survival for out-of-field regions for H460/H1299 cell lines when compared with static irradiation (p < 0.001). Significantly higher survival was found in the in-field region for the H460 cell line (p < 0.030). Oscillating lead shielding also produced these significant differences. Respiratory motion and oscillatory delivery of radiation dose to human tumour cells has a significant impact on in- and out-of-field survival in the presence of non-uniform irradiation in this in vitro set-up. This may have important radiobiological consequences for modulated radiotherapy in lung cancer.

  12. Experimental investigation of irregular motion impact on 4D PET-based particle therapy monitoring

    Science.gov (United States)

    Tian, Y.; Stützer, K.; Enghardt, W.; Priegnitz, M.; Helmbrecht, S.; Bert, C.; Fiedler, F.

    2016-01-01

    Particle therapy positron emission tomography (PT-PET) is an in vivo and non-invasive imaging technique to monitor treatment delivery in particle therapy. The inevitable patient respiratory motion during irradiation causes artefacts and inaccurate activity distribution in PET images. Four-dimensional (4D) maximum likelihood expectation maximisation (4D MLEM) allows for a compensation of these effects, but has up to now been restricted to regular motion for PT-PET investigations. However, intra-fractional motion during treatment might differ from that during acquisition of the 4D-planning CT (e.g. amplitude variation, baseline drift) and therefore might induce inaccurate 4D PET reconstruction results. This study investigates the impact of different irregular analytical one-dimensional (1D) motion patterns on PT-PET imaging by means of experiments with a radioactive source and irradiated moving phantoms. Three sorting methods, namely phase sorting, equal amplitude sorting and event-based amplitude sorting, were applied to manage the PET list-mode data. The influence of these sorting methods on the motion compensating algorithm has been analysed. The event-based amplitude sorting showed a superior performance and it is applicable for irregular motions with  ⩽4 mm amplitude elongation and drift. For motion with 10 mm baseline drift, the normalised root mean square error was as high as 10.5% and a 10 mm range deviation was observed.

  13. Changes in sickness absenteeism following the introduction of a qualifying day for sickness benefit--findings from Sweden Post

    DEFF Research Database (Denmark)

    Voss, M; Floderus, B; Diderichsen, F

    2001-01-01

    AIMS: In 1993, a qualifying day without sickness benefit was introduced to the Swedish sickness benefit system. The aim of the present study is to investigate sickness absenteeism before and after the introduction of the qualifying day, in the light of conditions inside and outside working life....... METHODS: The study was based on 1,952 female and 2,229 male employees of Sweden Post. Sickness absence was measured by sickness incidence one year before and one year after the introduction of the qualifying day (sick-leave events/person days at risk). Information about explanatory factors was collected...

  14. Job demands, health perception and sickness absence

    NARCIS (Netherlands)

    Roelen, C.A.; Koopmans, P.C.; de Graaf, J.H.; van Zandbergen, J.W.; Groothoff, J.W.

    2007-01-01

    Background Investigation of the relations between job demands, health and sickness absence is required to design a strategy for the prevention of absence and disability. Aim To study the relationships between (physical and psychological) job demands, health perception and sickness absence. Methods

  15. Investigation of patient, tumour and treatment variables affecting residual motion for respiratory-gated radiotherapy

    International Nuclear Information System (INIS)

    George, R; Ramakrishnan, V; Siebers, J V; Chung, T D; Keall, P J

    2006-01-01

    Respiratory gating can reduce the apparent respiratory motion during imaging and treatment; however, residual motion within the gating window remains. Respiratory training can improve respiratory reproducibility and, therefore, the efficacy of respiratory-gated radiotherapy. This study was conducted to determine whether residual motion during respiratory gating is affected by patient, tumour or treatment characteristics. The specific aims of this study were to: (1) identify significant characteristics affecting residual motion, (2) investigate time trends of residual motion over a period of days (inter-session) and (3) investigate time trends of residual motion within the same day (intra-session). Twenty-four lung cancer patients were enrolled in an Institutional Review Board (IRB)-approved protocol. For approximately five sessions, 331 four-minute, respiratory motion traces were acquired with free breathing, audio instructions and audio-visual biofeedback for each patient. The residual motion was quantified by the standard deviation of the displacement within the gating window. The generalized linear model was used to obtain coefficients for each variable within the model and to evaluate the clinical and statistical significance. The statistical significance was determined by a p-value <0.05, while effect sizes of ≥0.1 cm (one standard deviation) were considered clinically significant. This data analysis was applied to patient, tumour and treatment variables. Inter- and intra-session variations were also investigated. The only variable that was significant for both inhale- and exhale-based gating was disease type. In addition, visual-training displacement, breathing type and Karnofsky performance status (KPS) values were significant for inhale-based gating, and dose-per-fraction was significant for exhale-based gating. Temporal respiratory variations within and between sessions were observed for individual patients. However inter- and intra-session analyses did

  16. Investigation of patient, tumour and treatment variables affecting residual motion for respiratory-gated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    George, R [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Ramakrishnan, V [Department of Biostatistics, Virginia Commonwealth University, Richmond, VA (United States); Siebers, J V [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Chung, T D [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Keall, P J [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States)

    2006-10-21

    Respiratory gating can reduce the apparent respiratory motion during imaging and treatment; however, residual motion within the gating window remains. Respiratory training can improve respiratory reproducibility and, therefore, the efficacy of respiratory-gated radiotherapy. This study was conducted to determine whether residual motion during respiratory gating is affected by patient, tumour or treatment characteristics. The specific aims of this study were to: (1) identify significant characteristics affecting residual motion, (2) investigate time trends of residual motion over a period of days (inter-session) and (3) investigate time trends of residual motion within the same day (intra-session). Twenty-four lung cancer patients were enrolled in an Institutional Review Board (IRB)-approved protocol. For approximately five sessions, 331 four-minute, respiratory motion traces were acquired with free breathing, audio instructions and audio-visual biofeedback for each patient. The residual motion was quantified by the standard deviation of the displacement within the gating window. The generalized linear model was used to obtain coefficients for each variable within the model and to evaluate the clinical and statistical significance. The statistical significance was determined by a p-value <0.05, while effect sizes of {>=}0.1 cm (one standard deviation) were considered clinically significant. This data analysis was applied to patient, tumour and treatment variables. Inter- and intra-session variations were also investigated. The only variable that was significant for both inhale- and exhale-based gating was disease type. In addition, visual-training displacement, breathing type and Karnofsky performance status (KPS) values were significant for inhale-based gating, and dose-per-fraction was significant for exhale-based gating. Temporal respiratory variations within and between sessions were observed for individual patients. However inter- and intra-session analyses did

  17. Healthy change processes - Relations with job insecurity, sickness absenteeism, sickness presenteeism and turnover intention

    OpenAIRE

    Bødal, Åshild

    2017-01-01

    The aim of this study was to investigate whether the presence of a healthy change process (HCPI) could predict negative outcomes that normally follow organisational change, such as qualitative job insecurity, total sickness (sickness absenteeism and -presenteesim) and turnover intention. It was hypothesised that negative relationships existed between a healthy change process and qualitative job insecurity, total sickness and turnover intention. In addition, it was believed that experienced st...

  18. Experimental investigation of natural convection in a core of a marine reactor in rolling motion

    International Nuclear Information System (INIS)

    Murata, Hiroyuki; Sawada, Ken-ichi; Kobayashi, Michiyuki

    2000-01-01

    A series of single-phase natural circulation experiments in a simulated marine reactor mounted on a rolling bed was performed and the average Nusselt number in the core was evaluated in order to investigate effects of the rolling motion on the heat transfer in the core. Heat transfer with an upright attitude is well correlated with the Rayleigh number and is slightly lower than El-Genk's correlation. Heat transfer in the core is not affected by the inclination angle because the inclination of the present experiment is not large enough to cause any remarkable changes in the flow pattern of the core. Heat transfer in the core is enhanced by the rolling motion which is thought to cause internal flow in the core. Heat transfer during the rolling motion is correlated with the Richardson number for rolling motion, Ri R , and is classified into three regimes: (1) region A (0.05 R ≤0.3) where heat transfer is dominated by the inertial force due to the rolling motion; (2) region B (0.3 R ≤2) where heat transfer is affected by the combined effect of the inertial force and natural convection; and (3) region C (Ri R >2) where heat transfer is affected only by the natural convection. (author)

  19. Experimental investigation of single small bubble motion in linear shear flow in water

    International Nuclear Information System (INIS)

    Li, Zhongchun; Zhao, Yang; Song, Xiaoming; Yu, Hongxing; Jiang, Shengyao; Ishii, Mamoru

    2016-01-01

    Highlights: • The bubble motion in simple linear shear flow was experimentally investigated. • The bubble trajectories, bubble velocity and drag and lift force were obtained using image process routine. • The bubble trajectory was coupled with a zigzag motion and incline path. • The lift force was kept negative and it decreased when bubble diameter and shear flow magnitude increased. - Abstract: The motion of small bubble in a simple shear flow in water was experimental studied. Stable shear flow with low turbulence level was achieved with curved screen and measured using LDV. The bubbles were captured by high speed camera and the captured images were processed with digital image routine. The bubble was released from a capillary tube. The instantaneous bubble position, bubble velocity and forces were obtained based on the captured parameters. The quasi-steady lift coefficient was determined by the linear fitting of the bubble trajectory of several cycles. The results indicated that the lateral migration was coupled with the zigzag motion of bubble in the present experiment. The bubble migrated to the left side and its quasi-steady lift coefficient was negative. Good repeatable results were observed by measurements of 18 bubbles. The bubble motion in shear flow in water was first experimental studied and negative lift force was observed in the present study condition. The lift coefficient decreased when shear stress magnitude or bubble diameter increased in the present experiment condition.

  20. The Impact of Motion Induced Interruptions on Cognitive Performance

    Science.gov (United States)

    2014-07-23

    found that even participants presenting with minor physiological effects of motion experienced a decline in multitasking performance. Further, Yu...literature has investigated the impact of task based interruptions such as being inter- rupted by a phone call or writing an email . In these...Engineers Journal. 102 (2) 65-72. Matsangas, P. (2013). The Effect of Mild Motion Sickness and Sopite Syndrome on Multitasking Cognitive Performance

  1. The sick-building syndrome; Das Sick-Building-Syndrom

    Energy Technology Data Exchange (ETDEWEB)

    Henne, A.; Neumann, H.F.; Winneke, G.

    1992-12-31

    The sick-building syndrome is characterized by the presence of general, non-specific symptoms (e.g., headache, tiredness, respiratory problems, eye trouble, vertigo, nausea, unspecific hypersensitivity) in association with a particular indoor ambience. It is clearly distinguishable from `building-related illness`, referring to a well-defined clinical syndrome due to staying in a building and for which a cause can, in general, be established. Disorders in the case of the sick-building syndrome are manifold and confirmed objectifiable results are hardly available so far. Yet there are some organ-related methods for the confirmation of findings concerning, for instance, the eyes, the skin and the area of the nose. The causes of the incidence of sick-building syndrome are more or less unclear. It is a multifactorial phenomenon involving physical, biological, chemical, individual-specific and psychological factors. Buildings where sick-building syndrome occurs typically exhibit certain properties. The European Community has already made proposals for the investigation of incriminated buildings. A systematic survey by questionnaire together with individual interviews plays an import part towards clarifying the syndrome. (orig./UWA) [Deutsch] Das Sick-Building-Syndrom beschreibt das Vorhandensein von allgemeinen, nicht spezifischen Symptomen (z.B. Kopfschmerzen, Muedigkeit, Atembeschwerden, Augenreizungen, Schwindelgefuehl, Uebelkeit, unspezifische Ueberempfindlichkeit), assoziiert mit einer besonderen Innenraumumgebung. Deutlich hiervon abzugrenzen ist die ``Building related illness``, bei der ein klinisch definiertes Krankheitsbild vorliegt, das durch den Aufenthalt im Gebaeude verursacht wird und fuer das im allgemeinen eine Ursache ermittelt werden kann. Das Beschwerdebild beim Sick-Building-Syndrom ist vielfaeltig, und gesicherte, objektivierbare Befunde liegen hierzu bisher kaum vor. Dennoch gibt es einige organbezogenen Methoden zur Befundabsicherung, z.B. fuer das

  2. A 4D dose computation method to investigate motion interplay effects in scanned ion beam prostate therapy

    International Nuclear Information System (INIS)

    Ammazzalorso, F; Jelen, U

    2014-01-01

    In particle therapy, the interplay between beam scanning and target motion during treatment delivery may result in dose deterioration. Interplay effects have been studied for targets exhibiting periodic respiratory motion, however, they are not well understood for irregular motion patterns, such as those exhibited by the prostate. In this note, we propose and validate a 4D dose computation method, which enables estimation of effective dose delivered to the prostate by scanning ion beams in presence of intrafraction motion, as well as facilitates investigation of various motion interplay countermeasures. (note)

  3. Worried sick? Sickness absence during organizational turmoil

    OpenAIRE

    Bratberg, Espen; Monstad, Karin

    2011-01-01

    Sickness absence has risen over the past years in Norway. An explanation put forward is that a tougher labour market represents a health hazard, while a competing hypothesis predicts that loss of job security works as a disciplinary device. In this analysis we aim to trace a causal impact of organizational turmoil or job insecurity on sickness absence, applying a difference-in-difference approach. Utilizing a negative financial shock that hit specific employers and workplaces, we find that...

  4. Investigation of the density wave oscillation in ocean motions with reduced order models

    International Nuclear Information System (INIS)

    Yan, B.H.; Li, R.

    2018-01-01

    Highlights: •The parameter about the degree of instability is defined. •The results are in satisfactory agreement with experimental results. •The effect of ocean motions on DWO is analyzed quantitatively. •The results are of good universality and generality. -- Abstract: The two phase flow instability is an important phenomenon in nuclear power and thermal systems. In the research and design of small modular reactor, the effect of ocean motions on the two phase flow instability should be evaluated. In this work, the density wave oscillation in a uniformly heated channel in ocean motions is investigated with reduced order model by transforming the partial differential equations to ordinary differential equations. This kind of frequency domain method is complementary to the time domain analysis with system codes, not as alternatives. The parameter about the degree of instability is defined for the quantitative analysis of two phase flow instability. The results are in satisfactory agreement with experimental results. The effect of ocean motions on density wave oscillation in a uniformly heated channel is analyzed quantitatively. The parametric study is also carried out.

  5. Experimental investigation of shaping disturbance observer design for motion control of precision mechatronic stages with resonances

    Science.gov (United States)

    Yang, Jin; Hu, Chuxiong; Zhu, Yu; Wang, Ze; Zhang, Ming

    2017-08-01

    In this paper, shaping disturbance observer (SDOB) is investigated for precision mechatronic stages with middle-frequency zero/pole type resonance to achieve good motion control performance in practical manufacturing situations. Compared with traditional standard disturbance observer (DOB), in SDOB a pole-zero cancellation based shaping filter is cascaded to the mechatronic stage plant to meet the challenge of motion control performance deterioration caused by actual resonance. Noting that pole-zero cancellation is inevitably imperfect and the controller may even consequently become unstable in practice, frequency domain stability analysis is conducted to find out how each parameter of the shaping filter affects the control stability. Moreover, the robust design criterion of the shaping filter, and the design procedure of SDOB, are both proposed to guide the actual design and facilitate practical implementation. The SDOB with the proposed design criterion is applied to a linear motor driven stage and a voice motor driven stage, respectively. Experimental results consistently validate the effectiveness nature of the proposed SDOB scheme in practical mechatronics motion applications. The proposed SDOB design actually could be an effective unit in the controller design for motion stages of mechanical manufacture equipments.

  6. Examining paid sickness absence by shift workers.

    Science.gov (United States)

    Catano, V M; Bissonnette, A B

    2014-06-01

    Shift workers are at greater risk than day workers with respect to psychological and physical health, yet little research has linked shift work to increased sickness absence. To investigate the relationship between shift work and sickness absence while controlling for organizational and individual characteristics and shift work attributes that have confounded previous research. The study used archive data collected from three national surveys in Canada, each involving over 20000 employees and 6000 private-sector firms in 14 different occupational groups. The employees reported the number of paid sickness absence days in the past 12 months. Data were analysed using both chi-squared statistics and hierarchical regressions. Contrary to previous research, shift workers took less paid sickness absence than day workers. There were no differences in the length of the sickness absence between both groups or in sickness absence taken by female and male workers whether working days or shifts. Only job tenure, the presence of a union in the workplace and working rotating shifts predicted sickness absence in shift workers. The results were consistent across all three samples. In general, shift work does not seem to be linked to increased sickness absence. However, such associations may be true for specific industries. Male and female workers did not differ in the amount of sickness absence taken. Rotating shifts, regardless of industry, predicted sickness absence among shift workers. Consideration should be given to implementing scheduled time off between shift changes. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Subjective assessment of acute mountain sickness: investigating the relationship between the Lake Louise Self-Report, a visual analogue scale and psychological well-being scales.

    Science.gov (United States)

    Frühauf, Anika; Burtscher, Martin; Pocecco, Elena; Faulhaber, Martin; Kopp, Martin

    2016-01-01

    There is an ongoing discussion how to assess acute mountain sickness (AMS) in real life conditions. Next to more-item scales with a cut off like the Lake Louise Self-Report (LLS), some authors suggested to use visual analog scales (VAS) to assess AMS. This study tried to contribute to this question using VAS items used for the Subjective Ratings of Drug Effects, including an additional single item for AMS. Furthermore, we investigated if instruments developed to assess psychological well-being might predict AMS assessed via LLS or VAS. 32 (19 Female) adult persons with known AMS susceptibility filled in questionnaires (Feeling Scale, Felt Arousal Scale, Activation Deactivation Check List, LLS, VAS) at a height of 3650 m above sea level. Correlation and regression analysis suggest a moderate to high relationship between the LLS score and the VAS items, including one VAS item asking for the severity of AMS, as well as psychological well-being. In conclusion, using VAS items to assess AMS can be a more precise alternative to questionnaires like LLS, for people knowledgeable with AMS. Furthermore, researchers should be aware that psychological well-being might be an important parameter influencing the assessment of AMS.

  8. Predictors of sickness absence in pregnancy

    DEFF Research Database (Denmark)

    Hansen, Mette Lausten; Thulstrup, Ane Marie; Juhl, Mette

    2014-01-01

    OBJECTIVE: The aim of this cohort study was to investigate associations between parity, pre-pregnancy body mass index (BMI), assisted reproductive therapy (ART), time to pregnancy (TTP), and engagement in physical exercise and the risk of sickness absence in pregnancy from 10-29 completed pregnancy...... with higher HR of sickness absence. Physical exercise of >120 minutes per week was associated with lower HR 0.84 (95% CI 0.75-0.95). CONCLUSION: Risk for sickness absence was higher among women who were multiparous, overweight, obese, received ART, and had prolonged TTP, and lower among women engaged...

  9. Analyses of Sickness Absence

    NARCIS (Netherlands)

    Heijnen, S.M.M.

    2014-01-01

    Sickness absence is an empirical phenomenon of all time. Generally, it has a medical cause. However, other factors also appear to have an impact on the actual rate of sickness absence, such as the institutional setting, the business cycle and the economic structure. Many questions on the different

  10. Presenteeism among sick workers

    NARCIS (Netherlands)

    Houtman, I.L.D.

    2003-01-01

    Much attention has been focused on absenteeism. However, ‘presenteeism’ is also an issue, i.e. staying at work even when feeling sick. Analyses have shown that, the greater the work pressure, the higher the percentage of people who keep working when feeling sick.

  11. A geophone wireless sensor network for investigating glacier stick-slip motion

    Science.gov (United States)

    Martinez, Kirk; Hart, Jane K.; Basford, Philip J.; Bragg, Graeme M.; Ward, Tyler; Young, David S.

    2017-08-01

    We have developed an innovative passive borehole geophone system, as part of a wireless environmental sensor network to investigate glacier stick-slip motion. The new geophone nodes use an ARM Cortex-M3 processor with a low power design capable of running on battery power while embedded in the ice. Only data from seismic events was stored, held temporarily on a micro-SD card until they were retrieved by systems on the glacier surface which are connected to the internet. The sampling rates, detection and filtering levels were determined from a field trial using a standard commercial passive seismic system. The new system was installed on the Skalafellsjökull glacier in Iceland and provided encouraging results. The results showed that there was a relationship between surface melt water production and seismic event (ice quakes), and these occurred on a pattern related to the glacier surface melt-water controlled velocity changes (stick-slip motion). Three types of seismic events were identified, which were interpreted to reflect a pattern of till deformation (Type A), basal sliding (Type B) and hydraulic transience (Type C) associated with stick-slip motion.

  12. Experimental Investigation of Unsteady Aerodynamic Forces on Airfoil in Harmonic Translatory Motion

    DEFF Research Database (Denmark)

    Gaunaa, Mac; Sørensen, Jens Nørkær

    2003-01-01

    The present paper describes the main results from an experimental investigation of the unsteady aerodynamic forces on a NACA 0015 airfoil subject to 1-degree-of-freedom (DOF) harmonic translatory motion. The focus of the experimental investigations was to determine the factors that influence...... maximum lift for both stationary and moving airfoil configurations. The mean as well as the dynamic characteristics of the different stall levels were found to differ from each other. An investigation of the negative aerodynamically damped cases showed that the damping decrease as the reduced frequency...... is decreased. Comparison between the experimental data, 2D Navier-Stokes computations and two commonly used dynamic stall models reveal that all models failed to reproduce the dynamic characteristics of the flow for incidences above maximum lift, however the Navier-Stokes computations generally captured...

  13. Experimental investigation of a supercritical airfoil boundary layer in pitching motion

    Energy Technology Data Exchange (ETDEWEB)

    Masdari, Mehran; Tabrizian, Arshia [Faculty of New Science and Technology, University of Tehran, Tehran (Iran, Islamic Republic of); Jahanmiri, Mohsen; Gorji, Mohamamd [Dept. of Mechanical and Aerospace Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of); Soltani, Mohammad Reza [Dept. of Aerospace Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of)

    2017-01-15

    In this study, the boundary layer velocity profile on the upper surface of a supercritical airfoil in a forced sinusoidal pitching motion was measured and experimentally investigated. Measurements were performed using a boundary layer rake, including total pressure tubes positioned at 25 % of the chord far from the leading edge on the upper surface. For static measurements, the effects of the angle of attack between −3° and 14° and free-stream velocity between 40 m/s and 70 m/s were investigated; for dynamic measurements, the effects of oscillation amplitude variation between ±3° and ±10°, reduced frequency from 0.007 to 0.0313, and mean angle of attack between −3° and 6° were studied during one oscillation cycle. Results indicated that the boundary layer thickness decreased in upstroke motion. Increasing the oscillation frequency led to the extension of hysteresis loops. Fast Fourier transform was used on pressure signals to study the amplitude of the dominant frequency in the velocity profile. Spectral analysis showed that the dominant forced frequency of oscillation in the boundary layer and the amplitude of this frequency were varied by increasing the reduced frequency and other parameters.

  14. Sick of Taxes?

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    I estimate a price elasticity of sickness absence. Sick leave is an intensive margin of labor supply where individuals are free to adjust. I exploit variation in tax rates over two decades, which provide thousands of differential incentives across time and space, to estimate the price responsiven...... of sick leave, -0.7, with respect to the net of tax rate. Though large relative to traditional labor supply elasticities, Swedes are half as price elastic as bike messengers, and just as elastic as stadium vendors on the margin which they can adjust freely....

  15. Investigating motion and stability of particles in flows using numerical models

    Science.gov (United States)

    Khurana, Nidhi

    The phenomenon of transport of particles in a fluid is ubiquitous in nature and a detailed understanding of its mechanism continues to remain a fundamental question for physicists. In this thesis, we use numerical methods to study the dynamics and stability of particles advected in flows. First, we investigate the dynamics of a single, motile particle advected in a two-dimensional chaotic flow. The particle can be either spherical or ellipsoidal. Particle activity is modeled as a constant intrinsic swimming velocity and stochastic fluctuations in both the translational and rotational motions are also taken into account. Our results indicate that interaction of swimming with flow structures causes a reduction in long-term transport at low speeds. Swimmers can get trapped at the transport barriers of the flow. We show that elongated swimmers respond more strongly to the dynamical structures of the flow field. At low speeds, their macroscopic transport is reduced even further than in the case of spherical swimmers. However, at high speeds these elongated swimmers tend to get attracted to the stable manifolds of hyperbolic fixed points, leading to increased transport. We then investigate the collective dynamics of a system of particles. The particles may interact both with each other and with the background flow. We focus on two different cases. In the fist case, we examine the stability of aggregation models in a turbulent-like flow. We use a simple aggregation model in which a point-like particle moves with a constant intrinsic speed while its velocity vector is reoriented according to the average direction of motion of its neighbors. We generate a strongly fluctuating, spatially correlated background flow using Kinematic Simulation, and show that flocks are highly sensitive to this background flow and break into smaller clusters. Our results indicate that such environmental perturbations must be taken into account for models which aim to capture the collective

  16. Sick but yet at work. An empirical study of sickness presenteeism.

    Science.gov (United States)

    Aronsson, G; Gustafsson, K; Dallner, M

    2000-07-01

    The study is an empirical investigation of sickness presenteeism in relation to occupation, irreplaceability, ill health, sickness absenteeism, personal income, and slimmed down organisation. Cross sectional design. Swedish workforce. The study group comprised a stratified subsample of 3801 employed persons working at the time of the survey, interviewed by telephone in conjunction with Statistics Sweden's labour market surveys of August and September 1997. The response rate was 87 per cent. A third of the persons in the total material reported that they had gone to work two or more times during the preceding year despite the feeling that, in the light of their perceived state of health, they should have taken sick leave. The highest presenteeism is largely to be found in the care and welfare and education sectors (nursing and midwifery professionals, registered nurses, nursing home aides, compulsory school teachers and preschool/primary educationalists. All these groups work in sectors that have faced personnel cutbacks during the 1990s). The risk ratio (odds ratio (OR)) for sickness presenteeism in the group that has to re-do work remaining after a period of absence through sickness is 2.29 (95% CI 1.79, 2.93). High proportions of persons with upper back/neck pain and fatigue/slightly depressed are among those with high presenteeism (pwork when sick. The link between difficulties in replacement or finding a stand in and sickness presenteeism is confirmed by study results. The categories with high sickness presenteeism experience symptoms more often than those without presenteeism. The most common combination is low monthly income, high sickness absenteeism and high sickness presenteeism.

  17. Theoretical and experimental investigation into structural and fluid motions at low frequencies in water distribution pipes

    Science.gov (United States)

    Gao, Yan; Liu, Yuyou

    2017-06-01

    Vibrational energy is transmitted in buried fluid-filled pipes in a variety of wave types. Axisymmetric (n = 0) waves are of practical interest in the application of acoustic techniques for the detection of leaks in underground pipelines. At low frequencies n = 0 waves propagate longitudinally as fluid-dominated (s = 1) and shell-dominated (s = 2) waves. Whilst sensors such as hydrophones and accelerometers are commonly used to detect leaks in water distribution pipes, the mechanism governing the structural and fluid motions is not well documented. In this paper, the low-frequency behaviour of the pipe wall and the contained fluid is investigated. For most practical pipework systems, these two waves are strongly coupled; in this circumstance the ratios of the radial pipe wall displacements along with the internal pressures associated with these two wave types are obtained. Numerical examples show the relative insensitivity of the structural and fluid motions to the s = 2 wave for both metallic and plastic pipes buried in two typical soils. It is also demonstrated that although both acoustic and vibration sensors at the same location provide the identical phase information of the transmitted signals, pressure responses have significantly higher levels than acceleration responses, and thus hydrophones are better suited in a low signal-to-noise ratio (SNR) environment. This is supported by experimental work carried out at a leak detection facility. Additional pressure measurements involved excitation of the fluid and the pipe fitting (hydrant) on a dedicated water pipe. This work demonstrates that the s = 1 wave is mainly responsible for the structural and fluid motions at low frequencies in water distribution pipes as a result of water leakage and direct pipe excitation.

  18. Experimental investigation on the motion of cathode spots in removing oxide film on metal surface by vacuum arc

    International Nuclear Information System (INIS)

    Shi Zongqian; Jia Shenli; Wang Lijun; Yuan Qingjun; Song Xiaochuan

    2008-01-01

    The motion of vacuum arc cathode spots has a very important influence on the efficiency of removing the oxide film on the metal surface. In this paper, the characteristics of cathode spot motion are investigated experimentally. Experiments were conducted in a detachable vacuum chamber with ac (50 Hz) arc current of 1 kA (rms). A stainless steel plate covered by an oxide layer was used as the cathode. The motion of cathode spots during the descaling process was photographed by a high-speed digital camera with an exposure time of 2 μs. Experimental results indicate that the motion of cathode spots is influenced by the interaction among individual cathode jets and the position of the anode as well as the surface condition. The waveform of arc voltage is also influenced by the motion of cathode spots

  19. Acute mountain sickness

    Science.gov (United States)

    ... GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Acute mountain sickness URL of this page: //medlineplus.gov/ency/article/ ...

  20. Investigation and Development of Control Laws for the NASA Langley Research Center Cockpit Motion Facility

    Science.gov (United States)

    Coon, Craig R.; Cardullo, Frank M.; Zaychik, Kirill B.

    2014-01-01

    The ability to develop highly advanced simulators is a critical need that has the ability to significantly impact the aerospace industry. The aerospace industry is advancing at an ever increasing pace and flight simulators must match this development with ever increasing urgency. In order to address both current problems and potential advancements with flight simulator techniques, several aspects of current control law technology of the National Aeronautics and Space Administration (NASA) Langley Research Center's Cockpit Motion Facility (CMF) motion base simulator were examined. Preliminary investigation of linear models based upon hardware data were examined to ensure that the most accurate models are used. This research identified both system improvements in the bandwidth and more reliable linear models. Advancements in the compensator design were developed and verified through multiple techniques. The position error rate feedback, the acceleration feedback and the force feedback were all analyzed in the heave direction using the nonlinear model of the hardware. Improvements were made using the position error rate feedback technique. The acceleration feedback compensator also provided noteworthy improvement, while attempts at implementing a force feedback compensator proved unsuccessful.

  1. Stud arc welding in a magnetic field – Investigation of the influences on the arc motion

    International Nuclear Information System (INIS)

    Hartz-Behrend, K; Forster, G; Schein, J; Marqués, J L; Jenicek, A; Müller, M; Cramer, H; Jilg, A; Soyer, H

    2014-01-01

    Stud arc welding is widely used in the construction industry. For welding of studs with a diameter larger than 14 mm a ceramic ferrule is usually necessary in order to protect the weld pool. Disadvantages of using such a ferrule are that more metal is molten than necessary for a high quality welded joint and that the ferrule is a consumable generally thrown away after the welding operation. Investigations show that the ferrule can be omitted when the welding is carried out in a radially symmetric magnetic field within a shielding gas atmosphere. Due to the Lorentz force the arc is laterally shifted so that a very uniform and controlled melting of the stud contact surface as well as of the work piece can be achieved. In this paper a simplified physical model is presented describing how the parameters welding current, flux density of the magnetic field, radius of the arc and mass density of the shielding gas influence the velocity of the arc motion. The resulting equation is subsequently verified by comparing it to optical measurements of the arc motion. The proposed model can be used to optimize the required field distribution for the magnetic field stud welding process

  2. Investigation of a Ball Screw Feed Drive System Based on Dynamic Modeling for Motion Control

    Directory of Open Access Journals (Sweden)

    Yi-Cheng Huang

    2017-06-01

    Full Text Available This paper examines the frequency response relationship between the ball screw nut preload, ball screw torsional stiffness variations and table mass effect for a single-axis feed drive system. Identification for the frequency response of an industrial ball screw drive system is very important for the precision motion when the vibration modes of the system are critical for controller design. In this study, there is translation and rotation modes of a ball screw feed drive system when positioning table is actuated by a servo motor. A lumped dynamic model to study the ball nut preload variation and torsional stiffness of the ball screw drive system is derived first. The mathematical modeling and numerical simulation provide the information of peak frequency response as the different levels of ball nut preload, ball screw torsional stiffness and table mass. The trend of increasing preload will indicate the abrupt peak change in frequency response spectrum analysis in some mode shapes. This study provides an approach to investigate the dynamic frequency response of a ball screw drive system, which provides significant information for better control performance when precise motion control is concerned.

  3. Phantom investigation of 3D motion-dependent volume aliasing during CT simulation for radiation therapy planning

    International Nuclear Information System (INIS)

    Tanyi, James A; Fuss, Martin; Varchena, Vladimir; Lancaster, Jack L; Salter, Bill J

    2007-01-01

    To quantify volumetric and positional aliasing during non-gated fast- and slow-scan acquisition CT in the presence of 3D target motion. Single-slice fast, single-slice slow, and multi-slice fast scan helical CTs were acquired of dynamic spherical targets (1 and 3.15 cm in diameter), embedded in an anthropomorphic phantom. 3D target motions typical of clinically observed tumor motion parameters were investigated. Motion excursions included ± 5, ± 10, and ± 15 mm displacements in the S-I direction synchronized with constant displacements of ± 5 and ± 2 mm in the A-P and lateral directions, respectively. For each target, scan technique, and motion excursion, eight different initial motion-to-scan phase relationships were investigated. An anticipated general trend of target volume overestimation was observed. The mean percentage overestimation of the true physical target volume typically increased with target motion amplitude and decreasing target diameter. Slow-scan percentage overestimations were larger, and better approximated the time-averaged motion envelope, as opposed to fast-scans. Motion induced centroid misrepresentation was greater in the S-I direction for fast-scan techniques, and transaxial direction for the slow-scan technique. Overestimation is fairly uniform for slice widths < 5 mm, beyond which there is gross overestimation. Non-gated CT imaging of targets describing clinically relevant, 3D motion results in aliased overestimation of the target volume and misrepresentation of centroid location, with little or no correlation between the physical target geometry and the CT-generated target geometry. Slow-scan techniques are a practical method for characterizing time-averaged target position. Fast-scan techniques provide a more reliable, albeit still distorted, target margin

  4. Using leap motion to investigate the emergence of structure in speech and language.

    Science.gov (United States)

    Eryilmaz, Kerem; Little, Hannah

    2017-10-01

     In evolutionary linguistics, experiments using artificial signal spaces are being used to investigate the emergenceof speech structure. These signal spaces need to be continuous, non-discretized spaces from which discrete unitsand patterns can emerge. They need to be dissimilar from-but comparable with-the vocal tract, in order tominimize interference from pre-existing linguistic knowledge, while informing us about language. This is a hardbalance to strike. This article outlines a new approach that uses the Leap Motion, an infrared controller that canconvert manual movement in 3d space into sound. The signal space using this approach is more flexible than signalspaces in previous attempts. Further, output data using this approach is simpler to arrange and analyze. Theexperimental interface was built using free, and mostly open- source libraries in Python. We provide our sourcecode for other researchers as open source.

  5. Space sickness on earth

    Science.gov (United States)

    Nooij, S. A. E.; Bos, J. E.; Groen, E. L.; Bles, W.; Ockels, W. J.

    2007-09-01

    During the first days in space, i.e., after a transition from 1G to 0G, more than 50% of the astro- (and cosmonauts) suffer from the Space Adaptation Syndrome (SAS).The symptoms of SAS, like nausea and dizziness, are especially provoked by head movements. Astronauts have mentioned close similarities between the symptoms of SAS and the symptoms they experienced after a 1 hour centrifuge run on Earth, i.e., after a transition from 3G to 1G (denoted by Sickness Induced by Centrifugation, SIC). During several space missions, we related susceptibility to SAS and to SIC in 11 astronauts and found 4 of them being susceptible to both SIC and SAS, and 7 being not susceptible to SIC nor to SAS. This correspondence in susceptibility suggests that SIC and SAS share the same underlying mechanism. To further study this mechanism, several vestibular parameters have been investigated (e.g. postural stability, vestibularly driven eye movements, subjective vertical). We found some striking changes in individual cases that are possibly due to the centrifuge run. However, the variability between subjects generally is very large, making physiological links to SIC and SAS still hard to find.

  6. Leadership styles of nurse managers and registered sickness absence among their nursing staff

    NARCIS (Netherlands)

    Schreuder, Jolanda A. H.; Roelen, Corne A. M.; van Zweeden, Nely F.; Jongsma, Dianne; van der Klink, Jac J. L.; Groothoff, Johan W.

    2011-01-01

    Background: Sickness absence leads to understaffing and interferes with nursing efficiency and quality. It has been reported in literature that managerial leadership is associated with self-reported sickness absence in the working population. Purposes: This study investigated the relationship

  7. Sleep disturbances and fatigue : independent predictors of sickness absence? A prospective study among 6538 employees

    NARCIS (Netherlands)

    Bultmann, Ute; Nielsen, Maj Britt D.; Madsen, Ida E. H.; Burr, Hermann; Rugulies, Reiner

    Background: Although sleep disturbances and fatigue are common conditions, frequently shown to be associated with sickness absence, only a few studies have prospectively investigated their independent effects on sickness absence, while adjusting for depressive symptoms. This study aims (i) to

  8. Gearbox Reliability Collaborative Investigation of Gearbox Motion and High-Speed-Shaft Loads

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Guo, Yi [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sethuraman, Latha [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-18

    This paper extends a model-to-test validation effort to examine the effect of different constant rotor torque and moment conditions and intentional generator misalignment on the gearbox motion and high-speed-shaft loads. Fully validating gearbox motion and high-speed-shaft loads across a range of test conditions is a critical precursor to examining the bearing loads, as the gearbox motion and high-speed-shaft loads are the drivers of these bearing loads.

  9. 19 CFR 210.60 - Designating an investigation “more complicated” for the purpose of adjudicating a motion for...

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Designating an investigation âmore complicatedâ for the purpose of adjudicating a motion for temporary relief. 210.60 Section 210.60 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE...

  10. SU-D-207A-05: Investigating Sparse-Sampled MRI for Motion Management in Thoracic Radiotherapy

    International Nuclear Information System (INIS)

    Sabouri, P; Sawant, A; Arai, T

    2016-01-01

    Purpose: Sparse sampling and reconstruction-based MRI techniques represent an attractive strategy to achieve sufficiently high image acquisition speed while maintaining image quality for the task of radiotherapy guidance. In this study, we examine rapid dynamic MRI using a sparse sampling sequence k-t BLAST in capturing motion-induced, cycle-to-cycle variations in tumor position. We investigate the utility of long-term MRI-based motion monitoring as a means of better characterizing respiration-induced tumor motion compared to a single-cycle 4DCT. Methods: An MRI-compatible, programmable, deformable lung motion phantom with eleven 1.5 ml water marker tubes was placed inside a 3.0 T whole-body MR scanner (Philips Ingenia). The phantom was programmed with 10 lung tumor motion traces previously recorded using the Synchrony system. 2D+t image sequences of a coronal slice were acquired using a balanced-SSFP sequence combined with k-t BLAST (accn=3, resolution=0.66×0.66×5 mm3; acquisition time = 110 ms/slice). kV fluoroscopic (ground truth) and 4DCT imaging was performed with the same phantom setup and motion trajectories. Marker positions in all three modalities were segmented and tracked using an opensource deformable image registration package, NiftyReg. Results: Marker trajectories obtained from rapid MRI exhibited <1 mm error compared to kv Fluoro trajectories in the presence of complex motion including baseline shifts and changes in respiratory amplitude, indicating the ability of MRI to monitor motion with adequate geometric fidelity for the purpose of radiotherapy guidance. In contrast, the trajectory derived from 4DCT exhibited significant errors up to 6 mm due to cycle-to-cycle variations and baseline shifts. Consequently, 4DCT was found to underestimate the range of marker motion by as much as 50%. Conclusion: Dynamic MRI is a promising tool for radiotherapy motion management as it permits for longterm, dose-free, soft-tissue-based monitoring of motion

  11. SU-D-207A-05: Investigating Sparse-Sampled MRI for Motion Management in Thoracic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Sabouri, P; Sawant, A [University of Maryland School of Medicine, Baltimore, MD (United States); Arai, T [University of Texas Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: Sparse sampling and reconstruction-based MRI techniques represent an attractive strategy to achieve sufficiently high image acquisition speed while maintaining image quality for the task of radiotherapy guidance. In this study, we examine rapid dynamic MRI using a sparse sampling sequence k-t BLAST in capturing motion-induced, cycle-to-cycle variations in tumor position. We investigate the utility of long-term MRI-based motion monitoring as a means of better characterizing respiration-induced tumor motion compared to a single-cycle 4DCT. Methods: An MRI-compatible, programmable, deformable lung motion phantom with eleven 1.5 ml water marker tubes was placed inside a 3.0 T whole-body MR scanner (Philips Ingenia). The phantom was programmed with 10 lung tumor motion traces previously recorded using the Synchrony system. 2D+t image sequences of a coronal slice were acquired using a balanced-SSFP sequence combined with k-t BLAST (accn=3, resolution=0.66×0.66×5 mm3; acquisition time = 110 ms/slice). kV fluoroscopic (ground truth) and 4DCT imaging was performed with the same phantom setup and motion trajectories. Marker positions in all three modalities were segmented and tracked using an opensource deformable image registration package, NiftyReg. Results: Marker trajectories obtained from rapid MRI exhibited <1 mm error compared to kv Fluoro trajectories in the presence of complex motion including baseline shifts and changes in respiratory amplitude, indicating the ability of MRI to monitor motion with adequate geometric fidelity for the purpose of radiotherapy guidance. In contrast, the trajectory derived from 4DCT exhibited significant errors up to 6 mm due to cycle-to-cycle variations and baseline shifts. Consequently, 4DCT was found to underestimate the range of marker motion by as much as 50%. Conclusion: Dynamic MRI is a promising tool for radiotherapy motion management as it permits for longterm, dose-free, soft-tissue-based monitoring of motion

  12. Return to work following sickness absence due to infectious mononucleosis

    NARCIS (Netherlands)

    Koopmans, P.C.; Bakhtali, R.; Katan, A.A.; Groothoff, J.W.; Roelen, C.A.

    BACKGROUND: Epstein-Barr virus infectious mononucleosis among adults is notorious because of the prolonged incapacitating fatigue it causes. AIMS: To investigate the duration of sickness absence and return to work following infectious mononucleosis. METHODS: Episodes of sickness absence due to

  13. Avoidable sickness absence in a dutch working population

    NARCIS (Netherlands)

    Kremer, A.M.; Steenbeek, R.

    2010-01-01

    Introduction Sickness absence has an important impact on employers (e.g. reduced productivity, high costs) and employees (e.g. replacement, job loss). Therefore, we investigated possible reduction by exploring avoidable sickness absence. Methods A questionnaire was filled out by 2,954 Dutch workers

  14. Sickness absence frequency among women working in hospital care

    NARCIS (Netherlands)

    Roelen, Corne A. M.; Schreuder, Jolanda A. H.; Koopmans, Petra C.; Moen, Bente E.; Groothoff, Johan W.

    2009-01-01

    Background Frequent short sickness absences result in understaffing and interfere with work processes. We need more knowledge about factors associated with this type of absence. Aims To investigate associations between the frequency of previous sickness absence and self-reported perceptions of

  15. Experimental investigation of a moving averaging algorithm for motion perpendicular to the leaf travel direction in dynamic MLC target tracking

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jai-Woong; Sawant, Amit; Suh, Yelin; Cho, Byung-Chul; Suh, Tae-Suk; Keall, Paul [Department of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul, Korea 131-700 and Research Institute of Biomedical Engineering, Catholic University of Korea, Seoul, 131-700 (Korea, Republic of); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States) and Department of Radiation Oncology, Asan Medical Center, Seoul, 138-736 (Korea, Republic of); Department of Biomedical Engineering, College of Medicine, Catholic University of Korea, Seoul, 131-700 and Research Institute of Biomedical Engineering, Catholic University of Korea, Seoul, 131-700 (Korea, Republic of); Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States) and Radiation Physics Laboratory, Sydney Medical School, University of Sydney, 2006 (Australia)

    2011-07-15

    Purpose: In dynamic multileaf collimator (MLC) motion tracking with complex intensity-modulated radiation therapy (IMRT) fields, target motion perpendicular to the MLC leaf travel direction can cause beam holds, which increase beam delivery time by up to a factor of 4. As a means to balance delivery efficiency and accuracy, a moving average algorithm was incorporated into a dynamic MLC motion tracking system (i.e., moving average tracking) to account for target motion perpendicular to the MLC leaf travel direction. The experimental investigation of the moving average algorithm compared with real-time tracking and no compensation beam delivery is described. Methods: The properties of the moving average algorithm were measured and compared with those of real-time tracking (dynamic MLC motion tracking accounting for both target motion parallel and perpendicular to the leaf travel direction) and no compensation beam delivery. The algorithm was investigated using a synthetic motion trace with a baseline drift and four patient-measured 3D tumor motion traces representing regular and irregular motions with varying baseline drifts. Each motion trace was reproduced by a moving platform. The delivery efficiency, geometric accuracy, and dosimetric accuracy were evaluated for conformal, step-and-shoot IMRT, and dynamic sliding window IMRT treatment plans using the synthetic and patient motion traces. The dosimetric accuracy was quantified via a {gamma}-test with a 3%/3 mm criterion. Results: The delivery efficiency ranged from 89 to 100% for moving average tracking, 26%-100% for real-time tracking, and 100% (by definition) for no compensation. The root-mean-square geometric error ranged from 3.2 to 4.0 mm for moving average tracking, 0.7-1.1 mm for real-time tracking, and 3.7-7.2 mm for no compensation. The percentage of dosimetric points failing the {gamma}-test ranged from 4 to 30% for moving average tracking, 0%-23% for real-time tracking, and 10%-47% for no compensation

  16. Experimental investigation of a moving averaging algorithm for motion perpendicular to the leaf travel direction in dynamic MLC target tracking.

    Science.gov (United States)

    Yoon, Jai-Woong; Sawant, Amit; Suh, Yelin; Cho, Byung-Chul; Suh, Tae-Suk; Keall, Paul

    2011-07-01

    In dynamic multileaf collimator (MLC) motion tracking with complex intensity-modulated radiation therapy (IMRT) fields, target motion perpendicular to the MLC leaf travel direction can cause beam holds, which increase beam delivery time by up to a factor of 4. As a means to balance delivery efficiency and accuracy, a moving average algorithm was incorporated into a dynamic MLC motion tracking system (i.e., moving average tracking) to account for target motion perpendicular to the MLC leaf travel direction. The experimental investigation of the moving average algorithm compared with real-time tracking and no compensation beam delivery is described. The properties of the moving average algorithm were measured and compared with those of real-time tracking (dynamic MLC motion tracking accounting for both target motion parallel and perpendicular to the leaf travel direction) and no compensation beam delivery. The algorithm was investigated using a synthetic motion trace with a baseline drift and four patient-measured 3D tumor motion traces representing regular and irregular motions with varying baseline drifts. Each motion trace was reproduced by a moving platform. The delivery efficiency, geometric accuracy, and dosimetric accuracy were evaluated for conformal, step-and-shoot IMRT, and dynamic sliding window IMRT treatment plans using the synthetic and patient motion traces. The dosimetric accuracy was quantified via a tgamma-test with a 3%/3 mm criterion. The delivery efficiency ranged from 89 to 100% for moving average tracking, 26%-100% for real-time tracking, and 100% (by definition) for no compensation. The root-mean-square geometric error ranged from 3.2 to 4.0 mm for moving average tracking, 0.7-1.1 mm for real-time tracking, and 3.7-7.2 mm for no compensation. The percentage of dosimetric points failing the gamma-test ranged from 4 to 30% for moving average tracking, 0%-23% for real-time tracking, and 10%-47% for no compensation. The delivery efficiency of

  17. Combining EEG, MIDI, and motion capture techniques for investigating musical performance.

    Science.gov (United States)

    Maidhof, Clemens; Kästner, Torsten; Makkonen, Tommi

    2014-03-01

    This article describes a setup for the simultaneous recording of electrophysiological data (EEG), musical data (MIDI), and three-dimensional movement data. Previously, each of these three different kinds of measurements, conducted sequentially, has been proven to provide important information about different aspects of music performance as an example of a demanding multisensory motor skill. With the method described here, it is possible to record brain-related activity and movement data simultaneously, with accurate timing resolution and at relatively low costs. EEG and MIDI data were synchronized with a modified version of the FTAP software, sending synchronization signals to the EEG recording device simultaneously with keypress events. Similarly, a motion capture system sent synchronization signals simultaneously with each recorded frame. The setup can be used for studies investigating cognitive and motor processes during music performance and music-like tasks--for example, in the domains of motor control, learning, music therapy, or musical emotions. Thus, this setup offers a promising possibility of a more behaviorally driven analysis of brain activity.

  18. Sick building syndrome

    International Nuclear Information System (INIS)

    Baechler, M.C.; Hadley, D.L.; Marseille, T.J.; Stenner, R.D.; Peterson, M.R.; Naugle, D.F.; Berry, M.A.

    1991-01-01

    This book discusses the aspect of indoor air pollution referred to as sick building syndrome. Covered are sources and health effects of various indoor air pollutants, and methods for mitigation of the problem, plus suggested analytical methods for environmental carcinogens found in indoor air

  19. Associations of work ability with frequent and long-term sickness absence

    NARCIS (Netherlands)

    Notenbomer, A.; Groothoff, J. W.; van Rhenen, W.; Roelen, C. A. M.

