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Sample records for effective work function

  1. Strain effects on the work function of an organic semiconductor

    KAUST Repository

    Wu, Yanfei

    2016-02-01

    Establishing fundamental relationships between strain and work function (WF) in organic semiconductors is important not only for understanding electrical properties of organic thin films, which are subject to both intrinsic and extrinsic strains, but also for developing flexible electronic devices. Here we investigate tensile and compressive strain effects on the WF of rubrene single crystals. Mechanical strain induced by thermal expansion mismatch between the substrate and rubrene is quantified by X-ray diffraction. The corresponding WF change is measured by scanning Kelvin probe microscopy. The WF of rubrene increases (decreases) significantly with in-plane tensile (compressive) strain, which agrees qualitatively with density functional theory calculations. An elastic-to-plastic transition, characterized by a steep rise of the WF, occurs at ~0.05% tensile strain along the rubrene π-stacking direction. The results provide the first concrete link between mechanical strain and WF of an organic semiconductor and have important implications for understanding the connection between structural and electronic disorder in soft organic electronic materials.

  2. Effects of ¿9-Tetrahydrocannabinol on human working memory function

    NARCIS (Netherlands)

    Bossong, M.G.; Jansma, J.M.; Hell, van H.H.; Jager, G.; Oudman, E.; Saliasi, E.; Kahn, R.S.; Ramsey, N.F.

    2012-01-01

    Background Evidence indicates involvement of the endocannabinoid (eCB) system in both the pathophysiology of schizophrenia and working memory (WM) function. Additionally, schizophrenia patients exhibit relatively strong WM deficits. These findings suggest the possibility that the eCB system is also

  3. Work function engineering of graphene oxide via covalent functionalization for organic field-effect transistors

    Science.gov (United States)

    Ji, Seulki; Min, Bok Ki; Kim, Seong K.; Myung, Sung; Kang, Minseo; Shin, Hong-Suk; Song, Wooseok; Heo, Jungseok; Lim, Jongsun; An, Ki-Seok; Lee, Ill-Young; Lee, Sun Sook

    2017-10-01

    We report a simple method to produce work-function-tuned graphene nanosheets based on the nucleophilic substitution of the epoxy groups on graphene oxide. The electrical property of the graphene oxide is controlled dramatically, which results in the apparent work functions in a broad range between 3.73 eV and 5.1 eV, by attaching various functional groups on the graphene surface. As a proof of concept, we successfully demonstrated organic field effect transistors incorporating the functionalized graphene nanosheet interlayers. Here, when nanosheets were applied in an organic transistor as the interlayer material between electrodes and organic channel, the device performance was significantly improved. Our approach can be utilized to increase the performance and the flexibility of various advanced carbon-material-based hybrid electrical devices.

  4. The effect of remission status on work functioning in employed patients treated for major depressive disorder.

    Science.gov (United States)

    Sarfati, David; Stewart, Kurtis; Woo, Cindy; Parikh, Sagar V; Yatham, Lakshmi N; Lam, Raymond W

    2017-02-01

    The ability to function at work is impaired in patients with major depressive disorder (MDD) but few clinical trials include occupational outcome assessments. This study examined whether symptom remission following treatment for MDD is associated with work functioning improvement. We conducted a secondary analysis of a 12-week randomized clinical trial comparing escitalopram with or without telephone-administered cognitive therapy in employed patients with MDD (N = 86). Outcomes included the Montgomery-Åsberg Depression Rating Scale (MADRS) and validated, self-rated work functioning scales including the Lam Employment Absence and Productivity Scale (LEAPS), Work Performance Questionnaire (HPQ), and Sheehan Disability Scale (SDS). Remission was defined as MADRS score ≤10 at 12 weeks. Data were evaluated using analysis of covariance with baseline score as covariates. Remission status was associated with significant improvement in work performance as assessed by the LEAPS productivity subscale, HPQ overall performance, and the SDS work/school item; a trend (P = .08) was observed with the HPQ productivity subscale. The effect sizes (d = 0.23, 0.51, 0.36, and 0.43, respectively) indicate small to medium effects that are likely clinically significant. The results of our study confirm that symptom remission following treatment is associated significantly with improvement in work performance and productivity, as measured by validated work functioning scales. Measurement-based care for MDD should include both symptom and functional outcome assessments.

  5. Effects of Marital Status and Shift Work on Family Function among Registered Nurses

    Science.gov (United States)

    TAI, Shu-Yu; LIN, Pei-Chen; CHEN, Yao-Mei; HUNG, Hsin-Chia; PAN, Chih-Hong; PAN, Shung-Mei; LEE, Chung-Yin; HUANG, Chia-Tsuan; WU, Ming-Tsang

    2014-01-01

    This study aims to assess the interactive effect of marital status and shift work on family function. A population-based sample of 1,438 nurses between the ages of 20–45 yr was recruited from Taiwan during the period from July 2005 to April 2006 using a mailed questionnaire. The self-administered questionnaire contained information about demographic data, work status, shift work schedule, and the Family APGAR (Adaptation, Partnership, Growth, Affection, and Resolve) Scale, to evaluate family function. Compared to day shift nurses, non-night and rotation shift nurses had 1.53- and 1.38-fold (95% CI=1.09–2.14 and 1.01–1.88) risk to have poor family function after adjusting for other covariates. Married nurses, by contrast, had a 0.44-fold (95% CI=0.29–0.66) risk to have poor family function compared to single nurses. In addition, married nurses who worked non-night or rotation shifts had a significantly higher percent of poor family function than those married nurses working day shifts; however, similar results were not replicated in single nurses. We concluded that shift work and marital status could influence family function. PMID:24909112

  6. Strain Effect on Electronic Structure and Work Function in α-Fe2O3 Films

    Directory of Open Access Journals (Sweden)

    Li Chen

    2017-03-01

    Full Text Available We investigate the electronic structure and work function modulation of α-Fe2O3 films by strain based on the density functional method. We find that the band gap of clean α-Fe2O3 films is a function of the strain and is influenced significantly by the element termination on the surface. The px and py orbitals keep close to Fermi level and account for a pronounced narrowing band gap under compressive strain, while unoccupied dz2 orbitals from conduction band minimum draw nearer to Fermi level and are responsible for the pronounced narrowing band gap under tensile strain. The spin polarized surface state, arising from localized dangling-bond states, is insensitive to strain, while the bulk band, especially for pz orbital, arising from extended Bloch states, is very sensitive to strain, which plays an important role for work function decreasing (increasing under compressive (tensile strain in Fe termination films. In particular, the work function in O terminated films is insensitive to strain because pz orbitals are less sensitive to strain than that of Fe termination films. Our findings confirm that the strain is an effective means to manipulate electronic structures and corrosion potential.

  7. Strain Effect on Electronic Structure and Work Function in α-Fe2O3 Films

    Science.gov (United States)

    Chen, Li; Shi, Changmin; Li, Xiaolong; Mi, Zhishan; Wang, Dongchao; Liu, Hongmei; Qiao, Lijie

    2017-01-01

    We investigate the electronic structure and work function modulation of α-Fe2O3 films by strain based on the density functional method. We find that the band gap of clean α-Fe2O3 films is a function of the strain and is influenced significantly by the element termination on the surface. The px and py orbitals keep close to Fermi level and account for a pronounced narrowing band gap under compressive strain, while unoccupied dz2 orbitals from conduction band minimum draw nearer to Fermi level and are responsible for the pronounced narrowing band gap under tensile strain. The spin polarized surface state, arising from localized dangling-bond states, is insensitive to strain, while the bulk band, especially for pz orbital, arising from extended Bloch states, is very sensitive to strain, which plays an important role for work function decreasing (increasing) under compressive (tensile) strain in Fe termination films. In particular, the work function in O terminated films is insensitive to strain because pz orbitals are less sensitive to strain than that of Fe termination films. Our findings confirm that the strain is an effective means to manipulate electronic structures and corrosion potential. PMID:28772631

  8. Effect of shift work on endothelial function in young cardiology trainees.

    Science.gov (United States)

    Tarzia, Pierpaolo; Milo, Maria; Di Franco, Antonino; Di Monaco, Antonio; Cosenza, Alessandro; Laurito, Marianna; Lanza, Gaetano Antonio; Crea, Filippo

    2012-10-01

    Long-term shift work (SW) is associated with an increase in cardiovascular disease (CVD). Previous studies have shown that prolonged SW is associated with endothelial dysfunction, suggesting that this abnormality may contribute to the SW-related increase in cardiovascular risk. The immediate effect of SW on endothelial function in healthy subjects, however, is unknown. We studied endothelial function and endothelium-independent function in 20 healthy specialty trainees in cardiology at our Institute, without any cardiovascular risk factor (27.3 ± 1.9 years, nine males), at two different times: (1) after a working night (WN), and (2) after a restful night (RN). The two test sessions were performed in a random sequence. Endothelial function was assessed by measuring brachial artery dilation during post-ischaemic forearm hyperaemia (flow-mediated dilation, FMD). Endothelium-independent function in response to 25 µg of sublingual glyceryl trinitrate (nitrate-mediated dilation, NMD) was also assessed. FMD was 8.02 ± 1.4% and 8.56 ± 1.7% after WN and RN, respectively (p = 0.025), whereas NMD was 10.5 ± 2.1% and 10.4 ± 2.0% after WN and RN, respectively (p = 0.48). The difference in FMD between WN and RN was not influenced by the numbers of hours slept during WN (4 hours) and by the duration of involvement of specialty trainees in nocturnal work (12 months). Our study shows that in healthy medical residents, without any cardiovascular risk factor, FMD is slightly impaired after WN compared to RN. Disruption of physiological circadian neuro-humoral rhythm is likely to be responsible for this adverse vascular effect.

  9. Effects of bilingualism and aging on executive function and working memory.

    Science.gov (United States)

    Bialystok, Ellen; Poarch, Gregory; Luo, Lin; Craik, Fergus I M

    2014-09-01

    Two studies are reported in which younger and older monolingual and bilingual adults performed executive function tasks. In Study 1, 130 participants performed a Stroop task and bilinguals in both age groups showed less interference than monolinguals with a greater benefit for older adults. In Study 2, 108 participants performed a complex working memory task based on verbal or nonverbal stimuli. Bilinguals showed less interference than monolinguals, with a larger bilingual advantage in the older adult group and in the nonverbal task. Together, these results show that bilingual advantages in executive function depend on characteristics of the participants and features of the tasks, with larger effects found for older than younger adults and for complex tasks using nonverbal material. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  10. Effect of Structure, Temperature, and Metal Work Function on Performance of Organometallic Perovskite Solar Cells

    Science.gov (United States)

    Hossain, M. I.; Aïssa, B.

    2017-03-01

    The impact of hole transport materials (HTMs) on the performance of methylammonium lead halide (CH3NH3PbI3)-based perovskite solar cells has been investigated using computational analysis. The main objective is to replace the HTM with the aim of enhancing the lifetime and decreasing the overall cost of the device. As the CH3NH3PbI3 absorber layer shows an absorption coefficient as high as 105/cm, all photons with incident energy larger the material bandgap are absorbed within only a 400-nm-thick layer. Also, all the electronic and optical properties of such an absorber layer are suitable for use in photovoltaic (PV) devices. Hence, the effects of the HTM thickness, operating temperature, incident light spectrum, and metal electrode work function on the charge collection were studied numerically. For a cell with Cu2O as HTM, efficiency exceeding 25% is predicted for a 350-nm-thick absorber layer. Also, a fully optimized device architecture without HTM shows the possibility of fabricating a perovskite solar cell with PV efficiency exceeding 15%. We expect considerable minimization of the energy loss in this structure due to charge transfer across the heterojunction. Moreover, the effect of temperature on perovskite solar cells and potential electrodes with different work functions has been investigated. Our results are believed to help open an experimental avenue to achieve optimum results for perovskite solar cells with various structures.

  11. Breakfast cereal and caffeinated coffee: effects on working memory, attention, mood, and cardiovascular function.

    Science.gov (United States)

    Smith, A P; Clark, R; Gallagher, J

    1999-08-01

    This study examined the effects of breakfast cereal and caffeinated coffee on working memory, attention, mood, and cardiovascular function. One hundred and forty-four volunteers (72 male, 72 female, mean age 21 years) were assigned to one of the groups formed by combining breakfast (cereal versus no breakfast) and caffeine (caffeinated versus decaffeinated coffee) conditions. The volunteers completed a baseline session between 0800 and 0845 h. The breakfast/caffeine administration took place between 0845 and 0915 h. They then completed another test session (starting at 0945) and had a coffee break at 1045, followed by a final session starting at 1145. The results showed that those who consumed breakfast cereal had a more positive mood at the start of the test sessions, performed better on a spatial memory task, and felt calmer at the end of the test session than those in the no breakfast condition. Ingestion of caffeine had no effect on initial mood or working memory, but it did improve encoding of new information and counteracted the fatigue that developed over the test session. Caffeine increased blood pressure and pulse rate, whereas breakfast cereal consumption only had an effect on pulse. Overall, these results confirm previous findings on the effects of breakfast and caffeine, and demonstrate distinct profiles for two common examples of early-morning food and drink, breakfast cereal and caffeinated coffee.

  12. Effects of gender and executive function on visuospatial working memory in adult obsessive-compulsive disorder.

    Science.gov (United States)

    Martoni, Riccardo Maria; Salgari, Giulia; Galimberti, Elisa; Cavallini, Maria Cristina; O'Neill, Joseph

    2015-12-01

    Visuospatial working memory (VSWM) is the ability of the brain to transiently store and manipulate visual information. VSWM deficiencies have been reported in obsessive-compulsive disorder (OCD), but not consistently, perhaps due to variability in task design and clinical patient factors. To explore this variability, this study assessed effects of the design factors task difficulty and executive organizational strategy and of the clinical factors gender, OCD symptom dimension, and duration of illness on VSWM in OCD. The CANTAB spatial working memory, spatial recognition memory, delayed matching to sample, and stop signal tasks were administered to 42 adult OCD patients and 42 age- and sex-matched healthy controls. Aims were to detect a possible VSWM deficit in the OCD sample, to evaluate influences of the above task and patient factors, to determine the specificity of the deficit to the visuospatial subdomain, and to examine effects of sustained attention as potential neurocognitive confound. We confirmed previous findings of a VSWM deficit in OCD that was more severe for greater memory load (task difficulty) and that was affected by task strategy (executive function). We failed to demonstrate significant deficits in neighboring or confounding neurocognitive subdomains (visual object recognition or visual object short-term memory, sustained attention). Notably, the VSWM deficit was only significant for female patients, adding to evidence for sexual dimorphism in OCD. Again as in prior work, more severe OCD symptoms in the symmetry dimension (but no other dimension) significantly negatively impacted VSWM. Duration of illness had no significant effect on VSWM. VSWM deficits in OCD appear more severe with higher task load and may be mediated through poor task strategy. Such deficits may present mainly in female patients and in (male and female) patients with symmetry symptoms.

  13. Effect on work ability after team evaluation of functioning regarding pain, self-rated disability, and work ability assessment.

    Science.gov (United States)

    Norrefalk, Jan-Rickard; Littwold-Pöljö, Agneta; Ryhle, Leif; Jansen, Gunilla Brodda

    2010-08-26

    To evaluate the effect of a 1-2 week multiprofessional team assessment, without a real rehabilitation effort, 60 patients suffering from long-standing pain and on long-lasting time on sick leave were studied. A questionnaire concerning their daily activities, quality of life, pain intensity, sick-leave level, and their work state was filled out by all patients before starting the assessment and at a 1-year follow-up. The results from the assessment period and the multiprofessional team decision of the patient's working ability were compared with the actual working rate after 1 year. The follow-up showed a significant reduction of sick leave and a higher level of activity (P work. However, the team evaluation of the patient's work ability did not correlate to predict the actual outcome. The patient's pain intensity, life satisfaction, gender, age, ethnic background, and time absent from work before the start of the evaluation showed no correlation to reduction on time on sickness benefit level. These parameters could not be used as predictors in this study.

  14. The effects of desvenlafaxine on neurocognitive and work functioning in employed outpatients with major depressive disorder.

    Science.gov (United States)

    Lam, Raymond W; Iverson, Grant L; Evans, Vanessa C; Yatham, Lakshmi N; Stewart, Kurtis; Tam, Edwin M; Axler, Auby; Woo, Cindy

    2016-10-01

    Major depressive disorder (MDD) is associated with staggering personal and economic costs, a major proportion of which stem from impaired psychosocial and occupational functioning. Few studies have examined the impact of depression-related cognitive dysfunction on work functioning. We examined the association between neurocognitive and work functioning in employed patients with MDD. Employed adult outpatients (n=36) with MDD of at least moderate severity (≥23 on the Montgomery Asberg Depression Rating Scale, MADRS) and subjective cognitive complaints completed neurocognitive tests (CNS Vital Signs computerized battery) and validated self-reports of their work functioning (LEAPS, HPQ) before and after 8 weeks of open-label treatment with flexibly-dosed desvenlafaxine 50-100mg/day. Relationships between neurocognitive tests and functional measures were examined using bivariate correlational and multiple regression analyses, as appropriate. An ANCOVA model examined whether significant change in neurocognitive performance, defined as improvement of ≥1SD in the Neurocognition Index (NCI) from baseline to post-treatment, was associated with improved outcomes. Patients showed significant improvements in depressive symptom, neurocognitive, and work functioning measures following treatment with desvenlafaxine (e.g., MADRS response=77% and MADRS remission=49%). There were no significant correlations between changes in NCI or cognitive domain subscales and changes in MADRS, LEAPS, or HPQ scores. However, patients demonstrating significant improvement in NCI scores (n=11, 29%) had significantly greater improvement in clinical and work functioning outcomes compared to those without NCI improvement. The limitations of this study include small sample size, lack of a placebo control group, and lack of a healthy comparison group. Our sample also had more years of education and higher premorbid intelligence than the general population. There were no significant correlations

  15. Effects of combined pharmacotherapy and psychotherapy for improving work functioning in major depressive disorder.

    Science.gov (United States)

    Lam, Raymond W; Parikh, Sagar V; Ramasubbu, Rajamannar; Michalak, Erin E; Tam, Edwin M; Axler, Auby; Yatham, Lakshmi N; Kennedy, Sidney H; Manjunath, Chinnapalli V

    2013-11-01

    Major depressive disorder is associated with significant impairment in occupational functioning and reduced productivity, which represents a large part of the overall burden of depression. To examine symptom-based and work functioning outcomes with combined pharmacotherapy and psychotherapy treatment of major depressive disorder. Employed patients with a DSM-IV diagnosis of major depressive disorder were treated with escitalopram 10-20 mg/day and randomised to: (a) telephone-administered cognitive-behavioural therapy (telephone CBT) (n = 48); or (b) adherence-reminder telephone calls (n = 51). Outcomes included the Montgomery-Åsberg Depression Rating Scale (MADRS), administered by masked evaluators via telephone, and self-rated work functioning scales completed online. (Registered at clinicaltrials.gov: NCT00702598.) After 12 weeks, there were no significant between-group differences in change in MADRS score or in response/remission rates. However, participants in the telephone-CBT group had significantly greater improvement on some measures of work functioning than the escitalopram-alone group. Combined treatment with escitalopram and telephone-administered CBT significantly improved some self-reported work functioning outcomes, but not symptom-based outcomes, compared with escitalopram alone.

  16. The effect of disruption of prefrontal cortical function with transcranial magnetic stimulation on visual working memory

    Directory of Open Access Journals (Sweden)

    Elizabeth S Lorenc

    2015-12-01

    Full Text Available It is proposed that feedback signals from the prefrontal cortex (PFC to extrastriate cortex are essential for goal-directed processing, maintenance, and selection of information in visual working memory (VWM. In a previous study, we found that disruption of PFC function with transcranial magnetic stimulation (TMS in healthy individuals impaired behavioral performance on a face/scene matching task and decreased category-specific tuning in extrastriate cortex as measured with functional magnetic resonance imaging (fMRI. In this study, we investigated the effect of disruption of left inferior frontal gyrus (IFG function on the fidelity of neural representations of two distinct information codes: (1 the stimulus category and (2 the goal-relevance of viewed stimuli. During fMRI scanning, subjects were presented face and scene images in pseudo-random order and instructed to remember either faces or scenes. Within both anatomical and functional regions of interest, a multi-voxel pattern classifier was used to quantitatively assess the fidelity of activity patterns representing stimulus category: whether a face or a scene was presented on each trial, and goal relevance, whether the presented image was task relevant (i.e. a face is relevant in a Remember Faces block, but irrelevant in a Remember Scenes block. We found a reduction in the fidelity of the stimulus category code in visual cortex after left IFG disruption, providing causal evidence that lateral PFC modulates object category codes in visual cortex during VWM. In addition, we found that IFG disruption caused a reduction in the fidelity of the goal relevance code in a distributed set of brain regions. These results suggest that the IFG is involved in determining the task-relevance of visual input and communicating that information to a network of regions involved in further processing during VWM. Finally, we found that participants who exhibited greater fidelity of the goal relevance code in the

  17. Effects of Physical Exercise on Working Memory and Prefrontal Cortex Function in Post-Stroke Patients.

    Science.gov (United States)

    Moriya, M; Aoki, C; Sakatani, K

    2016-01-01

    Physical exercise enhances prefrontal cortex activity and improves working memory performance in healthy older adults, but it is not clear whether this remains the case in post-stroke patients. Therefore, the aim of this study was to examine the acute effect of physical exercise on prefrontal cortex activity in post-stroke patients using near-infrared spectroscopy (NIRS). We studied 11 post-stroke patients. The patients performed Sternberg-type working memory tasks before and after moderate intensity aerobic exercise (40 % of maximal oxygen uptake) with a cycling ergometer for 15 min. We measured the NIRS response at the prefrontal cortex during the working memory task. We evaluated behavioral performance (response time and accuracy) of the working memory task. It was found that physical exercise improved behavioral performance of the working memory task compared with the control condition (p prefrontal cortex activation, particularly in the right prefrontal cortex (p prefrontal cortex activity and improves working memory performance in post-stroke patients.

  18. A preliminary study of the effects of working memory training on brain function.

    Science.gov (United States)

    Stevens, Michael C; Gaynor, Alexandra; Bessette, Katie L; Pearlson, Godfrey D

    2016-06-01

    Working memory (WM) training improves WM ability in Attention-Deficit/Hyperactivity Disorder (ADHD), but its efficacy for non-cognitive ADHD impairments ADHD has been sharply debated. The purpose of this preliminary study was to characterize WM training-related changes in ADHD brain function and see if they were linked to clinical improvement. We examined 18 adolescents diagnosed with DSM-IV Combined-subtype ADHD before and after 25 sessions of WM training using a frequently employed approach (Cogmed™) using a nonverbal Sternberg WM fMRI task, neuropsychological tests, and participant- and parent-reports of ADHD symptom severity and associated functional impairment. Whole brain SPM8 analyses identified ADHD activation deficits compared to 18 non-ADHD control participants, then tested whether impaired ADHD frontoparietal brain activation would increase following WM training. Post hoc tests examined the relationships between neural changes and neurocognitive or clinical improvements. As predicted, WM training increased WM performance, ADHD clinical functioning, and WM-related ADHD brain activity in several frontal, parietal and temporal lobe regions. Increased left inferior frontal sulcus region activity was seen in all Encoding, Maintenance, and Retrieval Sternberg task phases. ADHD symptom severity improvements were most often positively correlated with activation gains in brain regions known to be engaged for WM-related executive processing; improvement of different symptom types had different neural correlates. The responsiveness of both amodal WM frontoparietal circuits and executive process-specific WM brain regions was altered by WM training. The latter might represent a promising, relatively unexplored treatment target for researchers seeking to optimize clinical response in ongoing ADHD WM training development efforts.

  19. Effectiveness of a depression disease management program in improving depression and work function--a pilot study.

    Science.gov (United States)

    Zivin, Kara; Kerber, Kevin; Kuebler, Julie; Jiang, QingMei; Walters, Heather; Klinkman, Michael; McInnis, Melvin; Valenstein, Marcia

    2009-01-01

    We examined whether there were differences in depression and work function outcomes among primary care and specialty mental health patients treated by the Michigan Depression Outreach and Collaborative Care (M-DOCC), a depression care management program, developed by the University of Michigan Depression Center. In addition, we examined the relationship between depressive symptoms and workplace functioning among M-DOCC enrollees over time. We used mixed model and logistic regression analyses. Despite baseline differences in patient characteristics between primary care and specialty care patients, the location of treatment setting was not a significant predictor of depression or work function outcomes over time among patients enrolled in a depression care management program. Patients in both treatment settings showed significant decreases in depressive and functional impairment over time, with improvements in these symptoms occurring concurrently. Patients with greater case severity were less likely to demonstrate depression and work function improvements over time, and more severe side effects were associated with fewer depression symptom improvements over time. Both depression and work function outcomes improved over time among patients enrolled in a depression care management program, and this improvement did not differ based on whether a patient was treated in a primary or specialty care setting.

  20. Mahlburg's Work on Crank Functions

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 3. Mahlburg's Work on Crank Functions - Ramanujan's Partitions Revisited ... Author Affiliations. Nagesh Juluru1 Arni S R Srinivasa Rao1. 5th Floor, PSU, R.A. Fisher Building, Indian Statistical Institute, 203 B.T. Road, Kolkata 700 108, India.

  1. Work Function Engineering of Graphene

    Science.gov (United States)

    Garg, Rajni; Dutta, Naba K.; Roy Choudhury, Namita

    2014-01-01

    Graphene is a two dimensional one atom thick allotrope of carbon that displays unusual crystal structure, electronic characteristics, charge transport behavior, optical clarity, physical & mechanical properties, thermal conductivity and much more that is yet to be discovered. Consequently, it has generated unprecedented excitement in the scientific community; and is of great interest to wide ranging industries including semiconductor, optoelectronics and printed electronics. Graphene is considered to be a next-generation conducting material with a remarkable band-gap structure, and has the potential to replace traditional electrode materials in optoelectronic devices. It has also been identified as one of the most promising materials for post-silicon electronics. For many such applications, modulation of the electrical and optical properties, together with tuning the band gap and the resulting work function of zero band gap graphene are critical in achieving the desired properties and outcome. In understanding the importance, a number of strategies including various functionalization, doping and hybridization have recently been identified and explored to successfully alter the work function of graphene. In this review we primarily highlight the different ways of surface modification, which have been used to specifically modify the band gap of graphene and its work function. This article focuses on the most recent perspectives, current trends and gives some indication of future challenges and possibilities. PMID:28344223

  2. Work Function Engineering of Graphene

    Directory of Open Access Journals (Sweden)

    Rajni Garg

    2014-04-01

    Full Text Available Graphene is a two dimensional one atom thick allotrope of carbon that displays unusual crystal structure, electronic characteristics, charge transport behavior, optical clarity, physical & mechanical properties, thermal conductivity and much more that is yet to be discovered. Consequently, it has generated unprecedented excitement in the scientific community; and is of great interest to wide ranging industries including semiconductor, optoelectronics and printed electronics. Graphene is considered to be a next-generation conducting material with a remarkable band-gap structure, and has the potential to replace traditional electrode materials in optoelectronic devices. It has also been identified as one of the most promising materials for post-silicon electronics. For many such applications, modulation of the electrical and optical properties, together with tuning the band gap and the resulting work function of zero band gap graphene are critical in achieving the desired properties and outcome. In understanding the importance, a number of strategies including various functionalization, doping and hybridization have recently been identified and explored to successfully alter the work function of graphene. In this review we primarily highlight the different ways of surface modification, which have been used to specifically modify the band gap of graphene and its work function. This article focuses on the most recent perspectives, current trends and gives some indication of future challenges and possibilities.

  3. Effects of aging on cerebral oxygenation during working-memory performance: a functional near-infrared spectroscopy study.

    Directory of Open Access Journals (Sweden)

    Anouk Vermeij

    Full Text Available Working memory is sensitive to aging-related decline. Evidence exists that aging is accompanied by a reorganization of the working-memory circuitry, but the underlying neurocognitive mechanisms are unclear. In this study, we examined aging-related changes in prefrontal activation during working-memory performance using functional Near-Infrared Spectroscopy (fNIRS, a noninvasive neuroimaging technique. Seventeen healthy young (21-32 years and 17 healthy older adults (64-81 years performed a verbal working-memory task (n-back. Oxygenated and deoxygenated hemoglobin concentration changes were registered by two fNIRS channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition in older adults, but not in young participants. In both young and older adults, prefrontal activation increased with rising working-memory load. Young adults showed slight right-hemispheric dominance at low levels of working-memory load, while no hemispheric differences were apparent in older adults. Analysis of the time-activation curve during the high working-memory load condition revealed a continuous increase of the hemodynamic response in the young. In contrast to that, a quadratic pattern of activation was found in the older participants. Based on these results it could be hypothesized that young adults were better able to keep the prefrontal cortex recruited over a prolonged period of time. To conclude, already at low levels of working-memory load do older adults recruit both hemispheres, possibly in an attempt to compensate for the observed aging-related decline in performance. Also, our study shows that aging effects on the time course of the hemodynamic response must be taken into account in the interpretation of the results of neuroimaging studies that rely on blood oxygen levels, such as fMRI.

  4. Earthworm Effects without Earthworms: Inoculation of Raw Organic Matter with Worm-Worked Substrates Alters Microbial Community Functioning

    Science.gov (United States)

    Aira, Manuel; Domínguez, Jorge

    2011-01-01

    Background Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc) and indirect effects (i.e. effects derived from earthworm activities such as cast ageing). Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects). Methodology/Principal Findings To address these questions we inoculated fresh organic matter (pig manure) with worm-worked substrates (vermicompost) produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%). We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease). These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects). In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered. Conclusion/Significance Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity. PMID:21298016

  5. Hybrid functional versus quasiparticle calculations for the Schottky barrier and effective work function at TiN/HfO2 interface

    Science.gov (United States)

    Oh, Young Jun; Lee, Alex Taekyung; Noh, Hyeon-Kyun; Chang, K. J.

    2013-02-01

    We investigate the Schottky barrier and effective work function (EWF) at TiN/HfO2 interface through density functional calculations. For different interfaces that consist of either Ti-O or N-Hf interface bonds, the intrinsic metal-induced gap states are nearly independent of the interface structure, with similar decay lengths into the oxide. Due to the weak Fermi-level pinning, the EWF is more sensitive to the extrinsic effect of interface bonding. As N-rich interface bonds are replaced by O-rich bonds, the EWF decreases by up to 0.36 eV, which is attributed to the formation of opposing interface dipoles. To improve the band gap and EWF, we perform both hybrid functional and quasiparticle (QP) calculations. In the GW0 approximation, in which the Green's function is self-consistently calculated by updating only QP energies and the full frequency-dependent dielectric function is used, the agreement of the EWF with experiment is greatly improved, while QP calculations at the G0W0 level or using the plasmon-pole dielectric function tend to overestimate the EWF. In the self-consistent GW approach, in which both QP energies and wave functions are updated in iterations, the band gap is overestimated, resulting in the lower EWF. On the other hand, the EWF is severely underestimated with the hybrid functional because of the larger shift of the valence band edge level of HfO2.

  6. Method of making low work function component

    Science.gov (United States)

    Robinson, Vance [Niskayuna, NY; Weaver, Stanton Earl [Northville, NY; Michael, Joseph Darryl [Delmar, NY

    2011-11-15

    A method for fabricating a component is disclosed. The method includes: providing a member having an effective work function of an initial value, disposing a sacrificial layer on a surface of the member, disposing a first agent within the member to obtain a predetermined concentration of the agent at said surface of the member, annealing the member, and removing the sacrificial layer to expose said surface of the member, wherein said surface has a post-process effective work function that is different from the initial value.

  7. Modafinil for Excessive Sleepiness Associated With Chronic Shift Work Sleep Disorder: Effects on Patient Functioning and Health-Related Quality of Life

    OpenAIRE

    Erman, Milton K.; Rosenberg, Russell; for the U.S. Modafinil Shift Work Sleep Disorder Study Group

    2007-01-01

    Objective: We evaluated the effects of modafinil, a wake-promoting agent, on patient functioning, health-related quality of life, and nighttime and daytime sleep in patients with excessive sleepiness associated with shift work sleep disorder (SWSD).

  8. Experimental and theoretical investigation of the effect of SiO2 content in gate dielectrics on work function shift induced by nanoscale capping layers

    KAUST Repository

    Caraveo-Frescas, J. A.

    2012-09-10

    The impact of SiO2 content in ultrathin gate dielectrics on the magnitude of the effective work function (EWF) shift induced by nanoscale capping layers has been investigated experimentally and theoretically. The magnitude of the effective work function shift for four different capping layers (AlN, Al2O3, La2O3, and Gd2O3) is measured as a function of SiO2 content in the gate dielectric. A nearly linear increase of this shift with SiO2 content is observed for all capping layers. The origin of this dependence is explained using density functional theory simulations.

  9. Identifying potential working mechanisms behind the positive effects of exercise therapy on pain and function in osteoarthritis; a systematic review.

    Science.gov (United States)

    Runhaar, J; Luijsterburg, P; Dekker, J; Bierma-Zeinstra, S M A

    2015-07-01

    Although physical exercise is the commonly recommended for osteoarthritis (OA) patients, the working mechanism behind the positive effects of physical exercise on pain and function is a black box phenomenon. In the present study we aimed to identify possible mediators in the relation between physical exercise and improvements of pain and function in OA patients. A systematic search for all studies evaluating the effects of physical exercise in OA patients and select those that additionally reported the change in any physiological factor from pre-to post-exercise. In total, 94 studies evaluating 112 intervention groups were included. Most included studies evaluated subjects with solely knee OA (96 out of 112 groups). Based on the measured physiological factors within the included studies, 12 categories of possible mediators were formed. Muscle strength and ROM/flexibility were the most measured categories of possible mediators with 61 and 21 intervention groups measuring one or more physiological factors within these categories, respectively. 60% (31 out of 52) of the studies showed a significant increase in knee extensor muscle strength and 71% (22 out of 31) in knee flexor muscle strength over the intervention period. All 5 studies evaluating extension impairments and 10 out of 12 studies (83%) measuring proprioception found a significant change from pre-to post-intervention. An increase of upper leg strength, a decrease of extension impairments and improvement in proprioception were identified as possible mediators in the positive association between physical exercise and OA symptoms. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  10. Effects of surface condition on the work function and valence-band position of ZnSnN2

    Science.gov (United States)

    Shing, Amanda M.; Tolstova, Yulia; Lewis, Nathan S.; Atwater, Harry A.

    2017-12-01

    ZnSnN2 is an emerging wide band gap earth-abundant semiconductor with potential applications in photonic devices such as solar cells, LEDs, and optical sensors. We report the characterization by ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy of reactively radio-frequency sputtered II-IV-nitride ZnSnN2 thin films. For samples transferred in high vacuum, the ZnSnN2 surface work function was 4.0 ± 0.1 eV below the vacuum level, with a valence-band onset of 1.2 ± 0.1 eV below the Fermi level. The resulting band diagram indicates that the degenerate bulk Fermi level position in ZnSnN2 shifts to mid-gap at the surface due to band bending that results from equilibration with delocalized surface states within the gap. Brief (semiconductor against standard redox potentials indicated that ZnSnN2 has an appropriate energy band alignment for use as a photoanode to effect the oxygen-evolution reaction.

  11. A comparison of effectiveness of regulation of working memory function and methylphenidate on remediation of attention deficit hyperactivity disorder (ADHD.

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Mohammadi

    2014-03-01

    Full Text Available Attention Deficit/Hyperactivity Disorder (ADHD is a prevalent and serious disorder affecting such key cognitive components as working memory. Working memory serves to facilitate and check attention in any individual and to focus on those affairs that need to be retained in mind. This study examines whether a combination of the two therapeutic methods of working memory training and Methylphenidate might be more effective in treating ADHD in children aged 6 to 12 years of age than when methylphenidate is applied alone.Subjects of the study are 48 children suffering from ADHD. They were selected by random sampling. The experimental group included 23 children with ADHD who received a combination of working memory training and Methylphenidate, and the control group which included 25 children with ADHD received Methylphenidate only. To check the effects of the intervention, Conners' Parent Rating Scale (CPRS-48 was applied before and after the intervention. After intervention, data were collected from the remaining samples in the two groups. Data were examined both through descriptive statistical methods and analytic statistical methods, including T-student test and Quantile-Quantile Plots diagram.The study demonstrated that a combination of the cognitive intervention of working memory training and methylphenidate is more effective in alleviating ADHD symptoms rather than when methylphenidate is applied in isolation. In the CPRS pre-test and post-test, the mean difference of the experimental and the control group was 8.39 and 1.88 respectively, indicating that the working memory group has improved more than the control group.The study reveals that the ADHD symptoms were more contained in the test group than the control group due to working memory training. The cognitive intervention through working memory training may be effective in alleviating the severity of disorder measured in the pre-test.

  12. Mahlburg's Work on Crank Functions

    Indian Academy of Sciences (India)

    IAS Admin

    jan's work inspired their career in mathematics. 1. Introduction, Background and Motivation. A partition of a positive number n is any non-increasing .... primes less than 33. Mahlburg's outstanding paper im- proved results that were given by Ono [8] to prove the existence of infinite families of partition congruences for.

  13. Long-term effects of psychosocial work stress in midlife on health functioning after labor market exit--results from the GAZEL study.

    Science.gov (United States)

    Wahrendorf, Morten; Sembajwe, Grace; Zins, Marie; Berkman, Lisa; Goldberg, Marcel; Siegrist, Johannes

    2012-07-01

    To study long-term effects of psychosocial work stress in mid-life on health functioning after labor market exit using two established work stress models. In the frame of the prospective French Gazel cohort study, data on psychosocial work stress were assessed using the full questionnaires measuring the demand-control-support model (in 1997 and 1999) and the effort-reward imbalance model (in 1998). In 2007, health functioning was assessed, using the Short Form 36 mental and physical component scores. Multivariate regressions were calculated to predict health functioning in 2007, controlling for age, gender, social position, and baseline self-perceived health. Consistent effects of both work stress models and their single components on mental and physical health functioning during retirement were observed. Effects remained significant after adjustment including baseline self-perceived health. Whereas the predictive power of both work stress models was similar in the case of the physical composite score, in the case of the mental health score, values of model fit were slightly higher for the effort-reward imbalance model (R(2): 0.13) compared with the demand-control model (R²: 0.11). Findings underline the importance of working conditions in midlife not only for health in midlife but also for health functioning after labor market exit.

  14. Effect of baseline cannabis use and working-memory network function on changes in cannabis use in heavy cannabis users: a prospective fMRI study.

    Science.gov (United States)

    Cousijn, Janna; Wiers, Reinout W; Ridderinkhof, K Richard; van den Brink, Wim; Veltman, Dick J; Goudriaan, Anna E

    2014-05-01

    Theoretical models of addiction suggest that a substance use disorder represents an imbalance between hypersensitive motivational processes and deficient regulatory executive functions. Working-memory (a central executive function) may be a powerful predictor of the course of drug use and drug-related problems. Goal of the current functional magnetic resonance imaging study was to assess the predictive power of working-memory network function for future cannabis use and cannabis-related problem severity in heavy cannabis users. Tensor independent component analysis was used to investigate differences in working-memory network function between 32 heavy cannabis users and 41 nonusing controls during an N-back working-memory task. In addition, associations were examined between working-memory network function and cannabis use and problem severity at baseline and at 6-month follow-up. Behavioral performance and working-memory network function did not significantly differ between heavy cannabis users and controls. However, among heavy cannabis users, individual differences in working-memory network response had an independent effect on change in weekly cannabis use 6 months later (ΔR(2) = 0.11, P = 0.006, f(2) = 0.37) beyond baseline cannabis use (ΔR(2) = 0.41) and a behavioral measure of approach bias (ΔR(2) = 0.18): a stronger network response during the N-back task was related to an increase in weekly cannabis use. These findings imply that heavy cannabis users requiring greater effort to accurately complete an N-back working-memory task have a higher probability of escalating cannabis use. Working-memory network function may be a biomarker for the prediction of course and treatment outcome in cannabis users. Copyright © 2013 Wiley Periodicals, Inc.

  15. Effects of vacuum heat treatment on the photoelectric work function and surface morphology of multilayered silver–metal electrical contacts

    Energy Technology Data Exchange (ETDEWEB)

    Akbi, Mohamed, E-mail: akbi_mohamed@umbb.dz [Laboratoire “Arc Electrique et Plasmas Thermiques”, CNRS, UPRES-A 6069, 24, Avenue des Landais, F-63177 Aubière Cedex (France); Department of Physics, Faculty of Sciences, University of Boumerdes (UMBB), Independence Avenue, 35000 Boumerdes (Algeria); Bouchou, Aïssa [Faculty of Physics, University of Algiers (USTHB), B.P. 32, El-Alia, Bab-Ezzouar, 16111 Algiers (Algeria); Zouache, Noureddine [Laboratoire “Arc Electrique et Plasmas Thermiques”, CNRS, UPRES-A 6069, 24, Avenue des Landais, F-63177 Aubière Cedex (France)

    2014-06-01

    Contact materials used for electrical breakers are often made with silver alloys. Mechanical and thermodynamical properties as well as electron emission of such complicated alloys present a lack of reliable and accurate experimental data. This paper deals mainly with electron work function (EWF) measurements about silver–metal (Ag–Me) electrical contacts (Ag–Ni (60/40) and Ag–W (50/50)), before and after surface heat treatments at 513 K–873 K, under UHV conditions (residual gas pressure of 1.4 × 10{sup −7} mbar). The electron work function (EWF) of silver alloyed contacts was measured photoelectrically, using both Fowler's method of isothermal curves and linearized Fowler plots. An interesting fact brought to light by this investigation is that after vacuum heat treatments, the diffusion and/or evaporation phenomena, affecting the atomic composition of the alloy surface, somehow confine the EWF of the silver–nickel alloy, Φ(Ag–Ni), determined at room temperature in interval]Φ(Ag), Φ(Ni) [=] 4.26 eV, 4.51 eV[. Surface analysis of two specimens before and after heating showed a significant increase of tungsten atomic proportion on the contact surface for Ag–W contacts after VH treatments. A multilayer model, taking into account the strong intergranular and volume segregation gives a good interpretation of the obtained results.

  16. Gender-, Race-, and Income-Based Stereotype Threat: The Effects of Multiple Stigmatized Aspects of Identity on Math Performance and Working Memory Function

    Science.gov (United States)

    Tine, Michele; Gotlieb, Rebecca

    2013-01-01

    This study compared the relative impact of gender-, race-, and income-based stereotype threat and examined if individuals with multiple stigmatized aspects of identity experience a larger stereotype threat effect on math performance and working memory function than people with one stigmatized aspect of identity. Seventy-one college students of the…

  17. The Mediating Effects of Work-Related Stress on Mentoring Functions and Job Attitude: A Comparison of General and Special Education Teachers

    Science.gov (United States)

    Rabenhorst, Greg A.

    2011-01-01

    The current study is designed to investigate the mediating effects of work-related stress on the relationship between mentoring functions (i.e., career support, psychosocial support, and role modeling) and measures of job attitude (i.e., job satisfaction and organizational commitment). Mentoring is widely used as a means of assisting in the new…

  18. Work Function and Conductivity of Inkjet-Printed Silver Layers: Effect of Inks and Post-treatments

    Science.gov (United States)

    Mitra, Dana; Mitra, Kalyan Yoti; Dzhagan, Volodymyr; Pillai, Nikhil; Zahn, Dietrich R. T.; Baumann, Reinhard R.

    2017-12-01

    The electronic properties of a printed layer are influenced by a number of factors, including the nature of the ink (nanoparticle- or solution-based), ink composition (solvents, additives, concentration), and post-treatment technologies, especially sintering. One of the major challenges in the field of printed electronics is achieving the desired performance, for example, in terms of conductivity, resistivity, or work function (WF). This work investigates the dependence of sheet resistance and WF on various sintering methodologies. Four different silver nanoparticle inks were inkjet-printed on a flexible polymeric foil and post-treated by thermal sintering (in an oven) or novel sintering processes using infrared or intense pulsed light. The surfaces of the printed and sintered layers were investigated optically, and various inhomogeneities in the layer surface were observed, varying from a smooth to a highly rough appearance with ring-shaped drying structures. An analysis of the sheet resistance revealed notable variation among the various inks and sintering methodologies used. Here, for the very first time, WF is measured and evaluated as a function of sintering methodology and silver ink, and the respective layer formation characteristics realized with the inkjet printing technology. The WF values obtained by ultraviolet photoemission show a similar spread and allow unambiguous trends to be tracked with respect to the type of ink and sintering method used. The values of the WF obtained range from 3.7 eV to 4.3 eV, approaching the reported bulk values of 4.3-4.7 eV. The various silver inks resulted in different WFs when the same sintering method was used, while the same silver ink resulted in different WFs when various sintering methods were applied. Therefore, it is believed that the WF can be tuned over a broad range in a controlled manner to satisfy electronic device requirements.

  19. A preliminary study of the effects of working memory training on brain function in Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Stevens, Michael C.; Gaynor, Alexandra; Bessette, Katie L.; Pearlson, Godfrey D.

    2015-01-01

    Working memory (WM) training improves WM ability in Attention-Deficit/Hyperactivity Disorder (ADHD), but its efficacy for non-cognitive ADHD impairments ADHD has been sharply debated. The purpose of this preliminary study was to characterize WM training-related changes in ADHD brain function and see if they were linked to clinical improvement. We examined 18 adolescents diagnosed with DSM-IV Combined-subtype ADHD before and after 25 sessions of WM training using a frequently employed approach (CogmedTM) using a nonverbal Sternberg WM fMRI task, neuropsychological tests, and participant- and parent-reports of ADHD symptom severity and associated functional impairment. Whole brain SPM8 analyses identified ADHD activation deficits compared to 18 non-ADHD control participants, then tested whether impaired ADHD frontoparietal brain activation would increase following WM training. Post hoc tests examined the relationships between neural changes and neurocognitive or clinical improvements. As predicted, WM training increased WM performance, ADHD clinical functioning, and WM-related ADHD brain activity in several frontal, parietal and temporal lobe regions. Increased left inferior frontal sulcus region activity was seen in all Encoding, Maintenance, and Retrieval Sternberg task phases. ADHD symptom severity improvements were most often positively correlated with activation gains in brain regions known to be engaged for WM-related executive processing; improvement of different symptom types had different neural correlates. The responsiveness of both amodal WM frontoparietal circuits and executive process-specific WM brain regions was altered by WM training. The latter might represent a promising, relatively unexplored treatment target for researchers seeking to optimize clinical response in ongoing ADHD WM training development efforts. PMID:26138580

  20. Does cortisol influence core executive functions? A meta-analysis of acute cortisol administration effects on working memory, inhibition, and set-shifting.

    Science.gov (United States)

    Shields, Grant S; Bonner, Joseph C; Moons, Wesley G

    2015-08-01

    The hormone cortisol is often believed to play a pivotal role in the effects of stress on human cognition. This meta-analysis is an attempt to determine the effects of acute cortisol administration on core executive functions. Drawing on both rodent and stress literatures, we hypothesized that acute cortisol administration would impair working memory and set-shifting but enhance inhibition. Additionally, because cortisol is thought to exert different nongenomic (rapid) and genomic (slow) effects, we further hypothesized that the effects of cortisol would differ as a function of the delay between cortisol administration and cognitive testing. Although the overall analyses were nonsignificant, after separating the rapid, nongenomic effects of cortisol from the slower, genomic effects of cortisol, the rapid effects of cortisol enhanced response inhibition, g+ = 0.113, p=.016, but impaired working memory, g+ = -0.315, p=.008, although these effects reversed over time. Contrary to our hypotheses, there was no effect of cortisol administration on set-shifting. Thus, although we did not find support for the idea that increases in cortisol influence set-shifting, we found that acute increases in cortisol exert differential effects on working memory and inhibition over time. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Effects of cooling and clothing on vertical trajectories of the upper arm and muscle functions during repetitive light work.

    Science.gov (United States)

    Piedrahita, Hugo; Oksa, Juha; Malm, Christer; Sormunen, Erja; Rintamäki, Hannu

    2008-09-01

    The present study was designed to find out if cooling and/or clothing affect the vertical trajectories and muscle function of the upper arm during repetitive light work. Twelve female subjects performed a one-handed lifting task for 60 min while standing in front of a table with six target angles (30 degrees to 220 degrees ). The experiment was carried out in a climatic chamber in three different conditions: at 10 degrees C (C), at 25 degrees C (TN), and at 10 degrees C dressed in cold-protective clothing (C(p)). Skin and rectal temperatures were measured continuously. The vertical trajectories of the head, shoulder, elbow, and wrist on the right side of the body were recorded. Muscular strain (averaged EMG, a-EMG) and EMG gaps in eight muscles on the right upper arm were measured. The variation of the vertical trajectory amplitude of the upper arm measured from the elbow was significantly higher (at 200 degrees ) both at C and C(p) (50 and 25% respectively) and in shoulder (at 220 degrees angle) at C (33%) compared with TN (P muscles studied. In conclusion, in repetitive tasks the high mean vertical trajectory and changes in the amplitude of the trajectory of the upper arm at C and C(p) compared with TN were associated with increased muscular strain and reduced number of EMG gaps (more continuous activation of given muscle fibers). The changes in trajectories may serve as indicator of a risk for local muscle fatigue.

  2. Empowerment as a Function of Contextual Self-Understanding: The Effect of Work Interest Profiling on Career Decision Self-Efficacy and Work Locus of Control

    Science.gov (United States)

    Breeding, R. Richard

    2008-01-01

    Consumer empowerment in rehabilitation counseling has been conceptualized as a function of informed choice and self-determination and has been linked to the concepts of self-efficacy and locus of control, among other variables. Self-understanding in relation to environmental opportunities represents an important underlying component of such…

  3. Ab initio work function of elemental metals

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Rosengaard, N. M.

    1992-01-01

    We have used a recently developed self-consistent Green’s-function technique based on tight-binding linear-muffin-tin-orbital theory to calculate the work function for the close-packed surfaces of 37 elemental metals. The results agree with the limited experimental data obtained from single...

  4. Study on the sweep gas effect on the surface of Li{sub 4}SiO{sub 4} by means of work function measurement

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Atsushi; Yamaguchi, Kenji; Yamawaki, Michio [Tokyo Univ. (Japan)

    1998-03-01

    In the establishment of fuel cycle of tritium, it is important to make research on how the sweep gas composition affects the surface properties of breeder materials and the release of tritium from the surface of them. In this study, the change of contact potential difference (CPD) between Li{sub 4}SiO{sub 4} and Pt was measured in various gas compositions with a high temperature Kelvin probe. The work function change of Li{sub 4}SiO{sub 4} was obtained from the measured CPD and the work function change of Pt which was estimated from blank tests. From the results, the effect of oxygen deficient layer near the surface of Li{sub 4}SiO{sub 4} was observed, and the effect of OH{sup -} at the surface of Li{sub 4}SiO{sub 4} was considered. (author)

  5. Using Functional Near-Infrared Spectroscopy to Measure Effects of Delta 9-Tetrahydrocannabinol on Prefrontal Activity and Working Memory in Cannabis Users

    Directory of Open Access Journals (Sweden)

    Hasan O. Keles

    2017-10-01

    Full Text Available Intoxication from cannabis impairs cognitive performance, in part due to the effects of Δ9-tetrahydrocannabinol (THC, the primary psychoactive compound in cannabis on prefrontal cortex (PFC function. However, a relationship between impairment in cognitive functioning with THC administration and THC-induced change in hemodynamic response has not been demonstrated. We explored the feasibility of using functional near-infrared spectroscopy (fNIRS to examine the functional changes of the human PFC associated with cannabis intoxication and cognitive impairment. Eighteen adult regular cannabis users (final sample, n = 13 performed a working memory task (n-back during fNIRS recordings, before and after receiving a single dose of oral synthetic THC (dronabinol; 20–50 mg. Functional data were collected using a continuous-wave NIRS device, in which 8 Sources and 7 detectors were placed on the forehead, resulting in 20 channels covering PFC regions. Physiological changes and subjective intoxication measures were collected. We found a significant increase in the oxygenated hemoglobin (HbO concentration after THC administration in several channels on the PFC during both the high working memory load (2-back and the low working memory load (0-back condition. The increased HbO response was accompanied by a trend toward an increased number of omission errors after THC administration. The current study suggests that cannabis intoxication is associated with increases in hemodynamic blood flow to the PFC, and that this increase can be detected with fNIRS.

  6. Using Functional Near-Infrared Spectroscopy to Measure Effects of Delta 9-Tetrahydrocannabinol on Prefrontal Activity and Working Memory in Cannabis Users.

    Science.gov (United States)

    Keles, Hasan O; Radoman, Milena; Pachas, Gladys N; Evins, A Eden; Gilman, Jodi M

    2017-01-01

    Intoxication from cannabis impairs cognitive performance, in part due to the effects of Δ9-tetrahydrocannabinol (THC, the primary psychoactive compound in cannabis) on prefrontal cortex (PFC) function. However, a relationship between impairment in cognitive functioning with THC administration and THC-induced change in hemodynamic response has not been demonstrated. We explored the feasibility of using functional near-infrared spectroscopy (fNIRS) to examine the functional changes of the human PFC associated with cannabis intoxication and cognitive impairment. Eighteen adult regular cannabis users (final sample, n = 13) performed a working memory task (n-back) during fNIRS recordings, before and after receiving a single dose of oral synthetic THC (dronabinol; 20-50 mg). Functional data were collected using a continuous-wave NIRS device, in which 8 Sources and 7 detectors were placed on the forehead, resulting in 20 channels covering PFC regions. Physiological changes and subjective intoxication measures were collected. We found a significant increase in the oxygenated hemoglobin (HbO) concentration after THC administration in several channels on the PFC during both the high working memory load (2-back) and the low working memory load (0-back) condition. The increased HbO response was accompanied by a trend toward an increased number of omission errors after THC administration. The current study suggests that cannabis intoxication is associated with increases in hemodynamic blood flow to the PFC, and that this increase can be detected with fNIRS.

  7. Effects of 12-Week Bacopa monnieri Consumption on Attention, Cognitive Processing, Working Memory, and Functions of Both Cholinergic and Monoaminergic Systems in Healthy Elderly Volunteers

    Directory of Open Access Journals (Sweden)

    Tatimah Peth-Nui

    2012-01-01

    Full Text Available At present, the scientific evidence concerning the effect of Bacopa monnieri on brain activity together with working memory is less available. Therefore, we aimed to determine the effect of B. monnieri on attention, cognitive processing, working memory, and cholinergic and monoaminergic functions in healthy elderly. A randomized double-blind placebo-controlled design was utilized. Sixty healthy elderly subjects (mean age 62.62 years; SD 6.46, consisting of 23 males and 37 females, received either a standardized extract of B. monnieri (300 and 600 mg or placebo once daily for 12 weeks. The cholinergic and monoaminergic systems functions were determined using AChE and MAO activities. Working memory was assessed using percent accuracy and reaction time of various memory tests as indices, whereas attention and cognitive processing were assessed using latencies and amplitude of N100 and P300 components of event-related potential. All assessments were performed before treatment, every four weeks throughout study period, and at four weeks after the cessation of intervention. B. monnieri-treated group showed improved working memory together with a decrease in both N100 and P300 latencies. The suppression of plasma AChE activity was also observed. These results suggest that B. monnieri can improve attention, cognitive processing, and working memory partly via the suppression of AChE activity.

  8. Effects of Aging on Cerebral Oxygenation during Working-Memory Performance: A Functional Near-Infrared Spectroscopy Study

    NARCIS (Netherlands)

    Vermeij, A.; Beek, H.E.A. van; Olde Rikkert, M.G.M.; Kessels, R.P.C.

    2012-01-01

    Working memory is sensitive to aging-related decline. Evidence exists that aging is accompanied by a reorganization of the working-memory circuitry, but the underlying neurocognitive mechanisms are unclear. In this study, we examined aging-related changes in prefrontal activation during

  9. Effects of aging on cerebral oxygenation during working-memory performance: a functional near-infrared spectroscopy study

    NARCIS (Netherlands)

    Vermeij, A.; van Beek, A.H.; Olde Rikkert, M.G.M.; Claassen, J.A.H.R.; Kessels, R.P.C.

    2012-01-01

    Working memory is sensitive to aging-related decline. Evidence exists that aging is accompanied by a reorganization of the working-memory circuitry, but the underlying neurocognitive mechanisms are unclear. In this study, we examined aging-related changes in prefrontal activation during

  10. Working Effectively with Interpreters

    Science.gov (United States)

    Cellitti, Anarella

    2010-01-01

    The United States is becoming increasingly diverse, so early childhood educators are often among the first to work with families whose primary languages are other than English. Many parents, guardians, and family members do speak English but not fluently enough to feel comfortable communicating with teachers or administrators. When educators and…

  11. Comparative cost-effectiveness of two interventions to promote work functioning by targeting mental health complaints among nurses: pragmatic cluster randomised trial.

    Science.gov (United States)

    Noben, Cindy; Smit, Filip; Nieuwenhuijsen, Karen; Ketelaar, Sarah; Gärtner, Fania; Boon, Brigitte; Sluiter, Judith; Evers, Silvia

    2014-10-01

    The specific job demands of working in a hospital may place nurses at elevated risk for developing distress, anxiety and depression. Screening followed by referral to early interventions may reduce the incidence of these health problems and promote work functioning. To evaluate the comparative cost-effectiveness of two strategies to promote work functioning among nurses by reducing symptoms of mental health complaints. Three conditions were compared: the control condition consisted of online screening for mental health problems without feedback about the screening results. The occupational physician condition consisted of screening, feedback and referral to the occupational physician for screen-positive nurses. The third condition included screening, feedback, and referral to e-mental health. The study was designed as an economic evaluation alongside a pragmatic cluster randomised controlled trial with randomisation at hospital-ward level. The study included 617 nurses in one academic medical centre in the Netherlands. Treatment response was defined as an improvement on the Nurses Work Functioning Questionnaire of at least 40% between baseline and follow-up. Total per-participant costs encompassed intervention costs, direct medical and non-medical costs, and indirect costs stemming from lost productivity due to absenteeism and presenteeism. All costs were indexed for the year 2011. At 6 months follow-up, significant improvement in work functioning occurred in 20%, 24% and 16% of the participating nurses in the control condition, the occupational physician condition and the e-mental health condition, respectively. In these conditions the total average annualised costs were €1752, €1266 and €1375 per nurse. The median incremental cost-effectiveness ratio for the occupational physician condition versus the control condition was dominant, suggesting cost savings of €5049 per treatment responder. The incremental cost-effectiveness ratio for the e-mental health

  12. Low work function thermionic emission materials

    Energy Technology Data Exchange (ETDEWEB)

    Zavadil, K.R.; King, D.B.; Ruffner, J.A.

    1999-11-01

    Thermionic energy conversion in a microminiature format shows potential as a viable, high efficiency, on-chip power source. Microminiature thermionic converters (MTC) with inter-electrode spacings on the order of microns are currently being prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes than can be integrated into these converters. In this report, the authors demonstrate a method of incorporating thin film emitters into converters using rf sputtering. They find that the resultant films possess a minimum work function of 1.2 eV. Practical energy conversion is hindered by surface work function non-uniformity. They postulate the source of this heterogeneity to be a result of limited bulk and surface transport of barium. Several methods are proposed for maximizing transport, including increased film porosity and the use of metal terminating layers. They demonstrate a novel method for incorporating film porosity based on metal interlayer coalescence.

  13. Effect of Training Focused on Executive Functions (attention, inhibition and working memory in Preschoolers exhibiting ADHD symptoms

    Directory of Open Access Journals (Sweden)

    Anna Maria Re

    2015-08-01

    Full Text Available The development of early intervention strategies for children with symptoms of Attention Deficit Hyperactivity Disorder (ADHD is important because it provides an opportunity to prevent severe problems in the future. The main purpose of this investigation was to determine the efficacy of a group training for the control of attention, working memory and impulsive behaviors, involving five-year-old children with ADHD symptoms. Twenty-six children with ADHD symptoms and 26 with typical development were randomly divided in two conditions. 13 children in each group were assigned to the training condition and the other to the business as usual condition (normal class activity. Children who participated in the intervention showed an improvement in the tasks measuring their control of attention, impulsive behavior and working memory. Moreover, children with typical development who attended the training also improved their competencies. The results confirm the importance of an early intervention for preschool-age children with ADHD symptoms.

  14. Work Function Calculation For Hafnium- Barium System

    Directory of Open Access Journals (Sweden)

    K.A. Tursunmetov

    2015-08-01

    Full Text Available The adsorption process of barium atoms on hafnium is considered. A structural model of the system is presented and on the basis of calculation of interaction between ions dipole system the dependence of the work function on the coating.

  15. Effects of catalpol on mitochondrial function and working memory in mice after lipopolysaccharide-induced acute systemic inflammation.

    Science.gov (United States)

    Zhang, Aihong; Hao, Shuang; Bi, Jing; Bao, Yongming; Zhang, Xiuli; An, Lijia; Jiang, Bo

    2009-09-01

    The aim of this study was to investigate whether catalpol could facilitate recovery from lipopolysaccharide (LPS)-induced cognitive deficits and protect brain mitochondrial function from LPS-induced acute systemic inflammation. In the study, except control group, mice were challenged with a single dose of LPS (100 microg/mouse, i.p.) to mimic an acute peripheral infection. The results showed that LPS enhanced nuclear factor kappa B (NF-kappaB) activation and induced a loss in mitochondrial integrity as shown by a significant decrease in membrane potential and increase in mitochondrial permeability transition pore opening. Pretreatment with catalpol (10 mg/kg d, i.p.) for 10d before injection of LPS reversed the memory deficits induced by LPS, protected brain mitochondrial function, and attenuated LPS-induced NF-kappaB activation. Taken together, these data indicate that catalpol may possess therapeutic potential against LPS-induced acute systemic inflammation by attenuating NF-kappaB activation and protecting mitochondrial function in cerebral cortex and hippocampus.

  16. Work engagement: drivers and effects

    OpenAIRE

    Bakhuys Roozeboom, M.M.C.; Schelvis, R.

    2014-01-01

    The concept of work engagement fits into the tradition of positive psychology, a recent paradigm shift in psychology which focuses on mental health rather than mental illness. This article gives an introduction to the concept of work engagement. Different definitions and viewpoints of the work engagement concept are discussed. This article will discuss the drivers of work engagement, as well as the associated effects that work engagement has on the health and wellbeing of workers and organisa...