    Background Reduced work ability is related to long-term sickness absence. The relationship between work ability and frequent sickness absence has not previously been investigated. It is important to distinguish between frequent and long-term sickness absence as they are outcomes of different

  20. Occupational exposures and sick leave during pregnancy

    DEFF Research Database (Denmark)

    Hansen, Mette Lausten; Thulstrup, Ane Marie; Juhl, Mette

    2015-01-01

    OBJECTIVE: This study aimed to investigate associations between work postures, lifting at work, shift work, work hours, and job strain and the risk of sick leave during pregnancy from 10-29 completed pregnancy weeks in a large cohort of Danish pregnant women. METHODS: Data from 51 874 pregnancies...... in the Danish National Birth Cohort collected between 1996-2002 were linked to the Danish Register for Evaluation of Marginalization. Exposure information was based on telephone interviews. Hazard ratios (HR) with 95% confidence intervals (95% CI) were calculated by Cox regression analysis, using time of first...... episode of sick leave as the primary outcome. RESULTS: We found statistically significant associations between all the predictors and risk of sick leave; for non-sitting work postures (HRrange 1.55-2.79), cumulative lifting HRtrend 1.29, 95% CI 1.26-1.31, shift work (HRevening 1.90, 95% CI 1...

  1. Study of prochlorperazine (Stemetil) in radiation sickness

    International Nuclear Information System (INIS)

    Dutta, A.K.

    1976-01-01

    The incidence of radiation sickness and the efficacy of prochlorperazine in alleviating it among the patients under radiotherapy have been investigated. 116 patients from those under radiotherapy were randomly chosen. 38% of this sample developed radiation sickness symptoms (nausea and vomiting). The onset of symptoms occurred in the earlier periods of radiotherapy. The younger and older group were more susceptible to side effects of radiation. Prochlorperazine was administered immediately after the onset of symptoms of radiation sickness in the dose schedule of 10 mg twice daily for adults and was continued for 5 to 10 days after the alleviation of the symptoms. This was found to be effective in all patients. (M.G.B.)

  2. The prevalence of sick leave

    DEFF Research Database (Denmark)

    Backhausen, Mette; Damm, Peter; Bendix, Jane

    2018-01-01

    of long-term sick leave. Method Data from 508 employed pregnant women seeking antenatal care was collected by questionnaires from August 2015 to March 2016. The questionnaires, which were filled in at 20 and 32 weeks of gestation, provided information on maternal characteristics, the number of days spent...... on sick leave and the associated reasons. Descriptive statistics and logistic regression analysis were applied. Results The prevalence of sick leave was 56% of employed pregnant women in the first 32 weeks of gestation and more than one in four reported long-term sick leave (>20 days, continuous...... was a negative predictor. Conclusions The prevalence of sick leave was 56% in the first 32 weeks of gestation and more than one in four women reported long-term sick leave. The majority of reasons for sick leave were pregnancy-related and low back pain was the most frequently given reason....

  3. SU-E-J-135: An Investigation of Ultrasound Imaging for 3D Intra-Fraction Prostate Motion Estimation

    Energy Technology Data Exchange (ETDEWEB)

    O' Shea, T; Harris, E; Bamber, J [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, Greater London (United Kingdom); Evans, P [Centre for Vision, Speech and Signal Processing, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford (United Kingdom)

    2014-06-01

    Purpose: This study investigates the use of a mechanically swept 3D ultrasound (US) probe to estimate intra-fraction motion of the prostate during radiation therapy using an US phantom and simulated transperineal imaging. Methods: A 3D motion platform was used to translate an US speckle phantom while simulating transperineal US imaging. Motion patterns for five representative types of prostate motion, generated from patient data previously acquired with a Calypso system, were using to move the phantom in 3D. The phantom was also implanted with fiducial markers and subsequently tracked using the CyberKnife kV x-ray system for comparison. A normalised cross correlation block matching algorithm was used to track speckle patterns in 3D and 2D US data. Motion estimation results were compared with known phantom translations. Results: Transperineal 3D US could track superior-inferior (axial) and anterior-posterior (lateral) motion to better than 0.8 mm root-mean-square error (RMSE) at a volume rate of 1.7 Hz (comparable with kV x-ray tracking RMSE). Motion estimation accuracy was poorest along the US probe's swept axis (right-left; RL; RMSE < 4.2 mm) but simple regularisation methods could be used to improve RMSE (< 2 mm). 2D US was found to be feasible for slowly varying motion (RMSE < 0.5 mm). 3D US could also allow accurate radiation beam gating with displacement thresholds of 2 mm and 5 mm exhibiting a RMSE of less than 0.5 mm. Conclusion: 2D and 3D US speckle tracking is feasible for prostate motion estimation during radiation delivery. Since RL prostate motion is small in magnitude and frequency, 2D or a hybrid (2D/3D) US imaging approach which also accounts for potential prostate rotations could be used. Regularisation methods could be used to ensure the accuracy of tracking data, making US a feasible approach for gating or tracking in standard or hypo-fractionated prostate treatments.

  4. AN INVESTIGATION INTO THE CHARACTER OF PRE-EXPLOSION CORE-COLLAPSE SUPERNOVA SHOCK MOTION

    International Nuclear Information System (INIS)

    Burrows, Adam; Dolence, Joshua C.; Murphy, Jeremiah W.

    2012-01-01

    We investigate the structure of the stalled supernova shock in both two and three dimensions (2D and 3D, respectively) and explore the differences in the effects of neutrino heating and the standing accretion shock instability (SASI). We find that early on the amplitude of the dipolar mode of the shock is factors of ∼2-3 smaller in 3D than in 2D. However, later in both 3D and 2D, the monopole and dipole modes start to grow until explosion. Whereas in 2D, the (l, m) = (1, 0) mode changes sign quasi-periodically, producing the 'up-and-down' motion always seen in modern 2D simulations, in 3D this almost never happens. Rather, in 3D when the dipolar mode starts to grow, it grows in magnitude and wanders stochastically in direction until settling before explosion to a particular patch of solid angle. Furthermore, in 2D, we find that the amplitude of the dipolar shock deformation separates into two classes. For the first, identified with the SASI and for a wide range of 'low' neutrino luminosities, this amplitude remains small and roughly constant. For the other, identified with higher luminosities and neutrino-driven convection, the dipolar amplitude grows sharply. Importantly, it is only for this higher luminosity class that we see neutrino-driven explosions within ∼1 s of bounce. Moreover, for the 'low' luminosity runs (including zero), the power spectra of these dipolar oscillations peak in the 30-50 Hz range associated with advection timescales, while for the high-luminosity runs the power spectra at lower frequencies are significantly more prominent. We associate this enhanced power at lower frequencies with slower convective effects and the secular growth of the dipolar shock amplitude. Though our study involves a simplified, parameterized approach, on the basis of it we hypothesize that neutrino-driven buoyant convection should almost always dominate the SASI when the supernova explosion is neutrino-driven.

  5. Associations between partial sickness benefit and disability pensions: initial findings of a Finnish nationwide register study.

    Science.gov (United States)

    Kausto, Johanna; Virta, Lauri; Luukkonen, Ritva; Viikari-Juntura, Eira

    2010-06-23

    Timely return to work after longterm sickness absence and the increased use of flexible work arrangements together with partial health-related benefits are tools intended to increase participation in work life. Although partial sickness benefit and partial disability pension are used in many countries, prospective studies on their use are largely lacking. Partial sickness benefit was introduced in Finland in 2007. This register study aimed to investigate the use of health-related benefits by subjects with prolonged sickness absence, initially on either partial or full sick leave. Representative population data (13 375 men and 16 052 women either on partial or full sick leave in 2007) were drawn from national registers and followed over an average of 18 months. The registers provided information on the study outcomes: diagnoses and days of payment for compensated sick leaves, and the occurrence of disability pension. Survival analysis and multinomial regression were carried out using sociodemographic variables and prior sickness absence as covariates. Approximately 60% of subjects on partial sick leave and 30% of those on full sick leave had at least one recurrent sick leave over the follow up. A larger proportion of those on partial sick leave (16%) compared to those on full sick leave (1%) had their first recurrent sick leave during the first month of follow up. The adjusted risks of the first recurrent sick leave were 1.8 and 1.7 for men and women, respectively, when subjects on partial sick leave were compared with those on full sick leave. There was no increased risk when those with their first recurrent sick leave in the first month were excluded from the analyses. The risks of a full disability pension were smaller and risks of a partial disability pension approximately two-fold among men and women initially on partial sick leave, compared to subjects on full sick leave. This is the first follow up study of the newly adopted partial sickness benefit in

  6. Associations between partial sickness benefit and disability pensions: initial findings of a Finnish nationwide register study

    Directory of Open Access Journals (Sweden)

    Luukkonen Ritva

    2010-06-01

    Full Text Available Abstract Background Timely return to work after longterm sickness absence and the increased use of flexible work arrangements together with partial health-related benefits are tools intended to increase participation in work life. Although partial sickness benefit and partial disability pension are used in many countries, prospective studies on their use are largely lacking. Partial sickness benefit was introduced in Finland in 2007. This register study aimed to investigate the use of health-related benefits by subjects with prolonged sickness absence, initially on either partial or full sick leave. Methods Representative population data (13 375 men and 16 052 women either on partial or full sick leave in 2007 were drawn from national registers and followed over an average of 18 months. The registers provided information on the study outcomes: diagnoses and days of payment for compensated sick leaves, and the occurrence of disability pension. Survival analysis and multinomial regression were carried out using sociodemographic variables and prior sickness absence as covariates. Results Approximately 60% of subjects on partial sick leave and 30% of those on full sick leave had at least one recurrent sick leave over the follow up. A larger proportion of those on partial sick leave (16% compared to those on full sick leave (1% had their first recurrent sick leave during the first month of follow up. The adjusted risks of the first recurrent sick leave were 1.8 and 1.7 for men and women, respectively, when subjects on partial sick leave were compared with those on full sick leave. There was no increased risk when those with their first recurrent sick leave in the first month were excluded from the analyses. The risks of a full disability pension were smaller and risks of a partial disability pension approximately two-fold among men and women initially on partial sick leave, compared to subjects on full sick leave. Conclusions This is the first follow

  7. Investigation of the rolling motion of a hollow cylinder using a smartphone’s digital compass

    Science.gov (United States)

    Wattanayotin, Phattara; Puttharugsa, Chokchai; Khemmani, Supitch

    2017-07-01

    This study used a smartphone’s digital compass to observe the rolling motion of a hollow cylinder on an inclined plane. The smartphone (an iPhone 4s) was attached to the end of one side of a hollow cylinder to record the experimental data using the SensorLog application. In the experiment, the change of angular position was measured by the smartphone’s digital compass. The obtained results were then analyzed and calculated to determine various parameters of the motion, such as the angular velocity, angular acceleration, critical angle, and coefficient of static friction. The experimental results obtained from using the digital compass were compared with those obtained from using a gyroscope sensor. Moreover, the results obtained from both sensors were consistent with the calculations for the rolling motion. We expect that this experiment will be valuable for use in physics laboratories.

  8. Investigation of the effects of platform motion on the aerodynamics of a floating offshore wind turbine

    Institute of Scientific and Technical Information of China (English)

    万德成

    2016-01-01

    Along with the flourishing of the wind energy industry, floating offshore wind turbines have aroused much interest among the academia as well as enterprises. In this paper, the effects of the supporting platform motion on the aerodynamics of a floating wind turbine are studied using the open source CFD framework OpenFOAM. The platform motion responses, including surge, heave and pitch, are superimposed onto the rotation of the wind turbine. Thrust and torque on the wind turbine are compared and analysed for the cases of different platform motion patterns together with the flow field. It is shown that the movement of the supporting platform can have large influences on a floating offshore wind turbine and thus needs to be considered carefully during the design process.

  9. Job satisfaction and sickness absence: a questionnaire survey.

    Science.gov (United States)

    Roelen, Corné A M; Koopmans, Petra C; Notenbomer, Annette; Groothoff, Johan W

    2008-12-01

    When dissatisfaction with work precedes sickness absence, screening for satisfaction levels might usefully detect workers at risk of sickness absence. To investigate whether job satisfaction was associated with subsequent sickness absence days or episodes. A sample of workers was randomly drawn from a population of employees who had an episode of absence between January and April 2003. Job satisfaction was measured using a validated single question with a Likert-type scale ranging from 1 (very dissatisfied) to 7 (very satisfied). Job satisfaction levels were linked to the number of recorded sickness absence days and episodes in 2003, distinguishing between short (1-7 days) episodes and long (>7 days) episodes. Of 898 questionnaires distributed, 518 (58%) were returned. The mean+/-standard deviation job satisfaction level was 5.1+/-1.4 and negatively related to the number of sickness absence days. Job satisfaction was also negatively related to the number of short episodes and long episodes of absence, but these associations were not significant. Job satisfaction was significantly related to total sickness absence duration. The association with the number of sickness absence episodes was weak and just below the level of statistical significance. Assessing work satisfaction levels might usefully identify those workers most likely to have the greatest sickness absence duration.

  10. Focus Group Study Exploring Factors Related to Frequent Sickness Absence.

    Science.gov (United States)

    Notenbomer, Annette; Roelen, Corné A M; van Rhenen, Willem; Groothoff, Johan W

    2016-01-01

    Research investigating frequent sickness absence (3 or more episodes per year) is scarce and qualitative research from the perspective of frequent absentees themselves is lacking. The aim of the current study is to explore awareness, determinants of and solutions to frequent sickness absence from the perspective of frequent absentees themselves. We performed a qualitative study of 3 focus group discussions involving a total of 15 frequent absentees. Focus group discussions were audiotaped and transcribed verbatim. Results were analyzed with the Graneheim method using the Job Demands Resources (JD-R) model as theoretical framework. Many participants were not aware of their frequent sickness absence and the risk of future long-term sickness absence. As determinants, participants mentioned job demands, job resources, home demands, poor health, chronic illness, unhealthy lifestyles, and diminished feeling of responsibility to attend work in cases of low job resources. Managing these factors and improving communication (skills) were regarded as solutions to reduce frequent sickness absence. The JD-R model provided a framework for determinants of and solutions to frequent sickness absence. Additional determinants were poor health, chronic illness, unhealthy lifestyles, and diminished feeling of responsibility to attend work in cases of low job resources. Frequent sickness absence should be regarded as a signal that something is wrong. Managers, supervisors, and occupational health care providers should advise and support frequent absentees to accommodate job demands, increase both job and personal resources, and improve health rather than express disapproval of frequent sickness absence and apply pressure regarding work attendance.

  11. Investigation of point triangulation methods for optimality and performance in Structure from Motion systems

    DEFF Research Database (Denmark)

    Structure from Motion (SFM) systems are composed of cameras and structure in the form of 3D points and other features. It is most often that the structure components outnumber the cameras by a great margin. It is not uncommon to have a configuration with 3 cameras observing more than 500 3D points...... an overview of existing triangulation methods with emphasis on performance versus optimality, and will suggest a fast triangulation algorithm based on linear constraints. The structure and camera motion estimation in a SFM system is based on the minimization of some norm of the reprojection error between...

  12. Does self-efficacy predict return-to-work after sickness absence? A prospective study among 930 employees with sickness absence for three weeks or more

    DEFF Research Database (Denmark)

    Labriola, Merete; Lund, Thomas; Christensen, Karl B

    2007-01-01

    follows a cohort of 5357 working employees and 106 long-term sickness absent employees in Denmark. They were interviewed in 2000 regarding self-efficacy and various co-variates, and followed for 78 weeks in a national sickness absence register. Cox regression analysis was performed in order to assess...... or with Return-to-Work. CONCLUSION: The results may suggest that lower self-efficacy among employees with sickness absence is a result of the sickness absence itself rather than a precursor of it. This indicates a need to investigate the potential change in self-efficacy in relation to the employee's change......AIM: To compare levels of self-efficacy among the general working population and employees with sickness absence from work, and to examine if general self-efficacy measured before occurrence of sickness absence predicted subsequent onset of sickness absence and Return-to-Work. METHODS: The study...

  13. Social inequalities in "sickness"

    DEFF Research Database (Denmark)

    van der Wel, Kjetil A; Dahl, Espen; Thielen, Karsten

    2012-01-01

    In comparative studies of health inequalities, public health researchers have usually studied only disease and illness. Recent studies have also examined the sickness dimension of health, that is, the extent to which ill health is accompanied by joblessness, and how this association varies...... consistent results. They analyze data from the European Union Statistics on Income and Living Conditions (EU-SILC); health was measured by limiting longstanding illness (LLSI). Results show that for both men and women reporting LLSI in combination with low educational level, the probabilities of non......-employment were particularly high in the Anglo-Saxon and Eastern welfare regimes, and lowest in the Scandinavian regime. For men, absolute and relative social inequalities in sickness were lowest in the Southern regime; for women, inequalities were lowest in the Scandinavian regime. The authors conclude...

  14. ACUTE MOUNTAIN SICKNESS

    Directory of Open Access Journals (Sweden)

    Jakub Krzeszowiak

    2012-03-01

    Full Text Available This paper presents the most likely pathophysiological causes of the development of acute mountain sickness (AMS, also known as altitude sickness, its pulmonary form i.e. high altitude pulmonary edema (HAPE, and high altitude cerebral edema (HACE. These diseases constitute extraordinary environmental hazards because they are directly connected with low atmospheric pressure, and thus low partial oxygen pressure. The above adverse atmospheric conditions start to affect humans already at an altitude of 2,500 meters above the sea level and, coupled with extreme physical exertion, can quickly lead to respiratory alkalosis, which is not present under any other conditions in the lowlands. Mountaineering above 4,500 m a.s.l. leads to hypoxia of internal organs and, primarily, reduced renal perfusion with all its consequences. The above adverse changes, combined with inadequate acclimatization, can lead to a situation of imminent danger to life and health. This paper describes in detail the consequences of acute mountain sickness, which can ultimately lead to the development of AMS and one of severe forms of HACE and/or HAPE.

  15. Investigation of the Rolling Motion of a Hollow Cylinder Using a Smartphone's Digital Compass

    Science.gov (United States)

    Wattanayotin, Phattara; Puttharugsa, Chokchai; Khemmani, Supitch

    2017-01-01

    This study used a smartphone's digital compass to observe the rolling motion of a hollow cylinder on an inclined plane. The smartphone (an iPhone 4s) was attached to the end of one side of a hollow cylinder to record the experimental data using the SensorLog application. In the experiment, the change of angular position was measured by the…

  16. Human Kinematics of Cochlear Implant Surgery: An Investigation of Insertion Micro-Motions and Speed Limitations.

    Science.gov (United States)

    Kesler, Kyle; Dillon, Neal P; Fichera, Loris; Labadie, Robert F

    2017-09-01

    Objectives Document human motions associated with cochlear implant electrode insertion at different speeds and determine the lower limit of continuous insertion speed by a human. Study Design Observational. Setting Academic medical center. Subjects and Methods Cochlear implant forceps were coupled to a frame containing reflective fiducials, which enabled optical tracking of the forceps' tip position in real time. Otolaryngologists (n = 14) performed mock electrode insertions at different speeds based on recommendations from the literature: "fast" (96 mm/min), "stable" (as slow as possible without stopping), and "slow" (15 mm/min). For each insertion, the following metrics were calculated from the tracked position data: percentage of time at prescribed speed, percentage of time the surgeon stopped moving forward, and number of direction reversals (ie, going from forward to backward motion). Results Fast insertion trials resulted in better adherence to the prescribed speed (45.4% of the overall time), no motion interruptions, and no reversals, as compared with slow insertions (18.6% of time at prescribed speed, 15.7% stopped time, and an average of 18.6 reversals per trial). These differences were statistically significant for all metrics ( P implant electrode at 15 mm/min is not feasible for human operators. The lower limit of continuous forward insertion is 52 mm/min on average. Guidelines on manual insertion kinematics should consider this practical limit of human motion.

  17. 20 CFR 218.28 - Sick pay.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Sick pay. 218.28 Section 218.28 Employees... Beginning Date § 218.28 Sick pay. (a) From railroad employer. If the employee is carried on the payroll while sick, the annuity can begin no earlier than the day after the last day of sick pay. However, sick...

  18. Investigation of the rolling motion of a hollow cylinder using a smartphone

    Science.gov (United States)

    Puttharugsa, Chokchai; Khemmani, Supitch; Utayarat, Patipan; Luangtip, Wasutep

    2016-09-01

    This paper describes the use of smartphone’s gyroscope sensor to analyse a hollow cylinder rolling down an inclined plane. The smartphone (iPhone 4s) was attached to the end of hollow cylinder and was equipped with the Sensorlog application (Sensorlog app) to record the angular speed of rolling down an inclined plane. The experimental results agree with the theoretical model that is familiar to students for the rolling motion on an inclined plane. Moreover, the coefficients of static friction and kinetic friction were determined to be 0.205 ± 0.011 and 0.178 ± 0.003 from the measurements, respectively. This experiment demonstrated an alternative way to teach the rolling motion in a physics laboratory.

  19. Investigating wake patterns and propulsive frequencies of a flat plate under pitching motion

    Science.gov (United States)

    Moubogha Moubogha, Joseph; Astolfi, Jacques Andre

    Fundamental mechanisms of swimming are explored using a simple geometry device - flat plate - in pure-pitching motion in a hydrodynamic tunnel. The experiments are carried out at different Reynolds numbers based on the plate length c. Pitching motion is generated for reduced frequencies k between 0 and 2 and for an angular amplitude of 10 deg. Velocity fields are obtained in the wake of the plate using Particle Image Velocimetry and measurements of drag coefficients are estimated from mean velocity profiles. This study confirms the occurrence of a threshold oscillation frequency beyond which the plate enters a propulsive regime and the wake features organized structures. In this case an inversion of the typical Karman vortex street is observed. The evolution of mean transverse velocity profiles in the wake of the plate shows that the usual wake profile with velocity deficit - plate with drag - can be transformed into a jet - plate with thrust - above a certain reduced frequency. Phd Student Mechanical Engineering Departement.

  20. Investigation on the radial micro-motion about piston of axial piston pump

    Science.gov (United States)

    Xu, Bing; Zhang, Junhui; Yang, Huayong; Zhang, Bin

    2013-03-01

    The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.

  1. Sickness absence at a young age and later sickness absence, disability pension, death, unemployment and income in native Swedes and immigrants

    Science.gov (United States)

    Johansson, Bo; Nordqvist, Tobias; Lundberg, Ingvar; Vingård, Eva

    2015-01-01

    Background: Sickness absence with cash benefits from the sickness insurance gives an opportunity to be relieved from work without losing financial security. There are, however, downsides to taking sickness absence. Periods of sickness absence, even short ones, can increase the risk for future spells of sickness absence and unemployment. The sickness period may in itself have a detrimental effect on health. The aim of the study was to investigate if there is an association between exposure to sickness absence at a young age and later sickness absence, disability pension, death, unemployment and income from work. Methods: Our cohort consisted of all immigrants aged 21–25 years in Sweden in 1993 (N = 38 207) and a control group of native Swedes in the same age group (N = 225 977). We measured exposure to sickness absence in 1993 with a follow-up period of 15 years. We conducted separate analyses for men and women, and for immigrants and native Swedes. Results: Exposure to ≥60 days of sickness absence in 1993 increased the risk of sickness absence [hazard ratio (HR) 1.6–11.4], unemployment (HR 1.1–1.2), disability pension (HR 1.2–5.3) and death (HR 1.2–3.5). The income from work, during the follow-up period, among individuals with spells of sick leave for ≥60 days in 1993 was around two-thirds of that of the working population who did not take sick leave. Conclusions: Individuals on sickness absence had an increased risk for work absence, death and lower future income. PMID:25634955

  2. Morning Sickness: Nausea and Vomiting of Pregnancy

    Science.gov (United States)

    ... About ACOG Morning Sickness: Nausea and Vomiting of Pregnancy Home For Patients Search FAQs Morning Sickness: Nausea ... PDF Format Morning Sickness: Nausea and Vomiting of Pregnancy Pregnancy How common is nausea and vomiting of ...

  3. Decompression sickness in caisson workers

    Science.gov (United States)

    Ghawabi, Samir H. El; Mansour, Mohamed B.; Youssef, Fatma L.; Ghawabi, Mohamed H. El; Latif, Mohamed M. Abd El

    1971-01-01

    El Ghawabi, S. H., Mansour, M. B., Youssef, F. L., El Ghawabi, M. H., and Abd El Latif, M. M. (1971).Brit. J. industr. Med.,28, 323-329. Decompression sickness in caisson workers. An investigation of 55 bridge construction workers is reported. The overall bends rate was 0·97%. (The term `bends' as used in this study is defined in the paper.) Chokes were encountered in 67·27% of workers. A clinical, haematological, and radiological study was performed. Definite bony changes were found in 43·6% of all workers; 91·6% of these had lesions around the elbow. The presence of dense areas in the neck of the scapula is reported in two cases for the first time. The relatively high haematocrit value is thought to play a part in the pathogenesis of bone infarction through its relation with blood viscosity. Images PMID:5124832

  4. Workplace bullying and sickness presenteeism

    DEFF Research Database (Denmark)

    Conway, Paul Maurice; Clausen, Thomas; Hansen, Åse Marie

    2016-01-01

    Purpose: The aim of this study is to investigate exposure to workplace bullying as a potential risk factor for sickness presenteeism (SP), i.e., working while ill. Methods: This study is based on data collected through self-reported questionnaires in a 2-year prospective study on employees...... with missing values, the final samples were composed of 2,865 and 1,331participants in the cross-sectional and prospective analyses, respectively. Results: Modified poisson regression analyses showed that frequent (i.e., daily or weekly) exposure to workplace bullying was associated with reporting 8 or more...... indications of a significant relationship between exposure to frequent workplace bullying and SP, although causal connections could not be established. Methodological and theoretical considerations about study findings are provided, which could be of benefit to future studies examining the impact of being...

  5. Investigation of domain wall motion in RE-TM magnetic wire towards a current driven memory and logic

    Energy Technology Data Exchange (ETDEWEB)

    Awano, Hiroyuki

    2015-06-01

    Current driven magnetic domain wall (DW) motions of ferri-magnetic TbFeCo wires have been investigated. In the case of a Si substrate, the critical current density (Jc) of DW motion was successfully reduced to 3×10{sup 6} A/cm{sup 2}. Moreover, by using a polycarbonate (PC) substrate with a molding groove of 600 nm width, the Jc was decreased to 6×10{sup 5} A/cm{sup 2}. In order to fabricate a logic in memory, a current driven spin logics (AND, OR, NOT) have been proposed and successfully demonstrated under the condition of low Jc. These results indicate that TbFeCo nanowire is an excellent candidate for next generation power saving memory and logic.

  6. Investigating the role of sliding friction in rolling motion: a teaching sequence based on experiments and simulations

    Science.gov (United States)

    De Ambrosis, Anna; Malgieri, Massimiliano; Mascheretti, Paolo; Onorato, Pasquale

    2015-05-01

    We designed a teaching-learning sequence on rolling motion, rooted in previous research about student conceptions, and proposing an educational reconstruction strongly centred on the role of friction in different cases of rolling. A series of experiments based on video analysis is used to highlight selected key concepts and to motivate students in their exploration of the topic; and interactive simulations, which can be modified on the fly by students to model different physical situations, are used to stimulate autonomous investigation in enquiry activities. The activity sequence was designed for students on introductory physics courses and was tested with a group of student teachers. Comparisons between pre- and post-tests, and between our results and those reported in the literature, indicate that students’ understanding of rolling motion improved markedly and some typical difficulties were overcome.

  7. Model development of SAS4A and investigation on the initiating phase consequences in LMFRs related with material motion

    International Nuclear Information System (INIS)

    Niwa, H.

    1994-01-01

    This paper focuses on an analytical aspect of the initiating phase scenario and consequences of postulated core disruptive accident in liquid-metal-cooled fast breeder reactors. An analytical code, SAS4A, has been developed at Argonne National Laboratory, and introduced to PNC. Improvement and validation effort have been performed for the mixed-oxide version of SAS4A at PNC. This paper describes firstly recent development of SAS4A's material motion related models briefly. A fission gas mass transfer model and solid fuel chunk jamming model are developed and introduced to SAS4A, and validated using CABRI-2 E13 experimental data. Secondly, an investigation of the mechanism of energetics in the initiating phase of an unprotected loss-of-flow accident has identified major control parameters which are intimately related to core design parameters and material motion phenomena. (author)

  8. Standing body sway in women with and without morning sickness in pregnancy.

    Science.gov (United States)

    Yu, Yawen; Chung, Hyun Chae; Hemingway, Lauren; Stoffregen, Thomas A

    2013-01-01

    Morning sickness typically is attributed to hormonal changes in pregnancy. We asked whether morning sickness is associated with changes in standing postural equilibrium, as occurs in research on visually induced motion sickness. Twenty-one pregnant women (mean age=30 years, mean height=163cm; mean weight=63kg) were tested during the first trimester. Laboratory-based balance measures were collected, along with perceived postural stability, the presence of morning sickness, and the severity of subjective symptoms. We varied the distance between the feet and the visual task performed during stance. Participants were classified as either experiencing (Sick, n=12) or not experiencing (Well, n=9) morning sickness. Perceived balance stability was lower for Sick than for Well women. The positional variability of sway was reduced for the Sick group, relative to the Well group. Positional variability decreased with wider stance width, and was reduced during performance of a more demanding visual task. Stance width and visual task also influenced the temporal dynamics of sway. Effects of stance width and visual task on postural sway were similar to effects in non-pregnant adults, suggesting that sensitive tuning of posture is maintained during the first trimester. The findings suggest that women with morning sickness may attempt to stabilize their bodies by reducing overall body sway. It may be useful to recommend that women adopt wider stance early in pregnancy. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Sickness and love: an introduction

    NARCIS (Netherlands)

    van der Geest, S.; Vandamme, S.

    2008-01-01

    Love is a neglected topic in anthropology, for good reasons: it has always resisted scientific definition and analysis. By associating love with sickness seven authors attempt to capture various meanings and experiences of love. Two broad concepts arise: love as sickness and love in response to

  10. Modeling and experimental investigation of an impact-driven piezoelectric energy harvester from human motion

    International Nuclear Information System (INIS)

    Wei, Sheng; Hu, Hong; He, Siyuan

    2013-01-01

    An impact-driven piezoelectric energy harvester from human motion is proposed in this paper. A high-frequency PZT-5A bimorph cantilever beam with attached proof mass at the free end was selected. A frequency up-conversion strategy was realized using impulse force generated by human motion. An aluminum prototype was attached to the leg of a person on a treadmill and measurements taken of the dissipated electric energy across multiple resistances over a range of walking speeds. The outer dimensions of this prototype are 90 mm × 40 mm × 24 mm. It has been shown that the average output voltage generated by the piezoelectric bimorph increases sequentially with a faster walking speed, the power varies with the external resistances and maximum levels occur at the optimal resistance, which is consistent with the simulation result. An open circuit voltage of 2.47 V and maximum average power of 51 μW can be achieved across a 20 kΩ external load resistance and 5 km h −1 walking speed. Experimental results reveal that the impact-driven piezoelectric energy harvesting system mounted on a person’s leg has the potential for driving wearable devices. (paper)

  11. Methyl group rotation and segmental motion in atactic polypropylene. An incoherent quasi elastic neutron scattering investigation

    International Nuclear Information System (INIS)

    Arrighi, V.; Triolo, A.

    1999-01-01

    Complete text of publication follows. Results from the analysis of recent quasielastic neutron scattering (QENS) experiments on atactic polypropylene (aPP), are presented both in the sub-T g and above T g regimes. Experiments were carried out on the IRIS (ISIS, Rutherford Appleton Laboratory, UK) and IN10 (ILL FR) spectrometers in the temperature range from 140 to 400 K. Different instrumental resolutions were used in order to cover a wide energy window. The high resolution data collected on IN10 using the fixed energy scan technique, give clear evidence of two separate dynamic processes that we attribute to methyl group rotational hopping (below T g ) and to segmental motion (above T g ), respectively. Data were fitted using a model involving a distribution of relaxation rates. The IN10 results are used in interpreting and analyzing the QENS data from the IRIS spectrometer. In order to exploit the different energy resolutions of IRIS, Fourier inversion of the experimental data was carried out. This approach to data analysis allows us to widen the energy range available for data analysis. Due to the high activation energy of the methyl group hopping in aPP, this motion overlaps with the segmental relaxation, thus making analysis of high temperature data quite complex. The IN10 results are employed in order to perform data analysis in terms of two distinct processes. (author)

  12. Managerial leadership is associated with self-reported sickness absence and sickness presenteeism among Swedish men and women.

    Science.gov (United States)

    Nyberg, Anna; Westerlund, Hugo; Magnusson Hanson, Linda L; Theorell, Töres

    2008-11-01

    The objective of this study was to investigate the relationship between managerial leadership and self-reported sickness absence/presenteeism among Swedish men and women. Five thousand one hundred and forty-one Swedish employees, 56% of the participants in a nationally representative sample of the Swedish working population, were included in this cross-sectional questionnaire study. The leadership dimensions measured were five subscales of a standardized leadership questionnaire (Global Leadership and Organizational Behaviour Effectiveness Programme): Integrity, Team integration, Inspirational leadership, Autocratic leadership, and Self-centred leadership. Multiple logistic regression analyses were conducted, adjusting for factors in private life, employment category, labour-market sector, working conditions, self-reported general health, and satisfaction with life in general. Inspirational leadership was associated with a lower rate of short spells of sickness absence (women. Autocratic leadership was related to a greater amount of total sick days taken by men. Sometimes showing integrity was associated with higher rate of sickness absence >1 week among men, and seldom showing integrity was associated with more sickness presenteeism among women. Managers performing Team integration were sometimes associated with women taking fewer short (1 week) spells of sickness absence. Adjustment for self-reported general health did not alter these associations for men, but did so to some extent for women. Managerial leadership was found to be relevant for the understanding of sickness absence in the Swedish working population. There were distinctive gender differences.

  13. GPs' negotiation strategies regarding sick leave for subjective health complaints.

    Science.gov (United States)

    Nilsen, Stein; Malterud, Kirsti; Werner, Erik L; Maeland, Silje; Magnussen, Liv Heide

    2015-03-01

    To explore general practitioners' (GPs') specific negotiation strategies regarding sick-leave issues with patients suffering from subjective health complaints. Focus-group study. Nine focus-group interviews in three cities in different regions of Norway. 48 GPs (31 men, 17 women; age 32-65), participating in a course dealing with diagnostic practice and assessment of sickness certificates related to patients with subjective health complaints. The GPs identified some specific strategies that they claimed to apply when dealing with the question of sick leave for patients with subjective health complaints. The first step would be to build an alliance with the patient by complying with the wish for sick leave, and at the same time searching for information to acquire the patient's perspective. This position would become the basis for the main goal: motivating the patient for a rapid return to work by pointing out the positive effects of staying at work, making legal and moral arguments, and warning against long-term sick leave. Additional solutions might also be applied, such as involving other stakeholders in this process to provide alternatives to sick leave. GPs seem to have a conscious approach to negotiations of sickness certification, as they report applying specific strategies to limit the duration of sick leave due to subjective health complaints. This give-and-take way of handling sick-leave negotiations has been suggested by others to enhance return to work, and should be further encouraged. However, specific effectiveness of this strategy is yet to be proven, and further investigation into the actual dealings between doctor and patients in these complex encounters is needed.

  14. An EPR investigation of room temperature radiation damage and molecular motion in the ferroelectric phosphates

    International Nuclear Information System (INIS)

    Dalal, N.S.; Herak, J.N.; McDowell, C.A.

    1976-01-01

    Several types of paramagnetic centers have been detected in the room temperature irradiated KH 2 PO 4 , KD 2 PO 4 , KH 2 PO 4 -KH 2 AsO 4 , KD 2 PO 4 -KD 2 AsO 4 and in the newly discovered ferroelectric NaTh 2 (PO 4 ) 3 . Comparative studies of temperature dependence in the EPR spectra show that as in KH 2 PO 4 -type crystals, the ferroelectric phase transition in NaTh 2 (PO 4 ) 3 crystals also seems to be related to the motion of the PO 4 units. The results help to clarify some earlier observed anomalies on the effects of γ-irradiation on dielectric properties of KH 2 PO 4 and in particular, show that the extent of the damage can be controlled by changing the impurity content of the unirradiated samples. (Auth.)

  15. Investigating dislocation motion through a field of solutes with atomistic simulations and reaction rate theory

    International Nuclear Information System (INIS)

    Saroukhani, S.; Warner, D.H.

    2017-01-01

    The rate of thermally activated dislocation motion across a field of solutes is studied using traditional and modern atomistically informed rate theories. First, the accuracy of popular variants of the Harmonic Transition State Theory, as the most common approach, is examined by comparing predictions to direct MD simulations. It is shown that HTST predictions are grossly inaccurate due to the anharmonic effect of thermal softening. Next, the utility of the Transition Interface Sampling was examined as the method was recently shown to be effective for predicting the rate of dislocation-precipitate interactions. For dislocation-solute interactions studied here, TIS is found to be accurate only when the dislocation overcomes multiple obstacles at a time, i.e. jerky motion, and it is inaccurate in the unpinning regime where the energy barrier is of diffusive nature. It is then shown that the Partial Path TIS method - designed for diffusive barriers - provides accurate predictions in the unpinning regime. The two methods are then used to study the temperature and load dependence of the rate. It is shown that Meyer-Neldel (MN) rule prediction of the entropy barrier is not as accurate as it is in the case of dislocation-precipitate interactions. In response, an alternative model is proposed that provides an accurate prediction of the entropy barrier. This model can be combined with TST to offer an attractively simple rate prediction approach. Lastly, (PP)TIS is used to predict the Strain Rate Sensitivity (SRS) factor at experimental strain rates and the predictions are compared to experimental values.

  16. Experimental investigation of snap-through motion of in-plane MEMS shallow arches under electrostatic excitation

    KAUST Repository

    Ramini, Abdallah

    2015-12-11

    We present an experimental investigation for the nonlinear dynamic behaviors of clamped–clamped in-plane MEMS shallow arches when excited by harmonic electrostatic forces. Frequency sweeps are conducted to study the dynamic behaviors in the neighborhoods of the first and third resonance frequencies as well as the super-harmonic resonances. Experimental results show local softening behavior of small oscillations around the first resonance frequency and hardening behavior at the third resonance frequency for small dc and ac loads. Interesting dynamic snap-through cross-well motions are observed experimentally at high voltages for the first time in the micro-scale world. In addition to the dynamic snap-through motion, the MEMS arch exhibits large oscillations of a continuous band of snap-through motion between the super-harmonic resonance regime and the first primary resonance regime. This continuous band is unprecedented experimentally in the micro/macro world, and is promising for a variety of sensing, actuation and communications applications.

  17. Experimental investigation of snap-through motion of in-plane MEMS shallow arches under electrostatic excitation

    KAUST Repository

    Ramini, Abdallah; Bellaredj, Mohammed L F; Al Hafiz, Md Abdullah; Younis, Mohammad I.

    2015-01-01

    We present an experimental investigation for the nonlinear dynamic behaviors of clamped–clamped in-plane MEMS shallow arches when excited by harmonic electrostatic forces. Frequency sweeps are conducted to study the dynamic behaviors in the neighborhoods of the first and third resonance frequencies as well as the super-harmonic resonances. Experimental results show local softening behavior of small oscillations around the first resonance frequency and hardening behavior at the third resonance frequency for small dc and ac loads. Interesting dynamic snap-through cross-well motions are observed experimentally at high voltages for the first time in the micro-scale world. In addition to the dynamic snap-through motion, the MEMS arch exhibits large oscillations of a continuous band of snap-through motion between the super-harmonic resonance regime and the first primary resonance regime. This continuous band is unprecedented experimentally in the micro/macro world, and is promising for a variety of sensing, actuation and communications applications.

  18. Sick boat syndrome

    Directory of Open Access Journals (Sweden)

    Dąbrowiecki Zbigniew

    2015-12-01

    Full Text Available Many pathogenic micro-organisms are likely to attack passengers of cruise ships and other vessels or travel between continents as a peculiar type of a “stowaway”. The epidemiological tests conducted since 1987 with regard to watercraft led to the coining of a term known as the Sick Boat Syndrome (SBS. The main illnesses encountered on watercraft include gastrointestinal diseases (foodborne and Legionellosis. Additionally, the ventilation and airconditioning systems of old commercial ships (the so-called Tramps constitute a real technical challenge. Conditioned air (with removed undesired odour and micro-organisms should constitute ca. 25% of circulating air. In practice this situation is not typical for vessels of this class. Unclean air poses a real hazard for the crew.

  19. Social inequalities in 'sickness'

    DEFF Research Database (Denmark)

    Wel, Kjetil A. van der; Dahl, Espen; Thielen, Karsten

    2011-01-01

    The aim of this paper is to examine educational inequalities in the risk of non-employment among people with illnesses and how they vary between European countries with different welfare state characteristics. In doing so, the paper adds to the growing literature on welfare states and social...... from Eurostat and OECD that include spending on active labour market policies, benefit generosity, income inequality, and employment protection. Using multilevel techniques we find that comprehensive welfare states have lower absolute and relative social inequalities in sickness, as well as more...... inequalities in health by studying the often overlooked ‘sickness’-dimension of health, namely employment behaviour among people with illnesses. We use European Union Statistics on Income and Living Conditions (EU-SILC) data from 2005 covering 26 European countries linked to country characteristics derived...

  20. [Workplace bullying and sickness absenteeism].

    Science.gov (United States)

    Campanini, Paolo; Conway, Paul Maurice; Neri, Luca; Punzi, Silvia; Camerino, Donatella; Costa, Giovanni

    2013-01-01

    To assess the relationship between workplace bullying and sickness absenteeism in a large sample of Italian workers. A cross-sectional study conducted by means of questionnaires. In all, 8,992 subjects filled in a questionnaire to detect workplace bullying, the presence of work stress factors and days of sickness absence in the last year. Workplace bullying and psychosocial stressor were measured by the means of the CDL 2.0 questionnaire. Days of sickness absence reported by the subjects. On average, days of sickness absence were 7.4, and 7.2% of the respondents were defined as bullied. Results from logistic regression analyses showed that a workplace bullying was associated with more days of sickness absence after controlling for gender, age, professional qualification, company sector and juridical nature and other psychosocial factors (men: OR =1.62; women: OR =2.15). The present study confirms that workers exposed to a workplace bullying reported higher sickness absenteeism as compared with non-exposed subjects, also when a potentially highly stressful work environment is considered. The results of the present study support that workplace bullying may be viewed as an extreme stressful condition. Interventions to avoid workplace bullying not only favoure workers' health, but also avoid the company costs associated with workers' sickness absenteeism.

  1. Job demands, job resources, and behavior in times of sickness

    DEFF Research Database (Denmark)

    Schneider, Daniel; Winter, Vera; Schreyögg, Jonas

    2017-01-01

    BACKGROUND: The concept of presenteeism, that is, employees coming to work despite being sick, has recently received more attention in the literature. Presenteeism not only threatens employees' health but also substantially drains productivity and drives considerable costs. When they are sick......, employees have the choice of whether to go to work or to stay at home. Therefore, determinants of (sickness) absenteeism and presenteeism should be examined simultaneously. Nursing homes are faced with a particularly high prevalence of both absenteeism and presenteeism and are therefore a relevant object...... of investigation. PURPOSE: The aim of our study is to analyze the effect of job demands and job resources on absenteeism, presenteeism, and the tendency to choose one behavior (being absent or being present in times of sickness) rather than the other over the last 12 months. To do so, we identify the determinants...

  2. Contributions to the European workshop on investigation of strong motion processing procedures

    International Nuclear Information System (INIS)

    Mohammadioun, B.; Goula, X.; Hamaide, D.

    1985-11-01

    The first paper is one contribution to a joint study program in the numerical processing of accelerograms from strong earthquakes. A method is proposed for generating an analytic signal having characteristics similar to those of an actual ground displacement. From this signal, a simulated accelerogram is obtained analytically. Various numerical processing techniques are to be tested using this signal: the ground displacements they yield will be compared with the original analytic signal. The second contribution deals with a high-performance digitization complex, custom-designed to stringent technical criteria by the CISI Petrole Services, which has recently been put into service at the Bureau d'Evaluation des Risques Sismiques pour la Surete des Installations Nucleaires. Specially tailored to cope with the problems raised by the sampling of Strong-Motion photographic recordings, it offers considerable flexibility, due to its self-teaching conception, constant monitoring of the work ongoing, and numerous preprocessing options. In the third contribution, a critical examination of several processing techniques applicable to photographic recordings of SMA-1 type accelerometers is conducted. The basis for comparison was a set of two accelerograms drawn from synthetic signals, the characteristics of which were already well known

  3. Industrial Sickness in Indian Manufacturing

    OpenAIRE

    Falk, Rahel

    2005-01-01

    In India, the term ‘sick units’ refers to economically unviable firms which are kept alive ‘in the public interest’ by means of subsidies of various kinds. Since this practice is common, and large parts of the industrial sector are affected, this phenomenon is referred to as industrial sickness. As of March 2001, the Reserve Bank of India counted over a quarter of a million of sick units with outstanding credit worth more than a quarter of a trillion of Indian Rupees, i.e. about 1.2 percent o...

  4. Psychiatric legal investigation for sickness benefits due to disability at the Brazilian Federal Social Security Special Court in Florianópolis, capital city of the State of Santa Catarina, southern Brazil.

    Science.gov (United States)

    Figueredo, Roberto; Damas, Fernando Balvedi

    2015-01-01

    To describe the profile of insured individuals that filed claims for sickness benefits and compare the results of the administrative and legal investigations. This case series included 114 insured persons that filed lawsuits against the Brazilian National Institute of Social Security (Instituto Nacional de Seguridade Social, INSS). They underwent psychiatric examinations required by the Brazilian Federal Social Security Special Court in Florianópolis from August to December 2010. Mean age was 47 years, and participant age ranged from 24 to 64 years. Most insured individuals were women (79%), and most were employed (67.5%) and self-employed (26.5%) workers. Mean contribution time was 99.9 months, ranging from 8 to 352 months. Mean benefit duration was 20.4 months, ranging from 2 to 97 months. The most prevalent category of workers was service workers, store and supermarket salespeople (54.4%), followed by administrative workers (19.3%). Only 17 participants were found to be unable to work after benefit cessation, a 14.9% mismatch between administrative and legal investigations. The most frequent diagnoses were mood disorders (59.6%) and anxiety disorders (17.5%).

  5. Psychiatric legal investigation for sickness benefits due to disability at the Brazilian Federal Social Security Special Court in Florianópolis, capital city of the State of Santa Catarina, southern Brazil

    Directory of Open Access Journals (Sweden)

    Roberto Figueredo

    2015-06-01

    Full Text Available Objective: To describe the profile of insured individuals that filed claims for sickness benefits and compare the results of the administrative and legal investigations.Method: This case series included 114 insured persons that filed lawsuits against the Brazilian National Institute of Social Security (Instituto Nacional de Seguridade Social, INSS. They underwent psychiatric examinations required by the Brazilian Federal Social Security Special Court in Florianópolis from August to December 2010.Results: Mean age was 47 years, and participant age ranged from 24 to 64 years. Most insured individuals were women (79%, and most were employed (67.5% and self-employed (26.5% workers. Mean contribution time was 99.9 months, ranging from 8 to 352 months. Mean benefit duration was 20.4 months, ranging from 2 to 97 months. The most prevalent category of workers was service workers, store and supermarket salespeople (54.4%, followed by administrative workers (19.3%.Conclusions: Only 17 participants were found to be unable to work after benefit cessation, a 14.9% mismatch between administrative and legal investigations. The most frequent diagnoses were mood disorders (59.6% and anxiety disorders (17.5%.

  6. [Temporal Analysis of Body Sway during Reciprocator Motion Movie Viewing].

    Science.gov (United States)

    Sugiura, Akihiro; Tanaka, Kunihiko; Wakatabe, Shun; Matsumoto, Chika; Miyao, Masaru

    2016-01-01

    We aimed to investigate the effect of stereoscopic viewing and the degree of awareness of motion sickness on posture by measuring body sway during motion movie viewing. Nineteen students (12 men and 7 women; age range, 21-24 years) participated in this study. The movie, which showed several balls randomly positioned, was projected on a white wall 2 m in front of the subjects through a two-dimensional (2-D)/three-dimensional (3-D) convertible projector. To measure body sway during movie viewing, the subjects stood statically erect on a Wii balance board, with the toe opening at 18 degrees. The study protocol was as follows: The subjects watched (1) a nonmoving movie for 1 minute as the pretest and then (2) a round-trip sinusoidally moving-in-depth-direction movie for 3 minutes. (3) The initial static movie was shown again for 1 minute. Steps (2) and (3) were treated as one trial, after which two trials (2-D and 3-D movies) were performed in a random sequence. In this study, we found that posture changed according to the motion in the movie and that the longer the viewing time, the higher the synchronization accuracy. These tendencies depended on the level of awareness of motion sickness or the 3-D movie viewed. The mechanism of postural change in movie viewing was not vection but self-defense to resolve sensory conflict between visual information (spatial swing) and equilibrium sense (motionlessness).