  17. The effect of acute moderate psychological stress on working memory-related neural activity is modulated by a genetic variation in catecholaminergic function in humans

    Directory of Open Access Journals (Sweden)

    Shaozheng eQin

    2012-05-01

    Full Text Available Acute stress has an important impact on higher-order cognitive functions supported by the prefrontal cortex (PFC such as working memory (WM. In rodents, such effects are mediated by stress-induced alterations in catecholaminergic signaling, but human data in support of this notion is lacking. A common variation in the gene encoding Catechol-O-methyltransferase (COMT is known to affect basal catecholaminergic availability and PFC functions. Here, we investigated whether this genetic variation (Val158Met modulates effects of stress on WM-related prefrontal activity in humans. In a counterbalanced crossover design, 41 healthy young men underwent functional Magnetic Resonance Imaging (fMRI while performing a numerical N-back WM task embedded in a stressful or neutral context. Moderate psychological stress was induced by a well-controlled procedure involving viewing strongly aversive (versus emotionally neutral movie material in combination with a self-referencing instruction. Acute stress resulted in genotype-dependent effects on WM performance and WM-related activation in the dorsolateral PFC, with a relatively negative impact of stress in COMT Met-homozygotes as opposed to a relatively positive effect in Val-carriers. A parallel interaction was found for WM-related deactivation in the anterior medial temporal lobe. Our findings suggest that individuals with higher baseline catecholaminergic availability (COMT Met-homozygotes appear to reach a supraoptimal state under moderate levels of stress. In contrast, individuals with lower baselines (Val-carriers may reach an optimal state. Thus, our data show that effects of acute stress on higher-order cognitive functions vary depending on catecholaminergic availability at baseline, and thereby corroborate animal models of catecholaminergic signaling that propose a non-linear relationship between catecholaminergic activity and prefrontal functions.

  18. Gate-last TiN/HfO2 band edge effective work functions using low-temperature anneals and selective cladding to control interface composition

    KAUST Repository

    Hinkle, C. L.

    2012-04-09

    Silicon N-metal-oxide-semiconductor (NMOS) and P-metal-oxide-semiconductor (PMOS) band edge effective work functions and the correspondingly low threshold voltages (Vt) are demonstrated using standard fab materials and processes in a gate-last scheme employing low-temperature anneals and selective cladding layers. Al diffusion from the cladding to the TiN/HfO2interface during forming gas anneal together with low O concentration in the TiN enables low NMOS Vt. The use of non-migrating W cladding along with experimentally detected N-induced dipoles, produced by increased oxygen in the TiN, facilitates low PMOS Vt.

  19. Lung function changes in wildland firefighters working at prescribed burns.

    Energy Technology Data Exchange (ETDEWEB)

    Adetona, Olorunfemi; Hall, Daniel, B.; Naeher, L,P.

    2011-10-01

    Although decline in lung function across workshift has been observed in wildland firefighters, measurements have been restricted to days when they worked at fires. Consequently, such results could have been confounded by normal circadian variation associated with lung function. We investigated the across-shift changes in lung function of wildland firefighters, and the effect of cumulative exposure on lung function during the burn season.

  20. Molecular and Cellular Characterization of Space Flight Effects on Microvascular Endothelial Cell Function - PreparatoryWork for the SFEF Project

    Science.gov (United States)

    Balsamo, Michele; Barravecchia, Ivana; Mariotti, Sara; Merenda, Alessandra; De Cesari, Chiara; Vukich, Marco; Angeloni, Debora

    2014-12-01

    Exposure to microgravity during space flight (SF) of variable length induces suffering of the endothelium (the cells lining all blood vessels), mostly responsible for health problems found in astronauts and animals returning from space. Of interest to pre-nosological medicine, the effects of microgravity on astronauts are strikingly similar to the consequences of sedentary life, senescence and degenerative diseases on Earth, although SF effects are accelerated and reversible. Thus, microgravity is a significant novel model for better understanding of common pathologies. A comprehensive cell and molecular biology study is needed in order to explain pathophysiological findings after SFs. This project will study the effects of microgravity and cosmic radiation on endothelial cells (ECs) cultured on the International Space Station through analysis of 1) cell transcriptome, 2) DNA methylome, 3) DNA damage and cell senescence, 4) variations in cell cycle and cell morphology. This project has been selected by the European Space Agency and the Italian Space Agency and is presently in preparation. The ground study presented here was performed to determine the biological and engineering requirements that will allow us to retrieve suitable samples after culturing, fixing and storing ECs in space. We expect to identify molecular pathways activated by space microgravity in microvascular ECs, which may shed light on pathogenic molecular mechanisms responsible for endothelial suffering shared by astronauts and individuals affected with aging, degenerative and sedentary life-associated pathologies on Earth.

  1. [Modeling of functional working state in hypoxia].

    Science.gov (United States)

    Kravchenko, Iu V

    2003-01-01

    The given method automatically allows us to watch functional working states of the brain (FWSB) in dependence on the neurodynamic loading (first-signal positive and brake stimuli). It defines main properties of nervous processes, wave frame of the sensomotor loading (WFSL) at implementation of three following FWSB: hard work of a brain, a prestressful mode with maximal mobilization of forces and stressful mode. It defines a level of function mobility of nervous processes, force of nervous processes, efficiency of a brain, balance of nervous processes by a method of the parametrical spectral analysis WFSL. The given model allows defining a level of men training who operate in extreme conditions of information processing and hypoxia.

  2. Hearing aid noise suppression and working memory function

    DEFF Research Database (Denmark)

    Neher, Tobias; Wagener, Kirsten C.; Fischer, Rosa-Linde

    2017-01-01

    OBJECTIVE: Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading...

  3. Cross-sectional study on respiratory effect of toner-exposed work in manufacturing plants, Japan: pulmonary function, blood cells, and biochemical markers.

    Science.gov (United States)

    Kitamura, H; Terunuma, N; Kurosaki, S; Hata, K; Ide, R; Kuga, H; Kakiuchi, N; Masuda, M; Totsuzaki, T; Osato, A; Uchino, B; Kitahara, K; Iwasaki, A; Yoshizumi, K; Morimoto, Y; Kasai, H; Murase, T; Higashi, T

    2009-06-01

    The aim of the study is to examine the relationship between toner-exposed work and health indices related to respiratory disorders and to confirm the baseline of a cohort study to clarify the effect of toner exposure in manufacturing plants. Subjects were 1614 male workers (809 toner-exposed workers and 805 referents) who were engaged in toner manufacturing plants in Japan (Fuji Xerox Co., Ltd). The age of subjects was from 19 to 59 years, and the average age was 40.2 years(median 40 years, SD 7.67). We conducted a pulmonary function test (PEFR, VC, FVC, FEV(1.0)%, V25/Ht) and a blood cell test (RBC, Hb, Hct, Plt, WBC, cell contents of WBC) and measured biochemical indices in blood (ALT, AST, gamma-GTP, CRP, IgE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine. Student t-test and logistic regression analysis were applied to compare between the toner-exposed workers and the referents and to analyze the relationship among indices of effects and independent factors. There was no significant difference between the two groups in blood cell count and biochemical indices. Inflammation- and allergy-related markers such as 8OHdG and IgE also showed no significant difference between toner-exposed workers and the referents. The influence of smoking on pulmonary function indices was observed, but there was no relationship between the pulmonary function and toner-exposed work. In this article, we report a preliminary cross-sectional analysis in the subjects of a cohort study. No difference in pulmonary function indices was observed between the toner-exposed workers and the referents, and there was no consistent relationship between the exposure status and examined indices; however, the prevalence of subjective respiratory symptoms was higher in the exposed workers as presented in another report. Further analysis is important in the ongoing cohort study to clarify the effect of toner exposure on respiratory systems.

  4. Comparative cost-effectiveness of two interventions to promote work functioning by targeting mental health complaints among nurses: pragmatic cluster randomised trial

    NARCIS (Netherlands)

    Noben, Cindy; Smit, Filip; Nieuwenhuijsen, Karen; Ketelaar, Sarah; Gärtner, Fania; Boon, Brigitte; Sluiter, Judith; Evers, Silvia

    2014-01-01

    The specific job demands of working in a hospital may place nurses at elevated risk for developing distress, anxiety and depression. Screening followed by referral to early interventions may reduce the incidence of these health problems and promote work functioning. To evaluate the comparative

  5. Disorder-dissociated effects of fluoxetine on brain function of working memory in attention deficit hyperactivity disorder and autism spectrum disorder.

    Science.gov (United States)

    Chantiluke, K; Barrett, N; Giampietro, V; Brammer, M; Simmons, A; Rubia, K

    2015-04-01

    Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are often co-morbid and share performance and brain dysfunctions during working memory (WM). Serotonin agonists modulate WM and there is evidence of positive behavioural effects in both disorders. We therefore used functional magnetic resonance imaging (fMRI) to investigate shared and disorder-specific brain dysfunctions of WM in these disorders, and the effects of a single dose of the selective serotonin reuptake inhibitor (SSRI) fluoxetine. Age-matched boys with ADHD (n = 17), ASD (n = 17) and controls (n = 22) were compared using fMRI during an N-back WM task. Patients were scanned twice, under either an acute dose of fluoxetine or placebo in a double-blind, placebo-controlled randomized design. Repeated-measures analyses within patients assessed drug effects on performance and brain function. To test for normalization effects of brain dysfunctions, patients under each drug condition were compared to controls. Under placebo, relative to controls, both ADHD and ASD boys shared underactivation in the right dorsolateral prefrontal cortex (DLPFC). Fluoxetine significantly normalized the DLPFC underactivation in ASD relative to controls whereas it increased posterior cingulate cortex (PCC) deactivation in ADHD relative to control boys. Within-patient analyses showed inverse effects of fluoxetine on PCC deactivation, which it enhanced in ADHD and decreased in ASD. The findings show that fluoxetine modulates brain activation during WM in a disorder-specific manner by normalizing task-positive DLPFC dysfunction in ASD boys and enhancing task-negative default mode network (DMN) deactivation in ADHD.

  6. Interfacial oxygen and nitrogen induced dipole formation and vacancy passivation for increased effective work functions in TiN/HfO[sub 2] gate stacks

    KAUST Repository

    Hinkle, C. L.

    2010-03-09

    Effective work function (EWF) changes of TiN/HfO2annealed at low temperatures in different ambient environments are correlated with the atomic concentration of oxygen in the TiN near the metal/dielectric interface. EWF increases of 550 meV are achieved with anneals that incorporate oxygen throughout the TiN with [O]=2.8×1021 cm−3 near the TiN/HfO2interface. However, further increasing the oxygen concentration via more aggressive anneals results in a relative decrease of the EWF and increase in electrical thickness. First-principles calculations indicate the exchange of O and N atoms near the TiN/HfO2interface cause the formation of dipoles that increase the EWF.

  7. Effect of baseline cannabis use and working-memory network function on changes in cannabis use in heavy cannabis users: a prospective fMRI study

    NARCIS (Netherlands)

    Cousijn, Janna; Wiers, Reinout W.; Ridderinkhof, K. Richard; van den Brink, Wim; Veltman, Dick J.; Goudriaan, Anna E.

    2014-01-01

    Theoretical models of addiction suggest that a substance use disorder represents an imbalance between hypersensitive motivational processes and deficient regulatory executive functions. Working-memory (a central executive function) may be a powerful predictor of the course of drug use and

  8. Effect of baseline cannabis use and working-memory network function on changes in cannabis use in heavy cannabis users: A prospective fMRI study

    NARCIS (Netherlands)

    Cousijn, J.; Wiers, R.W.; Ridderinkhof, K.R.; van den Brink, W.; Veltman, D.J.; Goudriaan, A.E.

    2014-01-01

    Theoretical models of addiction suggest that a substance use disorder represents an imbalance between hypersensitive motivational processes and deficient regulatory executive functions. Working-memory (a central executive function) may be a powerful predictor of the course of drug use and

  9. Effect of baseline cannabis use and working-memory network function on changes in cannabis use in heavy cannabis users : a prospective fMRI study

    NARCIS (Netherlands)

    Cousijn, Janna; Wiers, Reinout W; Ridderinkhof, K Richard; van den Brink, Wim; Veltman, Dick J; Goudriaan, Anna E

    2014-01-01

    Theoretical models of addiction suggest that a substance use disorder represents an imbalance between hypersensitive motivational processes and deficient regulatory executive functions. Working-memory (a central executive function) may be a powerful predictor of the course of drug use and

  10. Bike Desks in the Office: Physical Health, Cognitive Function, Work Engagement, and Work Performance.

    Science.gov (United States)

    Torbeyns, Tine; de Geus, Bas; Bailey, Stephen; De Pauw, Kevin; Decroix, Lieselot; Van Cutsem, Jeroen; Meeusen, Romain

    2016-12-01

    The aim of this study was to examine the longitudinal effect of implementing bike desks in an office setting on physical health, cognition, and work parameters. Physical health, cognitive function, work engagement, and work performance measured before (T0) and after (T2) the intervention period were compared between office workers who used the bike desk (IG, n = 22) and those who did not (CG, n = 16). The IG cycled approximately 98 minutes/week. The IG showed a significantly lower fat percentage and a trend toward a higher work engagement at T2 relative to T0, while this was not different for the CG. No effects on other parameters of health, cognition, or work performance were found. Providing bike desks in the office positively influences employees' fat percentage and could positively influence work engagement without compromising work performance.

  11. SYNERGY EFFECTS IN WORK TEAMS

    Directory of Open Access Journals (Sweden)

    Raluca C. ZOLTAN

    2014-06-01

    Full Text Available Today’s organization increasingly utilizes all kind of teams in order to surpass their competitors through flexibility, adaptability and innovation, features which are seen to characterize the teams. For this purpose, the concept of synergy in teams’ activity is often mentioned as the prime reason for which collective work is considered to be superior comparative with individual work. But what exactly does it mean? The present paper aims to shed some light on the concept of synergy in work teams and its positive effects, namely, the social consequences of collective work such as social compensation, social indispensability, social comparison, social identity, but also its negative effects, such as free-riding, social loafing and sucker effect. These are important group phenomena that managers should be aware of because they have a major impact on team performance, and consequently, on organization performance.

  12. Work Criteria Function of Irreversible Heat Engines

    Directory of Open Access Journals (Sweden)

    Mahmoud Huleihil

    2014-01-01

    Full Text Available The irreversible heat engine is reconsidered with a general heat transfer law. Three criteria known in the literature—power, power density, and efficient power—are redefined in terms of the work criteria function (WCF, a concept introduced in this study. The formulation enabled the suggestion and analysis of a unique criterion—the efficient power density (which accounts for the efficiency and power density. Practically speaking, the efficient power and the efficient power density could be defined on any order based on the WCF. The applicability of the WCF is illustrated for the Newtonian heat transfer law (n=1 and for the radiative law (n=4. The importance of WCF is twofold: it gives an explicit design and educational tool to analyze and to display graphically the different criteria side by side and thus helps in design process. Finally, the criteria were compared and some conclusions were drawn.

  13. Improved Work Function of Poly(3,4-ethylenedioxythiophene): Poly(styrenesulfonic acid) and its Effect on Hybrid Silicon/Organic Heterojunction Solar Cells

    Science.gov (United States)

    Shen, Xiaojuan; Chen, Ling; Pan, Jianmei; Hu, Yue; Li, Songjun; Zhao, Jie

    2016-11-01

    Hybrid silicon/organic solar cells have been recently extensively investigated due to their simple structure and low-cost fabrication process. However, the efficiency of the solar cells is greatly limited by the barrier height as well as the carrier recombination at the silicon/organic interface. In this work, hydrochloroplatinic acid (H2PtCl6) is employed into the poly(3,4-ethlenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) solution, and the work function (WF) of the PEDOT:PSS layer has been successfully improved. Based on the Pt-modified PEDOT:PSS layer, the efficiency of the silicon/PEDOT:PSS cell can be increased to 11.46%, corresponding to 20% enhancement to the one without platinum (Pt) modification. Theoretical and experimental results show that, when increasing the WF of the PEDO:PSS layer, the barrier height between the silicon/PEDOT:PSS interface can be effectively enhanced. Meanwhile, the carrier recombination at the interface is significantly reduced. These results can contribute to better understanding of the interfacial mechanism of silicon/PEDOT:PSS interface, and further improving the device performance of silicon/organic solar cells.

  14. Exploring the effect of the apolipoprotein E (APOE) gene on executive function, working memory, and processing speed during the early recovery period following traumatic brain injury.

    Science.gov (United States)

    Padgett, Christine R; Summers, Mathew J; Vickers, James C; McCormack, Graeme H; Skilbeck, Clive E

    2016-01-01

    There is evidence that the e4 allele of the apolipoprotein E (APOE) gene is detrimental to cognitive function, but results from traumatic brain injury (TBI) populations are mixed. A possible explanation is that APOEe2 carriers have routinely been incorporated into APOEe4 and non-e4 groups, despite APOEe2 being proposed to have an ameliorative effect. Our primary aim was to investigate the influence of APOEe4 on cognitive impairment during early recovery following TBI, excluding the potential confound of APOEe2 possession. A secondary objective was to explore whether APOEe4 displays more pronounced effects in moderate to severe TBI and to consider the potential postinjury protective influence of the APOEe2 allele. Participants who recently sustained a TBI (posttraumatic amnesia > 5 minutes) were assessed on measures of information processing speed, executive function, and working memory upon remission of posttraumatic amnesia. APOE genotype was determined by buccal saliva DNA extraction (APOEe4 n = 37, APOEe3 n = 92, APOEe2 n = 13). Stepwise multiple regressions were performed to compare APOEe4 carriers to APOEe3 homozygotes, with injury severity, age, and estimated premorbid IQ included in the first step. This model was found to significantly predict performance on all tasks, accounting for 17.3-24.3% of the variance. When APOEe4 status was added for the second step, there were no significant changes on any tasks (additional variance recovery period following TBI, regardless of injury severity. However, a more nuanced and long-term exploration of the effect of APOE genotype in the TBI population is warranted.

  15. Using Functional Near-Infrared Spectroscopy to Measure Effects of Delta 9-Tetrahydrocannabinol on Prefrontal Activity and Working Memory in Cannabis Users

    OpenAIRE

    Keles, Hasan O.; Radoman, Milena; Pachas, Gladys N.; Evins, A. Eden; Gilman, Jodi M.

    2017-01-01

    Intoxication from cannabis impairs cognitive performance, in part due to the effects of Δ9-tetrahydrocannabinol (THC, the primary psychoactive compound in cannabis) on prefrontal cortex (PFC) function. However, a relationship between impairment in cognitive functioning with THC administration and THC-induced change in hemodynamic response has not been demonstrated. We explored the feasibility of using functional near-infrared spectroscopy (fNIRS) to examine the functional changes of the human...

  16. Effectiveness of Essence of Chicken in Improving Cognitive Function in Young People Under Work-Related Stress: A Randomized Double-Blind Trial.

    Science.gov (United States)

    Chan, Lung; Wang, Hsuan-Min; Chen, Kuan-Yu; Lin, Ying-Chin; Wu, Pei-Jung; Hsieh, Wan-Lin; Chen, Ying-Ru; Liu, Cheung-Pin; Tsai, Han-Yin; Chen, Yun-Ru; Chang, Hsiu-Hui; Hsieh, Yi-Chen; Hu, Chaur-Jong

    2016-05-01

    Work-related stress (WS) can result in considerable and extensive changes in physiological and psychological performance. WS beyond the optimal levels induces anxiety, confusion, exhaustion, and burnout. Chronic WS affects neurocognitive performance, particularly attention and visuospatial memory. Essence of chicken (EC) has been reported to improve neurocognitive function after mental stress.To investigate the beneficial effects of EC in improving neurocognitive performance under WS, we conducted a randomized, double blind trial. Total 102 young workers in New Taipei City with high WS, evaluated using the Individual Subjective Perception Job Stress Scale scores (>36 for job leaders and 33 for nonleaders) were recruited. Fifty-one participants received 70 mL of EC and 51 received a placebo daily for 2 weeks. Blood tests and neurocognitive assessment were performed before treatment, at the end of treatment, and 2 weeks after treatment.EC improved the performance of participants with high depression scores in the form-color associative memory test, used for assessing short-term memory. Although creatinine and glutamic-pyruvic transaminase (GPT) levels increased in week 2, but the levels returned to the baseline in week 4. Blood urea nitrogen (BUN) levels decreased in week 4.EC significantly improved short-term memory in participants with high WS and concomitant depressive mood, although it slightly increased GPT and creatinine levels and reduced BUN levels. The long-term treatment effects of EC warrant further investigation.

  17. Hearing aid noise suppression and working memory function

    DEFF Research Database (Denmark)

    Fischer, Rosa-Linde; Neher, Tobias; Wagener, Kirsten C.

    Research findings concerning the relation between outcome from hearing aid (HA) noise suppression and working memory function are unclear. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory as well as the relation with reading span......) improvement. Auditory working memory was assessed at +6 dB SNR using a listening span and an N-back paradigm. Twenty experienced HA users aged 55-80 yr with large differences in reading span took part. For the listening span measurements, there was an influence of HA setting on final word recognition...

  18. Does improvement of cognitive functioning by cognitive remediation therapy effect work outcomes in severe mental illness? A secondary analysis of a randomized controlled trial.

    Science.gov (United States)

    Ikebuchi, Emi; Sato, Sayaka; Yamaguchi, Sosei; Shimodaira, Michiyo; Taneda, Ayano; Hatsuse, Norifumi; Watanabe, Yukako; Sakata, Masuhiro; Satake, Naoko; Nishio, Masaaki; Ito, Jun-Ichiro

    2017-05-01

    The aim of this study was to clarify whether improvement of cognitive functioning by cognitive remediation therapy can improve work outcome in schizophrenia and other severe mental illnesses when combined with supported employment. The subjects of this study were persons with severe mental illness diagnosed with schizophrenia, major depression, or bipolar disorder (ICD-10) and cognitive dysfunction who participated in both cognitive remediation using the Thinking Skills for Work program and a supported employment program in a multisite, randomized controlled study. Logistic and multiple linear regression analyses were performed to clarify the influence of cognitive functioning on vocational outcomes, adjusting for demographic and clinical variables. Improvement of cognitive functioning with cognitive remediation significantly contributed to the total days employed and total earnings of competitive employment in supported employment service during the study period. Any baseline demographic and clinical variables did not significantly contribute to the work-related outcomes. A cognitive remediation program transferring learning skills into the real world is useful to increase the quality of working life in supported employment services for persons with severe mental illness and cognitive dysfunction who want to work competitively. © 2016 The Authors. Psychiatry and Clinical Neurosciences © 2016 Japanese Society of Psychiatry and Neurology.

  19. Work function engineering using lanthanum oxide interfacial layers

    Science.gov (United States)

    Alshareef, H. N.; Quevedo-Lopez, M.; Wen, H. C.; Harris, R.; Kirsch, P.; Majhi, P.; Lee, B. H.; Jammy, R.; Lichtenwalner, D. J.; Jur, J. S.; Kingon, A. I.

    2006-12-01

    A La2O3 capping scheme has been developed to obtain n-type band-edge metal gates on Hf-based gate dielectrics. The viability of the technique is demonstrated using multiple metal gates that normally show midgap work function when deposited directly on HfSiO. The technique involves depositing a thin interfacial of La2O3 on a Hf-based gate dielectric prior to metal gate deposition. This process preserves the excellent device characteristic of Hf-based dielectrics, but also allows the realization of band-edge metal gates. The effectiveness of the technique is demonstrated by fabricating fully functional transistor devices. A model is proposed to explain the effect of La2O3 capping on metal gate work function.

  20. Nitrogen Gas Flow Ratio and Rapid Thermal Annealing Temperature Dependences of Sputtered Titanium Nitride Gate Work Function and Their Effect on Device Characteristics

    Science.gov (United States)

    Liu, Yongxun; Hayashida, Tetsuro; Matsukawa, Takashi; Endo, Kazuhiko; Masahara, Meishoku; O'uchi, Shinich; Sakamoto, Kunihiro; Ishii, Kenichi; Tsukada, Junichi; Ishikawa, Yuki; Yamauchi, Hiromi; Ogura, Atsushi; Suzuki, Eiichi

    2008-04-01

    A sputtered titanium nitride (TiN) metal gate has systematically been investigated, and the dependences of TiN work function (φTiN) and device performance on nitrogen gas flow ratio [RN=N2/(N2+Ar)] in sputtering and rapid thermal annealing (RTA) temperature (TR) are clarified. It is experimentally found that φTiN slightly decreases from 4.87 to 4.78 eV with increasing RN from 17 to 83%, and it markedly decreases with increasing TR. The analysis of the electrical characteristics of fabricated metal-oxide-semiconductor field-effect transistors (MOSFETs) shows that the optimal RN range is 17-50%, and a higher RN offers a lower Vth owing to the lower φTiN. The origin of φTiN decrease with increasing RN and TR is discussed. The obtained results indicate that φTiN can be controlled by sputtering and RTA conditions, and are very useful for setting the appropriate Vth for lightly doped channel devices such as a FinFET.

  1. Hearing aid noise suppression and working memory function

    DEFF Research Database (Denmark)

    Neher, Tobias; Wagener, Kirsten C.; Fischer, Rosa-Linde

    2018-01-01

    OBJECTIVE: Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading......-to-noise ratio (SNR) improvement. Auditory working memory was assessed at +6 dB SNR using listening span and N-back paradigms. STUDY SAMPLE: Twenty experienced HA users ages 55-80 with large differences in reading span. RESULTS: For the listening span measurements, there was an influence of HA setting....... CONCLUSIONS: HA noise suppression may affect the recognition and recall of speech at positive SNRs, irrespective of individual reading span. Future work should improve the reliability of the auditory working memory measurements....

  2. Work functioning trajectories in cancer patients: Results from the longitudinal Work Life after Cancer (WOLICA) study.

    Science.gov (United States)

    Dorland, Heleen F; Abma, Femke I; Roelen, Corné A M; Stewart, Roy E; Amick, Benjamin C; Ranchor, Adelita V; Bültmann, Ute

    2017-11-01

    More than 60% of cancer patients are able to work after cancer diagnosis. However, little is known about their functioning at work. Therefore, the aims of this study were to (1) identify work functioning trajectories in the year following return to work (RTW) in cancer patients and (2) examine baseline sociodemographic, health-related and work-related variables associated with work functioning trajectories. This longitudinal cohort study included 384 cancer patients who have returned to work after cancer diagnosis. Work functioning was measured at baseline, 3, 6, 9 and 12 months follow-up. Latent class growth modeling (LCGM) was used to identify work functioning trajectories. Associations of baseline variables with work functioning trajectories were examined using univariate and multivariate analyses. LCGM analyses with cancer patients who completed on at least three time points the Work Role Functioning Questionnaire (n = 324) identified three work functioning trajectories: "persistently high" (16% of the sample), "moderate to high" (54%) and "persistently low" work functioning (32%). Cancer patients with persistently high work functioning had less time between diagnosis and RTW and had less often a changed meaning of work, while cancer patients with persistently low work functioning reported more baseline cognitive symptoms compared to cancer patients in the other trajectories. This knowledge has implications for cancer care and guidance of cancer patients at work. © 2017 UICC.

  3. A short executive function training program improves preschoolers’ working memory

    Directory of Open Access Journals (Sweden)

    Emma eBlakey

    2015-11-01

    Full Text Available Cognitive training has been shown to improve executive functions in middle childhood and adulthood. However, fewer studies have targeted the preschool years – a time when executive functions undergo rapid development. The present study tested the effects of a short four session executive function training program in 54 four-year-olds. The training group significantly improved their working memory from pre-training relative to an active control group. Notably, this effect extended to a task sharing few surface features with the trained tasks, and continued to be apparent three months later. In addition, the benefits of training extended to a measure of mathematical reasoning three months later, indicating that training executive functions during the preschool years has the potential to convey benefits that are both long-lasting and wide-ranging.

  4. The annealing effect on work function variation of WN{sub x}C{sub y} films deposited by remote plasma atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyunjung; Shin, Changhee; Lim, Heewoo; Kim, Manseok [Department of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul (Korea, Republic of); Jang, Woochool; Lee, Kunyoung [Division of Materials Science and Engineering, Hanyang University, Seoul (Korea, Republic of); Yuh, Junhan [Division of Steel Solution, POSCO, Seoul (Korea, Republic of); Jeon, Hyeongtag [Department of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul (Korea, Republic of); Division of Materials Science and Engineering, Hanyang University, Seoul (Korea, Republic of)

    2017-07-15

    Tungsten-nitrogen-carbide (WN{sub x}C{sub y}) thin films were investigated as the metal gate of complementary metal-oxide-semiconductor (CMOS) devices. WN{sub x}C{sub y} thin films were deposited by employing the remote plasma atomic layer deposition (RPALD) using a bis(tert-butylimido) bis (dimethylamido) tungsten (BTBMW) precursor and hydrogen plasma as a reactant. The growth rate of the WN{sub x}C{sub y} films was about 0.12 nm/cycle. X-ray diffraction (XRD) analysis indicated that the films consisted of a mixture of tungsten carbide and tungsten nitride phases. The atomic force microscope (AFM) analysis further confirmed that the WN{sub x}C{sub y} film surfaces deposited by RPALD were smooth. In addition, the chemical bonding state analysis showed that the WN{sub x}C{sub y} films consisted of WN, WC, and WO phases. To measure the work function of the WN{sub x}C{sub y} film, a MOSCAP (metal oxide semiconductor capacitor) stack was fabricated and the flat band voltage was measured by current-voltage (C-V) measurements. A WN{sub x}C{sub y} work function value of 4.91 eV was suitable for p-MOS and the work function of the WN{sub x}C{sub y} films varied depending on the annealing treatment, and was higher than the work function of the as-deposited WN{sub x}C{sub y} film. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Work Characteristics Associated with Physical Functioning in Women.

    Science.gov (United States)

    Palumbo, Aimee J; De Roos, Anneclaire J; Cannuscio, Carolyn; Robinson, Lucy; Mossey, Jana; Weitlauf, Julie; Garcia, Lorena; Wallace, Robert; Michael, Yvonne

    2017-04-15

    Women make up almost half of the labor force with older women becoming a growing segment of the population. Work characteristics influence physical functioning and women are at particular risk for physical limitations. However, little research has explored the effects of work characteristics on women's physical functioning. U.S. women between the ages of 50 and 79 were enrolled in the Women's Health Initiative Observational Study between 1993 and 1998. Women provided job titles and years worked at their three longest-held jobs (n = 79,147). Jobs were linked to characteristics in the Occupational Information Network. Three categories of job characteristics related to substantive complexity, physical demand, and social collaboration emerged. The association between job characteristics and physical limitations in later life, measured using a SF-36 Physical Functioning score critical thinking were associated with better physical functioning. Employers should explore opportunities to reduce strain from physically demanding jobs and incorporate substantively complex tasks into women's work to improve long-term health.

  6. Factors Associated with Work Participation and Work Functioning in Depressed Workers : A Systematic Review

    NARCIS (Netherlands)

    Lagerveld, S. E.; Bultmann, U.; Franche, R. L.; van Dijk, F. J. H.; Vlasveld, M. C.; van der Feltz-Cornelis, C. M.; Bruinvels, D. J.; Huijs, J. J. J. M.; Blonk, R. W. B.; van der Klink, J. J. L.; Nieuwenhuijsen, K.

    Background Depression is associated with negative work outcomes such as reduced work participation (WP) (e.g., sick leave duration, work status) and work functioning (WF) (e.g., loss of productivity, work limitations). For the development of evidence-based interventions to improve these work

  7. Work functioning trajectories in cancer patients : Results from the longitudinal Work Life after Cancer (WOLICA) study

    NARCIS (Netherlands)

    Dorland, Heleen F; Abma, Femke I; Roelen, Corné A M; Stewart, Roy E; Amick, Benjamin C; Ranchor, Adelita V; Bültmann, Ute

    2017-01-01

    More than 60% of cancer patients are able to work after cancer diagnosis. However, little is known about their functioning at work. Therefore, the aims of this study were to (1) identify work functioning trajectories in the year following return to work (RTW) in cancer patients and (2) examine

  8. Which Working Memory Functions Predict Intelligence?

    Science.gov (United States)

    Oberauer, Klaus; Sub, Heinz-Martin; Wilhelm, Oliver; Wittmann, Werner W.

    2008-01-01

    Investigates the relationship between three factors of working memory (storage and processing, relational integration, and supervision) and four factors of intelligence (reasoning, speed, memory, and creativity) using structural equation models. Relational integration predicted reasoning ability at least as well as the storage-and-processing…

  9. Simultaneous current-, force- and work function measurement with atomic resolution

    OpenAIRE

    Herz, Markus; Schiller, Christian H.; Giessibl, Franz J.; Mannhart, Jochen

    2005-01-01

    The local work function of a surface determines the spatial decay of the charge density at the Fermi level normal to the surface. Here, we present a method that enables simultaneous measurements of local work function and tip-sample forces. A combined dynamic scanning tunneling microscope and atomic force microscope is used to measure the tunneling current between an oscillating tip and the sample in real time as a function of the cantilever's deflection. Atomically resolved work function mea...

  10. Napping and Human Functioning during Prolonged Work

    Science.gov (United States)

    1987-04-30

    alternative to napping is prolonged wakefulness. Polyphasic sleep , with frequent naps rather than a single sleep period per 24 hours, is natural for both the...very young and for the aged. It is not practiced by most adults, perhaps because of societal demands. Possibly a polyphasic sleep schedule could be...Functioning 1.2 Scope of this Chapter 2. REVIEW OF LITERATURE 2.1 Partial Sleep Deprivation Studies 2.2 Nap Studies: Four Nap Factors Affecting Performance

  11. On the impacts of working memory training on executive functioning

    Directory of Open Access Journals (Sweden)

    Tiina eSalminen

    2012-06-01

    Full Text Available Recent studies have reported improvements in a variety of cognitive functions following sole working memory (WM training. In spite of the emergence of several successful training paradigms, the scope of transfer effects has remained mixed. This is most likely due to the heterogeneity of cognitive functions that have been measured and tasks that have been applied. In the present study, we approached this issue systematically by investigating transfer effects from WM training to different aspects of executive functioning. Our training task was a demanding WM task that requires simultaneous performance of a visual and an auditory n-back task, while the transfer tasks tapped WM updating, coordination of the performance of multiple simultaneous tasks (i.e., dual-tasks and sequential tasks (i.e., task switching, and the temporal distribution of attentional processing. Additionally, we examined whether WM training improves reasoning abilities; a hypothesis that has so far gained mixed support. Following training, participants showed improvements in the trained task as well as in the transfer WM updating task. As for the other executive functions, trained participants improved in a task switching situation and in attentional processing. There was no transfer to the dual-task situation or to reasoning skills. These results therefore confirm previous findings that WM can be trained, and additionally, they show that the training effects can generalize to various other tasks tapping on executive functions.

  12. Work engagement: drivers and effects

    NARCIS (Netherlands)

    Bakhuys Roozeboom, M.M.C.; Schelvis, R.

    2014-01-01

    The concept of work engagement fits into the tradition of positive psychology, a recent paradigm shift in psychology which focuses on mental health rather than mental illness. This article gives an introduction to the concept of work engagement. Different definitions and viewpoints of the work

  13. Executive Functions and Working Memory Behaviours in Children with a Poor Working Memory

    Science.gov (United States)

    St. Clair-Thompson, Helen L.

    2011-01-01

    Previous research has suggested that working memory difficulties play an integral role in children's underachievement at school. However, working memory is just one of several executive functions. The extent to which problems in working memory extend to other executive functions is not well understood. In the current study 38 children with a poor…

  14. The Acchivement Social Function Principal Contract in the Work Environment

    OpenAIRE

    Silva, Leda Maria Messias da; CESUMAR

    2008-01-01

    The following essay, aiming the work environment, deals with the acchivement of Social Function Principal Contract in the work environment. The work environment must be healthy, balanced, decent so that the worker may execute his/her activities eficently and well, preserving his/her dignity being helped by everyone in the process: employer, employee and also the state in the role of promoter of public policies. In the end, presents proposals that help in the work place and the social function...

  15. Surface energy and work function of the light actinides

    DEFF Research Database (Denmark)

    Kollár, J.; Vitos, Levente; Skriver, Hans Lomholt

    1994-01-01

    We have calculated the surface energy and work function of the light actinides Fr, Ra, Ac, Th, Pa, U, Np, and Pu by means of a Green's-function technique based on the linear-muffin-tin-orbitals method within the tight-binding representation. In these calculations we apply an energy functional which....... The calculated surface energies and work functions are in good agreement with the limited experimental data....

  16. Flavanol-rich chocolate acutely improves arterial function and working memory performance counteracting the effects of sleep deprivation in healthy individuals.

    Science.gov (United States)

    Grassi, Davide; Socci, Valentina; Tempesta, Daniela; Ferri, Claudio; De Gennaro, Luigi; Desideri, Giovambattista; Ferrara, Michele

    2016-07-01

    Sleep deprivation is a risk factor for cardiovascular disease. Cocoa flavonoids exert cardiovascular benefits and neuroprotection. Whether chocolate consumption may mitigate detrimental effects of sleep loss on cognitive performance and cardiovascular parameters has never been studied. We investigated the effects of flavanol-rich chocolate consumption on cognitive skills and cardiovascular parameters after sleep deprivation. Thirty-two healthy participants underwent two baseline sessions after one night of undisturbed sleep and two experimental sessions after one night of total sleep deprivation. Two hours before each testing session, participants were randomly assigned to consume high or poor flavanol chocolate bars. During the tests were evaluated, the Psychomotor Vigilance Task and a working memory task, office SBP and DBP, flow-mediated dilation and pulse-wave velocity. Sleep deprivation increased SBP/DBP. SBP/DBP and pulse pressure were lower after flavanol-rich treatment respect to flavanol-poor treatment (SBP: 116.9 ± 1.6 vs. 120.8 ± 1.9 mmHg, respectively, P = 0.00005; DBP: 70.5 ± 1.2 vs. 72.3 ± 1.2 mmHg, respectively, P = 0.01; pulse pressure: 46.4 ± 1.3 vs. 48.4 ± 1.5 mmHg, P = 0.004). Sleep deprivation impaired flow-mediated dilation (5.5 ± 0.5 vs. 6.5 ± 0.6%, P = 0.02), flavanol-rich, but not flavanol-poor chocolate counteracted this alteration (flavanol-rich/flavanol-poor chocolate: 7.0 ± 0.6 vs. 5.0 ± 0.4%, P = 0.000001). Flavanol-rich chocolate mitigated the pulse-wave velocity increase (P = 0.001). Flavanol-rich chocolate preserved working memory accuracy in women after sleep deprivation. Flow-mediated dilation correlated with working memory performance accuracy in the sleep condition (P = 0.04). Flavanol-rich chocolate counteracted vascular impairment after sleep deprivation and restored working memory performance. Improvement in cognitive performance could be because

  17. Hearing aid noise suppression and working memory function.

    Science.gov (United States)

    Neher, Tobias; Wagener, Kirsten C; Fischer, Rosa-Linde

    2018-01-09

    Research findings concerning the relation between benefit from hearing aid (HA) noise suppression and working memory function are inconsistent. The current study thus investigated the effects of three noise suppression algorithms on auditory working memory and the relation with reading span. Using a computer simulation of bilaterally fitted HAs, four settings were tested: (1) unprocessed, (2) directional microphones, (3) single-channel noise reduction, and (4) binaural coherence-based noise reduction. Settings 2-4 were matched in terms of the speech-weighted signal-to-noise ratio (SNR) improvement. Auditory working memory was assessed at +6 dB SNR using listening span and N-back paradigms. Twenty experienced HA users aged 55-80 years with large differences in reading span. For the listening span measurements, there was an influence of HA setting on sentence-final word recognition and recall, with the directional microphones leading to ∼6% better performance than the single-channel noise reduction. For the N-back measurements, there was substantial test-retest variability and no influence of HA setting. No interactions with reading span were found. HA noise suppression may affect the recognition and recall of speech at positive SNRs, irrespective of individual reading span. Future work should improve the reliability of the auditory working memory measurements.

  18. The effects of work alienation on organizational commitment, work effort and work-to-family enrichment

    NARCIS (Netherlands)

    L.G. Tummers (Lars); L. den Dulk (Laura)

    2013-01-01

    textabstractAim: The aim of this study was to analyze the effects of work alienation on organizational commitment, work effort and work-to-family enrichment. Background: There is substantial research on the effects of work alienation on passive job performance, such as organizational commitment.

  19. Work functioning in persons with depressive and anxiety disorders : The role of specific psychopathological characteristics

    NARCIS (Netherlands)

    Plaisier, I.; Beekman, A.T.F.; de Graaf, R.; Smit, J. H.; van Dyck, R.; Penninx, Brenda

    Background: Depressive and anxiety disorders affect work functioning and cause high labour costs. Aims: To examine and compare psychopathological characteristics of depressive and anxiety disorders in their effect on work functioning. Method: In 1876 working participants of the Netherlands Study of

  20. Work function of elemental metals and its face dependence ...

    African Journals Online (AJOL)

    The stabilizing potentials and work functions of elemental metals were calculated for the flat surface, the (111), (100) and (110) faces using the stabilized jellium model. The calculated work functions were compared with experimental values and calculated values obtained using the ab initio method. The stabilizing ...

  1. The Work Function Associated with Ultra-relativistic Electron ...

    Indian Academy of Sciences (India)

    At absolute zero, the energy of the most energetic electrons in a metal is referred to as the Fermi energy; the work function of a metal is then equal to the energy required to raise an electron with the Fermi energy to the energy level corre- sponding to an electron at rest in vacuum. The work function of a semiconductor or.

  2. Works Council Effectiveness: Determinants and Outcomes

    NARCIS (Netherlands)

    Sapulete, S.

    2013-01-01

    This thesis aimed to gain more insights into works council effectiveness in two ways: 1. studying the influence of works council presence on organizational outcomes; and, 2. studying the determinants of works council effectiveness. We found that productivity increases with the presence of a works

  3. Towards a sustainable healthy working life: associations between chronological age, functional age and work outcomes.

    Science.gov (United States)

    Koolhaas, Wendy; van der Klink, Jac J L; Groothoff, Johan W; Brouwer, Sandra

    2012-06-01

    The aims of this study were: (i) to determine the relation between chronological and functional age; (ii) to examine the association between chronological age and work outcomes; and (iii) to examine the association between functional age and work outcomes. An overview of the most reported work outcomes is outlined. Chronological age refers to the calendar age; functional age was measured with perceived health status (SF-36) and the presence of a chronic health condition. Perspectives on experienced problems, barriers, facilitators and support needs due to ageing and the Work Ability Index were gathered out as work outcomes. The association of chronological and functional age of workers aged ≥45 years (n = 2971) on work outcomes were significant but small, except for the presence of a chronic health condition. The presence of a chronic health condition was not related to chronological age. Older workers (60-64 years) reported better scores on social functioning, mental health and vitality compared with workers aged 45-59 years. Most reported problems due to ageing were energy decline, muscle function decline, concentration lapses and memory deterioration. Experienced barriers were concentration, work pace problems and mobility; facilitators were support from colleagues, informal relations at work and supervisors. Individual agreement had to be met to continue working life. This study confirmed that both chronological and functional age were associated with a decrease in work outcomes. Workers >60 years did not experience more problems and barriers compared with workers between 45 and 49 years of age.

  4. Towards a sustainable healthy working life : associations between chronological age, functional age and work outcomes

    NARCIS (Netherlands)

    Koolhaas, Wendy; van der Klink, Jac J. L.; Groothoff, Johan W.; Brouwer, Sandra

    Background: The aims of this study were: (i) to determine the relation between chronological and functional age; (ii) to examine the association between chronological age and work outcomes; and (iii) to examine the association between functional age and work outcomes. An overview of the most

  5. Impaired work functioning due to common mental disorders in nurses and allied health professionals: the Nurses Work Functioning Questionnaire.

    Science.gov (United States)

    Gärtner, F R; Nieuwenhuijsen, K; van Dijk, F J H; Sluiter, J K

    2012-02-01

    Common mental disorders (CMD) negatively affect work functioning. In the health service sector not only the prevalence of CMDs is high, but work functioning problems are associated with a risk of serious consequences for patients and healthcare providers. If work functioning problems due to CMDs are detected early, timely help can be provided. Therefore, the aim of this study is to develop a detection questionnaire for impaired work functioning due to CMDs in nurses and allied health professionals working in hospitals. First, an item pool was developed by a systematic literature study and five focus group interviews with employees and experts. To evaluate the content validity, additional interviews were held. Second, a cross-sectional assessment of the item pool in 314 nurses and allied health professionals was used for item selection and for identification and corroboration of subscales by explorative and confirmatory factor analysis. The study results in the Nurses Work Functioning Questionnaire (NWFQ), a 50-item self-report questionnaire consisting of seven subscales: cognitive aspects of task execution, impaired decision making, causing incidents at work, avoidance behavior, conflicts and irritations with colleagues, impaired contact with patients and their family, and lack of energy and motivation. The questionnaire has a proven high content validity. All subscales have good or acceptable internal consistency. The Nurses Work Functioning Questionnaire gives insight into precise and concrete aspects of impaired work functioning of nurses and allied health professionals. The scores can be used as a starting point for purposeful interventions.

  6. Non-degenerate n-type doping by hydrazine treatment in metal work function engineered WSe2 field-effect transistor

    Science.gov (United States)

    Lee, Inyeal; Rathi, Servin; Li, Lijun; Lim, Dongsuk; Atif Khan, Muhammad; Kannan, E. S.; Kim, Gil-Ho

    2015-11-01

    We report a facile and highly effective n-doping method using hydrazine solution to realize enhanced electron conduction in a WSe2 field-effect transistor (FET) with three different metal contacts of varying work functions—namely, Ti, Co, and Pt. Before hydrazine treatment, the Ti- and Co-contacted WSe2 FETs show weak ambipolar behaviour with electron dominant transport, whereas in the Pt-contacted WSe2 FETs, the p-type unipolar behaviour was observed with the transport dominated by holes. In the hydrazine treatment, a p-type WSe2 FET (Pt contacted) was converted to n-type with enhanced electron conduction, whereas highly n-doped properties were achieved for both Ti- and Co-contacted WSe2 FETs with on-current increasing by three orders of magnitude for Ti. All n-doped WSe2 FETs exhibited enhanced hysteresis in their transfer characteristics, which opens up the possibility of developing memories using transition metal dichalcogenides.

  7. The effects of work alienation on organisational commitment, work effort and work-to-family enrichment.

    Science.gov (United States)

    Tummers, Lars G; Den Dulk, Laura

    2013-09-01

    The aim of this study was to analyse the effects of work alienation on organisational commitment, work effort and work-to-family enrichment. There is substantial research on the effects of work alienation on passive job performance, such as organisational commitment. However, studies analysing work alienation on active performance, such as work effort, and outside work, such as work-to-family enrichment, are scarce. Two dimensions of work alienation are considered: powerlessness and meaninglessness. Hypotheses are tested using surveys collected among a national sample of midwives in the Netherlands (respondents: 790, response rate 61%). the findings indicate that work alienation (powerlessness and meaninglessness) influence organisational commitment, work effort and--to a lesser extent--work-to-family enrichment. High work meaninglessness, in particular, has negative effects on these outcomes. When people feel that they have no influence in their work (hence, when they feel 'powerless') and especially when the feel that their work is not worthwhile (when they feel 'meaningless') this has substantial negative effects. Managers should increase the meaningfulness that people attach to their work, thereby maintaining a high-quality workforce. Possible strategies include: (1) improving person-job fit, (2) developing high-quality relationships, (3) better communicating the results people help to deliver. © 2013 John Wiley & Sons Ltd.

  8. Surface energy and work function of elemental metals

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Rosengaard, N. M.

    1992-01-01

    and noble metals, as derived from the surface tension of liquid metals. In addition, they give work functions which agree with the limited experimental data obtained from single crystals to within 15%, and explain the smooth behavior of the experimental work functions of polycrystalline samples......We have performed an ab initio study of the surface energy and the work function for six close-packed surfaces of 40 elemental metals by means of a Green’s-function technique, based on the linear-muffin-tin-orbitals method within the tight-binding and atomic-sphere approximations. The results...... are in excellent agreement with a recent full-potential, all-electron, slab-supercell calculation of surface energies and work functions for the 4d metals. The present calculations explain the trend exhibited by the surface energies of the alkali, alkaline earth, divalent rare-earth, 3d, 4d, and 5d transition...

  9. Overweight, obesity and work functioning : The role of working-time arrangements

    NARCIS (Netherlands)

    Nigatu, Yeshambel T.; van de Ven, Hardy A.; van der Klink, Jac J. L.; Brouwer, Sandra; Reijneveld, Sijmen A.; Bultmann, Ute

    Background: Obesity is associated with productivity loss, but little is known about how obese workers function at work and also the role of working-time arrangements on this association is lacking. Therefore, the aim of this study was to examine the association of overweight and obesity with work

  10. Working memory training improves cognitive function in VLBW preschoolers.

    Science.gov (United States)

    Grunewaldt, Kristine Hermansen; Løhaugen, Gro Christine Christiansen; Austeng, Dordi; Brubakk, Ann-Mari; Skranes, Jon

    2013-03-01

    Preterm born children perform poorer than term peers on tests of attention and executive functions including working memory tests. Our aim was to evaluate if preterm born preschoolers with very low birth weight (VLBW) would benefit from a computerized working memory training program and if the training would have a generalizing effect on memory, learning, attention, behavior, and anxiety. A prospective intervention study with a stepped wedge design where 20 VLBW preschoolers aged 5 to 6 years participated. The children trained with the Cogmed JM program for 10 to 15 minutes a day, 5 days a week over a 5-week period. Extensive neuropsychological assessment and parental questionnaires regarding behavior and anxiety were performed before and 4 weeks after intervention. The children improved significantly on trained (mean Start Index 42.1 [SD 6.3]), mean Max Index 60.6 [SD 5.7]), and nontrained working memory tasks (Spatial Span backward; 2.3 [before] to 3.6 [after training] [confidence interval {CI} -2.2 to -0.4] and Spatial Span total score; 6.4-8.3 [CI -3.7 to -0.1]). A generalization effect was found on auditory attention (49.6-58.2 [CI -15.5 to -1.6]), phonological awareness (9.3-12.6 [CI -5.2 to -1.4]), visual (memory for faces 20.0-24.9 [CI -7.4 to -2.5]), as well as verbal memory (narrative memory; 12.9-17.5 [CI -7.1 to -2.0], and sentence repetition 15.7-17.7 [CI -3.3 to -0.7]). This study shows that VLBW preschoolers benefit from a computerized working memory training program. We speculate that such training before starting school may prevent or reduce cognitive problems that impact educational achievement.

  11. Workers with health problems : three perspectives on functioning at work

    NARCIS (Netherlands)

    Abma, Femke I.; Bultmann, Ute; Varekamp, Inge; van der Klink, Jac J. L.

    2013-01-01

    Purpose: Our aims were (i) to explore why it is that one worker with a health problem is able to stay at work while the other is not, (ii) to identify signals for decreased functioning at work, and (iii) to explore if and how this can be measured. Method: We conducted three focus groups: with

  12. The Relationship Between Working Memory Capacity and Executive Functioning: Evidence for a Common Executive Attention Construct

    Science.gov (United States)

    McCabe, David P.; Roediger, Henry L.; McDaniel, Mark A.; Balota, David A.; Hambrick, David Z.

    2010-01-01

    Attentional control has been conceptualized as executive functioning by neuropsychologists and as working memory capacity by experimental psychologists. We examined the relationship between these constructs using a factor analytic approach in an adult lifespan sample. Several tests of working memory capacity and executive function were administered to over 200 subjects between the ages of 18-90 years old, along with tests of processing speed and episodic memory. The correlation between working memory capacity and executive functioning constructs was very strong (r = .97), but correlations between these constructs and processing speed were considerably weaker (r's ≈ .79). Controlling for working memory capacity or executive function eliminated age effects on episodic memory, and working memory capacity or executive function accounted for variance in episodic memory beyond that accounted for by processing speed. We conclude that tests of working memory capacity and executive function share a common underlying executive attention component that is strongly predictive of higher-level cognition. PMID:20230116

  13. Reduced work function of graphene by metal adatoms

    Energy Technology Data Exchange (ETDEWEB)

    Legesse, Merid; Mellouhi, Fedwa El; Bentria, El Tayeb; Madjet, Mohamed E. [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha (Qatar); Fisher, Timothy S. [School of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907 (United States); Kais, Sabre [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha (Qatar); Department of Chemistry and Physics, Purdue University, West Lafayette, IN 46323 (United States); College of Science and Engineering, Hamad Bin Khalifa University, Doha (Qatar); Alharbi, Fahhad H., E-mail: falharbi@qf.org.qa [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha (Qatar); College of Science and Engineering, Hamad Bin Khalifa University, Doha (Qatar)

    2017-02-01

    Highlights: • Using DFT, the maximum reduction of graphene workfunction is investigated. This is important for many applications. • The calculations show that the adatoms prefer to relax at hollow sites. • The transfer of electrons from the adatoms to graphene shifts up the Fermi level. So, graphene becomes metallic. • For those dopants that have been used experimentally, the calculations agree with the experimental data. • We found that 8% doping by Cs reduces the work function to 2.05 eV. - Abstract: In this paper, the work function of graphene doped by different metal adatoms and at different concentrations is investigated. Density functional theory is used to maximize the reduction of the work function. In general, the work function drops significantly before reaching saturation. For example in the case of Cs doping, the work function saturates at 2.05 eV with a modest 8% doping. The adsorption of different concentrations on metal adatoms on graphene is also studied. Our calculations show that the adatoms prefer to relax at hollow sites. The transfer of electron from metallic dopants to the graphene for all the studied systems shifts the Fermi energy levels above the Dirac-point and the doped graphenes become metallic. The value of Fermi energy shifts depends on the type of metallic dopants and its concentrations. A detail analysis of the electronic structure in terms of band structure and density of states, absorption energy, and charge transfer for each adatom-graphene system is presented.

  14. Does polycystic ovary syndrome affect cognition? : A functional magnetic resonance imaging study exploring working memory

    NARCIS (Netherlands)

    Soleman, Remi S; Kreukels, Baudewijntje P C; Veltman, Dick J; Cohen-Kettenis, Peggy T; Hompes, Peter G A; Drent, Madeleine L; Lambalk, Cornelis B

    OBJECTIVE: To study effects of overexposure to androgens and subsequent antiandrogenic treatment on brain activity during working memory processes in women with polycystic ovary syndrome (PCOS). DESIGN: In this longitudinal study, working memory function was evaluated with the use of functional

  15. Systems and methods for producing low work function electrodes

    Science.gov (United States)

    Kippelen, Bernard; Fuentes-Hernandez, Canek; Zhou, Yinhua; Kahn, Antoine; Meyer, Jens; Shim, Jae Won; Marder, Seth R.

    2015-07-07

    According to an exemplary embodiment of the invention, systems and methods are provided for producing low work function electrodes. According to an exemplary embodiment, a method is provided for reducing a work function of an electrode. The method includes applying, to at least a portion of the electrode, a solution comprising a Lewis basic oligomer or polymer; and based at least in part on applying the solution, forming an ultra-thin layer on a surface of the electrode, wherein the ultra-thin layer reduces the work function associated with the electrode by greater than 0.5 eV. According to another exemplary embodiment of the invention, a device is provided. The device includes a semiconductor; at least one electrode disposed adjacent to the semiconductor and configured to transport electrons in or out of the semiconductor.

  16. Pulmonary Function Tests and Work-Related Respiratory and Allergic

    OpenAIRE

    Boskabady Mohammad Hosein; Taheri Ehsan; Ahmadi Sina; Ebrahimi Kolsoumeh; Soudaneh Malihe; Mohammadi Fatemeh; Sabourhasanzadeh Alireza

    2009-01-01

    Bakers are frequently exposed to various irritant chemicals during work which can induce respiratory problems. In this study, pulmonary function tests and self-reported respiratory and allergic symptoms in bakers were compared with matched control subjects. The frequency of respiratory and allergic symptoms was evaluated in a sample of 58 Iranian bakers and 58 control subjects using a questionnaire. Pulmonary function tests (PFT) were also measured in all participants. All respiratory symptom...

  17. Work functioning in persons with depressive and anxiety disorders: the role of specific psychopathological characteristics.

    Science.gov (United States)

    Plaisier, I; Beekman, A T F; de Graaf, R; Smit, J H; van Dyck, R; Penninx, B W J H

    2010-09-01

    Depressive and anxiety disorders affect work functioning and cause high labour costs. To examine and compare psychopathological characteristics of depressive and anxiety disorders in their effect on work functioning. In 1876 working participants of the Netherlands Study of Depression and Anxiety (NESDA) associations of presence, severity, comorbidity, duration and type of DSM-IV anxiety and depressive disorders with both absenteeism (2 weeks) and work performance (reduced and impaired) were assessed. People with current depressive disorders had 7.10 times greater odds for the risk of >2 weeks work-absence and 5.67 greater odds for the risk of impaired work performance, while persons with current anxiety disorders had 1.84 and 2.13 greater odds for the risk of >2 weeks absence and impaired work performance, respectively. Even when persons were recovered from depressive and anxiety disorders, they still had a higher risk of poor work functioning. Persons with comorbidity, chronic depressive disorder, a generalized anxiety disorder, and more severity of both anxiety and depressive disorder had higher odds for the risk of absenteeism and decreased work performance. Anxiety disorders have significant negative impact on work functioning, although smaller than the effect of depressive disorders. Comorbidity, severity, type and duration of the disorder, differentiate the risk of poor work functioning. 2010 Elsevier B.V. All rights reserved.

  18. Functional work breaks in a high-demanding work environment: an experimental field study.

    Science.gov (United States)

    Scholz, André; Ghadiri, Argang; Singh, Usha; Wendsche, Johannes; Peters, Theo; Schneider, Stefan

    2018-02-01

    Work breaks are known to have positive effects on employees' health, performance and safety. Using a sample of twelve employees working in a stressful and cognitively demanding working environment, this experimental field study examined how different types of work breaks (boxing, deep relaxation and usual breaks) affect participants' mood, cognitive performance and neurophysiological state compared to a control condition without any break. In a repeated measures experimental design, cognitive performance was assessed using an auditory oddball test and a Movement Detection Test. Brain cortical activity was recorded using electroencephalography. Individual's mood was analysed using a profile of mood state. Although neurophysiological data showed improved relaxation of cortical state after boxing (vs. 'no break' and 'deep relaxation'), neither performance nor mood assessment showed similar results. It remains questionable whether there is a universal work break type that has beneficial effects for all individuals. Practitioner Summary: Research on work breaks and their positive effects on employees' health and performance often disregards break activities. This experimental field study in a stressful working environment investigated the effect of different work break activities. A universal work break type that is beneficial for this workplace could not be identified.

  19. Functional Requirements for an Electronic Work Package System

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna H. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-12-01

    This document provides a set of high level functional requirements for a generic electronic work package (eWP) system. The requirements have been identified by the U.S. nuclear industry as a part of the Nuclear Electronic Work Packages - Enterprise Requirements (NEWPER) initiative. The functional requirements are mainly applied to eWP system supporting Basic and Moderate types of smart documents, i.e., documents that have fields for recording input such as text, dates, numbers, and equipment status, and documents which incorporate additional functionalities such as form field data “type“ validation (e.g. date, text, number, and signature) of data entered and/or self-populate basic document information (usually from existing host application meta data) on the form when the user first opens it. All the requirements are categorized by the roles; Planner, Supervisor, Craft, Work Package Approval Reviewer, Operations, Scheduling/Work Control, and Supporting Functions. The categories Statistics, Records, Information Technology are also included used to group the requirements. All requirements are presented in Section 2 through Section 11. Examples of more detailed requirements are provided for the majority of high level requirements. These examples are meant as an inspiration to be used as each utility goes through the process of identifying their specific requirements. The report’s table of contents provides a summary of the high level requirements.

  20. Tuning of metal work functions with self-assembled monolayers

    NARCIS (Netherlands)

    de Boer, B; Hadipour, A; Mandoc, MM; van Woudenbergh, T; Blom, PWM

    2005-01-01

    Work functions of gold and silver are varied by over 1.4 and 1.7 eV, respectively, by using self-assembled monolayers. Using these modified electrodes, the hole current in a poly(2-methoxy-5-(2'-ethylhexyloxy)- 1,4-phenylene vinylene) light-emitting diode is tuned by more than six orders of

  1. Postadsorption Work Function Tuning via Hydrogen Pressure Control.

    Science.gov (United States)

    Edlbauer, Hermann; Zojer, Egbert; Hofmann, Oliver T

    2015-12-03

    The work function of metal substrates can be easily tuned, for instance, by adsorbing layers of molecular electron donors and acceptors. In this work, we discuss the possibility of changing the donor/acceptor mixing ratio reversibly after adsorption by choosing a donor/acceptor pair that is coupled via a redox reaction and that is in equilibrium with a surrounding gas phase. We discuss such a situation for the example of tetrafluoro-1,4-benzenediol (TFBD)/tetrafluoro-1,4-benzoquinone (TFBQ), adsorbed on Cu(111) and Ag(111) surfaces. We use density functional theory and ab initio thermodynamics to show that arbitrary TFBD/TFBQ mixing ratios can be set using hydrogen pressures attainable in low to ultrahigh vacuum. Adjusting the mixing ratio allows modifying the work function over a range of about 1 eV. Finally, we contrast single-species submonolayers with mixed layers to discuss why the resulting inhomogeneities in the electrostatic energy above the surface have different impacts on the interfacial level alignment and the work function.

  2. Functional brain activation associated with working memory training and transfer.

    Science.gov (United States)

    Clark, Cameron M; Lawlor-Savage, Linette; Goghari, Vina M

    2017-09-15

    While behavioural trials of working memory (WM) training have received much attention in recent years, a lesser explored parallel approach is functional neuroimaging. A small literature has suggested a complex time course for functional activation pattern changes following WM training (i.e. not simply increasing or decreasing due to training); however, no study to date has examined such neuroplastic effects in both the training task (dual n-back) and the fluid intelligence transfer task to which the training is purported to transfer (Raven's Matrices). This study investigated neural correlates of WM training in healthy young adults randomized to six weeks of WM training, or an active control condition (processing speed training) with a pre- and post-training fMRI design. Results indicated significant reductions in activation for the WM trained group in key WM-task related areas for trained WM tasks after training compared to the processing speed active control group. The same pattern of training related decreases in activation for the WM trained group was not observed for the transfer task, which is consistent with null results for all cognitive outcomes of the present trial. The observed pattern of results suggests that repetitive practice with a complex task does indeed lead to neuroplastic processes that very likely represent the reduced demand for attentional control while sub-components of the task become more routinized with practice. We suggest that future research investigate neural correlates of WM training in populations for which WM itself is impaired and/or behavioural trials of WM training have returned more promising results. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Dithiocarbamate Self-Assembled Monolayers as Efficient Surface Modifiers for Low Work Function Noble Metals

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Dominik; Schäfer, Tobias; Schulz, Philip; Jung, Sebastian; Rittich, Julia; Mokros, Daniel; Segger, Ingolf; Maercks, Franziska; Effertz, Christian; Mazzarello, Riccardo; Wuttig, Matthias

    2016-09-06

    Tuning the work function of the electrode is one of the crucial steps to improve charge extraction in organic electronic devices. Here, we show that N,N-dialkyl dithiocarbamates (DTC) can be effectively employed to produce low work function noble metal electrodes. Work functions between 3.1 and 3.5 eV are observed for all metals investigated (Cu, Ag, and Au). Ultraviolet photoemission spectroscopy (UPS) reveals a maximum decrease in work function by 2.1 eV as compared to the bare metal surface. Electronic structure calculations elucidate how the complex interplay between intrinsic dipoles and dipoles induced by bond formation generates such large work function shifts. Subsequently, we quantify the improvement in contact resistance of organic thin film transistor devices with DTC coated source and drain electrodes. These findings demonstrate that DTC molecules can be employed as universal surface modifiers to produce stable electrodes for electron injection in high performance hybrid organic optoelectronics.

  4. Career Development and Personal Functioning Differences between Work-Bound and Non-Work Bound Students

    Science.gov (United States)

    Creed, Peter A.; Patton, Wendy; Hood, Michelle

    2010-01-01

    We surveyed 506 Australian high school students on career development (exploration, planning, job-knowledge, decision-making, indecision), personal functioning (well-being, self-esteem, life satisfaction, school satisfaction) and control variables (parent education, school achievement), and tested differences among work-bound, college-bound and…

  5. Trajectories of Work-Related Functional Impairment prior to Suicide.

    Science.gov (United States)

    Wang, Mo; Björkenstam, Charlotte; Alexanderson, Kristina; Runeson, Bo; Tinghög, Petter; Mittendorfer-Rutz, Ellenor

    2015-01-01

    Work-related functional impairment in terms of sickness absence and disability pension (SA/DP) has been reported to be associated with subsequent suicide. However, there is only limited knowledge on SA/DP patterns prior to suicide. The aim was to identify trajectories of work-related functional impairment prior to suicide and to describe associations of socio-demographic and medical factors with such trajectories. This is a population-based retrospective cohort study of the 4 209 individuals aged 22-65 years who committed suicide during 2007-2010 in Sweden. Work-related functional impairment was measured as mean annual number of months of SA/DP. We analyzed trajectories of SA/DP during five years prior to suicide (i.e., 2002-2009) by a group-based trajectory method. Associations between socio-demographic and medical factors with different groups of trajectories were estimated by chi2-test and multinomial logistic regression. Five different functional impairment trajectory groups were identified prior to suicide. One group had constant low levels of SA/DP (46%), while 30% had constant high levels of SA/DP. Two groups (16%) showed increasing number of SA/DP months. The remaining 7% showed decreasing number of SA/DP months before the suicide. Sex, age, educational level, family situation, and diagnosis-specific healthcare were significantly associated with different trajectory groups (Likelihood ratio X2 tests suicide attempts were found in the group with constant low levels. Opposite characteristics were displayed in the group with constant high levels. This study identified five different groups of work-related functional impairment trajectories before suicide. These differences might be partly explained by the variations in socio-demographic profiles and health care consumptions five years before suicide.

  6. Influence of estradiol on functional brain organization for working memory.

    Science.gov (United States)

    Joseph, Jane E; Swearingen, Joshua E; Corbly, Christine R; Curry, Thomas E; Kelly, Thomas H

    2012-02-01

    Working memory is a cognitive function that is affected by aging and disease. To better understand the neural substrates for working memory, the present study examined the influence of estradiol on working memory using functional magnetic resonance imaging. Pre-menopausal women were tested on a verbal n-back task during the early (EF) and late follicular (LF) phases of the menstrual cycle. Although brain activation patterns were similar across the two phases, the most striking pattern that emerged was that estradiol had different associations with the two hemispheres. Increased activation in left frontal circuitry in the LF phase was associated with increased estradiol levels and decrements in working memory performance. In contrast, increased activation in right hemisphere regions in the LF phase was associated with improved task performance. The present study showed that better performance in the LF than the EF phase was associated with a pattern of reduced recruitment of the left-hemisphere and increased recruitment of the right-hemisphere in the LF compared to EF phase. We speculate that estradiol interferes with left-hemisphere working-memory processing in the LF phase, but that recruitment of the right hemisphere can compensate for left-hemisphere interference. This may be related to the proposal that estradiol can reduce cerebral asymmetries by modulating transcallosal communication (Hausmann, 2005). Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Functional Impairments and Work-Related Outcomes in Breast Cancer Survivors: A Systematic Review.

    Science.gov (United States)

    Bijker, Rimke; Duijts, Saskia F A; Smith, Sherzel N; de Wildt-Liesveld, Renée; Anema, Johannes R; Regeer, Barbara J

    2017-10-30

    Purpose Work participation after breast cancer treatment is generally negatively affected. Occupational health professionals might improve work-related outcomes by bridging the gap between sick-listed employees' levels of functioning and work demands. To aid them in this task, this review explored the association between functional impairments and work-related outcomes in breast cancer survivors. Methods Publications from January 2000-March 2016 were identified through five online databases (i.e. Pubmed, EMBASE, PsycINFO, CINAHL and the Cochrane Library). Quantitative and qualitative studies were included if they focused on functional impairments and work-related outcomes in breast cancer survivors. Two reviewers independently selected studies, extracted data and performed quality assessment. Results The search identified 998 studies, of which 20 studies met eligibility criteria. Impairments in physical functioning negatively affected return to work (RTW) and work ability in quantitative and qualitative studies. Studies measuring cognitive functioning with tests found no association with work-related outcomes, whereas the results of studies using self-reported measures were ambiguous. Social functioning was less commonly investigated and findings differed across work-related outcomes. Emotional functioning was not associated with work-related outcomes in quantitative studies, while in qualitative studies feelings such as insecurity were described as influencing RTW. Conclusions Functional impairments can severely hamper work participation in breast cancer survivors. This provides important opportunities for occupational health professionals to enhance RTW in breast cancer survivors, such as adequately addressing illness perceptions and work expectations. Ongoing research is warranted to aid occupational health professionals in providing effective vocational guidance and improve work-related outcomes in breast cancer survivors.

  8. Work function modifications of graphite surface via oxygen plasma treatment

    Science.gov (United States)

    Duch, J.; Kubisiak, P.; Adolfsson, K. H.; Hakkarainen, M.; Golda-Cepa, M.; Kotarba, A.

    2017-10-01

    The surface modification of graphite by oxygen plasma was investigated experimentally (X-ray diffraction, nanoparticle tracking analysis, laser desorption ionization mass spectrometry, thermogravimetry, water contact angle) and by molecular modelling (Density Functional Theory). Generation of surface functional groups (mainly sbnd OHsurf) leads to substantial changes in electrodonor properties and wettability gauged by work function and water contact angle, respectively. The invoked modifications were analyzed in terms of Helmholtz model taking into account the theoretically determined surface dipole moment of graphite-OHsurf system (μ = 2.71 D) and experimentally measured work function increase (from 0.75 to 1.02 eV) to determine the sbnd OH surface coverage (from 0.70 to 1.03 × 1014 groups cm-2). Since the plasma treatment was confined to the surface, the high thermal stability of the graphite material was preserved as revealed by the thermogravimetric analysis. The obtained results provide a suitable quantitative background for tuning the key operating parameters of carbon electrodes: electronic properties, interaction with water and thermal stability.

  9. The Effect of Volunteer Work on Employability

    DEFF Research Database (Denmark)

    Petrovski, Erik; Dencker-Larsen, Sofie; Holm, Anders

    2017-01-01

    sample of 1,867 individuals of working age. The survey data are linked to administrative registers containing individual-level data on unemployment. A combination of detailed controls, lagged dependent variables, and instrumental variable regression is used to determine cause and effect. Our findings......In addition to benefiting others, volunteer work is argued to supply volunteers themselves with skills, reputation, and social connections that increase overall employability. We test this hypothesized causal link between volunteer work and employability with a high-quality 2012 Danish survey...

  10. Work function mediated by deposition of ultrathin polar FeO on Pt(111)

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shuangzan; Qin, Zhihui; Guo, Qinmin; Cao, Gengyu, E-mail: gycao@wipm.ac.cn

    2017-01-15

    Highlights: • Growth of FeO layers on Pt(111) is found to consecutively reduce the work function of the system. • The electrostatic compression effect and the structural relaxation make major contributions to the reductions. • Significant rectifying effect observed in the FeO layer is induced by band alignment shift as work function changing. - Abstract: Significant work function changes from bare Pt(111) surface to 1 monolayer and 2 monolayers of ultrathin iron oxide (FeO) films on it are investigated by means of scanning tunneling microscopy/spectroscopy (STM/STS). With FeO layer-by-layer growth, a continuous reduction of the work function along with the surface vacuum level (VL) shifting is observed. We found that the compression of the electron spill-out at the metal-oxide interface and the substantial reconstruction of 2 ML FeO film, respectively, make major contributions to the first and the second reductions of the work function. The rectifying effect in FeO films is also observed, which is attributed to the downward shift of band alignment imposed by the total change in surface dipole. Our work shows that the polar oxide films play an important role to adjust surface electronic structures for enhancing device functionality.

  11. Working Memory and Executive Function Profiles of Individuals with Borderline Intellectual Functioning

    Science.gov (United States)

    Alloway, T. P.

    2010-01-01

    Background: The aim of the present study was to investigate the following issues: (1) Do students with borderline intellectual functioning have a pervasive pattern of impaired working memory skills across both verbal and visuo-spatial domains? (2) Is there evidence for impairment in executive function skills, and which tasks indicate greater…

  12. [Shift work and night work: what effect on blood pressure?].

    Science.gov (United States)

    Cassat, M; Wuerzner, G; Burnier, M

    2015-09-09

    Shift work has become more and more common for the last thirty years. By definition, shift work disturbs the circadian rhythm and the internal clock. Even if the pathophysiological mechanisms are not well understood, a greater cardiovascular risk has been attributed to shift work. Cross-sectional and cohort studies have identified an association between shift work and an elevated blood pressure. Shift workers also present a higher incidence of hypertension and progression than day workers. Unfortunately, the heterogeneity of the studies, the multiple confounding factors, as well as the complexity to achieve a suitable comparison group make it impossible to draw firm clinical evidence. Nevertheless, this population needs a medical follow-up focused on the cardiovascular risks and blood pressure.

  13. Rheumatic effects of vibration at work

    Science.gov (United States)

    Palmer, Keith T; Bovenzi, Massimo

    2016-01-01

    Occupational exposures to vibration come in many guises and are very common at a population level. It follows that an important minority of working-aged patients seen by medical services will have been exposed to this hazard of employment. Vibration can cause human health effects which may manifest in the patients that rheumatologists see. In this chapter we identify the health effects of relevance to them, and review their epidemiology, pathophysiology, clinical presentation, differential diagnosis, and vocational and clinical management. On either side of this, we describe the nature and assessment of the hazard, the scale and common patterns of exposure to vibration in the community, and the legal basis for controlling health risks, and comment on the role of health surveillance in detecting early adverse effects and what can be done to prevent the rheumatic effects of vibration at work. PMID:26612239

  14. Fabrication and Measurement of Low Work Function Cesiated Dispenser Photocathodes

    CERN Document Server

    Moody, Nathan A; Jensen, Kevin

    2005-01-01

    Photoinjector performance is a limiting factor in the continued development of high powered FELs and electron beam-based accelerators. Presently available photocathodes are plagued with limited efficiency and short lifetime in an RF-gun environment, due to contamination or evaporation of a photosensitive surface layer. An ideal photocathode should have high efficiency at long wavelengths, long lifetime in practical vacuum environments, and prompt emission. Cathodes with high efficiency typically have limited lifetime, and vice versa, and the needs of the photocathode are generally at odds with those of the drive laser. A potential solution is the low work function dispenser cathode, where lifetime issues are overcome by periodic in situ regeneration that restores the photosensitive surface layer, analogous to those used in the microwave power tube industry. This work reports on the fabrication techniques and performance of cesiated metal photocathodes and cesiated dispenser cathodes, with a focus on understan...

  15. Note: Work function change measurement via improved Anderson method

    Energy Technology Data Exchange (ETDEWEB)

    Sabik, A., E-mail: sabik@ifd.uni.wroc.pl; Gołek, F.; Antczak, G. [Institute of Experimental Physics, University of Wrocław, Wrocław (Poland)

    2015-05-15

    We propose the modification to the Anderson method of work function change (Δϕ) measurements. In this technique, the kinetic energy of the probing electrons is already low enough for non-destructive investigation of delicate molecular systems. However, in our implementation, all electrodes including filament of the electron gun are polarized positively. As a consequence, electron bombardment of any elements of experimental system is eliminated. Our modification improves cleanliness of the ultra-high vacuum system. As an illustration of the solution capabilities, we present Δϕ of the Ag(100) surface induced by cobalt phthalocyanine layers.

  16. Does polycystic ovary syndrome affect cognition? A functional magnetic resonance imaging study exploring working memory.

    Science.gov (United States)

    Soleman, Remi S; Kreukels, Baudewijntje P C; Veltman, Dick J; Cohen-Kettenis, Peggy T; Hompes, Peter G A; Drent, Madeleine L; Lambalk, Cornelis B

    2016-05-01

    To study effects of overexposure to androgens and subsequent antiandrogenic treatment on brain activity during working memory processes in women with polycystic ovary syndrome (PCOS). In this longitudinal study, working memory function was evaluated with the use of functional magnetic resonance imaging (MRI) in women with PCOS before and after antiandrogenic treatment. Department of reproductive medicine, university medical center. Fourteen women with PCOS and with hyperandrogenism and 20 healthy control women without any features of PCOS or other hormonal disorders. Antiandrogenic hormone treatment. Functional MRI response during a working memory task. At baseline women with PCOS showed more activation than the control group within the right superior parietal lobe and the inferior parietal lobe during task (all memory conditions). Task performance (speed and accuracy) did not differ between the groups. After antiandrogenic treatment the difference in overall brain activity between the groups disappeared and accuracy in the high memory load condition of the working memory task increased in women with PCOS. Women with PCOS may need additional neural resources during a working memory task compared with women without PCOS, suggesting less efficient executive functioning. This inefficiency may have effects on daily life functioning of women with PCOS. Antiandrogenic treatment appears to have a beneficial effect on this area of cognitive functioning. NTR2493. Copyright © 2016. Published by Elsevier Inc.

  17. Chronic pain disrupts ability to work by interfering with social function: A cross-sectional study.

    Science.gov (United States)

    Hengstebeck, Elizabeth; Roskos, Steven; Breejen, Karen; Arnetz, Bengt; Arnetz, Judy

    2017-10-01

    Some 100 million adults in the United States suffer from chronic pain. While research to date has focused primarily on pain interference with physical and psychological function and its effects on employment, few studies have examined the impact of pain interference on social functioning and its effects on employment. The aims of our study were to (1) evaluate the association between pain interference with ability to work and actual employment status among working age adults with chronic pain; and (2) evaluate pain interference with four types of functioning - cognitive, physical, psychological, and social - as possible mediators of pain interference with the ability to work. Data were collected via a self-selected sample of individuals visiting the American Chronic Pain Association (ACPA) website. The final dataset included 966 respondents. We examined the association between pain interference with the ability to work and employment in a population with chronic pain. We then analyzed pain interference with four types of functioning, physical, psychological, cognitive, and social, for their impact on the ability to work. Pain interference with ability to work was significantly inversely associated with employment status, i.e., the less that pain interfered with one's ability to work, the greater the likelihood of being employed. Moreover, pain interference with ability to work was a stronger predictor of employment status than an individual's rating of their pain intensity. Pain interference with social functioning partially mediated the effects of pain interference with cognitive and physical functioning and fully mediated the effects of pain intensity and pain interference with psychological functioning on pain interference with the ability to work. Results suggest that pain interference with social function may be a significant contributor to pain interference with ability to work in working age adults with chronic pain. In the development of effective solutions

  18. JOB MISMATCH – EFFECTS ON WORK PRODUCTIVITY

    Directory of Open Access Journals (Sweden)

    Magdalena Velciu

    2017-12-01

    Full Text Available Job matching and finding the best person to the right job inside the right company has become one of the most important and actual challenges of productivity. Not only full employment but the match between the employee and the job, in terms of educational level or field of activity, qualifications and skills of workforce; all have been the new gain of work productivity. Present article synthesizes the theoretical and empirical findings on effects of job mismatch by selecting the main findings about influence of job mismatches on work productivity including both employees and companies sides. on short term overeducation and overqualification could have a positive effect on productivity for one company, but on long term, mismatched worker would be affected by decreasing job satisfaction and lower wages. Also, at macroeconomic level, from a perspective of economy as a whole, job mismatches mean a loss of resources and human capital and could have negative effects on overall productivity. The opposite effects stay at the crossing between the employees, companies, policies and future development. In fact the effects of skill mismatch and productivity is a lost of work potential through inefficient resource (reallocation.

  19. The Effect of Work on Health and Work Ability

    NARCIS (Netherlands)

    S.M. Alavinia (Seyed Mahammad)

    2008-01-01

    textabstractIn many countries through the industrial world the population is aging. Despite an increased life expectancy, improved living conditions, and better health status, the average time people spend in paid work is decreasing. There are several mechanisms of withdrawal from the labor force

  20. Gestalt Effects in Visual Working Memory.

    Science.gov (United States)

    Kałamała, Patrycja; Sadowska, Aleksandra; Ordziniak, Wawrzyniec; Chuderski, Adam

    2017-01-01

    Four experiments investigated whether conforming to Gestalt principles, well known to drive visual perception, also facilitates the active maintenance of information in visual working memory (VWM). We used the change detection task, which required the memorization of visual patterns composed of several shapes. We observed no effects of symmetry of visual patterns on VWM performance. However, there was a moderate positive effect when a particular shape that was probed matched the shape of the whole pattern (the whole-part similarity effect). Data support the models assuming that VWM encodes not only particular objects of the perceptual scene but also the spatial relations between them (the ensemble representation). The ensemble representation may prime objects similar to its shape and thereby boost access to them. In contrast, the null effect of symmetry relates the fact that this very feature of an ensemble does not yield any useful additional information for VWM.

  1. Low work function material development for the microminiature thermionic converter.

    Energy Technology Data Exchange (ETDEWEB)

    Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan; Jennison, Dwight Richard

    2004-03-01

    Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.

  2. Probing local work function of electron emitting Si-nanofacets

    Science.gov (United States)

    Basu, Tanmoy; Som, Tapobrata

    2017-10-01

    Large area, Si-nanofacets are synthesized by obliquely incident low energy Ar+-ion-beam bombardment at room temperature (RT). The field emission properties of such nanofacets are studied based on current-voltage measurements and the Fowler-Nordheim equation. Low turn-on field with relatively high current density is obtained due to the shape and an overall rough morphology. We demonstrate a tunable field emission property from the silicon nanofacets by varying the ion exposure time. Atomic force microscopy (AFM) in conjunction with Kelvin probe force microscopy (KPFM) measurements provide the information on the aspect ratio and confirms the presence of native oxide layer near the apexes of the facets, respectively. The inhomogeneous oxidation leads to an increase in the local work function at the apexes of the facets, restricting the electron emission from the same. Due to its room temperature fabrication, the present method is of great significance to the low-cost vacuum field emission devices fabrication.

  3. Effects of chewing in working memory processing.

    Science.gov (United States)

    Hirano, Yoshiyuki; Obata, Takayuki; Kashikura, Kenichi; Nonaka, Hiroi; Tachibana, Atsumichi; Ikehira, Hiroo; Onozuka, Minoru

    2008-05-09

    It has been generally suggested that chewing produces an enhancing effect on cognitive performance-related aspects of memory by the test battery. Furthermore, recent studies have shown that chewing is associated with activation of various brain regions, including the prefrontal cortex. However, little is known about the relation between cognitive performances affected by chewing and the neuronal activity in specified regions in the brain. We therefore examined the effects of chewing on neuronal activities in the brain during a working memory task using fMRI. The subjects chewed gum, without odor and taste components, between continuously performed two- or three-back (n-back) working memory tasks. Chewing increased the BOLD signals in the middle frontal gyrus (Brodmann's areas 9 and 46) in the dorsolateral prefrontal cortex during the n-back tasks. Furthermore, there were more prominent activations in the right premotor cortex, precuneus, thalamus, hippocampus and inferior parietal lobe during the n-back tasks after the chewing trial. These results suggest that chewing may accelerate or recover the process of working memory besides inducing improvement in the arousal level by the chewing motion.

  4. Cross Functional Working and Concurrent Engineering – a UK Study

    Directory of Open Access Journals (Sweden)

    H. Williams

    2000-01-01

    Full Text Available This paper reports on the preliminary results of an investigative study into the implementation of concurrent engineering applied to new product development. Concurrent (or Simultaneous engineering is the term commonly given to creating new products using multi-disciplined teams of marketing, design, manufacturing and support functions together with supplier and customers. Such techniques have produced robust, low cost quality products in short concept to market times compared to traditional ones. The research investigated design management practice and performance in a number of organisations across a range of industrial sectors in the UK by means of a questionnaire survey. The results identify the current use of a variety of design practices and methodologies such as different organisational structures, the extent of cross-functional working, the use of design and phase reviews and the use of different technologies. They indicate that companies implementing CE are more successful in time to market performance than those who don’t implement CE. Factors most influencing the successful adoption of CE are design and phase reviews, and, to a lesser extent, the use of multifunctional teams and supplier partnerships.

  5. Written work: the social functions of Research Ethics Committee letters.

    Science.gov (United States)

    Dixon-Woods, Mary; Angell, Emma; Ashcroft, Richard E; Bryman, Alan

    2007-08-01

    Research Ethics Committees (RECs) are increasingly institutionalised as a feature of research practice, but have remained strangely neglected by social scientists. In this paper, we argue that analysis of letters from RECs to researchers offers important insights into how RECs operate. We report a traditional content analysis and an ethnographic content analysis of 141 letters to researchers, together with an analysis of the organisational and institutional arrangements for RECs in the UK. We show that REC letters perform three important social functions. First, they define what is deemed by a REC to be ethical practice for any particular application, and confer authority on that definition. They do this actively, through comments on particular aspects of proposals, and passively, through silences about other aspects. Second, they provide an account of the work of the REC, and function as a form of institutional display. Third, they specify the nature of the relationship between the REC and the applicant, casting the applicant in a supplicant role and requiring forms of docility. Writing and reading REC letters require highly specific competences, and engage both parties in a Bourdieusian "game" that discourages challenges from researchers. The authority of RECs' decisions derives not from their appeal to the moral superiority of any ethical position, but through their place in the organisational structure and the social positioning of the parties to the process thus implied. Letters are the critical point at which RECs act on researchers and their projects.

  6. Brain injury impairs working memory and prefrontal circuit function

    Directory of Open Access Journals (Sweden)

    Colin James Smith

    2015-11-01

    Full Text Available More than 2.5 million Americans suffer a traumatic brain injury (TBI each year. Even mild to moderate traumatic brain injury causes long-lasting neurological effects. Despite its prevalence, no therapy currently exists to treat the underlying cause of cognitive impairment suffered by TBI patients. Following lateral fluid percussion injury (LFPI, the most widely used experimental model of TBI, we investigated alterations in working memory and excitatory/inhibitory synaptic balance in the prefrontal cortex. LFPI impaired working memory as assessed with a T-maze behavioral task. Field excitatory postsynaptic potentials recorded in the prefrontal cortex were reduced in slices derived from brain-injured mice. Spontaneous and miniature excitatory postsynaptic currents onto layer 2/3 neurons were more frequent in slices derived from LFPI mice while inhibitory currents onto layer 2/3 neurons were smaller after LFPI. Additionally, an increase in action potential threshold and concomitant decrease in firing rate was observed in layer 2/3 neurons in slices from injured animals. Conversely, no differences in excitatory or inhibitory synaptic transmission onto layer 5 neurons were observed; however, layer 5 neurons demonstrated a decrease in input resistance and action potential duration after LFPI. These results demonstrate synaptic and intrinsic alterations in prefrontal circuitry that may underlie working memory impairment caused by TBI.

  7. The influence of shift work on cognitive functions and oxidative stress.

    Science.gov (United States)

    Özdemir, Pınar Güzel; Selvi, Yavuz; Özkol, Halil; Aydın, Adem; Tülüce, Yasin; Boysan, Murat; Beşiroğlu, Lütfullah

    2013-12-30

    Shift work influences health, performance, activity, and social relationships, and it causes impairment in cognitive functions. In this study, we investigated the effects of shift work on participants' cognitive functions in terms of memory, attention, and learning, and we measured the effects on oxidative stress. Additionally, we investigated whether there were significant relationships between cognitive functions and whole blood oxidant/antioxidant status of participants. A total of 90 health care workers participated in the study, of whom 45 subjects were night-shift workers. Neuropsychological tests were administered to the participants to assess cognitive function, and blood samples were taken to detect total antioxidant capacity and total oxidant status at 08:00. Differences in anxiety, depression, and chronotype characteristics between shift work groups were not significant. Shift workers achieved significantly lower scores on verbal memory, attention-concentration, and the digit span forward sub-scales of the Wechsler Memory Scale-Revised (WMS-R), as well as on the immediate memory and total learning sub-scales of the Auditory Verbal Learning Test (AVLT). Oxidative stress parameters were significantly associated with some types of cognitive function, including attention-concentration, recognition, and long-term memory. These findings suggest that night shift work may result in significantly poorer cognitive performance, particularly working memory. © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Mediating pathways and gender differences between shift work and subjective cognitive function.

    Science.gov (United States)

    Wong, Imelda S; Smith, Peter M; Ibrahim, Selahadin; Mustard, Cameron A; Gignac, Monique A M

    2016-11-01

    Increased injury risk among shift workers is often attributed to cognitive function deficits that come about as a result of sleep disruptions. However, little is known about the intermediate influences of other factors (eg, work stress, health) which may affect this relationship. In addition, gender differences in these the complex relationships have not been fully explored. The purpose of this study is to (1) identify the extent to which work and non-work factors mediate the relationship between shift work, sleep and subsequent subjective cognitive function; and (2) determine if the mediating pathways differ for men and women. Data from the 2010 National Population Health Survey was used to create a cross-sectional sample of 4255 employed Canadians. Using path modelling, we examined the direct and indirect relationships between shift work, sleep duration, sleep quality and subjective cognitive function. Multigroup analyses tested for significantly different pathways between men and women. Potential confounding effects of age and self-reported health and potential mediating effects of work stress were simultaneously examined. Work stress and sleep quality significantly mediated the effects of shift work on cognition. Age and health confounded the relationship between sleep quality and subjective cognition. No differences were found between men and women. Occupational health and safety programmes are needed to address stress and health factors, in addition to sleep hygiene, to effectively address cognitive function among shift workers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. Exposure-in-vivo containing interventions to improve work functioning of workers with anxiety disorder: a systematic review

    NARCIS (Netherlands)

    Noordik, Erik; van der Klink, Jac J. L.; Klingen, Elmer F.; Nieuwenhuijsen, Karen; van Dijk, Frank J. H.

    2010-01-01

    ABSTRACT: BACKGROUND: Anxiety disorders are associated with functional disability, sickness absence, and decreased productivity. Effective treatments of anxiety disorders can result in remission of symptoms. However the effects on work related outcomes are largely unknown. Exposure in vivo is

  10. Exposure-in-vivo containing interventions to improve work functioning of workers with anxiety disorder : a systematic review

    NARCIS (Netherlands)

    Noordik, Erik; van der Klink, Jac J. L.; Klingen, Elmer F.; Nieuwenhuijsen, Karen; van Dijk, Frank J. H.

    2010-01-01

    Background: Anxiety disorders are associated with functional disability, sickness absence, and decreased productivity. Effective treatments of anxiety disorders can result in remission of symptoms. However the effects on work related outcomes are largely unknown. Exposure in vivo is potentially well

  11. Channel length scaling and the impact of metal gate work function ...

    Indian Academy of Sciences (India)

    Further- more, quantum effects on the performance of DG-MOSFETs are addressed and discussed. We also study the influence of metal gate work function on the performance of nanoscale MOSFETs. We use a self-consistent Poisson–Schrödinger solver in two dimensions over the entire device. A good agreement with ...

  12. [State of the visual function in locomotive team personnel working in zones of radioactive pollution].

    Science.gov (United States)

    Sosnova, T L; Kudriashova, Zh M; Baranova, E L; Bukhareva, E A

    1995-01-01

    Professionally significant visual functions were examined in members of locomotive teams living and working in zones of radioactive pollution. Exposure to low-dose radiation was found to have an adverse effect on the status of visual analyzer, the degree of impairment being related to the level of radioactivity and age of the patient.

  13. Quantitative ionization energies and work functions of aqueous solutions.

    Science.gov (United States)

    Olivieri, Giorgia; Goel, Alok; Kleibert, Armin; Cvetko, Dean; Brown, Matthew A

    2016-10-26

    Despite the ubiquitous nature of aqueous solutions across the chemical, biological and environmental sciences our experimental understanding of their electronic structure is rudimentary-qualitative at best. One of the most basic and seemingly straightforward properties of aqueous solutions-ionization energies-are (qualitatively) tabulated at the water-air interface for a mere handful of solutes, and the manner in which these results are obtained assume the aqueous solutions behave like a gas in the photoelectron experiment (where the vacuum levels of the aqueous solution and of the photoelectron analyzer are equilibrated). Here we report the experimental measure of a sizeable offset (ca. 0.6 eV) between the vacuum levels of an aqueous solution (0.05 M NaCl) and that of our photoelectron analyzer, indicating a breakdown of the gas-like vacuum level alignment assumption for the aqueous solution. By quantifying the vacuum level offset as a function of solution chemical composition our measurements enable, for the first time, quantitative determination of ionization energies in liquid solutions. These results reveal that the ionization energy of liquid water is not independent of the chemical composition of the solution as is usually inferred in the literature, a finding that has important ramifications as measured ionization energies are frequently used to validate theoretical models that posses the ability to provide microscopic insight not directly available by experiment. Finally, we derive the work function, or the electrochemical potential of the aqueous solution and show that it too varies with the chemical composition of the solution.

  14. A functional magnetic resonance imaging study of working memory in youth after sports-related concussion: is it still working?

    Science.gov (United States)

    Keightley, Michelle L; Saluja, Rajeet Singh; Chen, Jen-Kai; Gagnon, Isabelle; Leonard, Gabriel; Petrides, Michael; Ptito, Alain

    2014-03-01

    Abstract In children, the importance of detecting deficits after mild traumatic brain injury (mTBI) or concussion has grown with the increasing popularity of leisure physical activities and contact sports. Whereas most postconcussive symptoms (PCS) are similar for children and adults, the breadth of consequences to children remains largely unknown. To investigate the effect of mTBI on brain function, we compared working memory performance and related brain activity using blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) in 15 concussed youths and 15 healthy age-matched control subjects. Neuropsychological tests, self-perceived PCS, and levels of anxiety and depression were also assessed. Our results showed that, behaviorally, concussed youths had significantly worse performances on the working memory tasks, as well as on the Rey figure delayed recall and verbal fluency. fMRI results revealed that, compared to healthy children, concussed youths had significantly reduced task-related activity in bilateral dorsolateral prefrontal cortex, left premotor cortex, supplementary motor area, and left superior parietal lobule during performance of verbal and nonverbal working memory tasks. Additionally, concussed youths also showed less activation than healthy controls in the dorsal anterior cingulate cortex, left thalamus, and left caudate nucleus during the nonverbal task. Regression analysis indicated that BOLD signal changes in bilateral dorsolateral prefrontal cortex were significantly correlated with performance such that greater activities in these regions, relative to the control condition, were associated with greater accuracy. Our findings confirmed functional alterations in brain activity after concussion in youths, a result similar to that observed in adults. However, significant differences were noted. In particular, the observation of reduced working memory accuracy suggests that youths may be unable to engage compensatory

  15. Peer Pressure in Work Teams : The effects of Inequity Aversion

    OpenAIRE

    Masclet, David

    2002-01-01

    Working Paper du GATE 2002-15; Many empirical studies have shed light on the efficiency of peer pressure. I propose here to model peer pressure by incorporating in the utility function self centered inequity aversion. I find that opportunity for sufficiently inequity averse players to punish their peers, is effective in inducing others to cooperate. At the equilibrium, all players cooperate and punish any shirker since punishing is a way to reduce inequity. Contrary, nobody cooperates without...

  16. Functional Brain Network Modularity Captures Inter- and Intra-Individual Variation in Working Memory Capacity

    Science.gov (United States)

    Stevens, Alexander A.; Tappon, Sarah C.; Garg, Arun; Fair, Damien A.

    2012-01-01

    Background Cognitive abilities, such as working memory, differ among people; however, individuals also vary in their own day-to-day cognitive performance. One potential source of cognitive variability may be fluctuations in the functional organization of neural systems. The degree to which the organization of these functional networks is optimized may relate to the effective cognitive functioning of the individual. Here we specifically examine how changes in the organization of large-scale networks measured via resting state functional connectivity MRI and graph theory track changes in working memory capacity. Methodology/Principal Findings Twenty-two participants performed a test of working memory capacity and then underwent resting-state fMRI. Seventeen subjects repeated the protocol three weeks later. We applied graph theoretic techniques to measure network organization on 34 brain regions of interest (ROI). Network modularity, which measures the level of integration and segregation across sub-networks, and small-worldness, which measures global network connection efficiency, both predicted individual differences in memory capacity; however, only modularity predicted intra-individual variation across the two sessions. Partial correlations controlling for the component of working memory that was stable across sessions revealed that modularity was almost entirely associated with the variability of working memory at each session. Analyses of specific sub-networks and individual circuits were unable to consistently account for working memory capacity variability. Conclusions/Significance The results suggest that the intrinsic functional organization of an a priori defined cognitive control network measured at rest provides substantial information about actual cognitive performance. The association of network modularity to the variability in an individual's working memory capacity suggests that the organization of this network into high connectivity within modules

  17. Functional brain network modularity captures inter- and intra-individual variation in working memory capacity.

    Directory of Open Access Journals (Sweden)

    Alexander A Stevens

    Full Text Available Cognitive abilities, such as working memory, differ among people; however, individuals also vary in their own day-to-day cognitive performance. One potential source of cognitive variability may be fluctuations in the functional organization of neural systems. The degree to which the organization of these functional networks is optimized may relate to the effective cognitive functioning of the individual. Here we specifically examine how changes in the organization of large-scale networks measured via resting state functional connectivity MRI and graph theory track changes in working memory capacity.Twenty-two participants performed a test of working memory capacity and then underwent resting-state fMRI. Seventeen subjects repeated the protocol three weeks later. We applied graph theoretic techniques to measure network organization on 34 brain regions of interest (ROI. Network modularity, which measures the level of integration and segregation across sub-networks, and small-worldness, which measures global network connection efficiency, both predicted individual differences in memory capacity; however, only modularity predicted intra-individual variation across the two sessions. Partial correlations controlling for the component of working memory that was stable across sessions revealed that modularity was almost entirely associated with the variability of working memory at each session. Analyses of specific sub-networks and individual circuits were unable to consistently account for working memory capacity variability.The results suggest that the intrinsic functional organization of an a priori defined cognitive control network measured at rest provides substantial information about actual cognitive performance. The association of network modularity to the variability in an individual's working memory capacity suggests that the organization of this network into high connectivity within modules and sparse connections between modules may reflect

  18. Simultaneous measurements of work function and H‒ density including caesiation of a converter surface

    Science.gov (United States)

    Cristofaro, S.; Friedl, R.; Fantz, U.

    2017-08-01

    Negative hydrogen ion sources rely on the surface conversion of neutral atomic hydrogen and positive hydrogen ions to H-. The efficiency of this process depends on the actual work function of the converter surface. By introducing caesium into the source the work function decreases, enhancing the negative ion yield. In order to study the impact of the work function on the H- surface production at similar conditions to the ones in ion sources for fusion devices like ITER and DEMO, fundamental investigations are performed in a flexible laboratory experiment. The work function of the converter surface can be absolutely measured by photoelectric effect, while a newly installed cavity ring-down spectroscopy system (CRDS) measures the H- density. The CRDS is firstly tested and characterized by investigations on H- volume production. Caesiation of a stainless steel sample is then performed in vacuum and the plasma effect on the Cs layer is investigated also for long plasma-on times. A minimum work function of (1.9±0.1) eV is reached after some minutes of plasma treatment, resulting in a reduction by a value of 0.8 eV compared to vacuum measurements. The H- density above the surface is (2.1±0.5)×1015 m-3. With further plasma exposure of the caesiated surface, the work function increases up to 3.75 eV, due to the impinging plasma particles which gradually remove the Cs layer. As a result, the H- density decreases by a factor of at least 2.

  19. Efficiency of initial presbyopia functional correction in visually intensive work persons

    Directory of Open Access Journals (Sweden)

    I. G. Ovechkin

    2015-01-01

    Full Text Available Aim: To study the efficacy of functional (physiotherapeutic stimulation of an eye in visually intensive work patients with the initial symptoms of presbyopia.Methods: 104 visually intensive work patients before and after complex physiotherapy (low-energy laser radiation, magnitotherapy, stimulation of accommodation were examined.Results: Physiotherapy improved near vision (by 0.16 RU on average and subjective psychophysiological status (by 11.8 % and reduced eye strain (by 2.1 times. Additionally, objective accommodography indices improved, brightness sensitivity thresholds decreased by 16.5 %, and psychological status improved by 18.2 %. These positive effects of physiotherapeutic stimulation enabled to delay eyeglasses prescription for 6 months in 76 % of patients and for 9 months in 42 % of patients.Conclusion: Functional (physiotherapeutic stimulation provides effective correction of initial presbyopia in visually intensive work persons.

  20. The Work Role Functioning Questionnaire v2.0 Showed Consistent Factor Structure Across Six Working Samples

    NARCIS (Netherlands)

    Abma, F.I.; Bultmann, U.; Amick III, B.C.; Arends, I.; Dorland, P.A.; Flach, P.A.; Klink, J.J.L van der; Ven H.A., van de; Bjørner, J.B.

    2017-01-01

    Objective The Work Role Functioning Questionnaire v2.0 (WRFQ) is an outcome measure linking a persons’ health to the ability to meet work demands in the twenty-first century. We aimed to examine the construct validity of the WRFQ in a heterogeneous set of working samples in the Netherlands with

  1. Working memory effects in speeded RSVP tasks.

    Science.gov (United States)

    Gil-Gómez de Liaño, Beatriz; Potter, Mary C; Rodríguez, Carmen

    2014-01-01

    The present paper examines the effects of memory contents and memory load in rapid serial visual presentation (RSVP) speeded tasks, trying to explain previous inconsistent results. We used a one target (Experiment 1) and a two-target (Experiment 2) RSVP task with a concurrent memory load of one or four items, in a dual-task paradigm. A relation between material in working memory and the target in the RSVP impaired the identification of the target. In Experiments 3 and 4, the single task was to determine whether any information in memory matched the target in the RSVP, while varying the memory load. A match was detected faster than a non-match, although only when there was some distance between targets in the RSVP (Experiment 4). The results suggest that memory contents automatically capture attention, slowing processing when the memory contents are irrelevant to the task, and speeding processing when they are relevant.

  2. Mindfulness, Authentic Functioning, and Work Engagement: A Growth Modeling Approach

    Science.gov (United States)

    Leroy, Hannes; Anseel, Frederik; Dimitrova, Nicoletta G.; Sels, Luc

    2013-01-01

    Previous research has demonstrated that mindfulness helps reduce symptoms of work stress but research has yet to clarify "whether" and "how" mindfulness is linked to work engagement. Using self-determination theory we hypothesize that mindfulness is positively related to work engagement and that this relationship can be better understood through…

  3. Functional connectivity among spikes in low dimensional space during working memory task in rat.

    Science.gov (United States)

    Ouyang, Mei; Li, Shuangyan; Tian, Xin

    2014-01-01

    Working memory (WM) is critically important in cognitive tasks. The functional connectivity has been a powerful tool for understanding the mechanism underlying the information processing during WM tasks. The aim of this study is to investigate how to effectively characterize the dynamic variations of the functional connectivity in low dimensional space among the principal components (PCs) which were extracted from the instantaneous firing rate series. Spikes were obtained from medial prefrontal cortex (mPFC) of rats with implanted microelectrode array and then transformed into continuous series via instantaneous firing rate method. Granger causality method is proposed to study the functional connectivity. Then three scalar metrics were applied to identify the changes of the reduced dimensionality functional network during working memory tasks: functional connectivity (GC), global efficiency (E) and casual density (CD). As a comparison, GC, E and CD were also calculated to describe the functional connectivity in the original space. The results showed that these network characteristics dynamically changed during the correct WM tasks. The measure values increased to maximum, and then decreased both in the original and in the reduced dimensionality. Besides, the feature values of the reduced dimensionality were significantly higher during the WM tasks than they were in the original space. These findings suggested that functional connectivity among the spikes varied dynamically during the WM tasks and could be described effectively in the low dimensional space.

  4. Functional connectivity among spikes in low dimensional space during working memory task in rat.

    Directory of Open Access Journals (Sweden)

    Mei Ouyang

    Full Text Available Working memory (WM is critically important in cognitive tasks. The functional connectivity has been a powerful tool for understanding the mechanism underlying the information processing during WM tasks. The aim of this study is to investigate how to effectively characterize the dynamic variations of the functional connectivity in low dimensional space among the principal components (PCs which were extracted from the instantaneous firing rate series. Spikes were obtained from medial prefrontal cortex (mPFC of rats with implanted microelectrode array and then transformed into continuous series via instantaneous firing rate method. Granger causality method is proposed to study the functional connectivity. Then three scalar metrics were applied to identify the changes of the reduced dimensionality functional network during working memory tasks: functional connectivity (GC, global efficiency (E and casual density (CD. As a comparison, GC, E and CD were also calculated to describe the functional connectivity in the original space. The results showed that these network characteristics dynamically changed during the correct WM tasks. The measure values increased to maximum, and then decreased both in the original and in the reduced dimensionality. Besides, the feature values of the reduced dimensionality were significantly higher during the WM tasks than they were in the original space. These findings suggested that functional connectivity among the spikes varied dynamically during the WM tasks and could be described effectively in the low dimensional space.

  5. Band alignment and effective work function of atomic-layer deposited VO{sub 2} and V{sub 2}O{sub 5} films on SiO{sub 2} and Al{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Cerbu, F.; Chou, H.S.; Afanas' ev, V.V.; Stesmans, A. [Department of Physics and Astronomy, University of Leuven (Belgium); Radu, I.P.; Martens, K.; Peter, A.P. [IMEC, Leuven (Belgium)

    2015-01-01

    The effective work function (EWF) and the energy position of the valence band in 20-40-nm thick VO{sub 2} and V{sub 2}O{sub 5} layers grown by atomic layer deposition (ALD) on top of insulating SiO{sub 2} and γ-Al{sub 2}O{sub 3} films were evaluated using the comparison between capacitance-voltage and internal photoemission measurements. From the capacitance measured at different temperatures on the metal-VO{sub 2}(V{sub 2}O{sub 5})-insulator-silicon and metal-insulator-silicon diodes we found that the both studied vanadium oxides have the same EWF as gold electrodes evaporated on the same oxides. This result is further collaborated by the internal photoemission experiments at the VO{sub 2}/SiO{sub 2} and V{sub 2}O{sub 5}/SiO{sub 2} interfaces which indicate the energy barrier between the top of the vanadium oxide valence band (in the insulating phase) and the insulator conduction band to be 4.1 ± 0.1 eV. Since the transition from the narrow-gap VO{sub 2} to the wide-gap V{sub 2}O{sub 5} oxide causes no change in the WF or in the photoemission threshold, we conclude that the ALD-grown VO{sub 2} in its insulating phase represents a a heavily-doped semiconductor which becomes metallic upon metal-insulator transition without significant EWF change. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. Acute glucocorticoid effects on the multicomponent model of working memory.

    Science.gov (United States)

    Vaz, Leonardo José; Pradella-Hallinan, Márcia; Bueno, Orlando Francisco Amodeo; Pompéia, Sabine

    2011-10-01

    In comparison with basal physiological levels, acute, high levels of cortisol affect learning and memory. Despite reports of cortisol-induced episodic memory effects, no study has used a comprehensive battery of tests to evaluate glucocorticoid effects on the multicomponent model of working memory. Here, we report the results of a double-blind, placebo-controlled, between-subjects study. Twenty healthy young men were randomly assigned to either acute cortisol (30 mg hydrocortisone) or placebo administration. Participants were subjected to an extensive cognitive test battery that evaluated all systems of the multicomponent model of working memory, including various executive domains (shifting, updating, inhibition, planning and access to long-term memory). Compared with placebo, hydrocortisone administration increased cortisol blood levels and impaired working memory in storage of multimodal information in the episodic buffer and maintenance/reverberation of information in the phonological loop. Hydrocortisone also decreased performance in planning and inhibition tasks, the latter having been explained by changes in storage of information in working memory. Thus, hydrocortisone acutely impairs various components of working memory, including executive functioning. This effect must be considered when administering similar drugs, which are widely used for the treatment of many clinical disorders. Copyright © 2011 John Wiley & Sons, Ltd.

  7. Effectiveness of work zone intelligent transportation systems.

    Science.gov (United States)

    2013-12-01

    In the last decade, Intelligent Transportation Systems (ITS) have increasingly been deployed in work zones by state departments of transportation. Also known as smart work zone systems they improve traffic operations and safety by providing real-time...

  8. Tuning the work function of stepped metal surfaces by adsorption of organic molecules.

    Science.gov (United States)

    Jiang, Yingda; Li, Jingtai; Su, Guirong; Ferri, Nicola; Liu, Wei; Tkatchenko, Alexandre

    2017-05-24

    Understanding the binding mechanisms for aromatic molecules on transition-metal surfaces, especially with defects such as vacancies, steps and kinks, is a major challenge in designing functional interfaces for organic devices. One important parameter in the performance of organic/inorganic devices is the barrier of charge carrier injection. In the case of a metallic electrode, tuning the electronic interface potential or the work function for electronic level alignment is crucial. Here, we use density-functional theory (DFT) calculations with van der Waals (vdW) interactions treated with both screened pairwise (vdW(surf)) and many-body dispersion (MBD) methods, to systematically study the interactions of benzene with a variety of stepped surfaces. Our calculations confirm the physisorptive character of Ag(2 1 1), Ag(5 3 3), Ag(3 2 2), Ag(7 5 5) and Ag(5 4 4) surfaces upon the adsorption of benzene. The MBD effects reduce the adsorption energies by about 0.15 eV per molecule compared to the results from the DFT  +  vdW(surf) method. In addition, we find that the higher the step density, the larger the reduction of the work function upon the adsorption of benzene. We also study the effect of vdW interactions on the electronic structure using a fully self-consistent implementation of the vdW(surf) method in the Kohn-Sham DFT framework. We find that the self-consistent vdW(surf) effects increase the work function due to the lowered Fermi level and the increased vacuum level. As a result, the benzene/Ag(2 1 1) system has the lowest work function (3.67 eV) among the five adsorption systems, significantly smaller than the work function of the clean Ag(1 1 1) surface (4.74 eV). Our results provide important insights into the stability and electronic properties of molecules adsorbed on stepped metal surfaces, which could help in designing more appropriate interfaces with low work functions for electron transfer.

  9. Tuning the work function of stepped metal surfaces by adsorption of organic molecules

    Science.gov (United States)

    Jiang, Yingda; Li, Jingtai; Su, Guirong; Ferri, Nicola; Liu, Wei; Tkatchenko, Alexandre

    2017-05-01

    Understanding the binding mechanisms for aromatic molecules on transition-metal surfaces, especially with defects such as vacancies, steps and kinks, is a major challenge in designing functional interfaces for organic devices. One important parameter in the performance of organic/inorganic devices is the barrier of charge carrier injection. In the case of a metallic electrode, tuning the electronic interface potential or the work function for electronic level alignment is crucial. Here, we use density-functional theory (DFT) calculations with van der Waals (vdW) interactions treated with both screened pairwise (vdWsurf) and many-body dispersion (MBD) methods, to systematically study the interactions of benzene with a variety of stepped surfaces. Our calculations confirm the physisorptive character of Ag(2 1 1), Ag(5 3 3), Ag(3 2 2), Ag(7 5 5) and Ag(5 4 4) surfaces upon the adsorption of benzene. The MBD effects reduce the adsorption energies by about 0.15 eV per molecule compared to the results from the DFT  +  vdWsurf method. In addition, we find that the higher the step density, the larger the reduction of the work function upon the adsorption of benzene. We also study the effect of vdW interactions on the electronic structure using a fully self-consistent implementation of the vdWsurf method in the Kohn-Sham DFT framework. We find that the self-consistent vdWsurf effects increase the work function due to the lowered Fermi level and the increased vacuum level. As a result, the benzene/Ag(2 1 1) system has the lowest work function (3.67 eV) among the five adsorption systems, significantly smaller than the work function of the clean Ag(1 1 1) surface (4.74 eV). Our results provide important insights into the stability and electronic properties of molecules adsorbed on stepped metal surfaces, which could help in designing more appropriate interfaces with low work functions for electron transfer.

  10. Spatial working memory in heavy cannabis users: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Kanayama, Gen; Rogowska, Jadwiga; Pope, Harrison G; Gruber, Staci A; Yurgelun-Todd, Deborah A

    2004-11-01

    Many neuropsychological studies have documented deficits in working memory among recent heavy cannabis users. However, little is known about the effects of cannabis on brain activity. We assessed brain function among recent heavy cannabis users while they performed a working memory task. Functional magnetic resonance imaging was used to examine brain activity in 12 long-term heavy cannabis users, 6-36 h after last use, and in 10 control subjects while they performed a spatial working memory task. Regional brain activation was analyzed and compared using statistical parametric mapping techniques. Compared with controls, cannabis users exhibited increased activation of brain regions typically used for spatial working memory tasks (such as prefrontal cortex and anterior cingulate). Users also recruited additional regions not typically used for spatial working memory (such as regions in the basal ganglia). These findings remained essentially unchanged when re-analyzed using subjects' ages as a covariate. Brain activation showed little or no significant correlation with subjects' years of education, verbal IQ, lifetime episodes of cannabis use, or urinary cannabinoid levels at the time of scanning. Recent cannabis users displayed greater and more widespread brain activation than normal subjects when attempting to perform a spatial working memory task. This observation suggests that recent cannabis users may experience subtle neurophysiological deficits, and that they compensate for these deficits by "working harder"-calling upon additional brain regions to meet the demands of the task.

  11. Nursing leadership and management effects work environments.

    Science.gov (United States)

    Tomey, Ann Marriner

    2009-01-01

    The aim of this literature search was to identify recent research related to nursing leadership and management effects on work environment using the 14 forces of magnetism. This article gives some historical perspective from the original 1983 American Academy of Nursing study through to the 2002 McClure and Hinshaw update to 2009 publications. Research publications were given a priority for references. The 14 forces of magnetism as identified by Unden and Monarch were: '1. Quality of leadership..., 2. Organizational structure..., 3. Management style..., 4. Personnel policies and programs..., 5. Professional models of care..., 6. Quality of care..., 7 Quality improvement..., 8. Consultation and resources..., 9. Autonomy..., 10. Community and the hospital..., 11. Nurse as teacher..., 12. Image of nursing..., 13. Interdisciplinary relationships... and 14. Professional development....'. Correlations have been found among positive workplace management initiatives, style of transformational leadership and participative management; patient-to-nurse ratios; education levels of nurses; quality of patient care, patient satisfaction, employee health and well-being programmes; nurse satisfaction and retention of nurses; healthy workplace environments and healthy patients and personnel. This article identifies some of the research that provides evidence for evidence-based nursing management and leadership practice.

  12. Momentary Work Happiness as a Function of Enduring Burnout and Work Engagement.

    Science.gov (United States)

    Bakker, Arnold B; Oerlemans, Wido G M

    2016-08-17

    The present study (N = 136) combined global measures with specific, experience-based measures to investigate how enduring job burnout and engagement influence the impact of daily work activities on momentary need satisfaction and happiness. We used the day reconstruction method (DRM) to ask employees from various occupations to reconstruct their working days. On the basis of employee work engagement and self-determination theories, we hypothesized that time spent on (a) core work tasks; (b) administrative work tasks; (c) client interactions; (d) interactions with colleagues; and (e) meetings would be negatively related to need satisfaction on the task level for employees high (vs. low) in enduring burnout; and positively related to need satisfaction on the task level for employees high (vs. low) in enduring work engagement. In addition, we predicted that psychological need satisfaction would mediate the relationships between time spent on work tasks and happiness during the tasks. The results of multilevel analyses largely supported these hypotheses. Our findings contribute to the literature by showing how those with high levels of burnout do not manage to satisfy their basic needs through their work, whereas those with high levels of work engagement satisfy their daily needs and stay happy.

  13. Meaningful work for a meaningful life? Work alienation and its effects in the work and the family context

    NARCIS (Netherlands)

    L.G. Tummers (Lars); L. den Dulk (Laura)

    2012-01-01

    textabstractAbstract. The notion of work alienation and its consequences has fascinated scholars and practitioners for a long time. But most research focused on passive performance indicators (such as job satisfaction), while the effects on work alienation on active performance (work effort) and

  14. Group Work: How to Use Groups Effectively

    Science.gov (United States)

    Burke, Alison

    2011-01-01

    Many students cringe and groan when told that they will need to work in a group. However, group work has been found to be good for students and good for teachers. Employers want college graduates to have developed teamwork skills. Additionally, students who participate in collaborative learning get better grades, are more satisfied with their…

  15. Alcohol effects on cardiac function.

    Science.gov (United States)

    Gardner, Jason D; Mouton, Alan J

    2015-04-01

    The consumption of ethanol can have both beneficial and detrimental effects on the function of the heart and cardiovascular system, depending on the amount consumed. Low-to-moderate amounts of ethanol intake are associated with improvements in cardiac function and vascular health. On the other hand, ethanol chronically consumed in large amounts acts as a toxin to the heart and vasculature. The cardiac injury produced by chronic alcohol abuse can progress to heart failure and eventual death. Furthermore, alcohol abuse may exacerbate preexisting heart conditions, such as hypertension and cardiomyopathy. This article focuses on the molecular mechanisms and pathophysiology of both the beneficial and detrimental cardiac effects of alcohol. © 2015 American Physiological Society.

  16. An extensive investigation of work function modulated trapezoidal recessed channel MOSFET

    Science.gov (United States)

    Lenka, Annada Shankar; Mishra, Sikha; Mishra, Satyaranjan; Bhanja, Urmila; Mishra, Guru Prasad

    2017-11-01

    The concept of silicon on insulator (SOI) and grooved gate help to lessen the short channel effects (SCEs). Again the work function modulation along the metal gate gives a better drain current due to the uniform electric field along the channel. So all these concepts are combined and used in the proposed MOSFET structure for more improved performance. In this work, trapezoidal recessed channel silicon on insulator (TRC-SOI) MOSFET and work function modulated trapezoidal recessed channel silicon on insulator (WFM-TRC-SOI) MOSFET are compared with DC and RF parameters and later linearity of both the devices is tested. An analytical model is formulated by using a 2-D Poisson's equation and develops a compact equation for threshold voltage using minimum surface potential. In this work we analyze the effect of negative junction depth and the corner angle on various device parameters such as minimum surface potential, sub-threshold slope (SS), drain induced barrier lowering (DIBL) and threshold voltage. The analysis interprets that the switching performance of WFM-TRC-SOI MOSFET surpasses TRC-SOI MOSFET in terms of high Ion/Ioff ratio and also the proposed structure can minimize the short channel effects (SCEs) in RF application. The validity of proposed model has been verified with simulation result performed on Sentaurus TCAD device simulator.

  17. Research Paper Working memory functioning in children with ...

    African Journals Online (AJOL)

    Objective: Children with attention-deficit/hyperactivity disorder (ADHD) often experience working memory difficulties. However, research findings are inconsistent, making it difficult to compare results across studies. There are several reasons for this inconsistency. Firstly, most studies make no distinction between ADHD ...

  18. Beyond Conflict: Functional Facets of the Work-Family Interplay

    Science.gov (United States)

    Wiese, Bettina S.; Seiger, Christine P.; Schmid, Christian M.; Freund, Alexandra M.

    2010-01-01

    The present paper deals with three positive facets of the work-family interplay, i.e., transfer of competencies, transfer of positive mood, and cross-domain compensation. The latter refers to the experience that engagement in one domain helps dealing with failures in the other domain. In two correlational studies (N[subscript 1] = 107 working…

  19. EFFECT OF SCHOOL CLIMATE, WORK STRESS AND WORK MOTIVATION ON THE PERFORMANCE OF TEACHER

    OpenAIRE

    Ramlani Lina Sinaulan

    2016-01-01

    Performance is a form of behavior of a person or organization with achievement orientation. The study results are known (a) the school climate affect performance of teachers, b) there is influence of work stress on teacher performance, (c) work motivation effect on teacher performance, d) school climate influence on job motivation of teachers, and (e) work stress effect on work motivation of teachers. Suggestions studies (a) improving teacher performance should the top priority schools in sch...

  20. Effect of yogic training on physiological variables in working women.

    Science.gov (United States)

    Kurwale, Manisha V; Gadkari, Jayeshree V

    2014-01-01

    Depression and anxiety in women sharply rising. Working women have high level of stress than non working women. Increasing amount of work stress at home and work place and its impact on family and home environment can be seen, which affect their emotional, psychological and physical health. The concept of yoga is helpful for reducing anxiety and improving cardiorespiratory parameters has created a great interest in the medical research field. The present study was conducted to assessing the effect of yogic exercises and meditation in working women. Yogic session was carried out for 16 weeks. Cardiorespiratory parameters (pulse rate, respiratory rate, blood pressure and breath holding time) were measured before and after yoga training. Stress was measured by anxiety score as an indicator of stress, also Visual reaction time as an indicator of cognitive function and finger dexterity score as an indicator of motor skills were measured before and after yoga training. Statistical analysis was done by paired 't' test. It was found that statistically significant improvement in cardiorespiratory parameters, anxiety score, visual reaction time and finger dexterity score (P meditation & relaxation technique in a sequence is the best available resource to meet the.present day needs of society.

  1. Serotonergic modulation in executive functioning: linking genetic variations to working memory performance.

    Science.gov (United States)

    Enge, Sören; Fleischhauer, Monika; Lesch, Klaus-Peter; Reif, Andreas; Strobel, Alexander

    2011-11-01

    Emerging evidence from studies using, for example, acute tryptophan depletion or investigating genetic variation of genes related to the serotonin signaling pathway suggest a role of serotonin in executive functions such as top-down attention, working memory and inhibitory control. In the current study, we aimed at extending this evidence by using the n-back task to examine working memory performance of 130 participants via behavioral and neurophysiological indices and by focusing on variations within genes encoding key regulators of the serotonergic system: the serotonin transporter gene-linked polymorphic region (5-HTTLPR) and a repeat polymorphism in the transcriptional control region of the monoamine-oxidase gene (MAOA-uVNTR). Because serotonin and norepinephrine systems have been shown to be structurally and functionally highly interrelated, we also examined a novel polymorphism in the promoter region of the norepinephrine transporter gene (NET -3081) in anticipation of epistatic effects. We found that carriers of 5-HTTLPR and MAOA-uVNTR alleles recently implicated in executive processing showed a more efficient executive control of working memory-related performance as evidenced by reaction time, error rate as well as N2 and P3b event-related potential measures. This impact was further supported by interactions with the NET polymorphism. Linking serotonergic influence to mechanisms of inhibitory response control implicated in working memory, our results provide further support for and add new evidence concerning the importance of serotonergic neuromodulation in executive functioning. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. A study of cardiopulmonary function and working capacity of ...

    African Journals Online (AJOL)

    Forced vital capacity (fvc, L/sec), forced expiratory volume (fev1, L/sec), fev1%, forced expiratory flow rate (fef 200—1200 ml,. L/sec), forced mid-expiratory flow rate (fmf 25—75 %, L/sec), peak expiratory flow rate (pefr, L/min), minute ventilation (ve, L/min), oxygen saturation of arterial blood (SaO2%), working capacity ...

  3. The Effects of Smoking Abstinence on Incentivized Spatial Working Memory.

    Science.gov (United States)

    Geier, Charles; Roberts, Nicole; Lydon-Staley, David

    2018-01-02

    Reward processing and working memory (WM) underlie value-based decision-making; consequently, joint examination of these systems may further our understanding of why smokers choose to smoke again following a quit attempt (relapse). While previous studies have demonstrated altered reward and WM function associated with nicotine exposure, little is known about the effects of abstinence on the joint function of these systems. The current study aims to address this gap. Eighteen daily smokers were tested on a monetarily incentivized memory guided saccade (MGS) task on two separate, counterbalanced occasions, an abstinent and a non-abstinent session. The MGS task is a widely used metric of spatial working memory and enables precise quantification of the effects of rewards and nicotine exposure on behavior. During the non-abstinent session, participants showed increased accuracy of the initial saccade towards the remembered target location on reward vs. neutral trials. Participants also showed increased accuracy of the final saccade towards the target, across incentive types, only during the non-abstinent condition. Our observation that rewards improve the accuracy of the initial memory guided saccade during the non-abstinent but not abstinent condition extends a growing literature indicating reduced motivation towards monetary rewards during abstinence. Further, differences in the accuracy of the final corrective saccade during the non-abstinent but not the abstinent condition suggests smoking abstinence-related effects on WM precision beyond those related to incentive motivation (e.g., sustained attention). This work extends our fundamental understanding of smoking's effects on core affective and cognitive processes.

  4. The effects of diabetes mellitus and hypertension on work productivity.

    Science.gov (United States)

    Krstović-Spremo, Vesna; Račić, Maja; Joksimović, Bojan N; Joksimović, Vedrana R

    2014-01-01

    The primary objective of this paper is to examine the impact of diabetes mellitus on the ability to work in patients with diabetes mellitus. The second objective of this paper is to examine the differences in the ability to work between patients with diabetes mellitus and patients with other chronic diseases, such as hypertension. A study was conducted in 10 family medicine practices from two primary health care centers, Pale and East Sarajevo, in the period between July 2009 and May 2010, utilising a retrospective medical records review and a cross sectional survey. The outcomes used to portray respondent's health status included functional measures and ability to work. Functional measures were analyzed using SF-36 and a general questionnaire. Absenteeism and productivity loss were retrospectively analyzed for the past ten years from a regional sick-leave database and the administrative records of the Commission for the assessment of work capacity for the Pension and Disability Insurance Fund of the Republika Srpska respectively. Out of the total number of patients with diabetes, 24.6% had some form of disability. A statistically significant difference was found between the two groups; patients with diabetes mellitus were much more likely to have problems meeting the required standards at the workplace due to emotional and physical health issues compared to hypertensive patients. Diabetes mellitus appears to reduce an individual's ability to work in comparison to patients with hypertension. There is a need to set up a diabetes mellitus prevention program and to develop and implement effective targeted intervention to help workers to manage their disease better. Copyright © 2014 by Academy of Sciences and Arts of Bosnia and Herzegovina.

  5. The moderating effect of work-time influence on the effect of shift work: a prospective cohort study

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Kirsten; Garde, Anne Helene; Albertsen, Karen

    2011-01-01

    To investigate whether work-time influence moderated the effect of shift work on psychological well-being measured as vitality, mental health, somatic stress symptoms, and disturbed sleep.......To investigate whether work-time influence moderated the effect of shift work on psychological well-being measured as vitality, mental health, somatic stress symptoms, and disturbed sleep....

  6. Predictors of impaired work functioning in employees with major depression in remission

    NARCIS (Netherlands)

    Vries, G. de; Koeter, M.W.; Nieuwenhuijsen, K.; Hees, H.L.; Schene, A.H.

    2015-01-01

    OBJECTIVES: This study aims to (i) assess work functioning in employees returning to work with a major depression in remission, (ii) study the predictors of impaired work functioning. METHODS: Participants diagnosed with major depressive disorder (MDD), on long term sick leave (mean 27 weeks) and

  7. Predictors of impaired work functioning in employees with major depression in remission

    NARCIS (Netherlands)

    de Vries, Gabe; Koeter, Maarten W. J.; Nieuwenhuijsen, Karen; Hees, Hiske L.; Schene, Aart H.