  7. The effects of area postrema lesions and selective vagotomy on motion-induced conditioned taste aversion

    Science.gov (United States)

    Fox, Robert A.; Sutton, R. L.; Mckenna, Susan

    1991-01-01

    Conditioned taste aversion (CTA) is one of several behaviors which was suggested as a putative measure of motion sickness in rats. A review is made of studies which used surgical disruption of area postrema or the vagus nerve to investigate whether CTA and vomiting induced by motion may depend on common neural pathways or structures. When the chemoreceptive function of the area postrema (AP) is destroyed by complete ablation, rats develop CTA and cats and monkeys develop CTA and vomit. Thus the AP is not crucially involved in either CTA or vomiting induced by motion. However, after complete denervation of the stomach or after labyrinthectomy rats do not develop CTA when motion is used as the unconditioned stimulus. Studies of brainstem projections of the vagus nerve, the area postrema, the periaqueductal grey, and the vestibular system are used as the basis for speculation about regions which could mediate both motion-induced vomiting and behavioral food aversion.

  8. The association between health and sickness absence among Danish and non-Western immigrant cleaners in Denmark.

    Science.gov (United States)

    Carneiro, Isabella G; Rasmussen, Charlotte D N; Jørgensen, Marie B; Flyvholm, Mari-Ann; Olesen, Kasper; Madeleine, Pascal; Ekner, Dorte; Søgaard, Karen; Holtermann, Andreas

    2013-05-01

    The aim of the study is to investigate the association between health and sickness absence among Danish and non-Western immigrant cleaners in Denmark. This study is based on a cross-sectional analysis of baseline data from 2007 to 2008. The study population includes 276 cleaners, 144 Danish and 132 non-Western immigrant cleaners. Cumulative sickness absences during a 6-month period from administrative records were subdivided into no sickness absence (0 days), low occurrence of sickness absence (1-10 days) and high occurrence of sickness absence (over 10 days). Measures of health consisted of self-report and objective assessments. The relationship between sickness absence and health was analyzed through multinomial logistic regression, stratified by immigrant status. For both Danish and non-Western immigrant cleaners, poor self-reported health was significantly related to high occurrence of sickness absence. Among Danish cleaners, high blood pressure was related to high occurrence of sickness absence. Among non-Western immigrant cleaners, total body pain and having one or more diagnosed chronic disease were related to high occurrence of sickness absence. No association between health and low occurrence of sickness absence was found. The findings confirm the importance of health for high occurrence of sickness absence, in both ethnic groups. Moreover, low occurrence of sickness absence was not related to the health conditions investigated.

  9. Numerical investigation of the effects of geometric parameters on transverse motion with slanted-groove micro-mixers

    Energy Technology Data Exchange (ETDEWEB)

    Baik, Seung Joo; Cho, Jae Yong; Choi, Se Bin; Lee, Joon Sang [School of Mechanical Engineering, Yonsei University, Seoul (Korea, Republic of)

    2016-08-15

    We investigated hydrodynamic phenomena inside several passive microfluidic mixers using a Lattice Boltzmann method (LBM) based on particle mesoscopic kinetic equations. Mixing processes were simulated in a Slanted grooved micro-mixer (SGM), a Staggered herringbone grooved micro-mixer (SHM), and a Bi-layered staggered herringbone grooved micro-mixer (BSHM). Then, the effects of six geometric mixer parameters (i.e., groove height to channel height ratio, groove width to groove pitch length ratio, groove pitch to groove height ratio, groove intersection angle, herringbone groove asymmetric ratio and bi-layered groove asymmetric ratio) on mixing were investigated using computed cross-flow velocity and helicity density distributions in the flow cross-section. We demonstrated that helicity density provides sufficient information to analyze micro helical motion within a micro-mixer, allowing for micro-mixer design optimization.

  10. Paid Sick Leave as a Means to Reduce Sickness Presenteeism Among Physicians

    Directory of Open Access Journals (Sweden)

    Ingrid Steen Rostad

    2017-06-01

    Full Text Available Recurrent international data show that physicians often attend work while ill, termed sickness presenteeism. The current study investigated if sickness presenteeism scores among European physicians varied according to national paid sick leave legislation. We hypothesized that prevalence of presenteeism was higher in countries with lower levels of paid sick leave. We used repeated cross-sectional survey data, phase I (2004/2005, N = 1326 and phase II (2012/2013, N = 1403, among senior consultants at university hospitals in Sweden, Norway, and Italy. Analyses of variances assessed cross-country differences in presenteeism. To assess the impact of country on presenteeism, we used multiple regression analyses controlled for sex, age, family status, work hours, and work content. The results from phase I supported the initial hypothesis. At phase II, presenteeism scores had decreased among the Italian and Swedish sample. The results are discussed with regard to changes in legislation on workhours and medical liability in Italy and Sweden between phase I and II.

  11. Focus Group Study Exploring Factors Related to Frequent Sickness Absence.

    Directory of Open Access Journals (Sweden)

    Annette Notenbomer

    Full Text Available Research investigating frequent sickness absence (3 or more episodes per year is scarce and qualitative research from the perspective of frequent absentees themselves is lacking. The aim of the current study is to explore awareness, determinants of and solutions to frequent sickness absence from the perspective of frequent absentees themselves.We performed a qualitative study of 3 focus group discussions involving a total of 15 frequent absentees. Focus group discussions were audiotaped and transcribed verbatim. Results were analyzed with the Graneheim method using the Job Demands Resources (JD-R model as theoretical framework.Many participants were not aware of their frequent sickness absence and the risk of future long-term sickness absence. As determinants, participants mentioned job demands, job resources, home demands, poor health, chronic illness, unhealthy lifestyles, and diminished feeling of responsibility to attend work in cases of low job resources. Managing these factors and improving communication (skills were regarded as solutions to reduce frequent sickness absence.The JD-R model provided a framework for determinants of and solutions to frequent sickness absence. Additional determinants were poor health, chronic illness, unhealthy lifestyles, and diminished feeling of responsibility to attend work in cases of low job resources. Frequent sickness absence should be regarded as a signal that something is wrong. Managers, supervisors, and occupational health care providers should advise and support frequent absentees to accommodate job demands, increase both job and personal resources, and improve health rather than express disapproval of frequent sickness absence and apply pressure regarding work attendance.

  12. A Field Study of Performance Among Embarked Infantry Personnel Exposed to Waterborne Motion

    Science.gov (United States)

    2012-09-01

    motion sickness. However, the symptoms associated with these sicknesses may also arise in the absence of motion. Cinema sickness and simulator... identical courses were constructed to facilitate the timely completion of 35 the physical coordination course. Participants with an odd identification...nearly identical to the layout at Pelican Point. Figure 9 shows the detailed course layout superimposed over an aerial view of Red Beach

  13. [Teacher sick leave: Prevalence, duration, reasons and covariates].

    Science.gov (United States)

    Vercambre-Jacquot, M-N; Gilbert, F; Billaudeau, N

    2018-02-01

    Absences from work have considerable social and economic impact. In the education sector, the phenomenon is particularly worrying since teacher sick leave has an impact on the overall performance of the education system. Yet, available data are scarce. In April-June 2013, 2653 teachers responded to a population-based postal survey on their quality of life (enquête Qualité de vie des enseignants, MGEN Foundation/Ministry of education, response rate 53 %). Besides questions on work environment and health, teachers were asked to describe their eventual sick leave(s) since the beginning of the school year: duration, type and medical reasons. Self-reported information was reinforced by administrative data from ministerial databases and weighted to be extrapolated to all French teachers. Tobit models adjusted for individual factors of a private nature were used to investigate different occupational risk factors of teacher sick leave, taking into account both the estimated effect on the probability of sick leave and the length of it. More than one in three teachers (36 %) reported having had at least one day of sick leave since the beginning of the school year. Respiratory/ENT diseases were the leading reason for sick leave (37 %). However, and because sick leave duration depended on the underlying health problem, such diseases came in third place among justifications of sick leave days (14 %), far behind musculoskeletal problems (27 %) and neurological and psychological disorders (25 %). Tobit models suggested that some occupational factors significantly associated with the risk of sick leave may represent promising preventive targets, including high psychological demand, workplace violence and unfavorable socio-environmental context. Our study provides objective evidence about the issue of sick leave among French teachers, highlighting the usefulness of implementing actions to minimize its weight. To this end, the study findings point-out the importance of

  14. Investigation on the real-time prediction of ground motions using seismic records observed in deep boreholes

    Science.gov (United States)

    Miyakoshi, H.; Tsuno, S.

    2013-12-01

    The present method of the EEW system installed in the railway field of Japan predicts seismic ground motions based on the estimated earthquake information about epicentral distances and magnitudes using initial P-waves observed on the surface. In the case of local earthquakes beneath the Tokyo Metropolitan Area, however, a method to directly predict seismic ground motions using P-waves observed in deep boreholes could issue EEWs more simply and surely. Besides, a method to predict seismic ground motions, using S-waves observed in deep boreholes and S-wave velocity structures beneath seismic stations, could show planar distributions of ground motions for train operation control areas in the aftermath of earthquakes. This information is available to decide areas in which the emergency inspection of railway structures should be performed. To develop those two methods, we investigated relationships between peak amplitudes on the surface and those in deep boreholes, using seismic records of KiK-net stations in the Kanto Basin. In this study, we used earthquake accelerograms observed in boreholes whose depths are deeper than the top face of Pre-Neogene basement and those on the surface at 12 seismic stations of KiK-net. We selected 243 local earthquakes whose epicenters are located around the Kanto Region. Those JMA magnitudes are in the range from 4.5 to 7.0. We picked the on-set of P-waves and S-waves using a vertical component and two horizontal components, respectively. Peak amplitudes of P-waves and S-waves were obtained using vertical components and vector sums of two horizontal components, respectively. We estimated parameters which represent site amplification factors beneath seismic stations, using peak amplitudes of S-waves observed in the deep borehole and those on the surface, to minimize the residuals between calculations by the theoretical equation and observations. Correlation coefficients between calculations and observations are high values in the range

  15. Investigation of Io's auroral hiss emissions due to its motion in Jupiter's magnetosphere

    International Nuclear Information System (INIS)

    Moghimi, Mohsen H.

    2012-01-01

    The left-hand side of the auroral hiss emission observed by Galileo has a frequency time profile shaped very similar to the funnel shape observed in the Earth's auroral region. This close similarity indicates that we can use the theory of whistler-mode propagation near the resonance cone to locate the emission source. The general characteristics of the whistler mode are discussed. Then the position of the emission source is investigated using a geometrical method that takes into account the trajectory of Galileo. Initially a point source is assumed. Then the possibility of a sheet source aligned along the magnetic field lines which are tangent to the surface of Io is investigated. Both types of sources show that the whistler mode radiation originates very close to the surface of Io. (research papers)

  16. Experimental Investigation of the Motion and Shape of Flexible Objects near a Pump Inlet

    DEFF Research Database (Denmark)

    Jensen, Anna Lyhne; Abou Ackl, Raja; Gerlach, Stefan

    Previous investigations of clogging effects in waste water pumps have focused on the impact of pumping contaminated water on the pump performance, as well as the influence of the operating point on the location of clogged material in the pump and in the pumping system. The present work aims...... to characterise the dynamics of flexible material entering a rotating impeller. Experiments are carried out in a wet pit located in the Department of Fluid System Dynamics in TU Berlin. The wet pit is modified with an acrylic plate placed at the bottom of the pit, enabling visual access to the suction side...

  17. Investigation of the motion processes of wastewater in sewerage of high-rise buildings

    Directory of Open Access Journals (Sweden)

    Pomogaeva Valentina

    2018-01-01

    Full Text Available When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

  18. Investigation of the motion processes of wastewater in sewerage of high-rise buildings

    Science.gov (United States)

    Pomogaeva, Valentina; Metechko, Lyudmila; Prokofiev, Dmitry; Narezhnaya, Tamara

    2018-03-01

    When designing, constructing and operating sewage pipelines in high-rise buildings, issues of failure-free operation of a network arise. Investigation of the processes of wastewater moving allows identifying problem areas during operation, assessing the possibility of obstructions and breakdowns of plumbing traps on the gravity drainage sections of the pipeline. The article performs the schemes of the water outflow from the floor sewer into the riser, including the places where the riser is bent, of air delivery to the working riser under the change of the direction of drain movement with the dropout line set-up, with the installation of an automatic anti-vacuum valve, with the installation of the ventilation pipeline. Investigations of the process of sewage waste flow in a sewage riser were carried out, in order to select the appropriate structure. The authors consider structure features of some sections of sewerage in high-rise buildings. The exhaustion value in the riser is determined from the rarefactions that occur below the compressed cross-section of the riser and the loss of the air flow pressure coming from the atmosphere into the riser during the deflooding of the liquid. Preventing the formation of obstructions and breakdowns of plumbing traps is an integral part of sewage networks.

  19. Investigation on Plasma Jet Flow Phenomena During DC Air Arc Motion in Bridge-Type Contacts

    Science.gov (United States)

    Zhai, Guofu; Bo, Kai; Chen, Mo; Zhou, Xue; Qiao, Xinlei

    2016-05-01

    Arc plasma jet flow in the air was investigated under a bridge-type contacts in a DC 270 V resistive circuit. We characterized the arc plasma jet flow appearance at different currents by using high-speed photography, and two polished contacts were used to search for the relationship between roughness and plasma jet flow. Then, to make the nature of arc plasma jet flow phenomena clear, a simplified model based on magnetohydrodynamic (MHD) theory was established and calculated. The simulated DC arc plasma was presented with the temperature distribution and the current density distribution. Furthermore, the calculated arc flow velocity field showed that the circular vortex was an embodiment of the arc plasma jet flow progress. The combined action of volume force and contact surface was the main reason of the arc jet flow. supported by National Natural Science Foundation of China (Nos. 51307030, 51277038)

  20. Cumulative exposure to shift work and sickness absence: associations in a five-year historic cohort.

    Science.gov (United States)

    van Drongelen, Alwin; Boot, Cécile R L; Hlobil, Hynek; van der Beek, Allard J; Smid, Tjabe

    2017-01-11

    Exposure to shift work has been associated with negative health consequences, although the association between shift work and sickness absence remains unclear. The aim of this study is to investigate associations between cumulative exposure to shift work and sickness absence among ground staff employees of an airline company. This study used data from the MORE (Monitoring Occupational Health Risks in Employees) cohort, which is a 5-year historic cohort. The population of the present study consisted of 7562 ground staff employees. For each employee, work schedules and sickness absence days between 2005 and 2009 were obtained from company records. For the exposure to different shift schedule types and to the cumulative number of night shifts, the association with long-term sickness absence (>7 consecutive sickness absence days) and the number of sickness absence episodes during 2009, was calculated using logistic and Poisson regression analyses. Socio-demographic variables, work-related variables, job classification variables, and previous sickness absence days were regarded as confounders. After adjusting for previous sickness absence and job classification variables, only the group of employees that switched into working in a three-shift schedule, showed a significantly increased risk for long-term sickness absence (OR = 1.31, 95%CI 1.02-1.69). Night shift exposure was not significantly associated with long-term sickness absence. Exposure to shift work was negatively associated with more sickness absence episodes. Employees who were exposed to more than 46 night shifts also showed a lower risk for more sickness absence episodes. Subgroup analyses showed that single employees and employees without children had an increased risk for long-term sickness absence when exposed to a three-shift schedule, and when they had changed between shift schedule types. Cumulative exposure to shift work proved to be negatively associated with more sickness absence episodes, and

  1. Cumulative exposure to shift work and sickness absence: associations in a five-year historic cohort

    Directory of Open Access Journals (Sweden)

    Alwin van Drongelen

    2017-01-01

    Full Text Available Abstract Background Exposure to shift work has been associated with negative health consequences, although the association between shift work and sickness absence remains unclear. The aim of this study is to investigate associations between cumulative exposure to shift work and sickness absence among ground staff employees of an airline company. Methods This study used data from the MORE (Monitoring Occupational Health Risks in Employees cohort, which is a 5-year historic cohort. The population of the present study consisted of 7562 ground staff employees. For each employee, work schedules and sickness absence days between 2005 and 2009 were obtained from company records. For the exposure to different shift schedule types and to the cumulative number of night shifts, the association with long-term sickness absence (>7 consecutive sickness absence days and the number of sickness absence episodes during 2009, was calculated using logistic and Poisson regression analyses. Socio-demographic variables, work-related variables, job classification variables, and previous sickness absence days were regarded as confounders. Results After adjusting for previous sickness absence and job classification variables, only the group of employees that switched into working in a three-shift schedule, showed a significantly increased risk for long-term sickness absence (OR = 1.31, 95%CI 1.02–1.69. Night shift exposure was not significantly associated with long-term sickness absence. Exposure to shift work was negatively associated with more sickness absence episodes. Employees who were exposed to more than 46 night shifts also showed a lower risk for more sickness absence episodes. Subgroup analyses showed that single employees and employees without children had an increased risk for long-term sickness absence when exposed to a three-shift schedule, and when they had changed between shift schedule types. Conclusions Cumulative exposure to shift work proved to

  2. Investigating the Relativistic Motion of the Stars Near the Supermassive Black Hole in the Galactic Center

    Energy Technology Data Exchange (ETDEWEB)

    Parsa, M.; Eckart, A.; Shahzamanian, B.; Zajaček, M.; Straubmeier, C. [I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, D-50937 Köln (Germany); Karas, V. [Astronomical Institute, Academy of Science, Boční II 1401, CZ-14131 Prague (Czech Republic); Zensus, J. A., E-mail: parsa@ph1.uni-koeln.de [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany)

    2017-08-10

    The S-star cluster in the Galactic center allows us to study the physics close to a supermassive black hole, including distinctive dynamical tests of general relativity. Our best estimates for the mass of and the distance to Sgr A* using the three stars with the shortest period (S2, S38, and S55/S0-102) and Newtonian models are M {sub BH} = (4.15 ± 0.13 ± 0.57) × 10{sup 6} M {sub ⊙} and R {sub 0} = 8.19 ± 0.11 ± 0.34 kpc. Additionally, we aim at a new and practical method to investigate the relativistic orbits of stars in the gravitational field near Sgr A*. We use a first-order post-Newtonian approximation to calculate the stellar orbits with a broad range of periapse distance r {sub p} . We present a method that employs the changes in orbital elements derived from elliptical fits to different sections of the orbit. These changes are correlated with the relativistic parameter defined as ϒ ≡ r {sub s} / r {sub p} (with r {sub s} being the Schwarzschild radius) and can be used to derive ϒ from observational data. For S2 we find a value of ϒ = 0.00088 ± 0.00080, which is consistent, within the uncertainty, with the expected value of ϒ = 0.00065 derived from M {sub BH} and the orbit of S2. We argue that the derived quantity is unlikely to be dominated by perturbing influences such as noise on the derived stellar positions, field rotation, and drifts in black hole mass.

  3. Dynamic Three-Dimensional Shoulder Mri during Active Motion for Investigation of Rotator Cuff Diseases.

    Directory of Open Access Journals (Sweden)

    Christine Tempelaere

    Full Text Available MRI is the standard methodology in diagnosis of rotator cuff diseases. However, many patients continue to have pain despite treatment, and MRI of a static unloaded shoulder seems insufficient for best diagnosis and treatment. This study evaluated if Dynamic MRI provides novel kinematic data that can be used to improve the understanding, diagnosis and best treatment of rotator cuff diseases.Dynamic MRI provided real-time 3D image series and was used to measure changes in the width of subacromial space, superior-inferior translation and anterior-posterior translation of the humeral head relative to the glenoid during active abduction. These measures were investigated for consistency with the rotator cuff diseases classifications from standard MRI.The study included: 4 shoulders with massive rotator cuff tears, 5 shoulders with an isolated full-thickness supraspinatus tear, 5 shoulders with tendinopathy and 6 normal shoulders. A change in the width of subacromial space greater than 4mm differentiated between rotator cuff diseases with tendon tears (massive cuff tears and supraspinatus tear and without tears (tendinopathy (p = 0.012. The range of the superior-inferior translation was higher in the massive cuff tears group (6.4mm than in normals (3.4mm (p = 0.02. The range of the anterior-posterior translation was higher in the massive cuff tears (9.2 mm and supraspinatus tear (9.3 mm shoulders compared to normals (3.5mm and tendinopathy (4.8mm shoulders (p = 0.05.The Dynamic MRI enabled a novel measure; 'Looseness', i.e. the translation of the humeral head on the glenoid during an abduction cycle. Looseness was better able at differentiating different forms of rotator cuff disease than a simple static measure of relative glenohumeral position.

  4. Development of a neural net paradigm that predicts simulator sickness

    Energy Technology Data Exchange (ETDEWEB)

    Allgood, G.O.

    1993-03-01

    A disease exists that affects pilots and aircrew members who use Navy Operational Flight Training Systems. This malady, commonly referred to as simulator sickness and whose symptomatology closely aligns with that of motion sickness, can compromise the use of these systems because of a reduced utilization factor, negative transfer of training, and reduction in combat readiness. A report is submitted that develops an artificial neural network (ANN) and behavioral model that predicts the onset and level of simulator sickness in the pilots and aircrews who sue these systems. It is proposed that the paradigm could be implemented in real time as a biofeedback monitor to reduce the risk to users of these systems. The model captures the neurophysiological impact of use (human-machine interaction) by developing a structure that maps the associative and nonassociative behavioral patterns (learned expectations) and vestibular (otolith and semicircular canals of the inner ear) and tactile interaction, derived from system acceleration profiles, onto an abstract space that predicts simulator sickness for a given training flight.

  5. Sickness absence: a systematic review and meta-analysis of psychological treatments for individuals on sick leave due to common mental disorders.

    Science.gov (United States)

    Salomonsson, Sigrid; Hedman-Lagerlöf, Erik; Öst, Lars-Göran

    2018-01-30

    Sick leave due to common mental disorders (CMDs) increase rapidly and present a major societal challenge. The overall effect of psychological interventions to reduce sick leave and symptoms has not been sufficiently investigated and there is a need for a systematic review and meta-analysis of the field. The aim of the present meta-analysis was to calculate the effect size of psychological interventions for CMDs on sick leave and psychiatric symptoms based on all published randomized controlled trials. Methodological quality, the risk of bias and publication bias were also assessed. The literature searches gave 2240 hits and 45 studies were included. The psychological interventions were more effective than care as usual on both reduced sick leave (g = 0.15) and symptoms (g = 0.21). There was no significant difference in effect between work focused interventions, problem-solving therapy, cognitive behavioural therapy or collaborative care. We conclude that psychological interventions are more effective than care as usual to reduce sick leave and symptoms but the effect sizes are small. More research is needed on psychological interventions that evaluate effects on sick leave. Consensual measures of sick leave should be established and quality of psychotherapy for patients on sick leave should be improved.

  6. Long Sick Leave after Orthopaedic Inpatient Rehabilitation: Treatment Failure or Relapse?

    Science.gov (United States)

    Mangels, Marija; Schwarz, Susanne; Worringen, Ulrike; Holme, Martin; Rief, Winfried

    2011-01-01

    We investigated whether short-term versus long-term sick leave after orthopaedic inpatient rehabilitation can be predicted by initial assessment information, the clinical status at discharge, or whether the follow-up interval is crucial for later sick leave. We examined 214 patients from an orthopaedic rehabilitation hospital at admission,…

  7. Employees Sick-Listed with Mental Disorders : Who Returns to Work and When?

    NARCIS (Netherlands)

    Roelen, C. A. M.; Norder, G.; Koopmans, P. C.; van Rhenen, W.; van der Klink, J. J. L.; Bultmann, U.

    Purpose To investigate return to work (RTW) in employees sick-listed with mental disorders classified according to the International Classification of Diseases (ICD). Methods Sickness absences (SA) medically certified as emotional disturbance (ICD-10 R45) or mental and behavioral disorders (ICD-10

  8. Transitions between sickness absence, work, unemployment, and disability in Denmark 2004-2008

    DEFF Research Database (Denmark)

    Pedersen, Jacob; Bjørner, Jakob; Burr, Hermann

    2012-01-01

    Studies of labor market outcomes like sickness absence are usually restricted to a single outcome. This paper investigates the use of multi-state models for studying multiple transitions between sick-listing, work, unemployment, and disability pension by analyzing longitudinal register data. Every...

  9. Severe occupational hand eczema, job stress and cumulative sickness absence.

    Science.gov (United States)

    Böhm, D; Stock Gissendanner, S; Finkeldey, F; John, S M; Werfel, T; Diepgen, T L; Breuer, K

    2014-10-01

    Stress is known to activate or exacerbate dermatoses, but the relationships between chronic stress, job-related stress and sickness absence among occupational hand eczema (OHE) patients are inadequately understood. To see whether chronic stress or burnout symptoms were associated with cumulative sickness absence in patients with OHE and to determine which factors predicted sickness absence in a model including measures of job-related and chronic stress. We investigated correlations of these factors in employed adult inpatients with a history of sickness absence due to OHE in a retrospective cross-sectional explorative study, which assessed chronic stress (Trier Inventory for the Assessment of Chronic Stress), burnout (Shirom Melamed Burnout Measure), clinical symptom severity (Osnabrück Hand Eczema Severity Index), perceived symptom severity, demographic characteristics and cumulative days of sickness absence. The study group consisted of 122 patients. OHE symptoms were not more severe among patients experiencing greater stress and burnout. Women reported higher levels of chronic stress on some measures. Cumulative days of sickness absence correlated with individual dimensions of job-related stress and, in multiple regression analysis, with an overall measure of chronic stress. Chronic stress is an additional factor predicting cumulative sickness absence among severely affected OHE patients. Other relevant factors for this study sample included the 'cognitive weariness' subscale of the Shirom Melamed Burnout Measure and the physical component summary score of the SF-36, a measure of health-related life quality. Prevention and rehabilitation should take job stress into consideration in multidisciplinary treatment strategies for severely affected OHE patients. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. An analytical investigation on unsteady motion of vertically falling spherical particles in non-Newtonian fluid by Collocation Method

    Directory of Open Access Journals (Sweden)

    M. Rahimi-Gorji

    2015-06-01

    Full Text Available An analytical investigation is applied for unsteady motion of a rigid spherical particle in a quiescent shear-thinning power-law fluid. The results were compared with those obtained from Collocation Method (CM and the established Numerical Method (Fourth order Runge–Kutta scheme. It was shown that CM gave accurate results. Collocation Method (CM and Numerical Method are used to solve the present problem. We obtained that the CM which was used to solve such nonlinear differential equation with fractional power is simpler and more accurate than series method such as HPM which was used in some previous works by others but the new method named Akbari-Ganji’s Method (AGM is an accurate and simple method which is slower than CM for solving such problems. The terminal settling velocity—that is the velocity at which the net forces on a falling particle eliminate—for three different spherical particles (made of plastic, glass and steel and three flow behavior index n, in three sets of power-law non-Newtonian fluids was investigated, based on polynomial solution (CM. Analytical results obtained indicated that the time of reaching the terminal velocity in a falling procedure is significantly increased with growing of the particle size that validated with Numerical Method. Further, with approaching flow behavior to Newtonian behavior from shear-thinning properties of flow (n → 1, the transient time to achieving the terminal settling velocity is decreased.

  11. Sleeping Sickness Surveillance In The Abraka Sleeping Sickness ...

    African Journals Online (AJOL)

    Confirmation of sleeping sickness (ss) was by the detection of trypanosomes in blood, body fluids and biopsy tissues. Thirteen (0.8%) seropositive subjects were parasitologically confirmed and treated with melasoprol at the Baptist Medical Centre (BMC) Eku. One (0.06%) patient died during the course of treatment.

  12. Sickness absence among municipal workers in a Brazilian municipality: a secondary data analysis.

    Science.gov (United States)

    Leao, Ana Lucia M; Barbosa-Branco, Anadergh; Turchi, Marília D; Steenstra, Ivan A; Cole, Donald C

    2017-12-28

    Sickness absence, work disability associated with illness or injury, is a major public health problem worldwide. Some studies have investigated determinants of sickness absence among workers with shorter job tenure, but have only focused on certain diagnostic groups. Although it is well established that job tenure has an inverse relationship with work injury rate, less is known about its association with sickness absence for other disorders. Therefore, this study aimed to investigate the risk factors for incidence and duration of sickness absence according to diagnosis over a 7-year period. A dynamic cohort consisting of all permanent civil servants hired from 2005 to 2011 by the Goiania municipality-Brazil. Data of certified sickness absences longer than 3 days were analyzed. The incidence density was calculated per 1000 person-years in each ICD-10 category. The association between sickness absence and socio-demographic and occupational characteristics was examined using negative binomial regression models. 18,450 workers, mean age of 32 years, accumulated 14,909 episodes of sickness absence. Overall, the incidence density was 234.6 episodes per 1000 person years. Diagnostic groups with the highest incidence density of sickness absences were injuries (49.1), musculoskeletal disorders (31.3) and mental disorders (29.2). Factors predicting any sickness absence were female gender, older age, low education, being a health professional, multiple jobs and full-time employment. Mental health disorders were more common among education professionals, musculoskeletal disorders among blue collar workers and injuries among inspection workers. Prolonged time on sick leave was associated with male gender, older age groups, low education and income, blue-collar workers, more than one job contract and full time employment. These findings demonstrate a substantial sickness absentee burden and they provide relevant information for targeting prevention and health promotion

  13. SICKNESS PRESENCE AND STRESSFUL LIFE EVENTS OF HEALTH CARE WORKERS.

    Science.gov (United States)

    Škerjanc, Alenka; Fikfak, Metoda Dodič

    2015-09-01

    The aim of the study is to investigate the relationship between sickness presence and stressful life events among health care workers. Data were gathered from all health care workers at the University Medical Centre Ljubljana employed there in the period between 1 January 2010 and 31 December 2010. Each employee obtained a questionnaire composed of two standardized international questionnaires. There were 57% of sickness present health care workers among the participants. The sickness present reported to have more diseases of family member than the non-sickness present (OR = 1.5; 95% CI = 1.2-2.0), loan (OR = 1.4; 95% CI = 1.1-1.6), their partner lost job (OR = 1.4; 95% CI = 1.0-1.8), or they changed the place of living (OR = 1.4; 95% CI = 1.0-2.0). The results of the study indicate that stressful life events with economic consequences might have an important influence on sickness presence.

  14. The associations between workplace bullying, salivary cortisol, and long-term sickness absence

    DEFF Research Database (Denmark)

    Grynderup, Matias Brødsgaard; Nabe-Nielsen, Kirsten; Lange, Theis

    2017-01-01

    two Danish cohort studies, the "Psychosocial RIsk factors for Stress and MEntal disease" (PRISME) cohort and the "Workplace Bullying and Harassment" (WBH) cohort (n = 5418). Information about exposure to workplace bullying and morning and evening salivary cortisol was collected at three time points......BACKGROUND: Workplace stressors, such as bullying, are strongly related to subsequent long-term sickness absence, but little is known of the possible physiological mechanisms linking workplace stressors and sickness absence. The primary aim of this study was to investigate to what extent cortisol...... levels were associated with subsequent sickness absence and if cortisol mediated the association between workplace bullying and sickness absence. We additionally investigated possible bidirectional associations between bullying, cortisol, and long-term sickness absence. METHODS: Participants came from...

  15. Investigating the effect of poly-l-lactic acid nanoparticles carrying hypericin on the flow-biased diffusive motion of HeLa cell organelles.

    Science.gov (United States)

    Penjweini, Rozhin; Deville, Sarah; Haji Maghsoudi, Omid; Notelaers, Kristof; Ethirajan, Anitha; Ameloot, Marcel

    2017-07-19

    In this study, we investigate in human cervical epithelial HeLa cells the intracellular dynamics and the mutual interaction with the organelles of the poly-l-lactic acid nanoparticles (PLLA NPs) carrying the naturally occurring hydrophobic photosensitizer hypericin. Temporal and spatiotemporal image correlation spectroscopy was used for the assessment of the intracellular diffusion and directed motion of the nanocarriers by tracking the hypericin fluorescence. Using image cross-correlation spectroscopy and specific fluorescent labelling of endosomes, lysosomes and mitochondria, the NPs dynamics in association with the cell organelles was studied. Static colocalization experiments were interpreted according to the Manders' overlap coefficient. Nanoparticles associate with a small fraction of the whole-organelle population. The organelles moving with NPs exhibit higher directed motion compared to those moving without them. The rate of the directed motion drops substantially after the application of nocodazole. The random component of the organelle motions is not influenced by the NPs. Image correlation and cross-correlation spectroscopy are most appropriate to unravel the motion of the PLLA nanocarrier and to demonstrate that the rate of the directed motion of organelles is influenced by their interaction with the nanocarriers. Not all PLLA-hypericin NPs are associated with organelles. © 2017 Royal Pharmaceutical Society.

  16. Numerical investigation of fluid mud motion using a three-dimensional hydrodynamic and two-dimensional fluid mud coupling model

    Science.gov (United States)

    Yang, Xiaochen; Zhang, Qinghe; Hao, Linnan

    2015-03-01

    A water-fluid mud coupling model is developed based on the unstructured grid finite volume coastal ocean model (FVCOM) to investigate the fluid mud motion. The hydrodynamics and sediment transport of the overlying water column are solved using the original three-dimensional ocean model. A horizontal two-dimensional fluid mud model is integrated into the FVCOM model to simulate the underlying fluid mud flow. The fluid mud interacts with the water column through the sediment flux, current, and shear stress. The friction factor between the fluid mud and the bed, which is traditionally determined empirically, is derived with the assumption that the vertical distribution of shear stress below the yield surface of fluid mud is identical to that of uniform laminar flow of Newtonian fluid in the open channel. The model is validated by experimental data and reasonable agreement is found. Compared with numerical cases with fixed friction factors, the results simulated with the derived friction factor exhibit the best agreement with the experiment, which demonstrates the necessity of the derivation of the friction factor.

  17. Mood, anxiety, and alcohol use disorders and later cause-specific sick leave in young adult employees

    Directory of Open Access Journals (Sweden)

    Fartein Ask Torvik

    2016-08-01

    Full Text Available Abstract Background Mental disorders strongly influence work capability in young adults, but it is not clear which disorders that are most strongly associated with sick leave, and which diagnoses that are stated on the sick leave certificates. Better knowledge of the impairments associated with different mental disorders is needed for optimal planning of interventions and prioritization of health services. In the current study, we investigate the prospective associations between eight mood, anxiety, and alcohol use disorders, and later sick leave granted for mental, somatic, or any disorder. Methods Lifetime mental disorders were assessed by structured diagnostic interviews in 2,178 young adults followed for eight years with registry data on sick leave. Relative risk ratios were estimated for the associations between each mental disorder and the different forms of sick leave. Results All included diagnoses were associated with later sick leave. In adjusted analyses, major depressive disorder and generalized anxiety disorder were the strongest predictors of sick leave granted for mental disorders, whereas social anxiety disorder and specific phobia were the strongest predictors of sick leave granted for somatic disorders. Specific phobia and major depressive disorder had the highest attributable fractions for all-cause sick leave. Conclusions Mood and anxiety disorders constituted independent risk factors for all cause sick leave, whereas alcohol use disorders seemed to be of less importance in young adulthood. Disorders characterised by distress were most strongly associated with sick leave granted for mental disorders, whereas disorders characterised by fear primarily predicted sick leave granted for somatic conditions. A large part of all sick leave is related to specific phobia, due to the high prevalence of this disorder. The impairment associated with this common disorder may be under-acknowledged, and it could decrease work capacity among

  18. Mood, anxiety, and alcohol use disorders and later cause-specific sick leave in young adult employees.

    Science.gov (United States)

    Torvik, Fartein Ask; Reichborn-Kjennerud, Ted; Gjerde, Line C; Knudsen, Gun Peggy; Ystrom, Eivind; Tambs, Kristian; Røysamb, Espen; Østby, Kristian; Ørstavik, Ragnhild

    2016-08-03

    Mental disorders strongly influence work capability in young adults, but it is not clear which disorders that are most strongly associated with sick leave, and which diagnoses that are stated on the sick leave certificates. Better knowledge of the impairments associated with different mental disorders is needed for optimal planning of interventions and prioritization of health services. In the current study, we investigate the prospective associations between eight mood, anxiety, and alcohol use disorders, and later sick leave granted for mental, somatic, or any disorder. Lifetime mental disorders were assessed by structured diagnostic interviews in 2,178 young adults followed for eight years with registry data on sick leave. Relative risk ratios were estimated for the associations between each mental disorder and the different forms of sick leave. All included diagnoses were associated with later sick leave. In adjusted analyses, major depressive disorder and generalized anxiety disorder were the strongest predictors of sick leave granted for mental disorders, whereas social anxiety disorder and specific phobia were the strongest predictors of sick leave granted for somatic disorders. Specific phobia and major depressive disorder had the highest attributable fractions for all-cause sick leave. Mood and anxiety disorders constituted independent risk factors for all cause sick leave, whereas alcohol use disorders seemed to be of less importance in young adulthood. Disorders characterised by distress were most strongly associated with sick leave granted for mental disorders, whereas disorders characterised by fear primarily predicted sick leave granted for somatic conditions. A large part of all sick leave is related to specific phobia, due to the high prevalence of this disorder. The impairment associated with this common disorder may be under-acknowledged, and it could decrease work capacity among individuals with somatic disorders. This disorder has good treatment

  19. SU-E-J-197: Investigation of Microsoft Kinect 2.0 Depth Resolution for Patient Motion Tracking

    Energy Technology Data Exchange (ETDEWEB)

    Silverstein, E; Snyder, M [Wayne State University, Detroit, MI (United States)

    2015-06-15

    Purpose: Investigate the use of the Kinect 2.0 for patient motion tracking during radiotherapy by studying spatial and depth resolution capabilities. Methods: Using code written in C#, depth map data was abstracted from the Kinect to create an initial depth map template indicative of the initial position of an object to be compared to the depth map of the object over time. To test this process, simple setup was created in which two objects were imaged: a 40 cm × 40 cm board covered in non reflective material and a 15 cm × 26 cm textbook with a slightly reflective, glossy cover. Each object, imaged and measured separately, was placed on a movable platform with object to camera distance measured. The object was then moved a specified amount to ascertain whether the Kinect’s depth camera would visualize the difference in position of the object. Results: Initial investigations have shown the Kinect depth resolution is dependent on the object to camera distance. Measurements indicate that movements as small as 1 mm can be visualized for objects as close as 50 cm away. This depth resolution decreases linearly with object to camera distance. At 4 m, the depth resolution had decreased to observe a minimum movement of 1 cm. Conclusion: The improved resolution and advanced hardware of the Kinect 2.0 allows for increase of depth resolution over the Kinect 1.0. Although obvious that the depth resolution should decrease with increasing distance from an object given the decrease in number of pixels representing said object, the depth resolution at large distances indicates its usefulness in a clinical setting.

  20. LROC Investigation of Three Strategies for Reducing the Impact of Respiratory Motion on the Detection of Solitary Pulmonary Nodules in SPECT

    Science.gov (United States)

    Smyczynski, Mark S.; Gifford, Howard C.; Dey, Joyoni; Lehovich, Andre; McNamara, Joseph E.; Segars, W. Paul; King, Michael A.

    2016-02-01

    The objective of this investigation was to determine the effectiveness of three motion reducing strategies in diminishing the degrading impact of respiratory motion on the detection of small solitary pulmonary nodules (SPNs) in single-photon emission computed tomographic (SPECT) imaging in comparison to a standard clinical acquisition and the ideal case of imaging in the absence of respiratory motion. To do this nonuniform rational B-spline cardiac-torso (NCAT) phantoms based on human-volunteer CT studies were generated spanning the respiratory cycle for a normal background distribution of Tc-99 m NeoTect. Similarly, spherical phantoms of 1.0-cm diameter were generated to model small SPN for each of the 150 uniquely located sites within the lungs whose respiratory motion was based on the motion of normal structures in the volunteer CT studies. The SIMIND Monte Carlo program was used to produce SPECT projection data from these. Normal and single-lesion containing SPECT projection sets with a clinically realistic Poisson noise level were created for the cases of 1) the end-expiration (EE) frame with all counts, 2) respiration-averaged motion with all counts, 3) one fourth of the 32 frames centered around EE (Quarter Binning), 4) one half of the 32 frames centered around EE (Half Binning), and 5) eight temporally binned frames spanning the respiratory cycle. Each of the sets of combined projection data were reconstructed with RBI-EM with system spatial-resolution compensation (RC). Based on the known motion for each of the 150 different lesions, the reconstructed volumes of respiratory bins were shifted so as to superimpose the locations of the SPN onto that in the first bin (Reconstruct and Shift). Five human observers performed localization receiver operating characteristics (LROC) studies of SPN detection. The observer results were analyzed for statistical significance differences in SPN detection accuracy among the three correction strategies, the standard

  1. Experimental investigation of the sloshing motion of the water free surface in the draft tube of a Francis turbine operating in synchronous condenser mode

    Science.gov (United States)

    Vagnoni, Elena; Favrel, Arthur; Andolfatto, Loïc; Avellan, François

    2018-06-01

    Hydropower units may be required to operate in condenser mode to supply reactive power. In this operating mode, the water level in the turbine or pump-turbine is decreased below the runner by closing the guide vanes and injecting pressurized air. While operating in condenser mode the machine experiences power losses due to several air-water interaction phenomena which cause air losses. One of such phenomena is the sloshing motion of the water free surface below the runner in the draft tube cone of a Francis turbine. The objective of the present work is to experimentally investigate the sloshing motion of the water free surface in the draft tube cone of a reduced scale physical model of a Francis turbine operating in condenser mode. Images acquisition and simultaneous pressure fluctuation measurements are performed and an image processing method is developed to investigate amplitude and frequency of the sloshing motion of the free surface. It is found that this motion is excited at the natural frequency of the water volume and corresponds to the azimuthal wavenumber m = 1 of a rotating gravity wave. The amplitude of the motion is perturbed by wave breaking and it decreases by increasing the densimetric Froude number. The sloshing frequency slightly increases with respect to the natural frequency of the water volume by increasing the densimetric Froude number. Moreover, it results that this resonant phenomenon is not related to the torque perturbation.

  2. Dose-response relation between physical activity and sick leave

    NARCIS (Netherlands)

    Proper, K.I.; Heuvel, S.G. van den; Vroome, E.M. de; Hildebrandt, V.H.; Beek, A.J. van der

    2006-01-01

    Objective: To investigate the dose-response relation between moderate and vigorous physical activity and sick leave in a working population. Methods: Data were used from three large Dutch databases: two continuous, cross sectional surveys among a representative sample of the Dutch population and one

  3. Improving the effectiveness of sickness benefit case management through a public-private partnership?

    DEFF Research Database (Denmark)

    Larsen, Malene Rode; Aust, Birgit; Høgelund, Jan

    2017-01-01

    Background The aim of this study was to investigate whether a multidimensional public-private partnership intervention, focussing on improving the quality and efficiency of sickness benefit case management, reduced the sickness benefit duration and the duration until self-support. Methods We used...... a difference-in-difference (DID) design with six intervention municipalities and 12 matched control municipalities in Denmark. The study sample comprised 282,103 sickness benefit spells exceeding four weeks. The intervention group with 110,291 spells received the intervention, and the control group with 171......,812 spells received ordinary sickness benefit case management. Using register data, we fitted Cox proportional hazard ratio models, estimating hazard ratios (HR) and confidence intervals (CI). Results We found no joint effect of the intervention on the sickness benefit duration (HR 1.02, CI 0...

  4. Investigation of the 4D composite MR image distortion field associated with tumor motion for MR-guided radiotherapy.

    Science.gov (United States)

    Stanescu, T; Jaffray, D

    2016-03-01

    Magnetic resonance (MR) images are affected by geometric distortions due to the specifics of the MR scanner and patient anatomy. Quantifying the distortions associated with mobile tumors is particularly challenging due to real anatomical changes in the tumor's volume, shape, and relative location within the MR imaging volume. In this study, the authors investigate the 4D composite distortion field, which combines the effects of the susceptibility-induced and system-related distortion fields, experienced by mobile lung tumors. The susceptibility (χ) effects were numerically simulated for two specific scenarios: (a) a full motion cycle of a lung tumor due to breathing as depicted on ten phases of a 4D CBCT data set and (b) varying the tumor size and location in lung tissue via a synthetically generated sphere with variable diameter (4-80 mm). The χ simulation procedure relied on the segmentation and generation of 3D susceptibility (χ) masks and computation of the magnetic field by means of finite difference methods. A system-related distortion field, determined with a phantom and image processing algorithm, was used as a reference. The 4D composite distortion field was generated as the vector summation of the χ-induced and system-related fields. The analysis was performed for two orientations of the main magnetic field (B0), which correspond to several MRIgRT system configurations. Specifically, B0 was set along the z-axis as in the case of a cylindrical-bore scanner and in the (x,y)-plane as for a biplanar MR. Computations were also performed for a full revolution at 15° increments in the case of a rotating biplanar magnet. Histograms and metrics such as maximum, mean, and range were used to evaluate the characteristics of the 4D distortion field. The χ-induced field depends on the change in volume and shape of the moving tumor as well as the local surrounding anatomy. In the case of system-related distortions, the tumor experiences increased field

  5. Experimental and Simulation-Based Investigation of Polycentric Motion of an Inherent Compliant Pneumatic Bending Actuator with Skewed Rotary Elastic Chambers

    Directory of Open Access Journals (Sweden)

    André Wilkening

    2017-01-01

    Full Text Available To offer a functionality that could not be found in traditional rigid robots, compliant actuators are in development worldwide for a variety of applications and especially for human–robot interaction. Pneumatic bending actuators are a special kind of such actuators. Due to the absence of fixed mechanical axes and their soft behavior, these actuators generally possess a polycentric motion ability. This can be very useful to provide an implicit self-alignment to human joint axes in exoskeleton-like rehabilitation devices. As a possible realization, a novel bending actuator (BA was developed using patented pneumatic skewed rotary elastic chambers (sREC. To analyze the actuator self-alignment properties, knowledge about the motion of this bending actuator type, the so-called skewed rotary elastic chambers bending actuator (sRECBA, is of high interest and this paper presents experimental and simulation-based kinematic investigations. First, to describe actuator motion, the finite helical axes (FHA of basic actuator elements are determined using a three-dimensional (3D camera system. Afterwards, a simplified two-dimensional (2D kinematic simulation model based on a four-bar linkage was developed and the motion was compared to the experimental data by calculating the instantaneous center of rotation (ICR. The equivalent kinematic model of the sRECBA was realized using a series of four-bar linkages and the resulting ICR was analyzed in simulation. Finally, the FHA of the sRECBA were determined and analyzed for three different specific motions. The results show that the actuator’s FHA adapt to different motions performed and it can be assumed that implicit self-alignment to the polycentric motion of the human joint axis will be provided.

  6. Predictors of recurrent sickness absence among workers having returned to work after sickness absence due to common mental disorders

    NARCIS (Netherlands)

    Arends, I.; van der Klink, J.J.L.; van Rhenen, W.; de Boer, M.R.; Bultmann, U.

    2014-01-01

    Objective The aim of this study was to investigate whether sociodemographic, disease-related, personal, and work-related factors - measured at baseline - are predictors of recurrent sickness absence (SA) at 6 and 12 months follow-up among workers who returned to work after SA due to common mental

  7. Predictors of recurrent sickness absence among workers having returned to work after sickness absence due to common mental disorders

    NARCIS (Netherlands)

    Arends, Iris; van der Klink, Jac J. L.; van Rhenen, Willem; de Boer, Michiel R.; Bultmann, Ute

    Objective The aim of this study was to investigate whether sociodemographic, disease-related, personal, and work-related factors - measured at baseline - are predictors of recurrent sickness absence (SA) at 6 and 12 months follow-up among workers who returned to work after SA due to common mental

  8. The consequences of sickness presenteeism on health and wellbeing over time: A systematic review.

    Science.gov (United States)

    Skagen, Kristian; Collins, Alison M

    2016-07-01

    The association between sickness presenteeism, defined as going to work despite illness, and different health outcomes is increasingly being recognized as a significant and relevant area of research. However, the long term effects on future employee health are less well understood, and to date there has been no review of the empirical evidence. The aim of this systematic review was to present a summary of the sickness presenteeism evidence so far in relation to health and wellbeing over time. Eight databases were searched for longitudinal studies that investigated the consequences of workplace sickness presenteeism, had a baseline and at least one follow-up point, and included at least one specific measure of sickness presenteeism. Of the 453 papers identified, 12 studies met the eligibility criteria and were included in the review. We adopted a thematic approach to the analysis because of the heterogeneous nature of the sickness presenteeism research. The majority of studies found that sickness presenteeism at baseline is a risk factor for future sickness absence and decreased self-rated health. However, our findings highlight that a consensus has not yet been reached in terms of physical and mental health. This is because the longitudinal studies included in this review adopt a wide variety of approaches including the definition of sickness presenteeism, recall periods, measures used and different statistical approaches which is problematic if this research area is to advance. Future research directions are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. The associations between workplace bullying, salivary cortisol, and long-term sickness absence: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Matias Brødsgaard Grynderup

    2017-09-01

    Full Text Available Abstract Background Workplace stressors, such as bullying, are strongly related to subsequent long-term sickness absence, but little is known of the possible physiological mechanisms linking workplace stressors and sickness absence. The primary aim of this study was to investigate to what extent cortisol levels were associated with subsequent sickness absence and if cortisol mediated the association between workplace bullying and sickness absence. We additionally investigated possible bidirectional associations between bullying, cortisol, and long-term sickness absence. Methods Participants came from two Danish cohort studies, the “Psychosocial RIsk factors for Stress and MEntal disease” (PRISME cohort and the “Workplace Bullying and Harassment” (WBH cohort (n = 5418. Information about exposure to workplace bullying and morning and evening salivary cortisol was collected at three time points with approximately two years in between. After each data collection, all participants were followed for two years in registers, and cases with long-term sickness absence lasting 30 or more consecutive days were identified. The association between cortisol levels and subsequent sickness absence was assessed by logistic regression, while the extent to which the association between bullying and sickness absence was mediated by cortisol was quantified through natural direct and indirect effects. Results High evening cortisol was associated with a decreased risk of sickness absence (OR = 0.82, 95% CI = 0.68–0.99, but we did not find that high morning cortisol levels (OR = 0.98, 95% CI = 0.81–1.18 or high morning-to-evening slope (OR = 0.99, 95% CI = 0.82–1.18 were associated with subsequent sickness absence. We also tested for reverse causation and found that long-term sickness absence, but not salivary cortisol, was a strong risk factor for subsequent workplace bullying. There was no indication that cortisol mediated the association

  10. The associations between workplace bullying, salivary cortisol, and long-term sickness absence: a longitudinal study.

    Science.gov (United States)

    Grynderup, Matias Brødsgaard; Nabe-Nielsen, Kirsten; Lange, Theis; Conway, Paul Maurice; Bonde, Jens Peter; Garde, Anne Helene; Gullander, Maria; Kaerlev, Linda; Persson, Roger; Rugulies, Reiner; Vammen, Marianne Agergaard; Høgh, Annie; Hansen, Åse Marie

    2017-09-16

    Workplace stressors, such as bullying, are strongly related to subsequent long-term sickness absence, but little is known of the possible physiological mechanisms linking workplace stressors and sickness absence. The primary aim of this study was to investigate to what extent cortisol levels were associated with subsequent sickness absence and if cortisol mediated the association between workplace bullying and sickness absence. We additionally investigated possible bidirectional associations between bullying, cortisol, and long-term sickness absence. Participants came from two Danish cohort studies, the "Psychosocial RIsk factors for Stress and MEntal disease" (PRISME) cohort and the "Workplace Bullying and Harassment" (WBH) cohort (n = 5418). Information about exposure to workplace bullying and morning and evening salivary cortisol was collected at three time points with approximately two years in between. After each data collection, all participants were followed for two years in registers, and cases with long-term sickness absence lasting 30 or more consecutive days were identified. The association between cortisol levels and subsequent sickness absence was assessed by logistic regression, while the extent to which the association between bullying and sickness absence was mediated by cortisol was quantified through natural direct and indirect effects. High evening cortisol was associated with a decreased risk of sickness absence (OR = 0.82, 95% CI = 0.68-0.99), but we did not find that high morning cortisol levels (OR = 0.98, 95% CI = 0.81-1.18) or high morning-to-evening slope (OR = 0.99, 95% CI = 0.82-1.18) were associated with subsequent sickness absence. We also tested for reverse causation and found that long-term sickness absence, but not salivary cortisol, was a strong risk factor for subsequent workplace bullying. There was no indication that cortisol mediated the association between workplace bullying and sickness absence. We found no

  11. Sickness Absence and Precarious Employment: A Comparative Cross-National Study of Denmark, Finland, Sweden, and Norway

    Directory of Open Access Journals (Sweden)

    A Oke

    2016-07-01

    Full Text Available Background: Precarious employment is a major social determinant of health and health inequalities with effects beyond the health of workers. Objective: To investigate the association between precarious employment and sickness absence in 4 Nordic countries, Denmark, Finland, Norway, and Sweden. Methods: Logistic regression analyses were conducted separately for each country on data from 4186 respondents aged 15–65 years in Denmark, Finland, Norway, and Sweden derived from the 2010 European Working Conditions Survey. Sickness absence was based on self-reports and defined as absence of seven or more day per year. Precarious employment was operationalized as a multidimensional construct of indicators. Analyses were also conducted separately for men and women. Results: The prevalence of sickness absence was lowest in Sweden (18%, and highest in Finland (28%. 3 precarious employment indicators were positively associated with sickness absence; the pattern being largely similar in the total sample. In the sex-disaggregated sample, 5 precarious employment indicators increased the likelihood of sickness absence; the pattern was heterogeneous, with women generally having significantly higher odds of sickness absence than men. “Low household income” and “sickness presenteeism” were strong predictors of sickness absence among both sexes in most of the 4 studied countries. Sickness absence varied between the Nordic countries in the sex-disaggregated analyses. Conclusion: Precarious employment indicators predicted sickness absence in the Nordic countries. Findings emphasize the need to prioritize informed and monitored collective bargaining for all workers, increase working time flexibility, and improving work conditions.

  12. Sickness Absence and Precarious Employment: A Comparative Cross-National Study of Denmark, Finland, Sweden, and Norway.

    Science.gov (United States)

    Oke, A; Braithwaite, P; Antai, D

    2016-07-01

    Precarious employment is a major social determinant of health and health inequalities with effects beyond the health of workers. To investigate the association between precarious employment and sickness absence in 4 Nordic countries, Denmark, Finland, Norway, and Sweden. Logistic regression analyses were conducted separately for each country on data from 4186 respondents aged 15-65 years in Denmark, Finland, Norway, and Sweden derived from the 2010 European Working Conditions Survey. Sickness absence was based on self-reports and defined as absence of seven or more day per year. Precarious employment was operationalized as a multidimensional construct of indicators. Analyses were also conducted separately for men and women. The prevalence of sickness absence was lowest in Sweden (18%), and highest in Finland (28%). 3 precarious employment indicators were positively associated with sickness absence; the pattern being largely similar in the total sample. In the sex-disaggregated sample, 5 precarious employment indicators increased the likelihood of sickness absence; the pattern was heterogeneous, with women generally having significantly higher odds of sickness absence than men. "Low household income" and "sickness presenteeism" were strong predictors of sickness absence among both sexes in most of the 4 studied countries. Sickness absence varied between the Nordic countries in the sex-disaggregated analyses. Precarious employment indicators predicted sickness absence in the Nordic countries. Findings emphasize the need to prioritize informed and monitored collective bargaining for all workers, increase working time flexibility, and improving work conditions.

  13. Changes in the dark focus of accommodation associated with simulator sickness

    Science.gov (United States)

    Fowlkes, Jennifer E.; Kennedy, Robert S.; Hettinger, Lawrence J.; Harm, Deborah L.

    1993-01-01

    The relationship between the dark focus of accommodation and simulator sickness, a form of motion sickness, was examined in three experiments. In Experiment 1, dark focus was measured in 18 college students in a laboratory setting before and after they viewed a projected motion scene depicting low altitude helicopter flight. In Experiments 2 and 3, dark focus was measured in pilots (N = 16 and 23, respectively) before and after they 'flew' in moving-base helicopter flight simulators with optical infinity CRT visual systems. The results showed that individuals who experienced simulator sickness had either an inward (myopic) change in dark focus (Experiments 1 and 3) or attenuated outward shifts in dark focus (Experiment 2) relative to participants who did not get sick. These results are consonant with the hypothesis that parasympathetic activity, which may be associated with simulator sickness, should result in changes in dark focus that are in a myopic direction. Night vision goggles, virtual environments, extended periods in microgravity, and heads-up displays all produce related visual symptomatology. Changes in dark focus may occur in these conditions, as well, and should be measured.

  14. The use of adaptation to reduce simulator sickness in driving assessment and research.

    Science.gov (United States)

    Domeyer, Joshua E; Cassavaugh, Nicholas D; Backs, Richard W

    2013-04-01

    The technical advancement of driving simulators has decreased their cost and increased both their accuracy and fidelity. This makes them a useful tool for examining driving behavior in risky or unique situations. With the approaching increase of older licensed drivers due to aging of the baby boomers, driving simulators will be important for conducting driving research and evaluations for older adults. With these simulator technologies, some people may experience significant effects of a unique form of motion sickness, known as simulator sickness. These effects may be more pronounced in older adults. The present study examined the feasibility of an intervention to attenuate symptoms of simulator sickness in drivers participating in a study of a driving evaluation protocol. Prior to beginning the experiment, the experimental groups did not differ in subjective simulator sickness scores as indicated by Revised Simulator Sickness Questionnaire scores (all p>0.5). Participants who experienced a two-day delay between an initial acclimation to the driving simulator and the driving session experienced fewer simulator sickness symptoms as indicated by RSSQ total severity scores than participants who did not receive a two-day delay (F(1,88)=4.54, p=.036, partial η(2)=.049). These findings have implications for improving client well-being and potentially increasing acceptance of driving simulation for driving evaluations and for driving safety research. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Tight or sick building syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Thirumalaikolundusubramanian, P; Shanmuganadan, S [Madurai Kamaraj Univ. (India). Dept. of Geography; Uma, A [Madurai Medical Coll. (India). Dept. of Medicine and Microbiology

    1991-01-01

    Modern buildings are designed with the usual heating, air-conditioning and ventilation equipment. In most of these buildings, air is continuously recirculated and, as a result, workers suffer from tight or sick building syndrome. This syndrome is discussed with reference to symptoms of air contamination, ventilation system standards and research needs. The most common symptoms of tight building syndrome are eye, nose and throat irritation, headache, fatigue, sneezing, difficulty in wearing contact lenses, chest tightness, nausea, dizziness and dermatitis. Symptoms experienced by 50 doctors and 50 paramedical personnel working in an air-conditioned intensive care unit and operating theatres of the Government Rajaji Hospital, Madurai in India were studied by means of a questionnaire survey. In the present study, respiratory and ocular symptoms were observed more in those working in operating theatres and were believed to be due to excessive use of formaldehyde used for sterilization. Various suggestions were made to prevent sick building syndrome. Moreover, the physicians treating sick individuals should be aware of the symptoms caused by indoor air pollutants as sufferers invariably require a change of environment rather than drugs. (orig.).

  16. Investigation of the molecular motions in Cd(NH/sub 3/)/sub 6/Cl/sub 2/ by NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pislewski, N [Polska Akademia Nauk, Poznan. Inst. Fizyki Molekularnej; Ferris, L T.H. [University Coll., London (UK). Dept. of Chemistry

    1981-07-01

    NMR results are reported for intramolecular motion in Cd(NH/sub 3/)/sub 6/Cl/sub 2/. Below the 180 K phase transition, the motion of the NH/sub 3/ groups is well described by the Hilt-Hubbard theory with an activation energy of 9.63 kJ/mol. The inter-proton distance in NH/sub 3/ determined from relaxational measurements is 0.161 nm. Several K below and above the transition point, two phases with different spin-lattice relaxation times coexist.

  17. An investigation into the validity of cervical spine motion palpation using subjects with congenital block vertebrae as a 'gold standard'

    Directory of Open Access Journals (Sweden)

    Peterson Cynthia K

    2004-06-01

    Full Text Available Abstract Background Although the effectiveness of manipulative therapy for treating back and neck pain has been demonstrated, the validity of many of the procedures used to detect joint dysfunction has not been confirmed. Practitioners of manual medicine frequently employ motion palpation as a diagnostic tool, despite conflicting evidence regarding its utility and reliability. The introduction of various spinal models with artificially introduced 'fixations' as an attempt to introduce a 'gold standard' has met with frustration and frequent mechanical failure. Because direct comparison against a 'gold standard' allows the validity, specificity and sensitivity of a test to be calculated, the identification of a realistic 'gold standard' against which motion palpation can be evaluated is essential. The objective of this study was to introduce a new, realistic, 'gold standard', the congenital block vertebra (CBV to assess the validity of motion palpation in detecting a true fixation. Methods Twenty fourth year chiropractic students examined the cervical spines of three subjects with single level congenital block vertebrae, using two commonly employed motion palpation tests. The examiners, who were blinded to the presence of congenital block vertebrae, were asked to identify the most hypomobile segment(s. The congenital block segments included two subjects with fusion at the C2–3 level and one with fusion at C5-6. Exclusion criteria included subjects who were frankly symptomatic, had moderate or severe degenerative changes in their cervical spines, or displayed signs of cervical instability. Spinal levels were marked on the subject's skin overlying the facet joints from C1 to C7 bilaterally and the motion segments were then marked alphabetically with 'A' corresponding to C1-2. Kappa coefficients (K were calculated to determine the validity of motion palpation to detect the congenitally fused segments as the 'most hypomobile' segments. Sensitivity

  18. Physical work environment risk factors for long term sickness absence: prospective findings among a cohort of 5357 employees in Denmark

    DEFF Research Database (Denmark)

    Lund, Thomas; Labriola, Merete; Christensen, Karl Bang

    2006-01-01

    employees interviewed in 2000 about their physical work environment, and various covariates were followed for 18 months in a national sickness absence register. Outcome measurements Cox regression analysis was performed to assess risk estimates for physical risk factors in the work environment and onset......OBJECTIVES: To examine the effects of physical work environment on long term sickness absence and to investigate interaction between physical and psychosocial risk factors. DESIGN AND SETTING: Prospective cohort study of long term sickness absence among employees in Denmark. PARTICIPANTS: 5357...... of long term sickness absence, defined as receiving sickness absence compensation for eight consecutive weeks or more. RESULTS: 348 participants (6.9%) developed long term sickness absence during follow-up. Of these, 194 (55.7%) were women and 154 (44.3%) were men. For both female and male employees, risk...

  19. Tissue Respiration and Glycolysis in the Development of Acute Radiation Sickness

    National Research Council Canada - National Science Library

    Golubentsev, D

    1960-01-01

    The condition of tissue respiration and glycolysis in the development of acute radiation sickness has been insufficiently studied, and the factual data and opinions of various investigators are frequently contradictory...

  20. How primary health care physicians make sick listing decisions: The impact of medical factors and functioning

    Directory of Open Access Journals (Sweden)

    Svärdsudd Kurt

    2008-01-01

    Full Text Available Abstract Background The decision to issue sickness certification in Sweden for a patient should be based on the physician's assessment of the reduction of the patient's work capacity due to a disease or injury, not on psychosocial factors, in spite of the fact that they are known as risk factors for sickness absence. The aim of this study was to investigate the influence of medical factors and functioning on sick listing probability. Methods Four hundred and seventy-four patient-physician consultations, where sick listing could be an option, in general practice in Örebro county, central Sweden, were documented using physician and patient questionnaires. Information sought was the physicians' assessments of causes and consequences of the patients' complaints, potential to recover, diagnoses and prescriptions on sick leave, and the patients' view of their family and work situation and functioning as well as data on the patients' former and present health situation. The outcome measure was whether or not a sickness certificate was issued. Multivariate analyses were performed. Results Complaints entirely or mainly somatic as assessed by the physician decreased the risk of sick listing, and complaints resulting in severe limitation of occupational work capacity, as assessed by the patient as well as the physician, increased the risk of sick listing, as did appointments for locomotor complaints. The results for patients with infectious diseases or musculoskeletal diseases were partly similar to those for all diseases. Conclusion The strongest predictors for sickness certification were patient's and GP's assessment of reduced work capacity, with a striking concordance between physician and patient on this assessment. When patient's complaints were judged to be non-somatic the risk of sickness certification was enhanced.

  1. The Prognostic Value of the Work Ability Index for Sickness Absence among Office Workers.

    Science.gov (United States)

    Reeuwijk, Kerstin G; Robroek, Suzan J W; Niessen, Maurice A J; Kraaijenhagen, Roderik A; Vergouwe, Yvonne; Burdorf, Alex

    2015-01-01

    The work ability index (WAI) is a frequently used tool in occupational health to identify workers at risk for a reduced work performance and for work-related disability. However, information about the prognostic value of the WAI to identify workers at risk for sickness absence is scarce. To investigate the prognostic value of the WAI for sickness absence, and whether the discriminative ability differs across demographic subgroups. At baseline, the WAI (score 7-49) was assessed among 1,331 office workers from a Dutch financial service company. Sickness absence was registered during 12-months follow-up and categorised as 0 days, 0performed for separate WAI dimensions, and subgroup analyses for demographic groups. A lower WAI was associated with sickness absence (≥15 days vs. 0 days: per point lower WAI score OR=1.27; 95%CI 1.21-1.33). The WAI showed reasonable ability to discriminate between categories of sickness absence (ORC=0.65; 95%CI 0.63-0.68). Highest discrimination was found for comparing workers with ≥15 sick days with 0 sick days (AUC=0.77) or with 1-5 sick days (AUC=0.69). At the cut-off for poor work ability (WAI≤27) the sensitivity to identify workers at risk for ≥15 sick days was 7.5%, the specificity 99.6%, and the positive predictive value 82%. The performance was similar across demographic subgroups. The WAI could be used to identify workers at high risk for prolonged sickness absence. However, due to low sensitivity many workers will be missed. Hence, additional factors are required to better identify workers at highest risk.

  2. Leadership styles of nurse managers and registered sickness absence among their nursing staff.

    Science.gov (United States)

    Schreuder, Jolanda A H; Roelen, Corné A M; van Zweeden, Nely F; Jongsma, Dianne; van der Klink, Jac J L; Groothoff, Johan W

    2011-01-01

    Sickness absence leads to understaffing and interferes with nursing efficiency and quality. It has been reported in literature that managerial leadership is associated with self-reported sickness absence in the working population. This study investigated the relationship between managerial leadership and sickness absence in health care by associating nurse managers' leadership styles with registered sickness absence among their nursing staff. The cross-sectional study included 699 nurses working in six wards (staff range = 91-140 employees) of a Dutch somatic hospital employing a total of 1,153 persons. The nurse managers heading the wards were asked to complete the Leadership Effectiveness and Adaptability Description questionnaire for situational leadership. The Leadership Effectiveness and Adaptability Description scores were linked to employer-registered nursing staff sickness absence. High relationship-high task behavior (odds ratio [OR] = 0.76, 95% confidence interval [CI] = 0.65-0.85) and high relationship-low task behavior (OR = 0.37, 95% CI = 0.14 -0.98) were inversely related to the number of short (one to seven consecutive days) episodes of sickness absence among the staff. Low relationship-high task styles (OR = 2.44, 95% CI = 1.14-5.22) as well as low relationship-low task styles (OR = 2.44, 95% CI = 1.26-4.71) were positively associated with the number of short episodes of sickness absence. However, the leadership styles only explained 10% of the variance in short episodes of sickness absence. Leadership styles are associated with registered sickness absence. The nursing staff of relationship-oriented nurse managers has fewer short episodes of sickness absence than the staff of task-oriented managers. Training nurse managers in relational leadership styles may reduce understaffing and improve nursing efficiency and quality.

  3. Sickness presenteeism: The prevalence of coming to work while ill among paediatric resident physicians in Canada.

    Science.gov (United States)

    Mitchell, Kevin J; Vayalumkal, Joseph V

    2017-05-01

    Sickness presenteeism is defined as the act of attending one's job despite ill-health. Recently, physicians and other health care workers have become the focus of sickness presenteeism research, because presenteeism in this population can put patients at risk of infection. There are currently no data on this topic among physicians in Canada. The aim of this study was to investigate sickness presenteeism in paediatric resident physicians in Canada. We conducted an anonymous, online, cross-sectional survey study in which all paediatric residents in Canada were eligible. Outcomes of interest included prevalences of sickness presenteeism, sickness during the study period and voluntary self-appointed personal protective equipment use when engaging in sickness presenteeism. Response rate was 56.5% (N=323). During the previous 2 months, 61% (95% confidence interval [CI] 55.7 to 66.3) of respondents reported having experienced an illness and 59% (95% CI 53.7 to 64.5) of respondents had come to work sick. Of those who reported becoming ill during the study period, 97.0% (95% CI 94.6 to 99.4) reported coming to work while sick. There was no difference in prevalence when comparing across post-graduate year training levels. Extra personal protective equipment was used by 86% (95% CI 82.1 to 91.7) when engaging in sickness presenteeism. Sickness presenteeism is a common phenomenon among paediatric resident physicians. Our results should influence residents and supervising staff physicians to encourage appropriate self-care at home, rather than presenteeism.

  4. Labour market trajectories following sickness absence due to self-reported all cause morbidity-a longitudinal study

    DEFF Research Database (Denmark)

    Pedersen, Pernille; Lund, Thomas; Lindholdt, Louise

    2016-01-01

    BACKGROUND: To investigate differences in return to work (RTW) and employment trajectories in individuals on sick leave for either mental health reasons or other health related reasons. METHODS: This study was based on 2036 new sickness absence cases who completed a questionnaire on social charac...... compared to employees on sick leave due to other health reasons. The difference could be explained by their lower RTW expectations at baseline. This emphasises the need to develop suitable and specific interventions to facilitate RTW for this group of sickness absentees....

  5. Clinical characteristics of subacute radiation sickness

    International Nuclear Information System (INIS)

    Jiang Benrong; Ye Genyao; Huang Shimin

    1991-01-01

    The clinical characteristics, diagnosis and differential diagnosis of subacute radiation sickness are analysed and discussed in this paper on the basis of clinical data from cases in a 137 Cs source accident in Mudanjiang and of a review of the literature. We consider that the subacute radiation sickness is a whole body disease caused by comparatively large dose of continuous or intermittent external irradiation in several weeks or months. it must be differentiated from acute radiation sickness, chronic radiation sickness, idiopathic aplastic anemia and other hematological diseases, such as paroxysmal nocturnal hemoglobinuria, acute leukemia and myelodysplastic syndrome

  6. General practitioners' use of sickness certificates.

    Science.gov (United States)

    Roope, Richard; Parker, Gordon; Turner, Susan

    2009-12-01

    At present, sickness certification is largely undertaken by general practitioners (GPs). Guidance from the Department of Work and Pensions (DWP) is available to help with this task; however, there has been little formal evaluation of the DWP's guidance in relation to day-to-day general practice. To assess GPs' training, knowledge and application of the DWP's sickness certification guidelines. A structured questionnaire was sent to GPs within a (former) primary care trust (PCT). It probed demographics, training and knowledge of sickness certification guidelines. Case histories and structured questions were used to assess current practice. In this group of 113 GPs, there was a low awareness and use of the DWP's guidelines and Website relating to sickness certification. The majority of the GPs (63%) had received no training in sickness certification, and the mean length of time for those who had received training was 4.1 h. Most GPs also felt that patients and GPs have equal influence on the duration of sickness certification. This evidence of variable practice indicates that GPs should have more guidance and education in sickness certification. Closer sickness certification monitoring through existing GP computer systems may facilitate an improvement in practice that benefits patients and employers. The DWP, medical educators and PCTs may all have an additional role in further improving sickness certification practice.

  7. Office design's impact on sick leave rates.

    Science.gov (United States)

    Bodin Danielsson, Christina; Chungkham, Holendro Singh; Wulff, Cornelia; Westerlund, Hugo

    2014-01-01

    The effect of office type on sickness absence among office employees was studied prospectively in 1852 employees working in (1) cell-offices; (2) shared-room offices; (3) small, (4) medium-sized and (5) large open-plan offices; (6) flex-offices and (7) combi-offices. Sick leaves were self-reported two years later as number of (a) short and (b) long (medically certified) sick leave spells as well as (c) total number of sick leave days. Multivariate logistic regression analysis was used, with adjustment for background factors. A significant excess risk for sickness absence was found only in terms of short sick leave spells in the three open-plan offices. In the gender separate analysis, this remained for women, whereas men had a significantly increased risk in flex-offices. For long sick leave spells, a significantly higher risk was found among women in large open-plan offices and for total number of sick days among men in flex-offices. A prospective study of the office environment's effect on employees is motivated by the high rates of sick leaves in the workforce. The results indicate differences between office types, depending on the number of people sharing workspace and the opportunity to exert personal control as influenced by the features that define the office types.

  8. Mental disorder sick leave in Sweden: A population study.

    Science.gov (United States)

    Lidwall, Ulrik; Bill, Sofia; Palmer, Edward; Olsson Bohlin, Christina

    2018-01-01

    The inability to perform productive work due to mental disorders is a growing concern in advanced societies. To investigate medically certified mental disorder and all-cause sick leave in a working population using demographic, socioeconomic and occupational predictors. The study population was the entire Swedish work force aged 16-64 years in December 31st 2011. The outcome was sick leave exceeding 14 days in 2012 with adjustment for 13 confounders. The risk of sick leave with a mental disorder is higher among women compared to men, among persons aged 30-39 and among parents in families with underage children. Employees in welfare service occupations within health care, education and social services have an elevated risk of mental disorder sick leave and constitute a large proportion of the workforce. The results support the need for improving early detection and prevention of mental disorders in the workforce. Improvements in psychosocial work environments are essential, where the higher risk in female dominated welfare occupations particularly, have repercussions on the quality of the welfare services provided for vulnerable groups in society. Better work-life balance in families with younger children could also mitigate the effects of a high total workload in that particular phase of life.

  9. Dexmedetomidine reduces lipopolysaccharide induced neuroinflammation, sickness behavior, and anhedonia.

    Directory of Open Access Journals (Sweden)

    Ching-Hua Yeh

    Full Text Available Peripheral innate immune response may induce sickness behavior through activating microglia, excessive cytokines production, and neuroinflammation. Dexmedetomidine (Dex has anti-inflammatory effect. We investigated the effects of Dex on lipopolysaccharide (LPS-induced neuroinflammation and sickness behavior in mice.BALB/c mice were intraperitoneally (i.p. injected with Dex (50 ug/kg or vehicle. One hour later, the mice were injected (i.p. with Escherichia coli LPS (0.33 mg/kg or saline (n = 6 in each group. We analyzed the food and water intake, body weight loss, and sucrose preference of the mice for 24h. We also determined microglia activation and cytokines expression in the brains of the mice. In vitro, we determine cytokines expression in LPS-treated BV-2 microglial cells with or without Dex treatment.In the Dex-pretreated mice, LPS-induced sickness behavior (anorexia, weight loss, and social withdrawal were attenuated and microglial activation was lower than vehicle control. The mRNA expression of TNF-α, MCP-1, indoleamine 2, 3 dioxygenase (IDO, caspase-3, and iNOS were increased in the brain of LPS-challenged mice, which were reduced by Dex but not vehicle.Dexmedetomidine diminished LPS-induced neuroinflammation in the mouse brain and modulated the cytokine-associated changes in sickness behavior.

  10. Response margins investigation of piping dynamic analyses using the independent support motion method and PVRC [Pressure Vessel Research Committee] damping

    International Nuclear Information System (INIS)

    Bezler, P.; Wang, Y.K.; Reich, M.

    1988-03-01

    An evaluation of Independent Support Motion (ISM) response spectrum methods of analysis coupled with the Pressure Vessel Research Committee (PVRC) recommendation for damping, to compute the dynamic component of the seismic response of piping systems, was completed. Response estimates for five piping/structural systems were developed using fourteen variants of the ISM response spectrum method, the Uniform Support Motions response spectrum method and the ISM time history analysis method, all based on the PVRC recommendations for damping. The ISM/PVRC calculational procedures were found to exhibit orderly characteristics with levels of conservatism comparable to those obtained with the ISM/uniform damping procedures. Using the ISM/PVRC response spectrum method with absolute combination between group contributions provided consistently conservative results while using the ISM/PVRC response spectrum method with square root sum of squares combination between group contributions provided estimates of response which were deemed to be acceptable

  11. Experimental Investigation of the Self-Propelled Motion of a Sodium Oleate Tablet and Boat at an Oil-Water Interface.

    Science.gov (United States)

    Watahiki, Yasuhito; Nomoto, Tomonori; Chiari, Luca; Toyota, Taro; Fujinami, Masanori

    2018-05-15

    The self-propelled behaviors of macroscopic inanimate objects at surfaces and interfaces are ubiquitous phenomena of fundamental interest in interface science. However, given the existence of a large variety of systems with their own inherent chemical properties, the kinematics of the self-propelled motion and the dynamics of the forces driving these systems often remain largely unknown. Here, we experimentally investigate the spontaneous motion of a sodium oleate tablet at a water-nitrobenzene interface, under nonequilibrium and global isothermal conditions, through measurements of the interfacial tension with the noninvasive, quasi-elastic laser scattering method. The sodium oleate tablet was self-propelled due to an imbalance in the interfacial tension induced by the inhomogeneous adsorption of oleate/oleic acid molecules. The kinetics of the self-propelled motion of a boat-shaped plastic sheet bearing sodium oleate tablets at a sodium oleate aqueous solution-nitrobenzene interface was also studied. The interfacial tension difference between the front and rear of the boat was quantitatively identified as the force pushing the boat forward, although the Marangoni flow due to the uneven distribution of the interfacial tension behind the boat tended to decelerate the motion.

  12. The work ability index and single-item question: associations with sick leave, symptoms, and health--a prospective study of women on long-term sick leave.

    Science.gov (United States)

    Ahlstrom, Linda; Grimby-Ekman, Anna; Hagberg, Mats; Dellve, Lotta

    2010-09-01

    This study investigated the association between the work ability index (WAI) and the single-item question on work ability among women working in human service organizations (HSO) currently on long-term sick leave. It also examined the association between the WAI and the single-item question in relation to sick leave, symptoms, and health. Predictive values of the WAI, the changed WAI, the single-item question and the changed single-item question were investigated for degree of sick leave, symptoms, and health. This cohort study comprised 324 HSO female workers on long-term (>60 days) sick leave, with follow-ups at 6 and 12 months. Participants responded to questionnaires. Data on work ability, sick leave, health, and symptoms were analyzed with regard to associations and predictability. Spearman correlation and mixed-model analysis were performed for repeated measurements over time. The study showed a very strong association between the WAI and the single-item question among all participants. Both the WAI and the single-item question showed similar patterns of associations with sick leave, health, and symptoms. The predictive value for the degree of sick leave and health-related quality of life (HRQoL) was strong for both the WAI and the single-item question, and slightly less strong for vitality, neck pain, both self-rated general and mental health, and behavioral and current stress. This study suggests that the single-item question on work ability could be used as a simple indicator for assessing the status and progress of work ability among women on long-term sick leave.

  13. sick: The Spectroscopic Inference Crank

    Science.gov (United States)

    Casey, Andrew R.

    2016-03-01

    There exists an inordinate amount of spectral data in both public and private astronomical archives that remain severely under-utilized. The lack of reliable open-source tools for analyzing large volumes of spectra contributes to this situation, which is poised to worsen as large surveys successively release orders of magnitude more spectra. In this article I introduce sick, the spectroscopic inference crank, a flexible and fast Bayesian tool for inferring astrophysical parameters from spectra. sick is agnostic to the wavelength coverage, resolving power, or general data format, allowing any user to easily construct a generative model for their data, regardless of its source. sick can be used to provide a nearest-neighbor estimate of model parameters, a numerically optimized point estimate, or full Markov Chain Monte Carlo sampling of the posterior probability distributions. This generality empowers any astronomer to capitalize on the plethora of published synthetic and observed spectra, and make precise inferences for a host of astrophysical (and nuisance) quantities. Model intensities can be reliably approximated from existing grids of synthetic or observed spectra using linear multi-dimensional interpolation, or a Cannon-based model. Additional phenomena that transform the data (e.g., redshift, rotational broadening, continuum, spectral resolution) are incorporated as free parameters and can be marginalized away. Outlier pixels (e.g., cosmic rays or poorly modeled regimes) can be treated with a Gaussian mixture model, and a noise model is included to account for systematically underestimated variance. Combining these phenomena into a scalar-justified, quantitative model permits precise inferences with credible uncertainties on noisy data. I describe the common model features, the implementation details, and the default behavior, which is balanced to be suitable for most astronomical applications. Using a forward model on low-resolution, high signal

  14. SICK: THE SPECTROSCOPIC INFERENCE CRANK

    Energy Technology Data Exchange (ETDEWEB)

    Casey, Andrew R., E-mail: arc@ast.cam.ac.uk [Institute of Astronomy, University of Cambridge, Madingley Road, Cambdridge, CB3 0HA (United Kingdom)

    2016-03-15

    There exists an inordinate amount of spectral data in both public and private astronomical archives that remain severely under-utilized. The lack of reliable open-source tools for analyzing large volumes of spectra contributes to this situation, which is poised to worsen as large surveys successively release orders of magnitude more spectra. In this article I introduce sick, the spectroscopic inference crank, a flexible and fast Bayesian tool for inferring astrophysical parameters from spectra. sick is agnostic to the wavelength coverage, resolving power, or general data format, allowing any user to easily construct a generative model for their data, regardless of its source. sick can be used to provide a nearest-neighbor estimate of model parameters, a numerically optimized point estimate, or full Markov Chain Monte Carlo sampling of the posterior probability distributions. This generality empowers any astronomer to capitalize on the plethora of published synthetic and observed spectra, and make precise inferences for a host of astrophysical (and nuisance) quantities. Model intensities can be reliably approximated from existing grids of synthetic or observed spectra using linear multi-dimensional interpolation, or a Cannon-based model. Additional phenomena that transform the data (e.g., redshift, rotational broadening, continuum, spectral resolution) are incorporated as free parameters and can be marginalized away. Outlier pixels (e.g., cosmic rays or poorly modeled regimes) can be treated with a Gaussian mixture model, and a noise model is included to account for systematically underestimated variance. Combining these phenomena into a scalar-justified, quantitative model permits precise inferences with credible uncertainties on noisy data. I describe the common model features, the implementation details, and the default behavior, which is balanced to be suitable for most astronomical applications. Using a forward model on low-resolution, high signal

  15. SICK: THE SPECTROSCOPIC INFERENCE CRANK

    International Nuclear Information System (INIS)

    Casey, Andrew R.

    2016-01-01

    There exists an inordinate amount of spectral data in both public and private astronomical archives that remain severely under-utilized. The lack of reliable open-source tools for analyzing large volumes of spectra contributes to this situation, which is poised to worsen as large surveys successively release orders of magnitude more spectra. In this article I introduce sick, the spectroscopic inference crank, a flexible and fast Bayesian tool for inferring astrophysical parameters from spectra. sick is agnostic to the wavelength coverage, resolving power, or general data format, allowing any user to easily construct a generative model for their data, regardless of its source. sick can be used to provide a nearest-neighbor estimate of model parameters, a numerically optimized point estimate, or full Markov Chain Monte Carlo sampling of the posterior probability distributions. This generality empowers any astronomer to capitalize on the plethora of published synthetic and observed spectra, and make precise inferences for a host of astrophysical (and nuisance) quantities. Model intensities can be reliably approximated from existing grids of synthetic or observed spectra using linear multi-dimensional interpolation, or a Cannon-based model. Additional phenomena that transform the data (e.g., redshift, rotational broadening, continuum, spectral resolution) are incorporated as free parameters and can be marginalized away. Outlier pixels (e.g., cosmic rays or poorly modeled regimes) can be treated with a Gaussian mixture model, and a noise model is included to account for systematically underestimated variance. Combining these phenomena into a scalar-justified, quantitative model permits precise inferences with credible uncertainties on noisy data. I describe the common model features, the implementation details, and the default behavior, which is balanced to be suitable for most astronomical applications. Using a forward model on low-resolution, high signal

  16. Investigating the significance of zero-point motion in small molecular clusters of sulphuric acid and water

    International Nuclear Information System (INIS)

    Stinson, Jake L.; Ford, Ian J.; Kathmann, Shawn M.

    2014-01-01

    The nucleation of particles from trace gases in the atmosphere is an important source of cloud condensation nuclei, and these are vital for the formation of clouds in view of the high supersaturations required for homogeneous water droplet nucleation. The methods of quantum chemistry have increasingly been employed to model nucleation due to their high accuracy and efficiency in calculating configurational energies; and nucleation rates can be obtained from the associated free energies of particle formation. However, even in such advanced approaches, it is typically assumed that the nuclei have a classical nature, which is questionable for some systems. The importance of zero-point motion (also known as quantum nuclear dynamics) in modelling small clusters of sulphuric acid and water is tested here using the path integral molecular dynamics method at the density functional level of theory. The general effect of zero-point motion is to distort the mean structure slightly, and to promote the extent of proton transfer with respect to classical behaviour. In a particular configuration of one sulphuric acid molecule with three waters, the range of positions explored by a proton between a sulphuric acid and a water molecule at 300 K (a broad range in contrast to the confinement suggested by geometry optimisation at 0 K) is clearly affected by the inclusion of zero point motion, and similar effects are observed for other configurations

  17. The influence of household work and of having children on sickness absence among publicly employed women in Sweden.

    Science.gov (United States)

    Voss, Margaretha; Josephson, Malin; Stark, Stefan; Vaez, Marjan; Alexanderson, Kristina; Alfredsson, Lars; Vingård, Eva

    2008-08-01

    To investigate whether family obligations influence the risk of sickness absence among female municipal employees in Sweden. A 1-year prospective cohort study of 1464 female municipal employees work, financial situation, working hours and work-family conflicts for repeated sick-leave spells (>or=4 spells) and long-term sickness absence (>or=28 days) were calculated by applying Poisson regression models. Women reporting financial strain or work-family conflicts were at elevated risk for long-term sickness absence. Having children was not a risk factor for repeated sick-leave spells or long-term sickness absence among married/cohabiting women. Single women with children had a two-fold greater risk of repeated sick-leave spells than single women without children. The findings suggest that the combination of gainful employment and children does not influence the risk of repeated sick-leave spells or long-term sickness absence among married/cohabiting publicly employed women. However, this was not true for single women with children, which indicates that their circumstances are particularly strained.

  18. Indoor air pollution and sick building syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, J P

    1997-12-31

    The topics discussed in this paper are accept that SBS (Sick building syndrome) is a reality ; understand the dimensions of the problem ; differentiate between sick building syndrome and building related illness ; introduce standards ; understanding the economics ; act pro-actively not re-actively.

  19. GENETIC PREDICTORS OF IDIOPATHIC SICK SINUS SYNDROME

    Directory of Open Access Journals (Sweden)

    A. A. Chernova

    2012-01-01

    Full Text Available Published data demonstrating genetic determination of sick sinus syndrome is presented. The definition of this pathology is presented; the main symptoms are described, as well as genes that influence the development of idiopathic sick sinus syndrome, their polymorphisms and role in disorders of the cardiovascular system.

  20. Indoor air pollution and sick building syndrome

    International Nuclear Information System (INIS)

    Robertson, J.P.

    1996-01-01

    The topics discussed in this paper are accept that SBS (Sick building syndrome) is a reality ; understand the dimensions of the problem ; differentiate between sick building syndrome and building related illness ; introduce standards ; understanding the economics ; act pro-actively not re-actively

  1. Characteristics of sick-listing cases that physicians consider problematic--analyses of written case reports.

    Science.gov (United States)

    Engblom, Monika; Alexanderson, Kristina; Rudebeck, Carl Edvard

    2009-01-01

    The aim was to discern common characteristics in the sick-listing cases that physicians in general practice and occupational health services find problematic. Descriptive categorization within a narrative theoretical framework. Sickness-insurance course for physicians in general practice and occupational health services. A total of 195 case reports written by 195 physicians. Main outcome measures. Categories of features regarding medical, work, and social situation as well as medical interventions. Beside age and sex, the following information was often provided: family situation, stressful life events, occupation, problem at work, considerations concerning diagnoses, medical investigations, treatments, and vocational rehabilitation measures. Two-thirds of the patients had been sickness absent for more than a year. The most common type of case reports concerned women, employed in non-qualified nursing occupations, and sick listed due to mental disorders. The most common measures taken by the physicians were referrals to psychotherapy and/or physiotherapy, and prescribing antidepressants (SSRI). Facts about alcohol habits were rarely provided in the cases. Some of the circumstances, such as prolonged sick-listing, are likely to be more or less inevitable in problematic sick-listing cases. Other circumstances, such as stress-full life events, more closely reflect what the reporting physicians find problematic. The categories identified can be regarded as markers of problematic sick-listing cases in general practice and occupational health service.

  2. Association Between Cortisol to DHEA-s Ratio and Sickness Absence in Japanese Male Workers.

    Science.gov (United States)

    Hirokawa, Kumi; Fujii, Yasuhito; Taniguchi, Toshiyo; Takaki, Jiro; Tsutsumi, Akizumi

    2017-11-21

    This study aimed to investigate the association between serum levels of cortisol and dehydroepiandrosterone sulfate (DHEA-s) and sickness absence over 2 years in Japanese male workers. A baseline survey including questions about health behavior, along with blood sampling for cortisol and DHEA-s, was conducted in 2009. In total, 429 men (mean ± SD age, 52.9 ± 8.6 years) from whom blood samples were collected at baseline were followed until December 31, 2011. The hazard ratios (HR) and 95% confidence intervals (CI) for sickness absence were calculated using a Cox proportional hazard model, adjusted for potential confounders. Among 35 workers who took sickness absences, 31 had physical illness. A high cortisol to DHEA-s ratio increased the risk of sickness absence (crude HR = 2.68, 95% CI 1.12-6.41; adjusted HR = 3.33, 95% CI 1.35-8.20). The cortisol to DHEA-s ratio was linearly associated with an increased risk of sickness absence (p for trend sickness absences. This trend did not change when limited to absences resulting from physical illness. Hormonal conditions related to the hypothalamus-pituitary-adrenocortical axis and adrenal function should be considered when predicting sickness absence. The cortisol to DHEA-s ratio may be more informative than single effects of cortisol and DHEA-s levels.

  3. Gender and age differences in the recurrence of sickness absence due to common mental disorders : a longitudinal study

    NARCIS (Netherlands)

    Koopmans, P.C.; Roelen, C.A.M.; Bultmann, U.; Hoedeman, R.; van der Klink, J.J.L.; Groothoff, J.W.

    2010-01-01

    Background: Common mental disorders (CMDs) are an important cause of sickness absence and long-term work disability. Although CMDs are known to have high recurrence rates, little is known about the recurrence of sickness absence due to CMDs. The aim of this study was to investigate the recurrence of

  4. [Risk factors for absenteeism due to sick leave in the petroleum industry].

    Science.gov (United States)

    Oenning, Nágila Soares Xavier; Carvalho, Fernando Martins; Lima, Veronica Maria Cadena

    2014-02-01

    To identify risk factors for absenteeism among workers with sick leave in an oil company. A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. To identify risk factors for absenteeism among workers with sick leave in an oil company. A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to

  5. Self-reported noise exposure as a risk factor for long-term sickness absence

    DEFF Research Database (Denmark)

    Clausen, Thomas; Christensen, Karl Bang; Lund, Thomas

    2009-01-01

    men and women when adjusting for demographic factors and health behavior. After further adjustment for physical workload at work the association between noise exposure and sickness absence disappeared for women, but not for men. Men that reported to be exposed to loud noise between one......Self-reported noise exposure is on the rise in Denmark. Little is known, however, about the social consequences, including sickness absence, of noise exposure. The aim of this paper was to investigate the association between self-reported noise exposure and long-term sickness absence....... The association was investigated using the Cox proportional hazards model to analyze outcomes in Danish register data on the basis of Danish survey data (5357 employees aged 18-69 in 2000). The analyses showed that self-reported noise exposure was significantly associated with long-term sickness absence for both...

  6. Archives, libraries and museums: containers often sick, sometimes seriously sick

    Directory of Open Access Journals (Sweden)

    Roberto Nicolucci

    2007-07-01

    Full Text Available As far as the feeling of quietness and peace that they often convey, archives, museums and libraries also hide dangers that you may not imagine, either for visitors or especially for the members of the staff. Indeed the poor microclimatic conditions – often the consequences of materials and construction or building technologies that appear definitely obsolete – often arouse suspicion and worry among the staff. Wrong Thermo hygrometric parameters, the presence of volatile organic elements, mineral fibers, biocides, radon gas, aerial dispersive molecules, are among others some of the chemical physical polluters of major influence that may contribute to giving life to the so-called Sick Building Syndrome. But such spaces also bear biological polluters that can provoke pathologies of various types and importance, among which the feared Illness of Legionnaire. The presence of electromagnetic fields, but above all wrong lighting and wrong ergonomic working positions represent some risk factors for members of staff and visitors.

  7. Risk factors for absenteeism due to sick leave in the petroleum industry

    Science.gov (United States)

    Oenning, Nágila Soares Xavier; Carvalho, Fernando Martins; Lima, Veronica Maria Cadena

    2014-01-01

    OBJECTIVE To identify risk factors for absenteeism among workers with sick leave in an oil company. METHODS A case-control study (120 cases and 656 controls) nested in a retrospective cohort study following up all employees of an oil company in the North-Northeast of Brazil from 2007 to 2009. The response variable used to represent absenteeism with sick leave was the average incidence of sick leave, defined as the ratio between total sick days and potential working days in the period. Logistic regression techniques were used to investigate the association between average incidence of sick leave > 5.0% over the period and the variables sex, position, age, time at work, shift work, smoking, arterial hypertension, body mass index, physical activity, coronary risk, sleep, glycemia, non-managed diabetes, cardiovascular, digestive, musculoskeletal, neurological and neoplastic diseases, straining body positioning during work, satisfaction at work, relationship with management, and concentrated attention at work. RESULTS Average incidence of sick leave higher than 5.0% in the cohort period was 15.5%. The logistic model revealed that workers with average incidence of sick leave higher than 5.0% were 2.6 times more likely to be female; 2.0 time more likely to be smokers; 1.8 time more likely to be former smokers; 2.2 times more likely to report abnormal sleep and 10.5 times more likely to report dissatisfaction with their than workers with average incidence of sick leave ≤ 5.0% in the period. CONCLUSIONS In this population, female gender, being a smoker or a former smoker, reporting dissatisfaction with the job and reporting abnormal sleep are good predictors of occupational absenteeism with sick leave. PMID:24789643

  8. Design and experimental investigation of a magnetically coupled vibration energy harvester using two inverted piezoelectric cantilever beams for rotational motion

    International Nuclear Information System (INIS)

    Zou, Hong-Xiang; Zhang, Wen-ming; Li, Wen-Bo; Wei, Ke-Xiang; Gao, Qiu-Hua; Peng, Zhi-Ke; Meng, Guang

    2017-01-01

    Highlights: • A magnetically coupled two-degree-of-freedom harvester for rotation is proposed. • The electromechanical coupling model is developed and validated experimentally. • The harvester can generate high voltage at low rotating speeds. • The harvester can harvest vibration energy in multiple frequency bands. - Abstract: Energy can be harvested from rotational motion for powering wireless autonomous electronic devices. The paper presents a magnetically coupled two-degree-of-freedom vibration energy harvester for rotary motion applications. The design consists of two inverted piezoelectric cantilever beams whose free ends point to the rotating shaft. The centrifugal force of the inverted cantilever beam is beneficial to producing large amplitude in a low speed range. The electromechanical coupling dynamical model is developed by the energy method from Hamilton’s principle and validated experimentally. The experimental results indicate that the presented harvester is suitable for low speed rotation and can harvest vibration energy in multiple frequency bands. The first and second resonant behaviors of voltage can be obtained at 420 r/min and 550 r/min, and the average output powers are 564 μW and 535.3 μW, respectively.

  9. A ‘Balanced’ Life: Work-Life Balance and Sickness Absence in Four Nordic Countries

    OpenAIRE

    D Antai; A Oke; P Braithwaite; DS Anthony

    2015-01-01

    Background: Little attention has been given to the relationship between work-life balance and sickness absence. Objective: To investigate the association between poor work-life balance and sickness absence in 4 Nordic welfare states. Methods: Multivariable logistic regression analysis was performed on pooled cross-sectional data of workers aged 15–65 years from Denmark, Finland, Sweden, and Norway (n=4186) obtained from the 2010 European Working Conditions Survey (EWCS). Poor work-lif...

  10. Acute high-altitude sickness

    Directory of Open Access Journals (Sweden)

    Andrew M. Luks

    2017-02-01

    Full Text Available At any point 1–5 days following ascent to altitudes ≥2500 m, individuals are at risk of developing one of three forms of acute altitude illness: acute mountain sickness, a syndrome of nonspecific symptoms including headache, lassitude, dizziness and nausea; high-altitude cerebral oedema, a potentially fatal illness characterised by ataxia, decreased consciousness and characteristic changes on magnetic resonance imaging; and high-altitude pulmonary oedema, a noncardiogenic form of pulmonary oedema resulting from excessive hypoxic pulmonary vasoconstriction which can be fatal if not recognised and treated promptly. This review provides detailed information about each of these important clinical entities. After reviewing the clinical features, epidemiology and current understanding of the pathophysiology of each disorder, we describe the current pharmacological and nonpharmacological approaches to the prevention and treatment of these diseases.