    2015-01-01

    This study aims to (i) assess work functioning in employees returning to work with a major depression in remission, (ii) study the predictors of impaired work functioning. Participants diagnosed with major depressive disorder (MDD), on long term sick leave (mean 27 weeks) and treated in a

  8. Leaders in hospital-based social work: the roles and functions of directors of social work in the case management model.

    Science.gov (United States)

    Guo, Kristina L; Company, Jennifer D

    2007-01-01

    The purpose of this research is to provide an overview of the management skills and competencies required by a director of social work as they perform their multiple roles and functions in order to effectively manage a medical social work team to better serve the needs of patients through the new hospital-based case management model. This is a conceptual paper that reviews the literature on managerial roles, management functions, and skills and competencies of directors of social work. Management frameworks that are applicable under the case management model are discussed. Interviews with five directors of social work and their perceptions are described. Managing a department that is going through continuous changes is often difficult. This paper has practical implications for general health care managers and specifically, directors of social work, to develop skills and gain competencies to be successful in today's evolving health care environment This research also has practical implications for social workers to gain insight into productive and effective ways to collaborate with members of an interdisciplinary team. This paper is original and of value to those working in social work and in the health care field to develop their skills and competencies as they perform new roles and functions in the complex health care environment.

  9. Accumulated Effects of Work under Heat Stress

    Science.gov (United States)

    1980-04-01

    in duplicates. The total protetig serum concentrations were determined by the Biuret method (107). Albumin was determined with Bromcresol Green (Sigma...requirements for the degree of /_Doctor,:of Philosophy. AV{ Acces•ion For CONTENTS u::...:" - - _:,-.. • Page INTRODUCTION 1 METHODS 7 .- 5 I. Studies of a...34limitirg- factor" to work in a hot environment. (2 5 METHODS The study was conducted on the employees of a plant locatad in Sdom ("Sdom") and a plart in

  10. The Work Role Functioning Questionnaire v2.0 Showed Consistent Factor Structure Across Six Working Samples

    DEFF Research Database (Denmark)

    Abma, Femke I.; Bültmann, Ute; Amick, Benjamin C.

    2017-01-01

    Objective: The Work Role Functioning Questionnaire v2.0 (WRFQ) is an outcome measure linking a persons’ health to the ability to meet work demands in the twenty-first century. We aimed to examine the construct validity of the WRFQ in a heterogeneous set of working samples in the Netherlands...... with mixed clinical conditions and job types to evaluate the comparability of the scale structure. Methods: Confirmatory factor and multi-group analyses were conducted in six cross-sectional working samples (total N = 2433) to evaluate and compare a five-factor model structure of the WRFQ (work scheduling....... Therefore subscale scores are recommended to compare across different clinical and working samples....

  11. Characterizing Cognitive Aging of Working Memory and Executive Function in Animal Models

    Directory of Open Access Journals (Sweden)

    Jennifer Lynn Bizon

    2012-09-01

    Full Text Available Executive functions supported by prefrontal cortical systems provide essential control and planning mechanisms to guide goal-directed behavior. As such, age-related alterations in executive functions can mediate profound and widespread deficits on a diverse array of neurocognitive processes. Many of the critical neuroanatomical and functional characteristics of prefrontal cortex are preserved in rodents, allowing for meaningful cross-species comparisons relevant to the study of cognitive aging. In particular, as rodents lend themselves to genetic, cellular and biochemical approaches, rodent models of executive function stand to significantly contribute to our understanding of the critical neurobiological mechanisms that mediate decline of executive processes across the lifespan. Moreover, rodent analogues of executive functions that decline in human aging represent an essential component of a targeted, rational approach for developing and testing effective treatment and prevention therapies for age-related cognitive decline. This paper reviews behavioral approaches used to study executive function in rodents, with a focus on those assays that share a foundation in the psychological and neuroanatomical constructs important for human aging. A particular emphasis is placed on behavioral approaches used to assess working memory and cognitive flexibility, which are sensitive to decline with age across species and for which strong rodent models currently exist. In addition, other approaches in rodent behavior that have potential for providing analogues to functions that reliably decline to human aging (e.g., information processing speed are discussed.

  12. Training working memory in kindergarten children: Effects on working memory and early numeracy

    NARCIS (Netherlands)

    Kroesbergen, E.H.; Noordende, J.E. van 't; Kolkman, M.E.

    2014-01-01

    This study investigated the relationship between working memory and early numeracy. It aimed toexplore the possibility of training young children's working memory and to investigate the effects ofsuch training both on working memory and on the specific domain of early numerical skills. Measuresof

  13. The double whammy of a work handicap (differential) effects of health on working conditions and outcomes.

    Science.gov (United States)

    Steenbeek, Romy; Giesen, Femke B M; Ybema, Jan Fekke

    2009-08-01

    To determine the effect of health on working conditions and outcomes. Data were collected in the longitudinal Study on Health at Work (n = 1597 employees), using multiple regression analyses and focusing on three groups of employees: 1) healthy, 2) chronic health complaints without a work handicap, and 3) chronic health complaints with a work handicap. 1) Employees with a work handicap experienced less favorable working conditions and outcomes than other employees. 2) Employees with a work handicap experienced less favorable working conditions and outcomes over time. 3) Employees with chronic health complaints were more vulnerable to the influence of working conditions on outcomes, whereas employees with a work handicap, unexpectedly, benefited from high work pressure and low autonomy. 1) Employees with a work handicap differ considerably from employees with chronic health complaints. 2) Employees with a work handicap drift into less favorable working conditions and outcomes. 3) Healthy employees, employees with chronic health complaints, and employees with a work handicap, all are vulnerable to different working conditions.

  14. Effects of new ways of working on work hours and work location, health and job-related outcomes

    NARCIS (Netherlands)

    Nijp, Hylco H.; Beckers, Debby G. J.; van de Voorde, F.C.; Geurts, Sabine A. E.; Kompier, Michiel A. J.

    2016-01-01

    New ways of working (NWW) is a type of work organization that is characterized by temporal and spatial flexibility, often combined with extensive use of information and communication technologies (ICT) and performance-based management. In a three-wave intervention study, we examined the effects of

  15. PASSENGER CAR USAGE FOR COMMUTING TO WORK AS A FUNCTION OF LIMITED STAY AT CAR PARKS

    Directory of Open Access Journals (Sweden)

    Valentina Basarić

    2013-07-01

    Full Text Available The analysis of the experiences in European cities, following the implementation of different transport policy measures, has led to a conclusion that parking policy measures have the dominant effect on the choice of private car as a mode of transport. This effect is the greatest for the commutes to work, characterized by the longest duration of parking space occupancy. Given the aforementioned experiences in developed European cities, the main aim of the study presented here was the determination of a relationship between limiting the duration of parking space occupancy in the Novi Sad city centre and the transport participants’ decision whether or not to use passenger car to commute to work. Based on the established interdependence between these parameters, we developed a mathematical model for calculating a number of expected car (commuting journeys that terminate in the city centre as a function of limited duration of parking space occupancy.  

  16. Processing speed and visuospatial executive function predict visual working memory ability in older adults.

    Science.gov (United States)

    Brown, Louise A; Brockmole, James R; Gow, Alan J; Deary, Ian J

    2012-01-01

    BACKGROUND/STUDY CONTEXT: Visual working memory (VWM) has been shown to be particularly age sensitive. Determining which measures share variance with this cognitive ability in older adults may help to elucidate the key factors underlying the effects of aging. Predictors of VWM (measured by a modified Visual Patterns Test) were investigated in a subsample (N = 44, mean age = 73) of older adults from the Lothian Birth Cohort 1936 (LBC1936; Deary et al., 2007 , BMC Geriatrics, 7, 28). Childhood intelligence (Moray House Test) and contemporaneous measures of processing speed (four-choice reaction time), executive function (verbal fluency; block design), and spatial working memory (backward spatial span), were assessed as potential predictors. All contemporaneous measures except verbal fluency were significantly associated with VWM, and processing speed had the largest effect size (r = -.53, p material are also important.

  17. Functional MRI in Awake Dogs Predicts Suitability for Assistance Work

    Science.gov (United States)

    Berns, Gregory S.; Brooks, Andrew M.; Spivak, Mark; Levy, Kerinne

    2017-03-01

    The overall goal of this work was to measure the efficacy of fMRI for predicting whether a dog would be a successful service dog. The training and imaging were performed in 49 dogs entering service training at 17-21 months of age. 33 dogs completed service training and were matched with a person, while 10 were released for behavioral reasons (4 were selected as breeders and 2 were released for medical reasons.) After 2 months of training, fMRI responses were measured while each dog observed hand signals indicating either reward or no reward and given by both a familiar handler and a stranger. Using anatomically defined ROIs in the caudate, amygdala, and visual cortex, we developed a classifier based on the dogs’ subsequent training outcomes. The classifier had a positive predictive value of 94% and a negative predictive value of 67%. The area under the ROC curve was 0.91 (0.80 with 4-fold cross-validation, P = 0.01), indicating a significant predictive capability. The magnitude of response in the caudate was positively correlated with a successful outcome, while the response in the amygdala depended on the interaction with the visual cortex during the stranger condition and was negatively correlated with outcome (higher being associated with failure). These results suggest that, as indexed by caudate activity, successful service dogs generalize associations to hand signals regardless who gives them but without excessive arousal as measured in the amygdala.

  18. Functional capacity and work ability in patients with chronic musculoskeletal pain

    NARCIS (Netherlands)

    van der Meer, Suzan

    2014-01-01

    Patients suffering from chronic low back pain (CLBP) and whiplash associated disorders (WAD) may experience many problems, including in work. Work ability is considered a balance between work demands and personal resources. Functional Capacity Evaluations (FCE) can be used to measure aspects of work

  19. The Effect of Multitasking to Faculty Members' Academic Works

    Science.gov (United States)

    Baran, Bahar

    2013-01-01

    Faculty members in higher education institutions which technology produced in and used actively try to overcome simultaneous one more works because of their intensive works and responsibilities. This study associated simultaneously doing one more academic works to multitasking. Multitasking may have a detrimental effect on academic works since it…

  20. Large work function difference driven electron transfer from electrides to single-walled carbon nanotubes

    KAUST Repository

    Menamparambath, Mini Mol

    2014-06-23

    A difference in work function plays a key role in charge transfer between two materials. Inorganic electrides provide a unique opportunity for electron transfer since interstitial anionic electrons result in a very low work function of 2.4-2.6 eV. Here we investigated charge transfer between two different types of electrides, [Ca2N]+·e- and [Ca 24Al28O64]4+·4e-, and single-walled carbon nanotubes (SWNTs) with a work function of 4.73-5.05 eV. [Ca2N]+·e- with open 2-dimensional electron layers was more effective in donating electrons to SWNTs than closed cage structured [Ca24Al28O64] 4+·4e- due to the higher electron concentration (1.3 × 1022 cm-3) and mobility (∼200 cm 2 V-1 s-1 at RT). A non-covalent conjugation enhanced near-infrared fluorescence of SWNTs as high as 52%. The field emission current density of electride-SWNT-silver paste dramatically increased by a factor of 46000 (14.8 mA cm-2) at 2 V μm-1 (3.5 wt% [Ca2N]+·e-) with a turn-on voltage of 0.85 V μm-1. This journal is © the Partner Organisations 2014.

  1. A Normative Model of Work Team Effectiveness

    Science.gov (United States)

    1983-11-01

    dramas are played out, from political intrigues to romantic encounters. Our present focus on task effectiveness does not deny the multiple purposes...attributes of group members). 5 Research on process-outcome relationships has emphasized the impact of group interaction on the attitudes, beliefs, and...orocal effects on each other. This model suggests that group interaction does mediate the impact of input conditions--but also that performance outcomes

  2. Effects of new ways of working on work hours and work location, health and job-related outcomes.

    Science.gov (United States)

    Nijp, Hylco H; Beckers, Debby G J; van de Voorde, Karina; Geurts, Sabine A E; Kompier, Michiel A J

    2016-01-01

    New ways of working (NWW) is a type of work organization that is characterized by temporal and spatial flexibility, often combined with extensive use of information and communication technologies (ICT) and performance-based management. In a three-wave intervention study, we examined the effects of NWW on both the organization of work (changes in control over time and place of work; working hours and work location; and other key job characteristics), and on employees' outcomes (work-nonwork balance; health and well-being; and job-related outcomes). We applied a quasi-experimental design within a large Dutch financial company (N = 2,912). We studied an intervention group (n = 2,391) and made comparisons with a reference group (n = 521). There were three study waves: (i) one/two months before, and (ii) 4 months and (iii) 10 months after implementation of NWW. Repeated measures analyses of covariance (involving 361 participants from the intervention group and 80 participants from the reference group) showed a large and significant shift from hours worked at the office to hours worked at home after implementation of NWW. Accordingly, commuting time was reduced. Employees remained working on week days and during day time. Psychosocial work-characteristics, work-nonwork balance, stress, fatigue, and job-related outcomes remained favourable and largely unaffected, but the health score in the intervention group decreased (medium effect). These findings suggest that the implementation of NWW does not necessarily lead to changes in psychosocial work characteristics, well-being or job-related outcomes.

  3. Effects of modafinil on working memory processes in humans.

    Science.gov (United States)

    Müller, Ulrich; Steffenhagen, Nikolai; Regenthal, Ralf; Bublak, Peter

    2004-12-01

    Modafinil is a well-tolerated psychostimulant drug with low addictive potential that is used to treat patients with narcolepsy or attention deficit disorders and to enhance vigilance in sleep-deprived military personal. So far, understanding of the cognitive enhancing effects of modafinil and the relevant neurobiological mechanisms are incomplete. The aim of this study was to investigate the effects of modafinil on working memory processes in humans and how they are related to noradrenergic stimulation of the prefrontal cortex. Sixteen healthy volunteers (aged 20-29 years) received either modafinil 200 mg or placebo using a double blind crossover design. Two computerized working memory tasks were administered, a numeric manipulation task that requires short-term maintenance of digit-sequences and different degrees of manipulation as well as delayed matching task that assesses maintenance of visuo-spatial information over varying delay lengths. The battery was supplemented by standardized paper pencil tasks of attentional functions. Modafinil significantly reduced error rates in the long delay condition of the visuo-spatial task and in the manipulation conditions, but not in the maintenance condition of the numeric task. Analyses of reaction times showed no speed-accuracy trade-off. Attentional control tasks (letter cancellation, trail-making, catch trials) were not affected by modafinil. In healthy volunteers without sleep deprivation modafinil has subtle stimulating effects on maintenance and manipulation processes in relatively difficult and monotonous working memory tasks, especially in lower performing subjects. Overlapping attentional and working memory processes have to be considered when studying the noradrenergic modulation of the prefrontal cortex.

  4. Introducing Trimming and Function Ranking to SolidWorks based on Function Analysis

    NARCIS (Netherlands)

    Chechurin, L.S.; Wits, Wessel Willems; Bakker, Hans M.; Vaneker, Thomas H.J.

    2015-01-01

    TRIZ based Function Analysis models existing products based on functional interactions between product parts. Such a function model description is the ideal starting point for product innovation. Design engineers can apply (TRIZ) methods such as trimming and function ranking to this function model

  5. Introducing trimming and function ranking to Solid Works based on function analysis

    NARCIS (Netherlands)

    Chechurin, Leonid S.; Wits, Wessel Willems; Bakker, Hans M.; Cascini, G.; Vaneker, Thomas H.J.

    2011-01-01

    TRIZ based Function Analysis models existing products based on functional interactions between product parts. Such a function model description is the ideal starting point for product innovation. Design engineers can apply (TRIZ) methods such as trimming and function ranking to this function model

  6. Interaction effect of work excitement and work frustration on the professional commitment of nurses in Taiwan.

    Science.gov (United States)

    Chang, Yuan-Ping; Wang, Hsiu-Hung; Huang, Shan; Wang, Huang-I

    2014-03-01

    The current shortage of professional nurses in Taiwan both undermines hospital quality of care and raises hospitals' human resource management costs. Few studies have concurrently investigated the interaction effect between professional commitment and, respectively, the positive and negative work attitudes of nurses. Results of this investigation may help improve strategies designed to raise nurse retention rates. This study used the interaction effects of work excitement and work frustration to assess their influence on the professional commitment of nurses. This study was conducted at one hospital in southern Taiwan and used a cross-sectional design with self-administrated questionnaires. Seven hundred thirty-five nurses completed and submitted valid questionnaires (valid response rate: 68.5%). Exploratory and confirmatory factor analysis confirmed the reliability and validity of the three measurement models of work excitement, work frustration, and professional commitment. Correlation and hierarchical regression analysis verified the direct and interaction effects with the correlations among the three measured variables. Work frustration was higher than work excitement among participants (M = 2.72, SD = 0.71 vs. M = 2.26, SD = 0.62). The mean participant score for professional commitment was 2.72 (SD = 0.45) on a 4-point Likert scale. There was a significant and positive correlation between work excitement and professional commitment and a significant and negative correlation between work frustration and professional commitment. High work frustration had a negative effect on professional commitment, whereas high work excitement had a higher positive effect on professional commitment. The two-way interaction between work excitement and frustration was statistically significant in explaining the effects of professional commitment (p Nurses often work in conditions that are highly frustrating. Although work excitement has been shown as having a greater influence on

  7. A universal method to produce low-work function electrodes for organic electronics

    National Research Council Canada - National Science Library

    Zhou, Yinhua; Fuentes-Hernandez, Canek; Shim, Jaewon; Meyer, Jens; Giordano, Anthony J; Li, Hong; Winget, Paul; Papadopoulos, Theodoros; Cheun, Hyeunseok; Kim, Jungbae; Fenoll, Mathieu; Dindar, Amir; Haske, Wojciech; Najafabadi, Ehsan; Khan, Talha M; Sojoudi, Hossein; Barlow, Stephen; Graham, Samuel; Brédas, Jean-Luc; Marder, Seth R; Kahn, Antoine; Kippelen, Bernard

    2012-01-01

    .... We show that surface modifiers based on polymers containing simple aliphatic amine groups substantially reduce the work function of conductors including metals, transparent conductive metal oxides...

  8. Neuropsychological function and employment status in a welfare-to-work sample.

    Science.gov (United States)

    Gorske, Tad T; Daley, Dennis C; Yenerall, Eric; Morrow, Lisa A

    2006-01-01

    Since 1996, individuals who participate in welfare programs are mandated to find employment. Welfare recipients may have difficulty transitioning to the workforce due to impairments in psychosocial functioning. Examples include mental health and substance use disorders, medical problems, academic and learning difficulties, and lack of resources such as childcare and transportation. An area unexplored as a potential barrier is cognitive functioning as influencing recipient's ability to transition into the workforce. This is important because many Welfare to Work (WtW) recipients have personal risk factors related to impaired cognitive ability. We evaluated the relationship between demographics, cognitive functioning, and substance abuse severity in a group of 180 WtW recipients in order to assess predictors of employment impairment. No relationship was found between employment functioning and alcohol use, drug use, or psychiatric impairment. However neuropsychological test results demonstrate that WtW study participants with lower scores on tests of general intelligence are more impaired in their employment functioning. General intelligence emerged as the best predictor of employment functioning. The results have implications for identifying individuals at risk for unsuccessful transition into the workforce and for the development of effective vocational rehabilitation strategies.

  9. The Effects of Poetry and Lyrics on Work Values.

    Science.gov (United States)

    Markert, Louis F.; Healy, Charles C.

    1983-01-01

    Discusses a study that tested whether guided examination of selected poems and songs would increase proclivity for work and appreciation of work values. Compared the effectiveness of the infusion intervention with a more traditional career planning treatment. (JOW)

  10. SPIROMETRIC EVALUATION OF LUNG FUNCTION OF COAL WORKERS WORKING AT MACH (BOLAN DISTRICT)

    OpenAIRE

    Ghulam Sarwar, Muhammad Younis, Shafi Muhammad, Tanzeel Ahmed*, Muhammad Siddique, Bashir Ahmed, Munir Ahmed, Jahanzaib

    2017-01-01

    To evaluate the coal dust effect on lung function among coal workers and non-coal workers. This was case-control study. The 144 male coal workers and non-coal workers, 20-50 years more than one year of working skill were selected. Study was carried out in the Mach, Bolan district in Balochistan, Pakistan. The Spirometer and selfdesigned survey form were used. The interview was accompanied and information was documented in the survey form and Spirometry was done for coal workers and non-coal w...

  11. Shift work effects on serial PEF measurements for occupational asthma.

    Science.gov (United States)

    Moore, V C; Jaakkola, M S; Burge, C B S G; Pantin, C F A; Robertson, A S; Burge, P S

    2012-10-01

    Diurnal variation (DV) affects lung function but the changes are thought to be related to sleep patterns rather than time of day. When diagnosing occupational asthma (OA), serial peak expiratory flow (PEF) measurements are the recommended first line investigation, but could be confounded by shift work. The aim of the study was to investigate the effects of shift work on PEF measurements used for diagnosing OA. PEF records containing more than one shift pattern with ≥ 4 days per shift were identified. OA diagnosis was based on an Oasys-2 score ≥ 2.51 and non-OA on having an alternative clinical diagnosis and Oasys-2 score PEF DV and cross-shift PEF changes were calculated for each shift. Records from 123 workers with OA and 69 without OA satisfied inclusion criteria. In the OA group, PEF declined more on afternoon and night shifts than days (P PEF increased more on day shifts (mean + 25 l/min) than afternoon or night shifts (+1 l/min) (P PEF responses between work and rest show small differences according to shift type. The ABC score has a high sensitivity and specificity for all shifts; differences in DV have lower specificity.

  12. Effects of extended work shifts and shift work on patient safety, productivity, and employee health.

    Science.gov (United States)

    Keller, Simone M

    2009-12-01

    It is estimated 1.3 million health care errors occur each year and of those errors 48,000 to 98,000 result in the deaths of patients (Barger et al., 2006). Errors occur for a variety of reasons, including the effects of extended work hours and shift work. The need for around-the-clock staff coverage has resulted in creative ways to maintain quality patient care, keep health care errors or adverse events to a minimum, and still meet the needs of the organization. One way organizations have attempted to alleviate staff shortages is to create extended work shifts. Instead of the standard 8-hour shift, workers are now working 10, 12, 16, or more hours to provide continuous patient care. Although literature does support these staffing patterns, it cannot be denied that shifts beyond the traditional 8 hours increase staff fatigue, health care errors, and adverse events and outcomes and decrease alertness and productivity. This article includes a review of current literature on shift work, the definition of shift work, error rates and adverse outcomes related to shift work, health effects on shift workers, shift work effects on older workers, recommended optimal shift length, positive and negative effects of shift work on the shift worker, hazards associated with driving after extended shifts, and implications for occupational health nurses. Copyright 2009, SLACK Incorporated.

  13. Effective visual working memory capacity: an emergent effect from the neural dynamics in an attractor network.

    Directory of Open Access Journals (Sweden)

    Laura Dempere-Marco

    Full Text Available The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1 the presence of a visually salient item reduces the number of items that can be held in working memory, and 2 visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC in contrast to the maximal upper capacity limit only reached under ideal conditions.

  14. Effective Visual Working Memory Capacity: An Emergent Effect from the Neural Dynamics in an Attractor Network

    Science.gov (United States)

    Dempere-Marco, Laura; Melcher, David P.; Deco, Gustavo

    2012-01-01

    The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions. PMID:22952608

  15. Effective visual working memory capacity: an emergent effect from the neural dynamics in an attractor network.

    Science.gov (United States)

    Dempere-Marco, Laura; Melcher, David P; Deco, Gustavo

    2012-01-01

    The study of working memory capacity is of outmost importance in cognitive psychology as working memory is at the basis of general cognitive function. Although the working memory capacity limit has been thoroughly studied, its origin still remains a matter of strong debate. Only recently has the role of visual saliency in modulating working memory storage capacity been assessed experimentally and proved to provide valuable insights into working memory function. In the computational arena, attractor networks have successfully accounted for psychophysical and neurophysiological data in numerous working memory tasks given their ability to produce a sustained elevated firing rate during a delay period. Here we investigate the mechanisms underlying working memory capacity by means of a biophysically-realistic attractor network with spiking neurons while accounting for two recent experimental observations: 1) the presence of a visually salient item reduces the number of items that can be held in working memory, and 2) visually salient items are commonly kept in memory at the cost of not keeping as many non-salient items. Our model suggests that working memory capacity is determined by two fundamental processes: encoding of visual items into working memory and maintenance of the encoded items upon their removal from the visual display. While maintenance critically depends on the constraints that lateral inhibition imposes to the mnemonic activity, encoding is limited by the ability of the stimulated neural assemblies to reach a sufficiently high level of excitation, a process governed by the dynamics of competition and cooperation among neuronal pools. Encoding is therefore contingent upon the visual working memory task and has led us to introduce the concept of effective working memory capacity (eWMC) in contrast to the maximal upper capacity limit only reached under ideal conditions.

  16. The effects of nationality differences and work stressors on work adjustment for foreign nurse aides

    Directory of Open Access Journals (Sweden)

    Yang Hsieh

    2011-08-01

    Full Text Available Abstract Background The main purpose of this study was to discuss the nationality differences of foreign nurse aides and the effect of work stressors influencing work adjustment. And of helping them adapt to Taiwanese society, we summarized the difficulties that foreign nurse aides face in Taiwan. Methods The subjects included 80 foreign nurse aides from the Philippines, Indonesia, and Vietnam who worked in long-term care facilities in Tao Yuan County. We recruited volunteers at the participating facilities to complete the anonymous questionnaires. The return rate of the questionnaire was 88.75%. The validated instruments of Hershenson's (1981 and Schaefer and Moos (1993 were adopted to measure work stressors and work adjustment, respectively. A forward-backward translation process was used in this study. Results Indonesian foreign nurse aides respect their work, and are better workers than Vietnamese and Filipino nurse aids in many respects, which shows how the nationality of the foreign nurse aides might affect work adjustment. The stress created from patient care tasks influenced the foreign nurse aides' personal relationships at work and also affected their attitude when they performed their tasks. In addition, pressure from their supervisors might have affected their work skills, work habits, personal relationships, self-concepts or work attitudes. Moreover, a heavy workload and improper scheduling might have affected the personal relationships and work attitudes of the foreign nurse aides. It was found that work stressors had a significant correlation with work adjustment. Conclusions The results of the present study indicate that training programs are important factors for work adjustment among foreign nurse aides. Furthermore, celebration and leisure activities could be provided to release them from work stressors. More effort should be put into improving the working environment, namely providing a more supportive and enriching

  17. The Formation of Effective Work Groups within an FE Classroom

    Science.gov (United States)

    Russell, Megan

    2010-01-01

    Fascinated by the diversity of composition in effective work groups in Further Education (FE) classrooms, I studied group formation and composition in level 3 Biology classes over an academic year. Using information from the class teacher, observers and students, the importance of effective work groups (defining effectiveness in terms of…

  18. Brain Training Game Boosts Executive Functions, Working Memory and Processing Speed in the Young Adults: A Randomized Controlled Trial

    OpenAIRE

    Rui Nouchi; Yasuyuki Taki; Hikaru Takeuchi; Hiroshi Hashizume; Takayuki Nozawa; Toshimune Kambara; Atsushi Sekiguchi; Carlos Makoto Miyauchi; Yuka Kotozaki; Haruka Nouchi; Ryuta Kawashima

    2013-01-01

    BACKGROUND: Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults. METHODS: We conducted a double-blind (de facto masking) randomized controlled trial using a p...

  19. The effects of emotional intelligence on counterproductive work behaviors

    OpenAIRE

    Seyed Morteza Emami

    2014-01-01

    This paper presents an empirical investigation to study the effects of emotional intelligence on counterproductive work behavior. The study uses a questionnaire for measuring the effects of emotional intelligence, which consists of four components including self-awareness, self-control, self-motivation and empathy. In addition, the study uses another questionnaire to measure the effects of counterproductive work behavior. The study has accomplished among full time employees who work for Indus...

  20. Reliability and Validity of the Work Role Functioning Questionnaire (Spanish Version)

    NARCIS (Netherlands)

    Ramada, Jose M.; Serra, Consol; Amick, Benjamin C.; Abma, Femke I.; Castano, Juan R.; Pidemunt, Gemma; Bultmann, Ute; Delclos, George L.

    2014-01-01

    Purpose Recently, the cross-cultural adaptation of the Work Role Functioning Questionnaire to Spanish was carried out, achieving satisfactory psychometric properties. Now we examined the reliability and validity of the adapted [Work role functioning questionnaire-Spanish version (WRFQ-SpV)] in a

  1. Work function anisotropy and surface stability of half-metallic CrO(2)

    NARCIS (Netherlands)

    Attema, J. J.; Uijttewaal, M. A.; de Wijs, G. A.; de Groot, R. A.

    Insight in the interplay between work function and stability is important for many areas of physics. In this paper, we calculate the anisotropy in the work function and the surface stability of CrO(2), a prototype half-metal, and find an anisotropy of 3.8 eV. An earlier model for the relation

  2. Working memory in attention deficit/hyperactivity disorder is characterized by a lack of specialization of brain function.

    Directory of Open Access Journals (Sweden)

    Catherine Fassbender

    Full Text Available Working memory impairments are frequent in Attention Deficit/Hyperactivity Disorder (ADHD and create problems along numerous functional dimensions. The present study utilized the Visual Serial Addition Task (VSAT and functional magnetic resonance imaging (fMRI to explore working memory processes in thirteen typically developing (TD control and thirteen children with ADHD, Combined type. Analysis of Variance (ANOVA was used to examine both main effects and interactions. Working memory-specific activity was found in TD children in the bilateral prefrontal cortex. In contrast the within-group map in ADHD did not reveal any working-memory specific regions. Main effects of condition suggested that the right middle frontal gyrus (BA6 and the right precuneus were engaged by both groups during working memory processing. Group differences were driven by significantly greater, non-working memory-specific, activation in the ADHD relative to TD group in the bilateral insula extending into basal ganglia and the medial prefrontal cortex. A region of interest analysis revealed a region in left middle frontal gyrus that was more active during working memory in TD controls. Thus, only the TD group appeared to display working memory-modulated brain activation. In conclusion, children with ADHD demonstrated reduced working memory task specific brain activation in comparison to their peers. These data suggest inefficiency in functional recruitment by individuals with ADHD represented by a poor match between task demands and appropriate levels of brain activity.

  3. Working memory in attention deficit/hyperactivity disorder is characterized by a lack of specialization of brain function.

    Science.gov (United States)

    Fassbender, Catherine; Schweitzer, Julie B; Cortes, Carlos R; Tagamets, Malle A; Windsor, T Andrew; Reeves, Gloria M; Gullapalli, Rao

    2011-01-01

    Working memory impairments are frequent in Attention Deficit/Hyperactivity Disorder (ADHD) and create problems along numerous functional dimensions. The present study utilized the Visual Serial Addition Task (VSAT) and functional magnetic resonance imaging (fMRI) to explore working memory processes in thirteen typically developing (TD) control and thirteen children with ADHD, Combined type. Analysis of Variance (ANOVA) was used to examine both main effects and interactions. Working memory-specific activity was found in TD children in the bilateral prefrontal cortex. In contrast the within-group map in ADHD did not reveal any working-memory specific regions. Main effects of condition suggested that the right middle frontal gyrus (BA6) and the right precuneus were engaged by both groups during working memory processing. Group differences were driven by significantly greater, non-working memory-specific, activation in the ADHD relative to TD group in the bilateral insula extending into basal ganglia and the medial prefrontal cortex. A region of interest analysis revealed a region in left middle frontal gyrus that was more active during working memory in TD controls. Thus, only the TD group appeared to display working memory-modulated brain activation. In conclusion, children with ADHD demonstrated reduced working memory task specific brain activation in comparison to their peers. These data suggest inefficiency in functional recruitment by individuals with ADHD represented by a poor match between task demands and appropriate levels of brain activity.

  4. Working memory capacity and the spacing effect in cued recall.

    Science.gov (United States)

    Delaney, Peter F; Godbole, Namrata R; Holden, Latasha R; Chang, Yoojin

    2017-12-11

    Spacing repetitions typically improves memory (the spacing effect). In three cued recall experiments, we explored the relationship between working memory capacity and the spacing effect. People with higher working memory capacity are more accurate on memory tasks that require retrieval relative to people with lower working memory capacity. The experiments used different retention intervals and lags between repetitions, but were otherwise similar. Working memory capacity and spacing of repetitions both improved memory in most of conditions, but they did not interact, suggesting additive effects. The results are consistent with the ACT-R model's predictions, and with a study-phase recognition process underpinning the spacing effect in cued recall.

  5. Lung Function Impact from Working in the Pre-Revolution Libyan Quarry Industry

    Directory of Open Access Journals (Sweden)

    Marwan M. Draid

    2015-05-01

    Full Text Available The purpose of this study was to determine the lung impact from working within the Libyan quarry industry, and if the length of work impacted the degree of degradation. Eighty three workers from eight silica quarries in the Nafusa Mountains of Libya opted to participate. These quarries were working the upper cretaceous geological structure. Eighty-five individuals who lived in Gharyan City with no affiliation to quarry operations participated as controls. Spirometry variables evaluated were Forced Vital Capacity (FVC, Forced Expiratory Volume at 1.0 second (FEV1, FVC/FEV1 and Peak Expiratory Flow (PEF. Control and exposed groups had no differences in terms of height, weight, or smoking status (p = 0.18, 0.20, 0.98, respectively. Prior to adjustment for other variables, FVC, FEV1, and PEF are all significantly lower in the exposed group (p = 0.003, 0.009, 0.03, respectively. After adjustment for age, height, weight, and smoking status, there remain significant differences between the control and exposed groups for FVC, FEV1, and PEF. This analysis demonstrated that exposure to quarry dust has a detrimental effect on lung function, and that pre-revolution Libyan quarry workers were being exposed. This study shows that any exposure is harmful, as the reduction in lung function was not significantly associated with years of exposure.

  6. Reduction of the Work Function of Gold by N-Heterocyclic Carbenes

    KAUST Repository

    Kim, Hye Kyung

    2017-04-12

    N-Heterocyclic carbenes (NHCs) bind strongly to gold and other metals. This work experimentally probes the effect of NHCs on the work function (WF) of gold for the first time, theoretically analyzes the origin of this effect, and examines the effectiveness of NHC-modified gold as an electron-injecting electrode. UV photoelectron spectroscopy shows the WF of planar gold is reduced by nearly 2 eV to values of 3.3–3.5 eV. This effect is seen for NHCs with various heterocyclic cores, and with either small or large N,N′-substituents. DFT calculations indicate the WF reduction results from both the interface dipole formed between the NHC and the gold and from the NHC molecular dipole. For N,N′-diisopropyl-NHCs, an important contributor to the former is charge transfer associated with coordination of the carbene carbon atom to gold. In contrast, the carbene carbon of N,N′-2,6-diisopropylphenyl-NHCs is not covalently bound to gold, resulting in a lower interface dipole; however, a larger molecular dipole partially compensates for this. Single-layer C60 diodes with NHC-modified gold as the bottom electrode demonstrate high rectification ratios and show that these electrodes can act as effective electron-injecting contacts, suggesting they may be useful for a variety of materials applications.

  7. Shift Work Disorder and Mental and Physical Effects of Shift Work

    Directory of Open Access Journals (Sweden)

    Pinar Guzel Ozdemir

    2018-03-01

    Full Text Available With the growing prevalence of shift work all over the the world, the relationship between the daily lives of irregular lifestyles and rhythms is being investigated for those working as shift workers and their families. The effect of shift work on physical and mental health is a very important field of research in recent years. The onset and persistence of medical complications in shift workers includes impaired synchronization between work schedule rhythms and circadian clock. In this context, studies have been carried out showing the increased risk of sleep-wake disorders, gastrointestinal problems, and cardiovascular diseases. There is little information about the actual frequency, effect on health and treatment of shift work disorder, known as circadian rhythm sleep disorder. Shift work disorder includes insomnia and/or excessive sleepiness related with the work schedule. The aim of this rewiev, mentioning about the physical and mental effects of shift work, and to provide information about the diagnosis, clinic and treatment methods of shift-work disorder.

  8. The double whammy of a work handicap (differential) effects of health on working conditions and outcomes

    NARCIS (Netherlands)

    Steenbeek, R.; Giesen, F.B.M.; Ybema, J.F.

    2009-01-01

    OBJECTIVE: To determine the effect of health on working conditions and outcomes. METHODS: Data were collected in the longitudinal Study on Health at Work (n = 1597 employees), using multiple regression analyses and focusing on three groups of employees: 1) healthy, 2) chronic health complaints

  9. Functional Impairments and Work-Related Outcomes in Breast Cancer Survivors: A Systematic Review

    NARCIS (Netherlands)

    Bijker, R.; Duijts, Saskia; Smith, S.N.; de Wildt- Liesveld, R.; Anema, Johannes R.; Regeer, B.J.

    2017-01-01

    Purpose Work participation after breast cancer treatment is generally negatively affected. Occupational health professionals might improve work-related outcomes by bridging the gap between sick-listed employees' levels of functioning and work demands. To aid them in this task, this review explored

  10. Working Memory Functioning in Children with Learning Disorders and Specific Language Impairment

    Science.gov (United States)

    Schuchardt, Kirsten; Bockmann, Ann-Katrin; Bornemann, Galina; Maehler, Claudia

    2013-01-01

    Purpose: On the basis of Baddeley's working memory model (1986), we examined working memory functioning in children with learning disorders with and without specific language impairment (SLI). We pursued the question whether children with learning disorders exhibit similar working memory deficits as children with additional SLI. Method: In…

  11. A Career Ladder's Effect on Teacher Career and Work Attitudes.

    Science.gov (United States)

    Hart, Ann Weaver

    1987-01-01

    A career ladder affecting the work structure and career opportunities of teachers was studied to determine effects on teacher attitudes. Responses of 389 elementary through high school teachers to career ladder work efforts, work of schools, peer supervision, and career growth opportunities and stability were affected by the design. (TJH)

  12. Spatial Working Memory Effects in Early Visual Cortex

    Science.gov (United States)

    Munneke, Jaap; Heslenfeld, Dirk J.; Theeuwes, Jan

    2010-01-01

    The present study investigated how spatial working memory recruits early visual cortex. Participants were required to maintain a location in working memory while changes in blood oxygen level dependent (BOLD) signals were measured during the retention interval in which no visual stimulation was present. We show working memory effects during the…

  13. Differential Age Effects on Spatial and Visual Working Memory

    Science.gov (United States)

    Oosterman, Joukje M.; Morel, Sascha; Meijer, Lisette; Buvens, Cleo; Kessels, Roy P. C.; Postma, Albert

    2011-01-01

    The present study was intended to compare age effects on visual and spatial working memory by using two versions of the same task that differed only in presentation mode. The working memory task contained both a simultaneous and a sequential presentation mode condition, reflecting, respectively, visual and spatial working memory processes. Young…

  14. Work, social support and leisure protect the elderly from functional loss: EPIDOSO study.

    Science.gov (United States)

    d'Orsi, Eleonora; Xavier, André Junqueira; Ramos, Luiz Roberto

    2011-08-01

    To identify risk factors for functional capacity loss in elderly people. Epidoso (Epidemiology of the Elderly) cohort study with elderly people living in São Paulo (Southeastern Brazil). A total of 326 participants in the first interview (1991-1992) who were independent or had mild dependence (one or two activities of daily living) were selected. Those who presented functional loss in the second (1994-1995) or third interviews (1998-1999) were compared to those who did not present it. The incidence of functional loss was calculated according to sociodemographic variables, life habits, cognitive status, morbidity, hospitalization, self-rated health, tooth loss, social support and leisure activities. Crude and adjusted relative risks with 95% confidence intervals were estimated through bivariate and multiple analyses with Poisson regression. The criterion for the inclusion of the variables in the model was p 0.10. The incidence of functional loss was 17.8% (13.6; 21.9). The risk factors in the final model were: age group 70-74 years RR=1.9 (0.9;3.9); age group 75-79 years RR=2.8 (1.4;5.5); age group 80 years or older RR=5.4 (3.0;9.6); score in the mini-mental state examination work RR=0.3 (0.1;1.0); monthly relationship with friends RR=0.5 (0.3;0.8); watching TV RR=0.5 (0.3;0.9); and handcrafting RR=0.7 (0.4;1.0). The prevention of functional loss should include adequate control of chronic diseases, like hypertension, asthma and diabetes, as well as cognitive stimulation. Work, leisure and relationships with friends should be valued due to their protective effect.

  15. Employment Effects of educational measures for work-injured people

    DEFF Research Database (Denmark)

    Bach, Henning Bjerregaard; Datta Gupta, Nabanita; Høgelund, Jan

    Vocational rehabilitation in the form of education is the cornerstone of governmental rehabilitation programs for the work-disabled in many countries. Merging a 2004 Danish survey to register information from the Danish National Board of Industrial Injuries, we assess the employment effects...... employers a partial wage subsidy for disabled workers’ wages, by distinguishing between education effects of a return to wage-subsidized work versus a return to ordinary work. Unlike previous studies, we find a positive impact of educational measures on the probability of returning to work for the work...

  16. Differential Effects of Alcohol Consumption Behaviours on Working Memory Processes

    OpenAIRE

    Shaunak Sanjay Deshpande

    2015-01-01

    Alcohol exposure in a clinical population impairs working memory. In order to establish the effects of alcohol on working memory in typical young adults, this study looked at their alcohol consumption behaviours and how they predict working memory. A battery of cognitive tasks and a recreational drug use questionnaire assessed working memory and alcohol consumption of 100 participants. The results revealed that alcohol abstinence predicted set-shifting, verbal executive, phonological loop, sp...

  17. Factors predicting work outcome in Japanese patients with schizophrenia: role of multiple functioning levels

    Directory of Open Access Journals (Sweden)

    Chika Sumiyoshi

    2015-09-01

    Full Text Available Functional outcomes in individuals with schizophrenia suggest recovery of cognitive, everyday, and social functioning. Specifically improvement of work status is considered to be most important for their independent living and self-efficacy. The main purposes of the present study were 1 to identify which outcome factors predict occupational functioning, quantified as work hours, and 2 to provide cut-offs on the scales for those factors to attain better work status. Forty-five Japanese patients with schizophrenia and 111 healthy controls entered the study. Cognition, capacity for everyday activities, and social functioning were assessed by the Japanese versions of the MATRICS Cognitive Consensus Battery (MCCB, the UCSD Performance-based Skills Assessment-Brief (UPSA-B, and the Social Functioning Scale Individuals’ version modified for the MATRICS-PASS (Modified SFS for PASS, respectively. Potential factors for work outcome were estimated by multiple linear regression analyses (predicting work hours directly and a multiple logistic regression analyses (predicting dichotomized work status based on work hours. ROC curve analyses were performed to determine cut-off points for differentiating between the better- and poor work status. The results showed that a cognitive component, comprising visual/verbal learning and emotional management, and a social functioning component, comprising independent living and vocational functioning, were potential factors for predicting work hours/status. Cut-off points obtained in ROC analyses indicated that 60–70% achievements on the measures of those factors were expected to maintain the better work status. Our findings suggest that improvement on specific aspects of cognitive and social functioning are important for work outcome in patients with schizophrenia.

  18. Imaging phonological similarity effects on verbal working memory.

    Science.gov (United States)

    Sweet, Lawrence H; Paskavitz, James F; Haley, Andreana P; Gunstad, John J; Mulligan, Richard C; Nyalakanti, Prashanth K; Cohen, Ronald A

    2008-03-07

    Studies of verbal working memory (VWM) report that performance declines as the phonemic similarity of stimuli increases. To determine how phonological similarity affects brain function during VWM, "standard" and "similarity" versions of the 2-Back task were presented to 34 healthy participants during functional magnetic resonance imaging (FMRI). Letter consonants presented during similarity blocks rhymed, while consonants did not rhyme during standard blocks. Empirical ROIs were identified from significant 2-Back-related activity observed during either condition. A priori ROIs were selected from functional neuroimaging literature on phonological processing. Although VWM-related activity was not modulated by similarity in any of four regions recruited (dorsolateral prefrontal, posterior parietal, anterior insular, and supplementary motor cortices), four of five regions of deactivation exhibited significantly greater deactivation during the similarity compared to the standard condition (posterior cingulate, paracentral lobule, posterior insula, and parahippocampal gyrus). In a priori phonological processing-related ROIs, similarity did not affect observed increases in activity (supplementary motor area, Broca's area, and cerebellum), while two of the three regions exhibiting decreased activity (near Wernicke's area and Heschel's Gyrus) also exhibited more deactivation during similarity. Accuracy was lower during the similarity 2-Back, positively related to activity within recruited VWM-related ROIs, and inversely related to activity in regions of VWM-related deactivation. Based on known functions of these ROIs, we conclude that language, audition, and self-reflection processes may disengage during phonological interference, while activity levels are maintained in regions recruited during VWM processing. Similarity effects likely include suspension of attention to unrelated and distracting processes to improve concentration.

  19. Practice on conflict tasks promotes executive function of working memory in the elderly.

    Science.gov (United States)

    Osaka, Mariko; Yaoi, Ken; Otsuka, Yuki; Katsuhara, Maya; Osaka, Naoyuki

    2012-07-15

    Effects of practice on a conflict task in elderly individuals are examined with a focus on its impact on executive function in working memory. During a short-term practice period, healthy elderly participants practiced switching attention using a Stroop task that involved a conflict between a task relevant stimulus and an irrelevant stimulus. To explore neural substrates underlying practice effects, two working memory tasks were used: a focus reading span test (F-RST) and a non-focus reading span test (NF-RST); the NF-RST test demanded greater switching attention due to a conflict between the relevant task stimulus and an irrelevant task stimulus, thus requiring an attention switch from the latter to the former. Following the Stroop task practice, fMRI data showed that participants who had engaged in practice had significant increases in activation in the anterior cingulate cortex (ACC), the left inferior parietal lobule (IPL), the left dorsolateral prefrontal cortex (DLPFC) and the precuneus regions during the NF-RST. By contrast, a control group, which did not practice, showed no significant increases in these regions. Results suggest that practice on conflict tasks in elderly individuals activated regions related to conflict perceiving and attention switching regions as well as attention-maintenance regions thereby improving performance on tasks requiring a high degree of attention control of working memory. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Pharmacologic Effects on Mitochondrial Function

    Science.gov (United States)

    Cohen, Bruce H.

    2010-01-01

    The vast majority of energy necessary for cellular function is produced in mitochondria. Free-radical production and apoptosis are other critical mitochondrial functions. The complex structure, electrochemical properties of the inner mitochondrial membrane (IMM), and genetic control from both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) are…

  1. Cluster analysis differentiates high and low community functioning in schizophrenia: Subgroups differ on working memory but not other neurocognitive domains.

    Science.gov (United States)

    Alden, Eva C; Cobia, Derin J; Reilly, James L; Smith, Matthew J

    2015-10-01

    Schizophrenia is characterized by impairment in multiple aspects of community functioning. Available literature suggests that community functioning may be enhanced through cognitive remediation, however, evidence is limited regarding whether specific neurocognitive domains may be treatment targets. We characterized schizophrenia subjects based on their level of community functioning through cluster analysis in an effort to identify whether specific neurocognitive domains were associated with variation in functioning. Schizophrenia (SCZ, n=60) and control (CON, n=45) subjects completed a functional capacity task, social competence role-play, functional attainment interview, and a neuropsychological battery. Multiple cluster analytic techniques were used on the measures of functioning in the schizophrenia subjects to generate functionally-defined subgroups. MANOVA evaluated between-group differences in neurocognition. The cluster analysis revealed two distinct groups, consisting of 36 SCZ characterized by high levels of community functioning (HF-SCZ) and 24 SCZ with low levels of community functioning (LF-SCZ). There was a main group effect for neurocognitive performance (pcluster analysis classified schizophrenia subjects in HF-SCZ and LF-SCZ using a multidimensional assessment of community functioning. Moreover, HF-SCZ demonstrated rather preserved verbal working memory relative to LF-SCZ. The results suggest that verbal working memory may play a critical role in community functioning, and is a potential cognitive treatment target for schizophrenia subjects. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Does living and working in a hot environment induce clinically relevant changes in immune function and voluntary force production capacity?

    Science.gov (United States)

    Knez, Wade; Girard, Olivier; Racinais, Sebastien; Walsh, Andrew; Gaoua, Nadia; Grantham, Justin

    2014-01-01

    This study investigated the effect of living (summer vs. winter) and working (morning vs. afternoon) in a hot environment on markers of immune function and forearm strength. Thirty-one healthy male gas field employees were screened before (between 05:30 and 07:00) and after their working day (between 15:30 and 17:00) during both seasons. Body core temperature and physical activity were recorded throughout the working days. The hot condition (i.e. summer) led a higher (p≤0.05) average body core temperature (~37.2 vs. ~37.4 °C) but reduced physical activity (-14.8%) during the work-shift. Our data showed an increase (p≤0.05) in lymphocyte and monocyte counts in the summer. Additionally, work-shift resulted in significant (p≤0.001) changes in leukocytes, lymphocytes and monocytes independently of the environment. Handgrip (p=0.069) and pinch (p=0.077) forces tended to be reduced from pre-to post-work, while only force produced during handgrip manoeuvres was significantly reduced (p≤0.05) during the hot compared to the temperate season. No interactions were observed between the environment and work-shift for any marker of immune function or forearm strength. In summary, working and living in hot conditions impact on markers of immune function and work capacity; however by self-regulating energy expenditure, immune markers remained in a healthy reference range.

  3. The associations between menstrual function and life style/working conditions among nurses in Taiwan.

    Science.gov (United States)

    Chung, Fen-Fang; Yao, Chuan-Chiang Chou; Wan, Gwo-Hwa

    2005-03-01

    This study was aimed at understanding the relationship among menstrual pattern, dysmenorrhea, life style and working conditions in nurses. The nurses were randomly selected from a medical center in Northern Taiwan. Each subject completed daily records including life and working conditions during the study period. The study showed that there were statistically significant differences in work years, daily working hours and type of work shift among nurses that worked at different units in the hospital. In the perceived regular cycle group, nurses that worked the night shift only exhibited the shortest menstrual cycles, less than 25 d. There was a significant difference (pstress) and working factors (such as work years, perceived work satisfaction and perceived work stress) were not significantly related to menstrual cycle regularity. In addition, 30% of the nurses complained of dysmenorrhea. Some factors including age, marital status and perceived life satisfaction were significantly related to dysmenorrhea. However, other life factors (such as passive tobacco smoke exposure, smoking, coffee, alcohol, cold drink habits, exercise and perceived life stress) and working factors (such as working places, type of work shift, daily work hours, perceived work satisfaction and perceived work stress) showed no correlation with dysmenorrhea. This study indicates that women should pay attention to their menstrual function and dysmenorrhea phenomenon.

  4. Effects of the Indianapolis Vocational Intervention Program (IVIP) on defeatist beliefs, work motivation, and work outcomes in serious mental illness.

    Science.gov (United States)

    Mervis, Joshua E; Fiszdon, Joanna M; Lysaker, Paul H; Nienow, Tasha M; Mathews, Laura; Wardwell, Patricia; Petrik, Tammy; Thime, Warren; Choi, Jimmy

    2017-04-01

    Defeatist beliefs and amotivation are prominent obstacles in vocational rehabilitation for people with serious mental illnesses (SMI). The CBT-based Indianapolis Vocational Intervention Program (IVIP) was specifically designed to reduce defeatist beliefs related to work functioning. In the current study, we examined the impact of IVIP on defeatist beliefs and motivation for work, hypothesizing that IVIP would be associated with a reduction in defeatist beliefs and greater motivation for work. We also examined the effects of IVIP on these variables as well as work outcomes during a 12-month follow-up. Participants with SMI (n=64) enrolled in a four-month work therapy program were randomized to IVIP or a support therapy group (SG). Assessments were conducted at baseline, post-treatment (4months), and follow-up (1year). Compared to those in SG condition, individuals randomized to IVIP condition reported greater reductions in defeatist beliefs and greater motivation for work at follow-up, along with greater supported employment retention rates. Specifically treating and targeting negative expectations for work therapy improves outcomes, even once active supports of the IVIP program and work therapy are withdrawn. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Assessment of the lung function status of the goldsmiths working in an unorganized sector of India

    Directory of Open Access Journals (Sweden)

    Subhashis Sahu

    2013-01-01

    Full Text Available Context: Exposure to various types of fumes and gases are very common in Jewelery industries. No Report is available regarding the effects of those fumes and gases on the respiratory functions of the goldsmiths. Due to lack of proper monitoring of the workplace environments in these unorganized sectors, workers get very much affected by the occupational exposures to those irritants. Aims: The present study aimed to investigate whether the occupational exposures to fumes and gases might alter the lung functions of the goldsmiths. Materials and Methods: A total of 118 goldsmiths and 66 unexposed control subjects were taken randomly for the study. The goldsmiths were further classified in 3 groups according to duration (year of exposures in the work environment, ETA 1 (less than 5 years, ETA 2 (more than 5 years but less than 10 years, and ETA 3 (more than 10 years. Peak expiratory flow rates (PEFR, forced vital capacity (FVC, and forced expiratory flow rates of different intervals (FEF 25% , FEF 50% , FEF 75% , FEF 25-75% were measured using computerized Spirometer (Maestros Mediline, India. The statistical analyses were carried out using Minitab software version 3. Results: Lung functions of the goldsmiths significantly (P < 0.01 decreased from that of the control group. Inter-group comparison also showed the deteriorations of lung functions was associated with exposure time, and more exposed workers had significantly less (P < 0.01 efficiencies of lung functions. Conclusions: Workplace fumes and gases were responsible for deterioration of the lung function status of the goldsmiths.

  6. Reflection on teaching effective social work practice for working with Muslim communities

    Directory of Open Access Journals (Sweden)

    Khadija Khaja

    2008-09-01

    Full Text Available In many academic departments like social work, psychology, and psychiatry there is a growing consensus that teachers need to instruct students to be culturally competent especially if they are going to be effective helpers with diverse populations. Multicultural instructional counseling methods are imperative if we are to ensure that our students of counseling are well prepared to work with diverse families, particularly those from Muslim backgrounds. In this narrative the author writes about the challenges of teaching non-Muslim students effective counseling techniques with Muslim families. Culturally innovative teaching methods are illustrated to facilitate students’ learning how to be effective counselors with Muslim communities.

  7. Work Function Tuning in Sub-20nm Titanium Nitride (TiN) Metal Gate: Mechanism and Engineering

    KAUST Repository

    Hasan, Mehdi

    2011-07-01

    burden of complex integration and gate stack etch; and finally it shows that in a low thermal budget flow, it is more effective to achieve higher work function.

  8. Effects of work environment on patient and nurse outcomes.

    Science.gov (United States)

    Copanitsanou, Panagiota; Fotos, Nikolaos; Brokalaki, Hero

    2017-02-09

    Several parameters of the nurse's work environment lead to fewer patient complications and lower nurse burnout. The aim of this systematic review was the analysis of research data related to the effect of nurses' work environments on outcomes for both patients and nurses. Medline was searched by using keywords: 'working conditions', 'work environment', 'nurses', 'nursing staff', 'patients', 'outcomes'. In total, 10 studies were included, of which 4 were cross-sectional and the remaining were descriptive correlational studies. Patients who were hospitalised in units with good work environments for the nurses were more satisfied with the nursing care than the patients in units with poor work environments. Nurses who perceived their work environment to be good experienced higher job satisfaction and lower rates of burnout syndrome. A good work environment constitutes a determinant factor for high care quality and, at the same time, relates to improved outcomes for the nurses.

  9. Effects of a Flexibility/Support Intervention on Work Performance.

    Science.gov (United States)

    Bray, Jeremy W; Hinde, Jesse M; Kaiser, David J; Mills, Michael J; Karuntzos, Georgia T; Genadek, Katie R; Kelly, Erin L; Kossek, Ellen E; Hurtado, David A

    2017-01-01

    To estimate the effects of a workplace initiative to reduce work-family conflict on employee performance. A group-randomized multisite controlled experimental study with longitudinal follow-up. An information technology firm. Employees randomized to the intervention (n = 348) and control condition (n = 345). An intervention, "Start. Transform. Achieve. Results." to enhance employees' control over their work time, to increase supervisors' support for this change, and to increase employees' and supervisors' focus on results. We estimated the effect of the intervention on 9 self-reported employee performance measures using a difference-in-differences approach with generalized linear mixed models. Performance measures included actual and expected hours worked, absenteeism, and presenteeism. This study found little evidence that an intervention targeting work-family conflict affected employee performance. The only significant effect of the intervention was an approximately 1-hour reduction in expected work hours. After Bonferroni correction, the intervention effect is marginally insignificant at 6 months and marginally significant at 12 and 18 months. The intervention reduced expected working time by 1 hour per week; effects on most other employee self-reported performance measures were statistically insignificant. When coupled with the other positive wellness and firm outcomes, this intervention may be useful for improving employee perceptions of increased access to personal time or personal wellness without sacrificing performance. The null effects on performance provide countervailing evidence to recent negative press on work-family and flex work initiatives.

  10. Understanding the corrosion behavior of isomorphous Cu–Ni alloy from its electron work function

    Energy Technology Data Exchange (ETDEWEB)

    Huang, X.C.; Lu, H.; Li, D.Y., E-mail: dongyang.li@ualberta.ca

    2016-04-15

    The electrode potential or galvanic series is usually used to reflect the nobility of metals and semi-metals. However, this potential is environment-dependent and the intrinsic nobility of a metal is ultimately governed by its electron stability, which can be represented by the electron work function (EWF). This article reports our studies on the corrosion behavior of isomorphous Cu–Ni alloy in HCl and NaCl solutions, respectively. It was demonstrated that the EWF of the alloy increased as the Ni concentration was increased, so did the corrosion resistance in the acidic solution. In the sodium chloride solution, however, the trend was reversed due to adsorption, hydrolysis and the formation of oxide scale on Cu-rich samples, which more or less prevented them from further corrosion in this solution. In order to confirm this, corrosive wear tests were performed to analyze the performance of the alloy when the effect of oxide scale was eliminated or minimized by the mechanical action. - Highlights: • Increasing %Ni resulted in higher overall electron work function of Cu–Ni alloy. • Higher EWF corresponded to higher resistance to corrosion in a HCl solution. • Trend was reversed in a NaCl solution due to the formation of oxide scale. • During slurry-jet tests, alloys with higher EWFs performed better.

  11. A Conceptual Foundation for Measures of Physical Function and Behavioral Health Function for Social Security Work Disability Evaluation

    Science.gov (United States)

    Marfeo, Elizabeth E.; Haley, Stephen M.; Jette, Alan M.; Eisen, Susan V.; Ni, Pengsheng; Bogusz, Kara; Meterko, Mark; McDonough, Christine M.; Chan, Leighton; Brandt, Diane E.; Rasch, Elizabeth K.

    2014-01-01

    Physical and mental impairments represent the two largest health condition categories for which workers receive Social Security disability benefits. Comprehensive assessment of physical and mental impairments should include aspects beyond medical conditions such as a person’s underlying capabilities as well as activity demands relevant to the context of work. The objective of this paper is to describe the initial conceptual stages of developing new measurement instruments of behavioral health and physical functioning relevant for Social Security work disability evaluation purposes. To outline a clear conceptualization of the constructs to be measured, two content models were developed using structured and informal qualitative approaches. We performed a structured literature review focusing on work disability and incorporating aspects of the International Classification of Functioning, Disability, and Health (ICF) as a unifying taxonomy for framework development. Expert interviews provided advice and consultation to enhance face validity of the resulting content models. The content model for work-related behavioral health function identifies five major domains (1) Behavior Control, (2) Basic Interactions, (3) Temperament and Personality, (4) Adaptability, and (5) Workplace Behaviors. The content model describing physical functioning includes three domains (1) Changing and Maintaining Body Position, (2) Whole Body Mobility, and (3) Carrying, Moving and Handling Objects. These content models informed subsequent measurement properties including item development, measurement scale construction, and provided conceptual coherence guiding future empirical inquiry. The proposed measurement approaches show promise to comprehensively and systematically assess physical and behavioral health functioning relevant to work. PMID:23548543

  12. Brain training game boosts executive functions, working memory and processing speed in the young adults: a randomized controlled trial.

    Science.gov (United States)

    Nouchi, Rui; Taki, Yasuyuki; Takeuchi, Hikaru; Hashizume, Hiroshi; Nozawa, Takayuki; Kambara, Toshimune; Sekiguchi, Atsushi; Miyauchi, Carlos Makoto; Kotozaki, Yuka; Nouchi, Haruka; Kawashima, Ryuta

    2013-01-01

    Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults. We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability). Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults. Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields. UMIN Clinical Trial Registry 000005618.

  13. Brain training game boosts executive functions, working memory and processing speed in the young adults: a randomized controlled trial.

    Directory of Open Access Journals (Sweden)

    Rui Nouchi

    Full Text Available BACKGROUND: Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age on a wide range of cognitive functions in young adults. METHODS: We conducted a double-blind (de facto masking randomized controlled trial using a popular brain training game (Brain Age and a popular puzzle game (Tetris. Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris. Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability. RESULTS AND DISCUSSION: Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed in the healthy young adults. CONCLUSIONS: Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields

  14. Effects of payment method on work control, work risk and work-related musculoskeletal health among sewing machine operators

    Directory of Open Access Journals (Sweden)

    R. Nawawi

    2015-12-01

    Full Text Available Effects of payment method on work control, work risk and work-related musculoskeletal health among sewing machine operators R. Nawawi1, B.M. Deros1*, D.D.I. Daruis2, A. Ramli3, R.M. Zein4 and L.H. Joseph3 1Dept. of Mechanical and Materials Engineering Faculty of Engineering & Built Environment Universiti Kebangsaan Malaysia, Malaysia *Email: hjbaba@ukm.edu.my 2Faculty of Engineering, Universiti Pertahanan Nasional Malaysia, Malaysia 3Department of Physiotherapy Faculty of Science, Lincoln University College, Malaysia 4Department of Consultation, Research & Development, National Institute of Occupational Safety and Health (NIOSH, Malaysia ABSTRACT This study aimed to identify payment method and its effects on work control, work risk and work-related musculoskeletal health among Malaysian sewing machine operators. The study sample comprised 337 sewing machine operators (male, n=122, female, n=215; aged between 18-54 years old; mean 30.74±8.44 from four different garment-making companies in Malaysia. They were being paid via time rate wages (n=246 and piece rate wages (n=91. Data was collected through Nordic Musculoskeletal Questionnaire and pen-and-paper assessment via Rapid Upper Limb Assessment (RULA. From the study, the piece rate wage group was found to take fewer breaks, had high work production demands, worked at a faster pace and experienced more exhaustion and pressure due to increasing work demands as compared to the time rate group. They were also observed working with higher physical exposure such as repetitive tasks, awkward static postures, awkward grips and hand movements, pulling, lifting and pushing as compared to those in the time rate wage group. The final RULA scores was also higher from the piece rate wage group (72.53% RULA score 7 which indicated higher work risks among them. The study found that the type of wage payment was significantly associated with work risks (p=0.036, df=1 and WRMSD at the shoulder, lower back

  15. Electron Injection into Organic Semiconductor Devices from High Work Function Cathodes

    National Research Council Canada - National Science Library

    Corey V. Hoven; Renqiang Yang; Andres Garcia; Victoria Crockett; Alan J. Heeger; Guillermo C. Bazan; Thuc-Quyen Nguyen

    2008-01-01

    We show that polymer light-emitting diodes with high work-function cathodes and conjugated polyelectrolyte injection/transport layers exhibit excellent efficiencies despite large electron-injection barriers...

  16. METHODS FOR LOCAL CHANGES IN THE PLASTIC DEFORMATION DIAGNOSTICS ON THE WORK FUNCTION

    Directory of Open Access Journals (Sweden)

    K. V. Panteleyev

    2015-01-01

    Full Text Available The paper describes the electronic work function measurements by the contact potential difference technique, and experimental demonstration of the possibility of these methods application for the stress-strain state of the surface layer of the metals and alloys. The techniques end examples of their application of localization of plastic deformation studies using the Kelvin probe are developed and present. The study topology of work function the deformed surface possible to determine the type of deformation and dynamics of

  17. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection.

    Science.gov (United States)

    Golda-Cepa, M; Syrek, K; Brzychczy-Wloch, M; Sulka, G D; Kotarba, A

    2016-09-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function-bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Molecular Engineering of Azobenzene-Functionalized Polyimides to Enhance Both Photomechanical Work and Motion (POSTPRINT)

    Science.gov (United States)

    2014-09-01

    concentrations of azobenzene in both linear and cross-linked PIs, 30 mol % azobenzene diamine (4) and 20 mol % of azobenzene triamine (7) were added...AFRL-RX-WP-JA-2014-0204 MOLECULAR ENGINEERING OF AZOBENZENE - FUNCTIONALIZED POLYIMIDES TO ENHANCE BOTH PHOTOMECHANICAL WORK AND MOTION...August 2014 4. TITLE AND SUBTITLE MOLECULAR ENGINEERING OF AZOBENZENE - FUNCTIONALIZED POLYIMIDES TO ENHANCE BOTH PHOTOMECHANICAL WORK AND MOTION

  19. Path analysis of empowerment and work effectiveness among staff nurses.

    Science.gov (United States)

    Eo, Yong-Sook; Kim, Young-Hae; Lee, Nae-Young

    2014-03-01

    The purpose of this study was to test a predictive model that could predict and explain work effectiveness among staff nurses at local hospitals. Between April 1 and May 15, 2009, 340 nurses were recruited from two hospitals (one in Ulsan and one in Yangsan). Data were collected via self-administered questionnaires and analyzed using structural equation modeling. A modified model was retained, as the final path model showed a very good fit with the data. Job characteristics and compensation justice were found to have direct and positive effects on empowerment. Job characteristics, transformational leadership, and empowerment were found to directly and positively affect work effectiveness. In addition, job characteristics were found to have a greater effect on empowerment and work effectiveness than other factors do. This structural equation model was used to test the relationships between these factors and work effectiveness. Empowerment mediated the relationship between job characteristics, transformational leadership, and work effectiveness. Findings from this study can be used to design the strategies for increasing work effectiveness in Korean nurses. Copyright © 2014. Published by Elsevier B.V.

  20. Functional MRI investigation of verbal working memory in adults with anorexia nervosa.

    Science.gov (United States)

    Lao-Kaim, N P; Giampietro, V P; Williams, S C R; Simmons, A; Tchanturia, K

    2014-05-01

    Literature regarding verbal working memory (vWM) in anorexia nervosa (AN) has been inconsistent due to a misunderstanding of the key components of vWM and introduction of confounding stimuli. Furthermore, there are no studies looking at how brain function in people with AN relates to vWM performance. The present study used functional magnetic resonance imaging (fMRI) with a letter n-back paradigm to study the effect of increasing vWM task difficulty on cortical functioning in the largest AN sample to date (n=31). Although the AN group had low BMI and higher anxious and depressive symptomology compared to age-matched controls (HC), there were no between-group differences in accuracy and speed at any task difficulty. fMRI data revealed no regions exhibiting significant differences in activation when groups were compared at each difficulty separately and no regions showing group x condition interaction. Although there was a trend towards lower accuracy as duration of illness increased, this was not correlated with activity in regions associated with vWM. These findings indicate that vWM in AN is as efficient and performed using the same cognitive strategy as HC, and that there may not be a need for therapies to pursue remediation of this particular neurocognitive faculty. Crown Copyright © 2013. Published by Elsevier Masson SAS. All rights reserved.

  1. Working memory function is linked to trauma exposure, independently of post-traumatic stress disorder symptoms.

    Science.gov (United States)

    Blanchette, Isabelle; Caparos, Serge

    2016-11-01

    The purpose of the study was to examine how working memory (WM) may be related to exposure to potentially traumatic events and symptoms of post-traumatic stress disorder (PTSD). In four studies, we measured WM function using adaptations of the running span and the reading span tasks. We compared the performance of women reporting experiences of sexual abuse to control participants (total n = 144 controls and 84 victims). We measured severity of the sexual abuse experiences as well as exposure to general life stress. In all studies, trauma-exposed participants showed significantly lower WM function compared to control participants. In addition to traditional null hypothesis testing, we used a mini-meta analysis to estimate the combined estimated effect size of this difference, which was in the moderate range (d = 0.43 with 0.15-0.70 95% confidence interval). Regression equations showed that PTSD symptoms did not mediate the relationship between trauma exposure and WM function. Our results show that trauma exposure per se can be associated with important cognitive correlates even in individuals who do not develop psychopathological reactions.

  2. Time away from work predicts later cognitive function: differences by activity during leave.

    Science.gov (United States)

    Leist, Anja K; Glymour, M Maria; Mackenbach, Johan P; van Lenthe, Frank J; Avendano, Mauricio

    2013-08-01

    We sought to examine how different activities performed during employment gaps are associated with later cognitive function and change. Five cognitive measures were used to indicate cognitive impairment of 18,259 respondents to the Survey of Health, Ageing, and Retirement in Europe (ages 50-73) in 2004/5 or 2006/7. Using complete employment histories, employment gaps of ≥6 months between ages 25 and 65 were identified. Controlling for early life socioeconomic status, school performance, and education, higher risk of cognitive impairment was associated with employment gaps described as unemployment (odds ratio [OR], 1.18; 95% confidence interval [CI], 1.04-1.35) and sickness (OR, 1.78; 95% CI, 1.52-2.09). In contrast, lower risk of cognitive impairment was associated with employment gaps described as training (OR, 0.73; 95% CI, 0.52-1.01) or maternity leave (OR, 0.65; 95% CI, 0.57-0.79). In longitudinal mixed effects models, training and maternity leave were associated with lower 2-year aging-related cognitive decline. Periods away from work described as unemployment or sickness are associated with lower cognitive function, whereas maternity and training leaves are associated with better late-life cognitive function. Both causation and selection mechanisms may explain these findings. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Shift work and its effects on the cardiovascular system

    OpenAIRE

    Mosendane, Thabo; Mosendane, Tshinakaho; Raal, Frederick J.

    2008-01-01

    Summary The practice of shift-work scheduling has long been part of normal work duties in emergency services such as health and security. It is only recently, in the wake of growing job opportunities and booming industries, where more employees are needed to keep services running over 24-hour periods that studies on the effects of shift work on workers’ health have begun to delve deeper. The desynchronisation that occurs in circadian rhythms, with respect to sleep cycles, predisposes employee...

  4. Effects of LMX and differential treatment on work unit commitment.

    Science.gov (United States)

    van Breukelen, Wim; Konst, Dorien; van der Vlist, René

    2002-08-01

    The Leader-Member exchange (LMX) theory of leadership states that leaders do behave differently towards the various members in their work unit. Relatively little attention has been devoted to the question of whether members' perceptions of differential treatment on the part of the leader affects their commitment to the work unit. Perceptions of the amount of differential treatment within their work unit did not explain additional variance in members' work unit commitment after the effects of LMX quality were accounted for. There was, however, a significant interaction effect of LMX quality and differential treatment on work unit commitment. The perception of a large number of differential treatment incidents seems to act as a neutralizer with respect to the positive effects LMX quality may have.

  5. Wage, Work Environment, and Staffing: Effects on Nurse Outcomes

    Science.gov (United States)

    McHugh, Matthew D.; Ma, Chenjuan

    2015-01-01

    Research has shown that hospitals with better nurse staffing and work environments have better nurse outcomes—less burnout, job dissatisfaction, and intention to leave the job. Many studies, however, have not accounted for wage effects, which may confound findings. By using a secondary analysis with cross-sectional administrative data and a four-state survey of nurses, we investigated how wage, work environment, and staffing were associated with nurse outcomes. Logistic regression models, with and without wage, were used to estimate the effects of work environment and staffing on burnout, job dissatisfaction, and intent to leave. We discovered that wage was associated with job dissatisfaction and intent to leave but had little influence on burnout, while work environment and average patient-to-nurse ratio still have considerable effects on nurse outcomes. Wage is important for good nurse outcomes, but it does not diminish the significant influence of work environment and staffing on nurse outcomes. PMID:25121923

  6. Variations in erosive wear of metallic materials with temperature via the electron work function

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaochen; Yu, Bin [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 (Canada); Yan, X.G. [School of Mechanical Engineering, Taiyuan University of Science and Technology, Taiyuan, Shanxi (China); Li, D.Y., E-mail: dongyang.li@ualberta.ca [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 (Canada); School of Mechanical Engineering, Taiyuan University of Science and Technology, Taiyuan, Shanxi (China)

    2016-04-01

    Mechanical properties of metals are intrinsically determined by their electron behavior, which is largely reflected by the electron work function (EWF or φ). Since the work function varies with temperature, the dependence of material properties on temperature could be predicted via variations in work function with temperature. Combining a hardness – φ relationship and the dependence of work function on temperature, a temperature-dependent model for predicting solid-particle erosion is proposed. Erosive wear losses of copper, nickel, and carbon steel as sample materials were measured at different temperatures. Results of the tests are consistent with the theoretical prediction. This study demonstrates a promising parameter, electron work function, for looking into fundamental aspects of wear phenomena, which would also help develop alternative methodologies for material design. - Highlights: • Metallic materials' wear resistance is influenced by temperature. • Electron work function (EWF) intrinsically determines materials' wear resistance. • An EWF-based temperature-dependent solid-particle erosion model is proposed.

  7. The cross-cultural adaptation of the Work Role Functioning Questionnaire to Dutch

    NARCIS (Netherlands)

    Abma, Femke I.; Amick, Benjamin C.; Brouwer, Sandra; van der Klink, Jac J. L.; Bultmann, Ute

    2012-01-01

    Objective: The study objectives were to performa cross-cultural adaptation of the Work Role Functioning Questionnaire, a health-related work outcome measure, into Dutch and to assess the questionnaire's reliability and validity in the Dutch context (WRFQ-DV). Participants: 40 workers with a health

  8. Neural correlates of enhanced working-memory performance in dissociative disorder: a functional MRI study

    NARCIS (Netherlands)

    Elzinga, Bernet M.; Ardon, Angelique M.; Heijnis, Maaike K.; de Ruiter, Michiel B.; van Dyck, Richard; Veltman, Dick J.

    2007-01-01

    BACKGROUND: Memory functioning has been highlighted as a central issue in pathological dissociation. In non-pathological dissociation, evidence for enhanced working memory has been found, together with greater task-load related activity. So far, no imaging studies have investigated working memory in

  9. Test-retest reliability of the isernhagen work systems functional capacity evaluation in healthy adults

    NARCIS (Netherlands)

    Reneman, MF; Brouwer, S; Meinema, A; Dijkstra, PU; Geertzen, JHB; Groothoff, JW

    2004-01-01

    Aim of this study was to investigate test-retest reliability of the Isernhagen Work System Functional Capacity Evaluation (IWS FCE) in healthy subjects. The IWS FCE consists of 28 tests that reflect work-related activities such as lifting, carrying, bending, etc. A convenience sample of 26 healthy

  10. The repetition effect in building and construction works

    DEFF Research Database (Denmark)

    Gottlieb, Stefan Christoffer; Haugbølle, Kim

    This report summarises the results from the work undertaken for the Public Transport Authority on the effect of learning and repetition in building and construction works. The results are applied by the Public Transport Authority in a new budgeting model, while the agency investigates...

  11. Effect of sporting activity on absenteeism in a working population

    NARCIS (Netherlands)

    Heuvel, S.G. van den; Boshuizen, H.C.; Hildebrandt, V.H.; Blatter, B.M.; Ariëns, G.A.; Bongers, P.M.

    2005-01-01

    OBJECTIVES: To determine the effects of sporting activity on absenteeism in a working population. METHODS: Data were used from a prospective cohort study in a working population with a follow up period of 3 years and were collected with yearly questionnaires or collected from company records.

  12. Differential age effects on spatial and visual working memory

    NARCIS (Netherlands)

    Oosterman, J.M.; Morel, S.; Meijer, L.; Buvens, C.; Kessels, R.P.C.; Postma, A.

    2011-01-01

    The present study was intended to compare age effects on visual and spatial working memory by using two versions of the same task that differed only in presentation mode. The working memory task contained both a simultaneous and a sequential presentation mode condition, reflecting, respectively,

  13. Investigating the Effectiveness of Group Work in Mathematics

    Science.gov (United States)

    Sofroniou, Anastasia; Poutos, Konstantinos

    2016-01-01

    Group work permits students to develop a range of critical thinking, analytical and communication skills; effective team work; appreciation and respect for other views, techniques and problem-solving methods, all of which promote active learning and enhance student learning. This paper presents an evaluation of employing the didactic and…

  14. The Effects of Integrating Laboratory Work with Theory on Academic ...

    African Journals Online (AJOL)

    The major findings of the study showed that students taught physics by intergrating laboratory work with theory performed better than those taught by treating practical work after and separate from theory. Gender showed no significant effects. It was therefore recommended that physics teachers should adopt the method of ...

  15. A compact model for single material double work function gate MOSFET

    Science.gov (United States)

    Changyong, Zheng; Wei, Zhang; Tailong, Xu; Yuehua, Dai; Junning, Chen

    2013-09-01

    An analytical surface potential model for the single material double work function gate (SMDWG) MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes the effects of drain biases, gate oxide thickness, different combinations of S-gate and D-gate length and values of substrate doping concentration. More attention has been paid to seeking to explain the attributes of the SMDWG MOSFET, such as suppressing drain-induced barrier lowering (DIBL), accelerating carrier drift velocity and device speed. The model is verified by comparison to the simulated results using the device simulator MEDICI. The accuracy of the results obtained using our analytical model is verified using numerical simulations. The model not only offers the physical insight into device physics but also provides the basic designing guideline for the device.

  16. Evaluation of physiological functions and human operator working in extreme conditions

    Directory of Open Access Journals (Sweden)

    П.В. Білошицький

    2009-03-01

    Full Text Available  Some methods and results of psycho-physiological human functions investigation in mountain conditions are given. These results form the base of developed approaches for professional selection of special contingents for the work in extreme conditions. Mathematic model for reliability of human nervous system functioning in extreme conditions is suggested.

  17. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection

    Energy Technology Data Exchange (ETDEWEB)

    Golda-Cepa, M., E-mail: golda@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Syrek, K. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Brzychczy-Wloch, M. [Department of Bacteriology, Microbial Ecology and Parasitology, Jagiellonian University Medical College, Czysta 18, 31-121 Krakow (Poland); Sulka, G.D. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Kotarba, A., E-mail: kotarba@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland)

    2016-09-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function–bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces. - Highlights: • The correlation between work function and bacteria adhesion was discovered. • The discovered correlation is rationalized in terms of electrostatic bacteria–surface repulsion. • The results provide basis for the simple evaluation of implant surfaces against infection.

  18. The Work Role Functioning Questionnaire 2.0 (Dutch Version) : Examination of its Reliability, Validity and Responsiveness in the General Working Population

    NARCIS (Netherlands)

    Abma, Femke I.; van der Klink, Jac J. L.; Bultmann, Ute

    Purpose: The promotion of a sustainable, healthy and productive working life attracts more and more attention. Recently the Work Role Functioning Questionnaire (WRFQ) has been cross-culturally translated and adapted to Dutch. This questionnaire aims to measure the health-related work functioning of

  19. Strategic games and truly playable effectivity functions

    DEFF Research Database (Denmark)

    Goranko, Valentin; Jamroga, Wojciech; Turrini, Paolo

    2013-01-01

    A well-known result in the logical analysis of cooperative games states that the so-called playable effectivity functions exactly correspond to strategic games. More precisely, this result states that for every playable effectivity function E there exists a strategic game that assigns to coalitions...... of players exactly the same power as E, and every strategic game generates a playable effectivity function. While the latter direction of the correspondence is correct, we show that the former does not hold for a number of infinite state games. We point out where the original proof of correspondence goes...... wrong, and we present examples of playable effectivity functions for which no equivalent strategic game exists. Then, we characterize the class of truly playable effectivity functions, that do correspond to strategic games. Moreover, we discuss a construction that transforms any playable effectivity...

  20. Is functional integration of resting state brain networks an unspecific biomarker for working memory performance?

    Science.gov (United States)

    Alavash, Mohsen; Doebler, Philipp; Holling, Heinz; Thiel, Christiane M; Gießing, Carsten

    2015-03-01

    Is there one optimal topology of functional brain networks at rest from which our cognitive performance would profit? Previous studies suggest that functional integration of resting state brain networks is an important biomarker for cognitive performance. However, it is still unknown whether higher network integration is an unspecific predictor for good cognitive performance or, alternatively, whether specific network organization during rest predicts only specific cognitive abilities. Here, we investigated the relationship between network integration at rest and cognitive performance using two tasks that measured different aspects of working memory; one task assessed visual-spatial and the other numerical working memory. Network clustering, modularity and efficiency were computed to capture network integration on different levels of network organization, and to statistically compare their correlations with the performance in each working memory test. The results revealed that each working memory aspect profits from a different resting state topology, and the tests showed significantly different correlations with each of the measures of network integration. While higher global network integration and modularity predicted significantly better performance in visual-spatial working memory, both measures showed no significant correlation with numerical working memory performance. In contrast, numerical working memory was superior in subjects with highly clustered brain networks, predominantly in the intraparietal sulcus, a core brain region of the working memory network. Our findings suggest that a specific balance between local and global functional integration of resting state brain networks facilitates special aspects of cognitive performance. In the context of working memory, while visual-spatial performance is facilitated by globally integrated functional resting state brain networks, numerical working memory profits from increased capacities for local processing

  1. Work-Related Health Effects among Wastewater Treatment Plants Workers

    Directory of Open Access Journals (Sweden)

    MA Albatanony

    2011-09-01

    Full Text Available Background: Raw sewage contains various pathogenic organisms including bacteria, viruses, fungus, worms and protozoa. Workers at wastewater treatment plants (WWTPs are exposed to these organisms as well as to H2S gas causing many health hazards. Objectives: To assess some work-related health effects among WWTPs workers with special emphasis on the most common infections as well as cardiopulmonary disorders. Methods: 43 workers at Berket Al-Sabih WWTPs were studied. An equal number of non-exposed comparison group were also studied. All participants were asked about their personal demographic data, symptoms suggesting infection, respiratory tract impairment and cardiovascular manifestations. Spirometric measurements were made at the end of the work shift. A resting standard 12-lead ECG was also taken for each participant. For those with a positive ECG finding, echocardiography was also performed. Serum examination for antibodies against hepatitis A virus (HAV and hepatitis E virus (HEV was also done. A heparinized blood sample to measure sulf-hemoglobin, as an indicator of H2S exposure, was taken. Stool was analyzed by polymerase chain reaction (PCR for Leptospira spirochete. Results: WWTPs workers suffered from body ache, abdominal pain, wheeze, asthma and dyspnea more frequently than the comparison group (p<0.05. An obstructive pattern of pulmonary function impairment and a higher mean sulf-hemoglobin% were significantly more common among WWTPs workers than the comparison group. Antibody levels against HAV and HEV as well as frequency of positive stool PCR test results for L. spirochete were significantly higher among WWTPs workers than the comparison group. The prevalence of left ventricular hypertrophy (LVH according to ECG and mean ejection fraction (EF as measured by echocardiography were significantly more frequent in WWTPs workers than in the comparison group. Conclusion: WWTPs workers are high risk of developing various infections and

  2. Functional connectivity among multi-channel EEGs when working memory load reaches the capacity.

    Science.gov (United States)

    Zhang, Dan; Zhao, Huipo; Bai, Wenwen; Tian, Xin

    2016-01-15

    Evidence from behavioral studies has suggested a capacity existed in working memory. As the concept of functional connectivity has been introduced into neuroscience research in the recent years, the aim of this study is to investigate the functional connectivity in the brain when working memory load reaches the capacity. 32-channel electroencephalographs (EEGs) were recorded for 16 healthy subjects, while they performed a visual working memory task with load 1-6. Individual working memory capacity was calculated according to behavioral results. Short-time Fourier transform was used to determine the principal frequency band (theta band) related to working memory. The functional connectivity among EEGs was measured by the directed transform function (DTF) via spectral Granger causal analysis. The capacity was 4 calculated from the behavioral results. The power was focused in the frontal midline region. The strongest connectivity strengths of EEG theta components from load 1 to 6 distributed in the frontal midline region. The curve of DTF values vs load numbers showed that DTF increased from load 1 to 4, peaked at load 4, then decreased after load 4. This study finds that the functional connectivity between EEGs, described quantitatively by DTF, became less strong when working memory load exceeded the capacity. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Effects of reservoir squeezing on quantum systems and work extraction

    Science.gov (United States)

    Huang, X. L.; Wang, Tao; Yi, X. X.

    2012-11-01

    We establish a quantum Otto engine cycle in which the working substance contacts with squeezed reservoirs during the two quantum isochoric processes. We consider two working substances: (1) a qubit and (2) two coupled qubits. Due to the effects of squeezing, the working substance can be heated to a higher effective temperature, which leads to many interesting features different from the ordinary ones, such as (1) for the qubit as working substance, if we choose the squeezed parameters properly, the positive work can be exported even when TH

  4. Age old antipodes united: stable and low-work-function surfaces are generic

    Science.gov (United States)

    Uijttewaal, M. A.; de Wijs, G. A.; de Groot, R. A.

    2006-03-01

    Both a low work function and a stable surface are crucial for the application of cathodes in e.g. microwave ovens, organic photoconductors and displays as CRTs and OLEDs. Until recently they were considered antipodes. In previous work[1] we showed a stable low-work-function surface to be realised for the compound BaAl4 and even predicted that stable, low-work-function surfaces would be generic for metals with polar surfaces. Now, ab initio calculations confirm the prediction for the compounds CaAl4, BaAuIn3 and LaB6.[1] M.A. Uijttewaal, G.A. de Wijs, R.A. de Groot, R. Coehoorn, V. van Elsbergen, and C. H. L. Weijtens, Chem. Mater. 17, 3879 (2005)

  5. Selective Attention, Working Memory, and Executive Function as Potential Independent Sources of Cognitive Dysfunction in Schizophrenia.

    Science.gov (United States)

    Gold, James M; Robinson, Benjamin; Leonard, Carly J; Hahn, Britta; Chen, Shuo; McMahon, Robert P; Luck, Steven J

    2017-11-11

    People with schizophrenia demonstrate impairments in selective attention, working memory, and executive function. Given the overlap in these constructs, it is unclear if these represent distinct impairments or different manifestations of one higher-order impairment. To examine this question, we administered tasks from the basic cognitive neuroscience literature to measure visual selective attention, working memory capacity, and executive function in 126 people with schizophrenia and 122 healthy volunteers. Patients demonstrated deficits on all tasks with the exception of selective attention guided by strong bottom-up inputs. Although the measures of top-down control of selective attention, working memory, and executive function were all intercorrelated, several sources of evidence indicate that working memory and executive function are separate sources of variance. Specifically, both working memory and executive function independently contributed to the discrimination of group status and independently accounted for variance in overall general cognitive ability as assessed by the MATRICS battery. These two cognitive functions appear to be separable features of the cognitive impairments observed in schizophrenia. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. The effect of informal care on work and wages.

    Science.gov (United States)

    Van Houtven, Courtney Harold; Coe, Norma B; Skira, Meghan M

    2013-01-01

    Cross-sectional evidence in the United States finds that informal caregivers have less attachment to the labor force. The causal mechanism is unclear: do children who work less become informal caregivers, or are children who become caregivers working less? Using longitudinal data from the Health and Retirement Study, we identify the relationship between informal care and work in the United States, both on the intensive and extensive margins, and examine wage effects. We control for time-invariant individual heterogeneity; rule out or control for endogeneity; examine effects for men and women separately; and analyze heterogeneous effects by task and intensity. We find modest decreases-2.4 percentage points-in the likelihood of working for male caregivers providing personal care. Female chore caregivers, meanwhile, are more likely to be retired. For female care providers who remain working, we find evidence that they decrease work by 3-10hours per week and face a 3 percent lower wage than non-caregivers. We find little effect of caregiving on working men's hours or wages. These estimates suggest that the opportunity costs to informal care providers are important to consider when making policy recommendations about the design and funding of public long-term care programs. Published by Elsevier B.V.

  7. Differential Effects of Alcohol Consumption Behaviours on Working Memory Processes

    Directory of Open Access Journals (Sweden)

    Shaunak Sanjay Deshpande

    2015-11-01

    Full Text Available Alcohol exposure in a clinical population impairs working memory. In order to establish the effects of alcohol on working memory in typical young adults, this study looked at their alcohol consumption behaviours and how they predict working memory. A battery of cognitive tasks and a recreational drug use questionnaire assessed working memory and alcohol consumption of 100 participants. The results revealed that alcohol abstinence predicted set-shifting, verbal executive, phonological loop, spatial and visual working memory performance, which is consistent with current literature. I surmise that the recent use of alcohol plays a role in working memory impairments and offer novel findings that the length of abstinence plays a role in the cognitive recovery of young adults.

  8. Work function reduction by a redox-active organometallic sandwich complex

    KAUST Repository

    Hyla, Alexander

    2016-07-14

    We have investigated, at the density functional theory level, the geometric and electronic structures of the pentamethyliridocene (IrCpCp*) monomer and dimer adsorbed on the Au(111) and indium tin oxide (ITO) (222) surfaces, as well as their impact on the work functions. Our calculations show that the adsorption of a monomer lowers the work function of ITO(222) by 1.2 eV and Au(111) by 1.2–1.3 eV. The main origin for this reduction is the formation of an interface dipole between the monomer and the substrate via charge transfer. Dimer adsorption as well as adsorption of possible byproducts formed from dimer bond-cleavage in solution, show a lesser ability to lower the work function. © 2016 Elsevier B.V.

  9. The work function for Li+-ion emission from spodumene: A complete characterization of thermionic emission

    Science.gov (United States)

    Schuld, Stephan; Diekmann, Mira; Schäfer, Martin; Weitzel, Karl-Michael

    2016-11-01

    The thermionic emission of Li+ from synthetic spodumene (LiAlSi2O6) has been investigated as a function of temperature and electric field. The data presented cover the entire range from the space charge limited Child-Langmuir regime, to the Richardson-Dushman regime, and finally the field assisted Schottky regime. From a self-consistent analysis of all data measured, the work function for Li+ emission from synthetic spodumene is determined as (2.47 ± 0.015) eV. The thermionic currents exhibit a voltage offset of (1.7 ± 0.1) eV, which can be traced to a combination of the ionic work function of the emitter, the recombination energy Li+ + electron, the electronic work function of the detector, and the contact potential between the detector and filament.

  10. Meaningful work for a meaningful life? Work alienation and its effects in the work and the family context

    NARCIS (Netherlands)

    L.G. Tummers (Lars); L. den Dulk (Laura)

    2011-01-01

    textabstractAbstract: This paper examines the impact of work alienation on work-related outcomes (organizational commitment and work effort), and its impact outside work (work-family enrichment). Hypotheses are formulated based on two research streams: sociology of work and organization in relation

  11. EFFECT OF SCHOOL CLIMATE, WORK STRESS AND WORK MOTIVATION ON THE PERFORMANCE OF TEACHER

    Directory of Open Access Journals (Sweden)

    Ramlani Lina Sinaulan

    2016-12-01

    Full Text Available Performance is a form of behavior of a person or organization with achievement orientation. The study results are known (a the school climate affect performance of teachers, b there is influence of work stress on teacher performance, (c work motivation effect on teacher performance, d school climate influence on job motivation of teachers, and (e work stress effect on work motivation of teachers. Suggestions studies (a improving teacher performance should the top priority schools in school management efforts. This condition given that performance of teachers are the main pillars that determine the success of the school in improving quality of students. Therefore, performance of the teacher must always be good and necessary to update the knowledge of teachers on the latest information in education as benchmarks increase teacher performance, (b job motivation of teachers needs to improved, among others, with reward and punishment impartial towards the success achieved by the teacher as well as the violations committed so that it becomes part of an effort to motivate teachers to work.

  12. The effects of emotional intelligence on counterproductive work behaviors

    Directory of Open Access Journals (Sweden)

    Seyed Morteza Emami

    2014-08-01

    Full Text Available This paper presents an empirical investigation to study the effects of emotional intelligence on counterproductive work behavior. The study uses a questionnaire for measuring the effects of emotional intelligence, which consists of four components including self-awareness, self-control, self-motivation and empathy. In addition, the study uses another questionnaire to measure the effects of counterproductive work behavior. The study has accomplished among full time employees who work for Industrial Projects Management of Iran (IPMI, as a general contractor, undertakes EPC projects in field of oil, gas and petrochemical industries in Iran. Using structural equation modeling, the study has determined a negative and meaningful relationship between various components of emotional intelligence and counterproductive work behavior.

  13. Functional genetic variation of the cannabinoid receptor 1 and cannabis use interact on prefrontal connectivity and related working memory behavior.

    Science.gov (United States)

    Colizzi, Marco; Fazio, Leonardo; Ferranti, Laura; Porcelli, Annamaria; Masellis, Rita; Marvulli, Daniela; Bonvino, Aurora; Ursini, Gianluca; Blasi, Giuseppe; Bertolino, Alessandro

    2015-02-01

    Cannabinoid signaling is involved in different brain functions and it is mediated by the cannabinoid receptor 1 (CNR1), which is encoded by the CNR1 gene. Previous evidence suggests an association between cognition and cannabis use. The logical interaction between genetically determined cannabinoid signaling and cannabis use has not been determined. Therefore, we investigated whether CNR1 variation predicts CNR1 prefrontal mRNA expression in postmortem prefrontal human tissue. Then, we studied whether functional variation in CNR1 and cannabis exposure interact in modulating prefrontal function and related behavior during working memory processing. Thus, 208 healthy subjects (113 males) were genotyped for the relevant functional SNP and were evaluated for cannabis use by the Cannabis Experience Questionnaire. All individuals performed the 2-back working memory task during functional magnetic resonance imaging. CNR1 rs1406977 was associated with prefrontal mRNA and individuals carrying a G allele had reduced CNR1 prefrontal mRNA levels compared with AA subjects. Moreover, functional connectivity MRI demonstrated that G carriers who were also cannabis users had greater functional connectivity in the left ventrolateral prefrontal cortex and reduced working memory behavioral accuracy during the 2-back task compared with the other groups. Overall, our results indicate that the deleterious effects of cannabis use are more evident on a specific genetic background related to its receptor expression.

  14. Sleep and cognitive function of crewmembers and mission controllers working 24-h shifts during a simulated 105-day spaceflight mission

    Science.gov (United States)

    Barger, Laura K.; Wright, Kenneth P.; Burke, Tina M.; Chinoy, Evan D.; Ronda, Joseph M.; Lockley, Steven W.; Czeisler, Charles A.

    2014-01-01

    The success of long-duration space missions depends on the ability of crewmembers and mission support specialists to be alert and maintain high levels of cognitive function while operating complex, technical equipment. We examined sleep, nocturnal melatonin levels and cognitive function of crewmembers and the sleep and cognitive function of mission controllers who participated in a high-fidelity 105-day simulated spaceflight mission at the Institute of Biomedical Problems (Moscow). Crewmembers were required to perform daily mission duties and work one 24-h extended duration work shift every sixth day. Mission controllers nominally worked 24-h extended duration shifts. Supplemental lighting was provided to crewmembers and mission controllers. Participants' sleep was estimated by wrist-actigraphy recordings. Overall, results show that crewmembers and mission controllers obtained inadequate sleep and exhibited impaired cognitive function, despite countermeasure use, while working extended duration shifts. Crewmembers averaged 7.04±0.92 h (mean±SD) and 6.94±1.08 h (mean±SD) in the two workdays prior to the extended duration shifts, 1.88±0.40 h (mean±SD) during the 24-h work shift, and then slept 10.18±0.96 h (mean±SD) the day after the night shift. Although supplemental light was provided, crewmembers' average nocturnal melatonin levels remained elevated during extended 24-h work shifts. Naps and caffeine use were reported by crewmembers during ˜86% and 45% of extended night work shifts, respectively. Even with reported use of wake-promoting countermeasures, significant impairments in cognitive function were observed. Mission controllers slept 5.63±0.95 h (mean±SD) the night prior to their extended duration work shift. On an average, 89% of night shifts included naps with mission controllers sleeping an average of 3.4±1.0 h (mean±SD) during the 24-h extended duration work shift. Mission controllers also showed impaired cognitive function during extended

  15. Conceptual foundation for measures of physical function and behavioral health function for Social Security work disability evaluation.

    Science.gov (United States)

    Marfeo, Elizabeth E; Haley, Stephen M; Jette, Alan M; Eisen, Susan V; Ni, Pengsheng; Bogusz, Kara; Meterko, Mark; McDonough, Christine M; Chan, Leighton; Brandt, Diane E; Rasch, Elizabeth K

    2013-09-01

    Physical and mental impairments represent the 2 largest health condition categories for which workers receive Social Security disability benefits. Comprehensive assessment of physical and mental impairments should include aspects beyond medical conditions such as a person's underlying capabilities as well as activity demands relevant to the context of work. The objective of this article is to describe the initial conceptual stages of developing new measurement instruments of behavioral health and physical functioning relevant for Social Security work disability evaluation purposes. To outline a clear conceptualization of the constructs to be measured, 2 content models were developed using structured and informal qualitative approaches. We performed a structured literature review focusing on work disability and incorporating aspects of the International Classification of Functioning, Disability and Health as a unifying taxonomy for framework development. Expert interviews provided advice and consultation to enhance face validity of the resulting content models. The content model for work-related behavioral health function identifies 5 major domains: (1) behavior control, (2) basic interactions, (3) temperament and personality, (4) adaptability, and (5) workplace behaviors. The content model describing physical functioning includes 3 domains: (1) changing and maintaining body position, (2) whole-body mobility, and (3) carrying, moving, and handling objects. These content models informed subsequent measurement properties including item development and measurement scale construction, and provided conceptual coherence guiding future empirical inquiry. The proposed measurement approaches show promise to comprehensively and systematically assess physical and behavioral health functioning relevant to work. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  16. Investigating the Effectiveness of Group Work in Mathematics

    Directory of Open Access Journals (Sweden)

    Anastasia Sofroniou

    2016-09-01

    Full Text Available Group work permits students to develop a range of critical thinking, analytical and communication skills; effective team work; appreciation and respect for other views, techniques and problem-solving methods, all of which promote active learning and enhance student learning. This paper presents an evaluation of employing the didactic and pedagogical customs of group work in mathematics with the aim of improving student performance as well as exploring students’ perceptions of working in groups. The evaluation of group work was carried out during tutorial time with first year civil engineering students undertaking a mathematics module in their second semester. The aim was to investigate whether group work learning can help students gain a deeper understanding of the module content, develop improved critical and analytical thinking skills and see if this method of pedagogy can produce higher performance levels. The group work sessions were conducted over four weeks whilst studying the topic of integration. Evaluation surveys were collected at the end of the intervention along with an investigation into the examination results from the end of semester examinations. In order to derive plausible and reasonable conclusions, these examination results were compared with an analogous cohort of first year mathematics students, also studying integration in their engineering-based degree. The investigation into the effectiveness of group work showed interesting and encouraging positive outcomes, supported by a combination of qualitative and quantitative analysis.

  17. Influence of H2 and D2 plasmas on the work function of caesiated materials

    Science.gov (United States)

    Friedl, R.; Fantz, U.

    2017-08-01

    Caesium-covered surfaces are used in negative hydrogen ion sources as a low work function converter for H-/D- surface production. The work function χ of the converter surface is one of the key parameters determining the performance of the ion source. Under idealized conditions, pure bulk Cs has 2.14 eV. However, residual gases at ion source background pressures of 10-7-10-6 mbar and the plasma surface interaction with the hydrogen discharge in front of the caesiated surface dynamically affect the actual surface work function. Necessary fundamental investigations on the resulting χ are performed at a dedicated laboratory experiment. Under the vacuum conditions of ion sources, the incorporation of impurities into the Cs layer leads to very stable Cs compounds. The result is a minimal work function of χvac ≈ 2.75 eV for Cs evaporation rates of up to 10 mg/h independent of substrate material and surface temperature (up to 260 °C). Moreover, a distinct degradation behavior can be observed in the absence of a Cs flux onto the surface leading to a deterioration of the work function by about 0.1 eV/h. However, in a hydrogen discharge with plasma parameters close to those of ion sources, fluxes of reactive hydrogen species and VUV photons impact on the surface which reduces the work function of the caesiated substrate down to about 2.6 eV even without Cs supply. Establishing a Cs flux onto the surface with ΓCs ≈ 1017 m-2 s-1 further enhances the work function obtaining values around 2.1 eV, which can be maintained stable for several hours of plasma exposure. Hence, Cs layers with work functions close to that of pure bulk Cs can be achieved for both H2 and D2 plasmas. Isotopic differences can be neglected within the measurement accuracy of about 0.1 eV due to comparable plasma parameters. Furthermore, after shutting down the Cs evaporation, continuing plasma exposure helps against degradation of the Cs layer resulting in a constant low work function for at least 1 h.

  18. Is Working Memory Training Effective? A Meta-Analytic Review

    Science.gov (United States)

    Melby-Lervag, Monica; Hulme, Charles

    2013-01-01

    It has been suggested that working memory training programs are effective both as treatments for attention-deficit/hyperactivity disorder (ADHD) and other cognitive disorders in children and as a tool to improve cognitive ability and scholastic attainment in typically developing children and adults. However, effects across studies appear to be…

  19. Drawing a dog: The role of working memory and executive function.

    Science.gov (United States)

    Panesi, Sabrina; Morra, Sergio

    2016-12-01

    Previous research suggests that young children draw animals by adapting their scheme for the human figure. This can be considered an early form of drawing flexibility. This study investigated preschoolers' ability to draw a dog that is different from the human figure. The role of working memory capacity and executive function was examined. The participants were 123 children (36-73 months old) who were required to draw both a person and a dog. The dog figure was scored on a list of features that could render it different from the human figure. Regression analyses showed that both working memory capacity and executive function predicted development in the dog drawing; the dog drawing score correlated with working memory capacity and executive function, even partialling out age, motor coordination, and drawing ability (measured with Goodenough's Draw-a-Man test). These results suggest that both working memory capacity and executive function play an important role in the early development of drawing flexibility. The implications regarding executive functions and working memory are also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Working solutions -- Honduras. ASHONPLAFA analyzes the management functions of central and regional managers.

    Science.gov (United States)

    1995-01-01

    ASHONPLAFA is the principal provider of family planning services in Honduras. The organization has 260 employees, runs six medical centers and 1900 community distribution service sites in six regions of the country, and administers a social marketing program from its head office in Tegucigalpa. ASHONPLAFA has grown significantly in the last few years. To respond to the increased growth and make sure that ASHONPLAFA's programs were able to respond quickly and effectively to clients' needs, senior managers at the organization began considering ways in which the organization could increase efficiency, expand service coverage, and recover more program costs. ASHONPLAFA needed to analyze the systems they used to manage their programs as well as the various management styles of their staff and the institutional culture in which they had become accustomed to working. Throughout the process, ASHONPLAFA has consistently examined the extent to which program functions were being successfully managed by the central and regional managers, assessed the impact of the changes on program performance, and determined what additional training might be necessary for managers given their new roles. General issues are presented followed by consideration of the analysis of management functions in the following areas: strategic and operational planning, information systems, mass media communication, income generation and fund raising, marketing, new services, and service fees and clinic hours. The following initiatives were determined to be those which would directly support the achievement of ASHONPLAFA's objectives for 1995: the transfer of new responsibilities, technical assistance, new initiatives, and evaluation.

  1. The design of a new spiking neuron using dual work function silicon nanowire transistors

    Energy Technology Data Exchange (ETDEWEB)

    Bindal, Ahmet [Computer Engineering Department, San Jose State University, One Washington Square, San Jose, CA 95192 (United States); Hamedi-Hagh, Sotoudeh [Electrical Engineering Department, San Jose State University, One Washington Square, San Jose, CA 95192 (United States)

    2007-03-07

    A new spike neuron cell is designed using vertically grown, undoped silicon nanowire transistors. This study presents an entire design cycle from designing and optimizing vertical nanowire transistors for minimal power dissipation to realizing a neuron cell and measuring its dynamic power consumption, performance and layout area. The design cycle starts with determining individual metal gate work functions for NMOS and PMOS transistors as a function of wire radius to produce a 300 mV threshold voltage. The wire radius and effective channel length are subsequently varied to find a common body geometry for both transistors that yields smaller than 1 pA OFF current while producing maximum drive currents. A spike neuron cell is subsequently built using these transistors to measure its transient performance, power dissipation and layout area. Post-layout simulation results indicate that the neuron consumes 0.397 {mu}W to generate a +1 V and 1.12 {mu}W to generate a -1 V output pulse for a fan-out of five synapses at 500 MHz; the power dissipation increases by approximately 3 nW for each additional synapse at the output for generating either pulse. The neuron circuit occupies approximately 0.27 {mu}m{sup 2}.

  2. The impact of NMDA receptor blockade on human working memory-related prefrontal function and connectivity.

    Science.gov (United States)

    Driesen, Naomi R; McCarthy, Gregory; Bhagwagar, Zubin; Bloch, Michael H; Calhoun, Vincent D; D'Souza, Deepak C; Gueorguieva, Ralitza; He, George; Leung, Hoi-Chung; Ramani, Ramachandran; Anticevic, Alan; Suckow, Raymond F; Morgan, Peter T; Krystal, John H

    2013-12-01

    Preclinical research suggests that N-methyl-D-aspartate glutamate receptors (NMDA-Rs) have a crucial role in working memory (WM). In this study, we investigated the role of NMDA-Rs in the brain activation and connectivity that subserve WM. Because of its importance in WM, the lateral prefrontal cortex, particularly the dorsolateral prefrontal cortex and its connections, were the focus of analyses. Healthy participants (n=22) participated in a single functional magnetic resonance imaging session. They received saline and then the NMDA-R antagonist ketamine while performing a spatial WM task. Time-course analysis was used to compare lateral prefrontal activation during saline and ketamine administration. Seed-based functional connectivity analysis was used to compare dorsolateral prefrontal connectivity during the two conditions and global-based connectivity was used to test for laterality in these effects. Ketamine reduced accuracy on the spatial WM task and brain activation during the encoding and early maintenance (EEM) period of task trials. Decrements in task-related activation during EEM were related to performance deficits. Ketamine reduced connectivity in the DPFC network bilaterally, and region-specific reductions in connectivity were related to performance. These results support the hypothesis that NMDA-Rs are critical for WM. The knowledge gained may be helpful in understanding disorders that might involve glutamatergic deficits such as schizophrenia and developing better treatments.

  3. Sleep disturbances and reduced work functioning in depressive or anxiety disorders.

    Science.gov (United States)

    van Mill, Josine G; Vogelzangs, Nicole; Hoogendijk, Witte J G; Penninx, Brenda W J H

    2013-11-01

    We aimed to examine the associations between sleep disturbances and work functioning in an epidemiologic cohort study in subjects with or without depressive or anxiety disorders. There were 707 subjects included in our analyses with depressive or anxiety disorders and 728 subjects without current depressive or anxiety disorders. Insomnia was defined as a score ≥9 using the Insomnia Rating Scale. Self-reported sleep duration was categorized in short, normal, and long (≤6, 7-9, and ≥10 h, respectively). Work absenteeism was defined as none, short (≤2 weeks), or long (>2 weeks). Work performance was defined as not impaired, reduced, or impaired. Logistic regression analyses were performed to examine the associations of sleep disturbances with work functioning. In subjects with psychopathology, insomnia and short sleep duration were significantly associated with impaired work performance (odds ratio [OR] for insomnia, 2.20; [95% confidence interval {CI}, 1.50-3.22]; OR for short sleep, 2.54 [95% CI, 1.66-3.88] compared to normal sleep duration). Insomnia (OR, 2.48 [95% CI, 1.67-3.69]) and short sleep duration (OR, 1.85 [95% CI, 1.23-2.78]) also were associated with long-term absenteeism. These findings remained the same after considering clinical characteristics including medication use and symptom severity. In subjects without psychopathology, no significant associations were found between insomnia and short sleep duration on work functioning after considering subthreshold depression symptoms. In subjects with psychopathology, sleep disturbances were negatively associated with work functioning, independent of disorder severity and use of psychotropic medication. Further research is needed to determine if treatment of sleep disturbances in subjects with psychopathology improves work functioning. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Work function and surface stability of tungsten-based thermionic electron emission cathodes

    Science.gov (United States)

    Jacobs, Ryan; Morgan, Dane; Booske, John

    2017-11-01

    Materials that exhibit a low work function and therefore easily emit electrons into vacuum form the basis of electronic devices used in applications ranging from satellite communications to thermionic energy conversion. W-Ba-O is the canonical materials system that functions as the thermionic electron emitter commercially used in a range of high-power electron devices. However, the work functions, surface stability, and kinetic characteristics of a polycrystalline W emitter surface are still not well understood or characterized. In this study, we examined the work function and surface stability of the eight lowest index surfaces of the W-Ba-O system using density functional theory methods. We found that under the typical thermionic cathode operating conditions of high temperature and low oxygen partial pressure, the most stable surface adsorbates are Ba-O species with compositions in the range of Ba0.125O-Ba0.25O per surface W atom, with O passivating all dangling W bonds and Ba creating work function-lowering surface dipoles. Wulff construction analysis reveals that the presence of O and Ba significantly alters the surface energetics and changes the proportions of surface facets present under equilibrium conditions. Analysis of previously published data on W sintering kinetics suggests that fine W particles in the size range of 100-500 nm may be at or near equilibrium during cathode synthesis and thus may exhibit surface orientation fractions well described by the calculated Wulff construction.

  5. Limitations of workers diagnosed with cancer evaluated with Work Role Functioning Questionnaire-Br.

    Science.gov (United States)

    Gallasch, Cristiane H; Alexandre, Neusa Mc; Esteves, Sergio Cb; Gomes, Helena F; da Rocha, Elaine Cl; Baptista, Patricia Cp

    2017-01-01

    The main subject of the current study is to look into the limitations found in individuals diagnosed with cancer, considered a public health problem, especially in developing countries where the impact of this disease is expected to account for 80% of 20 million new cases estimated worldwide by 2025. For some patients undergoing treatment, continuing to be professionally active is challenging especially considering that work fosters a purpose in life, a sense of contribution, distraction, and self-esteem, which aids in physical, cognitive, emotional, and interpersonal recovery. Within this context, the aim is to describe the limitations found in individuals with cancer, who have maintained their work activities in private service during radiotherapy treatment, through a descriptive study and a quantitative approach. The final sample of 51 participants was defined by non-probability convenience sampling, based on information from all patients admitted in that period, with a research protocol approved by the Research Ethics Committee. The assessment using the Brazilian version of the Work Role Functioning Questionnaire showed higher average work functioning indexes for social demand, with an average score of 94.33 (11.47). In turn, the worst indexes were registered in physical demand. No significant differences were observed between groups of treatment protocols in terms of WRFQ-Br scores. The work functioning assessment of workers diagnosed with cancer in radiotherapy using the WRFQ-Br showed higher scores for social demands and lower for physical demands. The preserved social performance may be linked to individual work functioning within the family, at work and, consequently, within society, given that the study included patients who maintained their work activities during the proposed treatment period, highlighting the social role of work for patients with cancer.

  6. The effectiveness of social work services for families whose children are in temporary custody

    Directory of Open Access Journals (Sweden)

    Bardauskiene R.

    2018-01-01

    Full Text Available Despite that there is an operating social support system for families, social workers are affected by factors that limit effectiveness of their activities in working with families whose children are taken into temporary custody. The article aims to uncover what hinders social worker to carry out effective work in providing social services for families whose children are in temporary custody. Qualitative research data shows that the research participants’ awareness of social work effectiveness is limited to its individual components. Putting together these components one can get a broad definition of effectivenessof social work though the research participants themselves donot use such a concept. The research data reveals that micro level factors influencing effectiveness of social workers’ activities working with families whose children are in temporary custody are as follows: absence of parental motivation to seek changes and unfavourable environment as well as negative community approach to social risk families. Macro level factors limiting social work effectiveness working with the families at social risk lie in the system of social services. Inadequate management of social work, limited social workers’ access to resources necessary to restore family functions; too high workload for social workers are essential factors limiting social work effectiveness.

  7. The effect of aerobic exercise training on work ability of midwives working in health care centers

    Directory of Open Access Journals (Sweden)

    Zahra Abedian

    2017-01-01

    Full Text Available Background & aim: Maintaining and improving the work ability are important social goals, which challenge the health care and rehabilitation systems as well as health providers. The physical and mental health status affect the work ability. Regarding this, the current study aimed to investigate the effect of aerobic training on the work ability of the midwives in the health care centers of Mashhad, Iran in 2013. Methods: This randomized clinical trial was conducted on 60 midwives working in the health centers of Mashhad, Iran, using purposeful sampling method. The health care centers were selected randomly, and then assigned into the intervention and control groups. Subsequently, the intervention group performed aerobic exercise for 24 sessions. Data collection was performed using the work ability index and the Bruce test (to compare the fitness of the participants at the pre- and post-intervention stages. For data analysis, the two-way ANOVA, Mann-Whitney U, and Chi-square tests as well as independent and paired sample t-tests were employed, using SPSS version 19. The P-value less than 0.05 was considered statistically significant. Results: According to the results of the study, the mean score of work ability was significantly higher in the intervention group than that in the control group (40.5±4.9 vs. 36.4± 5.3, respectively; P=0.004. Furthermore, there was a significant difference between the two groups regarding the two variables including work ability compared with life time best (P

  8. Responses to work complexity: the novice to expert effect.

    Science.gov (United States)

    Burger, Jeri L; Parker, Karen; Cason, Linda; Hauck, Sheila; Kaetzel, Denise; O'Nan, Cathy; White, Ann

    2010-06-01

    The purpose of this study was to explore the differences in how advanced beginners, competent, and expert nurses prioritize and reprioritize patient care. This qualitative study had a purposive sample of 23 nurses on cardiac/ telemetry units at five hospitals. Four themes emerged from the data: cognitive strategies, communication, integration of roles, and response to the work environment. As the nurses progressed in expertise, they were better able to organize, more effectively deal with interruptions, anticipate patient needs, integrate varied nursing roles into their work, and communicate effectively. The significance of this study is the identification of factors that affect the nurse's ability to work productively in today's care environment. It increases understanding of the graduate nurses' perception and response to the complexity and work of nursing. An understanding of these factors provides the basis for further research to understand and promote transition of nurses from advanced beginner to expert.

  9. Shift work and its effects on the cardiovascular system.

    Science.gov (United States)

    Mosendane, T; Mosendane, T; Raal, F J

    2008-01-01

    The practice of shift-work scheduling has long been part of normal work duties in emergency services such as health and security. It is only recently, in the wake of growing job opportunities and booming industries, where more employees are needed to keep services running over 24-hour periods that studies on the effects of shift work on workers' health have begun to delve deeper. The desynchronisation that occurs in circadian rhythms, with respect to sleep cycles, predisposes employees to coronary heart disease, gastrointestinal disturbances, increased risk of breast cancer and poor pregnancy outcomes. This literature review focuses on circadian rhythms, their molecular components, disturbances of these rhythms as a result of shift work and the adverse effects thereof on the cardiovascular system.

  10. Systematic review of the effect of the psychosocial working environment on cognition and dementia.

    Science.gov (United States)

    Then, Francisca S; Luck, Tobias; Luppa, Melanie; Thinschmidt, Marleen; Deckert, Stefanie; Nieuwenhuijsen, Karen; Seidler, Andreas; Riedel-Heller, Steffi G

    2014-05-01

    The high incidence of cognitive impairment in the ageing population, together with the challenges it imposes to health systems, raises the question of what affect working life has on cognitive abilities. The study, therefore, reviews recent work on the longitudinal impact of psychosocial work conditions on cognitive functioning and on dementia. Relevant articles were identified by a systematic literature search in PubMed and PsycINFO using a standardised search string and specific inclusion and exclusion criteria. We included articles reporting longitudinal effects that were investigated in cohort studies, case-control studies or randomised controlled trials in the working population. Two independent reviewers evaluated the studies in three subsequent phases: (i) title-abstract screening, (ii) full-text screening and (iii) checklist-based quality assessment.Methodical evaluation of the identified articles resulted in 17 studies of adequate quality. We found evidence for a protective effect of high job control and high work complexity with people and data on the risk of cognitive decline and dementia. Moreover, cognitively demanding work conditions seem to be associated with a decreased risk of cognitive deterioration in old age.Psychosocial work conditions can have an impact on cognitive functioning and even on the risk of dementia. As the world of work is undergoing fundamental changes, such as accelerated technological advances and an ageing working population, optimising work conditions is essential in order to promote and maintain cognitive abilities into old age.

  11. Functional organic field-effect transistors.

    Science.gov (United States)

    Guo, Yunlong; Yu, Gui; Liu, Yunqi

    2010-10-25

    Functional organic field-effect transistors (OFETs) have attracted increasing attention in the past few years due to their wide variety of potential applications. Research on functional OFETs underpins future advances in organic electronics. In this review, different types of functional OFETs including organic phototransistors, organic memory FETs, organic light emitting FETs, sensors based on OFETs and other functional OFETs are introduced. In order to provide a comprehensive overview of this field, the history, current status of research, main challenges and prospects for functional OFETs are all discussed.

  12. Is Work-Related Rumination Associated with Deficits in Executive Functioning?

    Science.gov (United States)

    Cropley, Mark; Zijlstra, Fred R H; Querstret, Dawn; Beck, Sarah

    2016-01-01

    Work-related rumination, that is, perseverative thinking about work during leisure time, has been associated with a range of negative health and wellbeing issues. The present paper examined the association between work-related rumination and cognitive processes centerd around the theoretical construct of executive functioning. Executive functioning is an umbrella term for high level cognitive processes such as planning, working memory, inhibition, mental flexibility; and it underlies how people manage and regulate their goal directed behavior. Three studies are reported. Study I, reports the results of a cross-sectional study of 240 employees, and demonstrates significant correlations between work-related rumination and three proxy measures of executive functioning: cognitive failures (0.33), cognitive flexibility (-0.24), and situational awareness at work (-0.28). Study II (n = 939), expands on the findings from study 1 and demonstrates that workers reporting medium and high work-related rumination were 2.8 and 5 times, respectively, more likely to report cognitive failures relative to low ruminators. High ruminators also demonstrated greater difficulties with 'lapses of attention' (OR = 4.8), 'lack of focus of attention' (OR = 3.4), and 'absent mindedness' (OR = 4.3). The final study, examined the association between work-related rumination and executive functioning using interview data from 2460 full time workers. Workers were divided into tertiles low, medium, and high. The findings showed that high work-related rumination was associated with deficits in starting (OR = 2.3) and finishing projects (OR = 2.4), fidgeting (OR = 1.9), memory (OR = 2.2), pursuing tasks in order (OR = 1.8), and feeling compelled to do things (OR = 2.0). It was argued that work-related rumination may not be related to work demands per se, but appears to be an executive functioning/control issue. Such findings are important for the design and delivery of intervention programes aimed at

  13. Emotion perception and executive functioning predict work status in euthymic bipolar disorder.

    Science.gov (United States)

    Ryan, Kelly A; Vederman, Aaron C; Kamali, Masoud; Marshall, David; Weldon, Anne L; McInnis, Melvin G; Langenecker, Scott A

    2013-12-15

    Functional recovery, including return to work, in Bipolar Disorder (BD) lags behind clinical recovery and may be incomplete when acute mood symptoms have subsided. We examined impact of cognition on work status and underemployment in a sample of 156 Euthymic-BD and 143 controls (HC) who were divided into working/not working groups. Clinical, health, social support, and personality data were collected, and eight cognitive factors were derived from a battery of neuropsychological tests. The HC groups outperformed the BD groups on seven of eight cognitive factors. The working-BD group outperformed the not working-BD group on 4 cognitive factors composed of tasks of emotion processing and executive functioning including processing speed and set shifting. Emotion processing and executive tasks were predictive of BD unemployment, after accounting for number of mood episodes. Four cognitive factors accounted for a significant amount of the variance in work status among the BD participants. Results indicate that patients with BD who are unemployed/unable to work exhibit greater difficulties processing emotional information and on executive tasks that comprise a set shifting or interference resolution component as compared to those who are employed, independent of other factors. These cognitive and affective factors are suggested as targets for treatment and/or accommodations. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Microgravity effect on testicular functions.

    Science.gov (United States)

    Ricci, G; Catizone, A; Esposito, R; Galdieri, M

    2004-07-01

    In mammals spaceflight influences spermatogenesis since spermatogonial germ cell proliferation, compared to synchronous controls, is lightly decreased in irradiated or flown rats. Moreover, changes of the plasmatic testosterone production was described either in flight rats, or in rats maintained in simulated microgravity conditions. The hormonal levels of the astronauts change as it has been previously described, including hormones involved in the regulation of spermatogenesis such as testosterone and luteinizing hormone (LH). In microgravity conditions, human testosterone levels decreased whereas circulating LH levels increased. To study the effect of simulated microgravity on mammalian spermatogenesis we have utilized the Rotary Cell Culture System (RCCS) and we have cultured testicular fragments isolated from prepuberal rats in a chemically defined medium for three days under microgravity conditions. As control we have cultured the same amount of fragments at unit gravity. The morphology of the samples has been studied and the number of proliferating cells has been counted in control samples and in samples maintained in RCCS. The results indicate that the number of duplicating cells in the tubules was significantly increased in the microgravity-cultured fragments. The amount of testosterone secreted in the culture medium has been also evaluated and in RCCS samples the amount of the hormone was higher respect to the control samples.

  15. Variation in the thermionic work function of semiconductor powders exposed to electromagnetic radiation

    Science.gov (United States)

    Bourasseau, S.; Martin, J. R.; Juillet, F.; Teichner, S. J.

    1977-01-01

    The study of the variation of thermoelectronic work function potential of TiO2 in the presence of isobutane shows that this gas is not adsorbed on this solid, in either the presence or the absence of ultraviolet radiation. These results, as well as those obtained in a previous work, lead to the mechanism of the photo-oxidation of isobutane at room temperature, in which excited atomic oxygen is the active species.

  16. Intensive Working Memory Training Produces Functional Changes in Large-scale Frontoparietal Networks.

    Science.gov (United States)

    Thompson, Todd W; Waskom, Michael L; Gabrieli, John D E

    2016-04-01

    Working memory is central to human cognition, and intensive cognitive training has been shown to expand working memory capacity in a given domain. It remains unknown, however, how the neural systems that support working memory are altered through intensive training to enable the expansion of working memory capacity. We used fMRI to measure plasticity in activations associated with complex working memory before and after 20 days of training. Healthy young adults were randomly assigned to train on either a dual n-back working memory task or a demanding visuospatial attention task. Training resulted in substantial and task-specific expansion of dual n-back abilities accompanied by changes in the relationship between working memory load and activation. Training differentially affected activations in two large-scale frontoparietal networks thought to underlie working memory: the executive control network and the dorsal attention network. Activations in both networks linearly scaled with working memory load before training, but training dissociated the role of the two networks and eliminated this relationship in the executive control network. Load-dependent functional connectivity both within and between these two networks increased following training, and the magnitudes of increased connectivity were positively correlated with improvements in task performance. These results provide insight into the adaptive neural systems that underlie large gains in working memory capacity through training.

  17. The cost of misremembering: Inferring the loss function in visual working memory.

    Science.gov (United States)

    Sims, Chris R

    2015-03-04

    Visual working memory (VWM) is a highly limited storage system. A basic consequence of this fact is that visual memories cannot perfectly encode or represent the veridical structure of the world. However, in natural tasks, some memory errors might be more costly than others. This raises the intriguing possibility that the nature of memory error reflects the costs of committing different kinds of errors. Many existing theories assume that visual memories are noise-corrupted versions of afferent perceptual signals. However, this additive noise assumption oversimplifies the problem. Implicit in the behavioral phenomena of visual working memory is the concept of a loss function: a mathematical entity that describes the relative cost to the organism of making different types of memory errors. An optimally efficient memory system is one that minimizes the expected loss according to a particular loss function, while subject to a constraint on memory capacity. This paper describes a novel theoretical framework for characterizing visual working memory in terms of its implicit loss function. Using inverse decision theory, the empirical loss function is estimated from the results of a standard delayed recall visual memory experiment. These results are compared to the predicted behavior of a visual working memory system that is optimally efficient for a previously identified natural task, gaze correction following saccadic error. Finally, the approach is compared to alternative models of visual working memory, and shown to offer a superior account of the empirical data across a range of experimental datasets. © 2015 ARVO.

  18. The effect of functional compensation among duplicate genes can ...

    Indian Academy of Sciences (India)

    [Bozorgmehr J. E. H. 2012 The effect of functional compensation among duplicate genes can constrain their evolutionary divergence. J. Genet. 91, 1–8] ... gene can provide a molecular substrate for evolution to work on under a relaxed ...... orthology, paralogy, and conserved synteny for dog and human. PLoS Comput. Biol ...

  19. Functional connectivity among spike trains in neural assemblies during rat working memory task.

    Science.gov (United States)

    Xie, Jiacun; Bai, Wenwen; Liu, Tiaotiao; Tian, Xin

    2014-11-01

    Working memory refers to a brain system that provides temporary storage to manipulate information for complex cognitive tasks. As the brain is a more complex, dynamic and interwoven network of connections and interactions, the questions raised here: how to investigate the mechanism of working memory from the view of functional connectivity in brain network? How to present most characteristic features of functional connectivity in a low-dimensional network? To address these questions, we recorded the spike trains in prefrontal cortex with multi-electrodes when rats performed a working memory task in Y-maze. The functional connectivity matrix among spike trains was calculated via maximum likelihood estimation (MLE). The average connectivity value Cc, mean of the matrix, was calculated and used to describe connectivity strength quantitatively. The spike network was constructed by the functional connectivity matrix. The information transfer efficiency Eglob was calculated and used to present the features of the network. In order to establish a low-dimensional spike network, the active neurons with higher firing rates than average rate were selected based on sparse coding. The results show that the connectivity Cc and the network transfer efficiency Eglob vaired with time during the task. The maximum values of Cc and Eglob were prior to the working memory behavior reference point. Comparing with the results in the original network, the feature network could present more characteristic features of functional connectivity. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. On the work function and the charging of small ( r ≤ 5 nm) nanoparticles in plasmas

    Science.gov (United States)

    Kalered, E.; Brenning, N.; Pilch, I.; Caillault, L.; Minéa, T.; Ojamäe, L.