  11. System for analysing sickness absenteeism in Poland.

    Science.gov (United States)

    Indulski, J A; Szubert, Z

    1997-01-01

    The National System of Sickness Absenteeism Statistics has been functioning in Poland since 1977, as the part of the national health statistics. The system is based on a 15-percent random sample of copies of certificates of temporary incapacity for work issued by all health care units and authorised private medical practitioners. A certificate of temporary incapacity for work is received by every insured employee who is compelled to stop working due to sickness, accident, or due to the necessity to care for a sick member of his/her family. The certificate is required on the first day of sickness. Analyses of disease- and accident-related sickness absenteeism carried out each year in Poland within the statistical system lead to the main conclusions: 1. Diseases of the musculoskeletal and peripheral nervous systems accounting, when combined, for 1/3 of the total sickness absenteeism, are a major health problem of the working population in Poland. During the past five years, incapacity for work caused by these diseases in males increased 2.5 times. 2. Circulatory diseases, and arterial hypertension and ischaemic heart disease in particular (41% and 27% of sickness days, respectively), create an essential health problem among males at productive age, especially, in the 40 and older age group. Absenteeism due to these diseases has increased in males more than two times.

  12. Investigation of the motion of a viscous fluid in the vitreous cavity induced by eye rotations and implications for drug delivery

    International Nuclear Information System (INIS)

    Bonfiglio, Andrea; Repetto, Rodolfo; Stocchino, Alessandro; Siggers, Jennifer H

    2013-01-01

    Intravitreal drug delivery is a commonly used treatment for several retinal diseases. The objective of this research is to characterize and quantify the role of the vitreous humor motion, induced by saccadic movements, on drug transport processes in the vitreous chamber. A Perspex model of the human vitreous chamber was created, and filled with a purely viscous fluid, representing eyes with a liquefied vitreous humor or those containing viscous tamponade fluids. Periodic movements were applied to the model and the resulting three-dimensional (3D) flow fields were measured. Drug delivery within the vitreous chamber was investigated by calculating particle trajectories using integration over time of the experimental velocity fields. The motion of the vitreous humor generated by saccadic eye movements is intrinsically 3D. Advective mass transport largely overcomes molecular diffusive transport and is significantly anisotropic, leading to a much faster drug dispersion than in the case of stationary vitreous humor. Disregarding the effects of vitreous humor motion due to eye movements when predicting the efficiency of drug delivery treatments leads to significant underestimation of the drug transport coefficients, and this, in turn, will lead to significantly erroneous predictions of the concentration levels on the retina. (paper)

  13. Explaining the gender gap in sickness absence.

    Science.gov (United States)

    Østby, K A; Mykletun, A; Nilsen, W

    2018-04-17

    In many western countries, women have a much higher rate of sickness absence than men. To what degree the gender differences in sickness absence are caused by gender differences in health is largely unknown. To assess to what degree the gender gap in sickness absence can be explained by health factors and work- and family-related stressors. Norwegian parents participating in the Tracking Opportunities and Problems (TOPP) study were asked about sickness absence and a range of factors possibly contributing to gender differences in sickness absence, including somatic and mental health, sleep problems, job control/demands, work-home conflicts, parent-child conflicts and stressful life events. Using a cross-sectional design, we did linear regression analyses, to assess the relative contribution from health and stressors. There were 557 study participants. Adjusting for health factors reduced the gender difference in sickness absence by 24%, while adjusting for stressors in the family and at work reduced the difference by 22%. A simultaneous adjustment for health factors and stressors reduced the difference in sickness absence by about 28%. Despite adjusting for a large number of factors, including both previously well-studied factors (e.g. health, job control/demands) and lesser-studied factors (parent-child conflict and sexual assault), this study found that most of the gender gap in sickness absence remains unexplained. Gender differences in health and stressors account for only part of the differences in sickness absence. Other factors must, therefore, exist outside the domains of health, work and family stressors.

  14. Workplace levels of psychosocial factors as prospective predictors of registered sickness absence

    DEFF Research Database (Denmark)

    Christensen, Karl Bang; Nielsen, Martin L; Rugulies, Reiner

    2005-01-01

    OBJECTIVE: We sought to investigate whether workplace levels of psychosocial work environment factors predict individual sickness absence. METHODS: Data were collected in a prospective study in 52 Danish workplaces in three organizations: municipal care, technical services, and a pharmaceutical...... company. Psychosocial factors were aggregated as workplace means. We used multilevel Poisson regression models with psychosocial factors as predictors and individual level sickness absence from absence registries as outcome. RESULTS: High workplace levels of decision authority predicted low sickness...... absence in the technical services (rate ratio = 0.66, 95% confidence interval = 0.51-0.86) and high workplace levels of skill discretion predicted low sickness absence in the pharmaceutical company (rate ratio = 0.74, 95% confidence interval = 0.62-0.88) after control for relevant confounders. Workplaces...

  15. Self-reported health and sickness benefits among parents of children with a disability.

    Science.gov (United States)

    Wendelborg, Christian; Tøssebro, Jan

    2016-07-02

    This article investigates the possible consequences in self-reported health and receipt of sickness benefits when parenting a child with a disability This study uses data from the population health study, The Nord-Trøndelag Health Study (HUNT 2), and the historical event database, FD-Trygd, which contains Social Security and national insurance data for the Norwegian population. In the analysis, we compare 1587 parents of a child with a disability to other parents. Results indicate that parenting a disabled child impacts on self-reported health, particularly among mothers; however, being a parent to a disabled child has a much stronger effect in explaining the variance in received sickness benefits, and also length of time and frequency of having received sickness benefits. Parents with disabled children report just slightly lower self-reported health but are on sickness benefits more often than other parents which may be attributed to their extended care responsibilities.

  16. Job strain and informal caregiving as predictors of long-term sickness absence

    DEFF Research Database (Denmark)

    Mortensen, Jesper; Dich, Nadya; Lange, Theis

    2017-01-01

    OBJECTIVES: The aim of this study was to investigate the individual, joint and interactive effects of job strain and informal caregiving on long-term sickness absence with special attention to gender differences. METHODS: The study comprised a prospective cohort study of 6798 working adults from...... France, 14 727 from Finland, and 5275 from the UK. A total of 26 800 participants, age 52 (interquartile range 47-56) years participated in the study. Job strain was assessed using the demand-control model. Informal caregiving was defined as care for a sick, disabled, or elderly person. Long......-term sickness absence spells defined as absence >14 consecutive days were registered during two years follow-up. We used recurrent-events Cox regression in random-effects meta-analyses. RESULTS: A total of 12% men and 21% women had ≥1 long-term sickness absence spell. Among women, both high job strain [hazard...

  17. Differences in sickness absence in Sweden and Denmark: the cross national HAKNAK study

    DEFF Research Database (Denmark)

    Lund, Thomas; Christensen, Karl Bang; Vaez, Marjan

    2009-01-01

    AIM: To investigate potential differences in sickness absence among public sector employees in Sweden and Denmark, and to what extent a difference was associated with age, gender, physical and psychosocial work environment exposures, lifestyle factors, self-rated health or work ability. METHODS...... of dependent and independent variables in the two sub-cohorts. Stratified logistic regression analysis was performed to identify causes for absence within the two sub-cohorts, and logistic regression analysis was performed to study differences in sickness absence levels between the two sub-cohorts. RESULTS......: More subjects from the Swedish study population reported more than 7 days of sickness absence. Factors associated with sickness absence were largely similar in the two countries. The difference in absence level between Sweden and Denmark was not associated with differences in age, gender, skill level...

  18. Does computer use pose a hazard for future long-term sickness absence?

    DEFF Research Database (Denmark)

    Andersen, JH; Mikkelsen, Sigurd

    2010-01-01

    The aim of the study was to investigate if weekly duration of computer use predicted sickness absence for more than two weeks at a later time.A cohort of 2146 frequent computer users filled in a questionnaire at baseline and was followed for one year with continuously recording of the duration of...... and upper limb, and it seems that computer use neither predicts future long-term sickness absence of all causes.......The aim of the study was to investigate if weekly duration of computer use predicted sickness absence for more than two weeks at a later time.A cohort of 2146 frequent computer users filled in a questionnaire at baseline and was followed for one year with continuously recording of the duration...... of computer use and furthermore followed for 300 weeks in a central register of sickness absence for more than 2 weeks.147 participants of the 2,146 (6.9%) became first time sick listed in the follow-up period. Overall, mean weekly computer use did not turn out to be a risk factor for later sickness absence...

  19. When healthcare workers get sick: exploring sickness absenteeism in British Columbia, Canada.

    Science.gov (United States)

    Gorman, Erin; Yu, Shicheng; Alamgir, Hasanat

    2010-01-01

    To determine the demographic and work characteristics of healthcare workers who were more likely to take sickness absences from work in British Columbia, Canada. Payroll data were analyzed for three health regions. Sickness absence rates were determined per person-year and then compared across demographic and work characteristics using multivariate Poisson regression models. The direct costs to the employer due to sickness absences were also estimated. Female, older, full-time workers, long-term care workers and those with a lower hourly wage were more likely to take sickness absences and had similar trends with respect to the costs due to sickness absence. For occupations, licensed practical nurses, care aides and facility support workers had higher rates of sickness absence. Registered nurses, and those workers paid high hourly wages were associated with highest sickness related costs. It is important to understand the demographic and work characteristics of those workers who are more likely to take sickness absences in order to make sure that they are not experiencing additional hazards at work or facing detrimental workplace conditions. Policy makers need to establish healthy, safe and in turn more productive workplaces. Further research is needed on how interventions can reduce sickness absence.

  20. An investigation of head movement with a view to minimising motion artefact during SPECT and PET imaging of the brain

    International Nuclear Information System (INIS)

    Patterson, H.; Clarke, G.H.; Guy, R.; McKay, W.J.

    1998-01-01

    Full text: Motion artefact has long been recognised as a major cause of image degradation. Single Photon Emission Computerised Tomography (SPECT) and Positron Emission Tomography (PET) of the brain are playing an important role in the diagnosis and management of several neurological disorders. If these imaging modalities are to contribute fully to medical imaging it is essential that the improved spatial resolution of these systems is not compromised by patient movement. Thirty volunteer subjects have been examined using a simple video technique and the video images were used to classify and measure head movements which may occur during brain imaging. All subjects demonstrated angular movement within the transverse plane or rotation of the head. Angular movement within the sagittal plane or flexion/extension of the neck occurred in 69% of subjects and 72% of subjects exhibited translational movement of the sagittal plane. There was no movement of the coronal plane; nor was there any translational movement of the sagittal plane. These results suggest that when positioning the patient's head for brain imaging a system of head restraint which minimises rotation of the head should be used if image quality is to be maintained

  1. Airsickness and aircraft motion during short-haul flights.

    Science.gov (United States)

    Turner, M; Griffin, M J; Holland, I

    2000-12-01

    There is little quantitative information that can be used to predict the incidence of airsickness from the motions experienced in military or civil aviation. This study examines the relationship between low-frequency aircraft motion and passenger sickness in short-haul turboprop flights within the United Kingdom. A questionnaire survey of 923 fare-paying passengers was conducted on 38 commercial airline flights. Concurrent measurements of aircraft motion were made on all journeys, yielding approximately 30 h of aircraft motion data. Overall, 0.5% of passengers reported vomiting, 8.4% reported nausea (range 0% to 34.8%) and 16.2% reported illness (range 0% to 47.8%) during flight. Positive correlations were found between the percentage of passengers who experienced nausea or felt ill and the magnitude of low-frequency lateral and vertical motion, although neither motion uniquely predicted airsickness. The incidence of motion sickness also varied with passenger age, gender, food consumption and activity during air travel. No differences in sickness were found between passengers located in different seating sections of the aircraft, or as a function of moderate levels of alcohol consumption. The passenger responses suggest that a useful prediction of airsickness can be obtained from magnitudes of low frequency aircraft motion. However, some variations in airsickness may also be explained by individual differences between passengers and their psychological perception of flying.

  2. Associations between sickness absence and harassment, threats, violence, or discrimination: a cross-sectional study of the Swedish Police.

    Science.gov (United States)

    Svedberg, Pia; Alexanderson, Kristina

    2012-01-01

    To study if sick leave among employees in the Swedish Police was associated with experiences of discrimination, harassment, or (threats of) violence. All employees in the Swedish Police in 2005. Analyses of data from a questionnaire to all employees; 74% (n=16,725) responded. Odds ratios (OR) with 95% confidence intervals (CI) between sick leave and the studied factors were assessed. The rate of sickness absence was higher for women (12%) than for men (8%) (pmen had experienced discrimination, while more men reported harassment from the public and experiences of threats or violence. ORs were significant between sick-leave and discrimination, sexual harassment, and violence, and higher for the men. Associations between harassment from the public, threats of violence or violence, and sickness absence were statistically significant for men only. The study identifies the importance of investigating discrimination, harassment, and violence in relation to health outcomes for both male and female Police employees.

  3. Sick of inequality: gender and support for paid sick days.

    Science.gov (United States)

    Lindemann, Danielle J; Houser, Linda; White, Karen

    2015-01-01

    The availability of paid sick days (PSD) is on the forefront of policy issues relating to women's health and well-being. Previous research regarding PSD and other forms of family-work balance legislation has linked access to paid time off from work for addressing one's own or another's health concerns to a range of health benefits for working women and their families. In general, public support for such policies is high, but little work has tested the extent to which support extends to PSD. Researchers have yet to engage in a rigorous statistical analysis of public opinion on PSD, including whether opinion varies by gender. Using data from a 2013 poll of adults in New Jersey (n = 925), we bridged this research gap by conducting the first multivariate analysis of public attitudes toward PSD. As expected, we found markedly high levels of support for PSD across all respondents, with a preponderance of most sociodemographic categories supporting proposed PSD legislation in New Jersey. We also found that gender was a strong predictor of support for PSD, with women significantly (odds ratio, 1.916; p ≤ .01) more likely than men to be in favor of such legislation. We discuss the implications of our findings for future work on PSD as well as for research concerning women, wellness, and work-life legislation more broadly. Published by Elsevier Inc.

  4. Extension of the NCAT phantom for the investigation of intra-fraction respiratory motion in IMRT using 4D Monte Carlo

    International Nuclear Information System (INIS)

    McGurk, Ross; Seco, Joao; Wolfgang, John; Paganetti, Harald; Riboldi, Marco; Segars, Paul

    2010-01-01

    The purpose of this work was to create a computational platform for studying motion in intensity modulated radiotherapy (IMRT). Specifically, the non-uniform rational B-spline (NURB) cardiac and torso (NCAT) phantom was modified for use in a four-dimensional Monte Carlo (4D-MC) simulation system to investigate the effect of respiratory-induced intra-fraction organ motion on IMRT dose distributions as a function of diaphragm motion, lesion size and lung density. Treatment plans for four clinical scenarios were designed: diaphragm peak-to-peak amplitude of 1 cm and 3 cm, and two lesion sizes-2 cm and 4 cm diameter placed in the lower lobe of the right lung. Lung density was changed for each phase using a conservation of mass calculation. Further, a new heterogeneous lung model was implemented and tested. Each lesion had an internal target volume (ITV) subsequently expanded by 15 mm isotropically to give the planning target volume (PTV). The PTV was prescribed to receive 72 Gy in 40 fractions. The MLC leaf sequence defined by the planning system for each patient was exported and used as input into the MC system. MC simulations using the dose planning method (DPM) code together with deformable image registration based on the NCAT deformation field were used to find a composite dose distribution for each phantom. These composite distributions were subsequently analyzed using information from the dose volume histograms (DVH). Lesion motion amplitude has the largest effect on the dose distribution. Tumor size was found to have a smaller effect and can be mitigated by ensuring the planning constraints are optimized for the tumor size. The use of a dynamic or heterogeneous lung density model over a respiratory cycle does not appear to be an important factor with a ≤ 0.6% change in the mean dose received by the ITV, PTV and right lung. The heterogeneous model increases the realism of the NCAT phantom and may provide more accurate simulations in radiation therapy

  5. WORRIED SICK? WORKER RESPONSES TO ORGANIZATIONAL TURMOIL

    OpenAIRE

    Bratberg, Espen; Monstad, Karin

    2012-01-01

    Sickness absence has risen over the past years in Norway. One explanation put forward is that a tougher labor market represents a health hazard, while a competing hypothesis predicts that loss of job security works as a disciplinary device. In this analysis we aim to trace a causal impact of organizational turmoil or job insecurity on sickness absence, applying a difference-in-difference approach. Utilizing a negative financial shock that hit specific employers and workplaces, we find that si...

  6. [Sickness absence associated with major life events].

    Science.gov (United States)

    Markussen, Simen; Røgeberg, Ole

    2012-05-29

    Sickness absence in the Norwegian workplace doubled in the period 1993-2003. However, the extent to which the driving factors were medical or non-medical remains unclear, as does the extent to which the cause may be found in the composition of the workforce. A differences-in-differences regression model was used to estimate the added sickness absence associated with major life events such as separation, death of spouse and pregnancy in the period 1993-2005. The data were obtained from administrative registers covering the entire Norwegian population, and include all absence periods of 16 days' duration or more reported by a doctor's medical certificate. The primary outcome measures were incidence (the proportion of absentees in a given time window) and absence (the proportion of sick days in a given time window). The level of absence among employees exposed to the specified life events was compared to control groups matched for gender, age, education and income. In 1993, people in each of the three groups exposed to major life events had more frequent and longer periods of absence than people in the control groups. This added sickness absence increased between 1993 and 2005. The changes in added sickness absence were at times significant, particularly for pregnant women. While sickness absence among pregnant women in 1993 was 15.4 percentage points higher than in the control group, the difference had increased to 24.8 percentage points in 2005. We find it improbable for the increase in added sickness absence to be caused by changes in the medical impact of life events or alterations in the workforce composition. We believe the increase is caused by changing attitudes among the working population and in the medical profession towards sickness absence on grounds that are not strictly medical, combined with improved social acceptance and diagnosis of mental health issues, and/or a medicalisation of natural health variations (pregnancy) and emotional distress (grief).

  7. Investigation of the motion of diesel injection jets using high-speed cinematography and short time holography

    International Nuclear Information System (INIS)

    Eisfeld, F.

    1987-01-01

    The knowledge about the penetration of diesel injection jets, particularly about the flow within the short behind the nozzle, and the arising of droplets from an injection jet is very limited. Experimental investigations are required to describe the process of penetration and spreading of the jet. The research method requires high speed cinematography and short time holography. Problems in the investigation method are described

  8. Fever and sickness behavior: Friend or foe?

    Science.gov (United States)

    Harden, L M; Kent, S; Pittman, Q J; Roth, J

    2015-11-01

    Fever has been recognized as an important symptom of disease since ancient times. For many years, fever was treated as a putative life-threatening phenomenon. More recently, it has been recognized as an important part of the body's defense mechanisms; indeed at times it has even been used as a therapeutic agent. The knowledge of the functional role of the central nervous system in the genesis of fever has greatly improved over the last decade. It is clear that the febrile process, which develops in the sick individual, is just one of many brain-controlled sickness symptoms. Not only will the sick individual appear "feverish" but they may also display a range of behavioral changes, such as anorexia, fatigue, loss of interest in usual daily activities, social withdrawal, listlessness or malaise, hyperalgesia, sleep disturbances and cognitive dysfunction, collectively termed "sickness behavior". In this review we consider the issue of whether fever and sickness behaviors are friend or foe during: a critical illness, the common cold or influenza, in pregnancy and in the newborn. Deciding whether these sickness responses are beneficial or harmful will very much shape our approach to the use of antipyretics during illness. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Relative Deprivation and Sickness Absence in Sweden

    Directory of Open Access Journals (Sweden)

    Jonas Helgertz

    2013-08-01

    Full Text Available Background: A high prevalence of sickness absence in many countries, at a substantial societal cost, underlines the importance to understand its determining mechanisms. This study focuses on the link between relative deprivation and the probability of sickness absence. Methods: 184,000 men and women in Sweden were followed between 1982 and 2001. The sample consists of working individuals between the ages of 19 and 65. The outcome is defined as experiencing more than 14 days of sickness absence during a year. Based on the complete Swedish population, an individual’s degree of relative deprivation is measured through income compared to individuals of the same age, sex, educational level and type. In accounting for the possibility that sickness absence and socioeconomic status are determined by common factors, discrete-time duration models were estimated, accounting for unobserved heterogeneity through random effects. Results: The results confirm that the failure to account for the dynamics of the individual’s career biases the influence from socioeconomic characteristics. Results consistently suggest a major influence from relative deprivation, with a consistently lower risk of sickness absence among the highly educated. Conclusions: Altering individual’s health behavior through education appears more efficient in reducing the reliance on sickness absence, rather than redistributive policies.

  10. Relative deprivation and sickness absence in Sweden.

    Science.gov (United States)

    Helgertz, Jonas; Hess, Wolfgang; Scott, Kirk

    2013-08-29

    A high prevalence of sickness absence in many countries, at a substantial societal cost, underlines the importance to understand its determining mechanisms. This study focuses on the link between relative deprivation and the probability of sickness absence. 184,000 men and women in Sweden were followed between 1982 and 2001. The sample consists of working individuals between the ages of 19 and 65. The outcome is defined as experiencing more than 14 days of sickness absence during a year. Based on the complete Swedish population, an individual's degree of relative deprivation is measured through income compared to individuals of the same age, sex, educational level and type. In accounting for the possibility that sickness absence and socioeconomic status are determined by common factors, discrete-time duration models were estimated, accounting for unobserved heterogeneity through random effects. The results confirm that the failure to account for the dynamics of the individual's career biases the influence from socioeconomic characteristics. Results consistently suggest a major influence from relative deprivation, with a consistently lower risk of sickness absence among the highly educated. Altering individual's health behavior through education appears more efficient in reducing the reliance on sickness absence, rather than redistributive policies.

  11. Sick leave and disability pension before and after initiation of antirheumatic therapies in clinical practice.

    Science.gov (United States)

    Neovius, M; Simard, J F; Klareskog, L; Askling, J

    2011-08-01

    To investigate sick leave and disability pension in rheumatoid arthritis (RA) in relation to the initiation of biological and non-biological antirheumatic therapies in clinical practice. Patients aged 19-60 years initiating non-biological mono (n=2796) or combination disease-modifying antirheumatic drug (DMARD) therapy (n=973), or biological agents (n=4787) were identified in the Swedish Rheumatology Quality Register between 1999 and 2007. Sick leave and disability pension data (1995-2010) were retrieved from national registers. During the year before the start of mono DMARD, combination DMARD and biological treatment, 10%, 12% and 43% of patients received disability pension benefits, respectively. The corresponding combined annual sick leave and disability pension days were 78 (54+25), 132 (105+27) and 190 (79+111). Irrespective of treatment type, initiators were characterised by a history of increasing sick leave and disability pension. Treatment start was associated with a break in this trajectory: sick leave decreased while disability pension increased, resulting in a net stabilisation of total days. Higher levels of days on sick leave and disability pension at treatment start were observed in patients initiating biologics in 1999 (236 days/year) compared with 2007 (150 days/year; ppension increased rapidly before the initiation of antirheumatic therapy, which was associated with a halt but not a reversal of this development. Work ability is a metric of importance for clinical practice, signalling large remaining needs in the RA population, and the need for intervention earlier in the disease process.

  12. Sickness absence and disability pension following breast cancer - A population-based matched cohort study.

    Science.gov (United States)

    Lundh, Marie Høyer; Lampic, Claudia; Nordin, Karin; Ahlgren, Johan; Bergkvist, Leif; Lambe, Mats; Berglund, Anders; Johansson, Birgitta

    2014-12-01

    To compare sickness absence and disability pension in a population-based cohort of women with breast cancer (n = 463) from 1 year pre-diagnosis until 3 years post-diagnosis with a matched control group (n = 2310), and to investigate predictors of sickness absence during the 2nd and 3rd year post-diagnosis. Following breast cancer, the proportion of disease-free women with sickness absence decreased post-diagnosis (1st-3rd year; 78%-31%-19%), but did not reach the pre-diagnostic level (14%; P pension post-diagnosis (P > 0.05). Among patients, chemotherapy, baseline fatigue and pre-diagnosis sick days predicted sickness absence during the 2nd, 3rd, and 2nd and 3rd year post-diagnosis, respectively (P < 0.05). Breast cancer is associated with increased sickness absence 3 years post-diagnosis. In a clinical setting, prevention and treatment of side effects are important in reducing long-term consequences. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Leading during change: the effects of leader behavior on sickness absence in a Norwegian health trust.

    Science.gov (United States)

    Bernstrøm, Vilde Hoff; Kjekshus, Lars Erik

    2012-09-17

    Organizational change often leads to negative employee outcomes such as increased absence. Because change is also often inevitable, it is important to know how these negative outcomes could be reduced. This study investigates how the line manager's behavior relates to sickness absence in a Norwegian health trust during major restructuring. Leader behavior was measured by questionnaire, where employees assessed their line manager's behavior (N = 1008; response rate 40%). Data on sickness absence were provided at department level (N = 35) and were measured at two times. Analyses were primarily conducted using linear regression; leader behavior was aggregated and weighted by department size. The results show a relationship between several leader behaviors and sickness absence. The line managers' display of loyalty to their superiors was related to higher sickness absence; whereas task monitoring was related to lower absence. Social support was related to higher sickness absence. However, the effect of social support was no longer significant when the line manager also displayed high levels of problem confrontation. The findings clearly support the line manager's importance for employee sickness absence during organizational change. We conclude that more awareness concerning the manager's role in change processes is needed.

  14. The Prognostic Value of the Work Ability Index for Sickness Absence among Office Workers.

    Directory of Open Access Journals (Sweden)

    Kerstin G Reeuwijk

    Full Text Available The work ability index (WAI is a frequently used tool in occupational health to identify workers at risk for a reduced work performance and for work-related disability. However, information about the prognostic value of the WAI to identify workers at risk for sickness absence is scarce.To investigate the prognostic value of the WAI for sickness absence, and whether the discriminative ability differs across demographic subgroups.At baseline, the WAI (score 7-49 was assessed among 1,331 office workers from a Dutch financial service company. Sickness absence was registered during 12-months follow-up and categorised as 0 days, 0sickness absence were estimated by multinomial regression analyses. Discriminative ability of the WAI was assessed by the Area Under the Curve (AUC and Ordinal c-index (ORC. Test characteristics were determined for dichotomised outcomes. Additional analyses were performed for separate WAI dimensions, and subgroup analyses for demographic groups.A lower WAI was associated with sickness absence (≥15 days vs. 0 days: per point lower WAI score OR=1.27; 95%CI 1.21-1.33. The WAI showed reasonable ability to discriminate between categories of sickness absence (ORC=0.65; 95%CI 0.63-0.68. Highest discrimination was found for comparing workers with ≥15 sick days with 0 sick days (AUC=0.77 or with 1-5 sick days (AUC=0.69. At the cut-off for poor work ability (WAI≤27 the sensitivity to identify workers at risk for ≥15 sick days was 7.5%, the specificity 99.6%, and the positive predictive value 82%. The performance was similar across demographic subgroups.The WAI could be used to identify workers at high risk for prolonged sickness absence. However, due to low sensitivity many workers will be missed. Hence, additional factors are required to better identify workers at highest risk.

  15. Does Postponement of First Pregnancy Increase Gender Differences in Sickness Absence? A Register Based Analysis of Norwegian Employees in 1993–2007

    Science.gov (United States)

    Ariansen, Anja M. S.; Mykletun, Arnstein

    2014-01-01

    Background From 1970–2012, the average age at first delivery increased from 23.2–28.5 in Norway. Postponement of first pregnancy increases risks of medical complications both during and after pregnancy. Sickness absence during pregnancy has over the last two decades increased considerably more than in non-pregnant women. The aim of this paper is twofold: Firstly to investigate if postponement of pregnancy is related to increased sickness absence and thus contributing to the increased gender difference in sickness absence; and secondly, to estimate how much of the increased gender difference in sickness absence that can be accounted for by increased sickness absence amongst pregnant women. Methods We employed registry-data to analyse sickness absence among all Norwegian employees with income equivalent to full-time work in the period 1993–2007. Results After control for age, education, and income, pregnant women's sickness absence (age 20–44) increased on average 0.94 percentage points each year, compared to 0.29 in non-pregnant women and 0.14 in men. In pregnant women aged 20–24, sickness absence during pregnancy increased by 0.96 percent points per calendar year, compared to 0.60 in age-group 30–34. Sickness absence during pregnancy accounted for 25% of the increased gender gap in sickness absence, accounting for changes in education, income and age. Conclusions Postponement of first pregnancy does not explain the increase in pregnant women's sickness absence during the period 1993–2007 as both the highest level and increase in sickness absence is seen in the younger women. Reasons are poorly understood, but still important as it accounts for 25% of the increased gender gap in sickness absence. PMID:24667483

  16. Prognosis for a sick planet.

    Science.gov (United States)

    Maslin, Mark

    2008-12-01

    Global warming is the most important science issue of the 21st century, challenging the very structure of our global society. The study of past climate has shown that the current global climate system is extremely sensitive to human-induced climate change. The burning of fossil fuels since the beginning of the industrial revolution has already caused changes with clear evidence for a 0.75 degrees C rise in global temperatures and 22 cm rise in sea level during the 20th century. The Intergovernmental Panel on Climate Change synthesis report (2007) predicts that global temperatures by 2100 could rise by between 1.1 degrees C and 6.4 degrees C. Sea level could rise by between 28 cm and 79 cm, more if the melting of the polar ice caps accelerates. In addition, weather patterns will become less predictable and the occurrence of extreme climate events, such as storms, floods, heat waves and droughts, will increase. The potential effects of global warming on human society are devastating. We do, however, already have many of the technological solutions to cure our sick planet.

  17. [Subjective sensations indicating simulator sickness and fatigue after exposure to virtual reality].

    Science.gov (United States)

    Malińska, Marzena; Zuzewicz, Krystyna; Bugajska, Joanna; Grabowski, Andrzej

    2014-01-01

    The study assessed the incidence and intensity of subjective symptoms indicating simulator sickness among the persons with no inclination to motion sickness, immersed in virtual reality (VR) by watching an hour long movie in the stereoscopic (three-dimensional - 3D) and non-stereoscopic (two-dimensional - 2D) versions and after an hour long training using virtual reality, called sVR. The sample comprised 20 healthy young men with no inclination to motion sickness. The participants' subjective sensations, indicating symptoms of simulator sickness were assessed using the questionnaire completed by the participants immediately, 20 min and 24 h following the test. Grandjean's scale was used to assess fatigue and mood. The symptoms were observed immediately after the exposure to sVR. Their intensity was higher than after watching the 2D and 3D movies. A significant relationship was found between the eye pain and the type of exposure (2D, 3D and sVR) (Chi2)(2) = 6.225, p < or = 0.05); the relationship between excessive perspiration and the exposure to 31) movie and sVR was also noted (Chi2(1) = 9.173, p < or = 0.01). Some symptoms were still observed 20 min after exposure to sVR. The comparison of Grandjean's scale results before and after the training in sVR handing showed significant differences in 11 out of 14 subscales. Before and after exposure to 3D movie, the differences were significant only for the "tired-fatigued" subscale (Z = 2.501, p < or = 0.012) in favor of "fatigued". Based on the subjective sensation of discomfort after watching 2D and 3D movies it is impossible to predict symptoms of simulator sickness after training using sVR.

  18. Current status of ground motions evaluation in seismic design guide for nuclear power facilities. Investigation on IAEA and US.NRC

    International Nuclear Information System (INIS)

    Nakajima, Masato; Ito, Hiroshi; Hirata, Kazuta

    2009-01-01

    Recently, IAEA (International Atomic Energy Agency) and US.NRC (US. Nuclear Regulatory Commission) published several standards and technical reports on seismic design and safety evaluation for nuclear power facilities. This report summarizes the current status of the international guidelines on seismic design and safety evaluation for nuclear power facilities in order to explore the future research topics. The main results obtained are as follows: 1 IAEA: (1) In the safety standard series, two levels are defined as seismic design levels, and design earthquake ground motion is determined corresponding to each seismic design level. (2) A new framework on seismic design which consists of conventional deterministic method and risk-based method is discussed in the technical report although the framework is not adopted in the safety guidelines. 2 USA: (1) US.NRC discusses a performance-based seismic design framework which has been originally developed by the private organization (American Society of Civil Engineers). (2) Design earthquakes and earthquake ground motion are mainly evaluated and determined based on probabilistic seismic hazard evaluations. 3 Future works: It should be emphasized that IAEA and US.NRC have investigated the implementation of risk-based concept into seismic design. The implementation of risk-based concept into regulation and seismic design makes it possible to consider various uncertainties and to improve accountability. Therefore, we need to develop the methods for evaluating seismic risk of structures, and to correlate seismic margin and seismic risk quantitatively. Moreover, the probabilistic method of earthquake ground motions, that is required in the risk-based design, should be applied to sites in Japan. (author)

  19. Low job satisfaction does not identify nurses at risk of future sickness absence: results from a Norwegian cohort study.

    Science.gov (United States)

    Roelen, C A M; Magerøy, N; van Rhenen, W; Groothoff, J W; van der Klink, J J L; Pallesen, S; Bjorvatn, B; Moen, B E

    2013-03-01

    Sickness absence is high in healthcare and contributes to nursing staff shortages reducing the efficiency and quality of patient care. Assessing the risk of sickness absence in working nurses opens opportunities for preventive strategies. Job satisfaction has attracted much attention in healthcare research and has been associated with sickness absence among nurses. To investigate if job satisfaction scores are useful to identify working nurses at risk of future sickness absence. Prospective cohort study with a baseline period from November 2008 to March 2009 and 1-year follow-up. Hospitals, nursing homes, and ambulant care settings in Norway. 2059 Norwegian nurses, of whom 1582 (77%) could be followed-up. Nurses received a questionnaire at baseline and after 1-year follow-up. The questionnaire contained the Job Satisfaction Index (JSI), a 5-item scale measuring overall job satisfaction, and asked for sickness absence in the last 12 months. Baseline JSI scores were included in a logistic regression model with self-rated sickness absence at 1-year follow-up as outcome variable. Predictions of sickness absence were calibrated by the Hosmer-Lemeshow goodness-of-fit test. The ability of JSI scores to discriminate between nurses with and without sickness absence was examined by receiver operating characteristic analysis and expressed as area under the curve (AUC). Low job satisfaction was associated with higher odds of sickness absence (odds ratio [OR]=1.05; 95% confidence interval [CI] 1.01-1.09) and high (≥ 31 days) sickness absence (OR=1.10; 95% CI 1.06-1.14). Calibration was acceptable, but job satisfaction neither discriminated between nurses with and without sickness absence (AUC=0.54; 95% CI 0.51-0.58) nor between nurses with and without high (≥ 31 days) sickness absence (AUC=0.58; 95% CI 0.54-0.63). The results of this study indicated that job satisfaction was associated with sickness absence, though job satisfaction scores as measured with the JSI did not

  20. Visual-vestibular integration motion perception reporting

    Science.gov (United States)

    Harm, Deborah L.; Reschke, Millard R.; Parker, Donald E.

    1999-01-01

    Self-orientation and self/surround-motion perception derive from a multimodal sensory process that integrates information from the eyes, vestibular apparatus, proprioceptive and somatosensory receptors. Results from short and long duration spaceflight investigations indicate that: (1) perceptual and sensorimotor function was disrupted during the initial exposure to microgravity and gradually improved over hours to days (individuals adapt), (2) the presence and/or absence of information from different sensory modalities differentially affected the perception of orientation, self-motion and surround-motion, (3) perceptual and sensorimotor function was initially disrupted upon return to Earth-normal gravity and gradually recovered to preflight levels (individuals readapt), and (4) the longer the exposure to microgravity, the more complete the adaptation, the more profound the postflight disturbances, and the longer the recovery period to preflight levels. While much has been learned about perceptual and sensorimotor reactions and adaptation to microgravity, there is much remaining to be learned about the mechanisms underlying the adaptive changes, and about how intersensory interactions affect perceptual and sensorimotor function during voluntary movements. During space flight, SMS and perceptual disturbances have led to reductions in performance efficiency and sense of well-being. During entry and immediately after landing, such disturbances could have a serious impact on the ability of the commander to land the Orbiter and on the ability of all crew members to egress from the Orbiter, particularly in a non-nominal condition or following extended stays in microgravity. An understanding of spatial orientation and motion perception is essential for developing countermeasures for Space Motion Sickness (SMS) and perceptual disturbances during spaceflight and upon return to Earth. Countermeasures for optimal performance in flight and a successful return to Earth require

  1. The association between body mass index status and sick leave and the role of emotional exhaustion-a mediation analysis among a representative sample of dutch employees.

    Science.gov (United States)

    Proper, Karin I; Koppes, Lando L J; Meijer, Sanne; Bemelmans, Wanda J E

    2013-10-01

    To investigate the associations between body mass index (BMI) and sick leave, and the mediating role of emotional exhaustion. Data were collected from a large survey among Dutch employees (n = 35,022). The causal pathway approach consisting of four regression analyses was applied. In women, moderate overweight and obesity were associated with higher sick leave; in men, obesity, but not moderate overweight, was associated with higher sick leave. Obese workers were at increased risk for emotional exhaustion. Emotional exhaustion was also associated with higher sick leave rates. Adjustment for emotional exhaustion in the association between BMI and sick leave hardly changed the effect size and significance remained. The association between BMI status and sick leave can be explained partially by the presence of emotional exhaustion. Workplace health promotion initiatives should take this into account.

  2. Gender and age differences in the recurrence of sickness absence due to common mental disorders: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Bültmann Ute

    2010-07-01

    Full Text Available Abstract Background Common mental disorders (CMDs are an important cause of sickness absence and long-term work disability. Although CMDs are known to have high recurrence rates, little is known about the recurrence of sickness absence due to CMDs. The aim of this study was to investigate the recurrence of sickness absence due to CMDs, including distress, adjustment disorders, depressive disorders and anxiety disorders, according to age, in male and female employees in the Netherlands. Methods Data on sickness absence episodes due to CMDs were obtained for 137,172 employees working in the Dutch Post and Telecommunication companies between 2001 and 2007. The incidence density (ID and recurrence density (RD of sickness absence due to CMDs was calculated per 1000 person-years in men and women in the age-groups of Results The ID of one episode of CMDs sickness absence was 25.0 per 1000 person-years, and the RD was 76.7 per 1000 person-years. Sickness absence due to psychiatric disorders (anxiety and depression does not have a higher recurrence density of sickness absence due to any CMDs as compared to stress-related disorders (distress and adjustment disorders: 81.6 versus 76.0 per 1000 person-years. The ID of sickness absence due to CMDs was higher in women than in men, but the RD was similar. Recurrences were more frequent in women Conclusions Employees who have been absent from work due to CMDs are at increased risk of recurrent sickness absence due to CMDs and should be monitored after they return to work. The RD was similar in men and in women. In women

  3. Driving simulator sickness: Impact on driving performance, influence of blood alcohol concentration, and effect of repeated simulator exposures.

    Science.gov (United States)

    Helland, Arne; Lydersen, Stian; Lervåg, Lone-Eirin; Jenssen, Gunnar D; Mørland, Jørg; Slørdal, Lars

    2016-09-01

    Simulator sickness is a major obstacle to the use of driving simulators for research, training and driver assessment purposes. The purpose of the present study was to investigate the possible influence of simulator sickness on driving performance measures such as standard deviation of lateral position (SDLP), and the effect of alcohol or repeated simulator exposure on the degree of simulator sickness. Twenty healthy male volunteers underwent three simulated driving trials of 1h's duration with a curvy rural road scenario, and rated their degree of simulator sickness after each trial. Subjects drove sober and with blood alcohol concentrations (BAC) of approx. 0.5g/L and 0.9g/L in a randomized order. Simulator sickness score (SSS) did not influence the primary outcome measure SDLP. Higher SSS significantly predicted lower average speed and frequency of steering wheel reversals. These effects seemed to be mitigated by alcohol. Higher BAC significantly predicted lower SSS, suggesting that alcohol inebriation alleviates simulator sickness. The negative relation between the number of previous exposures to the simulator and SSS was not statistically significant, but is consistent with habituation to the sickness-inducing effects, as shown in other studies. Overall, the results suggest no influence of simulator sickness on SDLP or several other driving performance measures. However, simulator sickness seems to cause test subjects to drive more carefully, with lower average speed and fewer steering wheel reversals, hampering the interpretation of these outcomes as measures of driving impairment and safety. BAC and repeated simulator exposures may act as confounding variables by influencing the degree of simulator sickness in experimental studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Work-related psychosocial events as triggers of sick leave - results from a Swedish case-crossover study

    Directory of Open Access Journals (Sweden)

    Lindholm Christina

    2011-03-01

    Full Text Available Abstract Background Although illness is an important cause of sick leave, it has also been suggested that non-medical risk factors may influence this association. If such factors impact on the period of decision making, they should be considered as triggers. Yet, there is no empirical support available. The aim was to investigate whether recent exposure to work-related psychosocial events can trigger the decision to report sick when ill. Methods A case-crossover design was applied to 546 sick-leave spells, extracted from a Swedish cohort of 1 430 employees with a 3-12 month follow-up of new sick-leave spells. Exposure in a case period corresponding to an induction period of one or two days was compared with exposure during control periods sampled from workdays during a two-week period prior to sick leave for the same individual. This was done according to the matched-pair interval and the usual frequency approaches. Results are presented as odds ratios (OR with 95% confidence intervals (CI. Results Most sick-leave spells happened in relation to acute, minor illnesses that substantially reduced work ability. The risk of taking sick leave was increased when individuals had recently been exposed to problems in their relationship with a superior (OR 3.63; CI 1.44-9.14 or colleagues (OR 4.68; CI 1.43-15.29. Individuals were also more inclined to report sick on days when they expected a very stressful work situation than on a day when they were not under such stress (OR 2.27; CI 1.40-3.70. Conclusions Exposure to problems in workplace relationships or a stressful work situation seems to be able to trigger reporting sick. Psychosocial work-environmental factors appear to have a short-term effect on individuals when deciding to report sick.

  5. Labour market trajectories following sickness absence due to self-reported all cause morbidity--a longitudinal study.

    Science.gov (United States)

    Pedersen, Pernille; Lund, Thomas; Lindholdt, Louise; Nohr, Ellen A; Jensen, Chris; Søgaard, Hans Jørgen; Labriola, Merete

    2016-04-16

    To investigate differences in return to work (RTW) and employment trajectories in individuals on sick leave for either mental health reasons or other health related reasons. This study was based on 2036 new sickness absence cases who completed a questionnaire on social characteristics, expectations for RTW and reasons for sickness absence. They were divided into two exposure groups according to their self-reported sickness absence reason: mental health reasons or other health reasons. The outcome was employment status during the following 51 weeks and was measured both as time-to-event analysis and with sequence analysis. Individuals with mental health reasons for sickness absence had a higher risk of not having returned to work (RR 0.87 (0.80;0.93)). Adjusting for gender, age, education and employment did not change the estimate, however, after adding RTW expectations to the model, the excess risk was no longer present (RR 1.01 (0.95;1.08)). In relation to the sequence analysis, individuals with mental health related absence had significantly higher odds of being in the sickness absence cluster and significantly lower odds for being in the fast RTW cluster, but when adjusting for RTW expectations, the odds were somewhat attenuated and no longer significant. Employees on sick leave due to self-reported mental health problems spent more weeks in sickness absence and temporary benefits and had a higher risk of not having returned to work within a year compared to employees on sick leave due to other health reasons. The difference could be explained by their lower RTW expectations at baseline. This emphasises the need to develop suitable and specific interventions to facilitate RTW for this group of sickness absentees.

  6. Investigation of the feasibility of an analytical method of accounting for the effects of atmospheric drag on satellite motion

    Science.gov (United States)

    Bozeman, Robert E.

    1987-01-01

    An analytic technique for accounting for the joint effects of Earth oblateness and atmospheric drag on close-Earth satellites is investigated. The technique is analytic in the sense that explicit solutions to the Lagrange planetary equations are given; consequently, no numerical integrations are required in the solution process. The atmospheric density in the technique described is represented by a rotating spherical exponential model with superposed effects of the oblate atmosphere and the diurnal variations. A computer program implementing the process is discussed and sample output is compared with output from program NSEP (Numerical Satellite Ephemeris Program). NSEP uses a numerical integration technique to account for atmospheric drag effects.

  7. Attitudes towards sickness absence and sickness presenteeism in health and care sectors in Norway and Denmark: a qualitative study.

    Science.gov (United States)

    Krane, Line; Larsen, Eva Ladekjær; Nielsen, Claus Vinther; Stapelfeldt, Christina Malmose; Johnsen, Roar; Risør, Mette Bech

    2014-08-27

    In the health and care sector, sickness absence and sickness presenteeism are frequent phenomena and constitute a field in need of exploration. Attitudes towards sickness absence involve also attitudes towards sickness presenteeism, i.e. going to work while sick, confirmed by previous studies. Sickness behavior, reflecting attitudes on work absence, could differ between countries and influence absence rates. But little is known about attitudes towards sickness absence and sickness presenteeism in the health and care sectors in Norway and Denmark. The aim of the present paper is therefore to explore attitudes towards sickness absence and sickness presenteeism among nursing home employees in both countries. Eight focus group discussions (FGDs) were conducted using a semi-structured interview guide, the main attention of which was attitudes towards sickness absence and sickness presenteeism. FGDs were conducted in two nursing homes in Norway and two in Denmark, with different geographic locations: one in a rural area and one in an urban area in each country. FGDs were recorded, transcribed and analyzed using framework analysis to identify major themes and explanatory patterns. Four major significant themes were identified from the FGDs: a) sickness absence and sickness presenteeism, b) acceptable causes of sickness absence, c) job identity, and d) organization of work and physical aspects of the workplace. Our analyses showed that social commitment and loyalty to residents and colleagues was important for sickness absence and sickness presenteeism, as were perceived acceptable and non-acceptable reasons for sickness absence. Organization of work and physical aspects of the workplace were also found to have an influence on attitudes towards sickness absence. The general interpretation of the findings was that attitudes towards sickness absence and sickness presenteeism among nursing home employees were embedded in situational patterns of moral relationships and were

  8. Validation of sick leave measures: self-reported sick leave and sickness benefit data from a Danish national register compared to multiple workplace-registered sick leave spells in a Danish municipality.

    Science.gov (United States)

    Stapelfeldt, Christina Malmose; Jensen, Chris; Andersen, Niels Trolle; Fleten, Nils; Nielsen, Claus Vinther

    2012-08-15

    Previous validation studies of sick leave measures have focused on self-reports. Register-based sick leave data are considered to be valid; however methodological problems may be associated with such data. A Danish national register on sickness benefit (DREAM) has been widely used in sick leave research. On the basis of sick leave records from 3,554 and 2,311 eldercare workers in 14 different workplaces, the aim of this study was to: 1) validate registered sickness benefit data from DREAM against workplace-registered sick leave spells of at least 15 days; 2) validate self-reported sick leave days during one year against workplace-registered sick leave. Agreement between workplace-registered sick leave and DREAM-registered sickness benefit was reported as sensitivities, specificities and positive predictive values. A receiver-operating characteristic curve and a Bland-Altman plot were used to study the concordance with sick leave duration of the first spell. By means of an analysis of agreement between self-reported and workplace-registered sick leave sensitivity and specificity was calculated. Ninety-five percent confidence intervals (95% CI) were used. The probability that registered DREAM data on sickness benefit agrees with workplace-registered sick leave of at least 15 days was 96.7% (95% CI: 95.6-97.6). Specificity was close to 100% (95% CI: 98.3-100). The registered DREAM data on sickness benefit overestimated the duration of sick leave spells by an average of 1.4 (SD: 3.9) weeks. Separate analysis on pregnancy-related sick leave revealed a maximum sensitivity of 20% (95% CI: 4.3-48.1).The sensitivity of self-reporting at least one or at least 56 sick leave day/s was 94.5 (95% CI: 93.4 - 95.5) % and 58.5 (95% CI: 51.1 - 65.6) % respectively. The corresponding specificities were 85.3 (95% CI: 81.4 - 88.6) % and 98.9 (95% CI: 98.3 - 99.3) %. The DREAM register offered valid measures of sick leave spells of at least 15 days among eldercare employees. Pregnancy

  9. Validation of sick leave measures: self-reported sick leave and sickness benefit data from a Danish national register compared to multiple workplace-registered sick leave spells in a Danish municipality

    Directory of Open Access Journals (Sweden)

    Stapelfeldt Christina Malmose

    2012-08-01

    Full Text Available Abstract Background Previous validation studies of sick leave measures have focused on self-reports. Register-based sick leave data are considered to be valid; however methodological problems may be associated with such data. A Danish national register on sickness benefit (DREAM has been widely used in sick leave research. On the basis of sick leave records from 3,554 and 2,311 eldercare workers in 14 different workplaces, the aim of this study was to: 1 validate registered sickness benefit data from DREAM against workplace-registered sick leave spells of at least 15 days; 2 validate self-reported sick leave days during one year against workplace-registered sick leave. Methods Agreement between workplace-registered sick leave and DREAM-registered sickness benefit was reported as sensitivities, specificities and positive predictive values. A receiver-operating characteristic curve and a Bland-Altman plot were used to study the concordance with sick leave duration of the first spell. By means of an analysis of agreement between self-reported and workplace-registered sick leave sensitivity and specificity was calculated. Ninety-five percent confidence intervals (95% CI were used. Results The probability that registered DREAM data on sickness benefit agrees with workplace-registered sick leave of at least 15 days was 96.7% (95% CI: 95.6-97.6. Specificity was close to 100% (95% CI: 98.3-100. The registered DREAM data on sickness benefit overestimated the duration of sick leave spells by an average of 1.4 (SD: 3.9 weeks. Separate analysis on pregnancy-related sick leave revealed a maximum sensitivity of 20% (95% CI: 4.3-48.1. The sensitivity of self-reporting at least one or at least 56 sick leave day/s was 94.5 (95% CI: 93.4 – 95.5 % and 58.5 (95% CI: 51.1 – 65.6 % respectively. The corresponding specificities were 85.3 (95% CI: 81.4 – 88.6 % and 98.9 (95% CI: 98.3 – 99.3 %. Conclusions The DREAM register offered valid measures of sick

  10. Sleeping sickness surveys: game reserve adjacent villages in Malawi

    African Journals Online (AJOL)

    Sleeping sickness surveys: game reserve adjacent villages in Malawi. ... Sera from 160 game ranger volunteers and from 82 suspected cases_of Rhodesian sleeping sickness were tested by use of ELISA, ... AJOL African Journals Online.