    2017-01-01

    The growth of nanoparticles (NPs) in plasmas is an attractive technique where improved theoretical understanding is needed for quantitative modeling. The variation of the work function W with size for small NPs, rN P≤ 5 nm, is a key quantity for modeling of three NP charging processes that become increasingly important at a smaller size: electron field emission, thermionic electron emission, and electron impact detachment. Here we report the theoretical values of the work function in this size range. Density functional theory is used to calculate the work functions for a set of NP charge numbers, sizes, and shapes, using copper for a case study. An analytical approximation is shown to give quite accurate work functions provided that rN P > 0.4 nm, i.e., consisting of about >20 atoms, and provided also that the NPs have relaxed close to spherical shape. For smaller sizes, W deviates from the approximation, and also depends on the charge number. Some consequences of these results for nanoparticle charging are outlined. In particular, a decrease in W for NP radius below about 1 nm has fundamental consequences for their charge in a plasma environment, and thereby on the important processes of NP nucleation, early growth, and agglomeration.

  1. The Reciprocal Effect of Psychosocial Aspects on Nurses' Working Conditions.

    Science.gov (United States)

    Kowalczuk, Krystyna; Krajewska-Kułak, Elżbieta; Sobolewski, Marek

    2017-01-01

    Objectives: Psychosocial work risks are most often considered in the context of occupational stress. The aim of this article is to evaluate the correlations between different aspects of nurses' psychosocial working conditions. Materials and Methods: The study was conducted using the questionnaire: Psychosocial aspects of work. A total of 789 nurses working in inpatient health care facilities in Bialystok were included in the study. Correlation analysis was performed by determining Spearman's correlation coefficient. Results: Correlations between the primary scales, such as job demands, control, social support, well-being, and expectations of changes, were evaluated. The weakest correlation was shown between the assessment of job demands and other work aspects. The strongest correlation was found between the ability to control and social support. Perception of the need for changes was influenced by the assessment of job demands, components of the control scale and, most of all, the scale of social support. A strong correlation was found between physical and psychological well-being and support from superiors and coworkers. Conclusions: The state of well-being had no effects on nurses' assessment of the demands they were faced with. Nurses' well-being depended only on social support provided by their superiors and colleagues, the sense of being able to have an effect on the performed work, minimal conflicts, and absence of overload.Management should enable adequate working conditions in order to ensure nurses' physical and psychological well-being, as both these aspects were closely correlated.Poor social support, lack of a sense of control over one's work, conflicts, and work overload were factors that promoted nurses' expectations of changes.

  2. The Reciprocal Effect of Psychosocial Aspects on Nurses' Working Conditions

    Directory of Open Access Journals (Sweden)

    Krystyna Kowalczuk

    2017-08-01

    Full Text Available Objectives: Psychosocial work risks are most often considered in the context of occupational stress. The aim of this article is to evaluate the correlations between different aspects of nurses' psychosocial working conditions.Materials and Methods: The study was conducted using the questionnaire: Psychosocial aspects of work. A total of 789 nurses working in inpatient health care facilities in Bialystok were included in the study. Correlation analysis was performed by determining Spearman's correlation coefficient.Results: Correlations between the primary scales, such as job demands, control, social support, well-being, and expectations of changes, were evaluated. The weakest correlation was shown between the assessment of job demands and other work aspects. The strongest correlation was found between the ability to control and social support. Perception of the need for changes was influenced by the assessment of job demands, components of the control scale and, most of all, the scale of social support. A strong correlation was found between physical and psychological well-being and support from superiors and coworkers.Conclusions:The state of well-being had no effects on nurses' assessment of the demands they were faced with. Nurses' well-being depended only on social support provided by their superiors and colleagues, the sense of being able to have an effect on the performed work, minimal conflicts, and absence of overload.Management should enable adequate working conditions in order to ensure nurses' physical and psychological well-being, as both these aspects were closely correlated.Poor social support, lack of a sense of control over one's work, conflicts, and work overload were factors that promoted nurses' expectations of changes.

  3. Expertise, Working Memory and Articulatory Suppression Effect: Their Relation with Simultaneous Interpreting Performance.

    Science.gov (United States)

    Injoque-Ricle, Irene; Barreyro, Juan Pablo; Formoso, Jesica; Jaichenco, Virginia I

    2015-01-01

    Simultaneous interpreting is a complex bilingual verbal activity that involves the auditory perception of an oral communication and the production of a coherent discourse. One of the cognitive functions underlying simultaneous interpreting is working memory. The aim of this work was to study the relationship between expertise, working memory capacity and articulatory suppression effect, and the ability to perform simultaneous interpreting. For this purpose, four working memory tasks and one simultaneous interpreting task were administered to thirty Spanish-speaking professional English interpreters. Results showed that simultaneous interpreting ability might be supported by the working memory´s capacity to store or process information, but also by the ability of the interpreter to cope with the articulatory suppression effect. We conclude that interpreters may have or develop resources to support the effect caused by articulatory suppression.

  4. Effects of posture on postoperative pulmonary function

    DEFF Research Database (Denmark)

    Nielsen, K G; Holte, Kathrine; Kehlet, H

    2003-01-01

    BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed....... METHODS: Review of controlled, clinical trials evaluating postoperative pulmonary function in patients positioned in the supine vs. the sitting or standing position and patients positioned in the supine vs. the lateral position. Data were obtained from a search in the Medline and Cochrane databases (1966...... effect on postoperative pulmonary function in the sitting or standing position compared with the supine. Thus, avoidance of the supine position may improve postoperative pulmonary function. Three of six studies showed a positive effect on postoperative pulmonary function of the lateral side compared...

  5. Working memory as a predictor of negative symptoms and functional outcome in first episode psychosis.

    Science.gov (United States)

    González-Ortega, Itxaso; de Los Mozos, Vanesa; Echeburúa, Enrique; Mezo, Maria; Besga, Ariadna; Ruiz de Azúa, Sonia; González-Pinto, Asunción; Gutierrez, Miguel; Zorrilla, Iñaki; González-Pinto, Ana

    2013-03-30

    The relationship of neurocognitive course with clinical and functional outcomes in psychosis is not well known, especially in the long term. The aim of the study was to examine the clinical and neuropsychological course of first-episode psychosis patients at 5-year follow-up and analyze the relationship of cognitive performance with clinical and functional outcome. The 5-year follow-up was conducted with 26 first-episode psychosis patients. Psychotic symptoms were measured by the Positive and Negative Syndrome Scale, manic and depressive symptoms by the Young Mania Rating Scale and Hamilton Depression Rating Scale respectively, and psychosocial functioning by the Functioning Assessment Short Test. The cognitive domains were assessed by the Wechsler Adult Intelligence Scale, the Wisconsin Card Sorting Test, the Trail Making Test, the Verbal Fluency Test, the Stroop Colour-Word Test and the Wechsler Memory Scale. Patients showed symptomatic improvement in the follow-up except in negative psychotic symptoms. There was also improvement in most cognitive domains except in working memory and processing speed in the follow-up. Working memory impairment was associated to negative psychotic symptoms and poor functional outcomes. Negative symptoms mediated the relationship between working memory and outcome. Therefore, negative symptoms should be a primary target of treatment to improve functional outcomes. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. An energy-efficient intrinsic functional organization of human working memory: A resting-state functional connectivity study.

    Science.gov (United States)

    Liu, Huaigui; Yu, Hongxu; Li, Yanjun; Qin, Wen; Xu, Lixue; Yu, Chunshui; Liang, Meng

    2017-01-01

    Working memory (WM) is the active maintenance of currently relevant information that was just experienced or retrieved from long-term memory but no longer exists in the external environment; however, the intrinsic functional organization of the brain underlying human WM performance remains largely unknown. We hypothesize that the intrinsic functional organization of human WM is an energy-efficient system. We tested this hypothesis by analyzing associations between WM performance (reaction times of correct responses) at different task difficulties (2-back and 3-back tasks) and the resting-state functional connectivity density (FCD) and strength (FCS) in 282 healthy young adults. Voxel-based FCD analysis showed that the reaction times were negatively correlated with the FCD values of several brain regions known to be engaged in WM performance: the right inferior parietal lobule and inferior frontal gyrus for both the 2-back and the 3-back tasks and the right superior parietal lobule, supramarginal gyrus, left inferior parietal lobule and bilateral middle occipital gyrus for the 3-back task. Further analyses showed that the FCS values of these regions with several frontal, parietal and occipital regions were also negatively correlated with the reaction times; the 3-back task was associated with much more functional connections than the 2-back task. These findings suggest that the intrinsic working memory network is an energy-efficient and hierarchical system. A simple working memory task is controlled only by the core subsystem; however, a complex working memory task is associated with more nodes and connections of the system. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Isolation, purification and effects of hypoglycemic functional ...

    African Journals Online (AJOL)

    Isolation, purification and effects of hypoglycemic functional polysaccharides from Inonotus obliquus. Tao Hu, Ping Liu, Yuanying Ni, Chuntao Lu. Abstract. Inonotus obliquus is generally used for the treatment of diseases such as cancers, angiocardiopathy and diabetes. However, few studies are available on its functional ...

  8. Work environments and organizational effectiveness: A call for integration

    Energy Technology Data Exchange (ETDEWEB)

    Heerwagen, J.H.; Heubach, J.G.; Brown, B.W.; Sanchez, J.A.; Montgomery, J.C.; Weimer, W.C.

    1994-07-01

    In response to a request from the Pacific Northwest Laboratory`s Analytical Chemistry Upgrades Program, a team was formed to (1) review work environment and productivity research, (2) report the research in a manner usable to organizational decision-makers, (3) identify Hanford Site facilities examples of the work environment principles and research, and (4) publish the review results in a referred journal. This report summarizes the work environment-organizational effectiveness research reviewed, provides the foundation for a publishable article, and outlines the integration of work environment research and organizational effectiveness in continuing improvement programs and strategic planning. The research cited in this review shows that the physical work environment offers a valuable tool that, used wisely, can contribute significantly to the performance of an organization, its bottom-line economics, and the well-being of all of its employees. This finding leads to one central recommendation: to derive the maximum benefit to the corporation, managers and designers must integrate organizational goals and programs with work environment design. While much of the research cited focuses on office environments, the results and design principles and practices are relevant to a full range of settings: laboratories, schools, hospitals, and factories. The major findings of the research reviewed are summarized below in four areas: (1) performance, (2) well-being, (3) image, and (4) turnover and recruitment.

  9. Spatial working memory in children with high-functioning autism: intact configural processing but impaired capacity.

    Science.gov (United States)

    Jiang, Yuhong V; Capistrano, Christian G; Palm, Bryce E

    2014-02-01

    Visual attention and visual working memory exert severe capacity limitations on cognitive processing. Impairments in both functions may exacerbate the social and communication deficits seen in children with an autism spectrum disorder (ASD). This study characterizes spatial working memory and visual attention in school-age children with high-functioning autism. Children with ASD, and age, gender, and IQ-matched typically developing (TD) children performed 2 tasks: a spatial working memory task and an attentive tracking task. Compared with TD children, children with ASD showed a more pronounced deficit in the spatial working memory task than the attentive tracking task, even though the latter placed significant demands on sustained attention, location updating, and distractor inhibition. Because both groups of children were sensitive to configuration mismatches between the sample and test arrays, the spatial working memory deficit was not because of atypical organization of spatial working memory. These findings show that attention and working memory are dissociable, and that children with ASD show a specific deficit in buffering visual information across temporal discontinuity. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  10. Social anhedonia and work and social functioning in the acute and recovered phases of eating disorders.

    Science.gov (United States)

    Harrison, Amy; Mountford, Victoria A; Tchanturia, Kate

    2014-08-15

    Interpersonal difficulties are proposed to maintain eating disorders (EDs). This study explored whether social anhedonia (SA) was an additional social emotional maintenance factor which might also explain work/social problems in EDs. Additionally, the study explored SA and work and social adjustment in recovered participants. Women with anorexia nervosa (AN; n=105), bulimia nervosa (BN; n=46), recovered from AN (RAN; n=30) and non-ED controls (n=136) completed the Work and Social Adjustment Scale (WSAS) and the Revised Social Anhedonia Scale. ED participants reported greater SA and WSAS scores than non-ED controls; the RAN group reported an intermediate profile. AN participants had poorer work/social adjustment than BN participants. SA was associated with longer illness duration. SA, current severity (BMI) and lifetime severity (lowest adult BMI) significantly predicted work/social difficulties. Recovered participants scoring in the clinical range for SA experienced significantly greater work/social difficulties than recovered participants scoring outside the clinical range for SA. EDs are associated with clinical levels of SA and poor work/social functioning which reduce in recovery. SA may maintain the interpersonal functioning difficulties. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Work stress, anthropometry, lung function, blood pressure, and blood-based biomarkers

    DEFF Research Database (Denmark)

    Magnusson Hanson, Linda L.; Westerlund, Hugo; Goldberg, Marcel

    2017-01-01

    -based biomarkers. Linear regression analyses before and after multivariable adjustment for age, socioeconomic status, depressive symptoms, health-related behaviours, and chronic conditions showed that work stress was associated with higher BMI, waist circumference, waist-hip ratio, alanine transaminase, white......, creatinine, glucose levels or resting blood pressure measures. This indicates that work stress is associated altered metabolic profile, increased systemic inflammation, and, in men, poorer liver function, which is a marker of high alcohol consumption.......Work stress is a risk factor for cardio-metabolic diseases, but few large-scale studies have examined the clinical profile of individuals with work stress. To address this limitation, we conducted a cross-sectional study including 43,593 working adults from a French population-based sample aged 18...

  12. The impact of supported employment and working on clinical and social functioning: results of an international study of individual placement and support.

    Science.gov (United States)

    Burns, Tom; Catty, Jocelyn; White, Sarah; Becker, Thomas; Koletsi, Marsha; Fioritti, Angelo; Rössler, Wulf; Tomov, Toma; van Busschbach, Jooske; Wiersma, Durk; Lauber, Christoph

    2009-09-01

    Concerns are frequently expressed that working might worsen the mental health of people with severe mental illness (SMI). Several studies of Individual Placement and Support (IPS), however, have found associations between working and better nonvocational outcomes. IPS has been found to double the return to work of people with SMI in 6 European countries. To explore separately associations between IPS, returning to work, and clinical and social outcomes. Patients (n = 312) in a randomized controlled trial of IPS in 6 European centers were followed up for 18 months. There were no differences in clinical and social functioning between IPS and control patients at 18 months. Those who worked had better global functioning, fewer symptoms, and less social disability at final follow-up; greater job tenure was associated with better functioning. Working was associated with concurrently better clinical and social functioning, but this contrast was stronger in the control group, suggesting that IPS was better than the control service at helping more unwell patients into work. Working was associated with having been in remission and out of hospital for the previous 6 months. It was also associated with a slight decrease in depression and with being in remission over the subsequent 6 months. Concerns among clinicians about possible detrimental effects of working and supported employment have been misplaced. Although some of the associations found may have been selection effects, there is sufficient evidence of work having beneficial effects on clinical and social functioning to merit further exploration.

  13. Knowledge work productivity effect on quality of knowledge work in software development process in SME

    Science.gov (United States)

    Yusoff, Mohd Zairol; Mahmuddin, Massudi; Ahmad, Mazida

    2016-08-01

    Knowledge and skill are necessary to develop the capability of knowledge workers. However, there is very little understanding of what the necessary knowledge work (KW) is, and how they influence the quality of knowledge work or knowledge work productivity (KWP) in software development process, including that in small and medium-sized (SME) enterprise. The SME constitutes a major part of the economy and it has been relatively unsuccessful in developing KWP. Accordingly, this paper seeks to explore the influencing dimensions of KWP that effect on the quality of KW in SME environment. First, based on the analysis of the existing literatures, the key characteristics of KW productivity are defined. Second, the conceptual model is proposed, which explores the dimensions of the KWP and its quality. This study analyses data collected from 150 respondents (based on [1], who involve in SME in Malaysia and validates the models by using structural equation modeling (SEM). The results provide an analysis of the effect of KWP on the quality of KW and business success, and have a significant relevance for both research and practice in the SME

  14. Wage, work environment, and staffing: effects on nurse outcomes.

    Science.gov (United States)

    McHugh, Matthew D; Ma, Chenjuan

    2014-01-01

    Research has shown that hospitals with better nurse staffing and work environments have better nurse outcomes-less burnout, job dissatisfaction, and intention to leave the job. Many studies, however, have not accounted for wage effects, which may confound findings. By using a secondary analysis with cross-sectional administrative data and a four-state survey of nurses, we investigated how wage, work environment, and staffing were associated with nurse outcomes. Logistic regression models, with and without wage, were used to estimate the effects of work environment and staffing on burnout, job dissatisfaction, and intent to leave. We discovered that wage was associated with job dissatisfaction and intent to leave but had little influence on burnout, while work environment and average patient-to-nurse ratio still have considerable effects on nurse outcomes. Wage is important for good nurse outcomes, but it does not diminish the significant influence of work environment and staffing on nurse outcomes. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  15. Improving meat cutters' work: changes and effects following an intervention.

    Science.gov (United States)

    Vogel, K; Karltun, J; Eklund, J; Engkvist, I-L

    2013-11-01

    Meat cutters face higher risks of injury and musculoskeletal problems than most other occupational groups. The aims of this paper were to describe ergonomics changes implemented in three meat cutting plants and to evaluate effects related to ergonomics on the individual meat cutters and their work. Data was collected by interviews, observations, document studies and a questionnaire (n = 247), as a post intervention study. The changes implemented consisted of reducing knife work to a maximum of 6 h per day and introducing a job rotation scheme with work periods of equal length. Tasks other than traditional meat cutting were added. A competence development plan for each meat cutter and easy adjustment of workplace height were introduced. The questionnaire showed a reduction in perceived physical work load. In general, the changes were perceived positively. Figures from the company showed a positive trend for injuries and sick leave. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. An Empirical Study on the Effect of Work/Life Commitment to Work-Life Conflict

    Science.gov (United States)

    Ma, Li; Yin, Jie-lin

    This study examined the relation between work and life orientation and work interfere with personal life or personal life interfere with work of employees in China. Cluster analysis results showed that there are four profiles of orientation: work orientation, life orientation, integration and disengagement orientation. There are significant differences in work interfere personal life and personal life interfere work between different profiles.

  17. Magnetic tunnel contacts to silicon with low-work-function ytterbium nanolayers

    NARCIS (Netherlands)

    Patel, R.S.; Dash, S.P.; de Jong, Machiel Pieter; Jansen, R.

    2009-01-01

    Unambiguous proof of spin transport in semiconductor spintronic devices requires a control experiment to exclude spurious signals that arise from the presence of the ferromagnetic contacts. It is shown here that insertion of a low-work-function Yb nanolayer in ferromagnetic tunnel contacts to

  18. Functional Differentiation of Job Demands: Dilemmas Confronting the Continuum in Social Work Education.

    Science.gov (United States)

    Kolevzon, Michael S.; Biggerstaff, Marilyn A.

    1983-01-01

    In a survey comparing 22 work activities of BA, BSW, and MSW social workers, little functional differentiation was found between BAs and BSWs, and significant differentiation was found between BSWs and MSWs on at least half of the activities studied. Intervening variables and implications for BSW curricula are discussed. (MSE)

  19. High work function transparent middle electrode for organic tandem solar cells

    NARCIS (Netherlands)

    Moet, D. J. D.; de Bruyn, P.; Blom, P. W. M.

    2010-01-01

    The use of poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) in combination with ZnO as middle electrode in solution-processed organic tandem solar cells requires a pH modification of the PEDOT:PSS dispersion. We demonstrate that this neutralization leads to a reduced work function

  20. Functional specialization of the left ventral parietal cortex in working memory

    Directory of Open Access Journals (Sweden)

    Jennifer Lou Langel

    2014-06-01

    Full Text Available The function of the ventral parietal cortex (VPC is subject to much debate. Many studies suggest a lateralization of function in the VPC, with the left hemisphere facilitating verbal working memory and the right subserving stimulus-driven attention. However, many attentional tasks elicit activity in the VPC bilaterally. To elucidate the potential divides across the VPC in function, we assessed the pattern of activity in the VPC bilaterally across two tasks that require different demands, an oddball attentional task with low working memory demands and a working memory task. An anterior region of the VPC was bilaterally active during novel targets in the oddball task and during retrieval in WM, while more posterior regions of the VPC displayed dissociable functions in the left and right hemisphere, with the left being active during the encoding and retrieval of WM, but not during the oddball task and the right showing the reverse pattern. These results suggest that bilateral regions of the anterior VPC subserve non-mnemonic processes, such as stimulus-driven attention during WM retrieval and oddball detection. The left posterior VPC may be important for speech-related processing important for both working memory and perception, while the right hemisphere is more lateralized for attention.

  1. Ab initio and work function and surface energy anisotropy of LaB6

    NARCIS (Netherlands)

    Uijttewaal, M. A.; de Wijs, G. A.; de Groot, R. A.

    2006-01-01

    Lanthanum hexaboride is one of the cathode materials most used in high-power electronics technology, but the many experimental results do not provide a consistent picture of the surface properties. Therefore, we report the first ab initio calculations of the work functions and surface energies of

  2. Recovery to Preinterventional Functioning, Return-to-Work, and Life Satisfaction After Treatment of Unruptured Aneurysms

    NARCIS (Netherlands)

    Backes, D.; Rinkel, G.J.; Van der Schaaf, I.C.; Bijvank, J.A.; Verweij, B.H.; Visser-Meily, J.M.A.; Post, Marcel W.M.; Algra, A.; Vergouwen, M.D.

    Background and Purpose—The eventual goal of preventive treatment of unruptured intracranial aneurysms is to increase the number of life years with high life satisfaction. Insight in the time with reduced functioning, working capacity, and life satisfaction after aneurysm treatment is pivotal to

  3. Utility of the International Classification of Functioning, Disability and Health (ICF) for Educational Psychologists' Work

    Science.gov (United States)

    Aljunied, Mariam; Frederickson, Norah

    2014-01-01

    Despite embracing a bio-psycho-social perspective, the World Health Organization's International Classification of Functioning, Disability and Health (ICF) assessment framework has had limited application to date with children who have special educational needs (SEN). This study examines its utility for educational psychologists' work with…

  4. Transposition of provisions of the Recast Directive on the functioning of the European Works Council

    NARCIS (Netherlands)

    Cremers, Jan; Lorber, Pascale; Jagodzinski, Romuald

    2015-01-01

    The aim of this chapter is to list selected broader legal provisions and key conditions that can contribute to an improved environment for EWC work and thus stimulate improved functioning of this European body (sine qua non conditions), although an analysis of several of these broader concepts is

  5. A COGNITIVE-BEHAVIOURAL GROUP TREATMENT IMPROVED WORK ABILITY IN PATIENTS WITH SEVERE FUNCTIONAL SOMATIC SYNDROMES

    DEFF Research Database (Denmark)

    Schröder, Andreas; Ørnbøl, Eva; Jensen, Jens Søndergaard

    2014-01-01

    Objective: Functional somatic syndromes (FSS) such as fibromyalgia, irritable bowel and chronic fatigue syndrome often disrupt employment and may lead to long-term dependence on social benefits and permanently reduced work ability. Cognitive-behavioural treatments (CBT) relief symptoms and improve...

  6. Intellectual Growth in Children as a Function of Domain Specific and Domain General Working Memory Subgroups

    Science.gov (United States)

    Swanson, H. Lee

    2011-01-01

    This study examined whether children's growth on measures of fluid (Raven Colored Progressive Matrices) and crystallized (reading and math achievement) intelligence was attributable to domain-specific or domain-general functions of working memory (WM). A sample of 290 elementary school children was tested on measures of intelligence across three…

  7. Does work-related training reduce the discrepancy between function requirements and competencies?

    NARCIS (Netherlands)

    E.R. Kappe; G.E. Bijwaard (Govert)

    2005-01-01

    textabstractThe issue of lifelong learning is high on the political agenda. However, despite this political interest and the large economic literature on human capital, the impact of work-related training on the discrepancy between function requirements and the skills of the employee has been

  8. The Influence of Domain Knowledge on the Functional Capacity of Working Memory

    Science.gov (United States)

    Ricks, Travis Rex; Wiley, Jennifer

    2009-01-01

    Theories of expertise have proposed that superior cognitive performance is in part due to increases in the functional capacity of working memory during domain-related tasks. Consistent with this approach Fincher-Kiefer et al. (1988), found that domain knowledge increased scores on baseball-related reading span tasks. The present studies extended…

  9. Sleep disturbances and reduced work functioning in depressive or anxiety disorders

    NARCIS (Netherlands)

    van Mill, Josine G.; Vogelzangs, Nicole; Hoogendijk, Witte J. G.; Penninx, Brenda W. J. H.

    2013-01-01

    Objectives: We aimed to examine the associations between sleep disturbances and work functioning in an epidemiologic cohort study in subjects with or without depressive or anxiety disorders. Methods: There were 707 subjects included in our analyses with depressive or anxiety disorders and 728

  10. Self-Regulation, Executive Function, Working Memory, and Academic Achievement of Female High School Students

    Science.gov (United States)

    Halloran, Roberta Kathryn

    2011-01-01

    Self-regulation, executive function and working memory are areas of cognitive processing that have been studied extensively. Although many studies have examined the constructs, there is limited empirical support suggesting a formal link between the three cognitive processes and their prediction of academic achievement. Thus, the present study…

  11. Effects of Skill Training on Working Memory Capacity

    Science.gov (United States)

    Lee, Yuh-shiow; Lu, Min-ju; Ko, Hsiu-ping

    2007-01-01

    In this study we examined the effects of skill training, in particular mental abacus and music training, on working memory. Two groups of participants--children who had received mental abacus training and their controls--participated in Experiment 1. All participants performed the following span tasks: forward digit span, backward digit span,…

  12. Managerial Effectiveness: Impact of Emotional Intelligence and Work ...

    African Journals Online (AJOL)

    in this study are: Emotional Intelligence Scale, Work-Family Role Conflict Scale and Managerial Effectiveness Scale. Linear Regression Analysis was used to test hypotheses that were generated for the study at 0.05 alpha levels. Finding reveals that there was a significant combined contribution of emotional intelligence and ...

  13. The Effects of Integrating Laboratory Work with Theory on Academic ...

    African Journals Online (AJOL)

    This study was an attempt to investigate the effects of integrating laboratory work with theory on academic achievement of secondary school physics students. The study was conducted in Oron Local Government Area of Akwa Ibom State, Nigeria. A total of one hundred and sixty two (162) senior secondary two (SS2) physics ...

  14. Path Analysis of Empowerment and Work Effectiveness among Staff Nurses

    National Research Council Canada - National Science Library

    Eo, Yong-Sook; Kim, Young-Hae; Lee, Nae-Young

    2014-01-01

    .... In practice, improving nursing work effectiveness directly relates to increasing a hospital's competitiveness. With regard to performance-based pay systems, factors found to affect organizational performance are perceived compensation justice (e.g., organizational justice & compensation equity; Kim & Park, 2006 ) and job characteristics (e.g....

  15. Working Paper 4: Institutions for Effective Water Demand Management

    International Development Research Centre (IDRC) Digital Library (Canada)

    2012-01-23

    Jan 23, 2012 ... This working paper is part of WaDImena 's four Research Series on Water Demand Management, and aims to identify the institutional characteristics necessary for more effective WDM implementation. Exogenous and endogenous factors that may influence an institution's structure and mandate are ...

  16. Working Paper 4: Institutions for Effective Water Demand ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-14

    Dec 14, 2010 ... This working paper is part of WaDImena 's four Research Series on Water Demand Management, and aims to identify the institutional characteristics necessary for more effective WDM implementation. Exogenous and endogenous factors that may influence an institution's structure and mandate are ...

  17. Does Working Memory Impact Functional Outcomes in Individuals With ADHD: A Qualitative and Comprehensive Literature Review.

    Science.gov (United States)

    Fried, Ronna; Abrams, Jessica; Hall, Anna; Feinberg, Leah; Pope, Amanda; Biederman, Joseph

    2017-09-01

    Working Memory (WM) is a domain of executive functioning often impaired in individuals with ADHD. Although assumed to cause difficulties across functioning, the scope of impairments from WM deficits in ADHD has not been investigated. The aim of this study was to examine outcomes associated with WM deficits in ADHD. We conducted a search of the scientific literature on WM deficits, and Freedom From Distractibility (FFD), in ADHD using PubMed and PsycInfo databases. The final sample included 11 controlled studies of WM/FFD deficits in ADHD with operationalized assessment of outcomes in academic, social, and emotional areas. WM assessment was divided into auditory-verbal memory (AVM) and spatial-visual memory (SWM). Seven studies examined WM deficits in academic functioning, eight studies assessed WM deficits in social functioning, and three assessed WM deficits in psychopathology. The majority of the literature suggests that WM deficits affect primarily academic functioning.

  18. Effects of dopamine-related gene-gene interactions on working memory component processes.

    Science.gov (United States)

    Stelzel, Christine; Basten, Ulrike; Montag, Christian; Reuter, Martin; Fiebach, Christian J

    2009-03-01

    Dopamine modulates complex cognitive functions like working memory and cognitive control. It is widely accepted that an optimal level of prefrontal dopamine supports working memory performance. In the present study we used a molecular genetic approach to test whether the optimal activity of the dopamine system for different component processes of working memory is additionally related to the availability of dopamine D2 receptors. We sought evidence for this assumption by investigating the interaction effect (epistasis) of variations in two dopaminergic candidate genes: the catechol-O-methyltransferase (COMT) Val(158)Met polymorphism, which has been shown to influence prefrontal dopamine concentration, and the DRD2/ANKK1-Taq-Ia polymorphism, which has been related to the density of D2 receptors. Our results show that COMT effects on working memory performance are modulated by the DRD2/ANKK1-TAQ-Ia polymorphism and the specific working memory component process under investigation. Val-participants--supposedly characterized by increased prefrontal dopamine concentrations--outperformed Val+ participants in the manipulation of working memory contents, but only when D2 receptor density could be considered to be high. No such effect was present for passive maintenance of working memory contents or for maintenance in the face of distracting information. This beneficial effect of a balance between prefrontal dopamine availability and D2 receptor density reveals the importance of considering epistasis effects and different working memory subprocesses in genetic association studies.

  19. Work distribution function for a Brownian particle driven by a nonconservative force

    Science.gov (United States)

    Saha, Bappa; Mukherji, Sutapa

    2015-06-01

    We derive the distribution function of work performed by a harmonic force acting on a uniformly dragged Brownian particle subjected to a rotational torque. Following the Onsager and Machlup's functional integral approach, we obtain the transition probability of finding the Brownian particle at a particular position at time t given that it started the journey from a specific location at an earlier time. The difference between the forward and the time-reversed form of the generalized Onsager-Machlup's Lagrangian is identified as the rate of medium entropy production which further helps us develop the stochastic thermodynamics formalism for our model. The probability distribution for the work done by the harmonic trap is evaluated for an equilibrium initial condition. Although this distribution has a Gaussian form, it is found that the distribution does not satisfy the conventional work fluctuation theorem.

  20. Pulmonary function tests and work-related respiratory and allergic symptoms in Iranian bakers.

    Science.gov (United States)

    Boskabady, Mohammad Hosein; Taheri, Ehsan; Ahmadi, Sina; Ebrahimi, Kolsoumeh; Soudaneh, Malihe; Mohammadi, Fatemeh; Sabourhasanzadeh, Alireza

    2009-06-01

    Bakers are frequently exposed to various irritant chemicals during work which can induce respiratory problems. In this study, pulmonary function tests and self-reported respiratory and allergic symptoms in bakers were compared with matched control subjects. The frequency of respiratory and allergic symptoms was evaluated in a sample of 58 Iranian bakers and 58 control subjects using a questionnaire. Pulmonary function tests (PFT) were also measured in all participants. All respiratory symptoms were significantly higher in bakers than control croup (pbakers were also significantly greater than control group (pbakers compared to rest period (pbakers than control subjects (pbakers have a higher frequency of work related respiratory symptoms and to a lesser extend allergic symptoms particularly during the work period. PFT values were also significantly reduced among bakers.

  1. Electropolymerized conjugated polyelectrolytes with tunable work function and hydrophobicity as an anode buffer in organic optoelectronics.

    Science.gov (United States)

    Lacher, Sebastian; Obata, Naoki; Luo, Shyh-Chyang; Matsuo, Yutaka; Zhu, Bo; Yu, Hsiao-hua; Nakamura, Eiichi

    2012-07-25

    A new class of conductive polyelectrolyte films with tunable work function and hydrophobicity has been developed for the anode buffer layer in organic electronic devices. The work function of these films featuring a copolymer of ethylenedioxythiophene (EDOT), and its functionalized analogues were found to be easily tunable over a range of almost 1 eV and reach values as high as those of PEDOT:PSS. The new buffer material does not need the addition of any insulating or acidic material that might limit the film conductivity or device lifetime. Organic photovoltaic devices built with these films showed improved open-circuit voltage over those of the known PSS-free conductive EDOT-based polymers with values as high as that obtained for PEDOT:PSS. Furthermore, the surface hydrophobicity of these new copolymer films was found to be sensitive to the chemical groups attached to the polymer backbone, offering an attractive method for surface energy tuning.

  2. Impairment of working memory maintenance and response in schizophrenia: functional magnetic resonance imaging evidence.

    Science.gov (United States)

    Driesen, Naomi R; Leung, Hoi-Chung; Calhoun, Vincent D; Constable, R Todd; Gueorguieva, Ralitza; Hoffman, Ralph; Skudlarski, Pawel; Goldman-Rakic, Patricia S; Krystal, John H

    2008-12-15

    Comparing prefrontal cortical activity during particular phases of working memory in healthy subjects and individuals diagnosed with schizophrenia might help to define the phase-specific deficits in cortical function that contribute to cognitive impairments associated with schizophrenia. This study featured a spatial working memory task, similar to that used in nonhuman primates, that was designed to facilitate separating brain activation into encoding, maintenance, and response phases. Fourteen patients with schizophrenia (4 medication-free) and 12 healthy comparison participants completed functional magnetic resonance imaging while performing a spatial working memory task with two levels of memory load. Task accuracy was similar in patients and healthy participants. However, patients showed reductions in brain activation during maintenance and response phases but not during the encoding phase. The reduced prefrontal activity during the maintenance phase of working memory was attributed to a greater rate of decay of prefrontal activity over time in patients. Cortical deficits in patients did not appear to be related to antipsychotic treatment. In patients and in healthy subjects, the time-dependent reduction in prefrontal activity during working memory maintenance correlated with poorer performance on the memory task. Overall, these data highlight that basic research insights into the distinct neurobiologies of the maintenance and response phases of working memory are of potential importance for understanding the neurobiology of cognitive impairment in schizophrenia and advancing its treatment.

  3. Functional neuroanatomical associations of working memory in early-onset Alzheimer's disease.

    Science.gov (United States)

    Kobylecki, Christopher; Haense, Cathleen; Harris, Jennifer M; Stopford, Cheryl L; Segobin, Shailendra H; Jones, Matthew; Richardson, Anna M T; Gerhard, Alexander; Anton-Rodriguez, José; Thompson, Jennifer C; Herholz, Karl; Snowden, Julie S

    2017-03-16

    To characterize metabolic correlates of working memory impairment in clinically defined subtypes of early-onset Alzheimer's disease. Established models of working memory suggest a key role for frontal lobe function, yet the association in Alzheimer's disease between working memory impairment and visuospatial and language symptoms suggests that temporoparietal neocortical dysfunction may be responsible. Twenty-four patients with predominantly early-onset Alzheimer's disease were clinically classified into groups with predominantly amnestic, multidomain or visual deficits. Patients underwent neuropsychological evaluation focused on the domains of episodic and working memory, T1-weighted magnetic resonance imaging and brain fluorodeoxyglucose positron emission tomography. Fluorodeoxyglucose positron emission tomography data were analysed by using a region-of-interest approach. Patients with multidomain and visual presentations performed more poorly on tests of working memory compared with amnestic Alzheimer's disease. Working memory performance correlated with glucose metabolism in left-sided temporoparietal, but not frontal neocortex. Carriers of the apolipoprotein E4 gene showed poorer episodic memory and better working memory performance compared with noncarriers. Our findings support the hypothesis that working memory changes in early-onset Alzheimer's disease are related to temporoparietal rather than frontal hypometabolism and show dissociation from episodic memory performance. They further support the concept of subtypes of Alzheimer's disease with distinct cognitive profiles due to prominent neocortical dysfunction early in the disease course. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  4. Working memory in multilingual children: is there a bilingual effect?

    Science.gov (United States)

    Engel de Abreu, Pascale M J

    2011-07-01

    This research investigates whether early childhood bilingualism affects working memory performance in 6- to 8-year-olds, followed over a longitudinal period of 3 years. The study tests the hypothesis that bilinguals might exhibit more efficient working memory abilities than monolinguals, potentially via the opportunity a bilingual environment provides to train cognitive control by combating interference and intrusions from the non-target language. A total of 44 bilingual and monolingual children, matched on age, sex, and socioeconomic status, completed assessments of working memory (simple span and complex span tasks), fluid intelligence, and language (vocabulary and syntax). The data showed that the monolinguals performed significantly better on the language measures across the years, whereas no language group effect emerged on the working memory and fluid intelligence tasks after verbal abilities were considered. The study suggests that the need to manage several language systems in the bilingual mind has an impact on children's language skills while having little effects on the development of working memory.

  5. The Effect of Auditory Integration Training on the Working Memory of Adults with Different Learning Preferences

    Science.gov (United States)

    Ryan, Tamara E.

    2014-01-01

    The purpose of this study was to determine the effects of auditory integration training (AIT) on a component of the executive function of working memory; specifically, to determine if learning preferences might have an interaction with AIT to increase the outcome for some learners. The question asked by this quantitative pretest posttest design is…

  6. Working memory in middle-aged males: age related brain activation changes and cognitive fatigue effects

    NARCIS (Netherlands)

    Klaassen, E.B.; Evers, E.A.T.; Groot, R.H.M.; Backes, W.H.; Veltman, D.J.; Jolles, J.

    2014-01-01

    We examined the effects of aging and cognitive fatigue on working memory (WM) related brain activation using functional magnetic resonance imaging. Age-related differences were investigated in 13 young and 16 middle-aged male school teachers. Cognitive fatigue was induced by sustained performance on

  7. A functional MRI study of the influence of practice on component processes of working memory.

    Science.gov (United States)

    Landau, Susan M; Schumacher, Eric H; Garavan, Hugh; Druzgal, T Jason; D'Esposito, Mark

    2004-05-01

    Previous neuroimaging studies have shown that neural activity changes with task practice. The types of changes reported have been inconsistent, however, and the neural mechanisms involved remain unclear. In this study, we investigated the influence of practice on different component processes of working memory (WM) using a face WM task. Event-related functional magnetic resonance imaging (fMRI) methodology allowed us to examine signal changes from early to late in the scanning session within different task stages (i.e., encoding, delay, retrieval), as well as to determine the influence of different levels of WM load on neural activity. We found practice-related decreases in fMRI signal and effects of memory load occurring primarily during encoding. This suggests that practice improves encoding efficiency, especially at higher memory loads. The decreases in fMRI signal we observed were not accompanied by improved behavioral performance; in fact, error rate increased for high WM load trials, indicating that practice-related changes in activation may occur during a scanning session without behavioral evidence of learning. Our results suggest that practice influences particular component processes of WM differently, and that the efficiency of these processes may not be captured by performance measures alone.

  8. The impact of early-onset cannabis use on functional brain correlates of working memory.

    Science.gov (United States)

    Becker, Benjamin; Wagner, Daniel; Gouzoulis-Mayfrank, Euphrosyne; Spuentrup, Elmar; Daumann, Jörg

    2010-08-16

    Cannabis is the most commonly used illicit drug. Prevalence rates are particularly high among adolescents. Neuropsychological studies have identified cannabis-associated memory deficits, particularly linked to an early onset of use. However, it remains unclear, whether the age of onset accounts for altered cortical activation patterns usually observed in cannabis users. Functional magnetic resonance imaging was used to examine cortical activation during verbal working memory challenge in (1) early-onset (onset before the age of sixteen; n=26) and (2) late-onset cannabis users (age at onset at least sixteen; n=17). Early-onset users showed increased activation in the left superior parietal lobe. Correlational analyses confirmed the association between an earlier start of use and increased activity. Contrariwise neither cumulative dose, frequency nor time since last use was significantly associated with cortical activity. Our findings suggest that an early start of cannabis use is associated with increased cortical activation in adult cannabis users, possibly reflecting suboptimal cortical efficiency during cognitive challenge. The maturing brain might be more vulnerable to the harmful effects of cannabis use. However, due to a lack of a non-using control group we cannot exclude alternative interpretations. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  9. Understanding charge transfer of Li+ and Na+ ions scattered from metal surfaces with high work function

    Science.gov (United States)

    Chen, Lin; Wu, Wen-Bin; Liu, Pin-Yang; Xiao, Yun-Qing; Li, Guo-Peng; Liu, Yi-Ran; Jiang, Hao-Yu; Guo, Yan-Ling; Chen, Xi-Meng

    2016-08-01

    For Li+ and Na+ ions scattered from high work function metal surfaces, efficient neutralization is observed, and it cannot be explained by the conventional free electron model. In order to explain these experimental data, we investigate the velocity-dependent neutral fraction with the modified Brako-Newns (BN) model. The calculated results are in agreement with the experimental data. We find that the parallel velocity effect plays an important role in neutralizing the Li+ and Na+ ions for large angle scattering. The nonmonotonic velocity behavior of neutral fraction is strongly related to the distance-dependent coupling strength between the atomic level and metal states. Project supported by the National Natural Science Foundation of China (Grant Nos. 11405078 and 11474140), the Fundamental Research Funds for the Central Universities, China (Grant Nos. lzujbky-2014-169 and lzujbky-2015-244), the Project sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, the State Education Ministry, and the National Students’ Innovation and Entrepreneurship Training Program (Grant Nos. 201410730069 and 201510730078).

  10. Functional activation in the cerebellum during working memory and simple speech tasks.

    Science.gov (United States)

    Durisko, Corrine; Fiez, Julie A

    2010-01-01

    Verbal working memory is the ability to temporarily store and manipulate verbal information. This study tested the predictions of a neuroanatomical model of how the cerebellum contributes to verbal working memory (Desmond et al., 1997). In this model, a large bilateral region in the superior cerebellum is associated with articulatory rehearsal and a right-lateralized region in the inferior cerebellum is associated with the correction of errors within the working memory system. The Desmond et al. (1997) model was based on neuroimaging findings using item recognition tasks and comparisons between working memory and covert rehearsal tasks, whereas in this functional magnetic resonance imaging (fMRI) study we used a delayed serial recall (DSR) task because it relies more heavily on articulatory rehearsal, and our comparison tasks included both overt and covert speech tasks. Our results provide some support for the Desmond et al. (1997) model. In particular, we found multiple activation foci within the superior and inferior sectors of the cerebellum and evidence that these regions show different patterns of activation across working memory and speech tasks. However, the specific patterns of activation were not fully consistent with those reported by Desmond et al. (1997). Namely, our results indicate that activation in the superior sector should be functionally subdivided into a medial focus involved in speech processing and a lateral focus more specific to verbal working memory; the results also indicate that activation in the inferior sector is not uniquely right lateralized. These complex findings speak to the need for future studies to consider the speech-motor aspects of tasks, to investigate the functional significance of adjacent peaks of activation within large regions of cerebellar activation, and to use analysis procedures that support regional distinctions through direct statistical tests. Such studies would help to refine our understanding of how the

  11. Enhancing the Effectiveness of Work Groups and Teams: A Reflection.

    Science.gov (United States)

    Kozlowski, Steve W J

    2017-12-01

    Teamwork has been at the core of human accomplishment across the millennia, and it was a focus of social psychological inquiry on small group behavior for nearly half a century. However, as organizations world-wide reorganized work around teams over the past two decades, the nature of teamwork and factors influencing it became a central focus of research in organizational psychology and management. In this article, I reflect on the impetus, strategy, key features, and scientific contribution of "Enhancing the Effectiveness of Work Groups and Teams," by Kozlowski and Ilgen, a review monograph published in Psychological Science in the Public Interest in 2006.

  12. The Effects of Group Work with Institutionalized Elderly Persons

    Science.gov (United States)

    Duyan, Veli; Sahin-Kara, Gülay; Camur Duyan, Gülsüm; Özdemir, Burcu; Megahead, Hamido A.

    2017-01-01

    Objectives: This research article aims to measure the effects of group therapy on institutionalized elderly in terms of reducing depression and improving psychosocial functioning. Methods: Thirty elderly nursing home residents were recruited, and 16 of them elected to receive group treatment for depression and 14 declined treatment. The…

  13. The Effect of Self-Directed Work Teams on Work Ethic

    Science.gov (United States)

    Lim, Doo Hun; Petty, Gregory; Fontan, Johnny; Yoon, Seung Won

    2008-01-01

    The purpose of this study was to compare work ethic of manufacturing machine operators between a self-directed work team and a traditional work team based on four work ethic subscales and identify differences in work ethic based on six demographic factors. The major findings from the study indicated there were significant differences in the work…

  14. Exposure-in-vivo containing interventions to improve work functioning of workers with anxiety disorder: a systematic review

    Science.gov (United States)

    2010-01-01

    Background Anxiety disorders are associated with functional disability, sickness absence, and decreased productivity. Effective treatments of anxiety disorders can result in remission of symptoms. However the effects on work related outcomes are largely unknown. Exposure in vivo is potentially well fit to improve work-related outcomes. This study systematically reviews the effectiveness of exposure-in-vivo containing interventions in reducing work-related adverse outcomes in workers with anxiety disorders. Methods A systematic study search was conducted in Medline, Cinahl, Embase and Psycinfo. Two reviewers independently extracted data and from each study assessed the quality of evidence by using the GRADE approach. We performed a meta-analysis if data showed sufficient clinical homogeneity. Results Seven studies containing 11 exposure-in-vivo interventions were included. Four studies were focused on Obsessive Compulsive Disorder (OCD), two on Post Traumatic Stress Disorder (PTSD), and one on a mixed group of OCD and severe phobias. The studies were grouped according to type of anxiety disorder and subsequently according to type of comparisons. For OCD, exposure-in-vivo containing interventions can yield better work-related outcomes compared to medication (SSRIs) and relaxation but not better compared to response prevention. The results on anxiety outcomes were similar. The net contribution of exposure in vivo in two OCD intervention programs is also presented as a meta-analysis and shows significant positive results on work role limitations. The calculated pooled effect size with 95% confidence interval was 0.72 (0.28, 1.15). For PTSD, exposure-in-vivo containing interventions can yield better work-related and anxiety-related outcomes compared to a waiting-list but not better compared to imaginal exposure. Conclusions Exposure in vivo as part of an anxiety treatment can reduce work-related adverse outcomes in workers with OCD and PTSD better than various other

  15. Exposure-in-vivo containing interventions to improve work functioning of workers with anxiety disorder: a systematic review

    Directory of Open Access Journals (Sweden)

    Nieuwenhuijsen Karen

    2010-10-01

    Full Text Available Abstract Background Anxiety disorders are associated with functional disability, sickness absence, and decreased productivity. Effective treatments of anxiety disorders can result in remission of symptoms. However the effects on work related outcomes are largely unknown. Exposure in vivo is potentially well fit to improve work-related outcomes. This study systematically reviews the effectiveness of exposure-in-vivo containing interventions in reducing work-related adverse outcomes in workers with anxiety disorders. Methods A systematic study search was conducted in Medline, Cinahl, Embase and Psycinfo. Two reviewers independently extracted data and from each study assessed the quality of evidence by using the GRADE approach. We performed a meta-analysis if data showed sufficient clinical homogeneity. Results Seven studies containing 11 exposure-in-vivo interventions were included. Four studies were focused on Obsessive Compulsive Disorder (OCD, two on Post Traumatic Stress Disorder (PTSD, and one on a mixed group of OCD and severe phobias. The studies were grouped according to type of anxiety disorder and subsequently according to type of comparisons. For OCD, exposure-in-vivo containing interventions can yield better work-related outcomes compared to medication (SSRIs and relaxation but not better compared to response prevention. The results on anxiety outcomes were similar. The net contribution of exposure in vivo in two OCD intervention programs is also presented as a meta-analysis and shows significant positive results on work role limitations. The calculated pooled effect size with 95% confidence interval was 0.72 (0.28, 1.15. For PTSD, exposure-in-vivo containing interventions can yield better work-related and anxiety-related outcomes compared to a waiting-list but not better compared to imaginal exposure. Conclusions Exposure in vivo as part of an anxiety treatment can reduce work-related adverse outcomes in workers with OCD and PTSD

  16. Shift work and quality of sleep: effect of working in designed dynamic light.

    Science.gov (United States)

    Jensen, Hanne Irene; Markvart, Jakob; Holst, René; Thomsen, Tina Damgaard; Larsen, Jette West; Eg, Dorthe Maria; Nielsen, Lisa Seest

    2016-01-01

    To examine the effect of designed dynamic light on staff's quality of sleep with regard to sleep efficiency, level of melatonin in saliva, and subjective perceptions of quality of sleep. An intervention group working in designed dynamic light was compared with a control group working in ordinary institutional light at two comparable intensive care units (ICUs). The study included examining (1) melatonin profiles obtained from saliva samples, (2) quality of sleep in terms of sleep efficiency, number of awakenings and subjective assessment of sleep through the use of sleep monitors and sleep diaries, and (3) subjective perceptions of well-being, health, and sleep quality using a questionnaire. Light conditions were measured at both locations. A total of 113 nurses (88 %) participated. There were no significant differences between the two groups regarding personal characteristics, and no significant differences in total sleep efficiency or melatonin level were found. The intervention group felt more rested (OR 2.03, p = 0.003) and assessed their condition on awakening as better than the control group (OR 2.35, p = 0.001). Intervention-ICU nurses received far more light both during day and evening shifts compared to the control-ICU. The study found no significant differences in monitored sleep efficiency and melatonin level. Nurses from the intervention-ICU subjectively assessed their sleep as more effective than participants from the control-ICU.

  17. An fMRI Investigation of Cerebellar Function During Verbal Working Memory in Methadone Maintenance Patients

    Science.gov (United States)

    Marvel, Cherie L.; Faulkner, Monica L.; Strain, Eric C.; Mintzer, Miriam Z.; Desmond, John E.

    2011-01-01

    Working memory is impaired in opioid-dependent individuals, yet the neural underpinnings of working memory in this population are largely unknown. Previous studies in healthy adults have demonstrated that working memory is supported by a network of brain regions that includes a cerebro-cerebellar circuit. The cerebellum, in particular, may be important for inner speech mechanisms that assist verbal working memory. This study used functional magnetic resonance imaging (fMRI) to examine brain activity associated with working memory in 5 opioid-dependent, methadone-maintained patients and 5 matched, healthy controls. An item recognition task was administered in two conditions: 1) a low working memory load “match” condition in which participants determined whether target letters presented at the beginning of the trial matched a probe item, and 2) a high working memory load “manipulation” condition in which participants counted two alphabetical letters forward of each of the targets and determined whether either of these new items matched a probe item. Response times and accuracy scores were not significantly different between the groups. FMRI analyses indicated that, in association with higher working memory load (“manipulation” condition), the patient group exhibited hyperactivity in the superior and inferior cerebellum and amygdala relative to that of controls. At a more liberal statistical threshold, patients exhibited hypoactivity in the left prefrontal and medial frontal/pre-SMA regions. These results indicate that verbal working memory in opioid-dependent individuals involves a disrupted cerebro-cerebellar circuit, and shed light on the neuroanatomical basis of working memory impairments in this population. PMID:21892700

  18. THE FUNCTIONS OF VIENNESE DIALECT IN THE WORKS OF MODERN AUSTRIAN FICTION

    Directory of Open Access Journals (Sweden)

    Chukshis Vadim Andreevich

    2015-03-01

    Full Text Available The problem of definition of linguistic status of the Austrian dialects and their functions in Austrian fiction continues to preserve the academic value. The main peculiarities of Viennese dialect are given, the conclusions of its status among the other Austrian dialects are made in the article, the characteristic features of the functions of the Viennese dialect are given in the works of Austrian fiction. The author of the article proceeds from the position that the Viennese dialect is the important stylistic means and makes the conclusion about its functions in the works of Austrian fiction. Three novels and one story of modern Austrian writers have been selected for the analysis: H. Anderle (The Worthy Funeral. The Mortal Histories, E. Menasse (Vienna, F. Nabl (Edhof, P Campa (The Second Travel. The article studies four functions of Viennese dialect based on the research of the texts of the Austrian fiction works. The analysis based on the utterances of the heroes helped to prove that Austrian writers use the Viennese dialect as 1 means of marking the regional characteristics; 2 means of marking the age; 3 means of marking the social type and 4 means of emotions expression. The research of the speech of the heroes permitted to reveal the most common Viennese words and expressions and demonstrate their role in the texts not only as the means of creating the speech portrait of the heroes but only the markers of the originality of modern Austrian German.

  19. Functional connectivity in a rat model of Alzheimer's disease during a working memory task.

    Science.gov (United States)

    Liu, Tiaotiao; Bai, Wenwen; Yi, Hu; Tan, Tao; Wei, Jing; Wang, Ju; Tian, Xin

    2014-01-01

    Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive loss of memory. Impairment of working memory was typically observed in AD. The concept of brain functional connectivity plays an important role in neuroscience as a useful tool to understand the organized behavior of brain. Hence, the purpose of this study is to investigate the possible mechanism of working memory deficits in AD from a new perspective of functional connectivity. Rats were randomly divided into 2 groups: Aβ injection group (Aβ₁₋₄₂-induced toxicity rat model) and control group. Multi-channel local field potentials (LFPs) were obtained from rat prefrontal cortex with implanted microelectrode arrays while the rats performed a Y-maze working memory task. The short-time Fourier transform was utilized to analyze the power changes in LFPs and sub-bands (in particular theta and low gamma bands) were extracted via band filtering. Then the Directed transfer function (DTF) method was applied to calculate the functional connections among LFPs. From the DTF calculation, the causal networks in the sub-bands were identified. DTFmean (mean of connectivity matrix elements) was used to quantify connection strength as well as global efficiency (Eglob) was calculated to quantitatively describe the efficient of information transfer in the network. Our results showed that both connection strength and efficient of information transfer increased during the working memory task in the control group; by contrast, there was no significantly change in the Aβ injection group. These findings could lead to improve the understanding of the mechanism of working memory deficits in AD.

  20. Facile Doping and Work-Function Modification of Few-Layer Graphene Using Molecular Oxidants and Reductants

    KAUST Repository

    Mansour, Ahmed

    2017-01-03

    Doping of graphene is a viable route toward enhancing its electrical conductivity and modulating its work function for a wide range of technological applications. In this work, the authors demonstrate facile, solution-based, noncovalent surface doping of few-layer graphene (FLG) using a series of molecular metal-organic and organic species of varying n- and p-type doping strengths. In doing so, the authors tune the electronic, optical, and transport properties of FLG. The authors modulate the work function of graphene over a range of 2.4 eV (from 2.9 to 5.3 eV)-unprecedented for solution-based doping-via surface electron transfer. A substantial improvement of the conductivity of FLG is attributed to increasing carrier density, slightly offset by a minor reduction of mobility via Coulomb scattering. The mobility of single layer graphene has been reported to decrease significantly more via similar surface doping than FLG, which has the ability to screen buried layers. The dopant dosage influences the properties of FLG and reveals an optimal window of dopant coverage for the best transport properties, wherein dopant molecules aggregate into small and isolated clusters on the surface of FLG. This study shows how soluble molecular dopants can easily and effectively tune the work function and improve the optoelectronic properties of graphene.

  1. Reaction Times to Consecutive Automation Failures: A Function of Working Memory and Sustained Attention.

    Science.gov (United States)

    Jipp, Meike

    2016-12-01

    This study explored whether working memory and sustained attention influence cognitive lock-up, which is a delay in the response to consecutive automation failures. Previous research has demonstrated that the information that automation provides about failures and the time pressure that is associated with a task influence cognitive lock-up. Previous research has also demonstrated considerable variability in cognitive lock-up between participants. This is why individual differences might influence cognitive lock-up. The present study tested whether working memory-including flexibility in executive functioning-and sustained attention might be crucial in this regard. Eighty-five participants were asked to monitor automated aircraft functions. The experimental manipulation consisted of whether or not an initial automation failure was followed by a consecutive failure. Reaction times to the failures were recorded. Participants' working-memory and sustained-attention abilities were assessed with standardized tests. As expected, participants' reactions to consecutive failures were slower than their reactions to initial failures. In addition, working-memory and sustained-attention abilities enhanced the speed with which participants reacted to failures, more so with regard to consecutive than to initial failures. The findings highlight that operators with better working memory and sustained attention have small advantages when initial failures occur, but their advantages increase across consecutive failures. The results stress the need to consider personnel selection strategies to mitigate cognitive lock-up in general and training procedures to enhance the performance of low ability operators. © 2016, Human Factors and Ergonomics Society.

  2. Reorganization of functional brain networks mediates the improvement of cognitive performance following real-time neurofeedback training of working memory.

    Science.gov (United States)

    Zhang, Gaoyan; Yao, Li; Shen, Jiahui; Yang, Yihong; Zhao, Xiaojie

    2015-05-01

    Working memory (WM) is essential for individuals' cognitive functions. Neuroimaging studies indicated that WM fundamentally relied on a frontoparietal working memory network (WMN) and a cinguloparietal default mode network (DMN). Behavioral training studies demonstrated that the two networks can be modulated by WM training. Different from the behavioral training, our recent study used a real-time functional MRI (rtfMRI)-based neurofeedback method to conduct WM training, demonstrating that WM performance can be significantly improved after successfully upregulating the activity of the target region of interest (ROI) in the left dorsolateral prefrontal cortex (Zhang et al., [2013]: PloS One 8:e73735); however, the neural substrate of rtfMRI-based WM training remains unclear. In this work, we assessed the intranetwork and internetwork connectivity changes of WMN and DMN during the training, and their correlations with the change of brain activity in the target ROI as well as with the improvement of post-training behavior. Our analysis revealed an "ROI-network-behavior" correlation relationship underlying the rtfMRI training. Further mediation analysis indicated that the reorganization of functional brain networks mediated the effect of self-regulation of the target brain activity on the improvement of cognitive performance following the neurofeedback training. The results of this study enhance our understanding of the neural basis of real-time neurofeedback and suggest a new direction to improve WM performance by regulating the functional connectivity in the WM related networks. © 2014 Wiley Periodicals, Inc.

  3. Factors influencing work functioning after cancer diagnosis: a focus group study with cancer survivors and occupational health professionals

    OpenAIRE

    Dorland, H. F.; Abma, F. I.; Roelen, C. A. M.; Smink, J. G.; Ranchor, A V; Bultmann, U.

    2015-01-01

    Purpose Cancer survivors (CSs) frequently return to work, but little is known about work functioning after return to work (RTW). We aimed to identify barriers and facilitators of work functioning among CSs. Methods Three focus groups were conducted with CSs (n?=?6, n?=?8 and n?=?8) and one focus group with occupational health professionals (n?=?7). Concepts were identified by thematic analysis, using the Cancer and Work model as theoretical framework to structure the results. Results Long-las...

  4. Combined effect of back pain and stress on work ability.

    Science.gov (United States)

    Oberlinner, C; Yong, M; Nasterlack, M; Pluto, R-P; Lang, S

    2015-03-01

    Back pain and occupational stress are known risk factors for absenteeism and presenteeism. In addition, the relationship between back pain (BP) and psychosocial stressors has been examined in numerous studies. To examine the prevalence of BP and perceived stress among employees of different occupational status and to investigate their combined impact on work ability. A comprehensive survey combining questionnaire data and medical examination offered in one division of a major chemical company in Germany. Self-rated health and work ability were assessed using the Work Ability Index (WAI). A synergy index was used to assess a potential interaction between both exposures under an additive model. Of 867 voluntary participants, 653 returned complete questionnaires on BP and job stress perception. Although occupational stressors were perceived differently, there was no difference in the prevalence of BP between the occupational groups. Back pain and stress perception are correlated with each other and both are negatively associated with work ability. After adjustment for occupational status, demographic and lifestyle factors, we found a synergy effect of BP and stress perception with a modest to strong impact on declining WAI. Corporate health promotion interventions to reduce the impact of BP and stress perception on work ability should target both physical and psychological dimensions. Such interventions may be initiated in the context of regular (occupational) medical examinations. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Effectiveness of Student Learning during Experimental Work in Primary School.

    Science.gov (United States)

    Logar, Ana; Peklaj, Cirila; Ferk Savec, Vesna

    2017-09-01

    The aim of the research was to optimize the effectiveness of student learning based on experimental work in chemistry classes in Slovenian primary schools. To obtain evidence about how experimental work is implemented during regular chemistry classes, experimental work was videotaped during 19 units of chemistry lessons at 12 Slovenian primary schools from the pool of randomly selected schools. Altogether 332 eight-grade students were involved in the investigation, with an average age of 14.2 years. Students were videotaped during chemistry lessons, and their worksheets were collected afterward. The 12 chemistry teachers, who conducted lessons in these schools, were interviewed before the lessons; their teaching plans were also collected. The collected data was analyzed using qualitative methods. The results indicate that many teachers in Slovenian primary schools are not fully aware of the potential of experimental work integrated into chemistry lessons for the development of students' experimental competence. Further research of the value of different kinds of training to support teachers for the use of experimental work in chemistry teaching is needed.

  6. WORK FUNCTION CHARACTERIZATION OF DIRECTIONALLY SOLIDIFIED LAB6VB2 EUTECTIC (POSTPRINT)

    Science.gov (United States)

    2017-05-10

    Ultramicroscopy 0 0 0 (2017) 1–5 Contents lists available at ScienceDirect Ultramicroscopy journal homepage: www.elsevier.com/locate/ultramic Work function...temperature to the primarily the B 2 at 977 °C. Although the SPLEEM is capable of heating the samples to tem - eratures that are typical of a working...by e -beam nd thermal evaporation during image acquisition at room tem - erature. Fig. 5 (a), (b), (c) shows the results of the dosing exper- ments

  7. Development of utility generic functional requirements for electronic work packages and computer-based procedures

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-06-01

    The Nuclear Electronic Work Packages - Enterprise Requirements (NEWPER) initiative is a step toward a vision of implementing an eWP framework that includes many types of eWPs. This will enable immediate paper-related cost savings in work management and provide a path to future labor efficiency gains through enhanced integration and process improvement in support of the Nuclear Promise (Nuclear Energy Institute 2016). The NEWPER initiative was organized by the Nuclear Information Technology Strategic Leadership (NITSL) group, which is an organization that brings together leaders from the nuclear utility industry and regulatory agencies to address issues involved with information technology used in nuclear-power utilities. NITSL strives to maintain awareness of industry information technology-related initiatives and events and communicates those events to its membership. NITSL and LWRS Program researchers have been coordinating activities, including joint organization of NEWPER-related meetings and report development. The main goal of the NEWPER initiative was to develop a set of utility generic functional requirements for eWP systems. This set of requirements will support each utility in their process of identifying plant-specific functional and non-functional requirements. The NEWPER initiative has 140 members where the largest group of members consists of 19 commercial U.S. nuclear utilities and eleven of the most prominent vendors of eWP solutions. Through the NEWPER initiative two sets of functional requirements were developed; functional requirements for electronic work packages and functional requirements for computer-based procedures. This paper will describe the development process as well as a summary of the requirements.