  11. Sick leave before and after the age of 65 years among those in paid work in Sweden in 2000 or 2005: a register-based cohort study.

    Science.gov (United States)

    Farrants, Kristin; Kjeldgård, Linnea; Marklund, Staffan; Head, Jenny; Alexanderson, Kristina

    2018-02-01

    Objective With pressure for older people to remain in work, research is needed on how people aged over 65 years fare in the labour market. However, few studies have focused on sick leave among older workers, especially those over the standard retirement age. This study investigated changes in sick-leave patterns among people aged over 65 years still in work. Methods All individuals in Sweden who turned 65 years old in 2000 or 2005 were followed from 1995 to 2010. The mean number of sick-leave days per year was measured for those who remained in paid work past the age of 65 years. Results Those over 65 years still working had fewer sick-leave days before the age of 65 years than those who retired. They also had fewer sick-leave days after 65 years than before. There were fewer socioeconomic differences after 65 years than before, but these differences were greater for workers over 65 years in the 2005 cohort. Conclusions Although there were more people over 65 years in paid work in 2005, sick-leave days and socioeconomic differences in sick leave were lower in this age group. Sick-leave days and socioeconomic differences in sick leave were greater in the 2005 cohort.

  12. Sickness absence in relation to psychosocial work factors among daytime workers in an electric equipment manufacturing company.

    Science.gov (United States)

    Otsuka, Yasumasa; Takahashi, Masaya; Nakata, Akinori; Haratani, Takashi; Kaida, Kosuke; Fukasawa, Kenji; Hanada, Takanobu; Ito, Akiko

    2007-04-01

    Associations between psychosocial work factors and sickness absence were investigated in a cross-sectional study of 833 daytime workers. Participants completed a questionnaire regarding psychosocial work factors using the US National Institute for Occupational Safety and Health Generic Job Stress Questionnaire (job control, quantitative workload, cognitive demands, variance in workload, intragroup conflict, intergroup conflict, supervisor support, coworker support, family support, job satisfaction and depressive symptoms) and the number of days of sickness absence within the previous year. Multivariate analyses of covariance with age and occupation as covariates (MANCOVA) were used to test the relationships between psychosocial work factors and sickness absence stratified by sex. In men, the age-adjusted MANCOVA showed that, quantitative workload was highest in the 0.5-4.5 d of sickness absence group (pjob satisfaction and depressive symptoms) in this group were almost identical to the levels recorded in the no sickness absence group. In contrast, low levels of job control (pjob satisfaction (pjob satisfaction was associated with 5 d or more sickness absence (p<0.10). This study suggests that appropriate use of sickness absence at times of being exposed to high quantitative workload may help male workers to recover from stressful situations.

  13. How to avoid simulation sickness in virtual environments during user displacement

    Science.gov (United States)

    Kemeny, A.; Colombet, F.; Denoual, T.

    2015-03-01

    Driving simulation (DS) and Virtual Reality (VR) share the same technologies for visualization and 3D vision and may use the same technics for head movement tracking. They experience also similar difficulties when rendering the displacements of the observer in virtual environments, especially when these displacements are carried out using driver commands, including steering wheels, joysticks and nomad devices. High values for transport delay, the time lag between the action and the corresponding rendering cues and/or visual-vestibular conflict, due to the discrepancies perceived by the human visual and vestibular systems when driving or displacing using a control device, induces the so-called simulation sickness. While the visual transport delay can be efficiently reduced using high frequency frame rate, the visual-vestibular conflict is inherent to VR, when not using motion platforms. In order to study the impact of displacements on simulation sickness, we have tested various driving scenarios in Renault's 5-sided ultra-high resolution CAVE. First results indicate that low speed displacements with longitudinal and lateral accelerations under a given perception thresholds are well accepted by a large number of users and relatively high values are only accepted by experienced users and induce VR induced symptoms and effects (VRISE) for novice users, with a worst case scenario corresponding to rotational displacements. These results will be used for optimization technics at Arts et Métiers ParisTech for motion sickness reduction in virtual environments for industrial, research, educational or gaming applications.

  14. Risk factors associated with sick leave due to work-related injuries in Dutch farmers: an exploratory case-control study

    NARCIS (Netherlands)

    Hartman, E.; Frankena, K.; Oude Vrielink, H.H.E.; Nielen, M.; Metz, J.H.M.; Huirne, R.B.M.

    2004-01-01

    Using data from an insurance company, the occurrence of sick leave among Dutch farmers due to work-related injuries, and the epidemiological risk factors were investigated. In this case-control study the cases had filed a sick leave claim for work-related injury from 19982001 and the controls had

  15. Workload, work stress, and sickness absence in Swedish male and female white-collar employees.

    Science.gov (United States)

    Krantz, Gunilla; Lundberg, Ulf

    2006-01-01

    This study aimed to analyse, in a homogeneous population of highly educated men and women, gender differences in self-reported sickness absence as related to paid and unpaid work and combinations of these (double exposure), as well as to perceived work stress and work-home conflict, i.e. conflict between demands from the home and work environment. A total of 743 women and 596 men, full-time working white-collar employees randomly selected from the general Swedish population aged 32-58, were assessed by a Swedish total workload instrument. The influence of conditions in paid and unpaid work and combinations of these on self-reported sickness absence was investigated by multivariate regression analyses. Analysis of variance (ANOVA) was used to assess differences between men and women. Overtime was associated with lower sickness absence, not only for men but also for women, and a double-exposure situation did not increase the risk of sick leave. Contrary to what is normally seen, conflict between demands did not emerge as a risk factor for sickness absence for women, but for men. Our assumption that sickness absence patterns would be more similar for white-collar men and women than for the general population was not confirmed. However, the women working most hours were also the least sick-listed and assumed less responsibility for household chores. These women were mainly in top-level positions and therefore we conclude that men and women in these high-level positions seem to share household burdens more evenly, but they can also afford to employ someone to assist in the household.

  16. Trends in sickness absence in Denmark

    DEFF Research Database (Denmark)

    Johansen, Kristina; Bihrmann, Kristine; Mikkelsen, Sigurd

    2009-01-01

    's Authority, and the Labor Force Survey indicated a stable and largely unaltered pattern of sickness absence during the last 20 years. Findings from Statistics Denmark showed an increase in the cumulative incidence proportion from 6.6 to 7.5% among employed people between 2000 and 2007. CONCLUSION: Our data...... a linear regression analysis to analyze time trends in sickness absence based on datasets from the Danish Employers Confederation, the State Employer's Authority, the Labour Force Survey, and Statistics Denmark. RESULTS: The findings from the Confederation of Danish Employers, the State Employer...

  17. Does paternity leave affect mothers’ sickness absence

    OpenAIRE

    Bratberg, Espen; Naz, Ghazala

    2009-01-01

    Female labour force participation is high in Norway but sickness absence rates are higher for women than for men. This may be partly a result of unequal sharing of childcare in the family. In this paper, we consider the effect of paternity leave on sickness absence among women who have recently given birth. We draw on a six-year panel taken from full population data from administrative sources. We find that in the 6% of families where fathers take out leave more than the standard quota (gende...

  18. Air pollution and sick-leaves. A case study using air pollution data from Oslo

    International Nuclear Information System (INIS)

    Hansen, A.C.; Selte, H.K.

    2000-01-01

    During the last decade an increasing amount of studies have investigated the relationship between air pollution and human health effects. In this study we investigate how these effects in turn induce reduced labour productivity in terms of sick-leaves, which is an important factor in assessment of air pollution costs in urban areas. For this purpose we employ a logit model along with data on sick-leaves from a large office in Oslo and different air pollutants. Our results indicate that sick-leaves are significantly associated with particulate matter (PM 1 0), while the associations with SO 2 and NO 2 are more ambiguous. We also try to estimate the induced social costs in terms of lost labour productivity and increased governmental expenditures, although these estimates are more uncertain. 17 refs

  19. Ab initio investigation of ground-states and ionic motion in particular in zirconia-based solid-oxide electrolytes

    International Nuclear Information System (INIS)

    Hirschfeld, Julian Arndt

    2012-01-01

    Electrolytes with high ionic conductivity at lower temperatures are the prerequisite for the success of Solid Oxide Fuel Cells (SOFC). One candidate is doped zirconia. In the past, the electrical resistance of zirconia based SOFC electrolytes has mainly been decreased by reducing its thickness. But there are limits to reducing the thickness and one can say that nowadays the normal ways are basically exhausted to further enhance the conductivity of well-known electrolyte materials. Hence, new approaches need to be found to discover windows of enhanced ionic conductivity. This can be achieved by understanding the quantum-mechanical oxygen transport in unconventional configurations of doped zirconia. Therefore, such an understanding is of fundamental importance. In this thesis two approaches are pursued, the investigation of the strain dependent ionic migration in zirconia based electrolytes and the designing of an electrolyte material structure with enhanced and strongly anisotropic ionic conductivity. The first approach expands the elementary understanding of oxygen migration in oxide lattices. The migration barrier of the oxygen ion jumps in zirconia is determined by applying the Density Functional Theory (DFT) calculations in connection with the Nudged Elastic Band (NEB) method. These computations show an unexpected window of decreased migration barriers at high compressive strains. Similar to other publications a decrease in the migration barrier for expansive strain is observed. But, in addition, a migration barrier decrease under high compressive strains is found beyond a maximal height of the migration barrier. A simple analytic model offers an explanation. The drop of the migration barrier at high compressions originates from the elevation of the ground-state energy. This means: Increasing ground state energies becomes an interesting alternative to facilitate ionic mobility. The second approach is based on the idea, that actually, only in the direction of ion

  20. Ab initio investigation of ground-states and ionic motion in particular in zirconia-based solid-oxide electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Hirschfeld, Julian Arndt

    2012-12-11

    Electrolytes with high ionic conductivity at lower temperatures are the prerequisite for the success of Solid Oxide Fuel Cells (SOFC). One candidate is doped zirconia. In the past, the electrical resistance of zirconia based SOFC electrolytes has mainly been decreased by reducing its thickness. But there are limits to reducing the thickness and one can say that nowadays the normal ways are basically exhausted to further enhance the conductivity of well-known electrolyte materials. Hence, new approaches need to be found to discover windows of enhanced ionic conductivity. This can be achieved by understanding the quantum-mechanical oxygen transport in unconventional configurations of doped zirconia. Therefore, such an understanding is of fundamental importance. In this thesis two approaches are pursued, the investigation of the strain dependent ionic migration in zirconia based electrolytes and the designing of an electrolyte material structure with enhanced and strongly anisotropic ionic conductivity. The first approach expands the elementary understanding of oxygen migration in oxide lattices. The migration barrier of the oxygen ion jumps in zirconia is determined by applying the Density Functional Theory (DFT) calculations in connection with the Nudged Elastic Band (NEB) method. These computations show an unexpected window of decreased migration barriers at high compressive strains. Similar to other publications a decrease in the migration barrier for expansive strain is observed. But, in addition, a migration barrier decrease under high compressive strains is found beyond a maximal height of the migration barrier. A simple analytic model offers an explanation. The drop of the migration barrier at high compressions originates from the elevation of the ground-state energy. This means: Increasing ground state energies becomes an interesting alternative to facilitate ionic mobility. The second approach is based on the idea, that actually, only in the direction of ion

  1. Is part-time sick leave helping the unemployed?

    OpenAIRE

    Andrén, Daniela

    2011-01-01

    Using a discrete choice one-factor model, we estimate mean treatment parameters and distributional treatment parameters to analyze the effects of degree of sick leave on the probability of full recovery of lost work capacity for employed and unemployed individuals, respectively. Our results indicate that one year after the sick leave spell started, the average potential impact of part-time sick listing on an individual randomly chosen from the population on sick leave was positive for both gr...

  2. Determinants of sick-leave duration : A tool for managers?

    NARCIS (Netherlands)

    Flach, P.A.; Krol, B.; Groothoff, J.W.

    AIMS: To provide managers with tools to manage episodes of sick-leave of their employees, the influence of factors such as age, gender, duration of tenure, working full-time or part-time, cause and history of sick-leave, salary and education on sick-leave duration was studied. METHOD: In a

  3. How Safe Is Measles Immunization Of Sick Children? | Ogbonna ...

    African Journals Online (AJOL)

    A prospective study to ascertain how safe is maeales immunization of sick children was carried out in Jos University Teaching Hospital, Family Health Centre. Out of 125 children who were vaccinated against measles 17(16%) were sick at the time of vaccination. Two (12%) of the sick children had post vaccination reaction.

  4. Reliability of sickness certificates in detecting potential sick leave reduction by modifying working conditions: a clinical epidemiology study

    Directory of Open Access Journals (Sweden)

    Johnsen Roar

    2004-03-01

    Full Text Available Abstract Background Medical sickness certificates are generally the main source for information when scrutinizing the need for aimed intervention strategies to avoid or reduce the individual and community side effects of sick leave. This study explored the value of medical sickness certificates related to daily work in Norwegian National Insurance Offices to identify sick-listed persons, where modified working conditions might reduce the ongoing sick leave. Methods The potential for reducing the ongoing sick leave by modifying working conditions was individually assessed on routine sickness certificates in 999 consecutive sick leave episodes by four Norwegian National Insurance collaborators, two with and two without formal medical competence. The study took place in Northern Norway in 1997 and 1998. Agreement analysed with differences against mean, kappa, and proportional-agreement analysis within and between groups of assessors was used in the judgement. Agreements between the assessors and the self-assessment of sick-listed subjects were additionally analysed in 159 sick-leave episodes. Results Both sick-listed subjects and National Insurance collaborators anticipated a potential reduction in sick leave in 20–30% of cases, and in another 20% the potential was assessed as possible. The chance corrected agreements, however, were poor (k Conclusion Information in medical sickness certificates proved ineffective in detecting cases where modified working conditions may reduce sick leave, and focusing on medical certificates may prevent identification of needed interventions. Strategies on how to communicate directly with sick-listed subjects would enable social authorities to exploit more of the sick leave reduction potential by modifying the working conditions than strategies on improving medical information.

  5. Circadian-Time Sickness: Time-of-Day Cue-Conflicts Directly Affect Health.

    Science.gov (United States)

    van Ee, Raymond; Van de Cruys, Sander; Schlangen, Luc J M; Vlaskamp, Björn N S

    2016-11-01

    A daily rhythm that is not in synchrony with the environmental light-dark cycle (as in jetlag and shift work) is known to affect mood and health through an as yet unresolved neural mechanism. Here, we combine Bayesian probabilistic 'cue-conflict' theory with known physiology of the biological clock of the brain, entailing the insight that, for a functional pacemaker, it is sufficient to have two interacting units (reflecting environmental and internal time-of-day cues), without the need for an extra homuncular directing unit. Unnatural light-dark cycles cause a time-of-day cue-conflict that is reflected by a desynchronization between the ventral (environmental) and dorsal (internal) pacemaking signals of the pacemaker. We argue that this desynchronization, in-and-of-itself, produces health issues that we designate as 'circadian-time sickness', analogous to 'motion sickness'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Introducing Motivational Interviewing in a Sickness Insurance Context: Translation and Implementation Challenges.

    Science.gov (United States)

    Ståhl, Christian; Gustavsson, Maria

    2018-06-01

    Purpose Motivational interviewing (MI) is a conversational method to support clients in need of behavioral change. In an organizational reform, most Swedish sickness insurance officials were trained in MI to promote clients' return to work (RTW) after sick leave. The aim of this article is to investigate experiences of introducing MI as a tool to promote clients' RTW within a sickness insurance context, with special focus on the translation and implementation of the method. Methods A qualitative approach, comprising 69 interviews with officials, managers, and regional coordinators on two occasions. The material was analyzed through qualitative content analysis. Results Officials were positive about MI, but the application was limited to using certain tools with extensive individual variation. Officials struggled with translating MI into a sickness insurance context, where the implementation strategy largely failed to offer adequate support, due to low managerial priority, competing initiatives, and a high workload. Results of the educational intervention could therefore be seen on an individual but not an organizational level. Conclusions In order to translate MI into a sickness insurance context, training needs to be supported by organizational approaches that promote collective learning and sharing of experiences among officials. The results also illustrate how a method cannot be assumed to be implemented simply because training has been provided. Consequently, the application of the method needs to be carefully monitored in studies of interventions where MI is claimed to be used, in order to measure its effectiveness.

  7. Cerebral blood flow in acute mountain sickness

    DEFF Research Database (Denmark)

    Jensen, J B; Wright, Anne; Lassen, N A

    1990-01-01

    Changes in cerebral blood flow (CBF) were measured using the radioactive xenon technique and were related to the development of acute mountain sickness (AMS). In 12 subjects, ascending from 150 to 3,475 m, CBF was 24% increased at 24 h [45.1 to 55.9 initial slope index (ISI) units] and 4% increased...

  8. [The sick individual as a concept].

    Science.gov (United States)

    Tejerizo López, Luis Carlos

    2011-01-01

    We start from the premise, shared by some current philosophical movements and by the author, which states that philosophy is not contemplation, or reflection, or introspection or communication. Philosophy is the art of shaping, inventing and creating concepts. It is an explicit way of introducing new differences in life, a different reading level, a specific jargon, which may imply revealing the flip side of the coin, or a dissimilar view of the side facing us. The philosopher is the friend of the concept, he holds it in his power, which means, basically and in all honesty, that philosophy is the discipline of creating concepts. Let us remember the brilliant idea of the Russian director Tarkovsky, who announced his greatest ambition as an artist: "To capture time". At the same time, we must recall one of the sayings of this director: "Every film I have directed and I intend to direct is always tied to characters who have something to overcome". The healthy individual lives in a specific time, with precise coordinates, aware that his life consists only of living that time. That is, living as defined by Josep María Esquirol: "Then we could also see that the best way of living the present is not to run after the fleeing time, but to see and live the opportunity that appears before us". One of the many circumstances that can intercept the way we see and live the opportunity that appears before us is sickness, one of those inescapable experiences we have not been taught how to pay an adequate attention to, and the meaning of which can, in a way, go unnoticed. As "time" goes by, the circumstance that we consider to be the basis on which existence is founded, sickness can appear, thus introducing a new dimension in the time of the healthy individual. For this reason we, as doctors and professionals, know that sickness "is tied to characters who have something to overcome". In view of the fact that a sickness invades a healthy individual and transforms him into a sick one

  9. Sick Leave and Factors Influencing Sick Leave in Adult Patients with Atopic Dermatitis : A Cross-Sectional Study

    NARCIS (Netherlands)

    van Os-Medendorp, Harmieke; Appelman-Noordermeer, Simone; Bruijnzeel-Koomen, Carla A.F.M.; de Bruin-Weller, MS

    2015-01-01

    BACKGROUND: Little is known about the prevalence of sick leave due to atopic dermatitis (AD). The current literature on factors influencing sick leave is mostly derived from other chronic inflammatory diseases. This study aimed to determine the prevalence of sick leave due to AD and to identify

  10. Part-Time Sick Leave as a Treatment Method?

    OpenAIRE

    Andrén D; Andrén T

    2009-01-01

    This paper analyzes the effects of being on part-time sick leave compared to full-time sick leave on the probability of recovering (i.e., returning to work with full recovery of lost work capacity). Using a discrete choice one-factor model, we estimate mean treatment parameters and distributional treatment parameters from a common set of structural parameters. Our results show that part-time sick leave increases the likelihood of recovering and dominates full-time sick leave for sickness spel...

  11. Changes in drinking as predictors of changes in sickness absence: a case-crossover study.

    Science.gov (United States)

    Ervasti, Jenni; Kivimäki, Mika; Pentti, Jaana; Halonen, Jaana I; Vahtera, Jussi; Virtanen, Marianna

    2018-01-01

    We investigated whether changes in alcohol use predict changes in the risk of sickness absence in a case-crossover design. Finnish public sector employees were surveyed in 2000, 2004 and 2008 on alcohol use and covariates. Heavy drinking was defined as either a weekly intake that exceeded recommendations (12 units for women; 23 for men) or having an extreme drinking session. The responses were linked to national sickness absence registers. We analysed the within-person relative risk of change in the risk of sickness absence in relation to change in drinking. Case period refers to being sickness absent within 1 year of the survey and control period refers to not being sickness absent within 1 year of the survey. Periods of heavy drinking were associated with increased odds of self-certified short-term (1-3 days) sickness absence (multivariable-adjusted OR 1.21, 95% CI 1.07 to 1.38 for all participants; 1.62, 95% CI 1.19 to 2.21 for men and 1.15, 95% CI 1.00 to 1.33 for women). A higher risk of short-term sickness absence was also observed after increase in drinking (OR=1.27, 95% CI 1.07 to 1.52) and a lower risk was observed after decrease in drinking (OR=0.83, 95% CI 0.69 to 1.00). Both increase (OR=1.38, 95% CI 1.21 to 1.57) and decrease (OR=1.27, 95% CI 1.19 to 1.43) in drinking were associated with increased risk of long-term (>9 days) medically certified all-cause sickness absence. Increase in drinking was related to increases in short-term and long-term sickness absences. Men and employees with a low socioeconomic position in particular seemed to be at risk. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  12. 0156 Predictors of sickness absence in pregnancy - a Danish cohort study

    DEFF Research Database (Denmark)

    Lausten Hansen, Mette; Marie Thulstrup, Ane; Kolding Kristensen, Jette

    2014-01-01

    OBJECTIVES: To investigate if parity, fertility treatment, body mass index (BMI), time to pregnancy (TTP), and engagement in physical exercise are risk factors for sickness absence during pregnancy weeks 10 to 30. METHOD: We use data from The Danish National Birth Cohort (DNBC) and the Danish...... and health. We excluded women, who were no longer pregnant at the time of the interview, were unemployed, multiple pregnant or had an obstetrical event within one year before the DNBC pregnancy. This resulted in a study population of 65 047 pregnancies. Outcome data were retrieved from DREAM, which contains...... information on sickness absence on a weekly basis. Data will be analysed using multivariate logistic regression models. RESULTS: Mean age of the participants was 30.5 years, 46% were nulliparous, 6.3% received fertility treatment, mean BMI was 23.6 kg/m(2). Prevalence of sickness absence until pregnancy week...

  13. Effect of Rheumatoid Arthritis on Longterm Sickness Absence in 1994-2011

    DEFF Research Database (Denmark)

    Hansen, Sofie Mandrup; Hetland, Merete Lund; Pedersen, Jacob

    2016-01-01

    Objective. By linkage of national registries, we investigated the risk of longterm sickness absence (LTSA) ≥ 3 weeks in a large cohort of Danish patients with rheumatoid arthritis (RA) and non-patients. The study aimed to (1) estimate the risk of LTSA for patients with RA compared with the general...

  14. Does hospital discharge policy influence sick-leave patterns in the case of female breast cancer?

    DEFF Research Database (Denmark)

    Lindqvist, Rikard; Stenbeck, Magnus; Diderichsen, Finn

    2005-01-01

    in 2000 were selected from the National Cancer Register and combined with data from the sick-leave database of the National Social Insurance Board and the National Hospital Discharge Register (N = 1834). A multi-factorial model was fitted to the data to investigate how differences in hospital care...

  15. Psychosocial work environment and mental health-related long-term sickness absence among nurses

    NARCIS (Netherlands)

    Roelen, Corné A.M.; van Hoffen, Marieke F.A.; Waage, Siri; Schaufeli, Wilmar B.; Twisk, Jos W R; Bjorvatn, Bjørn; Moen, Bente E.; Pallesen, Ståle

    Purpose: We investigated which job demands and job resources were predictive of mental health-related long-term sickness absence (LTSA) in nurses. Methods: The data of 2059 nurses were obtained from the Norwegian survey of Shift work, Sleep and Health. Job demands (psychological demands, role

  16. Exposure to disturbing noise and risk of long-term sickness absence among office workers:

    DEFF Research Database (Denmark)

    Clausen, Thomas; Kristiansen, Jesper; Vinsløv Hansen, Jørgen

    2013-01-01

    Purpose To investigate the association between selfreported exposure to disturbing noise and risk of long-term sickness absence (LTSA) for more than two consecutive weeks among office workers. Methods LTSA was measured using register data that were linked to survey data from 2,883 office workers ...

  17. High physical and psychological load at work and sickness absence due to neck pain

    NARCIS (Netherlands)

    Ariëns, G.A.M.; Bongers, P.M.; Hoogendoorn, W.E.; Wal, G. van der; Mechelen, W. van

    2002-01-01

    Objectives This study investigates the relationship between physical and psychosocial load at work and sickness absence due to neck pain. Methods A prospective cohort study with a follow-up period of 3 years (1994-1998) was performed among a working population. At the beginning of the study,

  18. Psychosocial work conditions and registered sickness absence : a 3-year prospective cohort study among office employees

    NARCIS (Netherlands)

    Roelen, C. A. M.; Koopmans, P. C.; Bultmann, U.; Groothoff, J. W.; van der Klink, J. J. L.

    2009-01-01

    Purpose To investigate associations between a wide variety of psychosocial work conditions and sickness absence in a medium-sized company. Methods Prospective cohort study of 395 employees working in an insurance office. Self-reported psychosocial work conditions were measured by questionnaire in

  19. Concepts of Health and Sickness of Preschool and School Aged Children.

    Science.gov (United States)

    Banks, Ellen

    An investigation was made of children's factual knowledge of health-related concepts and the cognitive implications of their answers to questionnaire items such as "What makes a person sick?", "What is medicine?", and "Do you know what a germ is?" Participants were 80 healthy children between approximately 3 and 15 years of age. An additional 61…

  20. Sickness and death : Economic consequences and coping strategies of the urban poor in Bangladesh

    NARCIS (Netherlands)

    F.U. Khan (Farid U.); Arjun S. Bedi; R.A. Sparrow (Robert)

    2014-01-01

    textabstractThis paper investigates the economic consequences of sickness and death and the manner in which poor urban households in Bangladesh respond to such events. Based on longitudinal data we assess the effects of morbidity and mortality episodes on household income, medical spending, labour

  1. Work demands, job insecurity and sickness absence from work. how productive is the new, flexible labour force?

    Science.gov (United States)

    D'Souza, Rennie M; Strazdins, Lyndall; Broom, Dorothy H; Rodgers, Bryan; Berry, Helen L

    2006-06-01

    We investigate one aspect of productivity--sickness absence--and ask whether job insecurity and high work demands are associated with increased sickness absence and, if so, whether mental or physical health mediates this association. We further investigate if having control at work modifies these associations. We used cross-sectional survey data from 2,248 employees aged 40-44 years living in two cities of south-eastern Australia. Logistic regressions were used to compare the associations between job insecurity and demands among those with short (1-3 days) or long-term (> 3 days) sickness absence with those who had no sickness absence in the last four weeks. The mediating effects of mental and physical health were assessed by evaluating changes in the magnitude of the association between these work conditions and sickness absence. High job insecurity (OR = 3.28; 95% CI 1.54-6.95) and high work demands (OR = 1.62; 95% CI 1.13-2.30) were significantly associated with long-term, but not with short-term, sickness absence. These associations were unaffected by job control. Depression and anxiety explained 61% of the association between high work demands and long-term sickness absence and 30% of the association between job insecurity and long-term sickness absence. Difficult working conditions may reduce productivity by contributing to longer absences from work. Reforms intended to improve economic performance should address any potential health costs of insecurity or intensification, which could inadvertently decrease productivity, possibly through their impact on mental health.

  2. Employer, insurance, and health system response to long-term sick leave in the public sector: policy implications.

    Science.gov (United States)

    Heijbel, Bodil; Josephson, Malin; Jensen, Irene; Vingård, Eva

    2005-06-01

    This study has been conducted to describe the situation of long-term sick-listed persons employed in the public sector regarding the medical reasons of their sick leave, the duration of their problems, the duration of the actual sick leave, rehabilitation support, rehabilitation measures, and the persons expectations of the future. Response rate of a postal questionnaire, where 484 women and 51 men on long-term sick leave answered, was 69%. The study-group consisted of 90% women with a median age of 50 years. The most common reasons for sick listing were long-lasting musculoskeletal problems, especially neck/shoulder pain, low back pain and osteoarthritis or other joint problems and mental problems, especially depression and burn-out syndromes. Forty-seven procent of the men and 57% of the women had been on the sick list for more than a year. Only half of them had been subjected to the legally required rehabilitation investigation of the employer This half got access to rehabilitation programs and/or vocational rehabilitation to a greater extent than those who not had been subjected to rehabilitation investigation. Less than half had been in contact with the workplace-connected rehabilitation actors, the Occupational Health Service or the Trade Union. In spite of this the sick-listed persons had a positive view of their future return to work. For long-term sick-listed persons in the public sector, there is a great potential for improvements of the rehabilitation at the workplace arena, in the involvement and cooperation between the already existing rehabilitation actors, in order to promote return to work.

  3. Investigating source directivity for the 2012 Ml5.9 Emilia (Northern Italy) earthquake by jointly using High-rate GPS and Strong motion data

    Science.gov (United States)

    Avallone, A.; Herrero, A.; Latorre, D.; Rovelli, A.; D'Anastasio, E.

    2012-12-01

    On May, 20th 2012, the Ferrara and Modena provinces (Emilia Romagna, Northern Italy) were struck by a moderate magnitude earthquake (Ml 5.9). The focal mechanism is consistent with a ~E-W-striking thrust fault. The mainshock was recorded by 29 high-rate sampling (1-Hz) continuous GPS (HRGPS) stations belonging to scientific or commercial networks and by 55 strong motion (SM) stations belonging to INGV (Istituto Nazionale di Geofisica e Vulcanologia) and RAN (Rete Accelerometrica Nazionale) networks, respectively. The spatial distribution of both HRGPS and SM stations with respect to the mainshock location allows a satisfactory azimuthal coverage of the area. To investigate directivity effects during the mainshock occurrence, we analyze the spatial variation of the peak ground displacement (PGD) measured either for HRGPS or SM sites, using different methods. For each HRGPS and SM site, we rotated the horizontal time series to the azimuth direction and we estimated the GPS-related and the SM-related peak ground displacement (G-PGD and S-PGD, respectively) retrieved by transverse component. However, in contrast to GPS displacements, the double integration of the SM data can be affected by the presence of drifts and, thus, they have to be corrected by quasi-manual procedures. To more properly compare the G-PGDs to the S-PGDs, we used the response spectrum. A response spectrum is simply the response of a series of oscillators of varying natural frequency, that are forced into motion by the same input. The asymptotic value of the displacement response spectrum is the peak ground displacement. Thus, for each HRGPS and SM site, we computed the value of this asymptotic trend (G-PGDrs and S-PGDrs, respectively). This method allows simple automatic procedures. The consistency of the PGDs derived from HRGPS and SM is also evaluated for sites where the two instruments are collocated. The PGDs obtained by the two different methods and the two different data types suggest a

  4. Influenza in workplaces: transmission, workers' adherence to sick leave advice and European sick leave recommendations.

    Science.gov (United States)

    Edwards, Christina Hansen; Tomba, Gianpaolo Scalia; de Blasio, Birgitte Freiesleben

    2016-06-01

    Knowledge about influenza transmission in the workplace and whether staying home from work when experiencing influenza-like illness can reduce the spread of influenza is crucial for the design of efficient public health initiatives. This review synthesizes current literature on sickness presenteeism and influenza transmission in the workplace and provides an overview of sick leave recommendations in Europe for influenza. A search was performed on Medline, Embase, PsychINFO, Cinahl, Web of Science, Scopus and SweMed to identify studies related to workplace contacts, -transmission, -interventions and compliance with recommendations to take sick leave. A web-based survey on national recommendations and policies for sick leave during influenza was issued to 31 European countries. Twenty-two articles (9 surveys; 13 modelling articles) were eligible for this review. Results from social mixing studies suggest that 20-25% of weekly contacts are made in the workplace, while modelling studies suggest that on average 16% (range 9-33%) of influenza transmission occurs in the workplace. The effectiveness of interventions to reduce workplace presenteeism is largely unknown. Finally, estimates from studies reporting expected compliance with sick leave recommendations ranged from 71 to 95%. Overall, 18 countries participated in the survey of which nine (50%) had issued recommendations encouraging sick employees to stay at home during the 2009 A(H1N1) pandemic, while only one country had official recommendations for seasonal influenza. During the 2009 A(H1N1) pandemic, many European countries recommended ill employees to take sick leave. Further research is warranted to quantify the effect of reduced presenteeism during influenza illness. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association.

  5. Influenza in workplaces: transmission, workers’ adherence to sick leave advice and European sick leave recommendations

    Science.gov (United States)

    Tomba, Gianpaolo Scalia; de Blasio, Birgitte Freiesleben

    2016-01-01

    Background: Knowledge about influenza transmission in the workplace and whether staying home from work when experiencing influenza-like illness can reduce the spread of influenza is crucial for the design of efficient public health initiatives. Aim: This review synthesizes current literature on sickness presenteeism and influenza transmission in the workplace and provides an overview of sick leave recommendations in Europe for influenza. Methods: A search was performed on Medline, Embase, PsychINFO, Cinahl, Web of Science, Scopus and SweMed to identify studies related to workplace contacts, -transmission, -interventions and compliance with recommendations to take sick leave. A web-based survey on national recommendations and policies for sick leave during influenza was issued to 31 European countries. Results: Twenty-two articles (9 surveys; 13 modelling articles) were eligible for this review. Results from social mixing studies suggest that 20–25% of weekly contacts are made in the workplace, while modelling studies suggest that on average 16% (range 9–33%) of influenza transmission occurs in the workplace. The effectiveness of interventions to reduce workplace presenteeism is largely unknown. Finally, estimates from studies reporting expected compliance with sick leave recommendations ranged from 71 to 95%. Overall, 18 countries participated in the survey of which nine (50%) had issued recommendations encouraging sick employees to stay at home during the 2009 A(H1N1) pandemic, while only one country had official recommendations for seasonal influenza. Conclusions: During the 2009 A(H1N1) pandemic, many European countries recommended ill employees to take sick leave. Further research is warranted to quantify the effect of reduced presenteeism during influenza illness. PMID:27060594

  6. 19 CFR 210.26 - Other motions.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Other motions. 210.26 Section 210.26 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.26 Other motions. Motions pertaining to discovery shall be filed in...

  7. A ‘Balanced’ Life: Work-Life Balance and Sickness Absence in Four Nordic Countries

    Directory of Open Access Journals (Sweden)

    D Antai

    2015-10-01

    Full Text Available Background: Little attention has been given to the relationship between work-life balance and sickness absence. Objective: To investigate the association between poor work-life balance and sickness absence in 4 Nordic welfare states. Methods: Multivariable logistic regression analysis was performed on pooled cross-sectional data of workers aged 15–65 years from Denmark, Finland, Sweden, and Norway (n=4186 obtained from the 2010 European Working Conditions Survey (EWCS. Poor work-life balance was defined based on the fit between working hours and family or social commitments outside work. Self-reported sickness absence was measured as absence for ≥7 days from work for health reasons. Results: Poor work-life balance was associated with elevated odds (OR 1.38, 95% CI 1.06 to 1.80 of self-reported sickness absence and more health problems in the 4 Nordic countries, even after adjusting for several important confounding factors. Work-related characteristics, ie, no determination over schedule (OR 1.26, 95% CI 1.04 to 1.53, and job insecurity (OR 1.56, 95% CI 1.21 to 2.02 increased the likelihood of sickness absence, and household characteristics, ie, cohabitation status (OR 0.75, 95% CI 0.58 to 0.96 reduced this likelihood. The associations were non-significant when performed separately for women and men. Conclusion: Sickness absence is predicted by poor work-life balance. Findings suggest the need for implementation of measures that prevent employee difficulties in combining work and family life.

  8. A 'Balanced' Life: Work-Life Balance and Sickness Absence in Four Nordic Countries.

    Science.gov (United States)

    Antai, D; Oke, A; Braithwaite, P; Anthony, D S

    2015-10-01

    Little attention has been given to the relationship between work-life balance and sickness absence. To investigate the association between poor work-life balance and sickness absence in 4 Nordic welfare states. Multivariable logistic regression analysis was performed on pooled cross-sectional data of workers aged 15-65 years from Denmark, Finland, Sweden, and Norway (n=4186) obtained from the 2010 European Working Conditions Survey (EWCS). Poor work-life balance was defined based on the fit between working hours and family or social commitments outside work. Self-reported sickness absence was measured as absence for ≥7 days from work for health reasons. Poor work-life balance was associated with elevated odds (OR 1.38, 95% CI 1.06 to 1.80) of self-reported sickness absence and more health problems in the 4 Nordic countries, even after adjusting for several important confounding factors. Work-related characteristics, ie, no determination over schedule (OR 1.26, 95% CI 1.04 to 1.53), and job insecurity (OR 1.56, 95% CI 1.21 to 2.02) increased the likelihood of sickness absence, and household characteristics, ie, cohabitation status (OR 0.75, 95% CI 0.58 to 0.96) reduced this likelihood. The associations were non-significant when performed separately for women and men. Sickness absence is predicted by poor work-life balance. Findings suggest the need for implementation of measures that prevent employee difficulties in combining work and family life.

  9. Diagnosis of moderate acute radiation sickness

    International Nuclear Information System (INIS)

    Yu Shoucheng; Chen Zhijian; Chen Youxin

    1989-01-01

    Forty patients with malignant lymphoma were given 60 Co TLI. 21 cases received 6 Gy and 19 received 8 Gy. It was estimated that a single TLI of 6 and 8 Gy would correspond to TBI of 3.55 Gy and 4.25 Gy (average values) by analysing peripheral blood cell chromosome aberrations and 1.85-2.37 Gy by measuring red bone marrow stem cells clinically. Moderate acute radiation sickness with digestive tract reaction and hemopoietic and immunologic depression was observed. WBC and platelets decreased rapidly. Lymphocytes showed quantitative and qualitative changes even at early stage. All these indexes are significant for diagnosis. Besides, the degree of labial stimulation response, levels of C-reactive protein, corticoid, and urinal nucleoside and alkaloid base presented great changes both pre-and post-irradiation. Early diagnosis of moderate acute radiation sickness could be made in cancer patients subjected to 6-8 Gy TLI

  10. Sickness absence and sickness attendance--what people with neck or back pain think.

    Science.gov (United States)

    Hansson, Margareta; Boström, Carina; Harms-Ringdahl, Karin

    2006-05-01

    This study explores the decision of 33 men and women to be sick-listed from work for neck pain or low-back pain. Qualitative interviews with the subjects, who lived in a city or a sparsely populated area of Sweden, were tape-recorded, transcribed and analysed in the interpretive tradition by the three authors. New, intense and threatening pain quickly made persons report sick. For other pain, sickness absence, its timing and duration, were negotiated on the basis of the subjects' self-image, work-duty norms, organisational and extra-organisational work factors. Thirty-one people aimed to return to work, but spine-related pain was a hindrance. Five strategies to avoid, delay or shorten sickness absence were identified. Concepts of the illness flexibility model well described how the workers balanced the factors driving them from work and those forcing them or attracting them to remain. The conclusion is that reporting sick is neither undertaken lightly nor for short-term reasons only. Instead, personal history and anticipated future, spine-related pain, workplace and labour market factors are also important considerations.

  11. Prediction of sickness absenteeism, disability pension and sickness presenteeism among employees with back pain.

    Science.gov (United States)

    Bergström, Gunnar; Hagberg, Jan; Busch, Hillevi; Jensen, Irene; Björklund, Christina

    2014-06-01

    The primary aim of this study was to evaluate the predictive ability of the Örebro Musculoskeletal Pain Screening Questionnaire (ÖMPSQ) concerning long-term sick leave, sickness presenteeism and disability pension during a follow-up period of 2 years. The study group consisted of 195 employees visiting the occupational health service (OHS) due to back pain. Using receiver operating characteristic (ROC) curves, the area under the curve (AUC) varied from 0.67 to 0.93, which was from less accurate for sickness presenteeism to highly accurate for the prediction of disability pension. For registered sick leave during 6 months following the baseline the AUC from the ROC analyses was moderately accurate (0.81) and a cut off score of 90 rendered a high sensitivity of 0.89 but a low specificity of 0.46 whereas a cut off score of 105 improves the specificity substantially but at the cost of some sensitivity. The predictive ability appears to decrease with time. Several workplace factors beyond those included in the ÖMPSQ were considered but only social support at the workplace was significantly related to future long-term sick leave besides the total score of the ÖMPSQ. The results of this study extend and confirm the findings of earlier research on the ÖMPSQ. Assessment of psychosocial risk factors among employees seeking help for back pain at the OHS could be helpful in the prevention of work disabling problems.

  12. Dynamic Visual Acuity and Landing Sickness in Crewmembers Returning from Long-Duration Spaceflight

    Science.gov (United States)

    Rosenberg, M.J.F; Peters, B.T.; Reschke, M. F.

    2016-01-01

    Long-term exposure to microgravity causes sensorimotor adaptations that result in functional deficits upon returning to a gravitational environment. At landing the vestibular system and the central nervous system, responsible for coordinating head and eye movements, are adapted to microgravity and must re-adapt to the gravitational environment. This re-adaptation causes decrements in gaze control and dynamic visual acuity, with astronauts reporting oscillopsia and blurred vision. Dynamic visual acuity (DVA) is assessed using an oscillating chair developed in the Neuroscience Laboratory at JSC. This chair is lightweight and easily portable for quick deployment in the field. The base of the chair is spring-loaded and allows for manual oscillation of the subject. Using a metronome, the chair is vertically oscillated plus or minus 2 cm at 2 Hz by an operator, to simulate walking. While the subject is being oscillated, they are asked to discern the direction of Landolt-C optotypes of varying sizes and record their direction using a gamepad. The visual acuity thresholds are determined using an algorithm that alters the size of the optotype based on the previous response of the subject using a forced-choice best parameter estimation that is able to rapidly converge on the threshold value. Visual acuity thresholds were determined both for static (seated) and dynamic (oscillating) conditions. Dynamic visual acuity is defined as the difference between the dynamic and static conditions. Dynamic visual acuity measures will be taken prior to flight (typically L-180, L-90, and L-60) and up to eight times after landing, including up to 3 times on R plus 0. Follow up measurements will be taken at R plus 1 (approximately 36 hours after landing). Long-duration International Space Station crewmembers will be tested once at the refueling stop in Europe and once again upon return to Johnson Space Center. In addition to DVA, subjective ratings of motion sickness will be recorded

  13. The Negotiation of the Sick Role

    DEFF Research Database (Denmark)

    Mik-Meyer, Nanna; Roelsgaard Obling, Anne

    2012-01-01

    ’s particular circumstances in deciding whether that patient is legitimately sick. The doctor is thus a gatekeeper of legitimacy. This article presents results from a qualitative interview study conducted in Denmark with GPs concerning their approach to patients with MUS. We employ a symbolic interaction...... to which GPs are able to constitute these patients as people with social problems and problematic personality traits....

  14. Absenteeism due to sickness in coal miners

    Energy Technology Data Exchange (ETDEWEB)

    Szymczykiewicz, K.

    1980-01-01

    During two consecutive years sickness absence of 8005 miners from two pit coal mines (A and B) of different geological structure and mechanization degree was analysed. It was found that in mine ''A'' 37% had no sick leaves, whereas in mine ''B''--28%. Absence rate was similar in both mines (though the miners' work and living conditions differed), i.e. 5.21% in mine ''A'', and 5.98% in mine ''B''. Thus work and living conditions do not determine general sickness absence rate. The highest absence in both mines was that of miners frequently falling ill for a long time (approx. 5.5% miners). For the group the number of work disablement days was 28.8 and 26.7, respectively. Underground miners' sickness absence was higher than that of surface workers, the rate being 3.8 and 4.0 and 1.1 and 2.1, respectively. The highest absence was that of miners travelling to work on motor cycles (7.1 and 7.3) and bicycles (6.4 and 6.7). Those working regularly in the first shift were more frequently absent from work than those working in different shifts. Miners living in worse conditions had higher absence rate than those living in flats of a higher standard. Also elderly employees and those having children represented a higher absence rate. The highest absence rate was that of workers having four children, the lowest--that of single persons. In addition, specific absence rate of men, especially due to respiratory and circulatory system diseases, was found to be enhanced by smoking. Absence rate of smokers was 2--3 times higher than that of non-smokers.

  15. Sickness Absence: a Pan-European Study

    OpenAIRE

    Livanos, Ilias; Zangelidis, Alexandros

    2010-01-01

    This study, using the EU-LFS, examines the determinants of sickness absence in 26 EU countries. The analysis highlights the importance of demographic and workplace characteristics and of institutional and societal conditions. Female workers aged 26-35 exhibit higher absenteeism, possibly reflecting the level of high household labour pressure. Increased job insecurity, captured by temporary contracts, and labour market uncertainty, reflected in higher unemployment rates, have a negative effect...

  16. Work, Sickness, Absence, and Identity-Work

    OpenAIRE

    Trude Gjernes

    2013-01-01

    This article explores how a group of industrial workers experience long-term sickness absence and how they cope with this situation. The article presents data from in-depth interviews with male industrial workers employed in a Norwegian factory. The findings suggest that the factory workers handle their failing health by engaging in activities other than wage work. They did not accept a social situation characterized by passivity, social isolation, marginalization, or loss of self. The worker...

  17. Work-related physical and psychosocial risk factors for sick leave in patients with neck or upper extremity complaints.

    Science.gov (United States)

    Bot, Sandra D M; Terwee, Caroline B; van der Windt, Daniëlle A W M; van der Beek, Allard J; Bouter, Lex M; Dekker, Joost

    2007-08-01

    To study work-related physical and psychosocial risk factors for sick leave among patients who have visited their general practitioner for neck or upper extremity complaints. Three hundred and forty two patients with neck or upper extremity complaints completed self-report questionnaires at baseline and after 3 months. Cox regression models were used to investigate the association between work-related risk factors and sick leave (i.e., lost days from work due to neck or upper extremity complaints in 3 months). Effect modification by sick leave at baseline, sex, worrying and musculoskeletal co-morbidity was evaluated by adding product terms to the regression models. In the subgroup of patients who scored high on the pain copying scale "worrying" the hazard ratio of sick leave was 1.32 (95% CI 1.07-1.62) per 10% increase in heavy physical work. The subgroup of patients who were sitting for long periods of time had a reduced risk of sick leave as compared to patients who did not spend a lot of time sitting, again only in patients who scored high on the pain coping scale "worrying" (adjusted HR=0.17, 95%-CI 0.04-0.72). Other work-related risk factors were not significantly related to sick leave. Heavy physical work increased the risk of sick leave and prolonged sitting reduced the risk of sick leave in a subgroup of patients who worried much about their pain. Additional large longitudinal studies of sufficiently large size among employees with neck or upper extremity complaints are needed to confirm our results.

  18. Risk of sick leave and disability pension in working-age women and men with knee osteoarthritis.

    Science.gov (United States)

    Hubertsson, Jenny; Petersson, Ingemar F; Thorstensson, Carina A; Englund, Martin

    2013-03-01

    To investigate sick leave and disability pension in working-age subjects with knee osteoarthritis (OA) compared with the general population. Population-based cohort study: individual-level inpatient and outpatient Skåne Health Care Register data were linked with data from the Swedish Social Insurance Agency. In 2009 all working-age (16-64 years) Skåne County residents who in 1998-2009 had been diagnosed with knee OA (International Classification of Diseases-10 code M17) were identified and their sick leave and disability pension in 2009 related to those of the general working-age population (n=789 366) standardised for age. 15 345 working-age residents (49.6% women) with knee OA were identified. Compared with the general population, the RR (95% CI) of having had one or more episodes of sick leave during the year was 1.82 (1.73 to 1.91) for women and 2.03 (1.92 to 2.14) for men with knee OA. The corresponding risk for disability pension was 1.54 (1.48 to 1.60) for women and 1.36 (1.28 to 1.43) for men with knee OA. The annual mean number of sick days was 87 for each patient with knee OA and 57 for the general population (age- and sex-standardised). Of all sick leave and disability pension in the entire population, 2.1% of days were attributable to knee OA or associated comorbidity in the patients with knee OA (3.1% for sick leave and 1.8% for disability pension). Subjects with doctor-diagnosed knee OA have an almost twofold increased risk of sick leave and about 40-50% increased risk of disability pension compared with the general population. About 2% of all sick days in society are attributable to knee OA.