  8. The Effectiveness of Marriage Enrichment Training on Job Stress and Quality of Work Life of working women

    National Research Council Canada - National Science Library

    H; Z salak

    2016-01-01

    .... Because more women than men experience job stress, the purpose of this study was to investigate the effectiveness of marriage enrichment training on job stress and quality of work life of working...

  9. The Effect of Working Memory Training on English Reading Comprehension of Adult English Learners

    Directory of Open Access Journals (Sweden)

    Gholam Reza Kiany

    2016-12-01

    Full Text Available Introduction: It is assumed that working memory plays a pivotal role in carrying out all sorts of cognitive functions. The introduction of working memory software has provided researchers with an asset to investigate the differences among individuals which can be attributable to differences in working memory capacity. Following the advent of working memory software, there were also other pieces of software available to the public with the prospect of helping individuals enhance their working memory capacity and as a result enjoy any possible benefits. This study aimed at investigating the possible effects of working memory improvement on some university students’ reading comprehension in English. Methods: 30 adult university students chosen through convenience sampling approach participated in this study. They were randomly divided into an experimental and a control group. Both groups took pretest on their reading comprehension using three reading texts in English and working memory capacity carried out via the working memory software. While the control group took posttests on the same tests after five weeks, the experimental group underwent a working memory training program consisting of ten sessions before taking the posttests. Results: The results of t-test analysis showed a significant statistical difference in the performance of the two groups on the working memory test, but their reading task performance scores did not show a significant difference. Conclusion: The working memory training program did not seem to benefit the participants in carrying out reading comprehension in English.

  10. Information Updating in Working Memory: Its Effect on Teacher Efficacy

    Directory of Open Access Journals (Sweden)

    Jun Tao

    2012-01-01

    Full Text Available Teacher efficacy has a great impact on effective teaching and has been studied in various perspectives. The updating information ability in working memory is always related with many capabilities of cognition. An experiment of N-back task and a questionnaire of teacher efficacy were conducted in this study to test the effect of the ability of information updating in working memory on the teacher efficacy. A significant difference was found in the reaction time between high teacher efficacy group and low teacher efficacy group. The results showed that teachers who scored higher in the teacher efficacy scale tended to react faster than those who scored lower based on the same accuracy. And the updating information ability could serve as a predictor of teacher efficacy.

  11. Effects of strategy on visual working memory capacity.

    Science.gov (United States)

    Bengson, Jesse J; Luck, Steven J

    2016-02-01

    Substantial evidence suggests that individual differences in estimates of working memory capacity reflect differences in how effectively people use their intrinsic storage capacity. This suggests that estimated capacity could be increased by instructions that encourage more effective encoding strategies. The present study tested this by giving different participants explicit strategy instructions in a change detection task. Compared to a condition in which participants were simply told to do their best, we found that estimated capacity was increased for participants who were instructed to remember the entire visual display, even at set sizes beyond their capacity. However, no increase in estimated capacity was found for a group that was told to focus on a subset of the items in supracapacity arrays. This finding confirms the hypothesis that encoding strategies may influence visual working memory performance, and it is contrary to the hypothesis that the optimal strategy is to filter out any items beyond the storage capacity.

  12. The perverse effects of competition on scientists' work and relationships.

    Science.gov (United States)

    Anderson, Melissa S; Ronning, Emily A; De Vries, Raymond; Martinson, Brian C

    2007-12-01

    Competition among scientists for funding, positions and prestige, among other things, is often seen as a salutary driving force in U.S. science. Its effects on scientists, their work and their relationships are seldom considered. Focus-group discussions with 51 mid- and early-career scientists, on which this study is based, reveal a dark side of competition in science. According to these scientists, competition contributes to strategic game-playing in science, a decline in free and open sharing of information and methods, sabotage of others' ability to use one's work, interference with peer-review processes, deformation of relationships, and careless or questionable research conduct. When competition is pervasive, such effects may jeopardize the progress, efficiency and integrity of science.

  13. Efficacy of Training of Executive Functions (Working Memory on the Rate of Attention in Preschool Children with Developmental Coordination Disorder

    Directory of Open Access Journals (Sweden)

    Farnoush Kavianpour

    2014-09-01

    Full Text Available Background: The present study aims to investigate the efficacy of executive functions training (working memory on the rate of attention in preschool children with developmental coordination disorder in Isfahan city. Materials and Methods: The participants of this study were three preschool children which were recognized to have developmental coordination disorder. To collect data used NEPSY neuropsychology test, Conner’s parent rating scale, Wechsler intelligence scale for children, basic motor ability tests and clinical interview. Results: The results of the data chart analysis based on descriptive statistics' and visual analysis indices revealed that the intervention has been effective on the three participants [respectively PND (Percentage of Non-Overlapping Data 80, 70 and 50% for test number one, two and three]. Conclusion: The results of the present study show that working memory executive function training, the rate of attention deficit can be reduced.

  14. `Sex' – It's not only Women's Work: A Case for Refocusing on the Functional Role that Sex Plays in Work for both Women and Men

    OpenAIRE

    URETSKY, ELANAH

    2014-01-01

    Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `...

  15. The Effects of Two Types of Sleep Deprivation on Visual Working Memory Capacity and Filtering Efficiency

    OpenAIRE

    Drummond, Sean P.A.; Dane E Anderson; Straus, Laura D.; Vogel, Edward K.; Perez, Veronica B.

    2012-01-01

    Sleep deprivation has adverse consequences for a variety of cognitive functions. The exact effects of sleep deprivation, though, are dependent upon the cognitive process examined. Within working memory, for example, some component processes are more vulnerable to sleep deprivation than others. Additionally, the differential impacts on cognition of different types of sleep deprivation have not been well studied. The aim of this study was to examine the effects of one night of total sleep depri...

  16. The control of independent students’ work effectiveness during pathophysiology study

    Directory of Open Access Journals (Sweden)

    О. V. Melnikova

    2013-06-01

    Full Text Available The course of Pathophysiology study includes both auditoria hours (lectures and practical classes and independent work of students. The latter makes up 38% of total hours given for Pathophysiology study. Independent work of students includes the following items: preparation for practical classes, writing reviews on different topics, preparation for current and final computer testing, study of the topics which are not discussed during lectures and practical classes. In order to assimilate the course of Pathophysiology completely students should effectively use their hours given for independent work. Unfortunately, the level of students’ independent individual work is low; it includes only learning of single facts, that is not enough for higher medical education. THE AIM OF STUDY: To propose the method of control of the effectiveness of students’ independent work. The most important part of student’s individual work is preparation for study in auditoria, because it determines the qualitative level of study during practical classes. The student should enter the class not only with the knowledge of basic sciences (Anatomy, Histology, Biochemistry, Normal Physiology etc. but also with the understanding of key items of the topic of the practical class. The problem consists in the following: the teacher can’t check the level of basic knowledge in each student – there is not enough time during practical class for this procedure. In order to increase the effectiveness of individual students’ work a special workbook for the practical classes was developed at the Pathophysiology department. While preparing for practical classes students write down basic items of the topic, refresh some questions from Normal Physiology, Biochemistry and other subjects. In the beginning of the practical class the teacher controls the level of student’s preparation to the topic by checking the fulfillment of tasks in the workbook. It takes a little time, but it

  17. Oscillatory lower body negative pressure impairs working memory task-related functional hyperemia in healthy volunteers.

    Science.gov (United States)

    Merchant, Sana; Medow, Marvin S; Visintainer, Paul; Terilli, Courtney; Stewart, Julian M

    2017-04-01

    Neurovascular coupling (NVC) describes the link between an increase in task-related neural activity and increased cerebral blood flow denoted "functional hyperemia." We previously showed induced cerebral blood flow oscillations suppressed functional hyperemia; conversely functional hyperemia also suppressed cerebral blood flow oscillations. We used lower body negative pressure (OLBNP) oscillations to force oscillations in middle cerebral artery cerebral blood flow velocity (CBFv). Here, we used N-back testing, an intellectual memory challenge as a neural activation task, to test the hypothesis that OLBNP-induced oscillatory cerebral blood flow can reduce functional hyperemia and NVC produced by a working memory task and can interfere with working memory. We used OLBNP (-30 mmHg) at 0.03, 0.05, and 0.10 Hz and measured spectral power of CBFv at all frequencies. Neither OLBNP nor N-back, alone or combined, affected hemodynamic parameters. 2-Back power and OLBNP individually were compared with 2-back power during OLBNP. 2-Back alone produced a narrow band increase in oscillatory arterial pressure (OAP) and oscillatory cerebral blood flow power centered at 0.0083 Hz. Functional hyperemia in response to 2-back was reduced to near baseline and 2-back memory performance was decreased by 0.03-, 0.05-, and 0.10-Hz OLBNP. OLBNP alone produced increased oscillatory power at frequencies of oscillation not suppressed by added 2-back. However, 2-back preceding OLBNP suppressed OLBNP power. OLBNP-driven oscillatory CBFv blunts NVC and memory performance, while memory task reciprocally interfered with forced CBFv oscillations. This shows that induced cerebral blood flow oscillations suppress functional hyperemia and functional hyperemia suppresses cerebral blood flow oscillations.NEW & NOTEWORTHY We show that induced cerebral blood flow oscillations suppress functional hyperemia produced by a working memory task as well as memory task performance. We conclude that oscillatory

  18. Visual Working Memory Load-Related Changes in Neural Activity and Functional Connectivity

    OpenAIRE

    Ling Li; Jin-Xiang Zhang; Tao Jiang

    2011-01-01

    BACKGROUND: Visual working memory (VWM) helps us store visual information to prepare for subsequent behavior. The neuronal mechanisms for sustaining coherent visual information and the mechanisms for limited VWM capacity have remained uncharacterized. Although numerous studies have utilized behavioral accuracy, neural activity, and connectivity to explore the mechanism of VWM retention, little is known about the load-related changes in functional connectivity for hemi-field VWM retention. MET...

  19. Electron injection into organic semiconductor devices from high work function cathodes

    OpenAIRE

    Hoven, Corey V.; Yang, Renqiang; Garcia, Andres; Crockett, Victoria; Heeger, Alan J.; Bazan, Guillermo C.; Nguyen, Thuc-Quyen

    2008-01-01

    We show that polymer light-emitting diodes with high work-function cathodes and conjugated polyelectrolyte injection/transport layers exhibit excellent efficiencies despite large electron-injection barriers. Correlation of device response times with structure provides evidence that the electron-injection mechanism involves redistribution of the ions within the polyelectrolyte electron-transport layer and hole accumulation at the interface between the emissive and electron-transport layers. Bo...

  20. Work function tuning for high-performance solution-processed organic photodetectors with inverted structure.

    Science.gov (United States)

    Saracco, Emeline; Bouthinon, Benjamin; Verilhac, Jean-Marie; Celle, Caroline; Chevalier, Nicolas; Mariolle, Denis; Dhez, Olivier; Simonato, Jean-Pierre

    2013-12-03

    Organic photodetectors with inverted structure are fabricated by solution process techniques. A very thin interfacing layer of polyethyleneimine leads to a homogenous interface with low work function. The devices exhibit excellent performances, in particular in terms of low dark current density, wide range linearity, high detectivity, and remarkable stability in ambient air without encapsulation. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Working memory, attention, and executive function in Alzheimer's disease and frontotemporal dementia.

    Science.gov (United States)

    Stopford, Cheryl L; Thompson, Jennifer C; Neary, David; Richardson, Anna M T; Snowden, Julie S

    2012-04-01

    Working memory deficits are a recognised feature of Alzheimer's disease (AD). They are commonly ascribed to central executive impairment and assumed to relate to frontal lobe dysfunction. Performance failures on standard tests of attention and executive function reinforce this interpretation. Nevertheless, early-onset AD patients do not show the frank behavioural changes indicative of frontal lobe dysfunction, and the characteristic functional neuroimaging changes are in posterior hemispheres rather than frontal lobes. We explored this anomaly through a comparison of working memory, attention and executive test performance in patients with AD (a 'typical' early-onset group with deficits in memory, language and perceptuospatial function and an 'amnesic' group) and frontotemporal dementia (FTD). Typical-AD and FTD patients both showed impaired performance, whereas amnesic-AD patients performed well. Despite similar quantitative performance measures, typical-AD and FTD patients showed qualitatively distinct performance profiles. Impairments in FTD patients were interpreted in 'frontal' executive terms as deficits in attention, set shifting and response inhibition. AD patients' performance appeared to be influenced by information load and was interpreted in terms of working memory capacity. In keeping with these different interpretations, neuroimaging showed characteristic frontal lobe abnormalities in FTD and temporoparietal change in typical-AD. The findings highlight the importance of the posterior hemispheres in working memory and point to a need for caution in the automatic attribution of working memory, attention and executive test failures to frontal lobe failure. They underline also the phenotypic variation within AD. Copyright © 2010 Elsevier Srl. All rights reserved.

  2. Effect of specimen size on work-of-fracture measurements.

    Science.gov (United States)

    Rogers, L L; Moyle, D D

    1988-01-01

    It has been suggested that work-of-fracture, which quantifies the ability of a material to resist fracture, is dependent on specimen size. This experiment compared work-of-fracture, calculated as energy per unit area, for different specimen sizes of Plexiglas, bovine tibial bone and aluminum. Three different geometrically similar cross sections were tested for each material for a total of 54 specimens. Work-of-fracture was measured by loading a notched beam (triangular cross section) in three-point bending at a constant deformation rate. The energy necessary to cause fracture was measured from a load-deformation curve. Specimen fracture area was determined using macrophotography. Atomic absorption spectrophotometry was used to determine weight percent calcium of bone specimens and quantitative light microscopy was used to determine fractional void area. Analysis of variance showed no effect of specimen size on work-of-fracture for aluminum or Plexiglas specimens (p greater than 0.05). A significant difference was found, however, between the large (area = 11.7 +/- 1.9 mm2) and small (area = 3.48 +/- 0.68 mm2) bone specimens and between the medium (area = 5.89 +/- 0.69 mm2) and small (area = 3.48 +/- 0.68 mm2) bone specimens. No correlation was found between work-of-fracture and either calcium content (r2 = 0.128) or fractional void area (r2 = 0.0713). The mean work-of-fracture values found are as follows: aluminum, 59.8 +/- 13.7 kJ m-2; Plexiglas, 0.620 +/- 0.074 kJ m-2; bone (area 5.89 +/- 0.69 mm2-11.7 +/- 1.9 mm2), 9.72 +/- 1.93 kJ m-2 and bone (area 3.48 +/- 0.68 mm2), 5.48 +/- 1.79 kJ m-2.

  3. Exposure to Blue Light Increases Subsequent Functional Activation of the Prefrontal Cortex During Performance of a Working Memory Task.

    Science.gov (United States)

    Alkozei, Anna; Smith, Ryan; Pisner, Derek A; Vanuk, John R; Berryhill, Sarah M; Fridman, Andrew; Shane, Bradley R; Knight, Sara A; Killgore, William D S

    2016-09-01

    Prolonged exposure to blue wavelength light has been shown to have an alerting effect, and enhances performance on cognitive tasks. A small number of studies have also shown that relatively short exposure to blue light leads to changes in functional brain responses during the period of exposure. The extent to which blue light continues to affect brain functioning during a cognitively challenging task after cessation of longer periods of exposure (i.e., roughly 30 minutes or longer), however, has not been fully investigated. A total of 35 healthy participants (18 female) were exposed to either blue (469 nm) (n = 17) or amber (578 nm) (n = 18) wavelength light for 30 minutes in a darkened room, followed immediately by functional magnetic resonance imaging (fMRI) while undergoing a working memory task (N-back task). Participants in the blue light condition were faster in their responses on the N-back task and showed increased activation in the dorsolateral (DLPFC) and ventrolateral (VLPFC) prefrontal cortex compared to those in the amber control light condition. Furthermore, greater activation within the VLPFC was correlated with faster N-back response times. This is the first study to suggest that a relatively brief, single exposure to blue light has a subsequent beneficial effect on working memory performance, even after cessation of exposure, and leads to temporarily persisting functional brain changes within prefrontal brain regions associated with executive functions. These findings may have broader implication for using blue-enriched light in a variety of work settings where alertness and quick decision-making are important. © 2016 Associated Professional Sleep Societies, LLC.

  4. Effects of Childhood Gymnastics Program on Spatial Working Memory.

    Science.gov (United States)

    Hsieh, Shu-Shih; Lin, Chih-Chien; Chang, Yu-Kai; Huang, Chun-Ju; Hung, Tsung-Min

    2017-08-07

    A growing body of evidence has demonstrated the positive effects of physical exercise on cognition in children, and recent studies have specifically investigated the cognitive benefits of exercises involving cognitive-motor interactions, such as gymnastics. This study examined the effect of 8 weeks of gymnastics training on behavioral and neurophysiological measures of spatial working memory in children. Forty-four children aged 7 to 10 yrs were recruited. The experimental group (n = 24; age: 8.7 ± 1.1 yrs) were recruited from Yilan County in Taiwan, while the control group (n = 20; age: 8.6 ± 1.1 yrs) resided in Taipei City. The experimental group undertook 8 weeks of after-school gymnastics training (2 sessions/week, 90 minutes/session), while the control group received no intervention, and were instructed to maintain their routine daily activities. Working memory was assessed by performance on a modified delayed match-to-sample test, and by event-related potential including the P3 component. Data was collected pre and post treatment for the experimental group, and at the same time interval for the control group. Response accuracy improved following the experimental intervention regardless of working memory demands. Likewise, the P3 amplitude was larger at the parietal site after gymnastics training regardless of the task difficulty. Our results suggest that a short period of gymnastics training had a general facilitative effect on spatial working memory at both a behavioral and neurophysiological level in children. These finding highlight the potential importance of exercise programs involving cognitive-motor interactions in stimulating development of spatial cognition during childhood.

  5. The effect of working alliance on adherence and outcome in cognitive remediation therapy.

    Science.gov (United States)

    Huddy, Vyv; Reeder, Clare; Kontis, Dimitris; Wykes, Til; Stahl, Daniel

    2012-07-01

    Cognitive remediation therapy (CRT) for schizophrenia has been effective in improving cognitive and global functioning outcomes. It is now important to determine what factors maximize benefit. The quality of relationship--or working alliance--between clients and therapists may be one such factor that improves outcome. To investigate this, 49 individuals with schizophrenia were recruited into a naturalistic study of the impact of CRT on work and structured activity outcomes. Participant's cognitive skills, severity of symptoms, and social skills were assessed at baseline. Both client and therapist working alliance ratings were gathered early in therapy. After controlling for depression, clients who rated the alliance more favorably stayed in therapy longer and were more likely to improve on their main target complaint but notably not on working memory performance or self-esteem. Therapist's ratings of the alliance were not associated with memory outcome. These findings indicate that working alliance is important for client satisfaction with therapy.

  6. Impaired executive functioning in subclinical compulsive checking with ecologically valid stimuli in a Working Memory task

    Directory of Open Access Journals (Sweden)

    Ben eHarkin

    2011-05-01

    Full Text Available We previously showed that working memory performance of subclinical checkers can be affected if they are presented with irrelevant but misleading information during the retention period (Harkin & Kessler, 2009, 2010. The present study differed from our previous research in the three crucial aspects. Firstly, we employed ecologically valid stimuli in form of electrical kitchen appliances on a kitchen countertop in order to address previous criticism of our stimuli in terms of validity with respect to compulsive checking symptomatology. Secondly, we tested whether the new stimuli would allow us to employ a simpler (un-blocked design while obtaining similarly robust results. Thirdly, in Experiment 2 we improved the measure of confidence as a metacognitive variable by using a quantitative scale (0-100, which indeed revealed more robust effects that were quantitatively related to accuracy of performance. The task in the present study was to memorise four appliances, incl. their states (on/off, and their locations on the kitchen countertop. Memory accuracy was tested for the states of appliances in Experiment 1, and for their locations in Experiment 2. Intermediate probes were identical in both Experiments and were administered during retention on 2/3 of the trials with 50% resolvable and 50% misleading probes. Experiment 1 revealed a general impairment of high checkers, which confirmed the efficacy of our stimuli. In Experiment 2 we observed the expected, more differentiated pattern: High checkers were not generally affected in their WM performance (i.e., no general capacity issue; instead they showed a particular impairment in the misleading distractor-probe condition. Also, high checkers’ confidence ratings were indicative of a general impairment in metacognitive functioning.

  7. Evidence for the effect of depth on visual working memory.

    Science.gov (United States)

    Qian, Jiehui; Li, Jiaofeng; Wang, Kaiyue; Liu, Shengxi; Lei, Quan

    2017-07-25

    Visual working memory (VWM) is a cognitive memory buffer for temporarily holding, processing, and manipulating visual information. Previous studies have demonstrated mixed results of the effect of depth perception on VWM, with some showing a beneficial effect while others not. In this study, we employed an adapted change detection paradigm to investigate the effects of two depth cues, binocular disparity and relative size. The memory array consisted of a set of pseudo-randomly positioned colored items, and the task was to judge whether the test item was changed compared to the memory item after a retention interval. We found that presenting the items in stereoscopic depth alone hardly affected VWM performance. When combining the two coherent depth cues, a significant larger VWM capacity of the perceptually closer-in-depth items was observed than that of the farther items, but the capacity for the two-depth-planes condition was not significantly different from that for the one-plane condition. Conflicting the two depth cues resulted in cancelling the beneficial effect of presenting items at a closer depth plane. The results indicate that depth perception could affect VWM, and the visual system may have an advantage in maintaining closer-in-depth objects in working memory.

  8. [Functional digestive disorders in infants. Working protocol of diagnostic and treatment].

    Science.gov (United States)

    Khavkin, A I; Bel'mer, S V; Zakharova, I N; Keshishian, E S; Pampura, A N; Faĭzullina, R A

    2014-01-01

    Functional digestive disorders in infants comprise a group of disorders characterized by several specific features. They are related to structural and physiological peculiarities of the gastrointestinal tract in children during lactotrophic period of nutrition, limited pharmacotherapeutic options and supremacy of dietary correction in this age group, and psychological discomfort that has a negative impact on the quality of life of the whole family. The working protocol "Functional gastrointestinal disorders in infants' was prepared by the Russian Society for Pediatric Gastroenterology, Hepatology, and Nutrition (RusPGHAN) based on the previously proposed European (ESPGHAN) and American (NASPGHAN) guidelines. The protocol includes detailed description of the current approaches to diagnosis and management of the functional digestive disorders in young children, as well as algorithm tables that can be used by pediatricians and familial physicians in routine clinical practice.

  9. Effects of antidepressant drugs on sexual function.

    Science.gov (United States)

    Baldwin, D S; Thomas, S C; Birtwistle, J

    1997-01-01

    Adequate sexual expression is an essential part of human relationships, enhancing quality of life and providing a sense of physical, psychological and social well-being. Unfortunately, depression is associated with impairments of sexual function and satisfaction. These problems can worsen a quality of life that is already reduced by the effects of depressive illness. The existing antidepressant drugs are far from ideal, most having adverse effects on sexual function. Unfortunately, the exact incidence of sexual dysfunction during treatment with many antidepressants is not known. Disturbances of sexual interest and performance will only be detected in a reliable fashion when systematic enquiries are made during the course of the standard clinical interview. Growing awareness of the adverse effects of many antidepressants on sexual function has led to some re-evaluation of the earlier claims for the good tolerability of many of the newer drugs. There is a clear need for further well-designed controlled studies of the effects of antidepressants on sexual function, so that this aspect of the tolerability of differing drugs can be assessed more reliably. (IntJ Psych Clin Pract 1997; 1: 47-58).

  10. Propofol Induction's Effect on Cardiac Function

    Science.gov (United States)

    2015-03-31

    This Study Was Focused to Evaluate Feasibility of Doppler Tissue Monitoring During the Induction Anesthesia,; and Evaluate Routine Propofol Induction's Effect on Myocardial Tissue Motion, Using Non-invasive Doppler Tissue and 2D Speckle Tracking Imaging.; This is the First Study, to Our Knowledge, Which Has Evaluated the Possible Impact of Propofol Induction on LV Function.

  11. Effects of posture on postoperative pulmonary function

    DEFF Research Database (Denmark)

    Nielsen, K G; Holte, Kathrine; Kehlet, H

    2003-01-01

    BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed...

  12. Strategic Games and Truly Playable Effectivity Functions

    DEFF Research Database (Denmark)

    Goranko, Valentin; Jamroga, Wojtek; Turrini, Paolo

    2011-01-01

    A well known (and often used) result by Marc Pauly states that for every playable effectivity function E there exists a strategic game that assigns to coalitions exactly the same power as E, and vice versa. While the latter direction of the correspondence is correct, we show that the former does ...

  13. Health and psychosocial effects of flexible working hours

    Directory of Open Access Journals (Sweden)

    Daniela Janssen

    2004-12-01

    Full Text Available OBJECTIVE: To examine whether any impairments in health and social lives can be found under different kinds of flexible working hours, and whether such effects are related to specific characteristics of these working hours. METHODS: Two studies - a company based survey (N=660 and an internet survey (N=528 - have been conducted. The first one was a questionnaire study (paper and pencil on employees working under some 'typical' kinds of different flexible working time arrangements in different companies and different occupational fields (health care, manufacturing, retail, administration, call centres. The second study was an internet-based survey, using an adaptation of the questionnaire from the first study. RESULTS: The results of both studies consistently show that high variability of working hours is associated with increased impairments in health and well-being and this is especially true if this variability is company controlled. These effects are less pronounced if variability is self-controlled; however, autonomy does not compensate the effects of variability. CONCLUSIONS: Recommendations for an appropriate design of flexible working hours should be developed in order to minimize any impairing effects on health and psychosocial well-being; these recommendations should include - besides allowing for discretion in controlling one's (flexible working hours - that variability in flexible working hours should be kept low (or at least moderate, even if this variability is self-controlled.OBJETIVO: Investigar se ocorre prejuízo à saúde e à vida social com diferentes tipos de horas de trabalho flexíveis e se há relação entre estes efeitos e características específicas das horas de trabalho. MÉTODOS: Foram realizados dois estudos, uma pesquisa em uma empresa (N=660 e outra pela Internet (N=528. O primeiro estudo consistiu de um questionário (papel e lápis aplicado a funcionários sujeitos a diferentes ajustes "típicos" de horas de

  14. Ionospheric effects on terrestrial communications :Working Group 3 overview

    Directory of Open Access Journals (Sweden)

    A. Bourdillon

    2004-06-01

    Full Text Available Telecommunications via ionospheric reflection of radio signals of ground-based transmitters are a traditional area. However, this technique is still in use in telecommunications, broadcasting, etc. Various problems have not yet been solved and some of them were studied in Working Group 3 (WG3. Structure of WG 3 and the terms of reference of its four working packages are described in the introductory paper by Zolesi and Cander (2004. Here we describe the main results achieved in COST 271 in the following areas: i large-scale fluctuations of planetary and gravity waves; ii development of a new type of HF channel simulator; iii geomagnetic storm effects on the F1-region ionosphere; iv the sporadic E-layer and spread-F phenomena; v the HF radio wave propagation over northerly paths; vi how to increase the bit rate in ionospheric radio links. In general, substantial progress was achieved but some problems remain open for future investigations.

  15. Caffeine plus nicotine improves motor function, spatial and non-spatial working memory and functional indices in BALB/c male mice.

    Science.gov (United States)

    Adeniyi, P A; Omatsuli, E P; Akinyemi, A J; Ishola, A O

    2016-12-01

    There is a greater prevalence of cigarette smoking among caffeine dependent individuals. This study therefore sought to assess the effect of nicotine and/or caffeine on some key biochemical indices and neurobehavioural parameters associated with brain function in male mice. Forty male BALB/c mice were divided into 4 groups of 10 animals each; Group A serve as the control and received normal saline (s.c), Group B received 2mg/kg body weight of nicotine (s.c), Group C received 2mg/kg body weight of caffeine (s.c) and Group D received 2mg/kg of nicotine and 2mg/kg of caffeine (s.c). The experiment lasted for 21 days, and then the animals were subjected to behavioral test. Thereafter the animals were sacrificed and their brain isolated for the determination of endothelial nitric oxide (NO) level, acetylcholinesterase (AChE), arginase (Arg) and adenosine deaminase (ADA) activities; as well as some antioxidant indices. Administration of nicotine or caffeine caused a significant (Pcaffeine cognitive properties through a significant increase in non-spatial working memory whereas; it was otherwise on the spatial working memory and motor coordination. Therefore, we can suggest from our present study that caffeine enhances the effect of nicotine either synergistically or additively on memory and motor function and some key biochemical indices associated with brain function in male mice. Copyright © 2016. Published by Elsevier B.V.

  16. Role of work function in field emission enhancement of Au island decorated vertically aligned ZnO nanotapers

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Avanendra [School of Physical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, Odisha (India); Senapati, Kartik, E-mail: kartik@niser.ac.in [School of Physical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, Odisha (India); Kumar, Mohit; Som, Tapobrata [SUNAG Laboratory, Institute of Physics, Bhubaneswar 751005, Odisha (India); Sinha, Anil K. [Indus Synchrotrons Utilization Division, Raja Ramanna Centre for Advanced Technology, Indore 452013, M.P. (India); Sahoo, Pratap K., E-mail: pratap.sahoo@niser.ac.in [School of Physical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, Odisha (India)

    2017-07-31

    Highlights: • Hydrothermally synthesized nanotapers were decorated by gold corrugation using simple evaporation techniques for large area applications. • A significantly enhanced field emission properties of nanotapers were achieved. • The metal induced midgap states formed at the ZnO-Au interface and the reduced effective work function are responsible for low turn-on field. • TUNA measurements revealed a very uniform spatial emission profile in the Au decorated nanotapers. - Abstract: In this report, we demonstrate significantly enhanced field emission properties of ZnO nanotapers achieved via a corrugated decoration of Au. Field emission experiments on these Au-decorated ZnO nanotapers showed emission current densities comparable to the best results in the literature. Au decoration of 5 nm also reduced the effective turn-on field to ∼0.54 V/μm, compared to the as grown ZnO nanotapers, which showed a turn-on field of ∼1.1 V/μm. Tunneling atomic force microscopy measurements revealed a very uniform spatial emission profile in the 5 nm Au decorated nanotapers, which is a basic requirement for any large scale application. We believe that metal induced mid-gap states formed at the ZnO–Au interface are responsible for the observed low turn-on field because such interface states are known to reduce the effective work function. A direct measurement of effective work function using Kelvin probe force microscopy indeed showed more than 1.1 eV drop in the case of 5 nm Au decorated ZnO nanotapers compared to the pristine nanotapers, supporting the above argument.

  17. `Sex' - It's not only Women's Work: A Case for Refocusing on the Functional Role that Sex Plays in Work for both Women and Men.

    Science.gov (United States)

    Uretsky, Elanah

    2015-01-01

    Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `sex work' as a means to legitimize sex as an income generating activity for women involved in prostitution. I show that sex can also serve a functional role in the work-related duties of men seeking economic and political success in contemporary urban China. Men in China utilize sex as one way for demonstrating the loyalty necessary to access state-owned and controlled resources in a market economy governed under a Leninist system. Overall the article demonstrates that reclaiming perception of sex work as a functional rather than behavioral category can expand its use for preventing HIV among the broad subset of people who engage in sex as part of their work.

  18. [Analysis of the effect of lithium salts on cognitive functions].

    Science.gov (United States)

    Dassò, L; Campari, F; Bocelli, G; Mozzani, M; De Risio, C

    1982-01-01

    In this work the authors studied the effects of lithium on memory and reaction times in 7 manic-depressive patients receiving long-term therapy. The results suggest lithium treatment does not change these intellectual functions to any significant extent, comparing the trials of the experimental sessions during the therapy and after two weeks off lithium. Our data mostly agree with the studies of other Authors who used similar experimental methods.

  19. Sex differences in physical and mental functioning of Japanese civil servants: explanations from work and family characteristics.

    Science.gov (United States)

    Sekine, Michikazu; Chandola, Tarani; Martikainen, Pekka; Marmot, Michael; Kagamimori, Sadanobu

    2010-12-01

    Poor physical and mental functioning are more common among women than men and those with disadvantaged work and family characteristics. This study aims to clarify whether sex differences in health functioning can be explained by sex differences in work and family characteristics. The subjects were 3787 civil servants (2525 men and 1262 women), aged 20-65, working in a local government on the west coast of Japan. A questionnaire survey was conducted in January 2003. Low employment grade, high demands, long work hours, shift work, being unmarried, having no young children, high family-to-work conflict and high work-to-family conflict were more common among women than men and were independently associated with poor physical and mental functioning. The age-adjusted odds ratios (ORs) of women for poor health functioning were 1.80 for poor physical functioning and 1.77 for poor mental functioning. When adjusted for employment grade and work characteristics (control, demand, support, work hours, and shift work), the sex differences in health functioning attenuated. When adjusted for family characteristics (family structure and work-family conflicts), the sex differences in health functioning further attenuated and were no longer statistically significant. Sex differences in family characteristics contributed more to sex difference in mental functioning than sex differences in work characteristics. Japan belongs to conservative welfare regimes. In such countries, men are able to concentrate on their work with relative freedom from their family tasks and responsibilities, whereas women feel difficulties in maintaining their work-life balances. Such sex differences in work- and family-related stresses may contribute to sex difference in health. Longitudinal research is necessary to clarify the causal nature of these associations. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. Work-function measurement by high-resolution scanning Kelvin nanoprobe

    Science.gov (United States)

    Cheran, Larisa-Emilia; Johnstone, Sherri; Sadeghi, Saman; Thompson, Michael

    2007-03-01

    Nanoscience promises to transform today's world in the same way that integrated semiconductor devices transformed the world of electronics and computation. In the post-genomic era, the greatest challenge is to make connections between the structures and functions of biomolecules at the nanometre-scale level in order to underpin the understanding of larger scale systems in the fields of human biology and physiology. To achieve this, instruments with new capabilities need to be researched and developed, with particular emphasis on new levels of sensitivity, precision and resolution for biomolecular analysis. This paper describes an instrument able to analyse structures that range from tenths of a nanometre (proteins, DNA) to micron-scale structures (living cells), which can be investigated non-destructively in their normal state and subsequently in chemical- or biochemical-modified conditions. The high-resolution scanning Kelvin nanoprobe (SKN) measures the work-function changes at molecular level, instigated by local charge reconfiguration due to translational motion of mobile charges, dipolar relaxation of bound charges, interfacial polarization and structural and conformational modifications. In addition to detecting surface electrical properties, the instrument offers, in parallel, the surface topographic image, with nanometre resolution. The instrument can also be used to investigate subtle work function/topography variations which occur in, for example, corrosion, contamination, adsorption and desorption of molecules, crystallographic studies, mechanical stress studies, surface photovoltaic studies, material science, biocompatibility studies, microelectronic characterization in semiconductor technology, oxide and thin films, surface processing and treatments, surfaces and interfaces characterization. This paper presents the design and development of the instrument, the basic principles of the method and the challenges involved to achieve nanometric resolution

  1. Functional and morphological alterations associated with working memory dysfunction in patients with generalized anxiety disorder.

    Science.gov (United States)

    Moon, Chung-Man; Jeong, Gwang-Woo

    2017-03-01

    Background Generalized anxiety disorder (GAD) has been related to functional brain activities and structural brain abnormalities. Purpose To investigate the neural mechanism on working memory dysfunction in patients with GAD in terms of the combined functional and morphological brain abnormalities. Material and Methods Patients with GAD and healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted (T1W) magnetic resonance imaging (MRI) and functional MRI (fMRI). In this study, fMRI and voxel-based morphometry (VBM) were used for assessing the differential brain activation patterns, as well as for comparing the morphological alterations between the two groups. Results In response to the neutral distractors, the patients showed significantly lower activities in the regions of the fusiform gyrus (FuG), superior parietal gyrus (SPG), precuneus (PCu), superior occipital gyrus (SOG), lingual gyrus (LiG), cuneus (Cun), calcarine cortex (CaC), parahippocampal gyrus (PHG) and cerebellar cortex (Cb) compared to the controls. In response to the anxiety-inducing distractors, the patients showed significantly higher activity in the hippocampus and lower activities in the regions of the dorsolateral prefrontal cortex (DLPFC), FuG, SPG, PCu, SOG, and Cb. Also, the patients showed a significant reduction of the white matter volumes in the DLPFC, anterior limb of the internal capsule (ALIC) and midbrain. Conclusion This study provides the first evidence for the association between the morphometric alterations and functional deficit in the working memory processing with the neutral and anxiety-inducing distractors in GAD patients. These findings would be helpful to understand the neural mechanisms on working memory impairment in connection with GAD symptoms.

  2. Working memory dysfunction in obsessive-compulsive disorder: a neuropsychological and functional MRI study.

    Science.gov (United States)

    Nakao, Tomohiro; Nakagawa, Akiko; Nakatani, Eriko; Nabeyama, Maiko; Sanematsu, Hirokuni; Yoshiura, Takashi; Togao, Osamu; Tomita, Mayumi; Masuda, Yusuke; Yoshioka, Kazuko; Kuroki, Toshihide; Kanba, Shigenobu

    2009-05-01

    Previous neuropsychological studies indicate that OCD subtypes such as checking rituals might be associated with a working memory deficit. On the other hand, functional neuroimaging studies found functional abnormalities of the frontal cortex and subcortical structures in OCD. Combined with functional imaging method, we applied neuropsychological batteries to demonstrate a working memory deficit in OCD by comparison with normal controls. In addition, working memory and brain activation were further examined with symptom-based analysis. Forty patients with OCD and 25 normal controls were examined using neuropsychological tests including the WAIS-R, WCST, WMS-R, and R-OCFT and functional MRI (fMRI) during the N-back task including 0- and 2-back task. On fMRI, the brain regions activated during the performance and the differences in the activation between patients and controls were identified. Additional analyses of severity and subtypes were conducted by using Y-BOCS severity score, symptom-checklist and Leckman's four-factor model, respectively. On the neuropsychological tests, the OCD patients had significantly lower scores on the delayed recall section of the WMS-R and the immediate recall section of the R-OCFT compared to the controls. On fMRI, the patients showed greater activation in the right dorsolateral prefrontal cortex (DLPFC), left superior temporal gyrus (STG), left insula, and cuneus during two-back task compared to the controls. Right orbitofrontal cortex activity showed a significant positive correlation with Y-BOCS scores in OCD. Furthermore, patients with obsessions/checking rituals (n=10) showed severer memory deficits and decreased activity in the postcentral gyrus than patients with cleanliness/washing rituals (n=14). In conclusion, we found neuropsychological dysfunction and brain abnormalities in OCD. Furthermore, our results suggested that symptom severity and symptom subtype such as obsessions/checking might affect neuropsychological

  3. The Function of Verbal Mediation in Comprehending Works of Art: A Comparison of Three Cultures.

    Science.gov (United States)

    Koroscik, Judith S.; And Others

    1988-01-01

    The purpose of this study was to determine the extent to which cultural biases contribute to the effect of verbalization on comprehending the structures and meaning of art in the United States, Brazil, and Egypt. Findings indicate a verbal task instructing viewers to generate their own title for each work promoted superior retention in all three…

  4. Household Work Complexity, Intellectual Functioning, and Self-Esteem in Men and Women

    Science.gov (United States)

    Caplan, Leslie J.; Schooler, Carmi

    2006-01-01

    Using data from a U.S. longitudinal investigation of psychological effects of occupational conditions (a project of the National Institute of Mental Health's unit on Socioenvironmental Studies), we examined the relationship between the complexity of household work and 2 psychological variables: intellectual flexibility and self-esteem.…

  5. Functional neuroimaging of working memory in survivors of childhood brain tumors and healthy children: Associations with coping and psychosocial outcomes.

    Science.gov (United States)

    Robinson, Kristen E; Pearson, Matthew M; Cannistraci, Christopher J; Anderson, Adam W; Kuttesch, John F; Wymer, Kevin; Smith, Samantha E; Park, Sohee; Compas, Bruce E

    2015-01-01

    Pediatric brain tumors are the second most common cancer diagnosis in individuals under age 20 and research has documented significant neurocognitive, psychosocial, and emotional late effects. Associations among these deficits have not been adequately considered and the role of survivors' coping with stress in relation to deficits is unknown. Further, research has yet to examine neurobiological processes related to neurocognitive, psychosocial, and emotional difficulties in survivors through the use of functional neuroimaging. Questionnaire measures and functional neuroimaging were used to examine the neurocognitive, psychosocial, and emotional functioning and coping responses of survivors of pediatric brain tumors (N = 17; age 8-16) and healthy children (N = 15). Survivors experienced elevated levels of psychosocial and behavioral/emotional difficulties relative to healthy controls and normative data. Increases in brain activation in prefrontal and other anterior regions in response to a working memory task were associated with better psychosocial functioning, use of engagement coping strategies, and less use of disengagement coping strategies. Regression analyses suggest coping accounts for a significant portion of the association between brain activation and behavioral/emotional functioning. This study extends late-effects research by examining neurobiological processes associated with psychosocial and emotional difficulties. These findings contribute to our understanding of difficulties in survivors and provide a foundation for research exploring these associations and mediators of deficits in future longitudinal studies.

  6. Reliability and validity of Functional Capacity Evaluation methods: a systematic review with reference to Blankenship system, Ergos work simulator, Ergo-Kit and Isernhagen work system

    NARCIS (Netherlands)

    Gouttebarge, Vincent; Wind, Haije; Kuijer, P. Paul F. M.; Frings-Dresen, Monique H. W.

    2004-01-01

    Objectives: Functional Capacity Evaluation methods (FCE) claim to measure the functional physical ability of a person to perform work-related tasks. The purpose of the present study was to systematically review the literature on the reliability and validity of four FCEs: the Blankenship system (BS),

  7. Leadership effectiveness: a supervisor's approach to manage return to work.

    Science.gov (United States)

    Schreuder, J A H; Groothoff, J W; Jongsma, D; van Zweeden, N F; van der Klink, J J L; Roelen, C A M

    2013-09-01

    To investigate adaptive leadership in relation to personnel sickness absence (SA). In situational leadership, supervisors are effective if they adapt their leadership style appropriately to a given situation. A managerial reorganization in a Dutch hospital with reassignment of supervisors provided the opportunity to compare SA in the same wards while under the leadership of different supervisors. Leadership effectiveness was measured with the Leader Effectiveness and Adaptability Description (LEAD). Personnel SA was retrieved from employer's records and cumulated at the individual level, distinguishing between short-term (1-7 day) and long-term (>7 days) SA. Cumulated SA days and mean SA lengths before and after managerial reorganization were compared at the individual level by using non-parametric paired statistical analyses. Employer's costs to compensate sick-listed employees' salaries before and after reorganization were cumulated and compared at ward level by using non-parametric statistics. 6 wards (N = 403) retained the same supervisor, 6 wards (N = 504) were assigned more effective supervisors, and 4 wards (N = 184) got less effective supervisors than the ones before reorganization. Cumulated short-term SA days and lengths did not change with leadership effectiveness. Employees who got more effective supervisors had fewer long-term SA days and shorter long-term SA lengths than before reorganization. More effective supervisors saved an average of 21,368 Euros per ward, particularly due to less long-term SA. Long-term SA was shorter after employees got more effective supervisors. Adaptive supervisors can facilitate return to work and save SA costs by providing the right type of support to sick-listed employees.

  8. Working Memory and Executive Function Decline across Normal Aging, Mild Cognitive Impairment, and Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Anna-Mariya Kirova

    2015-01-01

    Full Text Available Alzheimer’s disease (AD is a progressive neurodegenerative disease marked by deficits in episodic memory, working memory (WM, and executive function. Examples of executive dysfunction in AD include poor selective and divided attention, failed inhibition of interfering stimuli, and poor manipulation skills. Although episodic deficits during disease progression have been widely studied and are the benchmark of a probable AD diagnosis, more recent research has investigated WM and executive function decline during mild cognitive impairment (MCI, also referred to as the preclinical stage of AD. MCI is a critical period during which cognitive restructuring and neuroplasticity such as compensation still occur; therefore, cognitive therapies could have a beneficial effect on decreasing the likelihood of AD progression during MCI. Monitoring performance on working memory and executive function tasks to track cognitive function may signal progression from normal cognition to MCI to AD. The present review tracks WM decline through normal aging, MCI, and AD to highlight the behavioral and neurological differences that distinguish these three stages in an effort to guide future research on MCI diagnosis, cognitive therapy, and AD prevention.

  9. Effects of Physical (Inactivity on Platelet Function

    Directory of Open Access Journals (Sweden)

    Stefan Heber

    2015-01-01

    Full Text Available As platelet activation is closely related to the liberation of growth factors and inflammatory mediators, platelets play a central role in the development of CVD. Virtually all cardiovascular risk factors favor platelet hyperreactivity and, accordingly, also physical (inactivity affects platelet function. Within this paper, we will summarize and discuss the current knowledge on the impact of acute and habitual exercise on platelet function. Although there are apparent discrepancies regarding the reported effects of acute, strenuous exercise on platelet activation, a deeper analysis of the available literature reveals that the applied exercise intensity and the subjects’ cardiorespiratory fitness represent critical determinants for the observed effects. Consideration of these factors leads to the summary that (i acute, strenuous exercise can lead to platelet activation, (ii regular physical activity and/or physical fitness diminish or prevent platelet activation in response to acute exercise, and (iii habitual physical activity and/or physical fitness also favorably modulate platelet function at physical rest. Notably, these effects of exercise on platelet function show obvious similarities to the well-recognized relation between exercise and the risk for cardiovascular events where vigorous exercise transiently increases the risk for myocardial infarction and a physically active lifestyle dramatically reduces cardiovascular mortality.

  10. Validating Age-Related Functional Imaging Changes in Verbal Working Memory with Acute Stroke

    Directory of Open Access Journals (Sweden)

    Timothy B. Meier

    2011-01-01

    Full Text Available Functional imaging studies consistently find that older adults recruit bilateral brain regions in cognitive tasks that are strongly lateralized in younger adults, a characterization known as the Hemispheric Asymmetry Reduction in Older Adults model. While functional imaging displays what brain areas are active during tasks, it cannot demonstrate what brain regions are necessary for task performance. We used behavioral data from acute stroke patients to test the hypothesis that older adults need both hemispheres for a verbal working memory task that is predominantly left-lateralized in younger adults. Right-handed younger (age ≥ 50, n = 7 and older adults (age > 50, n = 21 with acute unilateral stroke, as well as younger (n = 6 and older (n = 13 transient ischemic attack (TIA patients, performed a self-paced verbal item-recognition task. Older patients with stroke to either hemisphere had a higher frequency of deficits in the verbal working memory task compared to older TIA patients. Additionally, the deficits in older stroke patients were mainly in retrieval time while the deficits in younger stroke patients were mainly in accuracy. These data suggest that bihemispheric activity is necessary for older adults to successfully perform a verbal working memory task.

  11. Effects of posture on postoperative pulmonary function

    DEFF Research Database (Denmark)

    Nielsen, K G; Holte, Kathrine; Kehlet, H

    2003-01-01

    BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed....... METHODS: Review of controlled, clinical trials evaluating postoperative pulmonary function in patients positioned in the supine vs. the sitting or standing position and patients positioned in the supine vs. the lateral position. Data were obtained from a search in the Medline and Cochrane databases (1966...

  12. DHA effects in brain development and function

    DEFF Research Database (Denmark)

    Lauritzen, Lotte; Brambilla, Paola; Mazzocchi, Allesandra

    2016-01-01

    the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies...... justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects...... a role of DHA in cognitive decline and in relation to major psychiatric disorders....

  13. Speed and capacity of working memory and executive function in schizophrenia compared to unipolar depression

    Directory of Open Access Journals (Sweden)

    Wolfgang Trapp

    2017-12-01

    Full Text Available Schizophrenia is associated with deficits in working memory (WM and executive functioning (EF that are present from prodrome to chronic stages of the disease and are related to social and occupational functioning. Recent empirical findings suggest that schizophrenia patients might suffer from a specific speed deficit regarding WM operations that also affects EF. To test this hypothesis, executive functioning (EF and working memory (WM performance of 20 schizophrenia (SC patients, 20 patients suffering from Major Depressive Disorder (MDD and 40 healthy control (HC subjects were compared. While schizophrenia patients performed worse in the measure of EF, no difference between the SC and the MDD patients was found regarding WM capacity. However, the SC group was shown to have an impaired speed in encoding, retrieval and manipulation of WM contents compared to the HC group whereas the MDD group showed no such deficit. Furthermore, while in the MDD group only WM capacity was linked to EF performance, in the SC group EF was determined by both WM capacity and WM speed. Hence, increasing the speed of WM operations might be a fruitful target for future therapeutic interventions, and assessing not only the capacity but also the speed of WM might be helpful in identifying candidates for endophenotypic cognitive markers of SC.

  14. Storage and Processing Working Memory Functions in Alzheimer-Type Dementia

    Directory of Open Access Journals (Sweden)

    T. Vecchi

    1999-01-01

    Full Text Available A selective deterioration of working memory functions has been suggested as an explanation of the cognitive decay occurring in normal ageing as well as in Alzheimer-type dementia. Recent studies have highlighted that elderly people’s limitations in working memory functions may be better interpreted when analysing the specific characteristics of the cognitive process (i.e., passive storage or active manipulation of information. In the present study, we have adapted a procedure used to investigate age-related memory modifications, involving both verbal and visuo-spatial material in tasks tapping passive and active processes, to investigate the deterioration associated with Alzheimer's disease. A group of Alzheimer patients in the early stages of the disease were matched to a control group of healthy elderly. Results show that Alzheimer patients performed less accurately than the control group in all tasks. However, the deficit was maximised in the case of active processes, regardless of the type of material used (verbal or visuo-spatial. These data highlight the importance of considering the amount of active processing as the key variable when interpreting the decay in cognitive functions in the early stages of Alzheimer’s disease.

  15. Night Shift Work and Its Health Effects on Nurses.

    Science.gov (United States)

    Books, Candie; Coody, Leon C; Kauffman, Ryan; Abraham, Sam

    The purpose of this research was to study night shift work and its health effects on nurses. This was a quantitative study using descriptive design; it also incorporated three qualitative open-ended questions to complement the study. The data were collected using Survey Monkey, with an Internet-based confidential data collection tool. The population of relevance to this study was nurses employed in hospital settings in the United States. E-mail addresses and Facebook were used to recruit participants. Results indicated that there is an increased risk of sleep deprivation, family stressors, and mood changes because of working the night shift. Rotating shifts were mentioned as a major concern for night shift nurses. Respondents agreed that complaints about fatigue and fatigue-related illnesses in night shift workers were ignored. There was also a general perception among nurses working the night shift that sleep deprivation leads to negative health consequences including obesity; however, they were not as high a concern as rotating shifts or fatigue.

  16. The Cognitive Symptom Checklist-Work in cancer patients is related with work functioning, fatigue and depressive symptoms: a validation study.

    Science.gov (United States)

    Dorland, H F; Abma, F I; Roelen, C A M; Smink, A; Feuerstein, M; Amick, B C; Ranchor, A V; Bültmann, U

    2016-06-01

    The study objectives are to translate the 21-item Cognitive Symptom Checklist-Work (CSC-W21) to Dutch (CSC-W DV) and to validate the CSC-W DV in working cancer patients. The CSC-W21 was cross-culturally translated and adapted to a Dutch version. In this 19-item version, the dichotomous response option was changed to an ordinal five-point scale. A validation study of the CSC-W DV was conducted among cancer patients who had returned to work during or following cancer treatment. Internal consistency (Cronbach's α), structural validity (exploratory factor analysis) and construct validity (hypothesis testing) were evaluated. In a cohort of 364 cancer patients, 341 (94 %) completed the CSC-W DV (aged 50.6 ± 8.6 years, 60 % women). Exploratory factor analysis revealed two subscales 'working memory' and 'executive function'. The internal consistency of the total scale and subscales was high (Cronbach's α = 0.93-0.95). Hypothesis testing showed that self-reported cognitive limitations at work were related to work functioning (P < 0.001), fatigue (P = 0.001) and depressive symptoms (P < 0.001), but not to self-rated health (P = 0.14). The CSC-W DV showed high internal consistency and reasonable construct validity for measuring work-specific cognitive symptoms in cancer patients. The CSC-W DV was associated in expected ways with work functioning, fatigue and depressive symptoms. It is important to enhance knowledge about cognitive symptoms at work in cancer patients, to guide and support cancer patients as good as possible when they are back at work and to improve their work functioning over time.

  17. Effect of the Work Environment on Using Time at Work to Exercise.

    Science.gov (United States)

    Bale, Jeffrey M; Gazmararian, Julie A; Elon, Lisa

    2015-01-01

    To determine whether workload, job satisfaction, and flexible schedules are predictive of using time at work to exercise. The study design was the quantitative analysis of the time at work to exercise intervention of a cluster-randomized controlled trial. The study took place at Emory University, Atlanta, Georgia. Subjects comprised 188 full- and part-time faculty and staff (57% female). Employees were randomized into different intervention groups, and analysis focused on employees who were provided 30 minutes of time at work to exercise. Time at work to exercise at was measured 9 months, and work environment characteristics were measured at baseline. Logistic regression modeling using generalized estimating equation analysis was used to account for departmental clustering. Time at work to exercise was used by 45% of participants. Participants who felt comfortable taking time off work to exercise were 2.8 times more likely to use time to exercise than those who did not feel comfortable taking time off (95% confidence interval: 1.3 to 6.1). Participants who reported too much work were .3 times less likely to exercise (95% confidence interval: 0.2 to 0.7). Job satisfaction and the ability to take time off for personal matters were not significantly associated with using time to exercise. The results support the hypothesis that individuals with a supportive work environment would be more likely to use time at work to exercise. Workload and having time during the day are more important than job satisfaction.

  18. Improving work functioning and mental health of health care employees using an e-mental health approach to workers' health surveillance: pretest-posttest study.

    Science.gov (United States)

    Ketelaar, Sarah M; Nieuwenhuijsen, Karen; Bolier, Linda; Smeets, Odile; Sluiter, Judith K

    2014-12-01

    Mental health complaints are quite common in health care employees and can have adverse effects on work functioning. The aim of this study was to evaluate an e-mental health (EMH) approach to workers' health surveillance (WHS) for nurses and allied health professionals. Using the waiting-list group of a previous randomized controlled trial with high dropout and low compliance to the intervention, we studied the pre- and posteffects of the EMH approach in a larger group of participants. We applied a pretest-posttest study design. The WHS consisted of online screening on impaired work functioning and mental health followed by online automatically generated personalized feedback, online tailored advice, and access to self-help EMH interventions. The effects on work functioning, stress, and work-related fatigue after 3 months were analyzed using paired t tests and effect sizes. One hundred and twenty-eight nurses and allied health professionals participated at pretest as well as posttest. Significant improvements were found on work functioning (p = 0.01) and work-related fatigue (p Work functioning had relevantly improved in 30% of participants. A small meaningful effect on stress was found (Cohen d = .23) in the participants who had logged onto an EMH intervention (20%, n = 26). The EMH approach to WHS improves the work functioning and mental health of nurses and allied health professionals. However, because we found small effects and participation in the offered EMH interventions was low, there is ample room for improvement.

  19. The role of working memory in the metaphor interference effect.

    Science.gov (United States)

    Pierce, Russell S; Maclaren, Rick; Chiappe, Dan L

    2010-06-01

    Participants took longer to judge that metaphors (e.g., an insult is a razor, memory is a warehouse) were literally false than to judge that scrambled sentences (e.g., an insult is a warehouse) were false. This result is the metaphor interference effect (MIE). It demonstrates that metaphor processing is automatic. In this experiment, we found that the magnitude of the MIE is predicted by working memory (WM) capacity, with higher WM yielding a smaller MIE. This suggests that although metaphor comprehension is automatic, the early processing of metaphors is controllable by executive mechanisms. We relate our results to Kintsch's (2000, 2001) predication model. Specifically, we suggest that mechanisms of WM influence metaphor processing by affecting the effectiveness of the construction-integration process that identifies common properties between topics and vehicles. WM also influences the speed with which meanings are identified as literal or figurative.

  20. Measuring positive and negative occupational states at work: A structural and differential item functioning analysis

    Directory of Open Access Journals (Sweden)

    Marie Barbier

    2012-04-01

    Full Text Available This article reports on the structural validation of the Positive and Negative Occupational States Inventory, which measures positive and negative states at work. The first aim was to check for the impact of item wording. The second aim was to check for interactions between items and gender or age. More than 31,000 data collected in 63 Belgian and French companies were used. Results of structural equation show that meaning better represents the tool structure than wording, at least for the negative occupational state. Results of differential item functioning analyses show that gender and age have no impact on workers' answers. It is concluded that future studies should check for the impact of initial NOSI and POSI levels. Future studies should also examine reciprocal relationships between working conditions on the one hand and NOSI and POSI on the other.

  1. Utility of the International Classification of Functioning, Disability and Health (ICF) for educational psychologists’ work

    Science.gov (United States)

    Aljunied, Mariam; Frederickson, Norah

    2014-01-01

    Despite embracing a bio-psycho-social perspective, the World Health Organization’s International Classification of Functioning, Disability and Health (ICF) assessment framework has had limited application to date with children who have special educational needs (SEN). This study examines its utility for educational psychologists’ work with children who have Autism Spectrum Disorders (ASD). Mothers of 40 children with ASD aged eight to 12 years were interviewed using a structured protocol based on the ICF framework. The Diagnostic Interview for Social and Communication Disorder (DISCO) was completed with a subset of 19 mothers. Internal consistency and inter-rater reliability of the interview assessments were found to be acceptable and there was evidence for concurrent and discriminant validity. Despite some limitations, initial support for the utility of the ICF model suggests its potential value across educational, health and care fields. Further consideration of its relevance to educational psychologists in new areas of multi-agency working is warranted. PMID:26157197

  2. Differential effects of enriched environment at work on cognitive decline in old age.

    Science.gov (United States)

    Then, Francisca S; Luck, Tobias; Luppa, Melanie; König, Hans-Helmut; Angermeyer, Matthias C; Riedel-Heller, Steffi G

    2015-05-26

    The aim of the present study was to investigate how different mentally demanding work conditions during the professional life-i.e., enriched environments at work-might influence the rate of cognitive decline in old age. Individuals (n = 1,054) of the Leipzig Longitudinal Study of the Aged, a representative population-based cohort study of individuals aged 75 years and older, underwent cognitive testing via the Mini-Mental State Examination (MMSE) in up to 6 measurement waves. Type and level of mentally demanding work conditions in the participants' former professional life were classified based on the O*NET job descriptor database. In multivariate mixed-model analyses (controlling for sociodemographic and health-related factors), a high level of mentally demanding work tasks stimulating verbal intelligence was significantly associated with a better cognitive functioning at baseline (on average 5 MMSE points higher) as well as a lower rate of cognitive decline (on average 2 MMSE points less) over the 8-year follow-up period compared with a low level. The rate of cognitive decline in old age was also significantly lower (on average 3 MMSE points less) in individuals who had a high level of mentally demanding work tasks stimulating executive functions than those who had a low level. The results suggest that a professional life enriched with work tasks stimulating verbal intelligence and executive functions may help to sustain a good cognitive functioning in old age (75+ years). The findings thus emphasize that today's challenging work conditions may also promote positive health effects. © 2015 American Academy of Neurology.

  3. Polystyrene-block-Poly(ionic liquid) Copolymers as Work Function Modifiers in Inverted Organic Photovoltaic Cells.

    Science.gov (United States)

    Park, Jong Baek; Isik, Mehmet; Park, Hea Jung; Jung, In Hwan; Mecerreyes, David; Hwang, Do-Hoon

    2018-02-07

    Interfacial layers play a critical role in building up the Ohmic contact between electrodes and functional layers in organic photovoltaic (OPV) solar cells. These layers are based on either inorganic oxides (ZnO and TiO 2 ) or water-soluble organic polymers such as poly[(9,9-dioctyl-2,7-fluorene)-alt-(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)] and polyethylenimine ethoxylated (PEIE). In this work, we have developed a series of novel poly(ionic liquid) nonconjugated block copolymers for improving the performance of inverted OPV cells by using them as work function modifiers of the indium tin oxide (ITO) cathode. Four nonconjugated polyelectrolytes (n-CPEs) based on polystyrene and imidazolium poly(ionic liquid) (PSImCl) were synthesized by reversible addition-fragmentation chain transfer polymerization. The ratio of hydrophobic/hydrophilic block copolymers was varied depending on the ratio of polystyrene to the PSImCl block. The ionic density, which controls the work function of the electrode by forming an interfacial dipole between the electrode and the block copolymers, was easily tuned by simply changing the PSImCl molar ratio. The inverted OPV device with the ITO/PS 29 -b-PSImCl 60 cathode achieved the best power conversion efficiency (PCE) of 7.55% among the synthesized block copolymers, exhibiting an even higher PCE than that of the reference OPV device with PEIE (7.30%). Furthermore, the surface properties of the block copolymers films were investigated by contact angle measurements to explore the influence of the controlled hydrophobic/hydrophilic characters on the device performances.

  4. Modelling the effect of perceived interdependence among mental healthcare professionals on their work role performance.

    Science.gov (United States)

    Markon, Marie-Pierre; Chiocchio, François; Fleury, Marie-Josée

    2017-07-01

    The purpose of mental healthcare system reform was to enhance service efficiency by strengthening primary mental healthcare and increasing service integration in communities. Reinforcing interprofessional teamwork also intended to address the extensive and multidimensional needs of patients with mental disorders by bringing together a broader array of expertise. In this context, mental healthcare professionals (MHCPs) from various health and social care professions are more interdependent in many aspects of their work (tasks, resources, and goals). We wanted to examine the effect of perceived interdependence among MHCPs on their work role performance in the context of mental healthcare. For this purpose, we developed and tested a model coherent with the Input-Mediator-Outcome-Input (IMOI) framework of team effectiveness. Data from questionnaires administered to 315 MHCPs from four local health service networks in Quebec, Canada were analysed through structural equation modelling and mediation analysis. The structural equation model provided a good fit for the data and explained 51% of the variance of work role performance. Perceived collaboration, confidence in the advantages of interprofessional collaboration, involvement in the decision process, knowledge sharing, and satisfaction with the nature of the work partially mediated the effect of perceived interdependence among team members on work role performance. Therefore, perceived interdependence among team members had a positive impact on the work role performance of MHCPs mostly through its effect on favourable team functioning features. This implies, in practice, that increased interdependence of MHCPs would be more likely to truly enhance work role performance if team-based interventions to promote collaborative work and interprofessional teaching and training programs to support work within interprofessional teams were jointly implemented. Participation in the decision process and knowledge sharing should

  5. The association between working alliance and clinical and functional outcome in a cohort of 400 patients with first-episode psychosis

    DEFF Research Database (Denmark)

    Melau, Marianne; Harder, Susanne; Jeppesen, Pia

    2015-01-01

    working alliance was associated with fewer clinical symptoms and better social functioning. METHOD: In a cross-sectional design, patients with first-episode schizophrenia spectrum disorders (ICD-10, F20-29) were included after 18 months of treatment (N = 400). Baseline data were collected between June...... 2009 and December 2011. Symptoms were assessed using Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS), Global Assessment of Functioning (GAF), Brief Assessment of Cognition in Schizophrenia (BACS), Working Alliance Inventory (WAI), and General.......01), and between working alliance and better social functioning (β = 1.45; 95% CI, 0.55 to 2.36). General self-efficacy mediated the effect of working alliance, explaining 14%-18% of the variance in associated outcomes. Global level of cognitive functioning, compliance, and self-efficacy influenced clinical...