  19. Sick at work: prevalence and determinants among healthcare workers, western Ethiopia: an institution based cross-sectional study.

    Science.gov (United States)

    Mekonnen, Tesfaye Hambisa; Tefera, Mekuriaw Alemayewu; Melsew, Yayehirad Alemu

    2018-01-01

    Going to work despite feeling sick also known as sickness presenteeism is one of the emerging global occupational health challenges. Sickness presenteeism negatively affects both health of work forces and productivity of organizations in general. However, there is insufficient research exploring this situation in majority of the Sub-Saharan African countries, including Ethiopia. Thus this study intended to investigate the prevalence and determinant factors of sickness presenteeism among health care workers, Western Ethiopia. This study used an institution based cross-sectional quantitative study design. The study period was from February to March, 2017. We employed simple random sampling method to select 360 study samples. Data collection was performed by pre-tested structured and self- administered questionnaire. We used SPSS version 20 to carry out binary logistic regression analysis. Odds ratio with 95% confidence intervals was calculated and significance of associations was determined at p -value Educational status [AOR:2.1, 95%CI: (1.17,3.90)], financial problem [AOR:1.9,95%CI:(1.07,3.46)], sickness absenteeism [AOR:2.7,95% CI:(1.50,5.02)], lack of staff replacement [AOR:2.7,95%CI:(1.50,5.02)], absence of occupational health services [AOR:3.0,95%CI:(1.34,6.70)], and pressure from supervisor [AOR:1.8,95% CI:(1.01,3.31)] were significant predictors of the dependent variable. Relatively higher proportions of workers indicated sickness presenteeism as compared to other studies. Risk factors like educational status, personal financial problem, sickness absenteeism, lack of staff replacement, absence of occupational health services, and pressure from supervisors considerably increased the likely occurrence of employees' sick attendance. It is advisable for health care managers to hire adequate health care staffs, to implement basic occupational health services and to design strategies which reduce pressure from supervisors.

  20. Interactional justice at work is related to sickness absence: a study using repeated measures in the Swedish working population.

    Science.gov (United States)

    Leineweber, Constanze; Bernhard-Oettel, Claudia; Peristera, Paraskevi; Eib, Constanze; Nyberg, Anna; Westerlund, Hugo

    2017-12-08

    Research has shown that perceived unfairness contributes to higher rates of sickness absence. While shorter, but more frequent periods of sickness absence might be a possibility for the individual to get relief from high strain, long-term sickness absence might be a sign of more serious health problems. The Uncertainty Management Model suggests that justice is particularly important in times of uncertainty, e.g. perceived job insecurity. The present study investigated the association between interpersonal and informational justice at work with long and frequent sickness absence respectively, under conditions of job insecurity. Data were derived from the 2010, 2012, and 2014 biennial waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH). The final analytic sample consisted of 19,493 individuals. We applied repeated measures regression analyses through generalized estimating equations (GEE), a method for longitudinal data that simultaneously analyses variables at different time points. We calculated risk of long and frequent sickness absence, respectively in relation to interpersonal and informational justice taking perceptions of job insecurity into account. We found informational and interpersonal justice to be associated with risk of long and frequent sickness absence independently of job insecurity and demographic variables. Results from autoregressive GEE provided some support for a causal relationship between justice perceptions and sickness absence. Contrary to expectations, we found no interaction between justice and job insecurity. Our results underline the need for fair and just treatment of employees irrespective of perceived job insecurity in order to keep the workforce healthy and to minimize lost work days due to sickness absence.

  1. The role of lifestyle, health, and work in educational inequalities in sick leave and productivity loss at work.

    Science.gov (United States)

    Robroek, Suzan J W; van Lenthe, Frank J; Burdorf, Alex

    2013-08-01

    To investigate the influence of lifestyle, health, and work conditions in the association between education and productivity loss at work and sick leave. Employees of six companies filled out a questionnaire on demographics, lifestyle-related, health, and work-related factors, and productivity loss at work and sick leave at baseline (n = 915) and after 1-year (n = 647). Employees with a low education were more likely to report productivity loss at work (OR = 1.49, 95 % CI 0.98-2.26) and sick leave (OR = 1.81, 95 % CI 1.15-2.85). After adjustment for lifestyle, health, and work conditions, the association between education and productivity loss at work did not attenuate. Work conditions attenuated the association between low education and sick leave (OR = 1.62, 95 % CI 1.01-2.61), and additional adjustment for health and lifestyle-related factors further reduced the strength of the association (OR = 1.42, 95 % CI 0.86-2.34). Work conditions and lifestyle-related factors partly explained the association between education and sick leave, but did not influence the association between education and productivity loss at work. The educational differences in sick leave prompt for interventions that address behavioral aspects as well as work-related and lifestyle-related factors.

  2. Changes in sick leave among Swedish dental patients after treatment for dental fear.

    Science.gov (United States)

    Hakeberg, M; Berggren, U

    1993-03-01

    The most obvious consequence of a genuine dental phobic reaction is the avoidance of necessary dental care. Previous research has indicated that such avoidance results in deterioration of the oral status, which subsequently worsens patients' well-being and quality of life. The authors' previous investigations have shown overt behavioural and social effects by an increased time spent on sick leave compared with the public experience. Self-reports by patients also indicated that the time spent on sick leave was reduced after successful treatment for dental fear. The present investigation assessed the frequency of sick leave days among patients with dental fear and avoidance with regard to successful or unsuccessful treatment for dental fear (subsequent regular dental visit habits). A sub-sample of the fear group was compared with a group of matched controls. Data were collected from the official register of the National Health Insurance Board. It was revealed that the number of sick leave days was significantly reduced after treatment for dental fear among treated patients. This effect was also confirmed by a significant post-treatment difference between treated patients and those who discontinued or never started treatment. When compared with a matched control group, the positive change was further supported by a significant pre-treatment difference and a non-significant post-treatment difference.

  3. GPs' negotiation strategies regarding sick leave for subjective health complaints

    DEFF Research Database (Denmark)

    Nilsen, Stein Tore; Malterud, Kirsti; Werner, Erik L.

    2015-01-01

    Objectives: To explore general practitioners ’(GPs’) specific negotiation strategies regarding sick-leave issues with patientssuffering from subjective health complaints. Design: Focus-group study. Setting: Nine focus-group interviews in three citiesin different regions of Norway. Participants: 48...... GPs (31 men, 17 women; age 32–65), participating in a course dealing with diagnostic practice and assessment of sickness certifi cates related to patients with subjective health complaints. Results: TheGPs identified some specific strategies that they claimed to apply when dealing with the question...... to sick leave. Conclusions and implications: GPs seem to have a conscious approach to negotiations of sickness certification, as they report applying specific strategies to limit the duration of sick leave due to subjective health complaints. This give-and-take way of handling sick leave negotiations has...

  4. Screening manual and office workers for risk of long-term sickness absence: cut-off points for the Work Ability Index

    NARCIS (Netherlands)

    Schouten, L.S.; Joling, C.I.; van der Gulden, J.W.J.; Heymans, M.W.; Bultmann, U.; Roelen, C.A.M.

    2015-01-01

    OBJECTIVES: The aim of this study was to investigate the Work Ability Index (WAI) as a tool to screen for risk of different durations of long-term sickness absence (LTSA) among manual and office workers.

  5. The contribution of work engagement to self-perceived health, work ability, and sickness absence beyond health behaviors and work-related factors

    NARCIS (Netherlands)

    Rongen, Anne; Robroek, Suzan J W; Schaufeli, Wilmar|info:eu-repo/dai/nl/073779563; Burdorf, Alex

    2014-01-01

    Objective: To investigate whether work engagement influences self-perceived health, work ability, and sickness absence beyond health behaviors and work-related characteristics. Methods: Employees of two organizations participated in a 6-month longitudinal study (n = 733). Using questionnaires,

  6. Some problems of antibiotic therapy in radiation sickness

    International Nuclear Information System (INIS)

    Shalnova, G.A.

    1975-01-01

    Data on the application of antibiotics and the mechanism of their action in radiation sickness are reviewed. Questions are discussed, such as the effect of antibiotics on the course and outcome of radiation sickness, the development of dysbacteriosis following irradiation, the effect of antibiotics on endogenic infection, the development of resistance of autoflora microbes to antibiotics in an irradiated organism and various aspects of the mechanism of action of antibiotics in radiation sickness. (author)

  7. The indirect association of job strain with long-term sickness absence through bullying: a mediation analysis using structural equation modeling

    Directory of Open Access Journals (Sweden)

    Heidi Janssens

    2016-08-01

    Full Text Available Abstract Background In this longitudinal study the complex interplay between both job strain and bullying in relation to sickness absence was investigated. Following the “work environment hypothesis”, which establishes several work characteristics as antecedents of bullying, we assumed that job strain, conceptualized by the Job-Demand-Control model, has an indirect relation with long-term sickness absence through bullying. Methods The sample consisted of 2983 Belgian workers, aged 30 to 55 years, who participated in the Belstress III study. They completed a survey, including the Job Content Questionnaire and a bullying inventory, at baseline. Their sickness absence figures were registered during 1 year follow-up. Long-term sickness absence was defined as at least 15 consecutive days. A mediation analysis, using structural equation modeling, was performed to examine the indirect association of job strain through bullying with long-term sickness absence. The full structural model was adjusted for several possible confounders: age, gender, occupational group, educational level, company, smoking habits, alcohol use, body mass index, self-rated health, baseline long-term sickness absence and neuroticism. Results The results support the hypothesis: a significant indirect association of job strain with long-term sickness absence through bullying was observed, suggesting that bullying is an intermediate variable between job strain and long-term sickness absence. No evidence for the reversed pathway of an indirect association of bullying through job strain was found. Conclusions Bullying was observed as a mediating variable in the relation between job strain and sickness absence. The results suggest that exposure to job strain may create circumstances in which a worker risks to become a target of bullying. Our findings are generally in line with the work environment hypothesis, which emphasizes the importance of organizational work factors in the

  8. Sick-leave track record and other potential predictors of a disability pension. A population based study of 8,218 men and women followed for 16 years

    Directory of Open Access Journals (Sweden)

    Rosengren Annika

    2009-04-01

    Full Text Available Abstract Background A number of previous studies have investigated various predictors for being granted a disability pension. The aim of this study was to test the efficacy of sick-leave track record as a predictor of being granted a disability pension in a large dataset based on subjects sampled from the general population and followed for a long time. Methods Data from five ongoing population-based Swedish studies was used, supplemented with data on all compensated sick leave periods, disability pensions granted, and vital status, obtained from official registers. The data set included 8,218 men and women followed for 16 years, generated 109,369 person years of observation and 97,160 sickness spells. Various measures of days of sick leave during follow up were used as independent variables and disability pension grant was used as outcome. Results There was a strong relationship between individual sickness spell duration and annual cumulative days of sick leave on the one hand and being granted a disability pension on the other, among both men and women, after adjustment for the effects of marital status, education, household size, smoking habits, geographical area and calendar time period, a proxy for position in the business cycle. The interval between sickness spells showed a corresponding inverse relationship. Of all the variables studied, the number of days of sick leave per year was the most powerful predictor of a disability pension. For both men and women 245 annual sick leave days were needed to reach a 50% probability of transition to disability. The independent variables, taken together, explained 96% of the variation in disability pension grantings. Conclusion The sick-leave track record was the most important predictor of the probability of being granted a disability pension in this study, even when the influences of other variables affecting the outcome were taken into account.

  9. The indirect association of job strain with long-term sickness absence through bullying: a mediation analysis using structural equation modeling.

    Science.gov (United States)

    Janssens, Heidi; Braeckman, Lutgart; De Clercq, Bart; Casini, Annalisa; De Bacquer, Dirk; Kittel, France; Clays, Els

    2016-08-22

    In this longitudinal study the complex interplay between both job strain and bullying in relation to sickness absence was investigated. Following the "work environment hypothesis", which establishes several work characteristics as antecedents of bullying, we assumed that job strain, conceptualized by the Job-Demand-Control model, has an indirect relation with long-term sickness absence through bullying. The sample consisted of 2983 Belgian workers, aged 30 to 55 years, who participated in the Belstress III study. They completed a survey, including the Job Content Questionnaire and a bullying inventory, at baseline. Their sickness absence figures were registered during 1 year follow-up. Long-term sickness absence was defined as at least 15 consecutive days. A mediation analysis, using structural equation modeling, was performed to examine the indirect association of job strain through bullying with long-term sickness absence. The full structural model was adjusted for several possible confounders: age, gender, occupational group, educational level, company, smoking habits, alcohol use, body mass index, self-rated health, baseline long-term sickness absence and neuroticism. The results support the hypothesis: a significant indirect association of job strain with long-term sickness absence through bullying was observed, suggesting that bullying is an intermediate variable between job strain and long-term sickness absence. No evidence for the reversed pathway of an indirect association of bullying through job strain was found. Bullying was observed as a mediating variable in the relation between job strain and sickness absence. The results suggest that exposure to job strain may create circumstances in which a worker risks to become a target of bullying. Our findings are generally in line with the work environment hypothesis, which emphasizes the importance of organizational work factors in the origin of bullying. This study highlights that remodeling jobs to reduce

  10. Sick building syndrome: A disease of modern age

    Directory of Open Access Journals (Sweden)

    Nikić Dragana

    2004-01-01

    Full Text Available Sick building syndrome (SBS is a term used to describe situation in building when more than 30% of occupants suffer from various symptoms which tend to increase by severity during the time people spend in "sick" building and disappear when they leave the building. Typical cases of SBS report vague symptoms, which cannot be objectively measured, and sufferers usually show no clinical signs of illness. Symptom heterogeneity suggests that they do not represent a single disorder. The objective of our study was to establish if SBS is present in our town because new buildings have been built lately producing the artificial environment - exclusively artificial lightning and mechanical ventilation. A total of 812 subjects were included in our study. The investigation of SBS was performed by standardized questionnaires to determine the prevalence of symptoms and complaints. Questionnaires were used to collect data on perception of environment conditions and health during the period they work in this building. The subjects were divided in three groups according to sex, level of education and ownership. Our data suggested that the incidence of symptoms was higher in employers than in owners of the offices. Moreover, the prevalence of SBS was very high - up to 74.76%. It is obvious that certain physical, psychological and organizational factors are involved in the incidence of symptoms, but our investigation suggests that physical factor has a dominant role in development of symptoms, particularly low humidity and low air flow. In addition, our judgment is that SBS exists in our city, probably in the whole country and, therefore, it must be investigated properly.

  11. Within-Case and Cross-Case Analyses of Questions Posed by Fifth-Grade Students Working in Small Groups to Investigate Pendulum Motion

    Science.gov (United States)

    Tisel, James Michael

    The focus of this basic qualitative research is student questions in an unstructured inquiry setting. Case and cross-case analyses were conducted (Miles and Huberman, 1984) of the questions posed by fifth grade students working in laboratory groups of size three to five students as they investigated pendulum motion. To establish the conceptual framework for the study, literature was reviewed in the areas of cognitive theory (constructivism, conceptual change, and other theories), approaches to science, and the importance of student questions in the learning process. A review of group work, related studies of student questions and activities and relevant methods of qualitative research was also undertaken. The current study occupies the relatively unique position of being about the questions students posed to each other (not the teacher) at the outset of and throughout an unstructured inquiry activity with a minimum of teacher initiation or intervention. The focus is on finding out what questions students ask, when they ask them, what categories the questions fall into in relation to possible models of the scientific method, student motivation, and what role the questions play as the students take part in an inquiry activity. Students were video and/or audio-recorded as they did the investigation. They wrote down their questions during one-minute pauses that occurred at roughly eight-minute intervals. The groups were interviewed the next day about their experience. The recordings, question sheets, and interview accounts and recordings were analyzed by the researcher. Accounts of the experience of each group were prepared, and reiterated attempts were made to classify the questions as the main themes and categories emerged. It was found that students posed their key research question (most typically related to pendulum damping effects) midway through the first half of their activity, after having first met some competence and other needs in relation to measurement

  12. Occupational exposures and sick leave during pregnancy: results from a Danish cohort study.

    Science.gov (United States)

    Hansen, Mette Lausten; Thulstrup, Ane Marie; Juhl, Mette; Kristensen, Jette Kolding; Ramlau-Hansen, Cecilia Høst

    2015-07-01

    This study aimed to investigate associations between work postures, lifting at work, shift work, work hours, and job strain and the risk of sick leave during pregnancy from 10-29 completed pregnancy weeks in a large cohort of Danish pregnant women. Data from 51 874 pregnancies in the Danish National Birth Cohort collected between 1996-2002 were linked to the Danish Register for Evaluation of Marginalization. Exposure information was based on telephone interviews. Hazard ratios (HR) with 95% confidence intervals (95% CI) were calculated by Cox regression analysis, using time of first episode of sick leave as the primary outcome. We found statistically significant associations between all the predictors and risk of sick leave; for non-sitting work postures (HRrange 1.55-2.79), cumulative lifting HRtrend 1.29, 95% CI 1.26-1.31, shift work (HRevening 1.90, 95% CI 1.73-2.09, HRnight 1.52, 95% CI 1.15-2.01), monthly night shifts HRtrend 1.12, 95% CI 1.11-1.14, increasing weekly work hours HRtrend 0.93, 95% CI 0.91-0.95 and high job strain HR 1.52, 95% CI 1.42-1.63. Some exposures influenced HR in either a positive or negative time-dependent way. Our results support previous findings and suggest that initiatives to prevent sick leave during pregnancy could be based on work conditions. Preventive measures may have important implications for pregnant women and workplaces.

  13. Sick Leave and Factors Influencing Sick Leave in Adult Patients with Atopic Dermatitis: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Harmieke van Os-Medendorp

    2015-03-01

    Full Text Available Background: Little is known about the prevalence of sick leave due to atopic dermatitis (AD. The current literature on factors influencing sick leave is mostly derived from other chronic inflammatory diseases. This study aimed to determine the prevalence of sick leave due to AD and to identify influencing factors. Methods: A cross-sectional study was carried out in adult patients with AD. Outcome measures: sick leave during the two-week and one-year periods, socio-demographic characteristics, disease severity, quality of life and socio-occupational factors. Logistic regression analyses were used to determine influencing factors on sick leave over the two-week period. Results: In total, 253 patients were included; 12% of the patients had to take sick leave in the last two weeks due to AD and 42% in the past year. A higher level of symptom interference (OR 1.26; 95% CI 1.13–1.40 or perfectionism/diligence (OR 0.90; 95% CI 0.83–0.96 may respectively increase or decrease the number of sick leave days. Conclusion: Sick leave in patients with AD is a common problem and symptom interference and perfectionism/diligence appeared to influence it. Novel approaches are needed to deal with symptoms at work or school to reduce the amount of sick leave due to AD.

  14. Sick Leave and Factors Influencing Sick Leave in Adult Patients with Atopic Dermatitis: A Cross-Sectional Study.

    Science.gov (United States)

    van Os-Medendorp, Harmieke; Appelman-Noordermeer, Simone; Bruijnzeel-Koomen, Carla; de Bruin-Weller, Marjolein

    2015-03-27

    Little is known about the prevalence of sick leave due to atopic dermatitis (AD). The current literature on factors influencing sick leave is mostly derived from other chronic inflammatory diseases. This study aimed to determine the prevalence of sick leave due to AD and to identify influencing factors. A cross-sectional study was carried out in adult patients with AD. sick leave during the two-week and one-year periods, socio-demographic characteristics, disease severity, quality of life and socio-occupational factors. Logistic regression analyses were used to determine influencing factors on sick leave over the two-week period. In total, 253 patients were included; 12% of the patients had to take sick leave in the last two weeks due to AD and 42% in the past year. A higher level of symptom interference (OR 1.26; 95% CI 1.13-1.40) or perfectionism/diligence (OR 0.90; 95% CI 0.83-0.96) may respectively increase or decrease the number of sick leave days. Sick leave in patients with AD is a common problem and symptom interference and perfectionism/diligence appeared to influence it. Novel approaches are needed to deal with symptoms at work or school to reduce the amount of sick leave due to AD.

  15. Positive and negative consequences of sick leave for the individual, with special focus on part-time sick leave.

    Science.gov (United States)

    Sieurin, Leif; Josephson, Malin; Vingård, Eva

    2009-01-01

    To describe the consequences of long-term sick leave (>28 days) on working situation, health and lifestyle among employees from the public sector in Sweden. Employees in four county councils and two municipalities on long term sick leave on 1 November 2005 (n = 1,128) answered a questionnaire in February 2006. The response rate was 71.7%. Eighty seven per cent were still on sick leave when the questionnaire was answered: 54% part time and 33% full time. Reporting positive consequences was rare but reporting negative consequences, such as effects on the development of salary, the possibilities of pursuing a career or to change to another job were common. Sick leave seemed to lead to a considerable loss of zest for work, even if the respondents were back in work full time. Regardless of the negative consequences at work, 92% of those on part-time sick leave believed that the part-time sick leave was good for them even if many thought it had negative consequences for employer and colleagues. Long-term sick leave has negative consequences for the individual in work situations, even for those back at work full time. The development of salary and career seem to be most affected. The attitude towards part-time sick leave was positive and this result indicates that there is a potential for an increased degree of partial return to work in the group of people on long-term sick leave.

  16. Spinal decompression sickness: mechanical studies and a model.

    Science.gov (United States)

    Hills, B A; James, P B

    1982-09-01

    Six experimental investigations of various mechanical aspects of the spinal cord are described relevant to its injury by gas deposited from solution by decompression. These show appreciable resistances to gas pockets dissipating by tracking along tissue boundaries or distending tissue, the back pressure often exceeding the probable blood perfusion pressure--particularly in the watershed zones. This leads to a simple mechanical model of spinal decompression sickness based on the vascular "waterfall" that is consistent with the pathology, the major quantitative aspects, and the symptomatology--especially the reversibility with recompression that is so difficult to explain by an embolic mechanism. The hypothesis is that autochthonous gas separating from solution in the spinal cord can reach sufficient local pressure to exceed the perfusion pressure and thus occlude blood flow.

  17. Identifying the Subtle Presentation of Decompression Sickness.

    Science.gov (United States)

    Alea, Kenneth

    2015-12-01

    Decompression sickness is an inherent occupational hazard that has the possibility to leave its victims with significant long-lasting effects that can potentially impact an aircrew's flight status. The relative infrequency of this hazard within the military flying community along with the potentially subtle presentation of decompression sickness (DCS) has the potential to result in delayed diagnosis and treatment, leading to residual deficits that can impact a patient's daily life or even lead to death. The patient presented in this work was diagnosed with a Type II DCS 21 h after a cabin decompression at 35,000 ft (10,668 m). The patient had been asymptomatic with a completely normal physical/neurological exam following his flight. The following day, he presented with excessive fatigue and on re-evaluation was recommended for hyperbaric therapy, during which his symptoms completely resolved. He was re-evaluated 14 d later and cleared to resume flight duties without further incident. The manifestation of this patient's decompression sickness was subtle and followed an evaluation that failed to identify any focal findings. A high index of suspicion with strict follow-up contributed to the identification of DCS in this case, resulting in definitive treatment and resolution of the patient's symptoms. Determination of the need for hyperbaric therapy following oxygen supplementation and a thorough history and physical is imperative. If the diagnosis is in question, consider preemptive hyperbaric therapy as the benefits of treatment in DCS outweigh the risks of treatment. Finally, this work introduces the future potential of neuropsychological testing for both the diagnosis of DCS as well as assessing the effectiveness of hyperbaric therapy in Type II DCS.

  18. Changes in alcohol drinking and subsequent sickness absence.

    Science.gov (United States)

    Salonsalmi, Aino; Rahkonen, Ossi; Lahelma, Eero; Laaksonen, Mikko

    2015-06-01

    The aim was to examine whether changes in alcohol drinking are associated with sickness absence. Repeated postal questionnaires on alcohol drinking were conducted among employees of the City of Helsinki in 2000-2 and 2007 to assess changes in drinking habits between these two time points. Data on the number of self-certified and medically confirmed sickness absences were derived from the employer's register. Sickness absences were followed from 2007 until the end of 2010 among employees participating in both questionnaire surveys. The study includes 3252 female and 682 male employees 40-60 years old at baseline. Poisson regression was used in the data analysis and population attributable fractions (PAFs) were calculated. Alcohol drinking was associated especially with self-certified sickness absence. Rate ratios (RRs) and 95% confidence intervals (CIs) for increasing weekly average drinking were 1.38, 1.18-1.62 among women and 1.58, 1.18-2.12 among men. Also stable problem drinking (for women 1.39, 1.26-1.54, for men 1.44, 1.10-1.87) and among women stable heavy drinking (1.53, 1.20-1.94) increased self-certified sickness absence. There were associations between alcohol drinking and medically confirmed sickness absence but these were mainly explained by health and health behaviours. Also, a decrease in weekly average drinking was associated with sickness absence among women whereas among men former problem drinking increased sickness absence. According to the PAF values, problem drinking had a stronger contribution to sickness absence than weekly average drinking. Alcohol drinking is particularly associated with self-certified sickness absence. Reducing adverse drinking habits is likely to prevent sickness absence. © 2015 the Nordic Societies of Public Health.

  19. Sick-visit immunizations and delayed well-baby visits.

    Science.gov (United States)

    Robison, Steve G

    2013-07-01

    Giving recommended immunizations during sick visits for minor and acute illness such as acute otitis media has long been an American Academy of Pediatrics/Advisory Committee on Immunization Practice recommendation. An addition to the American Academy of Pediatrics policy in 2010 advised considering whether giving immunizations at the sick visit would discourage making up missed well-baby visits. This study quantifies the potential tradeoff between sick-visit immunizations and well-baby visits. This study was a retrospective cohort analysis with a case-control component of sick visits for acute otitis media that supplanted normal well-baby visits at age 2, 4, or 6 months. Infants were stratified for sick-visit immunization, no sick-visit immunization but quick makeup well-baby visits, or no sick-visit immunizations or quick makeup visits. Immunization rates and well-baby visit rates were assessed through 24 months of age. For 1060 study cases, no significant difference was detected in immunization rates or well-baby visits through 24 months of age between those with or without sick-visit immunizations. Thirty-nine percent of infants without a sick-visit shot failed to return for a quick makeup well-baby visit; this delayed group was significantly less likely to be up-to-date for immunizations (relative risk: 0.66) and had fewer well-baby visits (mean: 3.8) from 2 through 24 months of age compared with those with sick-visit shots (mean: 4.7). The substantial risk that infants will not return for a timely makeup well-baby visit after a sick visit should be included in any consideration of whether to delay immunizations.

  20. Smartphone-Enabled Heart Rate Variability and Acute Mountain Sickness.

    Science.gov (United States)

    Mellor, Adrian; Bakker-Dyos, Josh; OʼHara, John; Woods, David Richard; Holdsworth, David A; Boos, Christopher J

    2018-01-01

    The autonomic system and sympathetic activation appears integral in the pathogenesis of acute mountain sickness (AMS) at high altitude (HA), yet a link between heart rate variability (HRV) and AMS has not been convincingly shown. In this study we investigated the utility of the smartphone-derived HRV score to predict and diagnose AMS at HA. Twenty-one healthy adults were investigated at baseline at 1400 m and over 10 days during a trek to 5140 m. HRV was recorded using the ithlete HRV device. Acute mountain sickness occurred in 11 subjects (52.4%) at >2650 m. HRV inversely correlated with AMS Scores (r = -0.26; 95% CI, -0.38 to -0.13: P HRV significantly fell at 3700, 4100, and 5140 m versus low altitude. HRV scores were lower in those with both mild (69.7 ± 14.0) and severe AMS (67.1 ± 13.1) versus those without AMS (77.5 ± 13.1; effect size n = 0.043: P = 0.007). The HRV score was weakly predictive of severe AMS (AUC 0.74; 95% CI, 0.58-0.89: P = 0.006). The change (delta) in the HRV Score (compared with baseline at 1400 m) was a moderate diagnostic marker of severe AMS (AUC 0.80; 95% CI, 0.70-0.90; P = 0.0004). A fall in the HRV score of >5 had a sensitivity of 83% and specificity of 60% to identify severe AMS (likelihood ratio 1.9). Baseline HRV at 1400 m was not predictive of either AMS at higher altitudes. The ithlete HRV score can be used to help in the identification of severe AMS; however, a baseline score is not predictive of future AMS development at HA.

  1. Shift work and mental health sickness absence : A 10-year observational cohort study among male production workers

    NARCIS (Netherlands)

    Norder, Giny; Roelen, Corne A. M.; Bultmann, Ute; van der Klink, Jac J. L.

    Objectives Epidemiological studies investigating mental-health-related sickness absence (SA) among shift workers are lacking. This 10-year observational study investigated the risk of mental health SA among shift compared with day workers. Methods The data of 5826 male production workers were used

  2. Systematic review of active workplace interventions to reduce sickness absence.

    Science.gov (United States)

    Odeen, M; Magnussen, L H; Maeland, S; Larun, L; Eriksen, H R; Tveito, T H

    2013-01-01

    The workplace is used as a setting for interventions to prevent and reduce sickness absence, regardless of the specific medical conditions and diagnoses. To give an overview of the general effectiveness of active workplace interventions aimed at preventing and reducing sickness absence. We systematically searched PubMed, Embase, Psych-info, and ISI web of knowledge on 27 December 2011. Inclusion criteria were (i) participants over 18 years old with an active role in the intervention, (ii) intervention done partly or fully at the workplace or at the initiative of the workplace and (iii) sickness absence reported. Two reviewers independently screened articles, extracted data and assessed risk of bias. A narrative synthesis was used. We identified 2036 articles of which, 93 were assessed in full text. Seventeen articles were included (2 with low and 15 with medium risk of bias), with a total of 24 comparisons. Five interventions from four articles significantly reduced sickness absence. We found moderate evidence that graded activity reduced sickness absence and limited evidence that the Sheerbrooke model (a comprehensive multidisciplinary intervention) and cognitive behavioural therapy (CBT) reduced sickness absence. There was moderate evidence that workplace education and physical exercise did not reduce sickness absence. For other interventions, the evidence was insufficient to draw conclusions. The review found limited evidence that active workplace interventions were not generally effective in reducing sickness absence, but there was moderate evidence of effect for graded activity and limited evidence for the effectiveness of the Sheerbrooke model and CBT.

  3. Sick leave analysis among self-employed Dutch farmers

    NARCIS (Netherlands)

    Hartman, E.; Oude Vrielink, H.H.E.; Huirne, R.B.M.; Metz, J.H.M.

    2003-01-01

    Background Agriculture is one of the most physically demanding and risky industries. Aim The objective of this study was to provide baseline data on the diagnoses, occurrence and duration of sick leave of self-employed Dutch farmers. Method A database of 22807 sick leave claims of 12627 farmers

  4. Identifying employees at risk for job loss during sick leave

    NARCIS (Netherlands)

    Flach, Peter A.; Groothoff, Johan W.; Bultmann, Ute

    2013-01-01

    Purpose: To examine the associations between medical, work-related, organizational and sociodemographic factors and job loss during sick leave in a Dutch population of 4132 employees on sick leave. Methods: Data were assessed by occupational health physicians (OHPs) on sociodemographic, medical,

  5. SICK SINUS SYNDROME IN PATIENTS WITH ACUTE CEREBROVASCULAR ACCIDENTS

    Directory of Open Access Journals (Sweden)

    E. K. Kazakova

    2015-01-01

    Full Text Available The article presents a clinical case of 2 patients with heart arrhythmias of the sick sinus syndrome type, who were implanted electriccardiac pacemakers in the acute period of cerebrovascular accidents. There were no cardiac complaints in the clinical manifestation, however, a comprehensive assessment confirmed the diagnosis of sick sinus syndrome.

  6. Does muscle strength predict future musculoskeletal disorders and sickness absence?

    DEFF Research Database (Denmark)

    Faber, A; Sell, L; Hansen, J V

    2012-01-01

    High muscle strength is considered relevant for preventing musculoskeletal disorders and long-term sickness absence. However, prospective studies on the association between muscle strength and future musculoskeletal disorders and long-term sickness absence are few and show contrasting results....

  7. Sickness Behaviour: Causes and Effects | Viljoen | South African ...

    African Journals Online (AJOL)

    This paper discusses sickness behaviour as a central motivational state. It deals with the adaptational value and underlying mechanisms of sickness behaviour and with the consequences of the body's failure to terminate the activity of the symptoms-producing cytokines. SA Fam Pract 2003;45(10):15-18 ...

  8. Identifying workers at risk of sickness absence by questionnaire

    NARCIS (Netherlands)

    Roelen, Corne A. M.; van der Pol, Tjepke R.; Koopmans, Petra C.; Groothoff, Johan W.

    2006-01-01

    Background Sickness absence is an important economic problem, because of high costs and lost productivity. Determining factors associated with increased risk of sickness absence may lead to the development of preventive measures. Aims To determine whether self-report questionnaires can identify

  9. Current problems of prevention diagnosis and treatment of radiation sickness

    International Nuclear Information System (INIS)

    Gus'kova, A.K.

    1986-01-01

    Causes of increasing interest to the problems of prevention, diagnosis and treatment of radiation sickness are presented. On the basis of recent publications some new aspects as quantitative criteria in radiobiology, organization problems of medical aid at radiation incidents estimation of efficiency of preventive medicine and radiation sickness therapy, theoretical development of radiotherapy of different organs et al., are characterized

  10. Subjective health complaints in relation to sickness absence

    NARCIS (Netherlands)

    Roelen, Corne A. M.; Koopmans, Petra C.; Groothoff, Johan W.

    2010-01-01

    Objective: The Dutch population is healthy in terms of living and working conditions, but the levels of subjective health complaints (SHC) and sickness absence are high in the Dutch workforce. Are SHC related to sickness absence? Participants: The study population included the personnel of four

  11. Sick leave among people in paid work after age 65: A Swedish population-based study covering 1995, 2000, 2005 and 2010.

    Science.gov (United States)

    Farrants, K; Marklund, S; Kjeldgård, L; Head, J; Alexanderson, K

    2018-05-01

    Extending working life into older age groups is discussed in many countries. However, there is no knowledge about how this affects rates of sick leave. The aim of this work was to investigate rates of sick leave among people in paid work after retirement age and if such rates have changed over time. Swedish nationwide register data on people aged >65 years and living in Sweden in 1995, 2000, 2005 and 2010 were analysed. All people with a sufficiently high work income to be eligible for public sick leave benefits were included. The proportions in paid work and compensated rates of sick leave for people aged 66-70 and ≥71 were analysed by sex, educational level, country of birth, living area, and employment type and sector. The percentage of people in paid work at ages 66-70 years increased from Women had higher rates of sick leave than men in 2005 and 2010, but lower in 1995 and 2000. In 2010, the rates of sick leave were similar between employees and the self-employed, and higher among employees in the public sector than among employees in the private sector. Rates of sick leave among workers aged >65 years were lower in 2010 than in 1995, despite much higher rates of labour market participation in 2010.

  12. Socio-demographic and work-related risk factors for medium- and long-term sickness absence among Italian workers.

    Science.gov (United States)

    d'Errico, Angelo; Costa, Giuseppe

    2012-10-01

    Few studies investigated determinants of sickness absence in representative samples of the general population, none of which in Italy. Aim of this study was to assess influence and relative importance of socio-demographic and work-related characteristics on medium- and long-term sickness absence in a random sample of Italian workers. Approximately 60,000 workers participating in a national survey in 2007 were interviewed regarding sickness absence during the whole previous week, and on socio-demographics, employment characteristics and exposure to a set of physical and psychosocial hazards in the workplace. The association between sickness absence and potential determinants was estimated by multivariable logistic regression models stratified by gender. From the final multivariate models, in both genders sickness absence was statistically significantly associated with tenure employment, working in larger firms, exposure to risk of injury and to bullying or discrimination and, among employees, with shift work. In males, sickness absence was also associated with lower education, employment in the public administration and with exposure to noise or vibration, whereas among women also with manual work and ergonomic factors. In both genders, the attributable fraction for employment-related characteristics was higher than that for socio-demographic ones. The association with tenure or salaried jobs, and with employment in larger firms or in the public sector suggests that, besides illness, job security is the most important determinant of sickness absence, consistently with the results of previous studies. However, our results indicate that a reduction in exposure to workplace hazards may contribute to reduce absenteeism.

  13. Mental and physical health-related functioning mediates between psychological job demands and sickness absence among nurses.

    Science.gov (United States)

    Roelen, Corné; van Rhenen, Willem; Schaufeli, Wilmar; van der Klink, Jac; Magerøy, Nils; Moen, Bente; Bjorvatn, Bjørn; Pallesen, Ståle

    2014-08-01

    To investigate whether health-related functioning mediates the effect of psychological job demands on sickness absence in nurses. Nurses face high job demands that can have adverse health effects resulting in sickness absence. Prospective cohort study with 1-year follow-up. Data for 2964 Norwegian nurses were collected in the period 2008-2010. At baseline, psychological job demands were measured with the Demand-Control-Support Questionnaire. Health-related functioning was assessed by the Mental Composite Score and the Physical Composite Score of the SF-12 Health Survey (2nd version). Sickness absence (no = 0, yes = 1) was self-reported at 1-year follow-up. Interaction and mediation analyses were conducted stratified by tenure (6 years) as a registered nurse. A total of 2180 nurses (74%) with complete data were eligible for analysis. A significant three-way interaction between job demands, control and support was found in newly licensed nurses (tenure sickness absence at 1-year follow-up. This association was substantially weakened when Mental Composite Score and Physical Composite Score were introduced as mediator variables, indicating a partial mediation effect that was particularly pronounced in newly licensed nurses. Psychological job demands did not modify the effect of health-related functioning on sickness absence. Both mental and physical health-related functioning mediated between psychological job demands and sickness absence. Nurse managers should pay attention to health-related functioning, because poor health-related functioning may predict sickness absence, especially in newly licensed nurses. © 2013 John Wiley & Sons Ltd.

  14. Relationship between Comorbid Health Problems and Musculoskeletal Disorders Resulting in Musculoskeletal Complaints and Musculoskeletal Sickness Absence among Employees in Korea.

    Science.gov (United States)

    Baek, Ji Hye; Kim, Young Sun; Yi, Kwan Hyung

    2015-06-01

    To investigate the relationship between musculoskeletal disorders and comorbid health problems, including depression/anxiety disorder, insomnia/sleep disorder, fatigue, and injury by accident, and to determine whether certain physical and psychological factors reduce comorbid health problems. In total, 29,711 employees were selected from respondents of the Third Korean Working Conditions Survey and categorized into two groups: Musculoskeletal Complaints or Musculoskeletal Sickness Absence. Four self-reported health indicators (overall fatigue, depression/anxiety, insomnia/sleep disorder, and injury by accident) were selected as outcomes, based on their high prevalence in Korea. We used multiple logistic regression analysis to determine the relationship between comorbid health problems, musculoskeletal complaints, and sickness absence. The prevalence of musculoskeletal complaints and musculoskeletal sickness absence due to muscular pain was 32.26% and 0.59%, respectively. Compared to the reference group, depression/anxiety disorder and overall fatigue were 5.2-6.1 times more prevalent in the Musculoskeletal Complaints Group and insomnia/sleep disorder and injury by accident were 7.6-11.0 times more prevalent in the Sickness Absence Group. When adjusted for individual and work-related physical factors, prevalence of all four comorbid health problems were slightly decreased in both groups. Increases in overall fatigue and depression/anxiety disorder were observed in the Musculoskeletal Complaints Group, while increases in insomnia/sleep disorder and injury by accident were observed in the Sickness Absence Group. For management of musculoskeletal complaints and sickness absence in the workplace, differences in health problems between employees with musculoskeletal complaints and those with sickness absence as well as the physical and psychological risk factors should be considered.

  15. Suggested classification of acute radiation sickness

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Guo; Mingyue, Zhu; Zhiqin, Zhao

    1984-08-01

    Acute radiation sickness is usually classified into three types. Over the last decade, we have been engaged in experimental studies on the classification of this syndrome. Our findings from these studies, however, point to the fact that between the hemopoietic and intestinal types, and between the intestinal and cerebral types there are transitive forms, namely, hemopoieto-intestinal type and cardio-vascular type, respectively. In this article the required radiation doses and the clinical courses of these transitive forms with special emphasis on their histological and clinical manifestations are described. In case of the hemopoieto-intestinal form, histological examination may reveal residual crypts and typical ''abnormal cells'' in the intestinal mucosa, and clinical manifestations include almost the whole spectrum of symptoms and signs of infection and hemorrhage. The watery stool in pink colour may be specific and helpful in diagnosis. In case of the cardio-vascular form, shock may occur immediately after exposure, and histological examination may show myocardial edema, hemorrhage, cell-infiltration and even necrosis. We propose that the acute radiation sickness should be divided into 5 forms, namely, hemopoietic, hemopoieto-intestinal, intestinal, cardio-vascular and cerebral types. Accurate diagnosis can only be made by taking an comprehensive view of radiation dose, clinical course, clinical manifestations and histological findings. (author).

  16. A suggested classification of acute radiation sickness

    International Nuclear Information System (INIS)

    Guo Yao; Zhu Mingyue; Zhao Zhiqin

    1984-01-01

    Acute radiation sickness is usually classified into three types. Over the last decade, we have been engaged in experimental studies on the classification of this syndrome. Our findings from these studies, however, point to the fact that between the hemopoietic and intestinal types, and between the intestinal and cerebral types there are transitive forms, namely, hemopoieto-intestinal type and cardio-vascular type, respectively. In this article the required radiation doses and the clinical courses of these transitive forms with special emphasis on their histological and clinical manifestations are described. In case of the hemopoieto-intestinal form, histological examination may reveal residual crypts and typical ''abnormal cells'' in the intestinal mucosa, and clinical manifestations include almost the whole spectrum of symptoms and signs of infection and hemorrhage. The watery stool in pink colour may be specific and helpful in diagnosis. In case of the cardio-vascular form, shock may occur immediately after exposure, and histological examination may show myocardial edema, hemorrhage, cell-infiltration and even necrosis. We propose that the acute radiation sickness should be divided into 5 forms, namely, hemopoietic, hemopoieto-intestinal, intestinal, cardio-vascular and cerebral types. Accurate diagnosis can only be made by taking an comprehensive view of radiation dose, clinical course, clinical manifestations and histological findings. (author)

  17. Late stage infection in sleeping sickness.

    Directory of Open Access Journals (Sweden)

    Hartwig Wolburg

    Full Text Available At the turn of the 19(th century, trypanosomes were identified as the causative agent of sleeping sickness and their presence within the cerebrospinal fluid of late stage sleeping sickness patients was described. However, no definitive proof of how the parasites reach the brain has been presented so far. Analyzing electron micrographs prepared from rodent brains more than 20 days after infection, we present here conclusive evidence that the parasites first enter the brain via the choroid plexus from where they penetrate the epithelial cell layer to reach the ventricular system. Adversely, no trypanosomes were observed within the parenchyma outside blood vessels. We also show that brain infection depends on the formation of long slender trypanosomes and that the cerebrospinal fluid as well as the stroma of the choroid plexus is a hostile environment for the survival of trypanosomes, which enter the pial space including the Virchow-Robin space via the subarachnoid space to escape degradation. Our data suggest that trypanosomes do not intend to colonize the brain but reside near or within the glia limitans, from where they can re-populate blood vessels and disrupt the sleep wake cycles.

  18. The study of thrombocytopenia in sick neonates

    International Nuclear Information System (INIS)

    Aman, I.; Hassan, K.A.; Ahmad, T.M.

    2004-01-01

    Objective: To determine the number of cases and manifestations of thrombocytopenia in sick neonates. Subjects and Methods: A total of 365 neonates from 0-28 days of age admitted with different clinical problems irrespective of birth weight and gestational age were evaluated for thrombocytopenia. These neonates were categorized into five different groups (A-E), which were of neonatal infections, asphyxia neonatorum, preterm and smallness for gestational age, jaundice and miscellaneous respectively. Results: Out of 365 cases, 88 were found to have thrombocytopenia (platelet counts < 150,000 per mm/sup 3/) which was 24.1% of the total. In group A (neonatal infections), out of 152 neonates, 62 had low platelet counts (40.78%). In group B (neonatal asphyxia), out of 90 only 11 had thrombocytopenia (12.2%). In group C (preterm and small for gestational age), out of 60 cases only 9 had thrombocytopenia. In group D (jaundice), all 33 cases had normal platelet counts. In group E (miscellaneous), out of 30 cases only 6 had thrombocytopenia. The common manifestations in thrombocytopenic babies were petechiae and bruises followed by gastrointestinal hemorrhages. The percentage of manifest thrombocytopenia cases was 56.8% and of occult thrombocytopenia 43.1 %. Conclusion: The leading causes of thrombocytopenia in sick neonates are infections, asphyxia, complicated pre- maturity and smallness for gestational age. Apart from the platelet counts the bleeding mainfestations also depend upon the underlying ailments. (author)

  19. Effect of domperidone on radiation sickness

    Energy Technology Data Exchange (ETDEWEB)

    Sakakibara, T; Sato, K [Nihon Univ., Tokyo. School of Medicine; Watari, T; Tanaka, T; Furuta, A

    1981-07-01

    Domperidone was administered to 95 patients with radiation sickness following radiotherapy for various cancers. The chest and the mediastinum were irradiated in 43 patients, the upper and lower abdomen in 40 patients, and the head, neck, and supraclavicular region in 12 patients. As to radiation source, x-ray was used for 46 patients, ..gamma..-ray for 41 patients, electron beam for 3 patients, and more than one radiation was used for 5 patients. The dose given before the onset of radiation sickness totaled 3000 rad in 20 patients, 1000 rad -- 3000 rad in 41, and less than 1000 rad in 34. Domperidone was given to the patients one tablet (5 mg or 10 mg) P.O., 3 times per day before meals, for 1 -- 2 weeks. The overall effective rate of the drug was 68.4%. The 10 mg tablets were slightly more effective than the 5 mg ones. In the patients who were given the drug in a dose of 10 mg, the ameliorating rate of subjective symptoms was 68.1% for nausea, 88.9% for vomiting, 44.6% for anorexia, 17.5% for general fatigue, and 69.2% for dizziness. Laboratory findings showed no abnormal effects of the drug. One patient had itching with eruptions, which, however, was mild and disappeared immediately after withdrawal of the medication.

  20. Experimental Investigation of the Resistance Performance and Heave and Pitch Motions of Ice-Going Container Ship Under Pack Ice Conditions

    Science.gov (United States)

    Guo, Chun-yu; Xie, Chang; Zhang, Jin-zhao; Wang, Shuai; Zhao, Da-gang

    2018-04-01

    In order to analyze the ice-going ship's performance under the pack ice conditions, synthetic ice was introduced into a towing tank. A barrier using floating cylinder in the towing tank was designed to carry out the resistance experiment. The test results indicated that the encountering frequency between the ship model and the pack ice shifts towards a high-velocity point as the concentration of the pack ice increases, and this encountering frequency creates an unstable region of the resistance, and the unstable region shifts to the higher speed with the increasing concentration. The results also showed that for the same speed points, the ratio of the pack ice resistance to the open water resistance increases with the increasing concentration, and for the same concentrations, this ratio decreases as the speed increases. Motion characteristics showed that the mean value of the heave motion increases as the speed increases, and the pitch motion tends to increase with the increasing speed. In addition, the total resistance of the fullscale was predicted.

  1. Explaining the social gradient in sickness absence: a study of a general working population in Sweden.

    Science.gov (United States)

    Löve, Jesper; Hensing, Gunnel; Holmgren, Kristina; Torén, Kjell

    2013-06-05

    Some previous studies have proposed potential explanatory factors for the social gradient in sickness absence. Yet, this research area is still in its infancy and in order to comprise the full range of socioeconomic positions there is a need for studies conducted on random population samples. The main aim of the present study was to investigate if somatic and mental symptoms, mental wellbeing, job strain, and physical work environment could explain the association between low socioeconomic position and belonging to a sample of new cases of sick-listed employees. This study was conducted on one random working population sample (n = 2763) and one sample of newly sick-listed cases of employees (n = 3044), drawn from the same random general population in western Sweden. Explanatory factors were self-rated 'Somatic and mental symptoms', 'Mental well-being', 'job strain', and 'physical work conditions' (i.e. heavy lifting and awkward work postures). Multiple logistic regression analyses were used. Somatic and mental symptoms, mental well-being, and job strain, could not explain the association between socioeconomic position and sickness absence in both women and men. However, physical work conditions explained the total association in women and much of this association in men. In men the gradient between Non-skilled manual OR 1.76 (1.24;2.48) and Skilled manual OR 1.59 (1.10;2.20), both in relation to Higher non-manual, remained unexplained. The present study strengthens the scientific evidence that social differences in physical work conditions seem to comprise a key element of the social gradient in sickness absence, particularly in women. Future studies should try to identify further predictors for this gradient in men.

  2. Parental availability for the care of sick children.

    Science.gov (United States)

    Heymann, S J; Earle, A; Egleston, B

    1996-08-01

    Parents have always played a critical role in the care of sick children. Although parents' roles remain crucial to children's health, parental availability has declined during the past half century. The percentage of women with preschool children who work has risen almost fivefold in 45 years from 12% in 1947 to 58% in 1992. The percentage of women in the paid work force with school-aged children has almost tripled in the same period, from 27.3% to 75.9%. Research has examined the effects of a variety of parental work conditions on children. However, past research has not examined how working conditions affect the ability of parents to care for their sick children. In this article, we examine how often the children of working parents get sick and whether parents receive enough paid leave to care for their sick children. This analysis makes use of two national surveys, which provide complementary information regarding the care of sick children. The National Longitudinal Survey of Youth is a longitudinal survey of a nationally representative probability sample of 12,686 men and women; the National Medical Expenditure Survey is a panel survey of 34,459 people. First, we estimated the family illness burden. Second, we looked in detail at the number of days of sick leave mothers had. Third, we examined whether mothers who had sick leave had it consistently during a 5-year period. Finally, we conducted a logistic regression to determine what factors were significant predictors of both lacking sick leave. More than one in three families faced a family illness burden of 2 weeks or more each year. Yet, 28% of mothers had sick leave none of the time they were employed between 1985 and 1990. Employed mothers of children with chronic conditions had less sick leave than other employed mothers. Thirty-six percent of mothers whose children had chronic conditions had sick leave none of the time they were employed. Although 20% of working parents who did not live in poverty lacked

  3. Analyzing sickness absence with statistical models for survival data

    DEFF Research Database (Denmark)

    Christensen, Karl Bang; Andersen, Per Kragh; Smith-Hansen, Lars

    2007-01-01

    OBJECTIVES: Sickness absence is the outcome in many epidemiologic studies and is often based on summary measures such as the number of sickness absences per year. In this study the use of modern statistical methods was examined by making better use of the available information. Since sickness...... absence data deal with events occurring over time, the use of statistical models for survival data has been reviewed, and the use of frailty models has been proposed for the analysis of such data. METHODS: Three methods for analyzing data on sickness absences were compared using a simulation study...... involving the following: (i) Poisson regression using a single outcome variable (number of sickness absences), (ii) analysis of time to first event using the Cox proportional hazards model, and (iii) frailty models, which are random effects proportional hazards models. Data from a study of the relation...

  4. Explanation of diagnosis criteria for radiation sickness from internal exposure

    International Nuclear Information System (INIS)

    Xing Zhiwei; Jiang Enhai; Du Jianying; Bai Guang

    2012-01-01

    A revised edition of the Diagnostic Criteria for Radiation Sickness from Internal Exposure has been approved and issued by the Ministry of Health. It is necessary to research the internal radiation sickness to adapt to the current serious anti-terrorism situation. This standard was enacted based on the extensive research of related literature, from which 12 cases with internal radiation sickness and screened out were involving 7 types of radionuclide. The Development of Emergency Response Standard Extension Framework: Midterm Evaluation Report is the main reference which approved by the International Atomic Energy Agency and World Health Organization. This amendment contains many new provisions such as internal radiation sickness effects models and threshold dose, and the appendix added threshold dose of serious deterministic effects induced by radionuclide intake and radiotoxicology parameters of some radionuclides. In order to understand and implement this standard, and to diagnose and treat the internal radiation sickness correctly, the contents of this standard were interpreted in this article. (authors)

  5. Sickness benefit cuts mainly affect blue-collar workers.

    Science.gov (United States)

    Aaviksoo, E; Kiivet, R-A

    2014-08-01

    To analyse the impact of sick-pay cuts on the use of sickness absence by employees of different socioeconomic groups. In 2009 cuts in sick pay were implemented in reaction to an economic crisis in Estonia. Nationwide health survey data from the years 2004, 2006, 2008, and 2010 were used to evaluate sickness absence among blue-collar and white-collar workers. The dataset comprised 7,449 employees of 20-64 years of age. Difference in prevalence of absentees before and after the reform was assessed using the chi-squared test. Odds ratios (OR) for sickness absence were calculated in a multivariate logistic regression model. After the reform, the proportion of blue-collar workers who had been on sick leave decreased from 51% to 40% (pgender, age, self-rated health, and presence of chronic disease, especially among those with low incomes; in white-collar employees it reached statistical significance only in those with good self-rated health (p=0.033). In a multivariate model the odds of having lower sickness absence were highly significant only in blue-collar employees (OR 0.63; 95% confidence interval 0.51-0.77, p<0.001). The cuts in sickness benefits had a major impact on the use of sickness absence by blue-collar employees with low salaries. This indicates that lower income was a major factor hindering the use of sick leave as these employees are most vulnerable to the loss of income. © 2014 the Nordic Societies of Public Health.

  6. How physicians have learned to handle sickness-certification cases.

    Science.gov (United States)

    Löfgren, Anna; Silén, Charlotte; Alexanderson, Kristina

    2011-05-01

    Sickness absence is a common ''prescription'' in health care in many Western countries. Despite the significance of sick-listing for the life situation of patients, physicians have limited training in how to handle sickness-certification cases and the research about sickness-certification practices is scarce. Gain knowledge on physicians' learning regarding management of sickness certification of patients in formal, informal, and non-formal learning situations, respectively, and possible changes in this from 2004 to 2008. Data from two comprehensive questionnaires to physicians in Sweden about their sickness-certification practice in 2004 (n = 7665) and 2008 (n = 36,898); response rates: 71% and 61%, respectively. Answers from all the physicians ≤64 years old and who had sickness certification tasks (n = 4019 and n = 14,210) were analysed. ratings of importance of different types of learning situations for their sickness-certification competence. Few physicians stated that formal learning situations had contributed to a large or fairly large extent to their competence in sickness certification, e.g. undergraduate studies had done that for 17%, internship for 37%, and resident training for 46%, respectively. Contacts with colleagues had been helpful for 65%. One-third was helped by training arranged by social insurance offices. There was a significant increase between 2004 and 2008 in all items related to formal and non-formal learning situations, while there were no changes regarding informal learning situations. This study of all physicians in Sweden shows that physicians primarily attain competence in sickness certification in their daily clinical practice; through contacts with colleagues and patients.

  7. Medically certified sickness absence among health care workers.

    Science.gov (United States)

    Khawaja, Rajab Ali; Sikander, Raheel; Khawaja, Asad Ali; Jareno, Rechel Joy Macadaan; Halepota, Aurangzeb Taj

    2012-09-01

    To compare the days and spells of sickness absence among males versus females and Saudi nationals versus expatriate employees of King Khalid University Hospital, Riyadh, and to identify the cause of sickness absence. The cross-sectional, descriptive study comprised 3117 King Khalid University Hospital employees. Records of physician-certified sickness absence from January 1 to June 30, 2009, were obtained from the employee health clinic's register. Absence rate, frequency, duration and severity were assessed and compared between genders and nationalities, and causes were noted. SPSS version 16 and student's t test were used for statistical analyses and comparison. A total of 377 (12.1 %) employees had 416 spells of sickness absence with 639 sick-off days (mean: 1.54 +/- 0.85). The probability of sickness absence was higher among Saudi (OR=1.33) and female (OR=1.39) employees. The association of sickness absence was not found among the absentees with either gender (p= 0.335) or nationality (p = 0.086). Almost all spells of sick-off days were of short duration. Longer spells were mainly due to chicken pox which was found to be more among the expatriates. Heavy absenteeism was found only among the Saudis. The most common causes of sickness absence were acute upper respiratory infection, diseases of musculoskeletal system and the digestive system. The rate, frequency and duration of absence due to sickness in the study were higher among Saudi and female employees. The rate of absence, with passage of time, has increased significantly among Saudi nationals.

  8. Sickness absence due to specific mental diagnoses and all-cause and cause-specific mortality: a cohort study of 4.9 million inhabitants of Sweden.

    Directory of Open Access Journals (Sweden)

    Ellenor Mittendorfer-Rutz

    Full Text Available BACKGROUND: Despite the magnitude and increase of sickness absence due to mental diagnoses, little is known regarding long-term health outcomes. The aim of this nationwide population-based, prospective cohort study was to investigate the association between sickness absence due to specific mental diagnoses and the risk of all-cause and cause-specific mortality. METHODS: A cohort of all 4 857 943 individuals living in Sweden on 31.12.2004 (aged 16-64 years, not sickness absent, or on retirement or disability pension, was followed from 01.01.2005 through 31.12.2008 for all-cause and cause-specific mortality (suicide, cancer, circulatory disease through linkage of individual register data. Individuals with at least one new sick-leave spell with a mental diagnosis in 2005 were compared to individuals with no sickness absence. Hazard ratios (HR and 95% confidence intervals (CI were estimated by Cox regression, adjusting for age, sex, education, country of birth, family situation, area of residence, and pre-existing morbidity (diagnosis-specific hospital inpatient (2000-2005 and outpatient (2001-2005 care. RESULTS: In the multivariate analyses, mental sickness absence in 2005 was associated with an increased risk for all-cause mortality: HR: 1.65, 95% CI: 1.47-1.86 in women and in men: 1.73, 1.57-1.91; for suicide, cancer (both smoking and non-smoking related as well as mortality due to circulatory disease only in men. Estimates for cause-specific mortality ranged from 1.48 to 3.37. Associations with all-cause mortality were found for all mental sickness absence diagnostic groups studied. CONCLUSIONS: Knowledge about the prognosis of patients sickness absent with specific mental diagnoses is of crucial clinical importance in health care. Sickness absence due to specific mental diagnoses may here be used as a risk indictor for subsequent mortality.

  9. Risk markers of all-cause and diagnosis-specific disability pension--a prospective cohort study of individuals sickness absent due to stress-related mental disorders

    DEFF Research Database (Denmark)

    Ishtiak-Ahmed, Kazi; Perski, Aleksander; Mittendorfer-Rutz, Ellenor

    2014-01-01

    BACKGROUND: Stress-related mental disorders rank among the leading causes of sickness absence in several European countries. The aim of this study was to investigate predictors of all-cause and diagnosis-specific disability pension in sickness absentees with stress-related mental disorders. METHO....... The variation in the effect of risk markers with regard to age and diagnosis of disability pension speaks in favour of the importance of a person-centered approach in treatment and rehabilitation....

  10. The impact of the HDI on the association of psychosocial work demands with sickness absence and presenteeism.

    Science.gov (United States)

    Muckenhuber, Johanna; Burkert, Nathalie; Dorner, Thomas E; Großschädl, Franziska; Freidl, Wolfgang

    2014-10-01

    The purpose of this study was to determine whether psychosocial work demands have a different impact on sickness absence and presenteeism in countries with a high vs. countries with a low Human Development Index (HDI). This article is based on an analysis of the fifth European Working Conditions Survey. We investigated single items as well as complex constructs and indices. Sickness absence and presenteeism were measured as outcome variables. Following the model of Karasek and Theorell, we measured the HDI at the macro level and psychosocial job demands at the micro level as independent variables. The multivariate multilevel analysis reveals a significant association between the HDI and the number of days recorded for sickness absence. In countries with a higher HDI, people report a lower number of days with sickness absence. Higher psychosocial job demands are associated with poorer health. There are significant cross-level interaction effects between psychosocial job demands and the HDI for these associations. Psychosocial job demands are stronger associated with sickness absence and presenteeism in high-HDI than in low-HDI countries. We argue that Public Health Actions that are connected to work characteristics need to take into consideration the level of HDI of the countries. In low- and high-HDI countries, different actions could be necessary to reach the needs of the working population. © The Author 2013. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  11. Effect of Miradol (Sulpiride) on radiation sickness studied by a double-blind test

    International Nuclear Information System (INIS)

    Murakami, Yuko; Morita, Shinroku

    1981-01-01

    Effect of Miradol on radiation sickness was investigated by a double-blind test. The rate of ''effective'' was 66.7% of the patients given Miradol and 20.1% of those given placebo (p < 0.01). The drug was especially effective on the patients chiefly complaining of nausea and vomiting. Placebo was also effective in some of the cases with appetite loss etc. (Ueda, J.)

  12. The differential role of pain, work characteristics and pain and sick leave in occupational settings

    OpenAIRE

    GHELDOF, Els; VINCK, Jan; Vlaeyen, J.; Hidding, A.; Crombez, G.

    2005-01-01

    This cross-sectional questionnaire study investigated the role of pain (pain severity, radiating pain), work characteristics (physical workload, job stressors, job satisfaction), negative affect and pain-related fear in accounting for low back pain (LBP) and sick leave (SL) in 1294 employees from 10 companies in Belgium and the Netherlands. An increased risk for short-term LBP (1–30 days during the last year) was observed for workers reporting high physical workload (OR=2.39), high task exert...

  13. Predictors of Sick Sinus Syndrome in Patients after Successful Radiofrequency Catheter Ablation of Atrial Flutter

    OpenAIRE

    Song, Changho; Jin, Moo-Nyun; Lee, Jung-Hee; Kim, In-Soo; Uhm, Jae-Sun; Pak, Hui-Nam; Lee, Moon-Hyoung; Joung, Boyoung

    2014-01-01

    Purpose The identification of sick sinus syndrome (SSS) in patients with atrial flutter (AFL) is difficult before the termination of AFL. This study investigated the patient characteristics used in predicting a high risk of SSS after AFL ablation. Materials and Methods Out of 339 consecutive patients who had undergone radiofrequency ablation for AFL from 1991 to 2012, 27 (8%) had SSS (SSS group). We compared the clinical characteristics of patients with and without SSS (n=312, no-SSS group). ...

  14. 19 CFR 210.15 - Motions.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Motions. 210.15 Section 210.15 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.15 Motions. (a) Presentation and disposition. (1) During the period...

  15. Visualization of Kepler's Laws of Planetary Motion

    Science.gov (United States)

    Lu, Meishu; Su, Jun; Wang, Weiguo; Lu, Jianlong

    2017-01-01

    For this article, we use a 3D printer to print a surface similar to universal gravitation for demonstrating and investigating Kepler's laws of planetary motion describing the motion of a small ball on the surface. This novel experimental method allows Kepler's laws of planetary motion to be visualized and will contribute to improving the…

  16. Work and family: associations with long-term sick-listing in Swedish women – a case-control study

    Directory of Open Access Journals (Sweden)

    Sandmark Hélène

    2007-10-01

    Full Text Available Abstract Background The number of Swedish women who are long-term sick-listed is high, and twice as high as for men. Also the periods of sickness absence have on average been longer for women than for men. The objective of this study was to investigate the associations between factors in work- and family life and long-term sick-listing in Swedish women. Methods This case-control study included 283 women on long-term sick-listing ≥90 days, and 250 female referents, randomly chosen, living in five counties in Sweden. Bivariate and multivariate logistic regression analyses with odds ratios were calculated to estimate the associations between long-term sick-listing and factors related to occupational work and family life. Results Long-term sick-listing in women is associated with self-reported lack of competence for work tasks (OR 2.42 1.23–11.21 log reg, workplace dissatisfaction (OR 1.89 1.14–6.62 log reg, physical workload above capacity (1.78 1.50–5.94, too high mental strain in work tasks (1.61 1.08–5.01 log reg, number of employers during work life (OR 1.39 1.35–4.03 log reg, earlier part-time work (OR 1.39 1.18–4.03 log reg, and lack of influence on working hours (OR 1.35 1.47–3.86 log reg. A younger age at first child, number of children, and main responsibility for own children was also found to be associated with long-term sick-listing. Almost all of the sick-listed women (93% wanted to return to working life, and 54% reported they could work immediately if adjustments at work or part-time work were possible. Conclusion Factors in work and in family life could be important to consider to prevent women from being long-term sick-listed and promote their opportunities to remain in working life. Measures ought to be taken to improve their mobility in work life and control over decisions and actions regarding theirs lives.

  17. Home care services for sick children

    DEFF Research Database (Denmark)

    Castor, Charlotte; Hallström, Inger; Hansson, Eva Helena

    2017-01-01

    as challenging for healthcare professionals in home care services used to providing care predominately for adults. DESIGN: An inductive qualitative design. METHOD: Seven focus group interviews were performed with 36 healthcare professionals from multidisciplinary home care services. Data were analysed stepwise......AIMS AND OBJECTIVES: To explore healthcare professionals' conceptions of caring for sick children in home care services. BACKGROUND: Families often prefer home care to hospital care, and the number of home care services for children is increasing. Caring for children at home has been recognised...... using a phenomenographic analysis. RESULTS: Three description categories emerged: "A challenging opportunity", "A child perspective", and "Re-organise in accordance with new prerequisites." Providing home care services for children was conceived to evoke both professional and personal challenges...

  18. Two activities with a simple model of the solar system: discovering Kepler’s 3rd law and investigating apparent motion of Venus

    Science.gov (United States)

    Rovšek, Barbara; Guštin, Andrej

    2018-01-01

    An astronomy ‘experiment’ composed of three parts is described in the article. Being given necessary data a simple model of inner planets of the solar system is made in the first part with planets’ circular orbits using appropriate scale. In the second part revolution of the figurines used as model representations of the planets along their orbits is observed. In the third part of activity apparent motion of Venus with respect to the observer on the Earth is studied. In the second part of the paper problems are given, which relate to experimental activities and are designed to test if learning outcomes of the experiment have been achieved: if correlation between orbital radius and orbital velocity has been perceived, concepts related to motion of Venus as observed from the Earth have been acquired and periodicity recognized. Described astronomy ‘experiment’ was one of the three science experiments given to 11 and 12 years old students prior to Slovene science competition in 2017 (the call for competition is at www.dmfa.si, guidelines for the experiment (in Slovene) can be found at www.kresnickadmfa.si/files/2016/07/poskus_1617_r67p1_S.pdf). At the end of the paper the results obtained at competition are presented.

  19. Associations between work stress, alcohol consumption and sickness absence.

    Science.gov (United States)

    Vasse, R M; Nijhuis, F J; Kok, G

    1998-02-01

    To test an interactional model on the associations between work stressors, perceived stress, alcohol consumption and sickness absence. Cross-sectional survey. The study was part of a Worksite Health Project including an Employee Assistance Programme and a Health Promotion Programme in the Netherlands. Participants were blue-collar workers from two Municipal Garbage Collecting Departments and white-collar workers from a Pharmaceutical Company (N = 471). Measurements included socio-demographic characteristics (gender, age, education, marital status), work stressors, perceived stress, alcohol consumption and sickness absence. Type of work-site (blue- or white-collar) and smoking behaviour were used as covariates. Regression analyses resulted in three major findings. First, in the presence of stress, abstinence increased the risk of sickness absence compared with moderate drinking. We failed to find a significant relationship between excessive drinking and sickness absence. Secondly, stress mediated the associations between stressor and alcohol consumption, and between stressor and sickness absence, although stressors also directly predicted sickness absence. The association between abstinence and sickness absence could reflect medical problems of abstainers or a lack of skills for coping with stress. The failure to find a significant detrimental effect of excessive drinking may have been due to use of a low threshold for excessive drinking and/or low power. Prospective studies are needed to gain insight in causal relationships between the variables concerned.

  20. Work health determinants in employees without sickness absence.

    Science.gov (United States)

    Schell, E; Theorell, T; Nilsson, B; Saraste, H

    2013-01-01

    Working ability is known to be related to good physical condition, clear work tasks, positive feedback and other occupational, organizational and psychosocial factors. In Sweden, high levels of sickness absence are due to stress-related disorders and musculoskeletal pain. To identify work health characteristics in a working population with a large variety of professional skills and occupational tasks. Employers' data on occupation, sickness absence, age and gender in a working population of 11 occupational groups and questionnaire responses regarding work-organization, environment, work stress, pain, health, and socio-demographic factors were collected. Employees with no history of sick-leave were compared with those with a history of sick-leave (1-182 days, mean 25 days). Of 2641 employees, 1961 participated. Those with no history of sick-leave reported less work-related pain, work-related stress, sleep disturbances, worry about their health, 'sick-presenteeism', monotonous work, bent and twisted working positions and exposure to disturbing noise than those with a history of sick-leave (P health, support from superiors, having influence on their working hours and evening and week-end working, longer working hours per week (P health and less neck, shoulder and back pain and more support from their superiors and influence on their working hours.

  1. Markerless motion estimation for motion-compensated clinical brain imaging

    Science.gov (United States)

    Kyme, Andre Z.; Se, Stephen; Meikle, Steven R.; Fulton, Roger R.

    2018-05-01

    Motion-compensated brain imaging can dramatically reduce the artifacts and quantitative degradation associated with voluntary and involuntary subject head motion during positron emission tomography (PET), single photon emission computed tomography (SPECT) and computed tomography (CT). However, motion-compensated imaging protocols are not in widespread clinical use for these modalities. A key reason for this seems to be the lack of a practical motion tracking technology that allows for smooth and reliable integration of motion-compensated imaging protocols in the clinical setting. We seek to address this problem by investigating the feasibility of a highly versatile optical motion tracking method for PET, SPECT and CT geometries. The method requires no attached markers, relying exclusively on the detection and matching of distinctive facial features. We studied the accuracy of this method in 16 volunteers in a mock imaging scenario by comparing the estimated motion with an accurate marker-based method used in applications such as image guided surgery. A range of techniques to optimize performance of the method were also studied. Our results show that the markerless motion tracking method is highly accurate (brain imaging and holds good promise for a practical implementation in clinical PET, SPECT and CT systems.

  2. Health-related behaviours and sickness absence from work.

    Science.gov (United States)

    Laaksonen, M; Piha, K; Martikainen, P; Rahkonen, O; Lahelma, E

    2009-12-01

    To compare associations of health-related behaviours with self-certified and medically confirmed sickness absence, and to examine whether these associations can be explained by psychosocial and physical working conditions and occupational social class. The study included 5470 female and 1464 male employees of the City of Helsinki surveyed in 2000-2002. These data were linked to sickness absence records until the end of 2005, providing a mean follow-up time of 3.9 years. Poisson regression analysis was used to examine associations of smoking, alcohol use, physical activity, dietary habits and relative weight (body mass index) with self-certified (1-3 days) and medically confirmed (> or =4 days) absence spells. Population attributable fractions (PAFs) were calculated to quantify the sickness absence burden related to the behaviours. Smoking and high relative weight were most strongly associated with sickness absence, while the associations of other studied health-related behaviours were weaker. The associations were stronger for medically confirmed sickness absence spells for which heavy smoking and obesity more than doubled the risk of sickness absence in men and nearly doubled it in women. Adjusting for psychosocial working conditions had little or no effect on the associations. Physical working conditions and social class somewhat attenuated the associations, especially for smoking and relative weight. In self-certified sickness absence the PAF for smoking (16.4 in men, 10.3 in women) was largest, while in medically confirmed absence relative weight had the largest PAF (23.5 in men, 15.0 in women). Health-related behaviours, smoking and high relative weight in particular, were associated with subsequent sickness absence independently of psychosocial and physical working conditions and social class. Decreasing smoking and relative weight is likely to provide important gains in work ability and reduce sickness absence.

  3. Auditory Motion Elicits a Visual Motion Aftereffect

    Directory of Open Access Journals (Sweden)

    Christopher C. Berger

    2016-12-01

    Full Text Available The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect—an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  4. Auditory Motion Elicits a Visual Motion Aftereffect.

    Science.gov (United States)

    Berger, Christopher C; Ehrsson, H Henrik

    2016-01-01

    The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect-an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  5. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  6. INTERACTIVE MOTION PLATFORMS AND VIRTUAL REALITY FOR VEHICLE SIMULATORS

    Directory of Open Access Journals (Sweden)

    Evžen Thöndel

    2017-12-01

    Full Text Available Interactive motion platforms are intended for vehicle simulators, where the direct interaction of the human body is used for controlling the simulated vehicle (e.g. bicycle, motorbike or other sports vehicles. The second use of interactive motion platforms is for entertainment purposes or fitness. The development of interactive motion platforms reacts to recent calls in the simulation industry to provide a device, which further enhances the virtual reality experience, especially with connection to the new and very fast growing business in virtual reality glasses. The paper looks at the design and control of an interactive motion platform with two degrees of freedom to be used in virtual reality applications. The paper provides the description of the control methods and new problems related to the virtual reality sickness are discussed here.

  7. Job mismatching, unequal opportunities and long-term sickness absence in female white-collar workers in Sweden.

    Science.gov (United States)

    Sandmark, Hélène

    2009-01-01

    To investigate associations between long-term sick-listing and factors at work and in family life. Associations were investigated in a cross-sectional case-referent study. The study base included women in white-collar jobs, aged 30-55 years, living in three urban areas in Sweden between February 2004 and October 2004. A postal questionnaire was constructed with questions on occupational and family circumstances, and sent to 513 randomly selected female white-collar workers, of whom 233 had ongoing sick-leave of 90 days or more. The response rate was 81% (n = 413). Most of the women in this study were in managerial positions. The unadjusted associations showed that sick-listed women with children showed the highest estimates regarding reported long working hours, bullying, high mental strain, low control and low influence at work, and work-family imbalance. In a regression model, the strongest associations were: experiencing too high mental strain in work tasks (odds ratio (OR) = 2.57, 95% confidence interval (CI) = 2.09-3.15) and low control and influence at work (OR=2.17, 95% CI= 1.60-2.94). Sick-listed women reported an overall higher dissatisfaction with their workplace and working life. There seems to be a greater tendency for the sick-listed women in this study to experience low control and too high mental strain at work and to live in traditional family relationships with unequal opportunities. The women who were sick-listed were probably less able to cope with work stress and to find a balance between work and family life.

  8. [Assistance and care of the sick in early Christianity].

    Science.gov (United States)

    Maritano, Mario

    2012-01-01

    Christianity presents a new vision of man (personalistic anthropology) and refers to the example and words of Jesus, highlighting the inseparable relationship between the love of God and the love of man. The article describes the assistance and care of the sick in the East and West in the early Christian centuries; the 'places of care'- nosokomia for the sicks, gerontokomia for the olders, brephotropia for abandoned children, orphanage structures; the managers of hospitals, ecclesistical dignitaries, lay personnel, monks, operators and employees. Christianity gave dignity to the sick and opportunity to serve humanity to the healthy.

  9. Psychosocial work conditions associated with sickness absence among hospital employees

    DEFF Research Database (Denmark)

    Suadicani, P; Olesen, K; Bonde, J P

    2014-01-01

    's salary database. RESULTS: A total of 1809 hospital employees took part with a response rate of 65%. The mean age was 43 (range: 20-69) and 75% were female. Totally, 363 study participants (20%) had at least 14 days sickness absence (defined as high absence) during the preceding year. Associations between...... essential covariates of sickness absence. METHODS: A cross-sectional questionnaire study of hospital employees which sought information on elements of the psychosocial work environment, general health status, life style, age, gender and profession. Data on sickness absence were obtained from the employer...

  10. Age differences in the association between stressful work and sickness absence among full-time employed workers: evidence from the German socio-economic panel.

    Science.gov (United States)

    Götz, Simon; Hoven, Hanno; Müller, Andreas; Dragano, Nico; Wahrendorf, Morten

    2018-05-01

    We aim to extend current knowledge on associations between stressful work and sickness absence, first, by studying associations between ERI and sickness absence among full-time employees from various occupations, and second, by investigating if associations vary by age. We use data from four waves of the German socio-economic panel (GSOEP), collected among men and women between 2006 and 2012, with 9418 observations. Stressful work is measured with a short form of the ERI questionnaire. We investigate an imbalance between effort and reward (ER ratio) as well as the two main components ("high effort" and "low reward"). Sickness absence is measured by self-reported number of sickness days (assessed the following year). After descriptive analyses, we estimate a series of multivariable regressions, including tests for interactions between age and work stress. Each of the three indicators of stressful work is related to higher number of sickness days, with except of "high effort" in case of men. Findings remain significant after adjusting for social position (income, education and occupational class) and health. In addition, for both men and women, associations were slightly higher among older workers, though interactions did not reach statistical significance. Our findings support that stressful work is linked to sickness absence across a wide spectrum of jobs with varying incomes and educational levels, and also that associations are slightly more pronounced among older workers.

  11. Encounters between workers sick-listed with common mental disorders and return-to-work stakeholders. Does workers' gender matter?

    NARCIS (Netherlands)

    Nielsen, Maj Britt D.; Madsen, Ida E. H.; Bultmann, Ute; Christensen, Ulla; Diderichsen, Finn; Rugulies, Reiner

    Introduction: The aims of this paper were to examine how disabled workers assess encounters with return-to-work (RTW) stakeholders during sickness absence due to common mental disorders (CMD) and to investigate gender differences in these assessments. Method: Data on contact with and assessment of

  12. External Validation and Update of a Prediction Rule for the Duration of Sickness Absence Due to Common Mental Disorders

    NARCIS (Netherlands)

    Norder, Giny; Roelen, Corne A. M.; van der Klink, Jac J. L.; Bultmann, Ute; Sluiter, J. K.; Nieuwenhuijsen, K.

    Purpose The objective of the present study was to validate an existing prediction rule (including age, education, depressive/anxiety symptoms, and recovery expectations) for predictions of the duration of sickness absence due to common mental disorders (CMDs) and investigate the added value of

  13. Long-term sickness absence due to back disorders in crane operators exposed to whole-body vibration

    NARCIS (Netherlands)

    Bongers, P. M.; Boshuizen, H. C.; Hulshof, C. T.; KOEMEESTER, A. P.

    1988-01-01

    In a retrospective (10-year) follow-up study, the incidence of at least one spell of sickness absenteeism of 28 d or longer in crane operators exposed to whole-body vibration and a control group was investigated. In contrast to a previous study on permanent work disability in the same groups, no

  14. Shortened version of the work ability index to identify workers at risk of long-term sickness absence

    NARCIS (Netherlands)

    Schouten, Lianne S.; Bultmann, Ute; Heymans, Martijn W.; Joling, Catelijne I.; Twisk, Jos W. R.; Roelen, Corne A. M.

    2016-01-01

    Background: The Work Ability Index (WAI) identifies non-sicklisted workers at risk of future long-term sickness absence (LTSA). The WAI is a complicated instrument and inconvenient for use in large-scale surveys. We investigated whether shortened versions of the WAI identify non-sicklisted workers

  15. The association between health and sickness absence among Danish and non-Western immigrant cleaners in Denmark

    DEFF Research Database (Denmark)

    Carneiro, Isabella G.; Rasmussen, Charlotte D. N.; Jørgensen, Marie B.

    2013-01-01

    PURPOSE: The aim of the study is to investigate the association between health and sickness absence among Danish and non-Western immigrant cleaners in Denmark. METHODS: This study is based on a cross-sectional analysis of baseline data from 2007 to 2008. The study population includes 276 cleaners...

  16. Linear and nonlinear relations between psychosocial job characteristics, subjective outcomes, and sickness absence : baseline results from SMASH

    NARCIS (Netherlands)

    Jonge, J. de; Houtman, I.L.D.; Bongers, P.M.; Reuvers, M.M.E.N.; Kompier, M.A.J.

    2000-01-01

    This study investigates the demand-control-support (DCS) model by (a) using a more focused measure of job control, (b) testing for interactive and nonlinear relationships, and (c) further extending the model to the prediction of an objective outcome measure (i.e., company-administrated sickness

  17. Cross-National Validation of Prognostic Models Predicting Sickness Absence and the Added Value of Work Environment Variables

    NARCIS (Netherlands)

    Roelen, Corne A. M.; Stapelfeldt, Christina M.; Heymans, Martijn W.; van Rhenen, Willem; Labriola, Merete; Nielsen, Claus V.; Bultmann, Ute; Jensen, Chris

    Purpose To validate Dutch prognostic models including age, self-rated health and prior sickness absence (SA) for ability to predict high SA in Danish eldercare. The added value of work environment variables to the models' risk discrimination was also investigated. Methods 2,562 municipal eldercare

  18. Cross-National Validation of Prognostic Models Predicting Sickness Absence and the Added Value of Work Environment Variables

    NARCIS (Netherlands)

    Roelen, C.A.M.; Stapelfeldt, C.M.; Heijmans, M.W.; van Rhenen, W.; Labriola, M.; Nielsen, C.V.; Bultmann, U.; Jensen, C.

    2015-01-01

    Purpose To validate Dutch prognostic models including age, self-rated health and prior sickness absence (SA) for ability to predict high SA in Danish eldercare. The added value of work environment variables to the models’ risk discrimination was also investigated. Methods 2,562 municipal eldercare

  19. Linear and non-linear relations between psychosocial job characteristics, subjective outcomes, and sickness absence: baseline results from SMASH

    NARCIS (Netherlands)

    Jonge, J. de; Reuvers, M.M.E.N.; Houtman, I.L.D.; Bongers, P.M.; Kompier, M.A.J.

    2000-01-01

    This study investigates the demand-control-support (DCS) model by (a) using a more focused measure of job control, (b) testing for interactive and nonlinear relationships, and (c) further extending the model to the prediction of an objective outcome measure (i.e., company-administrated sickness

  20. Work characteristics and return to work in long-term sick-listed employees with depressive symptoms.

    NARCIS (Netherlands)

    Huijs, J.J.J.M.; Koppes, L.L.J.; Taris, T.W.; Blonk, R.W.B.

    2017-01-01

    Purpose: The present study investigated the relations between work characteristics, depressive symptoms and duration until full return to work (RTW) among long-term sick-listed employees. This knowledge may add to the development of effective interventions and prevention, especially since work

  1. Work characteristics and return to work in long-term sick-listed employees with depressive symptoms

    NARCIS (Netherlands)

    Huijs, Jenny; Koppes, L.L.J.; Taris, A.W.; Blonk, R.W.B.

    2017-01-01

    Purpose The present study investigated the relations between work characteristics, depressive symptoms and duration until full return to work (RTW) among long-term sick-listed employees. This knowledge may add to the development of effective interventions and prevention, especially since work

  2. Work Characteristics and Return to Work in Long-Term Sick-Listed Employees with Depressive Symptoms

    NARCIS (Netherlands)

    Huijs, J.J.J.M.; Koppes, L.L.J.; Taris, T.W.; Blonk, R.WE.B.

    2017-01-01

    Purpose The present study investigated the relations between work characteristics, depressive symptoms and duration until full return to work (RTW) among long-term sick-listed employees. This knowledge may add to the development of effective interventions and prevention, especially since work

  3. Alcohol consumption and risk of unemployment, sickness absence and disability pension in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Maja Baeksgaard; Thygesen, Lau Caspar; Becker, Ulrik

    2017-01-01

    AIMS: We investigated the association between weekly alcohol consumption and binge drinking and the risk of unemployment, sickness absence and disability pension. DESIGN: Prospective register-based cohort study. SETTING: Denmark. PARTICIPANTS: A sample of 17 690 men and women, aged 18-60 years from...... the Danish Health and Morbidity Survey in 2000, 2005 and 2010 participated in the study. Participants worked the entire year prior to baseline. MEASUREMENTS: Administrative registers were used to obtain information on unemployment, sickness absence and disability pension during a 5-year follow-up period....... Data were analysed by multivariate Cox regression model with random effect (frailty) adjusted for cohabitation status, educational level, Charlson comorbidity index, smoking habits, calendar year and geographic region. FINDINGS: Among males, adjusted hazards ratios (HR) of unemployment were 1.24 (95...

  4. Effects of worksite health interventions involving reduced work hours and physical exercise on sickness absence costs.

    Science.gov (United States)

    von Thiele Schwarz, Ulrica; Hasson, Henna

    2012-05-01

    To investigate the effects of physical exercise during work hours (PE) and reduced work hours (RWH) on direct and indirect costs associated with sickness absence (SA). Sickness absence and related costs at six workplaces, matched and randomized to three conditions (PE, RWH, and referents), were retrieved from company records and/or estimated using salary conversion methods or value-added equations on the basis of interview data. Although SA days decreased in all conditions (PE, 11.4%; RWH, 4.9%; referents, 15.9%), costs were reduced in the PE (22.2%) and RWH (4.9%) conditions but not among referents (10.2% increase). Worksite health interventions may generate savings in SA costs. Costs may not be linear to changes in SA days. Combing the friction method with indirect cost estimates on the basis of value-added productivity may help illuminate both direct and indirect SA costs.

  5. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  6. Effect of organisational change type and frequency on long-term sickness absence in hospitals.

    Science.gov (United States)

    Bernstrøm, Vilde H; Kjekshus, Lars Erik

    2015-09-01

    The present study was conducted to investigate how the frequency of structural change and patient care-related change is related to employees' long-term sickness absence. Although a growing body of research is investigating the potentially harmful effects of organisational change on employee health, most studies have focused on single episodes of organisational change and do not differentiate among the types and frequencies of change. National registry data were collected from 2005 and 2007. A total of 34 712 health professionals from 56 hospitals were included (76% nurses, 18% physicians and 6% other health professionals) and the data were analysed using multilevel logistic regression. The research findings reveal a significantly higher probability of long-term sickness absence among employees who experienced more frequent structural changes (OR = 1.03; CI: 1.00-1.06; P changes. A higher frequency of organisational change may lead to more sickness-related absence among employees, with the effect depending on the type of change. These findings highlight the need for managers who are contemplating or are in the process of implementing organisational change to become more aware of the potentially harmful effects of frequent organisational change on employee health. © 2014 John Wiley & Sons Ltd.

  7. Trends of Sickness Certifications in Primary Health Care in Muscat, Sultanate of Oman

    Directory of Open Access Journals (Sweden)

    Faiz A’Rashdy

    2015-03-01

    Full Text Available Objectives: Sickness certification (SC is common practice in primary health care with proven implications on the health system. To assess the rate of sickness certifications in the Bowsher province and describe related demographic, occupational and medical factors. Methods: Our retrospective, cross-sectional study retrieved data for all consultations, with patients aged six to 65 years old, which ended with SC. The data from four primary health care centers in the Bowsher provice were collected during 2011 using the electronic medical record system. Collected data included patient demographics, occupation, date issued, duration of sickness certification, recorded vital signs, and clinical diagnosis. Suitable rates were calculated as percentages and important differences were compared using the chi-square test. Results: The total number of consultation visits for the targeted population was 189,275. Of these 26,096 consultations resulted in SC to a total of 15,758 patients. The overall rate of SC was 13.8 per 100 consultation-years (confidence interval (CI: 13.6–14. SC rates in males were significantly higher than females (17 and 11 per 100 consultations/year, respectively. Patients aged 19–29 years old had the highest rate of SC (18.6/100 consultations/year. School students aged six to 18 years made up 28% of patients, and 24% and 22% of patients were working in the private and public sectors, respectively. No vital signs record was found for 30% of SC visits. The highest rate of SC was in October (17% and the lowest was in August (9%. Acute respiratory infections were the most frequent diagnoses (31% resulting in certifications. The rate of SC issued for Omanis and non-Omanis was 14 and 9 per 100 consultations per year, respectively. Conclusion: Sickness certification is a burden on primary health care in the studied health centers with approximately one in seven consultations ending with SC issued. More investigations are needed to

  8. Trends of sickness certifications in primary health care in muscat, sultanate of oman.

    Science.gov (United States)

    A'Rashdy, Faiz; Al-Hosni, Khamis; Al-Rawahi, Abdulhakeem; Theodorsson, Thord

    2015-03-01

    Sickness certification (SC) is common practice in primary health care with proven implications on the health system. To assess the rate of sickness certifications in the Bowsher province and describe related demographic, occupational and medical factors. Our retrospective, cross-sectional study retrieved data for all consultations, with patients aged six to 65 years old, which ended with SC. The data from four primary health care centers in the Bowsher provice were collected during 2011 using the electronic medical record system. Collected data included patient demographics, occupation, date issued, duration of sickness certification, recorded vital signs, and clinical diagnosis. Suitable rates were calculated as percentages and important differences were compared using the chi-square test. The total number of consultation visits for the targeted population was 189,275. Of these 26,096 consultations resulted in SC to a total of 15,758 patients. The overall rate of SC was 13.8 per 100 consultation-years (confidence interval (CI): 13.6-14). SC rates in males were significantly higher than females (17 and 11 per 100 consultations/year, respectively). Patients aged 19-29 years old had the highest rate of SC (18.6/100 consultations/year). School students aged six to 18 years made up 28% of patients, and 24% and 22% of patients were working in the private and public sectors, respectively. No vital signs record was found for 30% of SC visits. The highest rate of SC was in October (17%) and the lowest was in August (9%). Acute respiratory infections were the most frequent diagnoses (31%) resulting in certifications. The rate of SC issued for Omanis and non-Omanis was 14 and 9 per 100 consultations per year, respectively. Sickness certification is a burden on primary health care in the studied health centers with approximately one in seven consultations ending with SC issued. More investigations are needed to identify determinates of high sickness absence. Robust guidelines

  9. Undetected common mental disorders in long-term sickness absence

    DEFF Research Database (Denmark)

    Søgaard, Hans Jørgen

    2012-01-01

    Background. Undetected Common Mental Disorders (CMDs) amongst people on sick leave complicate rehabilitation and return to work because appropriate treatments are not initiated. Aims. The aim of this study is to estimate (1) the frequencies of CMD, (2) the predictors of undetected CMD, and (3...... individuals registered on LSA who were sick-listed without a psychiatric sick leave diagnosis. In this respect, Phase 1 included 831 individuals, who were screened for mental disorders. In Phase 2, following the screening of Phase 1, 227 individuals were thoroughly examined by a psychiatrist applying Present...... State Examination. The analyses of the study were carried out based on the 227 individuals from Phase 2 and, subsequently, weighted to be representative of the 831 individuals in Phase 1. Results. The frequencies of undetected mental disorders among all sick-listed individuals were for any psychiatric...

  10. Braid My Hair - Randy Owen sings out for sick children

    Science.gov (United States)

    ... Issue Past Issues Braid My Hair - Randy Owen sings out for sick children Past Issues / Spring 2008 ... to it. Former Alabama lead singer Randy Owen sings his new song, "Braid My Hair." Photo courtesy ...

  11. Gut Feelings About Gastritis: When Your Stomach's Sick

    Science.gov (United States)

    ... November 2012 Print this issue Gut Feelings About Gastritis When Your Stomach’s Sick Send us your comments ... protective response to injury or infection. is called gastritis, and it can cause long-term problems. Some ...

  12. Sickness absence, moral hazard, and the business cycle.

    Science.gov (United States)

    Pichler, Stefan

    2015-06-01

    The procyclical nature of sickness absence has been documented by many scholars in literature. So far, explanations have been based on labor force composition and reduced moral hazard caused by fear of job loss during recessions. In this paper, we propose and test a third mechanism caused by reduced moral hazard during booms and infections. We suggest that the workload is higher during economic booms and thus employees have to go to work despite being sick. In a theoretical model focusing on infectious diseases, we show that this will provoke infections of coworkers leading to overall higher sickness absence during economic upturns. Using state-level aggregated data from 112 German public health insurance funds (out of 145 in total), we find that sickness absence due to infectious diseases shows the largest procyclical pattern, as predicted by our theoretical model. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Identifying risk factors that contribute to acute mountain sickness

    African Journals Online (AJOL)

    Acute mountain sickness (AMS) is an ever-increasing burden on the health sector. With reported incidences .... schedule to reduce the likelihood of AMS. The data ... of Health and. Multidisciplinary Board on Exercise to identify individuals who.

  14. Explanation of nurse standard of external exposure acute radiation sickness

    International Nuclear Information System (INIS)

    Lu Xiuling; Jiang Enhai; Sun Feifei; Zhang Bin; Wang Xiaoguang; Wang Guilin

    2012-01-01

    National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

  15. Work Characteristics and Return to Work in Long-Term Sick-Listed Employees with Depressive Symptoms.

    Science.gov (United States)

    Huijs, Jenny J J M; Koppes, Lando L J; Taris, Toon W; Blonk, Roland W B

    2017-12-01

    Purpose The present study investigated the relations between work characteristics, depressive symptoms and duration until full return to work (RTW) among long-term sick-listed employees. This knowledge may add to the development of effective interventions and prevention, especially since work characteristics can be subjected to interventions more easily than many disorder-related or personal factors. Methods this prospective cohort study with a two-year follow-up employs a sample of 883 Dutch employees who had been sick-listed for at least 13 weeks at baseline, who filled out three questionnaires: at 19 weeks, 1 and 2 years after the start of sick leave. The dependent measure was duration until full RTW. Results not working (partially) at baseline, low decision authority, high psychological demands, low supervisor support and low RTW self-efficacy were related to more depressive symptoms. The duration until full RTW was longer for employees with depressive symptoms. Low physical exertion, high RTW self-efficacy, working partially at baseline, being married or cohabiting, and young age were related to less time until full RTW. Other work characteristics appeared no independent predictors of RTW. Conclusions although the role of job demands and job resources in the RTW process is limited for long-term sick-listed employees with depressive symptoms, a few work characteristics are prognostic factors of full RTW. Focus on these elements in the selection or development of interventions may be helpful in preventing sickness absence, and in supporting long-term sick-listed employees towards full RTW.

  16. You’re the Flight Surgeon: Pulmonary Decompression Sickness

    Science.gov (United States)

    2008-06-01

    follow-up of this patient Diagnosis: Decompression sickness (DeS) with pulmonary symptoms (Type Il DeS, older nomenclature). Treatment: Hyperbaric ...is quite clear thai any case of suspected decompression sickness in the USAF be discussed with the hyperbariC medicine specialists at Brooks City...physician in as respectful manner as you can that you suspect the patient’s condition is likely related to his hypobaric exposure. B. Agree with

  17. Worried sick? Worker Responses to a Financial Shock

    OpenAIRE

    Bratberg, Espen; Monstad, Karin

    2013-01-01

    Excessive sickness absence may hurt productivity and put a strain on public finances. One explanation put forward for increasing absence rates is that a tougher labour market represents a health hazard. A competing hypothesis is that loss of job security works as a disciplinary device. We use a financial shock that hit the public sector in Norway in 2007 in some, but not all, municipalities to identify the effect of reduced job security on sickness absence. Public sector workers i...

  18. Systematic review of active workplace interventions to reduce sickness absence

    OpenAIRE

    Odeen, Magnus; Magnussen, Liv Heide; Mæland, Silje; Larun, Lillebeth; Eriksen, Hege Randi; Tveito, Torill Helene

    2013-01-01

    Background: The workplace is used as a setting for interventions to prevent and reduce sickness absence, regardless of the specific medical conditions and diagnoses. Aims: To give an overview of the general effectiveness of active workplace interventions aimed at preventing and reducing sickness absence. Methods: We systematically searched PubMed, Embase, Psych-info, and ISI web of knowledge on 27 December 2011. Inclusion criteria were (i) participants over 18 years old with ...

  19. Decompression sickness in breath-hold divers: a review.

    Science.gov (United States)

    Lemaitre, Frederic; Fahlman, Andreas; Gardette, Bernard; Kohshi, Kiyotaka

    2009-12-01

    Although it has been generally assumed that the risk of decompression sickness is virtually zero during a single breath-hold dive in humans, repeated dives may result in a cumulative increase in the tissue and blood nitrogen tension. Many species of marine mammals perform extensive foraging bouts with deep and long dives interspersed by a short surface interval, and some human divers regularly perform repeated dives to 30-40 m or a single dive to more than 200 m, all of which may result in nitrogen concentrations that elicit symptoms of decompression sickness. Neurological problems have been reported in humans after single or repeated dives and recent necropsy reports in stranded marine mammals were suggestive of decompression sickness-like symptoms. Modelling attempts have suggested that marine mammals may live permanently with elevated nitrogen concentrations and may be at risk when altering their dive behaviour. In humans, non-pathogenic bubbles have been recorded and symptoms of decompression sickness have been reported after repeated dives to modest depths. The mechanisms implicated in these accidents indicate that repeated breath-hold dives with short surface intervals are factors that predispose to decompression sickness. During deep diving, the effect of pulmonary shunts and/or lung collapse may play a major role in reducing the incidence of decompression sickness in humans and marine mammals.

  20. The actions of the social insurance agency regarding long-term sickness absentees before and after a medical assessment--a study of 384 case files.

    Science.gov (United States)

    Marklund, Staffan; Lundh, Göran; Gustafsson, Klas; Linder, Jürgen; Svedberg, Pia; Alexanderson, Kristina

    2015-01-01

    The purpose of this article is to investigate actions taken by the Social Insurance Agency (SIA) for long-term sickness absentees and possible associations of this with future sick leave or disability pension. For 384 long-term sickness absentees who had had a multidisciplinary medical assessment (MMA) during 2001-2006, three types of data were obtained: (1) case file information about SIA actions, (2) suggested rehabilitation measures from the MMA and (3) sickness absence and disability pension data. Most individuals had been subject to a range of actions by the SIA. Sixty percent had been invited to a coordination meeting, and half of those who assessed by the MMA for vocational rehabilitation were approved to get it by the SIA. Few SIA actions were associated with full or partial return to work. Although the studied individuals had been on sick leave for a long time, the number of SIA actions related to vocational rehabilitation was limited and came late in the sick-leave spell. The information from the MMA was often not used as a basis for further SIA action and seldom resulted in return to work. The positive MMA views on the potential of vocational rehabilitation were not met by SIA actions. Suggestions on vocational rehabilitation from a medical assessment was in many cases not used by the social insurance agency in relationship to long-term sickness absentees. Active rehabilitation measures by the social insurance agency were few and came late in the sickness absence process. Few of the activities taken by the social insurance agency enhanced return to work.