  6. Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based sample of Working Adults

    Directory of Open Access Journals (Sweden)

    Cecilia Ulrika Dagsdotter Stenfors

    2016-10-01

    Full Text Available Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD, and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulationThe aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women, from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability measures, including the Standard Deviation of NN, here heart beats (SDNN, root of the mean squares of successive differences (RMSSD, high frequency (HF power band from spectral analyses, and QT variability index (QTVI, a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by 7 neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables and mental health symptoms.Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder, only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity. Conclusion: Poorer cardiovascular autonomic regulation in terms of lower SDNN & RMSSD and higher QTVI was associated with poorer

  7. Change in the thermionic work function of semiconductor powders exposed to electromagnetic radiation

    Science.gov (United States)

    Bourasseau, S.; Martin, J. R.; Juillet, F.; Teichner, S. J.

    1977-01-01

    The variations of the thermoelectronic work function of titanium dioxide, submitted to an ultraviolet or visible and infrared radiation, in the presence of oxygen, are studied by the vibrating condenser method. It is shown that during the ultraviolet irradiation, a desorption of a first species of oxygen simultaneously occurs with the adsorption of a second species of oxygen and that this phenomenon is found for any structure of TiO2 (anatase or rutile) any texture, oxygen pressure, radiation intensity, and nature of introduced dopes.

  8. Transparent Conducting Oxides for Photovoltaics: Manipulation of Fermi Level, Work Function and Energy Band Alignment

    Directory of Open Access Journals (Sweden)

    Diana E. Proffit

    2010-11-01

    Full Text Available Doping limits, band gaps, work functions and energy band alignments of undoped and donor-doped transparent conducting oxides Zn0, In2O3, and SnO2 as accessed by X-ray and ultraviolet photoelectron spectroscopy (XPS/UPS are summarized and compared. The presented collection provides an extensive data set of technologically relevant electronic properties of photovoltaic transparent electrode materials and illustrates how these relate to the underlying defect chemistry, the dependence of surface dipoles on crystallographic orientation and/or surface termination, and Fermi level pinning.

  9. Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based Sample of Working Adults.

    Science.gov (United States)

    Stenfors, Cecilia U D; Hanson, Linda M; Theorell, Töres; Osika, Walter S

    2016-01-01

    Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV) health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD), and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulation. The aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women), from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability (HRV) measures, including the Standard Deviation of NN, here heart beats (SDNN), root of the mean squares of successive differences (RMSSD), high frequency (HF) power band from spectral analyses, and QT variability index (QTVI), a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by seven neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables, and mental health symptoms. Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting, and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder), only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity. Conclusion: Poorer CV autonomic regulation in terms of lower SDNN and RMSSD and higher QTVI was associated with poorer executive

  10. Attention and Working Memory in Adolescents with Autism Spectrum Disorder: A Functional MRI Study.

    Science.gov (United States)

    Rahko, Jukka S; Vuontela, Virve A; Carlson, Synnöve; Nikkinen, Juha; Hurtig, Tuula M; Kuusikko-Gauffin, Sanna; Mattila, Marja-Leena; Jussila, Katja K; Remes, Jukka J; Jansson-Verkasalo, Eira M; Aronen, Eeva T; Pauls, David L; Ebeling, Hanna E; Tervonen, Osmo; Moilanen, Irma K; Kiviniemi, Vesa J

    2016-06-01

    The present study examined attention and memory load-dependent differences in the brain activation and deactivation patterns between adolescents with autism spectrum disorders (ASDs) and typically developing (TD) controls using functional magnetic resonance imaging. Attentional (0-back) and working memory (WM; 2-back) processing and load differences (0 vs. 2-back) were analysed. WM-related areas activated and default mode network deactivated normally in ASDs as a function of task load. ASDs performed the attentional 0-back task similarly to TD controls but showed increased deactivation in cerebellum and right temporal cortical areas and weaker activation in other cerebellar areas. Increasing task load resulted in multiple responses in ASDs compared to TD and in inadequate modulation of brain activity in right insula, primary somatosensory, motor and auditory cortices. The changes during attentional task may reflect compensatory mechanisms enabling normal behavioral performance. The inadequate memory load-dependent modulation of activity suggests diminished compensatory potential in ASD.

  11. Role of work function in field emission enhancement of Au island decorated vertically aligned ZnO nanotapers

    Science.gov (United States)

    Singh, Avanendra; Senapati, Kartik; Kumar, Mohit; Som, Tapobrata; Sinha, Anil K.; Sahoo, Pratap K.

    2017-07-01

    In this report, we demonstrate significantly enhanced field emission properties of ZnO nanotapers achieved via a corrugated decoration of Au. Field emission experiments on these Au-decorated ZnO nanotapers showed emission current densities comparable to the best results in the literature. Au decoration of 5 nm also reduced the effective turn-on field to ∼0.54 V/μm, compared to the as grown ZnO nanotapers, which showed a turn-on field of ∼1.1 V/μm. Tunneling atomic force microscopy measurements revealed a very uniform spatial emission profile in the 5 nm Au decorated nanotapers, which is a basic requirement for any large scale application. We believe that metal induced mid-gap states formed at the ZnO-Au interface are responsible for the observed low turn-on field because such interface states are known to reduce the effective work function. A direct measurement of effective work function using Kelvin probe force microscopy indeed showed more than 1.1 eV drop in the case of 5 nm Au decorated ZnO nanotapers compared to the pristine nanotapers, supporting the above argument.

  12. Effect of PET functionalization in composites of

    Directory of Open Access Journals (Sweden)

    Cristina Cazan

    2017-03-01

    Full Text Available The functionalization of polyethylene terephthalate (PET from tire rubber–PET–high density polyethylene (HDPE composites represents a key strategy for improving the composite properties. This is a practical and effective method to improve the interface between matrix (waste tire rubber and fillers (waste PET and HDPE. By PET functionalization, adherence and surface properties of composite materials can be controlled. PET functionalization was performed with polyethylene glycol (PEG 400, 1% and sodium dodecyl sulphate (SDS 1%. The characterization of the components and composite are discussed in terms of surface energy values (evaluated from water contact angle measurements and surface morphology by using scanning electron microscopy (SEM. The structural and conformational changes were investigated by Fourier Transform Infrared (FTIR Spectroscopy while the crystalline structure was studied by X-ray diffraction (XRD. The improved interfacial adhesion, thermal stability and mechanical properties (stress–strain, compression and impact resistance of the composites are correlated with the PET functionalization, with non-ionic (PEG and an anionic surfactant (SDS. The results proved that the interface properties are improved by functionalization of PET. The best mechanical properties were recorded at 30 min moulding. The samples with 45% PET–SDS showed the best combination of mechanical properties: tensile strength (1.56 N/mm2, impact strength (43.72 kJ/m2 and compression (158.78 N/mm2.

  13. The effect of cannabis use on memory function: an update

    Directory of Open Access Journals (Sweden)

    Schoeler T

    2013-01-01

    Full Text Available Tabea Schoeler, Sagnik BhattacharyyaDepartment of Psychosis Studies, King's College London, Institute of Psychiatry, London, UKAbstract: Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (Δ9-THC and cannabidiol (CBD, the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of Δ9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in Δ9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis

  14. The effect of cannabis use on memory function: an update.

    Science.gov (United States)

    Schoeler, Tabea; Bhattacharyya, Sagnik

    2013-01-01

    Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD), the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of Δ9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in Δ9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis-induced memory impairments occur and to elucidate underlying neurobiological mechanisms.

  15. The effect of cannabis use on memory function: an update

    Science.gov (United States)

    Schoeler, Tabea; Bhattacharyya, Sagnik

    2013-01-01

    Investigating the effects of cannabis use on memory function appears challenging. While early observational investigations aimed to elucidate the longer-term effects of cannabis use on memory function in humans, findings remained equivocal and pointed to a pattern of interacting factors impacting on the relationship between cannabis use and memory function, rather than a simple direct effect of cannabis. Only recently, a clearer picture of the chronic and acute effects of cannabis use on memory function has emerged once studies have controlled for potential confounding factors and started to investigate the acute effects of delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD), the main ingredients in the extract of the cannabis plant in pharmacological challenge experiments. Relatively consistent findings have been reported regarding the acute impairments induced by a single dose of Δ9-THC on verbal and working memory. It is unclear whether they may persist beyond the intoxication state. In the long-term, these impairments seem particularly likely to manifest and may also persist following abstinence if regular and heavy use of cannabis strains high in Δ9-THC is started at an early age. Although still at an early stage, studies that employed advanced neuroimaging techniques have started to model the neural underpinnings of the effects of cannabis use and implicate a network of functional and morphological alterations that may moderate the effects of cannabis on memory function. Future experimental and epidemiological studies that take into consideration individual differences, particularly previous cannabis history and demographic characteristics, but also the precise mixture of the ingredients of the consumed cannabis are necessary to clarify the magnitude and the mechanisms by which cannabis-induced memory impairments occur and to elucidate underlying neurobiological mechanisms. PMID:24648785

  16. Altered functional connectivity during spatial working memory in children with heavy prenatal alcohol exposure.

    Science.gov (United States)

    Infante, M Alejandra; Moore, Eileen M; Bischoff-Grethe, Amanda; Tapert, Susan F; Mattson, Sarah N; Riley, Edward P

    2017-11-01

    Individuals prenatally exposed to alcohol often have impaired spatial working memory (SWM). This study examines functional connections of frontal and parietal regions that support SWM in children with and without prenatal alcohol exposure. Children ages 10 to 16 with histories of heavy prenatal alcohol exposure (AE group; n = 18) and controls (CON group; n = 19) underwent functional magnetic resonance imaging (fMRI) while performing a SWM task. Whole brain task-related functional connectivity of bilateral dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex (PPC) seed regions were estimated for each participant using a psychophysiological interaction approach. Children in the AE group were less accurate than children in the CON group when performing the SWM task (p = 0.008). Positive coupling between bilateral DLPFC seeds and regions within the fronto-parietal network was observed in the CON group, whereas the AE group showed negative connectivity. In contrast to the CON group, the AE group showed positive connectivity between PPC seeds and frontal lobe regions. Across seeds, decreased negative coupling with regions outside the fronto-parietal network (e.g., left middle occipital gyrus) were observed in the AE group relative to the CON group. Functional data clusters were considered significant at p alcohol exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Dynamic functional reorganizations and relationship with working memory performance in healthy aging.

    Directory of Open Access Journals (Sweden)

    Roser eSala-Llonch

    2012-06-01

    Full Text Available In recent years, several theories have been proposed in attempts to identify the neural mechanisms underlying successful cognitive aging. Old subjects show increased neural activity during the performance of tasks, mainly in prefrontal areas, which is interpreted as a compensatory mechanism linked to functional brain efficiency. Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks. We used functional MRI during resting-state and a verbal n-back task with different levels of memory load in a cohort of young and old healthy adults to identify patterns of networks associated with working memory and brain default mode. We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks. Moreover, elders who were able to activate additional areas and to recruit a more bilateral frontal pattern within the task-related network achieved successful performance on the task. We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging. This observation allows the integration of several theories that have been proposed to date regarding the aging brain.

  18. Parietal structure and function explain human variation in working memory biases of visual attention.

    Science.gov (United States)

    Soto, David; Rotshtein, Pia; Kanai, Ryota

    2014-04-01

    Recent research indicates that human attention appears inadvertently biased by items that match the contents of working memory (WM). WM-biases can lead to attentional costs when the memory content matches goal-irrelevant items and to attentional benefits when it matches the sought target. Here we used functional and structural MRI data to determine the neural basis of human variation in WM biases. We asked whether human variation in WM-benefits and WM-costs merely reflects the process of attentional capture by the contents of WM or whether variation in WM biases may be associated with distinct forms of cognitive control over internal WM signals based on selection goals. Human ability to use WM contents to facilitate selection was positively correlated with gray matter volume in the left superior posterior parietal cortex (PPC), while the ability to overcome interference by WM-matching distracters was associated with the left inferior PPC in the anterior IPS. Functional activity in the left PPC, measured by functional MRI, also predicted the magnitude of WM-costs on selection. Both structure and function of left PPC mediate the expression of WM biases in human visual attention. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. The Impact of Working in a Green Certified Building on Cognitive Function and Health.

    Science.gov (United States)

    MacNaughton, Piers; Satish, Usha; Laurent, Jose Guillermo Cedeno; Flanigan, Skye; Vallarino, Jose; Coull, Brent; Spengler, John D; Allen, Joseph G

    2017-03-01

    Thirty years of public health research have demonstrated that improved indoor environmental quality is associated with better health outcomes. Recent research has demonstrated an impact of the indoor environment on cognitive function. We recruited 109 participants from 10 high-performing buildings (i.e. buildings surpassing the ASHRAE Standard 62.1-2010 ventilation requirement and with low total volatile organic compound concentrations) in five U.S. cities. In each city, buildings were matched by week of assessment, tenant, type of worker and work functions. A key distinction between the matched buildings was whether they had achieved green certification. Workers were administered a cognitive function test of higher order decision-making performance twice during the same week while indoor environmental quality parameters were monitored. Workers in green certified buildings scored 26.4% (95% CI: [12.8%, 39.7%]) higher on cognitive function tests, controlling for annual earnings, job category and level of schooling, and had 30% fewer sick building symptoms than those in non-certified buildings. These outcomes may be partially explained by IEQ factors, including thermal conditions and lighting, but the findings suggest that the benefits of green certification standards go beyond measureable IEQ factors. We describe a holistic "buildingomics" approach for examining the complexity of factors in a building that influence human health.

  20. The Effect Of Working Environment Compensation And Working Ethos Towards Employee Performance On Mariso Districts Office In Makassar

    Directory of Open Access Journals (Sweden)

    Rismawati

    2015-08-01

    Full Text Available The influence of the working environment Compensation and Employee Performance Against Work Ethics In Makassar Mariso District Office. The purpose of this study was to determine the effect of the work environment Compensation and Employee Performance Against Working Ethos In Makassar Mariso District Office. The population in this study is Mariso District Office employee In Makassar with a sample size of 70 people. Methods of data collection in this study is a questionnaire interview and documentation. Methods of data analysis using descriptive and quantitative methods namely the multiple linear regression analysis were used to measure the Effect of Work environment Working Ethos Against Compensation and Employee Performance In Makassar Mariso District Office. Based on the F test of independent variables Work Environment Compensation and Working Ethos jointly have the positive and significant effect on the dependent variable employee performance. Through testing the correlation coefficient R was obtained that the degree of correlation or relationship between Work Environment Working Ethos Against Compensation and employee performance is a high correlation is 77.0. And work ethic is the most dominant factor affecting Employee Performance In Makassar Mariso District Office.

  1. Family matters at work : Depleting and enriching effects of employees' family lives on work outcomes

    NARCIS (Netherlands)

    ten Brummelhuis, L.L.

    2009-01-01

    Juggling work and family life has become a daily topic of conversation. As more women enter the workforce and as men increasingly take on household chores and childcare duties, it has become more likely that employees are combining work and a considerable number of family responsibilities. The

  2. INDIVIDUAL DIFFERENCES IN WORKING MEMORY PERFORMANCE: «OVERLOAD» EFFECT

    Directory of Open Access Journals (Sweden)

    Yuri G. Pavlov

    2015-01-01

    Full Text Available The aim of this research is to study the relationship betweenfrontal midline theta rhythm changes and individual differences in working memory performance.Methods. The methods involve behavioural testing on the basis of the program for a presentation of stimulus and registration of answers «PsyTask»; method of EEG (electroencephalography; a technique of measurement of efficiency of working memory; the comparative analysis. Software packages EEGLab for Matlab and Fieldtrip are applied while data processing.Results. After the behavioral test all subjects were separated into 2 groups according to their performance: with «highly productive» and «low productive» memory. Specially prepared author’s complete set of the tasks which complexity varied from average to ultrahigh level was offered to participants of experiment –students and employees of the Ural Federal University and Ural Legal Institute of the Ministry of Internal Affairs. Working memory tasks included sets of verbal stimuli for memorizing in strict order without any mental manipulation and sets of similar stimuli for memorizing in alphabetical order (with manipulations. Measured characteristics of theta-rhythm of EEG during information deduction in memory were compared of two groups’ representatives. The obtained data has shown rather uniform and similar dynamics of decrease in quantity of right answers in process of increasing tasks’ complexity. However, changes of a thetarhythm in different groups had sharply expressed distinctions. «Highly productive» examinees have systematic expansion of a theta-rhythm in the central assignments with stabilisation on the most difficult tasks; «low productive» – while tasks performance of average complexity, a sharp falling of theta-rhythm activity is observed after achievement of its maximum activation.Scientific novelty. The working memory «overload» effect and its EEG correlates are demonstrated on a big sample of

  3. Economic and demographic effects on working women in Latin America.

    Science.gov (United States)

    Psaharopoulos, G; Tzannatos, Z

    1993-01-01

    This analysis of women's work conditions in Latin America includes a description of general trends in female labor force participation in 15 Latin American countries based on census data between 1950 and 1990. Also examined are pay differentials by gender and whether gender alone or individual characteristics of women workers accounted for the sex-wage gap. More extensive treatment is available in the author's other 1992 publications. Trends indicate that marriage and children were important factors determining whether women were in the labor force or not. The probability of being in the labor force was reduced by 50% for married women, and each child reduced the probability by 5%. When marriage and children were controlled for, age had a positive effect on probability of participation. Urban female heads of household had a positive effect on women's labor force participation. The higher a woman's educational qualification, the greater the probability of being in the work force. Earnings increased with increased educational level. An increase of 1 year of schooling for women contributed to an increase in female earnings of 13.1. Investment in education for women has a higher yield for women than for men. Policies that directly or indirectly improve women's employment opportunities, particularly when families are being formed, can have wide distributional effects. Also unresolved was an explanation for why female participation increased during periods of recession and why women are rewarded more for educational effort than men. The suggestion was that public sector employment, which included many women in the labor force, is distorting results.

  4. How Do Organizational Policies and Practices Affect Return to Work and Work Role Functioning Following a Musculoskeletal Injury?

    NARCIS (Netherlands)

    Amick, Benjamin C; Lee, Hyunmi; Hogg-Johnson, Sheilah; Katz, Jeffrey N; Brouwer, Sandra; Franche, Renée-Louise; Bültmann, Ute

    Purpose Organizational-level policies and practices that promote safety leadership and practices, disability management and ergonomic policies and practices are considered key contextual determinants of return to work. Our objective was to examine the role of worker-reported organizational policies

  5. Comorbidities in Spondyloarthritis associate with poor function, work disability and quality of life: Results from the ASAS-COMOSPA study.

    Science.gov (United States)

    Nikiphorou, E; Ramiro, S; van der Heijde, D; Norton, S; Moltó, A; Dougados, M; van den Bosch, F; Landewé, R

    2017-11-10

    Comorbidities add to the burden of disease and its complexity, and may prevent the achievement of treat-to-target goals. The objective of this study was to study the relationship between comorbidities and key disease outcomes in Spondyloarthritis, namely function, work ability and quality of life. Patients from the multi-national (22 countries), cross-sectional ASAS-COMOSPA study were included in the analysis provided they fulfilled the ASAS criteria. Data on comorbidities based on both self- and physician-report were collected through questionnaires and were subsequently used to compute the Rheumatic Disease Comorbidity Index (RDCI). Univariable and multivariable (adjusted for relevant confounders) multilevel (with country as a random effect) linear or logistic (as appropriate) regression analyses were conducted to investigate the relationship between the RDCI and: (1) functional ability; (2) work ability; (3) quality of life. In total, 3370 of 3984 (85%) patients recruited fulfilled the ASAS criteria: 66% were male, mean (SD) age was 43 (14) years, mean (SD) disease duration was 8.4 (9.5) years and mean (SD) RDCI was 0.7 (1.1). At least one comorbidity was reported in 51% of patients; 9% had ≥3 comorbidities. RDCI was independently associated with higher BASFI (β=0.37;95%CI [0.30,0.43]); lower EuroQol five dimensions questionnaire (EQ5D:β=-0.03; [-0.04,-0.02]); less work employment (OR=0.83; [0.76,0.91]); higher absenteeism (β=1.18; [1.04,1.34]) and higher presenteeism (β=1.42; [1.26,1.61]). Comorbidities in SpA adversely influence physical function, work ability and quality of life and are important to take into account in daily clinical practice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. Effectiveness of a return-to-work intervention for subacute low-back pain: a systematic review

    NARCIS (Netherlands)

    Hlobil, H.; Staal, J.B.; Spoelstra, M.; Ari�ns, G.A.; Smid, T.; van Mechelen, W.

    2005-01-01

    The effectiveness of return-to-work intervention for subacute low-back pain on work absenteeism, pain severity, and functional status was examined by means of a systematic review of randomized controlled trials. Publications in English that met the selection criteria were identified in a

  7. The circadian regulation of sleep: impact of a functional ADA-polymorphism and its association to working memory improvements.

    Science.gov (United States)

    Reichert, Carolin F; Maire, Micheline; Gabel, Virginie; Hofstetter, Marcel; Viola, Antoine U; Kolodyazhniy, Vitaliy; Strobel, Werner; Goetz, Thomas; Bachmann, Valérie; Landolt, Hans-Peter; Cajochen, Christian; Schmidt, Christina

    2014-01-01

    Sleep is regulated in a time-of-day dependent manner and profits working memory. However, the impact of the circadian timing system as well as contributions of specific sleep properties to this beneficial effect remains largely unexplored. Moreover, it is unclear to which extent inter-individual differences in sleep-wake regulation depend on circadian phase and modulate the association between sleep and working memory. Here, sleep electroencephalography (EEG) was recorded during a 40-h multiple nap protocol, and working memory performance was assessed by the n-back task 10 times before and after each scheduled nap sleep episode. Twenty-four participants were genotyped regarding a functional polymorphism in adenosine deaminase (rs73598374, 12 G/A-, 12 G/G-allele carriers), previously associated with differences in sleep-wake regulation. Our results indicate that genotype-driven differences in sleep depend on circadian phase: heterozygous participants were awake longer and slept less at the end of the biological day, while they exhibited longer non rapid eye movement (NREM) sleep and slow wave sleep concomitant with reduced power between 8-16 Hz at the end of the biological night. Slow wave sleep and NREM sleep delta EEG activity covaried positively with overall working memory performance, independent of circadian phase and genotype. Moreover, REM sleep duration benefitted working memory particularly when occurring in the early morning hours and specifically in heterozygous individuals. Even though based on a small sample size and thus requiring replication, our results suggest genotype-dependent differences in circadian sleep regulation. They further indicate that REM sleep, being under strong circadian control, boosts working memory performance according to genotype in a time-of-day dependent manner. Finally, our data provide first evidence that slow wave sleep and NREM sleep delta activity, majorly regulated by sleep homeostatic mechanisms, is linked to working

  8. The circadian regulation of sleep: impact of a functional ADA-polymorphism and its association to working memory improvements.

    Directory of Open Access Journals (Sweden)

    Carolin F Reichert

    Full Text Available Sleep is regulated in a time-of-day dependent manner and profits working memory. However, the impact of the circadian timing system as well as contributions of specific sleep properties to this beneficial effect remains largely unexplored. Moreover, it is unclear to which extent inter-individual differences in sleep-wake regulation depend on circadian phase and modulate the association between sleep and working memory. Here, sleep electroencephalography (EEG was recorded during a 40-h multiple nap protocol, and working memory performance was assessed by the n-back task 10 times before and after each scheduled nap sleep episode. Twenty-four participants were genotyped regarding a functional polymorphism in adenosine deaminase (rs73598374, 12 G/A-, 12 G/G-allele carriers, previously associated with differences in sleep-wake regulation. Our results indicate that genotype-driven differences in sleep depend on circadian phase: heterozygous participants were awake longer and slept less at the end of the biological day, while they exhibited longer non rapid eye movement (NREM sleep and slow wave sleep concomitant with reduced power between 8-16 Hz at the end of the biological night. Slow wave sleep and NREM sleep delta EEG activity covaried positively with overall working memory performance, independent of circadian phase and genotype. Moreover, REM sleep duration benefitted working memory particularly when occurring in the early morning hours and specifically in heterozygous individuals. Even though based on a small sample size and thus requiring replication, our results suggest genotype-dependent differences in circadian sleep regulation. They further indicate that REM sleep, being under strong circadian control, boosts working memory performance according to genotype in a time-of-day dependent manner. Finally, our data provide first evidence that slow wave sleep and NREM sleep delta activity, majorly regulated by sleep homeostatic mechanisms, is

  9. The Effect of Cold Work on Properties of Alloy 617

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-01

    Alloy 617 is approved for non-nuclear construction in the ASME Boiler and Pressure Vessel Code Section I and Section VIII, but is not currently qualified for nuclear use in ASME Code Section III. A draft Code Case was submitted in 1992 to qualify the alloy for nuclear service but efforts were stopped before the approval process was completed.1 Renewed interest in high temperature nuclear reactors has resulted in a new effort to qualify Alloy 617 for use in nuclear pressure vessels. The mechanical and physical properties of Alloy 617 were extensively characterized for the VHTR programs in the 1980’s and incorporated into the 1992 draft Code Case. Recently, the properties of modern heats of the alloy that incorporate an additional processing step, electro-slag re-melting, have been characterized both to confirm that the properties of contemporary material are consistent with those in the historical record and to increase the available database. A number of potential issues that were identified as requiring further consideration prior to the withdrawal of the 1992 Code Case are also being re-examined in the current R&D program. Code Cases are again being developed to allow use of Alloy 617 for nuclear design within the rules of the ASME Boiler and Pressure Vessel Code. In general the Code defines two temperature ranges for nuclear design with austenitic and nickel based alloys. Below 427°C (800°F) time dependent behavior is not considered, while above this temperature creep and creep-fatigue are considered to be the dominant life-limiting deformation modes. There is a corresponding differentiation in the treatment of the potential for effects associated with cold work. Below 427°C the principal issue is the relationship between the level of cold work and the propensity for stress corrosion cracking and above that temperature the primary concern is the impact of cold work on creep-rupture behavior.

  10. Electronic structures of 1-ML C84/Ag(111): Energy level alignment and work function variation

    Science.gov (United States)

    Wang, Peng; Zhao, Li-Li; Zhang, Jin-Juan; Li, Wen-Jie; Liu, Wei-Hui; Chen, Da; Sheng, Chun-Qi; Wang, Jia-Ou; Qian, Hai-Jie; Ibrahim, Kurash; Li, Hong-Nian

    2017-12-01

    The electronic structures of fullerene/metal interface are critical to the performance of devices based on fullerene in molecular electronics and organic electronics. Herein, we investigate the electronic structures at the interface between C84 and Ag(111) by photoelectron spectroscopy and soft X-ray absorption spectroscopy techniques. It is observed that C84 monolayer on Ag(111) surface (1-ML C84/Ag(111)) has metallic nature. A charge transfer from substrate to the unoccupied states of C84 is determined to be 1.3 electrons per molecule. However, the work function of 1-ML C84 (4.72 eV) is observed slightly larger than that of the clean Ag(111) substrate (4.50 eV). A bidirectional charge transfer model is introduced to understand the work function variation of the fullerene/metal system. In addition to the charge transfer from substrate to the adsorbate's unoccupied states, there exists non-negligible back charge transfer from fullerene occupied molecular orbital to the metal substrate through interfacial hybridization. The Fermi level will be pinned at ∼4.72 eV for C84 monolayer on coinage metal substrate.

  11. Modulation of working memory function by motivation through loss-aversion.

    Science.gov (United States)

    Krawczyk, Daniel C; D'Esposito, Mark

    2013-04-01

    Cognitive performance is affected by motivation. Few studies, however, have investigated the neural mechanisms of the influence of motivation through potential monetary punishment on working memory. We employed functional MRI during a delayed recognition task that manipulated top-down control demands with added monetary incentives to some trials in the form of potential losses of bonus money. Behavioral performance on the task was influenced by loss-threatening incentives in the form of faster and more accurate performance. As shown previously, we found enhancement of activity for relevant stimuli occurs throughout all task periods (e.g., stimulus encoding, maintenance, and response) in both prefrontal and visual association cortex. Further, these activation patterns were enhanced for trials with possible monetary loss relative to nonincentive trials. During the incentive cue, the amygdala and striatum showed significantly greater activation when money was at a possible loss on the trial. We also evaluated patterns of functional connectivity between regions responsive to monetary consequences and prefrontal areas responsive to the task. This analysis revealed greater delay period connectivity between and the left insula and prefrontal cortex with possible monetary loss relative to nonincentive trials. Overall, these results reveal that incentive motivation can modulate performance on working memory tasks through top-down signals via amplification of activity within prefrontal and visual association regions selective to processing the perceptual inputs of the stimuli to be remembered. Copyright © 2011 Wiley Periodicals, Inc.

  12. The effects of intrapersonal, intragroup, and intergroup conflict on team performance effectiveness and work satisfaction.

    Science.gov (United States)

    Cox, Kathleen B

    2003-01-01

    Although numerous studies have focused on conflict management, few have considered the effects of unit technology and intrapersonal, intragroup, and intergroup conflict on team performance effectiveness and work satisfaction. The model was tested using a nonexperimental design. Path analysis using multiple regression was used to test the model. The nonrandom sample consisted of 141 nurses employed on 13 inpatient units at a state-supported, 597-bed academic medical center in a southeastern city. Findings indicated that intrapersonal conflict had a direct negative impact on intragroup conflict and work satisfaction. Intragroup conflict had direct negative effects on work satisfaction and team performance effectiveness. Unit technology had a direct negative impact on work satisfaction. Findings have implications for administrators to implement strategies to decrease a stressful work environment and increase team-building activities.

  13. Eating and shift work - effects on habits, metabolism and performance.

    Science.gov (United States)

    Lowden, Arne; Moreno, Claudia; Holmbäck, Ulf; Lennernäs, Maria; Tucker, Philip

    2010-03-01

    Compared to individuals who work during the day, shift workers are at higher risk of a range of metabolic disorders and diseases (eg, obesity, cardiovascular disease, peptic ulcers, gastrointestinal problems, failure to control blood sugar levels, and metabolic syndrome). At least some of these complaints may be linked to the quality of the diet and irregular timing of eating, however other factors that affect metabolism are likely to play a part, including psychosocial stress, disrupted circadian rhythms, sleep debt, physical inactivity, and insufficient time for rest and revitalization. In this overview, we examine studies on food and nutrition among shift workers [ie, dietary assessment (designs, methods, variables) and the factors that might influence eating habits and metabolic parameters]. The discussion focuses on the quality of existing dietary assessment data, nutritional status parameters (particularly in obesity), the effect of circadian disruptions, and the possible implications for performance at work. We conclude with some dietary guidelines as a basis for managing the nutrition of shift workers.

  14. Working memory training in children: Effectiveness depends on temperament.

    Science.gov (United States)

    Studer-Luethi, Barbara; Bauer, Catherine; Perrig, Walter J

    2016-02-01

    Studies revealing transfer effects of working memory (WM) training on non-trained cognitive performance of children hold promising implications for scholastic learning. However, the results of existing training studies are not consistent and provoke debates about the potential and limitations of cognitive enhancement. To examine the influence of individual differences on training outcomes is a promising approach for finding causes for such inconsistencies. In this study, we implemented WM training in an elementary school setting. The aim was to investigate near and far transfer effects on cognitive abilities and academic achievement and to examine the moderating effects of a dispositional and a regulative temperament factor, neuroticism and effortful control. Ninety-nine second-graders were randomly assigned to 20 sessions of computer-based adaptive WM training, computer-based reading training, or a no-contact control group. For the WM training group, our analyses reveal near transfer on a visual WM task, far transfer on a vocabulary task as a proxy for crystallized intelligence, and increased academic achievement in reading and math by trend. Considering individual differences in temperament, we found that effortful control predicts larger training mean and gain scores and that there is a moderation effect of both temperament factors on post-training improvement: WM training condition predicted higher post-training gains compared to both control conditions only in children with high effortful control or low neuroticism. Our results suggest that a short but intensive WM training program can enhance cognitive abilities in children, but that sufficient self-regulative abilities and emotional stability are necessary for WM training to be effective.

  15. Effects of proactive interference on non-verbal working memory.

    Science.gov (United States)

    Cyr, Marilyn; Nee, Derek E; Nelson, Eric; Senger, Thea; Jonides, John; Malapani, Chara

    2017-02-01

    Working memory (WM) is a cognitive system responsible for actively maintaining and processing relevant information and is central to successful cognition. A process critical to WM is the resolution of proactive interference (PI), which involves suppressing memory intrusions from prior memories that are no longer relevant. Most studies that have examined resistance to PI in a process-pure fashion used verbal material. By contrast, studies using non-verbal material are scarce, and it remains unclear whether the effect of PI is domain-general or whether it applies solely to the verbal domain. The aim of the present study was to examine the effect of PI in visual WM using both objects with high and low nameability. Using a Directed-Forgetting paradigm, we varied discriminability between WM items on two dimensions, one verbal (high-nameability vs. low-nameability objects) and one perceptual (colored vs. gray objects). As in previous studies using verbal material, effects of PI were found with object stimuli, even after controlling for verbal labels being used (i.e., low-nameability condition). We also found that the addition of distinctive features (color, verbal label) increased performance in rejecting intrusion probes, most likely through an increase in discriminability between content-context bindings in WM.

  16. Dependence of the electron work function change of the rhodium (100) face on the order of oxygen and hydrogen adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Kalish, T.V.; Belyaeva, M.E.

    1988-03-01

    It has been shown that the order of hydrogen and oxygen adsorption on rhodium determines the course of the adsorbates interaction. Changes in electron work function of the rhodium (100) face which occur as a function of time during hydrogen adsorption on a surface with preadsorbed oxygen was studied along with changes in the electron work function during adsorption of hydrogen and oxygen. The electron work function was determined by photoelectric emission. Gas adsorption occurred at room temperature, the gas phase composition was determined with an omegatron, and Auger spectroscopy was used to check the cleanliness of the original surface.

  17. Effectiveness of work skills programmes for offenders with mental disorders: A systematic review.

    Science.gov (United States)

    Talbot, Emily C; Völlm, Birgit; Khalifa, Najat

    2017-02-01

    Academic literature and government initiatives have emphasised the importance of work as a means of improving health and reducing reoffending among offenders with mental disorders. Whilst a number of work skills programmes have shown promise for offenders more generally, evaluation of evidence for their effectiveness for those with a mental disorder is lacking, particularly in relation to improving employment outcomes. To assess the evidence on the effectiveness of work skills programmes for mentally disordered offenders. A systematic review of the literature was conducted by searching the following databases: PsycINFO, CINAHL, Cochrane Library (Trials Register), Embase and Medline, using search terms which included Work Skills Programme*, Offend* and Mental*. Any empirical comparison study of work skills programmes was included in this review. The primary outcome was employment. Secondary outcomes included employment outcomes, reoffending, education, mental state, substance misuse, global functioning, quality of life, acceptability, leaving the study early and cost effectiveness or other economic outcomes. Six articles met the inclusion criteria. Collectively they provided limited evidence that work skills programmes increase the likelihood of people with mental disorder who are offenders obtaining employment in the short term, but there are insufficient studies to determine the long-term impact of work skills programmes. There is modest evidence to support inclusion of specific work skills programmes in the treatment of offenders with mental disorder. Future studies should be of theoretically driven programmes, such as Individual Placement Support (IPS), and use a standard set of relevant outcome measures and long enough follow-up for testing the effectiveness of any programme on engagement in competitive, paid employment as, even if skilled, offenders with mental disorder must constitute a hard to place group. Copyright © 2015 John Wiley & Sons, Ltd. Copyright

  18. Working memory-related functional brain patterns in never medicated children with ADHD.

    Directory of Open Access Journals (Sweden)

    Isabelle Massat

    Full Text Available Attention Deficit/Hyperactivity Disorder (ADHD is a pervasive neurodevelopmental disorder characterized by 3 clusters of age-inappropriate cardinal symptoms: inattention, hyperactivity and impulsivity. These clinical/behavioural symptoms are assumed to result from disturbances within brain systems supporting executive functions including working memory (WM, which refers to the ability to transiently store and flexibly manipulate task-relevant information. Ongoing or past medications, co-morbidity and differences in task performance are potential, independent confounds in assessing the integrity of cerebral patterns in ADHD. In the present study, we recorded WM-related cerebral activity during a memory updating N-back task using functional Magnetic Resonance Imaging (fMRI in control children and never medicated, prepubescent children with ADHD but without comorbid symptoms. Despite similar updating performance than controls, children with ADHD exhibited decreased, below baseline WM-related activation levels in a widespread cortico-subcortical network encompassing bilateral occipital and inferior parietal areas, caudate nucleus, cerebellum and functionally connected brainstem nuclei. Distinctive functional connectivity patterns were also found in the ADHD in these regions, with a tighter coupling in the updating than in the control condition with a distributed WM-related cerebral network. Especially, cerebellum showed tighter coupling with activity in an area compatible with the brainstem red nucleus. These results in children with clinical core symptoms of ADHD but without comorbid affections and never treated with medication yield evidence for a core functional neuroanatomical network subtending WM-related processes in ADHD, which may participate to the pathophysiology and expression of clinical symptoms.

  19. Task-independent and task-specific age effects on brain activity during working memory, visual attention and episodic retrieval

    NARCIS (Netherlands)

    Cabeza, R.; Daselaar, S.M.; Dolcos, F.; Prince, S.E.; Budde, M.; Nyberg, L.

    2004-01-01

    t is controversial whether the effects of aging on various cognitive functions have the same common cause or several different causes. To investigate this issue, we scanned younger and older adults with functional magnetic resonance imaging (fMRI) while performing three different tasks: working

  20. [The Prognostic Validity of the Functional Capacity Evaluation ELA in Work-Related Medical Rehabilitation].

    Science.gov (United States)

    Bühne, David; Alles, Torsten; Hetzel, Christian; Froböse, Ingo

    2017-05-04

    The aim of the study was to determine the ability of FCE (Functional Capacity Evaluation) to predict sustained return-to-work (RTW). A multicentric prospective cohort study was conducted in cooperation with 4 outpatient rehabilitation clinics. The sample consisted of 198 patients. Sustained RTW was defined as a combination of employment at 3-month follow-up with a low level of sick leave (dependent variable 1) resp. with a moderate or better rating of the current work ability with respect to the physical demands at work (dependent variable 2). Based on questionnaires and FCE information, logistic regression models were calculated to predict sustained RTW. The FCE-information at discharge predicted sustained RTW after adjusting for assessors (Odds Ratio - OR=17.2 [95% CI: 6.2-57.8] resp. OR 12.8 [95% CI: 5.1-32.1]) as well as after adjusting for additional RTW predictors (OR 14.6 [95% CI: 4.8-44.9] resp. OR 10.1 [95% CI: 3.5-29.4]). Concerning dependent variable 1 and the FCE-information at admission there was a gain of information towards a model based on patient self-reports (OR 2.6 [95% CI: 1.1-6.0]). The study supports the predictive validity of crude and adjusted FCE-information. The gain of information towards patient self-reports is unclear. © Georg Thieme Verlag KG Stuttgart · New York.

  1. On the relationship between executive functions of working memory and components derived from fluid intelligence measures.

    Science.gov (United States)

    Ren, Xuezhu; Schweizer, Karl; Wang, Tengfei; Chu, Pei; Gong, Qin

    2017-10-01

    The aim of the current study is to provide new insights into the relationship between executive functions and intelligence measures in considering the item-position effect observed in intelligence items. Raven's Advanced Progressive Matrices (APM) and Horn's LPS reasoning test were used to assess fluid intelligence which served as criterion in investigating the relationship between intelligence and executive functions. A battery of six experimental tasks measured the updating, shifting, and inhibition processes of executive functions. Data were collected from 205 university students. Fluid intelligence showed substantial correlations with the updating and inhibition processes and no correlation with the shifting process without considering the item-position effect. Next, the fixed-link model was applied to APM and LPS data separately to decompose them into an ability component and an item-position component. The results of relating the components to executive functions showed that the updating and shifting processes mainly contributed to the item-position component whereas the inhibition process was mainly associated with the ability component of each fluid intelligence test. These findings suggest that improvements in the efficiency of updating and shifting processes are likely to occur during the course of completing intelligence measures and inhibition is important for intelligence in general. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Three functional aspects of working memory as strong predictors of early school achievements: The review and illustrative evidence

    Directory of Open Access Journals (Sweden)

    Sedek Grzegorz

    2016-04-01

    Full Text Available The paper presents an overview of research on working memory as a predictor of early school achievements. We contrast two main areas of research on the role of working memory in school achievements: the first concerns the structural model of working memory and the second focuses on executive functions. Then, we discuss the facet model of working memory as a promising approach merging the two research branches on working memory tasks as predictors of early school achievements. At the end we present exemplary results of the research conducted on a national sample of six- and seven-year-olds in Poland, which indicates strong relation of working memory functions with the measures of competences in mathematics, reading, and writing. Additionally, the mediation analyses, with parents’ education as a covariate, indicate that the influence of age on achievements in math, reading, and writing in six- and seven-year olds is mediated by working memory functions.

  3. Effects of methylphenidate on memory functions of adults with ADHD.

    Science.gov (United States)

    Fuermaier, Anselm B M; Tucha, Lara; Koerts, Janneke; Weisbrod, Matthias; Lange, Klaus W; Aschenbrenner, Steffen; Tucha, Oliver

    2017-01-01

    Neuropsychological research on adults with attention deficit hyperactivity disorder (ADHD) revealed considerable impairments in memory functions related to executive control. However, only limited evidence exists supporting the effects of pharmacological treatment using methylphenidate (MPH) on memory functions. The aim of the present study was, therefore, to explore the impact of MPH on various memory functions of adults with ADHD. Thirty-one adults with ADHD treated with MPH, 36 adults with ADHD not-treated with MPH, and 36 healthy individuals were assessed on several aspects of memory, including short-term memory, working memory, retrospective memory, prospective memory, and source memory. Multivariate statistical analyses were applied to compare memory functions between groups. Nonmedicated adults with ADHD showed considerable impairments in memory functions related to executive control. Adults with ADHD treated with MPH showed improved memory functions when compared to nonmedicated patients, but were still impaired when compared to healthy controls. The present study emphasized the severity of memory impairments of adults with ADHD. A pharmacological treatment with MPH appeared to improve memory, but does not normalize functioning. Additional treatment intervention (e.g., cognitive-behavioral therapy) is therefore necessary.

  4. Effects of childhood trauma on working memory in affective and non-affective psychotic disorders.

    Science.gov (United States)

    Quidé, Yann; O'Reilly, Nicole; Rowland, Jesseca E; Carr, Vaughan J; Elzinga, Bernet M; Green, Melissa J

    2017-06-01

    Childhood trauma is a significant risk factor for the development of psychotic disorders, and may influence executive brain functions. We thus set out to investigate the long-term effects of childhood trauma exposure on brain function of adult chronic patients diagnosed with schizophrenia, schizoaffective disorder and (psychotic) bipolar-I disorder while performing a standard 2/0-back working memory task. Participants were 50 cases diagnosed with schizophrenia/schizoaffective disorder (SCZ), 42 cases with bipolar-I disorder (BD), and 47 healthy controls (HC). Among this sample, 56 clinical cases (SCZ = 32; BD = 24) and 17 HC reported significant levels of childhood trauma, while 36 clinical cases (SCZ = 18; BD = 18) and 30 HC did not. Effects of childhood trauma on working memory-related brain activation were examined in combined samples of clinical cases (independently of diagnosis) relative to HCs, as well as within each diagnostic category. Case-control analyses revealed increased activation of the left inferior parietal lobule as a main effect of trauma exposure. In addition, trauma exposure interacted with a diagnosis of SCZ or BD to reveal trauma-related increased activation in the cuneus in clinical cases and decreased activation in this region in controls. Disorder-specific functional alterations were also evident in the SCZ sample, but not BD. Childhood trauma exposure elicits aberrant function of parietal regions involved in working memory performance regardless of clinical status, as well as task-relevant visual regions that participates to attentional processes. Childhood trauma may therefore contribute to alterations in attention in SCZ and BD while performing an n-back working memory task.

  5. Acute aerobic exercise increases cortical activity during working memory: a functional MRI study in female college students.

    Science.gov (United States)

    Li, Lin; Men, Wei-Wei; Chang, Yu-Kai; Fan, Ming-Xia; Ji, Liu; Wei, Gao-Xia

    2014-01-01

    There is increasing evidence that acute aerobic exercise is associated with improved cognitive function. However, neural correlates of its cognitive plasticity remain largely unknown. The present study examined the effect of a session of acute aerobic exercise on working memory task-evoked brain activity as well as task performance. A within-subjects design with a counterbalanced order was employed. Fifteen young female participants (M = 19.56, SD = 0.81) were scanned using functional magnetic resonance imaging while performing a working memory task, the N-back task, both following an acute exercise session with 20 minutes of moderate intensity and a control rest session. Although an acute session of exercise did not improve behavioral performance, we observed that it had a significant impact on brain activity during the 2-back condition of the N-back task. Specifically, acute exercise induced increased brain activation in the right middle prefrontal gyrus, the right lingual gyrus, and the left fusiform gyrus as well as deactivations in the anterior cingulate cortexes, the left inferior frontal gyrus, and the right paracentral lobule. Despite the lack of an effect on behavioral measures, significant changes after acute exercise with activation of the prefrontal and occipital cortexes and deactivation of the anterior cingulate cortexes and left frontal hemisphere reflect the improvement of executive control processes, indicating that acute exercise could benefit working memory at a macro-neural level. In addition to its effects on reversing recent obesity and disease trends, our results provide substantial evidence highlighting the importance of promoting physical activity across the lifespan to prevent or reverse cognitive and neural decline.

  6. Effects of concomitant methylphenidate and ethanol administration on working and reference memory in rats.

    Science.gov (United States)

    Sloan, Anthony R; McGovern, Robin; Buffalari, Deanne M

    Recent studies have suggested that college students are heavily engaged in non-medical use of stimulant drugs prescribed to treat attention deficit hyperactivity disorder. This age group is also at high risk for alcohol use. Despite their potential co-abuse, little work has examined how these drugs interact to affect cognitive abilities. In fact, these drugs have opposing effects on working memory, which brings into question how they may interact to affect this particular behavior. The purpose of this research was to examine the concomitant effects of methylphenidate (MPH) and ethanol (EtOH) on working and reference memory. Rats were first trained on the radial arm maze task to establish a baseline performance rate measured as average number of reference and working memory errors. Performance was then assessed after injections of saline, MPH alone, EtOH alone, and MPH+EtOH combined. While both doses of MPH caused nonsignificant improvements in working memory, when combined with EtOH, there was an overall impairment in working and reference memory compared to other conditions. EtOH alone also decreased memory. These data indicate increased impairment of memory function with combined MPH and EtOH use. By understanding how the combination of methylphenidate and alcohol affects memory, we can better assess the risks of taking both substances simultaneously. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. DHA Effects in Brain Development and Function

    Directory of Open Access Journals (Sweden)

    Lotte Lauritzen

    2016-01-01

    Full Text Available Docosahexaenoic acid (DHA is a structural constituent of membranes specifically in the central nervous system. Its accumulation in the fetal brain takes place mainly during the last trimester of pregnancy and continues at very high rates up to the end of the second year of life. Since the endogenous formation of DHA seems to be relatively low, DHA intake may contribute to optimal conditions for brain development. We performed a narrative review on research on the associations between DHA levels and brain development and function throughout the lifespan. Data from cell and animal studies justify the indication of DHA in relation to brain function for neuronal cell growth and differentiation as well as in relation to neuronal signaling. Most data from human studies concern the contribution of DHA to optimal visual acuity development. Accumulating data indicate that DHA may have effects on the brain in infancy, and recent studies indicate that the effect of DHA may depend on gender and genotype of genes involved in the endogenous synthesis of DHA. While DHA levels may affect early development, potential effects are also increasingly recognized during childhood and adult life, suggesting a role of DHA in cognitive decline and in relation to major psychiatric disorders.

  8. Effects of arginine vasopressin on musical working memory.

    Science.gov (United States)

    Granot, Roni Y; Uzefovsky, Florina; Bogopolsky, Helena; Ebstein, Richard P

    2013-01-01

    Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP) and musical working memory (WM). The current study set out to test the influence of intranasal administration (INA) of AVP on musical as compared to verbal WM using a double blind crossover (AVP-placebo) design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo) in a second session, 1 week apart. In each session subjects completed the tonal subtest from Gordon's "Musical Aptitude Profile," the interval subtest from the "Montreal Battery for Evaluation of Amusias (MBEA)," and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV) were higher than for the group receiving vasopressin in the first session (VP) (p music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

  9. Visual Working Memory Load-Related Changes in Neural Activity and Functional Connectivity

    Science.gov (United States)

    Li, Ling; Zhang, Jin-Xiang; Jiang, Tao

    2011-01-01

    Background Visual working memory (VWM) helps us store visual information to prepare for subsequent behavior. The neuronal mechanisms for sustaining coherent visual information and the mechanisms for limited VWM capacity have remained uncharacterized. Although numerous studies have utilized behavioral accuracy, neural activity, and connectivity to explore the mechanism of VWM retention, little is known about the load-related changes in functional connectivity for hemi-field VWM retention. Methodology/Principal Findings In this study, we recorded electroencephalography (EEG) from 14 normal young adults while they performed a bilateral visual field memory task. Subjects had more rapid and accurate responses to the left visual field (LVF) memory condition. The difference in mean amplitude between the ipsilateral and contralateral event-related potential (ERP) at parietal-occipital electrodes in retention interval period was obtained with six different memory loads. Functional connectivity between 128 scalp regions was measured by EEG phase synchronization in the theta- (4–8 Hz), alpha- (8–12 Hz), beta- (12–32 Hz), and gamma- (32–40 Hz) frequency bands. The resulting matrices were converted to graphs, and mean degree, clustering coefficient and shortest path length was computed as a function of memory load. The results showed that brain networks of theta-, alpha-, beta-, and gamma- frequency bands were load-dependent and visual-field dependent. The networks of theta- and alpha- bands phase synchrony were most predominant in retention period for right visual field (RVF) WM than for LVF WM. Furthermore, only for RVF memory condition, brain network density of theta-band during the retention interval were linked to the delay of behavior reaction time, and the topological property of alpha-band network was negative correlation with behavior accuracy. Conclusions/Significance We suggest that the differences in theta- and alpha- bands between LVF and RVF conditions in

  10. Working with low back pain: problem-solving orientation and function.

    Science.gov (United States)

    Shaw, W S; Feuerstein, M; Haufler, A J; Berkowitz, S M; Lopez, M S

    2001-08-01

    A number of ergonomic, workplace and individual psychosocial factors and health behaviors have been associated with the onset, exacerbation and/or maintenance of low back pain (LBP). The functional impact of these factors may be influenced by how a worker approaches problems in general. The present study was conducted to determine whether problem-solving orientation was associated with physical and mental health outcomes in fully employed workers (soldiers) reporting a history of LBP in the past year. The sample consisted of 475 soldiers (446 male, 29 female; mean age 24.5 years) who worked in jobs identified as high risk for LBP-related disability and reported LBP symptoms in the past 12 months. The Social Problem-Solving Inventory and the Standard Form-12 (SF-12) were completed by all subjects. Hierarchical multiple regression analyses were used to predict the SF-12 physical health summary scale from interactions of LBP symptoms with each of five problem-solving subscales. Low scores on positive problem-solving orientation (F(1,457)=4.49), and high scores on impulsivity/carelessness (F(1,457)=9.11) were associated with a steeper gradient in functional loss related to LBP. Among those with a longer history of low-grade LBP, an avoidant approach to problem-solving was also associated with a steeper gradient of functional loss (three-way interaction; F(1,458)=4.58). These results suggest that the prolonged impact of LBP on daily function may be reduced by assisting affected workers to conceptualize LBP as a problem that can be overcome and using strategies that promote taking an active role in reducing risks for LBP. Secondary prevention efforts may be improved by addressing these factors.

  11. Visual working memory load-related changes in neural activity and functional connectivity.

    Directory of Open Access Journals (Sweden)

    Ling Li

    Full Text Available BACKGROUND: Visual working memory (VWM helps us store visual information to prepare for subsequent behavior. The neuronal mechanisms for sustaining coherent visual information and the mechanisms for limited VWM capacity have remained uncharacterized. Although numerous studies have utilized behavioral accuracy, neural activity, and connectivity to explore the mechanism of VWM retention, little is known about the load-related changes in functional connectivity for hemi-field VWM retention. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we recorded electroencephalography (EEG from 14 normal young adults while they performed a bilateral visual field memory task. Subjects had more rapid and accurate responses to the left visual field (LVF memory condition. The difference in mean amplitude between the ipsilateral and contralateral event-related potential (ERP at parietal-occipital electrodes in retention interval period was obtained with six different memory loads. Functional connectivity between 128 scalp regions was measured by EEG phase synchronization in the theta- (4-8 Hz, alpha- (8-12 Hz, beta- (12-32 Hz, and gamma- (32-40 Hz frequency bands. The resulting matrices were converted to graphs, and mean degree, clustering coefficient and shortest path length was computed as a function of memory load. The results showed that brain networks of theta-, alpha-, beta-, and gamma- frequency bands were load-dependent and visual-field dependent. The networks of theta- and alpha- bands phase synchrony were most predominant in retention period for right visual field (RVF WM than for LVF WM. Furthermore, only for RVF memory condition, brain network density of theta-band during the retention interval were linked to the delay of behavior reaction time, and the topological property of alpha-band network was negative correlation with behavior accuracy. CONCLUSIONS/SIGNIFICANCE: We suggest that the differences in theta- and alpha- bands between LVF and RVF

  12. Job insecurity during recessions: effects on survivors? work stress

    OpenAIRE

    Modrek, Sepideh; Cullen, Mark R

    2013-01-01

    Background Previous studies show a variety of negative health consequences for the remaining workforce after downsizing events. This study examined self-reported work stress from 2009?2012 in the context of a large multi-site aluminum manufacturing company that underwent severe downsizing in 2009. Methods This study examined the association between work stress and working at a work site that underwent severe downsizing. We assessed the level of downsizing across thirty plants in 2009 and cate...

  13. Job insecurity during recessions: effects on survivors' work stress.

    Science.gov (United States)

    Modrek, Sepideh; Cullen, Mark R

    2013-10-06

    Previous studies show a variety of negative health consequences for the remaining workforce after downsizing events. This study examined self-reported work stress from 2009-2012 in the context of a large multi-site aluminum manufacturing company that underwent severe downsizing in 2009. This study examined the association between work stress and working at a work site that underwent severe downsizing. We assessed the level of downsizing across thirty plants in 2009 and categorized seven as having undergone severe downsizing. We linked plant-level downsizing information to individual workers' responses to an annual work engagement survey, which included three work stress questions. From 2009 to 2012 over 14, 000 employees were asked about their experience of work stress. Though the surveys were anonymous, the surveys captured employees' demographic and employment characteristic as well as plant location. We used hierarchical logistic regressions to compare responses of workers at severely downsized plants to workers at all other plant while controlling for demographic and plant characteristics. Responses to the work stress questions and one control question were examined. In all yearly surveys salaried workers consistently reported having more work stress than hourly workers. There was no differential in work stress for workers at severely downsized plants in 2009. In 2010 to 2012, salaried workers who remained at severely downsized plants reported significantly higher work stress than salaried workers at all other plants across multiple work stress questions. Examination of the 2006 survey confirmed that there were no pre-existing differences in work stress among salaried employees working at plants that would eventually experience severe downsizing. In addition, there was no difference in responses to the control question at severely downsized plants. Salaried workers at plants with high layoffs experienced more work stress after 2009 than their counterparts at

  14. Role of Transformational Leadership in Effective Organizational Knowledge Creation Practices: Mediating Effects of Employees' Work Engagement

    Science.gov (United States)

    Song, Ji Hoon; Kolb, Judith A.; Lee, Ung Hee; Kim, Hye Kyoung

    2012-01-01

    Engagement as an area of increasing interest has been discussed in terms of a wide array of organizational policies, practices, and outcomes. This study focuses on a specific aspect of work engagement and its relationship with leadership practices and the outcome of knowledge creation. The mediating effect of employees' work engagement level was…

  15. Respiratory Health Effects Associated with Restoration Work in Post-Hurricane Katrina New Orleans

    Directory of Open Access Journals (Sweden)

    Roy J. Rando

    2012-01-01

    Full Text Available Background. This study examines prevalence of respiratory conditions in New Orleans-area restoration workers after Hurricane Katrina. Methods. Between 2007 and 2010, spirometry and respiratory health and occupational questionnaire were administered to 791 New Orleans-area adults who mostly worked in the building construction and maintenance trades or custodial services. The associations between restoration work hours and lung function and prevalence of respiratory symptoms were examined by multiple linear regression, , or multiple logistic regression. Results. 74% of participants performed post-Katrina restoration work (median time: 620 hours. Symptoms reported include episodes of transient fever/cough (29%, sinus symptoms (48%, pneumonia (3.7%, and new onset asthma (4.5%. Prevalence rate ratios for post-Katrina sinus symptoms (PRR = 1.3; CI: 1.1, 1.7 and fever and cough (PRR = 1.7; CI: 1.3, 2.4 were significantly elevated overall for those who did restoration work and prevalence increased with restoration work hours. Prevalence rate ratios with restoration work were also elevated for new onset asthma (PRR = 2.2; CI: 0.8, 6.2 and pneumonia (PRR = 1.3; CI: 0.5, 3.2 but were not statistically significant. Overall, lung function was slightly depressed but was not significantly different between those with and without restoration work exposure. Conclusions. Post-Katrina restoration work is associated with moderate adverse effects on respiratory health, including sinusitis and toxic pneumonitis.

  16. Effective Social Work Practice in Lagos: An Emerging Megacity ...

    African Journals Online (AJOL)

    Social work is the profession through which social services in theconglomerate of social welfare are provided by professionally trainedpersons. The practice of social work has three perspectives namely: residual, which is ad hoc or reactive, and largely practiced before advent of modern social work profession; institutional ...

  17. The health effects of jobs: status, working conditions, or both?

    Science.gov (United States)

    D'Souza, Rennie M; Strazdins, Lyndall; Clements, Mark S; Broom, Dorothy H; Parslow, Ruth; Rodgers, Bryan

    2005-06-01

    This study investigates whether the association of job strain and insecurity with health differs by status. A cross-sectional study of 2,249 employed workers aged 40-44 years conducted in two regions in south-east Australia in 2000 used a self-completed questionnaire to collect data. Multivariate analyses were used to compare depression, anxiety, physical health and general practitioner (GP) visits over 12 months across categories of job strain and insecurity for three status groups (high, middle and low). High job strain and job insecurity were independently associated with poor mental health, poor physical health and visits to the GP for all status groups when adjusted for confounders. High job strain was associated with depression (OR = 2.46, 95% CI 1.96-3.07), anxiety (OR = 2.56, 95% Cl 2.05-3.20), lower mean physical health scores (-1.11, 95% CI -1.98 - -0.23), and more visits to the GP (IRR = 1.20, 95% CI 1.05-1.37). High job insecurity also showed significant associations with depression (OR = 3.03, 95% Cl 2.03-4.53), anxiety (OR = 2.66, 95% CI 1.81-3.91), and GP visits (IRR = 1.27, 95% CI 1.01-1.60). There were no significant differences by status in the associations of job strain and insecurity with outcomes. High-status workers were just as likely as low-status workers to be exposed to adverse work conditions and both status groups showed similar health effects. Exposure to insecure and high-strain jobs is likely to rise as economies and labour markets respond to globalisation and political change. High status may not protect employees from either exposure or impact, thus widening the population health consequences of adverse work conditions.

  18. Stress Induction and Visual Working Memory Performance: The Effects of Emotional and Non-Emotional Stimuli

    Directory of Open Access Journals (Sweden)

    Zahra Khayyer

    2017-05-01

    Full Text Available Background Some studies have shown working memory impairment following stressful situations. Also, researchers have found that working memory performance depends on many different factors such as emotional load of stimuli and gender. Objectives The present study aimed to determine the effects of stress induction on visual working memory (VWM performance among female and male university students. Methods This quasi-experimental research employed a posttest with only control group design (within-group study. A total of 62 university students (32 males and 30 females were randomly selected and allocated to experimental and control groups (mean age of 23.73. Using cold presser test (CPT, stress was induced and then, an n-back task was implemented to evaluate visual working memory function (such as the number of true items, time reactions, and the number of wrong items through emotional and non-emotional pictures. 100 pictures were selected from the international affective picture system (IASP with different valences. Results Results showed that stress impaired different visual working memory functions (P < 0.002 for true scores, P < 0.001 for reaction time, and P < 0.002 for wrong items. Conclusions In general, stress significantly decreases the VWM performances. On the one hand, females were strongly impressed by stress more than males and on the other hand, the VWM performance was better for emotional stimuli than non-emotional stimuli.

  19. The impact of fatigue and energy on work functioning and impairment in patients with major depressive disorder treated with desvenlafaxine.

    Science.gov (United States)

    Sarfati, David; Evans, Vanessa C; Tam, Edwin M; Woo, Cindy; Iverson, Grant L; Yatham, Lakshmi N; Lam, Raymond W

    2017-11-01

    Fatigue and low energy are cardinal symptoms of major depressive disorder (MDD) that have an impact on work functioning. Antidepressants with noradrenergic activity have been hypothesized to improve symptoms of fatigue and low energy. We examined the impact of these symptoms on work functioning in patients with MDD treated with the serotonin and noradrenaline reuptake inhibitor, desvenlafaxine. A secondary analysis was carried out from a study of employed adult outpatients (n=35) with MDD and subjective cognitive complaints treated with desvenlafaxine 50-100 mg/day for 8 weeks. Multiple regression analyses modeled improvement in work functioning measures (Lam Employment Absence and Productivity Scale, Health and Work Performance Questionnaire, Sheehan Disability Scale) with measures of fatigue (Patient-Reported Outcomes Measurement Information System Fatigue scale and 20-item Hopkins Symptom Check List Energy scale). Patients showed a significant improvement in Montgomery-Åsberg Depression Rating Scale scores as well as in fatigue and work functioning measures following treatment. Fatigue measures were significantly associated with improvement in some (Lam Employment Absence and Productivity Scale, Sheehan Disability Scale), but not all (Health and Work Performance Questionnaire) work functioning measures, independent of improvement in overall depressive symptoms. The limitations of this study include the small sample size and the lack of a placebo or a comparison group. Fatigue and low energy are important symptoms that are associated with occupational impairment in MDD. Treatments that improve these symptoms are likely to improve work functioning.

  20. Low work function materials for microminiature energy conversion and recovery applications

    Energy Technology Data Exchange (ETDEWEB)

    Zavadil, Kevin R.; Ruffner, Judith A.; King, Donald B.

    2003-05-13

    Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties. In the preferred embodiment, the individual layers include mixed BaSrCaO, scandium oxide and tungsten.